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0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Instrumentation/BoundsChecking.cpp | //===- BoundsChecking.cpp - Instrumentation for run-time bounds checking --===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements a pass that instruments the code to perform run-time
// bounds checking on loads, stores, and other memory intrinsics.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Instrumentation.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/Analysis/TargetFolder.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InstIterator.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
#define DEBUG_TYPE "bounds-checking"
static cl::opt<bool> SingleTrapBB("bounds-checking-single-trap",
cl::desc("Use one trap block per function"));
STATISTIC(ChecksAdded, "Bounds checks added");
STATISTIC(ChecksSkipped, "Bounds checks skipped");
STATISTIC(ChecksUnable, "Bounds checks unable to add");
typedef IRBuilder<true, TargetFolder> BuilderTy;
namespace {
struct BoundsChecking : public FunctionPass {
static char ID;
BoundsChecking() : FunctionPass(ID) {
initializeBoundsCheckingPass(*PassRegistry::getPassRegistry());
}
bool runOnFunction(Function &F) override;
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addRequired<TargetLibraryInfoWrapperPass>();
}
private:
const TargetLibraryInfo *TLI;
ObjectSizeOffsetEvaluator *ObjSizeEval;
BuilderTy *Builder;
Instruction *Inst;
BasicBlock *TrapBB;
BasicBlock *getTrapBB();
void emitBranchToTrap(Value *Cmp = nullptr);
bool instrument(Value *Ptr, Value *Val, const DataLayout &DL);
};
}
char BoundsChecking::ID = 0;
INITIALIZE_PASS(BoundsChecking, "bounds-checking", "Run-time bounds checking",
false, false)
/// getTrapBB - create a basic block that traps. All overflowing conditions
/// branch to this block. There's only one trap block per function.
BasicBlock *BoundsChecking::getTrapBB() {
if (TrapBB && SingleTrapBB)
return TrapBB;
Function *Fn = Inst->getParent()->getParent();
IRBuilder<>::InsertPointGuard Guard(*Builder);
TrapBB = BasicBlock::Create(Fn->getContext(), "trap", Fn);
Builder->SetInsertPoint(TrapBB);
llvm::Value *F = Intrinsic::getDeclaration(Fn->getParent(), Intrinsic::trap);
CallInst *TrapCall = Builder->CreateCall(F, {});
TrapCall->setDoesNotReturn();
TrapCall->setDoesNotThrow();
TrapCall->setDebugLoc(Inst->getDebugLoc());
Builder->CreateUnreachable();
return TrapBB;
}
/// emitBranchToTrap - emit a branch instruction to a trap block.
/// If Cmp is non-null, perform a jump only if its value evaluates to true.
void BoundsChecking::emitBranchToTrap(Value *Cmp) {
// check if the comparison is always false
ConstantInt *C = dyn_cast_or_null<ConstantInt>(Cmp);
if (C) {
++ChecksSkipped;
if (!C->getZExtValue())
return;
else
Cmp = nullptr; // unconditional branch
}
++ChecksAdded;
Instruction *Inst = Builder->GetInsertPoint();
BasicBlock *OldBB = Inst->getParent();
BasicBlock *Cont = OldBB->splitBasicBlock(Inst);
OldBB->getTerminator()->eraseFromParent();
if (Cmp)
BranchInst::Create(getTrapBB(), Cont, Cmp, OldBB);
else
BranchInst::Create(getTrapBB(), OldBB);
}
/// instrument - adds run-time bounds checks to memory accessing instructions.
/// Ptr is the pointer that will be read/written, and InstVal is either the
/// result from the load or the value being stored. It is used to determine the
/// size of memory block that is touched.
/// Returns true if any change was made to the IR, false otherwise.
bool BoundsChecking::instrument(Value *Ptr, Value *InstVal,
const DataLayout &DL) {
uint64_t NeededSize = DL.getTypeStoreSize(InstVal->getType());
DEBUG(dbgs() << "Instrument " << *Ptr << " for " << Twine(NeededSize)
<< " bytes\n");
SizeOffsetEvalType SizeOffset = ObjSizeEval->compute(Ptr);
if (!ObjSizeEval->bothKnown(SizeOffset)) {
++ChecksUnable;
return false;
}
Value *Size = SizeOffset.first;
Value *Offset = SizeOffset.second;
ConstantInt *SizeCI = dyn_cast<ConstantInt>(Size);
Type *IntTy = DL.getIntPtrType(Ptr->getType());
Value *NeededSizeVal = ConstantInt::get(IntTy, NeededSize);
// three checks are required to ensure safety:
// . Offset >= 0 (since the offset is given from the base ptr)
// . Size >= Offset (unsigned)
// . Size - Offset >= NeededSize (unsigned)
//
// optimization: if Size >= 0 (signed), skip 1st check
// FIXME: add NSW/NUW here? -- we dont care if the subtraction overflows
Value *ObjSize = Builder->CreateSub(Size, Offset);
Value *Cmp2 = Builder->CreateICmpULT(Size, Offset);
Value *Cmp3 = Builder->CreateICmpULT(ObjSize, NeededSizeVal);
Value *Or = Builder->CreateOr(Cmp2, Cmp3);
if (!SizeCI || SizeCI->getValue().slt(0)) {
Value *Cmp1 = Builder->CreateICmpSLT(Offset, ConstantInt::get(IntTy, 0));
Or = Builder->CreateOr(Cmp1, Or);
}
emitBranchToTrap(Or);
return true;
}
bool BoundsChecking::runOnFunction(Function &F) {
const DataLayout &DL = F.getParent()->getDataLayout();
TLI = &getAnalysis<TargetLibraryInfoWrapperPass>().getTLI();
TrapBB = nullptr;
BuilderTy TheBuilder(F.getContext(), TargetFolder(DL));
Builder = &TheBuilder;
ObjectSizeOffsetEvaluator TheObjSizeEval(DL, TLI, F.getContext(),
/*RoundToAlign=*/true);
ObjSizeEval = &TheObjSizeEval;
// check HANDLE_MEMORY_INST in include/llvm/Instruction.def for memory
// touching instructions
std::vector<Instruction*> WorkList;
for (inst_iterator i = inst_begin(F), e = inst_end(F); i != e; ++i) {
Instruction *I = &*i;
if (isa<LoadInst>(I) || isa<StoreInst>(I) || isa<AtomicCmpXchgInst>(I) ||
isa<AtomicRMWInst>(I))
WorkList.push_back(I);
}
bool MadeChange = false;
for (std::vector<Instruction*>::iterator i = WorkList.begin(),
e = WorkList.end(); i != e; ++i) {
Inst = *i;
Builder->SetInsertPoint(Inst);
if (LoadInst *LI = dyn_cast<LoadInst>(Inst)) {
MadeChange |= instrument(LI->getPointerOperand(), LI, DL);
} else if (StoreInst *SI = dyn_cast<StoreInst>(Inst)) {
MadeChange |=
instrument(SI->getPointerOperand(), SI->getValueOperand(), DL);
} else if (AtomicCmpXchgInst *AI = dyn_cast<AtomicCmpXchgInst>(Inst)) {
MadeChange |=
instrument(AI->getPointerOperand(), AI->getCompareOperand(), DL);
} else if (AtomicRMWInst *AI = dyn_cast<AtomicRMWInst>(Inst)) {
MadeChange |=
instrument(AI->getPointerOperand(), AI->getValOperand(), DL);
} else {
llvm_unreachable("unknown Instruction type");
}
}
return MadeChange;
}
FunctionPass *llvm::createBoundsCheckingPass() {
return new BoundsChecking();
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp | //===-- DataFlowSanitizer.cpp - dynamic data flow analysis ----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
/// \file
/// This file is a part of DataFlowSanitizer, a generalised dynamic data flow
/// analysis.
///
/// Unlike other Sanitizer tools, this tool is not designed to detect a specific
/// class of bugs on its own. Instead, it provides a generic dynamic data flow
/// analysis framework to be used by clients to help detect application-specific
/// issues within their own code.
///
/// The analysis is based on automatic propagation of data flow labels (also
/// known as taint labels) through a program as it performs computation. Each
/// byte of application memory is backed by two bytes of shadow memory which
/// hold the label. On Linux/x86_64, memory is laid out as follows:
///
/// +--------------------+ 0x800000000000 (top of memory)
/// | application memory |
/// +--------------------+ 0x700000008000 (kAppAddr)
/// | |
/// | unused |
/// | |
/// +--------------------+ 0x200200000000 (kUnusedAddr)
/// | union table |
/// +--------------------+ 0x200000000000 (kUnionTableAddr)
/// | shadow memory |
/// +--------------------+ 0x000000010000 (kShadowAddr)
/// | reserved by kernel |
/// +--------------------+ 0x000000000000
///
/// To derive a shadow memory address from an application memory address,
/// bits 44-46 are cleared to bring the address into the range
/// [0x000000008000,0x100000000000). Then the address is shifted left by 1 to
/// account for the double byte representation of shadow labels and move the
/// address into the shadow memory range. See the function
/// DataFlowSanitizer::getShadowAddress below.
///
/// For more information, please refer to the design document:
/// http://clang.llvm.org/docs/DataFlowSanitizerDesign.html
#include "llvm/Transforms/Instrumentation.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InlineAsm.h"
#include "llvm/IR/InstVisitor.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/Value.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/SpecialCaseList.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include <algorithm>
#include <iterator>
#include <set>
#include <utility>
using namespace llvm;
// The -dfsan-preserve-alignment flag controls whether this pass assumes that
// alignment requirements provided by the input IR are correct. For example,
// if the input IR contains a load with alignment 8, this flag will cause
// the shadow load to have alignment 16. This flag is disabled by default as
// we have unfortunately encountered too much code (including Clang itself;
// see PR14291) which performs misaligned access.
static cl::opt<bool> ClPreserveAlignment(
"dfsan-preserve-alignment",
cl::desc("respect alignment requirements provided by input IR"), cl::Hidden,
cl::init(false));
// The ABI list files control how shadow parameters are passed. The pass treats
// every function labelled "uninstrumented" in the ABI list file as conforming
// to the "native" (i.e. unsanitized) ABI. Unless the ABI list contains
// additional annotations for those functions, a call to one of those functions
// will produce a warning message, as the labelling behaviour of the function is
// unknown. The other supported annotations are "functional" and "discard",
// which are described below under DataFlowSanitizer::WrapperKind.
static cl::list<std::string> ClABIListFiles(
"dfsan-abilist",
cl::desc("File listing native ABI functions and how the pass treats them"),
cl::Hidden);
// Controls whether the pass uses IA_Args or IA_TLS as the ABI for instrumented
// functions (see DataFlowSanitizer::InstrumentedABI below).
static cl::opt<bool> ClArgsABI(
"dfsan-args-abi",
cl::desc("Use the argument ABI rather than the TLS ABI"),
cl::Hidden);
// Controls whether the pass includes or ignores the labels of pointers in load
// instructions.
static cl::opt<bool> ClCombinePointerLabelsOnLoad(
"dfsan-combine-pointer-labels-on-load",
cl::desc("Combine the label of the pointer with the label of the data when "
"loading from memory."),
cl::Hidden, cl::init(true));
// Controls whether the pass includes or ignores the labels of pointers in
// stores instructions.
static cl::opt<bool> ClCombinePointerLabelsOnStore(
"dfsan-combine-pointer-labels-on-store",
cl::desc("Combine the label of the pointer with the label of the data when "
"storing in memory."),
cl::Hidden, cl::init(false));
static cl::opt<bool> ClDebugNonzeroLabels(
"dfsan-debug-nonzero-labels",
cl::desc("Insert calls to __dfsan_nonzero_label on observing a parameter, "
"load or return with a nonzero label"),
cl::Hidden);
namespace {
StringRef GetGlobalTypeString(const GlobalValue &G) {
// Types of GlobalVariables are always pointer types.
Type *GType = G.getType()->getElementType();
// For now we support blacklisting struct types only.
if (StructType *SGType = dyn_cast<StructType>(GType)) {
if (!SGType->isLiteral())
return SGType->getName();
}
return "<unknown type>";
}
class DFSanABIList {
std::unique_ptr<SpecialCaseList> SCL;
public:
DFSanABIList() {}
void set(std::unique_ptr<SpecialCaseList> List) { SCL = std::move(List); }
/// Returns whether either this function or its source file are listed in the
/// given category.
bool isIn(const Function &F, StringRef Category) const {
return isIn(*F.getParent(), Category) ||
SCL->inSection("fun", F.getName(), Category);
}
/// Returns whether this global alias is listed in the given category.
///
/// If GA aliases a function, the alias's name is matched as a function name
/// would be. Similarly, aliases of globals are matched like globals.
bool isIn(const GlobalAlias &GA, StringRef Category) const {
if (isIn(*GA.getParent(), Category))
return true;
if (isa<FunctionType>(GA.getType()->getElementType()))
return SCL->inSection("fun", GA.getName(), Category);
return SCL->inSection("global", GA.getName(), Category) ||
SCL->inSection("type", GetGlobalTypeString(GA), Category);
}
/// Returns whether this module is listed in the given category.
bool isIn(const Module &M, StringRef Category) const {
return SCL->inSection("src", M.getModuleIdentifier(), Category);
}
};
class DataFlowSanitizer : public ModulePass {
friend struct DFSanFunction;
friend class DFSanVisitor;
enum {
ShadowWidth = 16
};
/// Which ABI should be used for instrumented functions?
enum InstrumentedABI {
/// Argument and return value labels are passed through additional
/// arguments and by modifying the return type.
IA_Args,
/// Argument and return value labels are passed through TLS variables
/// __dfsan_arg_tls and __dfsan_retval_tls.
IA_TLS
};
/// How should calls to uninstrumented functions be handled?
enum WrapperKind {
/// This function is present in an uninstrumented form but we don't know
/// how it should be handled. Print a warning and call the function anyway.
/// Don't label the return value.
WK_Warning,
/// This function does not write to (user-accessible) memory, and its return
/// value is unlabelled.
WK_Discard,
/// This function does not write to (user-accessible) memory, and the label
/// of its return value is the union of the label of its arguments.
WK_Functional,
/// Instead of calling the function, a custom wrapper __dfsw_F is called,
/// where F is the name of the function. This function may wrap the
/// original function or provide its own implementation. This is similar to
/// the IA_Args ABI, except that IA_Args uses a struct return type to
/// pass the return value shadow in a register, while WK_Custom uses an
/// extra pointer argument to return the shadow. This allows the wrapped
/// form of the function type to be expressed in C.
WK_Custom
};
Module *Mod;
LLVMContext *Ctx;
IntegerType *ShadowTy;
PointerType *ShadowPtrTy;
IntegerType *IntptrTy;
ConstantInt *ZeroShadow;
ConstantInt *ShadowPtrMask;
ConstantInt *ShadowPtrMul;
Constant *ArgTLS;
Constant *RetvalTLS;
void *(*GetArgTLSPtr)();
void *(*GetRetvalTLSPtr)();
Constant *GetArgTLS;
Constant *GetRetvalTLS;
FunctionType *DFSanUnionFnTy;
FunctionType *DFSanUnionLoadFnTy;
FunctionType *DFSanUnimplementedFnTy;
FunctionType *DFSanSetLabelFnTy;
FunctionType *DFSanNonzeroLabelFnTy;
FunctionType *DFSanVarargWrapperFnTy;
Constant *DFSanUnionFn;
Constant *DFSanCheckedUnionFn;
Constant *DFSanUnionLoadFn;
Constant *DFSanUnimplementedFn;
Constant *DFSanSetLabelFn;
Constant *DFSanNonzeroLabelFn;
Constant *DFSanVarargWrapperFn;
MDNode *ColdCallWeights;
DFSanABIList ABIList;
DenseMap<Value *, Function *> UnwrappedFnMap;
AttributeSet ReadOnlyNoneAttrs;
DenseMap<const Function *, DISubprogram *> FunctionDIs;
Value *getShadowAddress(Value *Addr, Instruction *Pos);
bool isInstrumented(const Function *F);
bool isInstrumented(const GlobalAlias *GA);
FunctionType *getArgsFunctionType(FunctionType *T);
FunctionType *getTrampolineFunctionType(FunctionType *T);
FunctionType *getCustomFunctionType(FunctionType *T);
InstrumentedABI getInstrumentedABI();
WrapperKind getWrapperKind(Function *F);
void addGlobalNamePrefix(GlobalValue *GV);
Function *buildWrapperFunction(Function *F, StringRef NewFName,
GlobalValue::LinkageTypes NewFLink,
FunctionType *NewFT);
Constant *getOrBuildTrampolineFunction(FunctionType *FT, StringRef FName);
public:
DataFlowSanitizer(
const std::vector<std::string> &ABIListFiles = std::vector<std::string>(),
void *(*getArgTLS)() = nullptr, void *(*getRetValTLS)() = nullptr);
static char ID;
bool doInitialization(Module &M) override;
bool runOnModule(Module &M) override;
};
struct DFSanFunction {
DataFlowSanitizer &DFS;
Function *F;
DominatorTree DT;
DataFlowSanitizer::InstrumentedABI IA;
bool IsNativeABI;
Value *ArgTLSPtr;
Value *RetvalTLSPtr;
AllocaInst *LabelReturnAlloca;
DenseMap<Value *, Value *> ValShadowMap;
DenseMap<AllocaInst *, AllocaInst *> AllocaShadowMap;
std::vector<std::pair<PHINode *, PHINode *> > PHIFixups;
DenseSet<Instruction *> SkipInsts;
std::vector<Value *> NonZeroChecks;
bool AvoidNewBlocks;
struct CachedCombinedShadow {
BasicBlock *Block;
Value *Shadow;
};
DenseMap<std::pair<Value *, Value *>, CachedCombinedShadow>
CachedCombinedShadows;
DenseMap<Value *, std::set<Value *>> ShadowElements;
DFSanFunction(DataFlowSanitizer &DFS, Function *F, bool IsNativeABI)
: DFS(DFS), F(F), IA(DFS.getInstrumentedABI()),
IsNativeABI(IsNativeABI), ArgTLSPtr(nullptr), RetvalTLSPtr(nullptr),
LabelReturnAlloca(nullptr) {
DT.recalculate(*F);
// FIXME: Need to track down the register allocator issue which causes poor
// performance in pathological cases with large numbers of basic blocks.
AvoidNewBlocks = F->size() > 1000;
}
Value *getArgTLSPtr();
Value *getArgTLS(unsigned Index, Instruction *Pos);
Value *getRetvalTLS();
Value *getShadow(Value *V);
void setShadow(Instruction *I, Value *Shadow);
Value *combineShadows(Value *V1, Value *V2, Instruction *Pos);
Value *combineOperandShadows(Instruction *Inst);
Value *loadShadow(Value *ShadowAddr, uint64_t Size, uint64_t Align,
Instruction *Pos);
void storeShadow(Value *Addr, uint64_t Size, uint64_t Align, Value *Shadow,
Instruction *Pos);
};
class DFSanVisitor : public InstVisitor<DFSanVisitor> {
public:
DFSanFunction &DFSF;
DFSanVisitor(DFSanFunction &DFSF) : DFSF(DFSF) {}
void visitOperandShadowInst(Instruction &I);
void visitBinaryOperator(BinaryOperator &BO);
void visitCastInst(CastInst &CI);
void visitCmpInst(CmpInst &CI);
void visitGetElementPtrInst(GetElementPtrInst &GEPI);
void visitLoadInst(LoadInst &LI);
void visitStoreInst(StoreInst &SI);
void visitReturnInst(ReturnInst &RI);
void visitCallSite(CallSite CS);
void visitPHINode(PHINode &PN);
void visitExtractElementInst(ExtractElementInst &I);
void visitInsertElementInst(InsertElementInst &I);
void visitShuffleVectorInst(ShuffleVectorInst &I);
void visitExtractValueInst(ExtractValueInst &I);
void visitInsertValueInst(InsertValueInst &I);
void visitAllocaInst(AllocaInst &I);
void visitSelectInst(SelectInst &I);
void visitMemSetInst(MemSetInst &I);
void visitMemTransferInst(MemTransferInst &I);
};
}
char DataFlowSanitizer::ID;
INITIALIZE_PASS(DataFlowSanitizer, "dfsan",
"DataFlowSanitizer: dynamic data flow analysis.", false, false)
ModulePass *
llvm::createDataFlowSanitizerPass(const std::vector<std::string> &ABIListFiles,
void *(*getArgTLS)(),
void *(*getRetValTLS)()) {
return new DataFlowSanitizer(ABIListFiles, getArgTLS, getRetValTLS);
}
DataFlowSanitizer::DataFlowSanitizer(
const std::vector<std::string> &ABIListFiles, void *(*getArgTLS)(),
void *(*getRetValTLS)())
: ModulePass(ID), GetArgTLSPtr(getArgTLS), GetRetvalTLSPtr(getRetValTLS) {
std::vector<std::string> AllABIListFiles(std::move(ABIListFiles));
AllABIListFiles.insert(AllABIListFiles.end(), ClABIListFiles.begin(),
ClABIListFiles.end());
ABIList.set(SpecialCaseList::createOrDie(AllABIListFiles));
}
FunctionType *DataFlowSanitizer::getArgsFunctionType(FunctionType *T) {
llvm::SmallVector<Type *, 4> ArgTypes(T->param_begin(), T->param_end());
ArgTypes.append(T->getNumParams(), ShadowTy);
if (T->isVarArg())
ArgTypes.push_back(ShadowPtrTy);
Type *RetType = T->getReturnType();
if (!RetType->isVoidTy())
RetType = StructType::get(RetType, ShadowTy, (Type *)nullptr);
return FunctionType::get(RetType, ArgTypes, T->isVarArg());
}
FunctionType *DataFlowSanitizer::getTrampolineFunctionType(FunctionType *T) {
assert(!T->isVarArg());
llvm::SmallVector<Type *, 4> ArgTypes;
ArgTypes.push_back(T->getPointerTo());
ArgTypes.append(T->param_begin(), T->param_end());
ArgTypes.append(T->getNumParams(), ShadowTy);
Type *RetType = T->getReturnType();
if (!RetType->isVoidTy())
ArgTypes.push_back(ShadowPtrTy);
return FunctionType::get(T->getReturnType(), ArgTypes, false);
}
FunctionType *DataFlowSanitizer::getCustomFunctionType(FunctionType *T) {
llvm::SmallVector<Type *, 4> ArgTypes;
for (FunctionType::param_iterator i = T->param_begin(), e = T->param_end();
i != e; ++i) {
FunctionType *FT;
if (isa<PointerType>(*i) && (FT = dyn_cast<FunctionType>(cast<PointerType>(
*i)->getElementType()))) {
ArgTypes.push_back(getTrampolineFunctionType(FT)->getPointerTo());
ArgTypes.push_back(Type::getInt8PtrTy(*Ctx));
} else {
ArgTypes.push_back(*i);
}
}
for (unsigned i = 0, e = T->getNumParams(); i != e; ++i)
ArgTypes.push_back(ShadowTy);
if (T->isVarArg())
ArgTypes.push_back(ShadowPtrTy);
Type *RetType = T->getReturnType();
if (!RetType->isVoidTy())
ArgTypes.push_back(ShadowPtrTy);
return FunctionType::get(T->getReturnType(), ArgTypes, T->isVarArg());
}
bool DataFlowSanitizer::doInitialization(Module &M) {
llvm::Triple TargetTriple(M.getTargetTriple());
bool IsX86_64 = TargetTriple.getArch() == llvm::Triple::x86_64;
bool IsMIPS64 = TargetTriple.getArch() == llvm::Triple::mips64 ||
TargetTriple.getArch() == llvm::Triple::mips64el;
const DataLayout &DL = M.getDataLayout();
Mod = &M;
Ctx = &M.getContext();
ShadowTy = IntegerType::get(*Ctx, ShadowWidth);
ShadowPtrTy = PointerType::getUnqual(ShadowTy);
IntptrTy = DL.getIntPtrType(*Ctx);
ZeroShadow = ConstantInt::getSigned(ShadowTy, 0);
ShadowPtrMul = ConstantInt::getSigned(IntptrTy, ShadowWidth / 8);
if (IsX86_64)
ShadowPtrMask = ConstantInt::getSigned(IntptrTy, ~0x700000000000LL);
else if (IsMIPS64)
ShadowPtrMask = ConstantInt::getSigned(IntptrTy, ~0xF000000000LL);
else
report_fatal_error("unsupported triple");
Type *DFSanUnionArgs[2] = { ShadowTy, ShadowTy };
DFSanUnionFnTy =
FunctionType::get(ShadowTy, DFSanUnionArgs, /*isVarArg=*/ false);
Type *DFSanUnionLoadArgs[2] = { ShadowPtrTy, IntptrTy };
DFSanUnionLoadFnTy =
FunctionType::get(ShadowTy, DFSanUnionLoadArgs, /*isVarArg=*/ false);
DFSanUnimplementedFnTy = FunctionType::get(
Type::getVoidTy(*Ctx), Type::getInt8PtrTy(*Ctx), /*isVarArg=*/false);
Type *DFSanSetLabelArgs[3] = { ShadowTy, Type::getInt8PtrTy(*Ctx), IntptrTy };
DFSanSetLabelFnTy = FunctionType::get(Type::getVoidTy(*Ctx),
DFSanSetLabelArgs, /*isVarArg=*/false);
DFSanNonzeroLabelFnTy = FunctionType::get(
Type::getVoidTy(*Ctx), None, /*isVarArg=*/false);
DFSanVarargWrapperFnTy = FunctionType::get(
Type::getVoidTy(*Ctx), Type::getInt8PtrTy(*Ctx), /*isVarArg=*/false);
if (GetArgTLSPtr) {
Type *ArgTLSTy = ArrayType::get(ShadowTy, 64);
ArgTLS = nullptr;
GetArgTLS = ConstantExpr::getIntToPtr(
ConstantInt::get(IntptrTy, uintptr_t(GetArgTLSPtr)),
PointerType::getUnqual(
FunctionType::get(PointerType::getUnqual(ArgTLSTy),
(Type *)nullptr)));
}
if (GetRetvalTLSPtr) {
RetvalTLS = nullptr;
GetRetvalTLS = ConstantExpr::getIntToPtr(
ConstantInt::get(IntptrTy, uintptr_t(GetRetvalTLSPtr)),
PointerType::getUnqual(
FunctionType::get(PointerType::getUnqual(ShadowTy),
(Type *)nullptr)));
}
ColdCallWeights = MDBuilder(*Ctx).createBranchWeights(1, 1000);
return true;
}
bool DataFlowSanitizer::isInstrumented(const Function *F) {
return !ABIList.isIn(*F, "uninstrumented");
}
bool DataFlowSanitizer::isInstrumented(const GlobalAlias *GA) {
return !ABIList.isIn(*GA, "uninstrumented");
}
DataFlowSanitizer::InstrumentedABI DataFlowSanitizer::getInstrumentedABI() {
return ClArgsABI ? IA_Args : IA_TLS;
}
DataFlowSanitizer::WrapperKind DataFlowSanitizer::getWrapperKind(Function *F) {
if (ABIList.isIn(*F, "functional"))
return WK_Functional;
if (ABIList.isIn(*F, "discard"))
return WK_Discard;
if (ABIList.isIn(*F, "custom"))
return WK_Custom;
return WK_Warning;
}
void DataFlowSanitizer::addGlobalNamePrefix(GlobalValue *GV) {
std::string GVName = GV->getName(), Prefix = "dfs$";
GV->setName(Prefix + GVName);
// Try to change the name of the function in module inline asm. We only do
// this for specific asm directives, currently only ".symver", to try to avoid
// corrupting asm which happens to contain the symbol name as a substring.
// Note that the substitution for .symver assumes that the versioned symbol
// also has an instrumented name.
std::string Asm = GV->getParent()->getModuleInlineAsm();
std::string SearchStr = ".symver " + GVName + ",";
size_t Pos = Asm.find(SearchStr);
if (Pos != std::string::npos) {
Asm.replace(Pos, SearchStr.size(),
".symver " + Prefix + GVName + "," + Prefix);
GV->getParent()->setModuleInlineAsm(Asm);
}
}
Function *
DataFlowSanitizer::buildWrapperFunction(Function *F, StringRef NewFName,
GlobalValue::LinkageTypes NewFLink,
FunctionType *NewFT) {
FunctionType *FT = F->getFunctionType();
Function *NewF = Function::Create(NewFT, NewFLink, NewFName,
F->getParent());
NewF->copyAttributesFrom(F);
NewF->removeAttributes(
AttributeSet::ReturnIndex,
AttributeSet::get(F->getContext(), AttributeSet::ReturnIndex,
AttributeFuncs::typeIncompatible(NewFT->getReturnType())));
BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", NewF);
if (F->isVarArg()) {
NewF->removeAttributes(
AttributeSet::FunctionIndex,
AttributeSet().addAttribute(*Ctx, AttributeSet::FunctionIndex,
"split-stack"));
CallInst::Create(DFSanVarargWrapperFn,
IRBuilder<>(BB).CreateGlobalStringPtr(F->getName()), "",
BB);
new UnreachableInst(*Ctx, BB);
} else {
std::vector<Value *> Args;
unsigned n = FT->getNumParams();
for (Function::arg_iterator ai = NewF->arg_begin(); n != 0; ++ai, --n)
Args.push_back(&*ai);
CallInst *CI = CallInst::Create(F, Args, "", BB);
if (FT->getReturnType()->isVoidTy())
ReturnInst::Create(*Ctx, BB);
else
ReturnInst::Create(*Ctx, CI, BB);
}
return NewF;
}
Constant *DataFlowSanitizer::getOrBuildTrampolineFunction(FunctionType *FT,
StringRef FName) {
FunctionType *FTT = getTrampolineFunctionType(FT);
Constant *C = Mod->getOrInsertFunction(FName, FTT);
Function *F = dyn_cast<Function>(C);
if (F && F->isDeclaration()) {
F->setLinkage(GlobalValue::LinkOnceODRLinkage);
BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", F);
std::vector<Value *> Args;
Function::arg_iterator AI = F->arg_begin(); ++AI;
for (unsigned N = FT->getNumParams(); N != 0; ++AI, --N)
Args.push_back(&*AI);
CallInst *CI =
CallInst::Create(&F->getArgumentList().front(), Args, "", BB);
ReturnInst *RI;
if (FT->getReturnType()->isVoidTy())
RI = ReturnInst::Create(*Ctx, BB);
else
RI = ReturnInst::Create(*Ctx, CI, BB);
DFSanFunction DFSF(*this, F, /*IsNativeABI=*/true);
Function::arg_iterator ValAI = F->arg_begin(), ShadowAI = AI; ++ValAI;
for (unsigned N = FT->getNumParams(); N != 0; ++ValAI, ++ShadowAI, --N)
DFSF.ValShadowMap[ValAI] = ShadowAI;
DFSanVisitor(DFSF).visitCallInst(*CI);
if (!FT->getReturnType()->isVoidTy())
new StoreInst(DFSF.getShadow(RI->getReturnValue()),
&F->getArgumentList().back(), RI);
}
return C;
}
bool DataFlowSanitizer::runOnModule(Module &M) {
if (ABIList.isIn(M, "skip"))
return false;
FunctionDIs = makeSubprogramMap(M);
if (!GetArgTLSPtr) {
Type *ArgTLSTy = ArrayType::get(ShadowTy, 64);
ArgTLS = Mod->getOrInsertGlobal("__dfsan_arg_tls", ArgTLSTy);
if (GlobalVariable *G = dyn_cast<GlobalVariable>(ArgTLS))
G->setThreadLocalMode(GlobalVariable::InitialExecTLSModel);
}
if (!GetRetvalTLSPtr) {
RetvalTLS = Mod->getOrInsertGlobal("__dfsan_retval_tls", ShadowTy);
if (GlobalVariable *G = dyn_cast<GlobalVariable>(RetvalTLS))
G->setThreadLocalMode(GlobalVariable::InitialExecTLSModel);
}
DFSanUnionFn = Mod->getOrInsertFunction("__dfsan_union", DFSanUnionFnTy);
if (Function *F = dyn_cast<Function>(DFSanUnionFn)) {
F->addAttribute(AttributeSet::FunctionIndex, Attribute::NoUnwind);
F->addAttribute(AttributeSet::FunctionIndex, Attribute::ReadNone);
F->addAttribute(AttributeSet::ReturnIndex, Attribute::ZExt);
F->addAttribute(1, Attribute::ZExt);
F->addAttribute(2, Attribute::ZExt);
}
DFSanCheckedUnionFn = Mod->getOrInsertFunction("dfsan_union", DFSanUnionFnTy);
if (Function *F = dyn_cast<Function>(DFSanCheckedUnionFn)) {
F->addAttribute(AttributeSet::FunctionIndex, Attribute::NoUnwind);
F->addAttribute(AttributeSet::FunctionIndex, Attribute::ReadNone);
F->addAttribute(AttributeSet::ReturnIndex, Attribute::ZExt);
F->addAttribute(1, Attribute::ZExt);
F->addAttribute(2, Attribute::ZExt);
}
DFSanUnionLoadFn =
Mod->getOrInsertFunction("__dfsan_union_load", DFSanUnionLoadFnTy);
if (Function *F = dyn_cast<Function>(DFSanUnionLoadFn)) {
F->addAttribute(AttributeSet::FunctionIndex, Attribute::NoUnwind);
F->addAttribute(AttributeSet::FunctionIndex, Attribute::ReadOnly);
F->addAttribute(AttributeSet::ReturnIndex, Attribute::ZExt);
}
DFSanUnimplementedFn =
Mod->getOrInsertFunction("__dfsan_unimplemented", DFSanUnimplementedFnTy);
DFSanSetLabelFn =
Mod->getOrInsertFunction("__dfsan_set_label", DFSanSetLabelFnTy);
if (Function *F = dyn_cast<Function>(DFSanSetLabelFn)) {
F->addAttribute(1, Attribute::ZExt);
}
DFSanNonzeroLabelFn =
Mod->getOrInsertFunction("__dfsan_nonzero_label", DFSanNonzeroLabelFnTy);
DFSanVarargWrapperFn = Mod->getOrInsertFunction("__dfsan_vararg_wrapper",
DFSanVarargWrapperFnTy);
std::vector<Function *> FnsToInstrument;
llvm::SmallPtrSet<Function *, 2> FnsWithNativeABI;
for (Module::iterator i = M.begin(), e = M.end(); i != e; ++i) {
if (!i->isIntrinsic() &&
i != DFSanUnionFn &&
i != DFSanCheckedUnionFn &&
i != DFSanUnionLoadFn &&
i != DFSanUnimplementedFn &&
i != DFSanSetLabelFn &&
i != DFSanNonzeroLabelFn &&
i != DFSanVarargWrapperFn)
FnsToInstrument.push_back(&*i);
}
// Give function aliases prefixes when necessary, and build wrappers where the
// instrumentedness is inconsistent.
for (Module::alias_iterator i = M.alias_begin(), e = M.alias_end(); i != e;) {
GlobalAlias *GA = &*i;
++i;
// Don't stop on weak. We assume people aren't playing games with the
// instrumentedness of overridden weak aliases.
if (auto F = dyn_cast<Function>(GA->getBaseObject())) {
bool GAInst = isInstrumented(GA), FInst = isInstrumented(F);
if (GAInst && FInst) {
addGlobalNamePrefix(GA);
} else if (GAInst != FInst) {
// Non-instrumented alias of an instrumented function, or vice versa.
// Replace the alias with a native-ABI wrapper of the aliasee. The pass
// below will take care of instrumenting it.
Function *NewF =
buildWrapperFunction(F, "", GA->getLinkage(), F->getFunctionType());
GA->replaceAllUsesWith(ConstantExpr::getBitCast(NewF, GA->getType()));
NewF->takeName(GA);
GA->eraseFromParent();
FnsToInstrument.push_back(NewF);
}
}
}
AttrBuilder B;
B.addAttribute(Attribute::ReadOnly).addAttribute(Attribute::ReadNone);
ReadOnlyNoneAttrs = AttributeSet::get(*Ctx, AttributeSet::FunctionIndex, B);
// First, change the ABI of every function in the module. ABI-listed
// functions keep their original ABI and get a wrapper function.
for (std::vector<Function *>::iterator i = FnsToInstrument.begin(),
e = FnsToInstrument.end();
i != e; ++i) {
Function &F = **i;
FunctionType *FT = F.getFunctionType();
bool IsZeroArgsVoidRet = (FT->getNumParams() == 0 && !FT->isVarArg() &&
FT->getReturnType()->isVoidTy());
if (isInstrumented(&F)) {
// Instrumented functions get a 'dfs$' prefix. This allows us to more
// easily identify cases of mismatching ABIs.
if (getInstrumentedABI() == IA_Args && !IsZeroArgsVoidRet) {
FunctionType *NewFT = getArgsFunctionType(FT);
Function *NewF = Function::Create(NewFT, F.getLinkage(), "", &M);
NewF->copyAttributesFrom(&F);
NewF->removeAttributes(
AttributeSet::ReturnIndex,
AttributeSet::get(NewF->getContext(), AttributeSet::ReturnIndex,
AttributeFuncs::typeIncompatible(NewFT->getReturnType())));
for (Function::arg_iterator FArg = F.arg_begin(),
NewFArg = NewF->arg_begin(),
FArgEnd = F.arg_end();
FArg != FArgEnd; ++FArg, ++NewFArg) {
FArg->replaceAllUsesWith(NewFArg);
}
NewF->getBasicBlockList().splice(NewF->begin(), F.getBasicBlockList());
for (Function::user_iterator UI = F.user_begin(), UE = F.user_end();
UI != UE;) {
BlockAddress *BA = dyn_cast<BlockAddress>(*UI);
++UI;
if (BA) {
BA->replaceAllUsesWith(
BlockAddress::get(NewF, BA->getBasicBlock()));
delete BA;
}
}
F.replaceAllUsesWith(
ConstantExpr::getBitCast(NewF, PointerType::getUnqual(FT)));
NewF->takeName(&F);
F.eraseFromParent();
*i = NewF;
addGlobalNamePrefix(NewF);
} else {
addGlobalNamePrefix(&F);
}
} else if (!IsZeroArgsVoidRet || getWrapperKind(&F) == WK_Custom) {
// Build a wrapper function for F. The wrapper simply calls F, and is
// added to FnsToInstrument so that any instrumentation according to its
// WrapperKind is done in the second pass below.
FunctionType *NewFT = getInstrumentedABI() == IA_Args
? getArgsFunctionType(FT)
: FT;
Function *NewF = buildWrapperFunction(
&F, std::string("dfsw$") + std::string(F.getName()),
GlobalValue::LinkOnceODRLinkage, NewFT);
if (getInstrumentedABI() == IA_TLS)
NewF->removeAttributes(AttributeSet::FunctionIndex, ReadOnlyNoneAttrs);
Value *WrappedFnCst =
ConstantExpr::getBitCast(NewF, PointerType::getUnqual(FT));
F.replaceAllUsesWith(WrappedFnCst);
// Patch the pointer to LLVM function in debug info descriptor.
auto DI = FunctionDIs.find(&F);
if (DI != FunctionDIs.end())
DI->second->replaceFunction(&F);
UnwrappedFnMap[WrappedFnCst] = &F;
*i = NewF;
if (!F.isDeclaration()) {
// This function is probably defining an interposition of an
// uninstrumented function and hence needs to keep the original ABI.
// But any functions it may call need to use the instrumented ABI, so
// we instrument it in a mode which preserves the original ABI.
FnsWithNativeABI.insert(&F);
// This code needs to rebuild the iterators, as they may be invalidated
// by the push_back, taking care that the new range does not include
// any functions added by this code.
size_t N = i - FnsToInstrument.begin(),
Count = e - FnsToInstrument.begin();
FnsToInstrument.push_back(&F);
i = FnsToInstrument.begin() + N;
e = FnsToInstrument.begin() + Count;
}
// Hopefully, nobody will try to indirectly call a vararg
// function... yet.
} else if (FT->isVarArg()) {
UnwrappedFnMap[&F] = &F;
*i = nullptr;
}
}
for (std::vector<Function *>::iterator i = FnsToInstrument.begin(),
e = FnsToInstrument.end();
i != e; ++i) {
if (!*i || (*i)->isDeclaration())
continue;
removeUnreachableBlocks(**i);
DFSanFunction DFSF(*this, *i, FnsWithNativeABI.count(*i));
// DFSanVisitor may create new basic blocks, which confuses df_iterator.
// Build a copy of the list before iterating over it.
llvm::SmallVector<BasicBlock *, 4> BBList(
depth_first(&(*i)->getEntryBlock()));
for (llvm::SmallVector<BasicBlock *, 4>::iterator i = BBList.begin(),
e = BBList.end();
i != e; ++i) {
Instruction *Inst = &(*i)->front();
while (1) {
// DFSanVisitor may split the current basic block, changing the current
// instruction's next pointer and moving the next instruction to the
// tail block from which we should continue.
Instruction *Next = Inst->getNextNode();
// DFSanVisitor may delete Inst, so keep track of whether it was a
// terminator.
bool IsTerminator = isa<TerminatorInst>(Inst);
if (!DFSF.SkipInsts.count(Inst))
DFSanVisitor(DFSF).visit(Inst);
if (IsTerminator)
break;
Inst = Next;
}
}
// We will not necessarily be able to compute the shadow for every phi node
// until we have visited every block. Therefore, the code that handles phi
// nodes adds them to the PHIFixups list so that they can be properly
// handled here.
for (std::vector<std::pair<PHINode *, PHINode *> >::iterator
i = DFSF.PHIFixups.begin(),
e = DFSF.PHIFixups.end();
i != e; ++i) {
for (unsigned val = 0, n = i->first->getNumIncomingValues(); val != n;
++val) {
i->second->setIncomingValue(
val, DFSF.getShadow(i->first->getIncomingValue(val)));
}
}
// -dfsan-debug-nonzero-labels will split the CFG in all kinds of crazy
// places (i.e. instructions in basic blocks we haven't even begun visiting
// yet). To make our life easier, do this work in a pass after the main
// instrumentation.
if (ClDebugNonzeroLabels) {
for (Value *V : DFSF.NonZeroChecks) {
Instruction *Pos;
if (Instruction *I = dyn_cast<Instruction>(V))
Pos = I->getNextNode();
else
Pos = DFSF.F->getEntryBlock().begin();
while (isa<PHINode>(Pos) || isa<AllocaInst>(Pos))
Pos = Pos->getNextNode();
IRBuilder<> IRB(Pos);
Value *Ne = IRB.CreateICmpNE(V, DFSF.DFS.ZeroShadow);
BranchInst *BI = cast<BranchInst>(SplitBlockAndInsertIfThen(
Ne, Pos, /*Unreachable=*/false, ColdCallWeights));
IRBuilder<> ThenIRB(BI);
ThenIRB.CreateCall(DFSF.DFS.DFSanNonzeroLabelFn, {});
}
}
}
return false;
}
Value *DFSanFunction::getArgTLSPtr() {
if (ArgTLSPtr)
return ArgTLSPtr;
if (DFS.ArgTLS)
return ArgTLSPtr = DFS.ArgTLS;
IRBuilder<> IRB(F->getEntryBlock().begin());
return ArgTLSPtr = IRB.CreateCall(DFS.GetArgTLS, {});
}
Value *DFSanFunction::getRetvalTLS() {
if (RetvalTLSPtr)
return RetvalTLSPtr;
if (DFS.RetvalTLS)
return RetvalTLSPtr = DFS.RetvalTLS;
IRBuilder<> IRB(F->getEntryBlock().begin());
return RetvalTLSPtr = IRB.CreateCall(DFS.GetRetvalTLS, {});
}
Value *DFSanFunction::getArgTLS(unsigned Idx, Instruction *Pos) {
IRBuilder<> IRB(Pos);
return IRB.CreateConstGEP2_64(getArgTLSPtr(), 0, Idx);
}
Value *DFSanFunction::getShadow(Value *V) {
if (!isa<Argument>(V) && !isa<Instruction>(V))
return DFS.ZeroShadow;
Value *&Shadow = ValShadowMap[V];
if (!Shadow) {
if (Argument *A = dyn_cast<Argument>(V)) {
if (IsNativeABI)
return DFS.ZeroShadow;
switch (IA) {
case DataFlowSanitizer::IA_TLS: {
Value *ArgTLSPtr = getArgTLSPtr();
Instruction *ArgTLSPos =
DFS.ArgTLS ? &*F->getEntryBlock().begin()
: cast<Instruction>(ArgTLSPtr)->getNextNode();
IRBuilder<> IRB(ArgTLSPos);
Shadow = IRB.CreateLoad(getArgTLS(A->getArgNo(), ArgTLSPos));
break;
}
case DataFlowSanitizer::IA_Args: {
unsigned ArgIdx = A->getArgNo() + F->getArgumentList().size() / 2;
Function::arg_iterator i = F->arg_begin();
while (ArgIdx--)
++i;
Shadow = i;
assert(Shadow->getType() == DFS.ShadowTy);
break;
}
}
NonZeroChecks.push_back(Shadow);
} else {
Shadow = DFS.ZeroShadow;
}
}
return Shadow;
}
void DFSanFunction::setShadow(Instruction *I, Value *Shadow) {
assert(!ValShadowMap.count(I));
assert(Shadow->getType() == DFS.ShadowTy);
ValShadowMap[I] = Shadow;
}
Value *DataFlowSanitizer::getShadowAddress(Value *Addr, Instruction *Pos) {
assert(Addr != RetvalTLS && "Reinstrumenting?");
IRBuilder<> IRB(Pos);
return IRB.CreateIntToPtr(
IRB.CreateMul(
IRB.CreateAnd(IRB.CreatePtrToInt(Addr, IntptrTy), ShadowPtrMask),
ShadowPtrMul),
ShadowPtrTy);
}
// Generates IR to compute the union of the two given shadows, inserting it
// before Pos. Returns the computed union Value.
Value *DFSanFunction::combineShadows(Value *V1, Value *V2, Instruction *Pos) {
if (V1 == DFS.ZeroShadow)
return V2;
if (V2 == DFS.ZeroShadow)
return V1;
if (V1 == V2)
return V1;
auto V1Elems = ShadowElements.find(V1);
auto V2Elems = ShadowElements.find(V2);
if (V1Elems != ShadowElements.end() && V2Elems != ShadowElements.end()) {
if (std::includes(V1Elems->second.begin(), V1Elems->second.end(),
V2Elems->second.begin(), V2Elems->second.end())) {
return V1;
} else if (std::includes(V2Elems->second.begin(), V2Elems->second.end(),
V1Elems->second.begin(), V1Elems->second.end())) {
return V2;
}
} else if (V1Elems != ShadowElements.end()) {
if (V1Elems->second.count(V2))
return V1;
} else if (V2Elems != ShadowElements.end()) {
if (V2Elems->second.count(V1))
return V2;
}
auto Key = std::make_pair(V1, V2);
if (V1 > V2)
std::swap(Key.first, Key.second);
CachedCombinedShadow &CCS = CachedCombinedShadows[Key];
if (CCS.Block && DT.dominates(CCS.Block, Pos->getParent()))
return CCS.Shadow;
IRBuilder<> IRB(Pos);
if (AvoidNewBlocks) {
CallInst *Call = IRB.CreateCall(DFS.DFSanCheckedUnionFn, {V1, V2});
Call->addAttribute(AttributeSet::ReturnIndex, Attribute::ZExt);
Call->addAttribute(1, Attribute::ZExt);
Call->addAttribute(2, Attribute::ZExt);
CCS.Block = Pos->getParent();
CCS.Shadow = Call;
} else {
BasicBlock *Head = Pos->getParent();
Value *Ne = IRB.CreateICmpNE(V1, V2);
BranchInst *BI = cast<BranchInst>(SplitBlockAndInsertIfThen(
Ne, Pos, /*Unreachable=*/false, DFS.ColdCallWeights, &DT));
IRBuilder<> ThenIRB(BI);
CallInst *Call = ThenIRB.CreateCall(DFS.DFSanUnionFn, {V1, V2});
Call->addAttribute(AttributeSet::ReturnIndex, Attribute::ZExt);
Call->addAttribute(1, Attribute::ZExt);
Call->addAttribute(2, Attribute::ZExt);
BasicBlock *Tail = BI->getSuccessor(0);
PHINode *Phi = PHINode::Create(DFS.ShadowTy, 2, "", Tail->begin());
Phi->addIncoming(Call, Call->getParent());
Phi->addIncoming(V1, Head);
CCS.Block = Tail;
CCS.Shadow = Phi;
}
std::set<Value *> UnionElems;
if (V1Elems != ShadowElements.end()) {
UnionElems = V1Elems->second;
} else {
UnionElems.insert(V1);
}
if (V2Elems != ShadowElements.end()) {
UnionElems.insert(V2Elems->second.begin(), V2Elems->second.end());
} else {
UnionElems.insert(V2);
}
ShadowElements[CCS.Shadow] = std::move(UnionElems);
return CCS.Shadow;
}
// A convenience function which folds the shadows of each of the operands
// of the provided instruction Inst, inserting the IR before Inst. Returns
// the computed union Value.
Value *DFSanFunction::combineOperandShadows(Instruction *Inst) {
if (Inst->getNumOperands() == 0)
return DFS.ZeroShadow;
Value *Shadow = getShadow(Inst->getOperand(0));
for (unsigned i = 1, n = Inst->getNumOperands(); i != n; ++i) {
Shadow = combineShadows(Shadow, getShadow(Inst->getOperand(i)), Inst);
}
return Shadow;
}
void DFSanVisitor::visitOperandShadowInst(Instruction &I) {
Value *CombinedShadow = DFSF.combineOperandShadows(&I);
DFSF.setShadow(&I, CombinedShadow);
}
// Generates IR to load shadow corresponding to bytes [Addr, Addr+Size), where
// Addr has alignment Align, and take the union of each of those shadows.
Value *DFSanFunction::loadShadow(Value *Addr, uint64_t Size, uint64_t Align,
Instruction *Pos) {
if (AllocaInst *AI = dyn_cast<AllocaInst>(Addr)) {
llvm::DenseMap<AllocaInst *, AllocaInst *>::iterator i =
AllocaShadowMap.find(AI);
if (i != AllocaShadowMap.end()) {
IRBuilder<> IRB(Pos);
return IRB.CreateLoad(i->second);
}
}
uint64_t ShadowAlign = Align * DFS.ShadowWidth / 8;
SmallVector<Value *, 2> Objs;
GetUnderlyingObjects(Addr, Objs, Pos->getModule()->getDataLayout());
bool AllConstants = true;
for (SmallVector<Value *, 2>::iterator i = Objs.begin(), e = Objs.end();
i != e; ++i) {
if (isa<Function>(*i) || isa<BlockAddress>(*i))
continue;
if (isa<GlobalVariable>(*i) && cast<GlobalVariable>(*i)->isConstant())
continue;
AllConstants = false;
break;
}
if (AllConstants)
return DFS.ZeroShadow;
Value *ShadowAddr = DFS.getShadowAddress(Addr, Pos);
switch (Size) {
case 0:
return DFS.ZeroShadow;
case 1: {
LoadInst *LI = new LoadInst(ShadowAddr, "", Pos);
LI->setAlignment(ShadowAlign);
return LI;
}
case 2: {
IRBuilder<> IRB(Pos);
Value *ShadowAddr1 = IRB.CreateGEP(DFS.ShadowTy, ShadowAddr,
ConstantInt::get(DFS.IntptrTy, 1));
return combineShadows(IRB.CreateAlignedLoad(ShadowAddr, ShadowAlign),
IRB.CreateAlignedLoad(ShadowAddr1, ShadowAlign), Pos);
}
}
if (!AvoidNewBlocks && Size % (64 / DFS.ShadowWidth) == 0) {
// Fast path for the common case where each byte has identical shadow: load
// shadow 64 bits at a time, fall out to a __dfsan_union_load call if any
// shadow is non-equal.
BasicBlock *FallbackBB = BasicBlock::Create(*DFS.Ctx, "", F);
IRBuilder<> FallbackIRB(FallbackBB);
CallInst *FallbackCall = FallbackIRB.CreateCall(
DFS.DFSanUnionLoadFn,
{ShadowAddr, ConstantInt::get(DFS.IntptrTy, Size)});
FallbackCall->addAttribute(AttributeSet::ReturnIndex, Attribute::ZExt);
// Compare each of the shadows stored in the loaded 64 bits to each other,
// by computing (WideShadow rotl ShadowWidth) == WideShadow.
IRBuilder<> IRB(Pos);
Value *WideAddr =
IRB.CreateBitCast(ShadowAddr, Type::getInt64PtrTy(*DFS.Ctx));
Value *WideShadow = IRB.CreateAlignedLoad(WideAddr, ShadowAlign);
Value *TruncShadow = IRB.CreateTrunc(WideShadow, DFS.ShadowTy);
Value *ShlShadow = IRB.CreateShl(WideShadow, DFS.ShadowWidth);
Value *ShrShadow = IRB.CreateLShr(WideShadow, 64 - DFS.ShadowWidth);
Value *RotShadow = IRB.CreateOr(ShlShadow, ShrShadow);
Value *ShadowsEq = IRB.CreateICmpEQ(WideShadow, RotShadow);
BasicBlock *Head = Pos->getParent();
BasicBlock *Tail = Head->splitBasicBlock(Pos);
if (DomTreeNode *OldNode = DT.getNode(Head)) {
std::vector<DomTreeNode *> Children(OldNode->begin(), OldNode->end());
DomTreeNode *NewNode = DT.addNewBlock(Tail, Head);
for (auto Child : Children)
DT.changeImmediateDominator(Child, NewNode);
}
// In the following code LastBr will refer to the previous basic block's
// conditional branch instruction, whose true successor is fixed up to point
// to the next block during the loop below or to the tail after the final
// iteration.
BranchInst *LastBr = BranchInst::Create(FallbackBB, FallbackBB, ShadowsEq);
ReplaceInstWithInst(Head->getTerminator(), LastBr);
DT.addNewBlock(FallbackBB, Head);
for (uint64_t Ofs = 64 / DFS.ShadowWidth; Ofs != Size;
Ofs += 64 / DFS.ShadowWidth) {
BasicBlock *NextBB = BasicBlock::Create(*DFS.Ctx, "", F);
DT.addNewBlock(NextBB, LastBr->getParent());
IRBuilder<> NextIRB(NextBB);
WideAddr = NextIRB.CreateGEP(Type::getInt64Ty(*DFS.Ctx), WideAddr,
ConstantInt::get(DFS.IntptrTy, 1));
Value *NextWideShadow = NextIRB.CreateAlignedLoad(WideAddr, ShadowAlign);
ShadowsEq = NextIRB.CreateICmpEQ(WideShadow, NextWideShadow);
LastBr->setSuccessor(0, NextBB);
LastBr = NextIRB.CreateCondBr(ShadowsEq, FallbackBB, FallbackBB);
}
LastBr->setSuccessor(0, Tail);
FallbackIRB.CreateBr(Tail);
PHINode *Shadow = PHINode::Create(DFS.ShadowTy, 2, "", &Tail->front());
Shadow->addIncoming(FallbackCall, FallbackBB);
Shadow->addIncoming(TruncShadow, LastBr->getParent());
return Shadow;
}
IRBuilder<> IRB(Pos);
CallInst *FallbackCall = IRB.CreateCall(
DFS.DFSanUnionLoadFn, {ShadowAddr, ConstantInt::get(DFS.IntptrTy, Size)});
FallbackCall->addAttribute(AttributeSet::ReturnIndex, Attribute::ZExt);
return FallbackCall;
}
void DFSanVisitor::visitLoadInst(LoadInst &LI) {
auto &DL = LI.getModule()->getDataLayout();
uint64_t Size = DL.getTypeStoreSize(LI.getType());
if (Size == 0) {
DFSF.setShadow(&LI, DFSF.DFS.ZeroShadow);
return;
}
uint64_t Align;
if (ClPreserveAlignment) {
Align = LI.getAlignment();
if (Align == 0)
Align = DL.getABITypeAlignment(LI.getType());
} else {
Align = 1;
}
IRBuilder<> IRB(&LI);
Value *Shadow = DFSF.loadShadow(LI.getPointerOperand(), Size, Align, &LI);
if (ClCombinePointerLabelsOnLoad) {
Value *PtrShadow = DFSF.getShadow(LI.getPointerOperand());
Shadow = DFSF.combineShadows(Shadow, PtrShadow, &LI);
}
if (Shadow != DFSF.DFS.ZeroShadow)
DFSF.NonZeroChecks.push_back(Shadow);
DFSF.setShadow(&LI, Shadow);
}
void DFSanFunction::storeShadow(Value *Addr, uint64_t Size, uint64_t Align,
Value *Shadow, Instruction *Pos) {
if (AllocaInst *AI = dyn_cast<AllocaInst>(Addr)) {
llvm::DenseMap<AllocaInst *, AllocaInst *>::iterator i =
AllocaShadowMap.find(AI);
if (i != AllocaShadowMap.end()) {
IRBuilder<> IRB(Pos);
IRB.CreateStore(Shadow, i->second);
return;
}
}
uint64_t ShadowAlign = Align * DFS.ShadowWidth / 8;
IRBuilder<> IRB(Pos);
Value *ShadowAddr = DFS.getShadowAddress(Addr, Pos);
if (Shadow == DFS.ZeroShadow) {
IntegerType *ShadowTy = IntegerType::get(*DFS.Ctx, Size * DFS.ShadowWidth);
Value *ExtZeroShadow = ConstantInt::get(ShadowTy, 0);
Value *ExtShadowAddr =
IRB.CreateBitCast(ShadowAddr, PointerType::getUnqual(ShadowTy));
IRB.CreateAlignedStore(ExtZeroShadow, ExtShadowAddr, ShadowAlign);
return;
}
const unsigned ShadowVecSize = 128 / DFS.ShadowWidth;
uint64_t Offset = 0;
if (Size >= ShadowVecSize) {
VectorType *ShadowVecTy = VectorType::get(DFS.ShadowTy, ShadowVecSize);
Value *ShadowVec = UndefValue::get(ShadowVecTy);
for (unsigned i = 0; i != ShadowVecSize; ++i) {
ShadowVec = IRB.CreateInsertElement(
ShadowVec, Shadow, ConstantInt::get(Type::getInt32Ty(*DFS.Ctx), i));
}
Value *ShadowVecAddr =
IRB.CreateBitCast(ShadowAddr, PointerType::getUnqual(ShadowVecTy));
do {
Value *CurShadowVecAddr =
IRB.CreateConstGEP1_32(ShadowVecTy, ShadowVecAddr, Offset);
IRB.CreateAlignedStore(ShadowVec, CurShadowVecAddr, ShadowAlign);
Size -= ShadowVecSize;
++Offset;
} while (Size >= ShadowVecSize);
Offset *= ShadowVecSize;
}
while (Size > 0) {
Value *CurShadowAddr =
IRB.CreateConstGEP1_32(DFS.ShadowTy, ShadowAddr, Offset);
IRB.CreateAlignedStore(Shadow, CurShadowAddr, ShadowAlign);
--Size;
++Offset;
}
}
void DFSanVisitor::visitStoreInst(StoreInst &SI) {
auto &DL = SI.getModule()->getDataLayout();
uint64_t Size = DL.getTypeStoreSize(SI.getValueOperand()->getType());
if (Size == 0)
return;
uint64_t Align;
if (ClPreserveAlignment) {
Align = SI.getAlignment();
if (Align == 0)
Align = DL.getABITypeAlignment(SI.getValueOperand()->getType());
} else {
Align = 1;
}
Value* Shadow = DFSF.getShadow(SI.getValueOperand());
if (ClCombinePointerLabelsOnStore) {
Value *PtrShadow = DFSF.getShadow(SI.getPointerOperand());
Shadow = DFSF.combineShadows(Shadow, PtrShadow, &SI);
}
DFSF.storeShadow(SI.getPointerOperand(), Size, Align, Shadow, &SI);
}
void DFSanVisitor::visitBinaryOperator(BinaryOperator &BO) {
visitOperandShadowInst(BO);
}
void DFSanVisitor::visitCastInst(CastInst &CI) { visitOperandShadowInst(CI); }
void DFSanVisitor::visitCmpInst(CmpInst &CI) { visitOperandShadowInst(CI); }
void DFSanVisitor::visitGetElementPtrInst(GetElementPtrInst &GEPI) {
visitOperandShadowInst(GEPI);
}
void DFSanVisitor::visitExtractElementInst(ExtractElementInst &I) {
visitOperandShadowInst(I);
}
void DFSanVisitor::visitInsertElementInst(InsertElementInst &I) {
visitOperandShadowInst(I);
}
void DFSanVisitor::visitShuffleVectorInst(ShuffleVectorInst &I) {
visitOperandShadowInst(I);
}
void DFSanVisitor::visitExtractValueInst(ExtractValueInst &I) {
visitOperandShadowInst(I);
}
void DFSanVisitor::visitInsertValueInst(InsertValueInst &I) {
visitOperandShadowInst(I);
}
void DFSanVisitor::visitAllocaInst(AllocaInst &I) {
bool AllLoadsStores = true;
for (User *U : I.users()) {
if (isa<LoadInst>(U))
continue;
if (StoreInst *SI = dyn_cast<StoreInst>(U)) {
if (SI->getPointerOperand() == &I)
continue;
}
AllLoadsStores = false;
break;
}
if (AllLoadsStores) {
IRBuilder<> IRB(&I);
DFSF.AllocaShadowMap[&I] = IRB.CreateAlloca(DFSF.DFS.ShadowTy);
}
DFSF.setShadow(&I, DFSF.DFS.ZeroShadow);
}
void DFSanVisitor::visitSelectInst(SelectInst &I) {
Value *CondShadow = DFSF.getShadow(I.getCondition());
Value *TrueShadow = DFSF.getShadow(I.getTrueValue());
Value *FalseShadow = DFSF.getShadow(I.getFalseValue());
if (isa<VectorType>(I.getCondition()->getType())) {
DFSF.setShadow(
&I,
DFSF.combineShadows(
CondShadow, DFSF.combineShadows(TrueShadow, FalseShadow, &I), &I));
} else {
Value *ShadowSel;
if (TrueShadow == FalseShadow) {
ShadowSel = TrueShadow;
} else {
ShadowSel =
SelectInst::Create(I.getCondition(), TrueShadow, FalseShadow, "", &I);
}
DFSF.setShadow(&I, DFSF.combineShadows(CondShadow, ShadowSel, &I));
}
}
void DFSanVisitor::visitMemSetInst(MemSetInst &I) {
IRBuilder<> IRB(&I);
Value *ValShadow = DFSF.getShadow(I.getValue());
IRB.CreateCall(DFSF.DFS.DFSanSetLabelFn,
{ValShadow, IRB.CreateBitCast(I.getDest(), Type::getInt8PtrTy(
*DFSF.DFS.Ctx)),
IRB.CreateZExtOrTrunc(I.getLength(), DFSF.DFS.IntptrTy)});
}
void DFSanVisitor::visitMemTransferInst(MemTransferInst &I) {
IRBuilder<> IRB(&I);
Value *DestShadow = DFSF.DFS.getShadowAddress(I.getDest(), &I);
Value *SrcShadow = DFSF.DFS.getShadowAddress(I.getSource(), &I);
Value *LenShadow = IRB.CreateMul(
I.getLength(),
ConstantInt::get(I.getLength()->getType(), DFSF.DFS.ShadowWidth / 8));
Value *AlignShadow;
if (ClPreserveAlignment) {
AlignShadow = IRB.CreateMul(I.getAlignmentCst(),
ConstantInt::get(I.getAlignmentCst()->getType(),
DFSF.DFS.ShadowWidth / 8));
} else {
AlignShadow = ConstantInt::get(I.getAlignmentCst()->getType(),
DFSF.DFS.ShadowWidth / 8);
}
Type *Int8Ptr = Type::getInt8PtrTy(*DFSF.DFS.Ctx);
DestShadow = IRB.CreateBitCast(DestShadow, Int8Ptr);
SrcShadow = IRB.CreateBitCast(SrcShadow, Int8Ptr);
IRB.CreateCall(I.getCalledValue(), {DestShadow, SrcShadow, LenShadow,
AlignShadow, I.getVolatileCst()});
}
void DFSanVisitor::visitReturnInst(ReturnInst &RI) {
if (!DFSF.IsNativeABI && RI.getReturnValue()) {
switch (DFSF.IA) {
case DataFlowSanitizer::IA_TLS: {
Value *S = DFSF.getShadow(RI.getReturnValue());
IRBuilder<> IRB(&RI);
IRB.CreateStore(S, DFSF.getRetvalTLS());
break;
}
case DataFlowSanitizer::IA_Args: {
IRBuilder<> IRB(&RI);
Type *RT = DFSF.F->getFunctionType()->getReturnType();
Value *InsVal =
IRB.CreateInsertValue(UndefValue::get(RT), RI.getReturnValue(), 0);
Value *InsShadow =
IRB.CreateInsertValue(InsVal, DFSF.getShadow(RI.getReturnValue()), 1);
RI.setOperand(0, InsShadow);
break;
}
}
}
}
void DFSanVisitor::visitCallSite(CallSite CS) {
Function *F = CS.getCalledFunction();
if ((F && F->isIntrinsic()) || isa<InlineAsm>(CS.getCalledValue())) {
visitOperandShadowInst(*CS.getInstruction());
return;
}
// Calls to this function are synthesized in wrappers, and we shouldn't
// instrument them.
if (F == DFSF.DFS.DFSanVarargWrapperFn)
return;
assert(!(cast<FunctionType>(
CS.getCalledValue()->getType()->getPointerElementType())->isVarArg() &&
dyn_cast<InvokeInst>(CS.getInstruction())));
IRBuilder<> IRB(CS.getInstruction());
DenseMap<Value *, Function *>::iterator i =
DFSF.DFS.UnwrappedFnMap.find(CS.getCalledValue());
if (i != DFSF.DFS.UnwrappedFnMap.end()) {
Function *F = i->second;
switch (DFSF.DFS.getWrapperKind(F)) {
case DataFlowSanitizer::WK_Warning: {
CS.setCalledFunction(F);
IRB.CreateCall(DFSF.DFS.DFSanUnimplementedFn,
IRB.CreateGlobalStringPtr(F->getName()));
DFSF.setShadow(CS.getInstruction(), DFSF.DFS.ZeroShadow);
return;
}
case DataFlowSanitizer::WK_Discard: {
CS.setCalledFunction(F);
DFSF.setShadow(CS.getInstruction(), DFSF.DFS.ZeroShadow);
return;
}
case DataFlowSanitizer::WK_Functional: {
CS.setCalledFunction(F);
visitOperandShadowInst(*CS.getInstruction());
return;
}
case DataFlowSanitizer::WK_Custom: {
// Don't try to handle invokes of custom functions, it's too complicated.
// Instead, invoke the dfsw$ wrapper, which will in turn call the __dfsw_
// wrapper.
if (CallInst *CI = dyn_cast<CallInst>(CS.getInstruction())) {
FunctionType *FT = F->getFunctionType();
FunctionType *CustomFT = DFSF.DFS.getCustomFunctionType(FT);
std::string CustomFName = "__dfsw_";
CustomFName += F->getName();
Constant *CustomF =
DFSF.DFS.Mod->getOrInsertFunction(CustomFName, CustomFT);
if (Function *CustomFn = dyn_cast<Function>(CustomF)) {
CustomFn->copyAttributesFrom(F);
// Custom functions returning non-void will write to the return label.
if (!FT->getReturnType()->isVoidTy()) {
CustomFn->removeAttributes(AttributeSet::FunctionIndex,
DFSF.DFS.ReadOnlyNoneAttrs);
}
}
std::vector<Value *> Args;
CallSite::arg_iterator i = CS.arg_begin();
for (unsigned n = FT->getNumParams(); n != 0; ++i, --n) {
Type *T = (*i)->getType();
FunctionType *ParamFT;
if (isa<PointerType>(T) &&
(ParamFT = dyn_cast<FunctionType>(
cast<PointerType>(T)->getElementType()))) {
std::string TName = "dfst";
TName += utostr(FT->getNumParams() - n);
TName += "$";
TName += F->getName();
Constant *T = DFSF.DFS.getOrBuildTrampolineFunction(ParamFT, TName);
Args.push_back(T);
Args.push_back(
IRB.CreateBitCast(*i, Type::getInt8PtrTy(*DFSF.DFS.Ctx)));
} else {
Args.push_back(*i);
}
}
i = CS.arg_begin();
for (unsigned n = FT->getNumParams(); n != 0; ++i, --n)
Args.push_back(DFSF.getShadow(*i));
if (FT->isVarArg()) {
auto *LabelVATy = ArrayType::get(DFSF.DFS.ShadowTy,
CS.arg_size() - FT->getNumParams());
auto *LabelVAAlloca = new AllocaInst(LabelVATy, "labelva",
DFSF.F->getEntryBlock().begin());
for (unsigned n = 0; i != CS.arg_end(); ++i, ++n) {
auto LabelVAPtr = IRB.CreateStructGEP(LabelVATy, LabelVAAlloca, n);
IRB.CreateStore(DFSF.getShadow(*i), LabelVAPtr);
}
Args.push_back(IRB.CreateStructGEP(LabelVATy, LabelVAAlloca, 0));
}
if (!FT->getReturnType()->isVoidTy()) {
if (!DFSF.LabelReturnAlloca) {
DFSF.LabelReturnAlloca =
new AllocaInst(DFSF.DFS.ShadowTy, "labelreturn",
DFSF.F->getEntryBlock().begin());
}
Args.push_back(DFSF.LabelReturnAlloca);
}
for (i = CS.arg_begin() + FT->getNumParams(); i != CS.arg_end(); ++i)
Args.push_back(*i);
CallInst *CustomCI = IRB.CreateCall(CustomF, Args);
CustomCI->setCallingConv(CI->getCallingConv());
CustomCI->setAttributes(CI->getAttributes());
if (!FT->getReturnType()->isVoidTy()) {
LoadInst *LabelLoad = IRB.CreateLoad(DFSF.LabelReturnAlloca);
DFSF.setShadow(CustomCI, LabelLoad);
}
CI->replaceAllUsesWith(CustomCI);
CI->eraseFromParent();
return;
}
break;
}
}
}
FunctionType *FT = cast<FunctionType>(
CS.getCalledValue()->getType()->getPointerElementType());
if (DFSF.DFS.getInstrumentedABI() == DataFlowSanitizer::IA_TLS) {
for (unsigned i = 0, n = FT->getNumParams(); i != n; ++i) {
IRB.CreateStore(DFSF.getShadow(CS.getArgument(i)),
DFSF.getArgTLS(i, CS.getInstruction()));
}
}
Instruction *Next = nullptr;
if (!CS.getType()->isVoidTy()) {
if (InvokeInst *II = dyn_cast<InvokeInst>(CS.getInstruction())) {
if (II->getNormalDest()->getSinglePredecessor()) {
Next = II->getNormalDest()->begin();
} else {
BasicBlock *NewBB =
SplitEdge(II->getParent(), II->getNormalDest(), &DFSF.DT);
Next = NewBB->begin();
}
} else {
Next = CS->getNextNode();
}
if (DFSF.DFS.getInstrumentedABI() == DataFlowSanitizer::IA_TLS) {
IRBuilder<> NextIRB(Next);
LoadInst *LI = NextIRB.CreateLoad(DFSF.getRetvalTLS());
DFSF.SkipInsts.insert(LI);
DFSF.setShadow(CS.getInstruction(), LI);
DFSF.NonZeroChecks.push_back(LI);
}
}
// Do all instrumentation for IA_Args down here to defer tampering with the
// CFG in a way that SplitEdge may be able to detect.
if (DFSF.DFS.getInstrumentedABI() == DataFlowSanitizer::IA_Args) {
FunctionType *NewFT = DFSF.DFS.getArgsFunctionType(FT);
Value *Func =
IRB.CreateBitCast(CS.getCalledValue(), PointerType::getUnqual(NewFT));
std::vector<Value *> Args;
CallSite::arg_iterator i = CS.arg_begin(), e = CS.arg_end();
for (unsigned n = FT->getNumParams(); n != 0; ++i, --n)
Args.push_back(*i);
i = CS.arg_begin();
for (unsigned n = FT->getNumParams(); n != 0; ++i, --n)
Args.push_back(DFSF.getShadow(*i));
if (FT->isVarArg()) {
unsigned VarArgSize = CS.arg_size() - FT->getNumParams();
ArrayType *VarArgArrayTy = ArrayType::get(DFSF.DFS.ShadowTy, VarArgSize);
AllocaInst *VarArgShadow =
new AllocaInst(VarArgArrayTy, "", DFSF.F->getEntryBlock().begin());
Args.push_back(IRB.CreateConstGEP2_32(VarArgArrayTy, VarArgShadow, 0, 0));
for (unsigned n = 0; i != e; ++i, ++n) {
IRB.CreateStore(
DFSF.getShadow(*i),
IRB.CreateConstGEP2_32(VarArgArrayTy, VarArgShadow, 0, n));
Args.push_back(*i);
}
}
CallSite NewCS;
if (InvokeInst *II = dyn_cast<InvokeInst>(CS.getInstruction())) {
NewCS = IRB.CreateInvoke(Func, II->getNormalDest(), II->getUnwindDest(),
Args);
} else {
NewCS = IRB.CreateCall(Func, Args);
}
NewCS.setCallingConv(CS.getCallingConv());
NewCS.setAttributes(CS.getAttributes().removeAttributes(
*DFSF.DFS.Ctx, AttributeSet::ReturnIndex,
AttributeFuncs::typeIncompatible(NewCS.getInstruction()->getType())));
if (Next) {
ExtractValueInst *ExVal =
ExtractValueInst::Create(NewCS.getInstruction(), 0, "", Next);
DFSF.SkipInsts.insert(ExVal);
ExtractValueInst *ExShadow =
ExtractValueInst::Create(NewCS.getInstruction(), 1, "", Next);
DFSF.SkipInsts.insert(ExShadow);
DFSF.setShadow(ExVal, ExShadow);
DFSF.NonZeroChecks.push_back(ExShadow);
CS.getInstruction()->replaceAllUsesWith(ExVal);
}
CS.getInstruction()->eraseFromParent();
}
}
void DFSanVisitor::visitPHINode(PHINode &PN) {
PHINode *ShadowPN =
PHINode::Create(DFSF.DFS.ShadowTy, PN.getNumIncomingValues(), "", &PN);
// Give the shadow phi node valid predecessors to fool SplitEdge into working.
Value *UndefShadow = UndefValue::get(DFSF.DFS.ShadowTy);
for (PHINode::block_iterator i = PN.block_begin(), e = PN.block_end(); i != e;
++i) {
ShadowPN->addIncoming(UndefShadow, *i);
}
DFSF.PHIFixups.push_back(std::make_pair(&PN, ShadowPN));
DFSF.setShadow(&PN, ShadowPN);
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Instrumentation/CMakeLists.txt | add_llvm_library(LLVMInstrumentation
AddressSanitizer.cpp
BoundsChecking.cpp
DataFlowSanitizer.cpp
GCOVProfiling.cpp
MemorySanitizer.cpp
Instrumentation.cpp
InstrProfiling.cpp
SafeStack.cpp
SanitizerCoverage.cpp
ThreadSanitizer.cpp
ADDITIONAL_HEADER_DIRS
${LLVM_MAIN_INCLUDE_DIR}/llvm/Transforms
)
add_dependencies(LLVMInstrumentation intrinsics_gen)
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Instrumentation/MaximumSpanningTree.h | //===- llvm/Analysis/MaximumSpanningTree.h - Interface ----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This module provides means for calculating a maximum spanning tree for a
// given set of weighted edges. The type parameter T is the type of a node.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ANALYSIS_MAXIMUMSPANNINGTREE_H
#define LLVM_ANALYSIS_MAXIMUMSPANNINGTREE_H
#include "llvm/ADT/EquivalenceClasses.h"
#include "llvm/IR/BasicBlock.h"
#include <algorithm>
#include <vector>
namespace llvm {
/// MaximumSpanningTree - A MST implementation.
/// The type parameter T determines the type of the nodes of the graph.
template <typename T>
class MaximumSpanningTree {
public:
typedef std::pair<const T*, const T*> Edge;
typedef std::pair<Edge, double> EdgeWeight;
typedef std::vector<EdgeWeight> EdgeWeights;
protected:
typedef std::vector<Edge> MaxSpanTree;
MaxSpanTree MST;
private:
// A comparing class for comparing weighted edges.
struct EdgeWeightCompare {
static bool getBlockSize(const T *X) {
const BasicBlock *BB = dyn_cast_or_null<BasicBlock>(X);
return BB ? BB->size() : 0;
}
bool operator()(EdgeWeight X, EdgeWeight Y) const {
if (X.second > Y.second) return true;
if (X.second < Y.second) return false;
// Equal edge weights: break ties by comparing block sizes.
size_t XSizeA = getBlockSize(X.first.first);
size_t YSizeA = getBlockSize(Y.first.first);
if (XSizeA > YSizeA) return true;
if (XSizeA < YSizeA) return false;
size_t XSizeB = getBlockSize(X.first.second);
size_t YSizeB = getBlockSize(Y.first.second);
if (XSizeB > YSizeB) return true;
if (XSizeB < YSizeB) return false;
return false;
}
};
public:
static char ID; // Class identification, replacement for typeinfo
/// MaximumSpanningTree() - Takes a vector of weighted edges and returns a
/// spanning tree.
MaximumSpanningTree(EdgeWeights &EdgeVector) {
std::stable_sort(EdgeVector.begin(), EdgeVector.end(), EdgeWeightCompare());
// Create spanning tree, Forest contains a special data structure
// that makes checking if two nodes are already in a common (sub-)tree
// fast and cheap.
EquivalenceClasses<const T*> Forest;
for (typename EdgeWeights::iterator EWi = EdgeVector.begin(),
EWe = EdgeVector.end(); EWi != EWe; ++EWi) {
Edge e = (*EWi).first;
Forest.insert(e.first);
Forest.insert(e.second);
}
// Iterate over the sorted edges, biggest first.
for (typename EdgeWeights::iterator EWi = EdgeVector.begin(),
EWe = EdgeVector.end(); EWi != EWe; ++EWi) {
Edge e = (*EWi).first;
if (Forest.findLeader(e.first) != Forest.findLeader(e.second)) {
Forest.unionSets(e.first, e.second);
// So we know now that the edge is not already in a subtree, so we push
// the edge to the MST.
MST.push_back(e);
}
}
}
typename MaxSpanTree::iterator begin() {
return MST.begin();
}
typename MaxSpanTree::iterator end() {
return MST.end();
}
};
} // End llvm namespace
#endif
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Instrumentation/LLVMBuild.txt | ;===- ./lib/Transforms/Instrumentation/LLVMBuild.txt -----------*- Conf -*--===;
;
; The LLVM Compiler Infrastructure
;
; This file is distributed under the University of Illinois Open Source
; License. See LICENSE.TXT for details.
;
;===------------------------------------------------------------------------===;
;
; This is an LLVMBuild description file for the components in this subdirectory.
;
; For more information on the LLVMBuild system, please see:
;
; http://llvm.org/docs/LLVMBuild.html
;
;===------------------------------------------------------------------------===;
[component_0]
type = Library
name = Instrumentation
parent = Transforms
required_libraries = Analysis Core Support TransformUtils
; MC - HLSL Change |
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Instrumentation/GCOVProfiling.cpp | //===- GCOVProfiling.cpp - Insert edge counters for gcov profiling --------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This pass implements GCOV-style profiling. When this pass is run it emits
// "gcno" files next to the existing source, and instruments the code that runs
// to records the edges between blocks that run and emit a complementary "gcda"
// file on exit.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Instrumentation.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/Hashing.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/UniqueVector.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/DebugLoc.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InstIterator.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/ModuleUtils.h"
#include <algorithm>
#include <memory>
#include <string>
#include <utility>
using namespace llvm;
#define DEBUG_TYPE "insert-gcov-profiling"
static cl::opt<std::string>
DefaultGCOVVersion("default-gcov-version", cl::init("402*"), cl::Hidden,
cl::ValueRequired);
static cl::opt<bool> DefaultExitBlockBeforeBody("gcov-exit-block-before-body",
cl::init(false), cl::Hidden);
GCOVOptions GCOVOptions::getDefault() {
GCOVOptions Options;
Options.EmitNotes = true;
Options.EmitData = true;
Options.UseCfgChecksum = false;
Options.NoRedZone = false;
Options.FunctionNamesInData = true;
Options.ExitBlockBeforeBody = DefaultExitBlockBeforeBody;
if (DefaultGCOVVersion.size() != 4) {
llvm::report_fatal_error(std::string("Invalid -default-gcov-version: ") +
DefaultGCOVVersion);
}
memcpy(Options.Version, DefaultGCOVVersion.c_str(), 4);
return Options;
}
namespace {
class GCOVFunction;
class GCOVProfiler : public ModulePass {
public:
static char ID;
GCOVProfiler() : GCOVProfiler(GCOVOptions::getDefault()) {}
GCOVProfiler(const GCOVOptions &Opts) : ModulePass(ID), Options(Opts) {
assert((Options.EmitNotes || Options.EmitData) &&
"GCOVProfiler asked to do nothing?");
ReversedVersion[0] = Options.Version[3];
ReversedVersion[1] = Options.Version[2];
ReversedVersion[2] = Options.Version[1];
ReversedVersion[3] = Options.Version[0];
ReversedVersion[4] = '\0';
initializeGCOVProfilerPass(*PassRegistry::getPassRegistry());
}
StringRef getPassName() const override {
return "GCOV Profiler";
}
private:
bool runOnModule(Module &M) override;
// Create the .gcno files for the Module based on DebugInfo.
void emitProfileNotes();
// Modify the program to track transitions along edges and call into the
// profiling runtime to emit .gcda files when run.
bool emitProfileArcs();
// Get pointers to the functions in the runtime library.
Constant *getStartFileFunc();
Constant *getIncrementIndirectCounterFunc();
Constant *getEmitFunctionFunc();
Constant *getEmitArcsFunc();
Constant *getSummaryInfoFunc();
Constant *getDeleteWriteoutFunctionListFunc();
Constant *getDeleteFlushFunctionListFunc();
Constant *getEndFileFunc();
// Create or retrieve an i32 state value that is used to represent the
// pred block number for certain non-trivial edges.
GlobalVariable *getEdgeStateValue();
// Produce a table of pointers to counters, by predecessor and successor
// block number.
GlobalVariable *buildEdgeLookupTable(Function *F,
GlobalVariable *Counter,
const UniqueVector<BasicBlock *>&Preds,
const UniqueVector<BasicBlock*>&Succs);
// Add the function to write out all our counters to the global destructor
// list.
Function *insertCounterWriteout(ArrayRef<std::pair<GlobalVariable*,
MDNode*> >);
Function *insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> >);
void insertIndirectCounterIncrement();
std::string mangleName(const DICompileUnit *CU, const char *NewStem);
GCOVOptions Options;
// Reversed, NUL-terminated copy of Options.Version.
char ReversedVersion[5];
// Checksum, produced by hash of EdgeDestinations
SmallVector<uint32_t, 4> FileChecksums;
Module *M;
LLVMContext *Ctx;
SmallVector<std::unique_ptr<GCOVFunction>, 16> Funcs;
};
}
char GCOVProfiler::ID = 0;
INITIALIZE_PASS(GCOVProfiler, "insert-gcov-profiling",
"Insert instrumentation for GCOV profiling", false, false)
ModulePass *llvm::createGCOVProfilerPass(const GCOVOptions &Options) {
return new GCOVProfiler(Options);
}
static StringRef getFunctionName(const DISubprogram *SP) {
if (!SP->getLinkageName().empty())
return SP->getLinkageName();
return SP->getName();
}
namespace {
class GCOVRecord {
protected:
static const char *const LinesTag;
static const char *const FunctionTag;
static const char *const BlockTag;
static const char *const EdgeTag;
GCOVRecord() = default;
void writeBytes(const char *Bytes, int Size) {
os->write(Bytes, Size);
}
void write(uint32_t i) {
writeBytes(reinterpret_cast<char*>(&i), 4);
}
// Returns the length measured in 4-byte blocks that will be used to
// represent this string in a GCOV file
static unsigned lengthOfGCOVString(StringRef s) {
// A GCOV string is a length, followed by a NUL, then between 0 and 3 NULs
// padding out to the next 4-byte word. The length is measured in 4-byte
// words including padding, not bytes of actual string.
return (s.size() / 4) + 1;
}
void writeGCOVString(StringRef s) {
uint32_t Len = lengthOfGCOVString(s);
write(Len);
writeBytes(s.data(), s.size());
// Write 1 to 4 bytes of NUL padding.
assert((unsigned)(4 - (s.size() % 4)) > 0);
assert((unsigned)(4 - (s.size() % 4)) <= 4);
writeBytes("\0\0\0\0", 4 - (s.size() % 4));
}
raw_ostream *os;
};
const char *const GCOVRecord::LinesTag = "\0\0\x45\x01";
const char *const GCOVRecord::FunctionTag = "\0\0\0\1";
const char *const GCOVRecord::BlockTag = "\0\0\x41\x01";
const char *const GCOVRecord::EdgeTag = "\0\0\x43\x01";
class GCOVFunction;
class GCOVBlock;
// Constructed only by requesting it from a GCOVBlock, this object stores a
// list of line numbers and a single filename, representing lines that belong
// to the block.
class GCOVLines : public GCOVRecord {
public:
void addLine(uint32_t Line) {
assert(Line != 0 && "Line zero is not a valid real line number.");
Lines.push_back(Line);
}
uint32_t length() const {
// Here 2 = 1 for string length + 1 for '0' id#.
return lengthOfGCOVString(Filename) + 2 + Lines.size();
}
void writeOut() {
write(0);
writeGCOVString(Filename);
for (int i = 0, e = Lines.size(); i != e; ++i)
write(Lines[i]);
}
GCOVLines(StringRef F, raw_ostream *os)
: Filename(F) {
this->os = os;
}
private:
StringRef Filename;
SmallVector<uint32_t, 32> Lines;
};
// Represent a basic block in GCOV. Each block has a unique number in the
// function, number of lines belonging to each block, and a set of edges to
// other blocks.
class GCOVBlock : public GCOVRecord {
public:
GCOVLines &getFile(StringRef Filename) {
GCOVLines *&Lines = LinesByFile[Filename];
if (!Lines) {
Lines = new GCOVLines(Filename, os);
}
return *Lines;
}
void addEdge(GCOVBlock &Successor) {
OutEdges.push_back(&Successor);
}
void writeOut() {
uint32_t Len = 3;
SmallVector<StringMapEntry<GCOVLines *> *, 32> SortedLinesByFile;
for (StringMap<GCOVLines *>::iterator I = LinesByFile.begin(),
E = LinesByFile.end(); I != E; ++I) {
Len += I->second->length();
SortedLinesByFile.push_back(&*I);
}
writeBytes(LinesTag, 4);
write(Len);
write(Number);
std::sort(SortedLinesByFile.begin(), SortedLinesByFile.end(),
[](StringMapEntry<GCOVLines *> *LHS,
StringMapEntry<GCOVLines *> *RHS) {
return LHS->getKey() < RHS->getKey();
});
for (SmallVectorImpl<StringMapEntry<GCOVLines *> *>::iterator
I = SortedLinesByFile.begin(), E = SortedLinesByFile.end();
I != E; ++I)
(*I)->getValue()->writeOut();
write(0);
write(0);
}
~GCOVBlock() {
DeleteContainerSeconds(LinesByFile);
}
GCOVBlock(const GCOVBlock &RHS) : GCOVRecord(RHS), Number(RHS.Number) {
// Only allow copy before edges and lines have been added. After that,
// there are inter-block pointers (eg: edges) that won't take kindly to
// blocks being copied or moved around.
assert(LinesByFile.empty());
assert(OutEdges.empty());
}
private:
friend class GCOVFunction;
GCOVBlock(uint32_t Number, raw_ostream *os)
: Number(Number) {
this->os = os;
}
uint32_t Number;
StringMap<GCOVLines *> LinesByFile;
SmallVector<GCOVBlock *, 4> OutEdges;
};
// A function has a unique identifier, a checksum (we leave as zero) and a
// set of blocks and a map of edges between blocks. This is the only GCOV
// object users can construct, the blocks and lines will be rooted here.
class GCOVFunction : public GCOVRecord {
public:
GCOVFunction(const DISubprogram *SP, raw_ostream *os, uint32_t Ident,
bool UseCfgChecksum, bool ExitBlockBeforeBody)
: SP(SP), Ident(Ident), UseCfgChecksum(UseCfgChecksum), CfgChecksum(0),
ReturnBlock(1, os) {
this->os = os;
Function *F = SP->getFunction();
DEBUG(dbgs() << "Function: " << getFunctionName(SP) << "\n");
uint32_t i = 0;
for (auto &BB : *F) {
// Skip index 1 if it's assigned to the ReturnBlock.
if (i == 1 && ExitBlockBeforeBody)
++i;
Blocks.insert(std::make_pair(&BB, GCOVBlock(i++, os)));
}
if (!ExitBlockBeforeBody)
ReturnBlock.Number = i;
std::string FunctionNameAndLine;
raw_string_ostream FNLOS(FunctionNameAndLine);
FNLOS << getFunctionName(SP) << SP->getLine();
FNLOS.flush();
FuncChecksum = hash_value(FunctionNameAndLine);
}
GCOVBlock &getBlock(BasicBlock *BB) {
return Blocks.find(BB)->second;
}
GCOVBlock &getReturnBlock() {
return ReturnBlock;
}
std::string getEdgeDestinations() {
std::string EdgeDestinations;
raw_string_ostream EDOS(EdgeDestinations);
Function *F = Blocks.begin()->first->getParent();
for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
GCOVBlock &Block = getBlock(I);
for (int i = 0, e = Block.OutEdges.size(); i != e; ++i)
EDOS << Block.OutEdges[i]->Number;
}
return EdgeDestinations;
}
uint32_t getFuncChecksum() {
return FuncChecksum;
}
void setCfgChecksum(uint32_t Checksum) {
CfgChecksum = Checksum;
}
void writeOut() {
writeBytes(FunctionTag, 4);
uint32_t BlockLen = 1 + 1 + 1 + lengthOfGCOVString(getFunctionName(SP)) +
1 + lengthOfGCOVString(SP->getFilename()) + 1;
if (UseCfgChecksum)
++BlockLen;
write(BlockLen);
write(Ident);
write(FuncChecksum);
if (UseCfgChecksum)
write(CfgChecksum);
writeGCOVString(getFunctionName(SP));
writeGCOVString(SP->getFilename());
write(SP->getLine());
// Emit count of blocks.
writeBytes(BlockTag, 4);
write(Blocks.size() + 1);
for (int i = 0, e = Blocks.size() + 1; i != e; ++i) {
write(0); // No flags on our blocks.
}
DEBUG(dbgs() << Blocks.size() << " blocks.\n");
// Emit edges between blocks.
if (Blocks.empty()) return;
Function *F = Blocks.begin()->first->getParent();
for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
GCOVBlock &Block = getBlock(I);
if (Block.OutEdges.empty()) continue;
writeBytes(EdgeTag, 4);
write(Block.OutEdges.size() * 2 + 1);
write(Block.Number);
for (int i = 0, e = Block.OutEdges.size(); i != e; ++i) {
DEBUG(dbgs() << Block.Number << " -> " << Block.OutEdges[i]->Number
<< "\n");
write(Block.OutEdges[i]->Number);
write(0); // no flags
}
}
// Emit lines for each block.
for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
getBlock(I).writeOut();
}
}
private:
const DISubprogram *SP;
uint32_t Ident;
uint32_t FuncChecksum;
bool UseCfgChecksum;
uint32_t CfgChecksum;
DenseMap<BasicBlock *, GCOVBlock> Blocks;
GCOVBlock ReturnBlock;
};
}
std::string GCOVProfiler::mangleName(const DICompileUnit *CU,
const char *NewStem) {
if (NamedMDNode *GCov = M->getNamedMetadata("llvm.gcov")) {
for (int i = 0, e = GCov->getNumOperands(); i != e; ++i) {
MDNode *N = GCov->getOperand(i);
if (N->getNumOperands() != 2) continue;
MDString *GCovFile = dyn_cast<MDString>(N->getOperand(0));
MDNode *CompileUnit = dyn_cast<MDNode>(N->getOperand(1));
if (!GCovFile || !CompileUnit) continue;
if (CompileUnit == CU) {
SmallString<128> Filename = GCovFile->getString();
sys::path::replace_extension(Filename, NewStem);
return Filename.str();
}
}
}
SmallString<128> Filename = CU->getFilename();
sys::path::replace_extension(Filename, NewStem);
StringRef FName = sys::path::filename(Filename);
SmallString<128> CurPath;
if (sys::fs::current_path(CurPath)) return FName;
sys::path::append(CurPath, FName);
return CurPath.str();
}
bool GCOVProfiler::runOnModule(Module &M) {
this->M = &M;
Ctx = &M.getContext();
if (Options.EmitNotes) emitProfileNotes();
if (Options.EmitData) return emitProfileArcs();
return false;
}
static bool functionHasLines(Function *F) {
// Check whether this function actually has any source lines. Not only
// do these waste space, they also can crash gcov.
for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
for (BasicBlock::iterator I = BB->begin(), IE = BB->end();
I != IE; ++I) {
// Debug intrinsic locations correspond to the location of the
// declaration, not necessarily any statements or expressions.
if (isa<DbgInfoIntrinsic>(I)) continue;
const DebugLoc &Loc = I->getDebugLoc();
if (!Loc)
continue;
// Artificial lines such as calls to the global constructors.
if (Loc.getLine() == 0) continue;
return true;
}
}
return false;
}
void GCOVProfiler::emitProfileNotes() {
NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
if (!CU_Nodes) return;
for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
// Each compile unit gets its own .gcno file. This means that whether we run
// this pass over the original .o's as they're produced, or run it after
// LTO, we'll generate the same .gcno files.
auto *CU = cast<DICompileUnit>(CU_Nodes->getOperand(i));
std::error_code EC;
raw_fd_ostream out(mangleName(CU, "gcno"), EC, sys::fs::F_None);
std::string EdgeDestinations;
unsigned FunctionIdent = 0;
for (auto *SP : CU->getSubprograms()) {
Function *F = SP->getFunction();
if (!F) continue;
if (!functionHasLines(F)) continue;
// gcov expects every function to start with an entry block that has a
// single successor, so split the entry block to make sure of that.
BasicBlock &EntryBlock = F->getEntryBlock();
BasicBlock::iterator It = EntryBlock.begin();
while (isa<AllocaInst>(*It) || isa<DbgInfoIntrinsic>(*It))
++It;
EntryBlock.splitBasicBlock(It);
Funcs.push_back(make_unique<GCOVFunction>(SP, &out, FunctionIdent++,
Options.UseCfgChecksum,
Options.ExitBlockBeforeBody));
GCOVFunction &Func = *Funcs.back();
for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
GCOVBlock &Block = Func.getBlock(BB);
TerminatorInst *TI = BB->getTerminator();
if (int successors = TI->getNumSuccessors()) {
for (int i = 0; i != successors; ++i) {
Block.addEdge(Func.getBlock(TI->getSuccessor(i)));
}
} else if (isa<ReturnInst>(TI)) {
Block.addEdge(Func.getReturnBlock());
}
uint32_t Line = 0;
for (BasicBlock::iterator I = BB->begin(), IE = BB->end();
I != IE; ++I) {
// Debug intrinsic locations correspond to the location of the
// declaration, not necessarily any statements or expressions.
if (isa<DbgInfoIntrinsic>(I)) continue;
const DebugLoc &Loc = I->getDebugLoc();
if (!Loc)
continue;
// Artificial lines such as calls to the global constructors.
if (Loc.getLine() == 0) continue;
if (Line == Loc.getLine()) continue;
Line = Loc.getLine();
if (SP != getDISubprogram(Loc.getScope()))
continue;
GCOVLines &Lines = Block.getFile(SP->getFilename());
Lines.addLine(Loc.getLine());
}
}
EdgeDestinations += Func.getEdgeDestinations();
}
FileChecksums.push_back(hash_value(EdgeDestinations));
out.write("oncg", 4);
out.write(ReversedVersion, 4);
out.write(reinterpret_cast<char*>(&FileChecksums.back()), 4);
for (auto &Func : Funcs) {
Func->setCfgChecksum(FileChecksums.back());
Func->writeOut();
}
out.write("\0\0\0\0\0\0\0\0", 8); // EOF
out.close();
}
}
bool GCOVProfiler::emitProfileArcs() {
NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
if (!CU_Nodes) return false;
bool Result = false;
bool InsertIndCounterIncrCode = false;
for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
auto *CU = cast<DICompileUnit>(CU_Nodes->getOperand(i));
SmallVector<std::pair<GlobalVariable *, MDNode *>, 8> CountersBySP;
for (auto *SP : CU->getSubprograms()) {
Function *F = SP->getFunction();
if (!F) continue;
if (!functionHasLines(F)) continue;
if (!Result) Result = true;
unsigned Edges = 0;
for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
TerminatorInst *TI = BB->getTerminator();
if (isa<ReturnInst>(TI))
++Edges;
else
Edges += TI->getNumSuccessors();
}
ArrayType *CounterTy =
ArrayType::get(Type::getInt64Ty(*Ctx), Edges);
GlobalVariable *Counters =
new GlobalVariable(*M, CounterTy, false,
GlobalValue::InternalLinkage,
Constant::getNullValue(CounterTy),
"__llvm_gcov_ctr");
CountersBySP.push_back(std::make_pair(Counters, SP));
UniqueVector<BasicBlock *> ComplexEdgePreds;
UniqueVector<BasicBlock *> ComplexEdgeSuccs;
unsigned Edge = 0;
for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
TerminatorInst *TI = BB->getTerminator();
int Successors = isa<ReturnInst>(TI) ? 1 : TI->getNumSuccessors();
if (Successors) {
if (Successors == 1) {
IRBuilder<> Builder(BB->getFirstInsertionPt());
Value *Counter = Builder.CreateConstInBoundsGEP2_64(Counters, 0,
Edge);
Value *Count = Builder.CreateLoad(Counter);
Count = Builder.CreateAdd(Count, Builder.getInt64(1));
Builder.CreateStore(Count, Counter);
} else if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
IRBuilder<> Builder(BI);
Value *Sel = Builder.CreateSelect(BI->getCondition(),
Builder.getInt64(Edge),
Builder.getInt64(Edge + 1));
SmallVector<Value *, 2> Idx;
Idx.push_back(Builder.getInt64(0));
Idx.push_back(Sel);
Value *Counter = Builder.CreateInBoundsGEP(Counters->getValueType(),
Counters, Idx);
Value *Count = Builder.CreateLoad(Counter);
Count = Builder.CreateAdd(Count, Builder.getInt64(1));
Builder.CreateStore(Count, Counter);
} else {
ComplexEdgePreds.insert(BB);
for (int i = 0; i != Successors; ++i)
ComplexEdgeSuccs.insert(TI->getSuccessor(i));
}
Edge += Successors;
}
}
if (!ComplexEdgePreds.empty()) {
GlobalVariable *EdgeTable =
buildEdgeLookupTable(F, Counters,
ComplexEdgePreds, ComplexEdgeSuccs);
GlobalVariable *EdgeState = getEdgeStateValue();
for (int i = 0, e = ComplexEdgePreds.size(); i != e; ++i) {
IRBuilder<> Builder(ComplexEdgePreds[i + 1]->getFirstInsertionPt());
Builder.CreateStore(Builder.getInt32(i), EdgeState);
}
for (int i = 0, e = ComplexEdgeSuccs.size(); i != e; ++i) {
// Call runtime to perform increment.
IRBuilder<> Builder(ComplexEdgeSuccs[i+1]->getFirstInsertionPt());
Value *CounterPtrArray =
Builder.CreateConstInBoundsGEP2_64(EdgeTable, 0,
i * ComplexEdgePreds.size());
// Build code to increment the counter.
InsertIndCounterIncrCode = true;
Builder.CreateCall(getIncrementIndirectCounterFunc(),
{EdgeState, CounterPtrArray});
}
}
}
Function *WriteoutF = insertCounterWriteout(CountersBySP);
Function *FlushF = insertFlush(CountersBySP);
// Create a small bit of code that registers the "__llvm_gcov_writeout" to
// be executed at exit and the "__llvm_gcov_flush" function to be executed
// when "__gcov_flush" is called.
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
Function *F = Function::Create(FTy, GlobalValue::InternalLinkage,
"__llvm_gcov_init", M);
F->setUnnamedAddr(true);
F->setLinkage(GlobalValue::InternalLinkage);
F->addFnAttr(Attribute::NoInline);
if (Options.NoRedZone)
F->addFnAttr(Attribute::NoRedZone);
BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", F);
IRBuilder<> Builder(BB);
FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
Type *Params[] = {
PointerType::get(FTy, 0),
PointerType::get(FTy, 0)
};
FTy = FunctionType::get(Builder.getVoidTy(), Params, false);
// Initialize the environment and register the local writeout and flush
// functions.
Constant *GCOVInit = M->getOrInsertFunction("llvm_gcov_init", FTy);
Builder.CreateCall(GCOVInit, {WriteoutF, FlushF});
Builder.CreateRetVoid();
appendToGlobalCtors(*M, F, 0);
}
if (InsertIndCounterIncrCode)
insertIndirectCounterIncrement();
return Result;
}
// All edges with successors that aren't branches are "complex", because it
// requires complex logic to pick which counter to update.
GlobalVariable *GCOVProfiler::buildEdgeLookupTable(
Function *F,
GlobalVariable *Counters,
const UniqueVector<BasicBlock *> &Preds,
const UniqueVector<BasicBlock *> &Succs) {
// TODO: support invoke, threads. We rely on the fact that nothing can modify
// the whole-Module pred edge# between the time we set it and the time we next
// read it. Threads and invoke make this untrue.
// emit [(succs * preds) x i64*], logically [succ x [pred x i64*]].
size_t TableSize = Succs.size() * Preds.size();
Type *Int64PtrTy = Type::getInt64PtrTy(*Ctx);
ArrayType *EdgeTableTy = ArrayType::get(Int64PtrTy, TableSize);
std::unique_ptr<Constant * []> EdgeTable(new Constant *[TableSize]);
Constant *NullValue = Constant::getNullValue(Int64PtrTy);
for (size_t i = 0; i != TableSize; ++i)
EdgeTable[i] = NullValue;
unsigned Edge = 0;
for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
TerminatorInst *TI = BB->getTerminator();
int Successors = isa<ReturnInst>(TI) ? 1 : TI->getNumSuccessors();
if (Successors > 1 && !isa<BranchInst>(TI) && !isa<ReturnInst>(TI)) {
for (int i = 0; i != Successors; ++i) {
BasicBlock *Succ = TI->getSuccessor(i);
IRBuilder<> Builder(Succ);
Value *Counter = Builder.CreateConstInBoundsGEP2_64(Counters, 0,
Edge + i);
EdgeTable[((Succs.idFor(Succ)-1) * Preds.size()) +
(Preds.idFor(BB)-1)] = cast<Constant>(Counter);
}
}
Edge += Successors;
}
GlobalVariable *EdgeTableGV =
new GlobalVariable(
*M, EdgeTableTy, true, GlobalValue::InternalLinkage,
ConstantArray::get(EdgeTableTy,
makeArrayRef(&EdgeTable[0],TableSize)),
"__llvm_gcda_edge_table");
EdgeTableGV->setUnnamedAddr(true);
return EdgeTableGV;
}
Constant *GCOVProfiler::getStartFileFunc() {
Type *Args[] = {
Type::getInt8PtrTy(*Ctx), // const char *orig_filename
Type::getInt8PtrTy(*Ctx), // const char version[4]
Type::getInt32Ty(*Ctx), // uint32_t checksum
};
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
return M->getOrInsertFunction("llvm_gcda_start_file", FTy);
}
Constant *GCOVProfiler::getIncrementIndirectCounterFunc() {
Type *Int32Ty = Type::getInt32Ty(*Ctx);
Type *Int64Ty = Type::getInt64Ty(*Ctx);
Type *Args[] = {
Int32Ty->getPointerTo(), // uint32_t *predecessor
Int64Ty->getPointerTo()->getPointerTo() // uint64_t **counters
};
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
return M->getOrInsertFunction("__llvm_gcov_indirect_counter_increment", FTy);
}
Constant *GCOVProfiler::getEmitFunctionFunc() {
Type *Args[] = {
Type::getInt32Ty(*Ctx), // uint32_t ident
Type::getInt8PtrTy(*Ctx), // const char *function_name
Type::getInt32Ty(*Ctx), // uint32_t func_checksum
Type::getInt8Ty(*Ctx), // uint8_t use_extra_checksum
Type::getInt32Ty(*Ctx), // uint32_t cfg_checksum
};
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
return M->getOrInsertFunction("llvm_gcda_emit_function", FTy);
}
Constant *GCOVProfiler::getEmitArcsFunc() {
Type *Args[] = {
Type::getInt32Ty(*Ctx), // uint32_t num_counters
Type::getInt64PtrTy(*Ctx), // uint64_t *counters
};
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
return M->getOrInsertFunction("llvm_gcda_emit_arcs", FTy);
}
Constant *GCOVProfiler::getSummaryInfoFunc() {
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
return M->getOrInsertFunction("llvm_gcda_summary_info", FTy);
}
Constant *GCOVProfiler::getDeleteWriteoutFunctionListFunc() {
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
return M->getOrInsertFunction("llvm_delete_writeout_function_list", FTy);
}
Constant *GCOVProfiler::getDeleteFlushFunctionListFunc() {
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
return M->getOrInsertFunction("llvm_delete_flush_function_list", FTy);
}
Constant *GCOVProfiler::getEndFileFunc() {
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
return M->getOrInsertFunction("llvm_gcda_end_file", FTy);
}
GlobalVariable *GCOVProfiler::getEdgeStateValue() {
GlobalVariable *GV = M->getGlobalVariable("__llvm_gcov_global_state_pred");
if (!GV) {
GV = new GlobalVariable(*M, Type::getInt32Ty(*Ctx), false,
GlobalValue::InternalLinkage,
ConstantInt::get(Type::getInt32Ty(*Ctx),
0xffffffff),
"__llvm_gcov_global_state_pred");
GV->setUnnamedAddr(true);
}
return GV;
}
Function *GCOVProfiler::insertCounterWriteout(
ArrayRef<std::pair<GlobalVariable *, MDNode *> > CountersBySP) {
FunctionType *WriteoutFTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
Function *WriteoutF = M->getFunction("__llvm_gcov_writeout");
if (!WriteoutF)
WriteoutF = Function::Create(WriteoutFTy, GlobalValue::InternalLinkage,
"__llvm_gcov_writeout", M);
WriteoutF->setUnnamedAddr(true);
WriteoutF->addFnAttr(Attribute::NoInline);
if (Options.NoRedZone)
WriteoutF->addFnAttr(Attribute::NoRedZone);
BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", WriteoutF);
IRBuilder<> Builder(BB);
Constant *StartFile = getStartFileFunc();
Constant *EmitFunction = getEmitFunctionFunc();
Constant *EmitArcs = getEmitArcsFunc();
Constant *SummaryInfo = getSummaryInfoFunc();
Constant *EndFile = getEndFileFunc();
NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
if (CU_Nodes) {
for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
auto *CU = cast<DICompileUnit>(CU_Nodes->getOperand(i));
std::string FilenameGcda = mangleName(CU, "gcda");
uint32_t CfgChecksum = FileChecksums.empty() ? 0 : FileChecksums[i];
Builder.CreateCall(StartFile,
{Builder.CreateGlobalStringPtr(FilenameGcda),
Builder.CreateGlobalStringPtr(ReversedVersion),
Builder.getInt32(CfgChecksum)});
for (unsigned j = 0, e = CountersBySP.size(); j != e; ++j) {
auto *SP = cast_or_null<DISubprogram>(CountersBySP[j].second);
uint32_t FuncChecksum = Funcs.empty() ? 0 : Funcs[j]->getFuncChecksum();
Builder.CreateCall(
EmitFunction,
{Builder.getInt32(j),
Options.FunctionNamesInData
? Builder.CreateGlobalStringPtr(getFunctionName(SP))
: Constant::getNullValue(Builder.getInt8PtrTy()),
Builder.getInt32(FuncChecksum),
Builder.getInt8(Options.UseCfgChecksum),
Builder.getInt32(CfgChecksum)});
GlobalVariable *GV = CountersBySP[j].first;
unsigned Arcs =
cast<ArrayType>(GV->getType()->getElementType())->getNumElements();
Builder.CreateCall(EmitArcs, {Builder.getInt32(Arcs),
Builder.CreateConstGEP2_64(GV, 0, 0)});
}
Builder.CreateCall(SummaryInfo, {});
Builder.CreateCall(EndFile, {});
}
}
Builder.CreateRetVoid();
return WriteoutF;
}
void GCOVProfiler::insertIndirectCounterIncrement() {
Function *Fn =
cast<Function>(GCOVProfiler::getIncrementIndirectCounterFunc());
Fn->setUnnamedAddr(true);
Fn->setLinkage(GlobalValue::InternalLinkage);
Fn->addFnAttr(Attribute::NoInline);
if (Options.NoRedZone)
Fn->addFnAttr(Attribute::NoRedZone);
// Create basic blocks for function.
BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", Fn);
IRBuilder<> Builder(BB);
BasicBlock *PredNotNegOne = BasicBlock::Create(*Ctx, "", Fn);
BasicBlock *CounterEnd = BasicBlock::Create(*Ctx, "", Fn);
BasicBlock *Exit = BasicBlock::Create(*Ctx, "exit", Fn);
// uint32_t pred = *predecessor;
// if (pred == 0xffffffff) return;
Argument *Arg = Fn->arg_begin();
Arg->setName("predecessor");
Value *Pred = Builder.CreateLoad(Arg, "pred");
Value *Cond = Builder.CreateICmpEQ(Pred, Builder.getInt32(0xffffffff));
BranchInst::Create(Exit, PredNotNegOne, Cond, BB);
Builder.SetInsertPoint(PredNotNegOne);
// uint64_t *counter = counters[pred];
// if (!counter) return;
Value *ZExtPred = Builder.CreateZExt(Pred, Builder.getInt64Ty());
Arg = std::next(Fn->arg_begin());
Arg->setName("counters");
Value *GEP = Builder.CreateGEP(Type::getInt64PtrTy(*Ctx), Arg, ZExtPred);
Value *Counter = Builder.CreateLoad(GEP, "counter");
Cond = Builder.CreateICmpEQ(Counter,
Constant::getNullValue(
Builder.getInt64Ty()->getPointerTo()));
Builder.CreateCondBr(Cond, Exit, CounterEnd);
// ++*counter;
Builder.SetInsertPoint(CounterEnd);
Value *Add = Builder.CreateAdd(Builder.CreateLoad(Counter),
Builder.getInt64(1));
Builder.CreateStore(Add, Counter);
Builder.CreateBr(Exit);
// Fill in the exit block.
Builder.SetInsertPoint(Exit);
Builder.CreateRetVoid();
}
Function *GCOVProfiler::
insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> > CountersBySP) {
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
Function *FlushF = M->getFunction("__llvm_gcov_flush");
if (!FlushF)
FlushF = Function::Create(FTy, GlobalValue::InternalLinkage,
"__llvm_gcov_flush", M);
else
FlushF->setLinkage(GlobalValue::InternalLinkage);
FlushF->setUnnamedAddr(true);
FlushF->addFnAttr(Attribute::NoInline);
if (Options.NoRedZone)
FlushF->addFnAttr(Attribute::NoRedZone);
BasicBlock *Entry = BasicBlock::Create(*Ctx, "entry", FlushF);
// Write out the current counters.
Constant *WriteoutF = M->getFunction("__llvm_gcov_writeout");
assert(WriteoutF && "Need to create the writeout function first!");
IRBuilder<> Builder(Entry);
Builder.CreateCall(WriteoutF, {});
// Zero out the counters.
for (ArrayRef<std::pair<GlobalVariable *, MDNode *> >::iterator
I = CountersBySP.begin(), E = CountersBySP.end();
I != E; ++I) {
GlobalVariable *GV = I->first;
Constant *Null = Constant::getNullValue(GV->getType()->getElementType());
Builder.CreateStore(Null, GV);
}
Type *RetTy = FlushF->getReturnType();
if (RetTy == Type::getVoidTy(*Ctx))
Builder.CreateRetVoid();
else if (RetTy->isIntegerTy())
// Used if __llvm_gcov_flush was implicitly declared.
Builder.CreateRet(ConstantInt::get(RetTy, 0));
else
report_fatal_error("invalid return type for __llvm_gcov_flush");
return FlushF;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Instrumentation/SanitizerCoverage.cpp | //===-- SanitizerCoverage.cpp - coverage instrumentation for sanitizers ---===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Coverage instrumentation that works with AddressSanitizer
// and potentially with other Sanitizers.
//
// We create a Guard variable with the same linkage
// as the function and inject this code into the entry block (SCK_Function)
// or all blocks (SCK_BB):
// if (Guard < 0) {
// __sanitizer_cov(&Guard);
// }
// The accesses to Guard are atomic. The rest of the logic is
// in __sanitizer_cov (it's fine to call it more than once).
//
// With SCK_Edge we also split critical edges this effectively
// instrumenting all edges.
//
// This coverage implementation provides very limited data:
// it only tells if a given function (block) was ever executed. No counters.
// But for many use cases this is what we need and the added slowdown small.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Instrumentation.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InlineAsm.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Type.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/ModuleUtils.h"
using namespace llvm;
#define DEBUG_TYPE "sancov"
static const char *const kSanCovModuleInitName = "__sanitizer_cov_module_init";
static const char *const kSanCovName = "__sanitizer_cov";
static const char *const kSanCovWithCheckName = "__sanitizer_cov_with_check";
static const char *const kSanCovIndirCallName = "__sanitizer_cov_indir_call16";
static const char *const kSanCovTraceEnter = "__sanitizer_cov_trace_func_enter";
static const char *const kSanCovTraceBB = "__sanitizer_cov_trace_basic_block";
static const char *const kSanCovTraceCmp = "__sanitizer_cov_trace_cmp";
static const char *const kSanCovModuleCtorName = "sancov.module_ctor";
static const uint64_t kSanCtorAndDtorPriority = 2;
static cl::opt<int> ClCoverageLevel("sanitizer-coverage-level",
cl::desc("Sanitizer Coverage. 0: none, 1: entry block, 2: all blocks, "
"3: all blocks and critical edges, "
"4: above plus indirect calls"),
cl::Hidden, cl::init(0));
static cl::opt<unsigned> ClCoverageBlockThreshold(
"sanitizer-coverage-block-threshold",
cl::desc("Use a callback with a guard check inside it if there are"
" more than this number of blocks."),
cl::Hidden, cl::init(500));
static cl::opt<bool>
ClExperimentalTracing("sanitizer-coverage-experimental-tracing",
cl::desc("Experimental basic-block tracing: insert "
"callbacks at every basic block"),
cl::Hidden, cl::init(false));
static cl::opt<bool>
ClExperimentalCMPTracing("sanitizer-coverage-experimental-trace-compares",
cl::desc("Experimental tracing of CMP and similar "
"instructions"),
cl::Hidden, cl::init(false));
// Experimental 8-bit counters used as an additional search heuristic during
// coverage-guided fuzzing.
// The counters are not thread-friendly:
// - contention on these counters may cause significant slowdown;
// - the counter updates are racy and the results may be inaccurate.
// They are also inaccurate due to 8-bit integer overflow.
static cl::opt<bool> ClUse8bitCounters("sanitizer-coverage-8bit-counters",
cl::desc("Experimental 8-bit counters"),
cl::Hidden, cl::init(false));
namespace {
SanitizerCoverageOptions getOptions(int LegacyCoverageLevel) {
SanitizerCoverageOptions Res;
switch (LegacyCoverageLevel) {
case 0:
Res.CoverageType = SanitizerCoverageOptions::SCK_None;
break;
case 1:
Res.CoverageType = SanitizerCoverageOptions::SCK_Function;
break;
case 2:
Res.CoverageType = SanitizerCoverageOptions::SCK_BB;
break;
case 3:
Res.CoverageType = SanitizerCoverageOptions::SCK_Edge;
break;
case 4:
Res.CoverageType = SanitizerCoverageOptions::SCK_Edge;
Res.IndirectCalls = true;
break;
}
return Res;
}
SanitizerCoverageOptions OverrideFromCL(SanitizerCoverageOptions Options) {
// Sets CoverageType and IndirectCalls.
SanitizerCoverageOptions CLOpts = getOptions(ClCoverageLevel);
Options.CoverageType = std::max(Options.CoverageType, CLOpts.CoverageType);
Options.IndirectCalls |= CLOpts.IndirectCalls;
Options.TraceBB |= ClExperimentalTracing;
Options.TraceCmp |= ClExperimentalCMPTracing;
Options.Use8bitCounters |= ClUse8bitCounters;
return Options;
}
class SanitizerCoverageModule : public ModulePass {
public:
SanitizerCoverageModule(
const SanitizerCoverageOptions &Options = SanitizerCoverageOptions())
: ModulePass(ID), Options(OverrideFromCL(Options)) {}
bool runOnModule(Module &M) override;
bool runOnFunction(Function &F);
static char ID; // Pass identification, replacement for typeid
StringRef getPassName() const override {
return "SanitizerCoverageModule";
}
private:
void InjectCoverageForIndirectCalls(Function &F,
ArrayRef<Instruction *> IndirCalls);
void InjectTraceForCmp(Function &F, ArrayRef<Instruction *> CmpTraceTargets);
bool InjectCoverage(Function &F, ArrayRef<BasicBlock *> AllBlocks);
void SetNoSanitizeMetadata(Instruction *I);
void InjectCoverageAtBlock(Function &F, BasicBlock &BB, bool UseCalls);
unsigned NumberOfInstrumentedBlocks() {
return SanCovFunction->getNumUses() + SanCovWithCheckFunction->getNumUses();
}
Function *SanCovFunction;
Function *SanCovWithCheckFunction;
Function *SanCovIndirCallFunction;
Function *SanCovTraceEnter, *SanCovTraceBB;
Function *SanCovTraceCmpFunction;
InlineAsm *EmptyAsm;
Type *IntptrTy, *Int64Ty;
LLVMContext *C;
const DataLayout *DL;
GlobalVariable *GuardArray;
GlobalVariable *EightBitCounterArray;
SanitizerCoverageOptions Options;
};
} // namespace
bool SanitizerCoverageModule::runOnModule(Module &M) {
if (Options.CoverageType == SanitizerCoverageOptions::SCK_None)
return false;
C = &(M.getContext());
DL = &M.getDataLayout();
IntptrTy = Type::getIntNTy(*C, DL->getPointerSizeInBits());
Type *VoidTy = Type::getVoidTy(*C);
IRBuilder<> IRB(*C);
Type *Int8PtrTy = PointerType::getUnqual(IRB.getInt8Ty());
Type *Int32PtrTy = PointerType::getUnqual(IRB.getInt32Ty());
Int64Ty = IRB.getInt64Ty();
SanCovFunction = checkSanitizerInterfaceFunction(
M.getOrInsertFunction(kSanCovName, VoidTy, Int32PtrTy, nullptr));
SanCovWithCheckFunction = checkSanitizerInterfaceFunction(
M.getOrInsertFunction(kSanCovWithCheckName, VoidTy, Int32PtrTy, nullptr));
SanCovIndirCallFunction =
checkSanitizerInterfaceFunction(M.getOrInsertFunction(
kSanCovIndirCallName, VoidTy, IntptrTy, IntptrTy, nullptr));
SanCovTraceCmpFunction =
checkSanitizerInterfaceFunction(M.getOrInsertFunction(
kSanCovTraceCmp, VoidTy, Int64Ty, Int64Ty, Int64Ty, nullptr));
// We insert an empty inline asm after cov callbacks to avoid callback merge.
EmptyAsm = InlineAsm::get(FunctionType::get(IRB.getVoidTy(), false),
StringRef(""), StringRef(""),
/*hasSideEffects=*/true);
if (Options.TraceBB) {
SanCovTraceEnter = checkSanitizerInterfaceFunction(
M.getOrInsertFunction(kSanCovTraceEnter, VoidTy, Int32PtrTy, nullptr));
SanCovTraceBB = checkSanitizerInterfaceFunction(
M.getOrInsertFunction(kSanCovTraceBB, VoidTy, Int32PtrTy, nullptr));
}
// At this point we create a dummy array of guards because we don't
// know how many elements we will need.
Type *Int32Ty = IRB.getInt32Ty();
Type *Int8Ty = IRB.getInt8Ty();
GuardArray =
new GlobalVariable(M, Int32Ty, false, GlobalValue::ExternalLinkage,
nullptr, "__sancov_gen_cov_tmp");
if (Options.Use8bitCounters)
EightBitCounterArray =
new GlobalVariable(M, Int8Ty, false, GlobalVariable::ExternalLinkage,
nullptr, "__sancov_gen_cov_tmp");
for (auto &F : M)
runOnFunction(F);
auto N = NumberOfInstrumentedBlocks();
// Now we know how many elements we need. Create an array of guards
// with one extra element at the beginning for the size.
Type *Int32ArrayNTy = ArrayType::get(Int32Ty, N + 1);
GlobalVariable *RealGuardArray = new GlobalVariable(
M, Int32ArrayNTy, false, GlobalValue::PrivateLinkage,
Constant::getNullValue(Int32ArrayNTy), "__sancov_gen_cov");
// Replace the dummy array with the real one.
GuardArray->replaceAllUsesWith(
IRB.CreatePointerCast(RealGuardArray, Int32PtrTy));
GuardArray->eraseFromParent();
GlobalVariable *RealEightBitCounterArray;
if (Options.Use8bitCounters) {
// Make sure the array is 16-aligned.
static const int kCounterAlignment = 16;
Type *Int8ArrayNTy =
ArrayType::get(Int8Ty, RoundUpToAlignment(N, kCounterAlignment));
RealEightBitCounterArray = new GlobalVariable(
M, Int8ArrayNTy, false, GlobalValue::PrivateLinkage,
Constant::getNullValue(Int8ArrayNTy), "__sancov_gen_cov_counter");
RealEightBitCounterArray->setAlignment(kCounterAlignment);
EightBitCounterArray->replaceAllUsesWith(
IRB.CreatePointerCast(RealEightBitCounterArray, Int8PtrTy));
EightBitCounterArray->eraseFromParent();
}
// Create variable for module (compilation unit) name
Constant *ModNameStrConst =
ConstantDataArray::getString(M.getContext(), M.getName(), true);
GlobalVariable *ModuleName =
new GlobalVariable(M, ModNameStrConst->getType(), true,
GlobalValue::PrivateLinkage, ModNameStrConst);
Function *CtorFunc;
std::tie(CtorFunc, std::ignore) = createSanitizerCtorAndInitFunctions(
M, kSanCovModuleCtorName, kSanCovModuleInitName,
{Int32PtrTy, IntptrTy, Int8PtrTy, Int8PtrTy},
{IRB.CreatePointerCast(RealGuardArray, Int32PtrTy),
ConstantInt::get(IntptrTy, N),
Options.Use8bitCounters
? IRB.CreatePointerCast(RealEightBitCounterArray, Int8PtrTy)
: Constant::getNullValue(Int8PtrTy),
IRB.CreatePointerCast(ModuleName, Int8PtrTy)});
appendToGlobalCtors(M, CtorFunc, kSanCtorAndDtorPriority);
return true;
}
bool SanitizerCoverageModule::runOnFunction(Function &F) {
if (F.empty()) return false;
if (F.getName().find(".module_ctor") != std::string::npos)
return false; // Should not instrument sanitizer init functions.
if (Options.CoverageType >= SanitizerCoverageOptions::SCK_Edge)
SplitAllCriticalEdges(F);
SmallVector<Instruction*, 8> IndirCalls;
SmallVector<BasicBlock*, 16> AllBlocks;
SmallVector<Instruction*, 8> CmpTraceTargets;
for (auto &BB : F) {
AllBlocks.push_back(&BB);
for (auto &Inst : BB) {
if (Options.IndirectCalls) {
CallSite CS(&Inst);
if (CS && !CS.getCalledFunction())
IndirCalls.push_back(&Inst);
}
if (Options.TraceCmp && isa<ICmpInst>(&Inst))
CmpTraceTargets.push_back(&Inst);
}
}
InjectCoverage(F, AllBlocks);
InjectCoverageForIndirectCalls(F, IndirCalls);
InjectTraceForCmp(F, CmpTraceTargets);
return true;
}
bool SanitizerCoverageModule::InjectCoverage(Function &F,
ArrayRef<BasicBlock *> AllBlocks) {
switch (Options.CoverageType) {
case SanitizerCoverageOptions::SCK_None:
return false;
case SanitizerCoverageOptions::SCK_Function:
InjectCoverageAtBlock(F, F.getEntryBlock(), false);
return true;
default: {
bool UseCalls = ClCoverageBlockThreshold < AllBlocks.size();
for (auto BB : AllBlocks)
InjectCoverageAtBlock(F, *BB, UseCalls);
return true;
}
}
}
// On every indirect call we call a run-time function
// __sanitizer_cov_indir_call* with two parameters:
// - callee address,
// - global cache array that contains kCacheSize pointers (zero-initialized).
// The cache is used to speed up recording the caller-callee pairs.
// The address of the caller is passed implicitly via caller PC.
// kCacheSize is encoded in the name of the run-time function.
void SanitizerCoverageModule::InjectCoverageForIndirectCalls(
Function &F, ArrayRef<Instruction *> IndirCalls) {
if (IndirCalls.empty()) return;
const int kCacheSize = 16;
const int kCacheAlignment = 64; // Align for better performance.
Type *Ty = ArrayType::get(IntptrTy, kCacheSize);
for (auto I : IndirCalls) {
IRBuilder<> IRB(I);
CallSite CS(I);
Value *Callee = CS.getCalledValue();
if (isa<InlineAsm>(Callee)) continue;
GlobalVariable *CalleeCache = new GlobalVariable(
*F.getParent(), Ty, false, GlobalValue::PrivateLinkage,
Constant::getNullValue(Ty), "__sancov_gen_callee_cache");
CalleeCache->setAlignment(kCacheAlignment);
IRB.CreateCall(SanCovIndirCallFunction,
{IRB.CreatePointerCast(Callee, IntptrTy),
IRB.CreatePointerCast(CalleeCache, IntptrTy)});
}
}
void SanitizerCoverageModule::InjectTraceForCmp(
Function &F, ArrayRef<Instruction *> CmpTraceTargets) {
for (auto I : CmpTraceTargets) {
if (ICmpInst *ICMP = dyn_cast<ICmpInst>(I)) {
IRBuilder<> IRB(ICMP);
Value *A0 = ICMP->getOperand(0);
Value *A1 = ICMP->getOperand(1);
if (!A0->getType()->isIntegerTy()) continue;
uint64_t TypeSize = DL->getTypeStoreSizeInBits(A0->getType());
// __sanitizer_cov_trace_cmp((type_size << 32) | predicate, A0, A1);
IRB.CreateCall(
SanCovTraceCmpFunction,
{ConstantInt::get(Int64Ty, (TypeSize << 32) | ICMP->getPredicate()),
IRB.CreateIntCast(A0, Int64Ty, true),
IRB.CreateIntCast(A1, Int64Ty, true)});
}
}
}
void SanitizerCoverageModule::SetNoSanitizeMetadata(Instruction *I) {
I->setMetadata(
I->getParent()->getParent()->getParent()->getMDKindID("nosanitize"),
MDNode::get(*C, None));
}
void SanitizerCoverageModule::InjectCoverageAtBlock(Function &F, BasicBlock &BB,
bool UseCalls) {
// Don't insert coverage for unreachable blocks: we will never call
// __sanitizer_cov() for them, so counting them in
// NumberOfInstrumentedBlocks() might complicate calculation of code coverage
// percentage. Also, unreachable instructions frequently have no debug
// locations.
if (isa<UnreachableInst>(BB.getTerminator()))
return;
BasicBlock::iterator IP = BB.getFirstInsertionPt(), BE = BB.end();
// Skip static allocas at the top of the entry block so they don't become
// dynamic when we split the block. If we used our optimized stack layout,
// then there will only be one alloca and it will come first.
for (; IP != BE; ++IP) {
AllocaInst *AI = dyn_cast<AllocaInst>(IP);
if (!AI || !AI->isStaticAlloca())
break;
}
bool IsEntryBB = &BB == &F.getEntryBlock();
DebugLoc EntryLoc;
if (IsEntryBB) {
if (auto SP = getDISubprogram(&F))
EntryLoc = DebugLoc::get(SP->getScopeLine(), 0, SP);
} else {
EntryLoc = IP->getDebugLoc();
}
IRBuilder<> IRB(IP);
IRB.SetCurrentDebugLocation(EntryLoc);
SmallVector<Value *, 1> Indices;
Value *GuardP = IRB.CreateAdd(
IRB.CreatePointerCast(GuardArray, IntptrTy),
ConstantInt::get(IntptrTy, (1 + NumberOfInstrumentedBlocks()) * 4));
Type *Int32PtrTy = PointerType::getUnqual(IRB.getInt32Ty());
GuardP = IRB.CreateIntToPtr(GuardP, Int32PtrTy);
if (UseCalls) {
IRB.CreateCall(SanCovWithCheckFunction, GuardP);
} else {
LoadInst *Load = IRB.CreateLoad(GuardP);
Load->setAtomic(Monotonic);
Load->setAlignment(4);
SetNoSanitizeMetadata(Load);
Value *Cmp = IRB.CreateICmpSGE(Constant::getNullValue(Load->getType()), Load);
Instruction *Ins = SplitBlockAndInsertIfThen(
Cmp, IP, false, MDBuilder(*C).createBranchWeights(1, 100000));
IRB.SetInsertPoint(Ins);
IRB.SetCurrentDebugLocation(EntryLoc);
// __sanitizer_cov gets the PC of the instruction using GET_CALLER_PC.
IRB.CreateCall(SanCovFunction, GuardP);
IRB.CreateCall(EmptyAsm, {}); // Avoids callback merge.
}
if (Options.Use8bitCounters) {
IRB.SetInsertPoint(IP);
Value *P = IRB.CreateAdd(
IRB.CreatePointerCast(EightBitCounterArray, IntptrTy),
ConstantInt::get(IntptrTy, NumberOfInstrumentedBlocks() - 1));
P = IRB.CreateIntToPtr(P, IRB.getInt8PtrTy());
LoadInst *LI = IRB.CreateLoad(P);
Value *Inc = IRB.CreateAdd(LI, ConstantInt::get(IRB.getInt8Ty(), 1));
StoreInst *SI = IRB.CreateStore(Inc, P);
SetNoSanitizeMetadata(LI);
SetNoSanitizeMetadata(SI);
}
if (Options.TraceBB) {
// Experimental support for tracing.
// Insert a callback with the same guard variable as used for coverage.
IRB.SetInsertPoint(IP);
IRB.CreateCall(IsEntryBB ? SanCovTraceEnter : SanCovTraceBB, GuardP);
}
}
char SanitizerCoverageModule::ID = 0;
INITIALIZE_PASS(SanitizerCoverageModule, "sancov",
"SanitizerCoverage: TODO."
"ModulePass", false, false)
ModulePass *llvm::createSanitizerCoverageModulePass(
const SanitizerCoverageOptions &Options) {
return new SanitizerCoverageModule(Options);
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Hello/Hello.cpp | //===- Hello.cpp - Example code from "Writing an LLVM Pass" ---------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements two versions of the LLVM "Hello World" pass described
// in docs/WritingAnLLVMPass.html
//
//===----------------------------------------------------------------------===//
#include "llvm/ADT/Statistic.h"
#include "llvm/IR/Function.h"
#include "llvm/Pass.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
#define DEBUG_TYPE "hello"
STATISTIC(HelloCounter, "Counts number of functions greeted");
namespace {
// Hello - The first implementation, without getAnalysisUsage.
struct Hello : public FunctionPass {
static char ID; // Pass identification, replacement for typeid
Hello() : FunctionPass(ID) {}
bool runOnFunction(Function &F) override {
++HelloCounter;
errs() << "Hello: ";
errs().write_escaped(F.getName()) << '\n';
return false;
}
};
}
char Hello::ID = 0;
static RegisterPass<Hello> X("hello", "Hello World Pass");
namespace {
// Hello2 - The second implementation with getAnalysisUsage implemented.
struct Hello2 : public FunctionPass {
static char ID; // Pass identification, replacement for typeid
Hello2() : FunctionPass(ID) {}
bool runOnFunction(Function &F) override {
++HelloCounter;
errs() << "Hello: ";
errs().write_escaped(F.getName()) << '\n';
return false;
}
// We don't modify the program, so we preserve all analyses.
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.setPreservesAll();
}
};
}
char Hello2::ID = 0;
static RegisterPass<Hello2>
Y("hello2", "Hello World Pass (with getAnalysisUsage implemented)");
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Hello/CMakeLists.txt | # If we don't need RTTI or EH, there's no reason to export anything
# from the hello plugin.
if( NOT LLVM_REQUIRES_RTTI )
if( NOT LLVM_REQUIRES_EH )
set(LLVM_EXPORTED_SYMBOL_FILE ${CMAKE_CURRENT_SOURCE_DIR}/Hello.exports)
endif()
endif()
if(WIN32 OR CYGWIN)
set(LLVM_LINK_COMPONENTS Core Support)
endif()
add_llvm_loadable_module( LLVMHello
Hello.cpp
DEPENDS
intrinsics_gen
)
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/InstCombineCasts.cpp | //===- InstCombineCasts.cpp -----------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the visit functions for cast operations.
//
//===----------------------------------------------------------------------===//
#include "InstCombineInternal.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
using namespace llvm;
using namespace PatternMatch;
#define DEBUG_TYPE "instcombine"
/// DecomposeSimpleLinearExpr - Analyze 'Val', seeing if it is a simple linear
/// expression. If so, decompose it, returning some value X, such that Val is
/// X*Scale+Offset.
///
static Value *DecomposeSimpleLinearExpr(Value *Val, unsigned &Scale,
uint64_t &Offset) {
if (ConstantInt *CI = dyn_cast<ConstantInt>(Val)) {
Offset = CI->getZExtValue();
Scale = 0;
return ConstantInt::get(Val->getType(), 0);
}
if (BinaryOperator *I = dyn_cast<BinaryOperator>(Val)) {
// Cannot look past anything that might overflow.
OverflowingBinaryOperator *OBI = dyn_cast<OverflowingBinaryOperator>(Val);
if (OBI && !OBI->hasNoUnsignedWrap() && !OBI->hasNoSignedWrap()) {
Scale = 1;
Offset = 0;
return Val;
}
if (ConstantInt *RHS = dyn_cast<ConstantInt>(I->getOperand(1))) {
if (I->getOpcode() == Instruction::Shl) {
// This is a value scaled by '1 << the shift amt'.
Scale = UINT64_C(1) << RHS->getZExtValue();
Offset = 0;
return I->getOperand(0);
}
if (I->getOpcode() == Instruction::Mul) {
// This value is scaled by 'RHS'.
Scale = RHS->getZExtValue();
Offset = 0;
return I->getOperand(0);
}
if (I->getOpcode() == Instruction::Add) {
// We have X+C. Check to see if we really have (X*C2)+C1,
// where C1 is divisible by C2.
unsigned SubScale;
Value *SubVal =
DecomposeSimpleLinearExpr(I->getOperand(0), SubScale, Offset);
Offset += RHS->getZExtValue();
Scale = SubScale;
return SubVal;
}
}
}
// Otherwise, we can't look past this.
Scale = 1;
Offset = 0;
return Val;
}
/// PromoteCastOfAllocation - If we find a cast of an allocation instruction,
/// try to eliminate the cast by moving the type information into the alloc.
Instruction *InstCombiner::PromoteCastOfAllocation(BitCastInst &CI,
AllocaInst &AI) {
PointerType *PTy = cast<PointerType>(CI.getType());
BuilderTy AllocaBuilder(*Builder);
AllocaBuilder.SetInsertPoint(AI.getParent(), &AI);
// Get the type really allocated and the type casted to.
Type *AllocElTy = AI.getAllocatedType();
Type *CastElTy = PTy->getElementType();
if (!AllocElTy->isSized() || !CastElTy->isSized()) return nullptr;
unsigned AllocElTyAlign = DL.getABITypeAlignment(AllocElTy);
unsigned CastElTyAlign = DL.getABITypeAlignment(CastElTy);
if (CastElTyAlign < AllocElTyAlign) return nullptr;
// If the allocation has multiple uses, only promote it if we are strictly
// increasing the alignment of the resultant allocation. If we keep it the
// same, we open the door to infinite loops of various kinds.
if (!AI.hasOneUse() && CastElTyAlign == AllocElTyAlign) return nullptr;
uint64_t AllocElTySize = DL.getTypeAllocSize(AllocElTy);
uint64_t CastElTySize = DL.getTypeAllocSize(CastElTy);
if (CastElTySize == 0 || AllocElTySize == 0) return nullptr;
// If the allocation has multiple uses, only promote it if we're not
// shrinking the amount of memory being allocated.
uint64_t AllocElTyStoreSize = DL.getTypeStoreSize(AllocElTy);
uint64_t CastElTyStoreSize = DL.getTypeStoreSize(CastElTy);
if (!AI.hasOneUse() && CastElTyStoreSize < AllocElTyStoreSize) return nullptr;
// See if we can satisfy the modulus by pulling a scale out of the array
// size argument.
unsigned ArraySizeScale;
uint64_t ArrayOffset;
Value *NumElements = // See if the array size is a decomposable linear expr.
DecomposeSimpleLinearExpr(AI.getOperand(0), ArraySizeScale, ArrayOffset);
// If we can now satisfy the modulus, by using a non-1 scale, we really can
// do the xform.
if ((AllocElTySize*ArraySizeScale) % CastElTySize != 0 ||
(AllocElTySize*ArrayOffset ) % CastElTySize != 0) return nullptr;
unsigned Scale = (AllocElTySize*ArraySizeScale)/CastElTySize;
Value *Amt = nullptr;
if (Scale == 1) {
Amt = NumElements;
} else {
Amt = ConstantInt::get(AI.getArraySize()->getType(), Scale);
// Insert before the alloca, not before the cast.
Amt = AllocaBuilder.CreateMul(Amt, NumElements);
}
if (uint64_t Offset = (AllocElTySize*ArrayOffset)/CastElTySize) {
Value *Off = ConstantInt::get(AI.getArraySize()->getType(),
Offset, true);
Amt = AllocaBuilder.CreateAdd(Amt, Off);
}
AllocaInst *New = AllocaBuilder.CreateAlloca(CastElTy, Amt);
New->setAlignment(AI.getAlignment());
New->takeName(&AI);
New->setUsedWithInAlloca(AI.isUsedWithInAlloca());
// If the allocation has multiple real uses, insert a cast and change all
// things that used it to use the new cast. This will also hack on CI, but it
// will die soon.
if (!AI.hasOneUse()) {
// New is the allocation instruction, pointer typed. AI is the original
// allocation instruction, also pointer typed. Thus, cast to use is BitCast.
Value *NewCast = AllocaBuilder.CreateBitCast(New, AI.getType(), "tmpcast");
ReplaceInstUsesWith(AI, NewCast);
}
return ReplaceInstUsesWith(CI, New);
}
/// EvaluateInDifferentType - Given an expression that
/// CanEvaluateTruncated or CanEvaluateSExtd returns true for, actually
/// insert the code to evaluate the expression.
Value *InstCombiner::EvaluateInDifferentType(Value *V, Type *Ty,
bool isSigned) {
if (Constant *C = dyn_cast<Constant>(V)) {
C = ConstantExpr::getIntegerCast(C, Ty, isSigned /*Sext or ZExt*/);
// If we got a constantexpr back, try to simplify it with DL info.
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C))
C = ConstantFoldConstantExpression(CE, DL, TLI);
return C;
}
// Otherwise, it must be an instruction.
Instruction *I = cast<Instruction>(V);
Instruction *Res = nullptr;
unsigned Opc = I->getOpcode();
switch (Opc) {
case Instruction::Add:
case Instruction::Sub:
case Instruction::Mul:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor:
case Instruction::AShr:
case Instruction::LShr:
case Instruction::Shl:
case Instruction::UDiv:
case Instruction::URem: {
Value *LHS = EvaluateInDifferentType(I->getOperand(0), Ty, isSigned);
Value *RHS = EvaluateInDifferentType(I->getOperand(1), Ty, isSigned);
Res = BinaryOperator::Create((Instruction::BinaryOps)Opc, LHS, RHS);
break;
}
case Instruction::Trunc:
case Instruction::ZExt:
case Instruction::SExt:
// If the source type of the cast is the type we're trying for then we can
// just return the source. There's no need to insert it because it is not
// new.
if (I->getOperand(0)->getType() == Ty)
return I->getOperand(0);
// Otherwise, must be the same type of cast, so just reinsert a new one.
// This also handles the case of zext(trunc(x)) -> zext(x).
Res = CastInst::CreateIntegerCast(I->getOperand(0), Ty,
Opc == Instruction::SExt);
break;
case Instruction::Select: {
Value *True = EvaluateInDifferentType(I->getOperand(1), Ty, isSigned);
Value *False = EvaluateInDifferentType(I->getOperand(2), Ty, isSigned);
Res = SelectInst::Create(I->getOperand(0), True, False);
break;
}
case Instruction::PHI: {
PHINode *OPN = cast<PHINode>(I);
PHINode *NPN = PHINode::Create(Ty, OPN->getNumIncomingValues());
for (unsigned i = 0, e = OPN->getNumIncomingValues(); i != e; ++i) {
Value *V =
EvaluateInDifferentType(OPN->getIncomingValue(i), Ty, isSigned);
NPN->addIncoming(V, OPN->getIncomingBlock(i));
}
Res = NPN;
break;
}
default:
// TODO: Can handle more cases here.
llvm_unreachable("Unreachable!");
}
Res->takeName(I);
return InsertNewInstWith(Res, *I);
}
/// This function is a wrapper around CastInst::isEliminableCastPair. It
/// simply extracts arguments and returns what that function returns.
static Instruction::CastOps
isEliminableCastPair(const CastInst *CI, ///< First cast instruction
unsigned opcode, ///< Opcode for the second cast
Type *DstTy, ///< Target type for the second cast
const DataLayout &DL) {
Type *SrcTy = CI->getOperand(0)->getType(); // A from above
Type *MidTy = CI->getType(); // B from above
// Get the opcodes of the two Cast instructions
Instruction::CastOps firstOp = Instruction::CastOps(CI->getOpcode());
Instruction::CastOps secondOp = Instruction::CastOps(opcode);
Type *SrcIntPtrTy =
SrcTy->isPtrOrPtrVectorTy() ? DL.getIntPtrType(SrcTy) : nullptr;
Type *MidIntPtrTy =
MidTy->isPtrOrPtrVectorTy() ? DL.getIntPtrType(MidTy) : nullptr;
Type *DstIntPtrTy =
DstTy->isPtrOrPtrVectorTy() ? DL.getIntPtrType(DstTy) : nullptr;
unsigned Res = CastInst::isEliminableCastPair(firstOp, secondOp, SrcTy, MidTy,
DstTy, SrcIntPtrTy, MidIntPtrTy,
DstIntPtrTy);
// We don't want to form an inttoptr or ptrtoint that converts to an integer
// type that differs from the pointer size.
if ((Res == Instruction::IntToPtr && SrcTy != DstIntPtrTy) ||
(Res == Instruction::PtrToInt && DstTy != SrcIntPtrTy))
Res = 0;
return Instruction::CastOps(Res);
}
/// ShouldOptimizeCast - Return true if the cast from "V to Ty" actually
/// results in any code being generated and is interesting to optimize out. If
/// the cast can be eliminated by some other simple transformation, we prefer
/// to do the simplification first.
bool InstCombiner::ShouldOptimizeCast(Instruction::CastOps opc, const Value *V,
Type *Ty) {
// Noop casts and casts of constants should be eliminated trivially.
if (V->getType() == Ty || isa<Constant>(V)) return false;
// If this is another cast that can be eliminated, we prefer to have it
// eliminated.
if (const CastInst *CI = dyn_cast<CastInst>(V))
if (isEliminableCastPair(CI, opc, Ty, DL))
return false;
// If this is a vector sext from a compare, then we don't want to break the
// idiom where each element of the extended vector is either zero or all ones.
if (opc == Instruction::SExt && isa<CmpInst>(V) && Ty->isVectorTy())
return false;
return true;
}
/// @brief Implement the transforms common to all CastInst visitors.
Instruction *InstCombiner::commonCastTransforms(CastInst &CI) {
Value *Src = CI.getOperand(0);
// Many cases of "cast of a cast" are eliminable. If it's eliminable we just
// eliminate it now.
if (CastInst *CSrc = dyn_cast<CastInst>(Src)) { // A->B->C cast
if (Instruction::CastOps opc =
isEliminableCastPair(CSrc, CI.getOpcode(), CI.getType(), DL)) {
// The first cast (CSrc) is eliminable so we need to fix up or replace
// the second cast (CI). CSrc will then have a good chance of being dead.
return CastInst::Create(opc, CSrc->getOperand(0), CI.getType());
}
}
// If we are casting a select then fold the cast into the select
if (SelectInst *SI = dyn_cast<SelectInst>(Src))
if (Instruction *NV = FoldOpIntoSelect(CI, SI))
return NV;
// If we are casting a PHI then fold the cast into the PHI
if (isa<PHINode>(Src)) {
// We don't do this if this would create a PHI node with an illegal type if
// it is currently legal.
if (!Src->getType()->isIntegerTy() || !CI.getType()->isIntegerTy() ||
ShouldChangeType(CI.getType(), Src->getType()))
if (Instruction *NV = FoldOpIntoPhi(CI))
return NV;
}
return nullptr;
}
/// CanEvaluateTruncated - Return true if we can evaluate the specified
/// expression tree as type Ty instead of its larger type, and arrive with the
/// same value. This is used by code that tries to eliminate truncates.
///
/// Ty will always be a type smaller than V. We should return true if trunc(V)
/// can be computed by computing V in the smaller type. If V is an instruction,
/// then trunc(inst(x,y)) can be computed as inst(trunc(x),trunc(y)), which only
/// makes sense if x and y can be efficiently truncated.
///
/// This function works on both vectors and scalars.
///
static bool CanEvaluateTruncated(Value *V, Type *Ty, InstCombiner &IC,
Instruction *CxtI) {
// We can always evaluate constants in another type.
if (isa<Constant>(V))
return true;
Instruction *I = dyn_cast<Instruction>(V);
if (!I) return false;
Type *OrigTy = V->getType();
// If this is an extension from the dest type, we can eliminate it, even if it
// has multiple uses.
if ((isa<ZExtInst>(I) || isa<SExtInst>(I)) &&
I->getOperand(0)->getType() == Ty)
return true;
// We can't extend or shrink something that has multiple uses: doing so would
// require duplicating the instruction in general, which isn't profitable.
if (!I->hasOneUse()) return false;
unsigned Opc = I->getOpcode();
switch (Opc) {
case Instruction::Add:
case Instruction::Sub:
case Instruction::Mul:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor:
// These operators can all arbitrarily be extended or truncated.
return CanEvaluateTruncated(I->getOperand(0), Ty, IC, CxtI) &&
CanEvaluateTruncated(I->getOperand(1), Ty, IC, CxtI);
case Instruction::UDiv:
case Instruction::URem: {
// UDiv and URem can be truncated if all the truncated bits are zero.
uint32_t OrigBitWidth = OrigTy->getScalarSizeInBits();
uint32_t BitWidth = Ty->getScalarSizeInBits();
if (BitWidth < OrigBitWidth) {
APInt Mask = APInt::getHighBitsSet(OrigBitWidth, OrigBitWidth-BitWidth);
if (IC.MaskedValueIsZero(I->getOperand(0), Mask, 0, CxtI) &&
IC.MaskedValueIsZero(I->getOperand(1), Mask, 0, CxtI)) {
return CanEvaluateTruncated(I->getOperand(0), Ty, IC, CxtI) &&
CanEvaluateTruncated(I->getOperand(1), Ty, IC, CxtI);
}
}
break;
}
case Instruction::Shl:
// If we are truncating the result of this SHL, and if it's a shift of a
// constant amount, we can always perform a SHL in a smaller type.
if (ConstantInt *CI = dyn_cast<ConstantInt>(I->getOperand(1))) {
uint32_t BitWidth = Ty->getScalarSizeInBits();
if (CI->getLimitedValue(BitWidth) < BitWidth)
return CanEvaluateTruncated(I->getOperand(0), Ty, IC, CxtI);
}
break;
case Instruction::LShr:
// If this is a truncate of a logical shr, we can truncate it to a smaller
// lshr iff we know that the bits we would otherwise be shifting in are
// already zeros.
if (ConstantInt *CI = dyn_cast<ConstantInt>(I->getOperand(1))) {
uint32_t OrigBitWidth = OrigTy->getScalarSizeInBits();
uint32_t BitWidth = Ty->getScalarSizeInBits();
if (IC.MaskedValueIsZero(I->getOperand(0),
APInt::getHighBitsSet(OrigBitWidth, OrigBitWidth-BitWidth), 0, CxtI) &&
CI->getLimitedValue(BitWidth) < BitWidth) {
return CanEvaluateTruncated(I->getOperand(0), Ty, IC, CxtI);
}
}
break;
case Instruction::Trunc:
// trunc(trunc(x)) -> trunc(x)
return true;
case Instruction::ZExt:
case Instruction::SExt:
// trunc(ext(x)) -> ext(x) if the source type is smaller than the new dest
// trunc(ext(x)) -> trunc(x) if the source type is larger than the new dest
return true;
case Instruction::Select: {
SelectInst *SI = cast<SelectInst>(I);
return CanEvaluateTruncated(SI->getTrueValue(), Ty, IC, CxtI) &&
CanEvaluateTruncated(SI->getFalseValue(), Ty, IC, CxtI);
}
case Instruction::PHI: {
// We can change a phi if we can change all operands. Note that we never
// get into trouble with cyclic PHIs here because we only consider
// instructions with a single use.
PHINode *PN = cast<PHINode>(I);
for (Value *IncValue : PN->incoming_values())
if (!CanEvaluateTruncated(IncValue, Ty, IC, CxtI))
return false;
return true;
}
default:
// TODO: Can handle more cases here.
break;
}
return false;
}
Instruction *InstCombiner::visitTrunc(TruncInst &CI) {
if (Instruction *Result = commonCastTransforms(CI))
return Result;
// Test if the trunc is the user of a select which is part of a
// minimum or maximum operation. If so, don't do any more simplification.
// Even simplifying demanded bits can break the canonical form of a
// min/max.
Value *LHS, *RHS;
if (SelectInst *SI = dyn_cast<SelectInst>(CI.getOperand(0)))
if (matchSelectPattern(SI, LHS, RHS) != SPF_UNKNOWN)
return nullptr;
// See if we can simplify any instructions used by the input whose sole
// purpose is to compute bits we don't care about.
if (SimplifyDemandedInstructionBits(CI))
return &CI;
Value *Src = CI.getOperand(0);
Type *DestTy = CI.getType(), *SrcTy = Src->getType();
// Attempt to truncate the entire input expression tree to the destination
// type. Only do this if the dest type is a simple type, don't convert the
// expression tree to something weird like i93 unless the source is also
// strange.
if ((DestTy->isVectorTy() || ShouldChangeType(SrcTy, DestTy)) &&
CanEvaluateTruncated(Src, DestTy, *this, &CI)) {
// If this cast is a truncate, evaluting in a different type always
// eliminates the cast, so it is always a win.
DEBUG(dbgs() << "ICE: EvaluateInDifferentType converting expression type"
" to avoid cast: " << CI << '\n');
Value *Res = EvaluateInDifferentType(Src, DestTy, false);
assert(Res->getType() == DestTy);
return ReplaceInstUsesWith(CI, Res);
}
// Canonicalize trunc x to i1 -> (icmp ne (and x, 1), 0), likewise for vector.
if (DestTy->getScalarSizeInBits() == 1) {
Constant *One = ConstantInt::get(Src->getType(), 1);
Src = Builder->CreateAnd(Src, One);
Value *Zero = Constant::getNullValue(Src->getType());
return new ICmpInst(ICmpInst::ICMP_NE, Src, Zero);
}
// Transform trunc(lshr (zext A), Cst) to eliminate one type conversion.
Value *A = nullptr; ConstantInt *Cst = nullptr;
if (Src->hasOneUse() &&
match(Src, m_LShr(m_ZExt(m_Value(A)), m_ConstantInt(Cst)))) {
// We have three types to worry about here, the type of A, the source of
// the truncate (MidSize), and the destination of the truncate. We know that
// ASize < MidSize and MidSize > ResultSize, but don't know the relation
// between ASize and ResultSize.
unsigned ASize = A->getType()->getPrimitiveSizeInBits();
// If the shift amount is larger than the size of A, then the result is
// known to be zero because all the input bits got shifted out.
if (Cst->getZExtValue() >= ASize)
return ReplaceInstUsesWith(CI, Constant::getNullValue(CI.getType()));
// Since we're doing an lshr and a zero extend, and know that the shift
// amount is smaller than ASize, it is always safe to do the shift in A's
// type, then zero extend or truncate to the result.
Value *Shift = Builder->CreateLShr(A, Cst->getZExtValue());
Shift->takeName(Src);
return CastInst::CreateIntegerCast(Shift, CI.getType(), false);
}
// Transform "trunc (and X, cst)" -> "and (trunc X), cst" so long as the dest
// type isn't non-native.
if (Src->hasOneUse() && isa<IntegerType>(Src->getType()) &&
ShouldChangeType(Src->getType(), CI.getType()) &&
match(Src, m_And(m_Value(A), m_ConstantInt(Cst)))) {
Value *NewTrunc = Builder->CreateTrunc(A, CI.getType(), A->getName()+".tr");
return BinaryOperator::CreateAnd(NewTrunc,
ConstantExpr::getTrunc(Cst, CI.getType()));
}
return nullptr;
}
/// transformZExtICmp - Transform (zext icmp) to bitwise / integer operations
/// in order to eliminate the icmp.
Instruction *InstCombiner::transformZExtICmp(ICmpInst *ICI, Instruction &CI,
bool DoXform) {
// If we are just checking for a icmp eq of a single bit and zext'ing it
// to an integer, then shift the bit to the appropriate place and then
// cast to integer to avoid the comparison.
if (ConstantInt *Op1C = dyn_cast<ConstantInt>(ICI->getOperand(1))) {
const APInt &Op1CV = Op1C->getValue();
// zext (x <s 0) to i32 --> x>>u31 true if signbit set.
// zext (x >s -1) to i32 --> (x>>u31)^1 true if signbit clear.
if ((ICI->getPredicate() == ICmpInst::ICMP_SLT && Op1CV == 0) ||
(ICI->getPredicate() == ICmpInst::ICMP_SGT &&Op1CV.isAllOnesValue())) {
if (!DoXform) return ICI;
Value *In = ICI->getOperand(0);
Value *Sh = ConstantInt::get(In->getType(),
In->getType()->getScalarSizeInBits()-1);
In = Builder->CreateLShr(In, Sh, In->getName()+".lobit");
if (In->getType() != CI.getType())
In = Builder->CreateIntCast(In, CI.getType(), false/*ZExt*/);
if (ICI->getPredicate() == ICmpInst::ICMP_SGT) {
Constant *One = ConstantInt::get(In->getType(), 1);
In = Builder->CreateXor(In, One, In->getName()+".not");
}
return ReplaceInstUsesWith(CI, In);
}
// zext (X == 0) to i32 --> X^1 iff X has only the low bit set.
// zext (X == 0) to i32 --> (X>>1)^1 iff X has only the 2nd bit set.
// zext (X == 1) to i32 --> X iff X has only the low bit set.
// zext (X == 2) to i32 --> X>>1 iff X has only the 2nd bit set.
// zext (X != 0) to i32 --> X iff X has only the low bit set.
// zext (X != 0) to i32 --> X>>1 iff X has only the 2nd bit set.
// zext (X != 1) to i32 --> X^1 iff X has only the low bit set.
// zext (X != 2) to i32 --> (X>>1)^1 iff X has only the 2nd bit set.
if ((Op1CV == 0 || Op1CV.isPowerOf2()) &&
// This only works for EQ and NE
ICI->isEquality()) {
// If Op1C some other power of two, convert:
uint32_t BitWidth = Op1C->getType()->getBitWidth();
APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
computeKnownBits(ICI->getOperand(0), KnownZero, KnownOne, 0, &CI);
APInt KnownZeroMask(~KnownZero);
if (KnownZeroMask.isPowerOf2()) { // Exactly 1 possible 1?
if (!DoXform) return ICI;
bool isNE = ICI->getPredicate() == ICmpInst::ICMP_NE;
if (Op1CV != 0 && (Op1CV != KnownZeroMask)) {
// (X&4) == 2 --> false
// (X&4) != 2 --> true
Constant *Res = ConstantInt::get(Type::getInt1Ty(CI.getContext()),
isNE);
Res = ConstantExpr::getZExt(Res, CI.getType());
return ReplaceInstUsesWith(CI, Res);
}
uint32_t ShiftAmt = KnownZeroMask.logBase2();
Value *In = ICI->getOperand(0);
if (ShiftAmt) {
// Perform a logical shr by shiftamt.
// Insert the shift to put the result in the low bit.
In = Builder->CreateLShr(In, ConstantInt::get(In->getType(),ShiftAmt),
In->getName()+".lobit");
}
if ((Op1CV != 0) == isNE) { // Toggle the low bit.
Constant *One = ConstantInt::get(In->getType(), 1);
In = Builder->CreateXor(In, One);
}
if (CI.getType() == In->getType())
return ReplaceInstUsesWith(CI, In);
return CastInst::CreateIntegerCast(In, CI.getType(), false/*ZExt*/);
}
}
}
// icmp ne A, B is equal to xor A, B when A and B only really have one bit.
// It is also profitable to transform icmp eq into not(xor(A, B)) because that
// may lead to additional simplifications.
if (ICI->isEquality() && CI.getType() == ICI->getOperand(0)->getType()) {
if (IntegerType *ITy = dyn_cast<IntegerType>(CI.getType())) {
uint32_t BitWidth = ITy->getBitWidth();
Value *LHS = ICI->getOperand(0);
Value *RHS = ICI->getOperand(1);
APInt KnownZeroLHS(BitWidth, 0), KnownOneLHS(BitWidth, 0);
APInt KnownZeroRHS(BitWidth, 0), KnownOneRHS(BitWidth, 0);
computeKnownBits(LHS, KnownZeroLHS, KnownOneLHS, 0, &CI);
computeKnownBits(RHS, KnownZeroRHS, KnownOneRHS, 0, &CI);
if (KnownZeroLHS == KnownZeroRHS && KnownOneLHS == KnownOneRHS) {
APInt KnownBits = KnownZeroLHS | KnownOneLHS;
APInt UnknownBit = ~KnownBits;
if (UnknownBit.countPopulation() == 1) {
if (!DoXform) return ICI;
Value *Result = Builder->CreateXor(LHS, RHS);
// Mask off any bits that are set and won't be shifted away.
if (KnownOneLHS.uge(UnknownBit))
Result = Builder->CreateAnd(Result,
ConstantInt::get(ITy, UnknownBit));
// Shift the bit we're testing down to the lsb.
Result = Builder->CreateLShr(
Result, ConstantInt::get(ITy, UnknownBit.countTrailingZeros()));
if (ICI->getPredicate() == ICmpInst::ICMP_EQ)
Result = Builder->CreateXor(Result, ConstantInt::get(ITy, 1));
Result->takeName(ICI);
return ReplaceInstUsesWith(CI, Result);
}
}
}
}
return nullptr;
}
/// CanEvaluateZExtd - Determine if the specified value can be computed in the
/// specified wider type and produce the same low bits. If not, return false.
///
/// If this function returns true, it can also return a non-zero number of bits
/// (in BitsToClear) which indicates that the value it computes is correct for
/// the zero extend, but that the additional BitsToClear bits need to be zero'd
/// out. For example, to promote something like:
///
/// %B = trunc i64 %A to i32
/// %C = lshr i32 %B, 8
/// %E = zext i32 %C to i64
///
/// CanEvaluateZExtd for the 'lshr' will return true, and BitsToClear will be
/// set to 8 to indicate that the promoted value needs to have bits 24-31
/// cleared in addition to bits 32-63. Since an 'and' will be generated to
/// clear the top bits anyway, doing this has no extra cost.
///
/// This function works on both vectors and scalars.
static bool CanEvaluateZExtd(Value *V, Type *Ty, unsigned &BitsToClear,
InstCombiner &IC, Instruction *CxtI) {
BitsToClear = 0;
if (isa<Constant>(V))
return true;
Instruction *I = dyn_cast<Instruction>(V);
if (!I) return false;
// If the input is a truncate from the destination type, we can trivially
// eliminate it.
if (isa<TruncInst>(I) && I->getOperand(0)->getType() == Ty)
return true;
// We can't extend or shrink something that has multiple uses: doing so would
// require duplicating the instruction in general, which isn't profitable.
if (!I->hasOneUse()) return false;
unsigned Opc = I->getOpcode(), Tmp;
switch (Opc) {
case Instruction::ZExt: // zext(zext(x)) -> zext(x).
case Instruction::SExt: // zext(sext(x)) -> sext(x).
case Instruction::Trunc: // zext(trunc(x)) -> trunc(x) or zext(x)
return true;
case Instruction::And:
case Instruction::Or:
case Instruction::Xor:
case Instruction::Add:
case Instruction::Sub:
case Instruction::Mul:
if (!CanEvaluateZExtd(I->getOperand(0), Ty, BitsToClear, IC, CxtI) ||
!CanEvaluateZExtd(I->getOperand(1), Ty, Tmp, IC, CxtI))
return false;
// These can all be promoted if neither operand has 'bits to clear'.
if (BitsToClear == 0 && Tmp == 0)
return true;
// If the operation is an AND/OR/XOR and the bits to clear are zero in the
// other side, BitsToClear is ok.
if (Tmp == 0 &&
(Opc == Instruction::And || Opc == Instruction::Or ||
Opc == Instruction::Xor)) {
// We use MaskedValueIsZero here for generality, but the case we care
// about the most is constant RHS.
unsigned VSize = V->getType()->getScalarSizeInBits();
if (IC.MaskedValueIsZero(I->getOperand(1),
APInt::getHighBitsSet(VSize, BitsToClear),
0, CxtI))
return true;
}
// Otherwise, we don't know how to analyze this BitsToClear case yet.
return false;
case Instruction::Shl:
// We can promote shl(x, cst) if we can promote x. Since shl overwrites the
// upper bits we can reduce BitsToClear by the shift amount.
if (ConstantInt *Amt = dyn_cast<ConstantInt>(I->getOperand(1))) {
if (!CanEvaluateZExtd(I->getOperand(0), Ty, BitsToClear, IC, CxtI))
return false;
uint64_t ShiftAmt = Amt->getZExtValue();
BitsToClear = ShiftAmt < BitsToClear ? BitsToClear - ShiftAmt : 0;
return true;
}
return false;
case Instruction::LShr:
// We can promote lshr(x, cst) if we can promote x. This requires the
// ultimate 'and' to clear out the high zero bits we're clearing out though.
if (ConstantInt *Amt = dyn_cast<ConstantInt>(I->getOperand(1))) {
if (!CanEvaluateZExtd(I->getOperand(0), Ty, BitsToClear, IC, CxtI))
return false;
BitsToClear += Amt->getZExtValue();
if (BitsToClear > V->getType()->getScalarSizeInBits())
BitsToClear = V->getType()->getScalarSizeInBits();
return true;
}
// Cannot promote variable LSHR.
return false;
case Instruction::Select:
if (!CanEvaluateZExtd(I->getOperand(1), Ty, Tmp, IC, CxtI) ||
!CanEvaluateZExtd(I->getOperand(2), Ty, BitsToClear, IC, CxtI) ||
// TODO: If important, we could handle the case when the BitsToClear are
// known zero in the disagreeing side.
Tmp != BitsToClear)
return false;
return true;
case Instruction::PHI: {
// We can change a phi if we can change all operands. Note that we never
// get into trouble with cyclic PHIs here because we only consider
// instructions with a single use.
PHINode *PN = cast<PHINode>(I);
if (!CanEvaluateZExtd(PN->getIncomingValue(0), Ty, BitsToClear, IC, CxtI))
return false;
for (unsigned i = 1, e = PN->getNumIncomingValues(); i != e; ++i)
if (!CanEvaluateZExtd(PN->getIncomingValue(i), Ty, Tmp, IC, CxtI) ||
// TODO: If important, we could handle the case when the BitsToClear
// are known zero in the disagreeing input.
Tmp != BitsToClear)
return false;
return true;
}
default:
// TODO: Can handle more cases here.
return false;
}
}
Instruction *InstCombiner::visitZExt(ZExtInst &CI) {
// If this zero extend is only used by a truncate, let the truncate be
// eliminated before we try to optimize this zext.
if (CI.hasOneUse() && isa<TruncInst>(CI.user_back()))
return nullptr;
// If one of the common conversion will work, do it.
if (Instruction *Result = commonCastTransforms(CI))
return Result;
// See if we can simplify any instructions used by the input whose sole
// purpose is to compute bits we don't care about.
if (SimplifyDemandedInstructionBits(CI))
return &CI;
Value *Src = CI.getOperand(0);
Type *SrcTy = Src->getType(), *DestTy = CI.getType();
// Attempt to extend the entire input expression tree to the destination
// type. Only do this if the dest type is a simple type, don't convert the
// expression tree to something weird like i93 unless the source is also
// strange.
unsigned BitsToClear;
if ((DestTy->isVectorTy() || ShouldChangeType(SrcTy, DestTy)) &&
CanEvaluateZExtd(Src, DestTy, BitsToClear, *this, &CI)) {
assert(BitsToClear < SrcTy->getScalarSizeInBits() &&
"Unreasonable BitsToClear");
// Okay, we can transform this! Insert the new expression now.
DEBUG(dbgs() << "ICE: EvaluateInDifferentType converting expression type"
" to avoid zero extend: " << CI);
Value *Res = EvaluateInDifferentType(Src, DestTy, false);
assert(Res->getType() == DestTy);
uint32_t SrcBitsKept = SrcTy->getScalarSizeInBits()-BitsToClear;
uint32_t DestBitSize = DestTy->getScalarSizeInBits();
// If the high bits are already filled with zeros, just replace this
// cast with the result.
if (MaskedValueIsZero(Res,
APInt::getHighBitsSet(DestBitSize,
DestBitSize-SrcBitsKept),
0, &CI))
return ReplaceInstUsesWith(CI, Res);
// We need to emit an AND to clear the high bits.
Constant *C = ConstantInt::get(Res->getType(),
APInt::getLowBitsSet(DestBitSize, SrcBitsKept));
return BinaryOperator::CreateAnd(Res, C);
}
// If this is a TRUNC followed by a ZEXT then we are dealing with integral
// types and if the sizes are just right we can convert this into a logical
// 'and' which will be much cheaper than the pair of casts.
if (TruncInst *CSrc = dyn_cast<TruncInst>(Src)) { // A->B->C cast
// TODO: Subsume this into EvaluateInDifferentType.
// Get the sizes of the types involved. We know that the intermediate type
// will be smaller than A or C, but don't know the relation between A and C.
Value *A = CSrc->getOperand(0);
unsigned SrcSize = A->getType()->getScalarSizeInBits();
unsigned MidSize = CSrc->getType()->getScalarSizeInBits();
unsigned DstSize = CI.getType()->getScalarSizeInBits();
// If we're actually extending zero bits, then if
// SrcSize < DstSize: zext(a & mask)
// SrcSize == DstSize: a & mask
// SrcSize > DstSize: trunc(a) & mask
if (SrcSize < DstSize) {
APInt AndValue(APInt::getLowBitsSet(SrcSize, MidSize));
Constant *AndConst = ConstantInt::get(A->getType(), AndValue);
Value *And = Builder->CreateAnd(A, AndConst, CSrc->getName()+".mask");
return new ZExtInst(And, CI.getType());
}
if (SrcSize == DstSize) {
APInt AndValue(APInt::getLowBitsSet(SrcSize, MidSize));
return BinaryOperator::CreateAnd(A, ConstantInt::get(A->getType(),
AndValue));
}
if (SrcSize > DstSize) {
Value *Trunc = Builder->CreateTrunc(A, CI.getType());
APInt AndValue(APInt::getLowBitsSet(DstSize, MidSize));
return BinaryOperator::CreateAnd(Trunc,
ConstantInt::get(Trunc->getType(),
AndValue));
}
}
if (ICmpInst *ICI = dyn_cast<ICmpInst>(Src))
return transformZExtICmp(ICI, CI);
BinaryOperator *SrcI = dyn_cast<BinaryOperator>(Src);
if (SrcI && SrcI->getOpcode() == Instruction::Or) {
// zext (or icmp, icmp) --> or (zext icmp), (zext icmp) if at least one
// of the (zext icmp) will be transformed.
ICmpInst *LHS = dyn_cast<ICmpInst>(SrcI->getOperand(0));
ICmpInst *RHS = dyn_cast<ICmpInst>(SrcI->getOperand(1));
if (LHS && RHS && LHS->hasOneUse() && RHS->hasOneUse() &&
(transformZExtICmp(LHS, CI, false) ||
transformZExtICmp(RHS, CI, false))) {
Value *LCast = Builder->CreateZExt(LHS, CI.getType(), LHS->getName());
Value *RCast = Builder->CreateZExt(RHS, CI.getType(), RHS->getName());
return BinaryOperator::Create(Instruction::Or, LCast, RCast);
}
}
// zext(trunc(X) & C) -> (X & zext(C)).
Constant *C;
Value *X;
if (SrcI &&
match(SrcI, m_OneUse(m_And(m_Trunc(m_Value(X)), m_Constant(C)))) &&
X->getType() == CI.getType())
return BinaryOperator::CreateAnd(X, ConstantExpr::getZExt(C, CI.getType()));
// zext((trunc(X) & C) ^ C) -> ((X & zext(C)) ^ zext(C)).
Value *And;
if (SrcI && match(SrcI, m_OneUse(m_Xor(m_Value(And), m_Constant(C)))) &&
match(And, m_OneUse(m_And(m_Trunc(m_Value(X)), m_Specific(C)))) &&
X->getType() == CI.getType()) {
Constant *ZC = ConstantExpr::getZExt(C, CI.getType());
return BinaryOperator::CreateXor(Builder->CreateAnd(X, ZC), ZC);
}
// zext (xor i1 X, true) to i32 --> xor (zext i1 X to i32), 1
if (SrcI && SrcI->hasOneUse() &&
SrcI->getType()->getScalarType()->isIntegerTy(1) &&
match(SrcI, m_Not(m_Value(X))) && (!X->hasOneUse() || !isa<CmpInst>(X))) {
Value *New = Builder->CreateZExt(X, CI.getType());
return BinaryOperator::CreateXor(New, ConstantInt::get(CI.getType(), 1));
}
return nullptr;
}
/// transformSExtICmp - Transform (sext icmp) to bitwise / integer operations
/// in order to eliminate the icmp.
Instruction *InstCombiner::transformSExtICmp(ICmpInst *ICI, Instruction &CI) {
Value *Op0 = ICI->getOperand(0), *Op1 = ICI->getOperand(1);
ICmpInst::Predicate Pred = ICI->getPredicate();
// Don't bother if Op1 isn't of vector or integer type.
if (!Op1->getType()->isIntOrIntVectorTy())
return nullptr;
if (Constant *Op1C = dyn_cast<Constant>(Op1)) {
// (x <s 0) ? -1 : 0 -> ashr x, 31 -> all ones if negative
// (x >s -1) ? -1 : 0 -> not (ashr x, 31) -> all ones if positive
if ((Pred == ICmpInst::ICMP_SLT && Op1C->isNullValue()) ||
(Pred == ICmpInst::ICMP_SGT && Op1C->isAllOnesValue())) {
Value *Sh = ConstantInt::get(Op0->getType(),
Op0->getType()->getScalarSizeInBits()-1);
Value *In = Builder->CreateAShr(Op0, Sh, Op0->getName()+".lobit");
if (In->getType() != CI.getType())
In = Builder->CreateIntCast(In, CI.getType(), true/*SExt*/);
if (Pred == ICmpInst::ICMP_SGT)
In = Builder->CreateNot(In, In->getName()+".not");
return ReplaceInstUsesWith(CI, In);
}
}
if (ConstantInt *Op1C = dyn_cast<ConstantInt>(Op1)) {
// If we know that only one bit of the LHS of the icmp can be set and we
// have an equality comparison with zero or a power of 2, we can transform
// the icmp and sext into bitwise/integer operations.
if (ICI->hasOneUse() &&
ICI->isEquality() && (Op1C->isZero() || Op1C->getValue().isPowerOf2())){
unsigned BitWidth = Op1C->getType()->getBitWidth();
APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
computeKnownBits(Op0, KnownZero, KnownOne, 0, &CI);
APInt KnownZeroMask(~KnownZero);
if (KnownZeroMask.isPowerOf2()) {
Value *In = ICI->getOperand(0);
// If the icmp tests for a known zero bit we can constant fold it.
if (!Op1C->isZero() && Op1C->getValue() != KnownZeroMask) {
Value *V = Pred == ICmpInst::ICMP_NE ?
ConstantInt::getAllOnesValue(CI.getType()) :
ConstantInt::getNullValue(CI.getType());
return ReplaceInstUsesWith(CI, V);
}
if (!Op1C->isZero() == (Pred == ICmpInst::ICMP_NE)) {
// sext ((x & 2^n) == 0) -> (x >> n) - 1
// sext ((x & 2^n) != 2^n) -> (x >> n) - 1
unsigned ShiftAmt = KnownZeroMask.countTrailingZeros();
// Perform a right shift to place the desired bit in the LSB.
if (ShiftAmt)
In = Builder->CreateLShr(In,
ConstantInt::get(In->getType(), ShiftAmt));
// At this point "In" is either 1 or 0. Subtract 1 to turn
// {1, 0} -> {0, -1}.
In = Builder->CreateAdd(In,
ConstantInt::getAllOnesValue(In->getType()),
"sext");
} else {
// sext ((x & 2^n) != 0) -> (x << bitwidth-n) a>> bitwidth-1
// sext ((x & 2^n) == 2^n) -> (x << bitwidth-n) a>> bitwidth-1
unsigned ShiftAmt = KnownZeroMask.countLeadingZeros();
// Perform a left shift to place the desired bit in the MSB.
if (ShiftAmt)
In = Builder->CreateShl(In,
ConstantInt::get(In->getType(), ShiftAmt));
// Distribute the bit over the whole bit width.
In = Builder->CreateAShr(In, ConstantInt::get(In->getType(),
BitWidth - 1), "sext");
}
if (CI.getType() == In->getType())
return ReplaceInstUsesWith(CI, In);
return CastInst::CreateIntegerCast(In, CI.getType(), true/*SExt*/);
}
}
}
return nullptr;
}
/// CanEvaluateSExtd - Return true if we can take the specified value
/// and return it as type Ty without inserting any new casts and without
/// changing the value of the common low bits. This is used by code that tries
/// to promote integer operations to a wider types will allow us to eliminate
/// the extension.
///
/// This function works on both vectors and scalars.
///
static bool CanEvaluateSExtd(Value *V, Type *Ty) {
assert(V->getType()->getScalarSizeInBits() < Ty->getScalarSizeInBits() &&
"Can't sign extend type to a smaller type");
// If this is a constant, it can be trivially promoted.
if (isa<Constant>(V))
return true;
Instruction *I = dyn_cast<Instruction>(V);
if (!I) return false;
// If this is a truncate from the dest type, we can trivially eliminate it.
if (isa<TruncInst>(I) && I->getOperand(0)->getType() == Ty)
return true;
// We can't extend or shrink something that has multiple uses: doing so would
// require duplicating the instruction in general, which isn't profitable.
if (!I->hasOneUse()) return false;
switch (I->getOpcode()) {
case Instruction::SExt: // sext(sext(x)) -> sext(x)
case Instruction::ZExt: // sext(zext(x)) -> zext(x)
case Instruction::Trunc: // sext(trunc(x)) -> trunc(x) or sext(x)
return true;
case Instruction::And:
case Instruction::Or:
case Instruction::Xor:
case Instruction::Add:
case Instruction::Sub:
case Instruction::Mul:
// These operators can all arbitrarily be extended if their inputs can.
return CanEvaluateSExtd(I->getOperand(0), Ty) &&
CanEvaluateSExtd(I->getOperand(1), Ty);
//case Instruction::Shl: TODO
//case Instruction::LShr: TODO
case Instruction::Select:
return CanEvaluateSExtd(I->getOperand(1), Ty) &&
CanEvaluateSExtd(I->getOperand(2), Ty);
case Instruction::PHI: {
// We can change a phi if we can change all operands. Note that we never
// get into trouble with cyclic PHIs here because we only consider
// instructions with a single use.
PHINode *PN = cast<PHINode>(I);
for (Value *IncValue : PN->incoming_values())
if (!CanEvaluateSExtd(IncValue, Ty)) return false;
return true;
}
default:
// TODO: Can handle more cases here.
break;
}
return false;
}
Instruction *InstCombiner::visitSExt(SExtInst &CI) {
// If this sign extend is only used by a truncate, let the truncate be
// eliminated before we try to optimize this sext.
if (CI.hasOneUse() && isa<TruncInst>(CI.user_back()))
return nullptr;
if (Instruction *I = commonCastTransforms(CI))
return I;
// See if we can simplify any instructions used by the input whose sole
// purpose is to compute bits we don't care about.
if (SimplifyDemandedInstructionBits(CI))
return &CI;
Value *Src = CI.getOperand(0);
Type *SrcTy = Src->getType(), *DestTy = CI.getType();
// If we know that the value being extended is positive, we can use a zext
// instead.
bool KnownZero, KnownOne;
ComputeSignBit(Src, KnownZero, KnownOne, 0, &CI);
if (KnownZero) {
Value *ZExt = Builder->CreateZExt(Src, DestTy);
return ReplaceInstUsesWith(CI, ZExt);
}
// Attempt to extend the entire input expression tree to the destination
// type. Only do this if the dest type is a simple type, don't convert the
// expression tree to something weird like i93 unless the source is also
// strange.
if ((DestTy->isVectorTy() || ShouldChangeType(SrcTy, DestTy)) &&
CanEvaluateSExtd(Src, DestTy)) {
// Okay, we can transform this! Insert the new expression now.
DEBUG(dbgs() << "ICE: EvaluateInDifferentType converting expression type"
" to avoid sign extend: " << CI);
Value *Res = EvaluateInDifferentType(Src, DestTy, true);
assert(Res->getType() == DestTy);
uint32_t SrcBitSize = SrcTy->getScalarSizeInBits();
uint32_t DestBitSize = DestTy->getScalarSizeInBits();
// If the high bits are already filled with sign bit, just replace this
// cast with the result.
if (ComputeNumSignBits(Res, 0, &CI) > DestBitSize - SrcBitSize)
return ReplaceInstUsesWith(CI, Res);
// We need to emit a shl + ashr to do the sign extend.
Value *ShAmt = ConstantInt::get(DestTy, DestBitSize-SrcBitSize);
return BinaryOperator::CreateAShr(Builder->CreateShl(Res, ShAmt, "sext"),
ShAmt);
}
// If this input is a trunc from our destination, then turn sext(trunc(x))
// into shifts.
if (TruncInst *TI = dyn_cast<TruncInst>(Src))
if (TI->hasOneUse() && TI->getOperand(0)->getType() == DestTy) {
uint32_t SrcBitSize = SrcTy->getScalarSizeInBits();
uint32_t DestBitSize = DestTy->getScalarSizeInBits();
// We need to emit a shl + ashr to do the sign extend.
Value *ShAmt = ConstantInt::get(DestTy, DestBitSize-SrcBitSize);
Value *Res = Builder->CreateShl(TI->getOperand(0), ShAmt, "sext");
return BinaryOperator::CreateAShr(Res, ShAmt);
}
if (ICmpInst *ICI = dyn_cast<ICmpInst>(Src))
return transformSExtICmp(ICI, CI);
// If the input is a shl/ashr pair of a same constant, then this is a sign
// extension from a smaller value. If we could trust arbitrary bitwidth
// integers, we could turn this into a truncate to the smaller bit and then
// use a sext for the whole extension. Since we don't, look deeper and check
// for a truncate. If the source and dest are the same type, eliminate the
// trunc and extend and just do shifts. For example, turn:
// %a = trunc i32 %i to i8
// %b = shl i8 %a, 6
// %c = ashr i8 %b, 6
// %d = sext i8 %c to i32
// into:
// %a = shl i32 %i, 30
// %d = ashr i32 %a, 30
Value *A = nullptr;
// TODO: Eventually this could be subsumed by EvaluateInDifferentType.
ConstantInt *BA = nullptr, *CA = nullptr;
if (match(Src, m_AShr(m_Shl(m_Trunc(m_Value(A)), m_ConstantInt(BA)),
m_ConstantInt(CA))) &&
BA == CA && A->getType() == CI.getType()) {
unsigned MidSize = Src->getType()->getScalarSizeInBits();
unsigned SrcDstSize = CI.getType()->getScalarSizeInBits();
unsigned ShAmt = CA->getZExtValue()+SrcDstSize-MidSize;
Constant *ShAmtV = ConstantInt::get(CI.getType(), ShAmt);
A = Builder->CreateShl(A, ShAmtV, CI.getName());
return BinaryOperator::CreateAShr(A, ShAmtV);
}
return nullptr;
}
/// FitsInFPType - Return a Constant* for the specified FP constant if it fits
/// in the specified FP type without changing its value.
static Constant *FitsInFPType(ConstantFP *CFP, const fltSemantics &Sem) {
bool losesInfo;
APFloat F = CFP->getValueAPF();
(void)F.convert(Sem, APFloat::rmNearestTiesToEven, &losesInfo);
if (!losesInfo)
return ConstantFP::get(CFP->getContext(), F);
return nullptr;
}
/// LookThroughFPExtensions - If this is an fp extension instruction, look
/// through it until we get the source value.
static Value *LookThroughFPExtensions(Value *V) {
if (Instruction *I = dyn_cast<Instruction>(V))
if (I->getOpcode() == Instruction::FPExt)
return LookThroughFPExtensions(I->getOperand(0));
// If this value is a constant, return the constant in the smallest FP type
// that can accurately represent it. This allows us to turn
// (float)((double)X+2.0) into x+2.0f.
if (ConstantFP *CFP = dyn_cast<ConstantFP>(V)) {
if (CFP->getType() == Type::getPPC_FP128Ty(V->getContext()))
return V; // No constant folding of this.
// See if the value can be truncated to half and then reextended.
if (Value *V = FitsInFPType(CFP, APFloat::IEEEhalf))
return V;
// See if the value can be truncated to float and then reextended.
if (Value *V = FitsInFPType(CFP, APFloat::IEEEsingle))
return V;
if (CFP->getType()->isDoubleTy())
return V; // Won't shrink.
if (Value *V = FitsInFPType(CFP, APFloat::IEEEdouble))
return V;
// Don't try to shrink to various long double types.
}
return V;
}
Instruction *InstCombiner::visitFPTrunc(FPTruncInst &CI) {
if (Instruction *I = commonCastTransforms(CI))
return I;
// If we have fptrunc(OpI (fpextend x), (fpextend y)), we would like to
// simpilify this expression to avoid one or more of the trunc/extend
// operations if we can do so without changing the numerical results.
//
// The exact manner in which the widths of the operands interact to limit
// what we can and cannot do safely varies from operation to operation, and
// is explained below in the various case statements.
BinaryOperator *OpI = dyn_cast<BinaryOperator>(CI.getOperand(0));
if (OpI && OpI->hasOneUse()) {
Value *LHSOrig = LookThroughFPExtensions(OpI->getOperand(0));
Value *RHSOrig = LookThroughFPExtensions(OpI->getOperand(1));
unsigned OpWidth = OpI->getType()->getFPMantissaWidth();
unsigned LHSWidth = LHSOrig->getType()->getFPMantissaWidth();
unsigned RHSWidth = RHSOrig->getType()->getFPMantissaWidth();
unsigned SrcWidth = std::max(LHSWidth, RHSWidth);
unsigned DstWidth = CI.getType()->getFPMantissaWidth();
switch (OpI->getOpcode()) {
default: break;
case Instruction::FAdd:
case Instruction::FSub:
// For addition and subtraction, the infinitely precise result can
// essentially be arbitrarily wide; proving that double rounding
// will not occur because the result of OpI is exact (as we will for
// FMul, for example) is hopeless. However, we *can* nonetheless
// frequently know that double rounding cannot occur (or that it is
// innocuous) by taking advantage of the specific structure of
// infinitely-precise results that admit double rounding.
//
// Specifically, if OpWidth >= 2*DstWdith+1 and DstWidth is sufficient
// to represent both sources, we can guarantee that the double
// rounding is innocuous (See p50 of Figueroa's 2000 PhD thesis,
// "A Rigorous Framework for Fully Supporting the IEEE Standard ..."
// for proof of this fact).
//
// Note: Figueroa does not consider the case where DstFormat !=
// SrcFormat. It's possible (likely even!) that this analysis
// could be tightened for those cases, but they are rare (the main
// case of interest here is (float)((double)float + float)).
if (OpWidth >= 2*DstWidth+1 && DstWidth >= SrcWidth) {
if (LHSOrig->getType() != CI.getType())
LHSOrig = Builder->CreateFPExt(LHSOrig, CI.getType());
if (RHSOrig->getType() != CI.getType())
RHSOrig = Builder->CreateFPExt(RHSOrig, CI.getType());
Instruction *RI =
BinaryOperator::Create(OpI->getOpcode(), LHSOrig, RHSOrig);
RI->copyFastMathFlags(OpI);
return RI;
}
break;
case Instruction::FMul:
// For multiplication, the infinitely precise result has at most
// LHSWidth + RHSWidth significant bits; if OpWidth is sufficient
// that such a value can be exactly represented, then no double
// rounding can possibly occur; we can safely perform the operation
// in the destination format if it can represent both sources.
if (OpWidth >= LHSWidth + RHSWidth && DstWidth >= SrcWidth) {
if (LHSOrig->getType() != CI.getType())
LHSOrig = Builder->CreateFPExt(LHSOrig, CI.getType());
if (RHSOrig->getType() != CI.getType())
RHSOrig = Builder->CreateFPExt(RHSOrig, CI.getType());
Instruction *RI =
BinaryOperator::CreateFMul(LHSOrig, RHSOrig);
RI->copyFastMathFlags(OpI);
return RI;
}
break;
case Instruction::FDiv:
// For division, we use again use the bound from Figueroa's
// dissertation. I am entirely certain that this bound can be
// tightened in the unbalanced operand case by an analysis based on
// the diophantine rational approximation bound, but the well-known
// condition used here is a good conservative first pass.
// TODO: Tighten bound via rigorous analysis of the unbalanced case.
if (OpWidth >= 2*DstWidth && DstWidth >= SrcWidth) {
if (LHSOrig->getType() != CI.getType())
LHSOrig = Builder->CreateFPExt(LHSOrig, CI.getType());
if (RHSOrig->getType() != CI.getType())
RHSOrig = Builder->CreateFPExt(RHSOrig, CI.getType());
Instruction *RI =
BinaryOperator::CreateFDiv(LHSOrig, RHSOrig);
RI->copyFastMathFlags(OpI);
return RI;
}
break;
case Instruction::FRem:
// Remainder is straightforward. Remainder is always exact, so the
// type of OpI doesn't enter into things at all. We simply evaluate
// in whichever source type is larger, then convert to the
// destination type.
if (SrcWidth == OpWidth)
break;
if (LHSWidth < SrcWidth)
LHSOrig = Builder->CreateFPExt(LHSOrig, RHSOrig->getType());
else if (RHSWidth <= SrcWidth)
RHSOrig = Builder->CreateFPExt(RHSOrig, LHSOrig->getType());
if (LHSOrig != OpI->getOperand(0) || RHSOrig != OpI->getOperand(1)) {
Value *ExactResult = Builder->CreateFRem(LHSOrig, RHSOrig);
if (Instruction *RI = dyn_cast<Instruction>(ExactResult))
RI->copyFastMathFlags(OpI);
return CastInst::CreateFPCast(ExactResult, CI.getType());
}
}
// (fptrunc (fneg x)) -> (fneg (fptrunc x))
if (BinaryOperator::isFNeg(OpI)) {
Value *InnerTrunc = Builder->CreateFPTrunc(OpI->getOperand(1),
CI.getType());
Instruction *RI = BinaryOperator::CreateFNeg(InnerTrunc);
RI->copyFastMathFlags(OpI);
return RI;
}
}
// (fptrunc (select cond, R1, Cst)) -->
// (select cond, (fptrunc R1), (fptrunc Cst))
SelectInst *SI = dyn_cast<SelectInst>(CI.getOperand(0));
if (SI &&
(isa<ConstantFP>(SI->getOperand(1)) ||
isa<ConstantFP>(SI->getOperand(2)))) {
Value *LHSTrunc = Builder->CreateFPTrunc(SI->getOperand(1),
CI.getType());
Value *RHSTrunc = Builder->CreateFPTrunc(SI->getOperand(2),
CI.getType());
return SelectInst::Create(SI->getOperand(0), LHSTrunc, RHSTrunc);
}
IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI.getOperand(0));
if (II) {
switch (II->getIntrinsicID()) {
default: break;
case Intrinsic::fabs: {
// (fptrunc (fabs x)) -> (fabs (fptrunc x))
Value *InnerTrunc = Builder->CreateFPTrunc(II->getArgOperand(0),
CI.getType());
Type *IntrinsicType[] = { CI.getType() };
Function *Overload =
Intrinsic::getDeclaration(CI.getParent()->getParent()->getParent(),
II->getIntrinsicID(), IntrinsicType);
Value *Args[] = { InnerTrunc };
return CallInst::Create(Overload, Args, II->getName());
}
}
}
return nullptr;
}
Instruction *InstCombiner::visitFPExt(CastInst &CI) {
return commonCastTransforms(CI);
}
// fpto{s/u}i({u/s}itofp(X)) --> X or zext(X) or sext(X) or trunc(X)
// This is safe if the intermediate type has enough bits in its mantissa to
// accurately represent all values of X. For example, this won't work with
// i64 -> float -> i64.
Instruction *InstCombiner::FoldItoFPtoI(Instruction &FI) {
if (!isa<UIToFPInst>(FI.getOperand(0)) && !isa<SIToFPInst>(FI.getOperand(0)))
return nullptr;
Instruction *OpI = cast<Instruction>(FI.getOperand(0));
Value *SrcI = OpI->getOperand(0);
Type *FITy = FI.getType();
Type *OpITy = OpI->getType();
Type *SrcTy = SrcI->getType();
bool IsInputSigned = isa<SIToFPInst>(OpI);
bool IsOutputSigned = isa<FPToSIInst>(FI);
// We can safely assume the conversion won't overflow the output range,
// because (for example) (uint8_t)18293.f is undefined behavior.
// Since we can assume the conversion won't overflow, our decision as to
// whether the input will fit in the float should depend on the minimum
// of the input range and output range.
// This means this is also safe for a signed input and unsigned output, since
// a negative input would lead to undefined behavior.
int InputSize = (int)SrcTy->getScalarSizeInBits() - IsInputSigned;
int OutputSize = (int)FITy->getScalarSizeInBits() - IsOutputSigned;
int ActualSize = std::min(InputSize, OutputSize);
if (ActualSize <= OpITy->getFPMantissaWidth()) {
if (FITy->getScalarSizeInBits() > SrcTy->getScalarSizeInBits()) {
if (IsInputSigned && IsOutputSigned)
return new SExtInst(SrcI, FITy);
return new ZExtInst(SrcI, FITy);
}
if (FITy->getScalarSizeInBits() < SrcTy->getScalarSizeInBits())
return new TruncInst(SrcI, FITy);
if (SrcTy == FITy)
return ReplaceInstUsesWith(FI, SrcI);
return new BitCastInst(SrcI, FITy);
}
return nullptr;
}
Instruction *InstCombiner::visitFPToUI(FPToUIInst &FI) {
Instruction *OpI = dyn_cast<Instruction>(FI.getOperand(0));
if (!OpI)
return commonCastTransforms(FI);
if (Instruction *I = FoldItoFPtoI(FI))
return I;
return commonCastTransforms(FI);
}
Instruction *InstCombiner::visitFPToSI(FPToSIInst &FI) {
Instruction *OpI = dyn_cast<Instruction>(FI.getOperand(0));
if (!OpI)
return commonCastTransforms(FI);
if (Instruction *I = FoldItoFPtoI(FI))
return I;
return commonCastTransforms(FI);
}
Instruction *InstCombiner::visitUIToFP(CastInst &CI) {
return commonCastTransforms(CI);
}
Instruction *InstCombiner::visitSIToFP(CastInst &CI) {
return commonCastTransforms(CI);
}
Instruction *InstCombiner::visitIntToPtr(IntToPtrInst &CI) {
// If the source integer type is not the intptr_t type for this target, do a
// trunc or zext to the intptr_t type, then inttoptr of it. This allows the
// cast to be exposed to other transforms.
unsigned AS = CI.getAddressSpace();
if (CI.getOperand(0)->getType()->getScalarSizeInBits() !=
DL.getPointerSizeInBits(AS)) {
Type *Ty = DL.getIntPtrType(CI.getContext(), AS);
if (CI.getType()->isVectorTy()) // Handle vectors of pointers.
Ty = VectorType::get(Ty, CI.getType()->getVectorNumElements());
Value *P = Builder->CreateZExtOrTrunc(CI.getOperand(0), Ty);
return new IntToPtrInst(P, CI.getType());
}
if (Instruction *I = commonCastTransforms(CI))
return I;
return nullptr;
}
/// @brief Implement the transforms for cast of pointer (bitcast/ptrtoint)
Instruction *InstCombiner::commonPointerCastTransforms(CastInst &CI) {
Value *Src = CI.getOperand(0);
if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Src)) {
// If casting the result of a getelementptr instruction with no offset, turn
// this into a cast of the original pointer!
if (GEP->hasAllZeroIndices() &&
// HLSL Change Begin.
// Ignore this optimization for pointer bitcast to pass validation.
// TODO: enable this optimization when validation is updated.
0 &&
// HLSL Change End.
// If CI is an addrspacecast and GEP changes the poiner type, merging
// GEP into CI would undo canonicalizing addrspacecast with different
// pointer types, causing infinite loops.
(!isa<AddrSpaceCastInst>(CI) ||
GEP->getType() == GEP->getPointerOperand()->getType())) {
// Changing the cast operand is usually not a good idea but it is safe
// here because the pointer operand is being replaced with another
// pointer operand so the opcode doesn't need to change.
Worklist.Add(GEP);
CI.setOperand(0, GEP->getOperand(0));
return &CI;
}
}
return commonCastTransforms(CI);
}
Instruction *InstCombiner::visitPtrToInt(PtrToIntInst &CI) {
// If the destination integer type is not the intptr_t type for this target,
// do a ptrtoint to intptr_t then do a trunc or zext. This allows the cast
// to be exposed to other transforms.
Type *Ty = CI.getType();
unsigned AS = CI.getPointerAddressSpace();
if (Ty->getScalarSizeInBits() == DL.getPointerSizeInBits(AS))
return commonPointerCastTransforms(CI);
Type *PtrTy = DL.getIntPtrType(CI.getContext(), AS);
if (Ty->isVectorTy()) // Handle vectors of pointers.
PtrTy = VectorType::get(PtrTy, Ty->getVectorNumElements());
Value *P = Builder->CreatePtrToInt(CI.getOperand(0), PtrTy);
return CastInst::CreateIntegerCast(P, Ty, /*isSigned=*/false);
}
/// OptimizeVectorResize - This input value (which is known to have vector type)
/// is being zero extended or truncated to the specified vector type. Try to
/// replace it with a shuffle (and vector/vector bitcast) if possible.
///
/// The source and destination vector types may have different element types.
static Instruction *OptimizeVectorResize(Value *InVal, VectorType *DestTy,
InstCombiner &IC) {
// We can only do this optimization if the output is a multiple of the input
// element size, or the input is a multiple of the output element size.
// Convert the input type to have the same element type as the output.
VectorType *SrcTy = cast<VectorType>(InVal->getType());
if (SrcTy->getElementType() != DestTy->getElementType()) {
// The input types don't need to be identical, but for now they must be the
// same size. There is no specific reason we couldn't handle things like
// <4 x i16> -> <4 x i32> by bitcasting to <2 x i32> but haven't gotten
// there yet.
if (SrcTy->getElementType()->getPrimitiveSizeInBits() !=
DestTy->getElementType()->getPrimitiveSizeInBits())
return nullptr;
SrcTy = VectorType::get(DestTy->getElementType(), SrcTy->getNumElements());
InVal = IC.Builder->CreateBitCast(InVal, SrcTy);
}
// Now that the element types match, get the shuffle mask and RHS of the
// shuffle to use, which depends on whether we're increasing or decreasing the
// size of the input.
SmallVector<uint32_t, 16> ShuffleMask;
Value *V2;
if (SrcTy->getNumElements() > DestTy->getNumElements()) {
// If we're shrinking the number of elements, just shuffle in the low
// elements from the input and use undef as the second shuffle input.
V2 = UndefValue::get(SrcTy);
for (unsigned i = 0, e = DestTy->getNumElements(); i != e; ++i)
ShuffleMask.push_back(i);
} else {
// If we're increasing the number of elements, shuffle in all of the
// elements from InVal and fill the rest of the result elements with zeros
// from a constant zero.
V2 = Constant::getNullValue(SrcTy);
unsigned SrcElts = SrcTy->getNumElements();
for (unsigned i = 0, e = SrcElts; i != e; ++i)
ShuffleMask.push_back(i);
// The excess elements reference the first element of the zero input.
for (unsigned i = 0, e = DestTy->getNumElements()-SrcElts; i != e; ++i)
ShuffleMask.push_back(SrcElts);
}
return new ShuffleVectorInst(InVal, V2,
ConstantDataVector::get(V2->getContext(),
ShuffleMask));
}
static bool isMultipleOfTypeSize(unsigned Value, Type *Ty) {
return Value % Ty->getPrimitiveSizeInBits() == 0;
}
static unsigned getTypeSizeIndex(unsigned Value, Type *Ty) {
return Value / Ty->getPrimitiveSizeInBits();
}
/// CollectInsertionElements - V is a value which is inserted into a vector of
/// VecEltTy. Look through the value to see if we can decompose it into
/// insertions into the vector. See the example in the comment for
/// OptimizeIntegerToVectorInsertions for the pattern this handles.
/// The type of V is always a non-zero multiple of VecEltTy's size.
/// Shift is the number of bits between the lsb of V and the lsb of
/// the vector.
///
/// This returns false if the pattern can't be matched or true if it can,
/// filling in Elements with the elements found here.
static bool CollectInsertionElements(Value *V, unsigned Shift,
SmallVectorImpl<Value *> &Elements,
Type *VecEltTy, bool isBigEndian) {
assert(isMultipleOfTypeSize(Shift, VecEltTy) &&
"Shift should be a multiple of the element type size");
// Undef values never contribute useful bits to the result.
if (isa<UndefValue>(V)) return true;
// If we got down to a value of the right type, we win, try inserting into the
// right element.
if (V->getType() == VecEltTy) {
// Inserting null doesn't actually insert any elements.
if (Constant *C = dyn_cast<Constant>(V))
if (C->isNullValue())
return true;
unsigned ElementIndex = getTypeSizeIndex(Shift, VecEltTy);
if (isBigEndian)
ElementIndex = Elements.size() - ElementIndex - 1;
// Fail if multiple elements are inserted into this slot.
if (Elements[ElementIndex])
return false;
Elements[ElementIndex] = V;
return true;
}
if (Constant *C = dyn_cast<Constant>(V)) {
// Figure out the # elements this provides, and bitcast it or slice it up
// as required.
unsigned NumElts = getTypeSizeIndex(C->getType()->getPrimitiveSizeInBits(),
VecEltTy);
// If the constant is the size of a vector element, we just need to bitcast
// it to the right type so it gets properly inserted.
if (NumElts == 1)
return CollectInsertionElements(ConstantExpr::getBitCast(C, VecEltTy),
Shift, Elements, VecEltTy, isBigEndian);
// Okay, this is a constant that covers multiple elements. Slice it up into
// pieces and insert each element-sized piece into the vector.
if (!isa<IntegerType>(C->getType()))
C = ConstantExpr::getBitCast(C, IntegerType::get(V->getContext(),
C->getType()->getPrimitiveSizeInBits()));
unsigned ElementSize = VecEltTy->getPrimitiveSizeInBits();
Type *ElementIntTy = IntegerType::get(C->getContext(), ElementSize);
for (unsigned i = 0; i != NumElts; ++i) {
unsigned ShiftI = Shift+i*ElementSize;
Constant *Piece = ConstantExpr::getLShr(C, ConstantInt::get(C->getType(),
ShiftI));
Piece = ConstantExpr::getTrunc(Piece, ElementIntTy);
if (!CollectInsertionElements(Piece, ShiftI, Elements, VecEltTy,
isBigEndian))
return false;
}
return true;
}
if (!V->hasOneUse()) return false;
Instruction *I = dyn_cast<Instruction>(V);
if (!I) return false;
switch (I->getOpcode()) {
default: return false; // Unhandled case.
case Instruction::BitCast:
return CollectInsertionElements(I->getOperand(0), Shift, Elements, VecEltTy,
isBigEndian);
case Instruction::ZExt:
if (!isMultipleOfTypeSize(
I->getOperand(0)->getType()->getPrimitiveSizeInBits(),
VecEltTy))
return false;
return CollectInsertionElements(I->getOperand(0), Shift, Elements, VecEltTy,
isBigEndian);
case Instruction::Or:
return CollectInsertionElements(I->getOperand(0), Shift, Elements, VecEltTy,
isBigEndian) &&
CollectInsertionElements(I->getOperand(1), Shift, Elements, VecEltTy,
isBigEndian);
case Instruction::Shl: {
// Must be shifting by a constant that is a multiple of the element size.
ConstantInt *CI = dyn_cast<ConstantInt>(I->getOperand(1));
if (!CI) return false;
Shift += CI->getZExtValue();
if (!isMultipleOfTypeSize(Shift, VecEltTy)) return false;
return CollectInsertionElements(I->getOperand(0), Shift, Elements, VecEltTy,
isBigEndian);
}
}
}
/// OptimizeIntegerToVectorInsertions - If the input is an 'or' instruction, we
/// may be doing shifts and ors to assemble the elements of the vector manually.
/// Try to rip the code out and replace it with insertelements. This is to
/// optimize code like this:
///
/// %tmp37 = bitcast float %inc to i32
/// %tmp38 = zext i32 %tmp37 to i64
/// %tmp31 = bitcast float %inc5 to i32
/// %tmp32 = zext i32 %tmp31 to i64
/// %tmp33 = shl i64 %tmp32, 32
/// %ins35 = or i64 %tmp33, %tmp38
/// %tmp43 = bitcast i64 %ins35 to <2 x float>
///
/// Into two insertelements that do "buildvector{%inc, %inc5}".
static Value *OptimizeIntegerToVectorInsertions(BitCastInst &CI,
InstCombiner &IC) {
VectorType *DestVecTy = cast<VectorType>(CI.getType());
Value *IntInput = CI.getOperand(0);
SmallVector<Value*, 8> Elements(DestVecTy->getNumElements());
if (!CollectInsertionElements(IntInput, 0, Elements,
DestVecTy->getElementType(),
IC.getDataLayout().isBigEndian()))
return nullptr;
// If we succeeded, we know that all of the element are specified by Elements
// or are zero if Elements has a null entry. Recast this as a set of
// insertions.
Value *Result = Constant::getNullValue(CI.getType());
for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
if (!Elements[i]) continue; // Unset element.
Result = IC.Builder->CreateInsertElement(Result, Elements[i],
IC.Builder->getInt32(i));
}
return Result;
}
/// OptimizeIntToFloatBitCast - See if we can optimize an integer->float/double
/// bitcast. The various long double bitcasts can't get in here.
static Instruction *OptimizeIntToFloatBitCast(BitCastInst &CI, InstCombiner &IC,
const DataLayout &DL) {
Value *Src = CI.getOperand(0);
Type *DestTy = CI.getType();
// If this is a bitcast from int to float, check to see if the int is an
// extraction from a vector.
Value *VecInput = nullptr;
// bitcast(trunc(bitcast(somevector)))
if (match(Src, m_Trunc(m_BitCast(m_Value(VecInput)))) &&
isa<VectorType>(VecInput->getType())) {
VectorType *VecTy = cast<VectorType>(VecInput->getType());
unsigned DestWidth = DestTy->getPrimitiveSizeInBits();
if (VecTy->getPrimitiveSizeInBits() % DestWidth == 0) {
// If the element type of the vector doesn't match the result type,
// bitcast it to be a vector type we can extract from.
if (VecTy->getElementType() != DestTy) {
VecTy = VectorType::get(DestTy,
VecTy->getPrimitiveSizeInBits() / DestWidth);
VecInput = IC.Builder->CreateBitCast(VecInput, VecTy);
}
unsigned Elt = 0;
if (DL.isBigEndian())
Elt = VecTy->getPrimitiveSizeInBits() / DestWidth - 1;
return ExtractElementInst::Create(VecInput, IC.Builder->getInt32(Elt));
}
}
// bitcast(trunc(lshr(bitcast(somevector), cst))
ConstantInt *ShAmt = nullptr;
if (match(Src, m_Trunc(m_LShr(m_BitCast(m_Value(VecInput)),
m_ConstantInt(ShAmt)))) &&
isa<VectorType>(VecInput->getType())) {
VectorType *VecTy = cast<VectorType>(VecInput->getType());
unsigned DestWidth = DestTy->getPrimitiveSizeInBits();
if (VecTy->getPrimitiveSizeInBits() % DestWidth == 0 &&
ShAmt->getZExtValue() % DestWidth == 0) {
// If the element type of the vector doesn't match the result type,
// bitcast it to be a vector type we can extract from.
if (VecTy->getElementType() != DestTy) {
VecTy = VectorType::get(DestTy,
VecTy->getPrimitiveSizeInBits() / DestWidth);
VecInput = IC.Builder->CreateBitCast(VecInput, VecTy);
}
unsigned Elt = ShAmt->getZExtValue() / DestWidth;
if (DL.isBigEndian())
Elt = VecTy->getPrimitiveSizeInBits() / DestWidth - 1 - Elt;
return ExtractElementInst::Create(VecInput, IC.Builder->getInt32(Elt));
}
}
return nullptr;
}
Instruction *InstCombiner::visitBitCast(BitCastInst &CI) {
// If the operands are integer typed then apply the integer transforms,
// otherwise just apply the common ones.
Value *Src = CI.getOperand(0);
Type *SrcTy = Src->getType();
Type *DestTy = CI.getType();
// Get rid of casts from one type to the same type. These are useless and can
// be replaced by the operand.
if (DestTy == Src->getType())
return ReplaceInstUsesWith(CI, Src);
if (PointerType *DstPTy = dyn_cast<PointerType>(DestTy)) {
PointerType *SrcPTy = cast<PointerType>(SrcTy);
Type *DstElTy = DstPTy->getElementType();
Type *SrcElTy = SrcPTy->getElementType();
// If we are casting a alloca to a pointer to a type of the same
// size, rewrite the allocation instruction to allocate the "right" type.
// There is no need to modify malloc calls because it is their bitcast that
// needs to be cleaned up.
if (AllocaInst *AI = dyn_cast<AllocaInst>(Src))
if (Instruction *V = PromoteCastOfAllocation(CI, *AI))
return V;
// If the source and destination are pointers, and this cast is equivalent
// to a getelementptr X, 0, 0, 0... turn it into the appropriate gep.
// This can enhance SROA and other transforms that want type-safe pointers.
unsigned NumZeros = 0;
while (SrcElTy != DstElTy &&
isa<CompositeType>(SrcElTy) && !SrcElTy->isPointerTy() &&
SrcElTy->getNumContainedTypes() /* not "{}" */) {
SrcElTy = cast<CompositeType>(SrcElTy)->getTypeAtIndex(0U);
++NumZeros;
}
// If we found a path from the src to dest, create the getelementptr now.
if (SrcElTy == DstElTy) {
SmallVector<Value *, 8> Idxs(NumZeros + 1, Builder->getInt32(0));
return GetElementPtrInst::CreateInBounds(Src, Idxs);
}
}
// Try to optimize int -> float bitcasts.
if ((DestTy->isFloatTy() || DestTy->isDoubleTy()) && isa<IntegerType>(SrcTy))
if (Instruction *I = OptimizeIntToFloatBitCast(CI, *this, DL))
return I;
if (VectorType *DestVTy = dyn_cast<VectorType>(DestTy)) {
if (DestVTy->getNumElements() == 1 && !SrcTy->isVectorTy()) {
Value *Elem = Builder->CreateBitCast(Src, DestVTy->getElementType());
return InsertElementInst::Create(UndefValue::get(DestTy), Elem,
Constant::getNullValue(Type::getInt32Ty(CI.getContext())));
// FIXME: Canonicalize bitcast(insertelement) -> insertelement(bitcast)
}
if (isa<IntegerType>(SrcTy)) {
// If this is a cast from an integer to vector, check to see if the input
// is a trunc or zext of a bitcast from vector. If so, we can replace all
// the casts with a shuffle and (potentially) a bitcast.
if (isa<TruncInst>(Src) || isa<ZExtInst>(Src)) {
CastInst *SrcCast = cast<CastInst>(Src);
if (BitCastInst *BCIn = dyn_cast<BitCastInst>(SrcCast->getOperand(0)))
if (isa<VectorType>(BCIn->getOperand(0)->getType()))
if (Instruction *I = OptimizeVectorResize(BCIn->getOperand(0),
cast<VectorType>(DestTy), *this))
return I;
}
// If the input is an 'or' instruction, we may be doing shifts and ors to
// assemble the elements of the vector manually. Try to rip the code out
// and replace it with insertelements.
if (Value *V = OptimizeIntegerToVectorInsertions(CI, *this))
return ReplaceInstUsesWith(CI, V);
}
}
if (VectorType *SrcVTy = dyn_cast<VectorType>(SrcTy)) {
if (SrcVTy->getNumElements() == 1) {
// If our destination is not a vector, then make this a straight
// scalar-scalar cast.
if (!DestTy->isVectorTy()) {
Value *Elem =
Builder->CreateExtractElement(Src,
Constant::getNullValue(Type::getInt32Ty(CI.getContext())));
return CastInst::Create(Instruction::BitCast, Elem, DestTy);
}
// Otherwise, see if our source is an insert. If so, then use the scalar
// component directly.
if (InsertElementInst *IEI =
dyn_cast<InsertElementInst>(CI.getOperand(0)))
return CastInst::Create(Instruction::BitCast, IEI->getOperand(1),
DestTy);
}
}
if (ShuffleVectorInst *SVI = dyn_cast<ShuffleVectorInst>(Src)) {
// Okay, we have (bitcast (shuffle ..)). Check to see if this is
// a bitcast to a vector with the same # elts.
if (SVI->hasOneUse() && DestTy->isVectorTy() &&
DestTy->getVectorNumElements() == SVI->getType()->getNumElements() &&
SVI->getType()->getNumElements() ==
SVI->getOperand(0)->getType()->getVectorNumElements()) {
BitCastInst *Tmp;
// If either of the operands is a cast from CI.getType(), then
// evaluating the shuffle in the casted destination's type will allow
// us to eliminate at least one cast.
if (((Tmp = dyn_cast<BitCastInst>(SVI->getOperand(0))) &&
Tmp->getOperand(0)->getType() == DestTy) ||
((Tmp = dyn_cast<BitCastInst>(SVI->getOperand(1))) &&
Tmp->getOperand(0)->getType() == DestTy)) {
Value *LHS = Builder->CreateBitCast(SVI->getOperand(0), DestTy);
Value *RHS = Builder->CreateBitCast(SVI->getOperand(1), DestTy);
// Return a new shuffle vector. Use the same element ID's, as we
// know the vector types match #elts.
return new ShuffleVectorInst(LHS, RHS, SVI->getOperand(2));
}
}
}
if (SrcTy->isPointerTy())
return commonPointerCastTransforms(CI);
return commonCastTransforms(CI);
}
Instruction *InstCombiner::visitAddrSpaceCast(AddrSpaceCastInst &CI) {
// If the destination pointer element type is not the same as the source's
// first do a bitcast to the destination type, and then the addrspacecast.
// This allows the cast to be exposed to other transforms.
Value *Src = CI.getOperand(0);
PointerType *SrcTy = cast<PointerType>(Src->getType()->getScalarType());
PointerType *DestTy = cast<PointerType>(CI.getType()->getScalarType());
Type *DestElemTy = DestTy->getElementType();
if (SrcTy->getElementType() != DestElemTy) {
Type *MidTy = PointerType::get(DestElemTy, SrcTy->getAddressSpace());
if (VectorType *VT = dyn_cast<VectorType>(CI.getType())) {
// Handle vectors of pointers.
MidTy = VectorType::get(MidTy, VT->getNumElements());
}
Value *NewBitCast = Builder->CreateBitCast(Src, MidTy);
return new AddrSpaceCastInst(NewBitCast, CI.getType());
}
return commonPointerCastTransforms(CI);
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/InstCombineInternal.h | //===- InstCombineInternal.h - InstCombine pass internals -------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
/// \file
///
/// This file provides internal interfaces used to implement the InstCombine.
///
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_TRANSFORMS_INSTCOMBINE_INSTCOMBINEINTERNAL_H
#define LLVM_LIB_TRANSFORMS_INSTCOMBINE_INSTCOMBINEINTERNAL_H
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/TargetFolder.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InstVisitor.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Operator.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/Pass.h"
#include "llvm/Transforms/InstCombine/InstCombineWorklist.h"
#define DEBUG_TYPE "instcombine"
namespace llvm {
class CallSite;
class DataLayout;
class DominatorTree;
class TargetLibraryInfo;
class DbgDeclareInst;
class MemIntrinsic;
class MemSetInst;
/// \brief Assign a complexity or rank value to LLVM Values.
///
/// This routine maps IR values to various complexity ranks:
/// 0 -> undef
/// 1 -> Constants
/// 2 -> Other non-instructions
/// 3 -> Arguments
/// 3 -> Unary operations
/// 4 -> Other instructions
static inline unsigned getComplexity(Value *V) {
if (isa<Instruction>(V)) {
if (BinaryOperator::isNeg(V) || BinaryOperator::isFNeg(V) ||
BinaryOperator::isNot(V))
return 3;
return 4;
}
if (isa<Argument>(V))
return 3;
return isa<Constant>(V) ? (isa<UndefValue>(V) ? 0 : 1) : 2;
}
/// \brief Add one to a Constant
static inline Constant *AddOne(Constant *C) {
return ConstantExpr::getAdd(C, ConstantInt::get(C->getType(), 1));
}
/// \brief Subtract one from a Constant
static inline Constant *SubOne(Constant *C) {
return ConstantExpr::getSub(C, ConstantInt::get(C->getType(), 1));
}
/// \brief Return true if the specified value is free to invert (apply ~ to).
/// This happens in cases where the ~ can be eliminated. If WillInvertAllUses
/// is true, work under the assumption that the caller intends to remove all
/// uses of V and only keep uses of ~V.
///
static inline bool IsFreeToInvert(Value *V, bool WillInvertAllUses) {
// ~(~(X)) -> X.
if (BinaryOperator::isNot(V))
return true;
// Constants can be considered to be not'ed values.
if (isa<ConstantInt>(V))
return true;
// Compares can be inverted if all of their uses are being modified to use the
// ~V.
if (isa<CmpInst>(V))
return WillInvertAllUses;
// If `V` is of the form `A + Constant` then `-1 - V` can be folded into `(-1
// - Constant) - A` if we are willing to invert all of the uses.
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(V))
if (BO->getOpcode() == Instruction::Add ||
BO->getOpcode() == Instruction::Sub)
if (isa<Constant>(BO->getOperand(0)) || isa<Constant>(BO->getOperand(1)))
return WillInvertAllUses;
return false;
}
/// \brief Specific patterns of overflow check idioms that we match.
enum OverflowCheckFlavor {
OCF_UNSIGNED_ADD,
OCF_SIGNED_ADD,
OCF_UNSIGNED_SUB,
OCF_SIGNED_SUB,
OCF_UNSIGNED_MUL,
OCF_SIGNED_MUL,
OCF_INVALID
};
/// \brief Returns the OverflowCheckFlavor corresponding to a overflow_with_op
/// intrinsic.
static inline OverflowCheckFlavor
IntrinsicIDToOverflowCheckFlavor(unsigned ID) {
switch (ID) {
default:
return OCF_INVALID;
case Intrinsic::uadd_with_overflow:
return OCF_UNSIGNED_ADD;
case Intrinsic::sadd_with_overflow:
return OCF_SIGNED_ADD;
case Intrinsic::usub_with_overflow:
return OCF_UNSIGNED_SUB;
case Intrinsic::ssub_with_overflow:
return OCF_SIGNED_SUB;
case Intrinsic::umul_with_overflow:
return OCF_UNSIGNED_MUL;
case Intrinsic::smul_with_overflow:
return OCF_SIGNED_MUL;
}
}
/// \brief An IRBuilder inserter that adds new instructions to the instcombine
/// worklist.
class LLVM_LIBRARY_VISIBILITY InstCombineIRInserter
: public IRBuilderDefaultInserter<true> {
InstCombineWorklist &Worklist;
AssumptionCache *AC;
public:
InstCombineIRInserter(InstCombineWorklist &WL, AssumptionCache *AC)
: Worklist(WL), AC(AC) {}
void InsertHelper(Instruction *I, const Twine &Name, BasicBlock *BB,
BasicBlock::iterator InsertPt) const {
IRBuilderDefaultInserter<true>::InsertHelper(I, Name, BB, InsertPt);
Worklist.Add(I);
using namespace llvm::PatternMatch;
if (match(I, m_Intrinsic<Intrinsic::assume>()))
AC->registerAssumption(cast<CallInst>(I));
}
};
/// \brief The core instruction combiner logic.
///
/// This class provides both the logic to recursively visit instructions and
/// combine them, as well as the pass infrastructure for running this as part
/// of the LLVM pass pipeline.
class LLVM_LIBRARY_VISIBILITY InstCombiner
: public InstVisitor<InstCombiner, Instruction *> {
// FIXME: These members shouldn't be public.
public:
/// \brief A worklist of the instructions that need to be simplified.
InstCombineWorklist &Worklist;
/// \brief An IRBuilder that automatically inserts new instructions into the
/// worklist.
typedef IRBuilder<true, TargetFolder, InstCombineIRInserter> BuilderTy;
BuilderTy *Builder;
bool m_HLSLNoSinks = false; // HLSL Change
private:
// Mode in which we are running the combiner.
const bool MinimizeSize;
AliasAnalysis *AA;
// Required analyses.
// FIXME: These can never be null and should be references.
AssumptionCache *AC;
TargetLibraryInfo *TLI;
DominatorTree *DT;
const DataLayout &DL;
// Optional analyses. When non-null, these can both be used to do better
// combining and will be updated to reflect any changes.
LoopInfo *LI;
bool MadeIRChange;
public:
InstCombiner(InstCombineWorklist &Worklist, BuilderTy *Builder,
bool MinimizeSize, AliasAnalysis *AA,
AssumptionCache *AC, TargetLibraryInfo *TLI,
DominatorTree *DT, const DataLayout &DL, LoopInfo *LI)
: Worklist(Worklist), Builder(Builder), MinimizeSize(MinimizeSize),
AA(AA), AC(AC), TLI(TLI), DT(DT), DL(DL), LI(LI), MadeIRChange(false) {}
/// \brief Run the combiner over the entire worklist until it is empty.
///
/// \returns true if the IR is changed.
bool run();
AssumptionCache *getAssumptionCache() const { return AC; }
const DataLayout &getDataLayout() const { return DL; }
DominatorTree *getDominatorTree() const { return DT; }
LoopInfo *getLoopInfo() const { return LI; }
TargetLibraryInfo *getTargetLibraryInfo() const { return TLI; }
// Visitation implementation - Implement instruction combining for different
// instruction types. The semantics are as follows:
// Return Value:
// null - No change was made
// I - Change was made, I is still valid, I may be dead though
// otherwise - Change was made, replace I with returned instruction
//
Instruction *visitAdd(BinaryOperator &I);
Instruction *visitFAdd(BinaryOperator &I);
Value *OptimizePointerDifference(Value *LHS, Value *RHS, Type *Ty);
Instruction *visitSub(BinaryOperator &I);
Instruction *visitFSub(BinaryOperator &I);
Instruction *visitMul(BinaryOperator &I);
Value *foldFMulConst(Instruction *FMulOrDiv, Constant *C,
Instruction *InsertBefore);
Instruction *visitFMul(BinaryOperator &I);
Instruction *visitURem(BinaryOperator &I);
Instruction *visitSRem(BinaryOperator &I);
Instruction *visitFRem(BinaryOperator &I);
bool SimplifyDivRemOfSelect(BinaryOperator &I);
Instruction *commonRemTransforms(BinaryOperator &I);
Instruction *commonIRemTransforms(BinaryOperator &I);
Instruction *commonDivTransforms(BinaryOperator &I);
Instruction *commonIDivTransforms(BinaryOperator &I);
Instruction *visitUDiv(BinaryOperator &I);
Instruction *visitSDiv(BinaryOperator &I);
Instruction *visitFDiv(BinaryOperator &I);
Value *simplifyRangeCheck(ICmpInst *Cmp0, ICmpInst *Cmp1, bool Inverted);
Value *FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS);
Value *FoldAndOfFCmps(FCmpInst *LHS, FCmpInst *RHS);
Instruction *visitAnd(BinaryOperator &I);
Value *FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS, Instruction *CxtI);
Value *FoldOrOfFCmps(FCmpInst *LHS, FCmpInst *RHS);
Instruction *FoldOrWithConstants(BinaryOperator &I, Value *Op, Value *A,
Value *B, Value *C);
Instruction *FoldXorWithConstants(BinaryOperator &I, Value *Op, Value *A,
Value *B, Value *C);
Instruction *visitOr(BinaryOperator &I);
Instruction *visitXor(BinaryOperator &I);
Instruction *visitShl(BinaryOperator &I);
Instruction *visitAShr(BinaryOperator &I);
Instruction *visitLShr(BinaryOperator &I);
Instruction *commonShiftTransforms(BinaryOperator &I);
Instruction *FoldFCmp_IntToFP_Cst(FCmpInst &I, Instruction *LHSI,
Constant *RHSC);
Instruction *FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP,
GlobalVariable *GV, CmpInst &ICI,
ConstantInt *AndCst = nullptr);
Instruction *visitFCmpInst(FCmpInst &I);
Instruction *visitICmpInst(ICmpInst &I);
Instruction *visitICmpInstWithCastAndCast(ICmpInst &ICI);
Instruction *visitICmpInstWithInstAndIntCst(ICmpInst &ICI, Instruction *LHS,
ConstantInt *RHS);
Instruction *FoldICmpDivCst(ICmpInst &ICI, BinaryOperator *DivI,
ConstantInt *DivRHS);
Instruction *FoldICmpShrCst(ICmpInst &ICI, BinaryOperator *DivI,
ConstantInt *DivRHS);
Instruction *FoldICmpCstShrCst(ICmpInst &I, Value *Op, Value *A,
ConstantInt *CI1, ConstantInt *CI2);
Instruction *FoldICmpCstShlCst(ICmpInst &I, Value *Op, Value *A,
ConstantInt *CI1, ConstantInt *CI2);
Instruction *FoldICmpAddOpCst(Instruction &ICI, Value *X, ConstantInt *CI,
ICmpInst::Predicate Pred);
Instruction *FoldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
ICmpInst::Predicate Cond, Instruction &I);
Instruction *FoldShiftByConstant(Value *Op0, Constant *Op1,
BinaryOperator &I);
Instruction *commonCastTransforms(CastInst &CI);
Instruction *commonPointerCastTransforms(CastInst &CI);
Instruction *visitTrunc(TruncInst &CI);
Instruction *visitZExt(ZExtInst &CI);
Instruction *visitSExt(SExtInst &CI);
Instruction *visitFPTrunc(FPTruncInst &CI);
Instruction *visitFPExt(CastInst &CI);
Instruction *visitFPToUI(FPToUIInst &FI);
Instruction *visitFPToSI(FPToSIInst &FI);
Instruction *visitUIToFP(CastInst &CI);
Instruction *visitSIToFP(CastInst &CI);
Instruction *visitPtrToInt(PtrToIntInst &CI);
Instruction *visitIntToPtr(IntToPtrInst &CI);
Instruction *visitBitCast(BitCastInst &CI);
Instruction *visitAddrSpaceCast(AddrSpaceCastInst &CI);
Instruction *FoldSelectOpOp(SelectInst &SI, Instruction *TI, Instruction *FI);
Instruction *FoldSelectIntoOp(SelectInst &SI, Value *, Value *);
Instruction *FoldSPFofSPF(Instruction *Inner, SelectPatternFlavor SPF1,
Value *A, Value *B, Instruction &Outer,
SelectPatternFlavor SPF2, Value *C);
Instruction *FoldItoFPtoI(Instruction &FI);
Instruction *visitSelectInst(SelectInst &SI);
Instruction *visitSelectInstWithICmp(SelectInst &SI, ICmpInst *ICI);
Instruction *visitCallInst(CallInst &CI);
Instruction *visitInvokeInst(InvokeInst &II);
Instruction *SliceUpIllegalIntegerPHI(PHINode &PN);
Instruction *visitPHINode(PHINode &PN);
Instruction *visitGetElementPtrInst(GetElementPtrInst &GEP);
Instruction *visitAllocaInst(AllocaInst &AI);
Instruction *visitAllocSite(Instruction &FI);
Instruction *visitFree(CallInst &FI);
Instruction *visitLoadInst(LoadInst &LI);
Instruction *visitStoreInst(StoreInst &SI);
Instruction *visitBranchInst(BranchInst &BI);
Instruction *visitSwitchInst(SwitchInst &SI);
Instruction *visitReturnInst(ReturnInst &RI);
Instruction *visitInsertValueInst(InsertValueInst &IV);
Instruction *visitInsertElementInst(InsertElementInst &IE);
Instruction *visitExtractElementInst(ExtractElementInst &EI);
Instruction *visitShuffleVectorInst(ShuffleVectorInst &SVI);
Instruction *visitExtractValueInst(ExtractValueInst &EV);
Instruction *visitLandingPadInst(LandingPadInst &LI);
// visitInstruction - Specify what to return for unhandled instructions...
Instruction *visitInstruction(Instruction &I) { return nullptr; }
// True when DB dominates all uses of DI execpt UI.
// UI must be in the same block as DI.
// The routine checks that the DI parent and DB are different.
bool dominatesAllUses(const Instruction *DI, const Instruction *UI,
const BasicBlock *DB) const;
// Replace select with select operand SIOpd in SI-ICmp sequence when possible
bool replacedSelectWithOperand(SelectInst *SI, const ICmpInst *Icmp,
const unsigned SIOpd);
private:
bool ShouldChangeType(Type *From, Type *To) const;
Value *dyn_castNegVal(Value *V) const;
Value *dyn_castFNegVal(Value *V, bool NoSignedZero = false) const;
Type *FindElementAtOffset(PointerType *PtrTy, int64_t Offset,
SmallVectorImpl<Value *> &NewIndices);
Instruction *FoldOpIntoSelect(Instruction &Op, SelectInst *SI);
/// \brief Classify whether a cast is worth optimizing.
///
/// Returns true if the cast from "V to Ty" actually results in any code
/// being generated and is interesting to optimize out. If the cast can be
/// eliminated by some other simple transformation, we prefer to do the
/// simplification first.
bool ShouldOptimizeCast(Instruction::CastOps opcode, const Value *V,
Type *Ty);
/// \brief Try to optimize a sequence of instructions checking if an operation
/// on LHS and RHS overflows.
///
/// If a simplification is possible, stores the simplified result of the
/// operation in OperationResult and result of the overflow check in
/// OverflowResult, and return true. If no simplification is possible,
/// returns false.
bool OptimizeOverflowCheck(OverflowCheckFlavor OCF, Value *LHS, Value *RHS,
Instruction &CtxI, Value *&OperationResult,
Constant *&OverflowResult);
Instruction *visitCallSite(CallSite CS);
Instruction *tryOptimizeCall(CallInst *CI);
bool transformConstExprCastCall(CallSite CS);
Instruction *transformCallThroughTrampoline(CallSite CS,
IntrinsicInst *Tramp);
Instruction *transformZExtICmp(ICmpInst *ICI, Instruction &CI,
bool DoXform = true);
Instruction *transformSExtICmp(ICmpInst *ICI, Instruction &CI);
bool WillNotOverflowSignedAdd(Value *LHS, Value *RHS, Instruction &CxtI);
bool WillNotOverflowSignedSub(Value *LHS, Value *RHS, Instruction &CxtI);
bool WillNotOverflowUnsignedSub(Value *LHS, Value *RHS, Instruction &CxtI);
bool WillNotOverflowSignedMul(Value *LHS, Value *RHS, Instruction &CxtI);
Value *EmitGEPOffset(User *GEP);
Instruction *scalarizePHI(ExtractElementInst &EI, PHINode *PN);
Value *EvaluateInDifferentElementOrder(Value *V, ArrayRef<int> Mask);
public:
/// \brief Inserts an instruction \p New before instruction \p Old
///
/// Also adds the new instruction to the worklist and returns \p New so that
/// it is suitable for use as the return from the visitation patterns.
Instruction *InsertNewInstBefore(Instruction *New, Instruction &Old) {
assert(New && !New->getParent() &&
"New instruction already inserted into a basic block!");
BasicBlock *BB = Old.getParent();
BB->getInstList().insert(&Old, New); // Insert inst
Worklist.Add(New);
return New;
}
/// \brief Same as InsertNewInstBefore, but also sets the debug loc.
Instruction *InsertNewInstWith(Instruction *New, Instruction &Old) {
New->setDebugLoc(Old.getDebugLoc());
return InsertNewInstBefore(New, Old);
}
/// \brief A combiner-aware RAUW-like routine.
///
/// This method is to be used when an instruction is found to be dead,
/// replacable with another preexisting expression. Here we add all uses of
/// I to the worklist, replace all uses of I with the new value, then return
/// I, so that the inst combiner will know that I was modified.
Instruction *ReplaceInstUsesWith(Instruction &I, Value *V) {
// If there are no uses to replace, then we return nullptr to indicate that
// no changes were made to the program.
if (I.use_empty()) return nullptr;
Worklist.AddUsersToWorkList(I); // Add all modified instrs to worklist.
// If we are replacing the instruction with itself, this must be in a
// segment of unreachable code, so just clobber the instruction.
if (&I == V)
V = UndefValue::get(I.getType());
DEBUG(dbgs() << "IC: Replacing " << I << "\n"
<< " with " << *V << '\n');
I.replaceAllUsesWith(V);
return &I;
}
/// Creates a result tuple for an overflow intrinsic \p II with a given
/// \p Result and a constant \p Overflow value.
Instruction *CreateOverflowTuple(IntrinsicInst *II, Value *Result,
Constant *Overflow) {
Constant *V[] = {UndefValue::get(Result->getType()), Overflow};
StructType *ST = cast<StructType>(II->getType());
Constant *Struct = ConstantStruct::get(ST, V);
return InsertValueInst::Create(Struct, Result, 0);
}
/// \brief Combiner aware instruction erasure.
///
/// When dealing with an instruction that has side effects or produces a void
/// value, we can't rely on DCE to delete the instruction. Instead, visit
/// methods should return the value returned by this function.
Instruction *EraseInstFromFunction(Instruction &I) {
DEBUG(dbgs() << "IC: ERASE " << I << '\n');
assert(I.use_empty() && "Cannot erase instruction that is used!");
// Make sure that we reprocess all operands now that we reduced their
// use counts.
if (I.getNumOperands() < 8) {
for (User::op_iterator i = I.op_begin(), e = I.op_end(); i != e; ++i)
if (Instruction *Op = dyn_cast<Instruction>(*i))
Worklist.Add(Op);
}
Worklist.Remove(&I);
I.eraseFromParent();
MadeIRChange = true;
return nullptr; // Don't do anything with FI
}
void computeKnownBits(Value *V, APInt &KnownZero, APInt &KnownOne,
unsigned Depth, Instruction *CxtI) const {
return llvm::computeKnownBits(V, KnownZero, KnownOne, DL, Depth, AC, CxtI,
DT);
}
bool MaskedValueIsZero(Value *V, const APInt &Mask, unsigned Depth = 0,
Instruction *CxtI = nullptr) const {
return llvm::MaskedValueIsZero(V, Mask, DL, Depth, AC, CxtI, DT);
}
unsigned ComputeNumSignBits(Value *Op, unsigned Depth = 0,
Instruction *CxtI = nullptr) const {
return llvm::ComputeNumSignBits(Op, DL, Depth, AC, CxtI, DT);
}
void ComputeSignBit(Value *V, bool &KnownZero, bool &KnownOne,
unsigned Depth = 0, Instruction *CxtI = nullptr) const {
return llvm::ComputeSignBit(V, KnownZero, KnownOne, DL, Depth, AC, CxtI,
DT);
}
OverflowResult computeOverflowForUnsignedMul(Value *LHS, Value *RHS,
const Instruction *CxtI) {
return llvm::computeOverflowForUnsignedMul(LHS, RHS, DL, AC, CxtI, DT);
}
OverflowResult computeOverflowForUnsignedAdd(Value *LHS, Value *RHS,
const Instruction *CxtI) {
return llvm::computeOverflowForUnsignedAdd(LHS, RHS, DL, AC, CxtI, DT);
}
private:
/// \brief Performs a few simplifications for operators which are associative
/// or commutative.
bool SimplifyAssociativeOrCommutative(BinaryOperator &I);
/// \brief Tries to simplify binary operations which some other binary
/// operation distributes over.
///
/// It does this by either by factorizing out common terms (eg "(A*B)+(A*C)"
/// -> "A*(B+C)") or expanding out if this results in simplifications (eg: "A
/// & (B | C) -> (A&B) | (A&C)" if this is a win). Returns the simplified
/// value, or null if it didn't simplify.
Value *SimplifyUsingDistributiveLaws(BinaryOperator &I);
/// \brief Attempts to replace V with a simpler value based on the demanded
/// bits.
Value *SimplifyDemandedUseBits(Value *V, APInt DemandedMask, APInt &KnownZero,
APInt &KnownOne, unsigned Depth,
Instruction *CxtI);
bool SimplifyDemandedBits(Use &U, APInt DemandedMask, APInt &KnownZero,
APInt &KnownOne, unsigned Depth = 0);
/// Helper routine of SimplifyDemandedUseBits. It tries to simplify demanded
/// bit for "r1 = shr x, c1; r2 = shl r1, c2" instruction sequence.
Value *SimplifyShrShlDemandedBits(Instruction *Lsr, Instruction *Sftl,
APInt DemandedMask, APInt &KnownZero,
APInt &KnownOne);
/// \brief Tries to simplify operands to an integer instruction based on its
/// demanded bits.
bool SimplifyDemandedInstructionBits(Instruction &Inst);
Value *SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
APInt &UndefElts, unsigned Depth = 0);
Value *SimplifyVectorOp(BinaryOperator &Inst);
Value *SimplifyBSwap(BinaryOperator &Inst);
// FoldOpIntoPhi - Given a binary operator, cast instruction, or select
// which has a PHI node as operand #0, see if we can fold the instruction
// into the PHI (which is only possible if all operands to the PHI are
// constants).
//
Instruction *FoldOpIntoPhi(Instruction &I);
/// \brief Try to rotate an operation below a PHI node, using PHI nodes for
/// its operands.
Instruction *FoldPHIArgOpIntoPHI(PHINode &PN);
Instruction *FoldPHIArgBinOpIntoPHI(PHINode &PN);
Instruction *FoldPHIArgGEPIntoPHI(PHINode &PN);
Instruction *FoldPHIArgLoadIntoPHI(PHINode &PN);
Instruction *OptAndOp(Instruction *Op, ConstantInt *OpRHS,
ConstantInt *AndRHS, BinaryOperator &TheAnd);
Value *FoldLogicalPlusAnd(Value *LHS, Value *RHS, ConstantInt *Mask,
bool isSub, Instruction &I);
Value *InsertRangeTest(Value *V, Constant *Lo, Constant *Hi, bool isSigned,
bool Inside);
Instruction *PromoteCastOfAllocation(BitCastInst &CI, AllocaInst &AI);
Instruction *MatchBSwap(BinaryOperator &I);
bool SimplifyStoreAtEndOfBlock(StoreInst &SI);
Instruction *SimplifyMemTransfer(MemIntrinsic *MI);
Instruction *SimplifyMemSet(MemSetInst *MI);
Value *EvaluateInDifferentType(Value *V, Type *Ty, bool isSigned);
/// \brief Returns a value X such that Val = X * Scale, or null if none.
///
/// If the multiplication is known not to overflow then NoSignedWrap is set.
Value *Descale(Value *Val, APInt Scale, bool &NoSignedWrap);
};
} // end namespace llvm.
#undef DEBUG_TYPE
#endif
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/InstCombineCompares.cpp | //===- InstCombineCompares.cpp --------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the visitICmp and visitFCmp functions.
//
//===----------------------------------------------------------------------===//
#include "InstCombineInternal.h"
#include "llvm/ADT/APSInt.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/IR/ConstantRange.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
using namespace llvm;
using namespace PatternMatch;
#define DEBUG_TYPE "instcombine"
// How many times is a select replaced by one of its operands?
STATISTIC(NumSel, "Number of select opts");
// Initialization Routines
static ConstantInt *getOne(Constant *C) {
return ConstantInt::get(cast<IntegerType>(C->getType()), 1);
}
static ConstantInt *ExtractElement(Constant *V, Constant *Idx) {
return cast<ConstantInt>(ConstantExpr::getExtractElement(V, Idx));
}
static bool HasAddOverflow(ConstantInt *Result,
ConstantInt *In1, ConstantInt *In2,
bool IsSigned) {
if (!IsSigned)
return Result->getValue().ult(In1->getValue());
if (In2->isNegative())
return Result->getValue().sgt(In1->getValue());
return Result->getValue().slt(In1->getValue());
}
/// AddWithOverflow - Compute Result = In1+In2, returning true if the result
/// overflowed for this type.
static bool AddWithOverflow(Constant *&Result, Constant *In1,
Constant *In2, bool IsSigned = false) {
Result = ConstantExpr::getAdd(In1, In2);
if (VectorType *VTy = dyn_cast<VectorType>(In1->getType())) {
for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) {
Constant *Idx = ConstantInt::get(Type::getInt32Ty(In1->getContext()), i);
if (HasAddOverflow(ExtractElement(Result, Idx),
ExtractElement(In1, Idx),
ExtractElement(In2, Idx),
IsSigned))
return true;
}
return false;
}
return HasAddOverflow(cast<ConstantInt>(Result),
cast<ConstantInt>(In1), cast<ConstantInt>(In2),
IsSigned);
}
static bool HasSubOverflow(ConstantInt *Result,
ConstantInt *In1, ConstantInt *In2,
bool IsSigned) {
if (!IsSigned)
return Result->getValue().ugt(In1->getValue());
if (In2->isNegative())
return Result->getValue().slt(In1->getValue());
return Result->getValue().sgt(In1->getValue());
}
/// SubWithOverflow - Compute Result = In1-In2, returning true if the result
/// overflowed for this type.
static bool SubWithOverflow(Constant *&Result, Constant *In1,
Constant *In2, bool IsSigned = false) {
Result = ConstantExpr::getSub(In1, In2);
if (VectorType *VTy = dyn_cast<VectorType>(In1->getType())) {
for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) {
Constant *Idx = ConstantInt::get(Type::getInt32Ty(In1->getContext()), i);
if (HasSubOverflow(ExtractElement(Result, Idx),
ExtractElement(In1, Idx),
ExtractElement(In2, Idx),
IsSigned))
return true;
}
return false;
}
return HasSubOverflow(cast<ConstantInt>(Result),
cast<ConstantInt>(In1), cast<ConstantInt>(In2),
IsSigned);
}
/// isSignBitCheck - Given an exploded icmp instruction, return true if the
/// comparison only checks the sign bit. If it only checks the sign bit, set
/// TrueIfSigned if the result of the comparison is true when the input value is
/// signed.
static bool isSignBitCheck(ICmpInst::Predicate pred, ConstantInt *RHS,
bool &TrueIfSigned) {
switch (pred) {
case ICmpInst::ICMP_SLT: // True if LHS s< 0
TrueIfSigned = true;
return RHS->isZero();
case ICmpInst::ICMP_SLE: // True if LHS s<= RHS and RHS == -1
TrueIfSigned = true;
return RHS->isAllOnesValue();
case ICmpInst::ICMP_SGT: // True if LHS s> -1
TrueIfSigned = false;
return RHS->isAllOnesValue();
case ICmpInst::ICMP_UGT:
// True if LHS u> RHS and RHS == high-bit-mask - 1
TrueIfSigned = true;
return RHS->isMaxValue(true);
case ICmpInst::ICMP_UGE:
// True if LHS u>= RHS and RHS == high-bit-mask (2^7, 2^15, 2^31, etc)
TrueIfSigned = true;
return RHS->getValue().isSignBit();
default:
return false;
}
}
/// Returns true if the exploded icmp can be expressed as a signed comparison
/// to zero and updates the predicate accordingly.
/// The signedness of the comparison is preserved.
static bool isSignTest(ICmpInst::Predicate &pred, const ConstantInt *RHS) {
if (!ICmpInst::isSigned(pred))
return false;
if (RHS->isZero())
return ICmpInst::isRelational(pred);
if (RHS->isOne()) {
if (pred == ICmpInst::ICMP_SLT) {
pred = ICmpInst::ICMP_SLE;
return true;
}
} else if (RHS->isAllOnesValue()) {
if (pred == ICmpInst::ICMP_SGT) {
pred = ICmpInst::ICMP_SGE;
return true;
}
}
return false;
}
// isHighOnes - Return true if the constant is of the form 1+0+.
// This is the same as lowones(~X).
static bool isHighOnes(const ConstantInt *CI) {
return (~CI->getValue() + 1).isPowerOf2();
}
/// ComputeSignedMinMaxValuesFromKnownBits - Given a signed integer type and a
/// set of known zero and one bits, compute the maximum and minimum values that
/// could have the specified known zero and known one bits, returning them in
/// min/max.
static void ComputeSignedMinMaxValuesFromKnownBits(const APInt& KnownZero,
const APInt& KnownOne,
APInt& Min, APInt& Max) {
assert(KnownZero.getBitWidth() == KnownOne.getBitWidth() &&
KnownZero.getBitWidth() == Min.getBitWidth() &&
KnownZero.getBitWidth() == Max.getBitWidth() &&
"KnownZero, KnownOne and Min, Max must have equal bitwidth.");
APInt UnknownBits = ~(KnownZero|KnownOne);
// The minimum value is when all unknown bits are zeros, EXCEPT for the sign
// bit if it is unknown.
Min = KnownOne;
Max = KnownOne|UnknownBits;
if (UnknownBits.isNegative()) { // Sign bit is unknown
Min.setBit(Min.getBitWidth()-1);
Max.clearBit(Max.getBitWidth()-1);
}
}
// ComputeUnsignedMinMaxValuesFromKnownBits - Given an unsigned integer type and
// a set of known zero and one bits, compute the maximum and minimum values that
// could have the specified known zero and known one bits, returning them in
// min/max.
static void ComputeUnsignedMinMaxValuesFromKnownBits(const APInt &KnownZero,
const APInt &KnownOne,
APInt &Min, APInt &Max) {
assert(KnownZero.getBitWidth() == KnownOne.getBitWidth() &&
KnownZero.getBitWidth() == Min.getBitWidth() &&
KnownZero.getBitWidth() == Max.getBitWidth() &&
"Ty, KnownZero, KnownOne and Min, Max must have equal bitwidth.");
APInt UnknownBits = ~(KnownZero|KnownOne);
// The minimum value is when the unknown bits are all zeros.
Min = KnownOne;
// The maximum value is when the unknown bits are all ones.
Max = KnownOne|UnknownBits;
}
/// FoldCmpLoadFromIndexedGlobal - Called we see this pattern:
/// cmp pred (load (gep GV, ...)), cmpcst
/// where GV is a global variable with a constant initializer. Try to simplify
/// this into some simple computation that does not need the load. For example
/// we can optimize "icmp eq (load (gep "foo", 0, i)), 0" into "icmp eq i, 3".
///
/// If AndCst is non-null, then the loaded value is masked with that constant
/// before doing the comparison. This handles cases like "A[i]&4 == 0".
Instruction *InstCombiner::
FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP, GlobalVariable *GV,
CmpInst &ICI, ConstantInt *AndCst) {
Constant *Init = GV->getInitializer();
if (!isa<ConstantArray>(Init) && !isa<ConstantDataArray>(Init))
return nullptr;
uint64_t ArrayElementCount = Init->getType()->getArrayNumElements();
if (ArrayElementCount > 1024) return nullptr; // Don't blow up on huge arrays.
// There are many forms of this optimization we can handle, for now, just do
// the simple index into a single-dimensional array.
//
// Require: GEP GV, 0, i {{, constant indices}}
if (GEP->getNumOperands() < 3 ||
!isa<ConstantInt>(GEP->getOperand(1)) ||
!cast<ConstantInt>(GEP->getOperand(1))->isZero() ||
isa<Constant>(GEP->getOperand(2)))
return nullptr;
// Check that indices after the variable are constants and in-range for the
// type they index. Collect the indices. This is typically for arrays of
// structs.
SmallVector<unsigned, 4> LaterIndices;
Type *EltTy = Init->getType()->getArrayElementType();
for (unsigned i = 3, e = GEP->getNumOperands(); i != e; ++i) {
ConstantInt *Idx = dyn_cast<ConstantInt>(GEP->getOperand(i));
if (!Idx) return nullptr; // Variable index.
uint64_t IdxVal = Idx->getZExtValue();
if ((unsigned)IdxVal != IdxVal) return nullptr; // Too large array index.
if (StructType *STy = dyn_cast<StructType>(EltTy))
EltTy = STy->getElementType(IdxVal);
else if (ArrayType *ATy = dyn_cast<ArrayType>(EltTy)) {
if (IdxVal >= ATy->getNumElements()) return nullptr;
EltTy = ATy->getElementType();
} else {
return nullptr; // Unknown type.
}
LaterIndices.push_back(IdxVal);
}
enum { Overdefined = -3, Undefined = -2 };
// Variables for our state machines.
// FirstTrueElement/SecondTrueElement - Used to emit a comparison of the form
// "i == 47 | i == 87", where 47 is the first index the condition is true for,
// and 87 is the second (and last) index. FirstTrueElement is -2 when
// undefined, otherwise set to the first true element. SecondTrueElement is
// -2 when undefined, -3 when overdefined and >= 0 when that index is true.
int FirstTrueElement = Undefined, SecondTrueElement = Undefined;
// FirstFalseElement/SecondFalseElement - Used to emit a comparison of the
// form "i != 47 & i != 87". Same state transitions as for true elements.
int FirstFalseElement = Undefined, SecondFalseElement = Undefined;
/// TrueRangeEnd/FalseRangeEnd - In conjunction with First*Element, these
/// define a state machine that triggers for ranges of values that the index
/// is true or false for. This triggers on things like "abbbbc"[i] == 'b'.
/// This is -2 when undefined, -3 when overdefined, and otherwise the last
/// index in the range (inclusive). We use -2 for undefined here because we
/// use relative comparisons and don't want 0-1 to match -1.
int TrueRangeEnd = Undefined, FalseRangeEnd = Undefined;
// MagicBitvector - This is a magic bitvector where we set a bit if the
// comparison is true for element 'i'. If there are 64 elements or less in
// the array, this will fully represent all the comparison results.
uint64_t MagicBitvector = 0;
// Scan the array and see if one of our patterns matches.
Constant *CompareRHS = cast<Constant>(ICI.getOperand(1));
for (unsigned i = 0, e = ArrayElementCount; i != e; ++i) {
Constant *Elt = Init->getAggregateElement(i);
if (!Elt) return nullptr;
// If this is indexing an array of structures, get the structure element.
if (!LaterIndices.empty())
Elt = ConstantExpr::getExtractValue(Elt, LaterIndices);
// If the element is masked, handle it.
if (AndCst) Elt = ConstantExpr::getAnd(Elt, AndCst);
// Find out if the comparison would be true or false for the i'th element.
Constant *C = ConstantFoldCompareInstOperands(ICI.getPredicate(), Elt,
CompareRHS, DL, TLI);
// If the result is undef for this element, ignore it.
if (isa<UndefValue>(C)) {
// Extend range state machines to cover this element in case there is an
// undef in the middle of the range.
if (TrueRangeEnd == (int)i-1)
TrueRangeEnd = i;
if (FalseRangeEnd == (int)i-1)
FalseRangeEnd = i;
continue;
}
// If we can't compute the result for any of the elements, we have to give
// up evaluating the entire conditional.
if (!isa<ConstantInt>(C)) return nullptr;
// Otherwise, we know if the comparison is true or false for this element,
// update our state machines.
bool IsTrueForElt = !cast<ConstantInt>(C)->isZero();
// State machine for single/double/range index comparison.
if (IsTrueForElt) {
// Update the TrueElement state machine.
if (FirstTrueElement == Undefined)
FirstTrueElement = TrueRangeEnd = i; // First true element.
else {
// Update double-compare state machine.
if (SecondTrueElement == Undefined)
SecondTrueElement = i;
else
SecondTrueElement = Overdefined;
// Update range state machine.
if (TrueRangeEnd == (int)i-1)
TrueRangeEnd = i;
else
TrueRangeEnd = Overdefined;
}
} else {
// Update the FalseElement state machine.
if (FirstFalseElement == Undefined)
FirstFalseElement = FalseRangeEnd = i; // First false element.
else {
// Update double-compare state machine.
if (SecondFalseElement == Undefined)
SecondFalseElement = i;
else
SecondFalseElement = Overdefined;
// Update range state machine.
if (FalseRangeEnd == (int)i-1)
FalseRangeEnd = i;
else
FalseRangeEnd = Overdefined;
}
}
// If this element is in range, update our magic bitvector.
if (i < 64 && IsTrueForElt)
MagicBitvector |= 1ULL << i;
// If all of our states become overdefined, bail out early. Since the
// predicate is expensive, only check it every 8 elements. This is only
// really useful for really huge arrays.
if ((i & 8) == 0 && i >= 64 && SecondTrueElement == Overdefined &&
SecondFalseElement == Overdefined && TrueRangeEnd == Overdefined &&
FalseRangeEnd == Overdefined)
return nullptr;
}
// Now that we've scanned the entire array, emit our new comparison(s). We
// order the state machines in complexity of the generated code.
Value *Idx = GEP->getOperand(2);
// If the index is larger than the pointer size of the target, truncate the
// index down like the GEP would do implicitly. We don't have to do this for
// an inbounds GEP because the index can't be out of range.
if (!GEP->isInBounds()) {
Type *IntPtrTy = DL.getIntPtrType(GEP->getType());
unsigned PtrSize = IntPtrTy->getIntegerBitWidth();
if (Idx->getType()->getPrimitiveSizeInBits() > PtrSize)
Idx = Builder->CreateTrunc(Idx, IntPtrTy);
}
// If the comparison is only true for one or two elements, emit direct
// comparisons.
if (SecondTrueElement != Overdefined) {
// None true -> false.
if (FirstTrueElement == Undefined)
return ReplaceInstUsesWith(ICI, Builder->getFalse());
Value *FirstTrueIdx = ConstantInt::get(Idx->getType(), FirstTrueElement);
// True for one element -> 'i == 47'.
if (SecondTrueElement == Undefined)
return new ICmpInst(ICmpInst::ICMP_EQ, Idx, FirstTrueIdx);
// True for two elements -> 'i == 47 | i == 72'.
Value *C1 = Builder->CreateICmpEQ(Idx, FirstTrueIdx);
Value *SecondTrueIdx = ConstantInt::get(Idx->getType(), SecondTrueElement);
Value *C2 = Builder->CreateICmpEQ(Idx, SecondTrueIdx);
return BinaryOperator::CreateOr(C1, C2);
}
// If the comparison is only false for one or two elements, emit direct
// comparisons.
if (SecondFalseElement != Overdefined) {
// None false -> true.
if (FirstFalseElement == Undefined)
return ReplaceInstUsesWith(ICI, Builder->getTrue());
Value *FirstFalseIdx = ConstantInt::get(Idx->getType(), FirstFalseElement);
// False for one element -> 'i != 47'.
if (SecondFalseElement == Undefined)
return new ICmpInst(ICmpInst::ICMP_NE, Idx, FirstFalseIdx);
// False for two elements -> 'i != 47 & i != 72'.
Value *C1 = Builder->CreateICmpNE(Idx, FirstFalseIdx);
Value *SecondFalseIdx = ConstantInt::get(Idx->getType(),SecondFalseElement);
Value *C2 = Builder->CreateICmpNE(Idx, SecondFalseIdx);
return BinaryOperator::CreateAnd(C1, C2);
}
// If the comparison can be replaced with a range comparison for the elements
// where it is true, emit the range check.
if (TrueRangeEnd != Overdefined) {
assert(TrueRangeEnd != FirstTrueElement && "Should emit single compare");
// Generate (i-FirstTrue) <u (TrueRangeEnd-FirstTrue+1).
if (FirstTrueElement) {
Value *Offs = ConstantInt::get(Idx->getType(), -FirstTrueElement);
Idx = Builder->CreateAdd(Idx, Offs);
}
Value *End = ConstantInt::get(Idx->getType(),
TrueRangeEnd-FirstTrueElement+1);
return new ICmpInst(ICmpInst::ICMP_ULT, Idx, End);
}
// False range check.
if (FalseRangeEnd != Overdefined) {
assert(FalseRangeEnd != FirstFalseElement && "Should emit single compare");
// Generate (i-FirstFalse) >u (FalseRangeEnd-FirstFalse).
if (FirstFalseElement) {
Value *Offs = ConstantInt::get(Idx->getType(), -FirstFalseElement);
Idx = Builder->CreateAdd(Idx, Offs);
}
Value *End = ConstantInt::get(Idx->getType(),
FalseRangeEnd-FirstFalseElement);
return new ICmpInst(ICmpInst::ICMP_UGT, Idx, End);
}
// If a magic bitvector captures the entire comparison state
// of this load, replace it with computation that does:
// ((magic_cst >> i) & 1) != 0
{
Type *Ty = nullptr;
// Look for an appropriate type:
// - The type of Idx if the magic fits
// - The smallest fitting legal type if we have a DataLayout
// - Default to i32
if (ArrayElementCount <= Idx->getType()->getIntegerBitWidth())
Ty = Idx->getType();
// HLSL Change Begins: Don't introduce use of i64 here.
// TODO: Find a way to do this safely.
//else
// Ty = DL.getSmallestLegalIntType(Init->getContext(), ArrayElementCount);
// Use i32 if index type was i16 and too small, for instance
else if (ArrayElementCount <= 32)
Ty = Builder->getInt32Ty();
// HLSL Change Ends
if (Ty) {
Value *V = Builder->CreateIntCast(Idx, Ty, false);
V = Builder->CreateLShr(ConstantInt::get(Ty, MagicBitvector), V);
V = Builder->CreateAnd(ConstantInt::get(Ty, 1), V);
return new ICmpInst(ICmpInst::ICMP_NE, V, ConstantInt::get(Ty, 0));
}
// HLSL Change Begins: Generate 32-bit pattern for 64-bit case for now.
else if (ArrayElementCount <= 64) {
Ty = Builder->getInt32Ty();
Value *V = Builder->CreateIntCast(Idx, Ty, false);
Value *Cmp = Builder->CreateICmpULT(V, ConstantInt::get(Ty, 32));
Value *Sel = Builder->CreateSelect(Cmp,
ConstantInt::get(Ty, MagicBitvector & 0xFFFFFFFF),
ConstantInt::get(Ty, (MagicBitvector >> 32) & 0xFFFFFFFF));
Value *Shift = Builder->CreateAnd(V, ConstantInt::get(Ty, 0x1F));
V = Builder->CreateShl(ConstantInt::get(Ty, 0x1), Shift);
V = Builder->CreateAnd(Sel, V);
return new ICmpInst(ICmpInst::ICMP_NE, V, ConstantInt::get(Ty, 0));
}
// HLSL Change Ends
}
return nullptr;
}
/// EvaluateGEPOffsetExpression - Return a value that can be used to compare
/// the *offset* implied by a GEP to zero. For example, if we have &A[i], we
/// want to return 'i' for "icmp ne i, 0". Note that, in general, indices can
/// be complex, and scales are involved. The above expression would also be
/// legal to codegen as "icmp ne (i*4), 0" (assuming A is a pointer to i32).
/// This later form is less amenable to optimization though, and we are allowed
/// to generate the first by knowing that pointer arithmetic doesn't overflow.
///
/// If we can't emit an optimized form for this expression, this returns null.
///
static Value *EvaluateGEPOffsetExpression(User *GEP, InstCombiner &IC,
const DataLayout &DL) {
gep_type_iterator GTI = gep_type_begin(GEP);
// Check to see if this gep only has a single variable index. If so, and if
// any constant indices are a multiple of its scale, then we can compute this
// in terms of the scale of the variable index. For example, if the GEP
// implies an offset of "12 + i*4", then we can codegen this as "3 + i",
// because the expression will cross zero at the same point.
unsigned i, e = GEP->getNumOperands();
int64_t Offset = 0;
for (i = 1; i != e; ++i, ++GTI) {
if (ConstantInt *CI = dyn_cast<ConstantInt>(GEP->getOperand(i))) {
// Compute the aggregate offset of constant indices.
if (CI->isZero()) continue;
// Handle a struct index, which adds its field offset to the pointer.
if (StructType *STy = dyn_cast<StructType>(*GTI)) {
Offset += DL.getStructLayout(STy)->getElementOffset(CI->getZExtValue());
} else {
uint64_t Size = DL.getTypeAllocSize(GTI.getIndexedType());
Offset += Size*CI->getSExtValue();
}
} else {
// Found our variable index.
break;
}
}
// If there are no variable indices, we must have a constant offset, just
// evaluate it the general way.
if (i == e) return nullptr;
Value *VariableIdx = GEP->getOperand(i);
// Determine the scale factor of the variable element. For example, this is
// 4 if the variable index is into an array of i32.
uint64_t VariableScale = DL.getTypeAllocSize(GTI.getIndexedType());
// Verify that there are no other variable indices. If so, emit the hard way.
for (++i, ++GTI; i != e; ++i, ++GTI) {
ConstantInt *CI = dyn_cast<ConstantInt>(GEP->getOperand(i));
if (!CI) return nullptr;
// Compute the aggregate offset of constant indices.
if (CI->isZero()) continue;
// Handle a struct index, which adds its field offset to the pointer.
if (StructType *STy = dyn_cast<StructType>(*GTI)) {
Offset += DL.getStructLayout(STy)->getElementOffset(CI->getZExtValue());
} else {
uint64_t Size = DL.getTypeAllocSize(GTI.getIndexedType());
Offset += Size*CI->getSExtValue();
}
}
// Okay, we know we have a single variable index, which must be a
// pointer/array/vector index. If there is no offset, life is simple, return
// the index.
Type *IntPtrTy = DL.getIntPtrType(GEP->getOperand(0)->getType());
unsigned IntPtrWidth = IntPtrTy->getIntegerBitWidth();
if (Offset == 0) {
// Cast to intptrty in case a truncation occurs. If an extension is needed,
// we don't need to bother extending: the extension won't affect where the
// computation crosses zero.
if (VariableIdx->getType()->getPrimitiveSizeInBits() > IntPtrWidth) {
VariableIdx = IC.Builder->CreateTrunc(VariableIdx, IntPtrTy);
}
return VariableIdx;
}
// Otherwise, there is an index. The computation we will do will be modulo
// the pointer size, so get it.
uint64_t PtrSizeMask = ~0ULL >> (64-IntPtrWidth);
Offset &= PtrSizeMask;
VariableScale &= PtrSizeMask;
// To do this transformation, any constant index must be a multiple of the
// variable scale factor. For example, we can evaluate "12 + 4*i" as "3 + i",
// but we can't evaluate "10 + 3*i" in terms of i. Check that the offset is a
// multiple of the variable scale.
int64_t NewOffs = Offset / (int64_t)VariableScale;
if (Offset != NewOffs*(int64_t)VariableScale)
return nullptr;
// Okay, we can do this evaluation. Start by converting the index to intptr.
if (VariableIdx->getType() != IntPtrTy)
VariableIdx = IC.Builder->CreateIntCast(VariableIdx, IntPtrTy,
true /*Signed*/);
Constant *OffsetVal = ConstantInt::get(IntPtrTy, NewOffs);
return IC.Builder->CreateAdd(VariableIdx, OffsetVal, "offset");
}
/// FoldGEPICmp - Fold comparisons between a GEP instruction and something
/// else. At this point we know that the GEP is on the LHS of the comparison.
Instruction *InstCombiner::FoldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
ICmpInst::Predicate Cond,
Instruction &I) {
// Don't transform signed compares of GEPs into index compares. Even if the
// GEP is inbounds, the final add of the base pointer can have signed overflow
// and would change the result of the icmp.
// e.g. "&foo[0] <s &foo[1]" can't be folded to "true" because "foo" could be
// the maximum signed value for the pointer type.
if (ICmpInst::isSigned(Cond))
return nullptr;
// Look through bitcasts and addrspacecasts. We do not however want to remove
// 0 GEPs.
if (!isa<GetElementPtrInst>(RHS))
RHS = RHS->stripPointerCasts();
Value *PtrBase = GEPLHS->getOperand(0);
if (PtrBase == RHS && GEPLHS->isInBounds()) {
// ((gep Ptr, OFFSET) cmp Ptr) ---> (OFFSET cmp 0).
// This transformation (ignoring the base and scales) is valid because we
// know pointers can't overflow since the gep is inbounds. See if we can
// output an optimized form.
Value *Offset = EvaluateGEPOffsetExpression(GEPLHS, *this, DL);
// If not, synthesize the offset the hard way.
if (!Offset)
Offset = EmitGEPOffset(GEPLHS);
return new ICmpInst(ICmpInst::getSignedPredicate(Cond), Offset,
Constant::getNullValue(Offset->getType()));
} else if (GEPOperator *GEPRHS = dyn_cast<GEPOperator>(RHS)) {
// If the base pointers are different, but the indices are the same, just
// compare the base pointer.
if (PtrBase != GEPRHS->getOperand(0)) {
bool IndicesTheSame = GEPLHS->getNumOperands()==GEPRHS->getNumOperands();
IndicesTheSame &= GEPLHS->getOperand(0)->getType() ==
GEPRHS->getOperand(0)->getType();
if (IndicesTheSame)
for (unsigned i = 1, e = GEPLHS->getNumOperands(); i != e; ++i)
if (GEPLHS->getOperand(i) != GEPRHS->getOperand(i)) {
IndicesTheSame = false;
break;
}
// If all indices are the same, just compare the base pointers.
if (IndicesTheSame)
return new ICmpInst(Cond, GEPLHS->getOperand(0), GEPRHS->getOperand(0));
// If we're comparing GEPs with two base pointers that only differ in type
// and both GEPs have only constant indices or just one use, then fold
// the compare with the adjusted indices.
if (GEPLHS->isInBounds() && GEPRHS->isInBounds() &&
(GEPLHS->hasAllConstantIndices() || GEPLHS->hasOneUse()) &&
(GEPRHS->hasAllConstantIndices() || GEPRHS->hasOneUse()) &&
PtrBase->stripPointerCasts() ==
GEPRHS->getOperand(0)->stripPointerCasts()) {
Value *LOffset = EmitGEPOffset(GEPLHS);
Value *ROffset = EmitGEPOffset(GEPRHS);
// If we looked through an addrspacecast between different sized address
// spaces, the LHS and RHS pointers are different sized
// integers. Truncate to the smaller one.
Type *LHSIndexTy = LOffset->getType();
Type *RHSIndexTy = ROffset->getType();
if (LHSIndexTy != RHSIndexTy) {
if (LHSIndexTy->getPrimitiveSizeInBits() <
RHSIndexTy->getPrimitiveSizeInBits()) {
ROffset = Builder->CreateTrunc(ROffset, LHSIndexTy);
} else
LOffset = Builder->CreateTrunc(LOffset, RHSIndexTy);
}
Value *Cmp = Builder->CreateICmp(ICmpInst::getSignedPredicate(Cond),
LOffset, ROffset);
return ReplaceInstUsesWith(I, Cmp);
}
// Otherwise, the base pointers are different and the indices are
// different, bail out.
return nullptr;
}
// If one of the GEPs has all zero indices, recurse.
if (GEPLHS->hasAllZeroIndices())
return FoldGEPICmp(GEPRHS, GEPLHS->getOperand(0),
ICmpInst::getSwappedPredicate(Cond), I);
// If the other GEP has all zero indices, recurse.
if (GEPRHS->hasAllZeroIndices())
return FoldGEPICmp(GEPLHS, GEPRHS->getOperand(0), Cond, I);
bool GEPsInBounds = GEPLHS->isInBounds() && GEPRHS->isInBounds();
if (GEPLHS->getNumOperands() == GEPRHS->getNumOperands()) {
// If the GEPs only differ by one index, compare it.
unsigned NumDifferences = 0; // Keep track of # differences.
unsigned DiffOperand = 0; // The operand that differs.
for (unsigned i = 1, e = GEPRHS->getNumOperands(); i != e; ++i)
if (GEPLHS->getOperand(i) != GEPRHS->getOperand(i)) {
if (GEPLHS->getOperand(i)->getType()->getPrimitiveSizeInBits() !=
GEPRHS->getOperand(i)->getType()->getPrimitiveSizeInBits()) {
// Irreconcilable differences.
NumDifferences = 2;
break;
} else {
if (NumDifferences++) break;
DiffOperand = i;
}
}
if (NumDifferences == 0) // SAME GEP?
return ReplaceInstUsesWith(I, // No comparison is needed here.
Builder->getInt1(ICmpInst::isTrueWhenEqual(Cond)));
else if (NumDifferences == 1 && GEPsInBounds) {
Value *LHSV = GEPLHS->getOperand(DiffOperand);
Value *RHSV = GEPRHS->getOperand(DiffOperand);
// Make sure we do a signed comparison here.
return new ICmpInst(ICmpInst::getSignedPredicate(Cond), LHSV, RHSV);
}
}
// Only lower this if the icmp is the only user of the GEP or if we expect
// the result to fold to a constant!
if (GEPsInBounds && (isa<ConstantExpr>(GEPLHS) || GEPLHS->hasOneUse()) &&
(isa<ConstantExpr>(GEPRHS) || GEPRHS->hasOneUse())) {
// ((gep Ptr, OFFSET1) cmp (gep Ptr, OFFSET2) ---> (OFFSET1 cmp OFFSET2)
Value *L = EmitGEPOffset(GEPLHS);
Value *R = EmitGEPOffset(GEPRHS);
return new ICmpInst(ICmpInst::getSignedPredicate(Cond), L, R);
}
}
return nullptr;
}
/// FoldICmpAddOpCst - Fold "icmp pred (X+CI), X".
Instruction *InstCombiner::FoldICmpAddOpCst(Instruction &ICI,
Value *X, ConstantInt *CI,
ICmpInst::Predicate Pred) {
// From this point on, we know that (X+C <= X) --> (X+C < X) because C != 0,
// so the values can never be equal. Similarly for all other "or equals"
// operators.
// (X+1) <u X --> X >u (MAXUINT-1) --> X == 255
// (X+2) <u X --> X >u (MAXUINT-2) --> X > 253
// (X+MAXUINT) <u X --> X >u (MAXUINT-MAXUINT) --> X != 0
if (Pred == ICmpInst::ICMP_ULT || Pred == ICmpInst::ICMP_ULE) {
Value *R =
ConstantExpr::getSub(ConstantInt::getAllOnesValue(CI->getType()), CI);
return new ICmpInst(ICmpInst::ICMP_UGT, X, R);
}
// (X+1) >u X --> X <u (0-1) --> X != 255
// (X+2) >u X --> X <u (0-2) --> X <u 254
// (X+MAXUINT) >u X --> X <u (0-MAXUINT) --> X <u 1 --> X == 0
if (Pred == ICmpInst::ICMP_UGT || Pred == ICmpInst::ICMP_UGE)
return new ICmpInst(ICmpInst::ICMP_ULT, X, ConstantExpr::getNeg(CI));
unsigned BitWidth = CI->getType()->getPrimitiveSizeInBits();
ConstantInt *SMax = ConstantInt::get(X->getContext(),
APInt::getSignedMaxValue(BitWidth));
// (X+ 1) <s X --> X >s (MAXSINT-1) --> X == 127
// (X+ 2) <s X --> X >s (MAXSINT-2) --> X >s 125
// (X+MAXSINT) <s X --> X >s (MAXSINT-MAXSINT) --> X >s 0
// (X+MINSINT) <s X --> X >s (MAXSINT-MINSINT) --> X >s -1
// (X+ -2) <s X --> X >s (MAXSINT- -2) --> X >s 126
// (X+ -1) <s X --> X >s (MAXSINT- -1) --> X != 127
if (Pred == ICmpInst::ICMP_SLT || Pred == ICmpInst::ICMP_SLE)
return new ICmpInst(ICmpInst::ICMP_SGT, X, ConstantExpr::getSub(SMax, CI));
// (X+ 1) >s X --> X <s (MAXSINT-(1-1)) --> X != 127
// (X+ 2) >s X --> X <s (MAXSINT-(2-1)) --> X <s 126
// (X+MAXSINT) >s X --> X <s (MAXSINT-(MAXSINT-1)) --> X <s 1
// (X+MINSINT) >s X --> X <s (MAXSINT-(MINSINT-1)) --> X <s -2
// (X+ -2) >s X --> X <s (MAXSINT-(-2-1)) --> X <s -126
// (X+ -1) >s X --> X <s (MAXSINT-(-1-1)) --> X == -128
assert(Pred == ICmpInst::ICMP_SGT || Pred == ICmpInst::ICMP_SGE);
Constant *C = Builder->getInt(CI->getValue()-1);
return new ICmpInst(ICmpInst::ICMP_SLT, X, ConstantExpr::getSub(SMax, C));
}
/// FoldICmpDivCst - Fold "icmp pred, ([su]div X, DivRHS), CmpRHS" where DivRHS
/// and CmpRHS are both known to be integer constants.
Instruction *InstCombiner::FoldICmpDivCst(ICmpInst &ICI, BinaryOperator *DivI,
ConstantInt *DivRHS) {
ConstantInt *CmpRHS = cast<ConstantInt>(ICI.getOperand(1));
const APInt &CmpRHSV = CmpRHS->getValue();
// FIXME: If the operand types don't match the type of the divide
// then don't attempt this transform. The code below doesn't have the
// logic to deal with a signed divide and an unsigned compare (and
// vice versa). This is because (x /s C1) <s C2 produces different
// results than (x /s C1) <u C2 or (x /u C1) <s C2 or even
// (x /u C1) <u C2. Simply casting the operands and result won't
// work. :( The if statement below tests that condition and bails
// if it finds it.
bool DivIsSigned = DivI->getOpcode() == Instruction::SDiv;
if (!ICI.isEquality() && DivIsSigned != ICI.isSigned())
return nullptr;
if (DivRHS->isZero())
return nullptr; // The ProdOV computation fails on divide by zero.
if (DivIsSigned && DivRHS->isAllOnesValue())
return nullptr; // The overflow computation also screws up here
if (DivRHS->isOne()) {
// This eliminates some funny cases with INT_MIN.
ICI.setOperand(0, DivI->getOperand(0)); // X/1 == X.
return &ICI;
}
// Compute Prod = CI * DivRHS. We are essentially solving an equation
// of form X/C1=C2. We solve for X by multiplying C1 (DivRHS) and
// C2 (CI). By solving for X we can turn this into a range check
// instead of computing a divide.
Constant *Prod = ConstantExpr::getMul(CmpRHS, DivRHS);
// Determine if the product overflows by seeing if the product is
// not equal to the divide. Make sure we do the same kind of divide
// as in the LHS instruction that we're folding.
bool ProdOV = (DivIsSigned ? ConstantExpr::getSDiv(Prod, DivRHS) :
ConstantExpr::getUDiv(Prod, DivRHS)) != CmpRHS;
// Get the ICmp opcode
ICmpInst::Predicate Pred = ICI.getPredicate();
/// If the division is known to be exact, then there is no remainder from the
/// divide, so the covered range size is unit, otherwise it is the divisor.
ConstantInt *RangeSize = DivI->isExact() ? getOne(Prod) : DivRHS;
// Figure out the interval that is being checked. For example, a comparison
// like "X /u 5 == 0" is really checking that X is in the interval [0, 5).
// Compute this interval based on the constants involved and the signedness of
// the compare/divide. This computes a half-open interval, keeping track of
// whether either value in the interval overflows. After analysis each
// overflow variable is set to 0 if it's corresponding bound variable is valid
// -1 if overflowed off the bottom end, or +1 if overflowed off the top end.
int LoOverflow = 0, HiOverflow = 0;
Constant *LoBound = nullptr, *HiBound = nullptr;
if (!DivIsSigned) { // udiv
// e.g. X/5 op 3 --> [15, 20)
LoBound = Prod;
HiOverflow = LoOverflow = ProdOV;
if (!HiOverflow) {
// If this is not an exact divide, then many values in the range collapse
// to the same result value.
HiOverflow = AddWithOverflow(HiBound, LoBound, RangeSize, false);
}
} else if (DivRHS->getValue().isStrictlyPositive()) { // Divisor is > 0.
if (CmpRHSV == 0) { // (X / pos) op 0
// Can't overflow. e.g. X/2 op 0 --> [-1, 2)
LoBound = ConstantExpr::getNeg(SubOne(RangeSize));
HiBound = RangeSize;
} else if (CmpRHSV.isStrictlyPositive()) { // (X / pos) op pos
LoBound = Prod; // e.g. X/5 op 3 --> [15, 20)
HiOverflow = LoOverflow = ProdOV;
if (!HiOverflow)
HiOverflow = AddWithOverflow(HiBound, Prod, RangeSize, true);
} else { // (X / pos) op neg
// e.g. X/5 op -3 --> [-15-4, -15+1) --> [-19, -14)
HiBound = AddOne(Prod);
LoOverflow = HiOverflow = ProdOV ? -1 : 0;
if (!LoOverflow) {
ConstantInt *DivNeg =cast<ConstantInt>(ConstantExpr::getNeg(RangeSize));
LoOverflow = AddWithOverflow(LoBound, HiBound, DivNeg, true) ? -1 : 0;
}
}
} else if (DivRHS->isNegative()) { // Divisor is < 0.
if (DivI->isExact())
RangeSize = cast<ConstantInt>(ConstantExpr::getNeg(RangeSize));
if (CmpRHSV == 0) { // (X / neg) op 0
// e.g. X/-5 op 0 --> [-4, 5)
LoBound = AddOne(RangeSize);
HiBound = cast<ConstantInt>(ConstantExpr::getNeg(RangeSize));
if (HiBound == DivRHS) { // -INTMIN = INTMIN
HiOverflow = 1; // [INTMIN+1, overflow)
HiBound = nullptr; // e.g. X/INTMIN = 0 --> X > INTMIN
}
} else if (CmpRHSV.isStrictlyPositive()) { // (X / neg) op pos
// e.g. X/-5 op 3 --> [-19, -14)
HiBound = AddOne(Prod);
HiOverflow = LoOverflow = ProdOV ? -1 : 0;
if (!LoOverflow)
LoOverflow = AddWithOverflow(LoBound, HiBound, RangeSize, true) ? -1:0;
} else { // (X / neg) op neg
LoBound = Prod; // e.g. X/-5 op -3 --> [15, 20)
LoOverflow = HiOverflow = ProdOV;
if (!HiOverflow)
HiOverflow = SubWithOverflow(HiBound, Prod, RangeSize, true);
}
// Dividing by a negative swaps the condition. LT <-> GT
Pred = ICmpInst::getSwappedPredicate(Pred);
}
Value *X = DivI->getOperand(0);
switch (Pred) {
default: llvm_unreachable("Unhandled icmp opcode!");
case ICmpInst::ICMP_EQ:
if (LoOverflow && HiOverflow)
return ReplaceInstUsesWith(ICI, Builder->getFalse());
if (HiOverflow)
return new ICmpInst(DivIsSigned ? ICmpInst::ICMP_SGE :
ICmpInst::ICMP_UGE, X, LoBound);
if (LoOverflow)
return new ICmpInst(DivIsSigned ? ICmpInst::ICMP_SLT :
ICmpInst::ICMP_ULT, X, HiBound);
return ReplaceInstUsesWith(ICI, InsertRangeTest(X, LoBound, HiBound,
DivIsSigned, true));
case ICmpInst::ICMP_NE:
if (LoOverflow && HiOverflow)
return ReplaceInstUsesWith(ICI, Builder->getTrue());
if (HiOverflow)
return new ICmpInst(DivIsSigned ? ICmpInst::ICMP_SLT :
ICmpInst::ICMP_ULT, X, LoBound);
if (LoOverflow)
return new ICmpInst(DivIsSigned ? ICmpInst::ICMP_SGE :
ICmpInst::ICMP_UGE, X, HiBound);
return ReplaceInstUsesWith(ICI, InsertRangeTest(X, LoBound, HiBound,
DivIsSigned, false));
case ICmpInst::ICMP_ULT:
case ICmpInst::ICMP_SLT:
if (LoOverflow == +1) // Low bound is greater than input range.
return ReplaceInstUsesWith(ICI, Builder->getTrue());
if (LoOverflow == -1) // Low bound is less than input range.
return ReplaceInstUsesWith(ICI, Builder->getFalse());
return new ICmpInst(Pred, X, LoBound);
case ICmpInst::ICMP_UGT:
case ICmpInst::ICMP_SGT:
if (HiOverflow == +1) // High bound greater than input range.
return ReplaceInstUsesWith(ICI, Builder->getFalse());
if (HiOverflow == -1) // High bound less than input range.
return ReplaceInstUsesWith(ICI, Builder->getTrue());
if (Pred == ICmpInst::ICMP_UGT)
return new ICmpInst(ICmpInst::ICMP_UGE, X, HiBound);
return new ICmpInst(ICmpInst::ICMP_SGE, X, HiBound);
}
}
/// FoldICmpShrCst - Handle "icmp(([al]shr X, cst1), cst2)".
Instruction *InstCombiner::FoldICmpShrCst(ICmpInst &ICI, BinaryOperator *Shr,
ConstantInt *ShAmt) {
const APInt &CmpRHSV = cast<ConstantInt>(ICI.getOperand(1))->getValue();
// Check that the shift amount is in range. If not, don't perform
// undefined shifts. When the shift is visited it will be
// simplified.
uint32_t TypeBits = CmpRHSV.getBitWidth();
uint32_t ShAmtVal = (uint32_t)ShAmt->getLimitedValue(TypeBits);
if (ShAmtVal >= TypeBits || ShAmtVal == 0)
return nullptr;
if (!ICI.isEquality()) {
// If we have an unsigned comparison and an ashr, we can't simplify this.
// Similarly for signed comparisons with lshr.
if (ICI.isSigned() != (Shr->getOpcode() == Instruction::AShr))
return nullptr;
// Otherwise, all lshr and most exact ashr's are equivalent to a udiv/sdiv
// by a power of 2. Since we already have logic to simplify these,
// transform to div and then simplify the resultant comparison.
if (Shr->getOpcode() == Instruction::AShr &&
(!Shr->isExact() || ShAmtVal == TypeBits - 1))
return nullptr;
// Revisit the shift (to delete it).
Worklist.Add(Shr);
Constant *DivCst =
ConstantInt::get(Shr->getType(), APInt::getOneBitSet(TypeBits, ShAmtVal));
Value *Tmp =
Shr->getOpcode() == Instruction::AShr ?
Builder->CreateSDiv(Shr->getOperand(0), DivCst, "", Shr->isExact()) :
Builder->CreateUDiv(Shr->getOperand(0), DivCst, "", Shr->isExact());
ICI.setOperand(0, Tmp);
// If the builder folded the binop, just return it.
BinaryOperator *TheDiv = dyn_cast<BinaryOperator>(Tmp);
if (!TheDiv)
return &ICI;
// Otherwise, fold this div/compare.
assert(TheDiv->getOpcode() == Instruction::SDiv ||
TheDiv->getOpcode() == Instruction::UDiv);
Instruction *Res = FoldICmpDivCst(ICI, TheDiv, cast<ConstantInt>(DivCst));
assert(Res && "This div/cst should have folded!");
return Res;
}
// If we are comparing against bits always shifted out, the
// comparison cannot succeed.
APInt Comp = CmpRHSV << ShAmtVal;
ConstantInt *ShiftedCmpRHS = Builder->getInt(Comp);
if (Shr->getOpcode() == Instruction::LShr)
Comp = Comp.lshr(ShAmtVal);
else
Comp = Comp.ashr(ShAmtVal);
if (Comp != CmpRHSV) { // Comparing against a bit that we know is zero.
bool IsICMP_NE = ICI.getPredicate() == ICmpInst::ICMP_NE;
Constant *Cst = Builder->getInt1(IsICMP_NE);
return ReplaceInstUsesWith(ICI, Cst);
}
// Otherwise, check to see if the bits shifted out are known to be zero.
// If so, we can compare against the unshifted value:
// (X & 4) >> 1 == 2 --> (X & 4) == 4.
if (Shr->hasOneUse() && Shr->isExact())
return new ICmpInst(ICI.getPredicate(), Shr->getOperand(0), ShiftedCmpRHS);
if (Shr->hasOneUse()) {
// Otherwise strength reduce the shift into an and.
APInt Val(APInt::getHighBitsSet(TypeBits, TypeBits - ShAmtVal));
Constant *Mask = Builder->getInt(Val);
Value *And = Builder->CreateAnd(Shr->getOperand(0),
Mask, Shr->getName()+".mask");
return new ICmpInst(ICI.getPredicate(), And, ShiftedCmpRHS);
}
return nullptr;
}
/// FoldICmpCstShrCst - Handle "(icmp eq/ne (ashr/lshr const2, A), const1)" ->
/// (icmp eq/ne A, Log2(const2/const1)) ->
/// (icmp eq/ne A, Log2(const2) - Log2(const1)).
Instruction *InstCombiner::FoldICmpCstShrCst(ICmpInst &I, Value *Op, Value *A,
ConstantInt *CI1,
ConstantInt *CI2) {
assert(I.isEquality() && "Cannot fold icmp gt/lt");
auto getConstant = [&I, this](bool IsTrue) {
if (I.getPredicate() == I.ICMP_NE)
IsTrue = !IsTrue;
return ReplaceInstUsesWith(I, ConstantInt::get(I.getType(), IsTrue));
};
auto getICmp = [&I](CmpInst::Predicate Pred, Value *LHS, Value *RHS) {
if (I.getPredicate() == I.ICMP_NE)
Pred = CmpInst::getInversePredicate(Pred);
return new ICmpInst(Pred, LHS, RHS);
};
APInt AP1 = CI1->getValue();
APInt AP2 = CI2->getValue();
// Don't bother doing any work for cases which InstSimplify handles.
if (AP2 == 0)
return nullptr;
bool IsAShr = isa<AShrOperator>(Op);
if (IsAShr) {
if (AP2.isAllOnesValue())
return nullptr;
if (AP2.isNegative() != AP1.isNegative())
return nullptr;
if (AP2.sgt(AP1))
return nullptr;
}
if (!AP1)
// 'A' must be large enough to shift out the highest set bit.
return getICmp(I.ICMP_UGT, A,
ConstantInt::get(A->getType(), AP2.logBase2()));
if (AP1 == AP2)
return getICmp(I.ICMP_EQ, A, ConstantInt::getNullValue(A->getType()));
// Get the distance between the highest bit that's set.
int Shift;
// Both the constants are negative, take their positive to calculate log.
if (IsAShr && AP1.isNegative())
// Get the ones' complement of AP2 and AP1 when computing the distance.
Shift = (~AP2).logBase2() - (~AP1).logBase2();
else
Shift = AP2.logBase2() - AP1.logBase2();
if (Shift > 0) {
if (IsAShr ? AP1 == AP2.ashr(Shift) : AP1 == AP2.lshr(Shift))
return getICmp(I.ICMP_EQ, A, ConstantInt::get(A->getType(), Shift));
}
// Shifting const2 will never be equal to const1.
return getConstant(false);
}
/// FoldICmpCstShlCst - Handle "(icmp eq/ne (shl const2, A), const1)" ->
/// (icmp eq/ne A, TrailingZeros(const1) - TrailingZeros(const2)).
Instruction *InstCombiner::FoldICmpCstShlCst(ICmpInst &I, Value *Op, Value *A,
ConstantInt *CI1,
ConstantInt *CI2) {
assert(I.isEquality() && "Cannot fold icmp gt/lt");
auto getConstant = [&I, this](bool IsTrue) {
if (I.getPredicate() == I.ICMP_NE)
IsTrue = !IsTrue;
return ReplaceInstUsesWith(I, ConstantInt::get(I.getType(), IsTrue));
};
auto getICmp = [&I](CmpInst::Predicate Pred, Value *LHS, Value *RHS) {
if (I.getPredicate() == I.ICMP_NE)
Pred = CmpInst::getInversePredicate(Pred);
return new ICmpInst(Pred, LHS, RHS);
};
APInt AP1 = CI1->getValue();
APInt AP2 = CI2->getValue();
// Don't bother doing any work for cases which InstSimplify handles.
if (AP2 == 0)
return nullptr;
unsigned AP2TrailingZeros = AP2.countTrailingZeros();
if (!AP1 && AP2TrailingZeros != 0)
return getICmp(I.ICMP_UGE, A,
ConstantInt::get(A->getType(), AP2.getBitWidth() - AP2TrailingZeros));
if (AP1 == AP2)
return getICmp(I.ICMP_EQ, A, ConstantInt::getNullValue(A->getType()));
// Get the distance between the lowest bits that are set.
int Shift = AP1.countTrailingZeros() - AP2TrailingZeros;
if (Shift > 0 && AP2.shl(Shift) == AP1)
return getICmp(I.ICMP_EQ, A, ConstantInt::get(A->getType(), Shift));
// Shifting const2 will never be equal to const1.
return getConstant(false);
}
/// visitICmpInstWithInstAndIntCst - Handle "icmp (instr, intcst)".
///
Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
Instruction *LHSI,
ConstantInt *RHS) {
const APInt &RHSV = RHS->getValue();
switch (LHSI->getOpcode()) {
case Instruction::Trunc:
if (ICI.isEquality() && LHSI->hasOneUse()) {
// Simplify icmp eq (trunc x to i8), 42 -> icmp eq x, 42|highbits if all
// of the high bits truncated out of x are known.
unsigned DstBits = LHSI->getType()->getPrimitiveSizeInBits(),
SrcBits = LHSI->getOperand(0)->getType()->getPrimitiveSizeInBits();
APInt KnownZero(SrcBits, 0), KnownOne(SrcBits, 0);
computeKnownBits(LHSI->getOperand(0), KnownZero, KnownOne, 0, &ICI);
// If all the high bits are known, we can do this xform.
if ((KnownZero|KnownOne).countLeadingOnes() >= SrcBits-DstBits) {
// Pull in the high bits from known-ones set.
APInt NewRHS = RHS->getValue().zext(SrcBits);
NewRHS |= KnownOne & APInt::getHighBitsSet(SrcBits, SrcBits-DstBits);
return new ICmpInst(ICI.getPredicate(), LHSI->getOperand(0),
Builder->getInt(NewRHS));
}
}
break;
case Instruction::Xor: // (icmp pred (xor X, XorCst), CI)
if (ConstantInt *XorCst = dyn_cast<ConstantInt>(LHSI->getOperand(1))) {
// If this is a comparison that tests the signbit (X < 0) or (x > -1),
// fold the xor.
if ((ICI.getPredicate() == ICmpInst::ICMP_SLT && RHSV == 0) ||
(ICI.getPredicate() == ICmpInst::ICMP_SGT && RHSV.isAllOnesValue())) {
Value *CompareVal = LHSI->getOperand(0);
// If the sign bit of the XorCst is not set, there is no change to
// the operation, just stop using the Xor.
if (!XorCst->isNegative()) {
ICI.setOperand(0, CompareVal);
Worklist.Add(LHSI);
return &ICI;
}
// Was the old condition true if the operand is positive?
bool isTrueIfPositive = ICI.getPredicate() == ICmpInst::ICMP_SGT;
// If so, the new one isn't.
isTrueIfPositive ^= true;
if (isTrueIfPositive)
return new ICmpInst(ICmpInst::ICMP_SGT, CompareVal,
SubOne(RHS));
else
return new ICmpInst(ICmpInst::ICMP_SLT, CompareVal,
AddOne(RHS));
}
if (LHSI->hasOneUse()) {
// (icmp u/s (xor A SignBit), C) -> (icmp s/u A, (xor C SignBit))
if (!ICI.isEquality() && XorCst->getValue().isSignBit()) {
const APInt &SignBit = XorCst->getValue();
ICmpInst::Predicate Pred = ICI.isSigned()
? ICI.getUnsignedPredicate()
: ICI.getSignedPredicate();
return new ICmpInst(Pred, LHSI->getOperand(0),
Builder->getInt(RHSV ^ SignBit));
}
// (icmp u/s (xor A ~SignBit), C) -> (icmp s/u (xor C ~SignBit), A)
if (!ICI.isEquality() && XorCst->isMaxValue(true)) {
const APInt &NotSignBit = XorCst->getValue();
ICmpInst::Predicate Pred = ICI.isSigned()
? ICI.getUnsignedPredicate()
: ICI.getSignedPredicate();
Pred = ICI.getSwappedPredicate(Pred);
return new ICmpInst(Pred, LHSI->getOperand(0),
Builder->getInt(RHSV ^ NotSignBit));
}
}
// (icmp ugt (xor X, C), ~C) -> (icmp ult X, C)
// iff -C is a power of 2
if (ICI.getPredicate() == ICmpInst::ICMP_UGT &&
XorCst->getValue() == ~RHSV && (RHSV + 1).isPowerOf2())
return new ICmpInst(ICmpInst::ICMP_ULT, LHSI->getOperand(0), XorCst);
// (icmp ult (xor X, C), -C) -> (icmp uge X, C)
// iff -C is a power of 2
if (ICI.getPredicate() == ICmpInst::ICMP_ULT &&
XorCst->getValue() == -RHSV && RHSV.isPowerOf2())
return new ICmpInst(ICmpInst::ICMP_UGE, LHSI->getOperand(0), XorCst);
}
break;
case Instruction::And: // (icmp pred (and X, AndCst), RHS)
if (LHSI->hasOneUse() && isa<ConstantInt>(LHSI->getOperand(1)) &&
LHSI->getOperand(0)->hasOneUse()) {
ConstantInt *AndCst = cast<ConstantInt>(LHSI->getOperand(1));
// If the LHS is an AND of a truncating cast, we can widen the
// and/compare to be the input width without changing the value
// produced, eliminating a cast.
if (TruncInst *Cast = dyn_cast<TruncInst>(LHSI->getOperand(0))) {
// We can do this transformation if either the AND constant does not
// have its sign bit set or if it is an equality comparison.
// Extending a relational comparison when we're checking the sign
// bit would not work.
if (ICI.isEquality() ||
(!AndCst->isNegative() && RHSV.isNonNegative())) {
Value *NewAnd =
Builder->CreateAnd(Cast->getOperand(0),
ConstantExpr::getZExt(AndCst, Cast->getSrcTy()));
NewAnd->takeName(LHSI);
return new ICmpInst(ICI.getPredicate(), NewAnd,
ConstantExpr::getZExt(RHS, Cast->getSrcTy()));
}
}
// If the LHS is an AND of a zext, and we have an equality compare, we can
// shrink the and/compare to the smaller type, eliminating the cast.
if (ZExtInst *Cast = dyn_cast<ZExtInst>(LHSI->getOperand(0))) {
IntegerType *Ty = cast<IntegerType>(Cast->getSrcTy());
// Make sure we don't compare the upper bits, SimplifyDemandedBits
// should fold the icmp to true/false in that case.
if (ICI.isEquality() && RHSV.getActiveBits() <= Ty->getBitWidth()) {
Value *NewAnd =
Builder->CreateAnd(Cast->getOperand(0),
ConstantExpr::getTrunc(AndCst, Ty));
NewAnd->takeName(LHSI);
return new ICmpInst(ICI.getPredicate(), NewAnd,
ConstantExpr::getTrunc(RHS, Ty));
}
}
// If this is: (X >> C1) & C2 != C3 (where any shift and any compare
// could exist), turn it into (X & (C2 << C1)) != (C3 << C1). This
// happens a LOT in code produced by the C front-end, for bitfield
// access.
BinaryOperator *Shift = dyn_cast<BinaryOperator>(LHSI->getOperand(0));
if (Shift && !Shift->isShift())
Shift = nullptr;
ConstantInt *ShAmt;
ShAmt = Shift ? dyn_cast<ConstantInt>(Shift->getOperand(1)) : nullptr;
// This seemingly simple opportunity to fold away a shift turns out to
// be rather complicated. See PR17827
// ( http://llvm.org/bugs/show_bug.cgi?id=17827 ) for details.
if (ShAmt) {
bool CanFold = false;
unsigned ShiftOpcode = Shift->getOpcode();
if (ShiftOpcode == Instruction::AShr) {
// There may be some constraints that make this possible,
// but nothing simple has been discovered yet.
CanFold = false;
} else if (ShiftOpcode == Instruction::Shl) {
// For a left shift, we can fold if the comparison is not signed.
// We can also fold a signed comparison if the mask value and
// comparison value are not negative. These constraints may not be
// obvious, but we can prove that they are correct using an SMT
// solver.
if (!ICI.isSigned() || (!AndCst->isNegative() && !RHS->isNegative()))
CanFold = true;
} else if (ShiftOpcode == Instruction::LShr) {
// For a logical right shift, we can fold if the comparison is not
// signed. We can also fold a signed comparison if the shifted mask
// value and the shifted comparison value are not negative.
// These constraints may not be obvious, but we can prove that they
// are correct using an SMT solver.
if (!ICI.isSigned())
CanFold = true;
else {
ConstantInt *ShiftedAndCst =
cast<ConstantInt>(ConstantExpr::getShl(AndCst, ShAmt));
ConstantInt *ShiftedRHSCst =
cast<ConstantInt>(ConstantExpr::getShl(RHS, ShAmt));
if (!ShiftedAndCst->isNegative() && !ShiftedRHSCst->isNegative())
CanFold = true;
}
}
if (CanFold) {
Constant *NewCst;
if (ShiftOpcode == Instruction::Shl)
NewCst = ConstantExpr::getLShr(RHS, ShAmt);
else
NewCst = ConstantExpr::getShl(RHS, ShAmt);
// Check to see if we are shifting out any of the bits being
// compared.
if (ConstantExpr::get(ShiftOpcode, NewCst, ShAmt) != RHS) {
// If we shifted bits out, the fold is not going to work out.
// As a special case, check to see if this means that the
// result is always true or false now.
if (ICI.getPredicate() == ICmpInst::ICMP_EQ)
return ReplaceInstUsesWith(ICI, Builder->getFalse());
if (ICI.getPredicate() == ICmpInst::ICMP_NE)
return ReplaceInstUsesWith(ICI, Builder->getTrue());
} else {
ICI.setOperand(1, NewCst);
Constant *NewAndCst;
if (ShiftOpcode == Instruction::Shl)
NewAndCst = ConstantExpr::getLShr(AndCst, ShAmt);
else
NewAndCst = ConstantExpr::getShl(AndCst, ShAmt);
LHSI->setOperand(1, NewAndCst);
LHSI->setOperand(0, Shift->getOperand(0));
Worklist.Add(Shift); // Shift is dead.
return &ICI;
}
}
}
// Turn ((X >> Y) & C) == 0 into (X & (C << Y)) == 0. The later is
// preferable because it allows the C<<Y expression to be hoisted out
// of a loop if Y is invariant and X is not.
if (Shift && Shift->hasOneUse() && RHSV == 0 &&
ICI.isEquality() && !Shift->isArithmeticShift() &&
!isa<Constant>(Shift->getOperand(0))) {
// Compute C << Y.
Value *NS;
if (Shift->getOpcode() == Instruction::LShr) {
NS = Builder->CreateShl(AndCst, Shift->getOperand(1));
} else {
// Insert a logical shift.
NS = Builder->CreateLShr(AndCst, Shift->getOperand(1));
}
// Compute X & (C << Y).
Value *NewAnd =
Builder->CreateAnd(Shift->getOperand(0), NS, LHSI->getName());
ICI.setOperand(0, NewAnd);
return &ICI;
}
// (icmp pred (and (or (lshr X, Y), X), 1), 0) -->
// (icmp pred (and X, (or (shl 1, Y), 1), 0))
//
// iff pred isn't signed
{
Value *X, *Y, *LShr;
if (!ICI.isSigned() && RHSV == 0) {
if (match(LHSI->getOperand(1), m_One())) {
Constant *One = cast<Constant>(LHSI->getOperand(1));
Value *Or = LHSI->getOperand(0);
if (match(Or, m_Or(m_Value(LShr), m_Value(X))) &&
match(LShr, m_LShr(m_Specific(X), m_Value(Y)))) {
unsigned UsesRemoved = 0;
if (LHSI->hasOneUse())
++UsesRemoved;
if (Or->hasOneUse())
++UsesRemoved;
if (LShr->hasOneUse())
++UsesRemoved;
Value *NewOr = nullptr;
// Compute X & ((1 << Y) | 1)
if (auto *C = dyn_cast<Constant>(Y)) {
if (UsesRemoved >= 1)
NewOr =
ConstantExpr::getOr(ConstantExpr::getNUWShl(One, C), One);
} else {
if (UsesRemoved >= 3)
NewOr = Builder->CreateOr(Builder->CreateShl(One, Y,
LShr->getName(),
/*HasNUW=*/true),
One, Or->getName());
}
if (NewOr) {
Value *NewAnd = Builder->CreateAnd(X, NewOr, LHSI->getName());
ICI.setOperand(0, NewAnd);
return &ICI;
}
}
}
}
}
// Replace ((X & AndCst) > RHSV) with ((X & AndCst) != 0), if any
// bit set in (X & AndCst) will produce a result greater than RHSV.
if (ICI.getPredicate() == ICmpInst::ICMP_UGT) {
unsigned NTZ = AndCst->getValue().countTrailingZeros();
if ((NTZ < AndCst->getBitWidth()) &&
APInt::getOneBitSet(AndCst->getBitWidth(), NTZ).ugt(RHSV))
return new ICmpInst(ICmpInst::ICMP_NE, LHSI,
Constant::getNullValue(RHS->getType()));
}
}
// Try to optimize things like "A[i]&42 == 0" to index computations.
if (LoadInst *LI = dyn_cast<LoadInst>(LHSI->getOperand(0))) {
if (GetElementPtrInst *GEP =
dyn_cast<GetElementPtrInst>(LI->getOperand(0)))
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(GEP->getOperand(0)))
if (GV->isConstant() && GV->hasDefinitiveInitializer() &&
!LI->isVolatile() && isa<ConstantInt>(LHSI->getOperand(1))) {
ConstantInt *C = cast<ConstantInt>(LHSI->getOperand(1));
if (Instruction *Res = FoldCmpLoadFromIndexedGlobal(GEP, GV,ICI, C))
return Res;
}
}
// X & -C == -C -> X > u ~C
// X & -C != -C -> X <= u ~C
// iff C is a power of 2
if (ICI.isEquality() && RHS == LHSI->getOperand(1) && (-RHSV).isPowerOf2())
return new ICmpInst(
ICI.getPredicate() == ICmpInst::ICMP_EQ ? ICmpInst::ICMP_UGT
: ICmpInst::ICMP_ULE,
LHSI->getOperand(0), SubOne(RHS));
break;
case Instruction::Or: {
if (!ICI.isEquality() || !RHS->isNullValue() || !LHSI->hasOneUse())
break;
Value *P, *Q;
if (match(LHSI, m_Or(m_PtrToInt(m_Value(P)), m_PtrToInt(m_Value(Q))))) {
// Simplify icmp eq (or (ptrtoint P), (ptrtoint Q)), 0
// -> and (icmp eq P, null), (icmp eq Q, null).
Value *ICIP = Builder->CreateICmp(ICI.getPredicate(), P,
Constant::getNullValue(P->getType()));
Value *ICIQ = Builder->CreateICmp(ICI.getPredicate(), Q,
Constant::getNullValue(Q->getType()));
Instruction *Op;
if (ICI.getPredicate() == ICmpInst::ICMP_EQ)
Op = BinaryOperator::CreateAnd(ICIP, ICIQ);
else
Op = BinaryOperator::CreateOr(ICIP, ICIQ);
return Op;
}
break;
}
case Instruction::Mul: { // (icmp pred (mul X, Val), CI)
ConstantInt *Val = dyn_cast<ConstantInt>(LHSI->getOperand(1));
if (!Val) break;
// If this is a signed comparison to 0 and the mul is sign preserving,
// use the mul LHS operand instead.
ICmpInst::Predicate pred = ICI.getPredicate();
if (isSignTest(pred, RHS) && !Val->isZero() &&
cast<BinaryOperator>(LHSI)->hasNoSignedWrap())
return new ICmpInst(Val->isNegative() ?
ICmpInst::getSwappedPredicate(pred) : pred,
LHSI->getOperand(0),
Constant::getNullValue(RHS->getType()));
break;
}
case Instruction::Shl: { // (icmp pred (shl X, ShAmt), CI)
uint32_t TypeBits = RHSV.getBitWidth();
ConstantInt *ShAmt = dyn_cast<ConstantInt>(LHSI->getOperand(1));
if (!ShAmt) {
Value *X;
// (1 << X) pred P2 -> X pred Log2(P2)
if (match(LHSI, m_Shl(m_One(), m_Value(X)))) {
bool RHSVIsPowerOf2 = RHSV.isPowerOf2();
ICmpInst::Predicate Pred = ICI.getPredicate();
if (ICI.isUnsigned()) {
if (!RHSVIsPowerOf2) {
// (1 << X) < 30 -> X <= 4
// (1 << X) <= 30 -> X <= 4
// (1 << X) >= 30 -> X > 4
// (1 << X) > 30 -> X > 4
if (Pred == ICmpInst::ICMP_ULT)
Pred = ICmpInst::ICMP_ULE;
else if (Pred == ICmpInst::ICMP_UGE)
Pred = ICmpInst::ICMP_UGT;
}
unsigned RHSLog2 = RHSV.logBase2();
// (1 << X) >= 2147483648 -> X >= 31 -> X == 31
// (1 << X) < 2147483648 -> X < 31 -> X != 31
if (RHSLog2 == TypeBits-1) {
if (Pred == ICmpInst::ICMP_UGE)
Pred = ICmpInst::ICMP_EQ;
else if (Pred == ICmpInst::ICMP_ULT)
Pred = ICmpInst::ICMP_NE;
}
return new ICmpInst(Pred, X,
ConstantInt::get(RHS->getType(), RHSLog2));
} else if (ICI.isSigned()) {
if (RHSV.isAllOnesValue()) {
// (1 << X) <= -1 -> X == 31
if (Pred == ICmpInst::ICMP_SLE)
return new ICmpInst(ICmpInst::ICMP_EQ, X,
ConstantInt::get(RHS->getType(), TypeBits-1));
// (1 << X) > -1 -> X != 31
if (Pred == ICmpInst::ICMP_SGT)
return new ICmpInst(ICmpInst::ICMP_NE, X,
ConstantInt::get(RHS->getType(), TypeBits-1));
} else if (!RHSV) {
// (1 << X) < 0 -> X == 31
// (1 << X) <= 0 -> X == 31
if (Pred == ICmpInst::ICMP_SLT || Pred == ICmpInst::ICMP_SLE)
return new ICmpInst(ICmpInst::ICMP_EQ, X,
ConstantInt::get(RHS->getType(), TypeBits-1));
// (1 << X) >= 0 -> X != 31
// (1 << X) > 0 -> X != 31
if (Pred == ICmpInst::ICMP_SGT || Pred == ICmpInst::ICMP_SGE)
return new ICmpInst(ICmpInst::ICMP_NE, X,
ConstantInt::get(RHS->getType(), TypeBits-1));
}
} else if (ICI.isEquality()) {
if (RHSVIsPowerOf2)
return new ICmpInst(
Pred, X, ConstantInt::get(RHS->getType(), RHSV.logBase2()));
}
}
break;
}
// Check that the shift amount is in range. If not, don't perform
// undefined shifts. When the shift is visited it will be
// simplified.
if (ShAmt->uge(TypeBits))
break;
if (ICI.isEquality()) {
// If we are comparing against bits always shifted out, the
// comparison cannot succeed.
Constant *Comp =
ConstantExpr::getShl(ConstantExpr::getLShr(RHS, ShAmt),
ShAmt);
if (Comp != RHS) {// Comparing against a bit that we know is zero.
bool IsICMP_NE = ICI.getPredicate() == ICmpInst::ICMP_NE;
Constant *Cst = Builder->getInt1(IsICMP_NE);
return ReplaceInstUsesWith(ICI, Cst);
}
// If the shift is NUW, then it is just shifting out zeros, no need for an
// AND.
if (cast<BinaryOperator>(LHSI)->hasNoUnsignedWrap())
return new ICmpInst(ICI.getPredicate(), LHSI->getOperand(0),
ConstantExpr::getLShr(RHS, ShAmt));
// If the shift is NSW and we compare to 0, then it is just shifting out
// sign bits, no need for an AND either.
if (cast<BinaryOperator>(LHSI)->hasNoSignedWrap() && RHSV == 0)
return new ICmpInst(ICI.getPredicate(), LHSI->getOperand(0),
ConstantExpr::getLShr(RHS, ShAmt));
if (LHSI->hasOneUse()) {
// Otherwise strength reduce the shift into an and.
uint32_t ShAmtVal = (uint32_t)ShAmt->getLimitedValue(TypeBits);
Constant *Mask = Builder->getInt(APInt::getLowBitsSet(TypeBits,
TypeBits - ShAmtVal));
Value *And =
Builder->CreateAnd(LHSI->getOperand(0),Mask, LHSI->getName()+".mask");
return new ICmpInst(ICI.getPredicate(), And,
ConstantExpr::getLShr(RHS, ShAmt));
}
}
// If this is a signed comparison to 0 and the shift is sign preserving,
// use the shift LHS operand instead.
ICmpInst::Predicate pred = ICI.getPredicate();
if (isSignTest(pred, RHS) &&
cast<BinaryOperator>(LHSI)->hasNoSignedWrap())
return new ICmpInst(pred,
LHSI->getOperand(0),
Constant::getNullValue(RHS->getType()));
// Otherwise, if this is a comparison of the sign bit, simplify to and/test.
bool TrueIfSigned = false;
if (LHSI->hasOneUse() &&
isSignBitCheck(ICI.getPredicate(), RHS, TrueIfSigned)) {
// (X << 31) <s 0 --> (X&1) != 0
Constant *Mask = ConstantInt::get(LHSI->getOperand(0)->getType(),
APInt::getOneBitSet(TypeBits,
TypeBits-ShAmt->getZExtValue()-1));
Value *And =
Builder->CreateAnd(LHSI->getOperand(0), Mask, LHSI->getName()+".mask");
return new ICmpInst(TrueIfSigned ? ICmpInst::ICMP_NE : ICmpInst::ICMP_EQ,
And, Constant::getNullValue(And->getType()));
}
#if 0 // HLSL Change Begins: Disable optimization, it introduces new bitwidths
// Transform (icmp pred iM (shl iM %v, N), CI)
// -> (icmp pred i(M-N) (trunc %v iM to i(M-N)), (trunc (CI>>N))
// Transform the shl to a trunc if (trunc (CI>>N)) has no loss and M-N.
// This enables to get rid of the shift in favor of a trunc which can be
// free on the target. It has the additional benefit of comparing to a
// smaller constant, which will be target friendly.
unsigned Amt = ShAmt->getLimitedValue(TypeBits-1);
if (LHSI->hasOneUse() &&
Amt != 0 && RHSV.countTrailingZeros() >= Amt) {
Type *NTy = IntegerType::get(ICI.getContext(), TypeBits - Amt);
Constant *NCI = ConstantExpr::getTrunc(
ConstantExpr::getAShr(RHS,
ConstantInt::get(RHS->getType(), Amt)),
NTy);
return new ICmpInst(ICI.getPredicate(),
Builder->CreateTrunc(LHSI->getOperand(0), NTy),
NCI);
}
#endif // HLSL Change Ends
break;
}
case Instruction::LShr: // (icmp pred (shr X, ShAmt), CI)
case Instruction::AShr: {
// Handle equality comparisons of shift-by-constant.
BinaryOperator *BO = cast<BinaryOperator>(LHSI);
if (ConstantInt *ShAmt = dyn_cast<ConstantInt>(LHSI->getOperand(1))) {
if (Instruction *Res = FoldICmpShrCst(ICI, BO, ShAmt))
return Res;
}
// Handle exact shr's.
if (ICI.isEquality() && BO->isExact() && BO->hasOneUse()) {
if (RHSV.isMinValue())
return new ICmpInst(ICI.getPredicate(), BO->getOperand(0), RHS);
}
break;
}
case Instruction::SDiv:
case Instruction::UDiv:
// Fold: icmp pred ([us]div X, C1), C2 -> range test
// Fold this div into the comparison, producing a range check.
// Determine, based on the divide type, what the range is being
// checked. If there is an overflow on the low or high side, remember
// it, otherwise compute the range [low, hi) bounding the new value.
// See: InsertRangeTest above for the kinds of replacements possible.
if (ConstantInt *DivRHS = dyn_cast<ConstantInt>(LHSI->getOperand(1)))
if (Instruction *R = FoldICmpDivCst(ICI, cast<BinaryOperator>(LHSI),
DivRHS))
return R;
break;
case Instruction::Sub: {
ConstantInt *LHSC = dyn_cast<ConstantInt>(LHSI->getOperand(0));
if (!LHSC) break;
const APInt &LHSV = LHSC->getValue();
// C1-X <u C2 -> (X|(C2-1)) == C1
// iff C1 & (C2-1) == C2-1
// C2 is a power of 2
if (ICI.getPredicate() == ICmpInst::ICMP_ULT && LHSI->hasOneUse() &&
RHSV.isPowerOf2() && (LHSV & (RHSV - 1)) == (RHSV - 1))
return new ICmpInst(ICmpInst::ICMP_EQ,
Builder->CreateOr(LHSI->getOperand(1), RHSV - 1),
LHSC);
// C1-X >u C2 -> (X|C2) != C1
// iff C1 & C2 == C2
// C2+1 is a power of 2
if (ICI.getPredicate() == ICmpInst::ICMP_UGT && LHSI->hasOneUse() &&
(RHSV + 1).isPowerOf2() && (LHSV & RHSV) == RHSV)
return new ICmpInst(ICmpInst::ICMP_NE,
Builder->CreateOr(LHSI->getOperand(1), RHSV), LHSC);
break;
}
case Instruction::Add:
// Fold: icmp pred (add X, C1), C2
if (!ICI.isEquality()) {
ConstantInt *LHSC = dyn_cast<ConstantInt>(LHSI->getOperand(1));
if (!LHSC) break;
const APInt &LHSV = LHSC->getValue();
ConstantRange CR = ICI.makeConstantRange(ICI.getPredicate(), RHSV)
.subtract(LHSV);
if (ICI.isSigned()) {
if (CR.getLower().isSignBit()) {
return new ICmpInst(ICmpInst::ICMP_SLT, LHSI->getOperand(0),
Builder->getInt(CR.getUpper()));
} else if (CR.getUpper().isSignBit()) {
return new ICmpInst(ICmpInst::ICMP_SGE, LHSI->getOperand(0),
Builder->getInt(CR.getLower()));
}
} else {
if (CR.getLower().isMinValue()) {
return new ICmpInst(ICmpInst::ICMP_ULT, LHSI->getOperand(0),
Builder->getInt(CR.getUpper()));
} else if (CR.getUpper().isMinValue()) {
return new ICmpInst(ICmpInst::ICMP_UGE, LHSI->getOperand(0),
Builder->getInt(CR.getLower()));
}
}
// X-C1 <u C2 -> (X & -C2) == C1
// iff C1 & (C2-1) == 0
// C2 is a power of 2
if (ICI.getPredicate() == ICmpInst::ICMP_ULT && LHSI->hasOneUse() &&
RHSV.isPowerOf2() && (LHSV & (RHSV - 1)) == 0)
return new ICmpInst(ICmpInst::ICMP_EQ,
Builder->CreateAnd(LHSI->getOperand(0), -RHSV),
ConstantExpr::getNeg(LHSC));
// X-C1 >u C2 -> (X & ~C2) != C1
// iff C1 & C2 == 0
// C2+1 is a power of 2
if (ICI.getPredicate() == ICmpInst::ICMP_UGT && LHSI->hasOneUse() &&
(RHSV + 1).isPowerOf2() && (LHSV & RHSV) == 0)
return new ICmpInst(ICmpInst::ICMP_NE,
Builder->CreateAnd(LHSI->getOperand(0), ~RHSV),
ConstantExpr::getNeg(LHSC));
}
break;
}
// Simplify icmp_eq and icmp_ne instructions with integer constant RHS.
if (ICI.isEquality()) {
bool isICMP_NE = ICI.getPredicate() == ICmpInst::ICMP_NE;
// If the first operand is (add|sub|and|or|xor|rem) with a constant, and
// the second operand is a constant, simplify a bit.
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(LHSI)) {
switch (BO->getOpcode()) {
case Instruction::SRem:
// If we have a signed (X % (2^c)) == 0, turn it into an unsigned one.
if (RHSV == 0 && isa<ConstantInt>(BO->getOperand(1)) &&BO->hasOneUse()){
const APInt &V = cast<ConstantInt>(BO->getOperand(1))->getValue();
if (V.sgt(1) && V.isPowerOf2()) {
Value *NewRem =
Builder->CreateURem(BO->getOperand(0), BO->getOperand(1),
BO->getName());
return new ICmpInst(ICI.getPredicate(), NewRem,
Constant::getNullValue(BO->getType()));
}
}
break;
case Instruction::Add:
// Replace ((add A, B) != C) with (A != C-B) if B & C are constants.
if (ConstantInt *BOp1C = dyn_cast<ConstantInt>(BO->getOperand(1))) {
if (BO->hasOneUse())
return new ICmpInst(ICI.getPredicate(), BO->getOperand(0),
ConstantExpr::getSub(RHS, BOp1C));
} else if (RHSV == 0) {
// Replace ((add A, B) != 0) with (A != -B) if A or B is
// efficiently invertible, or if the add has just this one use.
Value *BOp0 = BO->getOperand(0), *BOp1 = BO->getOperand(1);
if (Value *NegVal = dyn_castNegVal(BOp1))
return new ICmpInst(ICI.getPredicate(), BOp0, NegVal);
if (Value *NegVal = dyn_castNegVal(BOp0))
return new ICmpInst(ICI.getPredicate(), NegVal, BOp1);
if (BO->hasOneUse()) {
Value *Neg = Builder->CreateNeg(BOp1);
Neg->takeName(BO);
return new ICmpInst(ICI.getPredicate(), BOp0, Neg);
}
}
break;
case Instruction::Xor:
// For the xor case, we can xor two constants together, eliminating
// the explicit xor.
if (Constant *BOC = dyn_cast<Constant>(BO->getOperand(1))) {
return new ICmpInst(ICI.getPredicate(), BO->getOperand(0),
ConstantExpr::getXor(RHS, BOC));
} else if (RHSV == 0) {
// Replace ((xor A, B) != 0) with (A != B)
return new ICmpInst(ICI.getPredicate(), BO->getOperand(0),
BO->getOperand(1));
}
break;
case Instruction::Sub:
// Replace ((sub A, B) != C) with (B != A-C) if A & C are constants.
if (ConstantInt *BOp0C = dyn_cast<ConstantInt>(BO->getOperand(0))) {
if (BO->hasOneUse())
return new ICmpInst(ICI.getPredicate(), BO->getOperand(1),
ConstantExpr::getSub(BOp0C, RHS));
} else if (RHSV == 0) {
// Replace ((sub A, B) != 0) with (A != B)
return new ICmpInst(ICI.getPredicate(), BO->getOperand(0),
BO->getOperand(1));
}
break;
case Instruction::Or:
// If bits are being or'd in that are not present in the constant we
// are comparing against, then the comparison could never succeed!
if (ConstantInt *BOC = dyn_cast<ConstantInt>(BO->getOperand(1))) {
Constant *NotCI = ConstantExpr::getNot(RHS);
if (!ConstantExpr::getAnd(BOC, NotCI)->isNullValue())
return ReplaceInstUsesWith(ICI, Builder->getInt1(isICMP_NE));
}
break;
case Instruction::And:
if (ConstantInt *BOC = dyn_cast<ConstantInt>(BO->getOperand(1))) {
// If bits are being compared against that are and'd out, then the
// comparison can never succeed!
if ((RHSV & ~BOC->getValue()) != 0)
return ReplaceInstUsesWith(ICI, Builder->getInt1(isICMP_NE));
// If we have ((X & C) == C), turn it into ((X & C) != 0).
if (RHS == BOC && RHSV.isPowerOf2())
return new ICmpInst(isICMP_NE ? ICmpInst::ICMP_EQ :
ICmpInst::ICMP_NE, LHSI,
Constant::getNullValue(RHS->getType()));
// Don't perform the following transforms if the AND has multiple uses
if (!BO->hasOneUse())
break;
// Replace (and X, (1 << size(X)-1) != 0) with x s< 0
if (BOC->getValue().isSignBit()) {
Value *X = BO->getOperand(0);
Constant *Zero = Constant::getNullValue(X->getType());
ICmpInst::Predicate pred = isICMP_NE ?
ICmpInst::ICMP_SLT : ICmpInst::ICMP_SGE;
return new ICmpInst(pred, X, Zero);
}
// ((X & ~7) == 0) --> X < 8
if (RHSV == 0 && isHighOnes(BOC)) {
Value *X = BO->getOperand(0);
Constant *NegX = ConstantExpr::getNeg(BOC);
ICmpInst::Predicate pred = isICMP_NE ?
ICmpInst::ICMP_UGE : ICmpInst::ICMP_ULT;
return new ICmpInst(pred, X, NegX);
}
}
break;
case Instruction::Mul:
if (RHSV == 0 && BO->hasNoSignedWrap()) {
if (ConstantInt *BOC = dyn_cast<ConstantInt>(BO->getOperand(1))) {
// The trivial case (mul X, 0) is handled by InstSimplify
// General case : (mul X, C) != 0 iff X != 0
// (mul X, C) == 0 iff X == 0
if (!BOC->isZero())
return new ICmpInst(ICI.getPredicate(), BO->getOperand(0),
Constant::getNullValue(RHS->getType()));
}
}
break;
default: break;
}
} else if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(LHSI)) {
// Handle icmp {eq|ne} <intrinsic>, intcst.
switch (II->getIntrinsicID()) {
case Intrinsic::bswap:
Worklist.Add(II);
ICI.setOperand(0, II->getArgOperand(0));
ICI.setOperand(1, Builder->getInt(RHSV.byteSwap()));
return &ICI;
case Intrinsic::ctlz:
case Intrinsic::cttz:
// ctz(A) == bitwidth(a) -> A == 0 and likewise for !=
if (RHSV == RHS->getType()->getBitWidth()) {
Worklist.Add(II);
ICI.setOperand(0, II->getArgOperand(0));
ICI.setOperand(1, ConstantInt::get(RHS->getType(), 0));
return &ICI;
}
break;
case Intrinsic::ctpop:
// popcount(A) == 0 -> A == 0 and likewise for !=
if (RHS->isZero()) {
Worklist.Add(II);
ICI.setOperand(0, II->getArgOperand(0));
ICI.setOperand(1, RHS);
return &ICI;
}
break;
default:
break;
}
}
}
return nullptr;
}
/// visitICmpInstWithCastAndCast - Handle icmp (cast x to y), (cast/cst).
/// We only handle extending casts so far.
///
Instruction *InstCombiner::visitICmpInstWithCastAndCast(ICmpInst &ICI) {
const CastInst *LHSCI = cast<CastInst>(ICI.getOperand(0));
Value *LHSCIOp = LHSCI->getOperand(0);
Type *SrcTy = LHSCIOp->getType();
Type *DestTy = LHSCI->getType();
Value *RHSCIOp;
// Turn icmp (ptrtoint x), (ptrtoint/c) into a compare of the input if the
// integer type is the same size as the pointer type.
if (LHSCI->getOpcode() == Instruction::PtrToInt &&
DL.getPointerTypeSizeInBits(SrcTy) == DestTy->getIntegerBitWidth()) {
Value *RHSOp = nullptr;
if (PtrToIntOperator *RHSC = dyn_cast<PtrToIntOperator>(ICI.getOperand(1))) {
Value *RHSCIOp = RHSC->getOperand(0);
if (RHSCIOp->getType()->getPointerAddressSpace() ==
LHSCIOp->getType()->getPointerAddressSpace()) {
RHSOp = RHSC->getOperand(0);
// If the pointer types don't match, insert a bitcast.
if (LHSCIOp->getType() != RHSOp->getType())
RHSOp = Builder->CreateBitCast(RHSOp, LHSCIOp->getType());
}
} else if (Constant *RHSC = dyn_cast<Constant>(ICI.getOperand(1)))
RHSOp = ConstantExpr::getIntToPtr(RHSC, SrcTy);
if (RHSOp)
return new ICmpInst(ICI.getPredicate(), LHSCIOp, RHSOp);
}
// The code below only handles extension cast instructions, so far.
// Enforce this.
if (LHSCI->getOpcode() != Instruction::ZExt &&
LHSCI->getOpcode() != Instruction::SExt)
return nullptr;
bool isSignedExt = LHSCI->getOpcode() == Instruction::SExt;
bool isSignedCmp = ICI.isSigned();
if (CastInst *CI = dyn_cast<CastInst>(ICI.getOperand(1))) {
// Not an extension from the same type?
RHSCIOp = CI->getOperand(0);
if (RHSCIOp->getType() != LHSCIOp->getType())
return nullptr;
// If the signedness of the two casts doesn't agree (i.e. one is a sext
// and the other is a zext), then we can't handle this.
if (CI->getOpcode() != LHSCI->getOpcode())
return nullptr;
// Deal with equality cases early.
if (ICI.isEquality())
return new ICmpInst(ICI.getPredicate(), LHSCIOp, RHSCIOp);
// A signed comparison of sign extended values simplifies into a
// signed comparison.
if (isSignedCmp && isSignedExt)
return new ICmpInst(ICI.getPredicate(), LHSCIOp, RHSCIOp);
// The other three cases all fold into an unsigned comparison.
return new ICmpInst(ICI.getUnsignedPredicate(), LHSCIOp, RHSCIOp);
}
// If we aren't dealing with a constant on the RHS, exit early
ConstantInt *CI = dyn_cast<ConstantInt>(ICI.getOperand(1));
if (!CI)
return nullptr;
// Compute the constant that would happen if we truncated to SrcTy then
// reextended to DestTy.
Constant *Res1 = ConstantExpr::getTrunc(CI, SrcTy);
Constant *Res2 = ConstantExpr::getCast(LHSCI->getOpcode(),
Res1, DestTy);
// If the re-extended constant didn't change...
if (Res2 == CI) {
// Deal with equality cases early.
if (ICI.isEquality())
return new ICmpInst(ICI.getPredicate(), LHSCIOp, Res1);
// A signed comparison of sign extended values simplifies into a
// signed comparison.
if (isSignedExt && isSignedCmp)
return new ICmpInst(ICI.getPredicate(), LHSCIOp, Res1);
// The other three cases all fold into an unsigned comparison.
return new ICmpInst(ICI.getUnsignedPredicate(), LHSCIOp, Res1);
}
// The re-extended constant changed so the constant cannot be represented
// in the shorter type. Consequently, we cannot emit a simple comparison.
// All the cases that fold to true or false will have already been handled
// by SimplifyICmpInst, so only deal with the tricky case.
if (isSignedCmp || !isSignedExt)
return nullptr;
// Evaluate the comparison for LT (we invert for GT below). LE and GE cases
// should have been folded away previously and not enter in here.
// We're performing an unsigned comp with a sign extended value.
// This is true if the input is >= 0. [aka >s -1]
Constant *NegOne = Constant::getAllOnesValue(SrcTy);
Value *Result = Builder->CreateICmpSGT(LHSCIOp, NegOne, ICI.getName());
// Finally, return the value computed.
if (ICI.getPredicate() == ICmpInst::ICMP_ULT)
return ReplaceInstUsesWith(ICI, Result);
assert(ICI.getPredicate() == ICmpInst::ICMP_UGT && "ICmp should be folded!");
return BinaryOperator::CreateNot(Result);
}
/// ProcessUGT_ADDCST_ADD - The caller has matched a pattern of the form:
/// I = icmp ugt (add (add A, B), CI2), CI1
/// If this is of the form:
/// sum = a + b
/// if (sum+128 >u 255)
/// Then replace it with llvm.sadd.with.overflow.i8.
///
static Instruction *ProcessUGT_ADDCST_ADD(ICmpInst &I, Value *A, Value *B,
ConstantInt *CI2, ConstantInt *CI1,
InstCombiner &IC) {
// The transformation we're trying to do here is to transform this into an
// llvm.sadd.with.overflow. To do this, we have to replace the original add
// with a narrower add, and discard the add-with-constant that is part of the
// range check (if we can't eliminate it, this isn't profitable).
// In order to eliminate the add-with-constant, the compare can be its only
// use.
Instruction *AddWithCst = cast<Instruction>(I.getOperand(0));
if (!AddWithCst->hasOneUse()) return nullptr;
// If CI2 is 2^7, 2^15, 2^31, then it might be an sadd.with.overflow.
if (!CI2->getValue().isPowerOf2()) return nullptr;
unsigned NewWidth = CI2->getValue().countTrailingZeros();
if (NewWidth != 7 && NewWidth != 15 && NewWidth != 31) return nullptr;
// The width of the new add formed is 1 more than the bias.
++NewWidth;
// Check to see that CI1 is an all-ones value with NewWidth bits.
if (CI1->getBitWidth() == NewWidth ||
CI1->getValue() != APInt::getLowBitsSet(CI1->getBitWidth(), NewWidth))
return nullptr;
// This is only really a signed overflow check if the inputs have been
// sign-extended; check for that condition. For example, if CI2 is 2^31 and
// the operands of the add are 64 bits wide, we need at least 33 sign bits.
unsigned NeededSignBits = CI1->getBitWidth() - NewWidth + 1;
if (IC.ComputeNumSignBits(A, 0, &I) < NeededSignBits ||
IC.ComputeNumSignBits(B, 0, &I) < NeededSignBits)
return nullptr;
// In order to replace the original add with a narrower
// llvm.sadd.with.overflow, the only uses allowed are the add-with-constant
// and truncates that discard the high bits of the add. Verify that this is
// the case.
Instruction *OrigAdd = cast<Instruction>(AddWithCst->getOperand(0));
for (User *U : OrigAdd->users()) {
if (U == AddWithCst) continue;
// Only accept truncates for now. We would really like a nice recursive
// predicate like SimplifyDemandedBits, but which goes downwards the use-def
// chain to see which bits of a value are actually demanded. If the
// original add had another add which was then immediately truncated, we
// could still do the transformation.
TruncInst *TI = dyn_cast<TruncInst>(U);
if (!TI || TI->getType()->getPrimitiveSizeInBits() > NewWidth)
return nullptr;
}
// If the pattern matches, truncate the inputs to the narrower type and
// use the sadd_with_overflow intrinsic to efficiently compute both the
// result and the overflow bit.
Module *M = I.getParent()->getParent()->getParent();
Type *NewType = IntegerType::get(OrigAdd->getContext(), NewWidth);
Value *F = Intrinsic::getDeclaration(M, Intrinsic::sadd_with_overflow,
NewType);
InstCombiner::BuilderTy *Builder = IC.Builder;
// Put the new code above the original add, in case there are any uses of the
// add between the add and the compare.
Builder->SetInsertPoint(OrigAdd);
Value *TruncA = Builder->CreateTrunc(A, NewType, A->getName()+".trunc");
Value *TruncB = Builder->CreateTrunc(B, NewType, B->getName()+".trunc");
CallInst *Call = Builder->CreateCall(F, {TruncA, TruncB}, "sadd");
Value *Add = Builder->CreateExtractValue(Call, 0, "sadd.result");
Value *ZExt = Builder->CreateZExt(Add, OrigAdd->getType());
// The inner add was the result of the narrow add, zero extended to the
// wider type. Replace it with the result computed by the intrinsic.
IC.ReplaceInstUsesWith(*OrigAdd, ZExt);
// The original icmp gets replaced with the overflow value.
return ExtractValueInst::Create(Call, 1, "sadd.overflow");
}
bool InstCombiner::OptimizeOverflowCheck(OverflowCheckFlavor OCF, Value *LHS,
Value *RHS, Instruction &OrigI,
Value *&Result, Constant *&Overflow) {
if (OrigI.isCommutative() && isa<Constant>(LHS) && !isa<Constant>(RHS))
std::swap(LHS, RHS);
auto SetResult = [&](Value *OpResult, Constant *OverflowVal, bool ReuseName) {
Result = OpResult;
Overflow = OverflowVal;
if (ReuseName)
Result->takeName(&OrigI);
return true;
};
// If the overflow check was an add followed by a compare, the insertion point
// may be pointing to the compare. We want to insert the new instructions
// before the add in case there are uses of the add between the add and the
// compare.
Builder->SetInsertPoint(&OrigI);
switch (OCF) {
case OCF_INVALID:
llvm_unreachable("bad overflow check kind!");
case OCF_UNSIGNED_ADD: {
OverflowResult OR = computeOverflowForUnsignedAdd(LHS, RHS, &OrigI);
if (OR == OverflowResult::NeverOverflows)
return SetResult(Builder->CreateNUWAdd(LHS, RHS), Builder->getFalse(),
true);
if (OR == OverflowResult::AlwaysOverflows)
return SetResult(Builder->CreateAdd(LHS, RHS), Builder->getTrue(), true);
}
// FALL THROUGH uadd into sadd
LLVM_FALLTHROUGH; // HLSL Change
case OCF_SIGNED_ADD: {
// X + 0 -> {X, false}
if (match(RHS, m_Zero()))
return SetResult(LHS, Builder->getFalse(), false);
// We can strength reduce this signed add into a regular add if we can prove
// that it will never overflow.
if (OCF == OCF_SIGNED_ADD)
if (WillNotOverflowSignedAdd(LHS, RHS, OrigI))
return SetResult(Builder->CreateNSWAdd(LHS, RHS), Builder->getFalse(),
true);
break;
}
case OCF_UNSIGNED_SUB:
case OCF_SIGNED_SUB: {
// X - 0 -> {X, false}
if (match(RHS, m_Zero()))
return SetResult(LHS, Builder->getFalse(), false);
if (OCF == OCF_SIGNED_SUB) {
if (WillNotOverflowSignedSub(LHS, RHS, OrigI))
return SetResult(Builder->CreateNSWSub(LHS, RHS), Builder->getFalse(),
true);
} else {
if (WillNotOverflowUnsignedSub(LHS, RHS, OrigI))
return SetResult(Builder->CreateNUWSub(LHS, RHS), Builder->getFalse(),
true);
}
break;
}
case OCF_UNSIGNED_MUL: {
OverflowResult OR = computeOverflowForUnsignedMul(LHS, RHS, &OrigI);
if (OR == OverflowResult::NeverOverflows)
return SetResult(Builder->CreateNUWMul(LHS, RHS), Builder->getFalse(),
true);
if (OR == OverflowResult::AlwaysOverflows)
return SetResult(Builder->CreateMul(LHS, RHS), Builder->getTrue(), true);
} LLVM_FALLTHROUGH; // HLSL CHANGE
case OCF_SIGNED_MUL:
// X * undef -> undef
if (isa<UndefValue>(RHS))
return SetResult(RHS, UndefValue::get(Builder->getInt1Ty()), false);
// X * 0 -> {0, false}
if (match(RHS, m_Zero()))
return SetResult(RHS, Builder->getFalse(), false);
// X * 1 -> {X, false}
if (match(RHS, m_One()))
return SetResult(LHS, Builder->getFalse(), false);
if (OCF == OCF_SIGNED_MUL)
if (WillNotOverflowSignedMul(LHS, RHS, OrigI))
return SetResult(Builder->CreateNSWMul(LHS, RHS), Builder->getFalse(),
true);
break;
}
return false;
}
/// \brief Recognize and process idiom involving test for multiplication
/// overflow.
///
/// The caller has matched a pattern of the form:
/// I = cmp u (mul(zext A, zext B), V
/// The function checks if this is a test for overflow and if so replaces
/// multiplication with call to 'mul.with.overflow' intrinsic.
///
/// \param I Compare instruction.
/// \param MulVal Result of 'mult' instruction. It is one of the arguments of
/// the compare instruction. Must be of integer type.
/// \param OtherVal The other argument of compare instruction.
/// \returns Instruction which must replace the compare instruction, NULL if no
/// replacement required.
static Instruction *ProcessUMulZExtIdiom(ICmpInst &I, Value *MulVal,
Value *OtherVal, InstCombiner &IC) {
// Don't bother doing this transformation for pointers, don't do it for
// vectors.
if (!isa<IntegerType>(MulVal->getType()))
return nullptr;
assert(I.getOperand(0) == MulVal || I.getOperand(1) == MulVal);
assert(I.getOperand(0) == OtherVal || I.getOperand(1) == OtherVal);
Instruction *MulInstr = cast<Instruction>(MulVal);
assert(MulInstr->getOpcode() == Instruction::Mul);
auto *LHS = cast<ZExtOperator>(MulInstr->getOperand(0)),
*RHS = cast<ZExtOperator>(MulInstr->getOperand(1));
assert(LHS->getOpcode() == Instruction::ZExt);
assert(RHS->getOpcode() == Instruction::ZExt);
Value *A = LHS->getOperand(0), *B = RHS->getOperand(0);
// Calculate type and width of the result produced by mul.with.overflow.
Type *TyA = A->getType(), *TyB = B->getType();
unsigned WidthA = TyA->getPrimitiveSizeInBits(),
WidthB = TyB->getPrimitiveSizeInBits();
unsigned MulWidth;
Type *MulType;
if (WidthB > WidthA) {
MulWidth = WidthB;
MulType = TyB;
} else {
MulWidth = WidthA;
MulType = TyA;
}
// In order to replace the original mul with a narrower mul.with.overflow,
// all uses must ignore upper bits of the product. The number of used low
// bits must be not greater than the width of mul.with.overflow.
if (MulVal->hasNUsesOrMore(2))
for (User *U : MulVal->users()) {
if (U == &I)
continue;
if (TruncInst *TI = dyn_cast<TruncInst>(U)) {
// Check if truncation ignores bits above MulWidth.
unsigned TruncWidth = TI->getType()->getPrimitiveSizeInBits();
if (TruncWidth > MulWidth)
return nullptr;
} else if (BinaryOperator *BO = dyn_cast<BinaryOperator>(U)) {
// Check if AND ignores bits above MulWidth.
if (BO->getOpcode() != Instruction::And)
return nullptr;
if (ConstantInt *CI = dyn_cast<ConstantInt>(BO->getOperand(1))) {
const APInt &CVal = CI->getValue();
if (CVal.getBitWidth() - CVal.countLeadingZeros() > MulWidth)
return nullptr;
}
} else {
// Other uses prohibit this transformation.
return nullptr;
}
}
// Recognize patterns
switch (I.getPredicate()) {
case ICmpInst::ICMP_EQ:
case ICmpInst::ICMP_NE:
// Recognize pattern:
// mulval = mul(zext A, zext B)
// cmp eq/neq mulval, zext trunc mulval
if (ZExtInst *Zext = dyn_cast<ZExtInst>(OtherVal))
if (Zext->hasOneUse()) {
Value *ZextArg = Zext->getOperand(0);
if (TruncInst *Trunc = dyn_cast<TruncInst>(ZextArg))
if (Trunc->getType()->getPrimitiveSizeInBits() == MulWidth)
break; //Recognized
}
// Recognize pattern:
// mulval = mul(zext A, zext B)
// cmp eq/neq mulval, and(mulval, mask), mask selects low MulWidth bits.
ConstantInt *CI;
Value *ValToMask;
if (match(OtherVal, m_And(m_Value(ValToMask), m_ConstantInt(CI)))) {
if (ValToMask != MulVal)
return nullptr;
const APInt &CVal = CI->getValue() + 1;
if (CVal.isPowerOf2()) {
unsigned MaskWidth = CVal.logBase2();
if (MaskWidth == MulWidth)
break; // Recognized
}
}
return nullptr;
case ICmpInst::ICMP_UGT:
// Recognize pattern:
// mulval = mul(zext A, zext B)
// cmp ugt mulval, max
if (ConstantInt *CI = dyn_cast<ConstantInt>(OtherVal)) {
APInt MaxVal = APInt::getMaxValue(MulWidth);
MaxVal = MaxVal.zext(CI->getBitWidth());
if (MaxVal.eq(CI->getValue()))
break; // Recognized
}
return nullptr;
case ICmpInst::ICMP_UGE:
// Recognize pattern:
// mulval = mul(zext A, zext B)
// cmp uge mulval, max+1
if (ConstantInt *CI = dyn_cast<ConstantInt>(OtherVal)) {
APInt MaxVal = APInt::getOneBitSet(CI->getBitWidth(), MulWidth);
if (MaxVal.eq(CI->getValue()))
break; // Recognized
}
return nullptr;
case ICmpInst::ICMP_ULE:
// Recognize pattern:
// mulval = mul(zext A, zext B)
// cmp ule mulval, max
if (ConstantInt *CI = dyn_cast<ConstantInt>(OtherVal)) {
APInt MaxVal = APInt::getMaxValue(MulWidth);
MaxVal = MaxVal.zext(CI->getBitWidth());
if (MaxVal.eq(CI->getValue()))
break; // Recognized
}
return nullptr;
case ICmpInst::ICMP_ULT:
// Recognize pattern:
// mulval = mul(zext A, zext B)
// cmp ule mulval, max + 1
if (ConstantInt *CI = dyn_cast<ConstantInt>(OtherVal)) {
APInt MaxVal = APInt::getOneBitSet(CI->getBitWidth(), MulWidth);
if (MaxVal.eq(CI->getValue()))
break; // Recognized
}
return nullptr;
default:
return nullptr;
}
InstCombiner::BuilderTy *Builder = IC.Builder;
Builder->SetInsertPoint(MulInstr);
Module *M = I.getParent()->getParent()->getParent();
// Replace: mul(zext A, zext B) --> mul.with.overflow(A, B)
Value *MulA = A, *MulB = B;
if (WidthA < MulWidth)
MulA = Builder->CreateZExt(A, MulType);
if (WidthB < MulWidth)
MulB = Builder->CreateZExt(B, MulType);
Value *F =
Intrinsic::getDeclaration(M, Intrinsic::umul_with_overflow, MulType);
CallInst *Call = Builder->CreateCall(F, {MulA, MulB}, "umul");
IC.Worklist.Add(MulInstr);
// If there are uses of mul result other than the comparison, we know that
// they are truncation or binary AND. Change them to use result of
// mul.with.overflow and adjust properly mask/size.
if (MulVal->hasNUsesOrMore(2)) {
Value *Mul = Builder->CreateExtractValue(Call, 0, "umul.value");
for (User *U : MulVal->users()) {
if (U == &I || U == OtherVal)
continue;
if (TruncInst *TI = dyn_cast<TruncInst>(U)) {
if (TI->getType()->getPrimitiveSizeInBits() == MulWidth)
IC.ReplaceInstUsesWith(*TI, Mul);
else
TI->setOperand(0, Mul);
} else if (BinaryOperator *BO = dyn_cast<BinaryOperator>(U)) {
assert(BO->getOpcode() == Instruction::And);
// Replace (mul & mask) --> zext (mul.with.overflow & short_mask)
ConstantInt *CI = cast<ConstantInt>(BO->getOperand(1));
APInt ShortMask = CI->getValue().trunc(MulWidth);
Value *ShortAnd = Builder->CreateAnd(Mul, ShortMask);
Instruction *Zext =
cast<Instruction>(Builder->CreateZExt(ShortAnd, BO->getType()));
IC.Worklist.Add(Zext);
IC.ReplaceInstUsesWith(*BO, Zext);
} else {
llvm_unreachable("Unexpected Binary operation");
}
IC.Worklist.Add(cast<Instruction>(U));
}
}
if (isa<Instruction>(OtherVal))
IC.Worklist.Add(cast<Instruction>(OtherVal));
// The original icmp gets replaced with the overflow value, maybe inverted
// depending on predicate.
bool Inverse = false;
switch (I.getPredicate()) {
case ICmpInst::ICMP_NE:
break;
case ICmpInst::ICMP_EQ:
Inverse = true;
break;
case ICmpInst::ICMP_UGT:
case ICmpInst::ICMP_UGE:
if (I.getOperand(0) == MulVal)
break;
Inverse = true;
break;
case ICmpInst::ICMP_ULT:
case ICmpInst::ICMP_ULE:
if (I.getOperand(1) == MulVal)
break;
Inverse = true;
break;
default:
llvm_unreachable("Unexpected predicate");
}
if (Inverse) {
Value *Res = Builder->CreateExtractValue(Call, 1);
return BinaryOperator::CreateNot(Res);
}
return ExtractValueInst::Create(Call, 1);
}
// DemandedBitsLHSMask - When performing a comparison against a constant,
// it is possible that not all the bits in the LHS are demanded. This helper
// method computes the mask that IS demanded.
static APInt DemandedBitsLHSMask(ICmpInst &I,
unsigned BitWidth, bool isSignCheck) {
if (isSignCheck)
return APInt::getSignBit(BitWidth);
ConstantInt *CI = dyn_cast<ConstantInt>(I.getOperand(1));
if (!CI) return APInt::getAllOnesValue(BitWidth);
const APInt &RHS = CI->getValue();
switch (I.getPredicate()) {
// For a UGT comparison, we don't care about any bits that
// correspond to the trailing ones of the comparand. The value of these
// bits doesn't impact the outcome of the comparison, because any value
// greater than the RHS must differ in a bit higher than these due to carry.
case ICmpInst::ICMP_UGT: {
unsigned trailingOnes = RHS.countTrailingOnes();
APInt lowBitsSet = APInt::getLowBitsSet(BitWidth, trailingOnes);
return ~lowBitsSet;
}
// Similarly, for a ULT comparison, we don't care about the trailing zeros.
// Any value less than the RHS must differ in a higher bit because of carries.
case ICmpInst::ICMP_ULT: {
unsigned trailingZeros = RHS.countTrailingZeros();
APInt lowBitsSet = APInt::getLowBitsSet(BitWidth, trailingZeros);
return ~lowBitsSet;
}
default:
return APInt::getAllOnesValue(BitWidth);
}
}
/// \brief Check if the order of \p Op0 and \p Op1 as operand in an ICmpInst
/// should be swapped.
/// The decision is based on how many times these two operands are reused
/// as subtract operands and their positions in those instructions.
/// The rational is that several architectures use the same instruction for
/// both subtract and cmp, thus it is better if the order of those operands
/// match.
/// \return true if Op0 and Op1 should be swapped.
static bool swapMayExposeCSEOpportunities(const Value * Op0,
const Value * Op1) {
// Filter out pointer value as those cannot appears directly in subtract.
// FIXME: we may want to go through inttoptrs or bitcasts.
if (Op0->getType()->isPointerTy())
return false;
// Count every uses of both Op0 and Op1 in a subtract.
// Each time Op0 is the first operand, count -1: swapping is bad, the
// subtract has already the same layout as the compare.
// Each time Op0 is the second operand, count +1: swapping is good, the
// subtract has a different layout as the compare.
// At the end, if the benefit is greater than 0, Op0 should come second to
// expose more CSE opportunities.
int GlobalSwapBenefits = 0;
for (const User *U : Op0->users()) {
const BinaryOperator *BinOp = dyn_cast<BinaryOperator>(U);
if (!BinOp || BinOp->getOpcode() != Instruction::Sub)
continue;
// If Op0 is the first argument, this is not beneficial to swap the
// arguments.
int LocalSwapBenefits = -1;
unsigned Op1Idx = 1;
if (BinOp->getOperand(Op1Idx) == Op0) {
Op1Idx = 0;
LocalSwapBenefits = 1;
}
if (BinOp->getOperand(Op1Idx) != Op1)
continue;
GlobalSwapBenefits += LocalSwapBenefits;
}
return GlobalSwapBenefits > 0;
}
/// \brief Check that one use is in the same block as the definition and all
/// other uses are in blocks dominated by a given block
///
/// \param DI Definition
/// \param UI Use
/// \param DB Block that must dominate all uses of \p DI outside
/// the parent block
/// \return true when \p UI is the only use of \p DI in the parent block
/// and all other uses of \p DI are in blocks dominated by \p DB.
///
bool InstCombiner::dominatesAllUses(const Instruction *DI,
const Instruction *UI,
const BasicBlock *DB) const {
assert(DI && UI && "Instruction not defined\n");
// ignore incomplete definitions
if (!DI->getParent())
return false;
// DI and UI must be in the same block
if (DI->getParent() != UI->getParent())
return false;
// Protect from self-referencing blocks
if (DI->getParent() == DB)
return false;
// DominatorTree available?
if (!DT)
return false;
for (const User *U : DI->users()) {
auto *Usr = cast<Instruction>(U);
if (Usr != UI && !DT->dominates(DB, Usr->getParent()))
return false;
}
return true;
}
///
/// true when the instruction sequence within a block is select-cmp-br.
///
static bool isChainSelectCmpBranch(const SelectInst *SI) {
const BasicBlock *BB = SI->getParent();
if (!BB)
return false;
auto *BI = dyn_cast_or_null<BranchInst>(BB->getTerminator());
if (!BI || BI->getNumSuccessors() != 2)
return false;
auto *IC = dyn_cast<ICmpInst>(BI->getCondition());
if (!IC || (IC->getOperand(0) != SI && IC->getOperand(1) != SI))
return false;
return true;
}
///
/// \brief True when a select result is replaced by one of its operands
/// in select-icmp sequence. This will eventually result in the elimination
/// of the select.
///
/// \param SI Select instruction
/// \param Icmp Compare instruction
/// \param SIOpd Operand that replaces the select
///
/// Notes:
/// - The replacement is global and requires dominator information
/// - The caller is responsible for the actual replacement
///
/// Example:
///
/// entry:
/// %4 = select i1 %3, %C* %0, %C* null
/// %5 = icmp eq %C* %4, null
/// br i1 %5, label %9, label %7
/// ...
/// ; <label>:7 ; preds = %entry
/// %8 = getelementptr inbounds %C* %4, i64 0, i32 0
/// ...
///
/// can be transformed to
///
/// %5 = icmp eq %C* %0, null
/// %6 = select i1 %3, i1 %5, i1 true
/// br i1 %6, label %9, label %7
/// ...
/// ; <label>:7 ; preds = %entry
/// %8 = getelementptr inbounds %C* %0, i64 0, i32 0 // replace by %0!
///
/// Similar when the first operand of the select is a constant or/and
/// the compare is for not equal rather than equal.
///
/// NOTE: The function is only called when the select and compare constants
/// are equal, the optimization can work only for EQ predicates. This is not a
/// major restriction since a NE compare should be 'normalized' to an equal
/// compare, which usually happens in the combiner and test case
/// select-cmp-br.ll
/// checks for it.
bool InstCombiner::replacedSelectWithOperand(SelectInst *SI,
const ICmpInst *Icmp,
const unsigned SIOpd) {
assert((SIOpd == 1 || SIOpd == 2) && "Invalid select operand!");
if (isChainSelectCmpBranch(SI) && Icmp->getPredicate() == ICmpInst::ICMP_EQ) {
BasicBlock *Succ = SI->getParent()->getTerminator()->getSuccessor(1);
// The check for the unique predecessor is not the best that can be
// done. But it protects efficiently against cases like when SI's
// home block has two successors, Succ and Succ1, and Succ1 predecessor
// of Succ. Then SI can't be replaced by SIOpd because the use that gets
// replaced can be reached on either path. So the uniqueness check
// guarantees that the path all uses of SI (outside SI's parent) are on
// is disjoint from all other paths out of SI. But that information
// is more expensive to compute, and the trade-off here is in favor
// of compile-time.
if (Succ->getUniquePredecessor() && dominatesAllUses(SI, Icmp, Succ)) {
NumSel++;
SI->replaceUsesOutsideBlock(SI->getOperand(SIOpd), SI->getParent());
return true;
}
}
return false;
}
Instruction *InstCombiner::visitICmpInst(ICmpInst &I) {
bool Changed = false;
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
unsigned Op0Cplxity = getComplexity(Op0);
unsigned Op1Cplxity = getComplexity(Op1);
/// Orders the operands of the compare so that they are listed from most
/// complex to least complex. This puts constants before unary operators,
/// before binary operators.
if (Op0Cplxity < Op1Cplxity ||
(Op0Cplxity == Op1Cplxity &&
swapMayExposeCSEOpportunities(Op0, Op1))) {
I.swapOperands();
std::swap(Op0, Op1);
Changed = true;
}
if (Value *V =
SimplifyICmpInst(I.getPredicate(), Op0, Op1, DL, TLI, DT, AC, &I))
return ReplaceInstUsesWith(I, V);
// comparing -val or val with non-zero is the same as just comparing val
// ie, abs(val) != 0 -> val != 0
if (I.getPredicate() == ICmpInst::ICMP_NE && match(Op1, m_Zero()))
{
Value *Cond, *SelectTrue, *SelectFalse;
if (match(Op0, m_Select(m_Value(Cond), m_Value(SelectTrue),
m_Value(SelectFalse)))) {
if (Value *V = dyn_castNegVal(SelectTrue)) {
if (V == SelectFalse)
return CmpInst::Create(Instruction::ICmp, I.getPredicate(), V, Op1);
}
else if (Value *V = dyn_castNegVal(SelectFalse)) {
if (V == SelectTrue)
return CmpInst::Create(Instruction::ICmp, I.getPredicate(), V, Op1);
}
}
}
Type *Ty = Op0->getType();
// icmp's with boolean values can always be turned into bitwise operations
if (Ty->isIntegerTy(1)) {
switch (I.getPredicate()) {
default: llvm_unreachable("Invalid icmp instruction!");
case ICmpInst::ICMP_EQ: { // icmp eq i1 A, B -> ~(A^B)
Value *Xor = Builder->CreateXor(Op0, Op1, I.getName()+"tmp");
return BinaryOperator::CreateNot(Xor);
}
case ICmpInst::ICMP_NE: // icmp eq i1 A, B -> A^B
return BinaryOperator::CreateXor(Op0, Op1);
case ICmpInst::ICMP_UGT:
std::swap(Op0, Op1); // Change icmp ugt -> icmp ult
LLVM_FALLTHROUGH; // HLSL CHANGE
case ICmpInst::ICMP_ULT:{ // icmp ult i1 A, B -> ~A & B
Value *Not = Builder->CreateNot(Op0, I.getName()+"tmp");
return BinaryOperator::CreateAnd(Not, Op1);
}
case ICmpInst::ICMP_SGT:
std::swap(Op0, Op1); // Change icmp sgt -> icmp slt
LLVM_FALLTHROUGH; // HLSL CHANGE
case ICmpInst::ICMP_SLT: { // icmp slt i1 A, B -> A & ~B
Value *Not = Builder->CreateNot(Op1, I.getName()+"tmp");
return BinaryOperator::CreateAnd(Not, Op0);
}
case ICmpInst::ICMP_UGE:
std::swap(Op0, Op1); // Change icmp uge -> icmp ule
LLVM_FALLTHROUGH; // HLSL CHANGE
case ICmpInst::ICMP_ULE: { // icmp ule i1 A, B -> ~A | B
Value *Not = Builder->CreateNot(Op0, I.getName()+"tmp");
return BinaryOperator::CreateOr(Not, Op1);
}
case ICmpInst::ICMP_SGE:
std::swap(Op0, Op1); // Change icmp sge -> icmp sle
LLVM_FALLTHROUGH; // HLSL CHANGE
case ICmpInst::ICMP_SLE: { // icmp sle i1 A, B -> A | ~B
Value *Not = Builder->CreateNot(Op1, I.getName()+"tmp");
return BinaryOperator::CreateOr(Not, Op0);
}
}
}
unsigned BitWidth = 0;
if (Ty->isIntOrIntVectorTy())
BitWidth = Ty->getScalarSizeInBits();
else // Get pointer size.
BitWidth = DL.getTypeSizeInBits(Ty->getScalarType());
bool isSignBit = false;
// See if we are doing a comparison with a constant.
if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
Value *A = nullptr, *B = nullptr;
// Match the following pattern, which is a common idiom when writing
// overflow-safe integer arithmetic function. The source performs an
// addition in wider type, and explicitly checks for overflow using
// comparisons against INT_MIN and INT_MAX. Simplify this by using the
// sadd_with_overflow intrinsic.
//
// TODO: This could probably be generalized to handle other overflow-safe
// operations if we worked out the formulas to compute the appropriate
// magic constants.
//
// sum = a + b
// if (sum+128 >u 255) ... -> llvm.sadd.with.overflow.i8
{
ConstantInt *CI2; // I = icmp ugt (add (add A, B), CI2), CI
if (I.getPredicate() == ICmpInst::ICMP_UGT &&
match(Op0, m_Add(m_Add(m_Value(A), m_Value(B)), m_ConstantInt(CI2))))
if (Instruction *Res = ProcessUGT_ADDCST_ADD(I, A, B, CI2, CI, *this))
return Res;
}
// The following transforms are only 'worth it' if the only user of the
// subtraction is the icmp.
if (Op0->hasOneUse()) {
// (icmp ne/eq (sub A B) 0) -> (icmp ne/eq A, B)
if (I.isEquality() && CI->isZero() &&
match(Op0, m_Sub(m_Value(A), m_Value(B))))
return new ICmpInst(I.getPredicate(), A, B);
// (icmp sgt (sub nsw A B), -1) -> (icmp sge A, B)
if (I.getPredicate() == ICmpInst::ICMP_SGT && CI->isAllOnesValue() &&
match(Op0, m_NSWSub(m_Value(A), m_Value(B))))
return new ICmpInst(ICmpInst::ICMP_SGE, A, B);
// (icmp sgt (sub nsw A B), 0) -> (icmp sgt A, B)
if (I.getPredicate() == ICmpInst::ICMP_SGT && CI->isZero() &&
match(Op0, m_NSWSub(m_Value(A), m_Value(B))))
return new ICmpInst(ICmpInst::ICMP_SGT, A, B);
// (icmp slt (sub nsw A B), 0) -> (icmp slt A, B)
if (I.getPredicate() == ICmpInst::ICMP_SLT && CI->isZero() &&
match(Op0, m_NSWSub(m_Value(A), m_Value(B))))
return new ICmpInst(ICmpInst::ICMP_SLT, A, B);
// (icmp slt (sub nsw A B), 1) -> (icmp sle A, B)
if (I.getPredicate() == ICmpInst::ICMP_SLT && CI->isOne() &&
match(Op0, m_NSWSub(m_Value(A), m_Value(B))))
return new ICmpInst(ICmpInst::ICMP_SLE, A, B);
}
// If we have an icmp le or icmp ge instruction, turn it into the
// appropriate icmp lt or icmp gt instruction. This allows us to rely on
// them being folded in the code below. The SimplifyICmpInst code has
// already handled the edge cases for us, so we just assert on them.
switch (I.getPredicate()) {
default: break;
case ICmpInst::ICMP_ULE:
assert(!CI->isMaxValue(false)); // A <=u MAX -> TRUE
return new ICmpInst(ICmpInst::ICMP_ULT, Op0,
Builder->getInt(CI->getValue()+1));
case ICmpInst::ICMP_SLE:
assert(!CI->isMaxValue(true)); // A <=s MAX -> TRUE
return new ICmpInst(ICmpInst::ICMP_SLT, Op0,
Builder->getInt(CI->getValue()+1));
case ICmpInst::ICMP_UGE:
assert(!CI->isMinValue(false)); // A >=u MIN -> TRUE
return new ICmpInst(ICmpInst::ICMP_UGT, Op0,
Builder->getInt(CI->getValue()-1));
case ICmpInst::ICMP_SGE:
assert(!CI->isMinValue(true)); // A >=s MIN -> TRUE
return new ICmpInst(ICmpInst::ICMP_SGT, Op0,
Builder->getInt(CI->getValue()-1));
}
if (I.isEquality()) {
ConstantInt *CI2;
if (match(Op0, m_AShr(m_ConstantInt(CI2), m_Value(A))) ||
match(Op0, m_LShr(m_ConstantInt(CI2), m_Value(A)))) {
// (icmp eq/ne (ashr/lshr const2, A), const1)
if (Instruction *Inst = FoldICmpCstShrCst(I, Op0, A, CI, CI2))
return Inst;
}
if (match(Op0, m_Shl(m_ConstantInt(CI2), m_Value(A)))) {
// (icmp eq/ne (shl const2, A), const1)
if (Instruction *Inst = FoldICmpCstShlCst(I, Op0, A, CI, CI2))
return Inst;
}
}
// If this comparison is a normal comparison, it demands all
// bits, if it is a sign bit comparison, it only demands the sign bit.
bool UnusedBit;
isSignBit = isSignBitCheck(I.getPredicate(), CI, UnusedBit);
}
// See if we can fold the comparison based on range information we can get
// by checking whether bits are known to be zero or one in the input.
if (BitWidth != 0) {
APInt Op0KnownZero(BitWidth, 0), Op0KnownOne(BitWidth, 0);
APInt Op1KnownZero(BitWidth, 0), Op1KnownOne(BitWidth, 0);
if (SimplifyDemandedBits(I.getOperandUse(0),
DemandedBitsLHSMask(I, BitWidth, isSignBit),
Op0KnownZero, Op0KnownOne, 0))
return &I;
if (SimplifyDemandedBits(I.getOperandUse(1),
APInt::getAllOnesValue(BitWidth), Op1KnownZero,
Op1KnownOne, 0))
return &I;
// Given the known and unknown bits, compute a range that the LHS could be
// in. Compute the Min, Max and RHS values based on the known bits. For the
// EQ and NE we use unsigned values.
APInt Op0Min(BitWidth, 0), Op0Max(BitWidth, 0);
APInt Op1Min(BitWidth, 0), Op1Max(BitWidth, 0);
if (I.isSigned()) {
ComputeSignedMinMaxValuesFromKnownBits(Op0KnownZero, Op0KnownOne,
Op0Min, Op0Max);
ComputeSignedMinMaxValuesFromKnownBits(Op1KnownZero, Op1KnownOne,
Op1Min, Op1Max);
} else {
ComputeUnsignedMinMaxValuesFromKnownBits(Op0KnownZero, Op0KnownOne,
Op0Min, Op0Max);
ComputeUnsignedMinMaxValuesFromKnownBits(Op1KnownZero, Op1KnownOne,
Op1Min, Op1Max);
}
// If Min and Max are known to be the same, then SimplifyDemandedBits
// figured out that the LHS is a constant. Just constant fold this now so
// that code below can assume that Min != Max.
if (!isa<Constant>(Op0) && Op0Min == Op0Max)
return new ICmpInst(I.getPredicate(),
ConstantInt::get(Op0->getType(), Op0Min), Op1);
if (!isa<Constant>(Op1) && Op1Min == Op1Max)
return new ICmpInst(I.getPredicate(), Op0,
ConstantInt::get(Op1->getType(), Op1Min));
// Based on the range information we know about the LHS, see if we can
// simplify this comparison. For example, (x&4) < 8 is always true.
switch (I.getPredicate()) {
default: llvm_unreachable("Unknown icmp opcode!");
case ICmpInst::ICMP_EQ: {
if (Op0Max.ult(Op1Min) || Op0Min.ugt(Op1Max))
return ReplaceInstUsesWith(I, ConstantInt::getFalse(I.getType()));
// If all bits are known zero except for one, then we know at most one
// bit is set. If the comparison is against zero, then this is a check
// to see if *that* bit is set.
APInt Op0KnownZeroInverted = ~Op0KnownZero;
if (~Op1KnownZero == 0) {
// If the LHS is an AND with the same constant, look through it.
Value *LHS = nullptr;
ConstantInt *LHSC = nullptr;
if (!match(Op0, m_And(m_Value(LHS), m_ConstantInt(LHSC))) ||
LHSC->getValue() != Op0KnownZeroInverted)
LHS = Op0;
// If the LHS is 1 << x, and we know the result is a power of 2 like 8,
// then turn "((1 << x)&8) == 0" into "x != 3".
// or turn "((1 << x)&7) == 0" into "x > 2".
Value *X = nullptr;
if (match(LHS, m_Shl(m_One(), m_Value(X)))) {
APInt ValToCheck = Op0KnownZeroInverted;
if (ValToCheck.isPowerOf2()) {
unsigned CmpVal = ValToCheck.countTrailingZeros();
return new ICmpInst(ICmpInst::ICMP_NE, X,
ConstantInt::get(X->getType(), CmpVal));
} else if ((++ValToCheck).isPowerOf2()) {
unsigned CmpVal = ValToCheck.countTrailingZeros() - 1;
return new ICmpInst(ICmpInst::ICMP_UGT, X,
ConstantInt::get(X->getType(), CmpVal));
}
}
// If the LHS is 8 >>u x, and we know the result is a power of 2 like 1,
// then turn "((8 >>u x)&1) == 0" into "x != 3".
const APInt *CI;
if (Op0KnownZeroInverted == 1 &&
match(LHS, m_LShr(m_Power2(CI), m_Value(X))))
return new ICmpInst(ICmpInst::ICMP_NE, X,
ConstantInt::get(X->getType(),
CI->countTrailingZeros()));
}
break;
}
case ICmpInst::ICMP_NE: {
if (Op0Max.ult(Op1Min) || Op0Min.ugt(Op1Max))
return ReplaceInstUsesWith(I, ConstantInt::getTrue(I.getType()));
// If all bits are known zero except for one, then we know at most one
// bit is set. If the comparison is against zero, then this is a check
// to see if *that* bit is set.
APInt Op0KnownZeroInverted = ~Op0KnownZero;
if (~Op1KnownZero == 0) {
// If the LHS is an AND with the same constant, look through it.
Value *LHS = nullptr;
ConstantInt *LHSC = nullptr;
if (!match(Op0, m_And(m_Value(LHS), m_ConstantInt(LHSC))) ||
LHSC->getValue() != Op0KnownZeroInverted)
LHS = Op0;
// If the LHS is 1 << x, and we know the result is a power of 2 like 8,
// then turn "((1 << x)&8) != 0" into "x == 3".
// or turn "((1 << x)&7) != 0" into "x < 3".
Value *X = nullptr;
if (match(LHS, m_Shl(m_One(), m_Value(X)))) {
APInt ValToCheck = Op0KnownZeroInverted;
if (ValToCheck.isPowerOf2()) {
unsigned CmpVal = ValToCheck.countTrailingZeros();
return new ICmpInst(ICmpInst::ICMP_EQ, X,
ConstantInt::get(X->getType(), CmpVal));
} else if ((++ValToCheck).isPowerOf2()) {
unsigned CmpVal = ValToCheck.countTrailingZeros();
return new ICmpInst(ICmpInst::ICMP_ULT, X,
ConstantInt::get(X->getType(), CmpVal));
}
}
// If the LHS is 8 >>u x, and we know the result is a power of 2 like 1,
// then turn "((8 >>u x)&1) != 0" into "x == 3".
const APInt *CI;
if (Op0KnownZeroInverted == 1 &&
match(LHS, m_LShr(m_Power2(CI), m_Value(X))))
return new ICmpInst(ICmpInst::ICMP_EQ, X,
ConstantInt::get(X->getType(),
CI->countTrailingZeros()));
}
break;
}
case ICmpInst::ICMP_ULT:
if (Op0Max.ult(Op1Min)) // A <u B -> true if max(A) < min(B)
return ReplaceInstUsesWith(I, ConstantInt::getTrue(I.getType()));
if (Op0Min.uge(Op1Max)) // A <u B -> false if min(A) >= max(B)
return ReplaceInstUsesWith(I, ConstantInt::getFalse(I.getType()));
if (Op1Min == Op0Max) // A <u B -> A != B if max(A) == min(B)
return new ICmpInst(ICmpInst::ICMP_NE, Op0, Op1);
if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
if (Op1Max == Op0Min+1) // A <u C -> A == C-1 if min(A)+1 == C
return new ICmpInst(ICmpInst::ICMP_EQ, Op0,
Builder->getInt(CI->getValue()-1));
// (x <u 2147483648) -> (x >s -1) -> true if sign bit clear
if (CI->isMinValue(true))
return new ICmpInst(ICmpInst::ICMP_SGT, Op0,
Constant::getAllOnesValue(Op0->getType()));
}
break;
case ICmpInst::ICMP_UGT:
if (Op0Min.ugt(Op1Max)) // A >u B -> true if min(A) > max(B)
return ReplaceInstUsesWith(I, ConstantInt::getTrue(I.getType()));
if (Op0Max.ule(Op1Min)) // A >u B -> false if max(A) <= max(B)
return ReplaceInstUsesWith(I, ConstantInt::getFalse(I.getType()));
if (Op1Max == Op0Min) // A >u B -> A != B if min(A) == max(B)
return new ICmpInst(ICmpInst::ICMP_NE, Op0, Op1);
if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
if (Op1Min == Op0Max-1) // A >u C -> A == C+1 if max(a)-1 == C
return new ICmpInst(ICmpInst::ICMP_EQ, Op0,
Builder->getInt(CI->getValue()+1));
// (x >u 2147483647) -> (x <s 0) -> true if sign bit set
if (CI->isMaxValue(true))
return new ICmpInst(ICmpInst::ICMP_SLT, Op0,
Constant::getNullValue(Op0->getType()));
}
break;
case ICmpInst::ICMP_SLT:
if (Op0Max.slt(Op1Min)) // A <s B -> true if max(A) < min(C)
return ReplaceInstUsesWith(I, ConstantInt::getTrue(I.getType()));
if (Op0Min.sge(Op1Max)) // A <s B -> false if min(A) >= max(C)
return ReplaceInstUsesWith(I, ConstantInt::getFalse(I.getType()));
if (Op1Min == Op0Max) // A <s B -> A != B if max(A) == min(B)
return new ICmpInst(ICmpInst::ICMP_NE, Op0, Op1);
if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
if (Op1Max == Op0Min+1) // A <s C -> A == C-1 if min(A)+1 == C
return new ICmpInst(ICmpInst::ICMP_EQ, Op0,
Builder->getInt(CI->getValue()-1));
}
break;
case ICmpInst::ICMP_SGT:
if (Op0Min.sgt(Op1Max)) // A >s B -> true if min(A) > max(B)
return ReplaceInstUsesWith(I, ConstantInt::getTrue(I.getType()));
if (Op0Max.sle(Op1Min)) // A >s B -> false if max(A) <= min(B)
return ReplaceInstUsesWith(I, ConstantInt::getFalse(I.getType()));
if (Op1Max == Op0Min) // A >s B -> A != B if min(A) == max(B)
return new ICmpInst(ICmpInst::ICMP_NE, Op0, Op1);
if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
if (Op1Min == Op0Max-1) // A >s C -> A == C+1 if max(A)-1 == C
return new ICmpInst(ICmpInst::ICMP_EQ, Op0,
Builder->getInt(CI->getValue()+1));
}
break;
case ICmpInst::ICMP_SGE:
assert(!isa<ConstantInt>(Op1) && "ICMP_SGE with ConstantInt not folded!");
if (Op0Min.sge(Op1Max)) // A >=s B -> true if min(A) >= max(B)
return ReplaceInstUsesWith(I, ConstantInt::getTrue(I.getType()));
if (Op0Max.slt(Op1Min)) // A >=s B -> false if max(A) < min(B)
return ReplaceInstUsesWith(I, ConstantInt::getFalse(I.getType()));
break;
case ICmpInst::ICMP_SLE:
assert(!isa<ConstantInt>(Op1) && "ICMP_SLE with ConstantInt not folded!");
if (Op0Max.sle(Op1Min)) // A <=s B -> true if max(A) <= min(B)
return ReplaceInstUsesWith(I, ConstantInt::getTrue(I.getType()));
if (Op0Min.sgt(Op1Max)) // A <=s B -> false if min(A) > max(B)
return ReplaceInstUsesWith(I, ConstantInt::getFalse(I.getType()));
break;
case ICmpInst::ICMP_UGE:
assert(!isa<ConstantInt>(Op1) && "ICMP_UGE with ConstantInt not folded!");
if (Op0Min.uge(Op1Max)) // A >=u B -> true if min(A) >= max(B)
return ReplaceInstUsesWith(I, ConstantInt::getTrue(I.getType()));
if (Op0Max.ult(Op1Min)) // A >=u B -> false if max(A) < min(B)
return ReplaceInstUsesWith(I, ConstantInt::getFalse(I.getType()));
break;
case ICmpInst::ICMP_ULE:
assert(!isa<ConstantInt>(Op1) && "ICMP_ULE with ConstantInt not folded!");
if (Op0Max.ule(Op1Min)) // A <=u B -> true if max(A) <= min(B)
return ReplaceInstUsesWith(I, ConstantInt::getTrue(I.getType()));
if (Op0Min.ugt(Op1Max)) // A <=u B -> false if min(A) > max(B)
return ReplaceInstUsesWith(I, ConstantInt::getFalse(I.getType()));
break;
}
// Turn a signed comparison into an unsigned one if both operands
// are known to have the same sign.
if (I.isSigned() &&
((Op0KnownZero.isNegative() && Op1KnownZero.isNegative()) ||
(Op0KnownOne.isNegative() && Op1KnownOne.isNegative())))
return new ICmpInst(I.getUnsignedPredicate(), Op0, Op1);
}
// Test if the ICmpInst instruction is used exclusively by a select as
// part of a minimum or maximum operation. If so, refrain from doing
// any other folding. This helps out other analyses which understand
// non-obfuscated minimum and maximum idioms, such as ScalarEvolution
// and CodeGen. And in this case, at least one of the comparison
// operands has at least one user besides the compare (the select),
// which would often largely negate the benefit of folding anyway.
if (I.hasOneUse())
if (SelectInst *SI = dyn_cast<SelectInst>(*I.user_begin()))
if ((SI->getOperand(1) == Op0 && SI->getOperand(2) == Op1) ||
(SI->getOperand(2) == Op0 && SI->getOperand(1) == Op1))
return nullptr;
// See if we are doing a comparison between a constant and an instruction that
// can be folded into the comparison.
if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
// Since the RHS is a ConstantInt (CI), if the left hand side is an
// instruction, see if that instruction also has constants so that the
// instruction can be folded into the icmp
if (Instruction *LHSI = dyn_cast<Instruction>(Op0))
if (Instruction *Res = visitICmpInstWithInstAndIntCst(I, LHSI, CI))
return Res;
}
// Handle icmp with constant (but not simple integer constant) RHS
if (Constant *RHSC = dyn_cast<Constant>(Op1)) {
if (Instruction *LHSI = dyn_cast<Instruction>(Op0))
switch (LHSI->getOpcode()) {
case Instruction::GetElementPtr:
// icmp pred GEP (P, int 0, int 0, int 0), null -> icmp pred P, null
if (RHSC->isNullValue() &&
cast<GetElementPtrInst>(LHSI)->hasAllZeroIndices())
return new ICmpInst(I.getPredicate(), LHSI->getOperand(0),
Constant::getNullValue(LHSI->getOperand(0)->getType()));
break;
case Instruction::PHI:
// Only fold icmp into the PHI if the phi and icmp are in the same
// block. If in the same block, we're encouraging jump threading. If
// not, we are just pessimizing the code by making an i1 phi.
if (LHSI->getParent() == I.getParent())
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
break;
case Instruction::Select: {
// If either operand of the select is a constant, we can fold the
// comparison into the select arms, which will cause one to be
// constant folded and the select turned into a bitwise or.
Value *Op1 = nullptr, *Op2 = nullptr;
ConstantInt *CI = 0;
if (Constant *C = dyn_cast<Constant>(LHSI->getOperand(1))) {
Op1 = ConstantExpr::getICmp(I.getPredicate(), C, RHSC);
CI = dyn_cast<ConstantInt>(Op1);
}
if (Constant *C = dyn_cast<Constant>(LHSI->getOperand(2))) {
Op2 = ConstantExpr::getICmp(I.getPredicate(), C, RHSC);
CI = dyn_cast<ConstantInt>(Op2);
}
// We only want to perform this transformation if it will not lead to
// additional code. This is true if either both sides of the select
// fold to a constant (in which case the icmp is replaced with a select
// which will usually simplify) or this is the only user of the
// select (in which case we are trading a select+icmp for a simpler
// select+icmp) or all uses of the select can be replaced based on
// dominance information ("Global cases").
bool Transform = false;
if (Op1 && Op2)
Transform = true;
else if (Op1 || Op2) {
// Local case
if (LHSI->hasOneUse())
Transform = true;
// Global cases
else if (CI && !CI->isZero())
// When Op1 is constant try replacing select with second operand.
// Otherwise Op2 is constant and try replacing select with first
// operand.
Transform = replacedSelectWithOperand(cast<SelectInst>(LHSI), &I,
Op1 ? 2 : 1);
}
if (Transform) {
if (!Op1)
Op1 = Builder->CreateICmp(I.getPredicate(), LHSI->getOperand(1),
RHSC, I.getName());
if (!Op2)
Op2 = Builder->CreateICmp(I.getPredicate(), LHSI->getOperand(2),
RHSC, I.getName());
return SelectInst::Create(LHSI->getOperand(0), Op1, Op2);
}
break;
}
case Instruction::IntToPtr:
// icmp pred inttoptr(X), null -> icmp pred X, 0
if (RHSC->isNullValue() &&
DL.getIntPtrType(RHSC->getType()) == LHSI->getOperand(0)->getType())
return new ICmpInst(I.getPredicate(), LHSI->getOperand(0),
Constant::getNullValue(LHSI->getOperand(0)->getType()));
break;
case Instruction::Load:
// Try to optimize things like "A[i] > 4" to index computations.
if (GetElementPtrInst *GEP =
dyn_cast<GetElementPtrInst>(LHSI->getOperand(0))) {
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(GEP->getOperand(0)))
if (GV->isConstant() && GV->hasDefinitiveInitializer() &&
!cast<LoadInst>(LHSI)->isVolatile())
if (Instruction *Res = FoldCmpLoadFromIndexedGlobal(GEP, GV, I))
return Res;
}
break;
}
}
// If we can optimize a 'icmp GEP, P' or 'icmp P, GEP', do so now.
if (GEPOperator *GEP = dyn_cast<GEPOperator>(Op0))
if (Instruction *NI = FoldGEPICmp(GEP, Op1, I.getPredicate(), I))
return NI;
if (GEPOperator *GEP = dyn_cast<GEPOperator>(Op1))
if (Instruction *NI = FoldGEPICmp(GEP, Op0,
ICmpInst::getSwappedPredicate(I.getPredicate()), I))
return NI;
// Test to see if the operands of the icmp are casted versions of other
// values. If the ptr->ptr cast can be stripped off both arguments, we do so
// now.
if (BitCastInst *CI = dyn_cast<BitCastInst>(Op0)) {
if (Op0->getType()->isPointerTy() &&
(isa<Constant>(Op1) || isa<BitCastInst>(Op1))) {
// We keep moving the cast from the left operand over to the right
// operand, where it can often be eliminated completely.
Op0 = CI->getOperand(0);
// If operand #1 is a bitcast instruction, it must also be a ptr->ptr cast
// so eliminate it as well.
if (BitCastInst *CI2 = dyn_cast<BitCastInst>(Op1))
Op1 = CI2->getOperand(0);
// If Op1 is a constant, we can fold the cast into the constant.
if (Op0->getType() != Op1->getType()) {
if (Constant *Op1C = dyn_cast<Constant>(Op1)) {
Op1 = ConstantExpr::getBitCast(Op1C, Op0->getType());
} else {
// Otherwise, cast the RHS right before the icmp
Op1 = Builder->CreateBitCast(Op1, Op0->getType());
}
}
return new ICmpInst(I.getPredicate(), Op0, Op1);
}
}
if (isa<CastInst>(Op0)) {
// Handle the special case of: icmp (cast bool to X), <cst>
// This comes up when you have code like
// int X = A < B;
// if (X) ...
// For generality, we handle any zero-extension of any operand comparison
// with a constant or another cast from the same type.
if (isa<Constant>(Op1) || isa<CastInst>(Op1))
if (Instruction *R = visitICmpInstWithCastAndCast(I))
return R;
}
// Special logic for binary operators.
BinaryOperator *BO0 = dyn_cast<BinaryOperator>(Op0);
BinaryOperator *BO1 = dyn_cast<BinaryOperator>(Op1);
if (BO0 || BO1) {
CmpInst::Predicate Pred = I.getPredicate();
bool NoOp0WrapProblem = false, NoOp1WrapProblem = false;
if (BO0 && isa<OverflowingBinaryOperator>(BO0))
NoOp0WrapProblem = ICmpInst::isEquality(Pred) ||
(CmpInst::isUnsigned(Pred) && BO0->hasNoUnsignedWrap()) ||
(CmpInst::isSigned(Pred) && BO0->hasNoSignedWrap());
if (BO1 && isa<OverflowingBinaryOperator>(BO1))
NoOp1WrapProblem = ICmpInst::isEquality(Pred) ||
(CmpInst::isUnsigned(Pred) && BO1->hasNoUnsignedWrap()) ||
(CmpInst::isSigned(Pred) && BO1->hasNoSignedWrap());
// Analyze the case when either Op0 or Op1 is an add instruction.
// Op0 = A + B (or A and B are null); Op1 = C + D (or C and D are null).
Value *A = nullptr, *B = nullptr, *C = nullptr, *D = nullptr;
if (BO0 && BO0->getOpcode() == Instruction::Add)
A = BO0->getOperand(0), B = BO0->getOperand(1);
if (BO1 && BO1->getOpcode() == Instruction::Add)
C = BO1->getOperand(0), D = BO1->getOperand(1);
// icmp (X+cst) < 0 --> X < -cst
if (NoOp0WrapProblem && ICmpInst::isSigned(Pred) && match(Op1, m_Zero()))
if (ConstantInt *RHSC = dyn_cast_or_null<ConstantInt>(B))
if (!RHSC->isMinValue(/*isSigned=*/true))
return new ICmpInst(Pred, A, ConstantExpr::getNeg(RHSC));
// icmp (X+Y), X -> icmp Y, 0 for equalities or if there is no overflow.
if ((A == Op1 || B == Op1) && NoOp0WrapProblem)
return new ICmpInst(Pred, A == Op1 ? B : A,
Constant::getNullValue(Op1->getType()));
// icmp X, (X+Y) -> icmp 0, Y for equalities or if there is no overflow.
if ((C == Op0 || D == Op0) && NoOp1WrapProblem)
return new ICmpInst(Pred, Constant::getNullValue(Op0->getType()),
C == Op0 ? D : C);
// icmp (X+Y), (X+Z) -> icmp Y, Z for equalities or if there is no overflow.
if (A && C && (A == C || A == D || B == C || B == D) &&
NoOp0WrapProblem && NoOp1WrapProblem &&
// Try not to increase register pressure.
BO0->hasOneUse() && BO1->hasOneUse()) {
// Determine Y and Z in the form icmp (X+Y), (X+Z).
Value *Y, *Z;
if (A == C) {
// C + B == C + D -> B == D
Y = B;
Z = D;
} else if (A == D) {
// D + B == C + D -> B == C
Y = B;
Z = C;
} else if (B == C) {
// A + C == C + D -> A == D
Y = A;
Z = D;
} else {
assert(B == D);
// A + D == C + D -> A == C
Y = A;
Z = C;
}
return new ICmpInst(Pred, Y, Z);
}
// icmp slt (X + -1), Y -> icmp sle X, Y
if (A && NoOp0WrapProblem && Pred == CmpInst::ICMP_SLT &&
match(B, m_AllOnes()))
return new ICmpInst(CmpInst::ICMP_SLE, A, Op1);
// icmp sge (X + -1), Y -> icmp sgt X, Y
if (A && NoOp0WrapProblem && Pred == CmpInst::ICMP_SGE &&
match(B, m_AllOnes()))
return new ICmpInst(CmpInst::ICMP_SGT, A, Op1);
// icmp sle (X + 1), Y -> icmp slt X, Y
if (A && NoOp0WrapProblem && Pred == CmpInst::ICMP_SLE &&
match(B, m_One()))
return new ICmpInst(CmpInst::ICMP_SLT, A, Op1);
// icmp sgt (X + 1), Y -> icmp sge X, Y
if (A && NoOp0WrapProblem && Pred == CmpInst::ICMP_SGT &&
match(B, m_One()))
return new ICmpInst(CmpInst::ICMP_SGE, A, Op1);
// if C1 has greater magnitude than C2:
// icmp (X + C1), (Y + C2) -> icmp (X + C3), Y
// s.t. C3 = C1 - C2
//
// if C2 has greater magnitude than C1:
// icmp (X + C1), (Y + C2) -> icmp X, (Y + C3)
// s.t. C3 = C2 - C1
if (A && C && NoOp0WrapProblem && NoOp1WrapProblem &&
(BO0->hasOneUse() || BO1->hasOneUse()) && !I.isUnsigned())
if (ConstantInt *C1 = dyn_cast<ConstantInt>(B))
if (ConstantInt *C2 = dyn_cast<ConstantInt>(D)) {
const APInt &AP1 = C1->getValue();
const APInt &AP2 = C2->getValue();
if (AP1.isNegative() == AP2.isNegative()) {
APInt AP1Abs = C1->getValue().abs();
APInt AP2Abs = C2->getValue().abs();
if (AP1Abs.uge(AP2Abs)) {
ConstantInt *C3 = Builder->getInt(AP1 - AP2);
Value *NewAdd = Builder->CreateNSWAdd(A, C3);
return new ICmpInst(Pred, NewAdd, C);
} else {
ConstantInt *C3 = Builder->getInt(AP2 - AP1);
Value *NewAdd = Builder->CreateNSWAdd(C, C3);
return new ICmpInst(Pred, A, NewAdd);
}
}
}
// Analyze the case when either Op0 or Op1 is a sub instruction.
// Op0 = A - B (or A and B are null); Op1 = C - D (or C and D are null).
A = nullptr; B = nullptr; C = nullptr; D = nullptr;
if (BO0 && BO0->getOpcode() == Instruction::Sub)
A = BO0->getOperand(0), B = BO0->getOperand(1);
if (BO1 && BO1->getOpcode() == Instruction::Sub)
C = BO1->getOperand(0), D = BO1->getOperand(1);
// icmp (X-Y), X -> icmp 0, Y for equalities or if there is no overflow.
if (A == Op1 && NoOp0WrapProblem)
return new ICmpInst(Pred, Constant::getNullValue(Op1->getType()), B);
// icmp X, (X-Y) -> icmp Y, 0 for equalities or if there is no overflow.
if (C == Op0 && NoOp1WrapProblem)
return new ICmpInst(Pred, D, Constant::getNullValue(Op0->getType()));
// icmp (Y-X), (Z-X) -> icmp Y, Z for equalities or if there is no overflow.
if (B && D && B == D && NoOp0WrapProblem && NoOp1WrapProblem &&
// Try not to increase register pressure.
BO0->hasOneUse() && BO1->hasOneUse())
return new ICmpInst(Pred, A, C);
// icmp (X-Y), (X-Z) -> icmp Z, Y for equalities or if there is no overflow.
if (A && C && A == C && NoOp0WrapProblem && NoOp1WrapProblem &&
// Try not to increase register pressure.
BO0->hasOneUse() && BO1->hasOneUse())
return new ICmpInst(Pred, D, B);
// icmp (0-X) < cst --> x > -cst
if (NoOp0WrapProblem && ICmpInst::isSigned(Pred)) {
Value *X;
if (match(BO0, m_Neg(m_Value(X))))
if (ConstantInt *RHSC = dyn_cast<ConstantInt>(Op1))
if (!RHSC->isMinValue(/*isSigned=*/true))
return new ICmpInst(I.getSwappedPredicate(), X,
ConstantExpr::getNeg(RHSC));
}
BinaryOperator *SRem = nullptr;
// icmp (srem X, Y), Y
if (BO0 && BO0->getOpcode() == Instruction::SRem &&
Op1 == BO0->getOperand(1))
SRem = BO0;
// icmp Y, (srem X, Y)
else if (BO1 && BO1->getOpcode() == Instruction::SRem &&
Op0 == BO1->getOperand(1))
SRem = BO1;
if (SRem) {
// We don't check hasOneUse to avoid increasing register pressure because
// the value we use is the same value this instruction was already using.
switch (SRem == BO0 ? ICmpInst::getSwappedPredicate(Pred) : Pred) {
default: break;
case ICmpInst::ICMP_EQ:
return ReplaceInstUsesWith(I, ConstantInt::getFalse(I.getType()));
case ICmpInst::ICMP_NE:
return ReplaceInstUsesWith(I, ConstantInt::getTrue(I.getType()));
case ICmpInst::ICMP_SGT:
case ICmpInst::ICMP_SGE:
return new ICmpInst(ICmpInst::ICMP_SGT, SRem->getOperand(1),
Constant::getAllOnesValue(SRem->getType()));
case ICmpInst::ICMP_SLT:
case ICmpInst::ICMP_SLE:
return new ICmpInst(ICmpInst::ICMP_SLT, SRem->getOperand(1),
Constant::getNullValue(SRem->getType()));
}
}
if (BO0 && BO1 && BO0->getOpcode() == BO1->getOpcode() &&
BO0->hasOneUse() && BO1->hasOneUse() &&
BO0->getOperand(1) == BO1->getOperand(1)) {
switch (BO0->getOpcode()) {
default: break;
case Instruction::Add:
case Instruction::Sub:
case Instruction::Xor:
if (I.isEquality()) // a+x icmp eq/ne b+x --> a icmp b
return new ICmpInst(I.getPredicate(), BO0->getOperand(0),
BO1->getOperand(0));
// icmp u/s (a ^ signbit), (b ^ signbit) --> icmp s/u a, b
if (ConstantInt *CI = dyn_cast<ConstantInt>(BO0->getOperand(1))) {
if (CI->getValue().isSignBit()) {
ICmpInst::Predicate Pred = I.isSigned()
? I.getUnsignedPredicate()
: I.getSignedPredicate();
return new ICmpInst(Pred, BO0->getOperand(0),
BO1->getOperand(0));
}
if (CI->isMaxValue(true)) {
ICmpInst::Predicate Pred = I.isSigned()
? I.getUnsignedPredicate()
: I.getSignedPredicate();
Pred = I.getSwappedPredicate(Pred);
return new ICmpInst(Pred, BO0->getOperand(0),
BO1->getOperand(0));
}
}
break;
case Instruction::Mul:
if (!I.isEquality())
break;
if (ConstantInt *CI = dyn_cast<ConstantInt>(BO0->getOperand(1))) {
// a * Cst icmp eq/ne b * Cst --> a & Mask icmp b & Mask
// Mask = -1 >> count-trailing-zeros(Cst).
if (!CI->isZero() && !CI->isOne()) {
const APInt &AP = CI->getValue();
ConstantInt *Mask = ConstantInt::get(I.getContext(),
APInt::getLowBitsSet(AP.getBitWidth(),
AP.getBitWidth() -
AP.countTrailingZeros()));
Value *And1 = Builder->CreateAnd(BO0->getOperand(0), Mask);
Value *And2 = Builder->CreateAnd(BO1->getOperand(0), Mask);
return new ICmpInst(I.getPredicate(), And1, And2);
}
}
break;
case Instruction::UDiv:
case Instruction::LShr:
if (I.isSigned())
break;
LLVM_FALLTHROUGH; // HLSL Change
case Instruction::SDiv:
case Instruction::AShr:
if (!BO0->isExact() || !BO1->isExact())
break;
return new ICmpInst(I.getPredicate(), BO0->getOperand(0),
BO1->getOperand(0));
case Instruction::Shl: {
bool NUW = BO0->hasNoUnsignedWrap() && BO1->hasNoUnsignedWrap();
bool NSW = BO0->hasNoSignedWrap() && BO1->hasNoSignedWrap();
if (!NUW && !NSW)
break;
if (!NSW && I.isSigned())
break;
return new ICmpInst(I.getPredicate(), BO0->getOperand(0),
BO1->getOperand(0));
}
}
}
}
{ Value *A, *B;
// Transform (A & ~B) == 0 --> (A & B) != 0
// and (A & ~B) != 0 --> (A & B) == 0
// if A is a power of 2.
if (match(Op0, m_And(m_Value(A), m_Not(m_Value(B)))) &&
match(Op1, m_Zero()) &&
isKnownToBeAPowerOfTwo(A, DL, false, 0, AC, &I, DT) && I.isEquality())
return new ICmpInst(I.getInversePredicate(),
Builder->CreateAnd(A, B),
Op1);
// ~x < ~y --> y < x
// ~x < cst --> ~cst < x
if (match(Op0, m_Not(m_Value(A)))) {
if (match(Op1, m_Not(m_Value(B))))
return new ICmpInst(I.getPredicate(), B, A);
if (ConstantInt *RHSC = dyn_cast<ConstantInt>(Op1))
return new ICmpInst(I.getPredicate(), ConstantExpr::getNot(RHSC), A);
}
Instruction *AddI = nullptr;
if (match(&I, m_UAddWithOverflow(m_Value(A), m_Value(B),
m_Instruction(AddI))) &&
isa<IntegerType>(A->getType())) {
Value *Result;
Constant *Overflow;
if (OptimizeOverflowCheck(OCF_UNSIGNED_ADD, A, B, *AddI, Result,
Overflow)) {
ReplaceInstUsesWith(*AddI, Result);
return ReplaceInstUsesWith(I, Overflow);
}
}
// (zext a) * (zext b) --> llvm.umul.with.overflow.
if (match(Op0, m_Mul(m_ZExt(m_Value(A)), m_ZExt(m_Value(B))))) {
if (Instruction *R = ProcessUMulZExtIdiom(I, Op0, Op1, *this))
return R;
}
if (match(Op1, m_Mul(m_ZExt(m_Value(A)), m_ZExt(m_Value(B))))) {
if (Instruction *R = ProcessUMulZExtIdiom(I, Op1, Op0, *this))
return R;
}
}
if (I.isEquality()) {
Value *A, *B, *C, *D;
if (match(Op0, m_Xor(m_Value(A), m_Value(B)))) {
if (A == Op1 || B == Op1) { // (A^B) == A -> B == 0
Value *OtherVal = A == Op1 ? B : A;
return new ICmpInst(I.getPredicate(), OtherVal,
Constant::getNullValue(A->getType()));
}
if (match(Op1, m_Xor(m_Value(C), m_Value(D)))) {
// A^c1 == C^c2 --> A == C^(c1^c2)
ConstantInt *C1, *C2;
if (match(B, m_ConstantInt(C1)) &&
match(D, m_ConstantInt(C2)) && Op1->hasOneUse()) {
Constant *NC = Builder->getInt(C1->getValue() ^ C2->getValue());
Value *Xor = Builder->CreateXor(C, NC);
return new ICmpInst(I.getPredicate(), A, Xor);
}
// A^B == A^D -> B == D
if (A == C) return new ICmpInst(I.getPredicate(), B, D);
if (A == D) return new ICmpInst(I.getPredicate(), B, C);
if (B == C) return new ICmpInst(I.getPredicate(), A, D);
if (B == D) return new ICmpInst(I.getPredicate(), A, C);
}
}
if (match(Op1, m_Xor(m_Value(A), m_Value(B))) &&
(A == Op0 || B == Op0)) {
// A == (A^B) -> B == 0
Value *OtherVal = A == Op0 ? B : A;
return new ICmpInst(I.getPredicate(), OtherVal,
Constant::getNullValue(A->getType()));
}
// (X&Z) == (Y&Z) -> (X^Y) & Z == 0
if (match(Op0, m_OneUse(m_And(m_Value(A), m_Value(B)))) &&
match(Op1, m_OneUse(m_And(m_Value(C), m_Value(D))))) {
Value *X = nullptr, *Y = nullptr, *Z = nullptr;
if (A == C) {
X = B; Y = D; Z = A;
} else if (A == D) {
X = B; Y = C; Z = A;
} else if (B == C) {
X = A; Y = D; Z = B;
} else if (B == D) {
X = A; Y = C; Z = B;
}
if (X) { // Build (X^Y) & Z
Op1 = Builder->CreateXor(X, Y);
Op1 = Builder->CreateAnd(Op1, Z);
I.setOperand(0, Op1);
I.setOperand(1, Constant::getNullValue(Op1->getType()));
return &I;
}
}
// Transform (zext A) == (B & (1<<X)-1) --> A == (trunc B)
// and (B & (1<<X)-1) == (zext A) --> A == (trunc B)
ConstantInt *Cst1;
if ((Op0->hasOneUse() &&
match(Op0, m_ZExt(m_Value(A))) &&
match(Op1, m_And(m_Value(B), m_ConstantInt(Cst1)))) ||
(Op1->hasOneUse() &&
match(Op0, m_And(m_Value(B), m_ConstantInt(Cst1))) &&
match(Op1, m_ZExt(m_Value(A))))) {
APInt Pow2 = Cst1->getValue() + 1;
if (Pow2.isPowerOf2() && isa<IntegerType>(A->getType()) &&
Pow2.logBase2() == cast<IntegerType>(A->getType())->getBitWidth())
return new ICmpInst(I.getPredicate(), A,
Builder->CreateTrunc(B, A->getType()));
}
// (A >> C) == (B >> C) --> (A^B) u< (1 << C)
// For lshr and ashr pairs.
if ((match(Op0, m_OneUse(m_LShr(m_Value(A), m_ConstantInt(Cst1)))) &&
match(Op1, m_OneUse(m_LShr(m_Value(B), m_Specific(Cst1))))) ||
(match(Op0, m_OneUse(m_AShr(m_Value(A), m_ConstantInt(Cst1)))) &&
match(Op1, m_OneUse(m_AShr(m_Value(B), m_Specific(Cst1)))))) {
unsigned TypeBits = Cst1->getBitWidth();
unsigned ShAmt = (unsigned)Cst1->getLimitedValue(TypeBits);
if (ShAmt < TypeBits && ShAmt != 0) {
ICmpInst::Predicate Pred = I.getPredicate() == ICmpInst::ICMP_NE
? ICmpInst::ICMP_UGE
: ICmpInst::ICMP_ULT;
Value *Xor = Builder->CreateXor(A, B, I.getName() + ".unshifted");
APInt CmpVal = APInt::getOneBitSet(TypeBits, ShAmt);
return new ICmpInst(Pred, Xor, Builder->getInt(CmpVal));
}
}
// (A << C) == (B << C) --> ((A^B) & (~0U >> C)) == 0
if (match(Op0, m_OneUse(m_Shl(m_Value(A), m_ConstantInt(Cst1)))) &&
match(Op1, m_OneUse(m_Shl(m_Value(B), m_Specific(Cst1))))) {
unsigned TypeBits = Cst1->getBitWidth();
unsigned ShAmt = (unsigned)Cst1->getLimitedValue(TypeBits);
if (ShAmt < TypeBits && ShAmt != 0) {
Value *Xor = Builder->CreateXor(A, B, I.getName() + ".unshifted");
APInt AndVal = APInt::getLowBitsSet(TypeBits, TypeBits - ShAmt);
Value *And = Builder->CreateAnd(Xor, Builder->getInt(AndVal),
I.getName() + ".mask");
return new ICmpInst(I.getPredicate(), And,
Constant::getNullValue(Cst1->getType()));
}
}
// Transform "icmp eq (trunc (lshr(X, cst1)), cst" to
// "icmp (and X, mask), cst"
uint64_t ShAmt = 0;
if (Op0->hasOneUse() &&
match(Op0, m_Trunc(m_OneUse(m_LShr(m_Value(A),
m_ConstantInt(ShAmt))))) &&
match(Op1, m_ConstantInt(Cst1)) &&
// Only do this when A has multiple uses. This is most important to do
// when it exposes other optimizations.
!A->hasOneUse()) {
unsigned ASize =cast<IntegerType>(A->getType())->getPrimitiveSizeInBits();
if (ShAmt < ASize) {
APInt MaskV =
APInt::getLowBitsSet(ASize, Op0->getType()->getPrimitiveSizeInBits());
MaskV <<= ShAmt;
APInt CmpV = Cst1->getValue().zext(ASize);
CmpV <<= ShAmt;
Value *Mask = Builder->CreateAnd(A, Builder->getInt(MaskV));
return new ICmpInst(I.getPredicate(), Mask, Builder->getInt(CmpV));
}
}
}
// The 'cmpxchg' instruction returns an aggregate containing the old value and
// an i1 which indicates whether or not we successfully did the swap.
//
// Replace comparisons between the old value and the expected value with the
// indicator that 'cmpxchg' returns.
//
// N.B. This transform is only valid when the 'cmpxchg' is not permitted to
// spuriously fail. In those cases, the old value may equal the expected
// value but it is possible for the swap to not occur.
if (I.getPredicate() == ICmpInst::ICMP_EQ)
if (auto *EVI = dyn_cast<ExtractValueInst>(Op0))
if (auto *ACXI = dyn_cast<AtomicCmpXchgInst>(EVI->getAggregateOperand()))
if (EVI->getIndices()[0] == 0 && ACXI->getCompareOperand() == Op1 &&
!ACXI->isWeak())
return ExtractValueInst::Create(ACXI, 1);
{
Value *X; ConstantInt *Cst;
// icmp X+Cst, X
if (match(Op0, m_Add(m_Value(X), m_ConstantInt(Cst))) && Op1 == X)
return FoldICmpAddOpCst(I, X, Cst, I.getPredicate());
// icmp X, X+Cst
if (match(Op1, m_Add(m_Value(X), m_ConstantInt(Cst))) && Op0 == X)
return FoldICmpAddOpCst(I, X, Cst, I.getSwappedPredicate());
}
return Changed ? &I : nullptr;
}
/// FoldFCmp_IntToFP_Cst - Fold fcmp ([us]itofp x, cst) if possible.
Instruction *InstCombiner::FoldFCmp_IntToFP_Cst(FCmpInst &I,
Instruction *LHSI,
Constant *RHSC) {
if (!isa<ConstantFP>(RHSC)) return nullptr;
const APFloat &RHS = cast<ConstantFP>(RHSC)->getValueAPF();
// Get the width of the mantissa. We don't want to hack on conversions that
// might lose information from the integer, e.g. "i64 -> float"
int MantissaWidth = LHSI->getType()->getFPMantissaWidth();
if (MantissaWidth == -1) return nullptr; // Unknown.
IntegerType *IntTy = cast<IntegerType>(LHSI->getOperand(0)->getType());
// Check to see that the input is converted from an integer type that is small
// enough that preserves all bits. TODO: check here for "known" sign bits.
// This would allow us to handle (fptosi (x >>s 62) to float) if x is i64 f.e.
unsigned InputSize = IntTy->getScalarSizeInBits();
// If this is a uitofp instruction, we need an extra bit to hold the sign.
bool LHSUnsigned = isa<UIToFPInst>(LHSI);
if (LHSUnsigned)
++InputSize;
if (I.isEquality()) {
FCmpInst::Predicate P = I.getPredicate();
bool IsExact = false;
APSInt RHSCvt(IntTy->getBitWidth(), LHSUnsigned);
RHS.convertToInteger(RHSCvt, APFloat::rmNearestTiesToEven, &IsExact);
// If the floating point constant isn't an integer value, we know if we will
// ever compare equal / not equal to it.
if (!IsExact) {
// TODO: Can never be -0.0 and other non-representable values
APFloat RHSRoundInt(RHS);
RHSRoundInt.roundToIntegral(APFloat::rmNearestTiesToEven);
if (RHS.compare(RHSRoundInt) != APFloat::cmpEqual) {
if (P == FCmpInst::FCMP_OEQ || P == FCmpInst::FCMP_UEQ)
return ReplaceInstUsesWith(I, Builder->getFalse());
assert(P == FCmpInst::FCMP_ONE || P == FCmpInst::FCMP_UNE);
return ReplaceInstUsesWith(I, Builder->getTrue());
}
}
// TODO: If the constant is exactly representable, is it always OK to do
// equality compares as integer?
}
// Comparisons with zero are a special case where we know we won't lose
// information.
bool IsCmpZero = RHS.isPosZero();
// If the conversion would lose info, don't hack on this.
if ((int)InputSize > MantissaWidth && !IsCmpZero)
return nullptr;
// Otherwise, we can potentially simplify the comparison. We know that it
// will always come through as an integer value and we know the constant is
// not a NAN (it would have been previously simplified).
assert(!RHS.isNaN() && "NaN comparison not already folded!");
ICmpInst::Predicate Pred;
switch (I.getPredicate()) {
default: llvm_unreachable("Unexpected predicate!");
case FCmpInst::FCMP_UEQ:
case FCmpInst::FCMP_OEQ:
Pred = ICmpInst::ICMP_EQ;
break;
case FCmpInst::FCMP_UGT:
case FCmpInst::FCMP_OGT:
Pred = LHSUnsigned ? ICmpInst::ICMP_UGT : ICmpInst::ICMP_SGT;
break;
case FCmpInst::FCMP_UGE:
case FCmpInst::FCMP_OGE:
Pred = LHSUnsigned ? ICmpInst::ICMP_UGE : ICmpInst::ICMP_SGE;
break;
case FCmpInst::FCMP_ULT:
case FCmpInst::FCMP_OLT:
Pred = LHSUnsigned ? ICmpInst::ICMP_ULT : ICmpInst::ICMP_SLT;
break;
case FCmpInst::FCMP_ULE:
case FCmpInst::FCMP_OLE:
Pred = LHSUnsigned ? ICmpInst::ICMP_ULE : ICmpInst::ICMP_SLE;
break;
case FCmpInst::FCMP_UNE:
case FCmpInst::FCMP_ONE:
Pred = ICmpInst::ICMP_NE;
break;
case FCmpInst::FCMP_ORD:
return ReplaceInstUsesWith(I, Builder->getTrue());
case FCmpInst::FCMP_UNO:
return ReplaceInstUsesWith(I, Builder->getFalse());
}
// Now we know that the APFloat is a normal number, zero or inf.
// See if the FP constant is too large for the integer. For example,
// comparing an i8 to 300.0.
unsigned IntWidth = IntTy->getScalarSizeInBits();
if (!LHSUnsigned) {
// If the RHS value is > SignedMax, fold the comparison. This handles +INF
// and large values.
APFloat SMax(RHS.getSemantics());
SMax.convertFromAPInt(APInt::getSignedMaxValue(IntWidth), true,
APFloat::rmNearestTiesToEven);
if (SMax.compare(RHS) == APFloat::cmpLessThan) { // smax < 13123.0
if (Pred == ICmpInst::ICMP_NE || Pred == ICmpInst::ICMP_SLT ||
Pred == ICmpInst::ICMP_SLE)
return ReplaceInstUsesWith(I, Builder->getTrue());
return ReplaceInstUsesWith(I, Builder->getFalse());
}
} else {
// If the RHS value is > UnsignedMax, fold the comparison. This handles
// +INF and large values.
APFloat UMax(RHS.getSemantics());
UMax.convertFromAPInt(APInt::getMaxValue(IntWidth), false,
APFloat::rmNearestTiesToEven);
if (UMax.compare(RHS) == APFloat::cmpLessThan) { // umax < 13123.0
if (Pred == ICmpInst::ICMP_NE || Pred == ICmpInst::ICMP_ULT ||
Pred == ICmpInst::ICMP_ULE)
return ReplaceInstUsesWith(I, Builder->getTrue());
return ReplaceInstUsesWith(I, Builder->getFalse());
}
}
if (!LHSUnsigned) {
// See if the RHS value is < SignedMin.
APFloat SMin(RHS.getSemantics());
SMin.convertFromAPInt(APInt::getSignedMinValue(IntWidth), true,
APFloat::rmNearestTiesToEven);
if (SMin.compare(RHS) == APFloat::cmpGreaterThan) { // smin > 12312.0
if (Pred == ICmpInst::ICMP_NE || Pred == ICmpInst::ICMP_SGT ||
Pred == ICmpInst::ICMP_SGE)
return ReplaceInstUsesWith(I, Builder->getTrue());
return ReplaceInstUsesWith(I, Builder->getFalse());
}
} else {
// See if the RHS value is < UnsignedMin.
APFloat SMin(RHS.getSemantics());
SMin.convertFromAPInt(APInt::getMinValue(IntWidth), true,
APFloat::rmNearestTiesToEven);
if (SMin.compare(RHS) == APFloat::cmpGreaterThan) { // umin > 12312.0
if (Pred == ICmpInst::ICMP_NE || Pred == ICmpInst::ICMP_UGT ||
Pred == ICmpInst::ICMP_UGE)
return ReplaceInstUsesWith(I, Builder->getTrue());
return ReplaceInstUsesWith(I, Builder->getFalse());
}
}
// Okay, now we know that the FP constant fits in the range [SMIN, SMAX] or
// [0, UMAX], but it may still be fractional. See if it is fractional by
// casting the FP value to the integer value and back, checking for equality.
// Don't do this for zero, because -0.0 is not fractional.
Constant *RHSInt = LHSUnsigned
? ConstantExpr::getFPToUI(RHSC, IntTy)
: ConstantExpr::getFPToSI(RHSC, IntTy);
if (!RHS.isZero()) {
bool Equal = LHSUnsigned
? ConstantExpr::getUIToFP(RHSInt, RHSC->getType()) == RHSC
: ConstantExpr::getSIToFP(RHSInt, RHSC->getType()) == RHSC;
if (!Equal) {
// If we had a comparison against a fractional value, we have to adjust
// the compare predicate and sometimes the value. RHSC is rounded towards
// zero at this point.
switch (Pred) {
default: llvm_unreachable("Unexpected integer comparison!");
case ICmpInst::ICMP_NE: // (float)int != 4.4 --> true
return ReplaceInstUsesWith(I, Builder->getTrue());
case ICmpInst::ICMP_EQ: // (float)int == 4.4 --> false
return ReplaceInstUsesWith(I, Builder->getFalse());
case ICmpInst::ICMP_ULE:
// (float)int <= 4.4 --> int <= 4
// (float)int <= -4.4 --> false
if (RHS.isNegative())
return ReplaceInstUsesWith(I, Builder->getFalse());
break;
case ICmpInst::ICMP_SLE:
// (float)int <= 4.4 --> int <= 4
// (float)int <= -4.4 --> int < -4
if (RHS.isNegative())
Pred = ICmpInst::ICMP_SLT;
break;
case ICmpInst::ICMP_ULT:
// (float)int < -4.4 --> false
// (float)int < 4.4 --> int <= 4
if (RHS.isNegative())
return ReplaceInstUsesWith(I, Builder->getFalse());
Pred = ICmpInst::ICMP_ULE;
break;
case ICmpInst::ICMP_SLT:
// (float)int < -4.4 --> int < -4
// (float)int < 4.4 --> int <= 4
if (!RHS.isNegative())
Pred = ICmpInst::ICMP_SLE;
break;
case ICmpInst::ICMP_UGT:
// (float)int > 4.4 --> int > 4
// (float)int > -4.4 --> true
if (RHS.isNegative())
return ReplaceInstUsesWith(I, Builder->getTrue());
break;
case ICmpInst::ICMP_SGT:
// (float)int > 4.4 --> int > 4
// (float)int > -4.4 --> int >= -4
if (RHS.isNegative())
Pred = ICmpInst::ICMP_SGE;
break;
case ICmpInst::ICMP_UGE:
// (float)int >= -4.4 --> true
// (float)int >= 4.4 --> int > 4
if (RHS.isNegative())
return ReplaceInstUsesWith(I, Builder->getTrue());
Pred = ICmpInst::ICMP_UGT;
break;
case ICmpInst::ICMP_SGE:
// (float)int >= -4.4 --> int >= -4
// (float)int >= 4.4 --> int > 4
if (!RHS.isNegative())
Pred = ICmpInst::ICMP_SGT;
break;
}
}
}
// Lower this FP comparison into an appropriate integer version of the
// comparison.
return new ICmpInst(Pred, LHSI->getOperand(0), RHSInt);
}
Instruction *InstCombiner::visitFCmpInst(FCmpInst &I) {
bool Changed = false;
/// Orders the operands of the compare so that they are listed from most
/// complex to least complex. This puts constants before unary operators,
/// before binary operators.
if (getComplexity(I.getOperand(0)) < getComplexity(I.getOperand(1))) {
I.swapOperands();
Changed = true;
}
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyFCmpInst(I.getPredicate(), Op0, Op1,
I.getFastMathFlags(), DL, TLI, DT, AC, &I))
return ReplaceInstUsesWith(I, V);
// Simplify 'fcmp pred X, X'
if (Op0 == Op1) {
switch (I.getPredicate()) {
default: llvm_unreachable("Unknown predicate!");
case FCmpInst::FCMP_UNO: // True if unordered: isnan(X) | isnan(Y)
case FCmpInst::FCMP_ULT: // True if unordered or less than
case FCmpInst::FCMP_UGT: // True if unordered or greater than
case FCmpInst::FCMP_UNE: // True if unordered or not equal
// Canonicalize these to be 'fcmp uno %X, 0.0'.
I.setPredicate(FCmpInst::FCMP_UNO);
I.setOperand(1, Constant::getNullValue(Op0->getType()));
return &I;
case FCmpInst::FCMP_ORD: // True if ordered (no nans)
case FCmpInst::FCMP_OEQ: // True if ordered and equal
case FCmpInst::FCMP_OGE: // True if ordered and greater than or equal
case FCmpInst::FCMP_OLE: // True if ordered and less than or equal
// Canonicalize these to be 'fcmp ord %X, 0.0'.
I.setPredicate(FCmpInst::FCMP_ORD);
I.setOperand(1, Constant::getNullValue(Op0->getType()));
return &I;
}
}
// Test if the FCmpInst instruction is used exclusively by a select as
// part of a minimum or maximum operation. If so, refrain from doing
// any other folding. This helps out other analyses which understand
// non-obfuscated minimum and maximum idioms, such as ScalarEvolution
// and CodeGen. And in this case, at least one of the comparison
// operands has at least one user besides the compare (the select),
// which would often largely negate the benefit of folding anyway.
if (I.hasOneUse())
if (SelectInst *SI = dyn_cast<SelectInst>(*I.user_begin()))
if ((SI->getOperand(1) == Op0 && SI->getOperand(2) == Op1) ||
(SI->getOperand(2) == Op0 && SI->getOperand(1) == Op1))
return nullptr;
// Handle fcmp with constant RHS
if (Constant *RHSC = dyn_cast<Constant>(Op1)) {
if (Instruction *LHSI = dyn_cast<Instruction>(Op0))
switch (LHSI->getOpcode()) {
case Instruction::FPExt: {
// fcmp (fpext x), C -> fcmp x, (fptrunc C) if fptrunc is lossless
FPExtInst *LHSExt = cast<FPExtInst>(LHSI);
ConstantFP *RHSF = dyn_cast<ConstantFP>(RHSC);
if (!RHSF)
break;
const fltSemantics *Sem;
// FIXME: This shouldn't be here.
if (LHSExt->getSrcTy()->isHalfTy())
Sem = &APFloat::IEEEhalf;
else if (LHSExt->getSrcTy()->isFloatTy())
Sem = &APFloat::IEEEsingle;
else if (LHSExt->getSrcTy()->isDoubleTy())
Sem = &APFloat::IEEEdouble;
else if (LHSExt->getSrcTy()->isFP128Ty())
Sem = &APFloat::IEEEquad;
else if (LHSExt->getSrcTy()->isX86_FP80Ty())
Sem = &APFloat::x87DoubleExtended;
else if (LHSExt->getSrcTy()->isPPC_FP128Ty())
Sem = &APFloat::PPCDoubleDouble;
else
break;
bool Lossy;
APFloat F = RHSF->getValueAPF();
F.convert(*Sem, APFloat::rmNearestTiesToEven, &Lossy);
// Avoid lossy conversions and denormals. Zero is a special case
// that's OK to convert.
APFloat Fabs = F;
Fabs.clearSign();
if (!Lossy &&
((Fabs.compare(APFloat::getSmallestNormalized(*Sem)) !=
APFloat::cmpLessThan) || Fabs.isZero()))
return new FCmpInst(I.getPredicate(), LHSExt->getOperand(0),
ConstantFP::get(RHSC->getContext(), F));
break;
}
case Instruction::PHI:
// Only fold fcmp into the PHI if the phi and fcmp are in the same
// block. If in the same block, we're encouraging jump threading. If
// not, we are just pessimizing the code by making an i1 phi.
if (LHSI->getParent() == I.getParent())
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
break;
case Instruction::SIToFP:
case Instruction::UIToFP:
if (Instruction *NV = FoldFCmp_IntToFP_Cst(I, LHSI, RHSC))
return NV;
break;
case Instruction::FSub: {
// fcmp pred (fneg x), C -> fcmp swap(pred) x, -C
Value *Op;
if (match(LHSI, m_FNeg(m_Value(Op))))
return new FCmpInst(I.getSwappedPredicate(), Op,
ConstantExpr::getFNeg(RHSC));
break;
}
case Instruction::Load:
if (GetElementPtrInst *GEP =
dyn_cast<GetElementPtrInst>(LHSI->getOperand(0))) {
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(GEP->getOperand(0)))
if (GV->isConstant() && GV->hasDefinitiveInitializer() &&
!cast<LoadInst>(LHSI)->isVolatile())
if (Instruction *Res = FoldCmpLoadFromIndexedGlobal(GEP, GV, I))
return Res;
}
break;
case Instruction::Call: {
if (!RHSC->isNullValue())
break;
CallInst *CI = cast<CallInst>(LHSI);
const Function *F = CI->getCalledFunction();
if (!F)
break;
// Various optimization for fabs compared with zero.
LibFunc::Func Func;
if (F->getIntrinsicID() == Intrinsic::fabs ||
(TLI->getLibFunc(F->getName(), Func) && TLI->has(Func) &&
(Func == LibFunc::fabs || Func == LibFunc::fabsf ||
Func == LibFunc::fabsl))) {
switch (I.getPredicate()) {
default:
break;
// fabs(x) < 0 --> false
case FCmpInst::FCMP_OLT:
return ReplaceInstUsesWith(I, Builder->getFalse());
// fabs(x) > 0 --> x != 0
case FCmpInst::FCMP_OGT:
return new FCmpInst(FCmpInst::FCMP_ONE, CI->getArgOperand(0), RHSC);
// fabs(x) <= 0 --> x == 0
case FCmpInst::FCMP_OLE:
return new FCmpInst(FCmpInst::FCMP_OEQ, CI->getArgOperand(0), RHSC);
// fabs(x) >= 0 --> !isnan(x)
case FCmpInst::FCMP_OGE:
return new FCmpInst(FCmpInst::FCMP_ORD, CI->getArgOperand(0), RHSC);
// fabs(x) == 0 --> x == 0
// fabs(x) != 0 --> x != 0
case FCmpInst::FCMP_OEQ:
case FCmpInst::FCMP_UEQ:
case FCmpInst::FCMP_ONE:
case FCmpInst::FCMP_UNE:
return new FCmpInst(I.getPredicate(), CI->getArgOperand(0), RHSC);
}
}
}
}
}
// fcmp pred (fneg x), (fneg y) -> fcmp swap(pred) x, y
Value *X, *Y;
if (match(Op0, m_FNeg(m_Value(X))) && match(Op1, m_FNeg(m_Value(Y))))
return new FCmpInst(I.getSwappedPredicate(), X, Y);
// fcmp (fpext x), (fpext y) -> fcmp x, y
if (FPExtInst *LHSExt = dyn_cast<FPExtInst>(Op0))
if (FPExtInst *RHSExt = dyn_cast<FPExtInst>(Op1))
if (LHSExt->getSrcTy() == RHSExt->getSrcTy())
return new FCmpInst(I.getPredicate(), LHSExt->getOperand(0),
RHSExt->getOperand(0));
return Changed ? &I : nullptr;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/InstCombineAddSub.cpp | //===- InstCombineAddSub.cpp ----------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the visit functions for add, fadd, sub, and fsub.
//
//===----------------------------------------------------------------------===//
#include "InstCombineInternal.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/PatternMatch.h"
using namespace llvm;
using namespace PatternMatch;
#define DEBUG_TYPE "instcombine"
namespace {
/// Class representing coefficient of floating-point addend.
/// This class needs to be highly efficient, which is especially true for
/// the constructor. As of I write this comment, the cost of the default
/// constructor is merely 4-byte-store-zero (Assuming compiler is able to
/// perform write-merging).
///
class FAddendCoef {
public:
// The constructor has to initialize a APFloat, which is unnecessary for
// most addends which have coefficient either 1 or -1. So, the constructor
// is expensive. In order to avoid the cost of the constructor, we should
// reuse some instances whenever possible. The pre-created instances
// FAddCombine::Add[0-5] embodies this idea.
//
FAddendCoef() : IsFp(false), BufHasFpVal(false), IntVal(0) {}
~FAddendCoef();
void set(short C) {
assert(!insaneIntVal(C) && "Insane coefficient");
IsFp = false; IntVal = C;
}
void set(const APFloat& C);
void negate();
bool isZero() const { return isInt() ? !IntVal : getFpVal().isZero(); }
Value *getValue(Type *) const;
// If possible, don't define operator+/operator- etc because these
// operators inevitably call FAddendCoef's constructor which is not cheap.
void operator=(const FAddendCoef &A);
void operator+=(const FAddendCoef &A);
void operator-=(const FAddendCoef &A);
void operator*=(const FAddendCoef &S);
bool isOne() const { return isInt() && IntVal == 1; }
bool isTwo() const { return isInt() && IntVal == 2; }
bool isMinusOne() const { return isInt() && IntVal == -1; }
bool isMinusTwo() const { return isInt() && IntVal == -2; }
private:
bool insaneIntVal(int V) { return V > 4 || V < -4; }
APFloat *getFpValPtr(void)
{ return reinterpret_cast<APFloat*>(&FpValBuf.buffer[0]); }
const APFloat *getFpValPtr(void) const
{ return reinterpret_cast<const APFloat*>(&FpValBuf.buffer[0]); }
const APFloat &getFpVal(void) const {
assert(IsFp && BufHasFpVal && "Incorret state");
return *getFpValPtr();
}
APFloat &getFpVal(void) {
assert(IsFp && BufHasFpVal && "Incorret state");
return *getFpValPtr();
}
bool isInt() const { return !IsFp; }
// If the coefficient is represented by an integer, promote it to a
// floating point.
void convertToFpType(const fltSemantics &Sem);
// Construct an APFloat from a signed integer.
// TODO: We should get rid of this function when APFloat can be constructed
// from an *SIGNED* integer.
APFloat createAPFloatFromInt(const fltSemantics &Sem, int Val);
private:
bool IsFp;
// True iff FpValBuf contains an instance of APFloat.
bool BufHasFpVal;
// The integer coefficient of an individual addend is either 1 or -1,
// and we try to simplify at most 4 addends from neighboring at most
// two instructions. So the range of <IntVal> falls in [-4, 4]. APInt
// is overkill of this end.
short IntVal;
AlignedCharArrayUnion<APFloat> FpValBuf;
};
/// FAddend is used to represent floating-point addend. An addend is
/// represented as <C, V>, where the V is a symbolic value, and C is a
/// constant coefficient. A constant addend is represented as <C, 0>.
///
class FAddend {
public:
FAddend() { Val = nullptr; }
Value *getSymVal (void) const { return Val; }
const FAddendCoef &getCoef(void) const { return Coeff; }
bool isConstant() const { return Val == nullptr; }
bool isZero() const { return Coeff.isZero(); }
void set(short Coefficient, Value *V) { Coeff.set(Coefficient), Val = V; }
void set(const APFloat& Coefficient, Value *V)
{ Coeff.set(Coefficient); Val = V; }
void set(const ConstantFP* Coefficient, Value *V)
{ Coeff.set(Coefficient->getValueAPF()); Val = V; }
void negate() { Coeff.negate(); }
/// Drill down the U-D chain one step to find the definition of V, and
/// try to break the definition into one or two addends.
static unsigned drillValueDownOneStep(Value* V, FAddend &A0, FAddend &A1);
/// Similar to FAddend::drillDownOneStep() except that the value being
/// splitted is the addend itself.
unsigned drillAddendDownOneStep(FAddend &Addend0, FAddend &Addend1) const;
void operator+=(const FAddend &T) {
assert((Val == T.Val) && "Symbolic-values disagree");
Coeff += T.Coeff;
}
private:
void Scale(const FAddendCoef& ScaleAmt) { Coeff *= ScaleAmt; }
// This addend has the value of "Coeff * Val".
Value *Val;
FAddendCoef Coeff;
};
/// FAddCombine is the class for optimizing an unsafe fadd/fsub along
/// with its neighboring at most two instructions.
///
class FAddCombine {
public:
FAddCombine(InstCombiner::BuilderTy *B) : Builder(B), Instr(nullptr) {}
Value *simplify(Instruction *FAdd);
private:
typedef SmallVector<const FAddend*, 4> AddendVect;
Value *simplifyFAdd(AddendVect& V, unsigned InstrQuota);
Value *performFactorization(Instruction *I);
/// Convert given addend to a Value
Value *createAddendVal(const FAddend &A, bool& NeedNeg);
/// Return the number of instructions needed to emit the N-ary addition.
unsigned calcInstrNumber(const AddendVect& Vect);
Value *createFSub(Value *Opnd0, Value *Opnd1);
Value *createFAdd(Value *Opnd0, Value *Opnd1);
Value *createFMul(Value *Opnd0, Value *Opnd1);
Value *createFDiv(Value *Opnd0, Value *Opnd1);
Value *createFNeg(Value *V);
Value *createNaryFAdd(const AddendVect& Opnds, unsigned InstrQuota);
void createInstPostProc(Instruction *NewInst, bool NoNumber = false);
InstCombiner::BuilderTy *Builder;
Instruction *Instr;
private:
// Debugging stuff are clustered here.
#ifndef NDEBUG
unsigned CreateInstrNum;
void initCreateInstNum() { CreateInstrNum = 0; }
void incCreateInstNum() { CreateInstrNum++; }
#else
void initCreateInstNum() {}
void incCreateInstNum() {}
#endif
};
}
//===----------------------------------------------------------------------===//
//
// Implementation of
// {FAddendCoef, FAddend, FAddition, FAddCombine}.
//
//===----------------------------------------------------------------------===//
FAddendCoef::~FAddendCoef() {
if (BufHasFpVal)
getFpValPtr()->~APFloat();
}
void FAddendCoef::set(const APFloat& C) {
APFloat *P = getFpValPtr();
if (isInt()) {
// As the buffer is meanless byte stream, we cannot call
// APFloat::operator=().
new(P) APFloat(C);
} else
*P = C;
IsFp = BufHasFpVal = true;
}
void FAddendCoef::convertToFpType(const fltSemantics &Sem) {
if (!isInt())
return;
APFloat *P = getFpValPtr();
if (IntVal > 0)
new(P) APFloat(Sem, IntVal);
else {
new(P) APFloat(Sem, 0 - IntVal);
P->changeSign();
}
IsFp = BufHasFpVal = true;
}
APFloat FAddendCoef::createAPFloatFromInt(const fltSemantics &Sem, int Val) {
if (Val >= 0)
return APFloat(Sem, Val);
APFloat T(Sem, 0 - Val);
T.changeSign();
return T;
}
void FAddendCoef::operator=(const FAddendCoef &That) {
if (That.isInt())
set(That.IntVal);
else
set(That.getFpVal());
}
void FAddendCoef::operator+=(const FAddendCoef &That) {
enum APFloat::roundingMode RndMode = APFloat::rmNearestTiesToEven;
if (isInt() == That.isInt()) {
if (isInt())
IntVal += That.IntVal;
else
getFpVal().add(That.getFpVal(), RndMode);
return;
}
if (isInt()) {
const APFloat &T = That.getFpVal();
convertToFpType(T.getSemantics());
getFpVal().add(T, RndMode);
return;
}
APFloat &T = getFpVal();
T.add(createAPFloatFromInt(T.getSemantics(), That.IntVal), RndMode);
}
void FAddendCoef::operator-=(const FAddendCoef &That) {
enum APFloat::roundingMode RndMode = APFloat::rmNearestTiesToEven;
if (isInt() == That.isInt()) {
if (isInt())
IntVal -= That.IntVal;
else
getFpVal().subtract(That.getFpVal(), RndMode);
return;
}
if (isInt()) {
const APFloat &T = That.getFpVal();
convertToFpType(T.getSemantics());
getFpVal().subtract(T, RndMode);
return;
}
APFloat &T = getFpVal();
T.subtract(createAPFloatFromInt(T.getSemantics(), IntVal), RndMode);
}
void FAddendCoef::operator*=(const FAddendCoef &That) {
if (That.isOne())
return;
if (That.isMinusOne()) {
negate();
return;
}
if (isInt() && That.isInt()) {
int Res = IntVal * (int)That.IntVal;
assert(!insaneIntVal(Res) && "Insane int value");
IntVal = Res;
return;
}
const fltSemantics &Semantic =
isInt() ? That.getFpVal().getSemantics() : getFpVal().getSemantics();
if (isInt())
convertToFpType(Semantic);
APFloat &F0 = getFpVal();
if (That.isInt())
F0.multiply(createAPFloatFromInt(Semantic, That.IntVal),
APFloat::rmNearestTiesToEven);
else
F0.multiply(That.getFpVal(), APFloat::rmNearestTiesToEven);
return;
}
void FAddendCoef::negate() {
if (isInt())
IntVal = 0 - IntVal;
else
getFpVal().changeSign();
}
Value *FAddendCoef::getValue(Type *Ty) const {
return isInt() ?
ConstantFP::get(Ty, float(IntVal)) :
ConstantFP::get(Ty->getContext(), getFpVal());
}
// The definition of <Val> Addends
// =========================================
// A + B <1, A>, <1,B>
// A - B <1, A>, <1,B>
// 0 - B <-1, B>
// C * A, <C, A>
// A + C <1, A> <C, NULL>
// 0 +/- 0 <0, NULL> (corner case)
//
// Legend: A and B are not constant, C is constant
//
unsigned FAddend::drillValueDownOneStep
(Value *Val, FAddend &Addend0, FAddend &Addend1) {
Instruction *I = nullptr;
if (!Val || !(I = dyn_cast<Instruction>(Val)))
return 0;
unsigned Opcode = I->getOpcode();
if (Opcode == Instruction::FAdd || Opcode == Instruction::FSub) {
ConstantFP *C0, *C1;
Value *Opnd0 = I->getOperand(0);
Value *Opnd1 = I->getOperand(1);
if ((C0 = dyn_cast<ConstantFP>(Opnd0)) && C0->isZero())
Opnd0 = nullptr;
if ((C1 = dyn_cast<ConstantFP>(Opnd1)) && C1->isZero())
Opnd1 = nullptr;
if (Opnd0) {
if (!C0)
Addend0.set(1, Opnd0);
else
Addend0.set(C0, nullptr);
}
if (Opnd1) {
FAddend &Addend = Opnd0 ? Addend1 : Addend0;
if (!C1)
Addend.set(1, Opnd1);
else
Addend.set(C1, nullptr);
if (Opcode == Instruction::FSub)
Addend.negate();
}
if (Opnd0 || Opnd1)
return Opnd0 && Opnd1 ? 2 : 1;
// Both operands are zero. Weird!
Addend0.set(APFloat(C0->getValueAPF().getSemantics()), nullptr);
return 1;
}
if (I->getOpcode() == Instruction::FMul) {
Value *V0 = I->getOperand(0);
Value *V1 = I->getOperand(1);
if (ConstantFP *C = dyn_cast<ConstantFP>(V0)) {
Addend0.set(C, V1);
return 1;
}
if (ConstantFP *C = dyn_cast<ConstantFP>(V1)) {
Addend0.set(C, V0);
return 1;
}
}
return 0;
}
// Try to break *this* addend into two addends. e.g. Suppose this addend is
// <2.3, V>, and V = X + Y, by calling this function, we obtain two addends,
// i.e. <2.3, X> and <2.3, Y>.
//
unsigned FAddend::drillAddendDownOneStep
(FAddend &Addend0, FAddend &Addend1) const {
if (isConstant())
return 0;
unsigned BreakNum = FAddend::drillValueDownOneStep(Val, Addend0, Addend1);
if (!BreakNum || Coeff.isOne())
return BreakNum;
Addend0.Scale(Coeff);
if (BreakNum == 2)
Addend1.Scale(Coeff);
return BreakNum;
}
// Try to perform following optimization on the input instruction I. Return the
// simplified expression if was successful; otherwise, return 0.
//
// Instruction "I" is Simplified into
// -------------------------------------------------------
// (x * y) +/- (x * z) x * (y +/- z)
// (y / x) +/- (z / x) (y +/- z) / x
//
Value *FAddCombine::performFactorization(Instruction *I) {
assert((I->getOpcode() == Instruction::FAdd ||
I->getOpcode() == Instruction::FSub) && "Expect add/sub");
Instruction *I0 = dyn_cast<Instruction>(I->getOperand(0));
Instruction *I1 = dyn_cast<Instruction>(I->getOperand(1));
if (!I0 || !I1 || I0->getOpcode() != I1->getOpcode())
return nullptr;
bool isMpy = false;
if (I0->getOpcode() == Instruction::FMul)
isMpy = true;
else if (I0->getOpcode() != Instruction::FDiv)
return nullptr;
Value *Opnd0_0 = I0->getOperand(0);
Value *Opnd0_1 = I0->getOperand(1);
Value *Opnd1_0 = I1->getOperand(0);
Value *Opnd1_1 = I1->getOperand(1);
// Input Instr I Factor AddSub0 AddSub1
// ----------------------------------------------
// (x*y) +/- (x*z) x y z
// (y/x) +/- (z/x) x y z
//
Value *Factor = nullptr;
Value *AddSub0 = nullptr, *AddSub1 = nullptr;
if (isMpy) {
if (Opnd0_0 == Opnd1_0 || Opnd0_0 == Opnd1_1)
Factor = Opnd0_0;
else if (Opnd0_1 == Opnd1_0 || Opnd0_1 == Opnd1_1)
Factor = Opnd0_1;
if (Factor) {
AddSub0 = (Factor == Opnd0_0) ? Opnd0_1 : Opnd0_0;
AddSub1 = (Factor == Opnd1_0) ? Opnd1_1 : Opnd1_0;
}
} else if (Opnd0_1 == Opnd1_1) {
Factor = Opnd0_1;
AddSub0 = Opnd0_0;
AddSub1 = Opnd1_0;
}
if (!Factor)
return nullptr;
FastMathFlags Flags;
Flags.setUnsafeAlgebra();
if (I0) Flags &= I->getFastMathFlags();
if (I1) Flags &= I->getFastMathFlags();
// Create expression "NewAddSub = AddSub0 +/- AddsSub1"
Value *NewAddSub = (I->getOpcode() == Instruction::FAdd) ?
createFAdd(AddSub0, AddSub1) :
createFSub(AddSub0, AddSub1);
if (ConstantFP *CFP = dyn_cast<ConstantFP>(NewAddSub)) {
const APFloat &F = CFP->getValueAPF();
if (!F.isNormal())
return nullptr;
} else if (Instruction *II = dyn_cast<Instruction>(NewAddSub))
II->setFastMathFlags(Flags);
if (isMpy) {
Value *RI = createFMul(Factor, NewAddSub);
if (Instruction *II = dyn_cast<Instruction>(RI))
II->setFastMathFlags(Flags);
return RI;
}
Value *RI = createFDiv(NewAddSub, Factor);
if (Instruction *II = dyn_cast<Instruction>(RI))
II->setFastMathFlags(Flags);
return RI;
}
Value *FAddCombine::simplify(Instruction *I) {
assert(I->hasUnsafeAlgebra() && "Should be in unsafe mode");
// Currently we are not able to handle vector type.
if (I->getType()->isVectorTy())
return nullptr;
assert((I->getOpcode() == Instruction::FAdd ||
I->getOpcode() == Instruction::FSub) && "Expect add/sub");
// Save the instruction before calling other member-functions.
Instr = I;
FAddend Opnd0, Opnd1, Opnd0_0, Opnd0_1, Opnd1_0, Opnd1_1;
unsigned OpndNum = FAddend::drillValueDownOneStep(I, Opnd0, Opnd1);
// Step 1: Expand the 1st addend into Opnd0_0 and Opnd0_1.
unsigned Opnd0_ExpNum = 0;
unsigned Opnd1_ExpNum = 0;
if (!Opnd0.isConstant())
Opnd0_ExpNum = Opnd0.drillAddendDownOneStep(Opnd0_0, Opnd0_1);
// Step 2: Expand the 2nd addend into Opnd1_0 and Opnd1_1.
if (OpndNum == 2 && !Opnd1.isConstant())
Opnd1_ExpNum = Opnd1.drillAddendDownOneStep(Opnd1_0, Opnd1_1);
// Step 3: Try to optimize Opnd0_0 + Opnd0_1 + Opnd1_0 + Opnd1_1
if (Opnd0_ExpNum && Opnd1_ExpNum) {
AddendVect AllOpnds;
AllOpnds.push_back(&Opnd0_0);
AllOpnds.push_back(&Opnd1_0);
if (Opnd0_ExpNum == 2)
AllOpnds.push_back(&Opnd0_1);
if (Opnd1_ExpNum == 2)
AllOpnds.push_back(&Opnd1_1);
// Compute instruction quota. We should save at least one instruction.
unsigned InstQuota = 0;
Value *V0 = I->getOperand(0);
Value *V1 = I->getOperand(1);
InstQuota = ((!isa<Constant>(V0) && V0->hasOneUse()) &&
(!isa<Constant>(V1) && V1->hasOneUse())) ? 2 : 1;
if (Value *R = simplifyFAdd(AllOpnds, InstQuota))
return R;
}
if (OpndNum != 2) {
// The input instruction is : "I=0.0 +/- V". If the "V" were able to be
// splitted into two addends, say "V = X - Y", the instruction would have
// been optimized into "I = Y - X" in the previous steps.
//
const FAddendCoef &CE = Opnd0.getCoef();
return CE.isOne() ? Opnd0.getSymVal() : nullptr;
}
// step 4: Try to optimize Opnd0 + Opnd1_0 [+ Opnd1_1]
if (Opnd1_ExpNum) {
AddendVect AllOpnds;
AllOpnds.push_back(&Opnd0);
AllOpnds.push_back(&Opnd1_0);
if (Opnd1_ExpNum == 2)
AllOpnds.push_back(&Opnd1_1);
if (Value *R = simplifyFAdd(AllOpnds, 1))
return R;
}
// step 5: Try to optimize Opnd1 + Opnd0_0 [+ Opnd0_1]
if (Opnd0_ExpNum) {
AddendVect AllOpnds;
AllOpnds.push_back(&Opnd1);
AllOpnds.push_back(&Opnd0_0);
if (Opnd0_ExpNum == 2)
AllOpnds.push_back(&Opnd0_1);
if (Value *R = simplifyFAdd(AllOpnds, 1))
return R;
}
// step 6: Try factorization as the last resort,
return performFactorization(I);
}
Value *FAddCombine::simplifyFAdd(AddendVect& Addends, unsigned InstrQuota) {
unsigned AddendNum = Addends.size();
assert(AddendNum <= 4 && "Too many addends");
// For saving intermediate results;
unsigned NextTmpIdx = 0;
FAddend TmpResult[3];
// Points to the constant addend of the resulting simplified expression.
// If the resulting expr has constant-addend, this constant-addend is
// desirable to reside at the top of the resulting expression tree. Placing
// constant close to supper-expr(s) will potentially reveal some optimization
// opportunities in super-expr(s).
//
const FAddend *ConstAdd = nullptr;
// Simplified addends are placed <SimpVect>.
AddendVect SimpVect;
// The outer loop works on one symbolic-value at a time. Suppose the input
// addends are : <a1, x>, <b1, y>, <a2, x>, <c1, z>, <b2, y>, ...
// The symbolic-values will be processed in this order: x, y, z.
//
for (unsigned SymIdx = 0; SymIdx < AddendNum; SymIdx++) {
const FAddend *ThisAddend = Addends[SymIdx];
if (!ThisAddend) {
// This addend was processed before.
continue;
}
Value *Val = ThisAddend->getSymVal();
unsigned StartIdx = SimpVect.size();
SimpVect.push_back(ThisAddend);
// The inner loop collects addends sharing same symbolic-value, and these
// addends will be later on folded into a single addend. Following above
// example, if the symbolic value "y" is being processed, the inner loop
// will collect two addends "<b1,y>" and "<b2,Y>". These two addends will
// be later on folded into "<b1+b2, y>".
//
for (unsigned SameSymIdx = SymIdx + 1;
SameSymIdx < AddendNum; SameSymIdx++) {
const FAddend *T = Addends[SameSymIdx];
if (T && T->getSymVal() == Val) {
// Set null such that next iteration of the outer loop will not process
// this addend again.
Addends[SameSymIdx] = nullptr;
SimpVect.push_back(T);
}
}
// If multiple addends share same symbolic value, fold them together.
if (StartIdx + 1 != SimpVect.size()) {
FAddend &R = TmpResult[NextTmpIdx ++];
R = *SimpVect[StartIdx];
for (unsigned Idx = StartIdx + 1; Idx < SimpVect.size(); Idx++)
R += *SimpVect[Idx];
// Pop all addends being folded and push the resulting folded addend.
SimpVect.resize(StartIdx);
if (Val) {
if (!R.isZero()) {
SimpVect.push_back(&R);
}
} else {
// Don't push constant addend at this time. It will be the last element
// of <SimpVect>.
ConstAdd = &R;
}
}
}
assert((NextTmpIdx <= array_lengthof(TmpResult) + 1) &&
"out-of-bound access");
if (ConstAdd)
SimpVect.push_back(ConstAdd);
Value *Result;
if (!SimpVect.empty())
Result = createNaryFAdd(SimpVect, InstrQuota);
else {
// The addition is folded to 0.0.
Result = ConstantFP::get(Instr->getType(), 0.0);
}
return Result;
}
Value *FAddCombine::createNaryFAdd
(const AddendVect &Opnds, unsigned InstrQuota) {
assert(!Opnds.empty() && "Expect at least one addend");
// Step 1: Check if the # of instructions needed exceeds the quota.
//
unsigned InstrNeeded = calcInstrNumber(Opnds);
if (InstrNeeded > InstrQuota)
return nullptr;
initCreateInstNum();
// step 2: Emit the N-ary addition.
// Note that at most three instructions are involved in Fadd-InstCombine: the
// addition in question, and at most two neighboring instructions.
// The resulting optimized addition should have at least one less instruction
// than the original addition expression tree. This implies that the resulting
// N-ary addition has at most two instructions, and we don't need to worry
// about tree-height when constructing the N-ary addition.
Value *LastVal = nullptr;
bool LastValNeedNeg = false;
// Iterate the addends, creating fadd/fsub using adjacent two addends.
for (AddendVect::const_iterator I = Opnds.begin(), E = Opnds.end();
I != E; I++) {
bool NeedNeg;
Value *V = createAddendVal(**I, NeedNeg);
if (!LastVal) {
LastVal = V;
LastValNeedNeg = NeedNeg;
continue;
}
if (LastValNeedNeg == NeedNeg) {
LastVal = createFAdd(LastVal, V);
continue;
}
if (LastValNeedNeg)
LastVal = createFSub(V, LastVal);
else
LastVal = createFSub(LastVal, V);
LastValNeedNeg = false;
}
if (LastValNeedNeg) {
LastVal = createFNeg(LastVal);
}
#ifndef NDEBUG
assert(CreateInstrNum == InstrNeeded &&
"Inconsistent in instruction numbers");
#endif
return LastVal;
}
Value *FAddCombine::createFSub(Value *Opnd0, Value *Opnd1) {
Value *V = Builder->CreateFSub(Opnd0, Opnd1);
if (Instruction *I = dyn_cast<Instruction>(V))
createInstPostProc(I);
return V;
}
Value *FAddCombine::createFNeg(Value *V) {
Value *Zero = cast<Value>(ConstantFP::getZeroValueForNegation(V->getType()));
Value *NewV = createFSub(Zero, V);
if (Instruction *I = dyn_cast<Instruction>(NewV))
createInstPostProc(I, true); // fneg's don't receive instruction numbers.
return NewV;
}
Value *FAddCombine::createFAdd(Value *Opnd0, Value *Opnd1) {
Value *V = Builder->CreateFAdd(Opnd0, Opnd1);
if (Instruction *I = dyn_cast<Instruction>(V))
createInstPostProc(I);
return V;
}
Value *FAddCombine::createFMul(Value *Opnd0, Value *Opnd1) {
Value *V = Builder->CreateFMul(Opnd0, Opnd1);
if (Instruction *I = dyn_cast<Instruction>(V))
createInstPostProc(I);
return V;
}
Value *FAddCombine::createFDiv(Value *Opnd0, Value *Opnd1) {
Value *V = Builder->CreateFDiv(Opnd0, Opnd1);
if (Instruction *I = dyn_cast<Instruction>(V))
createInstPostProc(I);
return V;
}
void FAddCombine::createInstPostProc(Instruction *NewInstr, bool NoNumber) {
NewInstr->setDebugLoc(Instr->getDebugLoc());
// Keep track of the number of instruction created.
if (!NoNumber)
incCreateInstNum();
// Propagate fast-math flags
NewInstr->setFastMathFlags(Instr->getFastMathFlags());
}
// Return the number of instruction needed to emit the N-ary addition.
// NOTE: Keep this function in sync with createAddendVal().
unsigned FAddCombine::calcInstrNumber(const AddendVect &Opnds) {
unsigned OpndNum = Opnds.size();
unsigned InstrNeeded = OpndNum - 1;
// The number of addends in the form of "(-1)*x".
unsigned NegOpndNum = 0;
// Adjust the number of instructions needed to emit the N-ary add.
for (AddendVect::const_iterator I = Opnds.begin(), E = Opnds.end();
I != E; I++) {
const FAddend *Opnd = *I;
if (Opnd->isConstant())
continue;
const FAddendCoef &CE = Opnd->getCoef();
if (CE.isMinusOne() || CE.isMinusTwo())
NegOpndNum++;
// Let the addend be "c * x". If "c == +/-1", the value of the addend
// is immediately available; otherwise, it needs exactly one instruction
// to evaluate the value.
if (!CE.isMinusOne() && !CE.isOne())
InstrNeeded++;
}
if (NegOpndNum == OpndNum)
InstrNeeded++;
return InstrNeeded;
}
// Input Addend Value NeedNeg(output)
// ================================================================
// Constant C C false
// <+/-1, V> V coefficient is -1
// <2/-2, V> "fadd V, V" coefficient is -2
// <C, V> "fmul V, C" false
//
// NOTE: Keep this function in sync with FAddCombine::calcInstrNumber.
Value *FAddCombine::createAddendVal(const FAddend &Opnd, bool &NeedNeg) {
const FAddendCoef &Coeff = Opnd.getCoef();
if (Opnd.isConstant()) {
NeedNeg = false;
return Coeff.getValue(Instr->getType());
}
Value *OpndVal = Opnd.getSymVal();
if (Coeff.isMinusOne() || Coeff.isOne()) {
NeedNeg = Coeff.isMinusOne();
return OpndVal;
}
if (Coeff.isTwo() || Coeff.isMinusTwo()) {
NeedNeg = Coeff.isMinusTwo();
return createFAdd(OpndVal, OpndVal);
}
NeedNeg = false;
return createFMul(OpndVal, Coeff.getValue(Instr->getType()));
}
// If one of the operands only has one non-zero bit, and if the other
// operand has a known-zero bit in a more significant place than it (not
// including the sign bit) the ripple may go up to and fill the zero, but
// won't change the sign. For example, (X & ~4) + 1.
static bool checkRippleForAdd(const APInt &Op0KnownZero,
const APInt &Op1KnownZero) {
APInt Op1MaybeOne = ~Op1KnownZero;
// Make sure that one of the operand has at most one bit set to 1.
if (Op1MaybeOne.countPopulation() != 1)
return false;
// Find the most significant known 0 other than the sign bit.
int BitWidth = Op0KnownZero.getBitWidth();
APInt Op0KnownZeroTemp(Op0KnownZero);
Op0KnownZeroTemp.clearBit(BitWidth - 1);
int Op0ZeroPosition = BitWidth - Op0KnownZeroTemp.countLeadingZeros() - 1;
int Op1OnePosition = BitWidth - Op1MaybeOne.countLeadingZeros() - 1;
assert(Op1OnePosition >= 0);
// This also covers the case of no known zero, since in that case
// Op0ZeroPosition is -1.
return Op0ZeroPosition >= Op1OnePosition;
}
/// WillNotOverflowSignedAdd - Return true if we can prove that:
/// (sext (add LHS, RHS)) === (add (sext LHS), (sext RHS))
/// This basically requires proving that the add in the original type would not
/// overflow to change the sign bit or have a carry out.
bool InstCombiner::WillNotOverflowSignedAdd(Value *LHS, Value *RHS,
Instruction &CxtI) {
// There are different heuristics we can use for this. Here are some simple
// ones.
// If LHS and RHS each have at least two sign bits, the addition will look
// like
//
// XX..... +
// YY.....
//
// If the carry into the most significant position is 0, X and Y can't both
// be 1 and therefore the carry out of the addition is also 0.
//
// If the carry into the most significant position is 1, X and Y can't both
// be 0 and therefore the carry out of the addition is also 1.
//
// Since the carry into the most significant position is always equal to
// the carry out of the addition, there is no signed overflow.
if (ComputeNumSignBits(LHS, 0, &CxtI) > 1 &&
ComputeNumSignBits(RHS, 0, &CxtI) > 1)
return true;
unsigned BitWidth = LHS->getType()->getScalarSizeInBits();
APInt LHSKnownZero(BitWidth, 0);
APInt LHSKnownOne(BitWidth, 0);
computeKnownBits(LHS, LHSKnownZero, LHSKnownOne, 0, &CxtI);
APInt RHSKnownZero(BitWidth, 0);
APInt RHSKnownOne(BitWidth, 0);
computeKnownBits(RHS, RHSKnownZero, RHSKnownOne, 0, &CxtI);
// Addition of two 2's compliment numbers having opposite signs will never
// overflow.
if ((LHSKnownOne[BitWidth - 1] && RHSKnownZero[BitWidth - 1]) ||
(LHSKnownZero[BitWidth - 1] && RHSKnownOne[BitWidth - 1]))
return true;
// Check if carry bit of addition will not cause overflow.
if (checkRippleForAdd(LHSKnownZero, RHSKnownZero))
return true;
if (checkRippleForAdd(RHSKnownZero, LHSKnownZero))
return true;
return false;
}
/// \brief Return true if we can prove that:
/// (sub LHS, RHS) === (sub nsw LHS, RHS)
/// This basically requires proving that the add in the original type would not
/// overflow to change the sign bit or have a carry out.
/// TODO: Handle this for Vectors.
bool InstCombiner::WillNotOverflowSignedSub(Value *LHS, Value *RHS,
Instruction &CxtI) {
// If LHS and RHS each have at least two sign bits, the subtraction
// cannot overflow.
if (ComputeNumSignBits(LHS, 0, &CxtI) > 1 &&
ComputeNumSignBits(RHS, 0, &CxtI) > 1)
return true;
unsigned BitWidth = LHS->getType()->getScalarSizeInBits();
APInt LHSKnownZero(BitWidth, 0);
APInt LHSKnownOne(BitWidth, 0);
computeKnownBits(LHS, LHSKnownZero, LHSKnownOne, 0, &CxtI);
APInt RHSKnownZero(BitWidth, 0);
APInt RHSKnownOne(BitWidth, 0);
computeKnownBits(RHS, RHSKnownZero, RHSKnownOne, 0, &CxtI);
// Subtraction of two 2's compliment numbers having identical signs will
// never overflow.
if ((LHSKnownOne[BitWidth - 1] && RHSKnownOne[BitWidth - 1]) ||
(LHSKnownZero[BitWidth - 1] && RHSKnownZero[BitWidth - 1]))
return true;
// TODO: implement logic similar to checkRippleForAdd
return false;
}
/// \brief Return true if we can prove that:
/// (sub LHS, RHS) === (sub nuw LHS, RHS)
bool InstCombiner::WillNotOverflowUnsignedSub(Value *LHS, Value *RHS,
Instruction &CxtI) {
// If the LHS is negative and the RHS is non-negative, no unsigned wrap.
bool LHSKnownNonNegative, LHSKnownNegative;
bool RHSKnownNonNegative, RHSKnownNegative;
ComputeSignBit(LHS, LHSKnownNonNegative, LHSKnownNegative, /*Depth=*/0,
&CxtI);
ComputeSignBit(RHS, RHSKnownNonNegative, RHSKnownNegative, /*Depth=*/0,
&CxtI);
if (LHSKnownNegative && RHSKnownNonNegative)
return true;
return false;
}
// Checks if any operand is negative and we can convert add to sub.
// This function checks for following negative patterns
// ADD(XOR(OR(Z, NOT(C)), C)), 1) == NEG(AND(Z, C))
// ADD(XOR(AND(Z, C), C), 1) == NEG(OR(Z, ~C))
// XOR(AND(Z, C), (C + 1)) == NEG(OR(Z, ~C)) if C is even
static Value *checkForNegativeOperand(BinaryOperator &I,
InstCombiner::BuilderTy *Builder) {
Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
// This function creates 2 instructions to replace ADD, we need at least one
// of LHS or RHS to have one use to ensure benefit in transform.
if (!LHS->hasOneUse() && !RHS->hasOneUse())
return nullptr;
Value *X = nullptr, *Y = nullptr, *Z = nullptr;
const APInt *C1 = nullptr, *C2 = nullptr;
// if ONE is on other side, swap
if (match(RHS, m_Add(m_Value(X), m_One())))
std::swap(LHS, RHS);
if (match(LHS, m_Add(m_Value(X), m_One()))) {
// if XOR on other side, swap
if (match(RHS, m_Xor(m_Value(Y), m_APInt(C1))))
std::swap(X, RHS);
if (match(X, m_Xor(m_Value(Y), m_APInt(C1)))) {
// X = XOR(Y, C1), Y = OR(Z, C2), C2 = NOT(C1) ==> X == NOT(AND(Z, C1))
// ADD(ADD(X, 1), RHS) == ADD(X, ADD(RHS, 1)) == SUB(RHS, AND(Z, C1))
if (match(Y, m_Or(m_Value(Z), m_APInt(C2))) && (*C2 == ~(*C1))) {
Value *NewAnd = Builder->CreateAnd(Z, *C1);
return Builder->CreateSub(RHS, NewAnd, "sub");
} else if (match(Y, m_And(m_Value(Z), m_APInt(C2))) && (*C1 == *C2)) {
// X = XOR(Y, C1), Y = AND(Z, C2), C2 == C1 ==> X == NOT(OR(Z, ~C1))
// ADD(ADD(X, 1), RHS) == ADD(X, ADD(RHS, 1)) == SUB(RHS, OR(Z, ~C1))
Value *NewOr = Builder->CreateOr(Z, ~(*C1));
return Builder->CreateSub(RHS, NewOr, "sub");
}
}
}
// Restore LHS and RHS
LHS = I.getOperand(0);
RHS = I.getOperand(1);
// if XOR is on other side, swap
if (match(RHS, m_Xor(m_Value(Y), m_APInt(C1))))
std::swap(LHS, RHS);
// C2 is ODD
// LHS = XOR(Y, C1), Y = AND(Z, C2), C1 == (C2 + 1) => LHS == NEG(OR(Z, ~C2))
// ADD(LHS, RHS) == SUB(RHS, OR(Z, ~C2))
if (match(LHS, m_Xor(m_Value(Y), m_APInt(C1))))
if (C1->countTrailingZeros() == 0)
if (match(Y, m_And(m_Value(Z), m_APInt(C2))) && *C1 == (*C2 + 1)) {
Value *NewOr = Builder->CreateOr(Z, ~(*C2));
return Builder->CreateSub(RHS, NewOr, "sub");
}
return nullptr;
}
Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
bool Changed = SimplifyAssociativeOrCommutative(I);
Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifyAddInst(LHS, RHS, I.hasNoSignedWrap(),
I.hasNoUnsignedWrap(), DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
// (A*B)+(A*C) -> A*(B+C) etc
if (Value *V = SimplifyUsingDistributiveLaws(I))
return ReplaceInstUsesWith(I, V);
if (ConstantInt *CI = dyn_cast<ConstantInt>(RHS)) {
// X + (signbit) --> X ^ signbit
const APInt &Val = CI->getValue();
if (Val.isSignBit())
return BinaryOperator::CreateXor(LHS, RHS);
// See if SimplifyDemandedBits can simplify this. This handles stuff like
// (X & 254)+1 -> (X&254)|1
if (SimplifyDemandedInstructionBits(I))
return &I;
// zext(bool) + C -> bool ? C + 1 : C
if (ZExtInst *ZI = dyn_cast<ZExtInst>(LHS))
if (ZI->getSrcTy()->isIntegerTy(1))
return SelectInst::Create(ZI->getOperand(0), AddOne(CI), CI);
Value *XorLHS = nullptr; ConstantInt *XorRHS = nullptr;
if (match(LHS, m_Xor(m_Value(XorLHS), m_ConstantInt(XorRHS)))) {
uint32_t TySizeBits = I.getType()->getScalarSizeInBits();
const APInt &RHSVal = CI->getValue();
unsigned ExtendAmt = 0;
// If we have ADD(XOR(AND(X, 0xFF), 0x80), 0xF..F80), it's a sext.
// If we have ADD(XOR(AND(X, 0xFF), 0xF..F80), 0x80), it's a sext.
if (XorRHS->getValue() == -RHSVal) {
if (RHSVal.isPowerOf2())
ExtendAmt = TySizeBits - RHSVal.logBase2() - 1;
else if (XorRHS->getValue().isPowerOf2())
ExtendAmt = TySizeBits - XorRHS->getValue().logBase2() - 1;
}
if (ExtendAmt) {
APInt Mask = APInt::getHighBitsSet(TySizeBits, ExtendAmt);
if (!MaskedValueIsZero(XorLHS, Mask, 0, &I))
ExtendAmt = 0;
}
if (ExtendAmt) {
Constant *ShAmt = ConstantInt::get(I.getType(), ExtendAmt);
Value *NewShl = Builder->CreateShl(XorLHS, ShAmt, "sext");
return BinaryOperator::CreateAShr(NewShl, ShAmt);
}
// If this is a xor that was canonicalized from a sub, turn it back into
// a sub and fuse this add with it.
if (LHS->hasOneUse() && (XorRHS->getValue()+1).isPowerOf2()) {
IntegerType *IT = cast<IntegerType>(I.getType());
APInt LHSKnownOne(IT->getBitWidth(), 0);
APInt LHSKnownZero(IT->getBitWidth(), 0);
computeKnownBits(XorLHS, LHSKnownZero, LHSKnownOne, 0, &I);
if ((XorRHS->getValue() | LHSKnownZero).isAllOnesValue())
return BinaryOperator::CreateSub(ConstantExpr::getAdd(XorRHS, CI),
XorLHS);
}
// (X + signbit) + C could have gotten canonicalized to (X ^ signbit) + C,
// transform them into (X + (signbit ^ C))
if (XorRHS->getValue().isSignBit())
return BinaryOperator::CreateAdd(XorLHS,
ConstantExpr::getXor(XorRHS, CI));
}
}
if (isa<Constant>(RHS) && isa<PHINode>(LHS))
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
if (I.getType()->getScalarType()->isIntegerTy(1))
return BinaryOperator::CreateXor(LHS, RHS);
// X + X --> X << 1
if (LHS == RHS) {
BinaryOperator *New =
BinaryOperator::CreateShl(LHS, ConstantInt::get(I.getType(), 1));
New->setHasNoSignedWrap(I.hasNoSignedWrap());
New->setHasNoUnsignedWrap(I.hasNoUnsignedWrap());
return New;
}
// -A + B --> B - A
// -A + -B --> -(A + B)
if (Value *LHSV = dyn_castNegVal(LHS)) {
if (!isa<Constant>(RHS))
if (Value *RHSV = dyn_castNegVal(RHS)) {
Value *NewAdd = Builder->CreateAdd(LHSV, RHSV, "sum");
return BinaryOperator::CreateNeg(NewAdd);
}
return BinaryOperator::CreateSub(RHS, LHSV);
}
// A + -B --> A - B
if (!isa<Constant>(RHS))
if (Value *V = dyn_castNegVal(RHS))
return BinaryOperator::CreateSub(LHS, V);
if (Value *V = checkForNegativeOperand(I, Builder))
return ReplaceInstUsesWith(I, V);
// A+B --> A|B iff A and B have no bits set in common.
if (haveNoCommonBitsSet(LHS, RHS, DL, AC, &I, DT))
return BinaryOperator::CreateOr(LHS, RHS);
if (Constant *CRHS = dyn_cast<Constant>(RHS)) {
Value *X;
if (match(LHS, m_Not(m_Value(X)))) // ~X + C --> (C-1) - X
return BinaryOperator::CreateSub(SubOne(CRHS), X);
}
if (ConstantInt *CRHS = dyn_cast<ConstantInt>(RHS)) {
// (X & FF00) + xx00 -> (X+xx00) & FF00
Value *X;
ConstantInt *C2;
if (LHS->hasOneUse() &&
match(LHS, m_And(m_Value(X), m_ConstantInt(C2))) &&
CRHS->getValue() == (CRHS->getValue() & C2->getValue())) {
// See if all bits from the first bit set in the Add RHS up are included
// in the mask. First, get the rightmost bit.
const APInt &AddRHSV = CRHS->getValue();
// Form a mask of all bits from the lowest bit added through the top.
APInt AddRHSHighBits(~((AddRHSV & -AddRHSV)-1));
// See if the and mask includes all of these bits.
APInt AddRHSHighBitsAnd(AddRHSHighBits & C2->getValue());
if (AddRHSHighBits == AddRHSHighBitsAnd) {
// Okay, the xform is safe. Insert the new add pronto.
Value *NewAdd = Builder->CreateAdd(X, CRHS, LHS->getName());
return BinaryOperator::CreateAnd(NewAdd, C2);
}
}
// Try to fold constant add into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(LHS))
if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
}
// add (select X 0 (sub n A)) A --> select X A n
{
SelectInst *SI = dyn_cast<SelectInst>(LHS);
Value *A = RHS;
if (!SI) {
SI = dyn_cast<SelectInst>(RHS);
A = LHS;
}
if (SI && SI->hasOneUse()) {
Value *TV = SI->getTrueValue();
Value *FV = SI->getFalseValue();
Value *N;
// Can we fold the add into the argument of the select?
// We check both true and false select arguments for a matching subtract.
if (match(FV, m_Zero()) && match(TV, m_Sub(m_Value(N), m_Specific(A))))
// Fold the add into the true select value.
return SelectInst::Create(SI->getCondition(), N, A);
if (match(TV, m_Zero()) && match(FV, m_Sub(m_Value(N), m_Specific(A))))
// Fold the add into the false select value.
return SelectInst::Create(SI->getCondition(), A, N);
}
}
// Check for (add (sext x), y), see if we can merge this into an
// integer add followed by a sext.
if (SExtInst *LHSConv = dyn_cast<SExtInst>(LHS)) {
// (add (sext x), cst) --> (sext (add x, cst'))
if (ConstantInt *RHSC = dyn_cast<ConstantInt>(RHS)) {
Constant *CI =
ConstantExpr::getTrunc(RHSC, LHSConv->getOperand(0)->getType());
if (LHSConv->hasOneUse() &&
ConstantExpr::getSExt(CI, I.getType()) == RHSC &&
WillNotOverflowSignedAdd(LHSConv->getOperand(0), CI, I)) {
// Insert the new, smaller add.
Value *NewAdd = Builder->CreateNSWAdd(LHSConv->getOperand(0),
CI, "addconv");
return new SExtInst(NewAdd, I.getType());
}
}
// (add (sext x), (sext y)) --> (sext (add int x, y))
if (SExtInst *RHSConv = dyn_cast<SExtInst>(RHS)) {
// Only do this if x/y have the same type, if at last one of them has a
// single use (so we don't increase the number of sexts), and if the
// integer add will not overflow.
if (LHSConv->getOperand(0)->getType() ==
RHSConv->getOperand(0)->getType() &&
(LHSConv->hasOneUse() || RHSConv->hasOneUse()) &&
WillNotOverflowSignedAdd(LHSConv->getOperand(0),
RHSConv->getOperand(0), I)) {
// Insert the new integer add.
Value *NewAdd = Builder->CreateNSWAdd(LHSConv->getOperand(0),
RHSConv->getOperand(0), "addconv");
return new SExtInst(NewAdd, I.getType());
}
}
}
// (add (xor A, B) (and A, B)) --> (or A, B)
{
Value *A = nullptr, *B = nullptr;
if (match(RHS, m_Xor(m_Value(A), m_Value(B))) &&
(match(LHS, m_And(m_Specific(A), m_Specific(B))) ||
match(LHS, m_And(m_Specific(B), m_Specific(A)))))
return BinaryOperator::CreateOr(A, B);
if (match(LHS, m_Xor(m_Value(A), m_Value(B))) &&
(match(RHS, m_And(m_Specific(A), m_Specific(B))) ||
match(RHS, m_And(m_Specific(B), m_Specific(A)))))
return BinaryOperator::CreateOr(A, B);
}
// (add (or A, B) (and A, B)) --> (add A, B)
{
Value *A = nullptr, *B = nullptr;
if (match(RHS, m_Or(m_Value(A), m_Value(B))) &&
(match(LHS, m_And(m_Specific(A), m_Specific(B))) ||
match(LHS, m_And(m_Specific(B), m_Specific(A))))) {
auto *New = BinaryOperator::CreateAdd(A, B);
New->setHasNoSignedWrap(I.hasNoSignedWrap());
New->setHasNoUnsignedWrap(I.hasNoUnsignedWrap());
return New;
}
if (match(LHS, m_Or(m_Value(A), m_Value(B))) &&
(match(RHS, m_And(m_Specific(A), m_Specific(B))) ||
match(RHS, m_And(m_Specific(B), m_Specific(A))))) {
auto *New = BinaryOperator::CreateAdd(A, B);
New->setHasNoSignedWrap(I.hasNoSignedWrap());
New->setHasNoUnsignedWrap(I.hasNoUnsignedWrap());
return New;
}
}
// TODO(jingyue): Consider WillNotOverflowSignedAdd and
// WillNotOverflowUnsignedAdd to reduce the number of invocations of
// computeKnownBits.
if (!I.hasNoSignedWrap() && WillNotOverflowSignedAdd(LHS, RHS, I)) {
Changed = true;
I.setHasNoSignedWrap(true);
}
if (!I.hasNoUnsignedWrap() &&
computeOverflowForUnsignedAdd(LHS, RHS, &I) ==
OverflowResult::NeverOverflows) {
Changed = true;
I.setHasNoUnsignedWrap(true);
}
return Changed ? &I : nullptr;
}
Instruction *InstCombiner::visitFAdd(BinaryOperator &I) {
bool Changed = SimplifyAssociativeOrCommutative(I);
Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V =
SimplifyFAddInst(LHS, RHS, I.getFastMathFlags(), DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
if (isa<Constant>(RHS)) {
if (isa<PHINode>(LHS))
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
if (SelectInst *SI = dyn_cast<SelectInst>(LHS))
if (Instruction *NV = FoldOpIntoSelect(I, SI))
return NV;
}
// -A + B --> B - A
// -A + -B --> -(A + B)
if (Value *LHSV = dyn_castFNegVal(LHS)) {
Instruction *RI = BinaryOperator::CreateFSub(RHS, LHSV);
RI->copyFastMathFlags(&I);
return RI;
}
// A + -B --> A - B
if (!isa<Constant>(RHS))
if (Value *V = dyn_castFNegVal(RHS)) {
Instruction *RI = BinaryOperator::CreateFSub(LHS, V);
RI->copyFastMathFlags(&I);
return RI;
}
// Check for (fadd double (sitofp x), y), see if we can merge this into an
// integer add followed by a promotion.
if (SIToFPInst *LHSConv = dyn_cast<SIToFPInst>(LHS)) {
// (fadd double (sitofp x), fpcst) --> (sitofp (add int x, intcst))
// ... if the constant fits in the integer value. This is useful for things
// like (double)(x & 1234) + 4.0 -> (double)((X & 1234)+4) which no longer
// requires a constant pool load, and generally allows the add to be better
// instcombined.
if (ConstantFP *CFP = dyn_cast<ConstantFP>(RHS)) {
Constant *CI =
ConstantExpr::getFPToSI(CFP, LHSConv->getOperand(0)->getType());
if (LHSConv->hasOneUse() &&
ConstantExpr::getSIToFP(CI, I.getType()) == CFP &&
WillNotOverflowSignedAdd(LHSConv->getOperand(0), CI, I)) {
// Insert the new integer add.
Value *NewAdd = Builder->CreateNSWAdd(LHSConv->getOperand(0),
CI, "addconv");
return new SIToFPInst(NewAdd, I.getType());
}
}
// (fadd double (sitofp x), (sitofp y)) --> (sitofp (add int x, y))
if (SIToFPInst *RHSConv = dyn_cast<SIToFPInst>(RHS)) {
// Only do this if x/y have the same type, if at last one of them has a
// single use (so we don't increase the number of int->fp conversions),
// and if the integer add will not overflow.
if (LHSConv->getOperand(0)->getType() ==
RHSConv->getOperand(0)->getType() &&
(LHSConv->hasOneUse() || RHSConv->hasOneUse()) &&
WillNotOverflowSignedAdd(LHSConv->getOperand(0),
RHSConv->getOperand(0), I)) {
// Insert the new integer add.
Value *NewAdd = Builder->CreateNSWAdd(LHSConv->getOperand(0),
RHSConv->getOperand(0),"addconv");
return new SIToFPInst(NewAdd, I.getType());
}
}
}
// select C, 0, B + select C, A, 0 -> select C, A, B
{
Value *A1, *B1, *C1, *A2, *B2, *C2;
if (match(LHS, m_Select(m_Value(C1), m_Value(A1), m_Value(B1))) &&
match(RHS, m_Select(m_Value(C2), m_Value(A2), m_Value(B2)))) {
if (C1 == C2) {
Constant *Z1=nullptr, *Z2=nullptr;
Value *A, *B, *C=C1;
if (match(A1, m_AnyZero()) && match(B2, m_AnyZero())) {
Z1 = dyn_cast<Constant>(A1); A = A2;
Z2 = dyn_cast<Constant>(B2); B = B1;
} else if (match(B1, m_AnyZero()) && match(A2, m_AnyZero())) {
Z1 = dyn_cast<Constant>(B1); B = B2;
Z2 = dyn_cast<Constant>(A2); A = A1;
}
if (Z1 && Z2 &&
(I.hasNoSignedZeros() ||
(Z1->isNegativeZeroValue() && Z2->isNegativeZeroValue()))) {
return SelectInst::Create(C, A, B);
}
}
}
}
if (I.hasUnsafeAlgebra()) {
if (Value *V = FAddCombine(Builder).simplify(&I))
return ReplaceInstUsesWith(I, V);
}
return Changed ? &I : nullptr;
}
/// Optimize pointer differences into the same array into a size. Consider:
/// &A[10] - &A[0]: we should compile this to "10". LHS/RHS are the pointer
/// operands to the ptrtoint instructions for the LHS/RHS of the subtract.
///
Value *InstCombiner::OptimizePointerDifference(Value *LHS, Value *RHS,
Type *Ty) {
// If LHS is a gep based on RHS or RHS is a gep based on LHS, we can optimize
// this.
bool Swapped = false;
GEPOperator *GEP1 = nullptr, *GEP2 = nullptr;
// For now we require one side to be the base pointer "A" or a constant
// GEP derived from it.
if (GEPOperator *LHSGEP = dyn_cast<GEPOperator>(LHS)) {
// (gep X, ...) - X
if (LHSGEP->getOperand(0) == RHS) {
GEP1 = LHSGEP;
Swapped = false;
} else if (GEPOperator *RHSGEP = dyn_cast<GEPOperator>(RHS)) {
// (gep X, ...) - (gep X, ...)
if (LHSGEP->getOperand(0)->stripPointerCasts() ==
RHSGEP->getOperand(0)->stripPointerCasts()) {
GEP2 = RHSGEP;
GEP1 = LHSGEP;
Swapped = false;
}
}
}
if (GEPOperator *RHSGEP = dyn_cast<GEPOperator>(RHS)) {
// X - (gep X, ...)
if (RHSGEP->getOperand(0) == LHS) {
GEP1 = RHSGEP;
Swapped = true;
} else if (GEPOperator *LHSGEP = dyn_cast<GEPOperator>(LHS)) {
// (gep X, ...) - (gep X, ...)
if (RHSGEP->getOperand(0)->stripPointerCasts() ==
LHSGEP->getOperand(0)->stripPointerCasts()) {
GEP2 = LHSGEP;
GEP1 = RHSGEP;
Swapped = true;
}
}
}
// Avoid duplicating the arithmetic if GEP2 has non-constant indices and
// multiple users.
if (!GEP1 ||
(GEP2 && !GEP2->hasAllConstantIndices() && !GEP2->hasOneUse()))
return nullptr;
// Emit the offset of the GEP and an intptr_t.
Value *Result = EmitGEPOffset(GEP1);
// If we had a constant expression GEP on the other side offsetting the
// pointer, subtract it from the offset we have.
if (GEP2) {
Value *Offset = EmitGEPOffset(GEP2);
Result = Builder->CreateSub(Result, Offset);
}
// If we have p - gep(p, ...) then we have to negate the result.
if (Swapped)
Result = Builder->CreateNeg(Result, "diff.neg");
return Builder->CreateIntCast(Result, Ty, true);
}
Instruction *InstCombiner::visitSub(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifySubInst(Op0, Op1, I.hasNoSignedWrap(),
I.hasNoUnsignedWrap(), DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
// (A*B)-(A*C) -> A*(B-C) etc
if (Value *V = SimplifyUsingDistributiveLaws(I))
return ReplaceInstUsesWith(I, V);
// If this is a 'B = x-(-A)', change to B = x+A.
if (Value *V = dyn_castNegVal(Op1)) {
BinaryOperator *Res = BinaryOperator::CreateAdd(Op0, V);
if (const auto *BO = dyn_cast<BinaryOperator>(Op1)) {
assert(BO->getOpcode() == Instruction::Sub &&
"Expected a subtraction operator!");
if (BO->hasNoSignedWrap() && I.hasNoSignedWrap())
Res->setHasNoSignedWrap(true);
} else {
if (cast<Constant>(Op1)->isNotMinSignedValue() && I.hasNoSignedWrap())
Res->setHasNoSignedWrap(true);
}
return Res;
}
if (I.getType()->isIntegerTy(1))
return BinaryOperator::CreateXor(Op0, Op1);
// Replace (-1 - A) with (~A).
if (match(Op0, m_AllOnes()))
return BinaryOperator::CreateNot(Op1);
if (Constant *C = dyn_cast<Constant>(Op0)) {
// C - ~X == X + (1+C)
Value *X = nullptr;
if (match(Op1, m_Not(m_Value(X))))
return BinaryOperator::CreateAdd(X, AddOne(C));
// Try to fold constant sub into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op1))
if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
// C-(X+C2) --> (C-C2)-X
Constant *C2;
if (match(Op1, m_Add(m_Value(X), m_Constant(C2))))
return BinaryOperator::CreateSub(ConstantExpr::getSub(C, C2), X);
if (SimplifyDemandedInstructionBits(I))
return &I;
// Fold (sub 0, (zext bool to B)) --> (sext bool to B)
if (C->isNullValue() && match(Op1, m_ZExt(m_Value(X))))
if (X->getType()->getScalarType()->isIntegerTy(1))
return CastInst::CreateSExtOrBitCast(X, Op1->getType());
// Fold (sub 0, (sext bool to B)) --> (zext bool to B)
if (C->isNullValue() && match(Op1, m_SExt(m_Value(X))))
if (X->getType()->getScalarType()->isIntegerTy(1))
return CastInst::CreateZExtOrBitCast(X, Op1->getType());
}
if (ConstantInt *C = dyn_cast<ConstantInt>(Op0)) {
// -(X >>u 31) -> (X >>s 31)
// -(X >>s 31) -> (X >>u 31)
if (C->isZero()) {
Value *X;
ConstantInt *CI;
if (match(Op1, m_LShr(m_Value(X), m_ConstantInt(CI))) &&
// Verify we are shifting out everything but the sign bit.
CI->getValue() == I.getType()->getPrimitiveSizeInBits() - 1)
return BinaryOperator::CreateAShr(X, CI);
if (match(Op1, m_AShr(m_Value(X), m_ConstantInt(CI))) &&
// Verify we are shifting out everything but the sign bit.
CI->getValue() == I.getType()->getPrimitiveSizeInBits() - 1)
return BinaryOperator::CreateLShr(X, CI);
}
// Turn this into a xor if LHS is 2^n-1 and the remaining bits are known
// zero.
APInt IntVal = C->getValue();
if ((IntVal + 1).isPowerOf2()) {
unsigned BitWidth = I.getType()->getScalarSizeInBits();
APInt KnownZero(BitWidth, 0);
APInt KnownOne(BitWidth, 0);
computeKnownBits(&I, KnownZero, KnownOne, 0, &I);
if ((IntVal | KnownZero).isAllOnesValue()) {
return BinaryOperator::CreateXor(Op1, C);
}
}
}
{
Value *Y;
// X-(X+Y) == -Y X-(Y+X) == -Y
if (match(Op1, m_Add(m_Specific(Op0), m_Value(Y))) ||
match(Op1, m_Add(m_Value(Y), m_Specific(Op0))))
return BinaryOperator::CreateNeg(Y);
// (X-Y)-X == -Y
if (match(Op0, m_Sub(m_Specific(Op1), m_Value(Y))))
return BinaryOperator::CreateNeg(Y);
}
// (sub (or A, B) (xor A, B)) --> (and A, B)
{
Value *A = nullptr, *B = nullptr;
if (match(Op1, m_Xor(m_Value(A), m_Value(B))) &&
(match(Op0, m_Or(m_Specific(A), m_Specific(B))) ||
match(Op0, m_Or(m_Specific(B), m_Specific(A)))))
return BinaryOperator::CreateAnd(A, B);
}
// (sub (select (a, c, b)), (select (a, d, b))) -> (select (a, (sub c, d), 0))
// (sub (select (a, b, c)), (select (a, b, d))) -> (select (a, 0, (sub c, d)))
if (auto *SI0 = dyn_cast<SelectInst>(Op0)) {
if (auto *SI1 = dyn_cast<SelectInst>(Op1)) {
if (SI0->getCondition() == SI1->getCondition()) {
if (Value *V = SimplifySubInst(
SI0->getFalseValue(), SI1->getFalseValue(), I.hasNoSignedWrap(),
I.hasNoUnsignedWrap(), DL, TLI, DT, AC))
return SelectInst::Create(
SI0->getCondition(),
Builder->CreateSub(SI0->getTrueValue(), SI1->getTrueValue(), "",
/*HasNUW=*/I.hasNoUnsignedWrap(),
/*HasNSW=*/I.hasNoSignedWrap()),
V);
if (Value *V = SimplifySubInst(SI0->getTrueValue(), SI1->getTrueValue(),
I.hasNoSignedWrap(),
I.hasNoUnsignedWrap(), DL, TLI, DT, AC))
return SelectInst::Create(
SI0->getCondition(), V,
Builder->CreateSub(SI0->getFalseValue(), SI1->getFalseValue(), "",
/*HasNUW=*/I.hasNoUnsignedWrap(),
/*HasNSW=*/I.hasNoSignedWrap()));
}
}
}
if (Op0->hasOneUse()) {
Value *Y = nullptr;
// ((X | Y) - X) --> (~X & Y)
if (match(Op0, m_Or(m_Value(Y), m_Specific(Op1))) ||
match(Op0, m_Or(m_Specific(Op1), m_Value(Y))))
return BinaryOperator::CreateAnd(
Y, Builder->CreateNot(Op1, Op1->getName() + ".not"));
}
if (Op1->hasOneUse()) {
Value *X = nullptr, *Y = nullptr, *Z = nullptr;
Constant *C = nullptr;
Constant *CI = nullptr;
// (X - (Y - Z)) --> (X + (Z - Y)).
if (match(Op1, m_Sub(m_Value(Y), m_Value(Z))))
return BinaryOperator::CreateAdd(Op0,
Builder->CreateSub(Z, Y, Op1->getName()));
// (X - (X & Y)) --> (X & ~Y)
//
if (match(Op1, m_And(m_Value(Y), m_Specific(Op0))) ||
match(Op1, m_And(m_Specific(Op0), m_Value(Y))))
return BinaryOperator::CreateAnd(Op0,
Builder->CreateNot(Y, Y->getName() + ".not"));
// 0 - (X sdiv C) -> (X sdiv -C) provided the negation doesn't overflow.
if (match(Op1, m_SDiv(m_Value(X), m_Constant(C))) && match(Op0, m_Zero()) &&
C->isNotMinSignedValue() && !C->isOneValue())
return BinaryOperator::CreateSDiv(X, ConstantExpr::getNeg(C));
// 0 - (X << Y) -> (-X << Y) when X is freely negatable.
if (match(Op1, m_Shl(m_Value(X), m_Value(Y))) && match(Op0, m_Zero()))
if (Value *XNeg = dyn_castNegVal(X))
return BinaryOperator::CreateShl(XNeg, Y);
// X - A*-B -> X + A*B
// X - -A*B -> X + A*B
Value *A, *B;
if (match(Op1, m_Mul(m_Value(A), m_Neg(m_Value(B)))) ||
match(Op1, m_Mul(m_Neg(m_Value(A)), m_Value(B))))
return BinaryOperator::CreateAdd(Op0, Builder->CreateMul(A, B));
// X - A*CI -> X + A*-CI
// X - CI*A -> X + A*-CI
if (match(Op1, m_Mul(m_Value(A), m_Constant(CI))) ||
match(Op1, m_Mul(m_Constant(CI), m_Value(A)))) {
Value *NewMul = Builder->CreateMul(A, ConstantExpr::getNeg(CI));
return BinaryOperator::CreateAdd(Op0, NewMul);
}
}
// Optimize pointer differences into the same array into a size. Consider:
// &A[10] - &A[0]: we should compile this to "10".
Value *LHSOp, *RHSOp;
if (match(Op0, m_PtrToInt(m_Value(LHSOp))) &&
match(Op1, m_PtrToInt(m_Value(RHSOp))))
if (Value *Res = OptimizePointerDifference(LHSOp, RHSOp, I.getType()))
return ReplaceInstUsesWith(I, Res);
// trunc(p)-trunc(q) -> trunc(p-q)
if (match(Op0, m_Trunc(m_PtrToInt(m_Value(LHSOp)))) &&
match(Op1, m_Trunc(m_PtrToInt(m_Value(RHSOp)))))
if (Value *Res = OptimizePointerDifference(LHSOp, RHSOp, I.getType()))
return ReplaceInstUsesWith(I, Res);
bool Changed = false;
if (!I.hasNoSignedWrap() && WillNotOverflowSignedSub(Op0, Op1, I)) {
Changed = true;
I.setHasNoSignedWrap(true);
}
if (!I.hasNoUnsignedWrap() && WillNotOverflowUnsignedSub(Op0, Op1, I)) {
Changed = true;
I.setHasNoUnsignedWrap(true);
}
return Changed ? &I : nullptr;
}
Instruction *InstCombiner::visitFSub(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V =
SimplifyFSubInst(Op0, Op1, I.getFastMathFlags(), DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
// fsub nsz 0, X ==> fsub nsz -0.0, X
if (I.getFastMathFlags().noSignedZeros() && match(Op0, m_Zero())) {
// Subtraction from -0.0 is the canonical form of fneg.
Instruction *NewI = BinaryOperator::CreateFNeg(Op1);
NewI->copyFastMathFlags(&I);
return NewI;
}
if (isa<Constant>(Op0))
if (SelectInst *SI = dyn_cast<SelectInst>(Op1))
if (Instruction *NV = FoldOpIntoSelect(I, SI))
return NV;
// If this is a 'B = x-(-A)', change to B = x+A, potentially looking
// through FP extensions/truncations along the way.
if (Value *V = dyn_castFNegVal(Op1)) {
Instruction *NewI = BinaryOperator::CreateFAdd(Op0, V);
NewI->copyFastMathFlags(&I);
return NewI;
}
if (FPTruncInst *FPTI = dyn_cast<FPTruncInst>(Op1)) {
if (Value *V = dyn_castFNegVal(FPTI->getOperand(0))) {
Value *NewTrunc = Builder->CreateFPTrunc(V, I.getType());
Instruction *NewI = BinaryOperator::CreateFAdd(Op0, NewTrunc);
NewI->copyFastMathFlags(&I);
return NewI;
}
} else if (FPExtInst *FPEI = dyn_cast<FPExtInst>(Op1)) {
if (Value *V = dyn_castFNegVal(FPEI->getOperand(0))) {
Value *NewExt = Builder->CreateFPExt(V, I.getType());
Instruction *NewI = BinaryOperator::CreateFAdd(Op0, NewExt);
NewI->copyFastMathFlags(&I);
return NewI;
}
}
if (I.hasUnsafeAlgebra()) {
if (Value *V = FAddCombine(Builder).simplify(&I))
return ReplaceInstUsesWith(I, V);
}
return nullptr;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/InstCombinePHI.cpp | //===- InstCombinePHI.cpp -------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the visitPHINode function.
//
//===----------------------------------------------------------------------===//
#include "InstCombineInternal.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/Analysis/InstructionSimplify.h"
using namespace llvm;
#define DEBUG_TYPE "instcombine"
/// If we have something like phi [add (a,b), add(a,c)] and if a/b/c and the
/// adds all have a single use, turn this into a phi and a single binop.
Instruction *InstCombiner::FoldPHIArgBinOpIntoPHI(PHINode &PN) {
Instruction *FirstInst = cast<Instruction>(PN.getIncomingValue(0));
assert(isa<BinaryOperator>(FirstInst) || isa<CmpInst>(FirstInst));
unsigned Opc = FirstInst->getOpcode();
Value *LHSVal = FirstInst->getOperand(0);
Value *RHSVal = FirstInst->getOperand(1);
Type *LHSType = LHSVal->getType();
Type *RHSType = RHSVal->getType();
bool isNUW = false, isNSW = false, isExact = false;
if (OverflowingBinaryOperator *BO =
dyn_cast<OverflowingBinaryOperator>(FirstInst)) {
isNUW = BO->hasNoUnsignedWrap();
isNSW = BO->hasNoSignedWrap();
} else if (PossiblyExactOperator *PEO =
dyn_cast<PossiblyExactOperator>(FirstInst))
isExact = PEO->isExact();
// Scan to see if all operands are the same opcode, and all have one use.
for (unsigned i = 1; i != PN.getNumIncomingValues(); ++i) {
Instruction *I = dyn_cast<Instruction>(PN.getIncomingValue(i));
if (!I || I->getOpcode() != Opc || !I->hasOneUse() ||
// Verify type of the LHS matches so we don't fold cmp's of different
// types.
I->getOperand(0)->getType() != LHSType ||
I->getOperand(1)->getType() != RHSType)
return nullptr;
// If they are CmpInst instructions, check their predicates
if (CmpInst *CI = dyn_cast<CmpInst>(I))
if (CI->getPredicate() != cast<CmpInst>(FirstInst)->getPredicate())
return nullptr;
if (isNUW)
isNUW = cast<OverflowingBinaryOperator>(I)->hasNoUnsignedWrap();
if (isNSW)
isNSW = cast<OverflowingBinaryOperator>(I)->hasNoSignedWrap();
if (isExact)
isExact = cast<PossiblyExactOperator>(I)->isExact();
// Keep track of which operand needs a phi node.
if (I->getOperand(0) != LHSVal) LHSVal = nullptr;
if (I->getOperand(1) != RHSVal) RHSVal = nullptr;
}
// If both LHS and RHS would need a PHI, don't do this transformation,
// because it would increase the number of PHIs entering the block,
// which leads to higher register pressure. This is especially
// bad when the PHIs are in the header of a loop.
if (!LHSVal && !RHSVal)
return nullptr;
// Otherwise, this is safe to transform!
Value *InLHS = FirstInst->getOperand(0);
Value *InRHS = FirstInst->getOperand(1);
PHINode *NewLHS = nullptr, *NewRHS = nullptr;
if (!LHSVal) {
NewLHS = PHINode::Create(LHSType, PN.getNumIncomingValues(),
FirstInst->getOperand(0)->getName() + ".pn");
NewLHS->addIncoming(InLHS, PN.getIncomingBlock(0));
InsertNewInstBefore(NewLHS, PN);
LHSVal = NewLHS;
}
if (!RHSVal) {
NewRHS = PHINode::Create(RHSType, PN.getNumIncomingValues(),
FirstInst->getOperand(1)->getName() + ".pn");
NewRHS->addIncoming(InRHS, PN.getIncomingBlock(0));
InsertNewInstBefore(NewRHS, PN);
RHSVal = NewRHS;
}
// Add all operands to the new PHIs.
if (NewLHS || NewRHS) {
for (unsigned i = 1, e = PN.getNumIncomingValues(); i != e; ++i) {
Instruction *InInst = cast<Instruction>(PN.getIncomingValue(i));
if (NewLHS) {
Value *NewInLHS = InInst->getOperand(0);
NewLHS->addIncoming(NewInLHS, PN.getIncomingBlock(i));
}
if (NewRHS) {
Value *NewInRHS = InInst->getOperand(1);
NewRHS->addIncoming(NewInRHS, PN.getIncomingBlock(i));
}
}
}
if (CmpInst *CIOp = dyn_cast<CmpInst>(FirstInst)) {
CmpInst *NewCI = CmpInst::Create(CIOp->getOpcode(), CIOp->getPredicate(),
LHSVal, RHSVal);
NewCI->setDebugLoc(FirstInst->getDebugLoc());
return NewCI;
}
BinaryOperator *BinOp = cast<BinaryOperator>(FirstInst);
BinaryOperator *NewBinOp =
BinaryOperator::Create(BinOp->getOpcode(), LHSVal, RHSVal);
if (isNUW) NewBinOp->setHasNoUnsignedWrap();
if (isNSW) NewBinOp->setHasNoSignedWrap();
if (isExact) NewBinOp->setIsExact();
NewBinOp->setDebugLoc(FirstInst->getDebugLoc());
return NewBinOp;
}
Instruction *InstCombiner::FoldPHIArgGEPIntoPHI(PHINode &PN) {
GetElementPtrInst *FirstInst =cast<GetElementPtrInst>(PN.getIncomingValue(0));
SmallVector<Value*, 16> FixedOperands(FirstInst->op_begin(),
FirstInst->op_end());
// This is true if all GEP bases are allocas and if all indices into them are
// constants.
bool AllBasePointersAreAllocas = true;
// We don't want to replace this phi if the replacement would require
// more than one phi, which leads to higher register pressure. This is
// especially bad when the PHIs are in the header of a loop.
bool NeededPhi = false;
bool AllInBounds = true;
// Scan to see if all operands are the same opcode, and all have one use.
for (unsigned i = 1; i != PN.getNumIncomingValues(); ++i) {
GetElementPtrInst *GEP= dyn_cast<GetElementPtrInst>(PN.getIncomingValue(i));
if (!GEP || !GEP->hasOneUse() || GEP->getType() != FirstInst->getType() ||
GEP->getNumOperands() != FirstInst->getNumOperands())
return nullptr;
AllInBounds &= GEP->isInBounds();
// Keep track of whether or not all GEPs are of alloca pointers.
if (AllBasePointersAreAllocas &&
(!isa<AllocaInst>(GEP->getOperand(0)) ||
!GEP->hasAllConstantIndices()))
AllBasePointersAreAllocas = false;
// Compare the operand lists.
for (unsigned op = 0, e = FirstInst->getNumOperands(); op != e; ++op) {
if (FirstInst->getOperand(op) == GEP->getOperand(op))
continue;
// Don't merge two GEPs when two operands differ (introducing phi nodes)
// if one of the PHIs has a constant for the index. The index may be
// substantially cheaper to compute for the constants, so making it a
// variable index could pessimize the path. This also handles the case
// for struct indices, which must always be constant.
if (isa<ConstantInt>(FirstInst->getOperand(op)) ||
isa<ConstantInt>(GEP->getOperand(op)))
return nullptr;
if (FirstInst->getOperand(op)->getType() !=GEP->getOperand(op)->getType())
return nullptr;
// If we already needed a PHI for an earlier operand, and another operand
// also requires a PHI, we'd be introducing more PHIs than we're
// eliminating, which increases register pressure on entry to the PHI's
// block.
if (NeededPhi)
return nullptr;
FixedOperands[op] = nullptr; // Needs a PHI.
NeededPhi = true;
}
}
// If all of the base pointers of the PHI'd GEPs are from allocas, don't
// bother doing this transformation. At best, this will just save a bit of
// offset calculation, but all the predecessors will have to materialize the
// stack address into a register anyway. We'd actually rather *clone* the
// load up into the predecessors so that we have a load of a gep of an alloca,
// which can usually all be folded into the load.
if (AllBasePointersAreAllocas)
return nullptr;
// Otherwise, this is safe to transform. Insert PHI nodes for each operand
// that is variable.
SmallVector<PHINode*, 16> OperandPhis(FixedOperands.size());
bool HasAnyPHIs = false;
for (unsigned i = 0, e = FixedOperands.size(); i != e; ++i) {
if (FixedOperands[i]) continue; // operand doesn't need a phi.
Value *FirstOp = FirstInst->getOperand(i);
PHINode *NewPN = PHINode::Create(FirstOp->getType(), e,
FirstOp->getName()+".pn");
InsertNewInstBefore(NewPN, PN);
NewPN->addIncoming(FirstOp, PN.getIncomingBlock(0));
OperandPhis[i] = NewPN;
FixedOperands[i] = NewPN;
HasAnyPHIs = true;
}
// Add all operands to the new PHIs.
if (HasAnyPHIs) {
for (unsigned i = 1, e = PN.getNumIncomingValues(); i != e; ++i) {
GetElementPtrInst *InGEP =cast<GetElementPtrInst>(PN.getIncomingValue(i));
BasicBlock *InBB = PN.getIncomingBlock(i);
for (unsigned op = 0, e = OperandPhis.size(); op != e; ++op)
if (PHINode *OpPhi = OperandPhis[op])
OpPhi->addIncoming(InGEP->getOperand(op), InBB);
}
}
Value *Base = FixedOperands[0];
GetElementPtrInst *NewGEP =
GetElementPtrInst::Create(FirstInst->getSourceElementType(), Base,
makeArrayRef(FixedOperands).slice(1));
if (AllInBounds) NewGEP->setIsInBounds();
NewGEP->setDebugLoc(FirstInst->getDebugLoc());
return NewGEP;
}
/// Return true if we know that it is safe to sink the load out of the block
/// that defines it. This means that it must be obvious the value of the load is
/// not changed from the point of the load to the end of the block it is in.
///
/// Finally, it is safe, but not profitable, to sink a load targeting a
/// non-address-taken alloca. Doing so will cause us to not promote the alloca
/// to a register.
static bool isSafeAndProfitableToSinkLoad(LoadInst *L) {
BasicBlock::iterator BBI = L, E = L->getParent()->end();
for (++BBI; BBI != E; ++BBI)
if (BBI->mayWriteToMemory())
return false;
// Check for non-address taken alloca. If not address-taken already, it isn't
// profitable to do this xform.
if (AllocaInst *AI = dyn_cast<AllocaInst>(L->getOperand(0))) {
bool isAddressTaken = false;
for (User *U : AI->users()) {
if (isa<LoadInst>(U)) continue;
if (StoreInst *SI = dyn_cast<StoreInst>(U)) {
// If storing TO the alloca, then the address isn't taken.
if (SI->getOperand(1) == AI) continue;
}
isAddressTaken = true;
break;
}
if (!isAddressTaken && AI->isStaticAlloca())
return false;
}
// If this load is a load from a GEP with a constant offset from an alloca,
// then we don't want to sink it. In its present form, it will be
// load [constant stack offset]. Sinking it will cause us to have to
// materialize the stack addresses in each predecessor in a register only to
// do a shared load from register in the successor.
if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(L->getOperand(0)))
if (AllocaInst *AI = dyn_cast<AllocaInst>(GEP->getOperand(0)))
if (AI->isStaticAlloca() && GEP->hasAllConstantIndices())
return false;
return true;
}
Instruction *InstCombiner::FoldPHIArgLoadIntoPHI(PHINode &PN) {
// HLSL Change Begin - Do not create phi on pointer.
return nullptr;
// HLSL Change End.
LoadInst *FirstLI = cast<LoadInst>(PN.getIncomingValue(0));
// FIXME: This is overconservative; this transform is allowed in some cases
// for atomic operations.
if (FirstLI->isAtomic())
return nullptr;
// When processing loads, we need to propagate two bits of information to the
// sunk load: whether it is volatile, and what its alignment is. We currently
// don't sink loads when some have their alignment specified and some don't.
// visitLoadInst will propagate an alignment onto the load when TD is around,
// and if TD isn't around, we can't handle the mixed case.
bool isVolatile = FirstLI->isVolatile();
unsigned LoadAlignment = FirstLI->getAlignment();
unsigned LoadAddrSpace = FirstLI->getPointerAddressSpace();
// We can't sink the load if the loaded value could be modified between the
// load and the PHI.
if (FirstLI->getParent() != PN.getIncomingBlock(0) ||
!isSafeAndProfitableToSinkLoad(FirstLI))
return nullptr;
// If the PHI is of volatile loads and the load block has multiple
// successors, sinking it would remove a load of the volatile value from
// the path through the other successor.
if (isVolatile &&
FirstLI->getParent()->getTerminator()->getNumSuccessors() != 1)
return nullptr;
// Check to see if all arguments are the same operation.
for (unsigned i = 1, e = PN.getNumIncomingValues(); i != e; ++i) {
LoadInst *LI = dyn_cast<LoadInst>(PN.getIncomingValue(i));
if (!LI || !LI->hasOneUse())
return nullptr;
// We can't sink the load if the loaded value could be modified between
// the load and the PHI.
if (LI->isVolatile() != isVolatile ||
LI->getParent() != PN.getIncomingBlock(i) ||
LI->getPointerAddressSpace() != LoadAddrSpace ||
!isSafeAndProfitableToSinkLoad(LI))
return nullptr;
// If some of the loads have an alignment specified but not all of them,
// we can't do the transformation.
if ((LoadAlignment != 0) != (LI->getAlignment() != 0))
return nullptr;
LoadAlignment = std::min(LoadAlignment, LI->getAlignment());
// If the PHI is of volatile loads and the load block has multiple
// successors, sinking it would remove a load of the volatile value from
// the path through the other successor.
if (isVolatile &&
LI->getParent()->getTerminator()->getNumSuccessors() != 1)
return nullptr;
}
// Okay, they are all the same operation. Create a new PHI node of the
// correct type, and PHI together all of the LHS's of the instructions.
PHINode *NewPN = PHINode::Create(FirstLI->getOperand(0)->getType(),
PN.getNumIncomingValues(),
PN.getName()+".in");
Value *InVal = FirstLI->getOperand(0);
NewPN->addIncoming(InVal, PN.getIncomingBlock(0));
// Add all operands to the new PHI.
for (unsigned i = 1, e = PN.getNumIncomingValues(); i != e; ++i) {
Value *NewInVal = cast<LoadInst>(PN.getIncomingValue(i))->getOperand(0);
if (NewInVal != InVal)
InVal = nullptr;
NewPN->addIncoming(NewInVal, PN.getIncomingBlock(i));
}
Value *PhiVal;
if (InVal) {
// The new PHI unions all of the same values together. This is really
// common, so we handle it intelligently here for compile-time speed.
PhiVal = InVal;
delete NewPN;
} else {
InsertNewInstBefore(NewPN, PN);
PhiVal = NewPN;
}
// If this was a volatile load that we are merging, make sure to loop through
// and mark all the input loads as non-volatile. If we don't do this, we will
// insert a new volatile load and the old ones will not be deletable.
if (isVolatile)
for (Value *IncValue : PN.incoming_values())
cast<LoadInst>(IncValue)->setVolatile(false);
LoadInst *NewLI = new LoadInst(PhiVal, "", isVolatile, LoadAlignment);
NewLI->setDebugLoc(FirstLI->getDebugLoc());
return NewLI;
}
/// If all operands to a PHI node are the same "unary" operator and they all are
/// only used by the PHI, PHI together their inputs, and do the operation once,
/// to the result of the PHI.
Instruction *InstCombiner::FoldPHIArgOpIntoPHI(PHINode &PN) {
Instruction *FirstInst = cast<Instruction>(PN.getIncomingValue(0));
if (isa<GetElementPtrInst>(FirstInst))
return FoldPHIArgGEPIntoPHI(PN);
if (isa<LoadInst>(FirstInst))
return FoldPHIArgLoadIntoPHI(PN);
// Scan the instruction, looking for input operations that can be folded away.
// If all input operands to the phi are the same instruction (e.g. a cast from
// the same type or "+42") we can pull the operation through the PHI, reducing
// code size and simplifying code.
Constant *ConstantOp = nullptr;
Type *CastSrcTy = nullptr;
bool isNUW = false, isNSW = false, isExact = false;
if (isa<CastInst>(FirstInst)) {
CastSrcTy = FirstInst->getOperand(0)->getType();
// Be careful about transforming integer PHIs. We don't want to pessimize
// the code by turning an i32 into an i1293.
if (PN.getType()->isIntegerTy() && CastSrcTy->isIntegerTy()) {
if (!ShouldChangeType(PN.getType(), CastSrcTy))
return nullptr;
}
} else if (isa<BinaryOperator>(FirstInst) || isa<CmpInst>(FirstInst)) {
// Can fold binop, compare or shift here if the RHS is a constant,
// otherwise call FoldPHIArgBinOpIntoPHI.
ConstantOp = dyn_cast<Constant>(FirstInst->getOperand(1));
if (!ConstantOp)
return FoldPHIArgBinOpIntoPHI(PN);
if (OverflowingBinaryOperator *BO =
dyn_cast<OverflowingBinaryOperator>(FirstInst)) {
isNUW = BO->hasNoUnsignedWrap();
isNSW = BO->hasNoSignedWrap();
} else if (PossiblyExactOperator *PEO =
dyn_cast<PossiblyExactOperator>(FirstInst))
isExact = PEO->isExact();
} else {
return nullptr; // Cannot fold this operation.
}
// Check to see if all arguments are the same operation.
for (unsigned i = 1, e = PN.getNumIncomingValues(); i != e; ++i) {
Instruction *I = dyn_cast<Instruction>(PN.getIncomingValue(i));
if (!I || !I->hasOneUse() || !I->isSameOperationAs(FirstInst))
return nullptr;
if (CastSrcTy) {
if (I->getOperand(0)->getType() != CastSrcTy)
return nullptr; // Cast operation must match.
} else if (I->getOperand(1) != ConstantOp) {
return nullptr;
}
if (isNUW)
isNUW = cast<OverflowingBinaryOperator>(I)->hasNoUnsignedWrap();
if (isNSW)
isNSW = cast<OverflowingBinaryOperator>(I)->hasNoSignedWrap();
if (isExact)
isExact = cast<PossiblyExactOperator>(I)->isExact();
}
// Okay, they are all the same operation. Create a new PHI node of the
// correct type, and PHI together all of the LHS's of the instructions.
PHINode *NewPN = PHINode::Create(FirstInst->getOperand(0)->getType(),
PN.getNumIncomingValues(),
PN.getName()+".in");
Value *InVal = FirstInst->getOperand(0);
NewPN->addIncoming(InVal, PN.getIncomingBlock(0));
// Add all operands to the new PHI.
for (unsigned i = 1, e = PN.getNumIncomingValues(); i != e; ++i) {
Value *NewInVal = cast<Instruction>(PN.getIncomingValue(i))->getOperand(0);
if (NewInVal != InVal)
InVal = nullptr;
NewPN->addIncoming(NewInVal, PN.getIncomingBlock(i));
}
Value *PhiVal;
if (InVal) {
// The new PHI unions all of the same values together. This is really
// common, so we handle it intelligently here for compile-time speed.
PhiVal = InVal;
delete NewPN;
} else {
InsertNewInstBefore(NewPN, PN);
PhiVal = NewPN;
}
// Insert and return the new operation.
if (CastInst *FirstCI = dyn_cast<CastInst>(FirstInst)) {
CastInst *NewCI = CastInst::Create(FirstCI->getOpcode(), PhiVal,
PN.getType());
NewCI->setDebugLoc(FirstInst->getDebugLoc());
return NewCI;
}
if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(FirstInst)) {
BinOp = BinaryOperator::Create(BinOp->getOpcode(), PhiVal, ConstantOp);
if (isNUW) BinOp->setHasNoUnsignedWrap();
if (isNSW) BinOp->setHasNoSignedWrap();
if (isExact) BinOp->setIsExact();
BinOp->setDebugLoc(FirstInst->getDebugLoc());
return BinOp;
}
CmpInst *CIOp = cast<CmpInst>(FirstInst);
CmpInst *NewCI = CmpInst::Create(CIOp->getOpcode(), CIOp->getPredicate(),
PhiVal, ConstantOp);
NewCI->setDebugLoc(FirstInst->getDebugLoc());
return NewCI;
}
/// Return true if this PHI node is only used by a PHI node cycle that is dead.
static bool DeadPHICycle(PHINode *PN,
SmallPtrSetImpl<PHINode*> &PotentiallyDeadPHIs) {
if (PN->use_empty()) return true;
if (!PN->hasOneUse()) return false;
// Remember this node, and if we find the cycle, return.
if (!PotentiallyDeadPHIs.insert(PN).second)
return true;
// Don't scan crazily complex things.
if (PotentiallyDeadPHIs.size() == 16)
return false;
if (PHINode *PU = dyn_cast<PHINode>(PN->user_back()))
return DeadPHICycle(PU, PotentiallyDeadPHIs);
return false;
}
/// Return true if this phi node is always equal to NonPhiInVal.
/// This happens with mutually cyclic phi nodes like:
/// z = some value; x = phi (y, z); y = phi (x, z)
static bool PHIsEqualValue(PHINode *PN, Value *NonPhiInVal,
SmallPtrSetImpl<PHINode*> &ValueEqualPHIs) {
// See if we already saw this PHI node.
if (!ValueEqualPHIs.insert(PN).second)
return true;
// Don't scan crazily complex things.
if (ValueEqualPHIs.size() == 16)
return false;
// Scan the operands to see if they are either phi nodes or are equal to
// the value.
for (Value *Op : PN->incoming_values()) {
if (PHINode *OpPN = dyn_cast<PHINode>(Op)) {
if (!PHIsEqualValue(OpPN, NonPhiInVal, ValueEqualPHIs))
return false;
} else if (Op != NonPhiInVal)
return false;
}
return true;
}
namespace {
struct PHIUsageRecord {
unsigned PHIId; // The ID # of the PHI (something determinstic to sort on)
unsigned Shift; // The amount shifted.
Instruction *Inst; // The trunc instruction.
PHIUsageRecord(unsigned pn, unsigned Sh, Instruction *User)
: PHIId(pn), Shift(Sh), Inst(User) {}
bool operator<(const PHIUsageRecord &RHS) const {
if (PHIId < RHS.PHIId) return true;
if (PHIId > RHS.PHIId) return false;
if (Shift < RHS.Shift) return true;
if (Shift > RHS.Shift) return false;
return Inst->getType()->getPrimitiveSizeInBits() <
RHS.Inst->getType()->getPrimitiveSizeInBits();
}
};
struct LoweredPHIRecord {
PHINode *PN; // The PHI that was lowered.
unsigned Shift; // The amount shifted.
unsigned Width; // The width extracted.
LoweredPHIRecord(PHINode *pn, unsigned Sh, Type *Ty)
: PN(pn), Shift(Sh), Width(Ty->getPrimitiveSizeInBits()) {}
// Ctor form used by DenseMap.
LoweredPHIRecord(PHINode *pn, unsigned Sh)
: PN(pn), Shift(Sh), Width(0) {}
};
}
namespace llvm {
template<>
struct DenseMapInfo<LoweredPHIRecord> {
static inline LoweredPHIRecord getEmptyKey() {
return LoweredPHIRecord(nullptr, 0);
}
static inline LoweredPHIRecord getTombstoneKey() {
return LoweredPHIRecord(nullptr, 1);
}
static unsigned getHashValue(const LoweredPHIRecord &Val) {
return DenseMapInfo<PHINode*>::getHashValue(Val.PN) ^ (Val.Shift>>3) ^
(Val.Width>>3);
}
static bool isEqual(const LoweredPHIRecord &LHS,
const LoweredPHIRecord &RHS) {
return LHS.PN == RHS.PN && LHS.Shift == RHS.Shift &&
LHS.Width == RHS.Width;
}
};
}
/// This is an integer PHI and we know that it has an illegal type: see if it is
/// only used by trunc or trunc(lshr) operations. If so, we split the PHI into
/// the various pieces being extracted. This sort of thing is introduced when
/// SROA promotes an aggregate to large integer values.
///
/// TODO: The user of the trunc may be an bitcast to float/double/vector or an
/// inttoptr. We should produce new PHIs in the right type.
///
Instruction *InstCombiner::SliceUpIllegalIntegerPHI(PHINode &FirstPhi) {
// PHIUsers - Keep track of all of the truncated values extracted from a set
// of PHIs, along with their offset. These are the things we want to rewrite.
SmallVector<PHIUsageRecord, 16> PHIUsers;
// PHIs are often mutually cyclic, so we keep track of a whole set of PHI
// nodes which are extracted from. PHIsToSlice is a set we use to avoid
// revisiting PHIs, PHIsInspected is a ordered list of PHIs that we need to
// check the uses of (to ensure they are all extracts).
SmallVector<PHINode*, 8> PHIsToSlice;
SmallPtrSet<PHINode*, 8> PHIsInspected;
PHIsToSlice.push_back(&FirstPhi);
PHIsInspected.insert(&FirstPhi);
for (unsigned PHIId = 0; PHIId != PHIsToSlice.size(); ++PHIId) {
PHINode *PN = PHIsToSlice[PHIId];
// Scan the input list of the PHI. If any input is an invoke, and if the
// input is defined in the predecessor, then we won't be split the critical
// edge which is required to insert a truncate. Because of this, we have to
// bail out.
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
InvokeInst *II = dyn_cast<InvokeInst>(PN->getIncomingValue(i));
if (!II) continue;
if (II->getParent() != PN->getIncomingBlock(i))
continue;
// If we have a phi, and if it's directly in the predecessor, then we have
// a critical edge where we need to put the truncate. Since we can't
// split the edge in instcombine, we have to bail out.
return nullptr;
}
for (User *U : PN->users()) {
Instruction *UserI = cast<Instruction>(U);
// If the user is a PHI, inspect its uses recursively.
if (PHINode *UserPN = dyn_cast<PHINode>(UserI)) {
if (PHIsInspected.insert(UserPN).second)
PHIsToSlice.push_back(UserPN);
continue;
}
// Truncates are always ok.
if (isa<TruncInst>(UserI)) {
PHIUsers.push_back(PHIUsageRecord(PHIId, 0, UserI));
continue;
}
// Otherwise it must be a lshr which can only be used by one trunc.
if (UserI->getOpcode() != Instruction::LShr ||
!UserI->hasOneUse() || !isa<TruncInst>(UserI->user_back()) ||
!isa<ConstantInt>(UserI->getOperand(1)))
return nullptr;
unsigned Shift = cast<ConstantInt>(UserI->getOperand(1))->getZExtValue();
PHIUsers.push_back(PHIUsageRecord(PHIId, Shift, UserI->user_back()));
}
}
// If we have no users, they must be all self uses, just nuke the PHI.
if (PHIUsers.empty())
return ReplaceInstUsesWith(FirstPhi, UndefValue::get(FirstPhi.getType()));
// If this phi node is transformable, create new PHIs for all the pieces
// extracted out of it. First, sort the users by their offset and size.
array_pod_sort(PHIUsers.begin(), PHIUsers.end());
DEBUG(dbgs() << "SLICING UP PHI: " << FirstPhi << '\n';
for (unsigned i = 1, e = PHIsToSlice.size(); i != e; ++i)
dbgs() << "AND USER PHI #" << i << ": " << *PHIsToSlice[i] << '\n';
);
// PredValues - This is a temporary used when rewriting PHI nodes. It is
// hoisted out here to avoid construction/destruction thrashing.
DenseMap<BasicBlock*, Value*> PredValues;
// ExtractedVals - Each new PHI we introduce is saved here so we don't
// introduce redundant PHIs.
DenseMap<LoweredPHIRecord, PHINode*> ExtractedVals;
for (unsigned UserI = 0, UserE = PHIUsers.size(); UserI != UserE; ++UserI) {
unsigned PHIId = PHIUsers[UserI].PHIId;
PHINode *PN = PHIsToSlice[PHIId];
unsigned Offset = PHIUsers[UserI].Shift;
Type *Ty = PHIUsers[UserI].Inst->getType();
PHINode *EltPHI;
// If we've already lowered a user like this, reuse the previously lowered
// value.
if ((EltPHI = ExtractedVals[LoweredPHIRecord(PN, Offset, Ty)]) == nullptr) {
// Otherwise, Create the new PHI node for this user.
EltPHI = PHINode::Create(Ty, PN->getNumIncomingValues(),
PN->getName()+".off"+Twine(Offset), PN);
assert(EltPHI->getType() != PN->getType() &&
"Truncate didn't shrink phi?");
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
BasicBlock *Pred = PN->getIncomingBlock(i);
Value *&PredVal = PredValues[Pred];
// If we already have a value for this predecessor, reuse it.
if (PredVal) {
EltPHI->addIncoming(PredVal, Pred);
continue;
}
// Handle the PHI self-reuse case.
Value *InVal = PN->getIncomingValue(i);
if (InVal == PN) {
PredVal = EltPHI;
EltPHI->addIncoming(PredVal, Pred);
continue;
}
if (PHINode *InPHI = dyn_cast<PHINode>(PN)) {
// If the incoming value was a PHI, and if it was one of the PHIs we
// already rewrote it, just use the lowered value.
if (Value *Res = ExtractedVals[LoweredPHIRecord(InPHI, Offset, Ty)]) {
PredVal = Res;
EltPHI->addIncoming(PredVal, Pred);
continue;
}
}
// Otherwise, do an extract in the predecessor.
Builder->SetInsertPoint(Pred, Pred->getTerminator());
Value *Res = InVal;
if (Offset)
Res = Builder->CreateLShr(Res, ConstantInt::get(InVal->getType(),
Offset), "extract");
Res = Builder->CreateTrunc(Res, Ty, "extract.t");
PredVal = Res;
EltPHI->addIncoming(Res, Pred);
// If the incoming value was a PHI, and if it was one of the PHIs we are
// rewriting, we will ultimately delete the code we inserted. This
// means we need to revisit that PHI to make sure we extract out the
// needed piece.
if (PHINode *OldInVal = dyn_cast<PHINode>(PN->getIncomingValue(i)))
if (PHIsInspected.count(OldInVal)) {
unsigned RefPHIId = std::find(PHIsToSlice.begin(),PHIsToSlice.end(),
OldInVal)-PHIsToSlice.begin();
PHIUsers.push_back(PHIUsageRecord(RefPHIId, Offset,
cast<Instruction>(Res)));
++UserE;
}
}
PredValues.clear();
DEBUG(dbgs() << " Made element PHI for offset " << Offset << ": "
<< *EltPHI << '\n');
ExtractedVals[LoweredPHIRecord(PN, Offset, Ty)] = EltPHI;
}
// Replace the use of this piece with the PHI node.
ReplaceInstUsesWith(*PHIUsers[UserI].Inst, EltPHI);
}
// Replace all the remaining uses of the PHI nodes (self uses and the lshrs)
// with undefs.
Value *Undef = UndefValue::get(FirstPhi.getType());
for (unsigned i = 1, e = PHIsToSlice.size(); i != e; ++i)
ReplaceInstUsesWith(*PHIsToSlice[i], Undef);
return ReplaceInstUsesWith(FirstPhi, Undef);
}
// PHINode simplification
//
Instruction *InstCombiner::visitPHINode(PHINode &PN) {
if (Value *V = SimplifyInstruction(&PN, DL, TLI, DT, AC))
return ReplaceInstUsesWith(PN, V);
// If all PHI operands are the same operation, pull them through the PHI,
// reducing code size.
if (isa<Instruction>(PN.getIncomingValue(0)) &&
isa<Instruction>(PN.getIncomingValue(1)) &&
cast<Instruction>(PN.getIncomingValue(0))->getOpcode() ==
cast<Instruction>(PN.getIncomingValue(1))->getOpcode() &&
// FIXME: The hasOneUse check will fail for PHIs that use the value more
// than themselves more than once.
PN.getIncomingValue(0)->hasOneUse())
if (Instruction *Result = FoldPHIArgOpIntoPHI(PN))
return Result;
// If this is a trivial cycle in the PHI node graph, remove it. Basically, if
// this PHI only has a single use (a PHI), and if that PHI only has one use (a
// PHI)... break the cycle.
if (PN.hasOneUse()) {
Instruction *PHIUser = cast<Instruction>(PN.user_back());
if (PHINode *PU = dyn_cast<PHINode>(PHIUser)) {
SmallPtrSet<PHINode*, 16> PotentiallyDeadPHIs;
PotentiallyDeadPHIs.insert(&PN);
if (DeadPHICycle(PU, PotentiallyDeadPHIs))
return ReplaceInstUsesWith(PN, UndefValue::get(PN.getType()));
}
// If this phi has a single use, and if that use just computes a value for
// the next iteration of a loop, delete the phi. This occurs with unused
// induction variables, e.g. "for (int j = 0; ; ++j);". Detecting this
// common case here is good because the only other things that catch this
// are induction variable analysis (sometimes) and ADCE, which is only run
// late.
if (PHIUser->hasOneUse() &&
(isa<BinaryOperator>(PHIUser) || isa<GetElementPtrInst>(PHIUser)) &&
PHIUser->user_back() == &PN) {
return ReplaceInstUsesWith(PN, UndefValue::get(PN.getType()));
}
}
// We sometimes end up with phi cycles that non-obviously end up being the
// same value, for example:
// z = some value; x = phi (y, z); y = phi (x, z)
// where the phi nodes don't necessarily need to be in the same block. Do a
// quick check to see if the PHI node only contains a single non-phi value, if
// so, scan to see if the phi cycle is actually equal to that value.
{
unsigned InValNo = 0, NumIncomingVals = PN.getNumIncomingValues();
// Scan for the first non-phi operand.
while (InValNo != NumIncomingVals &&
isa<PHINode>(PN.getIncomingValue(InValNo)))
++InValNo;
if (InValNo != NumIncomingVals) {
Value *NonPhiInVal = PN.getIncomingValue(InValNo);
// Scan the rest of the operands to see if there are any conflicts, if so
// there is no need to recursively scan other phis.
for (++InValNo; InValNo != NumIncomingVals; ++InValNo) {
Value *OpVal = PN.getIncomingValue(InValNo);
if (OpVal != NonPhiInVal && !isa<PHINode>(OpVal))
break;
}
// If we scanned over all operands, then we have one unique value plus
// phi values. Scan PHI nodes to see if they all merge in each other or
// the value.
if (InValNo == NumIncomingVals) {
SmallPtrSet<PHINode*, 16> ValueEqualPHIs;
if (PHIsEqualValue(&PN, NonPhiInVal, ValueEqualPHIs))
return ReplaceInstUsesWith(PN, NonPhiInVal);
}
}
}
// If there are multiple PHIs, sort their operands so that they all list
// the blocks in the same order. This will help identical PHIs be eliminated
// by other passes. Other passes shouldn't depend on this for correctness
// however.
PHINode *FirstPN = cast<PHINode>(PN.getParent()->begin());
if (&PN != FirstPN)
for (unsigned i = 0, e = FirstPN->getNumIncomingValues(); i != e; ++i) {
BasicBlock *BBA = PN.getIncomingBlock(i);
BasicBlock *BBB = FirstPN->getIncomingBlock(i);
if (BBA != BBB) {
Value *VA = PN.getIncomingValue(i);
unsigned j = PN.getBasicBlockIndex(BBB);
Value *VB = PN.getIncomingValue(j);
PN.setIncomingBlock(i, BBB);
PN.setIncomingValue(i, VB);
PN.setIncomingBlock(j, BBA);
PN.setIncomingValue(j, VA);
// NOTE: Instcombine normally would want us to "return &PN" if we
// modified any of the operands of an instruction. However, since we
// aren't adding or removing uses (just rearranging them) we don't do
// this in this case.
}
}
// If this is an integer PHI and we know that it has an illegal type, see if
// it is only used by trunc or trunc(lshr) operations. If so, we split the
// PHI into the various pieces being extracted. This sort of thing is
// introduced when SROA promotes an aggregate to a single large integer type.
if (PN.getType()->isIntegerTy() &&
!DL.isLegalInteger(PN.getType()->getPrimitiveSizeInBits()))
if (Instruction *Res = SliceUpIllegalIntegerPHI(PN))
return Res;
return nullptr;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/InstCombineSelect.cpp | //===- InstCombineSelect.cpp ----------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the visitSelect function.
//
//===----------------------------------------------------------------------===//
#include "InstCombineInternal.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/PatternMatch.h"
using namespace llvm;
using namespace PatternMatch;
#define DEBUG_TYPE "instcombine"
static SelectPatternFlavor
getInverseMinMaxSelectPattern(SelectPatternFlavor SPF) {
switch (SPF) {
default:
llvm_unreachable("unhandled!");
case SPF_SMIN:
return SPF_SMAX;
case SPF_UMIN:
return SPF_UMAX;
case SPF_SMAX:
return SPF_SMIN;
case SPF_UMAX:
return SPF_UMIN;
}
}
static CmpInst::Predicate getICmpPredicateForMinMax(SelectPatternFlavor SPF) {
switch (SPF) {
default:
llvm_unreachable("unhandled!");
case SPF_SMIN:
return ICmpInst::ICMP_SLT;
case SPF_UMIN:
return ICmpInst::ICMP_ULT;
case SPF_SMAX:
return ICmpInst::ICMP_SGT;
case SPF_UMAX:
return ICmpInst::ICMP_UGT;
}
}
static Value *generateMinMaxSelectPattern(InstCombiner::BuilderTy *Builder,
SelectPatternFlavor SPF, Value *A,
Value *B) {
CmpInst::Predicate Pred = getICmpPredicateForMinMax(SPF);
return Builder->CreateSelect(Builder->CreateICmp(Pred, A, B), A, B);
}
/// GetSelectFoldableOperands - We want to turn code that looks like this:
/// %C = or %A, %B
/// %D = select %cond, %C, %A
/// into:
/// %C = select %cond, %B, 0
/// %D = or %A, %C
///
/// Assuming that the specified instruction is an operand to the select, return
/// a bitmask indicating which operands of this instruction are foldable if they
/// equal the other incoming value of the select.
///
static unsigned GetSelectFoldableOperands(Instruction *I) {
switch (I->getOpcode()) {
case Instruction::Add:
case Instruction::Mul:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor:
return 3; // Can fold through either operand.
case Instruction::Sub: // Can only fold on the amount subtracted.
case Instruction::Shl: // Can only fold on the shift amount.
case Instruction::LShr:
case Instruction::AShr:
return 1;
default:
return 0; // Cannot fold
}
}
/// GetSelectFoldableConstant - For the same transformation as the previous
/// function, return the identity constant that goes into the select.
static Constant *GetSelectFoldableConstant(Instruction *I) {
switch (I->getOpcode()) {
default: llvm_unreachable("This cannot happen!");
case Instruction::Add:
case Instruction::Sub:
case Instruction::Or:
case Instruction::Xor:
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
return Constant::getNullValue(I->getType());
case Instruction::And:
return Constant::getAllOnesValue(I->getType());
case Instruction::Mul:
return ConstantInt::get(I->getType(), 1);
}
}
/// FoldSelectOpOp - Here we have (select c, TI, FI), and we know that TI and FI
/// have the same opcode and only one use each. Try to simplify this.
Instruction *InstCombiner::FoldSelectOpOp(SelectInst &SI, Instruction *TI,
Instruction *FI) {
if (TI->getNumOperands() == 1) {
// If this is a non-volatile load or a cast from the same type,
// merge.
if (TI->isCast()) {
Type *FIOpndTy = FI->getOperand(0)->getType();
if (TI->getOperand(0)->getType() != FIOpndTy)
return nullptr;
// The select condition may be a vector. We may only change the operand
// type if the vector width remains the same (and matches the condition).
Type *CondTy = SI.getCondition()->getType();
if (CondTy->isVectorTy() && (!FIOpndTy->isVectorTy() ||
CondTy->getVectorNumElements() != FIOpndTy->getVectorNumElements()))
return nullptr;
} else {
return nullptr; // unknown unary op.
}
// Fold this by inserting a select from the input values.
Value *NewSI = Builder->CreateSelect(SI.getCondition(), TI->getOperand(0),
FI->getOperand(0), SI.getName()+".v");
return CastInst::Create(Instruction::CastOps(TI->getOpcode()), NewSI,
TI->getType());
}
// Only handle binary operators here.
if (!isa<BinaryOperator>(TI))
return nullptr;
// Figure out if the operations have any operands in common.
Value *MatchOp, *OtherOpT, *OtherOpF;
bool MatchIsOpZero;
if (TI->getOperand(0) == FI->getOperand(0)) {
MatchOp = TI->getOperand(0);
OtherOpT = TI->getOperand(1);
OtherOpF = FI->getOperand(1);
MatchIsOpZero = true;
} else if (TI->getOperand(1) == FI->getOperand(1)) {
MatchOp = TI->getOperand(1);
OtherOpT = TI->getOperand(0);
OtherOpF = FI->getOperand(0);
MatchIsOpZero = false;
} else if (!TI->isCommutative()) {
return nullptr;
} else if (TI->getOperand(0) == FI->getOperand(1)) {
MatchOp = TI->getOperand(0);
OtherOpT = TI->getOperand(1);
OtherOpF = FI->getOperand(0);
MatchIsOpZero = true;
} else if (TI->getOperand(1) == FI->getOperand(0)) {
MatchOp = TI->getOperand(1);
OtherOpT = TI->getOperand(0);
OtherOpF = FI->getOperand(1);
MatchIsOpZero = true;
} else {
return nullptr;
}
// If we reach here, they do have operations in common.
Value *NewSI = Builder->CreateSelect(SI.getCondition(), OtherOpT,
OtherOpF, SI.getName()+".v");
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(TI)) {
if (MatchIsOpZero)
return BinaryOperator::Create(BO->getOpcode(), MatchOp, NewSI);
else
return BinaryOperator::Create(BO->getOpcode(), NewSI, MatchOp);
}
llvm_unreachable("Shouldn't get here");
}
static bool isSelect01(Constant *C1, Constant *C2) {
ConstantInt *C1I = dyn_cast<ConstantInt>(C1);
if (!C1I)
return false;
ConstantInt *C2I = dyn_cast<ConstantInt>(C2);
if (!C2I)
return false;
if (!C1I->isZero() && !C2I->isZero()) // One side must be zero.
return false;
return C1I->isOne() || C1I->isAllOnesValue() ||
C2I->isOne() || C2I->isAllOnesValue();
}
/// FoldSelectIntoOp - Try fold the select into one of the operands to
/// facilitate further optimization.
Instruction *InstCombiner::FoldSelectIntoOp(SelectInst &SI, Value *TrueVal,
Value *FalseVal) {
// See the comment above GetSelectFoldableOperands for a description of the
// transformation we are doing here.
if (Instruction *TVI = dyn_cast<Instruction>(TrueVal)) {
if (TVI->hasOneUse() && TVI->getNumOperands() == 2 &&
!isa<Constant>(FalseVal)) {
if (unsigned SFO = GetSelectFoldableOperands(TVI)) {
unsigned OpToFold = 0;
if ((SFO & 1) && FalseVal == TVI->getOperand(0)) {
OpToFold = 1;
} else if ((SFO & 2) && FalseVal == TVI->getOperand(1)) {
OpToFold = 2;
}
if (OpToFold) {
Constant *C = GetSelectFoldableConstant(TVI);
Value *OOp = TVI->getOperand(2-OpToFold);
// Avoid creating select between 2 constants unless it's selecting
// between 0, 1 and -1.
if (!isa<Constant>(OOp) || isSelect01(C, cast<Constant>(OOp))) {
Value *NewSel = Builder->CreateSelect(SI.getCondition(), OOp, C);
NewSel->takeName(TVI);
BinaryOperator *TVI_BO = cast<BinaryOperator>(TVI);
BinaryOperator *BO = BinaryOperator::Create(TVI_BO->getOpcode(),
FalseVal, NewSel);
if (isa<PossiblyExactOperator>(BO))
BO->setIsExact(TVI_BO->isExact());
if (isa<OverflowingBinaryOperator>(BO)) {
BO->setHasNoUnsignedWrap(TVI_BO->hasNoUnsignedWrap());
BO->setHasNoSignedWrap(TVI_BO->hasNoSignedWrap());
}
return BO;
}
}
}
}
}
if (Instruction *FVI = dyn_cast<Instruction>(FalseVal)) {
if (FVI->hasOneUse() && FVI->getNumOperands() == 2 &&
!isa<Constant>(TrueVal)) {
if (unsigned SFO = GetSelectFoldableOperands(FVI)) {
unsigned OpToFold = 0;
if ((SFO & 1) && TrueVal == FVI->getOperand(0)) {
OpToFold = 1;
} else if ((SFO & 2) && TrueVal == FVI->getOperand(1)) {
OpToFold = 2;
}
if (OpToFold) {
Constant *C = GetSelectFoldableConstant(FVI);
Value *OOp = FVI->getOperand(2-OpToFold);
// Avoid creating select between 2 constants unless it's selecting
// between 0, 1 and -1.
if (!isa<Constant>(OOp) || isSelect01(C, cast<Constant>(OOp))) {
Value *NewSel = Builder->CreateSelect(SI.getCondition(), C, OOp);
NewSel->takeName(FVI);
BinaryOperator *FVI_BO = cast<BinaryOperator>(FVI);
BinaryOperator *BO = BinaryOperator::Create(FVI_BO->getOpcode(),
TrueVal, NewSel);
if (isa<PossiblyExactOperator>(BO))
BO->setIsExact(FVI_BO->isExact());
if (isa<OverflowingBinaryOperator>(BO)) {
BO->setHasNoUnsignedWrap(FVI_BO->hasNoUnsignedWrap());
BO->setHasNoSignedWrap(FVI_BO->hasNoSignedWrap());
}
return BO;
}
}
}
}
}
return nullptr;
}
/// foldSelectICmpAndOr - We want to turn:
/// (select (icmp eq (and X, C1), 0), Y, (or Y, C2))
/// into:
/// (or (shl (and X, C1), C3), y)
/// iff:
/// C1 and C2 are both powers of 2
/// where:
/// C3 = Log(C2) - Log(C1)
///
/// This transform handles cases where:
/// 1. The icmp predicate is inverted
/// 2. The select operands are reversed
/// 3. The magnitude of C2 and C1 are flipped
static Value *foldSelectICmpAndOr(const SelectInst &SI, Value *TrueVal,
Value *FalseVal,
InstCombiner::BuilderTy *Builder) {
const ICmpInst *IC = dyn_cast<ICmpInst>(SI.getCondition());
if (!IC || !IC->isEquality() || !SI.getType()->isIntegerTy())
return nullptr;
Value *CmpLHS = IC->getOperand(0);
Value *CmpRHS = IC->getOperand(1);
if (!match(CmpRHS, m_Zero()))
return nullptr;
Value *X;
const APInt *C1;
if (!match(CmpLHS, m_And(m_Value(X), m_Power2(C1))))
return nullptr;
const APInt *C2;
bool OrOnTrueVal = false;
bool OrOnFalseVal = match(FalseVal, m_Or(m_Specific(TrueVal), m_Power2(C2)));
if (!OrOnFalseVal)
OrOnTrueVal = match(TrueVal, m_Or(m_Specific(FalseVal), m_Power2(C2)));
if (!OrOnFalseVal && !OrOnTrueVal)
return nullptr;
Value *V = CmpLHS;
Value *Y = OrOnFalseVal ? TrueVal : FalseVal;
unsigned C1Log = C1->logBase2();
unsigned C2Log = C2->logBase2();
if (C2Log > C1Log) {
V = Builder->CreateZExtOrTrunc(V, Y->getType());
V = Builder->CreateShl(V, C2Log - C1Log);
} else if (C1Log > C2Log) {
V = Builder->CreateLShr(V, C1Log - C2Log);
V = Builder->CreateZExtOrTrunc(V, Y->getType());
} else
V = Builder->CreateZExtOrTrunc(V, Y->getType());
ICmpInst::Predicate Pred = IC->getPredicate();
if ((Pred == ICmpInst::ICMP_NE && OrOnFalseVal) ||
(Pred == ICmpInst::ICMP_EQ && OrOnTrueVal))
V = Builder->CreateXor(V, *C2);
return Builder->CreateOr(V, Y);
}
/// Attempt to fold a cttz/ctlz followed by a icmp plus select into a single
/// call to cttz/ctlz with flag 'is_zero_undef' cleared.
///
/// For example, we can fold the following code sequence:
/// \code
/// %0 = tail call i32 @llvm.cttz.i32(i32 %x, i1 true)
/// %1 = icmp ne i32 %x, 0
/// %2 = select i1 %1, i32 %0, i32 32
/// \code
///
/// into:
/// %0 = tail call i32 @llvm.cttz.i32(i32 %x, i1 false)
static Value *foldSelectCttzCtlz(ICmpInst *ICI, Value *TrueVal, Value *FalseVal,
InstCombiner::BuilderTy *Builder) {
ICmpInst::Predicate Pred = ICI->getPredicate();
Value *CmpLHS = ICI->getOperand(0);
Value *CmpRHS = ICI->getOperand(1);
// Check if the condition value compares a value for equality against zero.
if (!ICI->isEquality() || !match(CmpRHS, m_Zero()))
return nullptr;
Value *Count = FalseVal;
Value *ValueOnZero = TrueVal;
if (Pred == ICmpInst::ICMP_NE)
std::swap(Count, ValueOnZero);
// Skip zero extend/truncate.
Value *V = nullptr;
if (match(Count, m_ZExt(m_Value(V))) ||
match(Count, m_Trunc(m_Value(V))))
Count = V;
// Check if the value propagated on zero is a constant number equal to the
// sizeof in bits of 'Count'.
unsigned SizeOfInBits = Count->getType()->getScalarSizeInBits();
if (!match(ValueOnZero, m_SpecificInt(SizeOfInBits)))
return nullptr;
// Check that 'Count' is a call to intrinsic cttz/ctlz. Also check that the
// input to the cttz/ctlz is used as LHS for the compare instruction.
if (match(Count, m_Intrinsic<Intrinsic::cttz>(m_Specific(CmpLHS))) ||
match(Count, m_Intrinsic<Intrinsic::ctlz>(m_Specific(CmpLHS)))) {
IntrinsicInst *II = cast<IntrinsicInst>(Count);
IRBuilder<> Builder(II);
// Explicitly clear the 'undef_on_zero' flag.
IntrinsicInst *NewI = cast<IntrinsicInst>(II->clone());
Type *Ty = NewI->getArgOperand(1)->getType();
NewI->setArgOperand(1, Constant::getNullValue(Ty));
Builder.Insert(NewI);
return Builder.CreateZExtOrTrunc(NewI, ValueOnZero->getType());
}
return nullptr;
}
/// visitSelectInstWithICmp - Visit a SelectInst that has an
/// ICmpInst as its first operand.
///
Instruction *InstCombiner::visitSelectInstWithICmp(SelectInst &SI,
ICmpInst *ICI) {
bool Changed = false;
ICmpInst::Predicate Pred = ICI->getPredicate();
Value *CmpLHS = ICI->getOperand(0);
Value *CmpRHS = ICI->getOperand(1);
Value *TrueVal = SI.getTrueValue();
Value *FalseVal = SI.getFalseValue();
// Check cases where the comparison is with a constant that
// can be adjusted to fit the min/max idiom. We may move or edit ICI
// here, so make sure the select is the only user.
if (ICI->hasOneUse())
if (ConstantInt *CI = dyn_cast<ConstantInt>(CmpRHS)) {
switch (Pred) {
default: break;
case ICmpInst::ICMP_ULT:
case ICmpInst::ICMP_SLT:
case ICmpInst::ICMP_UGT:
case ICmpInst::ICMP_SGT: {
// These transformations only work for selects over integers.
IntegerType *SelectTy = dyn_cast<IntegerType>(SI.getType());
if (!SelectTy)
break;
Constant *AdjustedRHS;
if (Pred == ICmpInst::ICMP_UGT || Pred == ICmpInst::ICMP_SGT)
AdjustedRHS = ConstantInt::get(CI->getContext(), CI->getValue() + 1);
else // (Pred == ICmpInst::ICMP_ULT || Pred == ICmpInst::ICMP_SLT)
AdjustedRHS = ConstantInt::get(CI->getContext(), CI->getValue() - 1);
// X > C ? X : C+1 --> X < C+1 ? C+1 : X
// X < C ? X : C-1 --> X > C-1 ? C-1 : X
if ((CmpLHS == TrueVal && AdjustedRHS == FalseVal) ||
(CmpLHS == FalseVal && AdjustedRHS == TrueVal))
; // Nothing to do here. Values match without any sign/zero extension.
// Types do not match. Instead of calculating this with mixed types
// promote all to the larger type. This enables scalar evolution to
// analyze this expression.
else if (CmpRHS->getType()->getScalarSizeInBits()
< SelectTy->getBitWidth()) {
Constant *sextRHS = ConstantExpr::getSExt(AdjustedRHS, SelectTy);
// X = sext x; x >s c ? X : C+1 --> X = sext x; X <s C+1 ? C+1 : X
// X = sext x; x <s c ? X : C-1 --> X = sext x; X >s C-1 ? C-1 : X
// X = sext x; x >u c ? X : C+1 --> X = sext x; X <u C+1 ? C+1 : X
// X = sext x; x <u c ? X : C-1 --> X = sext x; X >u C-1 ? C-1 : X
if (match(TrueVal, m_SExt(m_Specific(CmpLHS))) &&
sextRHS == FalseVal) {
CmpLHS = TrueVal;
AdjustedRHS = sextRHS;
} else if (match(FalseVal, m_SExt(m_Specific(CmpLHS))) &&
sextRHS == TrueVal) {
CmpLHS = FalseVal;
AdjustedRHS = sextRHS;
} else if (ICI->isUnsigned()) {
Constant *zextRHS = ConstantExpr::getZExt(AdjustedRHS, SelectTy);
// X = zext x; x >u c ? X : C+1 --> X = zext x; X <u C+1 ? C+1 : X
// X = zext x; x <u c ? X : C-1 --> X = zext x; X >u C-1 ? C-1 : X
// zext + signed compare cannot be changed:
// 0xff <s 0x00, but 0x00ff >s 0x0000
if (match(TrueVal, m_ZExt(m_Specific(CmpLHS))) &&
zextRHS == FalseVal) {
CmpLHS = TrueVal;
AdjustedRHS = zextRHS;
} else if (match(FalseVal, m_ZExt(m_Specific(CmpLHS))) &&
zextRHS == TrueVal) {
CmpLHS = FalseVal;
AdjustedRHS = zextRHS;
} else
break;
} else
break;
} else
break;
Pred = ICmpInst::getSwappedPredicate(Pred);
CmpRHS = AdjustedRHS;
std::swap(FalseVal, TrueVal);
ICI->setPredicate(Pred);
ICI->setOperand(0, CmpLHS);
ICI->setOperand(1, CmpRHS);
SI.setOperand(1, TrueVal);
SI.setOperand(2, FalseVal);
// Move ICI instruction right before the select instruction. Otherwise
// the sext/zext value may be defined after the ICI instruction uses it.
ICI->moveBefore(&SI);
Changed = true;
break;
}
}
}
// Transform (X >s -1) ? C1 : C2 --> ((X >>s 31) & (C2 - C1)) + C1
// and (X <s 0) ? C2 : C1 --> ((X >>s 31) & (C2 - C1)) + C1
// FIXME: Type and constness constraints could be lifted, but we have to
// watch code size carefully. We should consider xor instead of
// sub/add when we decide to do that.
if (IntegerType *Ty = dyn_cast<IntegerType>(CmpLHS->getType())) {
if (TrueVal->getType() == Ty) {
if (ConstantInt *Cmp = dyn_cast<ConstantInt>(CmpRHS)) {
ConstantInt *C1 = nullptr, *C2 = nullptr;
if (Pred == ICmpInst::ICMP_SGT && Cmp->isAllOnesValue()) {
C1 = dyn_cast<ConstantInt>(TrueVal);
C2 = dyn_cast<ConstantInt>(FalseVal);
} else if (Pred == ICmpInst::ICMP_SLT && Cmp->isNullValue()) {
C1 = dyn_cast<ConstantInt>(FalseVal);
C2 = dyn_cast<ConstantInt>(TrueVal);
}
if (C1 && C2) {
// This shift results in either -1 or 0.
Value *AShr = Builder->CreateAShr(CmpLHS, Ty->getBitWidth()-1);
// Check if we can express the operation with a single or.
if (C2->isAllOnesValue())
return ReplaceInstUsesWith(SI, Builder->CreateOr(AShr, C1));
Value *And = Builder->CreateAnd(AShr, C2->getValue()-C1->getValue());
return ReplaceInstUsesWith(SI, Builder->CreateAdd(And, C1));
}
}
}
}
// NOTE: if we wanted to, this is where to detect integer MIN/MAX
if (CmpRHS != CmpLHS && isa<Constant>(CmpRHS)) {
if (CmpLHS == TrueVal && Pred == ICmpInst::ICMP_EQ) {
// Transform (X == C) ? X : Y -> (X == C) ? C : Y
SI.setOperand(1, CmpRHS);
Changed = true;
} else if (CmpLHS == FalseVal && Pred == ICmpInst::ICMP_NE) {
// Transform (X != C) ? Y : X -> (X != C) ? Y : C
SI.setOperand(2, CmpRHS);
Changed = true;
}
}
{
unsigned BitWidth = DL.getTypeSizeInBits(TrueVal->getType());
APInt MinSignedValue = APInt::getSignBit(BitWidth);
Value *X;
const APInt *Y, *C;
bool TrueWhenUnset;
bool IsBitTest = false;
if (ICmpInst::isEquality(Pred) &&
match(CmpLHS, m_And(m_Value(X), m_Power2(Y))) &&
match(CmpRHS, m_Zero())) {
IsBitTest = true;
TrueWhenUnset = Pred == ICmpInst::ICMP_EQ;
} else if (Pred == ICmpInst::ICMP_SLT && match(CmpRHS, m_Zero())) {
X = CmpLHS;
Y = &MinSignedValue;
IsBitTest = true;
TrueWhenUnset = false;
} else if (Pred == ICmpInst::ICMP_SGT && match(CmpRHS, m_AllOnes())) {
X = CmpLHS;
Y = &MinSignedValue;
IsBitTest = true;
TrueWhenUnset = true;
}
if (IsBitTest) {
Value *V = nullptr;
// (X & Y) == 0 ? X : X ^ Y --> X & ~Y
if (TrueWhenUnset && TrueVal == X &&
match(FalseVal, m_Xor(m_Specific(X), m_APInt(C))) && *Y == *C)
V = Builder->CreateAnd(X, ~(*Y));
// (X & Y) != 0 ? X ^ Y : X --> X & ~Y
else if (!TrueWhenUnset && FalseVal == X &&
match(TrueVal, m_Xor(m_Specific(X), m_APInt(C))) && *Y == *C)
V = Builder->CreateAnd(X, ~(*Y));
// (X & Y) == 0 ? X ^ Y : X --> X | Y
else if (TrueWhenUnset && FalseVal == X &&
match(TrueVal, m_Xor(m_Specific(X), m_APInt(C))) && *Y == *C)
V = Builder->CreateOr(X, *Y);
// (X & Y) != 0 ? X : X ^ Y --> X | Y
else if (!TrueWhenUnset && TrueVal == X &&
match(FalseVal, m_Xor(m_Specific(X), m_APInt(C))) && *Y == *C)
V = Builder->CreateOr(X, *Y);
if (V)
return ReplaceInstUsesWith(SI, V);
}
}
if (Value *V = foldSelectICmpAndOr(SI, TrueVal, FalseVal, Builder))
return ReplaceInstUsesWith(SI, V);
if (Value *V = foldSelectCttzCtlz(ICI, TrueVal, FalseVal, Builder))
return ReplaceInstUsesWith(SI, V);
return Changed ? &SI : nullptr;
}
/// CanSelectOperandBeMappingIntoPredBlock - SI is a select whose condition is a
/// PHI node (but the two may be in different blocks). See if the true/false
/// values (V) are live in all of the predecessor blocks of the PHI. For
/// example, cases like this cannot be mapped:
///
/// X = phi [ C1, BB1], [C2, BB2]
/// Y = add
/// Z = select X, Y, 0
///
/// because Y is not live in BB1/BB2.
///
static bool CanSelectOperandBeMappingIntoPredBlock(const Value *V,
const SelectInst &SI) {
// If the value is a non-instruction value like a constant or argument, it
// can always be mapped.
const Instruction *I = dyn_cast<Instruction>(V);
if (!I) return true;
// If V is a PHI node defined in the same block as the condition PHI, we can
// map the arguments.
const PHINode *CondPHI = cast<PHINode>(SI.getCondition());
if (const PHINode *VP = dyn_cast<PHINode>(I))
if (VP->getParent() == CondPHI->getParent())
return true;
// Otherwise, if the PHI and select are defined in the same block and if V is
// defined in a different block, then we can transform it.
if (SI.getParent() == CondPHI->getParent() &&
I->getParent() != CondPHI->getParent())
return true;
// Otherwise we have a 'hard' case and we can't tell without doing more
// detailed dominator based analysis, punt.
return false;
}
/// FoldSPFofSPF - We have an SPF (e.g. a min or max) of an SPF of the form:
/// SPF2(SPF1(A, B), C)
Instruction *InstCombiner::FoldSPFofSPF(Instruction *Inner,
SelectPatternFlavor SPF1,
Value *A, Value *B,
Instruction &Outer,
SelectPatternFlavor SPF2, Value *C) {
if (C == A || C == B) {
// MAX(MAX(A, B), B) -> MAX(A, B)
// MIN(MIN(a, b), a) -> MIN(a, b)
if (SPF1 == SPF2)
return ReplaceInstUsesWith(Outer, Inner);
// MAX(MIN(a, b), a) -> a
// MIN(MAX(a, b), a) -> a
if ((SPF1 == SPF_SMIN && SPF2 == SPF_SMAX) ||
(SPF1 == SPF_SMAX && SPF2 == SPF_SMIN) ||
(SPF1 == SPF_UMIN && SPF2 == SPF_UMAX) ||
(SPF1 == SPF_UMAX && SPF2 == SPF_UMIN))
return ReplaceInstUsesWith(Outer, C);
}
if (SPF1 == SPF2) {
if (ConstantInt *CB = dyn_cast<ConstantInt>(B)) {
if (ConstantInt *CC = dyn_cast<ConstantInt>(C)) {
APInt ACB = CB->getValue();
APInt ACC = CC->getValue();
// MIN(MIN(A, 23), 97) -> MIN(A, 23)
// MAX(MAX(A, 97), 23) -> MAX(A, 97)
if ((SPF1 == SPF_UMIN && ACB.ule(ACC)) ||
(SPF1 == SPF_SMIN && ACB.sle(ACC)) ||
(SPF1 == SPF_UMAX && ACB.uge(ACC)) ||
(SPF1 == SPF_SMAX && ACB.sge(ACC)))
return ReplaceInstUsesWith(Outer, Inner);
// MIN(MIN(A, 97), 23) -> MIN(A, 23)
// MAX(MAX(A, 23), 97) -> MAX(A, 97)
if ((SPF1 == SPF_UMIN && ACB.ugt(ACC)) ||
(SPF1 == SPF_SMIN && ACB.sgt(ACC)) ||
(SPF1 == SPF_UMAX && ACB.ult(ACC)) ||
(SPF1 == SPF_SMAX && ACB.slt(ACC))) {
Outer.replaceUsesOfWith(Inner, A);
return &Outer;
}
}
}
}
// ABS(ABS(X)) -> ABS(X)
// NABS(NABS(X)) -> NABS(X)
if (SPF1 == SPF2 && (SPF1 == SPF_ABS || SPF1 == SPF_NABS)) {
return ReplaceInstUsesWith(Outer, Inner);
}
// ABS(NABS(X)) -> ABS(X)
// NABS(ABS(X)) -> NABS(X)
if ((SPF1 == SPF_ABS && SPF2 == SPF_NABS) ||
(SPF1 == SPF_NABS && SPF2 == SPF_ABS)) {
SelectInst *SI = cast<SelectInst>(Inner);
Value *NewSI = Builder->CreateSelect(
SI->getCondition(), SI->getFalseValue(), SI->getTrueValue());
return ReplaceInstUsesWith(Outer, NewSI);
}
auto IsFreeOrProfitableToInvert =
[&](Value *V, Value *&NotV, bool &ElidesXor) {
if (match(V, m_Not(m_Value(NotV)))) {
// If V has at most 2 uses then we can get rid of the xor operation
// entirely.
ElidesXor |= !V->hasNUsesOrMore(3);
return true;
}
if (IsFreeToInvert(V, !V->hasNUsesOrMore(3))) {
NotV = nullptr;
return true;
}
return false;
};
Value *NotA, *NotB, *NotC;
bool ElidesXor = false;
// MIN(MIN(~A, ~B), ~C) == ~MAX(MAX(A, B), C)
// MIN(MAX(~A, ~B), ~C) == ~MAX(MIN(A, B), C)
// MAX(MIN(~A, ~B), ~C) == ~MIN(MAX(A, B), C)
// MAX(MAX(~A, ~B), ~C) == ~MIN(MIN(A, B), C)
//
// This transform is performance neutral if we can elide at least one xor from
// the set of three operands, since we'll be tacking on an xor at the very
// end.
if (IsFreeOrProfitableToInvert(A, NotA, ElidesXor) &&
IsFreeOrProfitableToInvert(B, NotB, ElidesXor) &&
IsFreeOrProfitableToInvert(C, NotC, ElidesXor) && ElidesXor) {
if (!NotA)
NotA = Builder->CreateNot(A);
if (!NotB)
NotB = Builder->CreateNot(B);
if (!NotC)
NotC = Builder->CreateNot(C);
Value *NewInner = generateMinMaxSelectPattern(
Builder, getInverseMinMaxSelectPattern(SPF1), NotA, NotB);
Value *NewOuter = Builder->CreateNot(generateMinMaxSelectPattern(
Builder, getInverseMinMaxSelectPattern(SPF2), NewInner, NotC));
return ReplaceInstUsesWith(Outer, NewOuter);
}
return nullptr;
}
/// foldSelectICmpAnd - If one of the constants is zero (we know they can't
/// both be) and we have an icmp instruction with zero, and we have an 'and'
/// with the non-constant value and a power of two we can turn the select
/// into a shift on the result of the 'and'.
static Value *foldSelectICmpAnd(const SelectInst &SI, ConstantInt *TrueVal,
ConstantInt *FalseVal,
InstCombiner::BuilderTy *Builder) {
const ICmpInst *IC = dyn_cast<ICmpInst>(SI.getCondition());
if (!IC || !IC->isEquality() || !SI.getType()->isIntegerTy())
return nullptr;
if (!match(IC->getOperand(1), m_Zero()))
return nullptr;
ConstantInt *AndRHS;
Value *LHS = IC->getOperand(0);
if (!match(LHS, m_And(m_Value(), m_ConstantInt(AndRHS))))
return nullptr;
// If both select arms are non-zero see if we have a select of the form
// 'x ? 2^n + C : C'. Then we can offset both arms by C, use the logic
// for 'x ? 2^n : 0' and fix the thing up at the end.
ConstantInt *Offset = nullptr;
if (!TrueVal->isZero() && !FalseVal->isZero()) {
if ((TrueVal->getValue() - FalseVal->getValue()).isPowerOf2())
Offset = FalseVal;
else if ((FalseVal->getValue() - TrueVal->getValue()).isPowerOf2())
Offset = TrueVal;
else
return nullptr;
// Adjust TrueVal and FalseVal to the offset.
TrueVal = ConstantInt::get(Builder->getContext(),
TrueVal->getValue() - Offset->getValue());
FalseVal = ConstantInt::get(Builder->getContext(),
FalseVal->getValue() - Offset->getValue());
}
// Make sure the mask in the 'and' and one of the select arms is a power of 2.
if (!AndRHS->getValue().isPowerOf2() ||
(!TrueVal->getValue().isPowerOf2() &&
!FalseVal->getValue().isPowerOf2()))
return nullptr;
// Determine which shift is needed to transform result of the 'and' into the
// desired result.
ConstantInt *ValC = !TrueVal->isZero() ? TrueVal : FalseVal;
unsigned ValZeros = ValC->getValue().logBase2();
unsigned AndZeros = AndRHS->getValue().logBase2();
// If types don't match we can still convert the select by introducing a zext
// or a trunc of the 'and'. The trunc case requires that all of the truncated
// bits are zero, we can figure that out by looking at the 'and' mask.
if (AndZeros >= ValC->getBitWidth())
return nullptr;
Value *V = Builder->CreateZExtOrTrunc(LHS, SI.getType());
if (ValZeros > AndZeros)
V = Builder->CreateShl(V, ValZeros - AndZeros);
else if (ValZeros < AndZeros)
V = Builder->CreateLShr(V, AndZeros - ValZeros);
// Okay, now we know that everything is set up, we just don't know whether we
// have a icmp_ne or icmp_eq and whether the true or false val is the zero.
bool ShouldNotVal = !TrueVal->isZero();
ShouldNotVal ^= IC->getPredicate() == ICmpInst::ICMP_NE;
if (ShouldNotVal)
V = Builder->CreateXor(V, ValC);
// Apply an offset if needed.
if (Offset)
V = Builder->CreateAdd(V, Offset);
return V;
}
Instruction *InstCombiner::visitSelectInst(SelectInst &SI) {
Value *CondVal = SI.getCondition();
Value *TrueVal = SI.getTrueValue();
Value *FalseVal = SI.getFalseValue();
if (Value *V =
SimplifySelectInst(CondVal, TrueVal, FalseVal, DL, TLI, DT, AC))
return ReplaceInstUsesWith(SI, V);
if (SI.getType()->isIntegerTy(1)) {
if (ConstantInt *C = dyn_cast<ConstantInt>(TrueVal)) {
if (C->getZExtValue()) {
// Change: A = select B, true, C --> A = or B, C
return BinaryOperator::CreateOr(CondVal, FalseVal);
}
// Change: A = select B, false, C --> A = and !B, C
Value *NotCond = Builder->CreateNot(CondVal, "not."+CondVal->getName());
return BinaryOperator::CreateAnd(NotCond, FalseVal);
}
if (ConstantInt *C = dyn_cast<ConstantInt>(FalseVal)) {
if (!C->getZExtValue()) {
// Change: A = select B, C, false --> A = and B, C
return BinaryOperator::CreateAnd(CondVal, TrueVal);
}
// Change: A = select B, C, true --> A = or !B, C
Value *NotCond = Builder->CreateNot(CondVal, "not."+CondVal->getName());
return BinaryOperator::CreateOr(NotCond, TrueVal);
}
// select a, b, a -> a&b
// select a, a, b -> a|b
if (CondVal == TrueVal)
return BinaryOperator::CreateOr(CondVal, FalseVal);
if (CondVal == FalseVal)
return BinaryOperator::CreateAnd(CondVal, TrueVal);
// select a, ~a, b -> (~a)&b
// select a, b, ~a -> (~a)|b
if (match(TrueVal, m_Not(m_Specific(CondVal))))
return BinaryOperator::CreateAnd(TrueVal, FalseVal);
if (match(FalseVal, m_Not(m_Specific(CondVal))))
return BinaryOperator::CreateOr(TrueVal, FalseVal);
}
// Selecting between two integer constants?
if (ConstantInt *TrueValC = dyn_cast<ConstantInt>(TrueVal))
if (ConstantInt *FalseValC = dyn_cast<ConstantInt>(FalseVal)) {
// select C, 1, 0 -> zext C to int
if (FalseValC->isZero() && TrueValC->getValue() == 1)
return new ZExtInst(CondVal, SI.getType());
// select C, -1, 0 -> sext C to int
if (FalseValC->isZero() && TrueValC->isAllOnesValue())
return new SExtInst(CondVal, SI.getType());
// select C, 0, 1 -> zext !C to int
if (TrueValC->isZero() && FalseValC->getValue() == 1) {
Value *NotCond = Builder->CreateNot(CondVal, "not."+CondVal->getName());
return new ZExtInst(NotCond, SI.getType());
}
// select C, 0, -1 -> sext !C to int
if (TrueValC->isZero() && FalseValC->isAllOnesValue()) {
Value *NotCond = Builder->CreateNot(CondVal, "not."+CondVal->getName());
return new SExtInst(NotCond, SI.getType());
}
if (Value *V = foldSelectICmpAnd(SI, TrueValC, FalseValC, Builder))
return ReplaceInstUsesWith(SI, V);
}
// See if we are selecting two values based on a comparison of the two values.
if (FCmpInst *FCI = dyn_cast<FCmpInst>(CondVal)) {
if (FCI->getOperand(0) == TrueVal && FCI->getOperand(1) == FalseVal) {
// Transform (X == Y) ? X : Y -> Y
if (FCI->getPredicate() == FCmpInst::FCMP_OEQ) {
// This is not safe in general for floating point:
// consider X== -0, Y== +0.
// It becomes safe if either operand is a nonzero constant.
ConstantFP *CFPt, *CFPf;
if (((CFPt = dyn_cast<ConstantFP>(TrueVal)) &&
!CFPt->getValueAPF().isZero()) ||
((CFPf = dyn_cast<ConstantFP>(FalseVal)) &&
!CFPf->getValueAPF().isZero()))
return ReplaceInstUsesWith(SI, FalseVal);
}
// Transform (X une Y) ? X : Y -> X
if (FCI->getPredicate() == FCmpInst::FCMP_UNE) {
// This is not safe in general for floating point:
// consider X== -0, Y== +0.
// It becomes safe if either operand is a nonzero constant.
ConstantFP *CFPt, *CFPf;
if (((CFPt = dyn_cast<ConstantFP>(TrueVal)) &&
!CFPt->getValueAPF().isZero()) ||
((CFPf = dyn_cast<ConstantFP>(FalseVal)) &&
!CFPf->getValueAPF().isZero()))
return ReplaceInstUsesWith(SI, TrueVal);
}
// Canonicalize to use ordered comparisons by swapping the select
// operands.
//
// e.g.
// (X ugt Y) ? X : Y -> (X ole Y) ? Y : X
if (FCI->hasOneUse() && FCmpInst::isUnordered(FCI->getPredicate())) {
FCmpInst::Predicate InvPred = FCI->getInversePredicate();
Value *NewCond = Builder->CreateFCmp(InvPred, TrueVal, FalseVal,
FCI->getName() + ".inv");
return SelectInst::Create(NewCond, FalseVal, TrueVal,
SI.getName() + ".p");
}
// NOTE: if we wanted to, this is where to detect MIN/MAX
} else if (FCI->getOperand(0) == FalseVal && FCI->getOperand(1) == TrueVal){
// Transform (X == Y) ? Y : X -> X
if (FCI->getPredicate() == FCmpInst::FCMP_OEQ) {
// This is not safe in general for floating point:
// consider X== -0, Y== +0.
// It becomes safe if either operand is a nonzero constant.
ConstantFP *CFPt, *CFPf;
if (((CFPt = dyn_cast<ConstantFP>(TrueVal)) &&
!CFPt->getValueAPF().isZero()) ||
((CFPf = dyn_cast<ConstantFP>(FalseVal)) &&
!CFPf->getValueAPF().isZero()))
return ReplaceInstUsesWith(SI, FalseVal);
}
// Transform (X une Y) ? Y : X -> Y
if (FCI->getPredicate() == FCmpInst::FCMP_UNE) {
// This is not safe in general for floating point:
// consider X== -0, Y== +0.
// It becomes safe if either operand is a nonzero constant.
ConstantFP *CFPt, *CFPf;
if (((CFPt = dyn_cast<ConstantFP>(TrueVal)) &&
!CFPt->getValueAPF().isZero()) ||
((CFPf = dyn_cast<ConstantFP>(FalseVal)) &&
!CFPf->getValueAPF().isZero()))
return ReplaceInstUsesWith(SI, TrueVal);
}
// Canonicalize to use ordered comparisons by swapping the select
// operands.
//
// e.g.
// (X ugt Y) ? X : Y -> (X ole Y) ? X : Y
if (FCI->hasOneUse() && FCmpInst::isUnordered(FCI->getPredicate())) {
FCmpInst::Predicate InvPred = FCI->getInversePredicate();
Value *NewCond = Builder->CreateFCmp(InvPred, FalseVal, TrueVal,
FCI->getName() + ".inv");
return SelectInst::Create(NewCond, FalseVal, TrueVal,
SI.getName() + ".p");
}
// NOTE: if we wanted to, this is where to detect MIN/MAX
}
// NOTE: if we wanted to, this is where to detect ABS
}
// See if we are selecting two values based on a comparison of the two values.
if (ICmpInst *ICI = dyn_cast<ICmpInst>(CondVal))
if (Instruction *Result = visitSelectInstWithICmp(SI, ICI))
return Result;
if (Instruction *TI = dyn_cast<Instruction>(TrueVal))
if (Instruction *FI = dyn_cast<Instruction>(FalseVal))
if (TI->hasOneUse() && FI->hasOneUse()) {
Instruction *AddOp = nullptr, *SubOp = nullptr;
// Turn (select C, (op X, Y), (op X, Z)) -> (op X, (select C, Y, Z))
if (TI->getOpcode() == FI->getOpcode())
if (Instruction *IV = FoldSelectOpOp(SI, TI, FI))
return IV;
// Turn select C, (X+Y), (X-Y) --> (X+(select C, Y, (-Y))). This is
// even legal for FP.
if ((TI->getOpcode() == Instruction::Sub &&
FI->getOpcode() == Instruction::Add) ||
(TI->getOpcode() == Instruction::FSub &&
FI->getOpcode() == Instruction::FAdd)) {
AddOp = FI; SubOp = TI;
} else if ((FI->getOpcode() == Instruction::Sub &&
TI->getOpcode() == Instruction::Add) ||
(FI->getOpcode() == Instruction::FSub &&
TI->getOpcode() == Instruction::FAdd)) {
AddOp = TI; SubOp = FI;
}
if (AddOp) {
Value *OtherAddOp = nullptr;
if (SubOp->getOperand(0) == AddOp->getOperand(0)) {
OtherAddOp = AddOp->getOperand(1);
} else if (SubOp->getOperand(0) == AddOp->getOperand(1)) {
OtherAddOp = AddOp->getOperand(0);
}
if (OtherAddOp) {
// So at this point we know we have (Y -> OtherAddOp):
// select C, (add X, Y), (sub X, Z)
Value *NegVal; // Compute -Z
if (SI.getType()->isFPOrFPVectorTy()) {
NegVal = Builder->CreateFNeg(SubOp->getOperand(1));
if (Instruction *NegInst = dyn_cast<Instruction>(NegVal)) {
FastMathFlags Flags = AddOp->getFastMathFlags();
Flags &= SubOp->getFastMathFlags();
NegInst->setFastMathFlags(Flags);
}
} else {
NegVal = Builder->CreateNeg(SubOp->getOperand(1));
}
Value *NewTrueOp = OtherAddOp;
Value *NewFalseOp = NegVal;
if (AddOp != TI)
std::swap(NewTrueOp, NewFalseOp);
Value *NewSel =
Builder->CreateSelect(CondVal, NewTrueOp,
NewFalseOp, SI.getName() + ".p");
if (SI.getType()->isFPOrFPVectorTy()) {
Instruction *RI =
BinaryOperator::CreateFAdd(SubOp->getOperand(0), NewSel);
FastMathFlags Flags = AddOp->getFastMathFlags();
Flags &= SubOp->getFastMathFlags();
RI->setFastMathFlags(Flags);
return RI;
} else
return BinaryOperator::CreateAdd(SubOp->getOperand(0), NewSel);
}
}
}
// See if we can fold the select into one of our operands.
if (SI.getType()->isIntOrIntVectorTy()) {
if (Instruction *FoldI = FoldSelectIntoOp(SI, TrueVal, FalseVal))
return FoldI;
Value *LHS, *RHS, *LHS2, *RHS2;
Instruction::CastOps CastOp;
SelectPatternFlavor SPF = matchSelectPattern(&SI, LHS, RHS, &CastOp);
if (SPF) {
// Canonicalize so that type casts are outside select patterns.
if (LHS->getType()->getPrimitiveSizeInBits() !=
SI.getType()->getPrimitiveSizeInBits()) {
CmpInst::Predicate Pred = getICmpPredicateForMinMax(SPF);
Value *Cmp = Builder->CreateICmp(Pred, LHS, RHS);
Value *NewSI = Builder->CreateCast(CastOp,
Builder->CreateSelect(Cmp, LHS, RHS),
SI.getType());
return ReplaceInstUsesWith(SI, NewSI);
}
// MAX(MAX(a, b), a) -> MAX(a, b)
// MIN(MIN(a, b), a) -> MIN(a, b)
// MAX(MIN(a, b), a) -> a
// MIN(MAX(a, b), a) -> a
if (SelectPatternFlavor SPF2 = matchSelectPattern(LHS, LHS2, RHS2))
if (Instruction *R = FoldSPFofSPF(cast<Instruction>(LHS),SPF2,LHS2,RHS2,
SI, SPF, RHS))
return R;
if (SelectPatternFlavor SPF2 = matchSelectPattern(RHS, LHS2, RHS2))
if (Instruction *R = FoldSPFofSPF(cast<Instruction>(RHS),SPF2,LHS2,RHS2,
SI, SPF, LHS))
return R;
}
// MAX(~a, ~b) -> ~MIN(a, b)
if (SPF == SPF_SMAX || SPF == SPF_UMAX) {
if (IsFreeToInvert(LHS, LHS->hasNUses(2)) &&
IsFreeToInvert(RHS, RHS->hasNUses(2))) {
// This transform adds a xor operation and that extra cost needs to be
// justified. We look for simplifications that will result from
// applying this rule:
bool Profitable =
(LHS->hasNUses(2) && match(LHS, m_Not(m_Value()))) ||
(RHS->hasNUses(2) && match(RHS, m_Not(m_Value()))) ||
(SI.hasOneUse() && match(*SI.user_begin(), m_Not(m_Value())));
if (Profitable) {
Value *NewLHS = Builder->CreateNot(LHS);
Value *NewRHS = Builder->CreateNot(RHS);
Value *NewCmp = SPF == SPF_SMAX
? Builder->CreateICmpSLT(NewLHS, NewRHS)
: Builder->CreateICmpULT(NewLHS, NewRHS);
Value *NewSI =
Builder->CreateNot(Builder->CreateSelect(NewCmp, NewLHS, NewRHS));
return ReplaceInstUsesWith(SI, NewSI);
}
}
}
// TODO.
// ABS(-X) -> ABS(X)
}
// See if we can fold the select into a phi node if the condition is a select.
if (isa<PHINode>(SI.getCondition()))
// The true/false values have to be live in the PHI predecessor's blocks.
if (CanSelectOperandBeMappingIntoPredBlock(TrueVal, SI) &&
CanSelectOperandBeMappingIntoPredBlock(FalseVal, SI))
if (Instruction *NV = FoldOpIntoPhi(SI))
return NV;
if (SelectInst *TrueSI = dyn_cast<SelectInst>(TrueVal)) {
if (TrueSI->getCondition()->getType() == CondVal->getType()) {
// select(C, select(C, a, b), c) -> select(C, a, c)
if (TrueSI->getCondition() == CondVal) {
if (SI.getTrueValue() == TrueSI->getTrueValue())
return nullptr;
SI.setOperand(1, TrueSI->getTrueValue());
return &SI;
}
// select(C0, select(C1, a, b), b) -> select(C0&C1, a, b)
// We choose this as normal form to enable folding on the And and shortening
// paths for the values (this helps GetUnderlyingObjects() for example).
if (TrueSI->getFalseValue() == FalseVal && TrueSI->hasOneUse()) {
Value *And = Builder->CreateAnd(CondVal, TrueSI->getCondition());
SI.setOperand(0, And);
SI.setOperand(1, TrueSI->getTrueValue());
return &SI;
}
}
}
if (SelectInst *FalseSI = dyn_cast<SelectInst>(FalseVal)) {
if (FalseSI->getCondition()->getType() == CondVal->getType()) {
// select(C, a, select(C, b, c)) -> select(C, a, c)
if (FalseSI->getCondition() == CondVal) {
if (SI.getFalseValue() == FalseSI->getFalseValue())
return nullptr;
SI.setOperand(2, FalseSI->getFalseValue());
return &SI;
}
// select(C0, a, select(C1, a, b)) -> select(C0|C1, a, b)
if (FalseSI->getTrueValue() == TrueVal && FalseSI->hasOneUse()) {
Value *Or = Builder->CreateOr(CondVal, FalseSI->getCondition());
SI.setOperand(0, Or);
SI.setOperand(2, FalseSI->getFalseValue());
return &SI;
}
}
}
if (BinaryOperator::isNot(CondVal)) {
SI.setOperand(0, BinaryOperator::getNotArgument(CondVal));
SI.setOperand(1, FalseVal);
SI.setOperand(2, TrueVal);
return &SI;
}
if (VectorType* VecTy = dyn_cast<VectorType>(SI.getType())) {
unsigned VWidth = VecTy->getNumElements();
APInt UndefElts(VWidth, 0);
APInt AllOnesEltMask(APInt::getAllOnesValue(VWidth));
if (Value *V = SimplifyDemandedVectorElts(&SI, AllOnesEltMask, UndefElts)) {
if (V != &SI)
return ReplaceInstUsesWith(SI, V);
return &SI;
}
if (isa<ConstantAggregateZero>(CondVal)) {
return ReplaceInstUsesWith(SI, FalseVal);
}
}
return nullptr;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/InstCombineVectorOps.cpp | //===- InstCombineVectorOps.cpp -------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements instcombine for ExtractElement, InsertElement and
// ShuffleVector.
//
//===----------------------------------------------------------------------===//
#include "InstCombineInternal.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/VectorUtils.h"
#include "llvm/IR/PatternMatch.h"
using namespace llvm;
using namespace PatternMatch;
#define DEBUG_TYPE "instcombine"
/// CheapToScalarize - Return true if the value is cheaper to scalarize than it
/// is to leave as a vector operation. isConstant indicates whether we're
/// extracting one known element. If false we're extracting a variable index.
static bool CheapToScalarize(Value *V, bool isConstant) {
if (Constant *C = dyn_cast<Constant>(V)) {
if (isConstant) return true;
// If all elts are the same, we can extract it and use any of the values.
if (Constant *Op0 = C->getAggregateElement(0U)) {
for (unsigned i = 1, e = V->getType()->getVectorNumElements(); i != e;
++i)
if (C->getAggregateElement(i) != Op0)
return false;
return true;
}
}
Instruction *I = dyn_cast<Instruction>(V);
if (!I) return false;
// Insert element gets simplified to the inserted element or is deleted if
// this is constant idx extract element and its a constant idx insertelt.
if (I->getOpcode() == Instruction::InsertElement && isConstant &&
isa<ConstantInt>(I->getOperand(2)))
return true;
if (I->getOpcode() == Instruction::Load && I->hasOneUse())
return true;
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(I))
if (BO->hasOneUse() &&
(CheapToScalarize(BO->getOperand(0), isConstant) ||
CheapToScalarize(BO->getOperand(1), isConstant)))
return true;
if (CmpInst *CI = dyn_cast<CmpInst>(I))
if (CI->hasOneUse() &&
(CheapToScalarize(CI->getOperand(0), isConstant) ||
CheapToScalarize(CI->getOperand(1), isConstant)))
return true;
return false;
}
// If we have a PHI node with a vector type that has only 2 uses: feed
// itself and be an operand of extractelement at a constant location,
// try to replace the PHI of the vector type with a PHI of a scalar type.
Instruction *InstCombiner::scalarizePHI(ExtractElementInst &EI, PHINode *PN) {
// Verify that the PHI node has exactly 2 uses. Otherwise return NULL.
if (!PN->hasNUses(2))
return nullptr;
// If so, it's known at this point that one operand is PHI and the other is
// an extractelement node. Find the PHI user that is not the extractelement
// node.
auto iu = PN->user_begin();
Instruction *PHIUser = dyn_cast<Instruction>(*iu);
if (PHIUser == cast<Instruction>(&EI))
PHIUser = cast<Instruction>(*(++iu));
// Verify that this PHI user has one use, which is the PHI itself,
// and that it is a binary operation which is cheap to scalarize.
// otherwise return NULL.
if (!PHIUser->hasOneUse() || !(PHIUser->user_back() == PN) ||
!(isa<BinaryOperator>(PHIUser)) || !CheapToScalarize(PHIUser, true))
return nullptr;
// Create a scalar PHI node that will replace the vector PHI node
// just before the current PHI node.
PHINode *scalarPHI = cast<PHINode>(InsertNewInstWith(
PHINode::Create(EI.getType(), PN->getNumIncomingValues(), ""), *PN));
// Scalarize each PHI operand.
for (unsigned i = 0; i < PN->getNumIncomingValues(); i++) {
Value *PHIInVal = PN->getIncomingValue(i);
BasicBlock *inBB = PN->getIncomingBlock(i);
Value *Elt = EI.getIndexOperand();
// If the operand is the PHI induction variable:
if (PHIInVal == PHIUser) {
// Scalarize the binary operation. Its first operand is the
// scalar PHI, and the second operand is extracted from the other
// vector operand.
BinaryOperator *B0 = cast<BinaryOperator>(PHIUser);
unsigned opId = (B0->getOperand(0) == PN) ? 1 : 0;
Value *Op = InsertNewInstWith(
ExtractElementInst::Create(B0->getOperand(opId), Elt,
B0->getOperand(opId)->getName() + ".Elt"),
*B0);
Value *newPHIUser = InsertNewInstWith(
BinaryOperator::Create(B0->getOpcode(), scalarPHI, Op), *B0);
scalarPHI->addIncoming(newPHIUser, inBB);
} else {
// Scalarize PHI input:
Instruction *newEI = ExtractElementInst::Create(PHIInVal, Elt, "");
// Insert the new instruction into the predecessor basic block.
Instruction *pos = dyn_cast<Instruction>(PHIInVal);
BasicBlock::iterator InsertPos;
if (pos && !isa<PHINode>(pos)) {
InsertPos = pos;
++InsertPos;
} else {
InsertPos = inBB->getFirstInsertionPt();
}
InsertNewInstWith(newEI, *InsertPos);
scalarPHI->addIncoming(newEI, inBB);
}
}
return ReplaceInstUsesWith(EI, scalarPHI);
}
Instruction *InstCombiner::visitExtractElementInst(ExtractElementInst &EI) {
if (Value *V = SimplifyExtractElementInst(
EI.getVectorOperand(), EI.getIndexOperand(), DL, TLI, DT, AC))
return ReplaceInstUsesWith(EI, V);
// If vector val is constant with all elements the same, replace EI with
// that element. We handle a known element # below.
if (Constant *C = dyn_cast<Constant>(EI.getOperand(0)))
if (CheapToScalarize(C, false))
return ReplaceInstUsesWith(EI, C->getAggregateElement(0U));
// If extracting a specified index from the vector, see if we can recursively
// find a previously computed scalar that was inserted into the vector.
if (ConstantInt *IdxC = dyn_cast<ConstantInt>(EI.getOperand(1))) {
unsigned IndexVal = IdxC->getZExtValue();
unsigned VectorWidth = EI.getVectorOperandType()->getNumElements();
// InstSimplify handles cases where the index is invalid.
assert(IndexVal < VectorWidth);
// This instruction only demands the single element from the input vector.
// If the input vector has a single use, simplify it based on this use
// property.
if (EI.getOperand(0)->hasOneUse() && VectorWidth != 1) {
APInt UndefElts(VectorWidth, 0);
APInt DemandedMask(VectorWidth, 0);
DemandedMask.setBit(IndexVal);
if (Value *V = SimplifyDemandedVectorElts(EI.getOperand(0), DemandedMask,
UndefElts)) {
EI.setOperand(0, V);
return &EI;
}
}
// If the this extractelement is directly using a bitcast from a vector of
// the same number of elements, see if we can find the source element from
// it. In this case, we will end up needing to bitcast the scalars.
if (BitCastInst *BCI = dyn_cast<BitCastInst>(EI.getOperand(0))) {
if (VectorType *VT = dyn_cast<VectorType>(BCI->getOperand(0)->getType()))
if (VT->getNumElements() == VectorWidth)
if (Value *Elt = findScalarElement(BCI->getOperand(0), IndexVal))
return new BitCastInst(Elt, EI.getType());
}
// If there's a vector PHI feeding a scalar use through this extractelement
// instruction, try to scalarize the PHI.
if (PHINode *PN = dyn_cast<PHINode>(EI.getOperand(0))) {
Instruction *scalarPHI = scalarizePHI(EI, PN);
if (scalarPHI)
return scalarPHI;
}
}
if (Instruction *I = dyn_cast<Instruction>(EI.getOperand(0))) {
// Push extractelement into predecessor operation if legal and
// profitable to do so
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(I)) {
if (I->hasOneUse() &&
CheapToScalarize(BO, isa<ConstantInt>(EI.getOperand(1)))) {
Value *newEI0 =
Builder->CreateExtractElement(BO->getOperand(0), EI.getOperand(1),
EI.getName()+".lhs");
Value *newEI1 =
Builder->CreateExtractElement(BO->getOperand(1), EI.getOperand(1),
EI.getName()+".rhs");
return BinaryOperator::Create(BO->getOpcode(), newEI0, newEI1);
}
} else if (InsertElementInst *IE = dyn_cast<InsertElementInst>(I)) {
// Extracting the inserted element?
if (IE->getOperand(2) == EI.getOperand(1))
return ReplaceInstUsesWith(EI, IE->getOperand(1));
// If the inserted and extracted elements are constants, they must not
// be the same value, extract from the pre-inserted value instead.
if (isa<Constant>(IE->getOperand(2)) && isa<Constant>(EI.getOperand(1))) {
Worklist.AddValue(EI.getOperand(0));
EI.setOperand(0, IE->getOperand(0));
return &EI;
}
} else if (ShuffleVectorInst *SVI = dyn_cast<ShuffleVectorInst>(I)) {
// If this is extracting an element from a shufflevector, figure out where
// it came from and extract from the appropriate input element instead.
if (ConstantInt *Elt = dyn_cast<ConstantInt>(EI.getOperand(1))) {
int SrcIdx = SVI->getMaskValue(Elt->getZExtValue());
Value *Src;
unsigned LHSWidth =
SVI->getOperand(0)->getType()->getVectorNumElements();
if (SrcIdx < 0)
return ReplaceInstUsesWith(EI, UndefValue::get(EI.getType()));
if (SrcIdx < (int)LHSWidth)
Src = SVI->getOperand(0);
else {
SrcIdx -= LHSWidth;
Src = SVI->getOperand(1);
}
Type *Int32Ty = Type::getInt32Ty(EI.getContext());
return ExtractElementInst::Create(Src,
ConstantInt::get(Int32Ty,
SrcIdx, false));
}
} else if (CastInst *CI = dyn_cast<CastInst>(I)) {
// Canonicalize extractelement(cast) -> cast(extractelement)
// bitcasts can change the number of vector elements and they cost nothing
if (CI->hasOneUse() && (CI->getOpcode() != Instruction::BitCast)) {
Value *EE = Builder->CreateExtractElement(CI->getOperand(0),
EI.getIndexOperand());
Worklist.AddValue(EE);
return CastInst::Create(CI->getOpcode(), EE, EI.getType());
}
} else if (SelectInst *SI = dyn_cast<SelectInst>(I)) {
if (SI->hasOneUse()) {
// TODO: For a select on vectors, it might be useful to do this if it
// has multiple extractelement uses. For vector select, that seems to
// fight the vectorizer.
// If we are extracting an element from a vector select or a select on
// vectors, a select on the scalars extracted from the vector arguments.
Value *TrueVal = SI->getTrueValue();
Value *FalseVal = SI->getFalseValue();
Value *Cond = SI->getCondition();
if (Cond->getType()->isVectorTy()) {
Cond = Builder->CreateExtractElement(Cond,
EI.getIndexOperand(),
Cond->getName() + ".elt");
}
Value *V1Elem
= Builder->CreateExtractElement(TrueVal,
EI.getIndexOperand(),
TrueVal->getName() + ".elt");
Value *V2Elem
= Builder->CreateExtractElement(FalseVal,
EI.getIndexOperand(),
FalseVal->getName() + ".elt");
return SelectInst::Create(Cond,
V1Elem,
V2Elem,
SI->getName() + ".elt");
}
}
}
return nullptr;
}
/// CollectSingleShuffleElements - If V is a shuffle of values that ONLY returns
/// elements from either LHS or RHS, return the shuffle mask and true.
/// Otherwise, return false.
static bool CollectSingleShuffleElements(Value *V, Value *LHS, Value *RHS,
SmallVectorImpl<Constant*> &Mask) {
assert(LHS->getType() == RHS->getType() &&
"Invalid CollectSingleShuffleElements");
unsigned NumElts = V->getType()->getVectorNumElements();
if (isa<UndefValue>(V)) {
Mask.assign(NumElts, UndefValue::get(Type::getInt32Ty(V->getContext())));
return true;
}
if (V == LHS) {
for (unsigned i = 0; i != NumElts; ++i)
Mask.push_back(ConstantInt::get(Type::getInt32Ty(V->getContext()), i));
return true;
}
if (V == RHS) {
for (unsigned i = 0; i != NumElts; ++i)
Mask.push_back(ConstantInt::get(Type::getInt32Ty(V->getContext()),
i+NumElts));
return true;
}
if (InsertElementInst *IEI = dyn_cast<InsertElementInst>(V)) {
// If this is an insert of an extract from some other vector, include it.
Value *VecOp = IEI->getOperand(0);
Value *ScalarOp = IEI->getOperand(1);
Value *IdxOp = IEI->getOperand(2);
if (!isa<ConstantInt>(IdxOp))
return false;
unsigned InsertedIdx = cast<ConstantInt>(IdxOp)->getZExtValue();
if (isa<UndefValue>(ScalarOp)) { // inserting undef into vector.
// We can handle this if the vector we are inserting into is
// transitively ok.
if (CollectSingleShuffleElements(VecOp, LHS, RHS, Mask)) {
// If so, update the mask to reflect the inserted undef.
Mask[InsertedIdx] = UndefValue::get(Type::getInt32Ty(V->getContext()));
return true;
}
} else if (ExtractElementInst *EI = dyn_cast<ExtractElementInst>(ScalarOp)){
if (isa<ConstantInt>(EI->getOperand(1))) {
unsigned ExtractedIdx =
cast<ConstantInt>(EI->getOperand(1))->getZExtValue();
unsigned NumLHSElts = LHS->getType()->getVectorNumElements();
// This must be extracting from either LHS or RHS.
if (EI->getOperand(0) == LHS || EI->getOperand(0) == RHS) {
// We can handle this if the vector we are inserting into is
// transitively ok.
if (CollectSingleShuffleElements(VecOp, LHS, RHS, Mask)) {
// If so, update the mask to reflect the inserted value.
if (EI->getOperand(0) == LHS) {
Mask[InsertedIdx % NumElts] =
ConstantInt::get(Type::getInt32Ty(V->getContext()),
ExtractedIdx);
} else {
assert(EI->getOperand(0) == RHS);
Mask[InsertedIdx % NumElts] =
ConstantInt::get(Type::getInt32Ty(V->getContext()),
ExtractedIdx + NumLHSElts);
}
return true;
}
}
}
}
}
return false;
}
/// We are building a shuffle to create V, which is a sequence of insertelement,
/// extractelement pairs. If PermittedRHS is set, then we must either use it or
/// not rely on the second vector source. Return a std::pair containing the
/// left and right vectors of the proposed shuffle (or 0), and set the Mask
/// parameter as required.
///
/// Note: we intentionally don't try to fold earlier shuffles since they have
/// often been chosen carefully to be efficiently implementable on the target.
typedef std::pair<Value *, Value *> ShuffleOps;
static ShuffleOps CollectShuffleElements(Value *V,
SmallVectorImpl<Constant *> &Mask,
Value *PermittedRHS) {
assert(V->getType()->isVectorTy() && "Invalid shuffle!");
unsigned NumElts = cast<VectorType>(V->getType())->getNumElements();
if (isa<UndefValue>(V)) {
Mask.assign(NumElts, UndefValue::get(Type::getInt32Ty(V->getContext())));
return std::make_pair(
PermittedRHS ? UndefValue::get(PermittedRHS->getType()) : V, nullptr);
}
if (isa<ConstantAggregateZero>(V)) {
Mask.assign(NumElts, ConstantInt::get(Type::getInt32Ty(V->getContext()),0));
return std::make_pair(V, nullptr);
}
if (InsertElementInst *IEI = dyn_cast<InsertElementInst>(V)) {
// If this is an insert of an extract from some other vector, include it.
Value *VecOp = IEI->getOperand(0);
Value *ScalarOp = IEI->getOperand(1);
Value *IdxOp = IEI->getOperand(2);
if (ExtractElementInst *EI = dyn_cast<ExtractElementInst>(ScalarOp)) {
if (isa<ConstantInt>(EI->getOperand(1)) && isa<ConstantInt>(IdxOp)) {
unsigned ExtractedIdx =
cast<ConstantInt>(EI->getOperand(1))->getZExtValue();
unsigned InsertedIdx = cast<ConstantInt>(IdxOp)->getZExtValue();
// Either the extracted from or inserted into vector must be RHSVec,
// otherwise we'd end up with a shuffle of three inputs.
if (EI->getOperand(0) == PermittedRHS || PermittedRHS == nullptr) {
Value *RHS = EI->getOperand(0);
ShuffleOps LR = CollectShuffleElements(VecOp, Mask, RHS);
assert(LR.second == nullptr || LR.second == RHS);
if (LR.first->getType() != RHS->getType()) {
// We tried our best, but we can't find anything compatible with RHS
// further up the chain. Return a trivial shuffle.
for (unsigned i = 0; i < NumElts; ++i)
Mask[i] = ConstantInt::get(Type::getInt32Ty(V->getContext()), i);
return std::make_pair(V, nullptr);
}
unsigned NumLHSElts = RHS->getType()->getVectorNumElements();
Mask[InsertedIdx % NumElts] =
ConstantInt::get(Type::getInt32Ty(V->getContext()),
NumLHSElts+ExtractedIdx);
return std::make_pair(LR.first, RHS);
}
if (VecOp == PermittedRHS) {
// We've gone as far as we can: anything on the other side of the
// extractelement will already have been converted into a shuffle.
unsigned NumLHSElts =
EI->getOperand(0)->getType()->getVectorNumElements();
for (unsigned i = 0; i != NumElts; ++i)
Mask.push_back(ConstantInt::get(
Type::getInt32Ty(V->getContext()),
i == InsertedIdx ? ExtractedIdx : NumLHSElts + i));
return std::make_pair(EI->getOperand(0), PermittedRHS);
}
// If this insertelement is a chain that comes from exactly these two
// vectors, return the vector and the effective shuffle.
if (EI->getOperand(0)->getType() == PermittedRHS->getType() &&
CollectSingleShuffleElements(IEI, EI->getOperand(0), PermittedRHS,
Mask))
return std::make_pair(EI->getOperand(0), PermittedRHS);
}
}
}
// Otherwise, can't do anything fancy. Return an identity vector.
for (unsigned i = 0; i != NumElts; ++i)
Mask.push_back(ConstantInt::get(Type::getInt32Ty(V->getContext()), i));
return std::make_pair(V, nullptr);
}
/// Try to find redundant insertvalue instructions, like the following ones:
/// %0 = insertvalue { i8, i32 } undef, i8 %x, 0
/// %1 = insertvalue { i8, i32 } %0, i8 %y, 0
/// Here the second instruction inserts values at the same indices, as the
/// first one, making the first one redundant.
/// It should be transformed to:
/// %0 = insertvalue { i8, i32 } undef, i8 %y, 0
Instruction *InstCombiner::visitInsertValueInst(InsertValueInst &I) {
bool IsRedundant = false;
ArrayRef<unsigned int> FirstIndices = I.getIndices();
// If there is a chain of insertvalue instructions (each of them except the
// last one has only one use and it's another insertvalue insn from this
// chain), check if any of the 'children' uses the same indices as the first
// instruction. In this case, the first one is redundant.
Value *V = &I;
unsigned Depth = 0;
while (V->hasOneUse() && Depth < 10) {
User *U = V->user_back();
auto UserInsInst = dyn_cast<InsertValueInst>(U);
if (!UserInsInst || U->getOperand(0) != V)
break;
if (UserInsInst->getIndices() == FirstIndices) {
IsRedundant = true;
break;
}
V = UserInsInst;
Depth++;
}
if (IsRedundant)
return ReplaceInstUsesWith(I, I.getOperand(0));
return nullptr;
}
Instruction *InstCombiner::visitInsertElementInst(InsertElementInst &IE) {
Value *VecOp = IE.getOperand(0);
Value *ScalarOp = IE.getOperand(1);
Value *IdxOp = IE.getOperand(2);
// Inserting an undef or into an undefined place, remove this.
if (isa<UndefValue>(ScalarOp) || isa<UndefValue>(IdxOp))
ReplaceInstUsesWith(IE, VecOp);
// If the inserted element was extracted from some other vector, and if the
// indexes are constant, try to turn this into a shufflevector operation.
if (ExtractElementInst *EI = dyn_cast<ExtractElementInst>(ScalarOp)) {
if (isa<ConstantInt>(EI->getOperand(1)) && isa<ConstantInt>(IdxOp)) {
unsigned NumInsertVectorElts = IE.getType()->getNumElements();
unsigned NumExtractVectorElts =
EI->getOperand(0)->getType()->getVectorNumElements();
unsigned ExtractedIdx =
cast<ConstantInt>(EI->getOperand(1))->getZExtValue();
unsigned InsertedIdx = cast<ConstantInt>(IdxOp)->getZExtValue();
if (ExtractedIdx >= NumExtractVectorElts) // Out of range extract.
return ReplaceInstUsesWith(IE, VecOp);
if (InsertedIdx >= NumInsertVectorElts) // Out of range insert.
return ReplaceInstUsesWith(IE, UndefValue::get(IE.getType()));
// If we are extracting a value from a vector, then inserting it right
// back into the same place, just use the input vector.
if (EI->getOperand(0) == VecOp && ExtractedIdx == InsertedIdx)
return ReplaceInstUsesWith(IE, VecOp);
// If this insertelement isn't used by some other insertelement, turn it
// (and any insertelements it points to), into one big shuffle.
if (!IE.hasOneUse() || !isa<InsertElementInst>(IE.user_back())) {
SmallVector<Constant*, 16> Mask;
ShuffleOps LR = CollectShuffleElements(&IE, Mask, nullptr);
// The proposed shuffle may be trivial, in which case we shouldn't
// perform the combine.
if (LR.first != &IE && LR.second != &IE) {
// We now have a shuffle of LHS, RHS, Mask.
if (LR.second == nullptr)
LR.second = UndefValue::get(LR.first->getType());
return new ShuffleVectorInst(LR.first, LR.second,
ConstantVector::get(Mask));
}
}
}
}
unsigned VWidth = cast<VectorType>(VecOp->getType())->getNumElements();
APInt UndefElts(VWidth, 0);
APInt AllOnesEltMask(APInt::getAllOnesValue(VWidth));
if (Value *V = SimplifyDemandedVectorElts(&IE, AllOnesEltMask, UndefElts)) {
if (V != &IE)
return ReplaceInstUsesWith(IE, V);
return &IE;
}
return nullptr;
}
/// Return true if we can evaluate the specified expression tree if the vector
/// elements were shuffled in a different order.
static bool CanEvaluateShuffled(Value *V, ArrayRef<int> Mask,
unsigned Depth = 5) {
// We can always reorder the elements of a constant.
if (isa<Constant>(V))
return true;
// We won't reorder vector arguments. No IPO here.
Instruction *I = dyn_cast<Instruction>(V);
if (!I) return false;
// Two users may expect different orders of the elements. Don't try it.
if (!I->hasOneUse())
return false;
if (Depth == 0) return false;
switch (I->getOpcode()) {
case Instruction::Add:
case Instruction::FAdd:
case Instruction::Sub:
case Instruction::FSub:
case Instruction::Mul:
case Instruction::FMul:
case Instruction::UDiv:
case Instruction::SDiv:
case Instruction::FDiv:
case Instruction::URem:
case Instruction::SRem:
case Instruction::FRem:
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor:
case Instruction::ICmp:
case Instruction::FCmp:
case Instruction::Trunc:
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::FPToUI:
case Instruction::FPToSI:
case Instruction::UIToFP:
case Instruction::SIToFP:
case Instruction::FPTrunc:
case Instruction::FPExt:
case Instruction::GetElementPtr: {
for (int i = 0, e = I->getNumOperands(); i != e; ++i) {
if (!CanEvaluateShuffled(I->getOperand(i), Mask, Depth-1))
return false;
}
return true;
}
case Instruction::InsertElement: {
ConstantInt *CI = dyn_cast<ConstantInt>(I->getOperand(2));
if (!CI) return false;
int ElementNumber = CI->getLimitedValue();
// Verify that 'CI' does not occur twice in Mask. A single 'insertelement'
// can't put an element into multiple indices.
bool SeenOnce = false;
for (int i = 0, e = Mask.size(); i != e; ++i) {
if (Mask[i] == ElementNumber) {
if (SeenOnce)
return false;
SeenOnce = true;
}
}
return CanEvaluateShuffled(I->getOperand(0), Mask, Depth-1);
}
}
return false;
}
/// Rebuild a new instruction just like 'I' but with the new operands given.
/// In the event of type mismatch, the type of the operands is correct.
static Value *BuildNew(Instruction *I, ArrayRef<Value*> NewOps) {
// We don't want to use the IRBuilder here because we want the replacement
// instructions to appear next to 'I', not the builder's insertion point.
switch (I->getOpcode()) {
case Instruction::Add:
case Instruction::FAdd:
case Instruction::Sub:
case Instruction::FSub:
case Instruction::Mul:
case Instruction::FMul:
case Instruction::UDiv:
case Instruction::SDiv:
case Instruction::FDiv:
case Instruction::URem:
case Instruction::SRem:
case Instruction::FRem:
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor: {
BinaryOperator *BO = cast<BinaryOperator>(I);
assert(NewOps.size() == 2 && "binary operator with #ops != 2");
BinaryOperator *New =
BinaryOperator::Create(cast<BinaryOperator>(I)->getOpcode(),
NewOps[0], NewOps[1], "", BO);
if (isa<OverflowingBinaryOperator>(BO)) {
New->setHasNoUnsignedWrap(BO->hasNoUnsignedWrap());
New->setHasNoSignedWrap(BO->hasNoSignedWrap());
}
if (isa<PossiblyExactOperator>(BO)) {
New->setIsExact(BO->isExact());
}
if (isa<FPMathOperator>(BO))
New->copyFastMathFlags(I);
return New;
}
case Instruction::ICmp:
assert(NewOps.size() == 2 && "icmp with #ops != 2");
return new ICmpInst(I, cast<ICmpInst>(I)->getPredicate(),
NewOps[0], NewOps[1]);
case Instruction::FCmp:
assert(NewOps.size() == 2 && "fcmp with #ops != 2");
return new FCmpInst(I, cast<FCmpInst>(I)->getPredicate(),
NewOps[0], NewOps[1]);
case Instruction::Trunc:
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::FPToUI:
case Instruction::FPToSI:
case Instruction::UIToFP:
case Instruction::SIToFP:
case Instruction::FPTrunc:
case Instruction::FPExt: {
// It's possible that the mask has a different number of elements from
// the original cast. We recompute the destination type to match the mask.
Type *DestTy =
VectorType::get(I->getType()->getScalarType(),
NewOps[0]->getType()->getVectorNumElements());
assert(NewOps.size() == 1 && "cast with #ops != 1");
return CastInst::Create(cast<CastInst>(I)->getOpcode(), NewOps[0], DestTy,
"", I);
}
case Instruction::GetElementPtr: {
Value *Ptr = NewOps[0];
ArrayRef<Value*> Idx = NewOps.slice(1);
GetElementPtrInst *GEP = GetElementPtrInst::Create(
cast<GetElementPtrInst>(I)->getSourceElementType(), Ptr, Idx, "", I);
GEP->setIsInBounds(cast<GetElementPtrInst>(I)->isInBounds());
return GEP;
}
}
llvm_unreachable("failed to rebuild vector instructions");
}
Value *
InstCombiner::EvaluateInDifferentElementOrder(Value *V, ArrayRef<int> Mask) {
// Mask.size() does not need to be equal to the number of vector elements.
assert(V->getType()->isVectorTy() && "can't reorder non-vector elements");
if (isa<UndefValue>(V)) {
return UndefValue::get(VectorType::get(V->getType()->getScalarType(),
Mask.size()));
}
if (isa<ConstantAggregateZero>(V)) {
return ConstantAggregateZero::get(
VectorType::get(V->getType()->getScalarType(),
Mask.size()));
}
if (Constant *C = dyn_cast<Constant>(V)) {
SmallVector<Constant *, 16> MaskValues;
for (int i = 0, e = Mask.size(); i != e; ++i) {
if (Mask[i] == -1)
MaskValues.push_back(UndefValue::get(Builder->getInt32Ty()));
else
MaskValues.push_back(Builder->getInt32(Mask[i]));
}
return ConstantExpr::getShuffleVector(C, UndefValue::get(C->getType()),
ConstantVector::get(MaskValues));
}
Instruction *I = cast<Instruction>(V);
switch (I->getOpcode()) {
case Instruction::Add:
case Instruction::FAdd:
case Instruction::Sub:
case Instruction::FSub:
case Instruction::Mul:
case Instruction::FMul:
case Instruction::UDiv:
case Instruction::SDiv:
case Instruction::FDiv:
case Instruction::URem:
case Instruction::SRem:
case Instruction::FRem:
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor:
case Instruction::ICmp:
case Instruction::FCmp:
case Instruction::Trunc:
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::FPToUI:
case Instruction::FPToSI:
case Instruction::UIToFP:
case Instruction::SIToFP:
case Instruction::FPTrunc:
case Instruction::FPExt:
case Instruction::Select:
case Instruction::GetElementPtr: {
SmallVector<Value*, 8> NewOps;
bool NeedsRebuild = (Mask.size() != I->getType()->getVectorNumElements());
for (int i = 0, e = I->getNumOperands(); i != e; ++i) {
Value *V = EvaluateInDifferentElementOrder(I->getOperand(i), Mask);
NewOps.push_back(V);
NeedsRebuild |= (V != I->getOperand(i));
}
if (NeedsRebuild) {
return BuildNew(I, NewOps);
}
return I;
}
case Instruction::InsertElement: {
int Element = cast<ConstantInt>(I->getOperand(2))->getLimitedValue();
// The insertelement was inserting at Element. Figure out which element
// that becomes after shuffling. The answer is guaranteed to be unique
// by CanEvaluateShuffled.
bool Found = false;
int Index = 0;
for (int e = Mask.size(); Index != e; ++Index) {
if (Mask[Index] == Element) {
Found = true;
break;
}
}
// If element is not in Mask, no need to handle the operand 1 (element to
// be inserted). Just evaluate values in operand 0 according to Mask.
if (!Found)
return EvaluateInDifferentElementOrder(I->getOperand(0), Mask);
Value *V = EvaluateInDifferentElementOrder(I->getOperand(0), Mask);
return InsertElementInst::Create(V, I->getOperand(1),
Builder->getInt32(Index), "", I);
}
}
llvm_unreachable("failed to reorder elements of vector instruction!");
}
static void RecognizeIdentityMask(const SmallVectorImpl<int> &Mask,
bool &isLHSID, bool &isRHSID) {
isLHSID = isRHSID = true;
for (unsigned i = 0, e = Mask.size(); i != e; ++i) {
if (Mask[i] < 0) continue; // Ignore undef values.
// Is this an identity shuffle of the LHS value?
isLHSID &= (Mask[i] == (int)i);
// Is this an identity shuffle of the RHS value?
isRHSID &= (Mask[i]-e == i);
}
}
// Returns true if the shuffle is extracting a contiguous range of values from
// LHS, for example:
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// Input: |AA|BB|CC|DD|EE|FF|GG|HH|II|JJ|KK|LL|MM|NN|OO|PP|
// Shuffles to: |EE|FF|GG|HH|
// +--+--+--+--+
static bool isShuffleExtractingFromLHS(ShuffleVectorInst &SVI,
SmallVector<int, 16> &Mask) {
unsigned LHSElems =
cast<VectorType>(SVI.getOperand(0)->getType())->getNumElements();
unsigned MaskElems = Mask.size();
unsigned BegIdx = Mask.front();
unsigned EndIdx = Mask.back();
if (BegIdx > EndIdx || EndIdx >= LHSElems || EndIdx - BegIdx != MaskElems - 1)
return false;
for (unsigned I = 0; I != MaskElems; ++I)
if (static_cast<unsigned>(Mask[I]) != BegIdx + I)
return false;
return true;
}
Instruction *InstCombiner::visitShuffleVectorInst(ShuffleVectorInst &SVI) {
Value *LHS = SVI.getOperand(0);
Value *RHS = SVI.getOperand(1);
SmallVector<int, 16> Mask = SVI.getShuffleMask();
Type *Int32Ty = Type::getInt32Ty(SVI.getContext());
bool MadeChange = false;
// Undefined shuffle mask -> undefined value.
if (isa<UndefValue>(SVI.getOperand(2)))
return ReplaceInstUsesWith(SVI, UndefValue::get(SVI.getType()));
unsigned VWidth = cast<VectorType>(SVI.getType())->getNumElements();
APInt UndefElts(VWidth, 0);
APInt AllOnesEltMask(APInt::getAllOnesValue(VWidth));
if (Value *V = SimplifyDemandedVectorElts(&SVI, AllOnesEltMask, UndefElts)) {
if (V != &SVI)
return ReplaceInstUsesWith(SVI, V);
LHS = SVI.getOperand(0);
RHS = SVI.getOperand(1);
MadeChange = true;
}
unsigned LHSWidth = cast<VectorType>(LHS->getType())->getNumElements();
// Canonicalize shuffle(x ,x,mask) -> shuffle(x, undef,mask')
// Canonicalize shuffle(undef,x,mask) -> shuffle(x, undef,mask').
if (LHS == RHS || isa<UndefValue>(LHS)) {
if (isa<UndefValue>(LHS) && LHS == RHS) {
// shuffle(undef,undef,mask) -> undef.
Value *Result = (VWidth == LHSWidth)
? LHS : UndefValue::get(SVI.getType());
return ReplaceInstUsesWith(SVI, Result);
}
// Remap any references to RHS to use LHS.
SmallVector<Constant*, 16> Elts;
for (unsigned i = 0, e = LHSWidth; i != VWidth; ++i) {
if (Mask[i] < 0) {
Elts.push_back(UndefValue::get(Int32Ty));
continue;
}
if ((Mask[i] >= (int)e && isa<UndefValue>(RHS)) ||
(Mask[i] < (int)e && isa<UndefValue>(LHS))) {
Mask[i] = -1; // Turn into undef.
Elts.push_back(UndefValue::get(Int32Ty));
} else {
Mask[i] = Mask[i] % e; // Force to LHS.
Elts.push_back(ConstantInt::get(Int32Ty, Mask[i]));
}
}
SVI.setOperand(0, SVI.getOperand(1));
SVI.setOperand(1, UndefValue::get(RHS->getType()));
SVI.setOperand(2, ConstantVector::get(Elts));
LHS = SVI.getOperand(0);
RHS = SVI.getOperand(1);
MadeChange = true;
}
if (VWidth == LHSWidth) {
// Analyze the shuffle, are the LHS or RHS and identity shuffles?
bool isLHSID, isRHSID;
RecognizeIdentityMask(Mask, isLHSID, isRHSID);
// Eliminate identity shuffles.
if (isLHSID) return ReplaceInstUsesWith(SVI, LHS);
if (isRHSID) return ReplaceInstUsesWith(SVI, RHS);
}
if (isa<UndefValue>(RHS) && CanEvaluateShuffled(LHS, Mask)) {
Value *V = EvaluateInDifferentElementOrder(LHS, Mask);
return ReplaceInstUsesWith(SVI, V);
}
// SROA generates shuffle+bitcast when the extracted sub-vector is bitcast to
// a non-vector type. We can instead bitcast the original vector followed by
// an extract of the desired element:
//
// %sroa = shufflevector <16 x i8> %in, <16 x i8> undef,
// <4 x i32> <i32 0, i32 1, i32 2, i32 3>
// %1 = bitcast <4 x i8> %sroa to i32
// Becomes:
// %bc = bitcast <16 x i8> %in to <4 x i32>
// %ext = extractelement <4 x i32> %bc, i32 0
//
// If the shuffle is extracting a contiguous range of values from the input
// vector then each use which is a bitcast of the extracted size can be
// replaced. This will work if the vector types are compatible, and the begin
// index is aligned to a value in the casted vector type. If the begin index
// isn't aligned then we can shuffle the original vector (keeping the same
// vector type) before extracting.
//
// This code will bail out if the target type is fundamentally incompatible
// with vectors of the source type.
//
// Example of <16 x i8>, target type i32:
// Index range [4,8): v-----------v Will work.
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// <16 x i8>: | | | | | | | | | | | | | | | | |
// <4 x i32>: | | | | |
// +-----------+-----------+-----------+-----------+
// Index range [6,10): ^-----------^ Needs an extra shuffle.
// Target type i40: ^--------------^ Won't work, bail.
if (isShuffleExtractingFromLHS(SVI, Mask)) {
Value *V = LHS;
unsigned MaskElems = Mask.size();
unsigned BegIdx = Mask.front();
VectorType *SrcTy = cast<VectorType>(V->getType());
unsigned VecBitWidth = SrcTy->getBitWidth();
unsigned SrcElemBitWidth = DL.getTypeSizeInBits(SrcTy->getElementType());
assert(SrcElemBitWidth && "vector elements must have a bitwidth");
unsigned SrcNumElems = SrcTy->getNumElements();
SmallVector<BitCastInst *, 8> BCs;
DenseMap<Type *, Value *> NewBCs;
for (User *U : SVI.users())
if (BitCastInst *BC = dyn_cast<BitCastInst>(U))
if (!BC->use_empty())
// Only visit bitcasts that weren't previously handled.
BCs.push_back(BC);
for (BitCastInst *BC : BCs) {
Type *TgtTy = BC->getDestTy();
unsigned TgtElemBitWidth = DL.getTypeSizeInBits(TgtTy);
if (!TgtElemBitWidth)
continue;
unsigned TgtNumElems = VecBitWidth / TgtElemBitWidth;
bool VecBitWidthsEqual = VecBitWidth == TgtNumElems * TgtElemBitWidth;
bool BegIsAligned = 0 == ((SrcElemBitWidth * BegIdx) % TgtElemBitWidth);
if (!VecBitWidthsEqual)
continue;
if (!VectorType::isValidElementType(TgtTy))
continue;
VectorType *CastSrcTy = VectorType::get(TgtTy, TgtNumElems);
if (!BegIsAligned) {
// Shuffle the input so [0,NumElements) contains the output, and
// [NumElems,SrcNumElems) is undef.
SmallVector<Constant *, 16> ShuffleMask(SrcNumElems,
UndefValue::get(Int32Ty));
for (unsigned I = 0, E = MaskElems, Idx = BegIdx; I != E; ++Idx, ++I)
ShuffleMask[I] = ConstantInt::get(Int32Ty, Idx);
V = Builder->CreateShuffleVector(V, UndefValue::get(V->getType()),
ConstantVector::get(ShuffleMask),
SVI.getName() + ".extract");
BegIdx = 0;
}
unsigned SrcElemsPerTgtElem = TgtElemBitWidth / SrcElemBitWidth;
assert(SrcElemsPerTgtElem);
BegIdx /= SrcElemsPerTgtElem;
bool BCAlreadyExists = NewBCs.find(CastSrcTy) != NewBCs.end();
auto *NewBC =
BCAlreadyExists
? NewBCs[CastSrcTy]
: Builder->CreateBitCast(V, CastSrcTy, SVI.getName() + ".bc");
if (!BCAlreadyExists)
NewBCs[CastSrcTy] = NewBC;
auto *Ext = Builder->CreateExtractElement(
NewBC, ConstantInt::get(Int32Ty, BegIdx), SVI.getName() + ".extract");
// The shufflevector isn't being replaced: the bitcast that used it
// is. InstCombine will visit the newly-created instructions.
ReplaceInstUsesWith(*BC, Ext);
MadeChange = true;
}
}
// If the LHS is a shufflevector itself, see if we can combine it with this
// one without producing an unusual shuffle.
// Cases that might be simplified:
// 1.
// x1=shuffle(v1,v2,mask1)
// x=shuffle(x1,undef,mask)
// ==>
// x=shuffle(v1,undef,newMask)
// newMask[i] = (mask[i] < x1.size()) ? mask1[mask[i]] : -1
// 2.
// x1=shuffle(v1,undef,mask1)
// x=shuffle(x1,x2,mask)
// where v1.size() == mask1.size()
// ==>
// x=shuffle(v1,x2,newMask)
// newMask[i] = (mask[i] < x1.size()) ? mask1[mask[i]] : mask[i]
// 3.
// x2=shuffle(v2,undef,mask2)
// x=shuffle(x1,x2,mask)
// where v2.size() == mask2.size()
// ==>
// x=shuffle(x1,v2,newMask)
// newMask[i] = (mask[i] < x1.size())
// ? mask[i] : mask2[mask[i]-x1.size()]+x1.size()
// 4.
// x1=shuffle(v1,undef,mask1)
// x2=shuffle(v2,undef,mask2)
// x=shuffle(x1,x2,mask)
// where v1.size() == v2.size()
// ==>
// x=shuffle(v1,v2,newMask)
// newMask[i] = (mask[i] < x1.size())
// ? mask1[mask[i]] : mask2[mask[i]-x1.size()]+v1.size()
//
// Here we are really conservative:
// we are absolutely afraid of producing a shuffle mask not in the input
// program, because the code gen may not be smart enough to turn a merged
// shuffle into two specific shuffles: it may produce worse code. As such,
// we only merge two shuffles if the result is either a splat or one of the
// input shuffle masks. In this case, merging the shuffles just removes
// one instruction, which we know is safe. This is good for things like
// turning: (splat(splat)) -> splat, or
// merge(V[0..n], V[n+1..2n]) -> V[0..2n]
ShuffleVectorInst* LHSShuffle = dyn_cast<ShuffleVectorInst>(LHS);
ShuffleVectorInst* RHSShuffle = dyn_cast<ShuffleVectorInst>(RHS);
if (LHSShuffle)
if (!isa<UndefValue>(LHSShuffle->getOperand(1)) && !isa<UndefValue>(RHS))
LHSShuffle = nullptr;
if (RHSShuffle)
if (!isa<UndefValue>(RHSShuffle->getOperand(1)))
RHSShuffle = nullptr;
if (!LHSShuffle && !RHSShuffle)
return MadeChange ? &SVI : nullptr;
Value* LHSOp0 = nullptr;
Value* LHSOp1 = nullptr;
Value* RHSOp0 = nullptr;
unsigned LHSOp0Width = 0;
unsigned RHSOp0Width = 0;
if (LHSShuffle) {
LHSOp0 = LHSShuffle->getOperand(0);
LHSOp1 = LHSShuffle->getOperand(1);
LHSOp0Width = cast<VectorType>(LHSOp0->getType())->getNumElements();
}
if (RHSShuffle) {
RHSOp0 = RHSShuffle->getOperand(0);
RHSOp0Width = cast<VectorType>(RHSOp0->getType())->getNumElements();
}
Value* newLHS = LHS;
Value* newRHS = RHS;
if (LHSShuffle) {
// case 1
if (isa<UndefValue>(RHS)) {
newLHS = LHSOp0;
newRHS = LHSOp1;
}
// case 2 or 4
else if (LHSOp0Width == LHSWidth) {
newLHS = LHSOp0;
}
}
// case 3 or 4
if (RHSShuffle && RHSOp0Width == LHSWidth) {
newRHS = RHSOp0;
}
// case 4
if (LHSOp0 == RHSOp0) {
newLHS = LHSOp0;
newRHS = nullptr;
}
if (newLHS == LHS && newRHS == RHS)
return MadeChange ? &SVI : nullptr;
SmallVector<int, 16> LHSMask;
SmallVector<int, 16> RHSMask;
if (newLHS != LHS)
LHSMask = LHSShuffle->getShuffleMask();
if (RHSShuffle && newRHS != RHS)
RHSMask = RHSShuffle->getShuffleMask();
unsigned newLHSWidth = (newLHS != LHS) ? LHSOp0Width : LHSWidth;
SmallVector<int, 16> newMask;
bool isSplat = true;
int SplatElt = -1;
// Create a new mask for the new ShuffleVectorInst so that the new
// ShuffleVectorInst is equivalent to the original one.
for (unsigned i = 0; i < VWidth; ++i) {
int eltMask;
if (Mask[i] < 0) {
// This element is an undef value.
eltMask = -1;
} else if (Mask[i] < (int)LHSWidth) {
// This element is from left hand side vector operand.
//
// If LHS is going to be replaced (case 1, 2, or 4), calculate the
// new mask value for the element.
if (newLHS != LHS) {
eltMask = LHSMask[Mask[i]];
// If the value selected is an undef value, explicitly specify it
// with a -1 mask value.
if (eltMask >= (int)LHSOp0Width && isa<UndefValue>(LHSOp1))
eltMask = -1;
} else
eltMask = Mask[i];
} else {
// This element is from right hand side vector operand
//
// If the value selected is an undef value, explicitly specify it
// with a -1 mask value. (case 1)
if (isa<UndefValue>(RHS))
eltMask = -1;
// If RHS is going to be replaced (case 3 or 4), calculate the
// new mask value for the element.
else if (newRHS != RHS) {
eltMask = RHSMask[Mask[i]-LHSWidth];
// If the value selected is an undef value, explicitly specify it
// with a -1 mask value.
if (eltMask >= (int)RHSOp0Width) {
assert(isa<UndefValue>(RHSShuffle->getOperand(1))
&& "should have been check above");
eltMask = -1;
}
} else
eltMask = Mask[i]-LHSWidth;
// If LHS's width is changed, shift the mask value accordingly.
// If newRHS == NULL, i.e. LHSOp0 == RHSOp0, we want to remap any
// references from RHSOp0 to LHSOp0, so we don't need to shift the mask.
// If newRHS == newLHS, we want to remap any references from newRHS to
// newLHS so that we can properly identify splats that may occur due to
// obfuscation across the two vectors.
if (eltMask >= 0 && newRHS != nullptr && newLHS != newRHS)
eltMask += newLHSWidth;
}
// Check if this could still be a splat.
if (eltMask >= 0) {
if (SplatElt >= 0 && SplatElt != eltMask)
isSplat = false;
SplatElt = eltMask;
}
newMask.push_back(eltMask);
}
// If the result mask is equal to one of the original shuffle masks,
// or is a splat, do the replacement.
if (isSplat || newMask == LHSMask || newMask == RHSMask || newMask == Mask) {
SmallVector<Constant*, 16> Elts;
for (unsigned i = 0, e = newMask.size(); i != e; ++i) {
if (newMask[i] < 0) {
Elts.push_back(UndefValue::get(Int32Ty));
} else {
Elts.push_back(ConstantInt::get(Int32Ty, newMask[i]));
}
}
if (!newRHS)
newRHS = UndefValue::get(newLHS->getType());
return new ShuffleVectorInst(newLHS, newRHS, ConstantVector::get(Elts));
}
// If the result mask is an identity, replace uses of this instruction with
// corresponding argument.
bool isLHSID, isRHSID;
RecognizeIdentityMask(newMask, isLHSID, isRHSID);
if (isLHSID && VWidth == LHSOp0Width) return ReplaceInstUsesWith(SVI, newLHS);
if (isRHSID && VWidth == RHSOp0Width) return ReplaceInstUsesWith(SVI, newRHS);
return MadeChange ? &SVI : nullptr;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/InstructionCombining.cpp | //===- InstructionCombining.cpp - Combine multiple instructions -----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// InstructionCombining - Combine instructions to form fewer, simple
// instructions. This pass does not modify the CFG. This pass is where
// algebraic simplification happens.
//
// This pass combines things like:
// %Y = add i32 %X, 1
// %Z = add i32 %Y, 1
// into:
// %Z = add i32 %X, 2
//
// This is a simple worklist driven algorithm.
//
// This pass guarantees that the following canonicalizations are performed on
// the program:
// 1. If a binary operator has a constant operand, it is moved to the RHS
// 2. Bitwise operators with constant operands are always grouped so that
// shifts are performed first, then or's, then and's, then xor's.
// 3. Compare instructions are converted from <,>,<=,>= to ==,!= if possible
// 4. All cmp instructions on boolean values are replaced with logical ops
// 5. add X, X is represented as (X*2) => (X << 1)
// 6. Multiplies with a power-of-two constant argument are transformed into
// shifts.
// ... etc.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/InstCombine/InstCombine.h"
#include "InstCombineInternal.h"
#include "llvm-c/Initialization.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/CFG.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/LibCallSemantics.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/Local.h"
#include <algorithm>
#include <climits>
using namespace llvm;
using namespace llvm::PatternMatch;
#define DEBUG_TYPE "instcombine"
STATISTIC(NumCombined , "Number of insts combined");
STATISTIC(NumConstProp, "Number of constant folds");
STATISTIC(NumDeadInst , "Number of dead inst eliminated");
STATISTIC(NumSunkInst , "Number of instructions sunk");
STATISTIC(NumExpand, "Number of expansions");
STATISTIC(NumFactor , "Number of factorizations");
STATISTIC(NumReassoc , "Number of reassociations");
Value *InstCombiner::EmitGEPOffset(User *GEP) {
return llvm::EmitGEPOffset(Builder, DL, GEP);
}
/// ShouldChangeType - Return true if it is desirable to convert a computation
/// from 'From' to 'To'. We don't want to convert from a legal to an illegal
/// type for example, or from a smaller to a larger illegal type.
bool InstCombiner::ShouldChangeType(Type *From, Type *To) const {
assert(From->isIntegerTy() && To->isIntegerTy());
unsigned FromWidth = From->getPrimitiveSizeInBits();
unsigned ToWidth = To->getPrimitiveSizeInBits();
bool FromLegal = DL.isLegalInteger(FromWidth);
bool ToLegal = DL.isLegalInteger(ToWidth);
// If this is a legal integer from type, and the result would be an illegal
// type, don't do the transformation.
if (FromLegal && !ToLegal)
return false;
// Otherwise, if both are illegal, do not increase the size of the result. We
// do allow things like i160 -> i64, but not i64 -> i160.
if (!FromLegal && !ToLegal && ToWidth > FromWidth)
return false;
return true;
}
// Return true, if No Signed Wrap should be maintained for I.
// The No Signed Wrap flag can be kept if the operation "B (I.getOpcode) C",
// where both B and C should be ConstantInts, results in a constant that does
// not overflow. This function only handles the Add and Sub opcodes. For
// all other opcodes, the function conservatively returns false.
static bool MaintainNoSignedWrap(BinaryOperator &I, Value *B, Value *C) {
OverflowingBinaryOperator *OBO = dyn_cast<OverflowingBinaryOperator>(&I);
if (!OBO || !OBO->hasNoSignedWrap()) {
return false;
}
// We reason about Add and Sub Only.
Instruction::BinaryOps Opcode = I.getOpcode();
if (Opcode != Instruction::Add &&
Opcode != Instruction::Sub) {
return false;
}
ConstantInt *CB = dyn_cast<ConstantInt>(B);
ConstantInt *CC = dyn_cast<ConstantInt>(C);
if (!CB || !CC) {
return false;
}
const APInt &BVal = CB->getValue();
const APInt &CVal = CC->getValue();
bool Overflow = false;
if (Opcode == Instruction::Add) {
BVal.sadd_ov(CVal, Overflow);
} else {
BVal.ssub_ov(CVal, Overflow);
}
return !Overflow;
}
/// Conservatively clears subclassOptionalData after a reassociation or
/// commutation. We preserve fast-math flags when applicable as they can be
/// preserved.
static void ClearSubclassDataAfterReassociation(BinaryOperator &I) {
FPMathOperator *FPMO = dyn_cast<FPMathOperator>(&I);
if (!FPMO) {
I.clearSubclassOptionalData();
return;
}
FastMathFlags FMF = I.getFastMathFlags();
I.clearSubclassOptionalData();
I.setFastMathFlags(FMF);
}
/// SimplifyAssociativeOrCommutative - This performs a few simplifications for
/// operators which are associative or commutative:
//
// Commutative operators:
//
// 1. Order operands such that they are listed from right (least complex) to
// left (most complex). This puts constants before unary operators before
// binary operators.
//
// Associative operators:
//
// 2. Transform: "(A op B) op C" ==> "A op (B op C)" if "B op C" simplifies.
// 3. Transform: "A op (B op C)" ==> "(A op B) op C" if "A op B" simplifies.
//
// Associative and commutative operators:
//
// 4. Transform: "(A op B) op C" ==> "(C op A) op B" if "C op A" simplifies.
// 5. Transform: "A op (B op C)" ==> "B op (C op A)" if "C op A" simplifies.
// 6. Transform: "(A op C1) op (B op C2)" ==> "(A op B) op (C1 op C2)"
// if C1 and C2 are constants.
//
bool InstCombiner::SimplifyAssociativeOrCommutative(BinaryOperator &I) {
Instruction::BinaryOps Opcode = I.getOpcode();
bool Changed = false;
do {
// Order operands such that they are listed from right (least complex) to
// left (most complex). This puts constants before unary operators before
// binary operators.
if (I.isCommutative() && getComplexity(I.getOperand(0)) <
getComplexity(I.getOperand(1)))
Changed = !I.swapOperands();
BinaryOperator *Op0 = dyn_cast<BinaryOperator>(I.getOperand(0));
BinaryOperator *Op1 = dyn_cast<BinaryOperator>(I.getOperand(1));
if (I.isAssociative()) {
// Transform: "(A op B) op C" ==> "A op (B op C)" if "B op C" simplifies.
if (Op0 && Op0->getOpcode() == Opcode) {
Value *A = Op0->getOperand(0);
Value *B = Op0->getOperand(1);
Value *C = I.getOperand(1);
// Does "B op C" simplify?
if (Value *V = SimplifyBinOp(Opcode, B, C, DL)) {
// It simplifies to V. Form "A op V".
I.setOperand(0, A);
I.setOperand(1, V);
// Conservatively clear the optional flags, since they may not be
// preserved by the reassociation.
if (MaintainNoSignedWrap(I, B, C) &&
(!Op0 || (isa<BinaryOperator>(Op0) && Op0->hasNoSignedWrap()))) {
// Note: this is only valid because SimplifyBinOp doesn't look at
// the operands to Op0.
I.clearSubclassOptionalData();
I.setHasNoSignedWrap(true);
} else {
ClearSubclassDataAfterReassociation(I);
}
Changed = true;
++NumReassoc;
continue;
}
}
// Transform: "A op (B op C)" ==> "(A op B) op C" if "A op B" simplifies.
if (Op1 && Op1->getOpcode() == Opcode) {
Value *A = I.getOperand(0);
Value *B = Op1->getOperand(0);
Value *C = Op1->getOperand(1);
// Does "A op B" simplify?
if (Value *V = SimplifyBinOp(Opcode, A, B, DL)) {
// It simplifies to V. Form "V op C".
I.setOperand(0, V);
I.setOperand(1, C);
// Conservatively clear the optional flags, since they may not be
// preserved by the reassociation.
ClearSubclassDataAfterReassociation(I);
Changed = true;
++NumReassoc;
continue;
}
}
}
if (I.isAssociative() && I.isCommutative()) {
// Transform: "(A op B) op C" ==> "(C op A) op B" if "C op A" simplifies.
if (Op0 && Op0->getOpcode() == Opcode) {
Value *A = Op0->getOperand(0);
Value *B = Op0->getOperand(1);
Value *C = I.getOperand(1);
// Does "C op A" simplify?
if (Value *V = SimplifyBinOp(Opcode, C, A, DL)) {
// It simplifies to V. Form "V op B".
I.setOperand(0, V);
I.setOperand(1, B);
// Conservatively clear the optional flags, since they may not be
// preserved by the reassociation.
ClearSubclassDataAfterReassociation(I);
Changed = true;
++NumReassoc;
continue;
}
}
// Transform: "A op (B op C)" ==> "B op (C op A)" if "C op A" simplifies.
if (Op1 && Op1->getOpcode() == Opcode) {
Value *A = I.getOperand(0);
Value *B = Op1->getOperand(0);
Value *C = Op1->getOperand(1);
// Does "C op A" simplify?
if (Value *V = SimplifyBinOp(Opcode, C, A, DL)) {
// It simplifies to V. Form "B op V".
I.setOperand(0, B);
I.setOperand(1, V);
// Conservatively clear the optional flags, since they may not be
// preserved by the reassociation.
ClearSubclassDataAfterReassociation(I);
Changed = true;
++NumReassoc;
continue;
}
}
// Transform: "(A op C1) op (B op C2)" ==> "(A op B) op (C1 op C2)"
// if C1 and C2 are constants.
if (Op0 && Op1 &&
Op0->getOpcode() == Opcode && Op1->getOpcode() == Opcode &&
isa<Constant>(Op0->getOperand(1)) &&
isa<Constant>(Op1->getOperand(1)) &&
Op0->hasOneUse() && Op1->hasOneUse()) {
Value *A = Op0->getOperand(0);
Constant *C1 = cast<Constant>(Op0->getOperand(1));
Value *B = Op1->getOperand(0);
Constant *C2 = cast<Constant>(Op1->getOperand(1));
Constant *Folded = ConstantExpr::get(Opcode, C1, C2);
BinaryOperator *New = BinaryOperator::Create(Opcode, A, B);
if (isa<FPMathOperator>(New)) {
FastMathFlags Flags = I.getFastMathFlags();
Flags &= Op0->getFastMathFlags();
Flags &= Op1->getFastMathFlags();
New->setFastMathFlags(Flags);
}
InsertNewInstWith(New, I);
New->takeName(Op1);
I.setOperand(0, New);
I.setOperand(1, Folded);
// Conservatively clear the optional flags, since they may not be
// preserved by the reassociation.
ClearSubclassDataAfterReassociation(I);
Changed = true;
continue;
}
}
// No further simplifications.
return Changed;
} while (1);
}
/// LeftDistributesOverRight - Whether "X LOp (Y ROp Z)" is always equal to
/// "(X LOp Y) ROp (X LOp Z)".
static bool LeftDistributesOverRight(Instruction::BinaryOps LOp,
Instruction::BinaryOps ROp) {
switch (LOp) {
default:
return false;
case Instruction::And:
// And distributes over Or and Xor.
switch (ROp) {
default:
return false;
case Instruction::Or:
case Instruction::Xor:
return true;
}
case Instruction::Mul:
// Multiplication distributes over addition and subtraction.
switch (ROp) {
default:
return false;
case Instruction::Add:
case Instruction::Sub:
return true;
}
case Instruction::Or:
// Or distributes over And.
switch (ROp) {
default:
return false;
case Instruction::And:
return true;
}
}
}
/// RightDistributesOverLeft - Whether "(X LOp Y) ROp Z" is always equal to
/// "(X ROp Z) LOp (Y ROp Z)".
static bool RightDistributesOverLeft(Instruction::BinaryOps LOp,
Instruction::BinaryOps ROp) {
if (Instruction::isCommutative(ROp))
return LeftDistributesOverRight(ROp, LOp);
switch (LOp) {
default:
return false;
// (X >> Z) & (Y >> Z) -> (X&Y) >> Z for all shifts.
// (X >> Z) | (Y >> Z) -> (X|Y) >> Z for all shifts.
// (X >> Z) ^ (Y >> Z) -> (X^Y) >> Z for all shifts.
case Instruction::And:
case Instruction::Or:
case Instruction::Xor:
switch (ROp) {
default:
return false;
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
return true;
}
}
// TODO: It would be nice to handle division, aka "(X + Y)/Z = X/Z + Y/Z",
// but this requires knowing that the addition does not overflow and other
// such subtleties.
return false;
}
/// This function returns identity value for given opcode, which can be used to
/// factor patterns like (X * 2) + X ==> (X * 2) + (X * 1) ==> X * (2 + 1).
static Value *getIdentityValue(Instruction::BinaryOps OpCode, Value *V) {
if (isa<Constant>(V))
return nullptr;
if (OpCode == Instruction::Mul)
return ConstantInt::get(V->getType(), 1);
// TODO: We can handle other cases e.g. Instruction::And, Instruction::Or etc.
return nullptr;
}
/// This function factors binary ops which can be combined using distributive
/// laws. This function tries to transform 'Op' based TopLevelOpcode to enable
/// factorization e.g for ADD(SHL(X , 2), MUL(X, 5)), When this function called
/// with TopLevelOpcode == Instruction::Add and Op = SHL(X, 2), transforms
/// SHL(X, 2) to MUL(X, 4) i.e. returns Instruction::Mul with LHS set to 'X' and
/// RHS to 4.
static Instruction::BinaryOps
getBinOpsForFactorization(Instruction::BinaryOps TopLevelOpcode,
BinaryOperator *Op, Value *&LHS, Value *&RHS) {
if (!Op)
return Instruction::BinaryOpsEnd;
LHS = Op->getOperand(0);
RHS = Op->getOperand(1);
switch (TopLevelOpcode) {
default:
return Op->getOpcode();
case Instruction::Add:
case Instruction::Sub:
if (Op->getOpcode() == Instruction::Shl) {
if (Constant *CST = dyn_cast<Constant>(Op->getOperand(1))) {
// The multiplier is really 1 << CST.
RHS = ConstantExpr::getShl(ConstantInt::get(Op->getType(), 1), CST);
return Instruction::Mul;
}
}
return Op->getOpcode();
}
// TODO: We can add other conversions e.g. shr => div etc.
}
/// This tries to simplify binary operations by factorizing out common terms
/// (e. g. "(A*B)+(A*C)" -> "A*(B+C)").
static Value *tryFactorization(InstCombiner::BuilderTy *Builder,
const DataLayout &DL, BinaryOperator &I,
Instruction::BinaryOps InnerOpcode, Value *A,
Value *B, Value *C, Value *D) {
// If any of A, B, C, D are null, we can not factor I, return early.
// Checking A and C should be enough.
if (!A || !C || !B || !D)
return nullptr;
Value *V = nullptr;
Value *SimplifiedInst = nullptr;
Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
Instruction::BinaryOps TopLevelOpcode = I.getOpcode();
// Does "X op' Y" always equal "Y op' X"?
bool InnerCommutative = Instruction::isCommutative(InnerOpcode);
// Does "X op' (Y op Z)" always equal "(X op' Y) op (X op' Z)"?
if (LeftDistributesOverRight(InnerOpcode, TopLevelOpcode))
// Does the instruction have the form "(A op' B) op (A op' D)" or, in the
// commutative case, "(A op' B) op (C op' A)"?
if (A == C || (InnerCommutative && A == D)) {
if (A != C)
std::swap(C, D);
// Consider forming "A op' (B op D)".
// If "B op D" simplifies then it can be formed with no cost.
V = SimplifyBinOp(TopLevelOpcode, B, D, DL);
// If "B op D" doesn't simplify then only go on if both of the existing
// operations "A op' B" and "C op' D" will be zapped as no longer used.
if (!V && LHS->hasOneUse() && RHS->hasOneUse())
V = Builder->CreateBinOp(TopLevelOpcode, B, D, RHS->getName());
if (V) {
SimplifiedInst = Builder->CreateBinOp(InnerOpcode, A, V);
}
}
// Does "(X op Y) op' Z" always equal "(X op' Z) op (Y op' Z)"?
if (!SimplifiedInst && RightDistributesOverLeft(TopLevelOpcode, InnerOpcode))
// Does the instruction have the form "(A op' B) op (C op' B)" or, in the
// commutative case, "(A op' B) op (B op' D)"?
if (B == D || (InnerCommutative && B == C)) {
if (B != D)
std::swap(C, D);
// Consider forming "(A op C) op' B".
// If "A op C" simplifies then it can be formed with no cost.
V = SimplifyBinOp(TopLevelOpcode, A, C, DL);
// If "A op C" doesn't simplify then only go on if both of the existing
// operations "A op' B" and "C op' D" will be zapped as no longer used.
if (!V && LHS->hasOneUse() && RHS->hasOneUse())
V = Builder->CreateBinOp(TopLevelOpcode, A, C, LHS->getName());
if (V) {
SimplifiedInst = Builder->CreateBinOp(InnerOpcode, V, B);
}
}
if (SimplifiedInst) {
++NumFactor;
SimplifiedInst->takeName(&I);
// Check if we can add NSW flag to SimplifiedInst. If so, set NSW flag.
// TODO: Check for NUW.
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(SimplifiedInst)) {
if (isa<OverflowingBinaryOperator>(SimplifiedInst)) {
bool HasNSW = false;
if (isa<OverflowingBinaryOperator>(&I))
HasNSW = I.hasNoSignedWrap();
if (BinaryOperator *Op0 = dyn_cast<BinaryOperator>(LHS))
if (isa<OverflowingBinaryOperator>(Op0))
HasNSW &= Op0->hasNoSignedWrap();
if (BinaryOperator *Op1 = dyn_cast<BinaryOperator>(RHS))
if (isa<OverflowingBinaryOperator>(Op1))
HasNSW &= Op1->hasNoSignedWrap();
// We can propogate 'nsw' if we know that
// %Y = mul nsw i16 %X, C
// %Z = add nsw i16 %Y, %X
// =>
// %Z = mul nsw i16 %X, C+1
//
// iff C+1 isn't INT_MIN
const APInt *CInt;
if (TopLevelOpcode == Instruction::Add &&
InnerOpcode == Instruction::Mul)
if (match(V, m_APInt(CInt)) && !CInt->isMinSignedValue())
BO->setHasNoSignedWrap(HasNSW);
}
}
}
return SimplifiedInst;
}
/// SimplifyUsingDistributiveLaws - This tries to simplify binary operations
/// which some other binary operation distributes over either by factorizing
/// out common terms (eg "(A*B)+(A*C)" -> "A*(B+C)") or expanding out if this
/// results in simplifications (eg: "A & (B | C) -> (A&B) | (A&C)" if this is
/// a win). Returns the simplified value, or null if it didn't simplify.
Value *InstCombiner::SimplifyUsingDistributiveLaws(BinaryOperator &I) {
Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
BinaryOperator *Op0 = dyn_cast<BinaryOperator>(LHS);
BinaryOperator *Op1 = dyn_cast<BinaryOperator>(RHS);
// Factorization.
Value *A = nullptr, *B = nullptr, *C = nullptr, *D = nullptr;
auto TopLevelOpcode = I.getOpcode();
auto LHSOpcode = getBinOpsForFactorization(TopLevelOpcode, Op0, A, B);
auto RHSOpcode = getBinOpsForFactorization(TopLevelOpcode, Op1, C, D);
// The instruction has the form "(A op' B) op (C op' D)". Try to factorize
// a common term.
if (LHSOpcode == RHSOpcode) {
if (Value *V = tryFactorization(Builder, DL, I, LHSOpcode, A, B, C, D))
return V;
}
// The instruction has the form "(A op' B) op (C)". Try to factorize common
// term.
if (Value *V = tryFactorization(Builder, DL, I, LHSOpcode, A, B, RHS,
getIdentityValue(LHSOpcode, RHS)))
return V;
// The instruction has the form "(B) op (C op' D)". Try to factorize common
// term.
if (Value *V = tryFactorization(Builder, DL, I, RHSOpcode, LHS,
getIdentityValue(RHSOpcode, LHS), C, D))
return V;
// Expansion.
if (Op0 && RightDistributesOverLeft(Op0->getOpcode(), TopLevelOpcode)) {
// The instruction has the form "(A op' B) op C". See if expanding it out
// to "(A op C) op' (B op C)" results in simplifications.
Value *A = Op0->getOperand(0), *B = Op0->getOperand(1), *C = RHS;
Instruction::BinaryOps InnerOpcode = Op0->getOpcode(); // op'
// Do "A op C" and "B op C" both simplify?
if (Value *L = SimplifyBinOp(TopLevelOpcode, A, C, DL))
if (Value *R = SimplifyBinOp(TopLevelOpcode, B, C, DL)) {
// They do! Return "L op' R".
++NumExpand;
// If "L op' R" equals "A op' B" then "L op' R" is just the LHS.
if ((L == A && R == B) ||
(Instruction::isCommutative(InnerOpcode) && L == B && R == A))
return Op0;
// Otherwise return "L op' R" if it simplifies.
if (Value *V = SimplifyBinOp(InnerOpcode, L, R, DL))
return V;
// Otherwise, create a new instruction.
C = Builder->CreateBinOp(InnerOpcode, L, R);
C->takeName(&I);
return C;
}
}
if (Op1 && LeftDistributesOverRight(TopLevelOpcode, Op1->getOpcode())) {
// The instruction has the form "A op (B op' C)". See if expanding it out
// to "(A op B) op' (A op C)" results in simplifications.
Value *A = LHS, *B = Op1->getOperand(0), *C = Op1->getOperand(1);
Instruction::BinaryOps InnerOpcode = Op1->getOpcode(); // op'
// Do "A op B" and "A op C" both simplify?
if (Value *L = SimplifyBinOp(TopLevelOpcode, A, B, DL))
if (Value *R = SimplifyBinOp(TopLevelOpcode, A, C, DL)) {
// They do! Return "L op' R".
++NumExpand;
// If "L op' R" equals "B op' C" then "L op' R" is just the RHS.
if ((L == B && R == C) ||
(Instruction::isCommutative(InnerOpcode) && L == C && R == B))
return Op1;
// Otherwise return "L op' R" if it simplifies.
if (Value *V = SimplifyBinOp(InnerOpcode, L, R, DL))
return V;
// Otherwise, create a new instruction.
A = Builder->CreateBinOp(InnerOpcode, L, R);
A->takeName(&I);
return A;
}
}
return nullptr;
}
// dyn_castNegVal - Given a 'sub' instruction, return the RHS of the instruction
// if the LHS is a constant zero (which is the 'negate' form).
//
Value *InstCombiner::dyn_castNegVal(Value *V) const {
if (BinaryOperator::isNeg(V))
return BinaryOperator::getNegArgument(V);
// Constants can be considered to be negated values if they can be folded.
if (ConstantInt *C = dyn_cast<ConstantInt>(V))
return ConstantExpr::getNeg(C);
if (ConstantDataVector *C = dyn_cast<ConstantDataVector>(V))
if (C->getType()->getElementType()->isIntegerTy())
return ConstantExpr::getNeg(C);
return nullptr;
}
// dyn_castFNegVal - Given a 'fsub' instruction, return the RHS of the
// instruction if the LHS is a constant negative zero (which is the 'negate'
// form).
//
Value *InstCombiner::dyn_castFNegVal(Value *V, bool IgnoreZeroSign) const {
if (BinaryOperator::isFNeg(V, IgnoreZeroSign))
return BinaryOperator::getFNegArgument(V);
// Constants can be considered to be negated values if they can be folded.
if (ConstantFP *C = dyn_cast<ConstantFP>(V))
return ConstantExpr::getFNeg(C);
if (ConstantDataVector *C = dyn_cast<ConstantDataVector>(V))
if (C->getType()->getElementType()->isFloatingPointTy())
return ConstantExpr::getFNeg(C);
return nullptr;
}
static Value *FoldOperationIntoSelectOperand(Instruction &I, Value *SO,
InstCombiner *IC) {
if (CastInst *CI = dyn_cast<CastInst>(&I)) {
return IC->Builder->CreateCast(CI->getOpcode(), SO, I.getType());
}
// Figure out if the constant is the left or the right argument.
bool ConstIsRHS = isa<Constant>(I.getOperand(1));
Constant *ConstOperand = cast<Constant>(I.getOperand(ConstIsRHS));
if (Constant *SOC = dyn_cast<Constant>(SO)) {
if (ConstIsRHS)
return ConstantExpr::get(I.getOpcode(), SOC, ConstOperand);
return ConstantExpr::get(I.getOpcode(), ConstOperand, SOC);
}
Value *Op0 = SO, *Op1 = ConstOperand;
if (!ConstIsRHS)
std::swap(Op0, Op1);
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(&I)) {
Value *RI = IC->Builder->CreateBinOp(BO->getOpcode(), Op0, Op1,
SO->getName()+".op");
Instruction *FPInst = dyn_cast<Instruction>(RI);
if (FPInst && isa<FPMathOperator>(FPInst))
FPInst->copyFastMathFlags(BO);
return RI;
}
if (ICmpInst *CI = dyn_cast<ICmpInst>(&I))
return IC->Builder->CreateICmp(CI->getPredicate(), Op0, Op1,
SO->getName()+".cmp");
if (FCmpInst *CI = dyn_cast<FCmpInst>(&I))
return IC->Builder->CreateICmp(CI->getPredicate(), Op0, Op1,
SO->getName()+".cmp");
llvm_unreachable("Unknown binary instruction type!");
}
// FoldOpIntoSelect - Given an instruction with a select as one operand and a
// constant as the other operand, try to fold the binary operator into the
// select arguments. This also works for Cast instructions, which obviously do
// not have a second operand.
Instruction *InstCombiner::FoldOpIntoSelect(Instruction &Op, SelectInst *SI) {
// Don't modify shared select instructions
if (!SI->hasOneUse()) return nullptr;
Value *TV = SI->getOperand(1);
Value *FV = SI->getOperand(2);
if (isa<Constant>(TV) || isa<Constant>(FV)) {
// Bool selects with constant operands can be folded to logical ops.
if (SI->getType()->isIntegerTy(1)) return nullptr;
// If it's a bitcast involving vectors, make sure it has the same number of
// elements on both sides.
if (BitCastInst *BC = dyn_cast<BitCastInst>(&Op)) {
VectorType *DestTy = dyn_cast<VectorType>(BC->getDestTy());
VectorType *SrcTy = dyn_cast<VectorType>(BC->getSrcTy());
// Verify that either both or neither are vectors.
if ((SrcTy == nullptr) != (DestTy == nullptr)) return nullptr;
// If vectors, verify that they have the same number of elements.
if (SrcTy && SrcTy->getNumElements() != DestTy->getNumElements())
return nullptr;
}
// Test if a CmpInst instruction is used exclusively by a select as
// part of a minimum or maximum operation. If so, refrain from doing
// any other folding. This helps out other analyses which understand
// non-obfuscated minimum and maximum idioms, such as ScalarEvolution
// and CodeGen. And in this case, at least one of the comparison
// operands has at least one user besides the compare (the select),
// which would often largely negate the benefit of folding anyway.
if (auto *CI = dyn_cast<CmpInst>(SI->getCondition())) {
if (CI->hasOneUse()) {
Value *Op0 = CI->getOperand(0), *Op1 = CI->getOperand(1);
if ((SI->getOperand(1) == Op0 && SI->getOperand(2) == Op1) ||
(SI->getOperand(2) == Op0 && SI->getOperand(1) == Op1))
return nullptr;
}
}
Value *SelectTrueVal = FoldOperationIntoSelectOperand(Op, TV, this);
Value *SelectFalseVal = FoldOperationIntoSelectOperand(Op, FV, this);
return SelectInst::Create(SI->getCondition(),
SelectTrueVal, SelectFalseVal);
}
return nullptr;
}
// HLSL change begins
static bool HasUndefValue(PHINode *PHI) {
for (unsigned i = 0; i < PHI->getNumIncomingValues(); i++)
if (isa<UndefValue>(PHI->getIncomingValue(i)))
return true;
return false;
}
// HLSL change ends
/// FoldOpIntoPhi - Given a binary operator, cast instruction, or select which
/// has a PHI node as operand #0, see if we can fold the instruction into the
/// PHI (which is only possible if all operands to the PHI are constants).
///
Instruction *InstCombiner::FoldOpIntoPhi(Instruction &I) {
PHINode *PN = cast<PHINode>(I.getOperand(0));
unsigned NumPHIValues = PN->getNumIncomingValues();
if (NumPHIValues == 0)
return nullptr;
// HLSL Change begins
// Don't fold a binary op into PHI having undef value(s).
if (HasUndefValue(PN))
return nullptr;
// HLSL Change ends
// We normally only transform phis with a single use. However, if a PHI has
// multiple uses and they are all the same operation, we can fold *all* of the
// uses into the PHI.
if (!PN->hasOneUse()) {
// Walk the use list for the instruction, comparing them to I.
for (User *U : PN->users()) {
Instruction *UI = cast<Instruction>(U);
if (UI != &I && !I.isIdenticalTo(UI))
return nullptr;
}
// Otherwise, we can replace *all* users with the new PHI we form.
}
// Check to see if all of the operands of the PHI are simple constants
// (constantint/constantfp/undef). If there is one non-constant value,
// remember the BB it is in. If there is more than one or if *it* is a PHI,
// bail out. We don't do arbitrary constant expressions here because moving
// their computation can be expensive without a cost model.
BasicBlock *NonConstBB = nullptr;
for (unsigned i = 0; i != NumPHIValues; ++i) {
Value *InVal = PN->getIncomingValue(i);
if (isa<Constant>(InVal) && !isa<ConstantExpr>(InVal))
continue;
if (isa<PHINode>(InVal)) return nullptr; // Itself a phi.
if (NonConstBB) return nullptr; // More than one non-const value.
NonConstBB = PN->getIncomingBlock(i);
// If the InVal is an invoke at the end of the pred block, then we can't
// insert a computation after it without breaking the edge.
if (InvokeInst *II = dyn_cast<InvokeInst>(InVal))
if (II->getParent() == NonConstBB)
return nullptr;
// If the incoming non-constant value is in I's block, we will remove one
// instruction, but insert another equivalent one, leading to infinite
// instcombine.
if (isPotentiallyReachable(I.getParent(), NonConstBB, DT, LI))
return nullptr;
}
// If there is exactly one non-constant value, we can insert a copy of the
// operation in that block. However, if this is a critical edge, we would be
// inserting the computation on some other paths (e.g. inside a loop). Only
// do this if the pred block is unconditionally branching into the phi block.
if (NonConstBB != nullptr) {
BranchInst *BI = dyn_cast<BranchInst>(NonConstBB->getTerminator());
if (!BI || !BI->isUnconditional()) return nullptr;
}
// Okay, we can do the transformation: create the new PHI node.
PHINode *NewPN = PHINode::Create(I.getType(), PN->getNumIncomingValues());
InsertNewInstBefore(NewPN, *PN);
NewPN->takeName(PN);
// If we are going to have to insert a new computation, do so right before the
// predecessors terminator.
if (NonConstBB)
Builder->SetInsertPoint(NonConstBB->getTerminator());
// Next, add all of the operands to the PHI.
if (SelectInst *SI = dyn_cast<SelectInst>(&I)) {
// We only currently try to fold the condition of a select when it is a phi,
// not the true/false values.
Value *TrueV = SI->getTrueValue();
Value *FalseV = SI->getFalseValue();
BasicBlock *PhiTransBB = PN->getParent();
for (unsigned i = 0; i != NumPHIValues; ++i) {
BasicBlock *ThisBB = PN->getIncomingBlock(i);
Value *TrueVInPred = TrueV->DoPHITranslation(PhiTransBB, ThisBB);
Value *FalseVInPred = FalseV->DoPHITranslation(PhiTransBB, ThisBB);
Value *InV = nullptr;
// Beware of ConstantExpr: it may eventually evaluate to getNullValue,
// even if currently isNullValue gives false.
Constant *InC = dyn_cast<Constant>(PN->getIncomingValue(i));
if (InC && !isa<ConstantExpr>(InC))
InV = InC->isNullValue() ? FalseVInPred : TrueVInPred;
else
InV = Builder->CreateSelect(PN->getIncomingValue(i),
TrueVInPred, FalseVInPred, "phitmp");
NewPN->addIncoming(InV, ThisBB);
}
} else if (CmpInst *CI = dyn_cast<CmpInst>(&I)) {
Constant *C = cast<Constant>(I.getOperand(1));
for (unsigned i = 0; i != NumPHIValues; ++i) {
Value *InV = nullptr;
if (Constant *InC = dyn_cast<Constant>(PN->getIncomingValue(i)))
InV = ConstantExpr::getCompare(CI->getPredicate(), InC, C);
else if (isa<ICmpInst>(CI))
InV = Builder->CreateICmp(CI->getPredicate(), PN->getIncomingValue(i),
C, "phitmp");
else
InV = Builder->CreateFCmp(CI->getPredicate(), PN->getIncomingValue(i),
C, "phitmp");
NewPN->addIncoming(InV, PN->getIncomingBlock(i));
}
} else if (I.getNumOperands() == 2) {
Constant *C = cast<Constant>(I.getOperand(1));
for (unsigned i = 0; i != NumPHIValues; ++i) {
Value *InV = nullptr;
if (Constant *InC = dyn_cast<Constant>(PN->getIncomingValue(i)))
InV = ConstantExpr::get(I.getOpcode(), InC, C);
else
InV = Builder->CreateBinOp(cast<BinaryOperator>(I).getOpcode(),
PN->getIncomingValue(i), C, "phitmp");
NewPN->addIncoming(InV, PN->getIncomingBlock(i));
}
} else {
CastInst *CI = cast<CastInst>(&I);
Type *RetTy = CI->getType();
for (unsigned i = 0; i != NumPHIValues; ++i) {
Value *InV;
if (Constant *InC = dyn_cast<Constant>(PN->getIncomingValue(i)))
InV = ConstantExpr::getCast(CI->getOpcode(), InC, RetTy);
else
InV = Builder->CreateCast(CI->getOpcode(),
PN->getIncomingValue(i), I.getType(), "phitmp");
NewPN->addIncoming(InV, PN->getIncomingBlock(i));
}
}
for (auto UI = PN->user_begin(), E = PN->user_end(); UI != E;) {
Instruction *User = cast<Instruction>(*UI++);
if (User == &I) continue;
ReplaceInstUsesWith(*User, NewPN);
EraseInstFromFunction(*User);
}
return ReplaceInstUsesWith(I, NewPN);
}
/// FindElementAtOffset - Given a pointer type and a constant offset, determine
/// whether or not there is a sequence of GEP indices into the pointed type that
/// will land us at the specified offset. If so, fill them into NewIndices and
/// return the resultant element type, otherwise return null.
Type *InstCombiner::FindElementAtOffset(PointerType *PtrTy, int64_t Offset,
SmallVectorImpl<Value *> &NewIndices) {
Type *Ty = PtrTy->getElementType();
if (!Ty->isSized())
return nullptr;
// Start with the index over the outer type. Note that the type size
// might be zero (even if the offset isn't zero) if the indexed type
// is something like [0 x {int, int}]
Type *IntPtrTy = DL.getIntPtrType(PtrTy);
int64_t FirstIdx = 0;
if (int64_t TySize = DL.getTypeAllocSize(Ty)) {
FirstIdx = Offset/TySize;
Offset -= FirstIdx*TySize;
// Handle hosts where % returns negative instead of values [0..TySize).
if (Offset < 0) {
--FirstIdx;
Offset += TySize;
assert(Offset >= 0);
}
assert((uint64_t)Offset < (uint64_t)TySize && "Out of range offset");
}
NewIndices.push_back(ConstantInt::get(IntPtrTy, FirstIdx));
// Index into the types. If we fail, set OrigBase to null.
while (Offset) {
// Indexing into tail padding between struct/array elements.
if (uint64_t(Offset * 8) >= DL.getTypeSizeInBits(Ty))
return nullptr;
if (StructType *STy = dyn_cast<StructType>(Ty)) {
const StructLayout *SL = DL.getStructLayout(STy);
assert(Offset < (int64_t)SL->getSizeInBytes() &&
"Offset must stay within the indexed type");
unsigned Elt = SL->getElementContainingOffset(Offset);
NewIndices.push_back(ConstantInt::get(Type::getInt32Ty(Ty->getContext()),
Elt));
Offset -= SL->getElementOffset(Elt);
Ty = STy->getElementType(Elt);
} else if (ArrayType *AT = dyn_cast<ArrayType>(Ty)) {
uint64_t EltSize = DL.getTypeAllocSize(AT->getElementType());
assert(EltSize && "Cannot index into a zero-sized array");
NewIndices.push_back(ConstantInt::get(IntPtrTy,Offset/EltSize));
Offset %= EltSize;
Ty = AT->getElementType();
} else {
// Otherwise, we can't index into the middle of this atomic type, bail.
return nullptr;
}
}
return Ty;
}
static bool shouldMergeGEPs(GEPOperator &GEP, GEPOperator &Src) {
// If this GEP has only 0 indices, it is the same pointer as
// Src. If Src is not a trivial GEP too, don't combine
// the indices.
if (GEP.hasAllZeroIndices() && !Src.hasAllZeroIndices() &&
!Src.hasOneUse())
return false;
return true;
}
/// Descale - Return a value X such that Val = X * Scale, or null if none. If
/// the multiplication is known not to overflow then NoSignedWrap is set.
Value *InstCombiner::Descale(Value *Val, APInt Scale, bool &NoSignedWrap) {
assert(isa<IntegerType>(Val->getType()) && "Can only descale integers!");
assert(cast<IntegerType>(Val->getType())->getBitWidth() ==
Scale.getBitWidth() && "Scale not compatible with value!");
// If Val is zero or Scale is one then Val = Val * Scale.
if (match(Val, m_Zero()) || Scale == 1) {
NoSignedWrap = true;
return Val;
}
// If Scale is zero then it does not divide Val.
if (Scale.isMinValue())
return nullptr;
// Look through chains of multiplications, searching for a constant that is
// divisible by Scale. For example, descaling X*(Y*(Z*4)) by a factor of 4
// will find the constant factor 4 and produce X*(Y*Z). Descaling X*(Y*8) by
// a factor of 4 will produce X*(Y*2). The principle of operation is to bore
// down from Val:
//
// Val = M1 * X || Analysis starts here and works down
// M1 = M2 * Y || Doesn't descend into terms with more
// M2 = Z * 4 \/ than one use
//
// Then to modify a term at the bottom:
//
// Val = M1 * X
// M1 = Z * Y || Replaced M2 with Z
//
// Then to work back up correcting nsw flags.
// Op - the term we are currently analyzing. Starts at Val then drills down.
// Replaced with its descaled value before exiting from the drill down loop.
Value *Op = Val;
// Parent - initially null, but after drilling down notes where Op came from.
// In the example above, Parent is (Val, 0) when Op is M1, because M1 is the
// 0'th operand of Val.
std::pair<Instruction*, unsigned> Parent;
// RequireNoSignedWrap - Set if the transform requires a descaling at deeper
// levels that doesn't overflow.
bool RequireNoSignedWrap = false;
// logScale - log base 2 of the scale. Negative if not a power of 2.
int32_t logScale = Scale.exactLogBase2();
for (;; Op = Parent.first->getOperand(Parent.second)) { // Drill down
if (ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
// If Op is a constant divisible by Scale then descale to the quotient.
APInt Quotient(Scale), Remainder(Scale); // Init ensures right bitwidth.
APInt::sdivrem(CI->getValue(), Scale, Quotient, Remainder);
if (!Remainder.isMinValue())
// Not divisible by Scale.
return nullptr;
// Replace with the quotient in the parent.
Op = ConstantInt::get(CI->getType(), Quotient);
NoSignedWrap = true;
break;
}
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(Op)) {
if (BO->getOpcode() == Instruction::Mul) {
// Multiplication.
NoSignedWrap = BO->hasNoSignedWrap();
if (RequireNoSignedWrap && !NoSignedWrap)
return nullptr;
// There are three cases for multiplication: multiplication by exactly
// the scale, multiplication by a constant different to the scale, and
// multiplication by something else.
Value *LHS = BO->getOperand(0);
Value *RHS = BO->getOperand(1);
if (ConstantInt *CI = dyn_cast<ConstantInt>(RHS)) {
// Multiplication by a constant.
if (CI->getValue() == Scale) {
// Multiplication by exactly the scale, replace the multiplication
// by its left-hand side in the parent.
Op = LHS;
break;
}
// Otherwise drill down into the constant.
if (!Op->hasOneUse())
return nullptr;
Parent = std::make_pair(BO, 1);
continue;
}
// Multiplication by something else. Drill down into the left-hand side
// since that's where the reassociate pass puts the good stuff.
if (!Op->hasOneUse())
return nullptr;
Parent = std::make_pair(BO, 0);
continue;
}
if (logScale > 0 && BO->getOpcode() == Instruction::Shl &&
isa<ConstantInt>(BO->getOperand(1))) {
// Multiplication by a power of 2.
NoSignedWrap = BO->hasNoSignedWrap();
if (RequireNoSignedWrap && !NoSignedWrap)
return nullptr;
Value *LHS = BO->getOperand(0);
int32_t Amt = cast<ConstantInt>(BO->getOperand(1))->
getLimitedValue(Scale.getBitWidth());
// Op = LHS << Amt.
if (Amt == logScale) {
// Multiplication by exactly the scale, replace the multiplication
// by its left-hand side in the parent.
Op = LHS;
break;
}
if (Amt < logScale || !Op->hasOneUse())
return nullptr;
// Multiplication by more than the scale. Reduce the multiplying amount
// by the scale in the parent.
Parent = std::make_pair(BO, 1);
Op = ConstantInt::get(BO->getType(), Amt - logScale);
break;
}
}
if (!Op->hasOneUse())
return nullptr;
if (CastInst *Cast = dyn_cast<CastInst>(Op)) {
if (Cast->getOpcode() == Instruction::SExt) {
// Op is sign-extended from a smaller type, descale in the smaller type.
unsigned SmallSize = Cast->getSrcTy()->getPrimitiveSizeInBits();
APInt SmallScale = Scale.trunc(SmallSize);
// Suppose Op = sext X, and we descale X as Y * SmallScale. We want to
// descale Op as (sext Y) * Scale. In order to have
// sext (Y * SmallScale) = (sext Y) * Scale
// some conditions need to hold however: SmallScale must sign-extend to
// Scale and the multiplication Y * SmallScale should not overflow.
if (SmallScale.sext(Scale.getBitWidth()) != Scale)
// SmallScale does not sign-extend to Scale.
return nullptr;
assert(SmallScale.exactLogBase2() == logScale);
// Require that Y * SmallScale must not overflow.
RequireNoSignedWrap = true;
// Drill down through the cast.
Parent = std::make_pair(Cast, 0);
Scale = SmallScale;
continue;
}
if (Cast->getOpcode() == Instruction::Trunc) {
// Op is truncated from a larger type, descale in the larger type.
// Suppose Op = trunc X, and we descale X as Y * sext Scale. Then
// trunc (Y * sext Scale) = (trunc Y) * Scale
// always holds. However (trunc Y) * Scale may overflow even if
// trunc (Y * sext Scale) does not, so nsw flags need to be cleared
// from this point up in the expression (see later).
if (RequireNoSignedWrap)
return nullptr;
// Drill down through the cast.
unsigned LargeSize = Cast->getSrcTy()->getPrimitiveSizeInBits();
Parent = std::make_pair(Cast, 0);
Scale = Scale.sext(LargeSize);
if (logScale + 1 == (int32_t)Cast->getType()->getPrimitiveSizeInBits())
logScale = -1;
assert(Scale.exactLogBase2() == logScale);
continue;
}
}
// Unsupported expression, bail out.
return nullptr;
}
// If Op is zero then Val = Op * Scale.
if (match(Op, m_Zero())) {
NoSignedWrap = true;
return Op;
}
// We know that we can successfully descale, so from here on we can safely
// modify the IR. Op holds the descaled version of the deepest term in the
// expression. NoSignedWrap is 'true' if multiplying Op by Scale is known
// not to overflow.
if (!Parent.first)
// The expression only had one term.
return Op;
// Rewrite the parent using the descaled version of its operand.
assert(Parent.first->hasOneUse() && "Drilled down when more than one use!");
assert(Op != Parent.first->getOperand(Parent.second) &&
"Descaling was a no-op?");
Parent.first->setOperand(Parent.second, Op);
Worklist.Add(Parent.first);
// Now work back up the expression correcting nsw flags. The logic is based
// on the following observation: if X * Y is known not to overflow as a signed
// multiplication, and Y is replaced by a value Z with smaller absolute value,
// then X * Z will not overflow as a signed multiplication either. As we work
// our way up, having NoSignedWrap 'true' means that the descaled value at the
// current level has strictly smaller absolute value than the original.
Instruction *Ancestor = Parent.first;
do {
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(Ancestor)) {
// If the multiplication wasn't nsw then we can't say anything about the
// value of the descaled multiplication, and we have to clear nsw flags
// from this point on up.
bool OpNoSignedWrap = BO->hasNoSignedWrap();
NoSignedWrap &= OpNoSignedWrap;
if (NoSignedWrap != OpNoSignedWrap) {
BO->setHasNoSignedWrap(NoSignedWrap);
Worklist.Add(Ancestor);
}
} else if (Ancestor->getOpcode() == Instruction::Trunc) {
// The fact that the descaled input to the trunc has smaller absolute
// value than the original input doesn't tell us anything useful about
// the absolute values of the truncations.
NoSignedWrap = false;
}
assert((Ancestor->getOpcode() != Instruction::SExt || NoSignedWrap) &&
"Failed to keep proper track of nsw flags while drilling down?");
if (Ancestor == Val)
// Got to the top, all done!
return Val;
// Move up one level in the expression.
assert(Ancestor->hasOneUse() && "Drilled down when more than one use!");
Ancestor = Ancestor->user_back();
} while (1);
}
/// \brief Creates node of binary operation with the same attributes as the
/// specified one but with other operands.
static Value *CreateBinOpAsGiven(BinaryOperator &Inst, Value *LHS, Value *RHS,
InstCombiner::BuilderTy *B) {
Value *BORes = B->CreateBinOp(Inst.getOpcode(), LHS, RHS);
if (BinaryOperator *NewBO = dyn_cast<BinaryOperator>(BORes)) {
if (isa<OverflowingBinaryOperator>(NewBO)) {
NewBO->setHasNoSignedWrap(Inst.hasNoSignedWrap());
NewBO->setHasNoUnsignedWrap(Inst.hasNoUnsignedWrap());
}
if (isa<PossiblyExactOperator>(NewBO))
NewBO->setIsExact(Inst.isExact());
}
return BORes;
}
/// \brief Makes transformation of binary operation specific for vector types.
/// \param Inst Binary operator to transform.
/// \return Pointer to node that must replace the original binary operator, or
/// null pointer if no transformation was made.
Value *InstCombiner::SimplifyVectorOp(BinaryOperator &Inst) {
if (!Inst.getType()->isVectorTy()) return nullptr;
// It may not be safe to reorder shuffles and things like div, urem, etc.
// because we may trap when executing those ops on unknown vector elements.
// See PR20059.
if (!isSafeToSpeculativelyExecute(&Inst))
return nullptr;
unsigned VWidth = cast<VectorType>(Inst.getType())->getNumElements();
Value *LHS = Inst.getOperand(0), *RHS = Inst.getOperand(1);
assert(cast<VectorType>(LHS->getType())->getNumElements() == VWidth);
assert(cast<VectorType>(RHS->getType())->getNumElements() == VWidth);
// If both arguments of binary operation are shuffles, which use the same
// mask and shuffle within a single vector, it is worthwhile to move the
// shuffle after binary operation:
// Op(shuffle(v1, m), shuffle(v2, m)) -> shuffle(Op(v1, v2), m)
if (isa<ShuffleVectorInst>(LHS) && isa<ShuffleVectorInst>(RHS)) {
ShuffleVectorInst *LShuf = cast<ShuffleVectorInst>(LHS);
ShuffleVectorInst *RShuf = cast<ShuffleVectorInst>(RHS);
if (isa<UndefValue>(LShuf->getOperand(1)) &&
isa<UndefValue>(RShuf->getOperand(1)) &&
LShuf->getOperand(0)->getType() == RShuf->getOperand(0)->getType() &&
LShuf->getMask() == RShuf->getMask()) {
Value *NewBO = CreateBinOpAsGiven(Inst, LShuf->getOperand(0),
RShuf->getOperand(0), Builder);
Value *Res = Builder->CreateShuffleVector(NewBO,
UndefValue::get(NewBO->getType()), LShuf->getMask());
return Res;
}
}
// If one argument is a shuffle within one vector, the other is a constant,
// try moving the shuffle after the binary operation.
ShuffleVectorInst *Shuffle = nullptr;
Constant *C1 = nullptr;
if (isa<ShuffleVectorInst>(LHS)) Shuffle = cast<ShuffleVectorInst>(LHS);
if (isa<ShuffleVectorInst>(RHS)) Shuffle = cast<ShuffleVectorInst>(RHS);
if (isa<Constant>(LHS)) C1 = cast<Constant>(LHS);
if (isa<Constant>(RHS)) C1 = cast<Constant>(RHS);
if (Shuffle && C1 &&
(isa<ConstantVector>(C1) || isa<ConstantDataVector>(C1)) &&
isa<UndefValue>(Shuffle->getOperand(1)) &&
Shuffle->getType() == Shuffle->getOperand(0)->getType()) {
SmallVector<int, 16> ShMask = Shuffle->getShuffleMask();
// Find constant C2 that has property:
// shuffle(C2, ShMask) = C1
// If such constant does not exist (example: ShMask=<0,0> and C1=<1,2>)
// reorder is not possible.
SmallVector<Constant*, 16> C2M(VWidth,
UndefValue::get(C1->getType()->getScalarType()));
bool MayChange = true;
for (unsigned I = 0; I < VWidth; ++I) {
if (ShMask[I] >= 0) {
assert(ShMask[I] < (int)VWidth);
if (!isa<UndefValue>(C2M[ShMask[I]])) {
MayChange = false;
break;
}
C2M[ShMask[I]] = C1->getAggregateElement(I);
}
}
if (MayChange) {
Constant *C2 = ConstantVector::get(C2M);
Value *NewLHS, *NewRHS;
if (isa<Constant>(LHS)) {
NewLHS = C2;
NewRHS = Shuffle->getOperand(0);
} else {
NewLHS = Shuffle->getOperand(0);
NewRHS = C2;
}
Value *NewBO = CreateBinOpAsGiven(Inst, NewLHS, NewRHS, Builder);
Value *Res = Builder->CreateShuffleVector(NewBO,
UndefValue::get(Inst.getType()), Shuffle->getMask());
return Res;
}
}
return nullptr;
}
Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
SmallVector<Value*, 8> Ops(GEP.op_begin(), GEP.op_end());
if (Value *V = SimplifyGEPInst(Ops, DL, TLI, DT, AC))
return ReplaceInstUsesWith(GEP, V);
Value *PtrOp = GEP.getOperand(0);
// Eliminate unneeded casts for indices, and replace indices which displace
// by multiples of a zero size type with zero.
bool MadeChange = false;
Type *IntPtrTy = DL.getIntPtrType(GEP.getPointerOperandType());
gep_type_iterator GTI = gep_type_begin(GEP);
for (User::op_iterator I = GEP.op_begin() + 1, E = GEP.op_end(); I != E;
++I, ++GTI) {
// Skip indices into struct types.
SequentialType *SeqTy = dyn_cast<SequentialType>(*GTI);
if (!SeqTy)
continue;
// If the element type has zero size then any index over it is equivalent
// to an index of zero, so replace it with zero if it is not zero already.
if (SeqTy->getElementType()->isSized() &&
DL.getTypeAllocSize(SeqTy->getElementType()) == 0)
if (!isa<Constant>(*I) || !cast<Constant>(*I)->isNullValue()) {
*I = Constant::getNullValue(IntPtrTy);
MadeChange = true;
}
Type *IndexTy = (*I)->getType();
if (IndexTy != IntPtrTy) {
// If we are using a wider index than needed for this platform, shrink
// it to what we need. If narrower, sign-extend it to what we need.
// This explicit cast can make subsequent optimizations more obvious.
*I = Builder->CreateIntCast(*I, IntPtrTy, true);
MadeChange = true;
}
}
if (MadeChange)
return &GEP;
// Check to see if the inputs to the PHI node are getelementptr instructions.
if (PHINode *PN = dyn_cast<PHINode>(PtrOp)) {
GetElementPtrInst *Op1 = dyn_cast<GetElementPtrInst>(PN->getOperand(0));
if (!Op1)
return nullptr;
// Don't fold a GEP into itself through a PHI node. This can only happen
// through the back-edge of a loop. Folding a GEP into itself means that
// the value of the previous iteration needs to be stored in the meantime,
// thus requiring an additional register variable to be live, but not
// actually achieving anything (the GEP still needs to be executed once per
// loop iteration).
if (Op1 == &GEP)
return nullptr;
signed DI = -1;
for (auto I = PN->op_begin()+1, E = PN->op_end(); I !=E; ++I) {
GetElementPtrInst *Op2 = dyn_cast<GetElementPtrInst>(*I);
if (!Op2 || Op1->getNumOperands() != Op2->getNumOperands())
return nullptr;
// As for Op1 above, don't try to fold a GEP into itself.
if (Op2 == &GEP)
return nullptr;
// Keep track of the type as we walk the GEP.
Type *CurTy = Op1->getOperand(0)->getType()->getScalarType();
for (unsigned J = 0, F = Op1->getNumOperands(); J != F; ++J) {
if (Op1->getOperand(J)->getType() != Op2->getOperand(J)->getType())
return nullptr;
if (Op1->getOperand(J) != Op2->getOperand(J)) {
if (DI == -1) {
// We have not seen any differences yet in the GEPs feeding the
// PHI yet, so we record this one if it is allowed to be a
// variable.
// The first two arguments can vary for any GEP, the rest have to be
// static for struct slots
if (J > 1 && CurTy->isStructTy())
return nullptr;
DI = J;
} else {
// The GEP is different by more than one input. While this could be
// extended to support GEPs that vary by more than one variable it
// doesn't make sense since it greatly increases the complexity and
// would result in an R+R+R addressing mode which no backend
// directly supports and would need to be broken into several
// simpler instructions anyway.
return nullptr;
}
}
// Sink down a layer of the type for the next iteration.
if (J > 0) {
if (CompositeType *CT = dyn_cast<CompositeType>(CurTy)) {
CurTy = CT->getTypeAtIndex(Op1->getOperand(J));
} else {
CurTy = nullptr;
}
}
}
}
GetElementPtrInst *NewGEP = cast<GetElementPtrInst>(Op1->clone());
if (DI == -1) {
// All the GEPs feeding the PHI are identical. Clone one down into our
// BB so that it can be merged with the current GEP.
GEP.getParent()->getInstList().insert(
GEP.getParent()->getFirstInsertionPt(), NewGEP);
} else {
// All the GEPs feeding the PHI differ at a single offset. Clone a GEP
// into the current block so it can be merged, and create a new PHI to
// set that index.
Instruction *InsertPt = Builder->GetInsertPoint();
Builder->SetInsertPoint(PN);
PHINode *NewPN = Builder->CreatePHI(Op1->getOperand(DI)->getType(),
PN->getNumOperands());
Builder->SetInsertPoint(InsertPt);
for (auto &I : PN->operands())
NewPN->addIncoming(cast<GEPOperator>(I)->getOperand(DI),
PN->getIncomingBlock(I));
NewGEP->setOperand(DI, NewPN);
GEP.getParent()->getInstList().insert(
GEP.getParent()->getFirstInsertionPt(), NewGEP);
NewGEP->setOperand(DI, NewPN);
}
GEP.setOperand(0, NewGEP);
PtrOp = NewGEP;
}
// Combine Indices - If the source pointer to this getelementptr instruction
// is a getelementptr instruction, combine the indices of the two
// getelementptr instructions into a single instruction.
//
if (GEPOperator *Src = dyn_cast<GEPOperator>(PtrOp)) {
if (!shouldMergeGEPs(*cast<GEPOperator>(&GEP), *Src))
return nullptr;
// Note that if our source is a gep chain itself then we wait for that
// chain to be resolved before we perform this transformation. This
// avoids us creating a TON of code in some cases.
if (GEPOperator *SrcGEP =
dyn_cast<GEPOperator>(Src->getOperand(0)))
if (SrcGEP->getNumOperands() == 2 && shouldMergeGEPs(*Src, *SrcGEP))
return nullptr; // Wait until our source is folded to completion.
SmallVector<Value*, 8> Indices;
// Find out whether the last index in the source GEP is a sequential idx.
bool EndsWithSequential = false;
for (gep_type_iterator I = gep_type_begin(*Src), E = gep_type_end(*Src);
I != E; ++I)
EndsWithSequential = !(*I)->isStructTy();
// Can we combine the two pointer arithmetics offsets?
if (EndsWithSequential) {
// Replace: gep (gep %P, long B), long A, ...
// With: T = long A+B; gep %P, T, ...
//
Value *Sum;
Value *SO1 = Src->getOperand(Src->getNumOperands()-1);
Value *GO1 = GEP.getOperand(1);
if (SO1 == Constant::getNullValue(SO1->getType())) {
Sum = GO1;
} else if (GO1 == Constant::getNullValue(GO1->getType())) {
Sum = SO1;
} else {
// If they aren't the same type, then the input hasn't been processed
// by the loop above yet (which canonicalizes sequential index types to
// intptr_t). Just avoid transforming this until the input has been
// normalized.
if (SO1->getType() != GO1->getType())
return nullptr;
// Only do the combine when GO1 and SO1 are both constants. Only in
// this case, we are sure the cost after the merge is never more than
// that before the merge.
if (!isa<Constant>(GO1) || !isa<Constant>(SO1))
return nullptr;
Sum = Builder->CreateAdd(SO1, GO1, PtrOp->getName()+".sum");
}
// Update the GEP in place if possible.
if (Src->getNumOperands() == 2) {
GEP.setOperand(0, Src->getOperand(0));
GEP.setOperand(1, Sum);
return &GEP;
}
Indices.append(Src->op_begin()+1, Src->op_end()-1);
Indices.push_back(Sum);
Indices.append(GEP.op_begin()+2, GEP.op_end());
} else if (isa<Constant>(*GEP.idx_begin()) &&
cast<Constant>(*GEP.idx_begin())->isNullValue() &&
Src->getNumOperands() != 1) {
// Otherwise we can do the fold if the first index of the GEP is a zero
Indices.append(Src->op_begin()+1, Src->op_end());
Indices.append(GEP.idx_begin()+1, GEP.idx_end());
}
if (!Indices.empty())
return GEP.isInBounds() && Src->isInBounds()
? GetElementPtrInst::CreateInBounds(
Src->getSourceElementType(), Src->getOperand(0), Indices,
GEP.getName())
: GetElementPtrInst::Create(Src->getSourceElementType(),
Src->getOperand(0), Indices,
GEP.getName());
}
if (GEP.getNumIndices() == 1) {
unsigned AS = GEP.getPointerAddressSpace();
if (GEP.getOperand(1)->getType()->getScalarSizeInBits() ==
DL.getPointerSizeInBits(AS)) {
Type *PtrTy = GEP.getPointerOperandType();
Type *Ty = PtrTy->getPointerElementType();
uint64_t TyAllocSize = DL.getTypeAllocSize(Ty);
bool Matched = false;
uint64_t C;
Value *V = nullptr;
if (TyAllocSize == 1) {
V = GEP.getOperand(1);
Matched = true;
} else if (match(GEP.getOperand(1),
m_AShr(m_Value(V), m_ConstantInt(C)))) {
if (TyAllocSize == 1ULL << C)
Matched = true;
} else if (match(GEP.getOperand(1),
m_SDiv(m_Value(V), m_ConstantInt(C)))) {
if (TyAllocSize == C)
Matched = true;
}
if (Matched) {
// Canonicalize (gep i8* X, -(ptrtoint Y))
// to (inttoptr (sub (ptrtoint X), (ptrtoint Y)))
// The GEP pattern is emitted by the SCEV expander for certain kinds of
// pointer arithmetic.
if (match(V, m_Neg(m_PtrToInt(m_Value())))) {
Operator *Index = cast<Operator>(V);
Value *PtrToInt = Builder->CreatePtrToInt(PtrOp, Index->getType());
Value *NewSub = Builder->CreateSub(PtrToInt, Index->getOperand(1));
return CastInst::Create(Instruction::IntToPtr, NewSub, GEP.getType());
}
// Canonicalize (gep i8* X, (ptrtoint Y)-(ptrtoint X))
// to (bitcast Y)
Value *Y;
if (match(V, m_Sub(m_PtrToInt(m_Value(Y)),
m_PtrToInt(m_Specific(GEP.getOperand(0)))))) {
return CastInst::CreatePointerBitCastOrAddrSpaceCast(Y,
GEP.getType());
}
}
}
}
// Handle gep(bitcast x) and gep(gep x, 0, 0, 0).
Value *StrippedPtr = PtrOp->stripPointerCasts();
PointerType *StrippedPtrTy = dyn_cast<PointerType>(StrippedPtr->getType());
// We do not handle pointer-vector geps here.
if (!StrippedPtrTy)
return nullptr;
if (StrippedPtr != PtrOp) {
bool HasZeroPointerIndex = false;
if (ConstantInt *C = dyn_cast<ConstantInt>(GEP.getOperand(1)))
HasZeroPointerIndex = C->isZero();
// Transform: GEP (bitcast [10 x i8]* X to [0 x i8]*), i32 0, ...
// into : GEP [10 x i8]* X, i32 0, ...
//
// Likewise, transform: GEP (bitcast i8* X to [0 x i8]*), i32 0, ...
// into : GEP i8* X, ...
//
// This occurs when the program declares an array extern like "int X[];"
if (HasZeroPointerIndex) {
PointerType *CPTy = cast<PointerType>(PtrOp->getType());
if (ArrayType *CATy =
dyn_cast<ArrayType>(CPTy->getElementType())) {
// GEP (bitcast i8* X to [0 x i8]*), i32 0, ... ?
if (CATy->getElementType() == StrippedPtrTy->getElementType()) {
// -> GEP i8* X, ...
SmallVector<Value*, 8> Idx(GEP.idx_begin()+1, GEP.idx_end());
GetElementPtrInst *Res = GetElementPtrInst::Create(
StrippedPtrTy->getElementType(), StrippedPtr, Idx, GEP.getName());
Res->setIsInBounds(GEP.isInBounds());
if (StrippedPtrTy->getAddressSpace() == GEP.getAddressSpace())
return Res;
// Insert Res, and create an addrspacecast.
// e.g.,
// GEP (addrspacecast i8 addrspace(1)* X to [0 x i8]*), i32 0, ...
// ->
// %0 = GEP i8 addrspace(1)* X, ...
// addrspacecast i8 addrspace(1)* %0 to i8*
return new AddrSpaceCastInst(Builder->Insert(Res), GEP.getType());
}
if (ArrayType *XATy =
dyn_cast<ArrayType>(StrippedPtrTy->getElementType())){
// GEP (bitcast [10 x i8]* X to [0 x i8]*), i32 0, ... ?
if (CATy->getElementType() == XATy->getElementType()) {
// -> GEP [10 x i8]* X, i32 0, ...
// At this point, we know that the cast source type is a pointer
// to an array of the same type as the destination pointer
// array. Because the array type is never stepped over (there
// is a leading zero) we can fold the cast into this GEP.
if (StrippedPtrTy->getAddressSpace() == GEP.getAddressSpace()) {
GEP.setOperand(0, StrippedPtr);
GEP.setSourceElementType(XATy);
return &GEP;
}
// Cannot replace the base pointer directly because StrippedPtr's
// address space is different. Instead, create a new GEP followed by
// an addrspacecast.
// e.g.,
// GEP (addrspacecast [10 x i8] addrspace(1)* X to [0 x i8]*),
// i32 0, ...
// ->
// %0 = GEP [10 x i8] addrspace(1)* X, ...
// addrspacecast i8 addrspace(1)* %0 to i8*
SmallVector<Value*, 8> Idx(GEP.idx_begin(), GEP.idx_end());
Value *NewGEP = GEP.isInBounds()
? Builder->CreateInBoundsGEP(
nullptr, StrippedPtr, Idx, GEP.getName())
: Builder->CreateGEP(nullptr, StrippedPtr, Idx,
GEP.getName());
return new AddrSpaceCastInst(NewGEP, GEP.getType());
}
}
}
} else if (GEP.getNumOperands() == 2) {
// Transform things like:
// %t = getelementptr i32* bitcast ([2 x i32]* %str to i32*), i32 %V
// into: %t1 = getelementptr [2 x i32]* %str, i32 0, i32 %V; bitcast
Type *SrcElTy = StrippedPtrTy->getElementType();
Type *ResElTy = PtrOp->getType()->getPointerElementType();
if (SrcElTy->isArrayTy() &&
DL.getTypeAllocSize(SrcElTy->getArrayElementType()) ==
DL.getTypeAllocSize(ResElTy)) {
Type *IdxType = DL.getIntPtrType(GEP.getType());
Value *Idx[2] = { Constant::getNullValue(IdxType), GEP.getOperand(1) };
Value *NewGEP =
GEP.isInBounds()
? Builder->CreateInBoundsGEP(nullptr, StrippedPtr, Idx,
GEP.getName())
: Builder->CreateGEP(nullptr, StrippedPtr, Idx, GEP.getName());
// V and GEP are both pointer types --> BitCast
return CastInst::CreatePointerBitCastOrAddrSpaceCast(NewGEP,
GEP.getType());
}
// Transform things like:
// %V = mul i64 %N, 4
// %t = getelementptr i8* bitcast (i32* %arr to i8*), i32 %V
// into: %t1 = getelementptr i32* %arr, i32 %N; bitcast
if (ResElTy->isSized() && SrcElTy->isSized()) {
// Check that changing the type amounts to dividing the index by a scale
// factor.
uint64_t ResSize = DL.getTypeAllocSize(ResElTy);
uint64_t SrcSize = DL.getTypeAllocSize(SrcElTy);
if (ResSize && SrcSize % ResSize == 0) {
Value *Idx = GEP.getOperand(1);
unsigned BitWidth = Idx->getType()->getPrimitiveSizeInBits();
uint64_t Scale = SrcSize / ResSize;
// Earlier transforms ensure that the index has type IntPtrType, which
// considerably simplifies the logic by eliminating implicit casts.
assert(Idx->getType() == DL.getIntPtrType(GEP.getType()) &&
"Index not cast to pointer width?");
bool NSW;
if (Value *NewIdx = Descale(Idx, APInt(BitWidth, Scale), NSW)) {
// Successfully decomposed Idx as NewIdx * Scale, form a new GEP.
// If the multiplication NewIdx * Scale may overflow then the new
// GEP may not be "inbounds".
Value *NewGEP =
GEP.isInBounds() && NSW
? Builder->CreateInBoundsGEP(nullptr, StrippedPtr, NewIdx,
GEP.getName())
: Builder->CreateGEP(nullptr, StrippedPtr, NewIdx,
GEP.getName());
// The NewGEP must be pointer typed, so must the old one -> BitCast
return CastInst::CreatePointerBitCastOrAddrSpaceCast(NewGEP,
GEP.getType());
}
}
}
// Similarly, transform things like:
// getelementptr i8* bitcast ([100 x double]* X to i8*), i32 %tmp
// (where tmp = 8*tmp2) into:
// getelementptr [100 x double]* %arr, i32 0, i32 %tmp2; bitcast
if (ResElTy->isSized() && SrcElTy->isSized() && SrcElTy->isArrayTy()) {
// Check that changing to the array element type amounts to dividing the
// index by a scale factor.
uint64_t ResSize = DL.getTypeAllocSize(ResElTy);
uint64_t ArrayEltSize =
DL.getTypeAllocSize(SrcElTy->getArrayElementType());
if (ResSize && ArrayEltSize % ResSize == 0) {
Value *Idx = GEP.getOperand(1);
unsigned BitWidth = Idx->getType()->getPrimitiveSizeInBits();
uint64_t Scale = ArrayEltSize / ResSize;
// Earlier transforms ensure that the index has type IntPtrType, which
// considerably simplifies the logic by eliminating implicit casts.
assert(Idx->getType() == DL.getIntPtrType(GEP.getType()) &&
"Index not cast to pointer width?");
bool NSW;
if (Value *NewIdx = Descale(Idx, APInt(BitWidth, Scale), NSW)) {
// Successfully decomposed Idx as NewIdx * Scale, form a new GEP.
// If the multiplication NewIdx * Scale may overflow then the new
// GEP may not be "inbounds".
Value *Off[2] = {
Constant::getNullValue(DL.getIntPtrType(GEP.getType())),
NewIdx};
Value *NewGEP = GEP.isInBounds() && NSW
? Builder->CreateInBoundsGEP(
SrcElTy, StrippedPtr, Off, GEP.getName())
: Builder->CreateGEP(SrcElTy, StrippedPtr, Off,
GEP.getName());
// The NewGEP must be pointer typed, so must the old one -> BitCast
return CastInst::CreatePointerBitCastOrAddrSpaceCast(NewGEP,
GEP.getType());
}
}
}
}
}
// addrspacecast between types is canonicalized as a bitcast, then an
// addrspacecast. To take advantage of the below bitcast + struct GEP, look
// through the addrspacecast.
if (AddrSpaceCastInst *ASC = dyn_cast<AddrSpaceCastInst>(PtrOp)) {
// X = bitcast A addrspace(1)* to B addrspace(1)*
// Y = addrspacecast A addrspace(1)* to B addrspace(2)*
// Z = gep Y, <...constant indices...>
// Into an addrspacecasted GEP of the struct.
if (BitCastInst *BC = dyn_cast<BitCastInst>(ASC->getOperand(0)))
PtrOp = BC;
}
/// See if we can simplify:
/// X = bitcast A* to B*
/// Y = gep X, <...constant indices...>
/// into a gep of the original struct. This is important for SROA and alias
/// analysis of unions. If "A" is also a bitcast, wait for A/X to be merged.
if (BitCastInst *BCI = dyn_cast<BitCastInst>(PtrOp)) {
Value *Operand = BCI->getOperand(0);
PointerType *OpType = cast<PointerType>(Operand->getType());
unsigned OffsetBits = DL.getPointerTypeSizeInBits(GEP.getType());
APInt Offset(OffsetBits, 0);
if (!isa<BitCastInst>(Operand) &&
GEP.accumulateConstantOffset(DL, Offset)) {
// If this GEP instruction doesn't move the pointer, just replace the GEP
// with a bitcast of the real input to the dest type.
if (!Offset) {
// If the bitcast is of an allocation, and the allocation will be
// converted to match the type of the cast, don't touch this.
if (isa<AllocaInst>(Operand) || isAllocationFn(Operand, TLI)) {
// See if the bitcast simplifies, if so, don't nuke this GEP yet.
if (Instruction *I = visitBitCast(*BCI)) {
if (I != BCI) {
I->takeName(BCI);
BCI->getParent()->getInstList().insert(BCI, I);
ReplaceInstUsesWith(*BCI, I);
}
return &GEP;
}
}
if (Operand->getType()->getPointerAddressSpace() != GEP.getAddressSpace())
return new AddrSpaceCastInst(Operand, GEP.getType());
return new BitCastInst(Operand, GEP.getType());
}
// Otherwise, if the offset is non-zero, we need to find out if there is a
// field at Offset in 'A's type. If so, we can pull the cast through the
// GEP.
SmallVector<Value*, 8> NewIndices;
if (FindElementAtOffset(OpType, Offset.getSExtValue(), NewIndices)) {
Value *NGEP =
GEP.isInBounds()
? Builder->CreateInBoundsGEP(nullptr, Operand, NewIndices)
: Builder->CreateGEP(nullptr, Operand, NewIndices);
if (NGEP->getType() == GEP.getType())
return ReplaceInstUsesWith(GEP, NGEP);
NGEP->takeName(&GEP);
if (NGEP->getType()->getPointerAddressSpace() != GEP.getAddressSpace())
return new AddrSpaceCastInst(NGEP, GEP.getType());
return new BitCastInst(NGEP, GEP.getType());
}
}
}
return nullptr;
}
static bool isAllocSiteRemovable(Instruction *AI,
SmallVectorImpl<WeakTrackingVH> &Users,
const TargetLibraryInfo *TLI) {
SmallVector<Instruction*, 4> Worklist;
Worklist.push_back(AI);
do {
Instruction *PI = Worklist.pop_back_val();
for (User *U : PI->users()) {
Instruction *I = cast<Instruction>(U);
switch (I->getOpcode()) {
default:
// Give up the moment we see something we can't handle.
return false;
case Instruction::BitCast:
case Instruction::GetElementPtr:
Users.emplace_back(I);
Worklist.push_back(I);
continue;
case Instruction::ICmp: {
ICmpInst *ICI = cast<ICmpInst>(I);
// We can fold eq/ne comparisons with null to false/true, respectively.
if (!ICI->isEquality() || !isa<ConstantPointerNull>(ICI->getOperand(1)))
return false;
Users.emplace_back(I);
continue;
}
case Instruction::Call:
// Ignore no-op and store intrinsics.
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I)) {
switch (II->getIntrinsicID()) {
default:
return false;
case Intrinsic::memmove:
case Intrinsic::memcpy:
case Intrinsic::memset: {
MemIntrinsic *MI = cast<MemIntrinsic>(II);
if (MI->isVolatile() || MI->getRawDest() != PI)
return false;
}
LLVM_FALLTHROUGH; // HLSL Change
case Intrinsic::dbg_declare:
case Intrinsic::dbg_value:
case Intrinsic::invariant_start:
case Intrinsic::invariant_end:
case Intrinsic::lifetime_start:
case Intrinsic::lifetime_end:
case Intrinsic::objectsize:
Users.emplace_back(I);
continue;
}
}
if (isFreeCall(I, TLI)) {
Users.emplace_back(I);
continue;
}
return false;
case Instruction::Store: {
StoreInst *SI = cast<StoreInst>(I);
if (SI->isVolatile() || SI->getPointerOperand() != PI)
return false;
Users.emplace_back(I);
continue;
}
}
llvm_unreachable("missing a return?");
}
} while (!Worklist.empty());
return true;
}
Instruction *InstCombiner::visitAllocSite(Instruction &MI) {
// If we have a malloc call which is only used in any amount of comparisons
// to null and free calls, delete the calls and replace the comparisons with
// true or false as appropriate.
SmallVector<WeakTrackingVH, 64> Users;
if (isAllocSiteRemovable(&MI, Users, TLI)) {
for (unsigned i = 0, e = Users.size(); i != e; ++i) {
Instruction *I = cast_or_null<Instruction>(&*Users[i]);
if (!I) continue;
if (ICmpInst *C = dyn_cast<ICmpInst>(I)) {
ReplaceInstUsesWith(*C,
ConstantInt::get(Type::getInt1Ty(C->getContext()),
C->isFalseWhenEqual()));
} else if (isa<BitCastInst>(I) || isa<GetElementPtrInst>(I)) {
ReplaceInstUsesWith(*I, UndefValue::get(I->getType()));
} else if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I)) {
if (II->getIntrinsicID() == Intrinsic::objectsize) {
ConstantInt *CI = cast<ConstantInt>(II->getArgOperand(1));
uint64_t DontKnow = CI->isZero() ? -1ULL : 0;
ReplaceInstUsesWith(*I, ConstantInt::get(I->getType(), DontKnow));
}
}
EraseInstFromFunction(*I);
}
if (InvokeInst *II = dyn_cast<InvokeInst>(&MI)) {
// Replace invoke with a NOP intrinsic to maintain the original CFG
Module *M = II->getParent()->getParent()->getParent();
Function *F = Intrinsic::getDeclaration(M, Intrinsic::donothing);
InvokeInst::Create(F, II->getNormalDest(), II->getUnwindDest(),
None, "", II->getParent());
}
return EraseInstFromFunction(MI);
}
return nullptr;
}
/// \brief Move the call to free before a NULL test.
///
/// Check if this free is accessed after its argument has been test
/// against NULL (property 0).
/// If yes, it is legal to move this call in its predecessor block.
///
/// The move is performed only if the block containing the call to free
/// will be removed, i.e.:
/// 1. it has only one predecessor P, and P has two successors
/// 2. it contains the call and an unconditional branch
/// 3. its successor is the same as its predecessor's successor
///
/// The profitability is out-of concern here and this function should
/// be called only if the caller knows this transformation would be
/// profitable (e.g., for code size).
static Instruction *
tryToMoveFreeBeforeNullTest(CallInst &FI) {
Value *Op = FI.getArgOperand(0);
BasicBlock *FreeInstrBB = FI.getParent();
BasicBlock *PredBB = FreeInstrBB->getSinglePredecessor();
// Validate part of constraint #1: Only one predecessor
// FIXME: We can extend the number of predecessor, but in that case, we
// would duplicate the call to free in each predecessor and it may
// not be profitable even for code size.
if (!PredBB)
return nullptr;
// Validate constraint #2: Does this block contains only the call to
// free and an unconditional branch?
// FIXME: We could check if we can speculate everything in the
// predecessor block
if (FreeInstrBB->size() != 2)
return nullptr;
BasicBlock *SuccBB;
if (!match(FreeInstrBB->getTerminator(), m_UnconditionalBr(SuccBB)))
return nullptr;
// Validate the rest of constraint #1 by matching on the pred branch.
TerminatorInst *TI = PredBB->getTerminator();
BasicBlock *TrueBB, *FalseBB;
ICmpInst::Predicate Pred;
if (!match(TI, m_Br(m_ICmp(Pred, m_Specific(Op), m_Zero()), TrueBB, FalseBB)))
return nullptr;
if (Pred != ICmpInst::ICMP_EQ && Pred != ICmpInst::ICMP_NE)
return nullptr;
// Validate constraint #3: Ensure the null case just falls through.
if (SuccBB != (Pred == ICmpInst::ICMP_EQ ? TrueBB : FalseBB))
return nullptr;
assert(FreeInstrBB == (Pred == ICmpInst::ICMP_EQ ? FalseBB : TrueBB) &&
"Broken CFG: missing edge from predecessor to successor");
FI.moveBefore(TI);
return &FI;
}
Instruction *InstCombiner::visitFree(CallInst &FI) {
Value *Op = FI.getArgOperand(0);
// free undef -> unreachable.
if (isa<UndefValue>(Op)) {
// Insert a new store to null because we cannot modify the CFG here.
Builder->CreateStore(ConstantInt::getTrue(FI.getContext()),
UndefValue::get(Type::getInt1PtrTy(FI.getContext())));
return EraseInstFromFunction(FI);
}
// If we have 'free null' delete the instruction. This can happen in stl code
// when lots of inlining happens.
if (isa<ConstantPointerNull>(Op))
return EraseInstFromFunction(FI);
// If we optimize for code size, try to move the call to free before the null
// test so that simplify cfg can remove the empty block and dead code
// elimination the branch. I.e., helps to turn something like:
// if (foo) free(foo);
// into
// free(foo);
if (MinimizeSize)
if (Instruction *I = tryToMoveFreeBeforeNullTest(FI))
return I;
return nullptr;
}
Instruction *InstCombiner::visitReturnInst(ReturnInst &RI) {
if (RI.getNumOperands() == 0) // ret void
return nullptr;
Value *ResultOp = RI.getOperand(0);
Type *VTy = ResultOp->getType();
if (!VTy->isIntegerTy())
return nullptr;
// There might be assume intrinsics dominating this return that completely
// determine the value. If so, constant fold it.
unsigned BitWidth = VTy->getPrimitiveSizeInBits();
APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
computeKnownBits(ResultOp, KnownZero, KnownOne, 0, &RI);
if ((KnownZero|KnownOne).isAllOnesValue())
RI.setOperand(0, Constant::getIntegerValue(VTy, KnownOne));
return nullptr;
}
Instruction *InstCombiner::visitBranchInst(BranchInst &BI) {
// Change br (not X), label True, label False to: br X, label False, True
Value *X = nullptr;
BasicBlock *TrueDest;
BasicBlock *FalseDest;
if (match(&BI, m_Br(m_Not(m_Value(X)), TrueDest, FalseDest)) &&
!isa<Constant>(X)) {
// Swap Destinations and condition...
BI.setCondition(X);
BI.swapSuccessors();
return &BI;
}
// If the condition is irrelevant, remove the use so that other
// transforms on the condition become more effective.
if (BI.isConditional() &&
BI.getSuccessor(0) == BI.getSuccessor(1) &&
!isa<UndefValue>(BI.getCondition())) {
BI.setCondition(UndefValue::get(BI.getCondition()->getType()));
return &BI;
}
// Canonicalize fcmp_one -> fcmp_oeq
FCmpInst::Predicate FPred; Value *Y;
if (match(&BI, m_Br(m_FCmp(FPred, m_Value(X), m_Value(Y)),
TrueDest, FalseDest)) &&
BI.getCondition()->hasOneUse())
if (FPred == FCmpInst::FCMP_ONE || FPred == FCmpInst::FCMP_OLE ||
FPred == FCmpInst::FCMP_OGE) {
FCmpInst *Cond = cast<FCmpInst>(BI.getCondition());
Cond->setPredicate(FCmpInst::getInversePredicate(FPred));
// Swap Destinations and condition.
BI.swapSuccessors();
Worklist.Add(Cond);
return &BI;
}
// Canonicalize icmp_ne -> icmp_eq
ICmpInst::Predicate IPred;
if (match(&BI, m_Br(m_ICmp(IPred, m_Value(X), m_Value(Y)),
TrueDest, FalseDest)) &&
BI.getCondition()->hasOneUse())
if (IPred == ICmpInst::ICMP_NE || IPred == ICmpInst::ICMP_ULE ||
IPred == ICmpInst::ICMP_SLE || IPred == ICmpInst::ICMP_UGE ||
IPred == ICmpInst::ICMP_SGE) {
ICmpInst *Cond = cast<ICmpInst>(BI.getCondition());
Cond->setPredicate(ICmpInst::getInversePredicate(IPred));
// Swap Destinations and condition.
BI.swapSuccessors();
Worklist.Add(Cond);
return &BI;
}
return nullptr;
}
Instruction *InstCombiner::visitSwitchInst(SwitchInst &SI) {
Value *Cond = SI.getCondition();
unsigned BitWidth = cast<IntegerType>(Cond->getType())->getBitWidth();
APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
computeKnownBits(Cond, KnownZero, KnownOne, 0, &SI);
unsigned LeadingKnownZeros = KnownZero.countLeadingOnes();
unsigned LeadingKnownOnes = KnownOne.countLeadingOnes();
// Compute the number of leading bits we can ignore.
for (auto &C : SI.cases()) {
LeadingKnownZeros = std::min(
LeadingKnownZeros, C.getCaseValue()->getValue().countLeadingZeros());
LeadingKnownOnes = std::min(
LeadingKnownOnes, C.getCaseValue()->getValue().countLeadingOnes());
}
unsigned NewWidth = BitWidth - std::max(LeadingKnownZeros, LeadingKnownOnes);
// Truncate the condition operand if the new type is equal to or larger than
// the largest legal integer type. We need to be conservative here since
// x86 generates redundant zero-extension instructions if the operand is
// truncated to i8 or i16.
bool TruncCond = false;
if (NewWidth > 0 && BitWidth > NewWidth &&
NewWidth >= DL.getLargestLegalIntTypeSize()) {
TruncCond = true;
IntegerType *Ty = IntegerType::get(SI.getContext(), NewWidth);
Builder->SetInsertPoint(&SI);
Value *NewCond = Builder->CreateTrunc(SI.getCondition(), Ty, "trunc");
SI.setCondition(NewCond);
for (auto &C : SI.cases())
static_cast<SwitchInst::CaseIt *>(&C)->setValue(ConstantInt::get(
SI.getContext(), C.getCaseValue()->getValue().trunc(NewWidth)));
}
if (Instruction *I = dyn_cast<Instruction>(Cond)) {
if (I->getOpcode() == Instruction::Add)
if (ConstantInt *AddRHS = dyn_cast<ConstantInt>(I->getOperand(1))) {
// change 'switch (X+4) case 1:' into 'switch (X) case -3'
// Skip the first item since that's the default case.
for (SwitchInst::CaseIt i = SI.case_begin(), e = SI.case_end();
i != e; ++i) {
ConstantInt* CaseVal = i.getCaseValue();
Constant *LHS = CaseVal;
if (TruncCond)
LHS = LeadingKnownZeros
? ConstantExpr::getZExt(CaseVal, Cond->getType())
: ConstantExpr::getSExt(CaseVal, Cond->getType());
Constant* NewCaseVal = ConstantExpr::getSub(LHS, AddRHS);
assert(isa<ConstantInt>(NewCaseVal) &&
"Result of expression should be constant");
i.setValue(cast<ConstantInt>(NewCaseVal));
}
SI.setCondition(I->getOperand(0));
Worklist.Add(I);
return &SI;
}
}
return TruncCond ? &SI : nullptr;
}
Instruction *InstCombiner::visitExtractValueInst(ExtractValueInst &EV) {
Value *Agg = EV.getAggregateOperand();
if (!EV.hasIndices())
return ReplaceInstUsesWith(EV, Agg);
if (Value *V =
SimplifyExtractValueInst(Agg, EV.getIndices(), DL, TLI, DT, AC))
return ReplaceInstUsesWith(EV, V);
if (InsertValueInst *IV = dyn_cast<InsertValueInst>(Agg)) {
// We're extracting from an insertvalue instruction, compare the indices
const unsigned *exti, *exte, *insi, *inse;
for (exti = EV.idx_begin(), insi = IV->idx_begin(),
exte = EV.idx_end(), inse = IV->idx_end();
exti != exte && insi != inse;
++exti, ++insi) {
if (*insi != *exti)
// The insert and extract both reference distinctly different elements.
// This means the extract is not influenced by the insert, and we can
// replace the aggregate operand of the extract with the aggregate
// operand of the insert. i.e., replace
// %I = insertvalue { i32, { i32 } } %A, { i32 } { i32 42 }, 1
// %E = extractvalue { i32, { i32 } } %I, 0
// with
// %E = extractvalue { i32, { i32 } } %A, 0
return ExtractValueInst::Create(IV->getAggregateOperand(),
EV.getIndices());
}
if (exti == exte && insi == inse)
// Both iterators are at the end: Index lists are identical. Replace
// %B = insertvalue { i32, { i32 } } %A, i32 42, 1, 0
// %C = extractvalue { i32, { i32 } } %B, 1, 0
// with "i32 42"
return ReplaceInstUsesWith(EV, IV->getInsertedValueOperand());
if (exti == exte) {
// The extract list is a prefix of the insert list. i.e. replace
// %I = insertvalue { i32, { i32 } } %A, i32 42, 1, 0
// %E = extractvalue { i32, { i32 } } %I, 1
// with
// %X = extractvalue { i32, { i32 } } %A, 1
// %E = insertvalue { i32 } %X, i32 42, 0
// by switching the order of the insert and extract (though the
// insertvalue should be left in, since it may have other uses).
Value *NewEV = Builder->CreateExtractValue(IV->getAggregateOperand(),
EV.getIndices());
return InsertValueInst::Create(NewEV, IV->getInsertedValueOperand(),
makeArrayRef(insi, inse));
}
if (insi == inse)
// The insert list is a prefix of the extract list
// We can simply remove the common indices from the extract and make it
// operate on the inserted value instead of the insertvalue result.
// i.e., replace
// %I = insertvalue { i32, { i32 } } %A, { i32 } { i32 42 }, 1
// %E = extractvalue { i32, { i32 } } %I, 1, 0
// with
// %E extractvalue { i32 } { i32 42 }, 0
return ExtractValueInst::Create(IV->getInsertedValueOperand(),
makeArrayRef(exti, exte));
}
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(Agg)) {
// We're extracting from an intrinsic, see if we're the only user, which
// allows us to simplify multiple result intrinsics to simpler things that
// just get one value.
if (II->hasOneUse()) {
// Check if we're grabbing the overflow bit or the result of a 'with
// overflow' intrinsic. If it's the latter we can remove the intrinsic
// and replace it with a traditional binary instruction.
switch (II->getIntrinsicID()) {
case Intrinsic::uadd_with_overflow:
case Intrinsic::sadd_with_overflow:
if (*EV.idx_begin() == 0) { // Normal result.
Value *LHS = II->getArgOperand(0), *RHS = II->getArgOperand(1);
ReplaceInstUsesWith(*II, UndefValue::get(II->getType()));
EraseInstFromFunction(*II);
return BinaryOperator::CreateAdd(LHS, RHS);
}
// If the normal result of the add is dead, and the RHS is a constant,
// we can transform this into a range comparison.
// overflow = uadd a, -4 --> overflow = icmp ugt a, 3
if (II->getIntrinsicID() == Intrinsic::uadd_with_overflow)
if (ConstantInt *CI = dyn_cast<ConstantInt>(II->getArgOperand(1)))
return new ICmpInst(ICmpInst::ICMP_UGT, II->getArgOperand(0),
ConstantExpr::getNot(CI));
break;
case Intrinsic::usub_with_overflow:
case Intrinsic::ssub_with_overflow:
if (*EV.idx_begin() == 0) { // Normal result.
Value *LHS = II->getArgOperand(0), *RHS = II->getArgOperand(1);
ReplaceInstUsesWith(*II, UndefValue::get(II->getType()));
EraseInstFromFunction(*II);
return BinaryOperator::CreateSub(LHS, RHS);
}
break;
case Intrinsic::umul_with_overflow:
case Intrinsic::smul_with_overflow:
if (*EV.idx_begin() == 0) { // Normal result.
Value *LHS = II->getArgOperand(0), *RHS = II->getArgOperand(1);
ReplaceInstUsesWith(*II, UndefValue::get(II->getType()));
EraseInstFromFunction(*II);
return BinaryOperator::CreateMul(LHS, RHS);
}
break;
default:
break;
}
}
}
if (LoadInst *L = dyn_cast<LoadInst>(Agg))
// If the (non-volatile) load only has one use, we can rewrite this to a
// load from a GEP. This reduces the size of the load.
// FIXME: If a load is used only by extractvalue instructions then this
// could be done regardless of having multiple uses.
if (L->isSimple() && L->hasOneUse()) {
// extractvalue has integer indices, getelementptr has Value*s. Convert.
SmallVector<Value*, 4> Indices;
// Prefix an i32 0 since we need the first element.
Indices.push_back(Builder->getInt32(0));
for (ExtractValueInst::idx_iterator I = EV.idx_begin(), E = EV.idx_end();
I != E; ++I)
Indices.push_back(Builder->getInt32(*I));
// We need to insert these at the location of the old load, not at that of
// the extractvalue.
Builder->SetInsertPoint(L->getParent(), L);
Value *GEP = Builder->CreateInBoundsGEP(L->getType(),
L->getPointerOperand(), Indices);
// Returning the load directly will cause the main loop to insert it in
// the wrong spot, so use ReplaceInstUsesWith().
return ReplaceInstUsesWith(EV, Builder->CreateLoad(GEP));
}
// We could simplify extracts from other values. Note that nested extracts may
// already be simplified implicitly by the above: extract (extract (insert) )
// will be translated into extract ( insert ( extract ) ) first and then just
// the value inserted, if appropriate. Similarly for extracts from single-use
// loads: extract (extract (load)) will be translated to extract (load (gep))
// and if again single-use then via load (gep (gep)) to load (gep).
// However, double extracts from e.g. function arguments or return values
// aren't handled yet.
return nullptr;
}
/// isCatchAll - Return 'true' if the given typeinfo will match anything.
static bool isCatchAll(EHPersonality Personality, Constant *TypeInfo) {
switch (Personality) {
case EHPersonality::GNU_C:
// The GCC C EH personality only exists to support cleanups, so it's not
// clear what the semantics of catch clauses are.
return false;
case EHPersonality::Unknown:
return false;
case EHPersonality::GNU_Ada:
// While __gnat_all_others_value will match any Ada exception, it doesn't
// match foreign exceptions (or didn't, before gcc-4.7).
return false;
case EHPersonality::GNU_CXX:
case EHPersonality::GNU_ObjC:
case EHPersonality::MSVC_X86SEH:
case EHPersonality::MSVC_Win64SEH:
case EHPersonality::MSVC_CXX:
return TypeInfo->isNullValue();
}
llvm_unreachable("invalid enum");
}
static bool shorter_filter(const Value *LHS, const Value *RHS) {
return
cast<ArrayType>(LHS->getType())->getNumElements()
<
cast<ArrayType>(RHS->getType())->getNumElements();
}
Instruction *InstCombiner::visitLandingPadInst(LandingPadInst &LI) {
// The logic here should be correct for any real-world personality function.
// However if that turns out not to be true, the offending logic can always
// be conditioned on the personality function, like the catch-all logic is.
EHPersonality Personality =
classifyEHPersonality(LI.getParent()->getParent()->getPersonalityFn());
// Simplify the list of clauses, eg by removing repeated catch clauses
// (these are often created by inlining).
bool MakeNewInstruction = false; // If true, recreate using the following:
SmallVector<Constant *, 16> NewClauses; // - Clauses for the new instruction;
bool CleanupFlag = LI.isCleanup(); // - The new instruction is a cleanup.
SmallPtrSet<Value *, 16> AlreadyCaught; // Typeinfos known caught already.
for (unsigned i = 0, e = LI.getNumClauses(); i != e; ++i) {
bool isLastClause = i + 1 == e;
if (LI.isCatch(i)) {
// A catch clause.
Constant *CatchClause = LI.getClause(i);
Constant *TypeInfo = CatchClause->stripPointerCasts();
// If we already saw this clause, there is no point in having a second
// copy of it.
if (AlreadyCaught.insert(TypeInfo).second) {
// This catch clause was not already seen.
NewClauses.push_back(CatchClause);
} else {
// Repeated catch clause - drop the redundant copy.
MakeNewInstruction = true;
}
// If this is a catch-all then there is no point in keeping any following
// clauses or marking the landingpad as having a cleanup.
if (isCatchAll(Personality, TypeInfo)) {
if (!isLastClause)
MakeNewInstruction = true;
CleanupFlag = false;
break;
}
} else {
// A filter clause. If any of the filter elements were already caught
// then they can be dropped from the filter. It is tempting to try to
// exploit the filter further by saying that any typeinfo that does not
// occur in the filter can't be caught later (and thus can be dropped).
// However this would be wrong, since typeinfos can match without being
// equal (for example if one represents a C++ class, and the other some
// class derived from it).
assert(LI.isFilter(i) && "Unsupported landingpad clause!");
Constant *FilterClause = LI.getClause(i);
ArrayType *FilterType = cast<ArrayType>(FilterClause->getType());
unsigned NumTypeInfos = FilterType->getNumElements();
// An empty filter catches everything, so there is no point in keeping any
// following clauses or marking the landingpad as having a cleanup. By
// dealing with this case here the following code is made a bit simpler.
if (!NumTypeInfos) {
NewClauses.push_back(FilterClause);
if (!isLastClause)
MakeNewInstruction = true;
CleanupFlag = false;
break;
}
bool MakeNewFilter = false; // If true, make a new filter.
SmallVector<Constant *, 16> NewFilterElts; // New elements.
if (isa<ConstantAggregateZero>(FilterClause)) {
// Not an empty filter - it contains at least one null typeinfo.
assert(NumTypeInfos > 0 && "Should have handled empty filter already!");
Constant *TypeInfo =
Constant::getNullValue(FilterType->getElementType());
// If this typeinfo is a catch-all then the filter can never match.
if (isCatchAll(Personality, TypeInfo)) {
// Throw the filter away.
MakeNewInstruction = true;
continue;
}
// There is no point in having multiple copies of this typeinfo, so
// discard all but the first copy if there is more than one.
NewFilterElts.push_back(TypeInfo);
if (NumTypeInfos > 1)
MakeNewFilter = true;
} else {
ConstantArray *Filter = cast<ConstantArray>(FilterClause);
SmallPtrSet<Value *, 16> SeenInFilter; // For uniquing the elements.
NewFilterElts.reserve(NumTypeInfos);
// Remove any filter elements that were already caught or that already
// occurred in the filter. While there, see if any of the elements are
// catch-alls. If so, the filter can be discarded.
bool SawCatchAll = false;
for (unsigned j = 0; j != NumTypeInfos; ++j) {
Constant *Elt = Filter->getOperand(j);
Constant *TypeInfo = Elt->stripPointerCasts();
if (isCatchAll(Personality, TypeInfo)) {
// This element is a catch-all. Bail out, noting this fact.
SawCatchAll = true;
break;
}
if (AlreadyCaught.count(TypeInfo))
// Already caught by an earlier clause, so having it in the filter
// is pointless.
continue;
// There is no point in having multiple copies of the same typeinfo in
// a filter, so only add it if we didn't already.
if (SeenInFilter.insert(TypeInfo).second)
NewFilterElts.push_back(cast<Constant>(Elt));
}
// A filter containing a catch-all cannot match anything by definition.
if (SawCatchAll) {
// Throw the filter away.
MakeNewInstruction = true;
continue;
}
// If we dropped something from the filter, make a new one.
if (NewFilterElts.size() < NumTypeInfos)
MakeNewFilter = true;
}
if (MakeNewFilter) {
FilterType = ArrayType::get(FilterType->getElementType(),
NewFilterElts.size());
FilterClause = ConstantArray::get(FilterType, NewFilterElts);
MakeNewInstruction = true;
}
NewClauses.push_back(FilterClause);
// If the new filter is empty then it will catch everything so there is
// no point in keeping any following clauses or marking the landingpad
// as having a cleanup. The case of the original filter being empty was
// already handled above.
if (MakeNewFilter && !NewFilterElts.size()) {
assert(MakeNewInstruction && "New filter but not a new instruction!");
CleanupFlag = false;
break;
}
}
}
// If several filters occur in a row then reorder them so that the shortest
// filters come first (those with the smallest number of elements). This is
// advantageous because shorter filters are more likely to match, speeding up
// unwinding, but mostly because it increases the effectiveness of the other
// filter optimizations below.
for (unsigned i = 0, e = NewClauses.size(); i + 1 < e; ) {
unsigned j;
// Find the maximal 'j' s.t. the range [i, j) consists entirely of filters.
for (j = i; j != e; ++j)
if (!isa<ArrayType>(NewClauses[j]->getType()))
break;
// Check whether the filters are already sorted by length. We need to know
// if sorting them is actually going to do anything so that we only make a
// new landingpad instruction if it does.
for (unsigned k = i; k + 1 < j; ++k)
if (shorter_filter(NewClauses[k+1], NewClauses[k])) {
// Not sorted, so sort the filters now. Doing an unstable sort would be
// correct too but reordering filters pointlessly might confuse users.
std::stable_sort(NewClauses.begin() + i, NewClauses.begin() + j,
shorter_filter);
MakeNewInstruction = true;
break;
}
// Look for the next batch of filters.
i = j + 1;
}
// If typeinfos matched if and only if equal, then the elements of a filter L
// that occurs later than a filter F could be replaced by the intersection of
// the elements of F and L. In reality two typeinfos can match without being
// equal (for example if one represents a C++ class, and the other some class
// derived from it) so it would be wrong to perform this transform in general.
// However the transform is correct and useful if F is a subset of L. In that
// case L can be replaced by F, and thus removed altogether since repeating a
// filter is pointless. So here we look at all pairs of filters F and L where
// L follows F in the list of clauses, and remove L if every element of F is
// an element of L. This can occur when inlining C++ functions with exception
// specifications.
for (unsigned i = 0; i + 1 < NewClauses.size(); ++i) {
// Examine each filter in turn.
Value *Filter = NewClauses[i];
ArrayType *FTy = dyn_cast<ArrayType>(Filter->getType());
if (!FTy)
// Not a filter - skip it.
continue;
unsigned FElts = FTy->getNumElements();
// Examine each filter following this one. Doing this backwards means that
// we don't have to worry about filters disappearing under us when removed.
for (unsigned j = NewClauses.size() - 1; j != i; --j) {
Value *LFilter = NewClauses[j];
ArrayType *LTy = dyn_cast<ArrayType>(LFilter->getType());
if (!LTy)
// Not a filter - skip it.
continue;
// If Filter is a subset of LFilter, i.e. every element of Filter is also
// an element of LFilter, then discard LFilter.
SmallVectorImpl<Constant *>::iterator J = NewClauses.begin() + j;
// If Filter is empty then it is a subset of LFilter.
if (!FElts) {
// Discard LFilter.
NewClauses.erase(J);
MakeNewInstruction = true;
// Move on to the next filter.
continue;
}
unsigned LElts = LTy->getNumElements();
// If Filter is longer than LFilter then it cannot be a subset of it.
if (FElts > LElts)
// Move on to the next filter.
continue;
// At this point we know that LFilter has at least one element.
if (isa<ConstantAggregateZero>(LFilter)) { // LFilter only contains zeros.
// Filter is a subset of LFilter iff Filter contains only zeros (as we
// already know that Filter is not longer than LFilter).
if (isa<ConstantAggregateZero>(Filter)) {
assert(FElts <= LElts && "Should have handled this case earlier!");
// Discard LFilter.
NewClauses.erase(J);
MakeNewInstruction = true;
}
// Move on to the next filter.
continue;
}
ConstantArray *LArray = cast<ConstantArray>(LFilter);
if (isa<ConstantAggregateZero>(Filter)) { // Filter only contains zeros.
// Since Filter is non-empty and contains only zeros, it is a subset of
// LFilter iff LFilter contains a zero.
assert(FElts > 0 && "Should have eliminated the empty filter earlier!");
for (unsigned l = 0; l != LElts; ++l)
if (LArray->getOperand(l)->isNullValue()) {
// LFilter contains a zero - discard it.
NewClauses.erase(J);
MakeNewInstruction = true;
break;
}
// Move on to the next filter.
continue;
}
// At this point we know that both filters are ConstantArrays. Loop over
// operands to see whether every element of Filter is also an element of
// LFilter. Since filters tend to be short this is probably faster than
// using a method that scales nicely.
ConstantArray *FArray = cast<ConstantArray>(Filter);
bool AllFound = true;
for (unsigned f = 0; f != FElts; ++f) {
Value *FTypeInfo = FArray->getOperand(f)->stripPointerCasts();
AllFound = false;
for (unsigned l = 0; l != LElts; ++l) {
Value *LTypeInfo = LArray->getOperand(l)->stripPointerCasts();
if (LTypeInfo == FTypeInfo) {
AllFound = true;
break;
}
}
if (!AllFound)
break;
}
if (AllFound) {
// Discard LFilter.
NewClauses.erase(J);
MakeNewInstruction = true;
}
// Move on to the next filter.
}
}
// If we changed any of the clauses, replace the old landingpad instruction
// with a new one.
if (MakeNewInstruction) {
LandingPadInst *NLI = LandingPadInst::Create(LI.getType(),
NewClauses.size());
for (unsigned i = 0, e = NewClauses.size(); i != e; ++i)
NLI->addClause(NewClauses[i]);
// A landing pad with no clauses must have the cleanup flag set. It is
// theoretically possible, though highly unlikely, that we eliminated all
// clauses. If so, force the cleanup flag to true.
if (NewClauses.empty())
CleanupFlag = true;
NLI->setCleanup(CleanupFlag);
return NLI;
}
// Even if none of the clauses changed, we may nonetheless have understood
// that the cleanup flag is pointless. Clear it if so.
if (LI.isCleanup() != CleanupFlag) {
assert(!CleanupFlag && "Adding a cleanup, not removing one?!");
LI.setCleanup(CleanupFlag);
return &LI;
}
return nullptr;
}
/// TryToSinkInstruction - Try to move the specified instruction from its
/// current block into the beginning of DestBlock, which can only happen if it's
/// safe to move the instruction past all of the instructions between it and the
/// end of its block.
static bool TryToSinkInstruction(Instruction *I, BasicBlock *DestBlock) {
assert(I->hasOneUse() && "Invariants didn't hold!");
// Cannot move control-flow-involving, volatile loads, vaarg, etc.
if (isa<PHINode>(I) || isa<LandingPadInst>(I) || I->mayHaveSideEffects() ||
isa<TerminatorInst>(I))
return false;
// Do not sink alloca instructions out of the entry block.
if (isa<AllocaInst>(I) && I->getParent() ==
&DestBlock->getParent()->getEntryBlock())
return false;
// We can only sink load instructions if there is nothing between the load and
// the end of block that could change the value.
if (I->mayReadFromMemory()) {
for (BasicBlock::iterator Scan = I, E = I->getParent()->end();
Scan != E; ++Scan)
if (Scan->mayWriteToMemory())
return false;
}
BasicBlock::iterator InsertPos = DestBlock->getFirstInsertionPt();
I->moveBefore(InsertPos);
++NumSunkInst;
return true;
}
bool InstCombiner::run() {
while (!Worklist.isEmpty()) {
Instruction *I = Worklist.RemoveOne();
if (I == nullptr) continue; // skip null values.
// Check to see if we can DCE the instruction.
if (isInstructionTriviallyDead(I, TLI)) {
DEBUG(dbgs() << "IC: DCE: " << *I << '\n');
EraseInstFromFunction(*I);
++NumDeadInst;
MadeIRChange = true;
continue;
}
// Instruction isn't dead, see if we can constant propagate it.
if (!I->use_empty() &&
(I->getNumOperands() == 0 || isa<Constant>(I->getOperand(0)))) {
if (Constant *C = ConstantFoldInstruction(I, DL, TLI)) {
DEBUG(dbgs() << "IC: ConstFold to: " << *C << " from: " << *I << '\n');
// Add operands to the worklist.
ReplaceInstUsesWith(*I, C);
++NumConstProp;
EraseInstFromFunction(*I);
MadeIRChange = true;
continue;
}
}
// See if we can trivially sink this instruction to a successor basic block.
if (I->hasOneUse()) {
BasicBlock *BB = I->getParent();
Instruction *UserInst = cast<Instruction>(*I->user_begin());
BasicBlock *UserParent;
// Get the block the use occurs in.
if (PHINode *PN = dyn_cast<PHINode>(UserInst))
UserParent = PN->getIncomingBlock(*I->use_begin());
else
UserParent = UserInst->getParent();
if (UserParent != BB) {
bool UserIsSuccessor = false;
// See if the user is one of our successors.
for (succ_iterator SI = succ_begin(BB), E = succ_end(BB); SI != E; ++SI)
if (*SI == UserParent) {
UserIsSuccessor = true;
break;
}
// If the user is one of our immediate successors, and if that successor
// only has us as a predecessors (we'd have to split the critical edge
// otherwise), we can keep going.
if (UserIsSuccessor && UserParent->getSinglePredecessor()) {
if (!m_HLSLNoSinks) // HLSL Change
// Okay, the CFG is simple enough, try to sink this instruction.
if (TryToSinkInstruction(I, UserParent)) {
MadeIRChange = true;
// We'll add uses of the sunk instruction below, but since sinking
// can expose opportunities for it's *operands* add them to the
// worklist
for (Use &U : I->operands())
if (Instruction *OpI = dyn_cast<Instruction>(U.get()))
Worklist.Add(OpI);
}
}
}
}
// Now that we have an instruction, try combining it to simplify it.
Builder->SetInsertPoint(I->getParent(), I);
Builder->SetCurrentDebugLocation(I->getDebugLoc());
#ifndef NDEBUG
std::string OrigI;
#endif
DEBUG(raw_string_ostream SS(OrigI); I->print(SS); OrigI = SS.str(););
DEBUG(dbgs() << "IC: Visiting: " << OrigI << '\n');
if (Instruction *Result = visit(*I)) {
++NumCombined;
// Should we replace the old instruction with a new one?
if (Result != I) {
DEBUG(dbgs() << "IC: Old = " << *I << '\n'
<< " New = " << *Result << '\n');
if (I->getDebugLoc())
Result->setDebugLoc(I->getDebugLoc());
// Everything uses the new instruction now.
I->replaceAllUsesWith(Result);
// Move the name to the new instruction first.
Result->takeName(I);
// Push the new instruction and any users onto the worklist.
Worklist.Add(Result);
Worklist.AddUsersToWorkList(*Result);
// Insert the new instruction into the basic block...
BasicBlock *InstParent = I->getParent();
BasicBlock::iterator InsertPos = I;
// If we replace a PHI with something that isn't a PHI, fix up the
// insertion point.
if (!isa<PHINode>(Result) && isa<PHINode>(InsertPos))
InsertPos = InstParent->getFirstInsertionPt();
InstParent->getInstList().insert(InsertPos, Result);
EraseInstFromFunction(*I);
} else {
#ifndef NDEBUG
DEBUG(dbgs() << "IC: Mod = " << OrigI << '\n'
<< " New = " << *I << '\n');
#endif
// If the instruction was modified, it's possible that it is now dead.
// if so, remove it.
if (isInstructionTriviallyDead(I, TLI)) {
EraseInstFromFunction(*I);
} else {
Worklist.Add(I);
Worklist.AddUsersToWorkList(*I);
}
}
MadeIRChange = true;
}
}
Worklist.Zap();
return MadeIRChange;
}
/// AddReachableCodeToWorklist - Walk the function in depth-first order, adding
/// all reachable code to the worklist.
///
/// This has a couple of tricks to make the code faster and more powerful. In
/// particular, we constant fold and DCE instructions as we go, to avoid adding
/// them to the worklist (this significantly speeds up instcombine on code where
/// many instructions are dead or constant). Additionally, if we find a branch
/// whose condition is a known constant, we only visit the reachable successors.
///
static bool AddReachableCodeToWorklist(BasicBlock *BB, const DataLayout &DL,
SmallPtrSetImpl<BasicBlock *> &Visited,
InstCombineWorklist &ICWorklist,
const TargetLibraryInfo *TLI) {
bool MadeIRChange = false;
SmallVector<BasicBlock*, 256> Worklist;
Worklist.push_back(BB);
SmallVector<Instruction*, 128> InstrsForInstCombineWorklist;
DenseMap<ConstantExpr*, Constant*> FoldedConstants;
do {
BB = Worklist.pop_back_val();
// We have now visited this block! If we've already been here, ignore it.
if (!Visited.insert(BB).second)
continue;
for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E; ) {
Instruction *Inst = BBI++;
// DCE instruction if trivially dead.
if (isInstructionTriviallyDead(Inst, TLI)) {
++NumDeadInst;
DEBUG(dbgs() << "IC: DCE: " << *Inst << '\n');
Inst->eraseFromParent();
continue;
}
// ConstantProp instruction if trivially constant.
if (!Inst->use_empty() &&
(Inst->getNumOperands() == 0 || isa<Constant>(Inst->getOperand(0))))
if (Constant *C = ConstantFoldInstruction(Inst, DL, TLI)) {
DEBUG(dbgs() << "IC: ConstFold to: " << *C << " from: "
<< *Inst << '\n');
Inst->replaceAllUsesWith(C);
++NumConstProp;
Inst->eraseFromParent();
continue;
}
// See if we can constant fold its operands.
for (User::op_iterator i = Inst->op_begin(), e = Inst->op_end(); i != e;
++i) {
ConstantExpr *CE = dyn_cast<ConstantExpr>(i);
if (CE == nullptr)
continue;
Constant *&FoldRes = FoldedConstants[CE];
if (!FoldRes)
FoldRes = ConstantFoldConstantExpression(CE, DL, TLI);
if (!FoldRes)
FoldRes = CE;
if (FoldRes != CE) {
*i = FoldRes;
MadeIRChange = true;
}
}
InstrsForInstCombineWorklist.push_back(Inst);
}
// Recursively visit successors. If this is a branch or switch on a
// constant, only visit the reachable successor.
TerminatorInst *TI = BB->getTerminator();
if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
if (BI->isConditional() && isa<ConstantInt>(BI->getCondition())) {
bool CondVal = cast<ConstantInt>(BI->getCondition())->getZExtValue();
BasicBlock *ReachableBB = BI->getSuccessor(!CondVal);
Worklist.push_back(ReachableBB);
continue;
}
} else if (SwitchInst *SI = dyn_cast<SwitchInst>(TI)) {
if (ConstantInt *Cond = dyn_cast<ConstantInt>(SI->getCondition())) {
// See if this is an explicit destination.
for (SwitchInst::CaseIt i = SI->case_begin(), e = SI->case_end();
i != e; ++i)
if (i.getCaseValue() == Cond) {
BasicBlock *ReachableBB = i.getCaseSuccessor();
Worklist.push_back(ReachableBB);
continue;
}
// Otherwise it is the default destination.
Worklist.push_back(SI->getDefaultDest());
continue;
}
}
for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
Worklist.push_back(TI->getSuccessor(i));
} while (!Worklist.empty());
// Once we've found all of the instructions to add to instcombine's worklist,
// add them in reverse order. This way instcombine will visit from the top
// of the function down. This jives well with the way that it adds all uses
// of instructions to the worklist after doing a transformation, thus avoiding
// some N^2 behavior in pathological cases.
ICWorklist.AddInitialGroup(&InstrsForInstCombineWorklist[0],
InstrsForInstCombineWorklist.size());
return MadeIRChange;
}
/// \brief Populate the IC worklist from a function, and prune any dead basic
/// blocks discovered in the process.
///
/// This also does basic constant propagation and other forward fixing to make
/// the combiner itself run much faster.
static bool prepareICWorklistFromFunction(Function &F, const DataLayout &DL,
TargetLibraryInfo *TLI,
InstCombineWorklist &ICWorklist) {
bool MadeIRChange = false;
// Do a depth-first traversal of the function, populate the worklist with
// the reachable instructions. Ignore blocks that are not reachable. Keep
// track of which blocks we visit.
SmallPtrSet<BasicBlock *, 64> Visited;
MadeIRChange |=
AddReachableCodeToWorklist(F.begin(), DL, Visited, ICWorklist, TLI);
// Do a quick scan over the function. If we find any blocks that are
// unreachable, remove any instructions inside of them. This prevents
// the instcombine code from having to deal with some bad special cases.
for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) {
if (Visited.count(BB))
continue;
// Delete the instructions backwards, as it has a reduced likelihood of
// having to update as many def-use and use-def chains.
Instruction *EndInst = BB->getTerminator(); // Last not to be deleted.
while (EndInst != BB->begin()) {
// Delete the next to last instruction.
BasicBlock::iterator I = EndInst;
Instruction *Inst = --I;
if (!Inst->use_empty())
Inst->replaceAllUsesWith(UndefValue::get(Inst->getType()));
if (isa<LandingPadInst>(Inst)) {
EndInst = Inst;
continue;
}
if (!isa<DbgInfoIntrinsic>(Inst)) {
++NumDeadInst;
MadeIRChange = true;
}
Inst->eraseFromParent();
}
}
return MadeIRChange;
}
static bool
combineInstructionsOverFunction(Function &F, InstCombineWorklist &Worklist, bool HLSLNoSink/*HLSL Change*/,
AliasAnalysis *AA, AssumptionCache &AC,
TargetLibraryInfo &TLI, DominatorTree &DT,
LoopInfo *LI = nullptr) {
// Minimizing size?
bool MinimizeSize = F.hasFnAttribute(Attribute::MinSize);
auto &DL = F.getParent()->getDataLayout();
/// Builder - This is an IRBuilder that automatically inserts new
/// instructions into the worklist when they are created.
IRBuilder<true, TargetFolder, InstCombineIRInserter> Builder(
F.getContext(), TargetFolder(DL), InstCombineIRInserter(Worklist, &AC));
// Lower dbg.declare intrinsics otherwise their value may be clobbered
// by instcombiner.
bool DbgDeclaresChanged = LowerDbgDeclare(F);
// Iterate while there is work to do.
int Iteration = 0;
for (;;) {
++Iteration;
DEBUG(dbgs() << "\n\nINSTCOMBINE ITERATION #" << Iteration << " on "
<< F.getName() << "\n");
bool Changed = false;
if (prepareICWorklistFromFunction(F, DL, &TLI, Worklist))
Changed = true;
InstCombiner IC(Worklist, &Builder, MinimizeSize,
AA, &AC, &TLI, &DT, DL, LI);
IC.m_HLSLNoSinks = HLSLNoSink;
if (IC.run())
Changed = true;
if (!Changed)
break;
}
return DbgDeclaresChanged || Iteration > 1;
}
PreservedAnalyses InstCombinePass::run(Function &F,
AnalysisManager<Function> *AM) {
auto &AC = AM->getResult<AssumptionAnalysis>(F);
auto &DT = AM->getResult<DominatorTreeAnalysis>(F);
auto &TLI = AM->getResult<TargetLibraryAnalysis>(F);
auto *LI = AM->getCachedResult<LoopAnalysis>(F);
// FIXME: The AliasAnalysis is not yet supported in the new pass manager
if (!combineInstructionsOverFunction(F, Worklist, /*HLSLNoSink*/false, nullptr, AC, TLI, DT, LI))
// No changes, all analyses are preserved.
return PreservedAnalyses::all();
// Mark all the analyses that instcombine updates as preserved.
// FIXME: Need a way to preserve CFG analyses here!
PreservedAnalyses PA;
PA.preserve<DominatorTreeAnalysis>();
return PA;
}
namespace {
/// \brief The legacy pass manager's instcombine pass.
///
/// This is a basic whole-function wrapper around the instcombine utility. It
/// will try to combine all instructions in the function.
class InstructionCombiningPass : public FunctionPass {
InstCombineWorklist Worklist;
public:
static char ID; // Pass identification, replacement for typeid
InstructionCombiningPass() : FunctionPass(ID) {
initializeInstructionCombiningPassPass(*PassRegistry::getPassRegistry());
}
// HLSL Change - begin
bool m_HLSLNoSink = false;
InstructionCombiningPass(bool HLSLNoSink) : FunctionPass(ID) {
initializeInstructionCombiningPassPass(*PassRegistry::getPassRegistry());
m_HLSLNoSink = HLSLNoSink;
}
void applyOptions(PassOptions O) override {
GetPassOptionBool(O, "NoSink", &m_HLSLNoSink, /*defaultValue*/false);
}
void dumpConfig(raw_ostream &OS) override {
FunctionPass::dumpConfig(OS);
OS << ",NoSink=" << m_HLSLNoSink;
}
// HLSL Change - end
void getAnalysisUsage(AnalysisUsage &AU) const override;
bool runOnFunction(Function &F) override;
};
}
void InstructionCombiningPass::getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesCFG();
AU.addRequired<AliasAnalysis>();
AU.addRequired<AssumptionCacheTracker>();
AU.addRequired<TargetLibraryInfoWrapperPass>();
AU.addRequired<DominatorTreeWrapperPass>();
AU.addPreserved<DominatorTreeWrapperPass>();
}
bool InstructionCombiningPass::runOnFunction(Function &F) {
if (skipOptnoneFunction(F))
return false;
// Required analyses.
auto AA = &getAnalysis<AliasAnalysis>();
auto &AC = getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
auto &TLI = getAnalysis<TargetLibraryInfoWrapperPass>().getTLI();
auto &DT = getAnalysis<DominatorTreeWrapperPass>().getDomTree();
// Optional analyses.
auto *LIWP = getAnalysisIfAvailable<LoopInfoWrapperPass>();
auto *LI = LIWP ? &LIWP->getLoopInfo() : nullptr;
return combineInstructionsOverFunction(F, Worklist, m_HLSLNoSink /*HLSL Change*/, AA, AC, TLI, DT, LI);
}
char InstructionCombiningPass::ID = 0;
INITIALIZE_PASS_BEGIN(InstructionCombiningPass, "instcombine",
"Combine redundant instructions", false, false)
INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)
INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_AG_DEPENDENCY(AliasAnalysis)
INITIALIZE_PASS_END(InstructionCombiningPass, "instcombine",
"Combine redundant instructions", false, false)
// Initialization Routines
void llvm::initializeInstCombine(PassRegistry &Registry) {
initializeInstructionCombiningPassPass(Registry);
}
void LLVMInitializeInstCombine(LLVMPassRegistryRef R) {
initializeInstructionCombiningPassPass(*unwrap(R));
}
FunctionPass *llvm::createInstructionCombiningPass() {
return new InstructionCombiningPass();
}
// HLSL Change - begin
FunctionPass *llvm::createInstructionCombiningPass(bool HLSLNoSink) {
return new InstructionCombiningPass(HLSLNoSink);
}
// HLSL Change - end
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp | //===- InstCombineAndOrXor.cpp --------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the visitAnd, visitOr, and visitXor functions.
//
//===----------------------------------------------------------------------===//
#include "InstCombineInternal.h"
#include "llvm/ADT/Triple.h" // HLSL Change
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/IR/ConstantRange.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/Transforms/Utils/CmpInstAnalysis.h"
using namespace llvm;
using namespace PatternMatch;
#define DEBUG_TYPE "instcombine"
static inline Value *dyn_castNotVal(Value *V) {
// If this is not(not(x)) don't return that this is a not: we want the two
// not's to be folded first.
if (BinaryOperator::isNot(V)) {
Value *Operand = BinaryOperator::getNotArgument(V);
if (!IsFreeToInvert(Operand, Operand->hasOneUse()))
return Operand;
}
// Constants can be considered to be not'ed values...
if (ConstantInt *C = dyn_cast<ConstantInt>(V))
return ConstantInt::get(C->getType(), ~C->getValue());
return nullptr;
}
/// getFCmpCode - Similar to getICmpCode but for FCmpInst. This encodes a fcmp
/// predicate into a three bit mask. It also returns whether it is an ordered
/// predicate by reference.
static unsigned getFCmpCode(FCmpInst::Predicate CC, bool &isOrdered) {
isOrdered = false;
switch (CC) {
case FCmpInst::FCMP_ORD: isOrdered = true; return 0; // 000
case FCmpInst::FCMP_UNO: return 0; // 000
case FCmpInst::FCMP_OGT: isOrdered = true; return 1; // 001
case FCmpInst::FCMP_UGT: return 1; // 001
case FCmpInst::FCMP_OEQ: isOrdered = true; return 2; // 010
case FCmpInst::FCMP_UEQ: return 2; // 010
case FCmpInst::FCMP_OGE: isOrdered = true; return 3; // 011
case FCmpInst::FCMP_UGE: return 3; // 011
case FCmpInst::FCMP_OLT: isOrdered = true; return 4; // 100
case FCmpInst::FCMP_ULT: return 4; // 100
case FCmpInst::FCMP_ONE: isOrdered = true; return 5; // 101
case FCmpInst::FCMP_UNE: return 5; // 101
case FCmpInst::FCMP_OLE: isOrdered = true; return 6; // 110
case FCmpInst::FCMP_ULE: return 6; // 110
// True -> 7
default:
// Not expecting FCMP_FALSE and FCMP_TRUE;
llvm_unreachable("Unexpected FCmp predicate!");
}
}
/// getNewICmpValue - This is the complement of getICmpCode, which turns an
/// opcode and two operands into either a constant true or false, or a brand
/// new ICmp instruction. The sign is passed in to determine which kind
/// of predicate to use in the new icmp instruction.
static Value *getNewICmpValue(bool Sign, unsigned Code, Value *LHS, Value *RHS,
InstCombiner::BuilderTy *Builder) {
ICmpInst::Predicate NewPred;
if (Value *NewConstant = getICmpValue(Sign, Code, LHS, RHS, NewPred))
return NewConstant;
return Builder->CreateICmp(NewPred, LHS, RHS);
}
/// getFCmpValue - This is the complement of getFCmpCode, which turns an
/// opcode and two operands into either a FCmp instruction. isordered is passed
/// in to determine which kind of predicate to use in the new fcmp instruction.
static Value *getFCmpValue(bool isordered, unsigned code,
Value *LHS, Value *RHS,
InstCombiner::BuilderTy *Builder) {
CmpInst::Predicate Pred;
switch (code) {
default: llvm_unreachable("Illegal FCmp code!");
case 0: Pred = isordered ? FCmpInst::FCMP_ORD : FCmpInst::FCMP_UNO; break;
case 1: Pred = isordered ? FCmpInst::FCMP_OGT : FCmpInst::FCMP_UGT; break;
case 2: Pred = isordered ? FCmpInst::FCMP_OEQ : FCmpInst::FCMP_UEQ; break;
case 3: Pred = isordered ? FCmpInst::FCMP_OGE : FCmpInst::FCMP_UGE; break;
case 4: Pred = isordered ? FCmpInst::FCMP_OLT : FCmpInst::FCMP_ULT; break;
case 5: Pred = isordered ? FCmpInst::FCMP_ONE : FCmpInst::FCMP_UNE; break;
case 6: Pred = isordered ? FCmpInst::FCMP_OLE : FCmpInst::FCMP_ULE; break;
case 7:
if (!isordered)
return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 1);
Pred = FCmpInst::FCMP_ORD; break;
}
return Builder->CreateFCmp(Pred, LHS, RHS);
}
/// \brief Transform BITWISE_OP(BSWAP(A),BSWAP(B)) to BSWAP(BITWISE_OP(A, B))
/// \param I Binary operator to transform.
/// \return Pointer to node that must replace the original binary operator, or
/// null pointer if no transformation was made.
Value *InstCombiner::SimplifyBSwap(BinaryOperator &I) {
IntegerType *ITy = dyn_cast<IntegerType>(I.getType());
// Can't do vectors.
if (I.getType()->isVectorTy()) return nullptr;
// Can only do bitwise ops.
unsigned Op = I.getOpcode();
if (Op != Instruction::And && Op != Instruction::Or &&
Op != Instruction::Xor)
return nullptr;
Value *OldLHS = I.getOperand(0);
Value *OldRHS = I.getOperand(1);
ConstantInt *ConstLHS = dyn_cast<ConstantInt>(OldLHS);
ConstantInt *ConstRHS = dyn_cast<ConstantInt>(OldRHS);
IntrinsicInst *IntrLHS = dyn_cast<IntrinsicInst>(OldLHS);
IntrinsicInst *IntrRHS = dyn_cast<IntrinsicInst>(OldRHS);
bool IsBswapLHS = (IntrLHS && IntrLHS->getIntrinsicID() == Intrinsic::bswap);
bool IsBswapRHS = (IntrRHS && IntrRHS->getIntrinsicID() == Intrinsic::bswap);
if (!IsBswapLHS && !IsBswapRHS)
return nullptr;
if (!IsBswapLHS && !ConstLHS)
return nullptr;
if (!IsBswapRHS && !ConstRHS)
return nullptr;
/// OP( BSWAP(x), BSWAP(y) ) -> BSWAP( OP(x, y) )
/// OP( BSWAP(x), CONSTANT ) -> BSWAP( OP(x, BSWAP(CONSTANT) ) )
Value *NewLHS = IsBswapLHS ? IntrLHS->getOperand(0) :
Builder->getInt(ConstLHS->getValue().byteSwap());
Value *NewRHS = IsBswapRHS ? IntrRHS->getOperand(0) :
Builder->getInt(ConstRHS->getValue().byteSwap());
Value *BinOp = nullptr;
if (Op == Instruction::And)
BinOp = Builder->CreateAnd(NewLHS, NewRHS);
else if (Op == Instruction::Or)
BinOp = Builder->CreateOr(NewLHS, NewRHS);
else //if (Op == Instruction::Xor)
BinOp = Builder->CreateXor(NewLHS, NewRHS);
Module *M = I.getParent()->getParent()->getParent();
Function *F = Intrinsic::getDeclaration(M, Intrinsic::bswap, ITy);
return Builder->CreateCall(F, BinOp);
}
// OptAndOp - This handles expressions of the form ((val OP C1) & C2). Where
// the Op parameter is 'OP', OpRHS is 'C1', and AndRHS is 'C2'. Op is
// guaranteed to be a binary operator.
Instruction *InstCombiner::OptAndOp(Instruction *Op,
ConstantInt *OpRHS,
ConstantInt *AndRHS,
BinaryOperator &TheAnd) {
Value *X = Op->getOperand(0);
Constant *Together = nullptr;
if (!Op->isShift())
Together = ConstantExpr::getAnd(AndRHS, OpRHS);
switch (Op->getOpcode()) {
case Instruction::Xor:
if (Op->hasOneUse()) {
// (X ^ C1) & C2 --> (X & C2) ^ (C1&C2)
Value *And = Builder->CreateAnd(X, AndRHS);
And->takeName(Op);
return BinaryOperator::CreateXor(And, Together);
}
break;
case Instruction::Or:
if (Op->hasOneUse()){
if (Together != OpRHS) {
// (X | C1) & C2 --> (X | (C1&C2)) & C2
Value *Or = Builder->CreateOr(X, Together);
Or->takeName(Op);
return BinaryOperator::CreateAnd(Or, AndRHS);
}
ConstantInt *TogetherCI = dyn_cast<ConstantInt>(Together);
if (TogetherCI && !TogetherCI->isZero()){
// (X | C1) & C2 --> (X & (C2^(C1&C2))) | C1
// NOTE: This reduces the number of bits set in the & mask, which
// can expose opportunities for store narrowing.
Together = ConstantExpr::getXor(AndRHS, Together);
Value *And = Builder->CreateAnd(X, Together);
And->takeName(Op);
return BinaryOperator::CreateOr(And, OpRHS);
}
}
break;
case Instruction::Add:
if (Op->hasOneUse()) {
// Adding a one to a single bit bit-field should be turned into an XOR
// of the bit. First thing to check is to see if this AND is with a
// single bit constant.
const APInt &AndRHSV = AndRHS->getValue();
// If there is only one bit set.
if (AndRHSV.isPowerOf2()) {
// Ok, at this point, we know that we are masking the result of the
// ADD down to exactly one bit. If the constant we are adding has
// no bits set below this bit, then we can eliminate the ADD.
const APInt& AddRHS = OpRHS->getValue();
// Check to see if any bits below the one bit set in AndRHSV are set.
if ((AddRHS & (AndRHSV-1)) == 0) {
// If not, the only thing that can effect the output of the AND is
// the bit specified by AndRHSV. If that bit is set, the effect of
// the XOR is to toggle the bit. If it is clear, then the ADD has
// no effect.
if ((AddRHS & AndRHSV) == 0) { // Bit is not set, noop
TheAnd.setOperand(0, X);
return &TheAnd;
} else {
// Pull the XOR out of the AND.
Value *NewAnd = Builder->CreateAnd(X, AndRHS);
NewAnd->takeName(Op);
return BinaryOperator::CreateXor(NewAnd, AndRHS);
}
}
}
}
break;
case Instruction::Shl: {
// We know that the AND will not produce any of the bits shifted in, so if
// the anded constant includes them, clear them now!
//
uint32_t BitWidth = AndRHS->getType()->getBitWidth();
uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
APInt ShlMask(APInt::getHighBitsSet(BitWidth, BitWidth-OpRHSVal));
ConstantInt *CI = Builder->getInt(AndRHS->getValue() & ShlMask);
if (CI->getValue() == ShlMask)
// Masking out bits that the shift already masks.
return ReplaceInstUsesWith(TheAnd, Op); // No need for the and.
if (CI != AndRHS) { // Reducing bits set in and.
TheAnd.setOperand(1, CI);
return &TheAnd;
}
break;
}
case Instruction::LShr: {
// We know that the AND will not produce any of the bits shifted in, so if
// the anded constant includes them, clear them now! This only applies to
// unsigned shifts, because a signed shr may bring in set bits!
//
uint32_t BitWidth = AndRHS->getType()->getBitWidth();
uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
APInt ShrMask(APInt::getLowBitsSet(BitWidth, BitWidth - OpRHSVal));
ConstantInt *CI = Builder->getInt(AndRHS->getValue() & ShrMask);
if (CI->getValue() == ShrMask)
// Masking out bits that the shift already masks.
return ReplaceInstUsesWith(TheAnd, Op);
if (CI != AndRHS) {
TheAnd.setOperand(1, CI); // Reduce bits set in and cst.
return &TheAnd;
}
break;
}
case Instruction::AShr:
// Signed shr.
// See if this is shifting in some sign extension, then masking it out
// with an and.
if (Op->hasOneUse()) {
uint32_t BitWidth = AndRHS->getType()->getBitWidth();
uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
APInt ShrMask(APInt::getLowBitsSet(BitWidth, BitWidth - OpRHSVal));
Constant *C = Builder->getInt(AndRHS->getValue() & ShrMask);
if (C == AndRHS) { // Masking out bits shifted in.
// (Val ashr C1) & C2 -> (Val lshr C1) & C2
// Make the argument unsigned.
Value *ShVal = Op->getOperand(0);
ShVal = Builder->CreateLShr(ShVal, OpRHS, Op->getName());
return BinaryOperator::CreateAnd(ShVal, AndRHS, TheAnd.getName());
}
}
break;
}
return nullptr;
}
/// Emit a computation of: (V >= Lo && V < Hi) if Inside is true, otherwise
/// (V < Lo || V >= Hi). In practice, we emit the more efficient
/// (V-Lo) \<u Hi-Lo. This method expects that Lo <= Hi. isSigned indicates
/// whether to treat the V, Lo and HI as signed or not. IB is the location to
/// insert new instructions.
Value *InstCombiner::InsertRangeTest(Value *V, Constant *Lo, Constant *Hi,
bool isSigned, bool Inside) {
assert(cast<ConstantInt>(ConstantExpr::getICmp((isSigned ?
ICmpInst::ICMP_SLE:ICmpInst::ICMP_ULE), Lo, Hi))->getZExtValue() &&
"Lo is not <= Hi in range emission code!");
if (Inside) {
if (Lo == Hi) // Trivially false.
return Builder->getFalse();
// V >= Min && V < Hi --> V < Hi
if (cast<ConstantInt>(Lo)->isMinValue(isSigned)) {
ICmpInst::Predicate pred = (isSigned ?
ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT);
return Builder->CreateICmp(pred, V, Hi);
}
// Emit V-Lo <u Hi-Lo
Constant *NegLo = ConstantExpr::getNeg(Lo);
Value *Add = Builder->CreateAdd(V, NegLo, V->getName()+".off");
Constant *UpperBound = ConstantExpr::getAdd(NegLo, Hi);
return Builder->CreateICmpULT(Add, UpperBound);
}
if (Lo == Hi) // Trivially true.
return Builder->getTrue();
// V < Min || V >= Hi -> V > Hi-1
Hi = SubOne(cast<ConstantInt>(Hi));
if (cast<ConstantInt>(Lo)->isMinValue(isSigned)) {
ICmpInst::Predicate pred = (isSigned ?
ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT);
return Builder->CreateICmp(pred, V, Hi);
}
// Emit V-Lo >u Hi-1-Lo
// Note that Hi has already had one subtracted from it, above.
ConstantInt *NegLo = cast<ConstantInt>(ConstantExpr::getNeg(Lo));
Value *Add = Builder->CreateAdd(V, NegLo, V->getName()+".off");
Constant *LowerBound = ConstantExpr::getAdd(NegLo, Hi);
return Builder->CreateICmpUGT(Add, LowerBound);
}
// isRunOfOnes - Returns true iff Val consists of one contiguous run of 1s with
// any number of 0s on either side. The 1s are allowed to wrap from LSB to
// MSB, so 0x000FFF0, 0x0000FFFF, and 0xFF0000FF are all runs. 0x0F0F0000 is
// not, since all 1s are not contiguous.
static bool isRunOfOnes(ConstantInt *Val, uint32_t &MB, uint32_t &ME) {
const APInt& V = Val->getValue();
uint32_t BitWidth = Val->getType()->getBitWidth();
if (!APIntOps::isShiftedMask(BitWidth, V)) return false;
// look for the first zero bit after the run of ones
MB = BitWidth - ((V - 1) ^ V).countLeadingZeros();
// look for the first non-zero bit
ME = V.getActiveBits();
return true;
}
/// FoldLogicalPlusAnd - This is part of an expression (LHS +/- RHS) & Mask,
/// where isSub determines whether the operator is a sub. If we can fold one of
/// the following xforms:
///
/// ((A & N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == Mask
/// ((A | N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == 0
/// ((A ^ N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == 0
///
/// return (A +/- B).
///
Value *InstCombiner::FoldLogicalPlusAnd(Value *LHS, Value *RHS,
ConstantInt *Mask, bool isSub,
Instruction &I) {
Instruction *LHSI = dyn_cast<Instruction>(LHS);
if (!LHSI || LHSI->getNumOperands() != 2 ||
!isa<ConstantInt>(LHSI->getOperand(1))) return nullptr;
ConstantInt *N = cast<ConstantInt>(LHSI->getOperand(1));
switch (LHSI->getOpcode()) {
default: return nullptr;
case Instruction::And:
if (ConstantExpr::getAnd(N, Mask) == Mask) {
// If the AndRHS is a power of two minus one (0+1+), this is simple.
if ((Mask->getValue().countLeadingZeros() +
Mask->getValue().countPopulation()) ==
Mask->getValue().getBitWidth())
break;
// Otherwise, if Mask is 0+1+0+, and if B is known to have the low 0+
// part, we don't need any explicit masks to take them out of A. If that
// is all N is, ignore it.
uint32_t MB = 0, ME = 0;
if (isRunOfOnes(Mask, MB, ME)) { // begin/end bit of run, inclusive
uint32_t BitWidth = cast<IntegerType>(RHS->getType())->getBitWidth();
APInt Mask(APInt::getLowBitsSet(BitWidth, MB-1));
if (MaskedValueIsZero(RHS, Mask, 0, &I))
break;
}
}
return nullptr;
case Instruction::Or:
case Instruction::Xor:
// If the AndRHS is a power of two minus one (0+1+), and N&Mask == 0
if ((Mask->getValue().countLeadingZeros() +
Mask->getValue().countPopulation()) == Mask->getValue().getBitWidth()
&& ConstantExpr::getAnd(N, Mask)->isNullValue())
break;
return nullptr;
}
if (isSub)
return Builder->CreateSub(LHSI->getOperand(0), RHS, "fold");
return Builder->CreateAdd(LHSI->getOperand(0), RHS, "fold");
}
/// enum for classifying (icmp eq (A & B), C) and (icmp ne (A & B), C)
/// One of A and B is considered the mask, the other the value. This is
/// described as the "AMask" or "BMask" part of the enum. If the enum
/// contains only "Mask", then both A and B can be considered masks.
/// If A is the mask, then it was proven, that (A & C) == C. This
/// is trivial if C == A, or C == 0. If both A and C are constants, this
/// proof is also easy.
/// For the following explanations we assume that A is the mask.
/// The part "AllOnes" declares, that the comparison is true only
/// if (A & B) == A, or all bits of A are set in B.
/// Example: (icmp eq (A & 3), 3) -> FoldMskICmp_AMask_AllOnes
/// The part "AllZeroes" declares, that the comparison is true only
/// if (A & B) == 0, or all bits of A are cleared in B.
/// Example: (icmp eq (A & 3), 0) -> FoldMskICmp_Mask_AllZeroes
/// The part "Mixed" declares, that (A & B) == C and C might or might not
/// contain any number of one bits and zero bits.
/// Example: (icmp eq (A & 3), 1) -> FoldMskICmp_AMask_Mixed
/// The Part "Not" means, that in above descriptions "==" should be replaced
/// by "!=".
/// Example: (icmp ne (A & 3), 3) -> FoldMskICmp_AMask_NotAllOnes
/// If the mask A contains a single bit, then the following is equivalent:
/// (icmp eq (A & B), A) equals (icmp ne (A & B), 0)
/// (icmp ne (A & B), A) equals (icmp eq (A & B), 0)
enum MaskedICmpType {
FoldMskICmp_AMask_AllOnes = 1,
FoldMskICmp_AMask_NotAllOnes = 2,
FoldMskICmp_BMask_AllOnes = 4,
FoldMskICmp_BMask_NotAllOnes = 8,
FoldMskICmp_Mask_AllZeroes = 16,
FoldMskICmp_Mask_NotAllZeroes = 32,
FoldMskICmp_AMask_Mixed = 64,
FoldMskICmp_AMask_NotMixed = 128,
FoldMskICmp_BMask_Mixed = 256,
FoldMskICmp_BMask_NotMixed = 512
};
/// return the set of pattern classes (from MaskedICmpType)
/// that (icmp SCC (A & B), C) satisfies
static unsigned getTypeOfMaskedICmp(Value* A, Value* B, Value* C,
ICmpInst::Predicate SCC)
{
ConstantInt *ACst = dyn_cast<ConstantInt>(A);
ConstantInt *BCst = dyn_cast<ConstantInt>(B);
ConstantInt *CCst = dyn_cast<ConstantInt>(C);
bool icmp_eq = (SCC == ICmpInst::ICMP_EQ);
bool icmp_abit = (ACst && !ACst->isZero() &&
ACst->getValue().isPowerOf2());
bool icmp_bbit = (BCst && !BCst->isZero() &&
BCst->getValue().isPowerOf2());
unsigned result = 0;
if (CCst && CCst->isZero()) {
// if C is zero, then both A and B qualify as mask
result |= (icmp_eq ? (FoldMskICmp_Mask_AllZeroes |
FoldMskICmp_Mask_AllZeroes |
FoldMskICmp_AMask_Mixed |
FoldMskICmp_BMask_Mixed)
: (FoldMskICmp_Mask_NotAllZeroes |
FoldMskICmp_Mask_NotAllZeroes |
FoldMskICmp_AMask_NotMixed |
FoldMskICmp_BMask_NotMixed));
if (icmp_abit)
result |= (icmp_eq ? (FoldMskICmp_AMask_NotAllOnes |
FoldMskICmp_AMask_NotMixed)
: (FoldMskICmp_AMask_AllOnes |
FoldMskICmp_AMask_Mixed));
if (icmp_bbit)
result |= (icmp_eq ? (FoldMskICmp_BMask_NotAllOnes |
FoldMskICmp_BMask_NotMixed)
: (FoldMskICmp_BMask_AllOnes |
FoldMskICmp_BMask_Mixed));
return result;
}
if (A == C) {
result |= (icmp_eq ? (FoldMskICmp_AMask_AllOnes |
FoldMskICmp_AMask_Mixed)
: (FoldMskICmp_AMask_NotAllOnes |
FoldMskICmp_AMask_NotMixed));
if (icmp_abit)
result |= (icmp_eq ? (FoldMskICmp_Mask_NotAllZeroes |
FoldMskICmp_AMask_NotMixed)
: (FoldMskICmp_Mask_AllZeroes |
FoldMskICmp_AMask_Mixed));
} else if (ACst && CCst &&
ConstantExpr::getAnd(ACst, CCst) == CCst) {
result |= (icmp_eq ? FoldMskICmp_AMask_Mixed
: FoldMskICmp_AMask_NotMixed);
}
if (B == C) {
result |= (icmp_eq ? (FoldMskICmp_BMask_AllOnes |
FoldMskICmp_BMask_Mixed)
: (FoldMskICmp_BMask_NotAllOnes |
FoldMskICmp_BMask_NotMixed));
if (icmp_bbit)
result |= (icmp_eq ? (FoldMskICmp_Mask_NotAllZeroes |
FoldMskICmp_BMask_NotMixed)
: (FoldMskICmp_Mask_AllZeroes |
FoldMskICmp_BMask_Mixed));
} else if (BCst && CCst &&
ConstantExpr::getAnd(BCst, CCst) == CCst) {
result |= (icmp_eq ? FoldMskICmp_BMask_Mixed
: FoldMskICmp_BMask_NotMixed);
}
return result;
}
/// Convert an analysis of a masked ICmp into its equivalent if all boolean
/// operations had the opposite sense. Since each "NotXXX" flag (recording !=)
/// is adjacent to the corresponding normal flag (recording ==), this just
/// involves swapping those bits over.
static unsigned conjugateICmpMask(unsigned Mask) {
unsigned NewMask;
NewMask = (Mask & (FoldMskICmp_AMask_AllOnes | FoldMskICmp_BMask_AllOnes |
FoldMskICmp_Mask_AllZeroes | FoldMskICmp_AMask_Mixed |
FoldMskICmp_BMask_Mixed))
<< 1;
NewMask |=
(Mask & (FoldMskICmp_AMask_NotAllOnes | FoldMskICmp_BMask_NotAllOnes |
FoldMskICmp_Mask_NotAllZeroes | FoldMskICmp_AMask_NotMixed |
FoldMskICmp_BMask_NotMixed))
>> 1;
return NewMask;
}
/// decomposeBitTestICmp - Decompose an icmp into the form ((X & Y) pred Z)
/// if possible. The returned predicate is either == or !=. Returns false if
/// decomposition fails.
static bool decomposeBitTestICmp(const ICmpInst *I, ICmpInst::Predicate &Pred,
Value *&X, Value *&Y, Value *&Z) {
ConstantInt *C = dyn_cast<ConstantInt>(I->getOperand(1));
if (!C)
return false;
switch (I->getPredicate()) {
default:
return false;
case ICmpInst::ICMP_SLT:
// X < 0 is equivalent to (X & SignBit) != 0.
if (!C->isZero())
return false;
Y = ConstantInt::get(I->getContext(), APInt::getSignBit(C->getBitWidth()));
Pred = ICmpInst::ICMP_NE;
break;
case ICmpInst::ICMP_SGT:
// X > -1 is equivalent to (X & SignBit) == 0.
if (!C->isAllOnesValue())
return false;
Y = ConstantInt::get(I->getContext(), APInt::getSignBit(C->getBitWidth()));
Pred = ICmpInst::ICMP_EQ;
break;
case ICmpInst::ICMP_ULT:
// X <u 2^n is equivalent to (X & ~(2^n-1)) == 0.
if (!C->getValue().isPowerOf2())
return false;
Y = ConstantInt::get(I->getContext(), -C->getValue());
Pred = ICmpInst::ICMP_EQ;
break;
case ICmpInst::ICMP_UGT:
// X >u 2^n-1 is equivalent to (X & ~(2^n-1)) != 0.
if (!(C->getValue() + 1).isPowerOf2())
return false;
Y = ConstantInt::get(I->getContext(), ~C->getValue());
Pred = ICmpInst::ICMP_NE;
break;
}
X = I->getOperand(0);
Z = ConstantInt::getNullValue(C->getType());
return true;
}
/// foldLogOpOfMaskedICmpsHelper:
/// handle (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E)
/// return the set of pattern classes (from MaskedICmpType)
/// that both LHS and RHS satisfy
static unsigned foldLogOpOfMaskedICmpsHelper(Value*& A,
Value*& B, Value*& C,
Value*& D, Value*& E,
ICmpInst *LHS, ICmpInst *RHS,
ICmpInst::Predicate &LHSCC,
ICmpInst::Predicate &RHSCC) {
if (LHS->getOperand(0)->getType() != RHS->getOperand(0)->getType()) return 0;
// vectors are not (yet?) supported
if (LHS->getOperand(0)->getType()->isVectorTy()) return 0;
// Here comes the tricky part:
// LHS might be of the form L11 & L12 == X, X == L21 & L22,
// and L11 & L12 == L21 & L22. The same goes for RHS.
// Now we must find those components L** and R**, that are equal, so
// that we can extract the parameters A, B, C, D, and E for the canonical
// above.
Value *L1 = LHS->getOperand(0);
Value *L2 = LHS->getOperand(1);
Value *L11,*L12,*L21,*L22;
// Check whether the icmp can be decomposed into a bit test.
if (decomposeBitTestICmp(LHS, LHSCC, L11, L12, L2)) {
L21 = L22 = L1 = nullptr;
} else {
// Look for ANDs in the LHS icmp.
if (!L1->getType()->isIntegerTy()) {
// You can icmp pointers, for example. They really aren't masks.
L11 = L12 = nullptr;
} else if (!match(L1, m_And(m_Value(L11), m_Value(L12)))) {
// Any icmp can be viewed as being trivially masked; if it allows us to
// remove one, it's worth it.
L11 = L1;
L12 = Constant::getAllOnesValue(L1->getType());
}
if (!L2->getType()->isIntegerTy()) {
// You can icmp pointers, for example. They really aren't masks.
L21 = L22 = nullptr;
} else if (!match(L2, m_And(m_Value(L21), m_Value(L22)))) {
L21 = L2;
L22 = Constant::getAllOnesValue(L2->getType());
}
}
// Bail if LHS was a icmp that can't be decomposed into an equality.
if (!ICmpInst::isEquality(LHSCC))
return 0;
Value *R1 = RHS->getOperand(0);
Value *R2 = RHS->getOperand(1);
Value *R11,*R12;
bool ok = false;
if (decomposeBitTestICmp(RHS, RHSCC, R11, R12, R2)) {
if (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22) {
A = R11; D = R12;
} else if (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22) {
A = R12; D = R11;
} else {
return 0;
}
E = R2; R1 = nullptr; ok = true;
} else if (R1->getType()->isIntegerTy()) {
if (!match(R1, m_And(m_Value(R11), m_Value(R12)))) {
// As before, model no mask as a trivial mask if it'll let us do an
// optimization.
R11 = R1;
R12 = Constant::getAllOnesValue(R1->getType());
}
if (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22) {
A = R11; D = R12; E = R2; ok = true;
} else if (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22) {
A = R12; D = R11; E = R2; ok = true;
}
}
// Bail if RHS was a icmp that can't be decomposed into an equality.
if (!ICmpInst::isEquality(RHSCC))
return 0;
// Look for ANDs in on the right side of the RHS icmp.
if (!ok && R2->getType()->isIntegerTy()) {
if (!match(R2, m_And(m_Value(R11), m_Value(R12)))) {
R11 = R2;
R12 = Constant::getAllOnesValue(R2->getType());
}
if (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22) {
A = R11; D = R12; E = R1; ok = true;
} else if (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22) {
A = R12; D = R11; E = R1; ok = true;
} else {
return 0;
}
}
if (!ok)
return 0;
if (L11 == A) {
B = L12; C = L2;
} else if (L12 == A) {
B = L11; C = L2;
} else if (L21 == A) {
B = L22; C = L1;
} else if (L22 == A) {
B = L21; C = L1;
}
unsigned left_type = getTypeOfMaskedICmp(A, B, C, LHSCC);
unsigned right_type = getTypeOfMaskedICmp(A, D, E, RHSCC);
return left_type & right_type;
}
/// foldLogOpOfMaskedICmps:
/// try to fold (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E)
/// into a single (icmp(A & X) ==/!= Y)
static Value *foldLogOpOfMaskedICmps(ICmpInst *LHS, ICmpInst *RHS, bool IsAnd,
llvm::InstCombiner::BuilderTy *Builder) {
Value *A = nullptr, *B = nullptr, *C = nullptr, *D = nullptr, *E = nullptr;
ICmpInst::Predicate LHSCC = LHS->getPredicate(), RHSCC = RHS->getPredicate();
unsigned mask = foldLogOpOfMaskedICmpsHelper(A, B, C, D, E, LHS, RHS,
LHSCC, RHSCC);
if (mask == 0) return nullptr;
assert(ICmpInst::isEquality(LHSCC) && ICmpInst::isEquality(RHSCC) &&
"foldLogOpOfMaskedICmpsHelper must return an equality predicate.");
// In full generality:
// (icmp (A & B) Op C) | (icmp (A & D) Op E)
// == ![ (icmp (A & B) !Op C) & (icmp (A & D) !Op E) ]
//
// If the latter can be converted into (icmp (A & X) Op Y) then the former is
// equivalent to (icmp (A & X) !Op Y).
//
// Therefore, we can pretend for the rest of this function that we're dealing
// with the conjunction, provided we flip the sense of any comparisons (both
// input and output).
// In most cases we're going to produce an EQ for the "&&" case.
ICmpInst::Predicate NEWCC = IsAnd ? ICmpInst::ICMP_EQ : ICmpInst::ICMP_NE;
if (!IsAnd) {
// Convert the masking analysis into its equivalent with negated
// comparisons.
mask = conjugateICmpMask(mask);
}
if (mask & FoldMskICmp_Mask_AllZeroes) {
// (icmp eq (A & B), 0) & (icmp eq (A & D), 0)
// -> (icmp eq (A & (B|D)), 0)
Value *newOr = Builder->CreateOr(B, D);
Value *newAnd = Builder->CreateAnd(A, newOr);
// we can't use C as zero, because we might actually handle
// (icmp ne (A & B), B) & (icmp ne (A & D), D)
// with B and D, having a single bit set
Value *zero = Constant::getNullValue(A->getType());
return Builder->CreateICmp(NEWCC, newAnd, zero);
}
if (mask & FoldMskICmp_BMask_AllOnes) {
// (icmp eq (A & B), B) & (icmp eq (A & D), D)
// -> (icmp eq (A & (B|D)), (B|D))
Value *newOr = Builder->CreateOr(B, D);
Value *newAnd = Builder->CreateAnd(A, newOr);
return Builder->CreateICmp(NEWCC, newAnd, newOr);
}
if (mask & FoldMskICmp_AMask_AllOnes) {
// (icmp eq (A & B), A) & (icmp eq (A & D), A)
// -> (icmp eq (A & (B&D)), A)
Value *newAnd1 = Builder->CreateAnd(B, D);
Value *newAnd = Builder->CreateAnd(A, newAnd1);
return Builder->CreateICmp(NEWCC, newAnd, A);
}
// Remaining cases assume at least that B and D are constant, and depend on
// their actual values. This isn't strictly, necessary, just a "handle the
// easy cases for now" decision.
ConstantInt *BCst = dyn_cast<ConstantInt>(B);
if (!BCst) return nullptr;
ConstantInt *DCst = dyn_cast<ConstantInt>(D);
if (!DCst) return nullptr;
if (mask & (FoldMskICmp_Mask_NotAllZeroes | FoldMskICmp_BMask_NotAllOnes)) {
// (icmp ne (A & B), 0) & (icmp ne (A & D), 0) and
// (icmp ne (A & B), B) & (icmp ne (A & D), D)
// -> (icmp ne (A & B), 0) or (icmp ne (A & D), 0)
// Only valid if one of the masks is a superset of the other (check "B&D" is
// the same as either B or D).
APInt NewMask = BCst->getValue() & DCst->getValue();
if (NewMask == BCst->getValue())
return LHS;
else if (NewMask == DCst->getValue())
return RHS;
}
if (mask & FoldMskICmp_AMask_NotAllOnes) {
// (icmp ne (A & B), B) & (icmp ne (A & D), D)
// -> (icmp ne (A & B), A) or (icmp ne (A & D), A)
// Only valid if one of the masks is a superset of the other (check "B|D" is
// the same as either B or D).
APInt NewMask = BCst->getValue() | DCst->getValue();
if (NewMask == BCst->getValue())
return LHS;
else if (NewMask == DCst->getValue())
return RHS;
}
if (mask & FoldMskICmp_BMask_Mixed) {
// (icmp eq (A & B), C) & (icmp eq (A & D), E)
// We already know that B & C == C && D & E == E.
// If we can prove that (B & D) & (C ^ E) == 0, that is, the bits of
// C and E, which are shared by both the mask B and the mask D, don't
// contradict, then we can transform to
// -> (icmp eq (A & (B|D)), (C|E))
// Currently, we only handle the case of B, C, D, and E being constant.
// we can't simply use C and E, because we might actually handle
// (icmp ne (A & B), B) & (icmp eq (A & D), D)
// with B and D, having a single bit set
ConstantInt *CCst = dyn_cast<ConstantInt>(C);
if (!CCst) return nullptr;
ConstantInt *ECst = dyn_cast<ConstantInt>(E);
if (!ECst) return nullptr;
if (LHSCC != NEWCC)
CCst = cast<ConstantInt>(ConstantExpr::getXor(BCst, CCst));
if (RHSCC != NEWCC)
ECst = cast<ConstantInt>(ConstantExpr::getXor(DCst, ECst));
// if there is a conflict we should actually return a false for the
// whole construct
if (((BCst->getValue() & DCst->getValue()) &
(CCst->getValue() ^ ECst->getValue())) != 0)
return ConstantInt::get(LHS->getType(), !IsAnd);
Value *newOr1 = Builder->CreateOr(B, D);
Value *newOr2 = ConstantExpr::getOr(CCst, ECst);
Value *newAnd = Builder->CreateAnd(A, newOr1);
return Builder->CreateICmp(NEWCC, newAnd, newOr2);
}
return nullptr;
}
/// Try to fold a signed range checked with lower bound 0 to an unsigned icmp.
/// Example: (icmp sge x, 0) & (icmp slt x, n) --> icmp ult x, n
/// If \p Inverted is true then the check is for the inverted range, e.g.
/// (icmp slt x, 0) | (icmp sgt x, n) --> icmp ugt x, n
Value *InstCombiner::simplifyRangeCheck(ICmpInst *Cmp0, ICmpInst *Cmp1,
bool Inverted) {
// Check the lower range comparison, e.g. x >= 0
// InstCombine already ensured that if there is a constant it's on the RHS.
ConstantInt *RangeStart = dyn_cast<ConstantInt>(Cmp0->getOperand(1));
if (!RangeStart)
return nullptr;
ICmpInst::Predicate Pred0 = (Inverted ? Cmp0->getInversePredicate() :
Cmp0->getPredicate());
// Accept x > -1 or x >= 0 (after potentially inverting the predicate).
if (!((Pred0 == ICmpInst::ICMP_SGT && RangeStart->isMinusOne()) ||
(Pred0 == ICmpInst::ICMP_SGE && RangeStart->isZero())))
return nullptr;
ICmpInst::Predicate Pred1 = (Inverted ? Cmp1->getInversePredicate() :
Cmp1->getPredicate());
Value *Input = Cmp0->getOperand(0);
Value *RangeEnd;
if (Cmp1->getOperand(0) == Input) {
// For the upper range compare we have: icmp x, n
RangeEnd = Cmp1->getOperand(1);
} else if (Cmp1->getOperand(1) == Input) {
// For the upper range compare we have: icmp n, x
RangeEnd = Cmp1->getOperand(0);
Pred1 = ICmpInst::getSwappedPredicate(Pred1);
} else {
return nullptr;
}
// Check the upper range comparison, e.g. x < n
ICmpInst::Predicate NewPred;
switch (Pred1) {
case ICmpInst::ICMP_SLT: NewPred = ICmpInst::ICMP_ULT; break;
case ICmpInst::ICMP_SLE: NewPred = ICmpInst::ICMP_ULE; break;
default: return nullptr;
}
// This simplification is only valid if the upper range is not negative.
bool IsNegative, IsNotNegative;
ComputeSignBit(RangeEnd, IsNotNegative, IsNegative, /*Depth=*/0, Cmp1);
if (!IsNotNegative)
return nullptr;
if (Inverted)
NewPred = ICmpInst::getInversePredicate(NewPred);
return Builder->CreateICmp(NewPred, Input, RangeEnd);
}
/// FoldAndOfICmps - Fold (icmp)&(icmp) if possible.
Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
ICmpInst::Predicate LHSCC = LHS->getPredicate(), RHSCC = RHS->getPredicate();
// (icmp1 A, B) & (icmp2 A, B) --> (icmp3 A, B)
if (PredicatesFoldable(LHSCC, RHSCC)) {
if (LHS->getOperand(0) == RHS->getOperand(1) &&
LHS->getOperand(1) == RHS->getOperand(0))
LHS->swapOperands();
if (LHS->getOperand(0) == RHS->getOperand(0) &&
LHS->getOperand(1) == RHS->getOperand(1)) {
Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
unsigned Code = getICmpCode(LHS) & getICmpCode(RHS);
bool isSigned = LHS->isSigned() || RHS->isSigned();
return getNewICmpValue(isSigned, Code, Op0, Op1, Builder);
}
}
// handle (roughly): (icmp eq (A & B), C) & (icmp eq (A & D), E)
if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, true, Builder))
return V;
// E.g. (icmp sge x, 0) & (icmp slt x, n) --> icmp ult x, n
if (Value *V = simplifyRangeCheck(LHS, RHS, /*Inverted=*/false))
return V;
// E.g. (icmp slt x, n) & (icmp sge x, 0) --> icmp ult x, n
if (Value *V = simplifyRangeCheck(RHS, LHS, /*Inverted=*/false))
return V;
// This only handles icmp of constants: (icmp1 A, C1) & (icmp2 B, C2).
Value *Val = LHS->getOperand(0), *Val2 = RHS->getOperand(0);
ConstantInt *LHSCst = dyn_cast<ConstantInt>(LHS->getOperand(1));
ConstantInt *RHSCst = dyn_cast<ConstantInt>(RHS->getOperand(1));
if (!LHSCst || !RHSCst) return nullptr;
if (LHSCst == RHSCst && LHSCC == RHSCC) {
// (icmp ult A, C) & (icmp ult B, C) --> (icmp ult (A|B), C)
// where C is a power of 2
if (LHSCC == ICmpInst::ICMP_ULT &&
LHSCst->getValue().isPowerOf2()) {
Value *NewOr = Builder->CreateOr(Val, Val2);
return Builder->CreateICmp(LHSCC, NewOr, LHSCst);
}
// (icmp eq A, 0) & (icmp eq B, 0) --> (icmp eq (A|B), 0)
if (LHSCC == ICmpInst::ICMP_EQ && LHSCst->isZero()) {
Value *NewOr = Builder->CreateOr(Val, Val2);
return Builder->CreateICmp(LHSCC, NewOr, LHSCst);
}
}
// (trunc x) == C1 & (and x, CA) == C2 -> (and x, CA|CMAX) == C1|C2
// where CMAX is the all ones value for the truncated type,
// iff the lower bits of C2 and CA are zero.
if (LHSCC == ICmpInst::ICMP_EQ && LHSCC == RHSCC &&
LHS->hasOneUse() && RHS->hasOneUse()) {
Value *V;
ConstantInt *AndCst, *SmallCst = nullptr, *BigCst = nullptr;
// (trunc x) == C1 & (and x, CA) == C2
// (and x, CA) == C2 & (trunc x) == C1
if (match(Val2, m_Trunc(m_Value(V))) &&
match(Val, m_And(m_Specific(V), m_ConstantInt(AndCst)))) {
SmallCst = RHSCst;
BigCst = LHSCst;
} else if (match(Val, m_Trunc(m_Value(V))) &&
match(Val2, m_And(m_Specific(V), m_ConstantInt(AndCst)))) {
SmallCst = LHSCst;
BigCst = RHSCst;
}
if (SmallCst && BigCst) {
unsigned BigBitSize = BigCst->getType()->getBitWidth();
unsigned SmallBitSize = SmallCst->getType()->getBitWidth();
// Check that the low bits are zero.
APInt Low = APInt::getLowBitsSet(BigBitSize, SmallBitSize);
if ((Low & AndCst->getValue()) == 0 && (Low & BigCst->getValue()) == 0) {
Value *NewAnd = Builder->CreateAnd(V, Low | AndCst->getValue());
APInt N = SmallCst->getValue().zext(BigBitSize) | BigCst->getValue();
Value *NewVal = ConstantInt::get(AndCst->getType()->getContext(), N);
return Builder->CreateICmp(LHSCC, NewAnd, NewVal);
}
}
}
// From here on, we only handle:
// (icmp1 A, C1) & (icmp2 A, C2) --> something simpler.
if (Val != Val2) return nullptr;
// ICMP_[US][GL]E X, CST is folded to ICMP_[US][GL]T elsewhere.
if (LHSCC == ICmpInst::ICMP_UGE || LHSCC == ICmpInst::ICMP_ULE ||
RHSCC == ICmpInst::ICMP_UGE || RHSCC == ICmpInst::ICMP_ULE ||
LHSCC == ICmpInst::ICMP_SGE || LHSCC == ICmpInst::ICMP_SLE ||
RHSCC == ICmpInst::ICMP_SGE || RHSCC == ICmpInst::ICMP_SLE)
return nullptr;
// Make a constant range that's the intersection of the two icmp ranges.
// If the intersection is empty, we know that the result is false.
ConstantRange LHSRange =
ConstantRange::makeAllowedICmpRegion(LHSCC, LHSCst->getValue());
ConstantRange RHSRange =
ConstantRange::makeAllowedICmpRegion(RHSCC, RHSCst->getValue());
if (LHSRange.intersectWith(RHSRange).isEmptySet())
return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
// We can't fold (ugt x, C) & (sgt x, C2).
if (!PredicatesFoldable(LHSCC, RHSCC))
return nullptr;
// Ensure that the larger constant is on the RHS.
bool ShouldSwap;
if (CmpInst::isSigned(LHSCC) ||
(ICmpInst::isEquality(LHSCC) &&
CmpInst::isSigned(RHSCC)))
ShouldSwap = LHSCst->getValue().sgt(RHSCst->getValue());
else
ShouldSwap = LHSCst->getValue().ugt(RHSCst->getValue());
if (ShouldSwap) {
std::swap(LHS, RHS);
std::swap(LHSCst, RHSCst);
std::swap(LHSCC, RHSCC);
}
// At this point, we know we have two icmp instructions
// comparing a value against two constants and and'ing the result
// together. Because of the above check, we know that we only have
// icmp eq, icmp ne, icmp [su]lt, and icmp [SU]gt here. We also know
// (from the icmp folding check above), that the two constants
// are not equal and that the larger constant is on the RHS
assert(LHSCst != RHSCst && "Compares not folded above?");
switch (LHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
case ICmpInst::ICMP_EQ:
switch (RHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
case ICmpInst::ICMP_NE: // (X == 13 & X != 15) -> X == 13
case ICmpInst::ICMP_ULT: // (X == 13 & X < 15) -> X == 13
case ICmpInst::ICMP_SLT: // (X == 13 & X < 15) -> X == 13
return LHS;
}
case ICmpInst::ICMP_NE:
switch (RHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
case ICmpInst::ICMP_ULT:
if (LHSCst == SubOne(RHSCst)) // (X != 13 & X u< 14) -> X < 13
return Builder->CreateICmpULT(Val, LHSCst);
if (LHSCst->isNullValue()) // (X != 0 & X u< 14) -> X-1 u< 13
return InsertRangeTest(Val, AddOne(LHSCst), RHSCst, false, true);
break; // (X != 13 & X u< 15) -> no change
case ICmpInst::ICMP_SLT:
if (LHSCst == SubOne(RHSCst)) // (X != 13 & X s< 14) -> X < 13
return Builder->CreateICmpSLT(Val, LHSCst);
break; // (X != 13 & X s< 15) -> no change
case ICmpInst::ICMP_EQ: // (X != 13 & X == 15) -> X == 15
case ICmpInst::ICMP_UGT: // (X != 13 & X u> 15) -> X u> 15
case ICmpInst::ICMP_SGT: // (X != 13 & X s> 15) -> X s> 15
return RHS;
case ICmpInst::ICMP_NE:
// Special case to get the ordering right when the values wrap around
// zero.
if (LHSCst->getValue() == 0 && RHSCst->getValue().isAllOnesValue())
std::swap(LHSCst, RHSCst);
if (LHSCst == SubOne(RHSCst)){// (X != 13 & X != 14) -> X-13 >u 1
Constant *AddCST = ConstantExpr::getNeg(LHSCst);
Value *Add = Builder->CreateAdd(Val, AddCST, Val->getName()+".off");
return Builder->CreateICmpUGT(Add, ConstantInt::get(Add->getType(), 1),
Val->getName()+".cmp");
}
break; // (X != 13 & X != 15) -> no change
}
break;
case ICmpInst::ICMP_ULT:
switch (RHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
case ICmpInst::ICMP_EQ: // (X u< 13 & X == 15) -> false
case ICmpInst::ICMP_UGT: // (X u< 13 & X u> 15) -> false
return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
case ICmpInst::ICMP_SGT: // (X u< 13 & X s> 15) -> no change
break;
case ICmpInst::ICMP_NE: // (X u< 13 & X != 15) -> X u< 13
case ICmpInst::ICMP_ULT: // (X u< 13 & X u< 15) -> X u< 13
return LHS;
case ICmpInst::ICMP_SLT: // (X u< 13 & X s< 15) -> no change
break;
}
break;
case ICmpInst::ICMP_SLT:
switch (RHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
case ICmpInst::ICMP_UGT: // (X s< 13 & X u> 15) -> no change
break;
case ICmpInst::ICMP_NE: // (X s< 13 & X != 15) -> X < 13
case ICmpInst::ICMP_SLT: // (X s< 13 & X s< 15) -> X < 13
return LHS;
case ICmpInst::ICMP_ULT: // (X s< 13 & X u< 15) -> no change
break;
}
break;
case ICmpInst::ICMP_UGT:
switch (RHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
case ICmpInst::ICMP_EQ: // (X u> 13 & X == 15) -> X == 15
case ICmpInst::ICMP_UGT: // (X u> 13 & X u> 15) -> X u> 15
return RHS;
case ICmpInst::ICMP_SGT: // (X u> 13 & X s> 15) -> no change
break;
case ICmpInst::ICMP_NE:
if (RHSCst == AddOne(LHSCst)) // (X u> 13 & X != 14) -> X u> 14
return Builder->CreateICmp(LHSCC, Val, RHSCst);
break; // (X u> 13 & X != 15) -> no change
case ICmpInst::ICMP_ULT: // (X u> 13 & X u< 15) -> (X-14) <u 1
return InsertRangeTest(Val, AddOne(LHSCst), RHSCst, false, true);
case ICmpInst::ICMP_SLT: // (X u> 13 & X s< 15) -> no change
break;
}
break;
case ICmpInst::ICMP_SGT:
switch (RHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
case ICmpInst::ICMP_EQ: // (X s> 13 & X == 15) -> X == 15
case ICmpInst::ICMP_SGT: // (X s> 13 & X s> 15) -> X s> 15
return RHS;
case ICmpInst::ICMP_UGT: // (X s> 13 & X u> 15) -> no change
break;
case ICmpInst::ICMP_NE:
if (RHSCst == AddOne(LHSCst)) // (X s> 13 & X != 14) -> X s> 14
return Builder->CreateICmp(LHSCC, Val, RHSCst);
break; // (X s> 13 & X != 15) -> no change
case ICmpInst::ICMP_SLT: // (X s> 13 & X s< 15) -> (X-14) s< 1
return InsertRangeTest(Val, AddOne(LHSCst), RHSCst, true, true);
case ICmpInst::ICMP_ULT: // (X s> 13 & X u< 15) -> no change
break;
}
break;
}
return nullptr;
}
/// FoldAndOfFCmps - Optimize (fcmp)&(fcmp). NOTE: Unlike the rest of
/// instcombine, this returns a Value which should already be inserted into the
/// function.
Value *InstCombiner::FoldAndOfFCmps(FCmpInst *LHS, FCmpInst *RHS) {
if (LHS->getPredicate() == FCmpInst::FCMP_ORD &&
RHS->getPredicate() == FCmpInst::FCMP_ORD) {
if (LHS->getOperand(0)->getType() != RHS->getOperand(0)->getType())
return nullptr;
// (fcmp ord x, c) & (fcmp ord y, c) -> (fcmp ord x, y)
if (ConstantFP *LHSC = dyn_cast<ConstantFP>(LHS->getOperand(1)))
if (ConstantFP *RHSC = dyn_cast<ConstantFP>(RHS->getOperand(1))) {
// If either of the constants are nans, then the whole thing returns
// false.
if (LHSC->getValueAPF().isNaN() || RHSC->getValueAPF().isNaN())
return Builder->getFalse();
return Builder->CreateFCmpORD(LHS->getOperand(0), RHS->getOperand(0));
}
// Handle vector zeros. This occurs because the canonical form of
// "fcmp ord x,x" is "fcmp ord x, 0".
if (isa<ConstantAggregateZero>(LHS->getOperand(1)) &&
isa<ConstantAggregateZero>(RHS->getOperand(1)))
return Builder->CreateFCmpORD(LHS->getOperand(0), RHS->getOperand(0));
return nullptr;
}
Value *Op0LHS = LHS->getOperand(0), *Op0RHS = LHS->getOperand(1);
Value *Op1LHS = RHS->getOperand(0), *Op1RHS = RHS->getOperand(1);
FCmpInst::Predicate Op0CC = LHS->getPredicate(), Op1CC = RHS->getPredicate();
if (Op0LHS == Op1RHS && Op0RHS == Op1LHS) {
// Swap RHS operands to match LHS.
Op1CC = FCmpInst::getSwappedPredicate(Op1CC);
std::swap(Op1LHS, Op1RHS);
}
if (Op0LHS == Op1LHS && Op0RHS == Op1RHS) {
// Simplify (fcmp cc0 x, y) & (fcmp cc1 x, y).
if (Op0CC == Op1CC)
return Builder->CreateFCmp((FCmpInst::Predicate)Op0CC, Op0LHS, Op0RHS);
if (Op0CC == FCmpInst::FCMP_FALSE || Op1CC == FCmpInst::FCMP_FALSE)
return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
if (Op0CC == FCmpInst::FCMP_TRUE)
return RHS;
if (Op1CC == FCmpInst::FCMP_TRUE)
return LHS;
bool Op0Ordered;
bool Op1Ordered;
unsigned Op0Pred = getFCmpCode(Op0CC, Op0Ordered);
unsigned Op1Pred = getFCmpCode(Op1CC, Op1Ordered);
// uno && ord -> false
if (Op0Pred == 0 && Op1Pred == 0 && Op0Ordered != Op1Ordered)
return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
if (Op1Pred == 0) {
std::swap(LHS, RHS);
std::swap(Op0Pred, Op1Pred);
std::swap(Op0Ordered, Op1Ordered);
}
if (Op0Pred == 0) {
// uno && ueq -> uno && (uno || eq) -> uno
// ord && olt -> ord && (ord && lt) -> olt
if (!Op0Ordered && (Op0Ordered == Op1Ordered))
return LHS;
if (Op0Ordered && (Op0Ordered == Op1Ordered))
return RHS;
// uno && oeq -> uno && (ord && eq) -> false
if (!Op0Ordered)
return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
// ord && ueq -> ord && (uno || eq) -> oeq
return getFCmpValue(true, Op1Pred, Op0LHS, Op0RHS, Builder);
}
}
return nullptr;
}
Instruction *InstCombiner::visitAnd(BinaryOperator &I) {
bool Changed = SimplifyAssociativeOrCommutative(I);
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifyAndInst(Op0, Op1, DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
// (A|B)&(A|C) -> A|(B&C) etc
if (Value *V = SimplifyUsingDistributiveLaws(I))
return ReplaceInstUsesWith(I, V);
// See if we can simplify any instructions used by the instruction whose sole
// purpose is to compute bits we don't care about.
if (SimplifyDemandedInstructionBits(I))
return &I;
if (Value *V = SimplifyBSwap(I))
return ReplaceInstUsesWith(I, V);
if (ConstantInt *AndRHS = dyn_cast<ConstantInt>(Op1)) {
const APInt &AndRHSMask = AndRHS->getValue();
// Optimize a variety of ((val OP C1) & C2) combinations...
if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0)) {
Value *Op0LHS = Op0I->getOperand(0);
Value *Op0RHS = Op0I->getOperand(1);
switch (Op0I->getOpcode()) {
default: break;
case Instruction::Xor:
case Instruction::Or: {
// If the mask is only needed on one incoming arm, push it up.
if (!Op0I->hasOneUse()) break;
APInt NotAndRHS(~AndRHSMask);
if (MaskedValueIsZero(Op0LHS, NotAndRHS, 0, &I)) {
// Not masking anything out for the LHS, move to RHS.
Value *NewRHS = Builder->CreateAnd(Op0RHS, AndRHS,
Op0RHS->getName()+".masked");
return BinaryOperator::Create(Op0I->getOpcode(), Op0LHS, NewRHS);
}
if (!isa<Constant>(Op0RHS) &&
MaskedValueIsZero(Op0RHS, NotAndRHS, 0, &I)) {
// Not masking anything out for the RHS, move to LHS.
Value *NewLHS = Builder->CreateAnd(Op0LHS, AndRHS,
Op0LHS->getName()+".masked");
return BinaryOperator::Create(Op0I->getOpcode(), NewLHS, Op0RHS);
}
break;
}
case Instruction::Add:
// ((A & N) + B) & AndRHS -> (A + B) & AndRHS iff N&AndRHS == AndRHS.
// ((A | N) + B) & AndRHS -> (A + B) & AndRHS iff N&AndRHS == 0
// ((A ^ N) + B) & AndRHS -> (A + B) & AndRHS iff N&AndRHS == 0
if (Value *V = FoldLogicalPlusAnd(Op0LHS, Op0RHS, AndRHS, false, I))
return BinaryOperator::CreateAnd(V, AndRHS);
if (Value *V = FoldLogicalPlusAnd(Op0RHS, Op0LHS, AndRHS, false, I))
return BinaryOperator::CreateAnd(V, AndRHS); // Add commutes
break;
case Instruction::Sub:
// ((A & N) - B) & AndRHS -> (A - B) & AndRHS iff N&AndRHS == AndRHS.
// ((A | N) - B) & AndRHS -> (A - B) & AndRHS iff N&AndRHS == 0
// ((A ^ N) - B) & AndRHS -> (A - B) & AndRHS iff N&AndRHS == 0
if (Value *V = FoldLogicalPlusAnd(Op0LHS, Op0RHS, AndRHS, true, I))
return BinaryOperator::CreateAnd(V, AndRHS);
// (A - N) & AndRHS -> -N & AndRHS iff A&AndRHS==0 and AndRHS
// has 1's for all bits that the subtraction with A might affect.
if (Op0I->hasOneUse() && !match(Op0LHS, m_Zero())) {
uint32_t BitWidth = AndRHSMask.getBitWidth();
uint32_t Zeros = AndRHSMask.countLeadingZeros();
APInt Mask = APInt::getLowBitsSet(BitWidth, BitWidth - Zeros);
if (MaskedValueIsZero(Op0LHS, Mask, 0, &I)) {
Value *NewNeg = Builder->CreateNeg(Op0RHS);
return BinaryOperator::CreateAnd(NewNeg, AndRHS);
}
}
break;
case Instruction::Shl:
case Instruction::LShr:
// (1 << x) & 1 --> zext(x == 0)
// (1 >> x) & 1 --> zext(x == 0)
if (AndRHSMask == 1 && Op0LHS == AndRHS) {
Value *NewICmp =
Builder->CreateICmpEQ(Op0RHS, Constant::getNullValue(I.getType()));
return new ZExtInst(NewICmp, I.getType());
}
break;
}
if (ConstantInt *Op0CI = dyn_cast<ConstantInt>(Op0I->getOperand(1)))
if (Instruction *Res = OptAndOp(Op0I, Op0CI, AndRHS, I))
return Res;
}
// If this is an integer truncation, and if the source is an 'and' with
// immediate, transform it. This frequently occurs for bitfield accesses.
{
Value *X = nullptr; ConstantInt *YC = nullptr;
if (match(Op0, m_Trunc(m_And(m_Value(X), m_ConstantInt(YC))))) {
// Change: and (trunc (and X, YC) to T), C2
// into : and (trunc X to T), trunc(YC) & C2
// This will fold the two constants together, which may allow
// other simplifications.
Value *NewCast = Builder->CreateTrunc(X, I.getType(), "and.shrunk");
Constant *C3 = ConstantExpr::getTrunc(YC, I.getType());
C3 = ConstantExpr::getAnd(C3, AndRHS);
return BinaryOperator::CreateAnd(NewCast, C3);
}
}
// Try to fold constant and into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (isa<PHINode>(Op0))
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
}
// (~A & ~B) == (~(A | B)) - De Morgan's Law
if (Value *Op0NotVal = dyn_castNotVal(Op0))
if (Value *Op1NotVal = dyn_castNotVal(Op1))
if (Op0->hasOneUse() && Op1->hasOneUse()) {
Value *Or = Builder->CreateOr(Op0NotVal, Op1NotVal,
I.getName()+".demorgan");
return BinaryOperator::CreateNot(Or);
}
{
Value *A = nullptr, *B = nullptr, *C = nullptr, *D = nullptr;
// (A|B) & ~(A&B) -> A^B
if (match(Op0, m_Or(m_Value(A), m_Value(B))) &&
match(Op1, m_Not(m_And(m_Value(C), m_Value(D)))) &&
((A == C && B == D) || (A == D && B == C)))
return BinaryOperator::CreateXor(A, B);
// ~(A&B) & (A|B) -> A^B
if (match(Op1, m_Or(m_Value(A), m_Value(B))) &&
match(Op0, m_Not(m_And(m_Value(C), m_Value(D)))) &&
((A == C && B == D) || (A == D && B == C)))
return BinaryOperator::CreateXor(A, B);
// A&(A^B) => A & ~B
{
Value *tmpOp0 = Op0;
Value *tmpOp1 = Op1;
if (Op0->hasOneUse() &&
match(Op0, m_Xor(m_Value(A), m_Value(B)))) {
if (A == Op1 || B == Op1 ) {
tmpOp1 = Op0;
tmpOp0 = Op1;
// Simplify below
}
}
if (tmpOp1->hasOneUse() &&
match(tmpOp1, m_Xor(m_Value(A), m_Value(B)))) {
if (B == tmpOp0) {
std::swap(A, B);
}
// Notice that the patten (A&(~B)) is actually (A&(-1^B)), so if
// A is originally -1 (or a vector of -1 and undefs), then we enter
// an endless loop. By checking that A is non-constant we ensure that
// we will never get to the loop.
if (A == tmpOp0 && !isa<Constant>(A)) // A&(A^B) -> A & ~B
return BinaryOperator::CreateAnd(A, Builder->CreateNot(B));
}
}
// (A&((~A)|B)) -> A&B
if (match(Op0, m_Or(m_Not(m_Specific(Op1)), m_Value(A))) ||
match(Op0, m_Or(m_Value(A), m_Not(m_Specific(Op1)))))
return BinaryOperator::CreateAnd(A, Op1);
if (match(Op1, m_Or(m_Not(m_Specific(Op0)), m_Value(A))) ||
match(Op1, m_Or(m_Value(A), m_Not(m_Specific(Op0)))))
return BinaryOperator::CreateAnd(A, Op0);
// (A ^ B) & ((B ^ C) ^ A) -> (A ^ B) & ~C
if (match(Op0, m_Xor(m_Value(A), m_Value(B))))
if (match(Op1, m_Xor(m_Xor(m_Specific(B), m_Value(C)), m_Specific(A))))
if (Op1->hasOneUse() || cast<BinaryOperator>(Op1)->hasOneUse())
return BinaryOperator::CreateAnd(Op0, Builder->CreateNot(C));
// ((A ^ C) ^ B) & (B ^ A) -> (B ^ A) & ~C
if (match(Op0, m_Xor(m_Xor(m_Value(A), m_Value(C)), m_Value(B))))
if (match(Op1, m_Xor(m_Specific(B), m_Specific(A))))
if (Op0->hasOneUse() || cast<BinaryOperator>(Op0)->hasOneUse())
return BinaryOperator::CreateAnd(Op1, Builder->CreateNot(C));
// (A | B) & ((~A) ^ B) -> (A & B)
if (match(Op0, m_Or(m_Value(A), m_Value(B))) &&
match(Op1, m_Xor(m_Not(m_Specific(A)), m_Specific(B))))
return BinaryOperator::CreateAnd(A, B);
// ((~A) ^ B) & (A | B) -> (A & B)
if (match(Op0, m_Xor(m_Not(m_Value(A)), m_Value(B))) &&
match(Op1, m_Or(m_Specific(A), m_Specific(B))))
return BinaryOperator::CreateAnd(A, B);
}
{
ICmpInst *LHS = dyn_cast<ICmpInst>(Op0);
ICmpInst *RHS = dyn_cast<ICmpInst>(Op1);
if (LHS && RHS)
if (Value *Res = FoldAndOfICmps(LHS, RHS))
return ReplaceInstUsesWith(I, Res);
// TODO: Make this recursive; it's a little tricky because an arbitrary
// number of 'and' instructions might have to be created.
Value *X, *Y;
if (LHS && match(Op1, m_OneUse(m_And(m_Value(X), m_Value(Y))))) {
if (auto *Cmp = dyn_cast<ICmpInst>(X))
if (Value *Res = FoldAndOfICmps(LHS, Cmp))
return ReplaceInstUsesWith(I, Builder->CreateAnd(Res, Y));
if (auto *Cmp = dyn_cast<ICmpInst>(Y))
if (Value *Res = FoldAndOfICmps(LHS, Cmp))
return ReplaceInstUsesWith(I, Builder->CreateAnd(Res, X));
}
if (RHS && match(Op0, m_OneUse(m_And(m_Value(X), m_Value(Y))))) {
if (auto *Cmp = dyn_cast<ICmpInst>(X))
if (Value *Res = FoldAndOfICmps(Cmp, RHS))
return ReplaceInstUsesWith(I, Builder->CreateAnd(Res, Y));
if (auto *Cmp = dyn_cast<ICmpInst>(Y))
if (Value *Res = FoldAndOfICmps(Cmp, RHS))
return ReplaceInstUsesWith(I, Builder->CreateAnd(Res, X));
}
}
// If and'ing two fcmp, try combine them into one.
if (FCmpInst *LHS = dyn_cast<FCmpInst>(I.getOperand(0)))
if (FCmpInst *RHS = dyn_cast<FCmpInst>(I.getOperand(1)))
if (Value *Res = FoldAndOfFCmps(LHS, RHS))
return ReplaceInstUsesWith(I, Res);
// fold (and (cast A), (cast B)) -> (cast (and A, B))
if (CastInst *Op0C = dyn_cast<CastInst>(Op0))
if (CastInst *Op1C = dyn_cast<CastInst>(Op1)) {
Type *SrcTy = Op0C->getOperand(0)->getType();
if (Op0C->getOpcode() == Op1C->getOpcode() && // same cast kind ?
SrcTy == Op1C->getOperand(0)->getType() &&
SrcTy->isIntOrIntVectorTy()) {
Value *Op0COp = Op0C->getOperand(0), *Op1COp = Op1C->getOperand(0);
// Only do this if the casts both really cause code to be generated.
if (ShouldOptimizeCast(Op0C->getOpcode(), Op0COp, I.getType()) &&
ShouldOptimizeCast(Op1C->getOpcode(), Op1COp, I.getType())) {
Value *NewOp = Builder->CreateAnd(Op0COp, Op1COp, I.getName());
return CastInst::Create(Op0C->getOpcode(), NewOp, I.getType());
}
// If this is and(cast(icmp), cast(icmp)), try to fold this even if the
// cast is otherwise not optimizable. This happens for vector sexts.
if (ICmpInst *RHS = dyn_cast<ICmpInst>(Op1COp))
if (ICmpInst *LHS = dyn_cast<ICmpInst>(Op0COp))
if (Value *Res = FoldAndOfICmps(LHS, RHS))
return CastInst::Create(Op0C->getOpcode(), Res, I.getType());
// If this is and(cast(fcmp), cast(fcmp)), try to fold this even if the
// cast is otherwise not optimizable. This happens for vector sexts.
if (FCmpInst *RHS = dyn_cast<FCmpInst>(Op1COp))
if (FCmpInst *LHS = dyn_cast<FCmpInst>(Op0COp))
if (Value *Res = FoldAndOfFCmps(LHS, RHS))
return CastInst::Create(Op0C->getOpcode(), Res, I.getType());
}
}
{
Value *X = nullptr;
bool OpsSwapped = false;
// Canonicalize SExt or Not to the LHS
if (match(Op1, m_SExt(m_Value())) ||
match(Op1, m_Not(m_Value()))) {
std::swap(Op0, Op1);
OpsSwapped = true;
}
// Fold (and (sext bool to A), B) --> (select bool, B, 0)
if (match(Op0, m_SExt(m_Value(X))) &&
X->getType()->getScalarType()->isIntegerTy(1)) {
Value *Zero = Constant::getNullValue(Op1->getType());
return SelectInst::Create(X, Op1, Zero);
}
// Fold (and ~(sext bool to A), B) --> (select bool, 0, B)
if (match(Op0, m_Not(m_SExt(m_Value(X)))) &&
X->getType()->getScalarType()->isIntegerTy(1)) {
Value *Zero = Constant::getNullValue(Op0->getType());
return SelectInst::Create(X, Zero, Op1);
}
if (OpsSwapped)
std::swap(Op0, Op1);
}
return Changed ? &I : nullptr;
}
/// CollectBSwapParts - Analyze the specified subexpression and see if it is
/// capable of providing pieces of a bswap. The subexpression provides pieces
/// of a bswap if it is proven that each of the non-zero bytes in the output of
/// the expression came from the corresponding "byte swapped" byte in some other
/// value. For example, if the current subexpression is "(shl i32 %X, 24)" then
/// we know that the expression deposits the low byte of %X into the high byte
/// of the bswap result and that all other bytes are zero. This expression is
/// accepted, the high byte of ByteValues is set to X to indicate a correct
/// match.
///
/// This function returns true if the match was unsuccessful and false if so.
/// On entry to the function the "OverallLeftShift" is a signed integer value
/// indicating the number of bytes that the subexpression is later shifted. For
/// example, if the expression is later right shifted by 16 bits, the
/// OverallLeftShift value would be -2 on entry. This is used to specify which
/// byte of ByteValues is actually being set.
///
/// Similarly, ByteMask is a bitmask where a bit is clear if its corresponding
/// byte is masked to zero by a user. For example, in (X & 255), X will be
/// processed with a bytemask of 1. Because bytemask is 32-bits, this limits
/// this function to working on up to 32-byte (256 bit) values. ByteMask is
/// always in the local (OverallLeftShift) coordinate space.
///
static bool CollectBSwapParts(Value *V, int OverallLeftShift, uint32_t ByteMask,
SmallVectorImpl<Value *> &ByteValues) {
if (Instruction *I = dyn_cast<Instruction>(V)) {
// If this is an or instruction, it may be an inner node of the bswap.
if (I->getOpcode() == Instruction::Or) {
return CollectBSwapParts(I->getOperand(0), OverallLeftShift, ByteMask,
ByteValues) ||
CollectBSwapParts(I->getOperand(1), OverallLeftShift, ByteMask,
ByteValues);
}
// If this is a logical shift by a constant multiple of 8, recurse with
// OverallLeftShift and ByteMask adjusted.
if (I->isLogicalShift() && isa<ConstantInt>(I->getOperand(1))) {
unsigned ShAmt =
cast<ConstantInt>(I->getOperand(1))->getLimitedValue(~0U);
// Ensure the shift amount is defined and of a byte value.
if ((ShAmt & 7) || (ShAmt > 8*ByteValues.size()))
return true;
unsigned ByteShift = ShAmt >> 3;
if (I->getOpcode() == Instruction::Shl) {
// X << 2 -> collect(X, +2)
OverallLeftShift += ByteShift;
ByteMask >>= ByteShift;
} else {
// X >>u 2 -> collect(X, -2)
OverallLeftShift -= ByteShift;
ByteMask <<= ByteShift;
ByteMask &= (~0U >> (32-ByteValues.size()));
}
if (OverallLeftShift >= (int)ByteValues.size()) return true;
if (OverallLeftShift <= -(int)ByteValues.size()) return true;
return CollectBSwapParts(I->getOperand(0), OverallLeftShift, ByteMask,
ByteValues);
}
// If this is a logical 'and' with a mask that clears bytes, clear the
// corresponding bytes in ByteMask.
if (I->getOpcode() == Instruction::And &&
isa<ConstantInt>(I->getOperand(1))) {
// Scan every byte of the and mask, seeing if the byte is either 0 or 255.
unsigned NumBytes = ByteValues.size();
APInt Byte(I->getType()->getPrimitiveSizeInBits(), 255);
const APInt &AndMask = cast<ConstantInt>(I->getOperand(1))->getValue();
for (unsigned i = 0; i != NumBytes; ++i, Byte <<= 8) {
// If this byte is masked out by a later operation, we don't care what
// the and mask is.
if ((ByteMask & (1 << i)) == 0)
continue;
// If the AndMask is all zeros for this byte, clear the bit.
APInt MaskB = AndMask & Byte;
if (MaskB == 0) {
ByteMask &= ~(1U << i);
continue;
}
// If the AndMask is not all ones for this byte, it's not a bytezap.
if (MaskB != Byte)
return true;
// Otherwise, this byte is kept.
}
return CollectBSwapParts(I->getOperand(0), OverallLeftShift, ByteMask,
ByteValues);
}
}
// Okay, we got to something that isn't a shift, 'or' or 'and'. This must be
// the input value to the bswap. Some observations: 1) if more than one byte
// is demanded from this input, then it could not be successfully assembled
// into a byteswap. At least one of the two bytes would not be aligned with
// their ultimate destination.
if (!isPowerOf2_32(ByteMask)) return true;
unsigned InputByteNo = countTrailingZeros(ByteMask);
// 2) The input and ultimate destinations must line up: if byte 3 of an i32
// is demanded, it needs to go into byte 0 of the result. This means that the
// byte needs to be shifted until it lands in the right byte bucket. The
// shift amount depends on the position: if the byte is coming from the high
// part of the value (e.g. byte 3) then it must be shifted right. If from the
// low part, it must be shifted left.
unsigned DestByteNo = InputByteNo + OverallLeftShift;
if (ByteValues.size()-1-DestByteNo != InputByteNo)
return true;
// If the destination byte value is already defined, the values are or'd
// together, which isn't a bswap (unless it's an or of the same bits).
if (ByteValues[DestByteNo] && ByteValues[DestByteNo] != V)
return true;
ByteValues[DestByteNo] = V;
return false;
}
/// MatchBSwap - Given an OR instruction, check to see if this is a bswap idiom.
/// If so, insert the new bswap intrinsic and return it.
Instruction *InstCombiner::MatchBSwap(BinaryOperator &I) {
// HLSL Change begin - Disable bswap matching for DXIL.
Triple T(I.getModule()->getTargetTriple());
if (T.isDXIL())
return nullptr;
// HLSL Change end - Disable bswap matching for DXIL.
IntegerType *ITy = dyn_cast<IntegerType>(I.getType());
if (!ITy || ITy->getBitWidth() % 16 ||
// ByteMask only allows up to 32-byte values.
ITy->getBitWidth() > 32*8)
return nullptr; // Can only bswap pairs of bytes. Can't do vectors.
/// ByteValues - For each byte of the result, we keep track of which value
/// defines each byte.
SmallVector<Value*, 8> ByteValues;
ByteValues.resize(ITy->getBitWidth()/8);
// Try to find all the pieces corresponding to the bswap.
uint32_t ByteMask = ~0U >> (32-ByteValues.size());
if (CollectBSwapParts(&I, 0, ByteMask, ByteValues))
return nullptr;
// Check to see if all of the bytes come from the same value.
Value *V = ByteValues[0];
if (!V) return nullptr; // Didn't find a byte? Must be zero.
// Check to make sure that all of the bytes come from the same value.
for (unsigned i = 1, e = ByteValues.size(); i != e; ++i)
if (ByteValues[i] != V)
return nullptr;
Module *M = I.getParent()->getParent()->getParent();
Function *F = Intrinsic::getDeclaration(M, Intrinsic::bswap, ITy);
return CallInst::Create(F, V);
}
/// MatchSelectFromAndOr - We have an expression of the form (A&C)|(B&D). Check
/// If A is (cond?-1:0) and either B or D is ~(cond?-1,0) or (cond?0,-1), then
/// we can simplify this expression to "cond ? C : D or B".
static Instruction *MatchSelectFromAndOr(Value *A, Value *B,
Value *C, Value *D) {
// If A is not a select of -1/0, this cannot match.
Value *Cond = nullptr;
if (!match(A, m_SExt(m_Value(Cond))) ||
!Cond->getType()->isIntegerTy(1))
return nullptr;
// ((cond?-1:0)&C) | (B&(cond?0:-1)) -> cond ? C : B.
if (match(D, m_Not(m_SExt(m_Specific(Cond)))))
return SelectInst::Create(Cond, C, B);
if (match(D, m_SExt(m_Not(m_Specific(Cond)))))
return SelectInst::Create(Cond, C, B);
// ((cond?-1:0)&C) | ((cond?0:-1)&D) -> cond ? C : D.
if (match(B, m_Not(m_SExt(m_Specific(Cond)))))
return SelectInst::Create(Cond, C, D);
if (match(B, m_SExt(m_Not(m_Specific(Cond)))))
return SelectInst::Create(Cond, C, D);
return nullptr;
}
/// FoldOrOfICmps - Fold (icmp)|(icmp) if possible.
Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS,
Instruction *CxtI) {
ICmpInst::Predicate LHSCC = LHS->getPredicate(), RHSCC = RHS->getPredicate();
// Fold (iszero(A & K1) | iszero(A & K2)) -> (A & (K1 | K2)) != (K1 | K2)
// if K1 and K2 are a one-bit mask.
ConstantInt *LHSCst = dyn_cast<ConstantInt>(LHS->getOperand(1));
ConstantInt *RHSCst = dyn_cast<ConstantInt>(RHS->getOperand(1));
if (LHS->getPredicate() == ICmpInst::ICMP_EQ && LHSCst && LHSCst->isZero() &&
RHS->getPredicate() == ICmpInst::ICMP_EQ && RHSCst && RHSCst->isZero()) {
BinaryOperator *LAnd = dyn_cast<BinaryOperator>(LHS->getOperand(0));
BinaryOperator *RAnd = dyn_cast<BinaryOperator>(RHS->getOperand(0));
if (LAnd && RAnd && LAnd->hasOneUse() && RHS->hasOneUse() &&
LAnd->getOpcode() == Instruction::And &&
RAnd->getOpcode() == Instruction::And) {
Value *Mask = nullptr;
Value *Masked = nullptr;
if (LAnd->getOperand(0) == RAnd->getOperand(0) &&
isKnownToBeAPowerOfTwo(LAnd->getOperand(1), DL, false, 0, AC, CxtI,
DT) &&
isKnownToBeAPowerOfTwo(RAnd->getOperand(1), DL, false, 0, AC, CxtI,
DT)) {
Mask = Builder->CreateOr(LAnd->getOperand(1), RAnd->getOperand(1));
Masked = Builder->CreateAnd(LAnd->getOperand(0), Mask);
} else if (LAnd->getOperand(1) == RAnd->getOperand(1) &&
isKnownToBeAPowerOfTwo(LAnd->getOperand(0), DL, false, 0, AC,
CxtI, DT) &&
isKnownToBeAPowerOfTwo(RAnd->getOperand(0), DL, false, 0, AC,
CxtI, DT)) {
Mask = Builder->CreateOr(LAnd->getOperand(0), RAnd->getOperand(0));
Masked = Builder->CreateAnd(LAnd->getOperand(1), Mask);
}
if (Masked)
return Builder->CreateICmp(ICmpInst::ICMP_NE, Masked, Mask);
}
}
// Fold (icmp ult/ule (A + C1), C3) | (icmp ult/ule (A + C2), C3)
// --> (icmp ult/ule ((A & ~(C1 ^ C2)) + max(C1, C2)), C3)
// The original condition actually refers to the following two ranges:
// [MAX_UINT-C1+1, MAX_UINT-C1+1+C3] and [MAX_UINT-C2+1, MAX_UINT-C2+1+C3]
// We can fold these two ranges if:
// 1) C1 and C2 is unsigned greater than C3.
// 2) The two ranges are separated.
// 3) C1 ^ C2 is one-bit mask.
// 4) LowRange1 ^ LowRange2 and HighRange1 ^ HighRange2 are one-bit mask.
// This implies all values in the two ranges differ by exactly one bit.
if ((LHSCC == ICmpInst::ICMP_ULT || LHSCC == ICmpInst::ICMP_ULE) &&
LHSCC == RHSCC && LHSCst && RHSCst && LHS->hasOneUse() &&
RHS->hasOneUse() && LHSCst->getType() == RHSCst->getType() &&
LHSCst->getValue() == (RHSCst->getValue())) {
Value *LAdd = LHS->getOperand(0);
Value *RAdd = RHS->getOperand(0);
Value *LAddOpnd, *RAddOpnd;
ConstantInt *LAddCst, *RAddCst;
if (match(LAdd, m_Add(m_Value(LAddOpnd), m_ConstantInt(LAddCst))) &&
match(RAdd, m_Add(m_Value(RAddOpnd), m_ConstantInt(RAddCst))) &&
LAddCst->getValue().ugt(LHSCst->getValue()) &&
RAddCst->getValue().ugt(LHSCst->getValue())) {
APInt DiffCst = LAddCst->getValue() ^ RAddCst->getValue();
if (LAddOpnd == RAddOpnd && DiffCst.isPowerOf2()) {
ConstantInt *MaxAddCst = nullptr;
if (LAddCst->getValue().ult(RAddCst->getValue()))
MaxAddCst = RAddCst;
else
MaxAddCst = LAddCst;
APInt RRangeLow = -RAddCst->getValue();
APInt RRangeHigh = RRangeLow + LHSCst->getValue();
APInt LRangeLow = -LAddCst->getValue();
APInt LRangeHigh = LRangeLow + LHSCst->getValue();
APInt LowRangeDiff = RRangeLow ^ LRangeLow;
APInt HighRangeDiff = RRangeHigh ^ LRangeHigh;
APInt RangeDiff = LRangeLow.sgt(RRangeLow) ? LRangeLow - RRangeLow
: RRangeLow - LRangeLow;
if (LowRangeDiff.isPowerOf2() && LowRangeDiff == HighRangeDiff &&
RangeDiff.ugt(LHSCst->getValue())) {
Value *MaskCst = ConstantInt::get(LAddCst->getType(), ~DiffCst);
Value *NewAnd = Builder->CreateAnd(LAddOpnd, MaskCst);
Value *NewAdd = Builder->CreateAdd(NewAnd, MaxAddCst);
return (Builder->CreateICmp(LHS->getPredicate(), NewAdd, LHSCst));
}
}
}
}
// (icmp1 A, B) | (icmp2 A, B) --> (icmp3 A, B)
if (PredicatesFoldable(LHSCC, RHSCC)) {
if (LHS->getOperand(0) == RHS->getOperand(1) &&
LHS->getOperand(1) == RHS->getOperand(0))
LHS->swapOperands();
if (LHS->getOperand(0) == RHS->getOperand(0) &&
LHS->getOperand(1) == RHS->getOperand(1)) {
Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
unsigned Code = getICmpCode(LHS) | getICmpCode(RHS);
bool isSigned = LHS->isSigned() || RHS->isSigned();
return getNewICmpValue(isSigned, Code, Op0, Op1, Builder);
}
}
// handle (roughly):
// (icmp ne (A & B), C) | (icmp ne (A & D), E)
if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, false, Builder))
return V;
Value *Val = LHS->getOperand(0), *Val2 = RHS->getOperand(0);
if (LHS->hasOneUse() || RHS->hasOneUse()) {
// (icmp eq B, 0) | (icmp ult A, B) -> (icmp ule A, B-1)
// (icmp eq B, 0) | (icmp ugt B, A) -> (icmp ule A, B-1)
Value *A = nullptr, *B = nullptr;
if (LHSCC == ICmpInst::ICMP_EQ && LHSCst && LHSCst->isZero()) {
B = Val;
if (RHSCC == ICmpInst::ICMP_ULT && Val == RHS->getOperand(1))
A = Val2;
else if (RHSCC == ICmpInst::ICMP_UGT && Val == Val2)
A = RHS->getOperand(1);
}
// (icmp ult A, B) | (icmp eq B, 0) -> (icmp ule A, B-1)
// (icmp ugt B, A) | (icmp eq B, 0) -> (icmp ule A, B-1)
else if (RHSCC == ICmpInst::ICMP_EQ && RHSCst && RHSCst->isZero()) {
B = Val2;
if (LHSCC == ICmpInst::ICMP_ULT && Val2 == LHS->getOperand(1))
A = Val;
else if (LHSCC == ICmpInst::ICMP_UGT && Val2 == Val)
A = LHS->getOperand(1);
}
if (A && B)
return Builder->CreateICmp(
ICmpInst::ICMP_UGE,
Builder->CreateAdd(B, ConstantInt::getSigned(B->getType(), -1)), A);
}
// E.g. (icmp slt x, 0) | (icmp sgt x, n) --> icmp ugt x, n
if (Value *V = simplifyRangeCheck(LHS, RHS, /*Inverted=*/true))
return V;
// E.g. (icmp sgt x, n) | (icmp slt x, 0) --> icmp ugt x, n
if (Value *V = simplifyRangeCheck(RHS, LHS, /*Inverted=*/true))
return V;
// This only handles icmp of constants: (icmp1 A, C1) | (icmp2 B, C2).
if (!LHSCst || !RHSCst) return nullptr;
if (LHSCst == RHSCst && LHSCC == RHSCC) {
// (icmp ne A, 0) | (icmp ne B, 0) --> (icmp ne (A|B), 0)
if (LHSCC == ICmpInst::ICMP_NE && LHSCst->isZero()) {
Value *NewOr = Builder->CreateOr(Val, Val2);
return Builder->CreateICmp(LHSCC, NewOr, LHSCst);
}
}
// (icmp ult (X + CA), C1) | (icmp eq X, C2) -> (icmp ule (X + CA), C1)
// iff C2 + CA == C1.
if (LHSCC == ICmpInst::ICMP_ULT && RHSCC == ICmpInst::ICMP_EQ) {
ConstantInt *AddCst;
if (match(Val, m_Add(m_Specific(Val2), m_ConstantInt(AddCst))))
if (RHSCst->getValue() + AddCst->getValue() == LHSCst->getValue())
return Builder->CreateICmpULE(Val, LHSCst);
}
// From here on, we only handle:
// (icmp1 A, C1) | (icmp2 A, C2) --> something simpler.
if (Val != Val2) return nullptr;
// ICMP_[US][GL]E X, CST is folded to ICMP_[US][GL]T elsewhere.
if (LHSCC == ICmpInst::ICMP_UGE || LHSCC == ICmpInst::ICMP_ULE ||
RHSCC == ICmpInst::ICMP_UGE || RHSCC == ICmpInst::ICMP_ULE ||
LHSCC == ICmpInst::ICMP_SGE || LHSCC == ICmpInst::ICMP_SLE ||
RHSCC == ICmpInst::ICMP_SGE || RHSCC == ICmpInst::ICMP_SLE)
return nullptr;
// We can't fold (ugt x, C) | (sgt x, C2).
if (!PredicatesFoldable(LHSCC, RHSCC))
return nullptr;
// Ensure that the larger constant is on the RHS.
bool ShouldSwap;
if (CmpInst::isSigned(LHSCC) ||
(ICmpInst::isEquality(LHSCC) &&
CmpInst::isSigned(RHSCC)))
ShouldSwap = LHSCst->getValue().sgt(RHSCst->getValue());
else
ShouldSwap = LHSCst->getValue().ugt(RHSCst->getValue());
if (ShouldSwap) {
std::swap(LHS, RHS);
std::swap(LHSCst, RHSCst);
std::swap(LHSCC, RHSCC);
}
// At this point, we know we have two icmp instructions
// comparing a value against two constants and or'ing the result
// together. Because of the above check, we know that we only have
// ICMP_EQ, ICMP_NE, ICMP_LT, and ICMP_GT here. We also know (from the
// icmp folding check above), that the two constants are not
// equal.
assert(LHSCst != RHSCst && "Compares not folded above?");
switch (LHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
case ICmpInst::ICMP_EQ:
switch (RHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
case ICmpInst::ICMP_EQ:
if (LHS->getOperand(0) == RHS->getOperand(0)) {
// if LHSCst and RHSCst differ only by one bit:
// (A == C1 || A == C2) -> (A & ~(C1 ^ C2)) == C1
assert(LHSCst->getValue().ule(LHSCst->getValue()));
APInt Xor = LHSCst->getValue() ^ RHSCst->getValue();
if (Xor.isPowerOf2()) {
Value *NegCst = Builder->getInt(~Xor);
Value *And = Builder->CreateAnd(LHS->getOperand(0), NegCst);
return Builder->CreateICmp(ICmpInst::ICMP_EQ, And, LHSCst);
}
}
if (LHSCst == SubOne(RHSCst)) {
// (X == 13 | X == 14) -> X-13 <u 2
Constant *AddCST = ConstantExpr::getNeg(LHSCst);
Value *Add = Builder->CreateAdd(Val, AddCST, Val->getName()+".off");
AddCST = ConstantExpr::getSub(AddOne(RHSCst), LHSCst);
return Builder->CreateICmpULT(Add, AddCST);
}
break; // (X == 13 | X == 15) -> no change
case ICmpInst::ICMP_UGT: // (X == 13 | X u> 14) -> no change
case ICmpInst::ICMP_SGT: // (X == 13 | X s> 14) -> no change
break;
case ICmpInst::ICMP_NE: // (X == 13 | X != 15) -> X != 15
case ICmpInst::ICMP_ULT: // (X == 13 | X u< 15) -> X u< 15
case ICmpInst::ICMP_SLT: // (X == 13 | X s< 15) -> X s< 15
return RHS;
}
break;
case ICmpInst::ICMP_NE:
switch (RHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
case ICmpInst::ICMP_EQ: // (X != 13 | X == 15) -> X != 13
case ICmpInst::ICMP_UGT: // (X != 13 | X u> 15) -> X != 13
case ICmpInst::ICMP_SGT: // (X != 13 | X s> 15) -> X != 13
return LHS;
case ICmpInst::ICMP_NE: // (X != 13 | X != 15) -> true
case ICmpInst::ICMP_ULT: // (X != 13 | X u< 15) -> true
case ICmpInst::ICMP_SLT: // (X != 13 | X s< 15) -> true
return Builder->getTrue();
}
case ICmpInst::ICMP_ULT:
switch (RHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
case ICmpInst::ICMP_EQ: // (X u< 13 | X == 14) -> no change
break;
case ICmpInst::ICMP_UGT: // (X u< 13 | X u> 15) -> (X-13) u> 2
// If RHSCst is [us]MAXINT, it is always false. Not handling
// this can cause overflow.
if (RHSCst->isMaxValue(false))
return LHS;
return InsertRangeTest(Val, LHSCst, AddOne(RHSCst), false, false);
case ICmpInst::ICMP_SGT: // (X u< 13 | X s> 15) -> no change
break;
case ICmpInst::ICMP_NE: // (X u< 13 | X != 15) -> X != 15
case ICmpInst::ICMP_ULT: // (X u< 13 | X u< 15) -> X u< 15
return RHS;
case ICmpInst::ICMP_SLT: // (X u< 13 | X s< 15) -> no change
break;
}
break;
case ICmpInst::ICMP_SLT:
switch (RHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
case ICmpInst::ICMP_EQ: // (X s< 13 | X == 14) -> no change
break;
case ICmpInst::ICMP_SGT: // (X s< 13 | X s> 15) -> (X-13) s> 2
// If RHSCst is [us]MAXINT, it is always false. Not handling
// this can cause overflow.
if (RHSCst->isMaxValue(true))
return LHS;
return InsertRangeTest(Val, LHSCst, AddOne(RHSCst), true, false);
case ICmpInst::ICMP_UGT: // (X s< 13 | X u> 15) -> no change
break;
case ICmpInst::ICMP_NE: // (X s< 13 | X != 15) -> X != 15
case ICmpInst::ICMP_SLT: // (X s< 13 | X s< 15) -> X s< 15
return RHS;
case ICmpInst::ICMP_ULT: // (X s< 13 | X u< 15) -> no change
break;
}
break;
case ICmpInst::ICMP_UGT:
switch (RHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
case ICmpInst::ICMP_EQ: // (X u> 13 | X == 15) -> X u> 13
case ICmpInst::ICMP_UGT: // (X u> 13 | X u> 15) -> X u> 13
return LHS;
case ICmpInst::ICMP_SGT: // (X u> 13 | X s> 15) -> no change
break;
case ICmpInst::ICMP_NE: // (X u> 13 | X != 15) -> true
case ICmpInst::ICMP_ULT: // (X u> 13 | X u< 15) -> true
return Builder->getTrue();
case ICmpInst::ICMP_SLT: // (X u> 13 | X s< 15) -> no change
break;
}
break;
case ICmpInst::ICMP_SGT:
switch (RHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
case ICmpInst::ICMP_EQ: // (X s> 13 | X == 15) -> X > 13
case ICmpInst::ICMP_SGT: // (X s> 13 | X s> 15) -> X > 13
return LHS;
case ICmpInst::ICMP_UGT: // (X s> 13 | X u> 15) -> no change
break;
case ICmpInst::ICMP_NE: // (X s> 13 | X != 15) -> true
case ICmpInst::ICMP_SLT: // (X s> 13 | X s< 15) -> true
return Builder->getTrue();
case ICmpInst::ICMP_ULT: // (X s> 13 | X u< 15) -> no change
break;
}
break;
}
return nullptr;
}
/// FoldOrOfFCmps - Optimize (fcmp)|(fcmp). NOTE: Unlike the rest of
/// instcombine, this returns a Value which should already be inserted into the
/// function.
Value *InstCombiner::FoldOrOfFCmps(FCmpInst *LHS, FCmpInst *RHS) {
if (LHS->getPredicate() == FCmpInst::FCMP_UNO &&
RHS->getPredicate() == FCmpInst::FCMP_UNO &&
LHS->getOperand(0)->getType() == RHS->getOperand(0)->getType()) {
if (ConstantFP *LHSC = dyn_cast<ConstantFP>(LHS->getOperand(1)))
if (ConstantFP *RHSC = dyn_cast<ConstantFP>(RHS->getOperand(1))) {
// If either of the constants are nans, then the whole thing returns
// true.
if (LHSC->getValueAPF().isNaN() || RHSC->getValueAPF().isNaN())
return Builder->getTrue();
// Otherwise, no need to compare the two constants, compare the
// rest.
return Builder->CreateFCmpUNO(LHS->getOperand(0), RHS->getOperand(0));
}
// Handle vector zeros. This occurs because the canonical form of
// "fcmp uno x,x" is "fcmp uno x, 0".
if (isa<ConstantAggregateZero>(LHS->getOperand(1)) &&
isa<ConstantAggregateZero>(RHS->getOperand(1)))
return Builder->CreateFCmpUNO(LHS->getOperand(0), RHS->getOperand(0));
return nullptr;
}
Value *Op0LHS = LHS->getOperand(0), *Op0RHS = LHS->getOperand(1);
Value *Op1LHS = RHS->getOperand(0), *Op1RHS = RHS->getOperand(1);
FCmpInst::Predicate Op0CC = LHS->getPredicate(), Op1CC = RHS->getPredicate();
if (Op0LHS == Op1RHS && Op0RHS == Op1LHS) {
// Swap RHS operands to match LHS.
Op1CC = FCmpInst::getSwappedPredicate(Op1CC);
std::swap(Op1LHS, Op1RHS);
}
if (Op0LHS == Op1LHS && Op0RHS == Op1RHS) {
// Simplify (fcmp cc0 x, y) | (fcmp cc1 x, y).
if (Op0CC == Op1CC)
return Builder->CreateFCmp((FCmpInst::Predicate)Op0CC, Op0LHS, Op0RHS);
if (Op0CC == FCmpInst::FCMP_TRUE || Op1CC == FCmpInst::FCMP_TRUE)
return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 1);
if (Op0CC == FCmpInst::FCMP_FALSE)
return RHS;
if (Op1CC == FCmpInst::FCMP_FALSE)
return LHS;
bool Op0Ordered;
bool Op1Ordered;
unsigned Op0Pred = getFCmpCode(Op0CC, Op0Ordered);
unsigned Op1Pred = getFCmpCode(Op1CC, Op1Ordered);
if (Op0Ordered == Op1Ordered) {
// If both are ordered or unordered, return a new fcmp with
// or'ed predicates.
return getFCmpValue(Op0Ordered, Op0Pred|Op1Pred, Op0LHS, Op0RHS, Builder);
}
}
return nullptr;
}
/// FoldOrWithConstants - This helper function folds:
///
/// ((A | B) & C1) | (B & C2)
///
/// into:
///
/// (A & C1) | B
///
/// when the XOR of the two constants is "all ones" (-1).
Instruction *InstCombiner::FoldOrWithConstants(BinaryOperator &I, Value *Op,
Value *A, Value *B, Value *C) {
ConstantInt *CI1 = dyn_cast<ConstantInt>(C);
if (!CI1) return nullptr;
Value *V1 = nullptr;
ConstantInt *CI2 = nullptr;
if (!match(Op, m_And(m_Value(V1), m_ConstantInt(CI2)))) return nullptr;
APInt Xor = CI1->getValue() ^ CI2->getValue();
if (!Xor.isAllOnesValue()) return nullptr;
if (V1 == A || V1 == B) {
Value *NewOp = Builder->CreateAnd((V1 == A) ? B : A, CI1);
return BinaryOperator::CreateOr(NewOp, V1);
}
return nullptr;
}
/// \brief This helper function folds:
///
/// ((A | B) & C1) ^ (B & C2)
///
/// into:
///
/// (A & C1) ^ B
///
/// when the XOR of the two constants is "all ones" (-1).
Instruction *InstCombiner::FoldXorWithConstants(BinaryOperator &I, Value *Op,
Value *A, Value *B, Value *C) {
ConstantInt *CI1 = dyn_cast<ConstantInt>(C);
if (!CI1)
return nullptr;
Value *V1 = nullptr;
ConstantInt *CI2 = nullptr;
if (!match(Op, m_And(m_Value(V1), m_ConstantInt(CI2))))
return nullptr;
APInt Xor = CI1->getValue() ^ CI2->getValue();
if (!Xor.isAllOnesValue())
return nullptr;
if (V1 == A || V1 == B) {
Value *NewOp = Builder->CreateAnd(V1 == A ? B : A, CI1);
return BinaryOperator::CreateXor(NewOp, V1);
}
return nullptr;
}
Instruction *InstCombiner::visitOr(BinaryOperator &I) {
bool Changed = SimplifyAssociativeOrCommutative(I);
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifyOrInst(Op0, Op1, DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
// (A&B)|(A&C) -> A&(B|C) etc
if (Value *V = SimplifyUsingDistributiveLaws(I))
return ReplaceInstUsesWith(I, V);
// See if we can simplify any instructions used by the instruction whose sole
// purpose is to compute bits we don't care about.
if (SimplifyDemandedInstructionBits(I))
return &I;
if (Value *V = SimplifyBSwap(I))
return ReplaceInstUsesWith(I, V);
if (ConstantInt *RHS = dyn_cast<ConstantInt>(Op1)) {
ConstantInt *C1 = nullptr; Value *X = nullptr;
// (X & C1) | C2 --> (X | C2) & (C1|C2)
// iff (C1 & C2) == 0.
if (match(Op0, m_And(m_Value(X), m_ConstantInt(C1))) &&
(RHS->getValue() & C1->getValue()) != 0 &&
Op0->hasOneUse()) {
Value *Or = Builder->CreateOr(X, RHS);
Or->takeName(Op0);
return BinaryOperator::CreateAnd(Or,
Builder->getInt(RHS->getValue() | C1->getValue()));
}
// (X ^ C1) | C2 --> (X | C2) ^ (C1&~C2)
if (match(Op0, m_Xor(m_Value(X), m_ConstantInt(C1))) &&
Op0->hasOneUse()) {
Value *Or = Builder->CreateOr(X, RHS);
Or->takeName(Op0);
return BinaryOperator::CreateXor(Or,
Builder->getInt(C1->getValue() & ~RHS->getValue()));
}
// Try to fold constant and into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (isa<PHINode>(Op0))
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
}
Value *A = nullptr, *B = nullptr;
ConstantInt *C1 = nullptr, *C2 = nullptr;
// (A | B) | C and A | (B | C) -> bswap if possible.
// (A >> B) | (C << D) and (A << B) | (B >> C) -> bswap if possible.
if (match(Op0, m_Or(m_Value(), m_Value())) ||
match(Op1, m_Or(m_Value(), m_Value())) ||
(match(Op0, m_LogicalShift(m_Value(), m_Value())) &&
match(Op1, m_LogicalShift(m_Value(), m_Value())))) {
if (Instruction *BSwap = MatchBSwap(I))
return BSwap;
}
// (X^C)|Y -> (X|Y)^C iff Y&C == 0
if (Op0->hasOneUse() &&
match(Op0, m_Xor(m_Value(A), m_ConstantInt(C1))) &&
MaskedValueIsZero(Op1, C1->getValue(), 0, &I)) {
Value *NOr = Builder->CreateOr(A, Op1);
NOr->takeName(Op0);
return BinaryOperator::CreateXor(NOr, C1);
}
// Y|(X^C) -> (X|Y)^C iff Y&C == 0
if (Op1->hasOneUse() &&
match(Op1, m_Xor(m_Value(A), m_ConstantInt(C1))) &&
MaskedValueIsZero(Op0, C1->getValue(), 0, &I)) {
Value *NOr = Builder->CreateOr(A, Op0);
NOr->takeName(Op0);
return BinaryOperator::CreateXor(NOr, C1);
}
// ((~A & B) | A) -> (A | B)
if (match(Op0, m_And(m_Not(m_Value(A)), m_Value(B))) &&
match(Op1, m_Specific(A)))
return BinaryOperator::CreateOr(A, B);
// ((A & B) | ~A) -> (~A | B)
if (match(Op0, m_And(m_Value(A), m_Value(B))) &&
match(Op1, m_Not(m_Specific(A))))
return BinaryOperator::CreateOr(Builder->CreateNot(A), B);
// (A & (~B)) | (A ^ B) -> (A ^ B)
if (match(Op0, m_And(m_Value(A), m_Not(m_Value(B)))) &&
match(Op1, m_Xor(m_Specific(A), m_Specific(B))))
return BinaryOperator::CreateXor(A, B);
// (A ^ B) | ( A & (~B)) -> (A ^ B)
if (match(Op0, m_Xor(m_Value(A), m_Value(B))) &&
match(Op1, m_And(m_Specific(A), m_Not(m_Specific(B)))))
return BinaryOperator::CreateXor(A, B);
// (A & C)|(B & D)
Value *C = nullptr, *D = nullptr;
if (match(Op0, m_And(m_Value(A), m_Value(C))) &&
match(Op1, m_And(m_Value(B), m_Value(D)))) {
Value *V1 = nullptr, *V2 = nullptr;
C1 = dyn_cast<ConstantInt>(C);
C2 = dyn_cast<ConstantInt>(D);
if (C1 && C2) { // (A & C1)|(B & C2)
if ((C1->getValue() & C2->getValue()) == 0) {
// ((V | N) & C1) | (V & C2) --> (V|N) & (C1|C2)
// iff (C1&C2) == 0 and (N&~C1) == 0
if (match(A, m_Or(m_Value(V1), m_Value(V2))) &&
((V1 == B &&
MaskedValueIsZero(V2, ~C1->getValue(), 0, &I)) || // (V|N)
(V2 == B &&
MaskedValueIsZero(V1, ~C1->getValue(), 0, &I)))) // (N|V)
return BinaryOperator::CreateAnd(A,
Builder->getInt(C1->getValue()|C2->getValue()));
// Or commutes, try both ways.
if (match(B, m_Or(m_Value(V1), m_Value(V2))) &&
((V1 == A &&
MaskedValueIsZero(V2, ~C2->getValue(), 0, &I)) || // (V|N)
(V2 == A &&
MaskedValueIsZero(V1, ~C2->getValue(), 0, &I)))) // (N|V)
return BinaryOperator::CreateAnd(B,
Builder->getInt(C1->getValue()|C2->getValue()));
// ((V|C3)&C1) | ((V|C4)&C2) --> (V|C3|C4)&(C1|C2)
// iff (C1&C2) == 0 and (C3&~C1) == 0 and (C4&~C2) == 0.
ConstantInt *C3 = nullptr, *C4 = nullptr;
if (match(A, m_Or(m_Value(V1), m_ConstantInt(C3))) &&
(C3->getValue() & ~C1->getValue()) == 0 &&
match(B, m_Or(m_Specific(V1), m_ConstantInt(C4))) &&
(C4->getValue() & ~C2->getValue()) == 0) {
V2 = Builder->CreateOr(V1, ConstantExpr::getOr(C3, C4), "bitfield");
return BinaryOperator::CreateAnd(V2,
Builder->getInt(C1->getValue()|C2->getValue()));
}
}
}
// (A & (C0?-1:0)) | (B & ~(C0?-1:0)) -> C0 ? A : B, and commuted variants.
// Don't do this for vector select idioms, the code generator doesn't handle
// them well yet.
if (!I.getType()->isVectorTy()) {
if (Instruction *Match = MatchSelectFromAndOr(A, B, C, D))
return Match;
if (Instruction *Match = MatchSelectFromAndOr(B, A, D, C))
return Match;
if (Instruction *Match = MatchSelectFromAndOr(C, B, A, D))
return Match;
if (Instruction *Match = MatchSelectFromAndOr(D, A, B, C))
return Match;
}
// ((A&~B)|(~A&B)) -> A^B
if ((match(C, m_Not(m_Specific(D))) &&
match(B, m_Not(m_Specific(A)))))
return BinaryOperator::CreateXor(A, D);
// ((~B&A)|(~A&B)) -> A^B
if ((match(A, m_Not(m_Specific(D))) &&
match(B, m_Not(m_Specific(C)))))
return BinaryOperator::CreateXor(C, D);
// ((A&~B)|(B&~A)) -> A^B
if ((match(C, m_Not(m_Specific(B))) &&
match(D, m_Not(m_Specific(A)))))
return BinaryOperator::CreateXor(A, B);
// ((~B&A)|(B&~A)) -> A^B
if ((match(A, m_Not(m_Specific(B))) &&
match(D, m_Not(m_Specific(C)))))
return BinaryOperator::CreateXor(C, B);
// ((A|B)&1)|(B&-2) -> (A&1) | B
if (match(A, m_Or(m_Value(V1), m_Specific(B))) ||
match(A, m_Or(m_Specific(B), m_Value(V1)))) {
Instruction *Ret = FoldOrWithConstants(I, Op1, V1, B, C);
if (Ret) return Ret;
}
// (B&-2)|((A|B)&1) -> (A&1) | B
if (match(B, m_Or(m_Specific(A), m_Value(V1))) ||
match(B, m_Or(m_Value(V1), m_Specific(A)))) {
Instruction *Ret = FoldOrWithConstants(I, Op0, A, V1, D);
if (Ret) return Ret;
}
// ((A^B)&1)|(B&-2) -> (A&1) ^ B
if (match(A, m_Xor(m_Value(V1), m_Specific(B))) ||
match(A, m_Xor(m_Specific(B), m_Value(V1)))) {
Instruction *Ret = FoldXorWithConstants(I, Op1, V1, B, C);
if (Ret) return Ret;
}
// (B&-2)|((A^B)&1) -> (A&1) ^ B
if (match(B, m_Xor(m_Specific(A), m_Value(V1))) ||
match(B, m_Xor(m_Value(V1), m_Specific(A)))) {
Instruction *Ret = FoldXorWithConstants(I, Op0, A, V1, D);
if (Ret) return Ret;
}
}
// (A ^ B) | ((B ^ C) ^ A) -> (A ^ B) | C
if (match(Op0, m_Xor(m_Value(A), m_Value(B))))
if (match(Op1, m_Xor(m_Xor(m_Specific(B), m_Value(C)), m_Specific(A))))
if (Op1->hasOneUse() || cast<BinaryOperator>(Op1)->hasOneUse())
return BinaryOperator::CreateOr(Op0, C);
// ((A ^ C) ^ B) | (B ^ A) -> (B ^ A) | C
if (match(Op0, m_Xor(m_Xor(m_Value(A), m_Value(C)), m_Value(B))))
if (match(Op1, m_Xor(m_Specific(B), m_Specific(A))))
if (Op0->hasOneUse() || cast<BinaryOperator>(Op0)->hasOneUse())
return BinaryOperator::CreateOr(Op1, C);
// ((B | C) & A) | B -> B | (A & C)
if (match(Op0, m_And(m_Or(m_Specific(Op1), m_Value(C)), m_Value(A))))
return BinaryOperator::CreateOr(Op1, Builder->CreateAnd(A, C));
// (~A | ~B) == (~(A & B)) - De Morgan's Law
if (Value *Op0NotVal = dyn_castNotVal(Op0))
if (Value *Op1NotVal = dyn_castNotVal(Op1))
if (Op0->hasOneUse() && Op1->hasOneUse()) {
Value *And = Builder->CreateAnd(Op0NotVal, Op1NotVal,
I.getName()+".demorgan");
return BinaryOperator::CreateNot(And);
}
// Canonicalize xor to the RHS.
bool SwappedForXor = false;
if (match(Op0, m_Xor(m_Value(), m_Value()))) {
std::swap(Op0, Op1);
SwappedForXor = true;
}
// A | ( A ^ B) -> A | B
// A | (~A ^ B) -> A | ~B
// (A & B) | (A ^ B)
if (match(Op1, m_Xor(m_Value(A), m_Value(B)))) {
if (Op0 == A || Op0 == B)
return BinaryOperator::CreateOr(A, B);
if (match(Op0, m_And(m_Specific(A), m_Specific(B))) ||
match(Op0, m_And(m_Specific(B), m_Specific(A))))
return BinaryOperator::CreateOr(A, B);
if (Op1->hasOneUse() && match(A, m_Not(m_Specific(Op0)))) {
Value *Not = Builder->CreateNot(B, B->getName()+".not");
return BinaryOperator::CreateOr(Not, Op0);
}
if (Op1->hasOneUse() && match(B, m_Not(m_Specific(Op0)))) {
Value *Not = Builder->CreateNot(A, A->getName()+".not");
return BinaryOperator::CreateOr(Not, Op0);
}
}
// A | ~(A | B) -> A | ~B
// A | ~(A ^ B) -> A | ~B
if (match(Op1, m_Not(m_Value(A))))
if (BinaryOperator *B = dyn_cast<BinaryOperator>(A))
if ((Op0 == B->getOperand(0) || Op0 == B->getOperand(1)) &&
Op1->hasOneUse() && (B->getOpcode() == Instruction::Or ||
B->getOpcode() == Instruction::Xor)) {
Value *NotOp = Op0 == B->getOperand(0) ? B->getOperand(1) :
B->getOperand(0);
Value *Not = Builder->CreateNot(NotOp, NotOp->getName()+".not");
return BinaryOperator::CreateOr(Not, Op0);
}
// (A & B) | ((~A) ^ B) -> (~A ^ B)
if (match(Op0, m_And(m_Value(A), m_Value(B))) &&
match(Op1, m_Xor(m_Not(m_Specific(A)), m_Specific(B))))
return BinaryOperator::CreateXor(Builder->CreateNot(A), B);
// ((~A) ^ B) | (A & B) -> (~A ^ B)
if (match(Op0, m_Xor(m_Not(m_Value(A)), m_Value(B))) &&
match(Op1, m_And(m_Specific(A), m_Specific(B))))
return BinaryOperator::CreateXor(Builder->CreateNot(A), B);
if (SwappedForXor)
std::swap(Op0, Op1);
{
ICmpInst *LHS = dyn_cast<ICmpInst>(Op0);
ICmpInst *RHS = dyn_cast<ICmpInst>(Op1);
if (LHS && RHS)
if (Value *Res = FoldOrOfICmps(LHS, RHS, &I))
return ReplaceInstUsesWith(I, Res);
// TODO: Make this recursive; it's a little tricky because an arbitrary
// number of 'or' instructions might have to be created.
Value *X, *Y;
if (LHS && match(Op1, m_OneUse(m_Or(m_Value(X), m_Value(Y))))) {
if (auto *Cmp = dyn_cast<ICmpInst>(X))
if (Value *Res = FoldOrOfICmps(LHS, Cmp, &I))
return ReplaceInstUsesWith(I, Builder->CreateOr(Res, Y));
if (auto *Cmp = dyn_cast<ICmpInst>(Y))
if (Value *Res = FoldOrOfICmps(LHS, Cmp, &I))
return ReplaceInstUsesWith(I, Builder->CreateOr(Res, X));
}
if (RHS && match(Op0, m_OneUse(m_Or(m_Value(X), m_Value(Y))))) {
if (auto *Cmp = dyn_cast<ICmpInst>(X))
if (Value *Res = FoldOrOfICmps(Cmp, RHS, &I))
return ReplaceInstUsesWith(I, Builder->CreateOr(Res, Y));
if (auto *Cmp = dyn_cast<ICmpInst>(Y))
if (Value *Res = FoldOrOfICmps(Cmp, RHS, &I))
return ReplaceInstUsesWith(I, Builder->CreateOr(Res, X));
}
}
// (fcmp uno x, c) | (fcmp uno y, c) -> (fcmp uno x, y)
if (FCmpInst *LHS = dyn_cast<FCmpInst>(I.getOperand(0)))
if (FCmpInst *RHS = dyn_cast<FCmpInst>(I.getOperand(1)))
if (Value *Res = FoldOrOfFCmps(LHS, RHS))
return ReplaceInstUsesWith(I, Res);
// fold (or (cast A), (cast B)) -> (cast (or A, B))
if (CastInst *Op0C = dyn_cast<CastInst>(Op0)) {
CastInst *Op1C = dyn_cast<CastInst>(Op1);
if (Op1C && Op0C->getOpcode() == Op1C->getOpcode()) {// same cast kind ?
Type *SrcTy = Op0C->getOperand(0)->getType();
if (SrcTy == Op1C->getOperand(0)->getType() &&
SrcTy->isIntOrIntVectorTy()) {
Value *Op0COp = Op0C->getOperand(0), *Op1COp = Op1C->getOperand(0);
if ((!isa<ICmpInst>(Op0COp) || !isa<ICmpInst>(Op1COp)) &&
// Only do this if the casts both really cause code to be
// generated.
ShouldOptimizeCast(Op0C->getOpcode(), Op0COp, I.getType()) &&
ShouldOptimizeCast(Op1C->getOpcode(), Op1COp, I.getType())) {
Value *NewOp = Builder->CreateOr(Op0COp, Op1COp, I.getName());
return CastInst::Create(Op0C->getOpcode(), NewOp, I.getType());
}
// If this is or(cast(icmp), cast(icmp)), try to fold this even if the
// cast is otherwise not optimizable. This happens for vector sexts.
if (ICmpInst *RHS = dyn_cast<ICmpInst>(Op1COp))
if (ICmpInst *LHS = dyn_cast<ICmpInst>(Op0COp))
if (Value *Res = FoldOrOfICmps(LHS, RHS, &I))
return CastInst::Create(Op0C->getOpcode(), Res, I.getType());
// If this is or(cast(fcmp), cast(fcmp)), try to fold this even if the
// cast is otherwise not optimizable. This happens for vector sexts.
if (FCmpInst *RHS = dyn_cast<FCmpInst>(Op1COp))
if (FCmpInst *LHS = dyn_cast<FCmpInst>(Op0COp))
if (Value *Res = FoldOrOfFCmps(LHS, RHS))
return CastInst::Create(Op0C->getOpcode(), Res, I.getType());
}
}
}
// or(sext(A), B) -> A ? -1 : B where A is an i1
// or(A, sext(B)) -> B ? -1 : A where B is an i1
if (match(Op0, m_SExt(m_Value(A))) && A->getType()->isIntegerTy(1))
return SelectInst::Create(A, ConstantInt::getSigned(I.getType(), -1), Op1);
if (match(Op1, m_SExt(m_Value(A))) && A->getType()->isIntegerTy(1))
return SelectInst::Create(A, ConstantInt::getSigned(I.getType(), -1), Op0);
// Note: If we've gotten to the point of visiting the outer OR, then the
// inner one couldn't be simplified. If it was a constant, then it won't
// be simplified by a later pass either, so we try swapping the inner/outer
// ORs in the hopes that we'll be able to simplify it this way.
// (X|C) | V --> (X|V) | C
if (Op0->hasOneUse() && !isa<ConstantInt>(Op1) &&
match(Op0, m_Or(m_Value(A), m_ConstantInt(C1)))) {
Value *Inner = Builder->CreateOr(A, Op1);
Inner->takeName(Op0);
return BinaryOperator::CreateOr(Inner, C1);
}
// Change (or (bool?A:B),(bool?C:D)) --> (bool?(or A,C):(or B,D))
// Since this OR statement hasn't been optimized further yet, we hope
// that this transformation will allow the new ORs to be optimized.
{
Value *X = nullptr, *Y = nullptr;
if (Op0->hasOneUse() && Op1->hasOneUse() &&
match(Op0, m_Select(m_Value(X), m_Value(A), m_Value(B))) &&
match(Op1, m_Select(m_Value(Y), m_Value(C), m_Value(D))) && X == Y) {
Value *orTrue = Builder->CreateOr(A, C);
Value *orFalse = Builder->CreateOr(B, D);
return SelectInst::Create(X, orTrue, orFalse);
}
}
return Changed ? &I : nullptr;
}
Instruction *InstCombiner::visitXor(BinaryOperator &I) {
bool Changed = SimplifyAssociativeOrCommutative(I);
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifyXorInst(Op0, Op1, DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
// (A&B)^(A&C) -> A&(B^C) etc
if (Value *V = SimplifyUsingDistributiveLaws(I))
return ReplaceInstUsesWith(I, V);
// See if we can simplify any instructions used by the instruction whose sole
// purpose is to compute bits we don't care about.
if (SimplifyDemandedInstructionBits(I))
return &I;
if (Value *V = SimplifyBSwap(I))
return ReplaceInstUsesWith(I, V);
// Is this a ~ operation?
if (Value *NotOp = dyn_castNotVal(&I)) {
if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(NotOp)) {
if (Op0I->getOpcode() == Instruction::And ||
Op0I->getOpcode() == Instruction::Or) {
// ~(~X & Y) --> (X | ~Y) - De Morgan's Law
// ~(~X | Y) === (X & ~Y) - De Morgan's Law
if (dyn_castNotVal(Op0I->getOperand(1)))
Op0I->swapOperands();
if (Value *Op0NotVal = dyn_castNotVal(Op0I->getOperand(0))) {
Value *NotY =
Builder->CreateNot(Op0I->getOperand(1),
Op0I->getOperand(1)->getName()+".not");
if (Op0I->getOpcode() == Instruction::And)
return BinaryOperator::CreateOr(Op0NotVal, NotY);
return BinaryOperator::CreateAnd(Op0NotVal, NotY);
}
// ~(X & Y) --> (~X | ~Y) - De Morgan's Law
// ~(X | Y) === (~X & ~Y) - De Morgan's Law
if (IsFreeToInvert(Op0I->getOperand(0),
Op0I->getOperand(0)->hasOneUse()) &&
IsFreeToInvert(Op0I->getOperand(1),
Op0I->getOperand(1)->hasOneUse())) {
Value *NotX =
Builder->CreateNot(Op0I->getOperand(0), "notlhs");
Value *NotY =
Builder->CreateNot(Op0I->getOperand(1), "notrhs");
if (Op0I->getOpcode() == Instruction::And)
return BinaryOperator::CreateOr(NotX, NotY);
return BinaryOperator::CreateAnd(NotX, NotY);
}
} else if (Op0I->getOpcode() == Instruction::AShr) {
// ~(~X >>s Y) --> (X >>s Y)
if (Value *Op0NotVal = dyn_castNotVal(Op0I->getOperand(0)))
return BinaryOperator::CreateAShr(Op0NotVal, Op0I->getOperand(1));
}
}
}
if (Constant *RHS = dyn_cast<Constant>(Op1)) {
if (RHS->isAllOnesValue() && Op0->hasOneUse())
// xor (cmp A, B), true = not (cmp A, B) = !cmp A, B
if (CmpInst *CI = dyn_cast<CmpInst>(Op0))
return CmpInst::Create(CI->getOpcode(),
CI->getInversePredicate(),
CI->getOperand(0), CI->getOperand(1));
}
if (ConstantInt *RHS = dyn_cast<ConstantInt>(Op1)) {
// fold (xor(zext(cmp)), 1) and (xor(sext(cmp)), -1) to ext(!cmp).
if (CastInst *Op0C = dyn_cast<CastInst>(Op0)) {
if (CmpInst *CI = dyn_cast<CmpInst>(Op0C->getOperand(0))) {
if (CI->hasOneUse() && Op0C->hasOneUse()) {
Instruction::CastOps Opcode = Op0C->getOpcode();
if ((Opcode == Instruction::ZExt || Opcode == Instruction::SExt) &&
(RHS == ConstantExpr::getCast(Opcode, Builder->getTrue(),
Op0C->getDestTy()))) {
CI->setPredicate(CI->getInversePredicate());
return CastInst::Create(Opcode, CI, Op0C->getType());
}
}
}
}
if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0)) {
// ~(c-X) == X-c-1 == X+(-c-1)
if (Op0I->getOpcode() == Instruction::Sub && RHS->isAllOnesValue())
if (Constant *Op0I0C = dyn_cast<Constant>(Op0I->getOperand(0))) {
Constant *NegOp0I0C = ConstantExpr::getNeg(Op0I0C);
Constant *ConstantRHS = ConstantExpr::getSub(NegOp0I0C,
ConstantInt::get(I.getType(), 1));
return BinaryOperator::CreateAdd(Op0I->getOperand(1), ConstantRHS);
}
if (ConstantInt *Op0CI = dyn_cast<ConstantInt>(Op0I->getOperand(1))) {
if (Op0I->getOpcode() == Instruction::Add) {
// ~(X-c) --> (-c-1)-X
if (RHS->isAllOnesValue()) {
Constant *NegOp0CI = ConstantExpr::getNeg(Op0CI);
return BinaryOperator::CreateSub(
ConstantExpr::getSub(NegOp0CI,
ConstantInt::get(I.getType(), 1)),
Op0I->getOperand(0));
} else if (RHS->getValue().isSignBit()) {
// (X + C) ^ signbit -> (X + C + signbit)
Constant *C = Builder->getInt(RHS->getValue() + Op0CI->getValue());
return BinaryOperator::CreateAdd(Op0I->getOperand(0), C);
}
} else if (Op0I->getOpcode() == Instruction::Or) {
// (X|C1)^C2 -> X^(C1|C2) iff X&~C1 == 0
if (MaskedValueIsZero(Op0I->getOperand(0), Op0CI->getValue(),
0, &I)) {
Constant *NewRHS = ConstantExpr::getOr(Op0CI, RHS);
// Anything in both C1 and C2 is known to be zero, remove it from
// NewRHS.
Constant *CommonBits = ConstantExpr::getAnd(Op0CI, RHS);
NewRHS = ConstantExpr::getAnd(NewRHS,
ConstantExpr::getNot(CommonBits));
Worklist.Add(Op0I);
I.setOperand(0, Op0I->getOperand(0));
I.setOperand(1, NewRHS);
return &I;
}
} else if (Op0I->getOpcode() == Instruction::LShr) {
// ((X^C1) >> C2) ^ C3 -> (X>>C2) ^ ((C1>>C2)^C3)
// E1 = "X ^ C1"
BinaryOperator *E1;
ConstantInt *C1;
if (Op0I->hasOneUse() &&
(E1 = dyn_cast<BinaryOperator>(Op0I->getOperand(0))) &&
E1->getOpcode() == Instruction::Xor &&
(C1 = dyn_cast<ConstantInt>(E1->getOperand(1)))) {
// fold (C1 >> C2) ^ C3
ConstantInt *C2 = Op0CI, *C3 = RHS;
APInt FoldConst = C1->getValue().lshr(C2->getValue());
FoldConst ^= C3->getValue();
// Prepare the two operands.
Value *Opnd0 = Builder->CreateLShr(E1->getOperand(0), C2);
Opnd0->takeName(Op0I);
cast<Instruction>(Opnd0)->setDebugLoc(I.getDebugLoc());
Value *FoldVal = ConstantInt::get(Opnd0->getType(), FoldConst);
return BinaryOperator::CreateXor(Opnd0, FoldVal);
}
}
}
}
// Try to fold constant and into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (isa<PHINode>(Op0))
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
}
BinaryOperator *Op1I = dyn_cast<BinaryOperator>(Op1);
if (Op1I) {
Value *A, *B;
if (match(Op1I, m_Or(m_Value(A), m_Value(B)))) {
if (A == Op0) { // B^(B|A) == (A|B)^B
Op1I->swapOperands();
I.swapOperands();
std::swap(Op0, Op1);
} else if (B == Op0) { // B^(A|B) == (A|B)^B
I.swapOperands(); // Simplified below.
std::swap(Op0, Op1);
}
} else if (match(Op1I, m_And(m_Value(A), m_Value(B))) &&
Op1I->hasOneUse()){
if (A == Op0) { // A^(A&B) -> A^(B&A)
Op1I->swapOperands();
std::swap(A, B);
}
if (B == Op0) { // A^(B&A) -> (B&A)^A
I.swapOperands(); // Simplified below.
std::swap(Op0, Op1);
}
}
}
BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0);
if (Op0I) {
Value *A, *B;
if (match(Op0I, m_Or(m_Value(A), m_Value(B))) &&
Op0I->hasOneUse()) {
if (A == Op1) // (B|A)^B == (A|B)^B
std::swap(A, B);
if (B == Op1) // (A|B)^B == A & ~B
return BinaryOperator::CreateAnd(A, Builder->CreateNot(Op1));
} else if (match(Op0I, m_And(m_Value(A), m_Value(B))) &&
Op0I->hasOneUse()){
if (A == Op1) // (A&B)^A -> (B&A)^A
std::swap(A, B);
if (B == Op1 && // (B&A)^A == ~B & A
!isa<ConstantInt>(Op1)) { // Canonical form is (B&C)^C
return BinaryOperator::CreateAnd(Builder->CreateNot(A), Op1);
}
}
}
if (Op0I && Op1I) {
Value *A, *B, *C, *D;
// (A & B)^(A | B) -> A ^ B
if (match(Op0I, m_And(m_Value(A), m_Value(B))) &&
match(Op1I, m_Or(m_Value(C), m_Value(D)))) {
if ((A == C && B == D) || (A == D && B == C))
return BinaryOperator::CreateXor(A, B);
}
// (A | B)^(A & B) -> A ^ B
if (match(Op0I, m_Or(m_Value(A), m_Value(B))) &&
match(Op1I, m_And(m_Value(C), m_Value(D)))) {
if ((A == C && B == D) || (A == D && B == C))
return BinaryOperator::CreateXor(A, B);
}
// (A | ~B) ^ (~A | B) -> A ^ B
if (match(Op0I, m_Or(m_Value(A), m_Not(m_Value(B)))) &&
match(Op1I, m_Or(m_Not(m_Specific(A)), m_Specific(B)))) {
return BinaryOperator::CreateXor(A, B);
}
// (~A | B) ^ (A | ~B) -> A ^ B
if (match(Op0I, m_Or(m_Not(m_Value(A)), m_Value(B))) &&
match(Op1I, m_Or(m_Specific(A), m_Not(m_Specific(B))))) {
return BinaryOperator::CreateXor(A, B);
}
// (A & ~B) ^ (~A & B) -> A ^ B
if (match(Op0I, m_And(m_Value(A), m_Not(m_Value(B)))) &&
match(Op1I, m_And(m_Not(m_Specific(A)), m_Specific(B)))) {
return BinaryOperator::CreateXor(A, B);
}
// (~A & B) ^ (A & ~B) -> A ^ B
if (match(Op0I, m_And(m_Not(m_Value(A)), m_Value(B))) &&
match(Op1I, m_And(m_Specific(A), m_Not(m_Specific(B))))) {
return BinaryOperator::CreateXor(A, B);
}
// (A ^ C)^(A | B) -> ((~A) & B) ^ C
if (match(Op0I, m_Xor(m_Value(D), m_Value(C))) &&
match(Op1I, m_Or(m_Value(A), m_Value(B)))) {
if (D == A)
return BinaryOperator::CreateXor(
Builder->CreateAnd(Builder->CreateNot(A), B), C);
if (D == B)
return BinaryOperator::CreateXor(
Builder->CreateAnd(Builder->CreateNot(B), A), C);
}
// (A | B)^(A ^ C) -> ((~A) & B) ^ C
if (match(Op0I, m_Or(m_Value(A), m_Value(B))) &&
match(Op1I, m_Xor(m_Value(D), m_Value(C)))) {
if (D == A)
return BinaryOperator::CreateXor(
Builder->CreateAnd(Builder->CreateNot(A), B), C);
if (D == B)
return BinaryOperator::CreateXor(
Builder->CreateAnd(Builder->CreateNot(B), A), C);
}
// (A & B) ^ (A ^ B) -> (A | B)
if (match(Op0I, m_And(m_Value(A), m_Value(B))) &&
match(Op1I, m_Xor(m_Specific(A), m_Specific(B))))
return BinaryOperator::CreateOr(A, B);
// (A ^ B) ^ (A & B) -> (A | B)
if (match(Op0I, m_Xor(m_Value(A), m_Value(B))) &&
match(Op1I, m_And(m_Specific(A), m_Specific(B))))
return BinaryOperator::CreateOr(A, B);
}
Value *A = nullptr, *B = nullptr;
// (A & ~B) ^ (~A) -> ~(A & B)
if (match(Op0, m_And(m_Value(A), m_Not(m_Value(B)))) &&
match(Op1, m_Not(m_Specific(A))))
return BinaryOperator::CreateNot(Builder->CreateAnd(A, B));
// (icmp1 A, B) ^ (icmp2 A, B) --> (icmp3 A, B)
if (ICmpInst *RHS = dyn_cast<ICmpInst>(I.getOperand(1)))
if (ICmpInst *LHS = dyn_cast<ICmpInst>(I.getOperand(0)))
if (PredicatesFoldable(LHS->getPredicate(), RHS->getPredicate())) {
if (LHS->getOperand(0) == RHS->getOperand(1) &&
LHS->getOperand(1) == RHS->getOperand(0))
LHS->swapOperands();
if (LHS->getOperand(0) == RHS->getOperand(0) &&
LHS->getOperand(1) == RHS->getOperand(1)) {
Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
unsigned Code = getICmpCode(LHS) ^ getICmpCode(RHS);
bool isSigned = LHS->isSigned() || RHS->isSigned();
return ReplaceInstUsesWith(I,
getNewICmpValue(isSigned, Code, Op0, Op1,
Builder));
}
}
// fold (xor (cast A), (cast B)) -> (cast (xor A, B))
if (CastInst *Op0C = dyn_cast<CastInst>(Op0)) {
if (CastInst *Op1C = dyn_cast<CastInst>(Op1))
if (Op0C->getOpcode() == Op1C->getOpcode()) { // same cast kind?
Type *SrcTy = Op0C->getOperand(0)->getType();
if (SrcTy == Op1C->getOperand(0)->getType() && SrcTy->isIntegerTy() &&
// Only do this if the casts both really cause code to be generated.
ShouldOptimizeCast(Op0C->getOpcode(), Op0C->getOperand(0),
I.getType()) &&
ShouldOptimizeCast(Op1C->getOpcode(), Op1C->getOperand(0),
I.getType())) {
Value *NewOp = Builder->CreateXor(Op0C->getOperand(0),
Op1C->getOperand(0), I.getName());
return CastInst::Create(Op0C->getOpcode(), NewOp, I.getType());
}
}
}
return Changed ? &I : nullptr;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/InstCombineCalls.cpp | //===- InstCombineCalls.cpp -----------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the visitCall and visitInvoke functions.
//
//===----------------------------------------------------------------------===//
#include "InstCombineInternal.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/IR/Statepoint.h"
#include "llvm/Transforms/Utils/BuildLibCalls.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/SimplifyLibCalls.h"
using namespace llvm;
using namespace PatternMatch;
#define DEBUG_TYPE "instcombine"
STATISTIC(NumSimplified, "Number of library calls simplified");
/// getPromotedType - Return the specified type promoted as it would be to pass
/// though a va_arg area.
static Type *getPromotedType(Type *Ty) {
if (IntegerType* ITy = dyn_cast<IntegerType>(Ty)) {
if (ITy->getBitWidth() < 32)
return Type::getInt32Ty(Ty->getContext());
}
return Ty;
}
/// reduceToSingleValueType - Given an aggregate type which ultimately holds a
/// single scalar element, like {{{type}}} or [1 x type], return type.
static Type *reduceToSingleValueType(Type *T) {
while (!T->isSingleValueType()) {
if (StructType *STy = dyn_cast<StructType>(T)) {
if (STy->getNumElements() == 1)
T = STy->getElementType(0);
else
break;
} else if (ArrayType *ATy = dyn_cast<ArrayType>(T)) {
if (ATy->getNumElements() == 1)
T = ATy->getElementType();
else
break;
} else
break;
}
return T;
}
Instruction *InstCombiner::SimplifyMemTransfer(MemIntrinsic *MI) {
unsigned DstAlign = getKnownAlignment(MI->getArgOperand(0), DL, MI, AC, DT);
unsigned SrcAlign = getKnownAlignment(MI->getArgOperand(1), DL, MI, AC, DT);
unsigned MinAlign = std::min(DstAlign, SrcAlign);
unsigned CopyAlign = MI->getAlignment();
if (CopyAlign < MinAlign) {
MI->setAlignment(ConstantInt::get(MI->getAlignmentType(),
MinAlign, false));
return MI;
}
// If MemCpyInst length is 1/2/4/8 bytes then replace memcpy with
// load/store.
ConstantInt *MemOpLength = dyn_cast<ConstantInt>(MI->getArgOperand(2));
if (!MemOpLength) return nullptr;
// Source and destination pointer types are always "i8*" for intrinsic. See
// if the size is something we can handle with a single primitive load/store.
// A single load+store correctly handles overlapping memory in the memmove
// case.
uint64_t Size = MemOpLength->getLimitedValue();
assert(Size && "0-sized memory transferring should be removed already.");
if (Size > 8 || (Size&(Size-1)))
return nullptr; // If not 1/2/4/8 bytes, exit.
// Use an integer load+store unless we can find something better.
unsigned SrcAddrSp =
cast<PointerType>(MI->getArgOperand(1)->getType())->getAddressSpace();
unsigned DstAddrSp =
cast<PointerType>(MI->getArgOperand(0)->getType())->getAddressSpace();
IntegerType* IntType = IntegerType::get(MI->getContext(), Size<<3);
Type *NewSrcPtrTy = PointerType::get(IntType, SrcAddrSp);
Type *NewDstPtrTy = PointerType::get(IntType, DstAddrSp);
// Memcpy forces the use of i8* for the source and destination. That means
// that if you're using memcpy to move one double around, you'll get a cast
// from double* to i8*. We'd much rather use a double load+store rather than
// an i64 load+store, here because this improves the odds that the source or
// dest address will be promotable. See if we can find a better type than the
// integer datatype.
Value *StrippedDest = MI->getArgOperand(0)->stripPointerCasts();
MDNode *CopyMD = nullptr;
if (StrippedDest != MI->getArgOperand(0)) {
Type *SrcETy = cast<PointerType>(StrippedDest->getType())
->getElementType();
if (SrcETy->isSized() && DL.getTypeStoreSize(SrcETy) == Size) {
// The SrcETy might be something like {{{double}}} or [1 x double]. Rip
// down through these levels if so.
SrcETy = reduceToSingleValueType(SrcETy);
if (SrcETy->isSingleValueType()) {
NewSrcPtrTy = PointerType::get(SrcETy, SrcAddrSp);
NewDstPtrTy = PointerType::get(SrcETy, DstAddrSp);
// If the memcpy has metadata describing the members, see if we can
// get the TBAA tag describing our copy.
if (MDNode *M = MI->getMetadata(LLVMContext::MD_tbaa_struct)) {
if (M->getNumOperands() == 3 && M->getOperand(0) &&
mdconst::hasa<ConstantInt>(M->getOperand(0)) &&
mdconst::extract<ConstantInt>(M->getOperand(0))->isNullValue() &&
M->getOperand(1) &&
mdconst::hasa<ConstantInt>(M->getOperand(1)) &&
mdconst::extract<ConstantInt>(M->getOperand(1))->getValue() ==
Size &&
M->getOperand(2) && isa<MDNode>(M->getOperand(2)))
CopyMD = cast<MDNode>(M->getOperand(2));
}
}
}
}
// If the memcpy/memmove provides better alignment info than we can
// infer, use it.
SrcAlign = std::max(SrcAlign, CopyAlign);
DstAlign = std::max(DstAlign, CopyAlign);
Value *Src = Builder->CreateBitCast(MI->getArgOperand(1), NewSrcPtrTy);
Value *Dest = Builder->CreateBitCast(MI->getArgOperand(0), NewDstPtrTy);
LoadInst *L = Builder->CreateLoad(Src, MI->isVolatile());
L->setAlignment(SrcAlign);
if (CopyMD)
L->setMetadata(LLVMContext::MD_tbaa, CopyMD);
StoreInst *S = Builder->CreateStore(L, Dest, MI->isVolatile());
S->setAlignment(DstAlign);
if (CopyMD)
S->setMetadata(LLVMContext::MD_tbaa, CopyMD);
// Set the size of the copy to 0, it will be deleted on the next iteration.
MI->setArgOperand(2, Constant::getNullValue(MemOpLength->getType()));
return MI;
}
Instruction *InstCombiner::SimplifyMemSet(MemSetInst *MI) {
unsigned Alignment = getKnownAlignment(MI->getDest(), DL, MI, AC, DT);
if (MI->getAlignment() < Alignment) {
MI->setAlignment(ConstantInt::get(MI->getAlignmentType(),
Alignment, false));
return MI;
}
// Extract the length and alignment and fill if they are constant.
ConstantInt *LenC = dyn_cast<ConstantInt>(MI->getLength());
ConstantInt *FillC = dyn_cast<ConstantInt>(MI->getValue());
if (!LenC || !FillC || !FillC->getType()->isIntegerTy(8))
return nullptr;
uint64_t Len = LenC->getLimitedValue();
Alignment = MI->getAlignment();
assert(Len && "0-sized memory setting should be removed already.");
// memset(s,c,n) -> store s, c (for n=1,2,4,8)
if (Len <= 8 && isPowerOf2_32((uint32_t)Len)) {
Type *ITy = IntegerType::get(MI->getContext(), Len*8); // n=1 -> i8.
Value *Dest = MI->getDest();
unsigned DstAddrSp = cast<PointerType>(Dest->getType())->getAddressSpace();
Type *NewDstPtrTy = PointerType::get(ITy, DstAddrSp);
Dest = Builder->CreateBitCast(Dest, NewDstPtrTy);
// Alignment 0 is identity for alignment 1 for memset, but not store.
if (Alignment == 0) Alignment = 1;
// Extract the fill value and store.
uint64_t Fill = FillC->getZExtValue()*0x0101010101010101ULL;
StoreInst *S = Builder->CreateStore(ConstantInt::get(ITy, Fill), Dest,
MI->isVolatile());
S->setAlignment(Alignment);
// Set the size of the copy to 0, it will be deleted on the next iteration.
MI->setLength(Constant::getNullValue(LenC->getType()));
return MI;
}
return nullptr;
}
#if 0 // HLSL Change - remove platform intrinsics
static Value *SimplifyX86insertps(const IntrinsicInst &II,
InstCombiner::BuilderTy &Builder) {
if (auto *CInt = dyn_cast<ConstantInt>(II.getArgOperand(2))) {
VectorType *VecTy = cast<VectorType>(II.getType());
assert(VecTy->getNumElements() == 4 && "insertps with wrong vector type");
// The immediate permute control byte looks like this:
// [3:0] - zero mask for each 32-bit lane
// [5:4] - select one 32-bit destination lane
// [7:6] - select one 32-bit source lane
uint8_t Imm = CInt->getZExtValue();
uint8_t ZMask = Imm & 0xf;
uint8_t DestLane = (Imm >> 4) & 0x3;
uint8_t SourceLane = (Imm >> 6) & 0x3;
ConstantAggregateZero *ZeroVector = ConstantAggregateZero::get(VecTy);
// If all zero mask bits are set, this was just a weird way to
// generate a zero vector.
if (ZMask == 0xf)
return ZeroVector;
// Initialize by passing all of the first source bits through.
int ShuffleMask[4] = { 0, 1, 2, 3 };
// We may replace the second operand with the zero vector.
Value *V1 = II.getArgOperand(1);
if (ZMask) {
// If the zero mask is being used with a single input or the zero mask
// overrides the destination lane, this is a shuffle with the zero vector.
if ((II.getArgOperand(0) == II.getArgOperand(1)) ||
(ZMask & (1 << DestLane))) {
V1 = ZeroVector;
// We may still move 32-bits of the first source vector from one lane
// to another.
ShuffleMask[DestLane] = SourceLane;
// The zero mask may override the previous insert operation.
for (unsigned i = 0; i < 4; ++i)
if ((ZMask >> i) & 0x1)
ShuffleMask[i] = i + 4;
} else {
// TODO: Model this case as 2 shuffles or a 'logical and' plus shuffle?
return nullptr;
}
} else {
// Replace the selected destination lane with the selected source lane.
ShuffleMask[DestLane] = SourceLane + 4;
}
return Builder.CreateShuffleVector(II.getArgOperand(0), V1, ShuffleMask);
}
return nullptr;
}
/// The shuffle mask for a perm2*128 selects any two halves of two 256-bit
/// source vectors, unless a zero bit is set. If a zero bit is set,
/// then ignore that half of the mask and clear that half of the vector.
static Value *SimplifyX86vperm2(const IntrinsicInst &II,
InstCombiner::BuilderTy &Builder) {
if (auto *CInt = dyn_cast<ConstantInt>(II.getArgOperand(2))) {
VectorType *VecTy = cast<VectorType>(II.getType());
ConstantAggregateZero *ZeroVector = ConstantAggregateZero::get(VecTy);
// The immediate permute control byte looks like this:
// [1:0] - select 128 bits from sources for low half of destination
// [2] - ignore
// [3] - zero low half of destination
// [5:4] - select 128 bits from sources for high half of destination
// [6] - ignore
// [7] - zero high half of destination
uint8_t Imm = CInt->getZExtValue();
bool LowHalfZero = Imm & 0x08;
bool HighHalfZero = Imm & 0x80;
// If both zero mask bits are set, this was just a weird way to
// generate a zero vector.
if (LowHalfZero && HighHalfZero)
return ZeroVector;
// If 0 or 1 zero mask bits are set, this is a simple shuffle.
unsigned NumElts = VecTy->getNumElements();
unsigned HalfSize = NumElts / 2;
SmallVector<int, 8> ShuffleMask(NumElts);
// The high bit of the selection field chooses the 1st or 2nd operand.
bool LowInputSelect = Imm & 0x02;
bool HighInputSelect = Imm & 0x20;
// The low bit of the selection field chooses the low or high half
// of the selected operand.
bool LowHalfSelect = Imm & 0x01;
bool HighHalfSelect = Imm & 0x10;
// Determine which operand(s) are actually in use for this instruction.
Value *V0 = LowInputSelect ? II.getArgOperand(1) : II.getArgOperand(0);
Value *V1 = HighInputSelect ? II.getArgOperand(1) : II.getArgOperand(0);
// If needed, replace operands based on zero mask.
V0 = LowHalfZero ? ZeroVector : V0;
V1 = HighHalfZero ? ZeroVector : V1;
// Permute low half of result.
unsigned StartIndex = LowHalfSelect ? HalfSize : 0;
for (unsigned i = 0; i < HalfSize; ++i)
ShuffleMask[i] = StartIndex + i;
// Permute high half of result.
StartIndex = HighHalfSelect ? HalfSize : 0;
StartIndex += NumElts;
for (unsigned i = 0; i < HalfSize; ++i)
ShuffleMask[i + HalfSize] = StartIndex + i;
return Builder.CreateShuffleVector(V0, V1, ShuffleMask);
}
return nullptr;
}
#endif // HLSL Change - remove platform intrinsics
/// visitCallInst - CallInst simplification. This mostly only handles folding
/// of intrinsic instructions. For normal calls, it allows visitCallSite to do
/// the heavy lifting.
///
Instruction *InstCombiner::visitCallInst(CallInst &CI) {
auto Args = CI.arg_operands();
if (Value *V = SimplifyCall(CI.getCalledValue(), Args.begin(), Args.end(), DL,
TLI, DT, AC))
return ReplaceInstUsesWith(CI, V);
if (isFreeCall(&CI, TLI))
return visitFree(CI);
// If the caller function is nounwind, mark the call as nounwind, even if the
// callee isn't.
if (CI.getParent()->getParent()->doesNotThrow() &&
!CI.doesNotThrow()) {
CI.setDoesNotThrow();
return &CI;
}
IntrinsicInst *II = dyn_cast<IntrinsicInst>(&CI);
if (!II) return visitCallSite(&CI);
// Intrinsics cannot occur in an invoke, so handle them here instead of in
// visitCallSite.
if (MemIntrinsic *MI = dyn_cast<MemIntrinsic>(II)) {
bool Changed = false;
// memmove/cpy/set of zero bytes is a noop.
if (Constant *NumBytes = dyn_cast<Constant>(MI->getLength())) {
if (NumBytes->isNullValue())
return EraseInstFromFunction(CI);
if (ConstantInt *CI = dyn_cast<ConstantInt>(NumBytes))
if (CI->getZExtValue() == 1) {
// Replace the instruction with just byte operations. We would
// transform other cases to loads/stores, but we don't know if
// alignment is sufficient.
}
}
// No other transformations apply to volatile transfers.
if (MI->isVolatile())
return nullptr;
// If we have a memmove and the source operation is a constant global,
// then the source and dest pointers can't alias, so we can change this
// into a call to memcpy.
if (MemMoveInst *MMI = dyn_cast<MemMoveInst>(MI)) {
if (GlobalVariable *GVSrc = dyn_cast<GlobalVariable>(MMI->getSource()))
if (GVSrc->isConstant()) {
Module *M = CI.getParent()->getParent()->getParent();
Intrinsic::ID MemCpyID = Intrinsic::memcpy;
Type *Tys[3] = { CI.getArgOperand(0)->getType(),
CI.getArgOperand(1)->getType(),
CI.getArgOperand(2)->getType() };
CI.setCalledFunction(Intrinsic::getDeclaration(M, MemCpyID, Tys));
Changed = true;
}
}
if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(MI)) {
// memmove(x,x,size) -> noop.
if (MTI->getSource() == MTI->getDest())
return EraseInstFromFunction(CI);
}
// If we can determine a pointer alignment that is bigger than currently
// set, update the alignment.
if (isa<MemTransferInst>(MI)) {
if (Instruction *I = SimplifyMemTransfer(MI))
return I;
} else if (MemSetInst *MSI = dyn_cast<MemSetInst>(MI)) {
if (Instruction *I = SimplifyMemSet(MSI))
return I;
}
if (Changed) return II;
}
switch (II->getIntrinsicID()) {
default: break;
case Intrinsic::objectsize: {
uint64_t Size;
if (getObjectSize(II->getArgOperand(0), Size, DL, TLI))
return ReplaceInstUsesWith(CI, ConstantInt::get(CI.getType(), Size));
return nullptr;
}
case Intrinsic::bswap: {
Value *IIOperand = II->getArgOperand(0);
Value *X = nullptr;
// bswap(bswap(x)) -> x
if (match(IIOperand, m_BSwap(m_Value(X))))
return ReplaceInstUsesWith(CI, X);
// bswap(trunc(bswap(x))) -> trunc(lshr(x, c))
if (match(IIOperand, m_Trunc(m_BSwap(m_Value(X))))) {
unsigned C = X->getType()->getPrimitiveSizeInBits() -
IIOperand->getType()->getPrimitiveSizeInBits();
Value *CV = ConstantInt::get(X->getType(), C);
Value *V = Builder->CreateLShr(X, CV);
return new TruncInst(V, IIOperand->getType());
}
break;
}
case Intrinsic::powi:
if (ConstantInt *Power = dyn_cast<ConstantInt>(II->getArgOperand(1))) {
// powi(x, 0) -> 1.0
if (Power->isZero())
return ReplaceInstUsesWith(CI, ConstantFP::get(CI.getType(), 1.0));
// powi(x, 1) -> x
if (Power->isOne())
return ReplaceInstUsesWith(CI, II->getArgOperand(0));
// powi(x, -1) -> 1/x
if (Power->isAllOnesValue())
return BinaryOperator::CreateFDiv(ConstantFP::get(CI.getType(), 1.0),
II->getArgOperand(0));
}
break;
case Intrinsic::cttz: {
// If all bits below the first known one are known zero,
// this value is constant.
IntegerType *IT = dyn_cast<IntegerType>(II->getArgOperand(0)->getType());
// FIXME: Try to simplify vectors of integers.
if (!IT) break;
uint32_t BitWidth = IT->getBitWidth();
APInt KnownZero(BitWidth, 0);
APInt KnownOne(BitWidth, 0);
computeKnownBits(II->getArgOperand(0), KnownZero, KnownOne, 0, II);
unsigned TrailingZeros = KnownOne.countTrailingZeros();
APInt Mask(APInt::getLowBitsSet(BitWidth, TrailingZeros));
if ((Mask & KnownZero) == Mask)
return ReplaceInstUsesWith(CI, ConstantInt::get(IT,
APInt(BitWidth, TrailingZeros)));
}
break;
case Intrinsic::ctlz: {
// If all bits above the first known one are known zero,
// this value is constant.
IntegerType *IT = dyn_cast<IntegerType>(II->getArgOperand(0)->getType());
// FIXME: Try to simplify vectors of integers.
if (!IT) break;
uint32_t BitWidth = IT->getBitWidth();
APInt KnownZero(BitWidth, 0);
APInt KnownOne(BitWidth, 0);
computeKnownBits(II->getArgOperand(0), KnownZero, KnownOne, 0, II);
unsigned LeadingZeros = KnownOne.countLeadingZeros();
APInt Mask(APInt::getHighBitsSet(BitWidth, LeadingZeros));
if ((Mask & KnownZero) == Mask)
return ReplaceInstUsesWith(CI, ConstantInt::get(IT,
APInt(BitWidth, LeadingZeros)));
}
break;
case Intrinsic::uadd_with_overflow:
case Intrinsic::sadd_with_overflow:
case Intrinsic::umul_with_overflow:
case Intrinsic::smul_with_overflow:
if (isa<Constant>(II->getArgOperand(0)) &&
!isa<Constant>(II->getArgOperand(1))) {
// Canonicalize constants into the RHS.
Value *LHS = II->getArgOperand(0);
II->setArgOperand(0, II->getArgOperand(1));
II->setArgOperand(1, LHS);
return II;
}
LLVM_FALLTHROUGH; // HLSL Change
case Intrinsic::usub_with_overflow:
case Intrinsic::ssub_with_overflow: {
OverflowCheckFlavor OCF =
IntrinsicIDToOverflowCheckFlavor(II->getIntrinsicID());
assert(OCF != OCF_INVALID && "unexpected!");
Value *OperationResult = nullptr;
Constant *OverflowResult = nullptr;
if (OptimizeOverflowCheck(OCF, II->getArgOperand(0), II->getArgOperand(1),
*II, OperationResult, OverflowResult))
return CreateOverflowTuple(II, OperationResult, OverflowResult);
break;
}
case Intrinsic::minnum:
case Intrinsic::maxnum: {
Value *Arg0 = II->getArgOperand(0);
Value *Arg1 = II->getArgOperand(1);
// fmin(x, x) -> x
if (Arg0 == Arg1)
return ReplaceInstUsesWith(CI, Arg0);
const ConstantFP *C0 = dyn_cast<ConstantFP>(Arg0);
const ConstantFP *C1 = dyn_cast<ConstantFP>(Arg1);
// Canonicalize constants into the RHS.
if (C0 && !C1) {
II->setArgOperand(0, Arg1);
II->setArgOperand(1, Arg0);
return II;
}
// fmin(x, nan) -> x
if (C1 && C1->isNaN())
return ReplaceInstUsesWith(CI, Arg0);
// This is the value because if undef were NaN, we would return the other
// value and cannot return a NaN unless both operands are.
//
// fmin(undef, x) -> x
if (isa<UndefValue>(Arg0))
return ReplaceInstUsesWith(CI, Arg1);
// fmin(x, undef) -> x
if (isa<UndefValue>(Arg1))
return ReplaceInstUsesWith(CI, Arg0);
Value *X = nullptr;
Value *Y = nullptr;
if (II->getIntrinsicID() == Intrinsic::minnum) {
// fmin(x, fmin(x, y)) -> fmin(x, y)
// fmin(y, fmin(x, y)) -> fmin(x, y)
if (match(Arg1, m_FMin(m_Value(X), m_Value(Y)))) {
if (Arg0 == X || Arg0 == Y)
return ReplaceInstUsesWith(CI, Arg1);
}
// fmin(fmin(x, y), x) -> fmin(x, y)
// fmin(fmin(x, y), y) -> fmin(x, y)
if (match(Arg0, m_FMin(m_Value(X), m_Value(Y)))) {
if (Arg1 == X || Arg1 == Y)
return ReplaceInstUsesWith(CI, Arg0);
}
// TODO: fmin(nnan x, inf) -> x
// TODO: fmin(nnan ninf x, flt_max) -> x
if (C1 && C1->isInfinity()) {
// fmin(x, -inf) -> -inf
if (C1->isNegative())
return ReplaceInstUsesWith(CI, Arg1);
}
} else {
assert(II->getIntrinsicID() == Intrinsic::maxnum);
// fmax(x, fmax(x, y)) -> fmax(x, y)
// fmax(y, fmax(x, y)) -> fmax(x, y)
if (match(Arg1, m_FMax(m_Value(X), m_Value(Y)))) {
if (Arg0 == X || Arg0 == Y)
return ReplaceInstUsesWith(CI, Arg1);
}
// fmax(fmax(x, y), x) -> fmax(x, y)
// fmax(fmax(x, y), y) -> fmax(x, y)
if (match(Arg0, m_FMax(m_Value(X), m_Value(Y)))) {
if (Arg1 == X || Arg1 == Y)
return ReplaceInstUsesWith(CI, Arg0);
}
// TODO: fmax(nnan x, -inf) -> x
// TODO: fmax(nnan ninf x, -flt_max) -> x
if (C1 && C1->isInfinity()) {
// fmax(x, inf) -> inf
if (!C1->isNegative())
return ReplaceInstUsesWith(CI, Arg1);
}
}
break;
}
#if 0 // HLSL Change - remove platform intrinsics
case Intrinsic::ppc_altivec_lvx:
case Intrinsic::ppc_altivec_lvxl:
// Turn PPC lvx -> load if the pointer is known aligned.
if (getOrEnforceKnownAlignment(II->getArgOperand(0), 16, DL, II, AC, DT) >=
16) {
Value *Ptr = Builder->CreateBitCast(II->getArgOperand(0),
PointerType::getUnqual(II->getType()));
return new LoadInst(Ptr);
}
break;
case Intrinsic::ppc_vsx_lxvw4x:
case Intrinsic::ppc_vsx_lxvd2x: {
// Turn PPC VSX loads into normal loads.
Value *Ptr = Builder->CreateBitCast(II->getArgOperand(0),
PointerType::getUnqual(II->getType()));
return new LoadInst(Ptr, Twine(""), false, 1);
}
case Intrinsic::ppc_altivec_stvx:
case Intrinsic::ppc_altivec_stvxl:
// Turn stvx -> store if the pointer is known aligned.
if (getOrEnforceKnownAlignment(II->getArgOperand(1), 16, DL, II, AC, DT) >=
16) {
Type *OpPtrTy =
PointerType::getUnqual(II->getArgOperand(0)->getType());
Value *Ptr = Builder->CreateBitCast(II->getArgOperand(1), OpPtrTy);
return new StoreInst(II->getArgOperand(0), Ptr);
}
break;
case Intrinsic::ppc_vsx_stxvw4x:
case Intrinsic::ppc_vsx_stxvd2x: {
// Turn PPC VSX stores into normal stores.
Type *OpPtrTy = PointerType::getUnqual(II->getArgOperand(0)->getType());
Value *Ptr = Builder->CreateBitCast(II->getArgOperand(1), OpPtrTy);
return new StoreInst(II->getArgOperand(0), Ptr, false, 1);
}
case Intrinsic::ppc_qpx_qvlfs:
// Turn PPC QPX qvlfs -> load if the pointer is known aligned.
if (getOrEnforceKnownAlignment(II->getArgOperand(0), 16, DL, II, AC, DT) >=
16) {
Type *VTy = VectorType::get(Builder->getFloatTy(),
II->getType()->getVectorNumElements());
Value *Ptr = Builder->CreateBitCast(II->getArgOperand(0),
PointerType::getUnqual(VTy));
Value *Load = Builder->CreateLoad(Ptr);
return new FPExtInst(Load, II->getType());
}
break;
case Intrinsic::ppc_qpx_qvlfd:
// Turn PPC QPX qvlfd -> load if the pointer is known aligned.
if (getOrEnforceKnownAlignment(II->getArgOperand(0), 32, DL, II, AC, DT) >=
32) {
Value *Ptr = Builder->CreateBitCast(II->getArgOperand(0),
PointerType::getUnqual(II->getType()));
return new LoadInst(Ptr);
}
break;
case Intrinsic::ppc_qpx_qvstfs:
// Turn PPC QPX qvstfs -> store if the pointer is known aligned.
if (getOrEnforceKnownAlignment(II->getArgOperand(1), 16, DL, II, AC, DT) >=
16) {
Type *VTy = VectorType::get(Builder->getFloatTy(),
II->getArgOperand(0)->getType()->getVectorNumElements());
Value *TOp = Builder->CreateFPTrunc(II->getArgOperand(0), VTy);
Type *OpPtrTy = PointerType::getUnqual(VTy);
Value *Ptr = Builder->CreateBitCast(II->getArgOperand(1), OpPtrTy);
return new StoreInst(TOp, Ptr);
}
break;
case Intrinsic::ppc_qpx_qvstfd:
// Turn PPC QPX qvstfd -> store if the pointer is known aligned.
if (getOrEnforceKnownAlignment(II->getArgOperand(1), 32, DL, II, AC, DT) >=
32) {
Type *OpPtrTy =
PointerType::getUnqual(II->getArgOperand(0)->getType());
Value *Ptr = Builder->CreateBitCast(II->getArgOperand(1), OpPtrTy);
return new StoreInst(II->getArgOperand(0), Ptr);
}
break;
case Intrinsic::x86_sse_storeu_ps:
case Intrinsic::x86_sse2_storeu_pd:
case Intrinsic::x86_sse2_storeu_dq:
// Turn X86 storeu -> store if the pointer is known aligned.
if (getOrEnforceKnownAlignment(II->getArgOperand(0), 16, DL, II, AC, DT) >=
16) {
Type *OpPtrTy =
PointerType::getUnqual(II->getArgOperand(1)->getType());
Value *Ptr = Builder->CreateBitCast(II->getArgOperand(0), OpPtrTy);
return new StoreInst(II->getArgOperand(1), Ptr);
}
break;
case Intrinsic::x86_sse_cvtss2si:
case Intrinsic::x86_sse_cvtss2si64:
case Intrinsic::x86_sse_cvttss2si:
case Intrinsic::x86_sse_cvttss2si64:
case Intrinsic::x86_sse2_cvtsd2si:
case Intrinsic::x86_sse2_cvtsd2si64:
case Intrinsic::x86_sse2_cvttsd2si:
case Intrinsic::x86_sse2_cvttsd2si64: {
// These intrinsics only demand the 0th element of their input vectors. If
// we can simplify the input based on that, do so now.
unsigned VWidth =
cast<VectorType>(II->getArgOperand(0)->getType())->getNumElements();
APInt DemandedElts(VWidth, 1);
APInt UndefElts(VWidth, 0);
if (Value *V = SimplifyDemandedVectorElts(II->getArgOperand(0),
DemandedElts, UndefElts)) {
II->setArgOperand(0, V);
return II;
}
break;
}
// Constant fold <A x Bi> << Ci.
// FIXME: We don't handle _dq because it's a shift of an i128, but is
// represented in the IR as <2 x i64>. A per element shift is wrong.
case Intrinsic::x86_sse2_psll_d:
case Intrinsic::x86_sse2_psll_q:
case Intrinsic::x86_sse2_psll_w:
case Intrinsic::x86_sse2_pslli_d:
case Intrinsic::x86_sse2_pslli_q:
case Intrinsic::x86_sse2_pslli_w:
case Intrinsic::x86_avx2_psll_d:
case Intrinsic::x86_avx2_psll_q:
case Intrinsic::x86_avx2_psll_w:
case Intrinsic::x86_avx2_pslli_d:
case Intrinsic::x86_avx2_pslli_q:
case Intrinsic::x86_avx2_pslli_w:
case Intrinsic::x86_sse2_psrl_d:
case Intrinsic::x86_sse2_psrl_q:
case Intrinsic::x86_sse2_psrl_w:
case Intrinsic::x86_sse2_psrli_d:
case Intrinsic::x86_sse2_psrli_q:
case Intrinsic::x86_sse2_psrli_w:
case Intrinsic::x86_avx2_psrl_d:
case Intrinsic::x86_avx2_psrl_q:
case Intrinsic::x86_avx2_psrl_w:
case Intrinsic::x86_avx2_psrli_d:
case Intrinsic::x86_avx2_psrli_q:
case Intrinsic::x86_avx2_psrli_w: {
// Simplify if count is constant. To 0 if >= BitWidth,
// otherwise to shl/lshr.
auto CDV = dyn_cast<ConstantDataVector>(II->getArgOperand(1));
auto CInt = dyn_cast<ConstantInt>(II->getArgOperand(1));
if (!CDV && !CInt)
break;
ConstantInt *Count;
if (CDV)
Count = cast<ConstantInt>(CDV->getElementAsConstant(0));
else
Count = CInt;
auto Vec = II->getArgOperand(0);
auto VT = cast<VectorType>(Vec->getType());
if (Count->getZExtValue() >
VT->getElementType()->getPrimitiveSizeInBits() - 1)
return ReplaceInstUsesWith(
CI, ConstantAggregateZero::get(Vec->getType()));
bool isPackedShiftLeft = true;
switch (II->getIntrinsicID()) {
default : break;
case Intrinsic::x86_sse2_psrl_d:
case Intrinsic::x86_sse2_psrl_q:
case Intrinsic::x86_sse2_psrl_w:
case Intrinsic::x86_sse2_psrli_d:
case Intrinsic::x86_sse2_psrli_q:
case Intrinsic::x86_sse2_psrli_w:
case Intrinsic::x86_avx2_psrl_d:
case Intrinsic::x86_avx2_psrl_q:
case Intrinsic::x86_avx2_psrl_w:
case Intrinsic::x86_avx2_psrli_d:
case Intrinsic::x86_avx2_psrli_q:
case Intrinsic::x86_avx2_psrli_w: isPackedShiftLeft = false; break;
}
unsigned VWidth = VT->getNumElements();
// Get a constant vector of the same type as the first operand.
auto VTCI = ConstantInt::get(VT->getElementType(), Count->getZExtValue());
if (isPackedShiftLeft)
return BinaryOperator::CreateShl(Vec,
Builder->CreateVectorSplat(VWidth, VTCI));
return BinaryOperator::CreateLShr(Vec,
Builder->CreateVectorSplat(VWidth, VTCI));
}
case Intrinsic::x86_sse41_pmovsxbw:
case Intrinsic::x86_sse41_pmovsxwd:
case Intrinsic::x86_sse41_pmovsxdq:
case Intrinsic::x86_sse41_pmovzxbw:
case Intrinsic::x86_sse41_pmovzxwd:
case Intrinsic::x86_sse41_pmovzxdq: {
// pmov{s|z}x ignores the upper half of their input vectors.
unsigned VWidth =
cast<VectorType>(II->getArgOperand(0)->getType())->getNumElements();
unsigned LowHalfElts = VWidth / 2;
APInt InputDemandedElts(APInt::getBitsSet(VWidth, 0, LowHalfElts));
APInt UndefElts(VWidth, 0);
if (Value *TmpV = SimplifyDemandedVectorElts(
II->getArgOperand(0), InputDemandedElts, UndefElts)) {
II->setArgOperand(0, TmpV);
return II;
}
break;
}
case Intrinsic::x86_sse41_insertps:
if (Value *V = SimplifyX86insertps(*II, *Builder))
return ReplaceInstUsesWith(*II, V);
break;
case Intrinsic::x86_sse4a_insertqi: {
// insertqi x, y, 64, 0 can just copy y's lower bits and leave the top
// ones undef
// TODO: eventually we should lower this intrinsic to IR
if (auto CIWidth = dyn_cast<ConstantInt>(II->getArgOperand(2))) {
if (auto CIStart = dyn_cast<ConstantInt>(II->getArgOperand(3))) {
unsigned Index = CIStart->getZExtValue();
// From AMD documentation: "a value of zero in the field length is
// defined as length of 64".
unsigned Length = CIWidth->equalsInt(0) ? 64 : CIWidth->getZExtValue();
// From AMD documentation: "If the sum of the bit index + length field
// is greater than 64, the results are undefined".
// Note that both field index and field length are 8-bit quantities.
// Since variables 'Index' and 'Length' are unsigned values
// obtained from zero-extending field index and field length
// respectively, their sum should never wrap around.
if ((Index + Length) > 64)
return ReplaceInstUsesWith(CI, UndefValue::get(II->getType()));
if (Length == 64 && Index == 0) {
Value *Vec = II->getArgOperand(1);
Value *Undef = UndefValue::get(Vec->getType());
const uint32_t Mask[] = { 0, 2 };
return ReplaceInstUsesWith(
CI,
Builder->CreateShuffleVector(
Vec, Undef, ConstantDataVector::get(
II->getContext(), makeArrayRef(Mask))));
} else if (auto Source =
dyn_cast<IntrinsicInst>(II->getArgOperand(0))) {
if (Source->hasOneUse() &&
Source->getArgOperand(1) == II->getArgOperand(1)) {
// If the source of the insert has only one use and it's another
// insert (and they're both inserting from the same vector), try to
// bundle both together.
auto CISourceWidth =
dyn_cast<ConstantInt>(Source->getArgOperand(2));
auto CISourceStart =
dyn_cast<ConstantInt>(Source->getArgOperand(3));
if (CISourceStart && CISourceWidth) {
unsigned Start = CIStart->getZExtValue();
unsigned Width = CIWidth->getZExtValue();
unsigned End = Start + Width;
unsigned SourceStart = CISourceStart->getZExtValue();
unsigned SourceWidth = CISourceWidth->getZExtValue();
unsigned SourceEnd = SourceStart + SourceWidth;
unsigned NewStart, NewWidth;
bool ShouldReplace = false;
if (Start <= SourceStart && SourceStart <= End) {
NewStart = Start;
NewWidth = std::max(End, SourceEnd) - NewStart;
ShouldReplace = true;
} else if (SourceStart <= Start && Start <= SourceEnd) {
NewStart = SourceStart;
NewWidth = std::max(SourceEnd, End) - NewStart;
ShouldReplace = true;
}
if (ShouldReplace) {
Constant *ConstantWidth = ConstantInt::get(
II->getArgOperand(2)->getType(), NewWidth, false);
Constant *ConstantStart = ConstantInt::get(
II->getArgOperand(3)->getType(), NewStart, false);
Value *Args[4] = { Source->getArgOperand(0),
II->getArgOperand(1), ConstantWidth,
ConstantStart };
Module *M = CI.getParent()->getParent()->getParent();
Value *F =
Intrinsic::getDeclaration(M, Intrinsic::x86_sse4a_insertqi);
return ReplaceInstUsesWith(CI, Builder->CreateCall(F, Args));
}
}
}
}
}
}
break;
}
case Intrinsic::x86_sse41_pblendvb:
case Intrinsic::x86_sse41_blendvps:
case Intrinsic::x86_sse41_blendvpd:
case Intrinsic::x86_avx_blendv_ps_256:
case Intrinsic::x86_avx_blendv_pd_256:
case Intrinsic::x86_avx2_pblendvb: {
// Convert blendv* to vector selects if the mask is constant.
// This optimization is convoluted because the intrinsic is defined as
// getting a vector of floats or doubles for the ps and pd versions.
// FIXME: That should be changed.
Value *Mask = II->getArgOperand(2);
if (auto C = dyn_cast<ConstantDataVector>(Mask)) {
auto Tyi1 = Builder->getInt1Ty();
auto SelectorType = cast<VectorType>(Mask->getType());
auto EltTy = SelectorType->getElementType();
unsigned Size = SelectorType->getNumElements();
unsigned BitWidth =
EltTy->isFloatTy()
? 32
: (EltTy->isDoubleTy() ? 64 : EltTy->getIntegerBitWidth());
assert((BitWidth == 64 || BitWidth == 32 || BitWidth == 8) &&
"Wrong arguments for variable blend intrinsic");
SmallVector<Constant *, 32> Selectors;
for (unsigned I = 0; I < Size; ++I) {
// The intrinsics only read the top bit
uint64_t Selector;
if (BitWidth == 8)
Selector = C->getElementAsInteger(I);
else
Selector = C->getElementAsAPFloat(I).bitcastToAPInt().getZExtValue();
Selectors.push_back(ConstantInt::get(Tyi1, Selector >> (BitWidth - 1)));
}
auto NewSelector = ConstantVector::get(Selectors);
return SelectInst::Create(NewSelector, II->getArgOperand(1),
II->getArgOperand(0), "blendv");
} else {
break;
}
}
case Intrinsic::x86_avx_vpermilvar_ps:
case Intrinsic::x86_avx_vpermilvar_ps_256:
case Intrinsic::x86_avx_vpermilvar_pd:
case Intrinsic::x86_avx_vpermilvar_pd_256: {
// Convert vpermil* to shufflevector if the mask is constant.
Value *V = II->getArgOperand(1);
unsigned Size = cast<VectorType>(V->getType())->getNumElements();
assert(Size == 8 || Size == 4 || Size == 2);
uint32_t Indexes[8];
if (auto C = dyn_cast<ConstantDataVector>(V)) {
// The intrinsics only read one or two bits, clear the rest.
for (unsigned I = 0; I < Size; ++I) {
uint32_t Index = C->getElementAsInteger(I) & 0x3;
if (II->getIntrinsicID() == Intrinsic::x86_avx_vpermilvar_pd ||
II->getIntrinsicID() == Intrinsic::x86_avx_vpermilvar_pd_256)
Index >>= 1;
Indexes[I] = Index;
}
} else if (isa<ConstantAggregateZero>(V)) {
for (unsigned I = 0; I < Size; ++I)
Indexes[I] = 0;
} else {
break;
}
// The _256 variants are a bit trickier since the mask bits always index
// into the corresponding 128 half. In order to convert to a generic
// shuffle, we have to make that explicit.
if (II->getIntrinsicID() == Intrinsic::x86_avx_vpermilvar_ps_256 ||
II->getIntrinsicID() == Intrinsic::x86_avx_vpermilvar_pd_256) {
for (unsigned I = Size / 2; I < Size; ++I)
Indexes[I] += Size / 2;
}
auto NewC =
ConstantDataVector::get(V->getContext(), makeArrayRef(Indexes, Size));
auto V1 = II->getArgOperand(0);
auto V2 = UndefValue::get(V1->getType());
auto Shuffle = Builder->CreateShuffleVector(V1, V2, NewC);
return ReplaceInstUsesWith(CI, Shuffle);
}
case Intrinsic::x86_avx_vperm2f128_pd_256:
case Intrinsic::x86_avx_vperm2f128_ps_256:
case Intrinsic::x86_avx_vperm2f128_si_256:
case Intrinsic::x86_avx2_vperm2i128:
if (Value *V = SimplifyX86vperm2(*II, *Builder))
return ReplaceInstUsesWith(*II, V);
break;
case Intrinsic::ppc_altivec_vperm:
// Turn vperm(V1,V2,mask) -> shuffle(V1,V2,mask) if mask is a constant.
// Note that ppc_altivec_vperm has a big-endian bias, so when creating
// a vectorshuffle for little endian, we must undo the transformation
// performed on vec_perm in altivec.h. That is, we must complement
// the permutation mask with respect to 31 and reverse the order of
// V1 and V2.
if (Constant *Mask = dyn_cast<Constant>(II->getArgOperand(2))) {
assert(Mask->getType()->getVectorNumElements() == 16 &&
"Bad type for intrinsic!");
// Check that all of the elements are integer constants or undefs.
bool AllEltsOk = true;
for (unsigned i = 0; i != 16; ++i) {
Constant *Elt = Mask->getAggregateElement(i);
if (!Elt || !(isa<ConstantInt>(Elt) || isa<UndefValue>(Elt))) {
AllEltsOk = false;
break;
}
}
if (AllEltsOk) {
// Cast the input vectors to byte vectors.
Value *Op0 = Builder->CreateBitCast(II->getArgOperand(0),
Mask->getType());
Value *Op1 = Builder->CreateBitCast(II->getArgOperand(1),
Mask->getType());
Value *Result = UndefValue::get(Op0->getType());
// Only extract each element once.
Value *ExtractedElts[32];
memset(ExtractedElts, 0, sizeof(ExtractedElts));
for (unsigned i = 0; i != 16; ++i) {
if (isa<UndefValue>(Mask->getAggregateElement(i)))
continue;
unsigned Idx =
cast<ConstantInt>(Mask->getAggregateElement(i))->getZExtValue();
Idx &= 31; // Match the hardware behavior.
if (DL.isLittleEndian())
Idx = 31 - Idx;
if (!ExtractedElts[Idx]) {
Value *Op0ToUse = (DL.isLittleEndian()) ? Op1 : Op0;
Value *Op1ToUse = (DL.isLittleEndian()) ? Op0 : Op1;
ExtractedElts[Idx] =
Builder->CreateExtractElement(Idx < 16 ? Op0ToUse : Op1ToUse,
Builder->getInt32(Idx&15));
}
// Insert this value into the result vector.
Result = Builder->CreateInsertElement(Result, ExtractedElts[Idx],
Builder->getInt32(i));
}
return CastInst::Create(Instruction::BitCast, Result, CI.getType());
}
}
break;
case Intrinsic::arm_neon_vld1:
case Intrinsic::arm_neon_vld2:
case Intrinsic::arm_neon_vld3:
case Intrinsic::arm_neon_vld4:
case Intrinsic::arm_neon_vld2lane:
case Intrinsic::arm_neon_vld3lane:
case Intrinsic::arm_neon_vld4lane:
case Intrinsic::arm_neon_vst1:
case Intrinsic::arm_neon_vst2:
case Intrinsic::arm_neon_vst3:
case Intrinsic::arm_neon_vst4:
case Intrinsic::arm_neon_vst2lane:
case Intrinsic::arm_neon_vst3lane:
case Intrinsic::arm_neon_vst4lane: {
unsigned MemAlign = getKnownAlignment(II->getArgOperand(0), DL, II, AC, DT);
unsigned AlignArg = II->getNumArgOperands() - 1;
ConstantInt *IntrAlign = dyn_cast<ConstantInt>(II->getArgOperand(AlignArg));
if (IntrAlign && IntrAlign->getZExtValue() < MemAlign) {
II->setArgOperand(AlignArg,
ConstantInt::get(Type::getInt32Ty(II->getContext()),
MemAlign, false));
return II;
}
break;
}
case Intrinsic::arm_neon_vmulls:
case Intrinsic::arm_neon_vmullu:
case Intrinsic::aarch64_neon_smull:
case Intrinsic::aarch64_neon_umull: {
Value *Arg0 = II->getArgOperand(0);
Value *Arg1 = II->getArgOperand(1);
// Handle mul by zero first:
if (isa<ConstantAggregateZero>(Arg0) || isa<ConstantAggregateZero>(Arg1)) {
return ReplaceInstUsesWith(CI, ConstantAggregateZero::get(II->getType()));
}
// Check for constant LHS & RHS - in this case we just simplify.
bool Zext = (II->getIntrinsicID() == Intrinsic::arm_neon_vmullu ||
II->getIntrinsicID() == Intrinsic::aarch64_neon_umull);
VectorType *NewVT = cast<VectorType>(II->getType());
if (Constant *CV0 = dyn_cast<Constant>(Arg0)) {
if (Constant *CV1 = dyn_cast<Constant>(Arg1)) {
CV0 = ConstantExpr::getIntegerCast(CV0, NewVT, /*isSigned=*/!Zext);
CV1 = ConstantExpr::getIntegerCast(CV1, NewVT, /*isSigned=*/!Zext);
return ReplaceInstUsesWith(CI, ConstantExpr::getMul(CV0, CV1));
}
// Couldn't simplify - canonicalize constant to the RHS.
std::swap(Arg0, Arg1);
}
// Handle mul by one:
if (Constant *CV1 = dyn_cast<Constant>(Arg1))
if (ConstantInt *Splat =
dyn_cast_or_null<ConstantInt>(CV1->getSplatValue()))
if (Splat->isOne())
return CastInst::CreateIntegerCast(Arg0, II->getType(),
/*isSigned=*/!Zext);
break;
}
case Intrinsic::AMDGPU_rcp: {
if (const ConstantFP *C = dyn_cast<ConstantFP>(II->getArgOperand(0))) {
const APFloat &ArgVal = C->getValueAPF();
APFloat Val(ArgVal.getSemantics(), 1.0);
APFloat::opStatus Status = Val.divide(ArgVal,
APFloat::rmNearestTiesToEven);
// Only do this if it was exact and therefore not dependent on the
// rounding mode.
if (Status == APFloat::opOK)
return ReplaceInstUsesWith(CI, ConstantFP::get(II->getContext(), Val));
}
break;
}
#endif // HLSL Change - remove platform intrinsics
case Intrinsic::stackrestore: {
// If the save is right next to the restore, remove the restore. This can
// happen when variable allocas are DCE'd.
if (IntrinsicInst *SS = dyn_cast<IntrinsicInst>(II->getArgOperand(0))) {
if (SS->getIntrinsicID() == Intrinsic::stacksave) {
BasicBlock::iterator BI = SS;
if (&*++BI == II)
return EraseInstFromFunction(CI);
}
}
// Scan down this block to see if there is another stack restore in the
// same block without an intervening call/alloca.
BasicBlock::iterator BI = II;
TerminatorInst *TI = II->getParent()->getTerminator();
bool CannotRemove = false;
for (++BI; &*BI != TI; ++BI) {
if (isa<AllocaInst>(BI)) {
CannotRemove = true;
break;
}
if (CallInst *BCI = dyn_cast<CallInst>(BI)) {
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(BCI)) {
// If there is a stackrestore below this one, remove this one.
if (II->getIntrinsicID() == Intrinsic::stackrestore)
return EraseInstFromFunction(CI);
// Otherwise, ignore the intrinsic.
} else {
// If we found a non-intrinsic call, we can't remove the stack
// restore.
CannotRemove = true;
break;
}
}
}
// If the stack restore is in a return, resume, or unwind block and if there
// are no allocas or calls between the restore and the return, nuke the
// restore.
if (!CannotRemove && (isa<ReturnInst>(TI) || isa<ResumeInst>(TI)))
return EraseInstFromFunction(CI);
break;
}
case Intrinsic::assume: {
// Canonicalize assume(a && b) -> assume(a); assume(b);
// Note: New assumption intrinsics created here are registered by
// the InstCombineIRInserter object.
Value *IIOperand = II->getArgOperand(0), *A, *B,
*AssumeIntrinsic = II->getCalledValue();
if (match(IIOperand, m_And(m_Value(A), m_Value(B)))) {
Builder->CreateCall(AssumeIntrinsic, A, II->getName());
Builder->CreateCall(AssumeIntrinsic, B, II->getName());
return EraseInstFromFunction(*II);
}
// assume(!(a || b)) -> assume(!a); assume(!b);
if (match(IIOperand, m_Not(m_Or(m_Value(A), m_Value(B))))) {
Builder->CreateCall(AssumeIntrinsic, Builder->CreateNot(A),
II->getName());
Builder->CreateCall(AssumeIntrinsic, Builder->CreateNot(B),
II->getName());
return EraseInstFromFunction(*II);
}
// assume( (load addr) != null ) -> add 'nonnull' metadata to load
// (if assume is valid at the load)
if (ICmpInst* ICmp = dyn_cast<ICmpInst>(IIOperand)) {
Value *LHS = ICmp->getOperand(0);
Value *RHS = ICmp->getOperand(1);
if (ICmpInst::ICMP_NE == ICmp->getPredicate() &&
isa<LoadInst>(LHS) &&
isa<Constant>(RHS) &&
RHS->getType()->isPointerTy() &&
cast<Constant>(RHS)->isNullValue()) {
LoadInst* LI = cast<LoadInst>(LHS);
if (isValidAssumeForContext(II, LI, DT)) {
MDNode *MD = MDNode::get(II->getContext(), None);
LI->setMetadata(LLVMContext::MD_nonnull, MD);
return EraseInstFromFunction(*II);
}
}
// TODO: apply nonnull return attributes to calls and invokes
// TODO: apply range metadata for range check patterns?
}
// If there is a dominating assume with the same condition as this one,
// then this one is redundant, and should be removed.
APInt KnownZero(1, 0), KnownOne(1, 0);
computeKnownBits(IIOperand, KnownZero, KnownOne, 0, II);
if (KnownOne.isAllOnesValue())
return EraseInstFromFunction(*II);
break;
}
case Intrinsic::experimental_gc_relocate: {
// Translate facts known about a pointer before relocating into
// facts about the relocate value, while being careful to
// preserve relocation semantics.
GCRelocateOperands Operands(II);
Value *DerivedPtr = Operands.getDerivedPtr();
auto *GCRelocateType = cast<PointerType>(II->getType());
// Remove the relocation if unused, note that this check is required
// to prevent the cases below from looping forever.
if (II->use_empty())
return EraseInstFromFunction(*II);
// Undef is undef, even after relocation.
// TODO: provide a hook for this in GCStrategy. This is clearly legal for
// most practical collectors, but there was discussion in the review thread
// about whether it was legal for all possible collectors.
if (isa<UndefValue>(DerivedPtr)) {
// gc_relocate is uncasted. Use undef of gc_relocate's type to replace it.
return ReplaceInstUsesWith(*II, UndefValue::get(GCRelocateType));
}
// The relocation of null will be null for most any collector.
// TODO: provide a hook for this in GCStrategy. There might be some weird
// collector this property does not hold for.
if (isa<ConstantPointerNull>(DerivedPtr)) {
// gc_relocate is uncasted. Use null-pointer of gc_relocate's type to replace it.
return ReplaceInstUsesWith(*II, ConstantPointerNull::get(GCRelocateType));
}
// isKnownNonNull -> nonnull attribute
if (isKnownNonNull(DerivedPtr))
II->addAttribute(AttributeSet::ReturnIndex, Attribute::NonNull);
// isDereferenceablePointer -> deref attribute
if (isDereferenceablePointer(DerivedPtr, DL)) {
if (Argument *A = dyn_cast<Argument>(DerivedPtr)) {
uint64_t Bytes = A->getDereferenceableBytes();
II->addDereferenceableAttr(AttributeSet::ReturnIndex, Bytes);
}
}
// TODO: bitcast(relocate(p)) -> relocate(bitcast(p))
// Canonicalize on the type from the uses to the defs
// TODO: relocate((gep p, C, C2, ...)) -> gep(relocate(p), C, C2, ...)
}
}
return visitCallSite(II);
}
// InvokeInst simplification
//
Instruction *InstCombiner::visitInvokeInst(InvokeInst &II) {
return visitCallSite(&II);
}
/// isSafeToEliminateVarargsCast - If this cast does not affect the value
/// passed through the varargs area, we can eliminate the use of the cast.
static bool isSafeToEliminateVarargsCast(const CallSite CS,
const DataLayout &DL,
const CastInst *const CI,
const int ix) {
if (!CI->isLosslessCast())
return false;
// If this is a GC intrinsic, avoid munging types. We need types for
// statepoint reconstruction in SelectionDAG.
// TODO: This is probably something which should be expanded to all
// intrinsics since the entire point of intrinsics is that
// they are understandable by the optimizer.
if (isStatepoint(CS) || isGCRelocate(CS) || isGCResult(CS))
return false;
// The size of ByVal or InAlloca arguments is derived from the type, so we
// can't change to a type with a different size. If the size were
// passed explicitly we could avoid this check.
if (!CS.isByValOrInAllocaArgument(ix))
return true;
Type* SrcTy =
cast<PointerType>(CI->getOperand(0)->getType())->getElementType();
Type* DstTy = cast<PointerType>(CI->getType())->getElementType();
if (!SrcTy->isSized() || !DstTy->isSized())
return false;
if (DL.getTypeAllocSize(SrcTy) != DL.getTypeAllocSize(DstTy))
return false;
return true;
}
// Try to fold some different type of calls here.
// Currently we're only working with the checking functions, memcpy_chk,
// mempcpy_chk, memmove_chk, memset_chk, strcpy_chk, stpcpy_chk, strncpy_chk,
// strcat_chk and strncat_chk.
Instruction *InstCombiner::tryOptimizeCall(CallInst *CI) {
if (!CI->getCalledFunction()) return nullptr;
auto InstCombineRAUW = [this](Instruction *From, Value *With) {
ReplaceInstUsesWith(*From, With);
};
LibCallSimplifier Simplifier(DL, TLI, InstCombineRAUW);
if (Value *With = Simplifier.optimizeCall(CI)) {
++NumSimplified;
return CI->use_empty() ? CI : ReplaceInstUsesWith(*CI, With);
}
return nullptr;
}
static IntrinsicInst *FindInitTrampolineFromAlloca(Value *TrampMem) {
// Strip off at most one level of pointer casts, looking for an alloca. This
// is good enough in practice and simpler than handling any number of casts.
Value *Underlying = TrampMem->stripPointerCasts();
if (Underlying != TrampMem &&
(!Underlying->hasOneUse() || Underlying->user_back() != TrampMem))
return nullptr;
if (!isa<AllocaInst>(Underlying))
return nullptr;
IntrinsicInst *InitTrampoline = nullptr;
for (User *U : TrampMem->users()) {
IntrinsicInst *II = dyn_cast<IntrinsicInst>(U);
if (!II)
return nullptr;
if (II->getIntrinsicID() == Intrinsic::init_trampoline) {
if (InitTrampoline)
// More than one init_trampoline writes to this value. Give up.
return nullptr;
InitTrampoline = II;
continue;
}
if (II->getIntrinsicID() == Intrinsic::adjust_trampoline)
// Allow any number of calls to adjust.trampoline.
continue;
return nullptr;
}
// No call to init.trampoline found.
if (!InitTrampoline)
return nullptr;
// Check that the alloca is being used in the expected way.
if (InitTrampoline->getOperand(0) != TrampMem)
return nullptr;
return InitTrampoline;
}
static IntrinsicInst *FindInitTrampolineFromBB(IntrinsicInst *AdjustTramp,
Value *TrampMem) {
// Visit all the previous instructions in the basic block, and try to find a
// init.trampoline which has a direct path to the adjust.trampoline.
for (BasicBlock::iterator I = AdjustTramp,
E = AdjustTramp->getParent()->begin(); I != E; ) {
Instruction *Inst = --I;
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I))
if (II->getIntrinsicID() == Intrinsic::init_trampoline &&
II->getOperand(0) == TrampMem)
return II;
if (Inst->mayWriteToMemory())
return nullptr;
}
return nullptr;
}
// Given a call to llvm.adjust.trampoline, find and return the corresponding
// call to llvm.init.trampoline if the call to the trampoline can be optimized
// to a direct call to a function. Otherwise return NULL.
//
static IntrinsicInst *FindInitTrampoline(Value *Callee) {
Callee = Callee->stripPointerCasts();
IntrinsicInst *AdjustTramp = dyn_cast<IntrinsicInst>(Callee);
if (!AdjustTramp ||
AdjustTramp->getIntrinsicID() != Intrinsic::adjust_trampoline)
return nullptr;
Value *TrampMem = AdjustTramp->getOperand(0);
if (IntrinsicInst *IT = FindInitTrampolineFromAlloca(TrampMem))
return IT;
if (IntrinsicInst *IT = FindInitTrampolineFromBB(AdjustTramp, TrampMem))
return IT;
return nullptr;
}
// visitCallSite - Improvements for call and invoke instructions.
//
Instruction *InstCombiner::visitCallSite(CallSite CS) {
if (isAllocLikeFn(CS.getInstruction(), TLI))
return visitAllocSite(*CS.getInstruction());
bool Changed = false;
// Mark any parameters that are known to be non-null with the nonnull
// attribute. This is helpful for inlining calls to functions with null
// checks on their arguments.
unsigned ArgNo = 0;
for (Value *V : CS.args()) {
if (!CS.paramHasAttr(ArgNo+1, Attribute::NonNull) &&
isKnownNonNull(V)) {
AttributeSet AS = CS.getAttributes();
AS = AS.addAttribute(CS.getInstruction()->getContext(), ArgNo+1,
Attribute::NonNull);
CS.setAttributes(AS);
Changed = true;
}
ArgNo++;
}
assert(ArgNo == CS.arg_size() && "sanity check");
// If the callee is a pointer to a function, attempt to move any casts to the
// arguments of the call/invoke.
Value *Callee = CS.getCalledValue();
if (!isa<Function>(Callee) && transformConstExprCastCall(CS))
return nullptr;
if (Function *CalleeF = dyn_cast<Function>(Callee))
// If the call and callee calling conventions don't match, this call must
// be unreachable, as the call is undefined.
if (CalleeF->getCallingConv() != CS.getCallingConv() &&
// Only do this for calls to a function with a body. A prototype may
// not actually end up matching the implementation's calling conv for a
// variety of reasons (e.g. it may be written in assembly).
!CalleeF->isDeclaration()) {
Instruction *OldCall = CS.getInstruction();
new StoreInst(ConstantInt::getTrue(Callee->getContext()),
UndefValue::get(Type::getInt1PtrTy(Callee->getContext())),
OldCall);
// If OldCall does not return void then replaceAllUsesWith undef.
// This allows ValueHandlers and custom metadata to adjust itself.
if (!OldCall->getType()->isVoidTy())
ReplaceInstUsesWith(*OldCall, UndefValue::get(OldCall->getType()));
if (isa<CallInst>(OldCall))
return EraseInstFromFunction(*OldCall);
// We cannot remove an invoke, because it would change the CFG, just
// change the callee to a null pointer.
cast<InvokeInst>(OldCall)->setCalledFunction(
Constant::getNullValue(CalleeF->getType()));
return nullptr;
}
if (isa<ConstantPointerNull>(Callee) || isa<UndefValue>(Callee)) {
// If CS does not return void then replaceAllUsesWith undef.
// This allows ValueHandlers and custom metadata to adjust itself.
if (!CS.getInstruction()->getType()->isVoidTy())
ReplaceInstUsesWith(*CS.getInstruction(),
UndefValue::get(CS.getInstruction()->getType()));
if (isa<InvokeInst>(CS.getInstruction())) {
// Can't remove an invoke because we cannot change the CFG.
return nullptr;
}
// This instruction is not reachable, just remove it. We insert a store to
// undef so that we know that this code is not reachable, despite the fact
// that we can't modify the CFG here.
new StoreInst(ConstantInt::getTrue(Callee->getContext()),
UndefValue::get(Type::getInt1PtrTy(Callee->getContext())),
CS.getInstruction());
return EraseInstFromFunction(*CS.getInstruction());
}
if (IntrinsicInst *II = FindInitTrampoline(Callee))
return transformCallThroughTrampoline(CS, II);
PointerType *PTy = cast<PointerType>(Callee->getType());
FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
if (FTy->isVarArg()) {
int ix = FTy->getNumParams();
// See if we can optimize any arguments passed through the varargs area of
// the call.
for (CallSite::arg_iterator I = CS.arg_begin() + FTy->getNumParams(),
E = CS.arg_end(); I != E; ++I, ++ix) {
CastInst *CI = dyn_cast<CastInst>(*I);
if (CI && isSafeToEliminateVarargsCast(CS, DL, CI, ix)) {
*I = CI->getOperand(0);
Changed = true;
}
}
}
if (isa<InlineAsm>(Callee) && !CS.doesNotThrow()) {
// Inline asm calls cannot throw - mark them 'nounwind'.
CS.setDoesNotThrow();
Changed = true;
}
// Try to optimize the call if possible, we require DataLayout for most of
// this. None of these calls are seen as possibly dead so go ahead and
// delete the instruction now.
if (CallInst *CI = dyn_cast<CallInst>(CS.getInstruction())) {
Instruction *I = tryOptimizeCall(CI);
// If we changed something return the result, etc. Otherwise let
// the fallthrough check.
if (I) return EraseInstFromFunction(*I);
}
return Changed ? CS.getInstruction() : nullptr;
}
// transformConstExprCastCall - If the callee is a constexpr cast of a function,
// attempt to move the cast to the arguments of the call/invoke.
//
bool InstCombiner::transformConstExprCastCall(CallSite CS) {
Function *Callee =
dyn_cast<Function>(CS.getCalledValue()->stripPointerCasts());
if (!Callee)
return false;
// The prototype of thunks are a lie, don't try to directly call such
// functions.
if (Callee->hasFnAttribute("thunk"))
return false;
Instruction *Caller = CS.getInstruction();
const AttributeSet &CallerPAL = CS.getAttributes();
// Okay, this is a cast from a function to a different type. Unless doing so
// would cause a type conversion of one of our arguments, change this call to
// be a direct call with arguments casted to the appropriate types.
//
FunctionType *FT = Callee->getFunctionType();
Type *OldRetTy = Caller->getType();
Type *NewRetTy = FT->getReturnType();
// Check to see if we are changing the return type...
if (OldRetTy != NewRetTy) {
if (NewRetTy->isStructTy())
return false; // TODO: Handle multiple return values.
if (!CastInst::isBitOrNoopPointerCastable(NewRetTy, OldRetTy, DL)) {
if (Callee->isDeclaration())
return false; // Cannot transform this return value.
if (!Caller->use_empty() &&
// void -> non-void is handled specially
!NewRetTy->isVoidTy())
return false; // Cannot transform this return value.
}
if (!CallerPAL.isEmpty() && !Caller->use_empty()) {
AttrBuilder RAttrs(CallerPAL, AttributeSet::ReturnIndex);
if (RAttrs.overlaps(AttributeFuncs::typeIncompatible(NewRetTy)))
return false; // Attribute not compatible with transformed value.
}
// If the callsite is an invoke instruction, and the return value is used by
// a PHI node in a successor, we cannot change the return type of the call
// because there is no place to put the cast instruction (without breaking
// the critical edge). Bail out in this case.
if (!Caller->use_empty())
if (InvokeInst *II = dyn_cast<InvokeInst>(Caller))
for (User *U : II->users())
if (PHINode *PN = dyn_cast<PHINode>(U))
if (PN->getParent() == II->getNormalDest() ||
PN->getParent() == II->getUnwindDest())
return false;
}
unsigned NumActualArgs = CS.arg_size();
unsigned NumCommonArgs = std::min(FT->getNumParams(), NumActualArgs);
// Prevent us turning:
// declare void @takes_i32_inalloca(i32* inalloca)
// call void bitcast (void (i32*)* @takes_i32_inalloca to void (i32)*)(i32 0)
//
// into:
// call void @takes_i32_inalloca(i32* null)
//
// Similarly, avoid folding away bitcasts of byval calls.
if (Callee->getAttributes().hasAttrSomewhere(Attribute::InAlloca) ||
Callee->getAttributes().hasAttrSomewhere(Attribute::ByVal))
return false;
CallSite::arg_iterator AI = CS.arg_begin();
for (unsigned i = 0, e = NumCommonArgs; i != e; ++i, ++AI) {
Type *ParamTy = FT->getParamType(i);
Type *ActTy = (*AI)->getType();
if (!CastInst::isBitOrNoopPointerCastable(ActTy, ParamTy, DL))
return false; // Cannot transform this parameter value.
if (AttrBuilder(CallerPAL.getParamAttributes(i + 1), i + 1).
overlaps(AttributeFuncs::typeIncompatible(ParamTy)))
return false; // Attribute not compatible with transformed value.
if (CS.isInAllocaArgument(i))
return false; // Cannot transform to and from inalloca.
// If the parameter is passed as a byval argument, then we have to have a
// sized type and the sized type has to have the same size as the old type.
if (ParamTy != ActTy &&
CallerPAL.getParamAttributes(i + 1).hasAttribute(i + 1,
Attribute::ByVal)) {
PointerType *ParamPTy = dyn_cast<PointerType>(ParamTy);
if (!ParamPTy || !ParamPTy->getElementType()->isSized())
return false;
Type *CurElTy = ActTy->getPointerElementType();
if (DL.getTypeAllocSize(CurElTy) !=
DL.getTypeAllocSize(ParamPTy->getElementType()))
return false;
}
}
if (Callee->isDeclaration()) {
// Do not delete arguments unless we have a function body.
if (FT->getNumParams() < NumActualArgs && !FT->isVarArg())
return false;
// If the callee is just a declaration, don't change the varargsness of the
// call. We don't want to introduce a varargs call where one doesn't
// already exist.
PointerType *APTy = cast<PointerType>(CS.getCalledValue()->getType());
if (FT->isVarArg()!=cast<FunctionType>(APTy->getElementType())->isVarArg())
return false;
// If both the callee and the cast type are varargs, we still have to make
// sure the number of fixed parameters are the same or we have the same
// ABI issues as if we introduce a varargs call.
if (FT->isVarArg() &&
cast<FunctionType>(APTy->getElementType())->isVarArg() &&
FT->getNumParams() !=
cast<FunctionType>(APTy->getElementType())->getNumParams())
return false;
}
if (FT->getNumParams() < NumActualArgs && FT->isVarArg() &&
!CallerPAL.isEmpty())
// In this case we have more arguments than the new function type, but we
// won't be dropping them. Check that these extra arguments have attributes
// that are compatible with being a vararg call argument.
for (unsigned i = CallerPAL.getNumSlots(); i; --i) {
unsigned Index = CallerPAL.getSlotIndex(i - 1);
if (Index <= FT->getNumParams())
break;
// Check if it has an attribute that's incompatible with varargs.
AttributeSet PAttrs = CallerPAL.getSlotAttributes(i - 1);
if (PAttrs.hasAttribute(Index, Attribute::StructRet))
return false;
}
// Okay, we decided that this is a safe thing to do: go ahead and start
// inserting cast instructions as necessary.
std::vector<Value*> Args;
Args.reserve(NumActualArgs);
SmallVector<AttributeSet, 8> attrVec;
attrVec.reserve(NumCommonArgs);
// Get any return attributes.
AttrBuilder RAttrs(CallerPAL, AttributeSet::ReturnIndex);
// If the return value is not being used, the type may not be compatible
// with the existing attributes. Wipe out any problematic attributes.
RAttrs.remove(AttributeFuncs::typeIncompatible(NewRetTy));
// Add the new return attributes.
if (RAttrs.hasAttributes())
attrVec.push_back(AttributeSet::get(Caller->getContext(),
AttributeSet::ReturnIndex, RAttrs));
AI = CS.arg_begin();
for (unsigned i = 0; i != NumCommonArgs; ++i, ++AI) {
Type *ParamTy = FT->getParamType(i);
if ((*AI)->getType() == ParamTy) {
Args.push_back(*AI);
} else {
Args.push_back(Builder->CreateBitOrPointerCast(*AI, ParamTy));
}
// Add any parameter attributes.
AttrBuilder PAttrs(CallerPAL.getParamAttributes(i + 1), i + 1);
if (PAttrs.hasAttributes())
attrVec.push_back(AttributeSet::get(Caller->getContext(), i + 1,
PAttrs));
}
// If the function takes more arguments than the call was taking, add them
// now.
for (unsigned i = NumCommonArgs; i != FT->getNumParams(); ++i)
Args.push_back(Constant::getNullValue(FT->getParamType(i)));
// If we are removing arguments to the function, emit an obnoxious warning.
if (FT->getNumParams() < NumActualArgs) {
// TODO: if (!FT->isVarArg()) this call may be unreachable. PR14722
if (FT->isVarArg()) {
// Add all of the arguments in their promoted form to the arg list.
for (unsigned i = FT->getNumParams(); i != NumActualArgs; ++i, ++AI) {
Type *PTy = getPromotedType((*AI)->getType());
if (PTy != (*AI)->getType()) {
// Must promote to pass through va_arg area!
Instruction::CastOps opcode =
CastInst::getCastOpcode(*AI, false, PTy, false);
Args.push_back(Builder->CreateCast(opcode, *AI, PTy));
} else {
Args.push_back(*AI);
}
// Add any parameter attributes.
AttrBuilder PAttrs(CallerPAL.getParamAttributes(i + 1), i + 1);
if (PAttrs.hasAttributes())
attrVec.push_back(AttributeSet::get(FT->getContext(), i + 1,
PAttrs));
}
}
}
AttributeSet FnAttrs = CallerPAL.getFnAttributes();
if (CallerPAL.hasAttributes(AttributeSet::FunctionIndex))
attrVec.push_back(AttributeSet::get(Callee->getContext(), FnAttrs));
if (NewRetTy->isVoidTy())
Caller->setName(""); // Void type should not have a name.
const AttributeSet &NewCallerPAL = AttributeSet::get(Callee->getContext(),
attrVec);
Instruction *NC;
if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) {
NC = Builder->CreateInvoke(Callee, II->getNormalDest(),
II->getUnwindDest(), Args);
NC->takeName(II);
cast<InvokeInst>(NC)->setCallingConv(II->getCallingConv());
cast<InvokeInst>(NC)->setAttributes(NewCallerPAL);
} else {
CallInst *CI = cast<CallInst>(Caller);
NC = Builder->CreateCall(Callee, Args);
NC->takeName(CI);
if (CI->isTailCall())
cast<CallInst>(NC)->setTailCall();
cast<CallInst>(NC)->setCallingConv(CI->getCallingConv());
cast<CallInst>(NC)->setAttributes(NewCallerPAL);
}
// Insert a cast of the return type as necessary.
Value *NV = NC;
if (OldRetTy != NV->getType() && !Caller->use_empty()) {
if (!NV->getType()->isVoidTy()) {
NV = NC = CastInst::CreateBitOrPointerCast(NC, OldRetTy);
NC->setDebugLoc(Caller->getDebugLoc());
// If this is an invoke instruction, we should insert it after the first
// non-phi, instruction in the normal successor block.
if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) {
BasicBlock::iterator I = II->getNormalDest()->getFirstInsertionPt();
InsertNewInstBefore(NC, *I);
} else {
// Otherwise, it's a call, just insert cast right after the call.
InsertNewInstBefore(NC, *Caller);
}
Worklist.AddUsersToWorkList(*Caller);
} else {
NV = UndefValue::get(Caller->getType());
}
}
if (!Caller->use_empty())
ReplaceInstUsesWith(*Caller, NV);
else if (Caller->hasValueHandle()) {
if (OldRetTy == NV->getType())
ValueHandleBase::ValueIsRAUWd(Caller, NV);
else
// We cannot call ValueIsRAUWd with a different type, and the
// actual tracked value will disappear.
ValueHandleBase::ValueIsDeleted(Caller);
}
EraseInstFromFunction(*Caller);
return true;
}
// transformCallThroughTrampoline - Turn a call to a function created by
// init_trampoline / adjust_trampoline intrinsic pair into a direct call to the
// underlying function.
//
Instruction *
InstCombiner::transformCallThroughTrampoline(CallSite CS,
IntrinsicInst *Tramp) {
Value *Callee = CS.getCalledValue();
PointerType *PTy = cast<PointerType>(Callee->getType());
FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
const AttributeSet &Attrs = CS.getAttributes();
// If the call already has the 'nest' attribute somewhere then give up -
// otherwise 'nest' would occur twice after splicing in the chain.
if (Attrs.hasAttrSomewhere(Attribute::Nest))
return nullptr;
assert(Tramp &&
"transformCallThroughTrampoline called with incorrect CallSite.");
Function *NestF =cast<Function>(Tramp->getArgOperand(1)->stripPointerCasts());
PointerType *NestFPTy = cast<PointerType>(NestF->getType());
FunctionType *NestFTy = cast<FunctionType>(NestFPTy->getElementType());
const AttributeSet &NestAttrs = NestF->getAttributes();
if (!NestAttrs.isEmpty()) {
unsigned NestIdx = 1;
Type *NestTy = nullptr;
AttributeSet NestAttr;
// Look for a parameter marked with the 'nest' attribute.
for (FunctionType::param_iterator I = NestFTy->param_begin(),
E = NestFTy->param_end(); I != E; ++NestIdx, ++I)
if (NestAttrs.hasAttribute(NestIdx, Attribute::Nest)) {
// Record the parameter type and any other attributes.
NestTy = *I;
NestAttr = NestAttrs.getParamAttributes(NestIdx);
break;
}
if (NestTy) {
Instruction *Caller = CS.getInstruction();
std::vector<Value*> NewArgs;
NewArgs.reserve(CS.arg_size() + 1);
SmallVector<AttributeSet, 8> NewAttrs;
NewAttrs.reserve(Attrs.getNumSlots() + 1);
// Insert the nest argument into the call argument list, which may
// mean appending it. Likewise for attributes.
// Add any result attributes.
if (Attrs.hasAttributes(AttributeSet::ReturnIndex))
NewAttrs.push_back(AttributeSet::get(Caller->getContext(),
Attrs.getRetAttributes()));
{
unsigned Idx = 1;
CallSite::arg_iterator I = CS.arg_begin(), E = CS.arg_end();
do {
if (Idx == NestIdx) {
// Add the chain argument and attributes.
Value *NestVal = Tramp->getArgOperand(2);
if (NestVal->getType() != NestTy)
NestVal = Builder->CreateBitCast(NestVal, NestTy, "nest");
NewArgs.push_back(NestVal);
NewAttrs.push_back(AttributeSet::get(Caller->getContext(),
NestAttr));
}
if (I == E)
break;
// Add the original argument and attributes.
NewArgs.push_back(*I);
AttributeSet Attr = Attrs.getParamAttributes(Idx);
if (Attr.hasAttributes(Idx)) {
AttrBuilder B(Attr, Idx);
NewAttrs.push_back(AttributeSet::get(Caller->getContext(),
Idx + (Idx >= NestIdx), B));
}
++Idx, ++I;
} while (1);
}
// Add any function attributes.
if (Attrs.hasAttributes(AttributeSet::FunctionIndex))
NewAttrs.push_back(AttributeSet::get(FTy->getContext(),
Attrs.getFnAttributes()));
// The trampoline may have been bitcast to a bogus type (FTy).
// Handle this by synthesizing a new function type, equal to FTy
// with the chain parameter inserted.
std::vector<Type*> NewTypes;
NewTypes.reserve(FTy->getNumParams()+1);
// Insert the chain's type into the list of parameter types, which may
// mean appending it.
{
unsigned Idx = 1;
FunctionType::param_iterator I = FTy->param_begin(),
E = FTy->param_end();
do {
if (Idx == NestIdx)
// Add the chain's type.
NewTypes.push_back(NestTy);
if (I == E)
break;
// Add the original type.
NewTypes.push_back(*I);
++Idx, ++I;
} while (1);
}
// Replace the trampoline call with a direct call. Let the generic
// code sort out any function type mismatches.
FunctionType *NewFTy = FunctionType::get(FTy->getReturnType(), NewTypes,
FTy->isVarArg());
Constant *NewCallee =
NestF->getType() == PointerType::getUnqual(NewFTy) ?
NestF : ConstantExpr::getBitCast(NestF,
PointerType::getUnqual(NewFTy));
const AttributeSet &NewPAL =
AttributeSet::get(FTy->getContext(), NewAttrs);
Instruction *NewCaller;
if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) {
NewCaller = InvokeInst::Create(NewCallee,
II->getNormalDest(), II->getUnwindDest(),
NewArgs);
cast<InvokeInst>(NewCaller)->setCallingConv(II->getCallingConv());
cast<InvokeInst>(NewCaller)->setAttributes(NewPAL);
} else {
NewCaller = CallInst::Create(NewCallee, NewArgs);
if (cast<CallInst>(Caller)->isTailCall())
cast<CallInst>(NewCaller)->setTailCall();
cast<CallInst>(NewCaller)->
setCallingConv(cast<CallInst>(Caller)->getCallingConv());
cast<CallInst>(NewCaller)->setAttributes(NewPAL);
}
return NewCaller;
}
}
// Replace the trampoline call with a direct call. Since there is no 'nest'
// parameter, there is no need to adjust the argument list. Let the generic
// code sort out any function type mismatches.
Constant *NewCallee =
NestF->getType() == PTy ? NestF :
ConstantExpr::getBitCast(NestF, PTy);
CS.setCalledFunction(NewCallee);
return CS.getInstruction();
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/CMakeLists.txt | add_llvm_library(LLVMInstCombine
InstructionCombining.cpp
InstCombineAddSub.cpp
InstCombineAndOrXor.cpp
InstCombineCalls.cpp
InstCombineCasts.cpp
InstCombineCompares.cpp
InstCombineLoadStoreAlloca.cpp
InstCombineMulDivRem.cpp
InstCombinePHI.cpp
InstCombineSelect.cpp
InstCombineShifts.cpp
InstCombineSimplifyDemanded.cpp
InstCombineVectorOps.cpp
ADDITIONAL_HEADER_DIRS
${LLVM_MAIN_INCLUDE_DIR}/llvm/Transforms
${LLVM_MAIN_INCLUDE_DIR}/llvm/Transforms/InstCombine
)
add_dependencies(LLVMInstCombine intrinsics_gen)
target_link_libraries(LLVMInstCombine PUBLIC LLVMDXIL) # HLSL Change |
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/LLVMBuild.txt | ;===- ./lib/Transforms/InstCombine/LLVMBuild.txt ---------------*- Conf -*--===;
;
; The LLVM Compiler Infrastructure
;
; This file is distributed under the University of Illinois Open Source
; License. See LICENSE.TXT for details.
;
;===------------------------------------------------------------------------===;
;
; This is an LLVMBuild description file for the components in this subdirectory.
;
; For more information on the LLVMBuild system, please see:
;
; http://llvm.org/docs/LLVMBuild.html
;
;===------------------------------------------------------------------------===;
[component_0]
type = Library
name = InstCombine
parent = Transforms
required_libraries = Analysis Core Support TransformUtils
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp | //===- InstCombineMulDivRem.cpp -------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the visit functions for mul, fmul, sdiv, udiv, fdiv,
// srem, urem, frem.
//
//===----------------------------------------------------------------------===//
#include "InstCombineInternal.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/PatternMatch.h"
using namespace llvm;
using namespace PatternMatch;
#define DEBUG_TYPE "instcombine"
/// simplifyValueKnownNonZero - The specific integer value is used in a context
/// where it is known to be non-zero. If this allows us to simplify the
/// computation, do so and return the new operand, otherwise return null.
static Value *simplifyValueKnownNonZero(Value *V, InstCombiner &IC,
Instruction &CxtI) {
// If V has multiple uses, then we would have to do more analysis to determine
// if this is safe. For example, the use could be in dynamically unreached
// code.
if (!V->hasOneUse()) return nullptr;
bool MadeChange = false;
// ((1 << A) >>u B) --> (1 << (A-B))
// Because V cannot be zero, we know that B is less than A.
Value *A = nullptr, *B = nullptr, *One = nullptr;
if (match(V, m_LShr(m_OneUse(m_Shl(m_Value(One), m_Value(A))), m_Value(B))) &&
match(One, m_One())) {
A = IC.Builder->CreateSub(A, B);
return IC.Builder->CreateShl(One, A);
}
// (PowerOfTwo >>u B) --> isExact since shifting out the result would make it
// inexact. Similarly for <<.
if (BinaryOperator *I = dyn_cast<BinaryOperator>(V))
if (I->isLogicalShift() &&
isKnownToBeAPowerOfTwo(I->getOperand(0), IC.getDataLayout(), false, 0,
IC.getAssumptionCache(), &CxtI,
IC.getDominatorTree())) {
// We know that this is an exact/nuw shift and that the input is a
// non-zero context as well.
if (Value *V2 = simplifyValueKnownNonZero(I->getOperand(0), IC, CxtI)) {
I->setOperand(0, V2);
MadeChange = true;
}
if (I->getOpcode() == Instruction::LShr && !I->isExact()) {
I->setIsExact();
MadeChange = true;
}
if (I->getOpcode() == Instruction::Shl && !I->hasNoUnsignedWrap()) {
I->setHasNoUnsignedWrap();
MadeChange = true;
}
}
// TODO: Lots more we could do here:
// If V is a phi node, we can call this on each of its operands.
// "select cond, X, 0" can simplify to "X".
return MadeChange ? V : nullptr;
}
/// MultiplyOverflows - True if the multiply can not be expressed in an int
/// this size.
static bool MultiplyOverflows(const APInt &C1, const APInt &C2, APInt &Product,
bool IsSigned) {
bool Overflow;
if (IsSigned)
Product = C1.smul_ov(C2, Overflow);
else
Product = C1.umul_ov(C2, Overflow);
return Overflow;
}
/// \brief True if C2 is a multiple of C1. Quotient contains C2/C1.
static bool IsMultiple(const APInt &C1, const APInt &C2, APInt &Quotient,
bool IsSigned) {
assert(C1.getBitWidth() == C2.getBitWidth() &&
"Inconsistent width of constants!");
APInt Remainder(C1.getBitWidth(), /*Val=*/0ULL, IsSigned);
if (IsSigned)
APInt::sdivrem(C1, C2, Quotient, Remainder);
else
APInt::udivrem(C1, C2, Quotient, Remainder);
return Remainder.isMinValue();
}
/// \brief A helper routine of InstCombiner::visitMul().
///
/// If C is a vector of known powers of 2, then this function returns
/// a new vector obtained from C replacing each element with its logBase2.
/// Return a null pointer otherwise.
static Constant *getLogBase2Vector(ConstantDataVector *CV) {
const APInt *IVal;
SmallVector<Constant *, 4> Elts;
for (unsigned I = 0, E = CV->getNumElements(); I != E; ++I) {
Constant *Elt = CV->getElementAsConstant(I);
if (!match(Elt, m_APInt(IVal)) || !IVal->isPowerOf2())
return nullptr;
Elts.push_back(ConstantInt::get(Elt->getType(), IVal->logBase2()));
}
return ConstantVector::get(Elts);
}
/// \brief Return true if we can prove that:
/// (mul LHS, RHS) === (mul nsw LHS, RHS)
bool InstCombiner::WillNotOverflowSignedMul(Value *LHS, Value *RHS,
Instruction &CxtI) {
// Multiplying n * m significant bits yields a result of n + m significant
// bits. If the total number of significant bits does not exceed the
// result bit width (minus 1), there is no overflow.
// This means if we have enough leading sign bits in the operands
// we can guarantee that the result does not overflow.
// Ref: "Hacker's Delight" by Henry Warren
unsigned BitWidth = LHS->getType()->getScalarSizeInBits();
// Note that underestimating the number of sign bits gives a more
// conservative answer.
unsigned SignBits =
ComputeNumSignBits(LHS, 0, &CxtI) + ComputeNumSignBits(RHS, 0, &CxtI);
// First handle the easy case: if we have enough sign bits there's
// definitely no overflow.
if (SignBits > BitWidth + 1)
return true;
// There are two ambiguous cases where there can be no overflow:
// SignBits == BitWidth + 1 and
// SignBits == BitWidth
// The second case is difficult to check, therefore we only handle the
// first case.
if (SignBits == BitWidth + 1) {
// It overflows only when both arguments are negative and the true
// product is exactly the minimum negative number.
// E.g. mul i16 with 17 sign bits: 0xff00 * 0xff80 = 0x8000
// For simplicity we just check if at least one side is not negative.
bool LHSNonNegative, LHSNegative;
bool RHSNonNegative, RHSNegative;
ComputeSignBit(LHS, LHSNonNegative, LHSNegative, /*Depth=*/0, &CxtI);
ComputeSignBit(RHS, RHSNonNegative, RHSNegative, /*Depth=*/0, &CxtI);
if (LHSNonNegative || RHSNonNegative)
return true;
}
return false;
}
Instruction *InstCombiner::visitMul(BinaryOperator &I) {
bool Changed = SimplifyAssociativeOrCommutative(I);
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifyMulInst(Op0, Op1, DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifyUsingDistributiveLaws(I))
return ReplaceInstUsesWith(I, V);
// X * -1 == 0 - X
if (match(Op1, m_AllOnes())) {
BinaryOperator *BO = BinaryOperator::CreateNeg(Op0, I.getName());
if (I.hasNoSignedWrap())
BO->setHasNoSignedWrap();
return BO;
}
// Also allow combining multiply instructions on vectors.
{
Value *NewOp;
Constant *C1, *C2;
const APInt *IVal;
if (match(&I, m_Mul(m_Shl(m_Value(NewOp), m_Constant(C2)),
m_Constant(C1))) &&
match(C1, m_APInt(IVal))) {
// ((X << C2)*C1) == (X * (C1 << C2))
Constant *Shl = ConstantExpr::getShl(C1, C2);
BinaryOperator *Mul = cast<BinaryOperator>(I.getOperand(0));
BinaryOperator *BO = BinaryOperator::CreateMul(NewOp, Shl);
if (I.hasNoUnsignedWrap() && Mul->hasNoUnsignedWrap())
BO->setHasNoUnsignedWrap();
if (I.hasNoSignedWrap() && Mul->hasNoSignedWrap() &&
Shl->isNotMinSignedValue())
BO->setHasNoSignedWrap();
return BO;
}
if (match(&I, m_Mul(m_Value(NewOp), m_Constant(C1)))) {
Constant *NewCst = nullptr;
if (match(C1, m_APInt(IVal)) && IVal->isPowerOf2())
// Replace X*(2^C) with X << C, where C is either a scalar or a splat.
NewCst = ConstantInt::get(NewOp->getType(), IVal->logBase2());
else if (ConstantDataVector *CV = dyn_cast<ConstantDataVector>(C1))
// Replace X*(2^C) with X << C, where C is a vector of known
// constant powers of 2.
NewCst = getLogBase2Vector(CV);
if (NewCst) {
unsigned Width = NewCst->getType()->getPrimitiveSizeInBits();
BinaryOperator *Shl = BinaryOperator::CreateShl(NewOp, NewCst);
if (I.hasNoUnsignedWrap())
Shl->setHasNoUnsignedWrap();
if (I.hasNoSignedWrap()) {
uint64_t V;
if (match(NewCst, m_ConstantInt(V)) && V != Width - 1)
Shl->setHasNoSignedWrap();
}
return Shl;
}
}
}
if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
// (Y - X) * (-(2**n)) -> (X - Y) * (2**n), for positive nonzero n
// (Y + const) * (-(2**n)) -> (-constY) * (2**n), for positive nonzero n
// The "* (2**n)" thus becomes a potential shifting opportunity.
{
const APInt & Val = CI->getValue();
const APInt &PosVal = Val.abs();
if (Val.isNegative() && PosVal.isPowerOf2()) {
Value *X = nullptr, *Y = nullptr;
if (Op0->hasOneUse()) {
ConstantInt *C1;
Value *Sub = nullptr;
if (match(Op0, m_Sub(m_Value(Y), m_Value(X))))
Sub = Builder->CreateSub(X, Y, "suba");
else if (match(Op0, m_Add(m_Value(Y), m_ConstantInt(C1))))
Sub = Builder->CreateSub(Builder->CreateNeg(C1), Y, "subc");
if (Sub)
return
BinaryOperator::CreateMul(Sub,
ConstantInt::get(Y->getType(), PosVal));
}
}
}
}
// Simplify mul instructions with a constant RHS.
if (isa<Constant>(Op1)) {
// Try to fold constant mul into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (isa<PHINode>(Op0))
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
// Canonicalize (X+C1)*CI -> X*CI+C1*CI.
{
Value *X;
Constant *C1;
if (match(Op0, m_OneUse(m_Add(m_Value(X), m_Constant(C1))))) {
Value *Mul = Builder->CreateMul(C1, Op1);
// Only go forward with the transform if C1*CI simplifies to a tidier
// constant.
if (!match(Mul, m_Mul(m_Value(), m_Value())))
return BinaryOperator::CreateAdd(Builder->CreateMul(X, Op1), Mul);
}
}
}
if (Value *Op0v = dyn_castNegVal(Op0)) { // -X * -Y = X*Y
if (Value *Op1v = dyn_castNegVal(Op1)) {
BinaryOperator *BO = BinaryOperator::CreateMul(Op0v, Op1v);
if (I.hasNoSignedWrap() &&
match(Op0, m_NSWSub(m_Value(), m_Value())) &&
match(Op1, m_NSWSub(m_Value(), m_Value())))
BO->setHasNoSignedWrap();
return BO;
}
}
// (X / Y) * Y = X - (X % Y)
// (X / Y) * -Y = (X % Y) - X
{
Value *Op1C = Op1;
BinaryOperator *BO = dyn_cast<BinaryOperator>(Op0);
if (!BO ||
(BO->getOpcode() != Instruction::UDiv &&
BO->getOpcode() != Instruction::SDiv)) {
Op1C = Op0;
BO = dyn_cast<BinaryOperator>(Op1);
}
Value *Neg = dyn_castNegVal(Op1C);
if (BO && BO->hasOneUse() &&
(BO->getOperand(1) == Op1C || BO->getOperand(1) == Neg) &&
(BO->getOpcode() == Instruction::UDiv ||
BO->getOpcode() == Instruction::SDiv)) {
Value *Op0BO = BO->getOperand(0), *Op1BO = BO->getOperand(1);
// If the division is exact, X % Y is zero, so we end up with X or -X.
if (PossiblyExactOperator *SDiv = dyn_cast<PossiblyExactOperator>(BO))
if (SDiv->isExact()) {
if (Op1BO == Op1C)
return ReplaceInstUsesWith(I, Op0BO);
return BinaryOperator::CreateNeg(Op0BO);
}
Value *Rem;
if (BO->getOpcode() == Instruction::UDiv)
Rem = Builder->CreateURem(Op0BO, Op1BO);
else
Rem = Builder->CreateSRem(Op0BO, Op1BO);
Rem->takeName(BO);
if (Op1BO == Op1C)
return BinaryOperator::CreateSub(Op0BO, Rem);
return BinaryOperator::CreateSub(Rem, Op0BO);
}
}
/// i1 mul -> i1 and.
if (I.getType()->getScalarType()->isIntegerTy(1))
return BinaryOperator::CreateAnd(Op0, Op1);
// X*(1 << Y) --> X << Y
// (1 << Y)*X --> X << Y
{
Value *Y;
BinaryOperator *BO = nullptr;
bool ShlNSW = false;
if (match(Op0, m_Shl(m_One(), m_Value(Y)))) {
BO = BinaryOperator::CreateShl(Op1, Y);
ShlNSW = cast<ShlOperator>(Op0)->hasNoSignedWrap();
} else if (match(Op1, m_Shl(m_One(), m_Value(Y)))) {
BO = BinaryOperator::CreateShl(Op0, Y);
ShlNSW = cast<ShlOperator>(Op1)->hasNoSignedWrap();
}
if (BO) {
if (I.hasNoUnsignedWrap())
BO->setHasNoUnsignedWrap();
if (I.hasNoSignedWrap() && ShlNSW)
BO->setHasNoSignedWrap();
return BO;
}
}
// If one of the operands of the multiply is a cast from a boolean value, then
// we know the bool is either zero or one, so this is a 'masking' multiply.
// X * Y (where Y is 0 or 1) -> X & (0-Y)
if (!I.getType()->isVectorTy()) {
// -2 is "-1 << 1" so it is all bits set except the low one.
APInt Negative2(I.getType()->getPrimitiveSizeInBits(), (uint64_t)-2, true);
Value *BoolCast = nullptr, *OtherOp = nullptr;
if (MaskedValueIsZero(Op0, Negative2, 0, &I))
BoolCast = Op0, OtherOp = Op1;
else if (MaskedValueIsZero(Op1, Negative2, 0, &I))
BoolCast = Op1, OtherOp = Op0;
if (BoolCast) {
Value *V = Builder->CreateSub(Constant::getNullValue(I.getType()),
BoolCast);
return BinaryOperator::CreateAnd(V, OtherOp);
}
}
if (!I.hasNoSignedWrap() && WillNotOverflowSignedMul(Op0, Op1, I)) {
Changed = true;
I.setHasNoSignedWrap(true);
}
if (!I.hasNoUnsignedWrap() &&
computeOverflowForUnsignedMul(Op0, Op1, &I) ==
OverflowResult::NeverOverflows) {
Changed = true;
I.setHasNoUnsignedWrap(true);
}
return Changed ? &I : nullptr;
}
/// Detect pattern log2(Y * 0.5) with corresponding fast math flags.
static void detectLog2OfHalf(Value *&Op, Value *&Y, IntrinsicInst *&Log2) {
if (!Op->hasOneUse())
return;
IntrinsicInst *II = dyn_cast<IntrinsicInst>(Op);
if (!II)
return;
if (II->getIntrinsicID() != Intrinsic::log2 || !II->hasUnsafeAlgebra())
return;
Log2 = II;
Value *OpLog2Of = II->getArgOperand(0);
if (!OpLog2Of->hasOneUse())
return;
Instruction *I = dyn_cast<Instruction>(OpLog2Of);
if (!I)
return;
if (I->getOpcode() != Instruction::FMul || !I->hasUnsafeAlgebra())
return;
if (match(I->getOperand(0), m_SpecificFP(0.5)))
Y = I->getOperand(1);
else if (match(I->getOperand(1), m_SpecificFP(0.5)))
Y = I->getOperand(0);
}
static bool isFiniteNonZeroFp(Constant *C) {
if (C->getType()->isVectorTy()) {
for (unsigned I = 0, E = C->getType()->getVectorNumElements(); I != E;
++I) {
ConstantFP *CFP = dyn_cast_or_null<ConstantFP>(C->getAggregateElement(I));
if (!CFP || !CFP->getValueAPF().isFiniteNonZero())
return false;
}
return true;
}
return isa<ConstantFP>(C) &&
cast<ConstantFP>(C)->getValueAPF().isFiniteNonZero();
}
static bool isNormalFp(Constant *C) {
if (C->getType()->isVectorTy()) {
for (unsigned I = 0, E = C->getType()->getVectorNumElements(); I != E;
++I) {
ConstantFP *CFP = dyn_cast_or_null<ConstantFP>(C->getAggregateElement(I));
if (!CFP || !CFP->getValueAPF().isNormal())
return false;
}
return true;
}
return isa<ConstantFP>(C) && cast<ConstantFP>(C)->getValueAPF().isNormal();
}
/// Helper function of InstCombiner::visitFMul(BinaryOperator(). It returns
/// true iff the given value is FMul or FDiv with one and only one operand
/// being a normal constant (i.e. not Zero/NaN/Infinity).
static bool isFMulOrFDivWithConstant(Value *V) {
Instruction *I = dyn_cast<Instruction>(V);
if (!I || (I->getOpcode() != Instruction::FMul &&
I->getOpcode() != Instruction::FDiv))
return false;
Constant *C0 = dyn_cast<Constant>(I->getOperand(0));
Constant *C1 = dyn_cast<Constant>(I->getOperand(1));
if (C0 && C1)
return false;
return (C0 && isFiniteNonZeroFp(C0)) || (C1 && isFiniteNonZeroFp(C1));
}
/// foldFMulConst() is a helper routine of InstCombiner::visitFMul().
/// The input \p FMulOrDiv is a FMul/FDiv with one and only one operand
/// being a constant (i.e. isFMulOrFDivWithConstant(FMulOrDiv) == true).
/// This function is to simplify "FMulOrDiv * C" and returns the
/// resulting expression. Note that this function could return NULL in
/// case the constants cannot be folded into a normal floating-point.
///
Value *InstCombiner::foldFMulConst(Instruction *FMulOrDiv, Constant *C,
Instruction *InsertBefore) {
assert(isFMulOrFDivWithConstant(FMulOrDiv) && "V is invalid");
Value *Opnd0 = FMulOrDiv->getOperand(0);
Value *Opnd1 = FMulOrDiv->getOperand(1);
Constant *C0 = dyn_cast<Constant>(Opnd0);
Constant *C1 = dyn_cast<Constant>(Opnd1);
BinaryOperator *R = nullptr;
// (X * C0) * C => X * (C0*C)
if (FMulOrDiv->getOpcode() == Instruction::FMul) {
Constant *F = ConstantExpr::getFMul(C1 ? C1 : C0, C);
if (isNormalFp(F))
R = BinaryOperator::CreateFMul(C1 ? Opnd0 : Opnd1, F);
} else {
if (C0) {
// (C0 / X) * C => (C0 * C) / X
if (FMulOrDiv->hasOneUse()) {
// It would otherwise introduce another div.
Constant *F = ConstantExpr::getFMul(C0, C);
if (isNormalFp(F))
R = BinaryOperator::CreateFDiv(F, Opnd1);
}
} else {
// (X / C1) * C => X * (C/C1) if C/C1 is not a denormal
Constant *F = ConstantExpr::getFDiv(C, C1);
if (isNormalFp(F)) {
R = BinaryOperator::CreateFMul(Opnd0, F);
} else {
// (X / C1) * C => X / (C1/C)
Constant *F = ConstantExpr::getFDiv(C1, C);
if (isNormalFp(F))
R = BinaryOperator::CreateFDiv(Opnd0, F);
}
}
}
if (R) {
R->setHasUnsafeAlgebra(true);
InsertNewInstWith(R, *InsertBefore);
}
return R;
}
Instruction *InstCombiner::visitFMul(BinaryOperator &I) {
bool Changed = SimplifyAssociativeOrCommutative(I);
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (isa<Constant>(Op0))
std::swap(Op0, Op1);
if (Value *V =
SimplifyFMulInst(Op0, Op1, I.getFastMathFlags(), DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
bool AllowReassociate = I.hasUnsafeAlgebra();
// Simplify mul instructions with a constant RHS.
if (isa<Constant>(Op1)) {
// Try to fold constant mul into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (isa<PHINode>(Op0))
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
// (fmul X, -1.0) --> (fsub -0.0, X)
if (match(Op1, m_SpecificFP(-1.0))) {
Constant *NegZero = ConstantFP::getNegativeZero(Op1->getType());
Instruction *RI = BinaryOperator::CreateFSub(NegZero, Op0);
RI->copyFastMathFlags(&I);
return RI;
}
Constant *C = cast<Constant>(Op1);
if (AllowReassociate && isFiniteNonZeroFp(C)) {
// Let MDC denote an expression in one of these forms:
// X * C, C/X, X/C, where C is a constant.
//
// Try to simplify "MDC * Constant"
if (isFMulOrFDivWithConstant(Op0))
if (Value *V = foldFMulConst(cast<Instruction>(Op0), C, &I))
return ReplaceInstUsesWith(I, V);
// (MDC +/- C1) * C => (MDC * C) +/- (C1 * C)
Instruction *FAddSub = dyn_cast<Instruction>(Op0);
if (FAddSub &&
(FAddSub->getOpcode() == Instruction::FAdd ||
FAddSub->getOpcode() == Instruction::FSub)) {
Value *Opnd0 = FAddSub->getOperand(0);
Value *Opnd1 = FAddSub->getOperand(1);
Constant *C0 = dyn_cast<Constant>(Opnd0);
Constant *C1 = dyn_cast<Constant>(Opnd1);
bool Swap = false;
if (C0) {
std::swap(C0, C1);
std::swap(Opnd0, Opnd1);
Swap = true;
}
if (C1 && isFiniteNonZeroFp(C1) && isFMulOrFDivWithConstant(Opnd0)) {
Value *M1 = ConstantExpr::getFMul(C1, C);
Value *M0 = isNormalFp(cast<Constant>(M1)) ?
foldFMulConst(cast<Instruction>(Opnd0), C, &I) :
nullptr;
if (M0 && M1) {
if (Swap && FAddSub->getOpcode() == Instruction::FSub)
std::swap(M0, M1);
Instruction *RI = (FAddSub->getOpcode() == Instruction::FAdd)
? BinaryOperator::CreateFAdd(M0, M1)
: BinaryOperator::CreateFSub(M0, M1);
RI->copyFastMathFlags(&I);
return RI;
}
}
}
}
}
// sqrt(X) * sqrt(X) -> X
if (AllowReassociate && (Op0 == Op1))
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(Op0))
if (II->getIntrinsicID() == Intrinsic::sqrt)
return ReplaceInstUsesWith(I, II->getOperand(0));
// Under unsafe algebra do:
// X * log2(0.5*Y) = X*log2(Y) - X
if (AllowReassociate) {
Value *OpX = nullptr;
Value *OpY = nullptr;
IntrinsicInst *Log2;
detectLog2OfHalf(Op0, OpY, Log2);
if (OpY) {
OpX = Op1;
} else {
detectLog2OfHalf(Op1, OpY, Log2);
if (OpY) {
OpX = Op0;
}
}
// if pattern detected emit alternate sequence
if (OpX && OpY) {
BuilderTy::FastMathFlagGuard Guard(*Builder);
Builder->SetFastMathFlags(Log2->getFastMathFlags());
Log2->setArgOperand(0, OpY);
Value *FMulVal = Builder->CreateFMul(OpX, Log2);
Value *FSub = Builder->CreateFSub(FMulVal, OpX);
FSub->takeName(&I);
return ReplaceInstUsesWith(I, FSub);
}
}
// Handle symmetric situation in a 2-iteration loop
Value *Opnd0 = Op0;
Value *Opnd1 = Op1;
for (int i = 0; i < 2; i++) {
bool IgnoreZeroSign = I.hasNoSignedZeros();
if (BinaryOperator::isFNeg(Opnd0, IgnoreZeroSign)) {
BuilderTy::FastMathFlagGuard Guard(*Builder);
Builder->SetFastMathFlags(I.getFastMathFlags());
Value *N0 = dyn_castFNegVal(Opnd0, IgnoreZeroSign);
Value *N1 = dyn_castFNegVal(Opnd1, IgnoreZeroSign);
// -X * -Y => X*Y
if (N1) {
Value *FMul = Builder->CreateFMul(N0, N1);
FMul->takeName(&I);
return ReplaceInstUsesWith(I, FMul);
}
if (Opnd0->hasOneUse()) {
// -X * Y => -(X*Y) (Promote negation as high as possible)
Value *T = Builder->CreateFMul(N0, Opnd1);
Value *Neg = Builder->CreateFNeg(T);
Neg->takeName(&I);
return ReplaceInstUsesWith(I, Neg);
}
}
// (X*Y) * X => (X*X) * Y where Y != X
// The purpose is two-fold:
// 1) to form a power expression (of X).
// 2) potentially shorten the critical path: After transformation, the
// latency of the instruction Y is amortized by the expression of X*X,
// and therefore Y is in a "less critical" position compared to what it
// was before the transformation.
//
if (AllowReassociate) {
Value *Opnd0_0, *Opnd0_1;
if (Opnd0->hasOneUse() &&
match(Opnd0, m_FMul(m_Value(Opnd0_0), m_Value(Opnd0_1)))) {
Value *Y = nullptr;
if (Opnd0_0 == Opnd1 && Opnd0_1 != Opnd1)
Y = Opnd0_1;
else if (Opnd0_1 == Opnd1 && Opnd0_0 != Opnd1)
Y = Opnd0_0;
if (Y) {
BuilderTy::FastMathFlagGuard Guard(*Builder);
Builder->SetFastMathFlags(I.getFastMathFlags());
Value *T = Builder->CreateFMul(Opnd1, Opnd1);
Value *R = Builder->CreateFMul(T, Y);
R->takeName(&I);
return ReplaceInstUsesWith(I, R);
}
}
}
if (!isa<Constant>(Op1))
std::swap(Opnd0, Opnd1);
else
break;
}
return Changed ? &I : nullptr;
}
/// SimplifyDivRemOfSelect - Try to fold a divide or remainder of a select
/// instruction.
bool InstCombiner::SimplifyDivRemOfSelect(BinaryOperator &I) {
SelectInst *SI = cast<SelectInst>(I.getOperand(1));
// div/rem X, (Cond ? 0 : Y) -> div/rem X, Y
int NonNullOperand = -1;
if (Constant *ST = dyn_cast<Constant>(SI->getOperand(1)))
if (ST->isNullValue())
NonNullOperand = 2;
// div/rem X, (Cond ? Y : 0) -> div/rem X, Y
if (Constant *ST = dyn_cast<Constant>(SI->getOperand(2)))
if (ST->isNullValue())
NonNullOperand = 1;
if (NonNullOperand == -1)
return false;
Value *SelectCond = SI->getOperand(0);
// Change the div/rem to use 'Y' instead of the select.
I.setOperand(1, SI->getOperand(NonNullOperand));
// Okay, we know we replace the operand of the div/rem with 'Y' with no
// problem. However, the select, or the condition of the select may have
// multiple uses. Based on our knowledge that the operand must be non-zero,
// propagate the known value for the select into other uses of it, and
// propagate a known value of the condition into its other users.
// If the select and condition only have a single use, don't bother with this,
// early exit.
if (SI->use_empty() && SelectCond->hasOneUse())
return true;
// Scan the current block backward, looking for other uses of SI.
BasicBlock::iterator BBI = &I, BBFront = I.getParent()->begin();
while (BBI != BBFront) {
--BBI;
// If we found a call to a function, we can't assume it will return, so
// information from below it cannot be propagated above it.
if (isa<CallInst>(BBI) && !isa<IntrinsicInst>(BBI))
break;
// Replace uses of the select or its condition with the known values.
for (Instruction::op_iterator I = BBI->op_begin(), E = BBI->op_end();
I != E; ++I) {
if (*I == SI) {
*I = SI->getOperand(NonNullOperand);
Worklist.Add(BBI);
} else if (*I == SelectCond) {
*I = Builder->getInt1(NonNullOperand == 1);
Worklist.Add(BBI);
}
}
// If we past the instruction, quit looking for it.
if (&*BBI == SI)
SI = nullptr;
if (&*BBI == SelectCond)
SelectCond = nullptr;
// If we ran out of things to eliminate, break out of the loop.
if (!SelectCond && !SI)
break;
}
return true;
}
/// This function implements the transforms common to both integer division
/// instructions (udiv and sdiv). It is called by the visitors to those integer
/// division instructions.
/// @brief Common integer divide transforms
Instruction *InstCombiner::commonIDivTransforms(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
// The RHS is known non-zero.
if (Value *V = simplifyValueKnownNonZero(I.getOperand(1), *this, I)) {
I.setOperand(1, V);
return &I;
}
// Handle cases involving: [su]div X, (select Cond, Y, Z)
// This does not apply for fdiv.
if (isa<SelectInst>(Op1) && SimplifyDivRemOfSelect(I))
return &I;
if (Instruction *LHS = dyn_cast<Instruction>(Op0)) {
const APInt *C2;
if (match(Op1, m_APInt(C2))) {
Value *X;
const APInt *C1;
bool IsSigned = I.getOpcode() == Instruction::SDiv;
// (X / C1) / C2 -> X / (C1*C2)
if ((IsSigned && match(LHS, m_SDiv(m_Value(X), m_APInt(C1)))) ||
(!IsSigned && match(LHS, m_UDiv(m_Value(X), m_APInt(C1))))) {
APInt Product(C1->getBitWidth(), /*Val=*/0ULL, IsSigned);
if (!MultiplyOverflows(*C1, *C2, Product, IsSigned))
return BinaryOperator::Create(I.getOpcode(), X,
ConstantInt::get(I.getType(), Product));
}
if ((IsSigned && match(LHS, m_NSWMul(m_Value(X), m_APInt(C1)))) ||
(!IsSigned && match(LHS, m_NUWMul(m_Value(X), m_APInt(C1))))) {
APInt Quotient(C1->getBitWidth(), /*Val=*/0ULL, IsSigned);
// (X * C1) / C2 -> X / (C2 / C1) if C2 is a multiple of C1.
if (IsMultiple(*C2, *C1, Quotient, IsSigned)) {
BinaryOperator *BO = BinaryOperator::Create(
I.getOpcode(), X, ConstantInt::get(X->getType(), Quotient));
BO->setIsExact(I.isExact());
return BO;
}
// (X * C1) / C2 -> X * (C1 / C2) if C1 is a multiple of C2.
if (IsMultiple(*C1, *C2, Quotient, IsSigned)) {
BinaryOperator *BO = BinaryOperator::Create(
Instruction::Mul, X, ConstantInt::get(X->getType(), Quotient));
BO->setHasNoUnsignedWrap(
!IsSigned &&
cast<OverflowingBinaryOperator>(LHS)->hasNoUnsignedWrap());
BO->setHasNoSignedWrap(
cast<OverflowingBinaryOperator>(LHS)->hasNoSignedWrap());
return BO;
}
}
if ((IsSigned && match(LHS, m_NSWShl(m_Value(X), m_APInt(C1))) &&
*C1 != C1->getBitWidth() - 1) ||
(!IsSigned && match(LHS, m_NUWShl(m_Value(X), m_APInt(C1))))) {
APInt Quotient(C1->getBitWidth(), /*Val=*/0ULL, IsSigned);
APInt C1Shifted = APInt::getOneBitSet(
C1->getBitWidth(), static_cast<unsigned>(C1->getLimitedValue()));
// (X << C1) / C2 -> X / (C2 >> C1) if C2 is a multiple of C1.
if (IsMultiple(*C2, C1Shifted, Quotient, IsSigned)) {
BinaryOperator *BO = BinaryOperator::Create(
I.getOpcode(), X, ConstantInt::get(X->getType(), Quotient));
BO->setIsExact(I.isExact());
return BO;
}
// (X << C1) / C2 -> X * (C2 >> C1) if C1 is a multiple of C2.
if (IsMultiple(C1Shifted, *C2, Quotient, IsSigned)) {
BinaryOperator *BO = BinaryOperator::Create(
Instruction::Mul, X, ConstantInt::get(X->getType(), Quotient));
BO->setHasNoUnsignedWrap(
!IsSigned &&
cast<OverflowingBinaryOperator>(LHS)->hasNoUnsignedWrap());
BO->setHasNoSignedWrap(
cast<OverflowingBinaryOperator>(LHS)->hasNoSignedWrap());
return BO;
}
}
if (*C2 != 0) { // avoid X udiv 0
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (isa<PHINode>(Op0))
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
}
}
}
if (ConstantInt *One = dyn_cast<ConstantInt>(Op0)) {
if (One->isOne() && !I.getType()->isIntegerTy(1)) {
bool isSigned = I.getOpcode() == Instruction::SDiv;
if (isSigned) {
// If Op1 is 0 then it's undefined behaviour, if Op1 is 1 then the
// result is one, if Op1 is -1 then the result is minus one, otherwise
// it's zero.
Value *Inc = Builder->CreateAdd(Op1, One);
Value *Cmp = Builder->CreateICmpULT(
Inc, ConstantInt::get(I.getType(), 3));
return SelectInst::Create(Cmp, Op1, ConstantInt::get(I.getType(), 0));
} else {
// If Op1 is 0 then it's undefined behaviour. If Op1 is 1 then the
// result is one, otherwise it's zero.
return new ZExtInst(Builder->CreateICmpEQ(Op1, One), I.getType());
}
}
}
// See if we can fold away this div instruction.
if (SimplifyDemandedInstructionBits(I))
return &I;
// (X - (X rem Y)) / Y -> X / Y; usually originates as ((X / Y) * Y) / Y
Value *X = nullptr, *Z = nullptr;
if (match(Op0, m_Sub(m_Value(X), m_Value(Z)))) { // (X - Z) / Y; Y = Op1
bool isSigned = I.getOpcode() == Instruction::SDiv;
if ((isSigned && match(Z, m_SRem(m_Specific(X), m_Specific(Op1)))) ||
(!isSigned && match(Z, m_URem(m_Specific(X), m_Specific(Op1)))))
return BinaryOperator::Create(I.getOpcode(), X, Op1);
}
return nullptr;
}
/// dyn_castZExtVal - Checks if V is a zext or constant that can
/// be truncated to Ty without losing bits.
static Value *dyn_castZExtVal(Value *V, Type *Ty) {
if (ZExtInst *Z = dyn_cast<ZExtInst>(V)) {
if (Z->getSrcTy() == Ty)
return Z->getOperand(0);
} else if (ConstantInt *C = dyn_cast<ConstantInt>(V)) {
if (C->getValue().getActiveBits() <= cast<IntegerType>(Ty)->getBitWidth())
return ConstantExpr::getTrunc(C, Ty);
}
return nullptr;
}
namespace {
const unsigned MaxDepth = 6;
typedef Instruction *(*FoldUDivOperandCb)(Value *Op0, Value *Op1,
const BinaryOperator &I,
InstCombiner &IC);
/// \brief Used to maintain state for visitUDivOperand().
struct UDivFoldAction {
FoldUDivOperandCb FoldAction; ///< Informs visitUDiv() how to fold this
///< operand. This can be zero if this action
///< joins two actions together.
Value *OperandToFold; ///< Which operand to fold.
union {
Instruction *FoldResult; ///< The instruction returned when FoldAction is
///< invoked.
size_t SelectLHSIdx; ///< Stores the LHS action index if this action
///< joins two actions together.
};
UDivFoldAction(FoldUDivOperandCb FA, Value *InputOperand)
: FoldAction(FA), OperandToFold(InputOperand), FoldResult(nullptr) {}
UDivFoldAction(FoldUDivOperandCb FA, Value *InputOperand, size_t SLHS)
: FoldAction(FA), OperandToFold(InputOperand), SelectLHSIdx(SLHS) {}
};
}
// X udiv 2^C -> X >> C
static Instruction *foldUDivPow2Cst(Value *Op0, Value *Op1,
const BinaryOperator &I, InstCombiner &IC) {
const APInt &C = cast<Constant>(Op1)->getUniqueInteger();
BinaryOperator *LShr = BinaryOperator::CreateLShr(
Op0, ConstantInt::get(Op0->getType(), C.logBase2()));
if (I.isExact())
LShr->setIsExact();
return LShr;
}
// X udiv C, where C >= signbit
static Instruction *foldUDivNegCst(Value *Op0, Value *Op1,
const BinaryOperator &I, InstCombiner &IC) {
Value *ICI = IC.Builder->CreateICmpULT(Op0, cast<ConstantInt>(Op1));
return SelectInst::Create(ICI, Constant::getNullValue(I.getType()),
ConstantInt::get(I.getType(), 1));
}
// X udiv (C1 << N), where C1 is "1<<C2" --> X >> (N+C2)
static Instruction *foldUDivShl(Value *Op0, Value *Op1, const BinaryOperator &I,
InstCombiner &IC) {
Instruction *ShiftLeft = cast<Instruction>(Op1);
if (isa<ZExtInst>(ShiftLeft))
ShiftLeft = cast<Instruction>(ShiftLeft->getOperand(0));
const APInt &CI =
cast<Constant>(ShiftLeft->getOperand(0))->getUniqueInteger();
Value *N = ShiftLeft->getOperand(1);
if (CI != 1)
N = IC.Builder->CreateAdd(N, ConstantInt::get(N->getType(), CI.logBase2()));
if (ZExtInst *Z = dyn_cast<ZExtInst>(Op1))
N = IC.Builder->CreateZExt(N, Z->getDestTy());
BinaryOperator *LShr = BinaryOperator::CreateLShr(Op0, N);
if (I.isExact())
LShr->setIsExact();
return LShr;
}
// \brief Recursively visits the possible right hand operands of a udiv
// instruction, seeing through select instructions, to determine if we can
// replace the udiv with something simpler. If we find that an operand is not
// able to simplify the udiv, we abort the entire transformation.
static size_t visitUDivOperand(Value *Op0, Value *Op1, const BinaryOperator &I,
SmallVectorImpl<UDivFoldAction> &Actions,
unsigned Depth = 0) {
// Check to see if this is an unsigned division with an exact power of 2,
// if so, convert to a right shift.
if (match(Op1, m_Power2())) {
Actions.push_back(UDivFoldAction(foldUDivPow2Cst, Op1));
return Actions.size();
}
if (ConstantInt *C = dyn_cast<ConstantInt>(Op1))
// X udiv C, where C >= signbit
if (C->getValue().isNegative()) {
Actions.push_back(UDivFoldAction(foldUDivNegCst, C));
return Actions.size();
}
// X udiv (C1 << N), where C1 is "1<<C2" --> X >> (N+C2)
if (match(Op1, m_Shl(m_Power2(), m_Value())) ||
match(Op1, m_ZExt(m_Shl(m_Power2(), m_Value())))) {
Actions.push_back(UDivFoldAction(foldUDivShl, Op1));
return Actions.size();
}
// The remaining tests are all recursive, so bail out if we hit the limit.
if (Depth++ == MaxDepth)
return 0;
if (SelectInst *SI = dyn_cast<SelectInst>(Op1))
if (size_t LHSIdx =
visitUDivOperand(Op0, SI->getOperand(1), I, Actions, Depth))
if (visitUDivOperand(Op0, SI->getOperand(2), I, Actions, Depth)) {
Actions.push_back(UDivFoldAction(nullptr, Op1, LHSIdx - 1));
return Actions.size();
}
return 0;
}
Instruction *InstCombiner::visitUDiv(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifyUDivInst(Op0, Op1, DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
// Handle the integer div common cases
if (Instruction *Common = commonIDivTransforms(I))
return Common;
// (x lshr C1) udiv C2 --> x udiv (C2 << C1)
{
Value *X;
const APInt *C1, *C2;
if (match(Op0, m_LShr(m_Value(X), m_APInt(C1))) &&
match(Op1, m_APInt(C2))) {
bool Overflow;
APInt C2ShlC1 = C2->ushl_ov(*C1, Overflow);
if (!Overflow) {
bool IsExact = I.isExact() && match(Op0, m_Exact(m_Value()));
BinaryOperator *BO = BinaryOperator::CreateUDiv(
X, ConstantInt::get(X->getType(), C2ShlC1));
if (IsExact)
BO->setIsExact();
return BO;
}
}
}
// (zext A) udiv (zext B) --> zext (A udiv B)
if (ZExtInst *ZOp0 = dyn_cast<ZExtInst>(Op0))
if (Value *ZOp1 = dyn_castZExtVal(Op1, ZOp0->getSrcTy()))
return new ZExtInst(
Builder->CreateUDiv(ZOp0->getOperand(0), ZOp1, "div", I.isExact()),
I.getType());
// (LHS udiv (select (select (...)))) -> (LHS >> (select (select (...))))
SmallVector<UDivFoldAction, 6> UDivActions;
if (visitUDivOperand(Op0, Op1, I, UDivActions))
for (unsigned i = 0, e = UDivActions.size(); i != e; ++i) {
FoldUDivOperandCb Action = UDivActions[i].FoldAction;
Value *ActionOp1 = UDivActions[i].OperandToFold;
Instruction *Inst;
if (Action)
Inst = Action(Op0, ActionOp1, I, *this);
else {
// This action joins two actions together. The RHS of this action is
// simply the last action we processed, we saved the LHS action index in
// the joining action.
size_t SelectRHSIdx = i - 1;
Value *SelectRHS = UDivActions[SelectRHSIdx].FoldResult;
size_t SelectLHSIdx = UDivActions[i].SelectLHSIdx;
Value *SelectLHS = UDivActions[SelectLHSIdx].FoldResult;
Inst = SelectInst::Create(cast<SelectInst>(ActionOp1)->getCondition(),
SelectLHS, SelectRHS);
}
// If this is the last action to process, return it to the InstCombiner.
// Otherwise, we insert it before the UDiv and record it so that we may
// use it as part of a joining action (i.e., a SelectInst).
if (e - i != 1) {
Inst->insertBefore(&I);
UDivActions[i].FoldResult = Inst;
} else
return Inst;
}
return nullptr;
}
Instruction *InstCombiner::visitSDiv(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifySDivInst(Op0, Op1, DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
// Handle the integer div common cases
if (Instruction *Common = commonIDivTransforms(I))
return Common;
// sdiv X, -1 == -X
if (match(Op1, m_AllOnes()))
return BinaryOperator::CreateNeg(Op0);
if (ConstantInt *RHS = dyn_cast<ConstantInt>(Op1)) {
// sdiv X, C --> ashr exact X, log2(C)
if (I.isExact() && RHS->getValue().isNonNegative() &&
RHS->getValue().isPowerOf2()) {
Value *ShAmt = llvm::ConstantInt::get(RHS->getType(),
RHS->getValue().exactLogBase2());
return BinaryOperator::CreateExactAShr(Op0, ShAmt, I.getName());
}
}
if (Constant *RHS = dyn_cast<Constant>(Op1)) {
// X/INT_MIN -> X == INT_MIN
if (RHS->isMinSignedValue())
return new ZExtInst(Builder->CreateICmpEQ(Op0, Op1), I.getType());
// -X/C --> X/-C provided the negation doesn't overflow.
Value *X;
if (match(Op0, m_NSWSub(m_Zero(), m_Value(X)))) {
auto *BO = BinaryOperator::CreateSDiv(X, ConstantExpr::getNeg(RHS));
BO->setIsExact(I.isExact());
return BO;
}
}
// If the sign bits of both operands are zero (i.e. we can prove they are
// unsigned inputs), turn this into a udiv.
if (I.getType()->isIntegerTy()) {
APInt Mask(APInt::getSignBit(I.getType()->getPrimitiveSizeInBits()));
if (MaskedValueIsZero(Op0, Mask, 0, &I)) {
if (MaskedValueIsZero(Op1, Mask, 0, &I)) {
// X sdiv Y -> X udiv Y, iff X and Y don't have sign bit set
auto *BO = BinaryOperator::CreateUDiv(Op0, Op1, I.getName());
BO->setIsExact(I.isExact());
return BO;
}
if (isKnownToBeAPowerOfTwo(Op1, DL, /*OrZero*/ true, 0, AC, &I, DT)) {
// X sdiv (1 << Y) -> X udiv (1 << Y) ( -> X u>> Y)
// Safe because the only negative value (1 << Y) can take on is
// INT_MIN, and X sdiv INT_MIN == X udiv INT_MIN == 0 if X doesn't have
// the sign bit set.
auto *BO = BinaryOperator::CreateUDiv(Op0, Op1, I.getName());
BO->setIsExact(I.isExact());
return BO;
}
}
}
return nullptr;
}
/// CvtFDivConstToReciprocal tries to convert X/C into X*1/C if C not a special
/// FP value and:
/// 1) 1/C is exact, or
/// 2) reciprocal is allowed.
/// If the conversion was successful, the simplified expression "X * 1/C" is
/// returned; otherwise, NULL is returned.
///
static Instruction *CvtFDivConstToReciprocal(Value *Dividend, Constant *Divisor,
bool AllowReciprocal) {
if (!isa<ConstantFP>(Divisor)) // TODO: handle vectors.
return nullptr;
const APFloat &FpVal = cast<ConstantFP>(Divisor)->getValueAPF();
APFloat Reciprocal(FpVal.getSemantics());
bool Cvt = FpVal.getExactInverse(&Reciprocal);
if (!Cvt && AllowReciprocal && FpVal.isFiniteNonZero()) {
Reciprocal = APFloat(FpVal.getSemantics(), 1.0f);
(void)Reciprocal.divide(FpVal, APFloat::rmNearestTiesToEven);
Cvt = !Reciprocal.isDenormal();
}
if (!Cvt)
return nullptr;
ConstantFP *R;
R = ConstantFP::get(Dividend->getType()->getContext(), Reciprocal);
return BinaryOperator::CreateFMul(Dividend, R);
}
Instruction *InstCombiner::visitFDiv(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifyFDivInst(Op0, Op1, I.getFastMathFlags(),
DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
if (isa<Constant>(Op0))
if (SelectInst *SI = dyn_cast<SelectInst>(Op1))
if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
bool AllowReassociate = I.hasUnsafeAlgebra();
bool AllowReciprocal = I.hasAllowReciprocal();
if (Constant *Op1C = dyn_cast<Constant>(Op1)) {
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (AllowReassociate) {
Constant *C1 = nullptr;
Constant *C2 = Op1C;
Value *X;
Instruction *Res = nullptr;
if (match(Op0, m_FMul(m_Value(X), m_Constant(C1)))) {
// (X*C1)/C2 => X * (C1/C2)
//
Constant *C = ConstantExpr::getFDiv(C1, C2);
if (isNormalFp(C))
Res = BinaryOperator::CreateFMul(X, C);
} else if (match(Op0, m_FDiv(m_Value(X), m_Constant(C1)))) {
// (X/C1)/C2 => X /(C2*C1) [=> X * 1/(C2*C1) if reciprocal is allowed]
//
Constant *C = ConstantExpr::getFMul(C1, C2);
if (isNormalFp(C)) {
Res = CvtFDivConstToReciprocal(X, C, AllowReciprocal);
if (!Res)
Res = BinaryOperator::CreateFDiv(X, C);
}
}
if (Res) {
Res->setFastMathFlags(I.getFastMathFlags());
return Res;
}
}
// X / C => X * 1/C
if (Instruction *T = CvtFDivConstToReciprocal(Op0, Op1C, AllowReciprocal)) {
T->copyFastMathFlags(&I);
return T;
}
return nullptr;
}
if (AllowReassociate && isa<Constant>(Op0)) {
Constant *C1 = cast<Constant>(Op0), *C2;
Constant *Fold = nullptr;
Value *X;
bool CreateDiv = true;
// C1 / (X*C2) => (C1/C2) / X
if (match(Op1, m_FMul(m_Value(X), m_Constant(C2))))
Fold = ConstantExpr::getFDiv(C1, C2);
else if (match(Op1, m_FDiv(m_Value(X), m_Constant(C2)))) {
// C1 / (X/C2) => (C1*C2) / X
Fold = ConstantExpr::getFMul(C1, C2);
} else if (match(Op1, m_FDiv(m_Constant(C2), m_Value(X)))) {
// C1 / (C2/X) => (C1/C2) * X
Fold = ConstantExpr::getFDiv(C1, C2);
CreateDiv = false;
}
if (Fold && isNormalFp(Fold)) {
Instruction *R = CreateDiv ? BinaryOperator::CreateFDiv(Fold, X)
: BinaryOperator::CreateFMul(X, Fold);
R->setFastMathFlags(I.getFastMathFlags());
return R;
}
return nullptr;
}
if (AllowReassociate) {
Value *X, *Y;
Value *NewInst = nullptr;
Instruction *SimpR = nullptr;
if (Op0->hasOneUse() && match(Op0, m_FDiv(m_Value(X), m_Value(Y)))) {
// (X/Y) / Z => X / (Y*Z)
//
if (!isa<Constant>(Y) || !isa<Constant>(Op1)) {
NewInst = Builder->CreateFMul(Y, Op1);
if (Instruction *RI = dyn_cast<Instruction>(NewInst)) {
FastMathFlags Flags = I.getFastMathFlags();
Flags &= cast<Instruction>(Op0)->getFastMathFlags();
RI->setFastMathFlags(Flags);
}
SimpR = BinaryOperator::CreateFDiv(X, NewInst);
}
} else if (Op1->hasOneUse() && match(Op1, m_FDiv(m_Value(X), m_Value(Y)))) {
// Z / (X/Y) => Z*Y / X
//
if (!isa<Constant>(Y) || !isa<Constant>(Op0)) {
NewInst = Builder->CreateFMul(Op0, Y);
if (Instruction *RI = dyn_cast<Instruction>(NewInst)) {
FastMathFlags Flags = I.getFastMathFlags();
Flags &= cast<Instruction>(Op1)->getFastMathFlags();
RI->setFastMathFlags(Flags);
}
SimpR = BinaryOperator::CreateFDiv(NewInst, X);
}
}
if (NewInst) {
if (Instruction *T = dyn_cast<Instruction>(NewInst))
T->setDebugLoc(I.getDebugLoc());
SimpR->setFastMathFlags(I.getFastMathFlags());
return SimpR;
}
}
return nullptr;
}
/// This function implements the transforms common to both integer remainder
/// instructions (urem and srem). It is called by the visitors to those integer
/// remainder instructions.
/// @brief Common integer remainder transforms
Instruction *InstCombiner::commonIRemTransforms(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
// The RHS is known non-zero.
if (Value *V = simplifyValueKnownNonZero(I.getOperand(1), *this, I)) {
I.setOperand(1, V);
return &I;
}
// Handle cases involving: rem X, (select Cond, Y, Z)
if (isa<SelectInst>(Op1) && SimplifyDivRemOfSelect(I))
return &I;
if (isa<Constant>(Op1)) {
if (Instruction *Op0I = dyn_cast<Instruction>(Op0)) {
if (SelectInst *SI = dyn_cast<SelectInst>(Op0I)) {
if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
} else if (isa<PHINode>(Op0I)) {
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
}
// See if we can fold away this rem instruction.
if (SimplifyDemandedInstructionBits(I))
return &I;
}
}
return nullptr;
}
Instruction *InstCombiner::visitURem(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifyURemInst(Op0, Op1, DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
if (Instruction *common = commonIRemTransforms(I))
return common;
// (zext A) urem (zext B) --> zext (A urem B)
if (ZExtInst *ZOp0 = dyn_cast<ZExtInst>(Op0))
if (Value *ZOp1 = dyn_castZExtVal(Op1, ZOp0->getSrcTy()))
return new ZExtInst(Builder->CreateURem(ZOp0->getOperand(0), ZOp1),
I.getType());
// X urem Y -> X and Y-1, where Y is a power of 2,
if (isKnownToBeAPowerOfTwo(Op1, DL, /*OrZero*/ true, 0, AC, &I, DT)) {
Constant *N1 = Constant::getAllOnesValue(I.getType());
Value *Add = Builder->CreateAdd(Op1, N1);
return BinaryOperator::CreateAnd(Op0, Add);
}
// 1 urem X -> zext(X != 1)
if (match(Op0, m_One())) {
Value *Cmp = Builder->CreateICmpNE(Op1, Op0);
Value *Ext = Builder->CreateZExt(Cmp, I.getType());
return ReplaceInstUsesWith(I, Ext);
}
return nullptr;
}
Instruction *InstCombiner::visitSRem(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifySRemInst(Op0, Op1, DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
// Handle the integer rem common cases
if (Instruction *Common = commonIRemTransforms(I))
return Common;
{
const APInt *Y;
// X % -Y -> X % Y
if (match(Op1, m_APInt(Y)) && Y->isNegative() && !Y->isMinSignedValue()) {
Worklist.AddValue(I.getOperand(1));
I.setOperand(1, ConstantInt::get(I.getType(), -*Y));
return &I;
}
}
// If the sign bits of both operands are zero (i.e. we can prove they are
// unsigned inputs), turn this into a urem.
if (I.getType()->isIntegerTy()) {
APInt Mask(APInt::getSignBit(I.getType()->getPrimitiveSizeInBits()));
if (MaskedValueIsZero(Op1, Mask, 0, &I) &&
MaskedValueIsZero(Op0, Mask, 0, &I)) {
// X srem Y -> X urem Y, iff X and Y don't have sign bit set
return BinaryOperator::CreateURem(Op0, Op1, I.getName());
}
}
// If it's a constant vector, flip any negative values positive.
if (isa<ConstantVector>(Op1) || isa<ConstantDataVector>(Op1)) {
Constant *C = cast<Constant>(Op1);
unsigned VWidth = C->getType()->getVectorNumElements();
bool hasNegative = false;
bool hasMissing = false;
for (unsigned i = 0; i != VWidth; ++i) {
Constant *Elt = C->getAggregateElement(i);
if (!Elt) {
hasMissing = true;
break;
}
if (ConstantInt *RHS = dyn_cast<ConstantInt>(Elt))
if (RHS->isNegative())
hasNegative = true;
}
if (hasNegative && !hasMissing) {
SmallVector<Constant *, 16> Elts(VWidth);
for (unsigned i = 0; i != VWidth; ++i) {
Elts[i] = C->getAggregateElement(i); // Handle undef, etc.
if (ConstantInt *RHS = dyn_cast<ConstantInt>(Elts[i])) {
if (RHS->isNegative())
Elts[i] = cast<ConstantInt>(ConstantExpr::getNeg(RHS));
}
}
Constant *NewRHSV = ConstantVector::get(Elts);
if (NewRHSV != C) { // Don't loop on -MININT
Worklist.AddValue(I.getOperand(1));
I.setOperand(1, NewRHSV);
return &I;
}
}
}
return nullptr;
}
Instruction *InstCombiner::visitFRem(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifyFRemInst(Op0, Op1, I.getFastMathFlags(),
DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
// Handle cases involving: rem X, (select Cond, Y, Z)
if (isa<SelectInst>(Op1) && SimplifyDivRemOfSelect(I))
return &I;
return nullptr;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp | //===- InstCombineLoadStoreAlloca.cpp -------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the visit functions for load, store and alloca.
//
//===----------------------------------------------------------------------===//
#include "InstCombineInternal.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/Loads.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include "dxc/DXIL/DxilOperations.h" // HLSL Change - avoid unpack for dxil types.
using namespace llvm;
#define DEBUG_TYPE "instcombine"
STATISTIC(NumDeadStore, "Number of dead stores eliminated");
STATISTIC(NumGlobalCopies, "Number of allocas copied from constant global");
/// pointsToConstantGlobal - Return true if V (possibly indirectly) points to
/// some part of a constant global variable. This intentionally only accepts
/// constant expressions because we can't rewrite arbitrary instructions.
static bool pointsToConstantGlobal(Value *V) {
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V))
return GV->isConstant();
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
if (CE->getOpcode() == Instruction::BitCast ||
CE->getOpcode() == Instruction::AddrSpaceCast ||
CE->getOpcode() == Instruction::GetElementPtr)
return pointsToConstantGlobal(CE->getOperand(0));
}
return false;
}
/// isOnlyCopiedFromConstantGlobal - Recursively walk the uses of a (derived)
/// pointer to an alloca. Ignore any reads of the pointer, return false if we
/// see any stores or other unknown uses. If we see pointer arithmetic, keep
/// track of whether it moves the pointer (with IsOffset) but otherwise traverse
/// the uses. If we see a memcpy/memmove that targets an unoffseted pointer to
/// the alloca, and if the source pointer is a pointer to a constant global, we
/// can optimize this.
static bool
isOnlyCopiedFromConstantGlobal(Value *V, MemTransferInst *&TheCopy,
SmallVectorImpl<Instruction *> &ToDelete) {
// We track lifetime intrinsics as we encounter them. If we decide to go
// ahead and replace the value with the global, this lets the caller quickly
// eliminate the markers.
SmallVector<std::pair<Value *, bool>, 35> ValuesToInspect;
ValuesToInspect.push_back(std::make_pair(V, false));
while (!ValuesToInspect.empty()) {
auto ValuePair = ValuesToInspect.pop_back_val();
const bool IsOffset = ValuePair.second;
for (auto &U : ValuePair.first->uses()) {
Instruction *I = cast<Instruction>(U.getUser());
if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
// Ignore non-volatile loads, they are always ok.
if (!LI->isSimple()) return false;
continue;
}
if (isa<BitCastInst>(I) || isa<AddrSpaceCastInst>(I)) {
// If uses of the bitcast are ok, we are ok.
ValuesToInspect.push_back(std::make_pair(I, IsOffset));
continue;
}
if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(I)) {
// If the GEP has all zero indices, it doesn't offset the pointer. If it
// doesn't, it does.
ValuesToInspect.push_back(
std::make_pair(I, IsOffset || !GEP->hasAllZeroIndices()));
continue;
}
if (auto CS = CallSite(I)) {
// If this is the function being called then we treat it like a load and
// ignore it.
if (CS.isCallee(&U))
continue;
// Inalloca arguments are clobbered by the call.
unsigned ArgNo = CS.getArgumentNo(&U);
if (CS.isInAllocaArgument(ArgNo))
return false;
// If this is a readonly/readnone call site, then we know it is just a
// load (but one that potentially returns the value itself), so we can
// ignore it if we know that the value isn't captured.
if (CS.onlyReadsMemory() &&
(CS.getInstruction()->use_empty() || CS.doesNotCapture(ArgNo)))
continue;
// If this is being passed as a byval argument, the caller is making a
// copy, so it is only a read of the alloca.
if (CS.isByValArgument(ArgNo))
continue;
}
// Lifetime intrinsics can be handled by the caller.
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I)) {
if (II->getIntrinsicID() == Intrinsic::lifetime_start ||
II->getIntrinsicID() == Intrinsic::lifetime_end) {
assert(II->use_empty() && "Lifetime markers have no result to use!");
ToDelete.push_back(II);
continue;
}
}
// If this is isn't our memcpy/memmove, reject it as something we can't
// handle.
MemTransferInst *MI = dyn_cast<MemTransferInst>(I);
if (!MI)
return false;
// If the transfer is using the alloca as a source of the transfer, then
// ignore it since it is a load (unless the transfer is volatile).
if (U.getOperandNo() == 1) {
if (MI->isVolatile()) return false;
continue;
}
// If we already have seen a copy, reject the second one.
if (TheCopy) return false;
// If the pointer has been offset from the start of the alloca, we can't
// safely handle this.
if (IsOffset) return false;
// If the memintrinsic isn't using the alloca as the dest, reject it.
if (U.getOperandNo() != 0) return false;
// If the source of the memcpy/move is not a constant global, reject it.
if (!pointsToConstantGlobal(MI->getSource()))
return false;
// Otherwise, the transform is safe. Remember the copy instruction.
TheCopy = MI;
}
}
return true;
}
/// isOnlyCopiedFromConstantGlobal - Return true if the specified alloca is only
/// modified by a copy from a constant global. If we can prove this, we can
/// replace any uses of the alloca with uses of the global directly.
static MemTransferInst *
isOnlyCopiedFromConstantGlobal(AllocaInst *AI,
SmallVectorImpl<Instruction *> &ToDelete) {
MemTransferInst *TheCopy = nullptr;
if (isOnlyCopiedFromConstantGlobal(AI, TheCopy, ToDelete))
return TheCopy;
return nullptr;
}
static Instruction *simplifyAllocaArraySize(InstCombiner &IC, AllocaInst &AI) {
// Check for array size of 1 (scalar allocation).
if (!AI.isArrayAllocation()) {
// i32 1 is the canonical array size for scalar allocations.
if (AI.getArraySize()->getType()->isIntegerTy(32))
return nullptr;
// Canonicalize it.
Value *V = IC.Builder->getInt32(1);
AI.setOperand(0, V);
return &AI;
}
// Convert: alloca Ty, C - where C is a constant != 1 into: alloca [C x Ty], 1
if (const ConstantInt *C = dyn_cast<ConstantInt>(AI.getArraySize())) {
Type *NewTy = ArrayType::get(AI.getAllocatedType(), C->getZExtValue());
AllocaInst *New = IC.Builder->CreateAlloca(NewTy, nullptr, AI.getName());
New->setAlignment(AI.getAlignment());
// Scan to the end of the allocation instructions, to skip over a block of
// allocas if possible...also skip interleaved debug info
//
BasicBlock::iterator It = New;
while (isa<AllocaInst>(*It) || isa<DbgInfoIntrinsic>(*It))
++It;
// Now that I is pointing to the first non-allocation-inst in the block,
// insert our getelementptr instruction...
//
Type *IdxTy = IC.getDataLayout().getIntPtrType(AI.getType());
Value *NullIdx = Constant::getNullValue(IdxTy);
Value *Idx[2] = {NullIdx, NullIdx};
Instruction *GEP =
GetElementPtrInst::CreateInBounds(New, Idx, New->getName() + ".sub");
IC.InsertNewInstBefore(GEP, *It);
// Now make everything use the getelementptr instead of the original
// allocation.
return IC.ReplaceInstUsesWith(AI, GEP);
}
if (isa<UndefValue>(AI.getArraySize()))
return IC.ReplaceInstUsesWith(AI, Constant::getNullValue(AI.getType()));
// Ensure that the alloca array size argument has type intptr_t, so that
// any casting is exposed early.
Type *IntPtrTy = IC.getDataLayout().getIntPtrType(AI.getType());
if (AI.getArraySize()->getType() != IntPtrTy) {
Value *V = IC.Builder->CreateIntCast(AI.getArraySize(), IntPtrTy, false);
AI.setOperand(0, V);
return &AI;
}
return nullptr;
}
Instruction *InstCombiner::visitAllocaInst(AllocaInst &AI) {
if (auto *I = simplifyAllocaArraySize(*this, AI))
return I;
if (AI.getAllocatedType()->isSized()) {
// If the alignment is 0 (unspecified), assign it the preferred alignment.
if (AI.getAlignment() == 0)
AI.setAlignment(DL.getPrefTypeAlignment(AI.getAllocatedType()));
// Move all alloca's of zero byte objects to the entry block and merge them
// together. Note that we only do this for alloca's, because malloc should
// allocate and return a unique pointer, even for a zero byte allocation.
if (DL.getTypeAllocSize(AI.getAllocatedType()) == 0) {
// For a zero sized alloca there is no point in doing an array allocation.
// This is helpful if the array size is a complicated expression not used
// elsewhere.
if (AI.isArrayAllocation()) {
AI.setOperand(0, ConstantInt::get(AI.getArraySize()->getType(), 1));
return &AI;
}
// Get the first instruction in the entry block.
BasicBlock &EntryBlock = AI.getParent()->getParent()->getEntryBlock();
Instruction *FirstInst = EntryBlock.getFirstNonPHIOrDbg();
if (FirstInst != &AI) {
// If the entry block doesn't start with a zero-size alloca then move
// this one to the start of the entry block. There is no problem with
// dominance as the array size was forced to a constant earlier already.
AllocaInst *EntryAI = dyn_cast<AllocaInst>(FirstInst);
if (!EntryAI || !EntryAI->getAllocatedType()->isSized() ||
DL.getTypeAllocSize(EntryAI->getAllocatedType()) != 0) {
AI.moveBefore(FirstInst);
return &AI;
}
// If the alignment of the entry block alloca is 0 (unspecified),
// assign it the preferred alignment.
if (EntryAI->getAlignment() == 0)
EntryAI->setAlignment(
DL.getPrefTypeAlignment(EntryAI->getAllocatedType()));
// Replace this zero-sized alloca with the one at the start of the entry
// block after ensuring that the address will be aligned enough for both
// types.
unsigned MaxAlign = std::max(EntryAI->getAlignment(),
AI.getAlignment());
EntryAI->setAlignment(MaxAlign);
if (AI.getType() != EntryAI->getType())
return new BitCastInst(EntryAI, AI.getType());
return ReplaceInstUsesWith(AI, EntryAI);
}
}
}
if (AI.getAlignment()) {
// Check to see if this allocation is only modified by a memcpy/memmove from
// a constant global whose alignment is equal to or exceeds that of the
// allocation. If this is the case, we can change all users to use
// the constant global instead. This is commonly produced by the CFE by
// constructs like "void foo() { int A[] = {1,2,3,4,5,6,7,8,9...}; }" if 'A'
// is only subsequently read.
SmallVector<Instruction *, 4> ToDelete;
if (MemTransferInst *Copy = isOnlyCopiedFromConstantGlobal(&AI, ToDelete)) {
unsigned SourceAlign = getOrEnforceKnownAlignment(
Copy->getSource(), AI.getAlignment(), DL, &AI, AC, DT);
if (AI.getAlignment() <= SourceAlign) {
DEBUG(dbgs() << "Found alloca equal to global: " << AI << '\n');
DEBUG(dbgs() << " memcpy = " << *Copy << '\n');
for (unsigned i = 0, e = ToDelete.size(); i != e; ++i)
EraseInstFromFunction(*ToDelete[i]);
Constant *TheSrc = cast<Constant>(Copy->getSource());
Constant *Cast
= ConstantExpr::getPointerBitCastOrAddrSpaceCast(TheSrc, AI.getType());
Instruction *NewI = ReplaceInstUsesWith(AI, Cast);
EraseInstFromFunction(*Copy);
++NumGlobalCopies;
return NewI;
}
}
}
// At last, use the generic allocation site handler to aggressively remove
// unused allocas.
return visitAllocSite(AI);
}
/// \brief Helper to combine a load to a new type.
///
/// This just does the work of combining a load to a new type. It handles
/// metadata, etc., and returns the new instruction. The \c NewTy should be the
/// loaded *value* type. This will convert it to a pointer, cast the operand to
/// that pointer type, load it, etc.
///
/// Note that this will create all of the instructions with whatever insert
/// point the \c InstCombiner currently is using.
static LoadInst *combineLoadToNewType(InstCombiner &IC, LoadInst &LI, Type *NewTy,
const Twine &Suffix = "") {
Value *Ptr = LI.getPointerOperand();
unsigned AS = LI.getPointerAddressSpace();
SmallVector<std::pair<unsigned, MDNode *>, 8> MD;
LI.getAllMetadata(MD);
LoadInst *NewLoad = IC.Builder->CreateAlignedLoad(
IC.Builder->CreateBitCast(Ptr, NewTy->getPointerTo(AS)),
LI.getAlignment(), LI.getName() + Suffix);
MDBuilder MDB(NewLoad->getContext());
for (const auto &MDPair : MD) {
unsigned ID = MDPair.first;
MDNode *N = MDPair.second;
// Note, essentially every kind of metadata should be preserved here! This
// routine is supposed to clone a load instruction changing *only its type*.
// The only metadata it makes sense to drop is metadata which is invalidated
// when the pointer type changes. This should essentially never be the case
// in LLVM, but we explicitly switch over only known metadata to be
// conservatively correct. If you are adding metadata to LLVM which pertains
// to loads, you almost certainly want to add it here.
switch (ID) {
case LLVMContext::MD_dbg:
case LLVMContext::MD_tbaa:
case LLVMContext::MD_prof:
case LLVMContext::MD_fpmath:
case LLVMContext::MD_tbaa_struct:
case LLVMContext::MD_invariant_load:
case LLVMContext::MD_alias_scope:
case LLVMContext::MD_noalias:
case LLVMContext::MD_nontemporal:
case LLVMContext::MD_mem_parallel_loop_access:
// All of these directly apply.
NewLoad->setMetadata(ID, N);
break;
case LLVMContext::MD_nonnull:
// This only directly applies if the new type is also a pointer.
if (NewTy->isPointerTy()) {
NewLoad->setMetadata(ID, N);
break;
}
// If it's integral now, translate it to !range metadata.
if (NewTy->isIntegerTy()) {
auto *ITy = cast<IntegerType>(NewTy);
auto *NullInt = ConstantExpr::getPtrToInt(
ConstantPointerNull::get(cast<PointerType>(Ptr->getType())), ITy);
auto *NonNullInt =
ConstantExpr::getAdd(NullInt, ConstantInt::get(ITy, 1));
NewLoad->setMetadata(LLVMContext::MD_range,
MDB.createRange(NonNullInt, NullInt));
}
break;
case LLVMContext::MD_range:
// FIXME: It would be nice to propagate this in some way, but the type
// conversions make it hard. If the new type is a pointer, we could
// translate it to !nonnull metadata.
break;
}
}
return NewLoad;
}
/// \brief Combine a store to a new type.
///
/// Returns the newly created store instruction.
static StoreInst *combineStoreToNewValue(InstCombiner &IC, StoreInst &SI, Value *V) {
Value *Ptr = SI.getPointerOperand();
unsigned AS = SI.getPointerAddressSpace();
SmallVector<std::pair<unsigned, MDNode *>, 8> MD;
SI.getAllMetadata(MD);
StoreInst *NewStore = IC.Builder->CreateAlignedStore(
V, IC.Builder->CreateBitCast(Ptr, V->getType()->getPointerTo(AS)),
SI.getAlignment());
for (const auto &MDPair : MD) {
unsigned ID = MDPair.first;
MDNode *N = MDPair.second;
// Note, essentially every kind of metadata should be preserved here! This
// routine is supposed to clone a store instruction changing *only its
// type*. The only metadata it makes sense to drop is metadata which is
// invalidated when the pointer type changes. This should essentially
// never be the case in LLVM, but we explicitly switch over only known
// metadata to be conservatively correct. If you are adding metadata to
// LLVM which pertains to stores, you almost certainly want to add it
// here.
switch (ID) {
case LLVMContext::MD_dbg:
case LLVMContext::MD_tbaa:
case LLVMContext::MD_prof:
case LLVMContext::MD_fpmath:
case LLVMContext::MD_tbaa_struct:
case LLVMContext::MD_alias_scope:
case LLVMContext::MD_noalias:
case LLVMContext::MD_nontemporal:
case LLVMContext::MD_mem_parallel_loop_access:
// All of these directly apply.
NewStore->setMetadata(ID, N);
break;
case LLVMContext::MD_invariant_load:
case LLVMContext::MD_nonnull:
case LLVMContext::MD_range:
// These don't apply for stores.
break;
}
}
return NewStore;
}
/// \brief Combine loads to match the type of value their uses after looking
/// through intervening bitcasts.
///
/// The core idea here is that if the result of a load is used in an operation,
/// we should load the type most conducive to that operation. For example, when
/// loading an integer and converting that immediately to a pointer, we should
/// instead directly load a pointer.
///
/// However, this routine must never change the width of a load or the number of
/// loads as that would introduce a semantic change. This combine is expected to
/// be a semantic no-op which just allows loads to more closely model the types
/// of their consuming operations.
///
/// Currently, we also refuse to change the precise type used for an atomic load
/// or a volatile load. This is debatable, and might be reasonable to change
/// later. However, it is risky in case some backend or other part of LLVM is
/// relying on the exact type loaded to select appropriate atomic operations.
static Instruction *combineLoadToOperationType(InstCombiner &IC, LoadInst &LI) {
#if 0 // HLSL Change - bitcast to i32* won't help HLSL.
// FIXME: We could probably with some care handle both volatile and atomic
// loads here but it isn't clear that this is important.
if (!LI.isSimple())
return nullptr;
if (LI.use_empty())
return nullptr;
Type *Ty = LI.getType();
const DataLayout &DL = IC.getDataLayout();
// Try to canonicalize loads which are only ever stored to operate over
// integers instead of any other type. We only do this when the loaded type
// is sized and has a size exactly the same as its store size and the store
// size is a legal integer type.
if (!Ty->isIntegerTy() && Ty->isSized() &&
DL.isLegalInteger(DL.getTypeStoreSizeInBits(Ty)) &&
DL.getTypeStoreSizeInBits(Ty) == DL.getTypeSizeInBits(Ty)) {
if (std::all_of(LI.user_begin(), LI.user_end(), [&LI](User *U) {
auto *SI = dyn_cast<StoreInst>(U);
return SI && SI->getPointerOperand() != &LI;
})) {
LoadInst *NewLoad = combineLoadToNewType(
IC, LI,
Type::getIntNTy(LI.getContext(), DL.getTypeStoreSizeInBits(Ty)));
// Replace all the stores with stores of the newly loaded value.
for (auto UI = LI.user_begin(), UE = LI.user_end(); UI != UE;) {
auto *SI = cast<StoreInst>(*UI++);
IC.Builder->SetInsertPoint(SI);
combineStoreToNewValue(IC, *SI, NewLoad);
IC.EraseInstFromFunction(*SI);
}
assert(LI.use_empty() && "Failed to remove all users of the load!");
// Return the old load so the combiner can delete it safely.
return &LI;
}
}
// Fold away bit casts of the loaded value by loading the desired type.
// We can do this for BitCastInsts as well as casts from and to pointer types,
// as long as those are noops (i.e., the source or dest type have the same
// bitwidth as the target's pointers).
if (LI.hasOneUse())
if (auto* CI = dyn_cast<CastInst>(LI.user_back())) {
if (CI->isNoopCast(DL)) {
LoadInst *NewLoad = combineLoadToNewType(IC, LI, CI->getDestTy());
CI->replaceAllUsesWith(NewLoad);
IC.EraseInstFromFunction(*CI);
return &LI;
}
}
// FIXME: We should also canonicalize loads of vectors when their elements are
// cast to other types.
return nullptr;
#else
return nullptr;
#endif // HLSL Change - bitcast to i32* won't help HLSL.
}
static Instruction *unpackLoadToAggregate(InstCombiner &IC, LoadInst &LI) {
// FIXME: We could probably with some care handle both volatile and atomic
// stores here but it isn't clear that this is important.
if (!LI.isSimple())
return nullptr;
Type *T = LI.getType();
if (!T->isAggregateType())
return nullptr;
assert(LI.getAlignment() && "Alignement must be set at this point");
if (auto *ST = dyn_cast<StructType>(T)) {
// If the struct only have one element, we unpack.
if (ST->getNumElements() == 1
&& false // HLSL Change - avoid unpack dxil types.
) {
LoadInst *NewLoad = combineLoadToNewType(IC, LI, ST->getTypeAtIndex(0U),
".unpack");
return IC.ReplaceInstUsesWith(LI, IC.Builder->CreateInsertValue(
UndefValue::get(T), NewLoad, 0, LI.getName()));
}
}
if (auto *AT = dyn_cast<ArrayType>(T)) {
// If the array only have one element, we unpack.
if (AT->getNumElements() == 1) {
LoadInst *NewLoad = combineLoadToNewType(IC, LI, AT->getElementType(),
".unpack");
return IC.ReplaceInstUsesWith(LI, IC.Builder->CreateInsertValue(
UndefValue::get(T), NewLoad, 0, LI.getName()));
}
}
return nullptr;
}
// If we can determine that all possible objects pointed to by the provided
// pointer value are, not only dereferenceable, but also definitively less than
// or equal to the provided maximum size, then return true. Otherwise, return
// false (constant global values and allocas fall into this category).
//
// FIXME: This should probably live in ValueTracking (or similar).
static bool isObjectSizeLessThanOrEq(Value *V, uint64_t MaxSize,
const DataLayout &DL) {
SmallPtrSet<Value *, 4> Visited;
SmallVector<Value *, 4> Worklist(1, V);
do {
Value *P = Worklist.pop_back_val();
P = P->stripPointerCasts();
if (!Visited.insert(P).second)
continue;
if (SelectInst *SI = dyn_cast<SelectInst>(P)) {
Worklist.push_back(SI->getTrueValue());
Worklist.push_back(SI->getFalseValue());
continue;
}
if (PHINode *PN = dyn_cast<PHINode>(P)) {
for (Value *IncValue : PN->incoming_values())
Worklist.push_back(IncValue);
continue;
}
if (GlobalAlias *GA = dyn_cast<GlobalAlias>(P)) {
if (GA->mayBeOverridden())
return false;
Worklist.push_back(GA->getAliasee());
continue;
}
// If we know how big this object is, and it is less than MaxSize, continue
// searching. Otherwise, return false.
if (AllocaInst *AI = dyn_cast<AllocaInst>(P)) {
if (!AI->getAllocatedType()->isSized())
return false;
ConstantInt *CS = dyn_cast<ConstantInt>(AI->getArraySize());
if (!CS)
return false;
uint64_t TypeSize = DL.getTypeAllocSize(AI->getAllocatedType());
// Make sure that, even if the multiplication below would wrap as an
// uint64_t, we still do the right thing.
if ((CS->getValue().zextOrSelf(128)*APInt(128, TypeSize)).ugt(MaxSize))
return false;
continue;
}
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(P)) {
if (!GV->hasDefinitiveInitializer() || !GV->isConstant())
return false;
uint64_t InitSize = DL.getTypeAllocSize(GV->getType()->getElementType());
if (InitSize > MaxSize)
return false;
continue;
}
return false;
} while (!Worklist.empty());
return true;
}
// If we're indexing into an object of a known size, and the outer index is
// not a constant, but having any value but zero would lead to undefined
// behavior, replace it with zero.
//
// For example, if we have:
// @f.a = private unnamed_addr constant [1 x i32] [i32 12], align 4
// ...
// %arrayidx = getelementptr inbounds [1 x i32]* @f.a, i64 0, i64 %x
// ... = load i32* %arrayidx, align 4
// Then we know that we can replace %x in the GEP with i64 0.
//
// FIXME: We could fold any GEP index to zero that would cause UB if it were
// not zero. Currently, we only handle the first such index. Also, we could
// also search through non-zero constant indices if we kept track of the
// offsets those indices implied.
static bool canReplaceGEPIdxWithZero(InstCombiner &IC, GetElementPtrInst *GEPI,
Instruction *MemI, unsigned &Idx) {
if (GEPI->getNumOperands() < 2)
return false;
// Find the first non-zero index of a GEP. If all indices are zero, return
// one past the last index.
auto FirstNZIdx = [](const GetElementPtrInst *GEPI) {
unsigned I = 1;
for (unsigned IE = GEPI->getNumOperands(); I != IE; ++I) {
Value *V = GEPI->getOperand(I);
if (const ConstantInt *CI = dyn_cast<ConstantInt>(V))
if (CI->isZero())
continue;
break;
}
return I;
};
// Skip through initial 'zero' indices, and find the corresponding pointer
// type. See if the next index is not a constant.
Idx = FirstNZIdx(GEPI);
if (Idx == GEPI->getNumOperands())
return false;
if (isa<Constant>(GEPI->getOperand(Idx)))
return false;
SmallVector<Value *, 4> Ops(GEPI->idx_begin(), GEPI->idx_begin() + Idx);
Type *AllocTy = GetElementPtrInst::getIndexedType(
cast<PointerType>(GEPI->getOperand(0)->getType()->getScalarType())
->getElementType(),
Ops);
if (!AllocTy || !AllocTy->isSized())
return false;
const DataLayout &DL = IC.getDataLayout();
uint64_t TyAllocSize = DL.getTypeAllocSize(AllocTy);
// If there are more indices after the one we might replace with a zero, make
// sure they're all non-negative. If any of them are negative, the overall
// address being computed might be before the base address determined by the
// first non-zero index.
auto IsAllNonNegative = [&]() {
for (unsigned i = Idx+1, e = GEPI->getNumOperands(); i != e; ++i) {
bool KnownNonNegative, KnownNegative;
IC.ComputeSignBit(GEPI->getOperand(i), KnownNonNegative,
KnownNegative, 0, MemI);
if (KnownNonNegative)
continue;
return false;
}
return true;
};
// FIXME: If the GEP is not inbounds, and there are extra indices after the
// one we'll replace, those could cause the address computation to wrap
// (rendering the IsAllNonNegative() check below insufficient). We can do
// better, ignoring zero indicies (and other indicies we can prove small
// enough not to wrap).
if (Idx+1 != GEPI->getNumOperands() && !GEPI->isInBounds())
return false;
// Note that isObjectSizeLessThanOrEq will return true only if the pointer is
// also known to be dereferenceable.
return isObjectSizeLessThanOrEq(GEPI->getOperand(0), TyAllocSize, DL) &&
IsAllNonNegative();
}
// If we're indexing into an object with a variable index for the memory
// access, but the object has only one element, we can assume that the index
// will always be zero. If we replace the GEP, return it.
template <typename T>
static Instruction *replaceGEPIdxWithZero(InstCombiner &IC, Value *Ptr,
T &MemI) {
if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(Ptr)) {
unsigned Idx;
if (canReplaceGEPIdxWithZero(IC, GEPI, &MemI, Idx)) {
Instruction *NewGEPI = GEPI->clone();
NewGEPI->setOperand(Idx,
ConstantInt::get(GEPI->getOperand(Idx)->getType(), 0));
NewGEPI->insertBefore(GEPI);
MemI.setOperand(MemI.getPointerOperandIndex(), NewGEPI);
return NewGEPI;
}
}
return nullptr;
}
Instruction *InstCombiner::visitLoadInst(LoadInst &LI) {
Value *Op = LI.getOperand(0);
// Try to canonicalize the loaded type.
if (Instruction *Res = combineLoadToOperationType(*this, LI))
return Res;
// Attempt to improve the alignment.
unsigned KnownAlign = getOrEnforceKnownAlignment(
Op, DL.getPrefTypeAlignment(LI.getType()), DL, &LI, AC, DT);
unsigned LoadAlign = LI.getAlignment();
unsigned EffectiveLoadAlign =
LoadAlign != 0 ? LoadAlign : DL.getABITypeAlignment(LI.getType());
if (KnownAlign > EffectiveLoadAlign)
LI.setAlignment(KnownAlign);
else if (LoadAlign == 0)
LI.setAlignment(EffectiveLoadAlign);
// Replace GEP indices if possible.
if (Instruction *NewGEPI = replaceGEPIdxWithZero(*this, Op, LI)) {
Worklist.Add(NewGEPI);
return &LI;
}
// None of the following transforms are legal for volatile/atomic loads.
// FIXME: Some of it is okay for atomic loads; needs refactoring.
if (!LI.isSimple()) return nullptr;
if (Instruction *Res = unpackLoadToAggregate(*this, LI))
return Res;
// Do really simple store-to-load forwarding and load CSE, to catch cases
// where there are several consecutive memory accesses to the same location,
// separated by a few arithmetic operations.
BasicBlock::iterator BBI = &LI;
AAMDNodes AATags;
if (Value *AvailableVal = FindAvailableLoadedValue(Op, LI.getParent(), BBI,
6, AA, &AATags)) {
if (LoadInst *NLI = dyn_cast<LoadInst>(AvailableVal)) {
unsigned KnownIDs[] = {
LLVMContext::MD_tbaa,
LLVMContext::MD_alias_scope,
LLVMContext::MD_noalias,
LLVMContext::MD_range,
LLVMContext::MD_invariant_load,
LLVMContext::MD_nonnull,
};
combineMetadata(NLI, &LI, KnownIDs);
};
return ReplaceInstUsesWith(
LI, Builder->CreateBitOrPointerCast(AvailableVal, LI.getType(),
LI.getName() + ".cast"));
}
// load(gep null, ...) -> unreachable
if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(Op)) {
const Value *GEPI0 = GEPI->getOperand(0);
// TODO: Consider a target hook for valid address spaces for this xform.
if (isa<ConstantPointerNull>(GEPI0) && GEPI->getPointerAddressSpace() == 0){
// Insert a new store to null instruction before the load to indicate
// that this code is not reachable. We do this instead of inserting
// an unreachable instruction directly because we cannot modify the
// CFG.
new StoreInst(UndefValue::get(LI.getType()),
Constant::getNullValue(Op->getType()), &LI);
return ReplaceInstUsesWith(LI, UndefValue::get(LI.getType()));
}
}
// load null/undef -> unreachable
// TODO: Consider a target hook for valid address spaces for this xform.
if (isa<UndefValue>(Op) ||
(isa<ConstantPointerNull>(Op) && LI.getPointerAddressSpace() == 0)) {
// Insert a new store to null instruction before the load to indicate that
// this code is not reachable. We do this instead of inserting an
// unreachable instruction directly because we cannot modify the CFG.
new StoreInst(UndefValue::get(LI.getType()),
Constant::getNullValue(Op->getType()), &LI);
return ReplaceInstUsesWith(LI, UndefValue::get(LI.getType()));
}
if (Op->hasOneUse()) {
// Change select and PHI nodes to select values instead of addresses: this
// helps alias analysis out a lot, allows many others simplifications, and
// exposes redundancy in the code.
//
// Note that we cannot do the transformation unless we know that the
// introduced loads cannot trap! Something like this is valid as long as
// the condition is always false: load (select bool %C, int* null, int* %G),
// but it would not be valid if we transformed it to load from null
// unconditionally.
//
if (SelectInst *SI = dyn_cast<SelectInst>(Op)) {
// load (select (Cond, &V1, &V2)) --> select(Cond, load &V1, load &V2).
unsigned Align = LI.getAlignment();
if (isSafeToLoadUnconditionally(SI->getOperand(1), SI, Align) &&
isSafeToLoadUnconditionally(SI->getOperand(2), SI, Align)) {
LoadInst *V1 = Builder->CreateLoad(SI->getOperand(1),
SI->getOperand(1)->getName()+".val");
LoadInst *V2 = Builder->CreateLoad(SI->getOperand(2),
SI->getOperand(2)->getName()+".val");
V1->setAlignment(Align);
V2->setAlignment(Align);
return SelectInst::Create(SI->getCondition(), V1, V2);
}
// load (select (cond, null, P)) -> load P
if (isa<ConstantPointerNull>(SI->getOperand(1)) &&
LI.getPointerAddressSpace() == 0) {
LI.setOperand(0, SI->getOperand(2));
return &LI;
}
// load (select (cond, P, null)) -> load P
if (isa<ConstantPointerNull>(SI->getOperand(2)) &&
LI.getPointerAddressSpace() == 0) {
LI.setOperand(0, SI->getOperand(1));
return &LI;
}
}
}
return nullptr;
}
/// \brief Combine stores to match the type of value being stored.
///
/// The core idea here is that the memory does not have any intrinsic type and
/// where we can we should match the type of a store to the type of value being
/// stored.
///
/// However, this routine must never change the width of a store or the number of
/// stores as that would introduce a semantic change. This combine is expected to
/// be a semantic no-op which just allows stores to more closely model the types
/// of their incoming values.
///
/// Currently, we also refuse to change the precise type used for an atomic or
/// volatile store. This is debatable, and might be reasonable to change later.
/// However, it is risky in case some backend or other part of LLVM is relying
/// on the exact type stored to select appropriate atomic operations.
///
/// \returns true if the store was successfully combined away. This indicates
/// the caller must erase the store instruction. We have to let the caller erase
/// the store instruction sas otherwise there is no way to signal whether it was
/// combined or not: IC.EraseInstFromFunction returns a null pointer.
static bool combineStoreToValueType(InstCombiner &IC, StoreInst &SI) {
// FIXME: We could probably with some care handle both volatile and atomic
// stores here but it isn't clear that this is important.
if (!SI.isSimple())
return false;
Value *V = SI.getValueOperand();
// Fold away bit casts of the stored value by storing the original type.
if (auto *BC = dyn_cast<BitCastInst>(V)) {
V = BC->getOperand(0);
combineStoreToNewValue(IC, SI, V);
return true;
}
// FIXME: We should also canonicalize loads of vectors when their elements are
// cast to other types.
return false;
}
static bool unpackStoreToAggregate(InstCombiner &IC, StoreInst &SI) {
// FIXME: We could probably with some care handle both volatile and atomic
// stores here but it isn't clear that this is important.
if (!SI.isSimple())
return false;
Value *V = SI.getValueOperand();
Type *T = V->getType();
if (!T->isAggregateType())
return false;
if (auto *ST = dyn_cast<StructType>(T)) {
// If the struct only have one element, we unpack.
if (ST->getNumElements() == 1
&& false // HLSL Change - avoid unpack dxil types.
) {
V = IC.Builder->CreateExtractValue(V, 0);
combineStoreToNewValue(IC, SI, V);
return true;
}
}
if (auto *AT = dyn_cast<ArrayType>(T)) {
// If the array only have one element, we unpack.
if (AT->getNumElements() == 1) {
V = IC.Builder->CreateExtractValue(V, 0);
combineStoreToNewValue(IC, SI, V);
return true;
}
}
return false;
}
/// equivalentAddressValues - Test if A and B will obviously have the same
/// value. This includes recognizing that %t0 and %t1 will have the same
/// value in code like this:
/// %t0 = getelementptr \@a, 0, 3
/// store i32 0, i32* %t0
/// %t1 = getelementptr \@a, 0, 3
/// %t2 = load i32* %t1
///
static bool equivalentAddressValues(Value *A, Value *B) {
// Test if the values are trivially equivalent.
if (A == B) return true;
// Test if the values come form identical arithmetic instructions.
// This uses isIdenticalToWhenDefined instead of isIdenticalTo because
// its only used to compare two uses within the same basic block, which
// means that they'll always either have the same value or one of them
// will have an undefined value.
if (isa<BinaryOperator>(A) ||
isa<CastInst>(A) ||
isa<PHINode>(A) ||
isa<GetElementPtrInst>(A))
if (Instruction *BI = dyn_cast<Instruction>(B))
if (cast<Instruction>(A)->isIdenticalToWhenDefined(BI))
return true;
// Otherwise they may not be equivalent.
return false;
}
Instruction *InstCombiner::visitStoreInst(StoreInst &SI) {
Value *Val = SI.getOperand(0);
Value *Ptr = SI.getOperand(1);
// Try to canonicalize the stored type.
if (combineStoreToValueType(*this, SI))
return EraseInstFromFunction(SI);
// Attempt to improve the alignment.
unsigned KnownAlign = getOrEnforceKnownAlignment(
Ptr, DL.getPrefTypeAlignment(Val->getType()), DL, &SI, AC, DT);
unsigned StoreAlign = SI.getAlignment();
unsigned EffectiveStoreAlign =
StoreAlign != 0 ? StoreAlign : DL.getABITypeAlignment(Val->getType());
if (KnownAlign > EffectiveStoreAlign)
SI.setAlignment(KnownAlign);
else if (StoreAlign == 0)
SI.setAlignment(EffectiveStoreAlign);
// Try to canonicalize the stored type.
if (unpackStoreToAggregate(*this, SI))
return EraseInstFromFunction(SI);
// Replace GEP indices if possible.
if (Instruction *NewGEPI = replaceGEPIdxWithZero(*this, Ptr, SI)) {
Worklist.Add(NewGEPI);
return &SI;
}
// Don't hack volatile/atomic stores.
// FIXME: Some bits are legal for atomic stores; needs refactoring.
if (!SI.isSimple()) return nullptr;
// If the RHS is an alloca with a single use, zapify the store, making the
// alloca dead.
if (Ptr->hasOneUse()) {
if (isa<AllocaInst>(Ptr))
return EraseInstFromFunction(SI);
if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Ptr)) {
if (isa<AllocaInst>(GEP->getOperand(0))) {
if (GEP->getOperand(0)->hasOneUse())
return EraseInstFromFunction(SI);
}
}
}
// Do really simple DSE, to catch cases where there are several consecutive
// stores to the same location, separated by a few arithmetic operations. This
// situation often occurs with bitfield accesses.
BasicBlock::iterator BBI = &SI;
for (unsigned ScanInsts = 6; BBI != SI.getParent()->begin() && ScanInsts;
--ScanInsts) {
--BBI;
// Don't count debug info directives, lest they affect codegen,
// and we skip pointer-to-pointer bitcasts, which are NOPs.
if (isa<DbgInfoIntrinsic>(BBI) ||
(isa<BitCastInst>(BBI) && BBI->getType()->isPointerTy())) {
ScanInsts++;
continue;
}
if (StoreInst *PrevSI = dyn_cast<StoreInst>(BBI)) {
// Prev store isn't volatile, and stores to the same location?
if (PrevSI->isSimple() && equivalentAddressValues(PrevSI->getOperand(1),
SI.getOperand(1))) {
++NumDeadStore;
++BBI;
EraseInstFromFunction(*PrevSI);
continue;
}
break;
}
// If this is a load, we have to stop. However, if the loaded value is from
// the pointer we're loading and is producing the pointer we're storing,
// then *this* store is dead (X = load P; store X -> P).
if (LoadInst *LI = dyn_cast<LoadInst>(BBI)) {
if (LI == Val && equivalentAddressValues(LI->getOperand(0), Ptr) &&
LI->isSimple())
return EraseInstFromFunction(SI);
// Otherwise, this is a load from some other location. Stores before it
// may not be dead.
break;
}
// Don't skip over loads or things that can modify memory.
if (BBI->mayWriteToMemory() || BBI->mayReadFromMemory())
break;
}
// store X, null -> turns into 'unreachable' in SimplifyCFG
if (isa<ConstantPointerNull>(Ptr) && SI.getPointerAddressSpace() == 0) {
if (!isa<UndefValue>(Val)) {
SI.setOperand(0, UndefValue::get(Val->getType()));
if (Instruction *U = dyn_cast<Instruction>(Val))
Worklist.Add(U); // Dropped a use.
}
return nullptr; // Do not modify these!
}
// store undef, Ptr -> noop
if (isa<UndefValue>(Val))
return EraseInstFromFunction(SI);
// If this store is the last instruction in the basic block (possibly
// excepting debug info instructions), and if the block ends with an
// unconditional branch, try to move it to the successor block.
BBI = &SI;
do {
++BBI;
} while (isa<DbgInfoIntrinsic>(BBI) ||
(isa<BitCastInst>(BBI) && BBI->getType()->isPointerTy()));
if (BranchInst *BI = dyn_cast<BranchInst>(BBI))
if (BI->isUnconditional())
if (SimplifyStoreAtEndOfBlock(SI))
return nullptr; // xform done!
return nullptr;
}
/// SimplifyStoreAtEndOfBlock - Turn things like:
/// if () { *P = v1; } else { *P = v2 }
/// into a phi node with a store in the successor.
///
/// Simplify things like:
/// *P = v1; if () { *P = v2; }
/// into a phi node with a store in the successor.
///
bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) {
BasicBlock *StoreBB = SI.getParent();
// Check to see if the successor block has exactly two incoming edges. If
// so, see if the other predecessor contains a store to the same location.
// if so, insert a PHI node (if needed) and move the stores down.
BasicBlock *DestBB = StoreBB->getTerminator()->getSuccessor(0);
// Determine whether Dest has exactly two predecessors and, if so, compute
// the other predecessor.
pred_iterator PI = pred_begin(DestBB);
BasicBlock *P = *PI;
BasicBlock *OtherBB = nullptr;
if (P != StoreBB)
OtherBB = P;
if (++PI == pred_end(DestBB))
return false;
P = *PI;
if (P != StoreBB) {
if (OtherBB)
return false;
OtherBB = P;
}
if (++PI != pred_end(DestBB))
return false;
// Bail out if all the relevant blocks aren't distinct (this can happen,
// for example, if SI is in an infinite loop)
if (StoreBB == DestBB || OtherBB == DestBB)
return false;
// Verify that the other block ends in a branch and is not otherwise empty.
BasicBlock::iterator BBI = OtherBB->getTerminator();
BranchInst *OtherBr = dyn_cast<BranchInst>(BBI);
if (!OtherBr || BBI == OtherBB->begin())
return false;
// If the other block ends in an unconditional branch, check for the 'if then
// else' case. there is an instruction before the branch.
StoreInst *OtherStore = nullptr;
if (OtherBr->isUnconditional()) {
--BBI;
// Skip over debugging info.
while (isa<DbgInfoIntrinsic>(BBI) ||
(isa<BitCastInst>(BBI) && BBI->getType()->isPointerTy())) {
if (BBI==OtherBB->begin())
return false;
--BBI;
}
// If this isn't a store, isn't a store to the same location, or is not the
// right kind of store, bail out.
OtherStore = dyn_cast<StoreInst>(BBI);
if (!OtherStore || OtherStore->getOperand(1) != SI.getOperand(1) ||
!SI.isSameOperationAs(OtherStore))
return false;
} else {
// Otherwise, the other block ended with a conditional branch. If one of the
// destinations is StoreBB, then we have the if/then case.
if (OtherBr->getSuccessor(0) != StoreBB &&
OtherBr->getSuccessor(1) != StoreBB)
return false;
// Okay, we know that OtherBr now goes to Dest and StoreBB, so this is an
// if/then triangle. See if there is a store to the same ptr as SI that
// lives in OtherBB.
for (;; --BBI) {
// Check to see if we find the matching store.
if ((OtherStore = dyn_cast<StoreInst>(BBI))) {
if (OtherStore->getOperand(1) != SI.getOperand(1) ||
!SI.isSameOperationAs(OtherStore))
return false;
break;
}
// If we find something that may be using or overwriting the stored
// value, or if we run out of instructions, we can't do the xform.
if (BBI->mayReadFromMemory() || BBI->mayWriteToMemory() ||
BBI == OtherBB->begin())
return false;
}
// In order to eliminate the store in OtherBr, we have to
// make sure nothing reads or overwrites the stored value in
// StoreBB.
for (BasicBlock::iterator I = StoreBB->begin(); &*I != &SI; ++I) {
// FIXME: This should really be AA driven.
if (I->mayReadFromMemory() || I->mayWriteToMemory())
return false;
}
}
// Insert a PHI node now if we need it.
Value *MergedVal = OtherStore->getOperand(0);
if (MergedVal != SI.getOperand(0)) {
PHINode *PN = PHINode::Create(MergedVal->getType(), 2, "storemerge");
PN->addIncoming(SI.getOperand(0), SI.getParent());
PN->addIncoming(OtherStore->getOperand(0), OtherBB);
MergedVal = InsertNewInstBefore(PN, DestBB->front());
}
// Advance to a place where it is safe to insert the new store and
// insert it.
BBI = DestBB->getFirstInsertionPt();
StoreInst *NewSI = new StoreInst(MergedVal, SI.getOperand(1),
SI.isVolatile(),
SI.getAlignment(),
SI.getOrdering(),
SI.getSynchScope());
InsertNewInstBefore(NewSI, *BBI);
NewSI->setDebugLoc(OtherStore->getDebugLoc());
// If the two stores had AA tags, merge them.
AAMDNodes AATags;
SI.getAAMetadata(AATags);
if (AATags) {
OtherStore->getAAMetadata(AATags, /* Merge = */ true);
NewSI->setAAMetadata(AATags);
}
// Nuke the old stores.
EraseInstFromFunction(SI);
EraseInstFromFunction(*OtherStore);
return true;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp | //===- InstCombineSimplifyDemanded.cpp ------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains logic for simplifying instructions based on information
// about how they are used.
//
//===----------------------------------------------------------------------===//
#include "InstCombineInternal.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/PatternMatch.h"
using namespace llvm;
using namespace llvm::PatternMatch;
#define DEBUG_TYPE "instcombine"
/// ShrinkDemandedConstant - Check to see if the specified operand of the
/// specified instruction is a constant integer. If so, check to see if there
/// are any bits set in the constant that are not demanded. If so, shrink the
/// constant and return true.
static bool ShrinkDemandedConstant(Instruction *I, unsigned OpNo,
APInt Demanded) {
assert(I && "No instruction?");
assert(OpNo < I->getNumOperands() && "Operand index too large");
// If the operand is not a constant integer, nothing to do.
ConstantInt *OpC = dyn_cast<ConstantInt>(I->getOperand(OpNo));
if (!OpC) return false;
// If there are no bits set that aren't demanded, nothing to do.
Demanded = Demanded.zextOrTrunc(OpC->getValue().getBitWidth());
if ((~Demanded & OpC->getValue()) == 0)
return false;
// This instruction is producing bits that are not demanded. Shrink the RHS.
Demanded &= OpC->getValue();
I->setOperand(OpNo, ConstantInt::get(OpC->getType(), Demanded));
return true;
}
/// SimplifyDemandedInstructionBits - Inst is an integer instruction that
/// SimplifyDemandedBits knows about. See if the instruction has any
/// properties that allow us to simplify its operands.
bool InstCombiner::SimplifyDemandedInstructionBits(Instruction &Inst) {
unsigned BitWidth = Inst.getType()->getScalarSizeInBits();
APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
APInt DemandedMask(APInt::getAllOnesValue(BitWidth));
Value *V = SimplifyDemandedUseBits(&Inst, DemandedMask, KnownZero, KnownOne,
0, &Inst);
if (!V) return false;
if (V == &Inst) return true;
ReplaceInstUsesWith(Inst, V);
return true;
}
/// SimplifyDemandedBits - This form of SimplifyDemandedBits simplifies the
/// specified instruction operand if possible, updating it in place. It returns
/// true if it made any change and false otherwise.
bool InstCombiner::SimplifyDemandedBits(Use &U, APInt DemandedMask,
APInt &KnownZero, APInt &KnownOne,
unsigned Depth) {
auto *UserI = dyn_cast<Instruction>(U.getUser());
Value *NewVal = SimplifyDemandedUseBits(U.get(), DemandedMask, KnownZero,
KnownOne, Depth, UserI);
if (!NewVal) return false;
U = NewVal;
return true;
}
/// SimplifyDemandedUseBits - This function attempts to replace V with a simpler
/// value based on the demanded bits. When this function is called, it is known
/// that only the bits set in DemandedMask of the result of V are ever used
/// downstream. Consequently, depending on the mask and V, it may be possible
/// to replace V with a constant or one of its operands. In such cases, this
/// function does the replacement and returns true. In all other cases, it
/// returns false after analyzing the expression and setting KnownOne and known
/// to be one in the expression. KnownZero contains all the bits that are known
/// to be zero in the expression. These are provided to potentially allow the
/// caller (which might recursively be SimplifyDemandedBits itself) to simplify
/// the expression. KnownOne and KnownZero always follow the invariant that
/// KnownOne & KnownZero == 0. That is, a bit can't be both 1 and 0. Note that
/// the bits in KnownOne and KnownZero may only be accurate for those bits set
/// in DemandedMask. Note also that the bitwidth of V, DemandedMask, KnownZero
/// and KnownOne must all be the same.
///
/// This returns null if it did not change anything and it permits no
/// simplification. This returns V itself if it did some simplification of V's
/// operands based on the information about what bits are demanded. This returns
/// some other non-null value if it found out that V is equal to another value
/// in the context where the specified bits are demanded, but not for all users.
Value *InstCombiner::SimplifyDemandedUseBits(Value *V, APInt DemandedMask,
APInt &KnownZero, APInt &KnownOne,
unsigned Depth,
Instruction *CxtI) {
assert(V != nullptr && "Null pointer of Value???");
assert(Depth <= 6 && "Limit Search Depth");
uint32_t BitWidth = DemandedMask.getBitWidth();
Type *VTy = V->getType();
assert(
(!VTy->isIntOrIntVectorTy() || VTy->getScalarSizeInBits() == BitWidth) &&
KnownZero.getBitWidth() == BitWidth &&
KnownOne.getBitWidth() == BitWidth &&
"Value *V, DemandedMask, KnownZero and KnownOne "
"must have same BitWidth");
if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
// We know all of the bits for a constant!
KnownOne = CI->getValue() & DemandedMask;
KnownZero = ~KnownOne & DemandedMask;
return nullptr;
}
if (isa<ConstantPointerNull>(V)) {
// We know all of the bits for a constant!
KnownOne.clearAllBits();
KnownZero = DemandedMask;
return nullptr;
}
KnownZero.clearAllBits();
KnownOne.clearAllBits();
if (DemandedMask == 0) { // Not demanding any bits from V.
if (isa<UndefValue>(V))
return nullptr;
return UndefValue::get(VTy);
}
if (Depth == 6) // Limit search depth.
return nullptr;
APInt LHSKnownZero(BitWidth, 0), LHSKnownOne(BitWidth, 0);
APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
Instruction *I = dyn_cast<Instruction>(V);
if (!I) {
computeKnownBits(V, KnownZero, KnownOne, Depth, CxtI);
return nullptr; // Only analyze instructions.
}
// If there are multiple uses of this value and we aren't at the root, then
// we can't do any simplifications of the operands, because DemandedMask
// only reflects the bits demanded by *one* of the users.
if (Depth != 0 && !I->hasOneUse()) {
// Despite the fact that we can't simplify this instruction in all User's
// context, we can at least compute the knownzero/knownone bits, and we can
// do simplifications that apply to *just* the one user if we know that
// this instruction has a simpler value in that context.
if (I->getOpcode() == Instruction::And) {
// If either the LHS or the RHS are Zero, the result is zero.
computeKnownBits(I->getOperand(1), RHSKnownZero, RHSKnownOne, Depth + 1,
CxtI);
computeKnownBits(I->getOperand(0), LHSKnownZero, LHSKnownOne, Depth + 1,
CxtI);
// If all of the demanded bits are known 1 on one side, return the other.
// These bits cannot contribute to the result of the 'and' in this
// context.
if ((DemandedMask & ~LHSKnownZero & RHSKnownOne) ==
(DemandedMask & ~LHSKnownZero))
return I->getOperand(0);
if ((DemandedMask & ~RHSKnownZero & LHSKnownOne) ==
(DemandedMask & ~RHSKnownZero))
return I->getOperand(1);
// If all of the demanded bits in the inputs are known zeros, return zero.
if ((DemandedMask & (RHSKnownZero|LHSKnownZero)) == DemandedMask)
return Constant::getNullValue(VTy);
} else if (I->getOpcode() == Instruction::Or) {
// We can simplify (X|Y) -> X or Y in the user's context if we know that
// only bits from X or Y are demanded.
// If either the LHS or the RHS are One, the result is One.
computeKnownBits(I->getOperand(1), RHSKnownZero, RHSKnownOne, Depth + 1,
CxtI);
computeKnownBits(I->getOperand(0), LHSKnownZero, LHSKnownOne, Depth + 1,
CxtI);
// If all of the demanded bits are known zero on one side, return the
// other. These bits cannot contribute to the result of the 'or' in this
// context.
if ((DemandedMask & ~LHSKnownOne & RHSKnownZero) ==
(DemandedMask & ~LHSKnownOne))
return I->getOperand(0);
if ((DemandedMask & ~RHSKnownOne & LHSKnownZero) ==
(DemandedMask & ~RHSKnownOne))
return I->getOperand(1);
// If all of the potentially set bits on one side are known to be set on
// the other side, just use the 'other' side.
if ((DemandedMask & (~RHSKnownZero) & LHSKnownOne) ==
(DemandedMask & (~RHSKnownZero)))
return I->getOperand(0);
if ((DemandedMask & (~LHSKnownZero) & RHSKnownOne) ==
(DemandedMask & (~LHSKnownZero)))
return I->getOperand(1);
} else if (I->getOpcode() == Instruction::Xor) {
// We can simplify (X^Y) -> X or Y in the user's context if we know that
// only bits from X or Y are demanded.
computeKnownBits(I->getOperand(1), RHSKnownZero, RHSKnownOne, Depth + 1,
CxtI);
computeKnownBits(I->getOperand(0), LHSKnownZero, LHSKnownOne, Depth + 1,
CxtI);
// If all of the demanded bits are known zero on one side, return the
// other.
if ((DemandedMask & RHSKnownZero) == DemandedMask)
return I->getOperand(0);
if ((DemandedMask & LHSKnownZero) == DemandedMask)
return I->getOperand(1);
}
// Compute the KnownZero/KnownOne bits to simplify things downstream.
computeKnownBits(I, KnownZero, KnownOne, Depth, CxtI);
return nullptr;
}
// If this is the root being simplified, allow it to have multiple uses,
// just set the DemandedMask to all bits so that we can try to simplify the
// operands. This allows visitTruncInst (for example) to simplify the
// operand of a trunc without duplicating all the logic below.
if (Depth == 0 && !V->hasOneUse())
DemandedMask = APInt::getAllOnesValue(BitWidth);
switch (I->getOpcode()) {
default:
computeKnownBits(I, KnownZero, KnownOne, Depth, CxtI);
break;
case Instruction::And:
// If either the LHS or the RHS are Zero, the result is zero.
if (SimplifyDemandedBits(I->getOperandUse(1), DemandedMask, RHSKnownZero,
RHSKnownOne, Depth + 1) ||
SimplifyDemandedBits(I->getOperandUse(0), DemandedMask & ~RHSKnownZero,
LHSKnownZero, LHSKnownOne, Depth + 1))
return I;
assert(!(RHSKnownZero & RHSKnownOne) && "Bits known to be one AND zero?");
assert(!(LHSKnownZero & LHSKnownOne) && "Bits known to be one AND zero?");
// If the client is only demanding bits that we know, return the known
// constant.
if ((DemandedMask & ((RHSKnownZero | LHSKnownZero)|
(RHSKnownOne & LHSKnownOne))) == DemandedMask)
return Constant::getIntegerValue(VTy, RHSKnownOne & LHSKnownOne);
// If all of the demanded bits are known 1 on one side, return the other.
// These bits cannot contribute to the result of the 'and'.
if ((DemandedMask & ~LHSKnownZero & RHSKnownOne) ==
(DemandedMask & ~LHSKnownZero))
return I->getOperand(0);
if ((DemandedMask & ~RHSKnownZero & LHSKnownOne) ==
(DemandedMask & ~RHSKnownZero))
return I->getOperand(1);
// If all of the demanded bits in the inputs are known zeros, return zero.
if ((DemandedMask & (RHSKnownZero|LHSKnownZero)) == DemandedMask)
return Constant::getNullValue(VTy);
// If the RHS is a constant, see if we can simplify it.
if (ShrinkDemandedConstant(I, 1, DemandedMask & ~LHSKnownZero))
return I;
// Output known-1 bits are only known if set in both the LHS & RHS.
KnownOne = RHSKnownOne & LHSKnownOne;
// Output known-0 are known to be clear if zero in either the LHS | RHS.
KnownZero = RHSKnownZero | LHSKnownZero;
break;
case Instruction::Or:
// If either the LHS or the RHS are One, the result is One.
if (SimplifyDemandedBits(I->getOperandUse(1), DemandedMask, RHSKnownZero,
RHSKnownOne, Depth + 1) ||
SimplifyDemandedBits(I->getOperandUse(0), DemandedMask & ~RHSKnownOne,
LHSKnownZero, LHSKnownOne, Depth + 1))
return I;
assert(!(RHSKnownZero & RHSKnownOne) && "Bits known to be one AND zero?");
assert(!(LHSKnownZero & LHSKnownOne) && "Bits known to be one AND zero?");
// If the client is only demanding bits that we know, return the known
// constant.
if ((DemandedMask & ((RHSKnownZero & LHSKnownZero)|
(RHSKnownOne | LHSKnownOne))) == DemandedMask)
return Constant::getIntegerValue(VTy, RHSKnownOne | LHSKnownOne);
// If all of the demanded bits are known zero on one side, return the other.
// These bits cannot contribute to the result of the 'or'.
if ((DemandedMask & ~LHSKnownOne & RHSKnownZero) ==
(DemandedMask & ~LHSKnownOne))
return I->getOperand(0);
if ((DemandedMask & ~RHSKnownOne & LHSKnownZero) ==
(DemandedMask & ~RHSKnownOne))
return I->getOperand(1);
// If all of the potentially set bits on one side are known to be set on
// the other side, just use the 'other' side.
if ((DemandedMask & (~RHSKnownZero) & LHSKnownOne) ==
(DemandedMask & (~RHSKnownZero)))
return I->getOperand(0);
if ((DemandedMask & (~LHSKnownZero) & RHSKnownOne) ==
(DemandedMask & (~LHSKnownZero)))
return I->getOperand(1);
// If the RHS is a constant, see if we can simplify it.
if (ShrinkDemandedConstant(I, 1, DemandedMask))
return I;
// Output known-0 bits are only known if clear in both the LHS & RHS.
KnownZero = RHSKnownZero & LHSKnownZero;
// Output known-1 are known to be set if set in either the LHS | RHS.
KnownOne = RHSKnownOne | LHSKnownOne;
break;
case Instruction::Xor: {
if (SimplifyDemandedBits(I->getOperandUse(1), DemandedMask, RHSKnownZero,
RHSKnownOne, Depth + 1) ||
SimplifyDemandedBits(I->getOperandUse(0), DemandedMask, LHSKnownZero,
LHSKnownOne, Depth + 1))
return I;
assert(!(RHSKnownZero & RHSKnownOne) && "Bits known to be one AND zero?");
assert(!(LHSKnownZero & LHSKnownOne) && "Bits known to be one AND zero?");
// Output known-0 bits are known if clear or set in both the LHS & RHS.
APInt IKnownZero = (RHSKnownZero & LHSKnownZero) |
(RHSKnownOne & LHSKnownOne);
// Output known-1 are known to be set if set in only one of the LHS, RHS.
APInt IKnownOne = (RHSKnownZero & LHSKnownOne) |
(RHSKnownOne & LHSKnownZero);
// If the client is only demanding bits that we know, return the known
// constant.
if ((DemandedMask & (IKnownZero|IKnownOne)) == DemandedMask)
return Constant::getIntegerValue(VTy, IKnownOne);
// If all of the demanded bits are known zero on one side, return the other.
// These bits cannot contribute to the result of the 'xor'.
if ((DemandedMask & RHSKnownZero) == DemandedMask)
return I->getOperand(0);
if ((DemandedMask & LHSKnownZero) == DemandedMask)
return I->getOperand(1);
// If all of the demanded bits are known to be zero on one side or the
// other, turn this into an *inclusive* or.
// e.g. (A & C1)^(B & C2) -> (A & C1)|(B & C2) iff C1&C2 == 0
if ((DemandedMask & ~RHSKnownZero & ~LHSKnownZero) == 0) {
Instruction *Or =
BinaryOperator::CreateOr(I->getOperand(0), I->getOperand(1),
I->getName());
return InsertNewInstWith(Or, *I);
}
// If all of the demanded bits on one side are known, and all of the set
// bits on that side are also known to be set on the other side, turn this
// into an AND, as we know the bits will be cleared.
// e.g. (X | C1) ^ C2 --> (X | C1) & ~C2 iff (C1&C2) == C2
if ((DemandedMask & (RHSKnownZero|RHSKnownOne)) == DemandedMask) {
// all known
if ((RHSKnownOne & LHSKnownOne) == RHSKnownOne) {
Constant *AndC = Constant::getIntegerValue(VTy,
~RHSKnownOne & DemandedMask);
Instruction *And = BinaryOperator::CreateAnd(I->getOperand(0), AndC);
return InsertNewInstWith(And, *I);
}
}
// If the RHS is a constant, see if we can simplify it.
// FIXME: for XOR, we prefer to force bits to 1 if they will make a -1.
if (ShrinkDemandedConstant(I, 1, DemandedMask))
return I;
// If our LHS is an 'and' and if it has one use, and if any of the bits we
// are flipping are known to be set, then the xor is just resetting those
// bits to zero. We can just knock out bits from the 'and' and the 'xor',
// simplifying both of them.
if (Instruction *LHSInst = dyn_cast<Instruction>(I->getOperand(0)))
if (LHSInst->getOpcode() == Instruction::And && LHSInst->hasOneUse() &&
isa<ConstantInt>(I->getOperand(1)) &&
isa<ConstantInt>(LHSInst->getOperand(1)) &&
(LHSKnownOne & RHSKnownOne & DemandedMask) != 0) {
ConstantInt *AndRHS = cast<ConstantInt>(LHSInst->getOperand(1));
ConstantInt *XorRHS = cast<ConstantInt>(I->getOperand(1));
APInt NewMask = ~(LHSKnownOne & RHSKnownOne & DemandedMask);
Constant *AndC =
ConstantInt::get(I->getType(), NewMask & AndRHS->getValue());
Instruction *NewAnd = BinaryOperator::CreateAnd(I->getOperand(0), AndC);
InsertNewInstWith(NewAnd, *I);
Constant *XorC =
ConstantInt::get(I->getType(), NewMask & XorRHS->getValue());
Instruction *NewXor = BinaryOperator::CreateXor(NewAnd, XorC);
return InsertNewInstWith(NewXor, *I);
}
// Output known-0 bits are known if clear or set in both the LHS & RHS.
KnownZero= (RHSKnownZero & LHSKnownZero) | (RHSKnownOne & LHSKnownOne);
// Output known-1 are known to be set if set in only one of the LHS, RHS.
KnownOne = (RHSKnownZero & LHSKnownOne) | (RHSKnownOne & LHSKnownZero);
break;
}
case Instruction::Select:
// If this is a select as part of a min/max pattern, don't simplify any
// further in case we break the structure.
Value *LHS, *RHS;
if (matchSelectPattern(I, LHS, RHS) != SPF_UNKNOWN)
return nullptr;
if (SimplifyDemandedBits(I->getOperandUse(2), DemandedMask, RHSKnownZero,
RHSKnownOne, Depth + 1) ||
SimplifyDemandedBits(I->getOperandUse(1), DemandedMask, LHSKnownZero,
LHSKnownOne, Depth + 1))
return I;
assert(!(RHSKnownZero & RHSKnownOne) && "Bits known to be one AND zero?");
assert(!(LHSKnownZero & LHSKnownOne) && "Bits known to be one AND zero?");
// If the operands are constants, see if we can simplify them.
if (ShrinkDemandedConstant(I, 1, DemandedMask) ||
ShrinkDemandedConstant(I, 2, DemandedMask))
return I;
// Only known if known in both the LHS and RHS.
KnownOne = RHSKnownOne & LHSKnownOne;
KnownZero = RHSKnownZero & LHSKnownZero;
break;
case Instruction::Trunc: {
unsigned truncBf = I->getOperand(0)->getType()->getScalarSizeInBits();
DemandedMask = DemandedMask.zext(truncBf);
KnownZero = KnownZero.zext(truncBf);
KnownOne = KnownOne.zext(truncBf);
if (SimplifyDemandedBits(I->getOperandUse(0), DemandedMask, KnownZero,
KnownOne, Depth + 1))
return I;
DemandedMask = DemandedMask.trunc(BitWidth);
KnownZero = KnownZero.trunc(BitWidth);
KnownOne = KnownOne.trunc(BitWidth);
assert(!(KnownZero & KnownOne) && "Bits known to be one AND zero?");
break;
}
case Instruction::BitCast:
if (!I->getOperand(0)->getType()->isIntOrIntVectorTy())
return nullptr; // vector->int or fp->int?
if (VectorType *DstVTy = dyn_cast<VectorType>(I->getType())) {
if (VectorType *SrcVTy =
dyn_cast<VectorType>(I->getOperand(0)->getType())) {
if (DstVTy->getNumElements() != SrcVTy->getNumElements())
// Don't touch a bitcast between vectors of different element counts.
return nullptr;
} else
// Don't touch a scalar-to-vector bitcast.
return nullptr;
} else if (I->getOperand(0)->getType()->isVectorTy())
// Don't touch a vector-to-scalar bitcast.
return nullptr;
if (SimplifyDemandedBits(I->getOperandUse(0), DemandedMask, KnownZero,
KnownOne, Depth + 1))
return I;
assert(!(KnownZero & KnownOne) && "Bits known to be one AND zero?");
break;
case Instruction::ZExt: {
// Compute the bits in the result that are not present in the input.
unsigned SrcBitWidth =I->getOperand(0)->getType()->getScalarSizeInBits();
DemandedMask = DemandedMask.trunc(SrcBitWidth);
KnownZero = KnownZero.trunc(SrcBitWidth);
KnownOne = KnownOne.trunc(SrcBitWidth);
if (SimplifyDemandedBits(I->getOperandUse(0), DemandedMask, KnownZero,
KnownOne, Depth + 1))
return I;
DemandedMask = DemandedMask.zext(BitWidth);
KnownZero = KnownZero.zext(BitWidth);
KnownOne = KnownOne.zext(BitWidth);
assert(!(KnownZero & KnownOne) && "Bits known to be one AND zero?");
// The top bits are known to be zero.
KnownZero |= APInt::getHighBitsSet(BitWidth, BitWidth - SrcBitWidth);
break;
}
case Instruction::SExt: {
// Compute the bits in the result that are not present in the input.
unsigned SrcBitWidth =I->getOperand(0)->getType()->getScalarSizeInBits();
APInt InputDemandedBits = DemandedMask &
APInt::getLowBitsSet(BitWidth, SrcBitWidth);
APInt NewBits(APInt::getHighBitsSet(BitWidth, BitWidth - SrcBitWidth));
// If any of the sign extended bits are demanded, we know that the sign
// bit is demanded.
if ((NewBits & DemandedMask) != 0)
InputDemandedBits.setBit(SrcBitWidth-1);
InputDemandedBits = InputDemandedBits.trunc(SrcBitWidth);
KnownZero = KnownZero.trunc(SrcBitWidth);
KnownOne = KnownOne.trunc(SrcBitWidth);
if (SimplifyDemandedBits(I->getOperandUse(0), InputDemandedBits, KnownZero,
KnownOne, Depth + 1))
return I;
InputDemandedBits = InputDemandedBits.zext(BitWidth);
KnownZero = KnownZero.zext(BitWidth);
KnownOne = KnownOne.zext(BitWidth);
assert(!(KnownZero & KnownOne) && "Bits known to be one AND zero?");
// If the sign bit of the input is known set or clear, then we know the
// top bits of the result.
// If the input sign bit is known zero, or if the NewBits are not demanded
// convert this into a zero extension.
if (KnownZero[SrcBitWidth-1] || (NewBits & ~DemandedMask) == NewBits) {
// Convert to ZExt cast
CastInst *NewCast = new ZExtInst(I->getOperand(0), VTy, I->getName());
return InsertNewInstWith(NewCast, *I);
} else if (KnownOne[SrcBitWidth-1]) { // Input sign bit known set
KnownOne |= NewBits;
}
break;
}
case Instruction::Add:
case Instruction::Sub: {
/// If the high-bits of an ADD/SUB are not demanded, then we do not care
/// about the high bits of the operands.
unsigned NLZ = DemandedMask.countLeadingZeros();
if (NLZ > 0) {
// Right fill the mask of bits for this ADD/SUB to demand the most
// significant bit and all those below it.
APInt DemandedFromOps(APInt::getLowBitsSet(BitWidth, BitWidth-NLZ));
if (SimplifyDemandedBits(I->getOperandUse(0), DemandedFromOps,
LHSKnownZero, LHSKnownOne, Depth + 1) ||
ShrinkDemandedConstant(I, 1, DemandedFromOps) ||
SimplifyDemandedBits(I->getOperandUse(1), DemandedFromOps,
LHSKnownZero, LHSKnownOne, Depth + 1)) {
// Disable the nsw and nuw flags here: We can no longer guarantee that
// we won't wrap after simplification. Removing the nsw/nuw flags is
// legal here because the top bit is not demanded.
BinaryOperator &BinOP = *cast<BinaryOperator>(I);
BinOP.setHasNoSignedWrap(false);
BinOP.setHasNoUnsignedWrap(false);
return I;
}
}
// Otherwise just hand the add/sub off to computeKnownBits to fill in
// the known zeros and ones.
computeKnownBits(V, KnownZero, KnownOne, Depth, CxtI);
break;
}
case Instruction::Shl:
if (ConstantInt *SA = dyn_cast<ConstantInt>(I->getOperand(1))) {
{
Value *VarX; ConstantInt *C1;
if (match(I->getOperand(0), m_Shr(m_Value(VarX), m_ConstantInt(C1)))) {
Instruction *Shr = cast<Instruction>(I->getOperand(0));
Value *R = SimplifyShrShlDemandedBits(Shr, I, DemandedMask,
KnownZero, KnownOne);
if (R)
return R;
}
}
uint64_t ShiftAmt = SA->getLimitedValue(BitWidth-1);
APInt DemandedMaskIn(DemandedMask.lshr(ShiftAmt));
// If the shift is NUW/NSW, then it does demand the high bits.
ShlOperator *IOp = cast<ShlOperator>(I);
if (IOp->hasNoSignedWrap())
DemandedMaskIn |= APInt::getHighBitsSet(BitWidth, ShiftAmt+1);
else if (IOp->hasNoUnsignedWrap())
DemandedMaskIn |= APInt::getHighBitsSet(BitWidth, ShiftAmt);
if (SimplifyDemandedBits(I->getOperandUse(0), DemandedMaskIn, KnownZero,
KnownOne, Depth + 1))
return I;
assert(!(KnownZero & KnownOne) && "Bits known to be one AND zero?");
KnownZero <<= ShiftAmt;
KnownOne <<= ShiftAmt;
// low bits known zero.
if (ShiftAmt)
KnownZero |= APInt::getLowBitsSet(BitWidth, ShiftAmt);
}
break;
case Instruction::LShr:
// For a logical shift right
if (ConstantInt *SA = dyn_cast<ConstantInt>(I->getOperand(1))) {
uint64_t ShiftAmt = SA->getLimitedValue(BitWidth-1);
// Unsigned shift right.
APInt DemandedMaskIn(DemandedMask.shl(ShiftAmt));
// If the shift is exact, then it does demand the low bits (and knows that
// they are zero).
if (cast<LShrOperator>(I)->isExact())
DemandedMaskIn |= APInt::getLowBitsSet(BitWidth, ShiftAmt);
if (SimplifyDemandedBits(I->getOperandUse(0), DemandedMaskIn, KnownZero,
KnownOne, Depth + 1))
return I;
assert(!(KnownZero & KnownOne) && "Bits known to be one AND zero?");
KnownZero = APIntOps::lshr(KnownZero, ShiftAmt);
KnownOne = APIntOps::lshr(KnownOne, ShiftAmt);
if (ShiftAmt) {
// Compute the new bits that are at the top now.
APInt HighBits(APInt::getHighBitsSet(BitWidth, ShiftAmt));
KnownZero |= HighBits; // high bits known zero.
}
}
break;
case Instruction::AShr:
// If this is an arithmetic shift right and only the low-bit is set, we can
// always convert this into a logical shr, even if the shift amount is
// variable. The low bit of the shift cannot be an input sign bit unless
// the shift amount is >= the size of the datatype, which is undefined.
if (DemandedMask == 1) {
// Perform the logical shift right.
Instruction *NewVal = BinaryOperator::CreateLShr(
I->getOperand(0), I->getOperand(1), I->getName());
return InsertNewInstWith(NewVal, *I);
}
// If the sign bit is the only bit demanded by this ashr, then there is no
// need to do it, the shift doesn't change the high bit.
if (DemandedMask.isSignBit())
return I->getOperand(0);
if (ConstantInt *SA = dyn_cast<ConstantInt>(I->getOperand(1))) {
uint32_t ShiftAmt = SA->getLimitedValue(BitWidth-1);
// Signed shift right.
APInt DemandedMaskIn(DemandedMask.shl(ShiftAmt));
// If any of the "high bits" are demanded, we should set the sign bit as
// demanded.
if (DemandedMask.countLeadingZeros() <= ShiftAmt)
DemandedMaskIn.setBit(BitWidth-1);
// If the shift is exact, then it does demand the low bits (and knows that
// they are zero).
if (cast<AShrOperator>(I)->isExact())
DemandedMaskIn |= APInt::getLowBitsSet(BitWidth, ShiftAmt);
if (SimplifyDemandedBits(I->getOperandUse(0), DemandedMaskIn, KnownZero,
KnownOne, Depth + 1))
return I;
assert(!(KnownZero & KnownOne) && "Bits known to be one AND zero?");
// Compute the new bits that are at the top now.
APInt HighBits(APInt::getHighBitsSet(BitWidth, ShiftAmt));
KnownZero = APIntOps::lshr(KnownZero, ShiftAmt);
KnownOne = APIntOps::lshr(KnownOne, ShiftAmt);
// Handle the sign bits.
APInt SignBit(APInt::getSignBit(BitWidth));
// Adjust to where it is now in the mask.
SignBit = APIntOps::lshr(SignBit, ShiftAmt);
// If the input sign bit is known to be zero, or if none of the top bits
// are demanded, turn this into an unsigned shift right.
if (BitWidth <= ShiftAmt || KnownZero[BitWidth-ShiftAmt-1] ||
(HighBits & ~DemandedMask) == HighBits) {
// Perform the logical shift right.
BinaryOperator *NewVal = BinaryOperator::CreateLShr(I->getOperand(0),
SA, I->getName());
NewVal->setIsExact(cast<BinaryOperator>(I)->isExact());
return InsertNewInstWith(NewVal, *I);
} else if ((KnownOne & SignBit) != 0) { // New bits are known one.
KnownOne |= HighBits;
}
}
break;
case Instruction::SRem:
if (ConstantInt *Rem = dyn_cast<ConstantInt>(I->getOperand(1))) {
// X % -1 demands all the bits because we don't want to introduce
// INT_MIN % -1 (== undef) by accident.
if (Rem->isAllOnesValue())
break;
APInt RA = Rem->getValue().abs();
if (RA.isPowerOf2()) {
if (DemandedMask.ult(RA)) // srem won't affect demanded bits
return I->getOperand(0);
APInt LowBits = RA - 1;
APInt Mask2 = LowBits | APInt::getSignBit(BitWidth);
if (SimplifyDemandedBits(I->getOperandUse(0), Mask2, LHSKnownZero,
LHSKnownOne, Depth + 1))
return I;
// The low bits of LHS are unchanged by the srem.
KnownZero = LHSKnownZero & LowBits;
KnownOne = LHSKnownOne & LowBits;
// If LHS is non-negative or has all low bits zero, then the upper bits
// are all zero.
if (LHSKnownZero[BitWidth-1] || ((LHSKnownZero & LowBits) == LowBits))
KnownZero |= ~LowBits;
// If LHS is negative and not all low bits are zero, then the upper bits
// are all one.
if (LHSKnownOne[BitWidth-1] && ((LHSKnownOne & LowBits) != 0))
KnownOne |= ~LowBits;
assert(!(KnownZero & KnownOne) && "Bits known to be one AND zero?");
}
}
// The sign bit is the LHS's sign bit, except when the result of the
// remainder is zero.
if (DemandedMask.isNegative() && KnownZero.isNonNegative()) {
APInt LHSKnownZero(BitWidth, 0), LHSKnownOne(BitWidth, 0);
computeKnownBits(I->getOperand(0), LHSKnownZero, LHSKnownOne, Depth + 1,
CxtI);
// If it's known zero, our sign bit is also zero.
if (LHSKnownZero.isNegative())
KnownZero.setBit(KnownZero.getBitWidth() - 1);
}
break;
case Instruction::URem: {
APInt KnownZero2(BitWidth, 0), KnownOne2(BitWidth, 0);
APInt AllOnes = APInt::getAllOnesValue(BitWidth);
if (SimplifyDemandedBits(I->getOperandUse(0), AllOnes, KnownZero2,
KnownOne2, Depth + 1) ||
SimplifyDemandedBits(I->getOperandUse(1), AllOnes, KnownZero2,
KnownOne2, Depth + 1))
return I;
unsigned Leaders = KnownZero2.countLeadingOnes();
Leaders = std::max(Leaders,
KnownZero2.countLeadingOnes());
KnownZero = APInt::getHighBitsSet(BitWidth, Leaders) & DemandedMask;
break;
}
case Instruction::Call:
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I)) {
switch (II->getIntrinsicID()) {
default: break;
case Intrinsic::bswap: {
// If the only bits demanded come from one byte of the bswap result,
// just shift the input byte into position to eliminate the bswap.
unsigned NLZ = DemandedMask.countLeadingZeros();
unsigned NTZ = DemandedMask.countTrailingZeros();
// Round NTZ down to the next byte. If we have 11 trailing zeros, then
// we need all the bits down to bit 8. Likewise, round NLZ. If we
// have 14 leading zeros, round to 8.
NLZ &= ~7;
NTZ &= ~7;
// If we need exactly one byte, we can do this transformation.
if (BitWidth-NLZ-NTZ == 8) {
unsigned ResultBit = NTZ;
unsigned InputBit = BitWidth-NTZ-8;
// Replace this with either a left or right shift to get the byte into
// the right place.
Instruction *NewVal;
if (InputBit > ResultBit)
NewVal = BinaryOperator::CreateLShr(II->getArgOperand(0),
ConstantInt::get(I->getType(), InputBit-ResultBit));
else
NewVal = BinaryOperator::CreateShl(II->getArgOperand(0),
ConstantInt::get(I->getType(), ResultBit-InputBit));
NewVal->takeName(I);
return InsertNewInstWith(NewVal, *I);
}
// TODO: Could compute known zero/one bits based on the input.
break;
}
#if 0 // HLSL Change - remove platform intrinsics
case Intrinsic::x86_sse42_crc32_64_64:
KnownZero = APInt::getHighBitsSet(64, 32);
return nullptr;
#endif // HLSL Change - remove platform intrinsics
}
}
computeKnownBits(V, KnownZero, KnownOne, Depth, CxtI);
break;
}
// If the client is only demanding bits that we know, return the known
// constant.
if ((DemandedMask & (KnownZero|KnownOne)) == DemandedMask)
return Constant::getIntegerValue(VTy, KnownOne);
return nullptr;
}
/// Helper routine of SimplifyDemandedUseBits. It tries to simplify
/// "E1 = (X lsr C1) << C2", where the C1 and C2 are constant, into
/// "E2 = X << (C2 - C1)" or "E2 = X >> (C1 - C2)", depending on the sign
/// of "C2-C1".
///
/// Suppose E1 and E2 are generally different in bits S={bm, bm+1,
/// ..., bn}, without considering the specific value X is holding.
/// This transformation is legal iff one of following conditions is hold:
/// 1) All the bit in S are 0, in this case E1 == E2.
/// 2) We don't care those bits in S, per the input DemandedMask.
/// 3) Combination of 1) and 2). Some bits in S are 0, and we don't care the
/// rest bits.
///
/// Currently we only test condition 2).
///
/// As with SimplifyDemandedUseBits, it returns NULL if the simplification was
/// not successful.
Value *InstCombiner::SimplifyShrShlDemandedBits(Instruction *Shr,
Instruction *Shl, APInt DemandedMask, APInt &KnownZero, APInt &KnownOne) {
const APInt &ShlOp1 = cast<ConstantInt>(Shl->getOperand(1))->getValue();
const APInt &ShrOp1 = cast<ConstantInt>(Shr->getOperand(1))->getValue();
if (!ShlOp1 || !ShrOp1)
return nullptr; // Noop.
Value *VarX = Shr->getOperand(0);
Type *Ty = VarX->getType();
unsigned BitWidth = Ty->getIntegerBitWidth();
if (ShlOp1.uge(BitWidth) || ShrOp1.uge(BitWidth))
return nullptr; // Undef.
unsigned ShlAmt = ShlOp1.getZExtValue();
unsigned ShrAmt = ShrOp1.getZExtValue();
KnownOne.clearAllBits();
KnownZero = APInt::getBitsSet(KnownZero.getBitWidth(), 0, ShlAmt-1);
KnownZero &= DemandedMask;
APInt BitMask1(APInt::getAllOnesValue(BitWidth));
APInt BitMask2(APInt::getAllOnesValue(BitWidth));
bool isLshr = (Shr->getOpcode() == Instruction::LShr);
BitMask1 = isLshr ? (BitMask1.lshr(ShrAmt) << ShlAmt) :
(BitMask1.ashr(ShrAmt) << ShlAmt);
if (ShrAmt <= ShlAmt) {
BitMask2 <<= (ShlAmt - ShrAmt);
} else {
BitMask2 = isLshr ? BitMask2.lshr(ShrAmt - ShlAmt):
BitMask2.ashr(ShrAmt - ShlAmt);
}
// Check if condition-2 (see the comment to this function) is satified.
if ((BitMask1 & DemandedMask) == (BitMask2 & DemandedMask)) {
if (ShrAmt == ShlAmt)
return VarX;
if (!Shr->hasOneUse())
return nullptr;
BinaryOperator *New;
if (ShrAmt < ShlAmt) {
Constant *Amt = ConstantInt::get(VarX->getType(), ShlAmt - ShrAmt);
New = BinaryOperator::CreateShl(VarX, Amt);
BinaryOperator *Orig = cast<BinaryOperator>(Shl);
New->setHasNoSignedWrap(Orig->hasNoSignedWrap());
New->setHasNoUnsignedWrap(Orig->hasNoUnsignedWrap());
} else {
Constant *Amt = ConstantInt::get(VarX->getType(), ShrAmt - ShlAmt);
New = isLshr ? BinaryOperator::CreateLShr(VarX, Amt) :
BinaryOperator::CreateAShr(VarX, Amt);
if (cast<BinaryOperator>(Shr)->isExact())
New->setIsExact(true);
}
return InsertNewInstWith(New, *Shl);
}
return nullptr;
}
/// SimplifyDemandedVectorElts - The specified value produces a vector with
/// any number of elements. DemandedElts contains the set of elements that are
/// actually used by the caller. This method analyzes which elements of the
/// operand are undef and returns that information in UndefElts.
///
/// If the information about demanded elements can be used to simplify the
/// operation, the operation is simplified, then the resultant value is
/// returned. This returns null if no change was made.
Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
APInt &UndefElts,
unsigned Depth) {
unsigned VWidth = cast<VectorType>(V->getType())->getNumElements();
APInt EltMask(APInt::getAllOnesValue(VWidth));
assert((DemandedElts & ~EltMask) == 0 && "Invalid DemandedElts!");
if (isa<UndefValue>(V)) {
// If the entire vector is undefined, just return this info.
UndefElts = EltMask;
return nullptr;
}
if (DemandedElts == 0) { // If nothing is demanded, provide undef.
UndefElts = EltMask;
return UndefValue::get(V->getType());
}
UndefElts = 0;
// Handle ConstantAggregateZero, ConstantVector, ConstantDataSequential.
if (Constant *C = dyn_cast<Constant>(V)) {
// Check if this is identity. If so, return 0 since we are not simplifying
// anything.
if (DemandedElts.isAllOnesValue())
return nullptr;
Type *EltTy = cast<VectorType>(V->getType())->getElementType();
Constant *Undef = UndefValue::get(EltTy);
SmallVector<Constant*, 16> Elts;
for (unsigned i = 0; i != VWidth; ++i) {
if (!DemandedElts[i]) { // If not demanded, set to undef.
Elts.push_back(Undef);
UndefElts.setBit(i);
continue;
}
Constant *Elt = C->getAggregateElement(i);
if (!Elt) return nullptr;
if (isa<UndefValue>(Elt)) { // Already undef.
Elts.push_back(Undef);
UndefElts.setBit(i);
} else { // Otherwise, defined.
Elts.push_back(Elt);
}
}
// If we changed the constant, return it.
Constant *NewCV = ConstantVector::get(Elts);
return NewCV != C ? NewCV : nullptr;
}
// Limit search depth.
if (Depth == 10)
return nullptr;
// If multiple users are using the root value, proceed with
// simplification conservatively assuming that all elements
// are needed.
if (!V->hasOneUse()) {
// Quit if we find multiple users of a non-root value though.
// They'll be handled when it's their turn to be visited by
// the main instcombine process.
if (Depth != 0)
// TODO: Just compute the UndefElts information recursively.
return nullptr;
// Conservatively assume that all elements are needed.
DemandedElts = EltMask;
}
Instruction *I = dyn_cast<Instruction>(V);
if (!I) return nullptr; // Only analyze instructions.
bool MadeChange = false;
APInt UndefElts2(VWidth, 0);
Value *TmpV;
switch (I->getOpcode()) {
default: break;
case Instruction::InsertElement: {
// If this is a variable index, we don't know which element it overwrites.
// demand exactly the same input as we produce.
ConstantInt *Idx = dyn_cast<ConstantInt>(I->getOperand(2));
if (!Idx) {
// Note that we can't propagate undef elt info, because we don't know
// which elt is getting updated.
TmpV = SimplifyDemandedVectorElts(I->getOperand(0), DemandedElts,
UndefElts2, Depth + 1);
if (TmpV) { I->setOperand(0, TmpV); MadeChange = true; }
break;
}
// If this is inserting an element that isn't demanded, remove this
// insertelement.
unsigned IdxNo = Idx->getZExtValue();
if (IdxNo >= VWidth || !DemandedElts[IdxNo]) {
Worklist.Add(I);
return I->getOperand(0);
}
// Otherwise, the element inserted overwrites whatever was there, so the
// input demanded set is simpler than the output set.
APInt DemandedElts2 = DemandedElts;
DemandedElts2.clearBit(IdxNo);
TmpV = SimplifyDemandedVectorElts(I->getOperand(0), DemandedElts2,
UndefElts, Depth + 1);
if (TmpV) { I->setOperand(0, TmpV); MadeChange = true; }
// The inserted element is defined.
UndefElts.clearBit(IdxNo);
break;
}
case Instruction::ShuffleVector: {
ShuffleVectorInst *Shuffle = cast<ShuffleVectorInst>(I);
uint64_t LHSVWidth =
cast<VectorType>(Shuffle->getOperand(0)->getType())->getNumElements();
APInt LeftDemanded(LHSVWidth, 0), RightDemanded(LHSVWidth, 0);
for (unsigned i = 0; i < VWidth; i++) {
if (DemandedElts[i]) {
unsigned MaskVal = Shuffle->getMaskValue(i);
if (MaskVal != -1u) {
assert(MaskVal < LHSVWidth * 2 &&
"shufflevector mask index out of range!");
if (MaskVal < LHSVWidth)
LeftDemanded.setBit(MaskVal);
else
RightDemanded.setBit(MaskVal - LHSVWidth);
}
}
}
APInt UndefElts4(LHSVWidth, 0);
TmpV = SimplifyDemandedVectorElts(I->getOperand(0), LeftDemanded,
UndefElts4, Depth + 1);
if (TmpV) { I->setOperand(0, TmpV); MadeChange = true; }
APInt UndefElts3(LHSVWidth, 0);
TmpV = SimplifyDemandedVectorElts(I->getOperand(1), RightDemanded,
UndefElts3, Depth + 1);
if (TmpV) { I->setOperand(1, TmpV); MadeChange = true; }
bool NewUndefElts = false;
for (unsigned i = 0; i < VWidth; i++) {
unsigned MaskVal = Shuffle->getMaskValue(i);
if (MaskVal == -1u) {
UndefElts.setBit(i);
} else if (!DemandedElts[i]) {
NewUndefElts = true;
UndefElts.setBit(i);
} else if (MaskVal < LHSVWidth) {
if (UndefElts4[MaskVal]) {
NewUndefElts = true;
UndefElts.setBit(i);
}
} else {
if (UndefElts3[MaskVal - LHSVWidth]) {
NewUndefElts = true;
UndefElts.setBit(i);
}
}
}
if (NewUndefElts) {
// Add additional discovered undefs.
SmallVector<Constant*, 16> Elts;
for (unsigned i = 0; i < VWidth; ++i) {
if (UndefElts[i])
Elts.push_back(UndefValue::get(Type::getInt32Ty(I->getContext())));
else
Elts.push_back(ConstantInt::get(Type::getInt32Ty(I->getContext()),
Shuffle->getMaskValue(i)));
}
I->setOperand(2, ConstantVector::get(Elts));
MadeChange = true;
}
break;
}
case Instruction::Select: {
APInt LeftDemanded(DemandedElts), RightDemanded(DemandedElts);
if (ConstantVector* CV = dyn_cast<ConstantVector>(I->getOperand(0))) {
for (unsigned i = 0; i < VWidth; i++) {
if (CV->getAggregateElement(i)->isNullValue())
LeftDemanded.clearBit(i);
else
RightDemanded.clearBit(i);
}
}
TmpV = SimplifyDemandedVectorElts(I->getOperand(1), LeftDemanded, UndefElts,
Depth + 1);
if (TmpV) { I->setOperand(1, TmpV); MadeChange = true; }
TmpV = SimplifyDemandedVectorElts(I->getOperand(2), RightDemanded,
UndefElts2, Depth + 1);
if (TmpV) { I->setOperand(2, TmpV); MadeChange = true; }
// Output elements are undefined if both are undefined.
UndefElts &= UndefElts2;
break;
}
case Instruction::BitCast: {
// Vector->vector casts only.
VectorType *VTy = dyn_cast<VectorType>(I->getOperand(0)->getType());
if (!VTy) break;
unsigned InVWidth = VTy->getNumElements();
APInt InputDemandedElts(InVWidth, 0);
unsigned Ratio;
if (VWidth == InVWidth) {
// If we are converting from <4 x i32> -> <4 x f32>, we demand the same
// elements as are demanded of us.
Ratio = 1;
InputDemandedElts = DemandedElts;
} else if (VWidth > InVWidth) {
// Untested so far.
break;
// If there are more elements in the result than there are in the source,
// then an input element is live if any of the corresponding output
// elements are live.
Ratio = VWidth/InVWidth;
for (unsigned OutIdx = 0; OutIdx != VWidth; ++OutIdx) {
if (DemandedElts[OutIdx])
InputDemandedElts.setBit(OutIdx/Ratio);
}
} else {
// Untested so far.
break;
// If there are more elements in the source than there are in the result,
// then an input element is live if the corresponding output element is
// live.
Ratio = InVWidth/VWidth;
for (unsigned InIdx = 0; InIdx != InVWidth; ++InIdx)
if (DemandedElts[InIdx/Ratio])
InputDemandedElts.setBit(InIdx);
}
// div/rem demand all inputs, because they don't want divide by zero.
TmpV = SimplifyDemandedVectorElts(I->getOperand(0), InputDemandedElts,
UndefElts2, Depth + 1);
if (TmpV) {
I->setOperand(0, TmpV);
MadeChange = true;
}
UndefElts = UndefElts2;
if (VWidth > InVWidth) {
llvm_unreachable("Unimp");
// If there are more elements in the result than there are in the source,
// then an output element is undef if the corresponding input element is
// undef.
for (unsigned OutIdx = 0; OutIdx != VWidth; ++OutIdx)
if (UndefElts2[OutIdx/Ratio])
UndefElts.setBit(OutIdx);
} else if (VWidth < InVWidth) {
llvm_unreachable("Unimp");
// If there are more elements in the source than there are in the result,
// then a result element is undef if all of the corresponding input
// elements are undef.
UndefElts = ~0ULL >> (64-VWidth); // Start out all undef.
for (unsigned InIdx = 0; InIdx != InVWidth; ++InIdx)
if (!UndefElts2[InIdx]) // Not undef?
UndefElts.clearBit(InIdx/Ratio); // Clear undef bit.
}
break;
}
case Instruction::And:
case Instruction::Or:
case Instruction::Xor:
case Instruction::Add:
case Instruction::Sub:
case Instruction::Mul:
// div/rem demand all inputs, because they don't want divide by zero.
TmpV = SimplifyDemandedVectorElts(I->getOperand(0), DemandedElts, UndefElts,
Depth + 1);
if (TmpV) { I->setOperand(0, TmpV); MadeChange = true; }
TmpV = SimplifyDemandedVectorElts(I->getOperand(1), DemandedElts,
UndefElts2, Depth + 1);
if (TmpV) { I->setOperand(1, TmpV); MadeChange = true; }
// Output elements are undefined if both are undefined. Consider things
// like undef&0. The result is known zero, not undef.
UndefElts &= UndefElts2;
break;
case Instruction::FPTrunc:
case Instruction::FPExt:
TmpV = SimplifyDemandedVectorElts(I->getOperand(0), DemandedElts, UndefElts,
Depth + 1);
if (TmpV) { I->setOperand(0, TmpV); MadeChange = true; }
break;
case Instruction::Call: {
IntrinsicInst *II = dyn_cast<IntrinsicInst>(I);
if (!II) break;
#if 0 // HLSL Change - remove platform intrinsics
switch (II->getIntrinsicID()) {
default: break;
// Binary vector operations that work column-wise. A dest element is a
// function of the corresponding input elements from the two inputs.
case Intrinsic::x86_sse_sub_ss:
case Intrinsic::x86_sse_mul_ss:
case Intrinsic::x86_sse_min_ss:
case Intrinsic::x86_sse_max_ss:
case Intrinsic::x86_sse2_sub_sd:
case Intrinsic::x86_sse2_mul_sd:
case Intrinsic::x86_sse2_min_sd:
case Intrinsic::x86_sse2_max_sd:
TmpV = SimplifyDemandedVectorElts(II->getArgOperand(0), DemandedElts,
UndefElts, Depth + 1);
if (TmpV) { II->setArgOperand(0, TmpV); MadeChange = true; }
TmpV = SimplifyDemandedVectorElts(II->getArgOperand(1), DemandedElts,
UndefElts2, Depth + 1);
if (TmpV) { II->setArgOperand(1, TmpV); MadeChange = true; }
// If only the low elt is demanded and this is a scalarizable intrinsic,
// scalarize it now.
if (DemandedElts == 1) {
switch (II->getIntrinsicID()) {
default: break;
case Intrinsic::x86_sse_sub_ss:
case Intrinsic::x86_sse_mul_ss:
case Intrinsic::x86_sse2_sub_sd:
case Intrinsic::x86_sse2_mul_sd:
// TODO: Lower MIN/MAX/ABS/etc
Value *LHS = II->getArgOperand(0);
Value *RHS = II->getArgOperand(1);
// Extract the element as scalars.
LHS = InsertNewInstWith(ExtractElementInst::Create(LHS,
ConstantInt::get(Type::getInt32Ty(I->getContext()), 0U)), *II);
RHS = InsertNewInstWith(ExtractElementInst::Create(RHS,
ConstantInt::get(Type::getInt32Ty(I->getContext()), 0U)), *II);
switch (II->getIntrinsicID()) {
default: llvm_unreachable("Case stmts out of sync!");
case Intrinsic::x86_sse_sub_ss:
case Intrinsic::x86_sse2_sub_sd:
TmpV = InsertNewInstWith(BinaryOperator::CreateFSub(LHS, RHS,
II->getName()), *II);
break;
case Intrinsic::x86_sse_mul_ss:
case Intrinsic::x86_sse2_mul_sd:
TmpV = InsertNewInstWith(BinaryOperator::CreateFMul(LHS, RHS,
II->getName()), *II);
break;
}
Instruction *New =
InsertElementInst::Create(
UndefValue::get(II->getType()), TmpV,
ConstantInt::get(Type::getInt32Ty(I->getContext()), 0U, false),
II->getName());
InsertNewInstWith(New, *II);
return New;
}
}
// Output elements are undefined if both are undefined. Consider things
// like undef&0. The result is known zero, not undef.
UndefElts &= UndefElts2;
break;
}
#endif // HLSL Change - remove platform intrinsics
break;
}
}
return MadeChange ? I : nullptr;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/InstCombine/InstCombineShifts.cpp | //===- InstCombineShifts.cpp ----------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the visitShl, visitLShr, and visitAShr functions.
//
//===----------------------------------------------------------------------===//
#include "InstCombineInternal.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/PatternMatch.h"
using namespace llvm;
using namespace PatternMatch;
#define DEBUG_TYPE "instcombine"
Instruction *InstCombiner::commonShiftTransforms(BinaryOperator &I) {
assert(I.getOperand(1)->getType() == I.getOperand(0)->getType());
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
// See if we can fold away this shift.
if (SimplifyDemandedInstructionBits(I))
return &I;
// Try to fold constant and into select arguments.
if (isa<Constant>(Op0))
if (SelectInst *SI = dyn_cast<SelectInst>(Op1))
if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (Constant *CUI = dyn_cast<Constant>(Op1))
if (Instruction *Res = FoldShiftByConstant(Op0, CUI, I))
return Res;
// X shift (A srem B) -> X shift (A and B-1) iff B is a power of 2.
// Because shifts by negative values (which could occur if A were negative)
// are undefined.
Value *A; const APInt *B;
if (Op1->hasOneUse() && match(Op1, m_SRem(m_Value(A), m_Power2(B)))) {
// FIXME: Should this get moved into SimplifyDemandedBits by saying we don't
// demand the sign bit (and many others) here??
Value *Rem = Builder->CreateAnd(A, ConstantInt::get(I.getType(), *B-1),
Op1->getName());
I.setOperand(1, Rem);
return &I;
}
return nullptr;
}
/// CanEvaluateShifted - See if we can compute the specified value, but shifted
/// logically to the left or right by some number of bits. This should return
/// true if the expression can be computed for the same cost as the current
/// expression tree. This is used to eliminate extraneous shifting from things
/// like:
/// %C = shl i128 %A, 64
/// %D = shl i128 %B, 96
/// %E = or i128 %C, %D
/// %F = lshr i128 %E, 64
/// where the client will ask if E can be computed shifted right by 64-bits. If
/// this succeeds, the GetShiftedValue function will be called to produce the
/// value.
static bool CanEvaluateShifted(Value *V, unsigned NumBits, bool isLeftShift,
InstCombiner &IC, Instruction *CxtI) {
// We can always evaluate constants shifted.
if (isa<Constant>(V))
return true;
Instruction *I = dyn_cast<Instruction>(V);
if (!I) return false;
// If this is the opposite shift, we can directly reuse the input of the shift
// if the needed bits are already zero in the input. This allows us to reuse
// the value which means that we don't care if the shift has multiple uses.
// TODO: Handle opposite shift by exact value.
ConstantInt *CI = nullptr;
if ((isLeftShift && match(I, m_LShr(m_Value(), m_ConstantInt(CI)))) ||
(!isLeftShift && match(I, m_Shl(m_Value(), m_ConstantInt(CI))))) {
if (CI->getZExtValue() == NumBits) {
// TODO: Check that the input bits are already zero with MaskedValueIsZero
#if 0
// If this is a truncate of a logical shr, we can truncate it to a smaller
// lshr iff we know that the bits we would otherwise be shifting in are
// already zeros.
uint32_t OrigBitWidth = OrigTy->getScalarSizeInBits();
uint32_t BitWidth = Ty->getScalarSizeInBits();
if (MaskedValueIsZero(I->getOperand(0),
APInt::getHighBitsSet(OrigBitWidth, OrigBitWidth-BitWidth)) &&
CI->getLimitedValue(BitWidth) < BitWidth) {
return CanEvaluateTruncated(I->getOperand(0), Ty);
}
#endif
}
}
// We can't mutate something that has multiple uses: doing so would
// require duplicating the instruction in general, which isn't profitable.
if (!I->hasOneUse()) return false;
switch (I->getOpcode()) {
default: return false;
case Instruction::And:
case Instruction::Or:
case Instruction::Xor:
// Bitwise operators can all arbitrarily be arbitrarily evaluated shifted.
return CanEvaluateShifted(I->getOperand(0), NumBits, isLeftShift, IC, I) &&
CanEvaluateShifted(I->getOperand(1), NumBits, isLeftShift, IC, I);
case Instruction::Shl: {
// We can often fold the shift into shifts-by-a-constant.
CI = dyn_cast<ConstantInt>(I->getOperand(1));
if (!CI) return false;
// We can always fold shl(c1)+shl(c2) -> shl(c1+c2).
if (isLeftShift) return true;
// We can always turn shl(c)+shr(c) -> and(c2).
if (CI->getValue() == NumBits) return true;
unsigned TypeWidth = I->getType()->getScalarSizeInBits();
// We can turn shl(c1)+shr(c2) -> shl(c3)+and(c4), but it isn't
// profitable unless we know the and'd out bits are already zero.
if (CI->getZExtValue() > NumBits) {
unsigned LowBits = TypeWidth - CI->getZExtValue();
if (IC.MaskedValueIsZero(I->getOperand(0),
APInt::getLowBitsSet(TypeWidth, NumBits) << LowBits,
0, CxtI))
return true;
}
return false;
}
case Instruction::LShr: {
// We can often fold the shift into shifts-by-a-constant.
CI = dyn_cast<ConstantInt>(I->getOperand(1));
if (!CI) return false;
// We can always fold lshr(c1)+lshr(c2) -> lshr(c1+c2).
if (!isLeftShift) return true;
// We can always turn lshr(c)+shl(c) -> and(c2).
if (CI->getValue() == NumBits) return true;
unsigned TypeWidth = I->getType()->getScalarSizeInBits();
// We can always turn lshr(c1)+shl(c2) -> lshr(c3)+and(c4), but it isn't
// profitable unless we know the and'd out bits are already zero.
if (CI->getValue().ult(TypeWidth) && CI->getZExtValue() > NumBits) {
unsigned LowBits = CI->getZExtValue() - NumBits;
if (IC.MaskedValueIsZero(I->getOperand(0),
APInt::getLowBitsSet(TypeWidth, NumBits) << LowBits,
0, CxtI))
return true;
}
return false;
}
case Instruction::Select: {
SelectInst *SI = cast<SelectInst>(I);
return CanEvaluateShifted(SI->getTrueValue(), NumBits, isLeftShift,
IC, SI) &&
CanEvaluateShifted(SI->getFalseValue(), NumBits, isLeftShift, IC, SI);
}
case Instruction::PHI: {
// We can change a phi if we can change all operands. Note that we never
// get into trouble with cyclic PHIs here because we only consider
// instructions with a single use.
PHINode *PN = cast<PHINode>(I);
for (Value *IncValue : PN->incoming_values())
if (!CanEvaluateShifted(IncValue, NumBits, isLeftShift,
IC, PN))
return false;
return true;
}
}
}
/// GetShiftedValue - When CanEvaluateShifted returned true for an expression,
/// this value inserts the new computation that produces the shifted value.
static Value *GetShiftedValue(Value *V, unsigned NumBits, bool isLeftShift,
InstCombiner &IC, const DataLayout &DL) {
// We can always evaluate constants shifted.
if (Constant *C = dyn_cast<Constant>(V)) {
if (isLeftShift)
V = IC.Builder->CreateShl(C, NumBits);
else
V = IC.Builder->CreateLShr(C, NumBits);
// If we got a constantexpr back, try to simplify it with TD info.
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
V = ConstantFoldConstantExpression(CE, DL, IC.getTargetLibraryInfo());
return V;
}
Instruction *I = cast<Instruction>(V);
IC.Worklist.Add(I);
switch (I->getOpcode()) {
default: llvm_unreachable("Inconsistency with CanEvaluateShifted");
case Instruction::And:
case Instruction::Or:
case Instruction::Xor:
// Bitwise operators can all arbitrarily be arbitrarily evaluated shifted.
I->setOperand(
0, GetShiftedValue(I->getOperand(0), NumBits, isLeftShift, IC, DL));
I->setOperand(
1, GetShiftedValue(I->getOperand(1), NumBits, isLeftShift, IC, DL));
return I;
case Instruction::Shl: {
BinaryOperator *BO = cast<BinaryOperator>(I);
unsigned TypeWidth = BO->getType()->getScalarSizeInBits();
// We only accept shifts-by-a-constant in CanEvaluateShifted.
ConstantInt *CI = cast<ConstantInt>(BO->getOperand(1));
// We can always fold shl(c1)+shl(c2) -> shl(c1+c2).
if (isLeftShift) {
// If this is oversized composite shift, then unsigned shifts get 0.
unsigned NewShAmt = NumBits+CI->getZExtValue();
if (NewShAmt >= TypeWidth)
return Constant::getNullValue(I->getType());
BO->setOperand(1, ConstantInt::get(BO->getType(), NewShAmt));
BO->setHasNoUnsignedWrap(false);
BO->setHasNoSignedWrap(false);
return I;
}
// We turn shl(c)+lshr(c) -> and(c2) if the input doesn't already have
// zeros.
if (CI->getValue() == NumBits) {
APInt Mask(APInt::getLowBitsSet(TypeWidth, TypeWidth - NumBits));
V = IC.Builder->CreateAnd(BO->getOperand(0),
ConstantInt::get(BO->getContext(), Mask));
if (Instruction *VI = dyn_cast<Instruction>(V)) {
VI->moveBefore(BO);
VI->takeName(BO);
}
return V;
}
// We turn shl(c1)+shr(c2) -> shl(c3)+and(c4), but only when we know that
// the and won't be needed.
assert(CI->getZExtValue() > NumBits);
BO->setOperand(1, ConstantInt::get(BO->getType(),
CI->getZExtValue() - NumBits));
BO->setHasNoUnsignedWrap(false);
BO->setHasNoSignedWrap(false);
return BO;
}
case Instruction::LShr: {
BinaryOperator *BO = cast<BinaryOperator>(I);
unsigned TypeWidth = BO->getType()->getScalarSizeInBits();
// We only accept shifts-by-a-constant in CanEvaluateShifted.
ConstantInt *CI = cast<ConstantInt>(BO->getOperand(1));
// We can always fold lshr(c1)+lshr(c2) -> lshr(c1+c2).
if (!isLeftShift) {
// If this is oversized composite shift, then unsigned shifts get 0.
unsigned NewShAmt = NumBits+CI->getZExtValue();
if (NewShAmt >= TypeWidth)
return Constant::getNullValue(BO->getType());
BO->setOperand(1, ConstantInt::get(BO->getType(), NewShAmt));
BO->setIsExact(false);
return I;
}
// We turn lshr(c)+shl(c) -> and(c2) if the input doesn't already have
// zeros.
if (CI->getValue() == NumBits) {
APInt Mask(APInt::getHighBitsSet(TypeWidth, TypeWidth - NumBits));
V = IC.Builder->CreateAnd(I->getOperand(0),
ConstantInt::get(BO->getContext(), Mask));
if (Instruction *VI = dyn_cast<Instruction>(V)) {
VI->moveBefore(I);
VI->takeName(I);
}
return V;
}
// We turn lshr(c1)+shl(c2) -> lshr(c3)+and(c4), but only when we know that
// the and won't be needed.
assert(CI->getZExtValue() > NumBits);
BO->setOperand(1, ConstantInt::get(BO->getType(),
CI->getZExtValue() - NumBits));
BO->setIsExact(false);
return BO;
}
case Instruction::Select:
I->setOperand(
1, GetShiftedValue(I->getOperand(1), NumBits, isLeftShift, IC, DL));
I->setOperand(
2, GetShiftedValue(I->getOperand(2), NumBits, isLeftShift, IC, DL));
return I;
case Instruction::PHI: {
// We can change a phi if we can change all operands. Note that we never
// get into trouble with cyclic PHIs here because we only consider
// instructions with a single use.
PHINode *PN = cast<PHINode>(I);
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
PN->setIncomingValue(i, GetShiftedValue(PN->getIncomingValue(i), NumBits,
isLeftShift, IC, DL));
return PN;
}
}
}
Instruction *InstCombiner::FoldShiftByConstant(Value *Op0, Constant *Op1,
BinaryOperator &I) {
bool isLeftShift = I.getOpcode() == Instruction::Shl;
ConstantInt *COp1 = nullptr;
if (ConstantDataVector *CV = dyn_cast<ConstantDataVector>(Op1))
COp1 = dyn_cast_or_null<ConstantInt>(CV->getSplatValue());
else if (ConstantVector *CV = dyn_cast<ConstantVector>(Op1))
COp1 = dyn_cast_or_null<ConstantInt>(CV->getSplatValue());
else
COp1 = dyn_cast<ConstantInt>(Op1);
if (!COp1)
return nullptr;
// See if we can propagate this shift into the input, this covers the trivial
// cast of lshr(shl(x,c1),c2) as well as other more complex cases.
if (I.getOpcode() != Instruction::AShr &&
CanEvaluateShifted(Op0, COp1->getZExtValue(), isLeftShift, *this, &I)) {
DEBUG(dbgs() << "ICE: GetShiftedValue propagating shift through expression"
" to eliminate shift:\n IN: " << *Op0 << "\n SH: " << I <<"\n");
return ReplaceInstUsesWith(
I, GetShiftedValue(Op0, COp1->getZExtValue(), isLeftShift, *this, DL));
}
// See if we can simplify any instructions used by the instruction whose sole
// purpose is to compute bits we don't care about.
uint32_t TypeBits = Op0->getType()->getScalarSizeInBits();
assert(!COp1->uge(TypeBits) &&
"Shift over the type width should have been removed already");
// ((X*C1) << C2) == (X * (C1 << C2))
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(Op0))
if (BO->getOpcode() == Instruction::Mul && isLeftShift)
if (Constant *BOOp = dyn_cast<Constant>(BO->getOperand(1)))
return BinaryOperator::CreateMul(BO->getOperand(0),
ConstantExpr::getShl(BOOp, Op1));
// Try to fold constant and into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (isa<PHINode>(Op0))
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
// Fold shift2(trunc(shift1(x,c1)), c2) -> trunc(shift2(shift1(x,c1),c2))
if (TruncInst *TI = dyn_cast<TruncInst>(Op0)) {
Instruction *TrOp = dyn_cast<Instruction>(TI->getOperand(0));
// If 'shift2' is an ashr, we would have to get the sign bit into a funny
// place. Don't try to do this transformation in this case. Also, we
// require that the input operand is a shift-by-constant so that we have
// confidence that the shifts will get folded together. We could do this
// xform in more cases, but it is unlikely to be profitable.
if (TrOp && I.isLogicalShift() && TrOp->isShift() &&
isa<ConstantInt>(TrOp->getOperand(1))) {
// Okay, we'll do this xform. Make the shift of shift.
Constant *ShAmt = ConstantExpr::getZExt(COp1, TrOp->getType());
// (shift2 (shift1 & 0x00FF), c2)
Value *NSh = Builder->CreateBinOp(I.getOpcode(), TrOp, ShAmt,I.getName());
// For logical shifts, the truncation has the effect of making the high
// part of the register be zeros. Emulate this by inserting an AND to
// clear the top bits as needed. This 'and' will usually be zapped by
// other xforms later if dead.
unsigned SrcSize = TrOp->getType()->getScalarSizeInBits();
unsigned DstSize = TI->getType()->getScalarSizeInBits();
APInt MaskV(APInt::getLowBitsSet(SrcSize, DstSize));
// The mask we constructed says what the trunc would do if occurring
// between the shifts. We want to know the effect *after* the second
// shift. We know that it is a logical shift by a constant, so adjust the
// mask as appropriate.
if (I.getOpcode() == Instruction::Shl)
MaskV <<= COp1->getZExtValue();
else {
assert(I.getOpcode() == Instruction::LShr && "Unknown logical shift");
MaskV = MaskV.lshr(COp1->getZExtValue());
}
// shift1 & 0x00FF
Value *And = Builder->CreateAnd(NSh,
ConstantInt::get(I.getContext(), MaskV),
TI->getName());
// Return the value truncated to the interesting size.
return new TruncInst(And, I.getType());
}
}
if (Op0->hasOneUse()) {
if (BinaryOperator *Op0BO = dyn_cast<BinaryOperator>(Op0)) {
// Turn ((X >> C) + Y) << C -> (X + (Y << C)) & (~0 << C)
Value *V1, *V2;
ConstantInt *CC;
switch (Op0BO->getOpcode()) {
default: break;
case Instruction::Add:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor: {
// These operators commute.
// Turn (Y + (X >> C)) << C -> (X + (Y << C)) & (~0 << C)
if (isLeftShift && Op0BO->getOperand(1)->hasOneUse() &&
match(Op0BO->getOperand(1), m_Shr(m_Value(V1),
m_Specific(Op1)))) {
Value *YS = // (Y << C)
Builder->CreateShl(Op0BO->getOperand(0), Op1, Op0BO->getName());
// (X + (Y << C))
Value *X = Builder->CreateBinOp(Op0BO->getOpcode(), YS, V1,
Op0BO->getOperand(1)->getName());
uint32_t Op1Val = COp1->getLimitedValue(TypeBits);
APInt Bits = APInt::getHighBitsSet(TypeBits, TypeBits - Op1Val);
Constant *Mask = ConstantInt::get(I.getContext(), Bits);
if (VectorType *VT = dyn_cast<VectorType>(X->getType()))
Mask = ConstantVector::getSplat(VT->getNumElements(), Mask);
return BinaryOperator::CreateAnd(X, Mask);
}
// Turn (Y + ((X >> C) & CC)) << C -> ((X & (CC << C)) + (Y << C))
Value *Op0BOOp1 = Op0BO->getOperand(1);
if (isLeftShift && Op0BOOp1->hasOneUse() &&
match(Op0BOOp1,
m_And(m_OneUse(m_Shr(m_Value(V1), m_Specific(Op1))),
m_ConstantInt(CC)))) {
Value *YS = // (Y << C)
Builder->CreateShl(Op0BO->getOperand(0), Op1,
Op0BO->getName());
// X & (CC << C)
Value *XM = Builder->CreateAnd(V1, ConstantExpr::getShl(CC, Op1),
V1->getName()+".mask");
return BinaryOperator::Create(Op0BO->getOpcode(), YS, XM);
}
}
LLVM_FALLTHROUGH; // HLSL CHANGE
case Instruction::Sub: {
// Turn ((X >> C) + Y) << C -> (X + (Y << C)) & (~0 << C)
if (isLeftShift && Op0BO->getOperand(0)->hasOneUse() &&
match(Op0BO->getOperand(0), m_Shr(m_Value(V1),
m_Specific(Op1)))) {
Value *YS = // (Y << C)
Builder->CreateShl(Op0BO->getOperand(1), Op1, Op0BO->getName());
// (X + (Y << C))
Value *X = Builder->CreateBinOp(Op0BO->getOpcode(), V1, YS,
Op0BO->getOperand(0)->getName());
uint32_t Op1Val = COp1->getLimitedValue(TypeBits);
APInt Bits = APInt::getHighBitsSet(TypeBits, TypeBits - Op1Val);
Constant *Mask = ConstantInt::get(I.getContext(), Bits);
if (VectorType *VT = dyn_cast<VectorType>(X->getType()))
Mask = ConstantVector::getSplat(VT->getNumElements(), Mask);
return BinaryOperator::CreateAnd(X, Mask);
}
// Turn (((X >> C)&CC) + Y) << C -> (X + (Y << C)) & (CC << C)
if (isLeftShift && Op0BO->getOperand(0)->hasOneUse() &&
match(Op0BO->getOperand(0),
m_And(m_OneUse(m_Shr(m_Value(V1), m_Value(V2))),
m_ConstantInt(CC))) && V2 == Op1) {
Value *YS = // (Y << C)
Builder->CreateShl(Op0BO->getOperand(1), Op1, Op0BO->getName());
// X & (CC << C)
Value *XM = Builder->CreateAnd(V1, ConstantExpr::getShl(CC, Op1),
V1->getName()+".mask");
return BinaryOperator::Create(Op0BO->getOpcode(), XM, YS);
}
break;
}
}
// If the operand is a bitwise operator with a constant RHS, and the
// shift is the only use, we can pull it out of the shift.
if (ConstantInt *Op0C = dyn_cast<ConstantInt>(Op0BO->getOperand(1))) {
bool isValid = true; // Valid only for And, Or, Xor
bool highBitSet = false; // Transform if high bit of constant set?
switch (Op0BO->getOpcode()) {
default: isValid = false; break; // Do not perform transform!
case Instruction::Add:
isValid = isLeftShift;
break;
case Instruction::Or:
case Instruction::Xor:
highBitSet = false;
break;
case Instruction::And:
highBitSet = true;
break;
}
// If this is a signed shift right, and the high bit is modified
// by the logical operation, do not perform the transformation.
// The highBitSet boolean indicates the value of the high bit of
// the constant which would cause it to be modified for this
// operation.
//
if (isValid && I.getOpcode() == Instruction::AShr)
isValid = Op0C->getValue()[TypeBits-1] == highBitSet;
if (isValid) {
Constant *NewRHS = ConstantExpr::get(I.getOpcode(), Op0C, Op1);
Value *NewShift =
Builder->CreateBinOp(I.getOpcode(), Op0BO->getOperand(0), Op1);
NewShift->takeName(Op0BO);
return BinaryOperator::Create(Op0BO->getOpcode(), NewShift,
NewRHS);
}
}
}
}
// Find out if this is a shift of a shift by a constant.
BinaryOperator *ShiftOp = dyn_cast<BinaryOperator>(Op0);
if (ShiftOp && !ShiftOp->isShift())
ShiftOp = nullptr;
if (ShiftOp && isa<ConstantInt>(ShiftOp->getOperand(1))) {
// This is a constant shift of a constant shift. Be careful about hiding
// shl instructions behind bit masks. They are used to represent multiplies
// by a constant, and it is important that simple arithmetic expressions
// are still recognizable by scalar evolution.
//
// The transforms applied to shl are very similar to the transforms applied
// to mul by constant. We can be more aggressive about optimizing right
// shifts.
//
// Combinations of right and left shifts will still be optimized in
// DAGCombine where scalar evolution no longer applies.
ConstantInt *ShiftAmt1C = cast<ConstantInt>(ShiftOp->getOperand(1));
uint32_t ShiftAmt1 = ShiftAmt1C->getLimitedValue(TypeBits);
uint32_t ShiftAmt2 = COp1->getLimitedValue(TypeBits);
assert(ShiftAmt2 != 0 && "Should have been simplified earlier");
if (ShiftAmt1 == 0) return nullptr; // Will be simplified in the future.
Value *X = ShiftOp->getOperand(0);
IntegerType *Ty = cast<IntegerType>(I.getType());
// Check for (X << c1) << c2 and (X >> c1) >> c2
if (I.getOpcode() == ShiftOp->getOpcode()) {
uint32_t AmtSum = ShiftAmt1+ShiftAmt2; // Fold into one big shift.
// If this is oversized composite shift, then unsigned shifts get 0, ashr
// saturates.
if (AmtSum >= TypeBits) {
if (I.getOpcode() != Instruction::AShr)
return ReplaceInstUsesWith(I, Constant::getNullValue(I.getType()));
AmtSum = TypeBits-1; // Saturate to 31 for i32 ashr.
}
return BinaryOperator::Create(I.getOpcode(), X,
ConstantInt::get(Ty, AmtSum));
}
if (ShiftAmt1 == ShiftAmt2) {
// If we have ((X << C) >>u C), turn this into X & (-1 >>u C).
if (I.getOpcode() == Instruction::LShr &&
ShiftOp->getOpcode() == Instruction::Shl) {
APInt Mask(APInt::getLowBitsSet(TypeBits, TypeBits - ShiftAmt1));
return BinaryOperator::CreateAnd(X,
ConstantInt::get(I.getContext(), Mask));
}
} else if (ShiftAmt1 < ShiftAmt2) {
uint32_t ShiftDiff = ShiftAmt2-ShiftAmt1;
// (X >>?,exact C1) << C2 --> X << (C2-C1)
// The inexact version is deferred to DAGCombine so we don't hide shl
// behind a bit mask.
if (I.getOpcode() == Instruction::Shl &&
ShiftOp->getOpcode() != Instruction::Shl &&
ShiftOp->isExact()) {
assert(ShiftOp->getOpcode() == Instruction::LShr ||
ShiftOp->getOpcode() == Instruction::AShr);
ConstantInt *ShiftDiffCst = ConstantInt::get(Ty, ShiftDiff);
BinaryOperator *NewShl = BinaryOperator::Create(Instruction::Shl,
X, ShiftDiffCst);
NewShl->setHasNoUnsignedWrap(I.hasNoUnsignedWrap());
NewShl->setHasNoSignedWrap(I.hasNoSignedWrap());
return NewShl;
}
// (X << C1) >>u C2 --> X >>u (C2-C1) & (-1 >> C2)
if (I.getOpcode() == Instruction::LShr &&
ShiftOp->getOpcode() == Instruction::Shl) {
ConstantInt *ShiftDiffCst = ConstantInt::get(Ty, ShiftDiff);
// (X <<nuw C1) >>u C2 --> X >>u (C2-C1)
if (ShiftOp->hasNoUnsignedWrap()) {
BinaryOperator *NewLShr = BinaryOperator::Create(Instruction::LShr,
X, ShiftDiffCst);
NewLShr->setIsExact(I.isExact());
return NewLShr;
}
Value *Shift = Builder->CreateLShr(X, ShiftDiffCst);
APInt Mask(APInt::getLowBitsSet(TypeBits, TypeBits - ShiftAmt2));
return BinaryOperator::CreateAnd(Shift,
ConstantInt::get(I.getContext(),Mask));
}
// We can't handle (X << C1) >>s C2, it shifts arbitrary bits in. However,
// we can handle (X <<nsw C1) >>s C2 since it only shifts in sign bits.
if (I.getOpcode() == Instruction::AShr &&
ShiftOp->getOpcode() == Instruction::Shl) {
if (ShiftOp->hasNoSignedWrap()) {
// (X <<nsw C1) >>s C2 --> X >>s (C2-C1)
ConstantInt *ShiftDiffCst = ConstantInt::get(Ty, ShiftDiff);
BinaryOperator *NewAShr = BinaryOperator::Create(Instruction::AShr,
X, ShiftDiffCst);
NewAShr->setIsExact(I.isExact());
return NewAShr;
}
}
} else {
assert(ShiftAmt2 < ShiftAmt1);
uint32_t ShiftDiff = ShiftAmt1-ShiftAmt2;
// (X >>?exact C1) << C2 --> X >>?exact (C1-C2)
// The inexact version is deferred to DAGCombine so we don't hide shl
// behind a bit mask.
if (I.getOpcode() == Instruction::Shl &&
ShiftOp->getOpcode() != Instruction::Shl &&
ShiftOp->isExact()) {
ConstantInt *ShiftDiffCst = ConstantInt::get(Ty, ShiftDiff);
BinaryOperator *NewShr = BinaryOperator::Create(ShiftOp->getOpcode(),
X, ShiftDiffCst);
NewShr->setIsExact(true);
return NewShr;
}
// (X << C1) >>u C2 --> X << (C1-C2) & (-1 >> C2)
if (I.getOpcode() == Instruction::LShr &&
ShiftOp->getOpcode() == Instruction::Shl) {
ConstantInt *ShiftDiffCst = ConstantInt::get(Ty, ShiftDiff);
if (ShiftOp->hasNoUnsignedWrap()) {
// (X <<nuw C1) >>u C2 --> X <<nuw (C1-C2)
BinaryOperator *NewShl = BinaryOperator::Create(Instruction::Shl,
X, ShiftDiffCst);
NewShl->setHasNoUnsignedWrap(true);
return NewShl;
}
Value *Shift = Builder->CreateShl(X, ShiftDiffCst);
APInt Mask(APInt::getLowBitsSet(TypeBits, TypeBits - ShiftAmt2));
return BinaryOperator::CreateAnd(Shift,
ConstantInt::get(I.getContext(),Mask));
}
// We can't handle (X << C1) >>s C2, it shifts arbitrary bits in. However,
// we can handle (X <<nsw C1) >>s C2 since it only shifts in sign bits.
if (I.getOpcode() == Instruction::AShr &&
ShiftOp->getOpcode() == Instruction::Shl) {
if (ShiftOp->hasNoSignedWrap()) {
// (X <<nsw C1) >>s C2 --> X <<nsw (C1-C2)
ConstantInt *ShiftDiffCst = ConstantInt::get(Ty, ShiftDiff);
BinaryOperator *NewShl = BinaryOperator::Create(Instruction::Shl,
X, ShiftDiffCst);
NewShl->setHasNoSignedWrap(true);
return NewShl;
}
}
}
}
return nullptr;
}
Instruction *InstCombiner::visitShl(BinaryOperator &I) {
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V =
SimplifyShlInst(I.getOperand(0), I.getOperand(1), I.hasNoSignedWrap(),
I.hasNoUnsignedWrap(), DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
if (Instruction *V = commonShiftTransforms(I))
return V;
if (ConstantInt *Op1C = dyn_cast<ConstantInt>(I.getOperand(1))) {
unsigned ShAmt = Op1C->getZExtValue();
// If the shifted-out value is known-zero, then this is a NUW shift.
if (!I.hasNoUnsignedWrap() &&
MaskedValueIsZero(I.getOperand(0),
APInt::getHighBitsSet(Op1C->getBitWidth(), ShAmt),
0, &I)) {
I.setHasNoUnsignedWrap();
return &I;
}
// If the shifted out value is all signbits, this is a NSW shift.
if (!I.hasNoSignedWrap() &&
ComputeNumSignBits(I.getOperand(0), 0, &I) > ShAmt) {
I.setHasNoSignedWrap();
return &I;
}
}
// (C1 << A) << C2 -> (C1 << C2) << A
Constant *C1, *C2;
Value *A;
if (match(I.getOperand(0), m_OneUse(m_Shl(m_Constant(C1), m_Value(A)))) &&
match(I.getOperand(1), m_Constant(C2)))
return BinaryOperator::CreateShl(ConstantExpr::getShl(C1, C2), A);
return nullptr;
}
Instruction *InstCombiner::visitLShr(BinaryOperator &I) {
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifyLShrInst(I.getOperand(0), I.getOperand(1), I.isExact(),
DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
if (Instruction *R = commonShiftTransforms(I))
return R;
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (ConstantInt *Op1C = dyn_cast<ConstantInt>(Op1)) {
unsigned ShAmt = Op1C->getZExtValue();
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(Op0)) {
unsigned BitWidth = Op0->getType()->getScalarSizeInBits();
// ctlz.i32(x)>>5 --> zext(x == 0)
// cttz.i32(x)>>5 --> zext(x == 0)
// ctpop.i32(x)>>5 --> zext(x == -1)
if ((II->getIntrinsicID() == Intrinsic::ctlz ||
II->getIntrinsicID() == Intrinsic::cttz ||
II->getIntrinsicID() == Intrinsic::ctpop) &&
isPowerOf2_32(BitWidth) && Log2_32(BitWidth) == ShAmt) {
bool isCtPop = II->getIntrinsicID() == Intrinsic::ctpop;
Constant *RHS = ConstantInt::getSigned(Op0->getType(), isCtPop ? -1:0);
Value *Cmp = Builder->CreateICmpEQ(II->getArgOperand(0), RHS);
return new ZExtInst(Cmp, II->getType());
}
}
// If the shifted-out value is known-zero, then this is an exact shift.
if (!I.isExact() &&
MaskedValueIsZero(Op0, APInt::getLowBitsSet(Op1C->getBitWidth(), ShAmt),
0, &I)){
I.setIsExact();
return &I;
}
}
return nullptr;
}
Instruction *InstCombiner::visitAShr(BinaryOperator &I) {
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifyAShrInst(I.getOperand(0), I.getOperand(1), I.isExact(),
DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
if (Instruction *R = commonShiftTransforms(I))
return R;
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (ConstantInt *Op1C = dyn_cast<ConstantInt>(Op1)) {
unsigned ShAmt = Op1C->getZExtValue();
// If the input is a SHL by the same constant (ashr (shl X, C), C), then we
// have a sign-extend idiom.
Value *X;
if (match(Op0, m_Shl(m_Value(X), m_Specific(Op1)))) {
// If the input is an extension from the shifted amount value, e.g.
// %x = zext i8 %A to i32
// %y = shl i32 %x, 24
// %z = ashr %y, 24
// then turn this into "z = sext i8 A to i32".
if (ZExtInst *ZI = dyn_cast<ZExtInst>(X)) {
uint32_t SrcBits = ZI->getOperand(0)->getType()->getScalarSizeInBits();
uint32_t DestBits = ZI->getType()->getScalarSizeInBits();
if (Op1C->getZExtValue() == DestBits-SrcBits)
return new SExtInst(ZI->getOperand(0), ZI->getType());
}
}
// If the shifted-out value is known-zero, then this is an exact shift.
if (!I.isExact() &&
MaskedValueIsZero(Op0,APInt::getLowBitsSet(Op1C->getBitWidth(),ShAmt),
0, &I)){
I.setIsExact();
return &I;
}
}
// See if we can turn a signed shr into an unsigned shr.
if (MaskedValueIsZero(Op0,
APInt::getSignBit(I.getType()->getScalarSizeInBits()),
0, &I))
return BinaryOperator::CreateLShr(Op0, Op1);
return nullptr;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/LowerInvoke.cpp | //===- LowerInvoke.cpp - Eliminate Invoke instructions --------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This transformation is designed for use by code generators which do not yet
// support stack unwinding. This pass converts 'invoke' instructions to 'call'
// instructions, so that any exception-handling 'landingpad' blocks become dead
// code (which can be removed by running the '-simplifycfg' pass afterwards).
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Scalar.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
using namespace llvm;
#define DEBUG_TYPE "lowerinvoke"
STATISTIC(NumInvokes, "Number of invokes replaced");
namespace {
class LowerInvoke : public FunctionPass {
public:
static char ID; // Pass identification, replacement for typeid
explicit LowerInvoke() : FunctionPass(ID) {
initializeLowerInvokePass(*PassRegistry::getPassRegistry());
}
bool runOnFunction(Function &F) override;
};
}
char LowerInvoke::ID = 0;
INITIALIZE_PASS(LowerInvoke, "lowerinvoke",
"Lower invoke and unwind, for unwindless code generators",
false, false)
char &llvm::LowerInvokePassID = LowerInvoke::ID;
// Public Interface To the LowerInvoke pass.
FunctionPass *llvm::createLowerInvokePass() {
return new LowerInvoke();
}
bool LowerInvoke::runOnFunction(Function &F) {
bool Changed = false;
for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
if (InvokeInst *II = dyn_cast<InvokeInst>(BB->getTerminator())) {
SmallVector<Value*,16> CallArgs(II->op_begin(), II->op_end() - 3);
// Insert a normal call instruction...
CallInst *NewCall = CallInst::Create(II->getCalledValue(),
CallArgs, "", II);
NewCall->takeName(II);
NewCall->setCallingConv(II->getCallingConv());
NewCall->setAttributes(II->getAttributes());
NewCall->setDebugLoc(II->getDebugLoc());
II->replaceAllUsesWith(NewCall);
// Insert an unconditional branch to the normal destination.
BranchInst::Create(II->getNormalDest(), II);
// Remove any PHI node entries from the exception destination.
II->getUnwindDest()->removePredecessor(BB);
// Remove the invoke instruction now.
BB->getInstList().erase(II);
++NumInvokes; Changed = true;
}
return Changed;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/SimplifyIndVar.cpp | //===-- SimplifyIndVar.cpp - Induction variable simplification ------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements induction variable simplification. It does
// not define any actual pass or policy, but provides a single function to
// simplify a loop's induction variables based on ScalarEvolution.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/SimplifyIndVar.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/LoopPass.h"
#include "llvm/Analysis/ScalarEvolutionExpressions.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
#define DEBUG_TYPE "indvars"
STATISTIC(NumElimIdentity, "Number of IV identities eliminated");
STATISTIC(NumElimOperand, "Number of IV operands folded into a use");
STATISTIC(NumElimRem , "Number of IV remainder operations eliminated");
STATISTIC(NumElimCmp , "Number of IV comparisons eliminated");
namespace {
/// This is a utility for simplifying induction variables
/// based on ScalarEvolution. It is the primary instrument of the
/// IndvarSimplify pass, but it may also be directly invoked to cleanup after
/// other loop passes that preserve SCEV.
class SimplifyIndvar {
Loop *L;
LoopInfo *LI;
ScalarEvolution *SE;
SmallVectorImpl<WeakTrackingVH> &DeadInsts;
bool Changed;
public:
SimplifyIndvar(Loop *Loop, ScalarEvolution *SE, LoopInfo *LI,
SmallVectorImpl<WeakTrackingVH> &Dead)
: L(Loop), LI(LI), SE(SE), DeadInsts(Dead), Changed(false) {
assert(LI && "IV simplification requires LoopInfo");
}
bool hasChanged() const { return Changed; }
/// Iteratively perform simplification on a worklist of users of the
/// specified induction variable. This is the top-level driver that applies
/// all simplicitions to users of an IV.
void simplifyUsers(PHINode *CurrIV, IVVisitor *V = nullptr);
Value *foldIVUser(Instruction *UseInst, Instruction *IVOperand);
bool eliminateIVUser(Instruction *UseInst, Instruction *IVOperand);
void eliminateIVComparison(ICmpInst *ICmp, Value *IVOperand);
void eliminateIVRemainder(BinaryOperator *Rem, Value *IVOperand,
bool IsSigned);
bool strengthenOverflowingOperation(BinaryOperator *OBO, Value *IVOperand);
Instruction *splitOverflowIntrinsic(Instruction *IVUser,
const DominatorTree *DT);
};
}
/// Fold an IV operand into its use. This removes increments of an
/// aligned IV when used by a instruction that ignores the low bits.
///
/// IVOperand is guaranteed SCEVable, but UseInst may not be.
///
/// Return the operand of IVOperand for this induction variable if IVOperand can
/// be folded (in case more folding opportunities have been exposed).
/// Otherwise return null.
Value *SimplifyIndvar::foldIVUser(Instruction *UseInst, Instruction *IVOperand) {
Value *IVSrc = nullptr;
unsigned OperIdx = 0;
const SCEV *FoldedExpr = nullptr;
switch (UseInst->getOpcode()) {
default:
return nullptr;
case Instruction::UDiv:
case Instruction::LShr:
// We're only interested in the case where we know something about
// the numerator and have a constant denominator.
if (IVOperand != UseInst->getOperand(OperIdx) ||
!isa<ConstantInt>(UseInst->getOperand(1)))
return nullptr;
// Attempt to fold a binary operator with constant operand.
// e.g. ((I + 1) >> 2) => I >> 2
if (!isa<BinaryOperator>(IVOperand)
|| !isa<ConstantInt>(IVOperand->getOperand(1)))
return nullptr;
IVSrc = IVOperand->getOperand(0);
// IVSrc must be the (SCEVable) IV, since the other operand is const.
assert(SE->isSCEVable(IVSrc->getType()) && "Expect SCEVable IV operand");
ConstantInt *D = cast<ConstantInt>(UseInst->getOperand(1));
if (UseInst->getOpcode() == Instruction::LShr) {
// Get a constant for the divisor. See createSCEV.
uint32_t BitWidth = cast<IntegerType>(UseInst->getType())->getBitWidth();
if (D->getValue().uge(BitWidth))
return nullptr;
D = ConstantInt::get(UseInst->getContext(),
APInt::getOneBitSet(BitWidth, D->getZExtValue()));
}
FoldedExpr = SE->getUDivExpr(SE->getSCEV(IVSrc), SE->getSCEV(D));
}
// We have something that might fold it's operand. Compare SCEVs.
if (!SE->isSCEVable(UseInst->getType()))
return nullptr;
// Bypass the operand if SCEV can prove it has no effect.
if (SE->getSCEV(UseInst) != FoldedExpr)
return nullptr;
DEBUG(dbgs() << "INDVARS: Eliminated IV operand: " << *IVOperand
<< " -> " << *UseInst << '\n');
UseInst->setOperand(OperIdx, IVSrc);
assert(SE->getSCEV(UseInst) == FoldedExpr && "bad SCEV with folded oper");
++NumElimOperand;
Changed = true;
if (IVOperand->use_empty())
DeadInsts.emplace_back(IVOperand);
return IVSrc;
}
/// SimplifyIVUsers helper for eliminating useless
/// comparisons against an induction variable.
void SimplifyIndvar::eliminateIVComparison(ICmpInst *ICmp, Value *IVOperand) {
unsigned IVOperIdx = 0;
ICmpInst::Predicate Pred = ICmp->getPredicate();
if (IVOperand != ICmp->getOperand(0)) {
// Swapped
assert(IVOperand == ICmp->getOperand(1) && "Can't find IVOperand");
IVOperIdx = 1;
Pred = ICmpInst::getSwappedPredicate(Pred);
}
// Get the SCEVs for the ICmp operands.
const SCEV *S = SE->getSCEV(ICmp->getOperand(IVOperIdx));
const SCEV *X = SE->getSCEV(ICmp->getOperand(1 - IVOperIdx));
// Simplify unnecessary loops away.
const Loop *ICmpLoop = LI->getLoopFor(ICmp->getParent());
S = SE->getSCEVAtScope(S, ICmpLoop);
X = SE->getSCEVAtScope(X, ICmpLoop);
// If the condition is always true or always false, replace it with
// a constant value.
if (SE->isKnownPredicate(Pred, S, X))
ICmp->replaceAllUsesWith(ConstantInt::getTrue(ICmp->getContext()));
else if (SE->isKnownPredicate(ICmpInst::getInversePredicate(Pred), S, X))
ICmp->replaceAllUsesWith(ConstantInt::getFalse(ICmp->getContext()));
else
return;
DEBUG(dbgs() << "INDVARS: Eliminated comparison: " << *ICmp << '\n');
++NumElimCmp;
Changed = true;
DeadInsts.emplace_back(ICmp);
}
/// SimplifyIVUsers helper for eliminating useless
/// remainder operations operating on an induction variable.
void SimplifyIndvar::eliminateIVRemainder(BinaryOperator *Rem,
Value *IVOperand,
bool IsSigned) {
// We're only interested in the case where we know something about
// the numerator.
if (IVOperand != Rem->getOperand(0))
return;
// Get the SCEVs for the ICmp operands.
const SCEV *S = SE->getSCEV(Rem->getOperand(0));
const SCEV *X = SE->getSCEV(Rem->getOperand(1));
// Simplify unnecessary loops away.
const Loop *ICmpLoop = LI->getLoopFor(Rem->getParent());
S = SE->getSCEVAtScope(S, ICmpLoop);
X = SE->getSCEVAtScope(X, ICmpLoop);
// i % n --> i if i is in [0,n).
if ((!IsSigned || SE->isKnownNonNegative(S)) &&
SE->isKnownPredicate(IsSigned ? ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT,
S, X))
Rem->replaceAllUsesWith(Rem->getOperand(0));
else {
// (i+1) % n --> (i+1)==n?0:(i+1) if i is in [0,n).
const SCEV *LessOne =
SE->getMinusSCEV(S, SE->getConstant(S->getType(), 1));
if (IsSigned && !SE->isKnownNonNegative(LessOne))
return;
if (!SE->isKnownPredicate(IsSigned ?
ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT,
LessOne, X))
return;
ICmpInst *ICmp = new ICmpInst(Rem, ICmpInst::ICMP_EQ,
Rem->getOperand(0), Rem->getOperand(1));
SelectInst *Sel =
SelectInst::Create(ICmp,
ConstantInt::get(Rem->getType(), 0),
Rem->getOperand(0), "tmp", Rem);
Rem->replaceAllUsesWith(Sel);
}
DEBUG(dbgs() << "INDVARS: Simplified rem: " << *Rem << '\n');
++NumElimRem;
Changed = true;
DeadInsts.emplace_back(Rem);
}
/// Eliminate an operation that consumes a simple IV and has
/// no observable side-effect given the range of IV values.
/// IVOperand is guaranteed SCEVable, but UseInst may not be.
bool SimplifyIndvar::eliminateIVUser(Instruction *UseInst,
Instruction *IVOperand) {
if (ICmpInst *ICmp = dyn_cast<ICmpInst>(UseInst)) {
eliminateIVComparison(ICmp, IVOperand);
return true;
}
if (BinaryOperator *Rem = dyn_cast<BinaryOperator>(UseInst)) {
bool IsSigned = Rem->getOpcode() == Instruction::SRem;
if (IsSigned || Rem->getOpcode() == Instruction::URem) {
eliminateIVRemainder(Rem, IVOperand, IsSigned);
return true;
}
}
// Eliminate any operation that SCEV can prove is an identity function.
if (!SE->isSCEVable(UseInst->getType()) ||
(UseInst->getType() != IVOperand->getType()) ||
(SE->getSCEV(UseInst) != SE->getSCEV(IVOperand)))
return false;
DEBUG(dbgs() << "INDVARS: Eliminated identity: " << *UseInst << '\n');
UseInst->replaceAllUsesWith(IVOperand);
++NumElimIdentity;
Changed = true;
DeadInsts.emplace_back(UseInst);
return true;
}
/// Annotate BO with nsw / nuw if it provably does not signed-overflow /
/// unsigned-overflow. Returns true if anything changed, false otherwise.
bool SimplifyIndvar::strengthenOverflowingOperation(BinaryOperator *BO,
Value *IVOperand) {
// Fastpath: we don't have any work to do if `BO` is `nuw` and `nsw`.
if (BO->hasNoUnsignedWrap() && BO->hasNoSignedWrap())
return false;
const SCEV *(ScalarEvolution::*GetExprForBO)(const SCEV *, const SCEV *,
SCEV::NoWrapFlags);
switch (BO->getOpcode()) {
default:
return false;
case Instruction::Add:
GetExprForBO = &ScalarEvolution::getAddExpr;
break;
case Instruction::Sub:
GetExprForBO = &ScalarEvolution::getMinusSCEV;
break;
case Instruction::Mul:
GetExprForBO = &ScalarEvolution::getMulExpr;
break;
}
unsigned BitWidth = cast<IntegerType>(BO->getType())->getBitWidth();
Type *WideTy = IntegerType::get(BO->getContext(), BitWidth * 2);
const SCEV *LHS = SE->getSCEV(BO->getOperand(0));
const SCEV *RHS = SE->getSCEV(BO->getOperand(1));
bool Changed = false;
if (!BO->hasNoUnsignedWrap()) {
const SCEV *ExtendAfterOp = SE->getZeroExtendExpr(SE->getSCEV(BO), WideTy);
const SCEV *OpAfterExtend = (SE->*GetExprForBO)(
SE->getZeroExtendExpr(LHS, WideTy), SE->getZeroExtendExpr(RHS, WideTy),
SCEV::FlagAnyWrap);
if (ExtendAfterOp == OpAfterExtend) {
BO->setHasNoUnsignedWrap();
SE->forgetValue(BO);
Changed = true;
}
}
if (!BO->hasNoSignedWrap()) {
const SCEV *ExtendAfterOp = SE->getSignExtendExpr(SE->getSCEV(BO), WideTy);
const SCEV *OpAfterExtend = (SE->*GetExprForBO)(
SE->getSignExtendExpr(LHS, WideTy), SE->getSignExtendExpr(RHS, WideTy),
SCEV::FlagAnyWrap);
if (ExtendAfterOp == OpAfterExtend) {
BO->setHasNoSignedWrap();
SE->forgetValue(BO);
Changed = true;
}
}
return Changed;
}
/// \brief Split sadd.with.overflow into add + sadd.with.overflow to allow
/// analysis and optimization.
///
/// \return A new value representing the non-overflowing add if possible,
/// otherwise return the original value.
Instruction *SimplifyIndvar::splitOverflowIntrinsic(Instruction *IVUser,
const DominatorTree *DT) {
IntrinsicInst *II = dyn_cast<IntrinsicInst>(IVUser);
if (!II || II->getIntrinsicID() != Intrinsic::sadd_with_overflow)
return IVUser;
// Find a branch guarded by the overflow check.
BranchInst *Branch = nullptr;
Instruction *AddVal = nullptr;
for (User *U : II->users()) {
if (ExtractValueInst *ExtractInst = dyn_cast<ExtractValueInst>(U)) {
if (ExtractInst->getNumIndices() != 1)
continue;
if (ExtractInst->getIndices()[0] == 0)
AddVal = ExtractInst;
else if (ExtractInst->getIndices()[0] == 1 && ExtractInst->hasOneUse())
Branch = dyn_cast<BranchInst>(ExtractInst->user_back());
}
}
if (!AddVal || !Branch)
return IVUser;
BasicBlock *ContinueBB = Branch->getSuccessor(1);
if (std::next(pred_begin(ContinueBB)) != pred_end(ContinueBB))
return IVUser;
// Check if all users of the add are provably NSW.
bool AllNSW = true;
for (Use &U : AddVal->uses()) {
if (Instruction *UseInst = dyn_cast<Instruction>(U.getUser())) {
BasicBlock *UseBB = UseInst->getParent();
if (PHINode *PHI = dyn_cast<PHINode>(UseInst))
UseBB = PHI->getIncomingBlock(U);
if (!DT->dominates(ContinueBB, UseBB)) {
AllNSW = false;
break;
}
}
}
if (!AllNSW)
return IVUser;
// Go for it...
IRBuilder<> Builder(IVUser);
Instruction *AddInst = dyn_cast<Instruction>(
Builder.CreateNSWAdd(II->getOperand(0), II->getOperand(1)));
// The caller expects the new add to have the same form as the intrinsic. The
// IV operand position must be the same.
assert((AddInst->getOpcode() == Instruction::Add &&
AddInst->getOperand(0) == II->getOperand(0)) &&
"Bad add instruction created from overflow intrinsic.");
AddVal->replaceAllUsesWith(AddInst);
DeadInsts.emplace_back(AddVal);
return AddInst;
}
/// Add all uses of Def to the current IV's worklist.
static void pushIVUsers(
Instruction *Def,
SmallPtrSet<Instruction*,16> &Simplified,
SmallVectorImpl< std::pair<Instruction*,Instruction*> > &SimpleIVUsers) {
for (User *U : Def->users()) {
Instruction *UI = cast<Instruction>(U);
// Avoid infinite or exponential worklist processing.
// Also ensure unique worklist users.
// If Def is a LoopPhi, it may not be in the Simplified set, so check for
// self edges first.
if (UI != Def && Simplified.insert(UI).second)
SimpleIVUsers.push_back(std::make_pair(UI, Def));
}
}
/// Return true if this instruction generates a simple SCEV
/// expression in terms of that IV.
///
/// This is similar to IVUsers' isInteresting() but processes each instruction
/// non-recursively when the operand is already known to be a simpleIVUser.
///
static bool isSimpleIVUser(Instruction *I, const Loop *L, ScalarEvolution *SE) {
if (!SE->isSCEVable(I->getType()))
return false;
// Get the symbolic expression for this instruction.
const SCEV *S = SE->getSCEV(I);
// Only consider affine recurrences.
const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(S);
if (AR && AR->getLoop() == L)
return true;
return false;
}
/// Iteratively perform simplification on a worklist of users
/// of the specified induction variable. Each successive simplification may push
/// more users which may themselves be candidates for simplification.
///
/// This algorithm does not require IVUsers analysis. Instead, it simplifies
/// instructions in-place during analysis. Rather than rewriting induction
/// variables bottom-up from their users, it transforms a chain of IVUsers
/// top-down, updating the IR only when it encouters a clear optimization
/// opportunitiy.
///
/// Once DisableIVRewrite is default, LSR will be the only client of IVUsers.
///
void SimplifyIndvar::simplifyUsers(PHINode *CurrIV, IVVisitor *V) {
if (!SE->isSCEVable(CurrIV->getType()))
return;
// Instructions processed by SimplifyIndvar for CurrIV.
SmallPtrSet<Instruction*,16> Simplified;
// Use-def pairs if IV users waiting to be processed for CurrIV.
SmallVector<std::pair<Instruction*, Instruction*>, 8> SimpleIVUsers;
// Push users of the current LoopPhi. In rare cases, pushIVUsers may be
// called multiple times for the same LoopPhi. This is the proper thing to
// do for loop header phis that use each other.
pushIVUsers(CurrIV, Simplified, SimpleIVUsers);
while (!SimpleIVUsers.empty()) {
std::pair<Instruction*, Instruction*> UseOper =
SimpleIVUsers.pop_back_val();
Instruction *UseInst = UseOper.first;
// Bypass back edges to avoid extra work.
if (UseInst == CurrIV) continue;
if (V && V->shouldSplitOverflowInstrinsics()) {
UseInst = splitOverflowIntrinsic(UseInst, V->getDomTree());
if (!UseInst)
continue;
}
Instruction *IVOperand = UseOper.second;
for (unsigned N = 0; IVOperand; ++N) {
assert(N <= Simplified.size() && "runaway iteration");
Value *NewOper = foldIVUser(UseOper.first, IVOperand);
if (!NewOper)
break; // done folding
IVOperand = dyn_cast<Instruction>(NewOper);
}
if (!IVOperand)
continue;
if (eliminateIVUser(UseOper.first, IVOperand)) {
pushIVUsers(IVOperand, Simplified, SimpleIVUsers);
continue;
}
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(UseOper.first)) {
if (isa<OverflowingBinaryOperator>(BO) &&
strengthenOverflowingOperation(BO, IVOperand)) {
// re-queue uses of the now modified binary operator and fall
// through to the checks that remain.
pushIVUsers(IVOperand, Simplified, SimpleIVUsers);
}
}
CastInst *Cast = dyn_cast<CastInst>(UseOper.first);
if (V && Cast) {
V->visitCast(Cast);
continue;
}
if (isSimpleIVUser(UseOper.first, L, SE)) {
pushIVUsers(UseOper.first, Simplified, SimpleIVUsers);
}
}
}
namespace llvm {
void IVVisitor::anchor() { }
/// Simplify instructions that use this induction variable
/// by using ScalarEvolution to analyze the IV's recurrence.
bool simplifyUsersOfIV(PHINode *CurrIV, ScalarEvolution *SE, LPPassManager *LPM,
SmallVectorImpl<WeakTrackingVH> &Dead, IVVisitor *V) {
LoopInfo *LI = &LPM->getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
SimplifyIndvar SIV(LI->getLoopFor(CurrIV->getParent()), SE, LI, Dead);
SIV.simplifyUsers(CurrIV, V);
return SIV.hasChanged();
}
/// Simplify users of induction variables within this
/// loop. This does not actually change or add IVs.
bool simplifyLoopIVs(Loop *L, ScalarEvolution *SE, LPPassManager *LPM,
SmallVectorImpl<WeakTrackingVH> &Dead) {
bool Changed = false;
for (BasicBlock::iterator I = L->getHeader()->begin(); isa<PHINode>(I); ++I) {
Changed |= simplifyUsersOfIV(cast<PHINode>(I), SE, LPM, Dead);
}
return Changed;
}
} // namespace llvm
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/SymbolRewriter.cpp | //===- SymbolRewriter.cpp - Symbol Rewriter ---------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// SymbolRewriter is a LLVM pass which can rewrite symbols transparently within
// existing code. It is implemented as a compiler pass and is configured via a
// YAML configuration file.
//
// The YAML configuration file format is as follows:
//
// RewriteMapFile := RewriteDescriptors
// RewriteDescriptors := RewriteDescriptor | RewriteDescriptors
// RewriteDescriptor := RewriteDescriptorType ':' '{' RewriteDescriptorFields '}'
// RewriteDescriptorFields := RewriteDescriptorField | RewriteDescriptorFields
// RewriteDescriptorField := FieldIdentifier ':' FieldValue ','
// RewriteDescriptorType := Identifier
// FieldIdentifier := Identifier
// FieldValue := Identifier
// Identifier := [0-9a-zA-Z]+
//
// Currently, the following descriptor types are supported:
//
// - function: (function rewriting)
// + Source (original name of the function)
// + Target (explicit transformation)
// + Transform (pattern transformation)
// + Naked (boolean, whether the function is undecorated)
// - global variable: (external linkage global variable rewriting)
// + Source (original name of externally visible variable)
// + Target (explicit transformation)
// + Transform (pattern transformation)
// - global alias: (global alias rewriting)
// + Source (original name of the aliased name)
// + Target (explicit transformation)
// + Transform (pattern transformation)
//
// Note that source and exactly one of [Target, Transform] must be provided
//
// New rewrite descriptors can be created. Addding a new rewrite descriptor
// involves:
//
// a) extended the rewrite descriptor kind enumeration
// (<anonymous>::RewriteDescriptor::RewriteDescriptorType)
// b) implementing the new descriptor
// (c.f. <anonymous>::ExplicitRewriteFunctionDescriptor)
// c) extending the rewrite map parser
// (<anonymous>::RewriteMapParser::parseEntry)
//
// Specify to rewrite the symbols using the `-rewrite-symbols` option, and
// specify the map file to use for the rewriting via the `-rewrite-map-file`
// option.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "symbol-rewriter"
#include "llvm/CodeGen/Passes.h"
#include "llvm/Pass.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/Regex.h"
#include "llvm/Support/SourceMgr.h"
#include "llvm/Support/YAMLParser.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/IPO/PassManagerBuilder.h"
#include "llvm/Transforms/Utils/SymbolRewriter.h"
using namespace llvm;
using namespace SymbolRewriter;
#if 0 // HLSL Change Starts - option pending
static cl::list<std::string> RewriteMapFiles("rewrite-map-file",
cl::desc("Symbol Rewrite Map"),
cl::value_desc("filename"));
#endif // HLSL Change Ends
static void rewriteComdat(Module &M, GlobalObject *GO,
const std::string &Source,
const std::string &Target) {
if (Comdat *CD = GO->getComdat()) {
auto &Comdats = M.getComdatSymbolTable();
Comdat *C = M.getOrInsertComdat(Target);
C->setSelectionKind(CD->getSelectionKind());
GO->setComdat(C);
Comdats.erase(Comdats.find(Source));
}
}
namespace {
template <RewriteDescriptor::Type DT, typename ValueType,
ValueType *(llvm::Module::*Get)(StringRef) const>
class ExplicitRewriteDescriptor : public RewriteDescriptor {
public:
const std::string Source;
const std::string Target;
ExplicitRewriteDescriptor(StringRef S, StringRef T, const bool Naked)
: RewriteDescriptor(DT), Source(Naked ? StringRef("\01" + S.str()) : S),
Target(T) {}
bool performOnModule(Module &M) override;
static bool classof(const RewriteDescriptor *RD) {
return RD->getType() == DT;
}
};
template <RewriteDescriptor::Type DT, typename ValueType,
ValueType *(llvm::Module::*Get)(StringRef) const>
bool ExplicitRewriteDescriptor<DT, ValueType, Get>::performOnModule(Module &M) {
bool Changed = false;
if (ValueType *S = (M.*Get)(Source)) {
if (GlobalObject *GO = dyn_cast<GlobalObject>(S))
rewriteComdat(M, GO, Source, Target);
if (Value *T = (M.*Get)(Target))
S->setValueName(T->getValueName());
else
S->setName(Target);
Changed = true;
}
return Changed;
}
template <RewriteDescriptor::Type DT, typename ValueType,
ValueType *(llvm::Module::*Get)(StringRef) const,
iterator_range<typename iplist<ValueType>::iterator>
(llvm::Module::*Iterator)()>
class PatternRewriteDescriptor : public RewriteDescriptor {
public:
const std::string Pattern;
const std::string Transform;
PatternRewriteDescriptor(StringRef P, StringRef T)
: RewriteDescriptor(DT), Pattern(P), Transform(T) { }
bool performOnModule(Module &M) override;
static bool classof(const RewriteDescriptor *RD) {
return RD->getType() == DT;
}
};
template <RewriteDescriptor::Type DT, typename ValueType,
ValueType *(llvm::Module::*Get)(StringRef) const,
iterator_range<typename iplist<ValueType>::iterator>
(llvm::Module::*Iterator)()>
bool PatternRewriteDescriptor<DT, ValueType, Get, Iterator>::
performOnModule(Module &M) {
bool Changed = false;
for (auto &C : (M.*Iterator)()) {
std::string Error;
std::string Name = Regex(Pattern).sub(Transform, C.getName(), &Error);
if (!Error.empty())
report_fatal_error("unable to transforn " + C.getName() + " in " +
M.getModuleIdentifier() + ": " + Error);
if (C.getName() == Name)
continue;
if (GlobalObject *GO = dyn_cast<GlobalObject>(&C))
rewriteComdat(M, GO, C.getName(), Name);
if (Value *V = (M.*Get)(Name))
C.setValueName(V->getValueName());
else
C.setName(Name);
Changed = true;
}
return Changed;
}
/// Represents a rewrite for an explicitly named (function) symbol. Both the
/// source function name and target function name of the transformation are
/// explicitly spelt out.
typedef ExplicitRewriteDescriptor<RewriteDescriptor::Type::Function,
llvm::Function, &llvm::Module::getFunction>
ExplicitRewriteFunctionDescriptor;
/// Represents a rewrite for an explicitly named (global variable) symbol. Both
/// the source variable name and target variable name are spelt out. This
/// applies only to module level variables.
typedef ExplicitRewriteDescriptor<RewriteDescriptor::Type::GlobalVariable,
llvm::GlobalVariable,
&llvm::Module::getGlobalVariable>
ExplicitRewriteGlobalVariableDescriptor;
/// Represents a rewrite for an explicitly named global alias. Both the source
/// and target name are explicitly spelt out.
typedef ExplicitRewriteDescriptor<RewriteDescriptor::Type::NamedAlias,
llvm::GlobalAlias,
&llvm::Module::getNamedAlias>
ExplicitRewriteNamedAliasDescriptor;
/// Represents a rewrite for a regular expression based pattern for functions.
/// A pattern for the function name is provided and a transformation for that
/// pattern to determine the target function name create the rewrite rule.
typedef PatternRewriteDescriptor<RewriteDescriptor::Type::Function,
llvm::Function, &llvm::Module::getFunction,
&llvm::Module::functions>
PatternRewriteFunctionDescriptor;
/// Represents a rewrite for a global variable based upon a matching pattern.
/// Each global variable matching the provided pattern will be transformed as
/// described in the transformation pattern for the target. Applies only to
/// module level variables.
typedef PatternRewriteDescriptor<RewriteDescriptor::Type::GlobalVariable,
llvm::GlobalVariable,
&llvm::Module::getGlobalVariable,
&llvm::Module::globals>
PatternRewriteGlobalVariableDescriptor;
/// PatternRewriteNamedAliasDescriptor - represents a rewrite for global
/// aliases which match a given pattern. The provided transformation will be
/// applied to each of the matching names.
typedef PatternRewriteDescriptor<RewriteDescriptor::Type::NamedAlias,
llvm::GlobalAlias,
&llvm::Module::getNamedAlias,
&llvm::Module::aliases>
PatternRewriteNamedAliasDescriptor;
} // namespace
bool RewriteMapParser::parse(const std::string &MapFile,
RewriteDescriptorList *DL) {
ErrorOr<std::unique_ptr<MemoryBuffer>> Mapping =
MemoryBuffer::getFile(MapFile);
if (!Mapping)
report_fatal_error("unable to read rewrite map '" + MapFile + "': " +
Mapping.getError().message());
if (!parse(*Mapping, DL))
report_fatal_error("unable to parse rewrite map '" + MapFile + "'");
return true;
}
bool RewriteMapParser::parse(std::unique_ptr<MemoryBuffer> &MapFile,
RewriteDescriptorList *DL) {
SourceMgr SM;
yaml::Stream YS(MapFile->getBuffer(), SM);
for (auto &Document : YS) {
yaml::MappingNode *DescriptorList;
// ignore empty documents
if (isa<yaml::NullNode>(Document.getRoot()))
continue;
DescriptorList = dyn_cast<yaml::MappingNode>(Document.getRoot());
if (!DescriptorList) {
YS.printError(Document.getRoot(), "DescriptorList node must be a map");
return false;
}
for (auto &Descriptor : *DescriptorList)
if (!parseEntry(YS, Descriptor, DL))
return false;
}
return true;
}
bool RewriteMapParser::parseEntry(yaml::Stream &YS, yaml::KeyValueNode &Entry,
RewriteDescriptorList *DL) {
yaml::ScalarNode *Key;
yaml::MappingNode *Value;
SmallString<32> KeyStorage;
StringRef RewriteType;
Key = dyn_cast<yaml::ScalarNode>(Entry.getKey());
if (!Key) {
YS.printError(Entry.getKey(), "rewrite type must be a scalar");
return false;
}
Value = dyn_cast<yaml::MappingNode>(Entry.getValue());
if (!Value) {
YS.printError(Entry.getValue(), "rewrite descriptor must be a map");
return false;
}
RewriteType = Key->getValue(KeyStorage);
if (RewriteType.equals("function"))
return parseRewriteFunctionDescriptor(YS, Key, Value, DL);
else if (RewriteType.equals("global variable"))
return parseRewriteGlobalVariableDescriptor(YS, Key, Value, DL);
else if (RewriteType.equals("global alias"))
return parseRewriteGlobalAliasDescriptor(YS, Key, Value, DL);
YS.printError(Entry.getKey(), "unknown rewrite type");
return false;
}
bool RewriteMapParser::
parseRewriteFunctionDescriptor(yaml::Stream &YS, yaml::ScalarNode *K,
yaml::MappingNode *Descriptor,
RewriteDescriptorList *DL) {
bool Naked = false;
std::string Source;
std::string Target;
std::string Transform;
for (auto &Field : *Descriptor) {
yaml::ScalarNode *Key;
yaml::ScalarNode *Value;
SmallString<32> KeyStorage;
SmallString<32> ValueStorage;
StringRef KeyValue;
Key = dyn_cast<yaml::ScalarNode>(Field.getKey());
if (!Key) {
YS.printError(Field.getKey(), "descriptor key must be a scalar");
return false;
}
Value = dyn_cast<yaml::ScalarNode>(Field.getValue());
if (!Value) {
YS.printError(Field.getValue(), "descriptor value must be a scalar");
return false;
}
KeyValue = Key->getValue(KeyStorage);
if (KeyValue.equals("source")) {
std::string Error;
Source = Value->getValue(ValueStorage);
if (!Regex(Source).isValid(Error)) {
YS.printError(Field.getKey(), "invalid regex: " + Error);
return false;
}
} else if (KeyValue.equals("target")) {
Target = Value->getValue(ValueStorage);
} else if (KeyValue.equals("transform")) {
Transform = Value->getValue(ValueStorage);
} else if (KeyValue.equals("naked")) {
std::string Undecorated;
Undecorated = Value->getValue(ValueStorage);
Naked = StringRef(Undecorated).lower() == "true" || Undecorated == "1";
} else {
YS.printError(Field.getKey(), "unknown key for function");
return false;
}
}
if (Transform.empty() == Target.empty()) {
YS.printError(Descriptor,
"exactly one of transform or target must be specified");
return false;
}
// TODO see if there is a more elegant solution to selecting the rewrite
// descriptor type
if (!Target.empty())
DL->push_back(new ExplicitRewriteFunctionDescriptor(Source, Target, Naked));
else
DL->push_back(new PatternRewriteFunctionDescriptor(Source, Transform));
return true;
}
bool RewriteMapParser::
parseRewriteGlobalVariableDescriptor(yaml::Stream &YS, yaml::ScalarNode *K,
yaml::MappingNode *Descriptor,
RewriteDescriptorList *DL) {
std::string Source;
std::string Target;
std::string Transform;
for (auto &Field : *Descriptor) {
yaml::ScalarNode *Key;
yaml::ScalarNode *Value;
SmallString<32> KeyStorage;
SmallString<32> ValueStorage;
StringRef KeyValue;
Key = dyn_cast<yaml::ScalarNode>(Field.getKey());
if (!Key) {
YS.printError(Field.getKey(), "descriptor Key must be a scalar");
return false;
}
Value = dyn_cast<yaml::ScalarNode>(Field.getValue());
if (!Value) {
YS.printError(Field.getValue(), "descriptor value must be a scalar");
return false;
}
KeyValue = Key->getValue(KeyStorage);
if (KeyValue.equals("source")) {
std::string Error;
Source = Value->getValue(ValueStorage);
if (!Regex(Source).isValid(Error)) {
YS.printError(Field.getKey(), "invalid regex: " + Error);
return false;
}
} else if (KeyValue.equals("target")) {
Target = Value->getValue(ValueStorage);
} else if (KeyValue.equals("transform")) {
Transform = Value->getValue(ValueStorage);
} else {
YS.printError(Field.getKey(), "unknown Key for Global Variable");
return false;
}
}
if (Transform.empty() == Target.empty()) {
YS.printError(Descriptor,
"exactly one of transform or target must be specified");
return false;
}
if (!Target.empty())
DL->push_back(new ExplicitRewriteGlobalVariableDescriptor(Source, Target,
/*Naked*/false));
else
DL->push_back(new PatternRewriteGlobalVariableDescriptor(Source,
Transform));
return true;
}
bool RewriteMapParser::
parseRewriteGlobalAliasDescriptor(yaml::Stream &YS, yaml::ScalarNode *K,
yaml::MappingNode *Descriptor,
RewriteDescriptorList *DL) {
std::string Source;
std::string Target;
std::string Transform;
for (auto &Field : *Descriptor) {
yaml::ScalarNode *Key;
yaml::ScalarNode *Value;
SmallString<32> KeyStorage;
SmallString<32> ValueStorage;
StringRef KeyValue;
Key = dyn_cast<yaml::ScalarNode>(Field.getKey());
if (!Key) {
YS.printError(Field.getKey(), "descriptor key must be a scalar");
return false;
}
Value = dyn_cast<yaml::ScalarNode>(Field.getValue());
if (!Value) {
YS.printError(Field.getValue(), "descriptor value must be a scalar");
return false;
}
KeyValue = Key->getValue(KeyStorage);
if (KeyValue.equals("source")) {
std::string Error;
Source = Value->getValue(ValueStorage);
if (!Regex(Source).isValid(Error)) {
YS.printError(Field.getKey(), "invalid regex: " + Error);
return false;
}
} else if (KeyValue.equals("target")) {
Target = Value->getValue(ValueStorage);
} else if (KeyValue.equals("transform")) {
Transform = Value->getValue(ValueStorage);
} else {
YS.printError(Field.getKey(), "unknown key for Global Alias");
return false;
}
}
if (Transform.empty() == Target.empty()) {
YS.printError(Descriptor,
"exactly one of transform or target must be specified");
return false;
}
if (!Target.empty())
DL->push_back(new ExplicitRewriteNamedAliasDescriptor(Source, Target,
/*Naked*/false));
else
DL->push_back(new PatternRewriteNamedAliasDescriptor(Source, Transform));
return true;
}
namespace {
class RewriteSymbols : public ModulePass {
public:
static char ID; // Pass identification, replacement for typeid
RewriteSymbols();
RewriteSymbols(SymbolRewriter::RewriteDescriptorList &DL);
bool runOnModule(Module &M) override;
private:
void loadAndParseMapFiles();
SymbolRewriter::RewriteDescriptorList Descriptors;
};
char RewriteSymbols::ID = 0;
RewriteSymbols::RewriteSymbols() : ModulePass(ID) {
initializeRewriteSymbolsPass(*PassRegistry::getPassRegistry());
loadAndParseMapFiles();
}
RewriteSymbols::RewriteSymbols(SymbolRewriter::RewriteDescriptorList &DL)
: ModulePass(ID) {
Descriptors.splice(Descriptors.begin(), DL);
}
bool RewriteSymbols::runOnModule(Module &M) {
bool Changed;
Changed = false;
for (auto &Descriptor : Descriptors)
Changed |= Descriptor.performOnModule(M);
return Changed;
}
void RewriteSymbols::loadAndParseMapFiles() {
const std::vector<std::string> MapFiles; // HLSL Change - do not init from a global RewriteMapFiles
SymbolRewriter::RewriteMapParser parser;
for (const auto &MapFile : MapFiles)
parser.parse(MapFile, &Descriptors);
}
}
INITIALIZE_PASS(RewriteSymbols, "rewrite-symbols", "Rewrite Symbols", false,
false)
ModulePass *llvm::createRewriteSymbolsPass() { return new RewriteSymbols(); }
ModulePass *
llvm::createRewriteSymbolsPass(SymbolRewriter::RewriteDescriptorList &DL) {
return new RewriteSymbols(DL);
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/ValueMapper.cpp | //===- ValueMapper.cpp - Interface shared by lib/Transforms/Utils ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the MapValue function, which is shared by various parts of
// the lib/Transforms/Utils library.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/ValueMapper.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/InlineAsm.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Metadata.h"
using namespace llvm;
// Out of line method to get vtable etc for class.
void ValueMapTypeRemapper::anchor() {}
void ValueMaterializer::anchor() {}
Value *llvm::MapValue(const Value *V, ValueToValueMapTy &VM, RemapFlags Flags,
ValueMapTypeRemapper *TypeMapper,
ValueMaterializer *Materializer) {
ValueToValueMapTy::iterator I = VM.find(V);
// If the value already exists in the map, use it.
if (I != VM.end() && I->second) return I->second;
// If we have a materializer and it can materialize a value, use that.
if (Materializer) {
if (Value *NewV = Materializer->materializeValueFor(const_cast<Value*>(V)))
return VM[V] = NewV;
}
// Global values do not need to be seeded into the VM if they
// are using the identity mapping.
if (isa<GlobalValue>(V))
return VM[V] = const_cast<Value*>(V);
if (const InlineAsm *IA = dyn_cast<InlineAsm>(V)) {
// Inline asm may need *type* remapping.
FunctionType *NewTy = IA->getFunctionType();
if (TypeMapper) {
NewTy = cast<FunctionType>(TypeMapper->remapType(NewTy));
if (NewTy != IA->getFunctionType())
V = InlineAsm::get(NewTy, IA->getAsmString(), IA->getConstraintString(),
IA->hasSideEffects(), IA->isAlignStack());
}
return VM[V] = const_cast<Value*>(V);
}
if (const auto *MDV = dyn_cast<MetadataAsValue>(V)) {
const Metadata *MD = MDV->getMetadata();
// If this is a module-level metadata and we know that nothing at the module
// level is changing, then use an identity mapping.
if (!isa<LocalAsMetadata>(MD) && (Flags & RF_NoModuleLevelChanges))
return VM[V] = const_cast<Value *>(V);
auto *MappedMD = MapMetadata(MD, VM, Flags, TypeMapper, Materializer);
if (MD == MappedMD || (!MappedMD && (Flags & RF_IgnoreMissingEntries)))
return VM[V] = const_cast<Value *>(V);
// FIXME: This assert crashes during bootstrap, but I think it should be
// correct. For now, just match behaviour from before the metadata/value
// split.
//
// assert(MappedMD && "Referenced metadata value not in value map");
return VM[V] = MetadataAsValue::get(V->getContext(), MappedMD);
}
// Okay, this either must be a constant (which may or may not be mappable) or
// is something that is not in the mapping table.
Constant *C = const_cast<Constant*>(dyn_cast<Constant>(V));
if (!C)
return nullptr;
if (BlockAddress *BA = dyn_cast<BlockAddress>(C)) {
Function *F =
cast<Function>(MapValue(BA->getFunction(), VM, Flags, TypeMapper, Materializer));
BasicBlock *BB = cast_or_null<BasicBlock>(MapValue(BA->getBasicBlock(), VM,
Flags, TypeMapper, Materializer));
return VM[V] = BlockAddress::get(F, BB ? BB : BA->getBasicBlock());
}
// Otherwise, we have some other constant to remap. Start by checking to see
// if all operands have an identity remapping.
unsigned OpNo = 0, NumOperands = C->getNumOperands();
Value *Mapped = nullptr;
for (; OpNo != NumOperands; ++OpNo) {
Value *Op = C->getOperand(OpNo);
Mapped = MapValue(Op, VM, Flags, TypeMapper, Materializer);
if (Mapped != C) break;
}
// See if the type mapper wants to remap the type as well.
Type *NewTy = C->getType();
if (TypeMapper)
NewTy = TypeMapper->remapType(NewTy);
// If the result type and all operands match up, then just insert an identity
// mapping.
if (OpNo == NumOperands && NewTy == C->getType())
return VM[V] = C;
// Okay, we need to create a new constant. We've already processed some or
// all of the operands, set them all up now.
SmallVector<Constant*, 8> Ops;
Ops.reserve(NumOperands);
for (unsigned j = 0; j != OpNo; ++j)
Ops.push_back(cast<Constant>(C->getOperand(j)));
// If one of the operands mismatch, push it and the other mapped operands.
if (OpNo != NumOperands) {
Ops.push_back(cast<Constant>(Mapped));
// Map the rest of the operands that aren't processed yet.
for (++OpNo; OpNo != NumOperands; ++OpNo)
Ops.push_back(MapValue(cast<Constant>(C->getOperand(OpNo)), VM,
Flags, TypeMapper, Materializer));
}
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C))
return VM[V] = CE->getWithOperands(Ops, NewTy);
if (isa<ConstantArray>(C))
return VM[V] = ConstantArray::get(cast<ArrayType>(NewTy), Ops);
if (isa<ConstantStruct>(C))
return VM[V] = ConstantStruct::get(cast<StructType>(NewTy), Ops);
if (isa<ConstantVector>(C))
return VM[V] = ConstantVector::get(Ops);
// If this is a no-operand constant, it must be because the type was remapped.
if (isa<UndefValue>(C))
return VM[V] = UndefValue::get(NewTy);
if (isa<ConstantAggregateZero>(C))
return VM[V] = ConstantAggregateZero::get(NewTy);
assert(isa<ConstantPointerNull>(C));
return VM[V] = ConstantPointerNull::get(cast<PointerType>(NewTy));
}
static Metadata *mapToMetadata(ValueToValueMapTy &VM, const Metadata *Key,
Metadata *Val) {
VM.MD()[Key].reset(Val);
return Val;
}
static Metadata *mapToSelf(ValueToValueMapTy &VM, const Metadata *MD) {
return mapToMetadata(VM, MD, const_cast<Metadata *>(MD));
}
static Metadata *MapMetadataImpl(const Metadata *MD,
SmallVectorImpl<MDNode *> &Cycles,
ValueToValueMapTy &VM, RemapFlags Flags,
ValueMapTypeRemapper *TypeMapper,
ValueMaterializer *Materializer);
static Metadata *mapMetadataOp(Metadata *Op, SmallVectorImpl<MDNode *> &Cycles,
ValueToValueMapTy &VM, RemapFlags Flags,
ValueMapTypeRemapper *TypeMapper,
ValueMaterializer *Materializer) {
if (!Op)
return nullptr;
if (Metadata *MappedOp =
MapMetadataImpl(Op, Cycles, VM, Flags, TypeMapper, Materializer))
return MappedOp;
// Use identity map if MappedOp is null and we can ignore missing entries.
if (Flags & RF_IgnoreMissingEntries)
return Op;
// FIXME: This assert crashes during bootstrap, but I think it should be
// correct. For now, just match behaviour from before the metadata/value
// split.
//
// llvm_unreachable("Referenced metadata not in value map!");
return nullptr;
}
/// \brief Remap nodes.
///
/// Insert \c NewNode in the value map, and then remap \c OldNode's operands.
/// Assumes that \c NewNode is already a clone of \c OldNode.
///
/// \pre \c NewNode is a clone of \c OldNode.
static bool remap(const MDNode *OldNode, MDNode *NewNode,
SmallVectorImpl<MDNode *> &Cycles, ValueToValueMapTy &VM,
RemapFlags Flags, ValueMapTypeRemapper *TypeMapper,
ValueMaterializer *Materializer) {
assert(OldNode->getNumOperands() == NewNode->getNumOperands() &&
"Expected nodes to match");
assert(OldNode->isResolved() && "Expected resolved node");
assert(!NewNode->isUniqued() && "Expected non-uniqued node");
// Map the node upfront so it's available for cyclic references.
mapToMetadata(VM, OldNode, NewNode);
bool AnyChanged = false;
for (unsigned I = 0, E = OldNode->getNumOperands(); I != E; ++I) {
Metadata *Old = OldNode->getOperand(I);
assert(NewNode->getOperand(I) == Old &&
"Expected old operands to already be in place");
Metadata *New = mapMetadataOp(OldNode->getOperand(I), Cycles, VM, Flags,
TypeMapper, Materializer);
if (Old != New) {
AnyChanged = true;
NewNode->replaceOperandWith(I, New);
}
}
return AnyChanged;
}
/// \brief Map a distinct MDNode.
///
/// Distinct nodes are not uniqued, so they must always recreated.
static Metadata *mapDistinctNode(const MDNode *Node,
SmallVectorImpl<MDNode *> &Cycles,
ValueToValueMapTy &VM, RemapFlags Flags,
ValueMapTypeRemapper *TypeMapper,
ValueMaterializer *Materializer) {
assert(Node->isDistinct() && "Expected distinct node");
MDNode *NewMD = MDNode::replaceWithDistinct(Node->clone());
remap(Node, NewMD, Cycles, VM, Flags, TypeMapper, Materializer);
// Track any cycles beneath this node.
for (Metadata *Op : NewMD->operands())
if (auto *Node = dyn_cast_or_null<MDNode>(Op))
if (!Node->isResolved())
Cycles.push_back(Node);
return NewMD;
}
/// \brief Map a uniqued MDNode.
///
/// Uniqued nodes may not need to be recreated (they may map to themselves).
static Metadata *mapUniquedNode(const MDNode *Node,
SmallVectorImpl<MDNode *> &Cycles,
ValueToValueMapTy &VM, RemapFlags Flags,
ValueMapTypeRemapper *TypeMapper,
ValueMaterializer *Materializer) {
assert(Node->isUniqued() && "Expected uniqued node");
// Create a temporary node upfront in case we have a metadata cycle.
auto ClonedMD = Node->clone();
if (!remap(Node, ClonedMD.get(), Cycles, VM, Flags, TypeMapper, Materializer))
// No operands changed, so use the identity mapping.
return mapToSelf(VM, Node);
// At least one operand has changed, so uniquify the cloned node.
return mapToMetadata(VM, Node,
MDNode::replaceWithUniqued(std::move(ClonedMD)));
}
static Metadata *MapMetadataImpl(const Metadata *MD,
SmallVectorImpl<MDNode *> &Cycles,
ValueToValueMapTy &VM, RemapFlags Flags,
ValueMapTypeRemapper *TypeMapper,
ValueMaterializer *Materializer) {
// If the value already exists in the map, use it.
if (Metadata *NewMD = VM.MD().lookup(MD).get())
return NewMD;
if (isa<MDString>(MD))
return mapToSelf(VM, MD);
if (isa<ConstantAsMetadata>(MD))
if ((Flags & RF_NoModuleLevelChanges))
return mapToSelf(VM, MD);
if (const auto *VMD = dyn_cast<ValueAsMetadata>(MD)) {
Value *MappedV =
MapValue(VMD->getValue(), VM, Flags, TypeMapper, Materializer);
if (VMD->getValue() == MappedV ||
(!MappedV && (Flags & RF_IgnoreMissingEntries)))
return mapToSelf(VM, MD);
// FIXME: This assert crashes during bootstrap, but I think it should be
// correct. For now, just match behaviour from before the metadata/value
// split.
//
// assert(MappedV && "Referenced metadata not in value map!");
if (MappedV)
return mapToMetadata(VM, MD, ValueAsMetadata::get(MappedV));
return nullptr;
}
// Note: this cast precedes the Flags check so we always get its associated
// assertion.
const MDNode *Node = cast<MDNode>(MD);
// If this is a module-level metadata and we know that nothing at the
// module level is changing, then use an identity mapping.
if (Flags & RF_NoModuleLevelChanges)
return mapToSelf(VM, MD);
// Require resolved nodes whenever metadata might be remapped.
assert(Node->isResolved() && "Unexpected unresolved node");
if (Node->isDistinct())
return mapDistinctNode(Node, Cycles, VM, Flags, TypeMapper, Materializer);
return mapUniquedNode(Node, Cycles, VM, Flags, TypeMapper, Materializer);
}
Metadata *llvm::MapMetadata(const Metadata *MD, ValueToValueMapTy &VM,
RemapFlags Flags, ValueMapTypeRemapper *TypeMapper,
ValueMaterializer *Materializer) {
SmallVector<MDNode *, 8> Cycles;
Metadata *NewMD =
MapMetadataImpl(MD, Cycles, VM, Flags, TypeMapper, Materializer);
// Resolve cycles underneath MD.
if (NewMD && NewMD != MD) {
if (auto *N = dyn_cast<MDNode>(NewMD))
if (!N->isResolved())
N->resolveCycles();
for (MDNode *N : Cycles)
if (!N->isResolved())
N->resolveCycles();
} else {
// Shouldn't get unresolved cycles if nothing was remapped.
assert(Cycles.empty() && "Expected no unresolved cycles");
}
return NewMD;
}
MDNode *llvm::MapMetadata(const MDNode *MD, ValueToValueMapTy &VM,
RemapFlags Flags, ValueMapTypeRemapper *TypeMapper,
ValueMaterializer *Materializer) {
return cast<MDNode>(MapMetadata(static_cast<const Metadata *>(MD), VM, Flags,
TypeMapper, Materializer));
}
/// RemapInstruction - Convert the instruction operands from referencing the
/// current values into those specified by VMap.
///
void llvm::RemapInstruction(Instruction *I, ValueToValueMapTy &VMap,
RemapFlags Flags, ValueMapTypeRemapper *TypeMapper,
ValueMaterializer *Materializer){
// Remap operands.
for (User::op_iterator op = I->op_begin(), E = I->op_end(); op != E; ++op) {
Value *V = MapValue(*op, VMap, Flags, TypeMapper, Materializer);
// If we aren't ignoring missing entries, assert that something happened.
if (V)
*op = V;
else
assert((Flags & RF_IgnoreMissingEntries) &&
"Referenced value not in value map!");
}
// Remap phi nodes' incoming blocks.
if (PHINode *PN = dyn_cast<PHINode>(I)) {
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
Value *V = MapValue(PN->getIncomingBlock(i), VMap, Flags);
// If we aren't ignoring missing entries, assert that something happened.
if (V)
PN->setIncomingBlock(i, cast<BasicBlock>(V));
else
assert((Flags & RF_IgnoreMissingEntries) &&
"Referenced block not in value map!");
}
}
// Remap attached metadata.
SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
I->getAllMetadata(MDs);
for (SmallVectorImpl<std::pair<unsigned, MDNode *>>::iterator
MI = MDs.begin(),
ME = MDs.end();
MI != ME; ++MI) {
MDNode *Old = MI->second;
MDNode *New = MapMetadata(Old, VMap, Flags, TypeMapper, Materializer);
if (New != Old)
I->setMetadata(MI->first, New);
}
if (!TypeMapper)
return;
// If the instruction's type is being remapped, do so now.
if (auto CS = CallSite(I)) {
SmallVector<Type *, 3> Tys;
FunctionType *FTy = CS.getFunctionType();
Tys.reserve(FTy->getNumParams());
for (Type *Ty : FTy->params())
Tys.push_back(TypeMapper->remapType(Ty));
CS.mutateFunctionType(FunctionType::get(
TypeMapper->remapType(I->getType()), Tys, FTy->isVarArg()));
return;
}
if (auto *AI = dyn_cast<AllocaInst>(I))
AI->setAllocatedType(TypeMapper->remapType(AI->getAllocatedType()));
if (auto *GEP = dyn_cast<GetElementPtrInst>(I)) {
GEP->setSourceElementType(
TypeMapper->remapType(GEP->getSourceElementType()));
GEP->setResultElementType(
TypeMapper->remapType(GEP->getResultElementType()));
}
I->mutateType(TypeMapper->remapType(I->getType()));
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/ASanStackFrameLayout.cpp | //===-- ASanStackFrameLayout.cpp - helper for AddressSanitizer ------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Definition of ComputeASanStackFrameLayout (see ASanStackFrameLayout.h).
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/ASanStackFrameLayout.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/MathExtras.h"
#include <algorithm>
// //
///////////////////////////////////////////////////////////////////////////////
namespace llvm {
// We sort the stack variables by alignment (largest first) to minimize
// unnecessary large gaps due to alignment.
// It is tempting to also sort variables by size so that larger variables
// have larger redzones at both ends. But reordering will make report analysis
// harder, especially when temporary unnamed variables are present.
// So, until we can provide more information (type, line number, etc)
// for the stack variables we avoid reordering them too much.
static inline bool CompareVars(const ASanStackVariableDescription &a,
const ASanStackVariableDescription &b) {
return a.Alignment > b.Alignment;
}
// We also force minimal alignment for all vars to kMinAlignment so that vars
// with e.g. alignment 1 and alignment 16 do not get reordered by CompareVars.
static const size_t kMinAlignment = 16;
// The larger the variable Size the larger is the redzone.
// The resulting frame size is a multiple of Alignment.
static size_t VarAndRedzoneSize(size_t Size, size_t Alignment) {
size_t Res = 0;
if (Size <= 4) Res = 16;
else if (Size <= 16) Res = 32;
else if (Size <= 128) Res = Size + 32;
else if (Size <= 512) Res = Size + 64;
else if (Size <= 4096) Res = Size + 128;
else Res = Size + 256;
return RoundUpToAlignment(Res, Alignment);
}
void
ComputeASanStackFrameLayout(SmallVectorImpl<ASanStackVariableDescription> &Vars,
size_t Granularity, size_t MinHeaderSize,
ASanStackFrameLayout *Layout) {
assert(Granularity >= 8 && Granularity <= 64 &&
(Granularity & (Granularity - 1)) == 0);
assert(MinHeaderSize >= 16 && (MinHeaderSize & (MinHeaderSize - 1)) == 0 &&
MinHeaderSize >= Granularity);
size_t NumVars = Vars.size();
assert(NumVars > 0);
for (size_t i = 0; i < NumVars; i++)
Vars[i].Alignment = std::max(Vars[i].Alignment, kMinAlignment);
std::stable_sort(Vars.begin(), Vars.end(), CompareVars);
SmallString<2048> StackDescriptionStorage;
raw_svector_ostream StackDescription(StackDescriptionStorage);
StackDescription << NumVars;
Layout->FrameAlignment = std::max(Granularity, Vars[0].Alignment);
SmallVector<uint8_t, 64> &SB(Layout->ShadowBytes);
SB.clear();
size_t Offset = std::max(std::max(MinHeaderSize, Granularity),
Vars[0].Alignment);
assert((Offset % Granularity) == 0);
SB.insert(SB.end(), Offset / Granularity, kAsanStackLeftRedzoneMagic);
for (size_t i = 0; i < NumVars; i++) {
bool IsLast = i == NumVars - 1;
size_t Alignment = std::max(Granularity, Vars[i].Alignment);
(void)Alignment; // Used only in asserts.
size_t Size = Vars[i].Size;
const char *Name = Vars[i].Name;
assert((Alignment & (Alignment - 1)) == 0);
assert(Layout->FrameAlignment >= Alignment);
assert((Offset % Alignment) == 0);
assert(Size > 0);
StackDescription << " " << Offset << " " << Size << " " << strlen(Name)
<< " " << Name;
size_t NextAlignment = IsLast ? Granularity
: std::max(Granularity, Vars[i + 1].Alignment);
size_t SizeWithRedzone = VarAndRedzoneSize(Vars[i].Size, NextAlignment);
SB.insert(SB.end(), Size / Granularity, 0);
if (Size % Granularity)
SB.insert(SB.end(), Size % Granularity);
SB.insert(SB.end(), (SizeWithRedzone - Size) / Granularity,
IsLast ? kAsanStackRightRedzoneMagic
: kAsanStackMidRedzoneMagic);
Vars[i].Offset = Offset;
Offset += SizeWithRedzone;
}
if (Offset % MinHeaderSize) {
size_t ExtraRedzone = MinHeaderSize - (Offset % MinHeaderSize);
SB.insert(SB.end(), ExtraRedzone / Granularity,
kAsanStackRightRedzoneMagic);
Offset += ExtraRedzone;
}
Layout->DescriptionString = StackDescription.str();
Layout->FrameSize = Offset;
assert((Layout->FrameSize % MinHeaderSize) == 0);
assert(Layout->FrameSize / Granularity == Layout->ShadowBytes.size());
}
} // llvm namespace
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/SimplifyInstructions.cpp | //===------ SimplifyInstructions.cpp - Remove redundant instructions ------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This is a utility pass used for testing the InstructionSimplify analysis.
// The analysis is applied to every instruction, and if it simplifies then the
// instruction is replaced by the simplification. If you are looking for a pass
// that performs serious instruction folding, use the instcombine pass instead.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Scalar.h"
#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Type.h"
#include "llvm/Pass.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Transforms/Utils/Local.h"
using namespace llvm;
#define DEBUG_TYPE "instsimplify"
STATISTIC(NumSimplified, "Number of redundant instructions removed");
namespace {
struct InstSimplifier : public FunctionPass {
static char ID; // Pass identification, replacement for typeid
InstSimplifier() : FunctionPass(ID) {
initializeInstSimplifierPass(*PassRegistry::getPassRegistry());
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.setPreservesCFG();
AU.addRequired<AssumptionCacheTracker>();
AU.addRequired<TargetLibraryInfoWrapperPass>();
}
/// runOnFunction - Remove instructions that simplify.
bool runOnFunction(Function &F) override {
const DominatorTreeWrapperPass *DTWP =
getAnalysisIfAvailable<DominatorTreeWrapperPass>();
const DominatorTree *DT = DTWP ? &DTWP->getDomTree() : nullptr;
const DataLayout &DL = F.getParent()->getDataLayout();
const TargetLibraryInfo *TLI =
&getAnalysis<TargetLibraryInfoWrapperPass>().getTLI();
AssumptionCache *AC =
&getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
SmallPtrSet<const Instruction*, 8> S1, S2, *ToSimplify = &S1, *Next = &S2;
bool Changed = false;
do {
for (BasicBlock *BB : depth_first(&F.getEntryBlock()))
// Here be subtlety: the iterator must be incremented before the loop
// body (not sure why), so a range-for loop won't work here.
for (BasicBlock::iterator BI = BB->begin(), BE = BB->end(); BI != BE;) {
Instruction *I = BI++;
// The first time through the loop ToSimplify is empty and we try to
// simplify all instructions. On later iterations ToSimplify is not
// empty and we only bother simplifying instructions that are in it.
if (!ToSimplify->empty() && !ToSimplify->count(I))
continue;
// Don't waste time simplifying unused instructions.
if (!I->use_empty())
if (Value *V = SimplifyInstruction(I, DL, TLI, DT, AC)) {
// Mark all uses for resimplification next time round the loop.
for (User *U : I->users())
Next->insert(cast<Instruction>(U));
I->replaceAllUsesWith(V);
++NumSimplified;
Changed = true;
}
bool res = RecursivelyDeleteTriviallyDeadInstructions(I, TLI);
if (res) {
// RecursivelyDeleteTriviallyDeadInstruction can remove
// more than one instruction, so simply incrementing the
// iterator does not work. When instructions get deleted
// re-iterate instead.
BI = BB->begin(); BE = BB->end();
Changed |= res;
}
}
// Place the list of instructions to simplify on the next loop iteration
// into ToSimplify.
std::swap(ToSimplify, Next);
Next->clear();
} while (!ToSimplify->empty());
return Changed;
}
};
}
char InstSimplifier::ID = 0;
INITIALIZE_PASS_BEGIN(InstSimplifier, "instsimplify",
"Remove redundant instructions", false, false)
INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)
INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
INITIALIZE_PASS_END(InstSimplifier, "instsimplify",
"Remove redundant instructions", false, false)
char &llvm::InstructionSimplifierID = InstSimplifier::ID;
// Public interface to the simplify instructions pass.
FunctionPass *llvm::createInstructionSimplifierPass() {
return new InstSimplifier();
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/MetaRenamer.cpp | //===- MetaRenamer.cpp - Rename everything with metasyntatic names --------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This pass renames everything with metasyntatic names. The intent is to use
// this pass after bugpoint reduction to conceal the nature of the original
// program.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/IPO.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/TypeFinder.h"
#include "llvm/Pass.h"
using namespace llvm;
namespace {
// This PRNG is from the ISO C spec. It is intentionally simple and
// unsuitable for cryptographic use. We're just looking for enough
// variety to surprise and delight users.
struct PRNG {
unsigned long next;
void srand(unsigned int seed) {
next = seed;
}
int rand() {
next = next * 1103515245 + 12345;
return (unsigned int)(next / 65536) % 32768;
}
};
struct MetaRenamer : public ModulePass {
static char ID; // Pass identification, replacement for typeid
MetaRenamer() : ModulePass(ID) {
initializeMetaRenamerPass(*PassRegistry::getPassRegistry());
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.setPreservesAll();
}
bool runOnModule(Module &M) override {
static const char *const metaNames[] = {
// See http://en.wikipedia.org/wiki/Metasyntactic_variable
"foo", "bar", "baz", "quux", "barney", "snork", "zot", "blam", "hoge",
"wibble", "wobble", "widget", "wombat", "ham", "eggs", "pluto", "spam"
};
// Seed our PRNG with simple additive sum of ModuleID. We're looking to
// simply avoid always having the same function names, and we need to
// remain deterministic.
unsigned int randSeed = 0;
for (std::string::const_iterator I = M.getModuleIdentifier().begin(),
E = M.getModuleIdentifier().end(); I != E; ++I)
randSeed += *I;
PRNG prng;
prng.srand(randSeed);
// Rename all aliases
for (Module::alias_iterator AI = M.alias_begin(), AE = M.alias_end();
AI != AE; ++AI) {
StringRef Name = AI->getName();
if (Name.startswith("llvm.") || (!Name.empty() && Name[0] == 1))
continue;
AI->setName("alias");
}
// Rename all global variables
for (Module::global_iterator GI = M.global_begin(), GE = M.global_end();
GI != GE; ++GI) {
StringRef Name = GI->getName();
if (Name.startswith("llvm.") || (!Name.empty() && Name[0] == 1))
continue;
GI->setName("global");
}
// Rename all struct types
TypeFinder StructTypes;
StructTypes.run(M, true);
for (unsigned i = 0, e = StructTypes.size(); i != e; ++i) {
StructType *STy = StructTypes[i];
if (STy->isLiteral() || STy->getName().empty()) continue;
SmallString<128> NameStorage;
STy->setName((Twine("struct.") + metaNames[prng.rand() %
array_lengthof(metaNames)]).toStringRef(NameStorage));
}
// Rename all functions
for (Module::iterator FI = M.begin(), FE = M.end();
FI != FE; ++FI) {
StringRef Name = FI->getName();
if (Name.startswith("llvm.") || (!Name.empty() && Name[0] == 1))
continue;
FI->setName(metaNames[prng.rand() % array_lengthof(metaNames)]);
runOnFunction(*FI);
}
return true;
}
bool runOnFunction(Function &F) {
for (Function::arg_iterator AI = F.arg_begin(), AE = F.arg_end();
AI != AE; ++AI)
if (!AI->getType()->isVoidTy())
AI->setName("arg");
for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) {
BB->setName("bb");
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
if (!I->getType()->isVoidTy())
I->setName("tmp");
}
return true;
}
};
}
char MetaRenamer::ID = 0;
INITIALIZE_PASS(MetaRenamer, "metarenamer",
"Assign new names to everything", false, false)
//===----------------------------------------------------------------------===//
//
// MetaRenamer - Rename everything with metasyntactic names.
//
ModulePass *llvm::createMetaRenamerPass() {
return new MetaRenamer();
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/LoopUtils.cpp | //===-- LoopUtils.cpp - Loop Utility functions -------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines common loop utility functions.
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/Support/Debug.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/ScalarEvolutionExpressions.h"
#include "llvm/IR/Module.h"
#include "llvm/Transforms/Utils/LoopUtils.h"
using namespace llvm;
using namespace llvm::PatternMatch;
#define DEBUG_TYPE "loop-utils"
bool RecurrenceDescriptor::areAllUsesIn(Instruction *I,
SmallPtrSetImpl<Instruction *> &Set) {
for (User::op_iterator Use = I->op_begin(), E = I->op_end(); Use != E; ++Use)
if (!Set.count(dyn_cast<Instruction>(*Use)))
return false;
return true;
}
bool RecurrenceDescriptor::AddReductionVar(PHINode *Phi, RecurrenceKind Kind,
Loop *TheLoop, bool HasFunNoNaNAttr,
RecurrenceDescriptor &RedDes) {
if (Phi->getNumIncomingValues() != 2)
return false;
// Reduction variables are only found in the loop header block.
if (Phi->getParent() != TheLoop->getHeader())
return false;
// Obtain the reduction start value from the value that comes from the loop
// preheader.
Value *RdxStart = Phi->getIncomingValueForBlock(TheLoop->getLoopPreheader());
// ExitInstruction is the single value which is used outside the loop.
// We only allow for a single reduction value to be used outside the loop.
// This includes users of the reduction, variables (which form a cycle
// which ends in the phi node).
Instruction *ExitInstruction = nullptr;
// Indicates that we found a reduction operation in our scan.
bool FoundReduxOp = false;
// We start with the PHI node and scan for all of the users of this
// instruction. All users must be instructions that can be used as reduction
// variables (such as ADD). We must have a single out-of-block user. The cycle
// must include the original PHI.
bool FoundStartPHI = false;
// To recognize min/max patterns formed by a icmp select sequence, we store
// the number of instruction we saw from the recognized min/max pattern,
// to make sure we only see exactly the two instructions.
unsigned NumCmpSelectPatternInst = 0;
InstDesc ReduxDesc(false, nullptr);
SmallPtrSet<Instruction *, 8> VisitedInsts;
SmallVector<Instruction *, 8> Worklist;
Worklist.push_back(Phi);
VisitedInsts.insert(Phi);
// A value in the reduction can be used:
// - By the reduction:
// - Reduction operation:
// - One use of reduction value (safe).
// - Multiple use of reduction value (not safe).
// - PHI:
// - All uses of the PHI must be the reduction (safe).
// - Otherwise, not safe.
// - By one instruction outside of the loop (safe).
// - By further instructions outside of the loop (not safe).
// - By an instruction that is not part of the reduction (not safe).
// This is either:
// * An instruction type other than PHI or the reduction operation.
// * A PHI in the header other than the initial PHI.
while (!Worklist.empty()) {
Instruction *Cur = Worklist.back();
Worklist.pop_back();
// No Users.
// If the instruction has no users then this is a broken chain and can't be
// a reduction variable.
if (Cur->use_empty())
return false;
bool IsAPhi = isa<PHINode>(Cur);
// A header PHI use other than the original PHI.
if (Cur != Phi && IsAPhi && Cur->getParent() == Phi->getParent())
return false;
// Reductions of instructions such as Div, and Sub is only possible if the
// LHS is the reduction variable.
if (!Cur->isCommutative() && !IsAPhi && !isa<SelectInst>(Cur) &&
!isa<ICmpInst>(Cur) && !isa<FCmpInst>(Cur) &&
!VisitedInsts.count(dyn_cast<Instruction>(Cur->getOperand(0))))
return false;
// Any reduction instruction must be of one of the allowed kinds.
ReduxDesc = isRecurrenceInstr(Cur, Kind, ReduxDesc, HasFunNoNaNAttr);
if (!ReduxDesc.isRecurrence())
return false;
// A reduction operation must only have one use of the reduction value.
if (!IsAPhi && Kind != RK_IntegerMinMax && Kind != RK_FloatMinMax &&
hasMultipleUsesOf(Cur, VisitedInsts))
return false;
// All inputs to a PHI node must be a reduction value.
if (IsAPhi && Cur != Phi && !areAllUsesIn(Cur, VisitedInsts))
return false;
if (Kind == RK_IntegerMinMax &&
(isa<ICmpInst>(Cur) || isa<SelectInst>(Cur)))
++NumCmpSelectPatternInst;
if (Kind == RK_FloatMinMax && (isa<FCmpInst>(Cur) || isa<SelectInst>(Cur)))
++NumCmpSelectPatternInst;
// Check whether we found a reduction operator.
FoundReduxOp |= !IsAPhi;
// Process users of current instruction. Push non-PHI nodes after PHI nodes
// onto the stack. This way we are going to have seen all inputs to PHI
// nodes once we get to them.
SmallVector<Instruction *, 8> NonPHIs;
SmallVector<Instruction *, 8> PHIs;
for (User *U : Cur->users()) {
Instruction *UI = cast<Instruction>(U);
// Check if we found the exit user.
BasicBlock *Parent = UI->getParent();
if (!TheLoop->contains(Parent)) {
// Exit if you find multiple outside users or if the header phi node is
// being used. In this case the user uses the value of the previous
// iteration, in which case we would loose "VF-1" iterations of the
// reduction operation if we vectorize.
if (ExitInstruction != nullptr || Cur == Phi)
return false;
// The instruction used by an outside user must be the last instruction
// before we feed back to the reduction phi. Otherwise, we loose VF-1
// operations on the value.
if (std::find(Phi->op_begin(), Phi->op_end(), Cur) == Phi->op_end())
return false;
ExitInstruction = Cur;
continue;
}
// Process instructions only once (termination). Each reduction cycle
// value must only be used once, except by phi nodes and min/max
// reductions which are represented as a cmp followed by a select.
InstDesc IgnoredVal(false, nullptr);
if (VisitedInsts.insert(UI).second) {
if (isa<PHINode>(UI))
PHIs.push_back(UI);
else
NonPHIs.push_back(UI);
} else if (!isa<PHINode>(UI) &&
((!isa<FCmpInst>(UI) && !isa<ICmpInst>(UI) &&
!isa<SelectInst>(UI)) ||
!isMinMaxSelectCmpPattern(UI, IgnoredVal).isRecurrence()))
return false;
// Remember that we completed the cycle.
if (UI == Phi)
FoundStartPHI = true;
}
Worklist.append(PHIs.begin(), PHIs.end());
Worklist.append(NonPHIs.begin(), NonPHIs.end());
}
// This means we have seen one but not the other instruction of the
// pattern or more than just a select and cmp.
if ((Kind == RK_IntegerMinMax || Kind == RK_FloatMinMax) &&
NumCmpSelectPatternInst != 2)
return false;
if (!FoundStartPHI || !FoundReduxOp || !ExitInstruction)
return false;
// We found a reduction var if we have reached the original phi node and we
// only have a single instruction with out-of-loop users.
// The ExitInstruction(Instruction which is allowed to have out-of-loop users)
// is saved as part of the RecurrenceDescriptor.
// Save the description of this reduction variable.
RecurrenceDescriptor RD(RdxStart, ExitInstruction, Kind,
ReduxDesc.getMinMaxKind());
RedDes = RD;
return true;
}
/// Returns true if the instruction is a Select(ICmp(X, Y), X, Y) instruction
/// pattern corresponding to a min(X, Y) or max(X, Y).
RecurrenceDescriptor::InstDesc
RecurrenceDescriptor::isMinMaxSelectCmpPattern(Instruction *I, InstDesc &Prev) {
assert((isa<ICmpInst>(I) || isa<FCmpInst>(I) || isa<SelectInst>(I)) &&
"Expect a select instruction");
Instruction *Cmp = nullptr;
SelectInst *Select = nullptr;
// We must handle the select(cmp()) as a single instruction. Advance to the
// select.
if ((Cmp = dyn_cast<ICmpInst>(I)) || (Cmp = dyn_cast<FCmpInst>(I))) {
if (!Cmp->hasOneUse() || !(Select = dyn_cast<SelectInst>(*I->user_begin())))
return InstDesc(false, I);
return InstDesc(Select, Prev.getMinMaxKind());
}
// Only handle single use cases for now.
if (!(Select = dyn_cast<SelectInst>(I)))
return InstDesc(false, I);
if (!(Cmp = dyn_cast<ICmpInst>(I->getOperand(0))) &&
!(Cmp = dyn_cast<FCmpInst>(I->getOperand(0))))
return InstDesc(false, I);
if (!Cmp->hasOneUse())
return InstDesc(false, I);
Value *CmpLeft;
Value *CmpRight;
// Look for a min/max pattern.
if (m_UMin(m_Value(CmpLeft), m_Value(CmpRight)).match(Select))
return InstDesc(Select, MRK_UIntMin);
else if (m_UMax(m_Value(CmpLeft), m_Value(CmpRight)).match(Select))
return InstDesc(Select, MRK_UIntMax);
else if (m_SMax(m_Value(CmpLeft), m_Value(CmpRight)).match(Select))
return InstDesc(Select, MRK_SIntMax);
else if (m_SMin(m_Value(CmpLeft), m_Value(CmpRight)).match(Select))
return InstDesc(Select, MRK_SIntMin);
else if (m_OrdFMin(m_Value(CmpLeft), m_Value(CmpRight)).match(Select))
return InstDesc(Select, MRK_FloatMin);
else if (m_OrdFMax(m_Value(CmpLeft), m_Value(CmpRight)).match(Select))
return InstDesc(Select, MRK_FloatMax);
else if (m_UnordFMin(m_Value(CmpLeft), m_Value(CmpRight)).match(Select))
return InstDesc(Select, MRK_FloatMin);
else if (m_UnordFMax(m_Value(CmpLeft), m_Value(CmpRight)).match(Select))
return InstDesc(Select, MRK_FloatMax);
return InstDesc(false, I);
}
RecurrenceDescriptor::InstDesc
RecurrenceDescriptor::isRecurrenceInstr(Instruction *I, RecurrenceKind Kind,
InstDesc &Prev, bool HasFunNoNaNAttr) {
bool FP = I->getType()->isFloatingPointTy();
bool FastMath = FP && I->hasUnsafeAlgebra();
switch (I->getOpcode()) {
default:
return InstDesc(false, I);
case Instruction::PHI:
if (FP &&
(Kind != RK_FloatMult && Kind != RK_FloatAdd && Kind != RK_FloatMinMax))
return InstDesc(false, I);
return InstDesc(I, Prev.getMinMaxKind());
case Instruction::Sub:
case Instruction::Add:
return InstDesc(Kind == RK_IntegerAdd, I);
case Instruction::Mul:
return InstDesc(Kind == RK_IntegerMult, I);
case Instruction::And:
return InstDesc(Kind == RK_IntegerAnd, I);
case Instruction::Or:
return InstDesc(Kind == RK_IntegerOr, I);
case Instruction::Xor:
return InstDesc(Kind == RK_IntegerXor, I);
case Instruction::FMul:
return InstDesc(Kind == RK_FloatMult && FastMath, I);
case Instruction::FSub:
case Instruction::FAdd:
return InstDesc(Kind == RK_FloatAdd && FastMath, I);
case Instruction::FCmp:
case Instruction::ICmp:
case Instruction::Select:
if (Kind != RK_IntegerMinMax &&
(!HasFunNoNaNAttr || Kind != RK_FloatMinMax))
return InstDesc(false, I);
return isMinMaxSelectCmpPattern(I, Prev);
}
}
bool RecurrenceDescriptor::hasMultipleUsesOf(
Instruction *I, SmallPtrSetImpl<Instruction *> &Insts) {
unsigned NumUses = 0;
for (User::op_iterator Use = I->op_begin(), E = I->op_end(); Use != E;
++Use) {
if (Insts.count(dyn_cast<Instruction>(*Use)))
++NumUses;
if (NumUses > 1)
return true;
}
return false;
}
bool RecurrenceDescriptor::isReductionPHI(PHINode *Phi, Loop *TheLoop,
RecurrenceDescriptor &RedDes) {
bool HasFunNoNaNAttr = false;
BasicBlock *Header = TheLoop->getHeader();
Function &F = *Header->getParent();
if (F.hasFnAttribute("no-nans-fp-math"))
HasFunNoNaNAttr =
F.getFnAttribute("no-nans-fp-math").getValueAsString() == "true";
if (AddReductionVar(Phi, RK_IntegerAdd, TheLoop, HasFunNoNaNAttr, RedDes)) {
DEBUG(dbgs() << "Found an ADD reduction PHI." << *Phi << "\n");
return true;
}
if (AddReductionVar(Phi, RK_IntegerMult, TheLoop, HasFunNoNaNAttr, RedDes)) {
DEBUG(dbgs() << "Found a MUL reduction PHI." << *Phi << "\n");
return true;
}
if (AddReductionVar(Phi, RK_IntegerOr, TheLoop, HasFunNoNaNAttr, RedDes)) {
DEBUG(dbgs() << "Found an OR reduction PHI." << *Phi << "\n");
return true;
}
if (AddReductionVar(Phi, RK_IntegerAnd, TheLoop, HasFunNoNaNAttr, RedDes)) {
DEBUG(dbgs() << "Found an AND reduction PHI." << *Phi << "\n");
return true;
}
if (AddReductionVar(Phi, RK_IntegerXor, TheLoop, HasFunNoNaNAttr, RedDes)) {
DEBUG(dbgs() << "Found a XOR reduction PHI." << *Phi << "\n");
return true;
}
if (AddReductionVar(Phi, RK_IntegerMinMax, TheLoop, HasFunNoNaNAttr,
RedDes)) {
DEBUG(dbgs() << "Found a MINMAX reduction PHI." << *Phi << "\n");
return true;
}
if (AddReductionVar(Phi, RK_FloatMult, TheLoop, HasFunNoNaNAttr, RedDes)) {
DEBUG(dbgs() << "Found an FMult reduction PHI." << *Phi << "\n");
return true;
}
if (AddReductionVar(Phi, RK_FloatAdd, TheLoop, HasFunNoNaNAttr, RedDes)) {
DEBUG(dbgs() << "Found an FAdd reduction PHI." << *Phi << "\n");
return true;
}
if (AddReductionVar(Phi, RK_FloatMinMax, TheLoop, HasFunNoNaNAttr, RedDes)) {
DEBUG(dbgs() << "Found an float MINMAX reduction PHI." << *Phi << "\n");
return true;
}
// Not a reduction of known type.
return false;
}
/// This function returns the identity element (or neutral element) for
/// the operation K.
Constant *RecurrenceDescriptor::getRecurrenceIdentity(RecurrenceKind K,
Type *Tp) {
switch (K) {
case RK_IntegerXor:
case RK_IntegerAdd:
case RK_IntegerOr:
// Adding, Xoring, Oring zero to a number does not change it.
return ConstantInt::get(Tp, 0);
case RK_IntegerMult:
// Multiplying a number by 1 does not change it.
return ConstantInt::get(Tp, 1);
case RK_IntegerAnd:
// AND-ing a number with an all-1 value does not change it.
return ConstantInt::get(Tp, -1, true);
case RK_FloatMult:
// Multiplying a number by 1 does not change it.
return ConstantFP::get(Tp, 1.0L);
case RK_FloatAdd:
// Adding zero to a number does not change it.
return ConstantFP::get(Tp, 0.0L);
default:
llvm_unreachable("Unknown recurrence kind");
}
}
/// This function translates the recurrence kind to an LLVM binary operator.
unsigned RecurrenceDescriptor::getRecurrenceBinOp(RecurrenceKind Kind) {
switch (Kind) {
case RK_IntegerAdd:
return Instruction::Add;
case RK_IntegerMult:
return Instruction::Mul;
case RK_IntegerOr:
return Instruction::Or;
case RK_IntegerAnd:
return Instruction::And;
case RK_IntegerXor:
return Instruction::Xor;
case RK_FloatMult:
return Instruction::FMul;
case RK_FloatAdd:
return Instruction::FAdd;
case RK_IntegerMinMax:
return Instruction::ICmp;
case RK_FloatMinMax:
return Instruction::FCmp;
default:
llvm_unreachable("Unknown recurrence operation");
}
}
Value *RecurrenceDescriptor::createMinMaxOp(IRBuilder<> &Builder,
MinMaxRecurrenceKind RK,
Value *Left, Value *Right) {
CmpInst::Predicate P = CmpInst::ICMP_NE;
switch (RK) {
default:
llvm_unreachable("Unknown min/max recurrence kind");
case MRK_UIntMin:
P = CmpInst::ICMP_ULT;
break;
case MRK_UIntMax:
P = CmpInst::ICMP_UGT;
break;
case MRK_SIntMin:
P = CmpInst::ICMP_SLT;
break;
case MRK_SIntMax:
P = CmpInst::ICMP_SGT;
break;
case MRK_FloatMin:
P = CmpInst::FCMP_OLT;
break;
case MRK_FloatMax:
P = CmpInst::FCMP_OGT;
break;
}
Value *Cmp;
if (RK == MRK_FloatMin || RK == MRK_FloatMax)
Cmp = Builder.CreateFCmp(P, Left, Right, "rdx.minmax.cmp");
else
Cmp = Builder.CreateICmp(P, Left, Right, "rdx.minmax.cmp");
Value *Select = Builder.CreateSelect(Cmp, Left, Right, "rdx.minmax.select");
return Select;
}
bool llvm::isInductionPHI(PHINode *Phi, ScalarEvolution *SE,
ConstantInt *&StepValue) {
Type *PhiTy = Phi->getType();
// We only handle integer and pointer inductions variables.
if (!PhiTy->isIntegerTy() && !PhiTy->isPointerTy())
return false;
// Check that the PHI is consecutive.
const SCEV *PhiScev = SE->getSCEV(Phi);
const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(PhiScev);
if (!AR) {
DEBUG(dbgs() << "LV: PHI is not a poly recurrence.\n");
return false;
}
const SCEV *Step = AR->getStepRecurrence(*SE);
// Calculate the pointer stride and check if it is consecutive.
const SCEVConstant *C = dyn_cast<SCEVConstant>(Step);
if (!C)
return false;
ConstantInt *CV = C->getValue();
if (PhiTy->isIntegerTy()) {
StepValue = CV;
return true;
}
assert(PhiTy->isPointerTy() && "The PHI must be a pointer");
Type *PointerElementType = PhiTy->getPointerElementType();
// The pointer stride cannot be determined if the pointer element type is not
// sized.
if (!PointerElementType->isSized())
return false;
const DataLayout &DL = Phi->getModule()->getDataLayout();
int64_t Size = static_cast<int64_t>(DL.getTypeAllocSize(PointerElementType));
if (!Size)
return false;
int64_t CVSize = CV->getSExtValue();
if (CVSize % Size)
return false;
StepValue = ConstantInt::getSigned(CV->getType(), CVSize / Size);
return true;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/SimplifyCFG.cpp | //===- SimplifyCFG.cpp - Code to perform CFG simplification ---------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Peephole optimize the CFG.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/ConstantRange.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/NoFolder.h"
#include "llvm/IR/Operator.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/IR/Type.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/ValueMapper.h"
#include <algorithm>
#include <map>
#include <set>
#include "dxc/DXIL/DxilMetadataHelper.h" // HLSL Change - control flow hint.
using namespace llvm;
using namespace PatternMatch;
#define DEBUG_TYPE "simplifycfg"
// Chosen as 2 so as to be cheap, but still to have enough power to fold
// a select, so the "clamp" idiom (of a min followed by a max) will be caught.
// To catch this, we need to fold a compare and a select, hence '2' being the
// minimum reasonable default.
#if 0 // HLSL Change Starts - option pending
static cl::opt<unsigned>
PHINodeFoldingThreshold("phi-node-folding-threshold", cl::Hidden, cl::init(2),
cl::desc("Control the amount of phi node folding to perform (default = 2)"));
static cl::opt<bool>
DupRet("simplifycfg-dup-ret", cl::Hidden, cl::init(false),
cl::desc("Duplicate return instructions into unconditional branches"));
static cl::opt<bool>
SinkCommon("simplifycfg-sink-common", cl::Hidden, cl::init(true),
cl::desc("Sink common instructions down to the end block"));
static cl::opt<bool> HoistCondStores(
"simplifycfg-hoist-cond-stores", cl::Hidden, cl::init(true),
cl::desc("Hoist conditional stores if an unconditional store precedes"));
#else
static const unsigned PHINodeFoldingThreshold = 2;
static const bool DupRet = false;
static const bool SinkCommon = true;
static const bool HoistCondStores = true;
#endif // HLSL Change Ends
STATISTIC(NumBitMaps, "Number of switch instructions turned into bitmaps");
STATISTIC(NumLinearMaps, "Number of switch instructions turned into linear mapping");
STATISTIC(NumLookupTables, "Number of switch instructions turned into lookup tables");
STATISTIC(NumLookupTablesHoles, "Number of switch instructions turned into lookup tables (holes checked)");
STATISTIC(NumTableCmpReuses, "Number of reused switch table lookup compares");
STATISTIC(NumSinkCommons, "Number of common instructions sunk down to the end block");
STATISTIC(NumSpeculations, "Number of speculative executed instructions");
namespace {
// The first field contains the value that the switch produces when a certain
// case group is selected, and the second field is a vector containing the cases
// composing the case group.
typedef SmallVector<std::pair<Constant *, SmallVector<ConstantInt *, 4>>, 2>
SwitchCaseResultVectorTy;
// The first field contains the phi node that generates a result of the switch
// and the second field contains the value generated for a certain case in the switch
// for that PHI.
typedef SmallVector<std::pair<PHINode *, Constant *>, 4> SwitchCaseResultsTy;
/// ValueEqualityComparisonCase - Represents a case of a switch.
struct ValueEqualityComparisonCase {
ConstantInt *Value;
BasicBlock *Dest;
ValueEqualityComparisonCase(ConstantInt *Value, BasicBlock *Dest)
: Value(Value), Dest(Dest) {}
bool operator<(ValueEqualityComparisonCase RHS) const {
// Comparing pointers is ok as we only rely on the order for uniquing.
return Value < RHS.Value;
}
bool operator==(BasicBlock *RHSDest) const { return Dest == RHSDest; }
};
class SimplifyCFGOpt {
const TargetTransformInfo &TTI;
const DataLayout &DL;
unsigned BonusInstThreshold;
AssumptionCache *AC;
Value *isValueEqualityComparison(TerminatorInst *TI);
BasicBlock *GetValueEqualityComparisonCases(TerminatorInst *TI,
std::vector<ValueEqualityComparisonCase> &Cases);
bool SimplifyEqualityComparisonWithOnlyPredecessor(TerminatorInst *TI,
BasicBlock *Pred,
IRBuilder<> &Builder);
bool FoldValueComparisonIntoPredecessors(TerminatorInst *TI,
IRBuilder<> &Builder);
bool SimplifyReturn(ReturnInst *RI, IRBuilder<> &Builder);
bool SimplifyResume(ResumeInst *RI, IRBuilder<> &Builder);
bool SimplifyUnreachable(UnreachableInst *UI);
bool SimplifySwitch(SwitchInst *SI, IRBuilder<> &Builder);
bool SimplifyIndirectBr(IndirectBrInst *IBI);
bool SimplifyUncondBranch(BranchInst *BI, IRBuilder <> &Builder);
bool SimplifyCondBranch(BranchInst *BI, IRBuilder <>&Builder);
public:
SimplifyCFGOpt(const TargetTransformInfo &TTI, const DataLayout &DL,
unsigned BonusInstThreshold, AssumptionCache *AC)
: TTI(TTI), DL(DL), BonusInstThreshold(BonusInstThreshold), AC(AC) {}
bool run(BasicBlock *BB);
};
}
/// Return true if it is safe to merge these two
/// terminator instructions together.
static bool SafeToMergeTerminators(TerminatorInst *SI1, TerminatorInst *SI2) {
if (SI1 == SI2) return false; // Can't merge with self!
// It is not safe to merge these two switch instructions if they have a common
// successor, and if that successor has a PHI node, and if *that* PHI node has
// conflicting incoming values from the two switch blocks.
BasicBlock *SI1BB = SI1->getParent();
BasicBlock *SI2BB = SI2->getParent();
SmallPtrSet<BasicBlock*, 16> SI1Succs(succ_begin(SI1BB), succ_end(SI1BB));
for (succ_iterator I = succ_begin(SI2BB), E = succ_end(SI2BB); I != E; ++I)
if (SI1Succs.count(*I))
for (BasicBlock::iterator BBI = (*I)->begin();
isa<PHINode>(BBI); ++BBI) {
PHINode *PN = cast<PHINode>(BBI);
if (PN->getIncomingValueForBlock(SI1BB) !=
PN->getIncomingValueForBlock(SI2BB))
return false;
}
return true;
}
/// Return true if it is safe and profitable to merge these two terminator
/// instructions together, where SI1 is an unconditional branch. PhiNodes will
/// store all PHI nodes in common successors.
static bool isProfitableToFoldUnconditional(BranchInst *SI1,
BranchInst *SI2,
Instruction *Cond,
SmallVectorImpl<PHINode*> &PhiNodes) {
if (SI1 == SI2) return false; // Can't merge with self!
assert(SI1->isUnconditional() && SI2->isConditional());
// We fold the unconditional branch if we can easily update all PHI nodes in
// common successors:
// 1> We have a constant incoming value for the conditional branch;
// 2> We have "Cond" as the incoming value for the unconditional branch;
// 3> SI2->getCondition() and Cond have same operands.
CmpInst *Ci2 = dyn_cast<CmpInst>(SI2->getCondition());
if (!Ci2) return false;
if (!(Cond->getOperand(0) == Ci2->getOperand(0) &&
Cond->getOperand(1) == Ci2->getOperand(1)) &&
!(Cond->getOperand(0) == Ci2->getOperand(1) &&
Cond->getOperand(1) == Ci2->getOperand(0)))
return false;
BasicBlock *SI1BB = SI1->getParent();
BasicBlock *SI2BB = SI2->getParent();
SmallPtrSet<BasicBlock*, 16> SI1Succs(succ_begin(SI1BB), succ_end(SI1BB));
for (succ_iterator I = succ_begin(SI2BB), E = succ_end(SI2BB); I != E; ++I)
if (SI1Succs.count(*I))
for (BasicBlock::iterator BBI = (*I)->begin();
isa<PHINode>(BBI); ++BBI) {
PHINode *PN = cast<PHINode>(BBI);
if (PN->getIncomingValueForBlock(SI1BB) != Cond ||
!isa<ConstantInt>(PN->getIncomingValueForBlock(SI2BB)))
return false;
PhiNodes.push_back(PN);
}
return true;
}
/// Update PHI nodes in Succ to indicate that there will now be entries in it
/// from the 'NewPred' block. The values that will be flowing into the PHI nodes
/// will be the same as those coming in from ExistPred, an existing predecessor
/// of Succ.
static void AddPredecessorToBlock(BasicBlock *Succ, BasicBlock *NewPred,
BasicBlock *ExistPred) {
if (!isa<PHINode>(Succ->begin())) return; // Quick exit if nothing to do
PHINode *PN;
for (BasicBlock::iterator I = Succ->begin();
(PN = dyn_cast<PHINode>(I)); ++I)
PN->addIncoming(PN->getIncomingValueForBlock(ExistPred), NewPred);
}
/// Compute an abstract "cost" of speculating the given instruction,
/// which is assumed to be safe to speculate. TCC_Free means cheap,
/// TCC_Basic means less cheap, and TCC_Expensive means prohibitively
/// expensive.
static unsigned ComputeSpeculationCost(const User *I,
const TargetTransformInfo &TTI) {
assert(isSafeToSpeculativelyExecute(I) &&
"Instruction is not safe to speculatively execute!");
return TTI.getUserCost(I);
}
/// If we have a merge point of an "if condition" as accepted above,
/// return true if the specified value dominates the block. We
/// don't handle the true generality of domination here, just a special case
/// which works well enough for us.
///
/// If AggressiveInsts is non-null, and if V does not dominate BB, we check to
/// see if V (which must be an instruction) and its recursive operands
/// that do not dominate BB have a combined cost lower than CostRemaining and
/// are non-trapping. If both are true, the instruction is inserted into the
/// set and true is returned.
///
/// The cost for most non-trapping instructions is defined as 1 except for
/// Select whose cost is 2.
///
/// After this function returns, CostRemaining is decreased by the cost of
/// V plus its non-dominating operands. If that cost is greater than
/// CostRemaining, false is returned and CostRemaining is undefined.
static bool DominatesMergePoint(Value *V, BasicBlock *BB,
SmallPtrSetImpl<Instruction*> *AggressiveInsts,
unsigned &CostRemaining,
const TargetTransformInfo &TTI) {
Instruction *I = dyn_cast<Instruction>(V);
if (!I) {
// Non-instructions all dominate instructions, but not all constantexprs
// can be executed unconditionally.
if (ConstantExpr *C = dyn_cast<ConstantExpr>(V))
if (C->canTrap())
return false;
return true;
}
BasicBlock *PBB = I->getParent();
// We don't want to allow weird loops that might have the "if condition" in
// the bottom of this block.
if (PBB == BB) return false;
// If this instruction is defined in a block that contains an unconditional
// branch to BB, then it must be in the 'conditional' part of the "if
// statement". If not, it definitely dominates the region.
BranchInst *BI = dyn_cast<BranchInst>(PBB->getTerminator());
if (!BI || BI->isConditional() || BI->getSuccessor(0) != BB)
return true;
// If we aren't allowing aggressive promotion anymore, then don't consider
// instructions in the 'if region'.
if (!AggressiveInsts) return false;
// If we have seen this instruction before, don't count it again.
if (AggressiveInsts->count(I)) return true;
// Okay, it looks like the instruction IS in the "condition". Check to
// see if it's a cheap instruction to unconditionally compute, and if it
// only uses stuff defined outside of the condition. If so, hoist it out.
if (!isSafeToSpeculativelyExecute(I))
return false;
unsigned Cost = ComputeSpeculationCost(I, TTI);
if (Cost > CostRemaining)
return false;
CostRemaining -= Cost;
// Okay, we can only really hoist these out if their operands do
// not take us over the cost threshold.
for (User::op_iterator i = I->op_begin(), e = I->op_end(); i != e; ++i)
if (!DominatesMergePoint(*i, BB, AggressiveInsts, CostRemaining, TTI))
return false;
// Okay, it's safe to do this! Remember this instruction.
AggressiveInsts->insert(I);
return true;
}
/// Extract ConstantInt from value, looking through IntToPtr
/// and PointerNullValue. Return NULL if value is not a constant int.
static ConstantInt *GetConstantInt(Value *V, const DataLayout &DL) {
// Normal constant int.
ConstantInt *CI = dyn_cast<ConstantInt>(V);
if (CI || !isa<Constant>(V) || !V->getType()->isPointerTy())
return CI;
// This is some kind of pointer constant. Turn it into a pointer-sized
// ConstantInt if possible.
IntegerType *PtrTy = cast<IntegerType>(DL.getIntPtrType(V->getType()));
// Null pointer means 0, see SelectionDAGBuilder::getValue(const Value*).
if (isa<ConstantPointerNull>(V))
return ConstantInt::get(PtrTy, 0);
// IntToPtr const int.
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
if (CE->getOpcode() == Instruction::IntToPtr)
if (ConstantInt *CI = dyn_cast<ConstantInt>(CE->getOperand(0))) {
// The constant is very likely to have the right type already.
if (CI->getType() == PtrTy)
return CI;
else
return cast<ConstantInt>
(ConstantExpr::getIntegerCast(CI, PtrTy, /*isSigned=*/false));
}
return nullptr;
}
namespace {
/// Given a chain of or (||) or and (&&) comparison of a value against a
/// constant, this will try to recover the information required for a switch
/// structure.
/// It will depth-first traverse the chain of comparison, seeking for patterns
/// like %a == 12 or %a < 4 and combine them to produce a set of integer
/// representing the different cases for the switch.
/// Note that if the chain is composed of '||' it will build the set of elements
/// that matches the comparisons (i.e. any of this value validate the chain)
/// while for a chain of '&&' it will build the set elements that make the test
/// fail.
struct ConstantComparesGatherer {
const DataLayout &DL;
Value *CompValue; /// Value found for the switch comparison
Value *Extra; /// Extra clause to be checked before the switch
SmallVector<ConstantInt *, 8> Vals; /// Set of integers to match in switch
unsigned UsedICmps; /// Number of comparisons matched in the and/or chain
/// Construct and compute the result for the comparison instruction Cond
ConstantComparesGatherer(Instruction *Cond, const DataLayout &DL)
: DL(DL), CompValue(nullptr), Extra(nullptr), UsedICmps(0) {
gather(Cond);
}
/// Prevent copy
ConstantComparesGatherer(const ConstantComparesGatherer &) = delete;
ConstantComparesGatherer &
operator=(const ConstantComparesGatherer &) = delete;
private:
/// Try to set the current value used for the comparison, it succeeds only if
/// it wasn't set before or if the new value is the same as the old one
bool setValueOnce(Value *NewVal) {
if(CompValue && CompValue != NewVal) return false;
CompValue = NewVal;
return (CompValue != nullptr);
}
/// Try to match Instruction "I" as a comparison against a constant and
/// populates the array Vals with the set of values that match (or do not
/// match depending on isEQ).
/// Return false on failure. On success, the Value the comparison matched
/// against is placed in CompValue.
/// If CompValue is already set, the function is expected to fail if a match
/// is found but the value compared to is different.
bool matchInstruction(Instruction *I, bool isEQ) {
// If this is an icmp against a constant, handle this as one of the cases.
ICmpInst *ICI;
ConstantInt *C;
if (!((ICI = dyn_cast<ICmpInst>(I)) &&
(C = GetConstantInt(I->getOperand(1), DL)))) {
return false;
}
Value *RHSVal;
ConstantInt *RHSC;
// Pattern match a special case
// (x & ~2^x) == y --> x == y || x == y|2^x
// This undoes a transformation done by instcombine to fuse 2 compares.
if (ICI->getPredicate() == (isEQ ? ICmpInst::ICMP_EQ:ICmpInst::ICMP_NE)) {
if (match(ICI->getOperand(0),
m_And(m_Value(RHSVal), m_ConstantInt(RHSC)))) {
APInt Not = ~RHSC->getValue();
if (Not.isPowerOf2()) {
// If we already have a value for the switch, it has to match!
if(!setValueOnce(RHSVal))
return false;
Vals.push_back(C);
Vals.push_back(ConstantInt::get(C->getContext(),
C->getValue() | Not));
UsedICmps++;
return true;
}
}
// If we already have a value for the switch, it has to match!
if(!setValueOnce(ICI->getOperand(0)))
return false;
UsedICmps++;
Vals.push_back(C);
return ICI->getOperand(0);
}
// If we have "x ult 3", for example, then we can add 0,1,2 to the set.
ConstantRange Span = ConstantRange::makeAllowedICmpRegion(
ICI->getPredicate(), C->getValue());
// Shift the range if the compare is fed by an add. This is the range
// compare idiom as emitted by instcombine.
Value *CandidateVal = I->getOperand(0);
if(match(I->getOperand(0), m_Add(m_Value(RHSVal), m_ConstantInt(RHSC)))) {
Span = Span.subtract(RHSC->getValue());
CandidateVal = RHSVal;
}
// If this is an and/!= check, then we are looking to build the set of
// value that *don't* pass the and chain. I.e. to turn "x ugt 2" into
// x != 0 && x != 1.
if (!isEQ)
Span = Span.inverse();
// If there are a ton of values, we don't want to make a ginormous switch.
if (Span.getSetSize().ugt(8) || Span.isEmptySet()) {
return false;
}
// If we already have a value for the switch, it has to match!
if(!setValueOnce(CandidateVal))
return false;
// Add all values from the range to the set
for (APInt Tmp = Span.getLower(); Tmp != Span.getUpper(); ++Tmp)
Vals.push_back(ConstantInt::get(I->getContext(), Tmp));
UsedICmps++;
return true;
}
/// Given a potentially 'or'd or 'and'd together collection of icmp
/// eq/ne/lt/gt instructions that compare a value against a constant, extract
/// the value being compared, and stick the list constants into the Vals
/// vector.
/// One "Extra" case is allowed to differ from the other.
void gather(Value *V) {
Instruction *I = dyn_cast<Instruction>(V);
bool isEQ = (I->getOpcode() == Instruction::Or);
// Keep a stack (SmallVector for efficiency) for depth-first traversal
SmallVector<Value *, 8> DFT;
// Initialize
DFT.push_back(V);
while(!DFT.empty()) {
V = DFT.pop_back_val();
if (Instruction *I = dyn_cast<Instruction>(V)) {
// If it is a || (or && depending on isEQ), process the operands.
if (I->getOpcode() == (isEQ ? Instruction::Or : Instruction::And)) {
DFT.push_back(I->getOperand(1));
DFT.push_back(I->getOperand(0));
continue;
}
// Try to match the current instruction
if (matchInstruction(I, isEQ))
// Match succeed, continue the loop
continue;
}
// One element of the sequence of || (or &&) could not be match as a
// comparison against the same value as the others.
// We allow only one "Extra" case to be checked before the switch
if (!Extra) {
Extra = V;
continue;
}
// Failed to parse a proper sequence, abort now
CompValue = nullptr;
break;
}
}
};
}
static void EraseTerminatorInstAndDCECond(TerminatorInst *TI) {
Instruction *Cond = nullptr;
if (SwitchInst *SI = dyn_cast<SwitchInst>(TI)) {
Cond = dyn_cast<Instruction>(SI->getCondition());
} else if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
if (BI->isConditional())
Cond = dyn_cast<Instruction>(BI->getCondition());
} else if (IndirectBrInst *IBI = dyn_cast<IndirectBrInst>(TI)) {
Cond = dyn_cast<Instruction>(IBI->getAddress());
}
TI->eraseFromParent();
if (Cond) RecursivelyDeleteTriviallyDeadInstructions(Cond);
}
/// Return true if the specified terminator checks
/// to see if a value is equal to constant integer value.
Value *SimplifyCFGOpt::isValueEqualityComparison(TerminatorInst *TI) {
Value *CV = nullptr;
if (SwitchInst *SI = dyn_cast<SwitchInst>(TI)) {
// Do not permit merging of large switch instructions into their
// predecessors unless there is only one predecessor.
if (SI->getNumSuccessors()*std::distance(pred_begin(SI->getParent()),
pred_end(SI->getParent())) <= 128)
CV = SI->getCondition();
} else if (BranchInst *BI = dyn_cast<BranchInst>(TI))
if (BI->isConditional() && BI->getCondition()->hasOneUse())
if (ICmpInst *ICI = dyn_cast<ICmpInst>(BI->getCondition())) {
if (ICI->isEquality() && GetConstantInt(ICI->getOperand(1), DL))
CV = ICI->getOperand(0);
}
// Unwrap any lossless ptrtoint cast.
if (CV) {
if (PtrToIntInst *PTII = dyn_cast<PtrToIntInst>(CV)) {
Value *Ptr = PTII->getPointerOperand();
if (PTII->getType() == DL.getIntPtrType(Ptr->getType()))
CV = Ptr;
}
}
return CV;
}
/// Given a value comparison instruction,
/// decode all of the 'cases' that it represents and return the 'default' block.
BasicBlock *SimplifyCFGOpt::
GetValueEqualityComparisonCases(TerminatorInst *TI,
std::vector<ValueEqualityComparisonCase>
&Cases) {
if (SwitchInst *SI = dyn_cast<SwitchInst>(TI)) {
Cases.reserve(SI->getNumCases());
for (SwitchInst::CaseIt i = SI->case_begin(), e = SI->case_end(); i != e; ++i)
Cases.push_back(ValueEqualityComparisonCase(i.getCaseValue(),
i.getCaseSuccessor()));
return SI->getDefaultDest();
}
BranchInst *BI = cast<BranchInst>(TI);
ICmpInst *ICI = cast<ICmpInst>(BI->getCondition());
BasicBlock *Succ = BI->getSuccessor(ICI->getPredicate() == ICmpInst::ICMP_NE);
Cases.push_back(ValueEqualityComparisonCase(GetConstantInt(ICI->getOperand(1),
DL),
Succ));
return BI->getSuccessor(ICI->getPredicate() == ICmpInst::ICMP_EQ);
}
/// Given a vector of bb/value pairs, remove any entries
/// in the list that match the specified block.
static void EliminateBlockCases(BasicBlock *BB,
std::vector<ValueEqualityComparisonCase> &Cases) {
Cases.erase(std::remove(Cases.begin(), Cases.end(), BB), Cases.end());
}
/// Return true if there are any keys in C1 that exist in C2 as well.
static bool
ValuesOverlap(std::vector<ValueEqualityComparisonCase> &C1,
std::vector<ValueEqualityComparisonCase > &C2) {
std::vector<ValueEqualityComparisonCase> *V1 = &C1, *V2 = &C2;
// Make V1 be smaller than V2.
if (V1->size() > V2->size())
std::swap(V1, V2);
if (V1->size() == 0) return false;
if (V1->size() == 1) {
// Just scan V2.
ConstantInt *TheVal = (*V1)[0].Value;
for (unsigned i = 0, e = V2->size(); i != e; ++i)
if (TheVal == (*V2)[i].Value)
return true;
}
// Otherwise, just sort both lists and compare element by element.
array_pod_sort(V1->begin(), V1->end());
array_pod_sort(V2->begin(), V2->end());
unsigned i1 = 0, i2 = 0, e1 = V1->size(), e2 = V2->size();
while (i1 != e1 && i2 != e2) {
if ((*V1)[i1].Value == (*V2)[i2].Value)
return true;
if ((*V1)[i1].Value < (*V2)[i2].Value)
++i1;
else
++i2;
}
return false;
}
/// If TI is known to be a terminator instruction and its block is known to
/// only have a single predecessor block, check to see if that predecessor is
/// also a value comparison with the same value, and if that comparison
/// determines the outcome of this comparison. If so, simplify TI. This does a
/// very limited form of jump threading.
bool SimplifyCFGOpt::
SimplifyEqualityComparisonWithOnlyPredecessor(TerminatorInst *TI,
BasicBlock *Pred,
IRBuilder<> &Builder) {
Value *PredVal = isValueEqualityComparison(Pred->getTerminator());
if (!PredVal) return false; // Not a value comparison in predecessor.
Value *ThisVal = isValueEqualityComparison(TI);
assert(ThisVal && "This isn't a value comparison!!");
if (ThisVal != PredVal) return false; // Different predicates.
// TODO: Preserve branch weight metadata, similarly to how
// FoldValueComparisonIntoPredecessors preserves it.
// Find out information about when control will move from Pred to TI's block.
std::vector<ValueEqualityComparisonCase> PredCases;
BasicBlock *PredDef = GetValueEqualityComparisonCases(Pred->getTerminator(),
PredCases);
EliminateBlockCases(PredDef, PredCases); // Remove default from cases.
// Find information about how control leaves this block.
std::vector<ValueEqualityComparisonCase> ThisCases;
BasicBlock *ThisDef = GetValueEqualityComparisonCases(TI, ThisCases);
EliminateBlockCases(ThisDef, ThisCases); // Remove default from cases.
// If TI's block is the default block from Pred's comparison, potentially
// simplify TI based on this knowledge.
if (PredDef == TI->getParent()) {
// If we are here, we know that the value is none of those cases listed in
// PredCases. If there are any cases in ThisCases that are in PredCases, we
// can simplify TI.
if (!ValuesOverlap(PredCases, ThisCases))
return false;
if (isa<BranchInst>(TI)) {
// Okay, one of the successors of this condbr is dead. Convert it to a
// uncond br.
assert(ThisCases.size() == 1 && "Branch can only have one case!");
// Insert the new branch.
Instruction *NI = Builder.CreateBr(ThisDef);
(void) NI;
// Remove PHI node entries for the dead edge.
ThisCases[0].Dest->removePredecessor(TI->getParent());
DEBUG(dbgs() << "Threading pred instr: " << *Pred->getTerminator()
<< "Through successor TI: " << *TI << "Leaving: " << *NI << "\n");
EraseTerminatorInstAndDCECond(TI);
return true;
}
SwitchInst *SI = cast<SwitchInst>(TI);
// Okay, TI has cases that are statically dead, prune them away.
SmallPtrSet<Constant*, 16> DeadCases;
for (unsigned i = 0, e = PredCases.size(); i != e; ++i)
DeadCases.insert(PredCases[i].Value);
DEBUG(dbgs() << "Threading pred instr: " << *Pred->getTerminator()
<< "Through successor TI: " << *TI);
// Collect branch weights into a vector.
SmallVector<uint32_t, 8> Weights;
MDNode *MD = SI->getMetadata(LLVMContext::MD_prof);
bool HasWeight = MD && (MD->getNumOperands() == 2 + SI->getNumCases());
if (HasWeight)
for (unsigned MD_i = 1, MD_e = MD->getNumOperands(); MD_i < MD_e;
++MD_i) {
ConstantInt *CI = mdconst::extract<ConstantInt>(MD->getOperand(MD_i));
Weights.push_back(CI->getValue().getZExtValue());
}
for (SwitchInst::CaseIt i = SI->case_end(), e = SI->case_begin(); i != e;) {
--i;
if (DeadCases.count(i.getCaseValue())) {
if (HasWeight) {
std::swap(Weights[i.getCaseIndex()+1], Weights.back());
Weights.pop_back();
}
i.getCaseSuccessor()->removePredecessor(TI->getParent());
SI->removeCase(i);
}
}
if (HasWeight && Weights.size() >= 2)
SI->setMetadata(LLVMContext::MD_prof,
MDBuilder(SI->getParent()->getContext()).
createBranchWeights(Weights));
DEBUG(dbgs() << "Leaving: " << *TI << "\n");
return true;
}
// Otherwise, TI's block must correspond to some matched value. Find out
// which value (or set of values) this is.
ConstantInt *TIV = nullptr;
BasicBlock *TIBB = TI->getParent();
for (unsigned i = 0, e = PredCases.size(); i != e; ++i)
if (PredCases[i].Dest == TIBB) {
if (TIV)
return false; // Cannot handle multiple values coming to this block.
TIV = PredCases[i].Value;
}
assert(TIV && "No edge from pred to succ?");
// Okay, we found the one constant that our value can be if we get into TI's
// BB. Find out which successor will unconditionally be branched to.
BasicBlock *TheRealDest = nullptr;
for (unsigned i = 0, e = ThisCases.size(); i != e; ++i)
if (ThisCases[i].Value == TIV) {
TheRealDest = ThisCases[i].Dest;
break;
}
// If not handled by any explicit cases, it is handled by the default case.
if (!TheRealDest) TheRealDest = ThisDef;
// Remove PHI node entries for dead edges.
BasicBlock *CheckEdge = TheRealDest;
for (succ_iterator SI = succ_begin(TIBB), e = succ_end(TIBB); SI != e; ++SI)
if (*SI != CheckEdge)
(*SI)->removePredecessor(TIBB);
else
CheckEdge = nullptr;
// Insert the new branch.
Instruction *NI = Builder.CreateBr(TheRealDest);
(void) NI;
DEBUG(dbgs() << "Threading pred instr: " << *Pred->getTerminator()
<< "Through successor TI: " << *TI << "Leaving: " << *NI << "\n");
EraseTerminatorInstAndDCECond(TI);
return true;
}
namespace {
/// This class implements a stable ordering of constant
/// integers that does not depend on their address. This is important for
/// applications that sort ConstantInt's to ensure uniqueness.
struct ConstantIntOrdering {
bool operator()(const ConstantInt *LHS, const ConstantInt *RHS) const {
return LHS->getValue().ult(RHS->getValue());
}
};
}
// HLSL Change: changed calling convention to __cdecl
static int __cdecl ConstantIntSortPredicate(ConstantInt *const *P1,
ConstantInt *const *P2) {
const ConstantInt *LHS = *P1;
const ConstantInt *RHS = *P2;
if (LHS->getValue().ult(RHS->getValue()))
return 1;
if (LHS->getValue() == RHS->getValue())
return 0;
return -1;
}
static inline bool HasBranchWeights(const Instruction* I) {
MDNode *ProfMD = I->getMetadata(LLVMContext::MD_prof);
if (ProfMD && ProfMD->getOperand(0))
if (MDString* MDS = dyn_cast<MDString>(ProfMD->getOperand(0)))
return MDS->getString().equals("branch_weights");
return false;
}
/// Get Weights of a given TerminatorInst, the default weight is at the front
/// of the vector. If TI is a conditional eq, we need to swap the branch-weight
/// metadata.
static void GetBranchWeights(TerminatorInst *TI,
SmallVectorImpl<uint64_t> &Weights) {
MDNode *MD = TI->getMetadata(LLVMContext::MD_prof);
assert(MD);
for (unsigned i = 1, e = MD->getNumOperands(); i < e; ++i) {
ConstantInt *CI = mdconst::extract<ConstantInt>(MD->getOperand(i));
Weights.push_back(CI->getValue().getZExtValue());
}
// If TI is a conditional eq, the default case is the false case,
// and the corresponding branch-weight data is at index 2. We swap the
// default weight to be the first entry.
if (BranchInst* BI = dyn_cast<BranchInst>(TI)) {
assert(Weights.size() == 2);
ICmpInst *ICI = cast<ICmpInst>(BI->getCondition());
if (ICI->getPredicate() == ICmpInst::ICMP_EQ)
std::swap(Weights.front(), Weights.back());
}
}
/// Keep halving the weights until all can fit in uint32_t.
static void FitWeights(MutableArrayRef<uint64_t> Weights) {
uint64_t Max = *std::max_element(Weights.begin(), Weights.end());
if (Max > UINT_MAX) {
unsigned Offset = 32 - countLeadingZeros(Max);
for (uint64_t &I : Weights)
I >>= Offset;
}
}
/// The specified terminator is a value equality comparison instruction
/// (either a switch or a branch on "X == c").
/// See if any of the predecessors of the terminator block are value comparisons
/// on the same value. If so, and if safe to do so, fold them together.
bool SimplifyCFGOpt::FoldValueComparisonIntoPredecessors(TerminatorInst *TI,
IRBuilder<> &Builder) {
#if 0 // HLSL Change - fold to switch will not help hlsl.
BasicBlock *BB = TI->getParent();
Value *CV = isValueEqualityComparison(TI); // CondVal
assert(CV && "Not a comparison?");
bool Changed = false;
SmallVector<BasicBlock*, 16> Preds(pred_begin(BB), pred_end(BB));
while (!Preds.empty()) {
BasicBlock *Pred = Preds.pop_back_val();
// See if the predecessor is a comparison with the same value.
TerminatorInst *PTI = Pred->getTerminator();
Value *PCV = isValueEqualityComparison(PTI); // PredCondVal
if (PCV == CV && SafeToMergeTerminators(TI, PTI)) {
// Figure out which 'cases' to copy from SI to PSI.
std::vector<ValueEqualityComparisonCase> BBCases;
BasicBlock *BBDefault = GetValueEqualityComparisonCases(TI, BBCases);
std::vector<ValueEqualityComparisonCase> PredCases;
BasicBlock *PredDefault = GetValueEqualityComparisonCases(PTI, PredCases);
// Based on whether the default edge from PTI goes to BB or not, fill in
// PredCases and PredDefault with the new switch cases we would like to
// build.
SmallVector<BasicBlock*, 8> NewSuccessors;
// Update the branch weight metadata along the way
SmallVector<uint64_t, 8> Weights;
bool PredHasWeights = HasBranchWeights(PTI);
bool SuccHasWeights = HasBranchWeights(TI);
if (PredHasWeights) {
GetBranchWeights(PTI, Weights);
// branch-weight metadata is inconsistent here.
if (Weights.size() != 1 + PredCases.size())
PredHasWeights = SuccHasWeights = false;
} else if (SuccHasWeights)
// If there are no predecessor weights but there are successor weights,
// populate Weights with 1, which will later be scaled to the sum of
// successor's weights
Weights.assign(1 + PredCases.size(), 1);
SmallVector<uint64_t, 8> SuccWeights;
if (SuccHasWeights) {
GetBranchWeights(TI, SuccWeights);
// branch-weight metadata is inconsistent here.
if (SuccWeights.size() != 1 + BBCases.size())
PredHasWeights = SuccHasWeights = false;
} else if (PredHasWeights)
SuccWeights.assign(1 + BBCases.size(), 1);
if (PredDefault == BB) {
// If this is the default destination from PTI, only the edges in TI
// that don't occur in PTI, or that branch to BB will be activated.
std::set<ConstantInt*, ConstantIntOrdering> PTIHandled;
for (unsigned i = 0, e = PredCases.size(); i != e; ++i)
if (PredCases[i].Dest != BB)
PTIHandled.insert(PredCases[i].Value);
else {
// The default destination is BB, we don't need explicit targets.
std::swap(PredCases[i], PredCases.back());
if (PredHasWeights || SuccHasWeights) {
// Increase weight for the default case.
Weights[0] += Weights[i+1];
std::swap(Weights[i+1], Weights.back());
Weights.pop_back();
}
PredCases.pop_back();
--i; --e;
}
// Reconstruct the new switch statement we will be building.
if (PredDefault != BBDefault) {
PredDefault->removePredecessor(Pred);
PredDefault = BBDefault;
NewSuccessors.push_back(BBDefault);
}
unsigned CasesFromPred = Weights.size();
uint64_t ValidTotalSuccWeight = 0;
for (unsigned i = 0, e = BBCases.size(); i != e; ++i)
if (!PTIHandled.count(BBCases[i].Value) &&
BBCases[i].Dest != BBDefault) {
PredCases.push_back(BBCases[i]);
NewSuccessors.push_back(BBCases[i].Dest);
if (SuccHasWeights || PredHasWeights) {
// The default weight is at index 0, so weight for the ith case
// should be at index i+1. Scale the cases from successor by
// PredDefaultWeight (Weights[0]).
Weights.push_back(Weights[0] * SuccWeights[i+1]);
ValidTotalSuccWeight += SuccWeights[i+1];
}
}
if (SuccHasWeights || PredHasWeights) {
ValidTotalSuccWeight += SuccWeights[0];
// Scale the cases from predecessor by ValidTotalSuccWeight.
for (unsigned i = 1; i < CasesFromPred; ++i)
Weights[i] *= ValidTotalSuccWeight;
// Scale the default weight by SuccDefaultWeight (SuccWeights[0]).
Weights[0] *= SuccWeights[0];
}
} else {
// If this is not the default destination from PSI, only the edges
// in SI that occur in PSI with a destination of BB will be
// activated.
std::set<ConstantInt*, ConstantIntOrdering> PTIHandled;
std::map<ConstantInt*, uint64_t> WeightsForHandled;
for (unsigned i = 0, e = PredCases.size(); i != e; ++i)
if (PredCases[i].Dest == BB) {
PTIHandled.insert(PredCases[i].Value);
if (PredHasWeights || SuccHasWeights) {
WeightsForHandled[PredCases[i].Value] = Weights[i+1];
std::swap(Weights[i+1], Weights.back());
Weights.pop_back();
}
std::swap(PredCases[i], PredCases.back());
PredCases.pop_back();
--i; --e;
}
// Okay, now we know which constants were sent to BB from the
// predecessor. Figure out where they will all go now.
for (unsigned i = 0, e = BBCases.size(); i != e; ++i)
if (PTIHandled.count(BBCases[i].Value)) {
// If this is one we are capable of getting...
if (PredHasWeights || SuccHasWeights)
Weights.push_back(WeightsForHandled[BBCases[i].Value]);
PredCases.push_back(BBCases[i]);
NewSuccessors.push_back(BBCases[i].Dest);
PTIHandled.erase(BBCases[i].Value);// This constant is taken care of
}
// If there are any constants vectored to BB that TI doesn't handle,
// they must go to the default destination of TI.
for (std::set<ConstantInt*, ConstantIntOrdering>::iterator I =
PTIHandled.begin(),
E = PTIHandled.end(); I != E; ++I) {
if (PredHasWeights || SuccHasWeights)
Weights.push_back(WeightsForHandled[*I]);
PredCases.push_back(ValueEqualityComparisonCase(*I, BBDefault));
NewSuccessors.push_back(BBDefault);
}
}
// Okay, at this point, we know which new successor Pred will get. Make
// sure we update the number of entries in the PHI nodes for these
// successors.
for (unsigned i = 0, e = NewSuccessors.size(); i != e; ++i)
AddPredecessorToBlock(NewSuccessors[i], Pred, BB);
Builder.SetInsertPoint(PTI);
// Convert pointer to int before we switch.
if (CV->getType()->isPointerTy()) {
CV = Builder.CreatePtrToInt(CV, DL.getIntPtrType(CV->getType()),
"magicptr");
}
// Now that the successors are updated, create the new Switch instruction.
SwitchInst *NewSI = Builder.CreateSwitch(CV, PredDefault,
PredCases.size());
NewSI->setDebugLoc(PTI->getDebugLoc());
for (unsigned i = 0, e = PredCases.size(); i != e; ++i)
NewSI->addCase(PredCases[i].Value, PredCases[i].Dest);
if (PredHasWeights || SuccHasWeights) {
// Halve the weights if any of them cannot fit in an uint32_t
FitWeights(Weights);
SmallVector<uint32_t, 8> MDWeights(Weights.begin(), Weights.end());
NewSI->setMetadata(LLVMContext::MD_prof,
MDBuilder(BB->getContext()).
createBranchWeights(MDWeights));
}
EraseTerminatorInstAndDCECond(PTI);
// Okay, last check. If BB is still a successor of PSI, then we must
// have an infinite loop case. If so, add an infinitely looping block
// to handle the case to preserve the behavior of the code.
BasicBlock *InfLoopBlock = nullptr;
for (unsigned i = 0, e = NewSI->getNumSuccessors(); i != e; ++i)
if (NewSI->getSuccessor(i) == BB) {
if (!InfLoopBlock) {
// Insert it at the end of the function, because it's either code,
// or it won't matter if it's hot. :)
InfLoopBlock = BasicBlock::Create(BB->getContext(),
"infloop", BB->getParent());
BranchInst::Create(InfLoopBlock, InfLoopBlock);
}
NewSI->setSuccessor(i, InfLoopBlock);
}
Changed = true;
}
}
return Changed;
#else // HLSL Change Begin. // fold to switch will not help hlsl.
return false;
#endif // HLSL Change End.
}
// If we would need to insert a select that uses the value of this invoke
// (comments in HoistThenElseCodeToIf explain why we would need to do this), we
// can't hoist the invoke, as there is nowhere to put the select in this case.
static bool isSafeToHoistInvoke(BasicBlock *BB1, BasicBlock *BB2,
Instruction *I1, Instruction *I2) {
for (succ_iterator SI = succ_begin(BB1), E = succ_end(BB1); SI != E; ++SI) {
PHINode *PN;
for (BasicBlock::iterator BBI = SI->begin();
(PN = dyn_cast<PHINode>(BBI)); ++BBI) {
Value *BB1V = PN->getIncomingValueForBlock(BB1);
Value *BB2V = PN->getIncomingValueForBlock(BB2);
if (BB1V != BB2V && (BB1V==I1 || BB2V==I2)) {
return false;
}
}
}
return true;
}
static bool passingValueIsAlwaysUndefined(Value *V, Instruction *I);
/// Given a conditional branch that goes to BB1 and BB2, hoist any common code
/// in the two blocks up into the branch block. The caller of this function
/// guarantees that BI's block dominates BB1 and BB2.
static bool HoistThenElseCodeToIf(BranchInst *BI,
const TargetTransformInfo &TTI) {
// HLSL Change Begins.
// Leave CSE to target backend.
// Also wave operations should not be CSEed.
return false;
// HLSL Change Ends.
// This does very trivial matching, with limited scanning, to find identical
// instructions in the two blocks. In particular, we don't want to get into
// O(M*N) situations here where M and N are the sizes of BB1 and BB2. As
// such, we currently just scan for obviously identical instructions in an
// identical order.
BasicBlock *BB1 = BI->getSuccessor(0); // The true destination.
BasicBlock *BB2 = BI->getSuccessor(1); // The false destination
BasicBlock::iterator BB1_Itr = BB1->begin();
BasicBlock::iterator BB2_Itr = BB2->begin();
Instruction *I1 = BB1_Itr++, *I2 = BB2_Itr++;
// Skip debug info if it is not identical.
DbgInfoIntrinsic *DBI1 = dyn_cast<DbgInfoIntrinsic>(I1);
DbgInfoIntrinsic *DBI2 = dyn_cast<DbgInfoIntrinsic>(I2);
if (!DBI1 || !DBI2 || !DBI1->isIdenticalToWhenDefined(DBI2)) {
while (isa<DbgInfoIntrinsic>(I1))
I1 = BB1_Itr++;
while (isa<DbgInfoIntrinsic>(I2))
I2 = BB2_Itr++;
}
if (isa<PHINode>(I1) || !I1->isIdenticalToWhenDefined(I2) ||
(isa<InvokeInst>(I1) && !isSafeToHoistInvoke(BB1, BB2, I1, I2)))
return false;
BasicBlock *BIParent = BI->getParent();
bool Changed = false;
do {
// If we are hoisting the terminator instruction, don't move one (making a
// broken BB), instead clone it, and remove BI.
if (isa<TerminatorInst>(I1))
goto HoistTerminator;
if (!TTI.isProfitableToHoist(I1) || !TTI.isProfitableToHoist(I2))
return Changed;
// For a normal instruction, we just move one to right before the branch,
// then replace all uses of the other with the first. Finally, we remove
// the now redundant second instruction.
BIParent->getInstList().splice(BI, BB1->getInstList(), I1);
if (!I2->use_empty())
I2->replaceAllUsesWith(I1);
I1->intersectOptionalDataWith(I2);
unsigned KnownIDs[] = {
LLVMContext::MD_tbaa,
LLVMContext::MD_range,
LLVMContext::MD_fpmath,
LLVMContext::MD_invariant_load,
LLVMContext::MD_nonnull
};
combineMetadata(I1, I2, KnownIDs);
I2->eraseFromParent();
Changed = true;
I1 = BB1_Itr++;
I2 = BB2_Itr++;
// Skip debug info if it is not identical.
DbgInfoIntrinsic *DBI1 = dyn_cast<DbgInfoIntrinsic>(I1);
DbgInfoIntrinsic *DBI2 = dyn_cast<DbgInfoIntrinsic>(I2);
if (!DBI1 || !DBI2 || !DBI1->isIdenticalToWhenDefined(DBI2)) {
while (isa<DbgInfoIntrinsic>(I1))
I1 = BB1_Itr++;
while (isa<DbgInfoIntrinsic>(I2))
I2 = BB2_Itr++;
}
} while (I1->isIdenticalToWhenDefined(I2));
return true;
HoistTerminator:
// It may not be possible to hoist an invoke.
if (isa<InvokeInst>(I1) && !isSafeToHoistInvoke(BB1, BB2, I1, I2))
return Changed;
for (succ_iterator SI = succ_begin(BB1), E = succ_end(BB1); SI != E; ++SI) {
PHINode *PN;
for (BasicBlock::iterator BBI = SI->begin();
(PN = dyn_cast<PHINode>(BBI)); ++BBI) {
Value *BB1V = PN->getIncomingValueForBlock(BB1);
Value *BB2V = PN->getIncomingValueForBlock(BB2);
if (BB1V == BB2V)
continue;
// Check for passingValueIsAlwaysUndefined here because we would rather
// eliminate undefined control flow then converting it to a select.
if (passingValueIsAlwaysUndefined(BB1V, PN) ||
passingValueIsAlwaysUndefined(BB2V, PN))
return Changed;
if (isa<ConstantExpr>(BB1V) && !isSafeToSpeculativelyExecute(BB1V))
return Changed;
if (isa<ConstantExpr>(BB2V) && !isSafeToSpeculativelyExecute(BB2V))
return Changed;
}
}
// Okay, it is safe to hoist the terminator.
Instruction *NT = I1->clone();
BIParent->getInstList().insert(BI, NT);
if (!NT->getType()->isVoidTy()) {
I1->replaceAllUsesWith(NT);
I2->replaceAllUsesWith(NT);
NT->takeName(I1);
}
IRBuilder<true, NoFolder> Builder(NT);
// Hoisting one of the terminators from our successor is a great thing.
// Unfortunately, the successors of the if/else blocks may have PHI nodes in
// them. If they do, all PHI entries for BB1/BB2 must agree for all PHI
// nodes, so we insert select instruction to compute the final result.
std::map<std::pair<Value*,Value*>, SelectInst*> InsertedSelects;
for (succ_iterator SI = succ_begin(BB1), E = succ_end(BB1); SI != E; ++SI) {
PHINode *PN;
for (BasicBlock::iterator BBI = SI->begin();
(PN = dyn_cast<PHINode>(BBI)); ++BBI) {
Value *BB1V = PN->getIncomingValueForBlock(BB1);
Value *BB2V = PN->getIncomingValueForBlock(BB2);
if (BB1V == BB2V) continue;
// These values do not agree. Insert a select instruction before NT
// that determines the right value.
SelectInst *&SI = InsertedSelects[std::make_pair(BB1V, BB2V)];
if (!SI)
SI = cast<SelectInst>
(Builder.CreateSelect(BI->getCondition(), BB1V, BB2V,
BB1V->getName()+"."+BB2V->getName()));
// Make the PHI node use the select for all incoming values for BB1/BB2
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
if (PN->getIncomingBlock(i) == BB1 || PN->getIncomingBlock(i) == BB2)
PN->setIncomingValue(i, SI);
}
}
// Update any PHI nodes in our new successors.
for (succ_iterator SI = succ_begin(BB1), E = succ_end(BB1); SI != E; ++SI)
AddPredecessorToBlock(*SI, BIParent, BB1);
EraseTerminatorInstAndDCECond(BI);
return true;
}
/// Given an unconditional branch that goes to BBEnd,
/// check whether BBEnd has only two predecessors and the other predecessor
/// ends with an unconditional branch. If it is true, sink any common code
/// in the two predecessors to BBEnd.
static bool SinkThenElseCodeToEnd(BranchInst *BI1) {
assert(BI1->isUnconditional());
BasicBlock *BB1 = BI1->getParent();
BasicBlock *BBEnd = BI1->getSuccessor(0);
// Check that BBEnd has two predecessors and the other predecessor ends with
// an unconditional branch.
pred_iterator PI = pred_begin(BBEnd), PE = pred_end(BBEnd);
BasicBlock *Pred0 = *PI++;
if (PI == PE) // Only one predecessor.
return false;
BasicBlock *Pred1 = *PI++;
if (PI != PE) // More than two predecessors.
return false;
BasicBlock *BB2 = (Pred0 == BB1) ? Pred1 : Pred0;
BranchInst *BI2 = dyn_cast<BranchInst>(BB2->getTerminator());
if (!BI2 || !BI2->isUnconditional())
return false;
// Gather the PHI nodes in BBEnd.
SmallDenseMap<std::pair<Value *, Value *>, PHINode *> JointValueMap;
Instruction *FirstNonPhiInBBEnd = nullptr;
for (BasicBlock::iterator I = BBEnd->begin(), E = BBEnd->end(); I != E; ++I) {
if (PHINode *PN = dyn_cast<PHINode>(I)) {
Value *BB1V = PN->getIncomingValueForBlock(BB1);
Value *BB2V = PN->getIncomingValueForBlock(BB2);
JointValueMap[std::make_pair(BB1V, BB2V)] = PN;
} else {
FirstNonPhiInBBEnd = &*I;
break;
}
}
if (!FirstNonPhiInBBEnd)
return false;
// This does very trivial matching, with limited scanning, to find identical
// instructions in the two blocks. We scan backward for obviously identical
// instructions in an identical order.
BasicBlock::InstListType::reverse_iterator RI1 = BB1->getInstList().rbegin(),
RE1 = BB1->getInstList().rend(),
RI2 = BB2->getInstList().rbegin(),
RE2 = BB2->getInstList().rend();
// Skip debug info.
while (RI1 != RE1 && isa<DbgInfoIntrinsic>(&*RI1)) ++RI1;
if (RI1 == RE1)
return false;
while (RI2 != RE2 && isa<DbgInfoIntrinsic>(&*RI2)) ++RI2;
if (RI2 == RE2)
return false;
// Skip the unconditional branches.
++RI1;
++RI2;
bool Changed = false;
while (RI1 != RE1 && RI2 != RE2) {
// Skip debug info.
while (RI1 != RE1 && isa<DbgInfoIntrinsic>(&*RI1)) ++RI1;
if (RI1 == RE1)
return Changed;
while (RI2 != RE2 && isa<DbgInfoIntrinsic>(&*RI2)) ++RI2;
if (RI2 == RE2)
return Changed;
Instruction *I1 = &*RI1, *I2 = &*RI2;
auto InstPair = std::make_pair(I1, I2);
// I1 and I2 should have a single use in the same PHI node, and they
// perform the same operation.
// Cannot move control-flow-involving, volatile loads, vaarg, etc.
if (isa<PHINode>(I1) || isa<PHINode>(I2) ||
isa<TerminatorInst>(I1) || isa<TerminatorInst>(I2) ||
isa<LandingPadInst>(I1) || isa<LandingPadInst>(I2) ||
isa<AllocaInst>(I1) || isa<AllocaInst>(I2) ||
I1->mayHaveSideEffects() || I2->mayHaveSideEffects() ||
I1->mayReadOrWriteMemory() || I2->mayReadOrWriteMemory() ||
!I1->hasOneUse() || !I2->hasOneUse() ||
!JointValueMap.count(InstPair))
return Changed;
// Check whether we should swap the operands of ICmpInst.
// TODO: Add support of communativity.
ICmpInst *ICmp1 = dyn_cast<ICmpInst>(I1), *ICmp2 = dyn_cast<ICmpInst>(I2);
bool SwapOpnds = false;
if (ICmp1 && ICmp2 &&
ICmp1->getOperand(0) != ICmp2->getOperand(0) &&
ICmp1->getOperand(1) != ICmp2->getOperand(1) &&
(ICmp1->getOperand(0) == ICmp2->getOperand(1) ||
ICmp1->getOperand(1) == ICmp2->getOperand(0))) {
ICmp2->swapOperands();
SwapOpnds = true;
}
if (!I1->isSameOperationAs(I2)) {
if (SwapOpnds)
ICmp2->swapOperands();
return Changed;
}
// The operands should be either the same or they need to be generated
// with a PHI node after sinking. We only handle the case where there is
// a single pair of different operands.
Value *DifferentOp1 = nullptr, *DifferentOp2 = nullptr;
unsigned Op1Idx = ~0U;
for (unsigned I = 0, E = I1->getNumOperands(); I != E; ++I) {
if (I1->getOperand(I) == I2->getOperand(I))
continue;
// Early exit if we have more-than one pair of different operands or if
// we need a PHI node to replace a constant.
if (Op1Idx != ~0U ||
isa<Constant>(I1->getOperand(I)) ||
isa<Constant>(I2->getOperand(I))) {
// If we can't sink the instructions, undo the swapping.
if (SwapOpnds)
ICmp2->swapOperands();
return Changed;
}
DifferentOp1 = I1->getOperand(I);
Op1Idx = I;
DifferentOp2 = I2->getOperand(I);
}
// HLSL Change Begin.
// Don't sink struct type which will generate struct PhiNode to make sure
// struct type value only used by Extract/InsertValue.
if (DifferentOp1 && DifferentOp1->getType()->isStructTy())
return Changed;
// HLSL Change End.
DEBUG(dbgs() << "SINK common instructions " << *I1 << "\n");
DEBUG(dbgs() << " " << *I2 << "\n");
// We insert the pair of different operands to JointValueMap and
// remove (I1, I2) from JointValueMap.
if (Op1Idx != ~0U) {
auto &NewPN = JointValueMap[std::make_pair(DifferentOp1, DifferentOp2)];
if (!NewPN) {
NewPN =
PHINode::Create(DifferentOp1->getType(), 2,
DifferentOp1->getName() + ".sink", BBEnd->begin());
NewPN->addIncoming(DifferentOp1, BB1);
NewPN->addIncoming(DifferentOp2, BB2);
DEBUG(dbgs() << "Create PHI node " << *NewPN << "\n";);
}
// I1 should use NewPN instead of DifferentOp1.
I1->setOperand(Op1Idx, NewPN);
}
PHINode *OldPN = JointValueMap[InstPair];
JointValueMap.erase(InstPair);
// We need to update RE1 and RE2 if we are going to sink the first
// instruction in the basic block down.
bool UpdateRE1 = (I1 == BB1->begin()), UpdateRE2 = (I2 == BB2->begin());
// Sink the instruction.
BBEnd->getInstList().splice(FirstNonPhiInBBEnd, BB1->getInstList(), I1);
if (!OldPN->use_empty())
OldPN->replaceAllUsesWith(I1);
OldPN->eraseFromParent();
if (!I2->use_empty())
I2->replaceAllUsesWith(I1);
I1->intersectOptionalDataWith(I2);
// TODO: Use combineMetadata here to preserve what metadata we can
// (analogous to the hoisting case above).
I2->eraseFromParent();
if (UpdateRE1)
RE1 = BB1->getInstList().rend();
if (UpdateRE2)
RE2 = BB2->getInstList().rend();
FirstNonPhiInBBEnd = I1;
NumSinkCommons++;
Changed = true;
}
return Changed;
}
/// \brief Determine if we can hoist sink a sole store instruction out of a
/// conditional block.
///
/// We are looking for code like the following:
/// BrBB:
/// store i32 %add, i32* %arrayidx2
/// ... // No other stores or function calls (we could be calling a memory
/// ... // function).
/// %cmp = icmp ult %x, %y
/// br i1 %cmp, label %EndBB, label %ThenBB
/// ThenBB:
/// store i32 %add5, i32* %arrayidx2
/// br label EndBB
/// EndBB:
/// ...
/// We are going to transform this into:
/// BrBB:
/// store i32 %add, i32* %arrayidx2
/// ... //
/// %cmp = icmp ult %x, %y
/// %add.add5 = select i1 %cmp, i32 %add, %add5
/// store i32 %add.add5, i32* %arrayidx2
/// ...
///
/// \return The pointer to the value of the previous store if the store can be
/// hoisted into the predecessor block. 0 otherwise.
static Value *isSafeToSpeculateStore(Instruction *I, BasicBlock *BrBB,
BasicBlock *StoreBB, BasicBlock *EndBB) {
StoreInst *StoreToHoist = dyn_cast<StoreInst>(I);
if (!StoreToHoist)
return nullptr;
// Volatile or atomic.
if (!StoreToHoist->isSimple())
return nullptr;
Value *StorePtr = StoreToHoist->getPointerOperand();
// Look for a store to the same pointer in BrBB.
unsigned MaxNumInstToLookAt = 10;
for (BasicBlock::reverse_iterator RI = BrBB->rbegin(),
RE = BrBB->rend(); RI != RE && (--MaxNumInstToLookAt); ++RI) {
Instruction *CurI = &*RI;
// Could be calling an instruction that effects memory like free().
if (CurI->mayHaveSideEffects() && !isa<StoreInst>(CurI))
return nullptr;
StoreInst *SI = dyn_cast<StoreInst>(CurI);
// Found the previous store make sure it stores to the same location.
if (SI && SI->getPointerOperand() == StorePtr)
// Found the previous store, return its value operand.
return SI->getValueOperand();
else if (SI)
return nullptr; // Unknown store.
}
return nullptr;
}
/// \brief Speculate a conditional basic block flattening the CFG.
///
/// Note that this is a very risky transform currently. Speculating
/// instructions like this is most often not desirable. Instead, there is an MI
/// pass which can do it with full awareness of the resource constraints.
/// However, some cases are "obvious" and we should do directly. An example of
/// this is speculating a single, reasonably cheap instruction.
///
/// There is only one distinct advantage to flattening the CFG at the IR level:
/// it makes very common but simplistic optimizations such as are common in
/// instcombine and the DAG combiner more powerful by removing CFG edges and
/// modeling their effects with easier to reason about SSA value graphs.
///
///
/// An illustration of this transform is turning this IR:
/// \code
/// BB:
/// %cmp = icmp ult %x, %y
/// br i1 %cmp, label %EndBB, label %ThenBB
/// ThenBB:
/// %sub = sub %x, %y
/// br label BB2
/// EndBB:
/// %phi = phi [ %sub, %ThenBB ], [ 0, %EndBB ]
/// ...
/// \endcode
///
/// Into this IR:
/// \code
/// BB:
/// %cmp = icmp ult %x, %y
/// %sub = sub %x, %y
/// %cond = select i1 %cmp, 0, %sub
/// ...
/// \endcode
///
/// \returns true if the conditional block is removed.
static bool SpeculativelyExecuteBB(BranchInst *BI, BasicBlock *ThenBB,
const TargetTransformInfo &TTI) {
// HLSL Change Begins.
// Skip block with control flow hint.
if (hlsl::DxilMDHelper::HasControlFlowHintToPreventFlatten(BI)) {
return false;
}
// HLSL Change Ends.
// Be conservative for now. FP select instruction can often be expensive.
Value *BrCond = BI->getCondition();
if (isa<FCmpInst>(BrCond))
return false;
BasicBlock *BB = BI->getParent();
BasicBlock *EndBB = ThenBB->getTerminator()->getSuccessor(0);
// If ThenBB is actually on the false edge of the conditional branch, remember
// to swap the select operands later.
bool Invert = false;
if (ThenBB != BI->getSuccessor(0)) {
assert(ThenBB == BI->getSuccessor(1) && "No edge from 'if' block?");
Invert = true;
}
assert(EndBB == BI->getSuccessor(!Invert) && "No edge from to end block");
// Keep a count of how many times instructions are used within CondBB when
// they are candidates for sinking into CondBB. Specifically:
// - They are defined in BB, and
// - They have no side effects, and
// - All of their uses are in CondBB.
SmallDenseMap<Instruction *, unsigned, 4> SinkCandidateUseCounts;
unsigned SpeculationCost = 0;
Value *SpeculatedStoreValue = nullptr;
StoreInst *SpeculatedStore = nullptr;
for (BasicBlock::iterator BBI = ThenBB->begin(),
BBE = std::prev(ThenBB->end());
BBI != BBE; ++BBI) {
Instruction *I = BBI;
// Skip debug info.
if (isa<DbgInfoIntrinsic>(I))
continue;
// Only speculatively execute a single instruction (not counting the
// terminator) for now.
++SpeculationCost;
if (SpeculationCost > 1)
return false;
// Don't hoist the instruction if it's unsafe or expensive.
if (!isSafeToSpeculativelyExecute(I) &&
!(HoistCondStores && (SpeculatedStoreValue = isSafeToSpeculateStore(
I, BB, ThenBB, EndBB))))
return false;
if (!SpeculatedStoreValue &&
ComputeSpeculationCost(I, TTI) >
PHINodeFoldingThreshold * TargetTransformInfo::TCC_Basic)
return false;
// Store the store speculation candidate.
if (SpeculatedStoreValue)
SpeculatedStore = cast<StoreInst>(I);
// Do not hoist the instruction if any of its operands are defined but not
// used in BB. The transformation will prevent the operand from
// being sunk into the use block.
for (User::op_iterator i = I->op_begin(), e = I->op_end();
i != e; ++i) {
Instruction *OpI = dyn_cast<Instruction>(*i);
if (!OpI || OpI->getParent() != BB ||
OpI->mayHaveSideEffects())
continue; // Not a candidate for sinking.
++SinkCandidateUseCounts[OpI];
}
}
// Consider any sink candidates which are only used in CondBB as costs for
// speculation. Note, while we iterate over a DenseMap here, we are summing
// and so iteration order isn't significant.
for (SmallDenseMap<Instruction *, unsigned, 4>::iterator I =
SinkCandidateUseCounts.begin(), E = SinkCandidateUseCounts.end();
I != E; ++I)
if (I->first->getNumUses() == I->second) {
++SpeculationCost;
if (SpeculationCost > 1)
return false;
}
// Check that the PHI nodes can be converted to selects.
bool HaveRewritablePHIs = false;
for (BasicBlock::iterator I = EndBB->begin();
PHINode *PN = dyn_cast<PHINode>(I); ++I) {
Value *OrigV = PN->getIncomingValueForBlock(BB);
Value *ThenV = PN->getIncomingValueForBlock(ThenBB);
// FIXME: Try to remove some of the duplication with HoistThenElseCodeToIf.
// Skip PHIs which are trivial.
if (ThenV == OrigV)
continue;
// Don't convert to selects if we could remove undefined behavior instead.
if (passingValueIsAlwaysUndefined(OrigV, PN) ||
passingValueIsAlwaysUndefined(ThenV, PN))
return false;
HaveRewritablePHIs = true;
ConstantExpr *OrigCE = dyn_cast<ConstantExpr>(OrigV);
ConstantExpr *ThenCE = dyn_cast<ConstantExpr>(ThenV);
if (!OrigCE && !ThenCE)
continue; // Known safe and cheap.
if ((ThenCE && !isSafeToSpeculativelyExecute(ThenCE)) ||
(OrigCE && !isSafeToSpeculativelyExecute(OrigCE)))
return false;
unsigned OrigCost = OrigCE ? ComputeSpeculationCost(OrigCE, TTI) : 0;
unsigned ThenCost = ThenCE ? ComputeSpeculationCost(ThenCE, TTI) : 0;
unsigned MaxCost = 2 * PHINodeFoldingThreshold *
TargetTransformInfo::TCC_Basic;
if (OrigCost + ThenCost > MaxCost)
return false;
// Account for the cost of an unfolded ConstantExpr which could end up
// getting expanded into Instructions.
// FIXME: This doesn't account for how many operations are combined in the
// constant expression.
++SpeculationCost;
if (SpeculationCost > 1)
return false;
}
// If there are no PHIs to process, bail early. This helps ensure idempotence
// as well.
if (!HaveRewritablePHIs && !(HoistCondStores && SpeculatedStoreValue))
return false;
// If we get here, we can hoist the instruction and if-convert.
DEBUG(dbgs() << "SPECULATIVELY EXECUTING BB" << *ThenBB << "\n";);
// Insert a select of the value of the speculated store.
if (SpeculatedStoreValue) {
IRBuilder<true, NoFolder> Builder(BI);
Value *TrueV = SpeculatedStore->getValueOperand();
Value *FalseV = SpeculatedStoreValue;
if (Invert)
std::swap(TrueV, FalseV);
Value *S = Builder.CreateSelect(BrCond, TrueV, FalseV, TrueV->getName() +
"." + FalseV->getName());
SpeculatedStore->setOperand(0, S);
}
// Hoist the instructions.
BB->getInstList().splice(BI, ThenBB->getInstList(), ThenBB->begin(),
std::prev(ThenBB->end()));
// Insert selects and rewrite the PHI operands.
IRBuilder<true, NoFolder> Builder(BI);
for (BasicBlock::iterator I = EndBB->begin();
PHINode *PN = dyn_cast<PHINode>(I); ++I) {
unsigned OrigI = PN->getBasicBlockIndex(BB);
unsigned ThenI = PN->getBasicBlockIndex(ThenBB);
Value *OrigV = PN->getIncomingValue(OrigI);
Value *ThenV = PN->getIncomingValue(ThenI);
// Skip PHIs which are trivial.
if (OrigV == ThenV)
continue;
// Create a select whose true value is the speculatively executed value and
// false value is the preexisting value. Swap them if the branch
// destinations were inverted.
Value *TrueV = ThenV, *FalseV = OrigV;
if (Invert)
std::swap(TrueV, FalseV);
Value *V = Builder.CreateSelect(BrCond, TrueV, FalseV,
TrueV->getName() + "." + FalseV->getName());
PN->setIncomingValue(OrigI, V);
PN->setIncomingValue(ThenI, V);
}
++NumSpeculations;
return true;
}
#if 0 // HLSL Change - Unused function
/// \returns True if this block contains a CallInst with the NoDuplicate
/// attribute.
static bool HasNoDuplicateCall(const BasicBlock *BB) {
for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E; ++I) {
const CallInst *CI = dyn_cast<CallInst>(I);
if (!CI)
continue;
if (CI->cannotDuplicate())
return true;
}
return false;
}
#endif
/// Return true if we can thread a branch across this block.
static bool BlockIsSimpleEnoughToThreadThrough(BasicBlock *BB) {
BranchInst *BI = cast<BranchInst>(BB->getTerminator());
unsigned Size = 0;
for (BasicBlock::iterator BBI = BB->begin(); &*BBI != BI; ++BBI) {
if (isa<DbgInfoIntrinsic>(BBI))
continue;
if (Size > 10) return false; // Don't clone large BB's.
++Size;
// We can only support instructions that do not define values that are
// live outside of the current basic block.
for (User *U : BBI->users()) {
Instruction *UI = cast<Instruction>(U);
if (UI->getParent() != BB || isa<PHINode>(UI)) return false;
}
// Looks ok, continue checking.
}
return true;
}
#if 0 // HLSL Change - Unused function
/// If we have a conditional branch on a PHI node value that is defined in the
/// same block as the branch and if any PHI entries are constants, thread edges
/// corresponding to that entry to be branches to their ultimate destination.
static bool FoldCondBranchOnPHI(BranchInst *BI, const DataLayout &DL) {
BasicBlock *BB = BI->getParent();
PHINode *PN = dyn_cast<PHINode>(BI->getCondition());
// NOTE: we currently cannot transform this case if the PHI node is used
// outside of the block.
if (!PN || PN->getParent() != BB || !PN->hasOneUse())
return false;
// Degenerate case of a single entry PHI.
if (PN->getNumIncomingValues() == 1) {
FoldSingleEntryPHINodes(PN->getParent());
return true;
}
// Now we know that this block has multiple preds and two succs.
if (!BlockIsSimpleEnoughToThreadThrough(BB)) return false;
if (HasNoDuplicateCall(BB)) return false;
// Okay, this is a simple enough basic block. See if any phi values are
// constants.
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
ConstantInt *CB = dyn_cast<ConstantInt>(PN->getIncomingValue(i));
if (!CB || !CB->getType()->isIntegerTy(1)) continue;
// Okay, we now know that all edges from PredBB should be revectored to
// branch to RealDest.
BasicBlock *PredBB = PN->getIncomingBlock(i);
BasicBlock *RealDest = BI->getSuccessor(!CB->getZExtValue());
if (RealDest == BB) continue; // Skip self loops.
// Skip if the predecessor's terminator is an indirect branch.
if (isa<IndirectBrInst>(PredBB->getTerminator())) continue;
// The dest block might have PHI nodes, other predecessors and other
// difficult cases. Instead of being smart about this, just insert a new
// block that jumps to the destination block, effectively splitting
// the edge we are about to create.
BasicBlock *EdgeBB = BasicBlock::Create(BB->getContext(),
RealDest->getName()+".critedge",
RealDest->getParent(), RealDest);
BranchInst::Create(RealDest, EdgeBB);
// Update PHI nodes.
AddPredecessorToBlock(RealDest, EdgeBB, BB);
// BB may have instructions that are being threaded over. Clone these
// instructions into EdgeBB. We know that there will be no uses of the
// cloned instructions outside of EdgeBB.
BasicBlock::iterator InsertPt = EdgeBB->begin();
DenseMap<Value*, Value*> TranslateMap; // Track translated values.
for (BasicBlock::iterator BBI = BB->begin(); &*BBI != BI; ++BBI) {
if (PHINode *PN = dyn_cast<PHINode>(BBI)) {
TranslateMap[PN] = PN->getIncomingValueForBlock(PredBB);
continue;
}
// Clone the instruction.
Instruction *N = BBI->clone();
if (BBI->hasName()) N->setName(BBI->getName()+".c");
// Update operands due to translation.
for (User::op_iterator i = N->op_begin(), e = N->op_end();
i != e; ++i) {
DenseMap<Value*, Value*>::iterator PI = TranslateMap.find(*i);
if (PI != TranslateMap.end())
*i = PI->second;
}
// Check for trivial simplification.
if (Value *V = SimplifyInstruction(N, DL)) {
TranslateMap[BBI] = V;
delete N; // Instruction folded away, don't need actual inst
} else {
// Insert the new instruction into its new home.
EdgeBB->getInstList().insert(InsertPt, N);
if (!BBI->use_empty())
TranslateMap[BBI] = N;
}
}
// Loop over all of the edges from PredBB to BB, changing them to branch
// to EdgeBB instead.
TerminatorInst *PredBBTI = PredBB->getTerminator();
for (unsigned i = 0, e = PredBBTI->getNumSuccessors(); i != e; ++i)
if (PredBBTI->getSuccessor(i) == BB) {
BB->removePredecessor(PredBB);
PredBBTI->setSuccessor(i, EdgeBB);
}
// Recurse, simplifying any other constants.
return FoldCondBranchOnPHI(BI, DL) | true;
}
return false;
}
#endif
/// Given a BB that starts with the specified two-entry PHI node,
/// see if we can eliminate it.
static bool FoldTwoEntryPHINode(PHINode *PN, const TargetTransformInfo &TTI,
const DataLayout &DL) {
// Ok, this is a two entry PHI node. Check to see if this is a simple "if
// statement", which has a very simple dominance structure. Basically, we
// are trying to find the condition that is being branched on, which
// subsequently causes this merge to happen. We really want control
// dependence information for this check, but simplifycfg can't keep it up
// to date, and this catches most of the cases we care about anyway.
BasicBlock *BB = PN->getParent();
BasicBlock *IfTrue, *IfFalse;
Value *IfCond = GetIfCondition(BB, IfTrue, IfFalse);
if (!IfCond ||
// Don't bother if the branch will be constant folded trivially.
isa<ConstantInt>(IfCond))
return false;
// HLSL Change Begins: Patching in llvm/llvm-project@602ab24
// Don't try to fold an unreachable block. For example, the phi node itself
// can't be the candidate if-condition for a select that we want to form.
if (auto *IfCondPhiInst = dyn_cast<PHINode>(IfCond))
if (IfCondPhiInst->getParent() == BB)
return false;
// HLSL Change Ends.
// Okay, we found that we can merge this two-entry phi node into a select.
// Doing so would require us to fold *all* two entry phi nodes in this block.
// At some point this becomes non-profitable (particularly if the target
// doesn't support cmov's). Only do this transformation if there are two or
// fewer PHI nodes in this block.
unsigned NumPhis = 0;
for (BasicBlock::iterator I = BB->begin(); isa<PHINode>(I); ++NumPhis, ++I)
if (NumPhis > 2)
return false;
// Loop over the PHI's seeing if we can promote them all to select
// instructions. While we are at it, keep track of the instructions
// that need to be moved to the dominating block.
SmallPtrSet<Instruction*, 4> AggressiveInsts;
unsigned MaxCostVal0 = PHINodeFoldingThreshold,
MaxCostVal1 = PHINodeFoldingThreshold;
MaxCostVal0 *= TargetTransformInfo::TCC_Basic;
MaxCostVal1 *= TargetTransformInfo::TCC_Basic;
for (BasicBlock::iterator II = BB->begin(); isa<PHINode>(II);) {
PHINode *PN = cast<PHINode>(II++);
if (Value *V = SimplifyInstruction(PN, DL)) {
PN->replaceAllUsesWith(V);
PN->eraseFromParent();
continue;
}
if (!DominatesMergePoint(PN->getIncomingValue(0), BB, &AggressiveInsts,
MaxCostVal0, TTI) ||
!DominatesMergePoint(PN->getIncomingValue(1), BB, &AggressiveInsts,
MaxCostVal1, TTI))
return false;
}
// If we folded the first phi, PN dangles at this point. Refresh it. If
// we ran out of PHIs then we simplified them all.
PN = dyn_cast<PHINode>(BB->begin());
if (!PN) return true;
// Don't fold i1 branches on PHIs which contain binary operators. These can
// often be turned into switches and other things.
if (PN->getType()->isIntegerTy(1) &&
(isa<BinaryOperator>(PN->getIncomingValue(0)) ||
isa<BinaryOperator>(PN->getIncomingValue(1)) ||
isa<BinaryOperator>(IfCond)))
return false;
// If we all PHI nodes are promotable, check to make sure that all
// instructions in the predecessor blocks can be promoted as well. If
// not, we won't be able to get rid of the control flow, so it's not
// worth promoting to select instructions.
BasicBlock *DomBlock = nullptr;
BasicBlock *IfBlock1 = PN->getIncomingBlock(0);
BasicBlock *IfBlock2 = PN->getIncomingBlock(1);
if (cast<BranchInst>(IfBlock1->getTerminator())->isConditional()) {
IfBlock1 = nullptr;
} else {
DomBlock = *pred_begin(IfBlock1);
for (BasicBlock::iterator I = IfBlock1->begin();!isa<TerminatorInst>(I);++I)
if (!AggressiveInsts.count(I) && !isa<DbgInfoIntrinsic>(I)) {
// This is not an aggressive instruction that we can promote.
// Because of this, we won't be able to get rid of the control
// flow, so the xform is not worth it.
return false;
}
}
if (cast<BranchInst>(IfBlock2->getTerminator())->isConditional()) {
IfBlock2 = nullptr;
} else {
DomBlock = *pred_begin(IfBlock2);
for (BasicBlock::iterator I = IfBlock2->begin();!isa<TerminatorInst>(I);++I)
if (!AggressiveInsts.count(I) && !isa<DbgInfoIntrinsic>(I)) {
// This is not an aggressive instruction that we can promote.
// Because of this, we won't be able to get rid of the control
// flow, so the xform is not worth it.
return false;
}
}
DEBUG(dbgs() << "FOUND IF CONDITION! " << *IfCond << " T: "
<< IfTrue->getName() << " F: " << IfFalse->getName() << "\n");
// If we can still promote the PHI nodes after this gauntlet of tests,
// do all of the PHI's now.
Instruction *InsertPt = DomBlock->getTerminator();
// HLSL Change Begins.
// Skip block with control flow hint.
if (hlsl::DxilMDHelper::HasControlFlowHintToPreventFlatten(InsertPt)) {
return false;
}
// HLSL Change Ends.
IRBuilder<true, NoFolder> Builder(InsertPt);
// Move all 'aggressive' instructions, which are defined in the
// conditional parts of the if's up to the dominating block.
if (IfBlock1)
DomBlock->getInstList().splice(InsertPt,
IfBlock1->getInstList(), IfBlock1->begin(),
IfBlock1->getTerminator());
if (IfBlock2)
DomBlock->getInstList().splice(InsertPt,
IfBlock2->getInstList(), IfBlock2->begin(),
IfBlock2->getTerminator());
while (PHINode *PN = dyn_cast<PHINode>(BB->begin())) {
// Change the PHI node into a select instruction.
Value *TrueVal = PN->getIncomingValue(PN->getIncomingBlock(0) == IfFalse);
Value *FalseVal = PN->getIncomingValue(PN->getIncomingBlock(0) == IfTrue);
SelectInst *NV =
cast<SelectInst>(Builder.CreateSelect(IfCond, TrueVal, FalseVal, ""));
PN->replaceAllUsesWith(NV);
NV->takeName(PN);
PN->eraseFromParent();
}
// At this point, IfBlock1 and IfBlock2 are both empty, so our if statement
// has been flattened. Change DomBlock to jump directly to our new block to
// avoid other simplifycfg's kicking in on the diamond.
TerminatorInst *OldTI = DomBlock->getTerminator();
Builder.SetInsertPoint(OldTI);
Builder.CreateBr(BB);
OldTI->eraseFromParent();
return true;
}
/// If we found a conditional branch that goes to two returning blocks,
/// try to merge them together into one return,
/// introducing a select if the return values disagree.
static bool SimplifyCondBranchToTwoReturns(BranchInst *BI,
IRBuilder<> &Builder) {
assert(BI->isConditional() && "Must be a conditional branch");
BasicBlock *TrueSucc = BI->getSuccessor(0);
BasicBlock *FalseSucc = BI->getSuccessor(1);
ReturnInst *TrueRet = cast<ReturnInst>(TrueSucc->getTerminator());
ReturnInst *FalseRet = cast<ReturnInst>(FalseSucc->getTerminator());
// Check to ensure both blocks are empty (just a return) or optionally empty
// with PHI nodes. If there are other instructions, merging would cause extra
// computation on one path or the other.
if (!TrueSucc->getFirstNonPHIOrDbg()->isTerminator())
return false;
if (!FalseSucc->getFirstNonPHIOrDbg()->isTerminator())
return false;
Builder.SetInsertPoint(BI);
// Okay, we found a branch that is going to two return nodes. If
// there is no return value for this function, just change the
// branch into a return.
if (FalseRet->getNumOperands() == 0) {
TrueSucc->removePredecessor(BI->getParent());
FalseSucc->removePredecessor(BI->getParent());
Builder.CreateRetVoid();
EraseTerminatorInstAndDCECond(BI);
return true;
}
// Otherwise, figure out what the true and false return values are
// so we can insert a new select instruction.
Value *TrueValue = TrueRet->getReturnValue();
Value *FalseValue = FalseRet->getReturnValue();
// Unwrap any PHI nodes in the return blocks.
if (PHINode *TVPN = dyn_cast_or_null<PHINode>(TrueValue))
if (TVPN->getParent() == TrueSucc)
TrueValue = TVPN->getIncomingValueForBlock(BI->getParent());
if (PHINode *FVPN = dyn_cast_or_null<PHINode>(FalseValue))
if (FVPN->getParent() == FalseSucc)
FalseValue = FVPN->getIncomingValueForBlock(BI->getParent());
// In order for this transformation to be safe, we must be able to
// unconditionally execute both operands to the return. This is
// normally the case, but we could have a potentially-trapping
// constant expression that prevents this transformation from being
// safe.
if (ConstantExpr *TCV = dyn_cast_or_null<ConstantExpr>(TrueValue))
if (TCV->canTrap())
return false;
if (ConstantExpr *FCV = dyn_cast_or_null<ConstantExpr>(FalseValue))
if (FCV->canTrap())
return false;
// Okay, we collected all the mapped values and checked them for sanity, and
// defined to really do this transformation. First, update the CFG.
TrueSucc->removePredecessor(BI->getParent());
FalseSucc->removePredecessor(BI->getParent());
// Insert select instructions where needed.
Value *BrCond = BI->getCondition();
if (TrueValue) {
// Insert a select if the results differ.
if (TrueValue == FalseValue || isa<UndefValue>(FalseValue)) {
} else if (isa<UndefValue>(TrueValue)) {
TrueValue = FalseValue;
} else {
TrueValue = Builder.CreateSelect(BrCond, TrueValue,
FalseValue, "retval");
}
}
Value *RI = !TrueValue ?
Builder.CreateRetVoid() : Builder.CreateRet(TrueValue);
(void) RI;
DEBUG(dbgs() << "\nCHANGING BRANCH TO TWO RETURNS INTO SELECT:"
<< "\n " << *BI << "NewRet = " << *RI
<< "TRUEBLOCK: " << *TrueSucc << "FALSEBLOCK: "<< *FalseSucc);
EraseTerminatorInstAndDCECond(BI);
return true;
}
/// Given a conditional BranchInstruction, retrieve the probabilities of the
/// branch taking each edge. Fills in the two APInt parameters and returns true,
/// or returns false if no or invalid metadata was found.
static bool ExtractBranchMetadata(BranchInst *BI,
uint64_t &ProbTrue, uint64_t &ProbFalse) {
assert(BI->isConditional() &&
"Looking for probabilities on unconditional branch?");
MDNode *ProfileData = BI->getMetadata(LLVMContext::MD_prof);
if (!ProfileData || ProfileData->getNumOperands() != 3) return false;
ConstantInt *CITrue =
mdconst::dyn_extract<ConstantInt>(ProfileData->getOperand(1));
ConstantInt *CIFalse =
mdconst::dyn_extract<ConstantInt>(ProfileData->getOperand(2));
if (!CITrue || !CIFalse) return false;
ProbTrue = CITrue->getValue().getZExtValue();
ProbFalse = CIFalse->getValue().getZExtValue();
return true;
}
/// Return true if the given instruction is available
/// in its predecessor block. If yes, the instruction will be removed.
static bool checkCSEInPredecessor(Instruction *Inst, BasicBlock *PB) {
if (!isa<BinaryOperator>(Inst) && !isa<CmpInst>(Inst))
return false;
for (BasicBlock::iterator I = PB->begin(), E = PB->end(); I != E; I++) {
Instruction *PBI = &*I;
// Check whether Inst and PBI generate the same value.
if (Inst->isIdenticalTo(PBI)) {
Inst->replaceAllUsesWith(PBI);
Inst->eraseFromParent();
return true;
}
}
return false;
}
/// If this basic block is simple enough, and if a predecessor branches to us
/// and one of our successors, fold the block into the predecessor and use
/// logical operations to pick the right destination.
bool llvm::FoldBranchToCommonDest(BranchInst *BI, unsigned BonusInstThreshold) {
BasicBlock *BB = BI->getParent();
Instruction *Cond = nullptr;
if (BI->isConditional())
Cond = dyn_cast<Instruction>(BI->getCondition());
else {
// For unconditional branch, check for a simple CFG pattern, where
// BB has a single predecessor and BB's successor is also its predecessor's
// successor. If such pattern exisits, check for CSE between BB and its
// predecessor.
if (BasicBlock *PB = BB->getSinglePredecessor())
if (BranchInst *PBI = dyn_cast<BranchInst>(PB->getTerminator()))
if (PBI->isConditional() &&
(BI->getSuccessor(0) == PBI->getSuccessor(0) ||
BI->getSuccessor(0) == PBI->getSuccessor(1))) {
for (BasicBlock::iterator I = BB->begin(), E = BB->end();
I != E; ) {
Instruction *Curr = I++;
if (isa<DbgInfoIntrinsic>(Curr)) continue; // HLSL Change - Ignore debug insts
if (isa<CmpInst>(Curr)) {
Cond = Curr;
break;
}
// Quit if we can't remove this instruction.
if (!checkCSEInPredecessor(Curr, PB))
return false;
}
}
if (!Cond)
return false;
}
if (!Cond || (!isa<CmpInst>(Cond) && !isa<BinaryOperator>(Cond)) ||
Cond->getParent() != BB || !Cond->hasOneUse())
return false;
// Make sure the instruction after the condition is the cond branch.
BasicBlock::iterator CondIt = Cond; ++CondIt;
// Ignore dbg intrinsics.
while (isa<DbgInfoIntrinsic>(CondIt)) ++CondIt;
if (&*CondIt != BI)
return false;
// Only allow this transformation if computing the condition doesn't involve
// too many instructions and these involved instructions can be executed
// unconditionally. We denote all involved instructions except the condition
// as "bonus instructions", and only allow this transformation when the
// number of the bonus instructions does not exceed a certain threshold.
unsigned NumBonusInsts = 0;
for (auto I = BB->begin(); Cond != I; ++I) {
// Ignore dbg intrinsics.
if (isa<DbgInfoIntrinsic>(I))
continue;
if (!I->hasOneUse() || !isSafeToSpeculativelyExecute(I))
return false;
// I has only one use and can be executed unconditionally.
Instruction *User = dyn_cast<Instruction>(I->user_back());
if (User == nullptr || User->getParent() != BB)
return false;
// I is used in the same BB. Since BI uses Cond and doesn't have more slots
// to use any other instruction, User must be an instruction between next(I)
// and Cond.
++NumBonusInsts;
// Early exits once we reach the limit.
if (NumBonusInsts > BonusInstThreshold)
return false;
}
// Cond is known to be a compare or binary operator. Check to make sure that
// neither operand is a potentially-trapping constant expression.
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Cond->getOperand(0)))
if (CE->canTrap())
return false;
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Cond->getOperand(1)))
if (CE->canTrap())
return false;
// Finally, don't infinitely unroll conditional loops.
BasicBlock *TrueDest = BI->getSuccessor(0);
BasicBlock *FalseDest = (BI->isConditional()) ? BI->getSuccessor(1) : nullptr;
if (TrueDest == BB || FalseDest == BB)
return false;
for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) {
BasicBlock *PredBlock = *PI;
BranchInst *PBI = dyn_cast<BranchInst>(PredBlock->getTerminator());
// Check that we have two conditional branches. If there is a PHI node in
// the common successor, verify that the same value flows in from both
// blocks.
SmallVector<PHINode*, 4> PHIs;
if (!PBI || PBI->isUnconditional() ||
(BI->isConditional() &&
!SafeToMergeTerminators(BI, PBI)) ||
(!BI->isConditional() &&
!isProfitableToFoldUnconditional(BI, PBI, Cond, PHIs)))
continue;
// Determine if the two branches share a common destination.
Instruction::BinaryOps Opc = Instruction::BinaryOpsEnd;
bool InvertPredCond = false;
if (BI->isConditional()) {
if (PBI->getSuccessor(0) == TrueDest)
Opc = Instruction::Or;
else if (PBI->getSuccessor(1) == FalseDest)
Opc = Instruction::And;
else if (PBI->getSuccessor(0) == FalseDest)
Opc = Instruction::And, InvertPredCond = true;
else if (PBI->getSuccessor(1) == TrueDest)
Opc = Instruction::Or, InvertPredCond = true;
else
continue;
} else {
if (PBI->getSuccessor(0) != TrueDest && PBI->getSuccessor(1) != TrueDest)
continue;
}
DEBUG(dbgs() << "FOLDING BRANCH TO COMMON DEST:\n" << *PBI << *BB);
IRBuilder<> Builder(PBI);
// If we need to invert the condition in the pred block to match, do so now.
if (InvertPredCond) {
Value *NewCond = PBI->getCondition();
if (NewCond->hasOneUse() && isa<CmpInst>(NewCond)) {
CmpInst *CI = cast<CmpInst>(NewCond);
CI->setPredicate(CI->getInversePredicate());
} else {
NewCond = Builder.CreateNot(NewCond,
PBI->getCondition()->getName()+".not");
}
PBI->setCondition(NewCond);
PBI->swapSuccessors();
}
// If we have bonus instructions, clone them into the predecessor block.
// Note that there may be multiple predecessor blocks, so we cannot move
// bonus instructions to a predecessor block.
ValueToValueMapTy VMap; // maps original values to cloned values
// We already make sure Cond is the last instruction before BI. Therefore,
// all instructions before Cond other than DbgInfoIntrinsic are bonus
// instructions.
for (auto BonusInst = BB->begin(); Cond != BonusInst; ++BonusInst) {
if (isa<DbgInfoIntrinsic>(BonusInst))
continue;
Instruction *NewBonusInst = BonusInst->clone();
RemapInstruction(NewBonusInst, VMap,
RF_NoModuleLevelChanges | RF_IgnoreMissingEntries);
VMap[BonusInst] = NewBonusInst;
// If we moved a load, we cannot any longer claim any knowledge about
// its potential value. The previous information might have been valid
// only given the branch precondition.
// For an analogous reason, we must also drop all the metadata whose
// semantics we don't understand.
NewBonusInst->dropUnknownMetadata(LLVMContext::MD_dbg);
PredBlock->getInstList().insert(PBI, NewBonusInst);
NewBonusInst->takeName(BonusInst);
BonusInst->setName(BonusInst->getName() + ".old");
}
// Clone Cond into the predecessor basic block, and or/and the
// two conditions together.
Instruction *New = Cond->clone();
RemapInstruction(New, VMap,
RF_NoModuleLevelChanges | RF_IgnoreMissingEntries);
PredBlock->getInstList().insert(PBI, New);
New->takeName(Cond);
Cond->setName(New->getName() + ".old");
if (BI->isConditional()) {
Instruction *NewCond =
cast<Instruction>(Builder.CreateBinOp(Opc, PBI->getCondition(),
New, "or.cond"));
PBI->setCondition(NewCond);
uint64_t PredTrueWeight, PredFalseWeight, SuccTrueWeight, SuccFalseWeight;
bool PredHasWeights = ExtractBranchMetadata(PBI, PredTrueWeight,
PredFalseWeight);
bool SuccHasWeights = ExtractBranchMetadata(BI, SuccTrueWeight,
SuccFalseWeight);
SmallVector<uint64_t, 8> NewWeights;
if (PBI->getSuccessor(0) == BB) {
if (PredHasWeights && SuccHasWeights) {
// PBI: br i1 %x, BB, FalseDest
// BI: br i1 %y, TrueDest, FalseDest
//TrueWeight is TrueWeight for PBI * TrueWeight for BI.
NewWeights.push_back(PredTrueWeight * SuccTrueWeight);
//FalseWeight is FalseWeight for PBI * TotalWeight for BI +
// TrueWeight for PBI * FalseWeight for BI.
// We assume that total weights of a BranchInst can fit into 32 bits.
// Therefore, we will not have overflow using 64-bit arithmetic.
NewWeights.push_back(PredFalseWeight * (SuccFalseWeight +
SuccTrueWeight) + PredTrueWeight * SuccFalseWeight);
}
AddPredecessorToBlock(TrueDest, PredBlock, BB);
PBI->setSuccessor(0, TrueDest);
}
if (PBI->getSuccessor(1) == BB) {
if (PredHasWeights && SuccHasWeights) {
// PBI: br i1 %x, TrueDest, BB
// BI: br i1 %y, TrueDest, FalseDest
//TrueWeight is TrueWeight for PBI * TotalWeight for BI +
// FalseWeight for PBI * TrueWeight for BI.
NewWeights.push_back(PredTrueWeight * (SuccFalseWeight +
SuccTrueWeight) + PredFalseWeight * SuccTrueWeight);
//FalseWeight is FalseWeight for PBI * FalseWeight for BI.
NewWeights.push_back(PredFalseWeight * SuccFalseWeight);
}
AddPredecessorToBlock(FalseDest, PredBlock, BB);
PBI->setSuccessor(1, FalseDest);
}
if (NewWeights.size() == 2) {
// Halve the weights if any of them cannot fit in an uint32_t
FitWeights(NewWeights);
SmallVector<uint32_t, 8> MDWeights(NewWeights.begin(),NewWeights.end());
PBI->setMetadata(LLVMContext::MD_prof,
MDBuilder(BI->getContext()).
createBranchWeights(MDWeights));
} else
PBI->setMetadata(LLVMContext::MD_prof, nullptr);
} else {
// Update PHI nodes in the common successors.
for (unsigned i = 0, e = PHIs.size(); i != e; ++i) {
ConstantInt *PBI_C = cast<ConstantInt>(
PHIs[i]->getIncomingValueForBlock(PBI->getParent()));
assert(PBI_C->getType()->isIntegerTy(1));
Instruction *MergedCond = nullptr;
if (PBI->getSuccessor(0) == TrueDest) {
// Create (PBI_Cond and PBI_C) or (!PBI_Cond and BI_Value)
// PBI_C is true: PBI_Cond or (!PBI_Cond and BI_Value)
// is false: !PBI_Cond and BI_Value
Instruction *NotCond =
cast<Instruction>(Builder.CreateNot(PBI->getCondition(),
"not.cond"));
MergedCond =
cast<Instruction>(Builder.CreateBinOp(Instruction::And,
NotCond, New,
"and.cond"));
if (PBI_C->isOne())
MergedCond =
cast<Instruction>(Builder.CreateBinOp(Instruction::Or,
PBI->getCondition(), MergedCond,
"or.cond"));
} else {
// Create (PBI_Cond and BI_Value) or (!PBI_Cond and PBI_C)
// PBI_C is true: (PBI_Cond and BI_Value) or (!PBI_Cond)
// is false: PBI_Cond and BI_Value
MergedCond =
cast<Instruction>(Builder.CreateBinOp(Instruction::And,
PBI->getCondition(), New,
"and.cond"));
if (PBI_C->isOne()) {
Instruction *NotCond =
cast<Instruction>(Builder.CreateNot(PBI->getCondition(),
"not.cond"));
MergedCond =
cast<Instruction>(Builder.CreateBinOp(Instruction::Or,
NotCond, MergedCond,
"or.cond"));
}
}
// Update PHI Node.
PHIs[i]->setIncomingValue(PHIs[i]->getBasicBlockIndex(PBI->getParent()),
MergedCond);
}
// Change PBI from Conditional to Unconditional.
BranchInst *New_PBI = BranchInst::Create(TrueDest, PBI);
EraseTerminatorInstAndDCECond(PBI);
PBI = New_PBI;
}
// TODO: If BB is reachable from all paths through PredBlock, then we
// could replace PBI's branch probabilities with BI's.
// Copy any debug value intrinsics into the end of PredBlock.
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
if (isa<DbgInfoIntrinsic>(*I))
I->clone()->insertBefore(PBI);
return true;
}
return false;
}
/// If we have a conditional branch as a predecessor of another block,
/// this function tries to simplify it. We know
/// that PBI and BI are both conditional branches, and BI is in one of the
/// successor blocks of PBI - PBI branches to BI.
static bool SimplifyCondBranchToCondBranch(BranchInst *PBI, BranchInst *BI) {
assert(PBI->isConditional() && BI->isConditional());
BasicBlock *BB = BI->getParent();
// If this block ends with a branch instruction, and if there is a
// predecessor that ends on a branch of the same condition, make
// this conditional branch redundant.
if (PBI->getCondition() == BI->getCondition() &&
PBI->getSuccessor(0) != PBI->getSuccessor(1)) {
// Okay, the outcome of this conditional branch is statically
// knowable. If this block had a single pred, handle specially.
if (BB->getSinglePredecessor()) {
// Turn this into a branch on constant.
bool CondIsTrue = PBI->getSuccessor(0) == BB;
BI->setCondition(ConstantInt::get(Type::getInt1Ty(BB->getContext()),
CondIsTrue));
return true; // Nuke the branch on constant.
}
// Otherwise, if there are multiple predecessors, insert a PHI that merges
// in the constant and simplify the block result. Subsequent passes of
// simplifycfg will thread the block.
if (BlockIsSimpleEnoughToThreadThrough(BB)) {
pred_iterator PB = pred_begin(BB), PE = pred_end(BB);
PHINode *NewPN = PHINode::Create(Type::getInt1Ty(BB->getContext()),
std::distance(PB, PE),
BI->getCondition()->getName() + ".pr",
BB->begin());
// Okay, we're going to insert the PHI node. Since PBI is not the only
// predecessor, compute the PHI'd conditional value for all of the preds.
// Any predecessor where the condition is not computable we keep symbolic.
for (pred_iterator PI = PB; PI != PE; ++PI) {
BasicBlock *P = *PI;
if ((PBI = dyn_cast<BranchInst>(P->getTerminator())) &&
PBI != BI && PBI->isConditional() &&
PBI->getCondition() == BI->getCondition() &&
PBI->getSuccessor(0) != PBI->getSuccessor(1)) {
bool CondIsTrue = PBI->getSuccessor(0) == BB;
NewPN->addIncoming(ConstantInt::get(Type::getInt1Ty(BB->getContext()),
CondIsTrue), P);
} else {
NewPN->addIncoming(BI->getCondition(), P);
}
}
BI->setCondition(NewPN);
return true;
}
}
// If this is a conditional branch in an empty block, and if any
// predecessors are a conditional branch to one of our destinations,
// fold the conditions into logical ops and one cond br.
BasicBlock::iterator BBI = BB->begin();
// Ignore dbg intrinsics.
while (isa<DbgInfoIntrinsic>(BBI))
++BBI;
if (&*BBI != BI)
return false;
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(BI->getCondition()))
if (CE->canTrap())
return false;
int PBIOp, BIOp;
if (PBI->getSuccessor(0) == BI->getSuccessor(0))
PBIOp = BIOp = 0;
else if (PBI->getSuccessor(0) == BI->getSuccessor(1))
PBIOp = 0, BIOp = 1;
else if (PBI->getSuccessor(1) == BI->getSuccessor(0))
PBIOp = 1, BIOp = 0;
else if (PBI->getSuccessor(1) == BI->getSuccessor(1))
PBIOp = BIOp = 1;
else
return false;
// Check to make sure that the other destination of this branch
// isn't BB itself. If so, this is an infinite loop that will
// keep getting unwound.
if (PBI->getSuccessor(PBIOp) == BB)
return false;
// Do not perform this transformation if it would require
// insertion of a large number of select instructions. For targets
// without predication/cmovs, this is a big pessimization.
// Also do not perform this transformation if any phi node in the common
// destination block can trap when reached by BB or PBB (PR17073). In that
// case, it would be unsafe to hoist the operation into a select instruction.
BasicBlock *CommonDest = PBI->getSuccessor(PBIOp);
unsigned NumPhis = 0;
for (BasicBlock::iterator II = CommonDest->begin();
isa<PHINode>(II); ++II, ++NumPhis) {
if (NumPhis > 2) // Disable this xform.
return false;
PHINode *PN = cast<PHINode>(II);
Value *BIV = PN->getIncomingValueForBlock(BB);
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(BIV))
if (CE->canTrap())
return false;
unsigned PBBIdx = PN->getBasicBlockIndex(PBI->getParent());
Value *PBIV = PN->getIncomingValue(PBBIdx);
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(PBIV))
if (CE->canTrap())
return false;
}
// Finally, if everything is ok, fold the branches to logical ops.
BasicBlock *OtherDest = BI->getSuccessor(BIOp ^ 1);
DEBUG(dbgs() << "FOLDING BRs:" << *PBI->getParent()
<< "AND: " << *BI->getParent());
// If OtherDest *is* BB, then BB is a basic block with a single conditional
// branch in it, where one edge (OtherDest) goes back to itself but the other
// exits. We don't *know* that the program avoids the infinite loop
// (even though that seems likely). If we do this xform naively, we'll end up
// recursively unpeeling the loop. Since we know that (after the xform is
// done) that the block *is* infinite if reached, we just make it an obviously
// infinite loop with no cond branch.
if (OtherDest == BB) {
// Insert it at the end of the function, because it's either code,
// or it won't matter if it's hot. :)
BasicBlock *InfLoopBlock = BasicBlock::Create(BB->getContext(),
"infloop", BB->getParent());
BranchInst::Create(InfLoopBlock, InfLoopBlock);
OtherDest = InfLoopBlock;
}
DEBUG(dbgs() << *PBI->getParent()->getParent());
// BI may have other predecessors. Because of this, we leave
// it alone, but modify PBI.
// Make sure we get to CommonDest on True&True directions.
Value *PBICond = PBI->getCondition();
IRBuilder<true, NoFolder> Builder(PBI);
if (PBIOp)
PBICond = Builder.CreateNot(PBICond, PBICond->getName()+".not");
Value *BICond = BI->getCondition();
if (BIOp)
BICond = Builder.CreateNot(BICond, BICond->getName()+".not");
// Merge the conditions.
Value *Cond = Builder.CreateOr(PBICond, BICond, "brmerge");
// Modify PBI to branch on the new condition to the new dests.
PBI->setCondition(Cond);
PBI->setSuccessor(0, CommonDest);
PBI->setSuccessor(1, OtherDest);
// Update branch weight for PBI.
uint64_t PredTrueWeight, PredFalseWeight, SuccTrueWeight, SuccFalseWeight;
bool PredHasWeights = ExtractBranchMetadata(PBI, PredTrueWeight,
PredFalseWeight);
bool SuccHasWeights = ExtractBranchMetadata(BI, SuccTrueWeight,
SuccFalseWeight);
if (PredHasWeights && SuccHasWeights) {
uint64_t PredCommon = PBIOp ? PredFalseWeight : PredTrueWeight;
uint64_t PredOther = PBIOp ?PredTrueWeight : PredFalseWeight;
uint64_t SuccCommon = BIOp ? SuccFalseWeight : SuccTrueWeight;
uint64_t SuccOther = BIOp ? SuccTrueWeight : SuccFalseWeight;
// The weight to CommonDest should be PredCommon * SuccTotal +
// PredOther * SuccCommon.
// The weight to OtherDest should be PredOther * SuccOther.
uint64_t NewWeights[2] = {PredCommon * (SuccCommon + SuccOther) +
PredOther * SuccCommon,
PredOther * SuccOther};
// Halve the weights if any of them cannot fit in an uint32_t
FitWeights(NewWeights);
PBI->setMetadata(LLVMContext::MD_prof,
MDBuilder(BI->getContext())
.createBranchWeights(NewWeights[0], NewWeights[1]));
}
// OtherDest may have phi nodes. If so, add an entry from PBI's
// block that are identical to the entries for BI's block.
AddPredecessorToBlock(OtherDest, PBI->getParent(), BB);
// We know that the CommonDest already had an edge from PBI to
// it. If it has PHIs though, the PHIs may have different
// entries for BB and PBI's BB. If so, insert a select to make
// them agree.
PHINode *PN;
for (BasicBlock::iterator II = CommonDest->begin();
(PN = dyn_cast<PHINode>(II)); ++II) {
Value *BIV = PN->getIncomingValueForBlock(BB);
unsigned PBBIdx = PN->getBasicBlockIndex(PBI->getParent());
Value *PBIV = PN->getIncomingValue(PBBIdx);
if (BIV != PBIV) {
// Insert a select in PBI to pick the right value.
Value *NV = cast<SelectInst>
(Builder.CreateSelect(PBICond, PBIV, BIV, PBIV->getName()+".mux"));
PN->setIncomingValue(PBBIdx, NV);
}
}
DEBUG(dbgs() << "INTO: " << *PBI->getParent());
DEBUG(dbgs() << *PBI->getParent()->getParent());
// This basic block is probably dead. We know it has at least
// one fewer predecessor.
return true;
}
// Simplifies a terminator by replacing it with a branch to TrueBB if Cond is
// true or to FalseBB if Cond is false.
// Takes care of updating the successors and removing the old terminator.
// Also makes sure not to introduce new successors by assuming that edges to
// non-successor TrueBBs and FalseBBs aren't reachable.
static bool SimplifyTerminatorOnSelect(TerminatorInst *OldTerm, Value *Cond,
BasicBlock *TrueBB, BasicBlock *FalseBB,
uint32_t TrueWeight,
uint32_t FalseWeight){
// Remove any superfluous successor edges from the CFG.
// First, figure out which successors to preserve.
// If TrueBB and FalseBB are equal, only try to preserve one copy of that
// successor.
BasicBlock *KeepEdge1 = TrueBB;
BasicBlock *KeepEdge2 = TrueBB != FalseBB ? FalseBB : nullptr;
// Then remove the rest.
for (unsigned I = 0, E = OldTerm->getNumSuccessors(); I != E; ++I) {
BasicBlock *Succ = OldTerm->getSuccessor(I);
// Make sure only to keep exactly one copy of each edge.
if (Succ == KeepEdge1)
KeepEdge1 = nullptr;
else if (Succ == KeepEdge2)
KeepEdge2 = nullptr;
else
Succ->removePredecessor(
OldTerm->getParent(),
/*DontDeleteUselessPHIs=*/true // HLSL Change: foward port LLVM fix
);
}
IRBuilder<> Builder(OldTerm);
Builder.SetCurrentDebugLocation(OldTerm->getDebugLoc());
// Insert an appropriate new terminator.
if (!KeepEdge1 && !KeepEdge2) {
if (TrueBB == FalseBB)
// We were only looking for one successor, and it was present.
// Create an unconditional branch to it.
Builder.CreateBr(TrueBB);
else {
// We found both of the successors we were looking for.
// Create a conditional branch sharing the condition of the select.
BranchInst *NewBI = Builder.CreateCondBr(Cond, TrueBB, FalseBB);
if (TrueWeight != FalseWeight)
NewBI->setMetadata(LLVMContext::MD_prof,
MDBuilder(OldTerm->getContext()).
createBranchWeights(TrueWeight, FalseWeight));
}
} else if (KeepEdge1 && (KeepEdge2 || TrueBB == FalseBB)) {
// Neither of the selected blocks were successors, so this
// terminator must be unreachable.
new UnreachableInst(OldTerm->getContext(), OldTerm);
} else {
// One of the selected values was a successor, but the other wasn't.
// Insert an unconditional branch to the one that was found;
// the edge to the one that wasn't must be unreachable.
if (!KeepEdge1)
// Only TrueBB was found.
Builder.CreateBr(TrueBB);
else
// Only FalseBB was found.
Builder.CreateBr(FalseBB);
}
EraseTerminatorInstAndDCECond(OldTerm);
return true;
}
// Replaces
// (switch (select cond, X, Y)) on constant X, Y
// with a branch - conditional if X and Y lead to distinct BBs,
// unconditional otherwise.
static bool SimplifySwitchOnSelect(SwitchInst *SI, SelectInst *Select) {
// Check for constant integer values in the select.
ConstantInt *TrueVal = dyn_cast<ConstantInt>(Select->getTrueValue());
ConstantInt *FalseVal = dyn_cast<ConstantInt>(Select->getFalseValue());
if (!TrueVal || !FalseVal)
return false;
// Find the relevant condition and destinations.
Value *Condition = Select->getCondition();
BasicBlock *TrueBB = SI->findCaseValue(TrueVal).getCaseSuccessor();
BasicBlock *FalseBB = SI->findCaseValue(FalseVal).getCaseSuccessor();
// Get weight for TrueBB and FalseBB.
uint32_t TrueWeight = 0, FalseWeight = 0;
SmallVector<uint64_t, 8> Weights;
bool HasWeights = HasBranchWeights(SI);
if (HasWeights) {
GetBranchWeights(SI, Weights);
if (Weights.size() == 1 + SI->getNumCases()) {
TrueWeight = (uint32_t)Weights[SI->findCaseValue(TrueVal).
getSuccessorIndex()];
FalseWeight = (uint32_t)Weights[SI->findCaseValue(FalseVal).
getSuccessorIndex()];
}
}
// Perform the actual simplification.
return SimplifyTerminatorOnSelect(SI, Condition, TrueBB, FalseBB,
TrueWeight, FalseWeight);
}
// Replaces
// (indirectbr (select cond, blockaddress(@fn, BlockA),
// blockaddress(@fn, BlockB)))
// with
// (br cond, BlockA, BlockB).
static bool SimplifyIndirectBrOnSelect(IndirectBrInst *IBI, SelectInst *SI) {
// Check that both operands of the select are block addresses.
BlockAddress *TBA = dyn_cast<BlockAddress>(SI->getTrueValue());
BlockAddress *FBA = dyn_cast<BlockAddress>(SI->getFalseValue());
if (!TBA || !FBA)
return false;
// Extract the actual blocks.
BasicBlock *TrueBB = TBA->getBasicBlock();
BasicBlock *FalseBB = FBA->getBasicBlock();
// Perform the actual simplification.
return SimplifyTerminatorOnSelect(IBI, SI->getCondition(), TrueBB, FalseBB,
0, 0);
}
/// This is called when we find an icmp instruction
/// (a seteq/setne with a constant) as the only instruction in a
/// block that ends with an uncond branch. We are looking for a very specific
/// pattern that occurs when "A == 1 || A == 2 || A == 3" gets simplified. In
/// this case, we merge the first two "or's of icmp" into a switch, but then the
/// default value goes to an uncond block with a seteq in it, we get something
/// like:
///
/// switch i8 %A, label %DEFAULT [ i8 1, label %end i8 2, label %end ]
/// DEFAULT:
/// %tmp = icmp eq i8 %A, 92
/// br label %end
/// end:
/// ... = phi i1 [ true, %entry ], [ %tmp, %DEFAULT ], [ true, %entry ]
///
/// We prefer to split the edge to 'end' so that there is a true/false entry to
/// the PHI, merging the third icmp into the switch.
static bool TryToSimplifyUncondBranchWithICmpInIt(
ICmpInst *ICI, IRBuilder<> &Builder, const DataLayout &DL,
const TargetTransformInfo &TTI, unsigned BonusInstThreshold,
AssumptionCache *AC) {
BasicBlock *BB = ICI->getParent();
// If the block has any PHIs in it or the icmp has multiple uses, it is too
// complex.
if (isa<PHINode>(BB->begin()) || !ICI->hasOneUse()) return false;
Value *V = ICI->getOperand(0);
ConstantInt *Cst = cast<ConstantInt>(ICI->getOperand(1));
// The pattern we're looking for is where our only predecessor is a switch on
// 'V' and this block is the default case for the switch. In this case we can
// fold the compared value into the switch to simplify things.
BasicBlock *Pred = BB->getSinglePredecessor();
if (!Pred || !isa<SwitchInst>(Pred->getTerminator())) return false;
SwitchInst *SI = cast<SwitchInst>(Pred->getTerminator());
if (SI->getCondition() != V)
return false;
// If BB is reachable on a non-default case, then we simply know the value of
// V in this block. Substitute it and constant fold the icmp instruction
// away.
if (SI->getDefaultDest() != BB) {
ConstantInt *VVal = SI->findCaseDest(BB);
assert(VVal && "Should have a unique destination value");
ICI->setOperand(0, VVal);
if (Value *V = SimplifyInstruction(ICI, DL)) {
ICI->replaceAllUsesWith(V);
ICI->eraseFromParent();
}
// BB is now empty, so it is likely to simplify away.
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
}
// Ok, the block is reachable from the default dest. If the constant we're
// comparing exists in one of the other edges, then we can constant fold ICI
// and zap it.
if (SI->findCaseValue(Cst) != SI->case_default()) {
Value *V;
if (ICI->getPredicate() == ICmpInst::ICMP_EQ)
V = ConstantInt::getFalse(BB->getContext());
else
V = ConstantInt::getTrue(BB->getContext());
ICI->replaceAllUsesWith(V);
ICI->eraseFromParent();
// BB is now empty, so it is likely to simplify away.
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
}
// The use of the icmp has to be in the 'end' block, by the only PHI node in
// the block.
BasicBlock *SuccBlock = BB->getTerminator()->getSuccessor(0);
PHINode *PHIUse = dyn_cast<PHINode>(ICI->user_back());
if (PHIUse == nullptr || PHIUse != &SuccBlock->front() ||
isa<PHINode>(++BasicBlock::iterator(PHIUse)))
return false;
// If the icmp is a SETEQ, then the default dest gets false, the new edge gets
// true in the PHI.
Constant *DefaultCst = ConstantInt::getTrue(BB->getContext());
Constant *NewCst = ConstantInt::getFalse(BB->getContext());
if (ICI->getPredicate() == ICmpInst::ICMP_EQ)
std::swap(DefaultCst, NewCst);
// Replace ICI (which is used by the PHI for the default value) with true or
// false depending on if it is EQ or NE.
ICI->replaceAllUsesWith(DefaultCst);
ICI->eraseFromParent();
// Okay, the switch goes to this block on a default value. Add an edge from
// the switch to the merge point on the compared value.
BasicBlock *NewBB = BasicBlock::Create(BB->getContext(), "switch.edge",
BB->getParent(), BB);
SmallVector<uint64_t, 8> Weights;
bool HasWeights = HasBranchWeights(SI);
if (HasWeights) {
GetBranchWeights(SI, Weights);
if (Weights.size() == 1 + SI->getNumCases()) {
// Split weight for default case to case for "Cst".
Weights[0] = (Weights[0]+1) >> 1;
Weights.push_back(Weights[0]);
SmallVector<uint32_t, 8> MDWeights(Weights.begin(), Weights.end());
SI->setMetadata(LLVMContext::MD_prof,
MDBuilder(SI->getContext()).
createBranchWeights(MDWeights));
}
}
SI->addCase(Cst, NewBB);
// NewBB branches to the phi block, add the uncond branch and the phi entry.
Builder.SetInsertPoint(NewBB);
Builder.SetCurrentDebugLocation(SI->getDebugLoc());
Builder.CreateBr(SuccBlock);
PHIUse->addIncoming(NewCst, NewBB);
return true;
}
#if 0 // HLSL Change Begins. This will not help for hlsl.
/// The specified branch is a conditional branch.
/// Check to see if it is branching on an or/and chain of icmp instructions, and
/// fold it into a switch instruction if so.
static bool SimplifyBranchOnICmpChain(BranchInst *BI, IRBuilder<> &Builder,
const DataLayout &DL) {
Instruction *Cond = dyn_cast<Instruction>(BI->getCondition());
if (!Cond) return false;
// Change br (X == 0 | X == 1), T, F into a switch instruction.
// If this is a bunch of seteq's or'd together, or if it's a bunch of
// 'setne's and'ed together, collect them.
// Try to gather values from a chain of and/or to be turned into a switch
ConstantComparesGatherer ConstantCompare(Cond, DL);
// Unpack the result
SmallVectorImpl<ConstantInt*> &Values = ConstantCompare.Vals;
Value *CompVal = ConstantCompare.CompValue;
unsigned UsedICmps = ConstantCompare.UsedICmps;
Value *ExtraCase = ConstantCompare.Extra;
// If we didn't have a multiply compared value, fail.
if (!CompVal) return false;
// Avoid turning single icmps into a switch.
if (UsedICmps <= 1)
return false;
bool TrueWhenEqual = (Cond->getOpcode() == Instruction::Or);
// There might be duplicate constants in the list, which the switch
// instruction can't handle, remove them now.
array_pod_sort(Values.begin(), Values.end(), ConstantIntSortPredicate);
Values.erase(std::unique(Values.begin(), Values.end()), Values.end());
// If Extra was used, we require at least two switch values to do the
// transformation. A switch with one value is just an cond branch.
if (ExtraCase && Values.size() < 2) return false;
// TODO: Preserve branch weight metadata, similarly to how
// FoldValueComparisonIntoPredecessors preserves it.
// Figure out which block is which destination.
BasicBlock *DefaultBB = BI->getSuccessor(1);
BasicBlock *EdgeBB = BI->getSuccessor(0);
if (!TrueWhenEqual) std::swap(DefaultBB, EdgeBB);
BasicBlock *BB = BI->getParent();
DEBUG(dbgs() << "Converting 'icmp' chain with " << Values.size()
<< " cases into SWITCH. BB is:\n" << *BB);
// If there are any extra values that couldn't be folded into the switch
// then we evaluate them with an explicit branch first. Split the block
// right before the condbr to handle it.
if (ExtraCase) {
BasicBlock *NewBB = BB->splitBasicBlock(BI, "switch.early.test");
// Remove the uncond branch added to the old block.
TerminatorInst *OldTI = BB->getTerminator();
Builder.SetInsertPoint(OldTI);
if (TrueWhenEqual)
Builder.CreateCondBr(ExtraCase, EdgeBB, NewBB);
else
Builder.CreateCondBr(ExtraCase, NewBB, EdgeBB);
OldTI->eraseFromParent();
// If there are PHI nodes in EdgeBB, then we need to add a new entry to them
// for the edge we just added.
AddPredecessorToBlock(EdgeBB, BB, NewBB);
DEBUG(dbgs() << " ** 'icmp' chain unhandled condition: " << *ExtraCase
<< "\nEXTRABB = " << *BB);
BB = NewBB;
}
Builder.SetInsertPoint(BI);
// Convert pointer to int before we switch.
if (CompVal->getType()->isPointerTy()) {
CompVal = Builder.CreatePtrToInt(
CompVal, DL.getIntPtrType(CompVal->getType()), "magicptr");
}
// Create the new switch instruction now.
SwitchInst *New = Builder.CreateSwitch(CompVal, DefaultBB, Values.size());
// Add all of the 'cases' to the switch instruction.
for (unsigned i = 0, e = Values.size(); i != e; ++i)
New->addCase(Values[i], EdgeBB);
// We added edges from PI to the EdgeBB. As such, if there were any
// PHI nodes in EdgeBB, they need entries to be added corresponding to
// the number of edges added.
for (BasicBlock::iterator BBI = EdgeBB->begin();
isa<PHINode>(BBI); ++BBI) {
PHINode *PN = cast<PHINode>(BBI);
Value *InVal = PN->getIncomingValueForBlock(BB);
for (unsigned i = 0, e = Values.size()-1; i != e; ++i)
PN->addIncoming(InVal, BB);
}
// Erase the old branch instruction.
EraseTerminatorInstAndDCECond(BI);
DEBUG(dbgs() << " ** 'icmp' chain result is:\n" << *BB << '\n');
return true;
}
#endif // HLSL Change Ends
bool SimplifyCFGOpt::SimplifyResume(ResumeInst *RI, IRBuilder<> &Builder) {
// If this is a trivial landing pad that just continues unwinding the caught
// exception then zap the landing pad, turning its invokes into calls.
BasicBlock *BB = RI->getParent();
LandingPadInst *LPInst = dyn_cast<LandingPadInst>(BB->getFirstNonPHI());
if (RI->getValue() != LPInst)
// Not a landing pad, or the resume is not unwinding the exception that
// caused control to branch here.
return false;
// Check that there are no other instructions except for debug intrinsics.
BasicBlock::iterator I = LPInst, E = RI;
while (++I != E)
if (!isa<DbgInfoIntrinsic>(I))
return false;
// Turn all invokes that unwind here into calls and delete the basic block.
for (pred_iterator PI = pred_begin(BB), PE = pred_end(BB); PI != PE;) {
InvokeInst *II = cast<InvokeInst>((*PI++)->getTerminator());
SmallVector<Value*, 8> Args(II->op_begin(), II->op_end() - 3);
// Insert a call instruction before the invoke.
CallInst *Call = CallInst::Create(II->getCalledValue(), Args, "", II);
Call->takeName(II);
Call->setCallingConv(II->getCallingConv());
Call->setAttributes(II->getAttributes());
Call->setDebugLoc(II->getDebugLoc());
// Anything that used the value produced by the invoke instruction now uses
// the value produced by the call instruction. Note that we do this even
// for void functions and calls with no uses so that the callgraph edge is
// updated.
II->replaceAllUsesWith(Call);
BB->removePredecessor(II->getParent());
// Insert a branch to the normal destination right before the invoke.
BranchInst::Create(II->getNormalDest(), II);
// Finally, delete the invoke instruction!
II->eraseFromParent();
}
// The landingpad is now unreachable. Zap it.
BB->eraseFromParent();
return true;
}
bool SimplifyCFGOpt::SimplifyReturn(ReturnInst *RI, IRBuilder<> &Builder) {
BasicBlock *BB = RI->getParent();
if (!BB->getFirstNonPHIOrDbg()->isTerminator()) return false;
// Find predecessors that end with branches.
SmallVector<BasicBlock*, 8> UncondBranchPreds;
SmallVector<BranchInst*, 8> CondBranchPreds;
for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) {
BasicBlock *P = *PI;
TerminatorInst *PTI = P->getTerminator();
if (BranchInst *BI = dyn_cast<BranchInst>(PTI)) {
if (BI->isUnconditional())
UncondBranchPreds.push_back(P);
else
CondBranchPreds.push_back(BI);
}
}
// If we found some, do the transformation!
if (!UncondBranchPreds.empty() && DupRet) {
while (!UncondBranchPreds.empty()) {
BasicBlock *Pred = UncondBranchPreds.pop_back_val();
DEBUG(dbgs() << "FOLDING: " << *BB
<< "INTO UNCOND BRANCH PRED: " << *Pred);
(void)FoldReturnIntoUncondBranch(RI, BB, Pred);
}
// If we eliminated all predecessors of the block, delete the block now.
if (pred_empty(BB))
// We know there are no successors, so just nuke the block.
BB->eraseFromParent();
return true;
}
// Check out all of the conditional branches going to this return
// instruction. If any of them just select between returns, change the
// branch itself into a select/return pair.
while (!CondBranchPreds.empty()) {
BranchInst *BI = CondBranchPreds.pop_back_val();
// Check to see if the non-BB successor is also a return block.
if (isa<ReturnInst>(BI->getSuccessor(0)->getTerminator()) &&
isa<ReturnInst>(BI->getSuccessor(1)->getTerminator()) &&
SimplifyCondBranchToTwoReturns(BI, Builder))
return true;
}
return false;
}
bool SimplifyCFGOpt::SimplifyUnreachable(UnreachableInst *UI) {
BasicBlock *BB = UI->getParent();
bool Changed = false;
// If there are any instructions immediately before the unreachable that can
// be removed, do so.
while (UI != BB->begin()) {
BasicBlock::iterator BBI = UI;
--BBI;
// Do not delete instructions that can have side effects which might cause
// the unreachable to not be reachable; specifically, calls and volatile
// operations may have this effect.
if (isa<CallInst>(BBI) && !isa<DbgInfoIntrinsic>(BBI)) break;
if (BBI->mayHaveSideEffects()) {
if (StoreInst *SI = dyn_cast<StoreInst>(BBI)) {
if (SI->isVolatile())
break;
} else if (LoadInst *LI = dyn_cast<LoadInst>(BBI)) {
if (LI->isVolatile())
break;
} else if (AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(BBI)) {
if (RMWI->isVolatile())
break;
} else if (AtomicCmpXchgInst *CXI = dyn_cast<AtomicCmpXchgInst>(BBI)) {
if (CXI->isVolatile())
break;
} else if (!isa<FenceInst>(BBI) && !isa<VAArgInst>(BBI) &&
!isa<LandingPadInst>(BBI)) {
break;
}
// Note that deleting LandingPad's here is in fact okay, although it
// involves a bit of subtle reasoning. If this inst is a LandingPad,
// all the predecessors of this block will be the unwind edges of Invokes,
// and we can therefore guarantee this block will be erased.
}
// Delete this instruction (any uses are guaranteed to be dead)
if (!BBI->use_empty())
BBI->replaceAllUsesWith(UndefValue::get(BBI->getType()));
BBI->eraseFromParent();
Changed = true;
}
// If the unreachable instruction is the first in the block, take a gander
// at all of the predecessors of this instruction, and simplify them.
if (&BB->front() != UI) return Changed;
SmallVector<BasicBlock*, 8> Preds(pred_begin(BB), pred_end(BB));
for (unsigned i = 0, e = Preds.size(); i != e; ++i) {
TerminatorInst *TI = Preds[i]->getTerminator();
IRBuilder<> Builder(TI);
if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
if (BI->isUnconditional()) {
if (BI->getSuccessor(0) == BB) {
new UnreachableInst(TI->getContext(), TI);
TI->eraseFromParent();
Changed = true;
}
} else {
if (BI->getSuccessor(0) == BB) {
Builder.CreateBr(BI->getSuccessor(1));
EraseTerminatorInstAndDCECond(BI);
} else if (BI->getSuccessor(1) == BB) {
Builder.CreateBr(BI->getSuccessor(0));
EraseTerminatorInstAndDCECond(BI);
Changed = true;
}
}
} else if (SwitchInst *SI = dyn_cast<SwitchInst>(TI)) {
for (SwitchInst::CaseIt i = SI->case_begin(), e = SI->case_end();
i != e; ++i)
if (i.getCaseSuccessor() == BB) {
BB->removePredecessor(SI->getParent());
SI->removeCase(i);
--i; --e;
Changed = true;
}
} else if (InvokeInst *II = dyn_cast<InvokeInst>(TI)) {
if (II->getUnwindDest() == BB) {
// Convert the invoke to a call instruction. This would be a good
// place to note that the call does not throw though.
BranchInst *BI = Builder.CreateBr(II->getNormalDest());
II->removeFromParent(); // Take out of symbol table
// Insert the call now...
SmallVector<Value*, 8> Args(II->op_begin(), II->op_end()-3);
Builder.SetInsertPoint(BI);
CallInst *CI = Builder.CreateCall(II->getCalledValue(),
Args, II->getName());
CI->setCallingConv(II->getCallingConv());
CI->setAttributes(II->getAttributes());
// If the invoke produced a value, the call does now instead.
II->replaceAllUsesWith(CI);
delete II;
Changed = true;
}
}
}
// If this block is now dead, remove it.
if (pred_empty(BB) &&
BB != &BB->getParent()->getEntryBlock()) {
// We know there are no successors, so just nuke the block.
BB->eraseFromParent();
return true;
}
return Changed;
}
static bool CasesAreContiguous(SmallVectorImpl<ConstantInt *> &Cases) {
assert(Cases.size() >= 1);
array_pod_sort(Cases.begin(), Cases.end(), ConstantIntSortPredicate);
for (size_t I = 1, E = Cases.size(); I != E; ++I) {
if (Cases[I - 1]->getValue() != Cases[I]->getValue() + 1)
return false;
}
return true;
}
/// Turn a switch with two reachable destinations into an integer range
/// comparison and branch.
static bool TurnSwitchRangeIntoICmp(SwitchInst *SI, IRBuilder<> &Builder) {
assert(SI->getNumCases() > 1 && "Degenerate switch?");
bool HasDefault =
!isa<UnreachableInst>(SI->getDefaultDest()->getFirstNonPHIOrDbg());
// Partition the cases into two sets with different destinations.
BasicBlock *DestA = HasDefault ? SI->getDefaultDest() : nullptr;
BasicBlock *DestB = nullptr;
SmallVector <ConstantInt *, 16> CasesA;
SmallVector <ConstantInt *, 16> CasesB;
for (SwitchInst::CaseIt I : SI->cases()) {
BasicBlock *Dest = I.getCaseSuccessor();
if (!DestA) DestA = Dest;
if (Dest == DestA) {
CasesA.push_back(I.getCaseValue());
continue;
}
if (!DestB) DestB = Dest;
if (Dest == DestB) {
CasesB.push_back(I.getCaseValue());
continue;
}
return false; // More than two destinations.
}
assert(DestA && DestB && "Single-destination switch should have been folded.");
assert(DestA != DestB);
assert(DestB != SI->getDefaultDest());
assert(!CasesB.empty() && "There must be non-default cases.");
assert(!CasesA.empty() || HasDefault);
// Figure out if one of the sets of cases form a contiguous range.
SmallVectorImpl<ConstantInt *> *ContiguousCases = nullptr;
BasicBlock *ContiguousDest = nullptr;
BasicBlock *OtherDest = nullptr;
if (!CasesA.empty() && CasesAreContiguous(CasesA)) {
ContiguousCases = &CasesA;
ContiguousDest = DestA;
OtherDest = DestB;
} else if (CasesAreContiguous(CasesB)) {
ContiguousCases = &CasesB;
ContiguousDest = DestB;
OtherDest = DestA;
} else
return false;
// Start building the compare and branch.
Constant *Offset = ConstantExpr::getNeg(ContiguousCases->back());
Constant *NumCases = ConstantInt::get(Offset->getType(), ContiguousCases->size());
Value *Sub = SI->getCondition();
if (!Offset->isNullValue())
Sub = Builder.CreateAdd(Sub, Offset, Sub->getName() + ".off");
Value *Cmp;
// If NumCases overflowed, then all possible values jump to the successor.
if (NumCases->isNullValue() && !ContiguousCases->empty())
Cmp = ConstantInt::getTrue(SI->getContext());
else
Cmp = Builder.CreateICmpULT(Sub, NumCases, "switch");
BranchInst *NewBI = Builder.CreateCondBr(Cmp, ContiguousDest, OtherDest);
// Update weight for the newly-created conditional branch.
if (HasBranchWeights(SI)) {
SmallVector<uint64_t, 8> Weights;
GetBranchWeights(SI, Weights);
if (Weights.size() == 1 + SI->getNumCases()) {
uint64_t TrueWeight = 0;
uint64_t FalseWeight = 0;
for (size_t I = 0, E = Weights.size(); I != E; ++I) {
if (SI->getSuccessor(I) == ContiguousDest)
TrueWeight += Weights[I];
else
FalseWeight += Weights[I];
}
while (TrueWeight > UINT32_MAX || FalseWeight > UINT32_MAX) {
TrueWeight /= 2;
FalseWeight /= 2;
}
NewBI->setMetadata(LLVMContext::MD_prof,
MDBuilder(SI->getContext()).createBranchWeights(
(uint32_t)TrueWeight, (uint32_t)FalseWeight));
}
}
// Prune obsolete incoming values off the successors' PHI nodes.
for (auto BBI = ContiguousDest->begin(); isa<PHINode>(BBI); ++BBI) {
unsigned PreviousEdges = ContiguousCases->size();
if (ContiguousDest == SI->getDefaultDest()) ++PreviousEdges;
for (unsigned I = 0, E = PreviousEdges - 1; I != E; ++I)
cast<PHINode>(BBI)->removeIncomingValue(SI->getParent());
}
for (auto BBI = OtherDest->begin(); isa<PHINode>(BBI); ++BBI) {
unsigned PreviousEdges = SI->getNumCases() - ContiguousCases->size();
if (OtherDest == SI->getDefaultDest()) ++PreviousEdges;
for (unsigned I = 0, E = PreviousEdges - 1; I != E; ++I)
cast<PHINode>(BBI)->removeIncomingValue(SI->getParent());
}
// Drop the switch.
SI->eraseFromParent();
return true;
}
/// Compute masked bits for the condition of a switch
/// and use it to remove dead cases.
static bool EliminateDeadSwitchCases(SwitchInst *SI, AssumptionCache *AC,
const DataLayout &DL) {
Value *Cond = SI->getCondition();
unsigned Bits = Cond->getType()->getIntegerBitWidth();
APInt KnownZero(Bits, 0), KnownOne(Bits, 0);
computeKnownBits(Cond, KnownZero, KnownOne, DL, 0, AC, SI);
// Gather dead cases.
SmallVector<ConstantInt*, 8> DeadCases;
for (SwitchInst::CaseIt I = SI->case_begin(), E = SI->case_end(); I != E; ++I) {
if ((I.getCaseValue()->getValue() & KnownZero) != 0 ||
(I.getCaseValue()->getValue() & KnownOne) != KnownOne) {
DeadCases.push_back(I.getCaseValue());
DEBUG(dbgs() << "SimplifyCFG: switch case '"
<< I.getCaseValue() << "' is dead.\n");
}
}
SmallVector<uint64_t, 8> Weights;
bool HasWeight = HasBranchWeights(SI);
if (HasWeight) {
GetBranchWeights(SI, Weights);
HasWeight = (Weights.size() == 1 + SI->getNumCases());
}
// Remove dead cases from the switch.
for (unsigned I = 0, E = DeadCases.size(); I != E; ++I) {
SwitchInst::CaseIt Case = SI->findCaseValue(DeadCases[I]);
assert(Case != SI->case_default() &&
"Case was not found. Probably mistake in DeadCases forming.");
if (HasWeight) {
std::swap(Weights[Case.getCaseIndex()+1], Weights.back());
Weights.pop_back();
}
// Prune unused values from PHI nodes.
Case.getCaseSuccessor()->removePredecessor(SI->getParent());
SI->removeCase(Case);
}
if (HasWeight && Weights.size() >= 2) {
SmallVector<uint32_t, 8> MDWeights(Weights.begin(), Weights.end());
SI->setMetadata(LLVMContext::MD_prof,
MDBuilder(SI->getParent()->getContext()).
createBranchWeights(MDWeights));
}
return !DeadCases.empty();
}
/// If BB would be eligible for simplification by
/// TryToSimplifyUncondBranchFromEmptyBlock (i.e. it is empty and terminated
/// by an unconditional branch), look at the phi node for BB in the successor
/// block and see if the incoming value is equal to CaseValue. If so, return
/// the phi node, and set PhiIndex to BB's index in the phi node.
static PHINode *FindPHIForConditionForwarding(ConstantInt *CaseValue,
BasicBlock *BB,
int *PhiIndex) {
if (BB->getFirstNonPHIOrDbg() != BB->getTerminator())
return nullptr; // BB must be empty to be a candidate for simplification.
if (!BB->getSinglePredecessor())
return nullptr; // BB must be dominated by the switch.
BranchInst *Branch = dyn_cast<BranchInst>(BB->getTerminator());
if (!Branch || !Branch->isUnconditional())
return nullptr; // Terminator must be unconditional branch.
BasicBlock *Succ = Branch->getSuccessor(0);
BasicBlock::iterator I = Succ->begin();
while (PHINode *PHI = dyn_cast<PHINode>(I++)) {
int Idx = PHI->getBasicBlockIndex(BB);
assert(Idx >= 0 && "PHI has no entry for predecessor?");
Value *InValue = PHI->getIncomingValue(Idx);
if (InValue != CaseValue) continue;
*PhiIndex = Idx;
return PHI;
}
return nullptr;
}
/// Try to forward the condition of a switch instruction to a phi node
/// dominated by the switch, if that would mean that some of the destination
/// blocks of the switch can be folded away.
/// Returns true if a change is made.
static bool ForwardSwitchConditionToPHI(SwitchInst *SI) {
typedef DenseMap<PHINode*, SmallVector<int,4> > ForwardingNodesMap;
ForwardingNodesMap ForwardingNodes;
for (SwitchInst::CaseIt I = SI->case_begin(), E = SI->case_end(); I != E; ++I) {
ConstantInt *CaseValue = I.getCaseValue();
BasicBlock *CaseDest = I.getCaseSuccessor();
int PhiIndex;
PHINode *PHI = FindPHIForConditionForwarding(CaseValue, CaseDest,
&PhiIndex);
if (!PHI) continue;
ForwardingNodes[PHI].push_back(PhiIndex);
}
bool Changed = false;
for (ForwardingNodesMap::iterator I = ForwardingNodes.begin(),
E = ForwardingNodes.end(); I != E; ++I) {
PHINode *Phi = I->first;
SmallVectorImpl<int> &Indexes = I->second;
if (Indexes.size() < 2) continue;
for (size_t I = 0, E = Indexes.size(); I != E; ++I)
Phi->setIncomingValue(Indexes[I], SI->getCondition());
Changed = true;
}
return Changed;
}
/// Return true if the backend will be able to handle
/// initializing an array of constants like C.
static bool ValidLookupTableConstant(Constant *C) {
if (C->isThreadDependent())
return false;
if (C->isDLLImportDependent())
return false;
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C))
return CE->isGEPWithNoNotionalOverIndexing();
return isa<ConstantFP>(C) ||
isa<ConstantInt>(C) ||
isa<ConstantPointerNull>(C) ||
isa<GlobalValue>(C) ||
isa<UndefValue>(C);
}
/// If V is a Constant, return it. Otherwise, try to look up
/// its constant value in ConstantPool, returning 0 if it's not there.
static Constant *LookupConstant(Value *V,
const SmallDenseMap<Value*, Constant*>& ConstantPool) {
if (Constant *C = dyn_cast<Constant>(V))
return C;
return ConstantPool.lookup(V);
}
/// Try to fold instruction I into a constant. This works for
/// simple instructions such as binary operations where both operands are
/// constant or can be replaced by constants from the ConstantPool. Returns the
/// resulting constant on success, 0 otherwise.
static Constant *
ConstantFold(Instruction *I, const DataLayout &DL,
const SmallDenseMap<Value *, Constant *> &ConstantPool) {
if (SelectInst *Select = dyn_cast<SelectInst>(I)) {
Constant *A = LookupConstant(Select->getCondition(), ConstantPool);
if (!A)
return nullptr;
if (A->isAllOnesValue())
return LookupConstant(Select->getTrueValue(), ConstantPool);
if (A->isNullValue())
return LookupConstant(Select->getFalseValue(), ConstantPool);
return nullptr;
}
SmallVector<Constant *, 4> COps;
for (unsigned N = 0, E = I->getNumOperands(); N != E; ++N) {
if (Constant *A = LookupConstant(I->getOperand(N), ConstantPool))
COps.push_back(A);
else
return nullptr;
}
if (CmpInst *Cmp = dyn_cast<CmpInst>(I)) {
return ConstantFoldCompareInstOperands(Cmp->getPredicate(), COps[0],
COps[1], DL);
}
return ConstantFoldInstOperands(I->getOpcode(), I->getType(), COps, DL);
}
/// Try to determine the resulting constant values in phi nodes
/// at the common destination basic block, *CommonDest, for one of the case
/// destionations CaseDest corresponding to value CaseVal (0 for the default
/// case), of a switch instruction SI.
static bool
GetCaseResults(SwitchInst *SI, ConstantInt *CaseVal, BasicBlock *CaseDest,
BasicBlock **CommonDest,
SmallVectorImpl<std::pair<PHINode *, Constant *>> &Res,
const DataLayout &DL) {
// The block from which we enter the common destination.
BasicBlock *Pred = SI->getParent();
// If CaseDest is empty except for some side-effect free instructions through
// which we can constant-propagate the CaseVal, continue to its successor.
SmallDenseMap<Value*, Constant*> ConstantPool;
ConstantPool.insert(std::make_pair(SI->getCondition(), CaseVal));
for (BasicBlock::iterator I = CaseDest->begin(), E = CaseDest->end(); I != E;
++I) {
if (TerminatorInst *T = dyn_cast<TerminatorInst>(I)) {
// If the terminator is a simple branch, continue to the next block.
if (T->getNumSuccessors() != 1)
return false;
Pred = CaseDest;
CaseDest = T->getSuccessor(0);
} else if (isa<DbgInfoIntrinsic>(I)) {
// Skip debug intrinsic.
continue;
} else if (Constant *C = ConstantFold(I, DL, ConstantPool)) {
// Instruction is side-effect free and constant.
// If the instruction has uses outside this block or a phi node slot for
// the block, it is not safe to bypass the instruction since it would then
// no longer dominate all its uses.
for (auto &Use : I->uses()) {
User *User = Use.getUser();
if (Instruction *I = dyn_cast<Instruction>(User))
if (I->getParent() == CaseDest)
continue;
if (PHINode *Phi = dyn_cast<PHINode>(User))
if (Phi->getIncomingBlock(Use) == CaseDest)
continue;
return false;
}
ConstantPool.insert(std::make_pair(I, C));
} else {
break;
}
}
// If we did not have a CommonDest before, use the current one.
if (!*CommonDest)
*CommonDest = CaseDest;
// If the destination isn't the common one, abort.
if (CaseDest != *CommonDest)
return false;
// Get the values for this case from phi nodes in the destination block.
BasicBlock::iterator I = (*CommonDest)->begin();
while (PHINode *PHI = dyn_cast<PHINode>(I++)) {
int Idx = PHI->getBasicBlockIndex(Pred);
if (Idx == -1)
continue;
Constant *ConstVal = LookupConstant(PHI->getIncomingValue(Idx),
ConstantPool);
if (!ConstVal)
return false;
// Be conservative about which kinds of constants we support.
if (!ValidLookupTableConstant(ConstVal))
return false;
Res.push_back(std::make_pair(PHI, ConstVal));
}
return Res.size() > 0;
}
// Helper function used to add CaseVal to the list of cases that generate
// Result.
static void MapCaseToResult(ConstantInt *CaseVal,
SwitchCaseResultVectorTy &UniqueResults,
Constant *Result) {
for (auto &I : UniqueResults) {
if (I.first == Result) {
I.second.push_back(CaseVal);
return;
}
}
UniqueResults.push_back(std::make_pair(Result,
SmallVector<ConstantInt*, 4>(1, CaseVal)));
}
// Helper function that initializes a map containing
// results for the PHI node of the common destination block for a switch
// instruction. Returns false if multiple PHI nodes have been found or if
// there is not a common destination block for the switch.
static bool InitializeUniqueCases(SwitchInst *SI, PHINode *&PHI,
BasicBlock *&CommonDest,
SwitchCaseResultVectorTy &UniqueResults,
Constant *&DefaultResult,
const DataLayout &DL) {
for (auto &I : SI->cases()) {
ConstantInt *CaseVal = I.getCaseValue();
// Resulting value at phi nodes for this case value.
SwitchCaseResultsTy Results;
if (!GetCaseResults(SI, CaseVal, I.getCaseSuccessor(), &CommonDest, Results,
DL))
return false;
// Only one value per case is permitted
if (Results.size() > 1)
return false;
MapCaseToResult(CaseVal, UniqueResults, Results.begin()->second);
// Check the PHI consistency.
if (!PHI)
PHI = Results[0].first;
else if (PHI != Results[0].first)
return false;
}
// Find the default result value.
SmallVector<std::pair<PHINode *, Constant *>, 1> DefaultResults;
BasicBlock *DefaultDest = SI->getDefaultDest();
GetCaseResults(SI, nullptr, SI->getDefaultDest(), &CommonDest, DefaultResults,
DL);
// If the default value is not found abort unless the default destination
// is unreachable.
DefaultResult =
DefaultResults.size() == 1 ? DefaultResults.begin()->second : nullptr;
if ((!DefaultResult &&
!isa<UnreachableInst>(DefaultDest->getFirstNonPHIOrDbg())))
return false;
return true;
}
// Helper function that checks if it is possible to transform a switch with only
// two cases (or two cases + default) that produces a result into a select.
// Example:
// switch (a) {
// case 10: %0 = icmp eq i32 %a, 10
// return 10; %1 = select i1 %0, i32 10, i32 4
// case 20: ----> %2 = icmp eq i32 %a, 20
// return 2; %3 = select i1 %2, i32 2, i32 %1
// default:
// return 4;
// }
static Value *
ConvertTwoCaseSwitch(const SwitchCaseResultVectorTy &ResultVector,
Constant *DefaultResult, Value *Condition,
IRBuilder<> &Builder) {
assert(ResultVector.size() == 2 &&
"We should have exactly two unique results at this point");
// If we are selecting between only two cases transform into a simple
// select or a two-way select if default is possible.
if (ResultVector[0].second.size() == 1 &&
ResultVector[1].second.size() == 1) {
ConstantInt *const FirstCase = ResultVector[0].second[0];
ConstantInt *const SecondCase = ResultVector[1].second[0];
bool DefaultCanTrigger = DefaultResult;
Value *SelectValue = ResultVector[1].first;
if (DefaultCanTrigger) {
Value *const ValueCompare =
Builder.CreateICmpEQ(Condition, SecondCase, "switch.selectcmp");
SelectValue = Builder.CreateSelect(ValueCompare, ResultVector[1].first,
DefaultResult, "switch.select");
}
Value *const ValueCompare =
Builder.CreateICmpEQ(Condition, FirstCase, "switch.selectcmp");
return Builder.CreateSelect(ValueCompare, ResultVector[0].first, SelectValue,
"switch.select");
}
return nullptr;
}
// Helper function to cleanup a switch instruction that has been converted into
// a select, fixing up PHI nodes and basic blocks.
static void RemoveSwitchAfterSelectConversion(SwitchInst *SI, PHINode *PHI,
Value *SelectValue,
IRBuilder<> &Builder) {
BasicBlock *SelectBB = SI->getParent();
while (PHI->getBasicBlockIndex(SelectBB) >= 0)
PHI->removeIncomingValue(SelectBB);
PHI->addIncoming(SelectValue, SelectBB);
Builder.CreateBr(PHI->getParent());
// Remove the switch.
for (unsigned i = 0, e = SI->getNumSuccessors(); i < e; ++i) {
BasicBlock *Succ = SI->getSuccessor(i);
if (Succ == PHI->getParent())
continue;
Succ->removePredecessor(SelectBB);
}
SI->eraseFromParent();
}
/// If the switch is only used to initialize one or more
/// phi nodes in a common successor block with only two different
/// constant values, replace the switch with select.
static bool SwitchToSelect(SwitchInst *SI, IRBuilder<> &Builder,
AssumptionCache *AC, const DataLayout &DL) {
Value *const Cond = SI->getCondition();
PHINode *PHI = nullptr;
BasicBlock *CommonDest = nullptr;
Constant *DefaultResult;
SwitchCaseResultVectorTy UniqueResults;
// Collect all the cases that will deliver the same value from the switch.
if (!InitializeUniqueCases(SI, PHI, CommonDest, UniqueResults, DefaultResult,
DL))
return false;
// Selects choose between maximum two values.
if (UniqueResults.size() != 2)
return false;
assert(PHI != nullptr && "PHI for value select not found");
Builder.SetInsertPoint(SI);
Value *SelectValue = ConvertTwoCaseSwitch(
UniqueResults,
DefaultResult, Cond, Builder);
if (SelectValue) {
RemoveSwitchAfterSelectConversion(SI, PHI, SelectValue, Builder);
return true;
}
// The switch couldn't be converted into a select.
return false;
}
namespace {
/// This class represents a lookup table that can be used to replace a switch.
class SwitchLookupTable {
public:
/// Create a lookup table to use as a switch replacement with the contents
/// of Values, using DefaultValue to fill any holes in the table.
SwitchLookupTable(
Module &M, uint64_t TableSize, ConstantInt *Offset,
const SmallVectorImpl<std::pair<ConstantInt *, Constant *>> &Values,
Constant *DefaultValue, const DataLayout &DL);
/// Build instructions with Builder to retrieve the value at
/// the position given by Index in the lookup table.
Value *BuildLookup(Value *Index, IRBuilder<> &Builder);
/// Return true if a table with TableSize elements of
/// type ElementType would fit in a target-legal register.
static bool WouldFitInRegister(const DataLayout &DL, uint64_t TableSize,
const Type *ElementType);
private:
// Depending on the contents of the table, it can be represented in
// different ways.
enum {
// For tables where each element contains the same value, we just have to
// store that single value and return it for each lookup.
SingleValueKind,
// For tables where there is a linear relationship between table index
// and values. We calculate the result with a simple multiplication
// and addition instead of a table lookup.
LinearMapKind,
// For small tables with integer elements, we can pack them into a bitmap
// that fits into a target-legal register. Values are retrieved by
// shift and mask operations.
BitMapKind,
// The table is stored as an array of values. Values are retrieved by load
// instructions from the table.
ArrayKind
} Kind;
// For SingleValueKind, this is the single value.
Constant *SingleValue;
// For BitMapKind, this is the bitmap.
ConstantInt *BitMap;
IntegerType *BitMapElementTy;
// For LinearMapKind, these are the constants used to derive the value.
ConstantInt *LinearOffset;
ConstantInt *LinearMultiplier;
// For ArrayKind, this is the array.
GlobalVariable *Array;
};
}
SwitchLookupTable::SwitchLookupTable(
Module &M, uint64_t TableSize, ConstantInt *Offset,
const SmallVectorImpl<std::pair<ConstantInt *, Constant *>> &Values,
Constant *DefaultValue, const DataLayout &DL)
: SingleValue(nullptr), BitMap(nullptr), BitMapElementTy(nullptr),
LinearOffset(nullptr), LinearMultiplier(nullptr), Array(nullptr) {
assert(Values.size() && "Can't build lookup table without values!");
assert(TableSize >= Values.size() && "Can't fit values in table!");
// If all values in the table are equal, this is that value.
SingleValue = Values.begin()->second;
Type *ValueType = Values.begin()->second->getType();
// Build up the table contents.
SmallVector<Constant*, 64> TableContents(TableSize);
for (size_t I = 0, E = Values.size(); I != E; ++I) {
ConstantInt *CaseVal = Values[I].first;
Constant *CaseRes = Values[I].second;
assert(CaseRes->getType() == ValueType);
uint64_t Idx = (CaseVal->getValue() - Offset->getValue())
.getLimitedValue();
TableContents[Idx] = CaseRes;
if (CaseRes != SingleValue)
SingleValue = nullptr;
}
// Fill in any holes in the table with the default result.
if (Values.size() < TableSize) {
assert(DefaultValue &&
"Need a default value to fill the lookup table holes.");
assert(DefaultValue->getType() == ValueType);
for (uint64_t I = 0; I < TableSize; ++I) {
if (!TableContents[I])
TableContents[I] = DefaultValue;
}
if (DefaultValue != SingleValue)
SingleValue = nullptr;
}
// If each element in the table contains the same value, we only need to store
// that single value.
if (SingleValue) {
Kind = SingleValueKind;
return;
}
// Check if we can derive the value with a linear transformation from the
// table index.
if (isa<IntegerType>(ValueType)) {
bool LinearMappingPossible = true;
APInt PrevVal;
APInt DistToPrev;
assert(TableSize >= 2 && "Should be a SingleValue table.");
// Check if there is the same distance between two consecutive values.
for (uint64_t I = 0; I < TableSize; ++I) {
ConstantInt *ConstVal = dyn_cast<ConstantInt>(TableContents[I]);
if (!ConstVal) {
// This is an undef. We could deal with it, but undefs in lookup tables
// are very seldom. It's probably not worth the additional complexity.
LinearMappingPossible = false;
break;
}
APInt Val = ConstVal->getValue();
if (I != 0) {
APInt Dist = Val - PrevVal;
if (I == 1) {
DistToPrev = Dist;
} else if (Dist != DistToPrev) {
LinearMappingPossible = false;
break;
}
}
PrevVal = Val;
}
if (LinearMappingPossible) {
LinearOffset = cast<ConstantInt>(TableContents[0]);
LinearMultiplier = ConstantInt::get(M.getContext(), DistToPrev);
Kind = LinearMapKind;
++NumLinearMaps;
return;
}
}
// If the type is integer and the table fits in a register, build a bitmap.
if (WouldFitInRegister(DL, TableSize, ValueType)) {
IntegerType *IT = cast<IntegerType>(ValueType);
APInt TableInt(TableSize * IT->getBitWidth(), 0);
for (uint64_t I = TableSize; I > 0; --I) {
TableInt <<= IT->getBitWidth();
// Insert values into the bitmap. Undef values are set to zero.
if (!isa<UndefValue>(TableContents[I - 1])) {
ConstantInt *Val = cast<ConstantInt>(TableContents[I - 1]);
TableInt |= Val->getValue().zext(TableInt.getBitWidth());
}
}
BitMap = ConstantInt::get(M.getContext(), TableInt);
BitMapElementTy = IT;
Kind = BitMapKind;
++NumBitMaps;
return;
}
// Store the table in an array.
ArrayType *ArrayTy = ArrayType::get(ValueType, TableSize);
Constant *Initializer = ConstantArray::get(ArrayTy, TableContents);
Array = new GlobalVariable(M, ArrayTy, /*constant=*/ true,
GlobalVariable::PrivateLinkage,
Initializer,
"switch.table");
Array->setUnnamedAddr(true);
Kind = ArrayKind;
}
Value *SwitchLookupTable::BuildLookup(Value *Index, IRBuilder<> &Builder) {
switch (Kind) {
case SingleValueKind:
return SingleValue;
case LinearMapKind: {
// Derive the result value from the input value.
Value *Result = Builder.CreateIntCast(Index, LinearMultiplier->getType(),
false, "switch.idx.cast");
if (!LinearMultiplier->isOne())
Result = Builder.CreateMul(Result, LinearMultiplier, "switch.idx.mult");
if (!LinearOffset->isZero())
Result = Builder.CreateAdd(Result, LinearOffset, "switch.offset");
return Result;
}
case BitMapKind: {
// Type of the bitmap (e.g. i59).
IntegerType *MapTy = BitMap->getType();
// Cast Index to the same type as the bitmap.
// Note: The Index is <= the number of elements in the table, so
// truncating it to the width of the bitmask is safe.
Value *ShiftAmt = Builder.CreateZExtOrTrunc(Index, MapTy, "switch.cast");
// Multiply the shift amount by the element width.
ShiftAmt = Builder.CreateMul(ShiftAmt,
ConstantInt::get(MapTy, BitMapElementTy->getBitWidth()),
"switch.shiftamt");
// Shift down.
Value *DownShifted = Builder.CreateLShr(BitMap, ShiftAmt,
"switch.downshift");
// Mask off.
return Builder.CreateTrunc(DownShifted, BitMapElementTy,
"switch.masked");
}
case ArrayKind: {
// Make sure the table index will not overflow when treated as signed.
IntegerType *IT = cast<IntegerType>(Index->getType());
uint64_t TableSize = Array->getInitializer()->getType()
->getArrayNumElements();
if (TableSize > (1ULL << (IT->getBitWidth() - 1)))
Index = Builder.CreateZExt(Index,
IntegerType::get(IT->getContext(),
IT->getBitWidth() + 1),
"switch.tableidx.zext");
Value *GEPIndices[] = { Builder.getInt32(0), Index };
Value *GEP = Builder.CreateInBoundsGEP(Array->getValueType(), Array,
GEPIndices, "switch.gep");
return Builder.CreateLoad(GEP, "switch.load");
}
}
llvm_unreachable("Unknown lookup table kind!");
}
bool SwitchLookupTable::WouldFitInRegister(const DataLayout &DL,
uint64_t TableSize,
const Type *ElementType) {
const IntegerType *IT = dyn_cast<IntegerType>(ElementType);
if (!IT)
return false;
// FIXME: If the type is wider than it needs to be, e.g. i8 but all values
// are <= 15, we could try to narrow the type.
// Avoid overflow, fitsInLegalInteger uses unsigned int for the width.
if (TableSize >= UINT_MAX/IT->getBitWidth())
return false;
return DL.fitsInLegalInteger(TableSize * IT->getBitWidth());
}
/// Determine whether a lookup table should be built for this switch, based on
/// the number of cases, size of the table, and the types of the results.
static bool
ShouldBuildLookupTable(SwitchInst *SI, uint64_t TableSize,
const TargetTransformInfo &TTI, const DataLayout &DL,
const SmallDenseMap<PHINode *, Type *> &ResultTypes) {
if (SI->getNumCases() > TableSize || TableSize >= UINT64_MAX / 10)
return false; // TableSize overflowed, or mul below might overflow.
bool AllTablesFitInRegister = true;
bool HasIllegalType = false;
for (const auto &I : ResultTypes) {
Type *Ty = I.second;
// Saturate this flag to true.
HasIllegalType = HasIllegalType || !TTI.isTypeLegal(Ty);
// Saturate this flag to false.
AllTablesFitInRegister = AllTablesFitInRegister &&
SwitchLookupTable::WouldFitInRegister(DL, TableSize, Ty);
// If both flags saturate, we're done. NOTE: This *only* works with
// saturating flags, and all flags have to saturate first due to the
// non-deterministic behavior of iterating over a dense map.
if (HasIllegalType && !AllTablesFitInRegister)
break;
}
// If each table would fit in a register, we should build it anyway.
if (AllTablesFitInRegister)
return true;
// Don't build a table that doesn't fit in-register if it has illegal types.
if (HasIllegalType)
return false;
// The table density should be at least 40%. This is the same criterion as for
// jump tables, see SelectionDAGBuilder::handleJTSwitchCase.
// FIXME: Find the best cut-off.
return SI->getNumCases() * 10 >= TableSize * 4;
}
/// Try to reuse the switch table index compare. Following pattern:
/// \code
/// if (idx < tablesize)
/// r = table[idx]; // table does not contain default_value
/// else
/// r = default_value;
/// if (r != default_value)
/// ...
/// \endcode
/// Is optimized to:
/// \code
/// cond = idx < tablesize;
/// if (cond)
/// r = table[idx];
/// else
/// r = default_value;
/// if (cond)
/// ...
/// \endcode
/// Jump threading will then eliminate the second if(cond).
static void reuseTableCompare(User *PhiUser, BasicBlock *PhiBlock,
BranchInst *RangeCheckBranch, Constant *DefaultValue,
const SmallVectorImpl<std::pair<ConstantInt*, Constant*> >& Values) {
ICmpInst *CmpInst = dyn_cast<ICmpInst>(PhiUser);
if (!CmpInst)
return;
// We require that the compare is in the same block as the phi so that jump
// threading can do its work afterwards.
if (CmpInst->getParent() != PhiBlock)
return;
Constant *CmpOp1 = dyn_cast<Constant>(CmpInst->getOperand(1));
if (!CmpOp1)
return;
Value *RangeCmp = RangeCheckBranch->getCondition();
Constant *TrueConst = ConstantInt::getTrue(RangeCmp->getType());
Constant *FalseConst = ConstantInt::getFalse(RangeCmp->getType());
// Check if the compare with the default value is constant true or false.
Constant *DefaultConst = ConstantExpr::getICmp(CmpInst->getPredicate(),
DefaultValue, CmpOp1, true);
if (DefaultConst != TrueConst && DefaultConst != FalseConst)
return;
// Check if the compare with the case values is distinct from the default
// compare result.
for (auto ValuePair : Values) {
Constant *CaseConst = ConstantExpr::getICmp(CmpInst->getPredicate(),
ValuePair.second, CmpOp1, true);
if (!CaseConst || CaseConst == DefaultConst)
return;
assert((CaseConst == TrueConst || CaseConst == FalseConst) &&
"Expect true or false as compare result.");
}
// Check if the branch instruction dominates the phi node. It's a simple
// dominance check, but sufficient for our needs.
// Although this check is invariant in the calling loops, it's better to do it
// at this late stage. Practically we do it at most once for a switch.
BasicBlock *BranchBlock = RangeCheckBranch->getParent();
for (auto PI = pred_begin(PhiBlock), E = pred_end(PhiBlock); PI != E; ++PI) {
BasicBlock *Pred = *PI;
if (Pred != BranchBlock && Pred->getUniquePredecessor() != BranchBlock)
return;
}
if (DefaultConst == FalseConst) {
// The compare yields the same result. We can replace it.
CmpInst->replaceAllUsesWith(RangeCmp);
++NumTableCmpReuses;
} else {
// The compare yields the same result, just inverted. We can replace it.
Value *InvertedTableCmp = BinaryOperator::CreateXor(RangeCmp,
ConstantInt::get(RangeCmp->getType(), 1), "inverted.cmp",
RangeCheckBranch);
CmpInst->replaceAllUsesWith(InvertedTableCmp);
++NumTableCmpReuses;
}
}
/// If the switch is only used to initialize one or more phi nodes in a common
/// successor block with different constant values, replace the switch with
/// lookup tables.
static bool SwitchToLookupTable(SwitchInst *SI, IRBuilder<> &Builder,
const DataLayout &DL,
const TargetTransformInfo &TTI) {
assert(SI->getNumCases() > 1 && "Degenerate switch?");
// Only build lookup table when we have a target that supports it.
if (!TTI.shouldBuildLookupTables())
return false;
// FIXME: If the switch is too sparse for a lookup table, perhaps we could
// split off a dense part and build a lookup table for that.
// FIXME: This creates arrays of GEPs to constant strings, which means each
// GEP needs a runtime relocation in PIC code. We should just build one big
// string and lookup indices into that.
// Ignore switches with less than three cases. Lookup tables will not make them
// faster, so we don't analyze them.
if (SI->getNumCases() < 3)
return false;
// Figure out the corresponding result for each case value and phi node in the
// common destination, as well as the min and max case values.
assert(SI->case_begin() != SI->case_end());
SwitchInst::CaseIt CI = SI->case_begin();
ConstantInt *MinCaseVal = CI.getCaseValue();
ConstantInt *MaxCaseVal = CI.getCaseValue();
BasicBlock *CommonDest = nullptr;
typedef SmallVector<std::pair<ConstantInt*, Constant*>, 4> ResultListTy;
SmallDenseMap<PHINode*, ResultListTy> ResultLists;
SmallDenseMap<PHINode*, Constant*> DefaultResults;
SmallDenseMap<PHINode*, Type*> ResultTypes;
SmallVector<PHINode*, 4> PHIs;
for (SwitchInst::CaseIt E = SI->case_end(); CI != E; ++CI) {
ConstantInt *CaseVal = CI.getCaseValue();
if (CaseVal->getValue().slt(MinCaseVal->getValue()))
MinCaseVal = CaseVal;
if (CaseVal->getValue().sgt(MaxCaseVal->getValue()))
MaxCaseVal = CaseVal;
// Resulting value at phi nodes for this case value.
typedef SmallVector<std::pair<PHINode*, Constant*>, 4> ResultsTy;
ResultsTy Results;
if (!GetCaseResults(SI, CaseVal, CI.getCaseSuccessor(), &CommonDest,
Results, DL))
return false;
// Append the result from this case to the list for each phi.
for (const auto &I : Results) {
PHINode *PHI = I.first;
Constant *Value = I.second;
if (!ResultLists.count(PHI))
PHIs.push_back(PHI);
ResultLists[PHI].push_back(std::make_pair(CaseVal, Value));
}
}
// Keep track of the result types.
for (PHINode *PHI : PHIs) {
ResultTypes[PHI] = ResultLists[PHI][0].second->getType();
}
uint64_t NumResults = ResultLists[PHIs[0]].size();
APInt RangeSpread = MaxCaseVal->getValue() - MinCaseVal->getValue();
uint64_t TableSize = RangeSpread.getLimitedValue() + 1;
bool TableHasHoles = (NumResults < TableSize);
// If the table has holes, we need a constant result for the default case
// or a bitmask that fits in a register.
SmallVector<std::pair<PHINode*, Constant*>, 4> DefaultResultsList;
bool HasDefaultResults = GetCaseResults(SI, nullptr, SI->getDefaultDest(),
&CommonDest, DefaultResultsList, DL);
bool NeedMask = (TableHasHoles && !HasDefaultResults);
if (NeedMask) {
// As an extra penalty for the validity test we require more cases.
if (SI->getNumCases() < 4) // FIXME: Find best threshold value (benchmark).
return false;
if (!DL.fitsInLegalInteger(TableSize))
return false;
}
for (const auto &I : DefaultResultsList) {
PHINode *PHI = I.first;
Constant *Result = I.second;
DefaultResults[PHI] = Result;
}
if (!ShouldBuildLookupTable(SI, TableSize, TTI, DL, ResultTypes))
return false;
// Create the BB that does the lookups.
Module &Mod = *CommonDest->getParent()->getParent();
BasicBlock *LookupBB = BasicBlock::Create(Mod.getContext(),
"switch.lookup",
CommonDest->getParent(),
CommonDest);
// Compute the table index value.
Builder.SetInsertPoint(SI);
Value *TableIndex = Builder.CreateSub(SI->getCondition(), MinCaseVal,
"switch.tableidx");
// Compute the maximum table size representable by the integer type we are
// switching upon.
unsigned CaseSize = MinCaseVal->getType()->getPrimitiveSizeInBits();
uint64_t MaxTableSize = CaseSize > 63 ? UINT64_MAX : 1ULL << CaseSize;
assert(MaxTableSize >= TableSize &&
"It is impossible for a switch to have more entries than the max "
"representable value of its input integer type's size.");
// If the default destination is unreachable, or if the lookup table covers
// all values of the conditional variable, branch directly to the lookup table
// BB. Otherwise, check that the condition is within the case range.
const bool DefaultIsReachable =
!isa<UnreachableInst>(SI->getDefaultDest()->getFirstNonPHIOrDbg());
const bool GeneratingCoveredLookupTable = (MaxTableSize == TableSize);
BranchInst *RangeCheckBranch = nullptr;
if (!DefaultIsReachable || GeneratingCoveredLookupTable) {
Builder.CreateBr(LookupBB);
// Note: We call removeProdecessor later since we need to be able to get the
// PHI value for the default case in case we're using a bit mask.
} else {
Value *Cmp = Builder.CreateICmpULT(TableIndex, ConstantInt::get(
MinCaseVal->getType(), TableSize));
RangeCheckBranch = Builder.CreateCondBr(Cmp, LookupBB, SI->getDefaultDest());
}
// Populate the BB that does the lookups.
Builder.SetInsertPoint(LookupBB);
if (NeedMask) {
// Before doing the lookup we do the hole check.
// The LookupBB is therefore re-purposed to do the hole check
// and we create a new LookupBB.
BasicBlock *MaskBB = LookupBB;
MaskBB->setName("switch.hole_check");
LookupBB = BasicBlock::Create(Mod.getContext(),
"switch.lookup",
CommonDest->getParent(),
CommonDest);
// Make the mask's bitwidth at least 8bit and a power-of-2 to avoid
// unnecessary illegal types.
uint64_t TableSizePowOf2 = NextPowerOf2(std::max(7ULL, TableSize - 1ULL));
APInt MaskInt(TableSizePowOf2, 0);
APInt One(TableSizePowOf2, 1);
// Build bitmask; fill in a 1 bit for every case.
const ResultListTy &ResultList = ResultLists[PHIs[0]];
for (size_t I = 0, E = ResultList.size(); I != E; ++I) {
uint64_t Idx = (ResultList[I].first->getValue() -
MinCaseVal->getValue()).getLimitedValue();
MaskInt |= One << Idx;
}
ConstantInt *TableMask = ConstantInt::get(Mod.getContext(), MaskInt);
// Get the TableIndex'th bit of the bitmask.
// If this bit is 0 (meaning hole) jump to the default destination,
// else continue with table lookup.
IntegerType *MapTy = TableMask->getType();
Value *MaskIndex = Builder.CreateZExtOrTrunc(TableIndex, MapTy,
"switch.maskindex");
Value *Shifted = Builder.CreateLShr(TableMask, MaskIndex,
"switch.shifted");
Value *LoBit = Builder.CreateTrunc(Shifted,
Type::getInt1Ty(Mod.getContext()),
"switch.lobit");
Builder.CreateCondBr(LoBit, LookupBB, SI->getDefaultDest());
Builder.SetInsertPoint(LookupBB);
AddPredecessorToBlock(SI->getDefaultDest(), MaskBB, SI->getParent());
}
if (!DefaultIsReachable || GeneratingCoveredLookupTable) {
// We cached PHINodes in PHIs, to avoid accessing deleted PHINodes later,
// do not delete PHINodes here.
SI->getDefaultDest()->removePredecessor(SI->getParent(),
/*DontDeleteUselessPHIs=*/true);
}
bool ReturnedEarly = false;
for (size_t I = 0, E = PHIs.size(); I != E; ++I) {
PHINode *PHI = PHIs[I];
const ResultListTy &ResultList = ResultLists[PHI];
// If using a bitmask, use any value to fill the lookup table holes.
Constant *DV = NeedMask ? ResultLists[PHI][0].second : DefaultResults[PHI];
SwitchLookupTable Table(Mod, TableSize, MinCaseVal, ResultList, DV, DL);
Value *Result = Table.BuildLookup(TableIndex, Builder);
// If the result is used to return immediately from the function, we want to
// do that right here.
if (PHI->hasOneUse() && isa<ReturnInst>(*PHI->user_begin()) &&
PHI->user_back() == CommonDest->getFirstNonPHIOrDbg()) {
Builder.CreateRet(Result);
ReturnedEarly = true;
break;
}
// Do a small peephole optimization: re-use the switch table compare if
// possible.
if (!TableHasHoles && HasDefaultResults && RangeCheckBranch) {
BasicBlock *PhiBlock = PHI->getParent();
// Search for compare instructions which use the phi.
for (auto *User : PHI->users()) {
reuseTableCompare(User, PhiBlock, RangeCheckBranch, DV, ResultList);
}
}
PHI->addIncoming(Result, LookupBB);
}
if (!ReturnedEarly)
Builder.CreateBr(CommonDest);
// Remove the switch.
for (unsigned i = 0, e = SI->getNumSuccessors(); i < e; ++i) {
BasicBlock *Succ = SI->getSuccessor(i);
if (Succ == SI->getDefaultDest())
continue;
Succ->removePredecessor(SI->getParent());
}
SI->eraseFromParent();
++NumLookupTables;
if (NeedMask)
++NumLookupTablesHoles;
return true;
}
bool SimplifyCFGOpt::SimplifySwitch(SwitchInst *SI, IRBuilder<> &Builder) {
BasicBlock *BB = SI->getParent();
if (isValueEqualityComparison(SI)) {
// If we only have one predecessor, and if it is a branch on this value,
// see if that predecessor totally determines the outcome of this switch.
if (BasicBlock *OnlyPred = BB->getSinglePredecessor())
if (SimplifyEqualityComparisonWithOnlyPredecessor(SI, OnlyPred, Builder))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
Value *Cond = SI->getCondition();
if (SelectInst *Select = dyn_cast<SelectInst>(Cond))
if (SimplifySwitchOnSelect(SI, Select))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
// If the block only contains the switch, see if we can fold the block
// away into any preds.
BasicBlock::iterator BBI = BB->begin();
// Ignore dbg intrinsics.
while (isa<DbgInfoIntrinsic>(BBI))
++BBI;
if (SI == &*BBI)
if (FoldValueComparisonIntoPredecessors(SI, Builder))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
}
// Try to transform the switch into an icmp and a branch.
if (TurnSwitchRangeIntoICmp(SI, Builder))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
// Remove unreachable cases.
if (EliminateDeadSwitchCases(SI, AC, DL))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
if (SwitchToSelect(SI, Builder, AC, DL))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
if (ForwardSwitchConditionToPHI(SI))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
if (SwitchToLookupTable(SI, Builder, DL, TTI))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
return false;
}
bool SimplifyCFGOpt::SimplifyIndirectBr(IndirectBrInst *IBI) {
BasicBlock *BB = IBI->getParent();
bool Changed = false;
// Eliminate redundant destinations.
SmallPtrSet<Value *, 8> Succs;
for (unsigned i = 0, e = IBI->getNumDestinations(); i != e; ++i) {
BasicBlock *Dest = IBI->getDestination(i);
if (!Dest->hasAddressTaken() || !Succs.insert(Dest).second) {
Dest->removePredecessor(BB);
IBI->removeDestination(i);
--i; --e;
Changed = true;
}
}
if (IBI->getNumDestinations() == 0) {
// If the indirectbr has no successors, change it to unreachable.
new UnreachableInst(IBI->getContext(), IBI);
EraseTerminatorInstAndDCECond(IBI);
return true;
}
if (IBI->getNumDestinations() == 1) {
// If the indirectbr has one successor, change it to a direct branch.
BranchInst::Create(IBI->getDestination(0), IBI);
EraseTerminatorInstAndDCECond(IBI);
return true;
}
if (SelectInst *SI = dyn_cast<SelectInst>(IBI->getAddress())) {
if (SimplifyIndirectBrOnSelect(IBI, SI))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
}
return Changed;
}
/// Given an block with only a single landing pad and a unconditional branch
/// try to find another basic block which this one can be merged with. This
/// handles cases where we have multiple invokes with unique landing pads, but
/// a shared handler.
///
/// We specifically choose to not worry about merging non-empty blocks
/// here. That is a PRE/scheduling problem and is best solved elsewhere. In
/// practice, the optimizer produces empty landing pad blocks quite frequently
/// when dealing with exception dense code. (see: instcombine, gvn, if-else
/// sinking in this file)
///
/// This is primarily a code size optimization. We need to avoid performing
/// any transform which might inhibit optimization (such as our ability to
/// specialize a particular handler via tail commoning). We do this by not
/// merging any blocks which require us to introduce a phi. Since the same
/// values are flowing through both blocks, we don't loose any ability to
/// specialize. If anything, we make such specialization more likely.
///
/// TODO - This transformation could remove entries from a phi in the target
/// block when the inputs in the phi are the same for the two blocks being
/// merged. In some cases, this could result in removal of the PHI entirely.
static bool TryToMergeLandingPad(LandingPadInst *LPad, BranchInst *BI,
BasicBlock *BB) {
auto Succ = BB->getUniqueSuccessor();
assert(Succ);
// If there's a phi in the successor block, we'd likely have to introduce
// a phi into the merged landing pad block.
if (isa<PHINode>(*Succ->begin()))
return false;
for (BasicBlock *OtherPred : predecessors(Succ)) {
if (BB == OtherPred)
continue;
BasicBlock::iterator I = OtherPred->begin();
LandingPadInst *LPad2 = dyn_cast<LandingPadInst>(I);
if (!LPad2 || !LPad2->isIdenticalTo(LPad))
continue;
for (++I; isa<DbgInfoIntrinsic>(I); ++I) {}
BranchInst *BI2 = dyn_cast<BranchInst>(I);
if (!BI2 || !BI2->isIdenticalTo(BI))
continue;
// We've found an identical block. Update our predeccessors to take that
// path instead and make ourselves dead.
SmallSet<BasicBlock *, 16> Preds;
Preds.insert(pred_begin(BB), pred_end(BB));
for (BasicBlock *Pred : Preds) {
InvokeInst *II = cast<InvokeInst>(Pred->getTerminator());
assert(II->getNormalDest() != BB &&
II->getUnwindDest() == BB && "unexpected successor");
II->setUnwindDest(OtherPred);
}
// The debug info in OtherPred doesn't cover the merged control flow that
// used to go through BB. We need to delete it or update it.
for (auto I = OtherPred->begin(), E = OtherPred->end();
I != E;) {
Instruction &Inst = *I; I++;
if (isa<DbgInfoIntrinsic>(Inst))
Inst.eraseFromParent();
}
SmallSet<BasicBlock *, 16> Succs;
Succs.insert(succ_begin(BB), succ_end(BB));
for (BasicBlock *Succ : Succs) {
Succ->removePredecessor(BB);
}
IRBuilder<> Builder(BI);
Builder.CreateUnreachable();
BI->eraseFromParent();
return true;
}
return false;
}
bool SimplifyCFGOpt::SimplifyUncondBranch(BranchInst *BI, IRBuilder<> &Builder){
BasicBlock *BB = BI->getParent();
if (SinkCommon && SinkThenElseCodeToEnd(BI))
return true;
// If the Terminator is the only non-phi instruction, simplify the block.
BasicBlock::iterator I = BB->getFirstNonPHIOrDbg();
if (I->isTerminator() && BB != &BB->getParent()->getEntryBlock() &&
TryToSimplifyUncondBranchFromEmptyBlock(BB))
return true;
// If the only instruction in the block is a seteq/setne comparison
// against a constant, try to simplify the block.
if (ICmpInst *ICI = dyn_cast<ICmpInst>(I))
if (ICI->isEquality() && isa<ConstantInt>(ICI->getOperand(1))) {
for (++I; isa<DbgInfoIntrinsic>(I); ++I)
;
if (I->isTerminator() &&
TryToSimplifyUncondBranchWithICmpInIt(ICI, Builder, DL, TTI,
BonusInstThreshold, AC))
return true;
}
// See if we can merge an empty landing pad block with another which is
// equivalent.
if (LandingPadInst *LPad = dyn_cast<LandingPadInst>(I)) {
for (++I; isa<DbgInfoIntrinsic>(I); ++I) {}
if (I->isTerminator() &&
TryToMergeLandingPad(LPad, BI, BB))
return true;
}
// If this basic block is ONLY a compare and a branch, and if a predecessor
// branches to us and our successor, fold the comparison into the
// predecessor and use logical operations to update the incoming value
// for PHI nodes in common successor.
if (FoldBranchToCommonDest(BI, BonusInstThreshold))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
return false;
}
bool SimplifyCFGOpt::SimplifyCondBranch(BranchInst *BI, IRBuilder<> &Builder) {
BasicBlock *BB = BI->getParent();
// Conditional branch
if (isValueEqualityComparison(BI)) {
// If we only have one predecessor, and if it is a branch on this value,
// see if that predecessor totally determines the outcome of this
// switch.
if (BasicBlock *OnlyPred = BB->getSinglePredecessor())
if (SimplifyEqualityComparisonWithOnlyPredecessor(BI, OnlyPred, Builder))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
// This block must be empty, except for the setcond inst, if it exists.
// Ignore dbg intrinsics.
BasicBlock::iterator I = BB->begin();
// Ignore dbg intrinsics.
while (isa<DbgInfoIntrinsic>(I))
++I;
if (&*I == BI) {
if (FoldValueComparisonIntoPredecessors(BI, Builder))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
} else if (&*I == cast<Instruction>(BI->getCondition())){
++I;
// Ignore dbg intrinsics.
while (isa<DbgInfoIntrinsic>(I))
++I;
if (&*I == BI && FoldValueComparisonIntoPredecessors(BI, Builder))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
}
}
#if 0 // HLSL Change Begins. This will not help for hlsl.
// Try to turn "br (X == 0 | X == 1), T, F" into a switch instruction.
if (SimplifyBranchOnICmpChain(BI, Builder, DL))
return true;
#endif // HLSL Change Ends.
// If this basic block is ONLY a compare and a branch, and if a predecessor
// branches to us and one of our successors, fold the comparison into the
// predecessor and use logical operations to pick the right destination.
if (FoldBranchToCommonDest(BI, BonusInstThreshold))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
// We have a conditional branch to two blocks that are only reachable
// from BI. We know that the condbr dominates the two blocks, so see if
// there is any identical code in the "then" and "else" blocks. If so, we
// can hoist it up to the branching block.
if (BI->getSuccessor(0)->getSinglePredecessor()) {
if (BI->getSuccessor(1)->getSinglePredecessor()) {
if (HoistThenElseCodeToIf(BI, TTI))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
} else {
// If Successor #1 has multiple preds, we may be able to conditionally
// execute Successor #0 if it branches to Successor #1.
TerminatorInst *Succ0TI = BI->getSuccessor(0)->getTerminator();
if (Succ0TI->getNumSuccessors() == 1 &&
Succ0TI->getSuccessor(0) == BI->getSuccessor(1))
if (SpeculativelyExecuteBB(BI, BI->getSuccessor(0), TTI))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
}
} else if (BI->getSuccessor(1)->getSinglePredecessor()) {
// If Successor #0 has multiple preds, we may be able to conditionally
// execute Successor #1 if it branches to Successor #0.
TerminatorInst *Succ1TI = BI->getSuccessor(1)->getTerminator();
if (Succ1TI->getNumSuccessors() == 1 &&
Succ1TI->getSuccessor(0) == BI->getSuccessor(0))
if (SpeculativelyExecuteBB(BI, BI->getSuccessor(1), TTI))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
}
#if 0 // HLSL Change - this transformation creates unstructured flow
// If this is a branch on a phi node in the current block, thread control
// through this block if any PHI node entries are constants.
if (PHINode *PN = dyn_cast<PHINode>(BI->getCondition()))
if (PN->getParent() == BI->getParent())
if (FoldCondBranchOnPHI(BI, DL))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
#endif // HLSL Change
// Scan predecessor blocks for conditional branches.
for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI)
if (BranchInst *PBI = dyn_cast<BranchInst>((*PI)->getTerminator()))
if (PBI != BI && PBI->isConditional())
if (SimplifyCondBranchToCondBranch(PBI, BI))
return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true;
return false;
}
/// Check if passing a value to an instruction will cause undefined behavior.
static bool passingValueIsAlwaysUndefined(Value *V, Instruction *I) {
Constant *C = dyn_cast<Constant>(V);
if (!C)
return false;
if (I->use_empty())
return false;
if (C->isNullValue()) {
// Only look at the first use, avoid hurting compile time with long uselists
User *Use = *I->user_begin();
// Now make sure that there are no instructions in between that can alter
// control flow (eg. calls)
for (BasicBlock::iterator i = ++BasicBlock::iterator(I); &*i != Use; ++i)
if (i == I->getParent()->end() || i->mayHaveSideEffects())
return false;
// Look through GEPs. A load from a GEP derived from NULL is still undefined
if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Use))
if (GEP->getPointerOperand() == I)
return passingValueIsAlwaysUndefined(V, GEP);
// Look through bitcasts.
if (BitCastInst *BC = dyn_cast<BitCastInst>(Use))
return passingValueIsAlwaysUndefined(V, BC);
// Load from null is undefined.
if (LoadInst *LI = dyn_cast<LoadInst>(Use))
if (!LI->isVolatile())
return LI->getPointerAddressSpace() == 0;
// Store to null is undefined.
if (StoreInst *SI = dyn_cast<StoreInst>(Use))
if (!SI->isVolatile())
return SI->getPointerAddressSpace() == 0 && SI->getPointerOperand() == I;
}
return false;
}
/// If BB has an incoming value that will always trigger undefined behavior
/// (eg. null pointer dereference), remove the branch leading here.
static bool removeUndefIntroducingPredecessor(BasicBlock *BB) {
for (BasicBlock::iterator i = BB->begin();
PHINode *PHI = dyn_cast<PHINode>(i); ++i)
for (unsigned i = 0, e = PHI->getNumIncomingValues(); i != e; ++i)
if (passingValueIsAlwaysUndefined(PHI->getIncomingValue(i), PHI)) {
TerminatorInst *T = PHI->getIncomingBlock(i)->getTerminator();
IRBuilder<> Builder(T);
if (BranchInst *BI = dyn_cast<BranchInst>(T)) {
BB->removePredecessor(PHI->getIncomingBlock(i));
// Turn uncoditional branches into unreachables and remove the dead
// destination from conditional branches.
if (BI->isUnconditional())
Builder.CreateUnreachable();
else
Builder.CreateBr(BI->getSuccessor(0) == BB ? BI->getSuccessor(1) :
BI->getSuccessor(0));
BI->eraseFromParent();
return true;
}
// TODO: SwitchInst.
}
return false;
}
bool SimplifyCFGOpt::run(BasicBlock *BB) {
bool Changed = false;
assert(BB && BB->getParent() && "Block not embedded in function!");
assert(BB->getTerminator() && "Degenerate basic block encountered!");
// Remove basic blocks that have no predecessors (except the entry block)...
// or that just have themself as a predecessor. These are unreachable.
if ((pred_empty(BB) &&
BB != &BB->getParent()->getEntryBlock()) ||
BB->getSinglePredecessor() == BB) {
DEBUG(dbgs() << "Removing BB: \n" << *BB);
DeleteDeadBlock(BB);
return true;
}
// Check to see if we can constant propagate this terminator instruction
// away...
Changed |= ConstantFoldTerminator(BB, true);
// Check for and eliminate duplicate PHI nodes in this block.
Changed |= EliminateDuplicatePHINodes(BB);
// Check for and remove branches that will always cause undefined behavior.
Changed |= removeUndefIntroducingPredecessor(BB);
// Merge basic blocks into their predecessor if there is only one distinct
// pred, and if there is only one distinct successor of the predecessor, and
// if there are no PHI nodes.
//
if (MergeBlockIntoPredecessor(BB))
return true;
IRBuilder<> Builder(BB);
// If there is a trivial two-entry PHI node in this basic block, and we can
// eliminate it, do so now.
if (PHINode *PN = dyn_cast<PHINode>(BB->begin()))
if (PN->getNumIncomingValues() == 2)
Changed |= FoldTwoEntryPHINode(PN, TTI, DL);
Builder.SetInsertPoint(BB->getTerminator());
if (BranchInst *BI = dyn_cast<BranchInst>(BB->getTerminator())) {
if (BI->isUnconditional()) {
if (SimplifyUncondBranch(BI, Builder)) return true;
} else {
if (SimplifyCondBranch(BI, Builder)) return true;
}
} else if (ReturnInst *RI = dyn_cast<ReturnInst>(BB->getTerminator())) {
if (SimplifyReturn(RI, Builder)) return true;
} else if (ResumeInst *RI = dyn_cast<ResumeInst>(BB->getTerminator())) {
if (SimplifyResume(RI, Builder)) return true;
} else if (SwitchInst *SI = dyn_cast<SwitchInst>(BB->getTerminator())) {
if (SimplifySwitch(SI, Builder)) return true;
} else if (UnreachableInst *UI =
dyn_cast<UnreachableInst>(BB->getTerminator())) {
if (SimplifyUnreachable(UI)) return true;
} else if (IndirectBrInst *IBI =
dyn_cast<IndirectBrInst>(BB->getTerminator())) {
if (SimplifyIndirectBr(IBI)) return true;
}
return Changed;
}
/// This function is used to do simplification of a CFG.
/// For example, it adjusts branches to branches to eliminate the extra hop,
/// eliminates unreachable basic blocks, and does other "peephole" optimization
/// of the CFG. It returns true if a modification was made.
///
bool llvm::SimplifyCFG(BasicBlock *BB, const TargetTransformInfo &TTI,
unsigned BonusInstThreshold, AssumptionCache *AC) {
return SimplifyCFGOpt(TTI, BB->getModule()->getDataLayout(),
BonusInstThreshold, AC).run(BB);
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/LoopSimplify.cpp | //===- LoopSimplify.cpp - Loop Canonicalization Pass ----------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This pass performs several transformations to transform natural loops into a
// simpler form, which makes subsequent analyses and transformations simpler and
// more effective.
//
// Loop pre-header insertion guarantees that there is a single, non-critical
// entry edge from outside of the loop to the loop header. This simplifies a
// number of analyses and transformations, such as LICM.
//
// Loop exit-block insertion guarantees that all exit blocks from the loop
// (blocks which are outside of the loop that have predecessors inside of the
// loop) only have predecessors from inside of the loop (and are thus dominated
// by the loop header). This simplifies transformations such as store-sinking
// that are built into LICM.
//
// This pass also guarantees that loops will have exactly one backedge.
//
// Indirectbr instructions introduce several complications. If the loop
// contains or is entered by an indirectbr instruction, it may not be possible
// to transform the loop and make these guarantees. Client code should check
// that these conditions are true before relying on them.
//
// Note that the simplifycfg pass will clean up blocks which are split out but
// end up being unnecessary, so usage of this pass should not pessimize
// generated code.
//
// This pass obviously modifies the CFG, but updates loop information and
// dominator information.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Scalar.h"
#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/SetOperations.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/DependenceAnalysis.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Type.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/LoopUtils.h"
#include "llvm/Transforms/Utils/LoopSimplify.h"
using namespace llvm;
#define DEBUG_TYPE "loop-simplify"
STATISTIC(NumInserted, "Number of pre-header or exit blocks inserted");
STATISTIC(NumNested , "Number of nested loops split out");
// If the block isn't already, move the new block to right after some 'outside
// block' block. This prevents the preheader from being placed inside the loop
// body, e.g. when the loop hasn't been rotated.
static void placeSplitBlockCarefully(BasicBlock *NewBB,
SmallVectorImpl<BasicBlock *> &SplitPreds,
Loop *L) {
// Check to see if NewBB is already well placed.
Function::iterator BBI = NewBB; --BBI;
for (unsigned i = 0, e = SplitPreds.size(); i != e; ++i) {
if (&*BBI == SplitPreds[i])
return;
}
// If it isn't already after an outside block, move it after one. This is
// always good as it makes the uncond branch from the outside block into a
// fall-through.
// Figure out *which* outside block to put this after. Prefer an outside
// block that neighbors a BB actually in the loop.
BasicBlock *FoundBB = nullptr;
for (unsigned i = 0, e = SplitPreds.size(); i != e; ++i) {
Function::iterator BBI = SplitPreds[i];
if (++BBI != NewBB->getParent()->end() &&
L->contains(BBI)) {
FoundBB = SplitPreds[i];
break;
}
}
// If our heuristic for a *good* bb to place this after doesn't find
// anything, just pick something. It's likely better than leaving it within
// the loop.
if (!FoundBB)
FoundBB = SplitPreds[0];
NewBB->moveAfter(FoundBB);
}
/// InsertPreheaderForLoop - Once we discover that a loop doesn't have a
/// preheader, this method is called to insert one. This method has two phases:
/// preheader insertion and analysis updating.
///
BasicBlock *llvm::InsertPreheaderForLoop(Loop *L, Pass *PP) {
BasicBlock *Header = L->getHeader();
// Get analyses that we try to update.
auto *AA = PP->getAnalysisIfAvailable<AliasAnalysis>();
auto *DTWP = PP->getAnalysisIfAvailable<DominatorTreeWrapperPass>();
auto *DT = DTWP ? &DTWP->getDomTree() : nullptr;
auto *LIWP = PP->getAnalysisIfAvailable<LoopInfoWrapperPass>();
auto *LI = LIWP ? &LIWP->getLoopInfo() : nullptr;
bool PreserveLCSSA = PP->mustPreserveAnalysisID(LCSSAID);
// Compute the set of predecessors of the loop that are not in the loop.
SmallVector<BasicBlock*, 8> OutsideBlocks;
for (pred_iterator PI = pred_begin(Header), PE = pred_end(Header);
PI != PE; ++PI) {
BasicBlock *P = *PI;
if (!L->contains(P)) { // Coming in from outside the loop?
// If the loop is branched to from an indirect branch, we won't
// be able to fully transform the loop, because it prohibits
// edge splitting.
if (isa<IndirectBrInst>(P->getTerminator())) return nullptr;
// Keep track of it.
OutsideBlocks.push_back(P);
}
}
// Split out the loop pre-header.
BasicBlock *PreheaderBB;
PreheaderBB = SplitBlockPredecessors(Header, OutsideBlocks, ".preheader",
AA, DT, LI, PreserveLCSSA);
DEBUG(dbgs() << "LoopSimplify: Creating pre-header "
<< PreheaderBB->getName() << "\n");
// Make sure that NewBB is put someplace intelligent, which doesn't mess up
// code layout too horribly.
placeSplitBlockCarefully(PreheaderBB, OutsideBlocks, L);
return PreheaderBB;
}
/// \brief Ensure that the loop preheader dominates all exit blocks.
///
/// This method is used to split exit blocks that have predecessors outside of
/// the loop.
static BasicBlock *rewriteLoopExitBlock(Loop *L, BasicBlock *Exit,
AliasAnalysis *AA, DominatorTree *DT,
LoopInfo *LI, Pass *PP) {
SmallVector<BasicBlock*, 8> LoopBlocks;
for (pred_iterator I = pred_begin(Exit), E = pred_end(Exit); I != E; ++I) {
BasicBlock *P = *I;
if (L->contains(P)) {
// Don't do this if the loop is exited via an indirect branch.
if (isa<IndirectBrInst>(P->getTerminator())) return nullptr;
LoopBlocks.push_back(P);
}
}
assert(!LoopBlocks.empty() && "No edges coming in from outside the loop?");
BasicBlock *NewExitBB = nullptr;
bool PreserveLCSSA = PP->mustPreserveAnalysisID(LCSSAID);
NewExitBB = SplitBlockPredecessors(Exit, LoopBlocks, ".loopexit", AA, DT,
LI, PreserveLCSSA);
DEBUG(dbgs() << "LoopSimplify: Creating dedicated exit block "
<< NewExitBB->getName() << "\n");
return NewExitBB;
}
/// Add the specified block, and all of its predecessors, to the specified set,
/// if it's not already in there. Stop predecessor traversal when we reach
/// StopBlock.
static void addBlockAndPredsToSet(BasicBlock *InputBB, BasicBlock *StopBlock,
std::set<BasicBlock*> &Blocks) {
SmallVector<BasicBlock *, 8> Worklist;
Worklist.push_back(InputBB);
do {
BasicBlock *BB = Worklist.pop_back_val();
if (Blocks.insert(BB).second && BB != StopBlock)
// If BB is not already processed and it is not a stop block then
// insert its predecessor in the work list
for (pred_iterator I = pred_begin(BB), E = pred_end(BB); I != E; ++I) {
BasicBlock *WBB = *I;
Worklist.push_back(WBB);
}
} while (!Worklist.empty());
}
/// \brief The first part of loop-nestification is to find a PHI node that tells
/// us how to partition the loops.
static PHINode *findPHIToPartitionLoops(Loop *L, AliasAnalysis *AA,
DominatorTree *DT,
AssumptionCache *AC) {
const DataLayout &DL = L->getHeader()->getModule()->getDataLayout();
for (BasicBlock::iterator I = L->getHeader()->begin(); isa<PHINode>(I); ) {
PHINode *PN = cast<PHINode>(I);
++I;
if (Value *V = SimplifyInstruction(PN, DL, nullptr, DT, AC)) {
// This is a degenerate PHI already, don't modify it!
PN->replaceAllUsesWith(V);
if (AA) AA->deleteValue(PN);
PN->eraseFromParent();
continue;
}
// Scan this PHI node looking for a use of the PHI node by itself.
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
if (PN->getIncomingValue(i) == PN &&
L->contains(PN->getIncomingBlock(i)))
// We found something tasty to remove.
return PN;
}
return nullptr;
}
/// \brief If this loop has multiple backedges, try to pull one of them out into
/// a nested loop.
///
/// This is important for code that looks like
/// this:
///
/// Loop:
/// ...
/// br cond, Loop, Next
/// ...
/// br cond2, Loop, Out
///
/// To identify this common case, we look at the PHI nodes in the header of the
/// loop. PHI nodes with unchanging values on one backedge correspond to values
/// that change in the "outer" loop, but not in the "inner" loop.
///
/// If we are able to separate out a loop, return the new outer loop that was
/// created.
///
static Loop *separateNestedLoop(Loop *L, BasicBlock *Preheader,
AliasAnalysis *AA, DominatorTree *DT,
LoopInfo *LI, ScalarEvolution *SE, Pass *PP,
AssumptionCache *AC) {
// Don't try to separate loops without a preheader.
if (!Preheader)
return nullptr;
// The header is not a landing pad; preheader insertion should ensure this.
assert(!L->getHeader()->isLandingPad() &&
"Can't insert backedge to landing pad");
PHINode *PN = findPHIToPartitionLoops(L, AA, DT, AC);
if (!PN) return nullptr; // No known way to partition.
// Pull out all predecessors that have varying values in the loop. This
// handles the case when a PHI node has multiple instances of itself as
// arguments.
SmallVector<BasicBlock*, 8> OuterLoopPreds;
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
if (PN->getIncomingValue(i) != PN ||
!L->contains(PN->getIncomingBlock(i))) {
// We can't split indirectbr edges.
if (isa<IndirectBrInst>(PN->getIncomingBlock(i)->getTerminator()))
return nullptr;
OuterLoopPreds.push_back(PN->getIncomingBlock(i));
}
}
DEBUG(dbgs() << "LoopSimplify: Splitting out a new outer loop\n");
// If ScalarEvolution is around and knows anything about values in
// this loop, tell it to forget them, because we're about to
// substantially change it.
if (SE)
SE->forgetLoop(L);
bool PreserveLCSSA = PP->mustPreserveAnalysisID(LCSSAID);
BasicBlock *Header = L->getHeader();
BasicBlock *NewBB = SplitBlockPredecessors(Header, OuterLoopPreds, ".outer",
AA, DT, LI, PreserveLCSSA);
// Make sure that NewBB is put someplace intelligent, which doesn't mess up
// code layout too horribly.
placeSplitBlockCarefully(NewBB, OuterLoopPreds, L);
// Create the new outer loop.
Loop *NewOuter = new Loop();
// Change the parent loop to use the outer loop as its child now.
if (Loop *Parent = L->getParentLoop())
Parent->replaceChildLoopWith(L, NewOuter);
else
LI->changeTopLevelLoop(L, NewOuter);
// L is now a subloop of our outer loop.
NewOuter->addChildLoop(L);
for (Loop::block_iterator I = L->block_begin(), E = L->block_end();
I != E; ++I)
NewOuter->addBlockEntry(*I);
// Now reset the header in L, which had been moved by
// SplitBlockPredecessors for the outer loop.
L->moveToHeader(Header);
// Determine which blocks should stay in L and which should be moved out to
// the Outer loop now.
std::set<BasicBlock*> BlocksInL;
for (pred_iterator PI=pred_begin(Header), E = pred_end(Header); PI!=E; ++PI) {
BasicBlock *P = *PI;
if (DT->dominates(Header, P))
addBlockAndPredsToSet(P, Header, BlocksInL);
}
// Scan all of the loop children of L, moving them to OuterLoop if they are
// not part of the inner loop.
const std::vector<Loop*> &SubLoops = L->getSubLoops();
for (size_t I = 0; I != SubLoops.size(); )
if (BlocksInL.count(SubLoops[I]->getHeader()))
++I; // Loop remains in L
else
NewOuter->addChildLoop(L->removeChildLoop(SubLoops.begin() + I));
// Now that we know which blocks are in L and which need to be moved to
// OuterLoop, move any blocks that need it.
for (unsigned i = 0; i != L->getBlocks().size(); ++i) {
BasicBlock *BB = L->getBlocks()[i];
if (!BlocksInL.count(BB)) {
// Move this block to the parent, updating the exit blocks sets
L->removeBlockFromLoop(BB);
if ((*LI)[BB] == L)
LI->changeLoopFor(BB, NewOuter);
--i;
}
}
return NewOuter;
}
/// \brief This method is called when the specified loop has more than one
/// backedge in it.
///
/// If this occurs, revector all of these backedges to target a new basic block
/// and have that block branch to the loop header. This ensures that loops
/// have exactly one backedge.
static BasicBlock *insertUniqueBackedgeBlock(Loop *L, BasicBlock *Preheader,
AliasAnalysis *AA,
DominatorTree *DT, LoopInfo *LI) {
assert(L->getNumBackEdges() > 1 && "Must have > 1 backedge!");
// Get information about the loop
BasicBlock *Header = L->getHeader();
Function *F = Header->getParent();
// Unique backedge insertion currently depends on having a preheader.
if (!Preheader)
return nullptr;
// The header is not a landing pad; preheader insertion should ensure this.
assert(!Header->isLandingPad() && "Can't insert backedge to landing pad");
// Figure out which basic blocks contain back-edges to the loop header.
std::vector<BasicBlock*> BackedgeBlocks;
for (pred_iterator I = pred_begin(Header), E = pred_end(Header); I != E; ++I){
BasicBlock *P = *I;
// Indirectbr edges cannot be split, so we must fail if we find one.
if (isa<IndirectBrInst>(P->getTerminator()))
return nullptr;
if (P != Preheader) BackedgeBlocks.push_back(P);
}
// Create and insert the new backedge block...
BasicBlock *BEBlock = BasicBlock::Create(Header->getContext(),
Header->getName() + ".backedge", F);
BranchInst *BETerminator = BranchInst::Create(Header, BEBlock);
BETerminator->setDebugLoc(Header->getFirstNonPHI()->getDebugLoc());
DEBUG(dbgs() << "LoopSimplify: Inserting unique backedge block "
<< BEBlock->getName() << "\n");
// Move the new backedge block to right after the last backedge block.
Function::iterator InsertPos = BackedgeBlocks.back(); ++InsertPos;
F->getBasicBlockList().splice(InsertPos, F->getBasicBlockList(), BEBlock);
// Now that the block has been inserted into the function, create PHI nodes in
// the backedge block which correspond to any PHI nodes in the header block.
for (BasicBlock::iterator I = Header->begin(); isa<PHINode>(I); ++I) {
PHINode *PN = cast<PHINode>(I);
PHINode *NewPN = PHINode::Create(PN->getType(), BackedgeBlocks.size(),
PN->getName()+".be", BETerminator);
// Loop over the PHI node, moving all entries except the one for the
// preheader over to the new PHI node.
unsigned PreheaderIdx = ~0U;
bool HasUniqueIncomingValue = true;
Value *UniqueValue = nullptr;
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
BasicBlock *IBB = PN->getIncomingBlock(i);
Value *IV = PN->getIncomingValue(i);
if (IBB == Preheader) {
PreheaderIdx = i;
} else {
NewPN->addIncoming(IV, IBB);
if (HasUniqueIncomingValue) {
if (!UniqueValue)
UniqueValue = IV;
else if (UniqueValue != IV)
HasUniqueIncomingValue = false;
}
}
}
// Delete all of the incoming values from the old PN except the preheader's
assert(PreheaderIdx != ~0U && "PHI has no preheader entry??");
if (PreheaderIdx != 0) {
PN->setIncomingValue(0, PN->getIncomingValue(PreheaderIdx));
PN->setIncomingBlock(0, PN->getIncomingBlock(PreheaderIdx));
}
// Nuke all entries except the zero'th.
for (unsigned i = 0, e = PN->getNumIncomingValues()-1; i != e; ++i)
PN->removeIncomingValue(e-i, false);
// Finally, add the newly constructed PHI node as the entry for the BEBlock.
PN->addIncoming(NewPN, BEBlock);
// As an optimization, if all incoming values in the new PhiNode (which is a
// subset of the incoming values of the old PHI node) have the same value,
// eliminate the PHI Node.
if (HasUniqueIncomingValue) {
NewPN->replaceAllUsesWith(UniqueValue);
if (AA) AA->deleteValue(NewPN);
BEBlock->getInstList().erase(NewPN);
}
}
// Now that all of the PHI nodes have been inserted and adjusted, modify the
// backedge blocks to just to the BEBlock instead of the header.
for (unsigned i = 0, e = BackedgeBlocks.size(); i != e; ++i) {
TerminatorInst *TI = BackedgeBlocks[i]->getTerminator();
for (unsigned Op = 0, e = TI->getNumSuccessors(); Op != e; ++Op)
if (TI->getSuccessor(Op) == Header)
TI->setSuccessor(Op, BEBlock);
}
//===--- Update all analyses which we must preserve now -----------------===//
// Update Loop Information - we know that this block is now in the current
// loop and all parent loops.
L->addBasicBlockToLoop(BEBlock, *LI);
// Update dominator information
DT->splitBlock(BEBlock);
return BEBlock;
}
/// \brief Simplify one loop and queue further loops for simplification.
///
/// FIXME: Currently this accepts both lots of analyses that it uses and a raw
/// Pass pointer. The Pass pointer is used by numerous utilities to update
/// specific analyses. Rather than a pass it would be much cleaner and more
/// explicit if they accepted the analysis directly and then updated it.
static bool simplifyOneLoop(Loop *L, SmallVectorImpl<Loop *> &Worklist,
AliasAnalysis *AA, DominatorTree *DT, LoopInfo *LI,
ScalarEvolution *SE, Pass *PP,
AssumptionCache *AC) {
bool Changed = false;
ReprocessLoop:
// Check to see that no blocks (other than the header) in this loop have
// predecessors that are not in the loop. This is not valid for natural
// loops, but can occur if the blocks are unreachable. Since they are
// unreachable we can just shamelessly delete those CFG edges!
for (Loop::block_iterator BB = L->block_begin(), E = L->block_end();
BB != E; ++BB) {
if (*BB == L->getHeader()) continue;
SmallPtrSet<BasicBlock*, 4> BadPreds;
for (pred_iterator PI = pred_begin(*BB),
PE = pred_end(*BB); PI != PE; ++PI) {
BasicBlock *P = *PI;
if (!L->contains(P))
BadPreds.insert(P);
}
// Delete each unique out-of-loop (and thus dead) predecessor.
for (BasicBlock *P : BadPreds) {
DEBUG(dbgs() << "LoopSimplify: Deleting edge from dead predecessor "
<< P->getName() << "\n");
// Inform each successor of each dead pred.
for (succ_iterator SI = succ_begin(P), SE = succ_end(P); SI != SE; ++SI)
(*SI)->removePredecessor(P);
// Zap the dead pred's terminator and replace it with unreachable.
TerminatorInst *TI = P->getTerminator();
TI->replaceAllUsesWith(UndefValue::get(TI->getType()));
P->getTerminator()->eraseFromParent();
new UnreachableInst(P->getContext(), P);
Changed = true;
}
}
// If there are exiting blocks with branches on undef, resolve the undef in
// the direction which will exit the loop. This will help simplify loop
// trip count computations.
SmallVector<BasicBlock*, 8> ExitingBlocks;
L->getExitingBlocks(ExitingBlocks);
for (SmallVectorImpl<BasicBlock *>::iterator I = ExitingBlocks.begin(),
E = ExitingBlocks.end(); I != E; ++I)
if (BranchInst *BI = dyn_cast<BranchInst>((*I)->getTerminator()))
if (BI->isConditional()) {
if (UndefValue *Cond = dyn_cast<UndefValue>(BI->getCondition())) {
DEBUG(dbgs() << "LoopSimplify: Resolving \"br i1 undef\" to exit in "
<< (*I)->getName() << "\n");
BI->setCondition(ConstantInt::get(Cond->getType(),
!L->contains(BI->getSuccessor(0))));
// This may make the loop analyzable, force SCEV recomputation.
if (SE)
SE->forgetLoop(L);
Changed = true;
}
}
// Does the loop already have a preheader? If so, don't insert one.
BasicBlock *Preheader = L->getLoopPreheader();
if (!Preheader) {
Preheader = InsertPreheaderForLoop(L, PP);
if (Preheader) {
++NumInserted;
Changed = true;
}
}
// Next, check to make sure that all exit nodes of the loop only have
// predecessors that are inside of the loop. This check guarantees that the
// loop preheader/header will dominate the exit blocks. If the exit block has
// predecessors from outside of the loop, split the edge now.
SmallVector<BasicBlock*, 8> ExitBlocks;
L->getExitBlocks(ExitBlocks);
SmallSetVector<BasicBlock *, 8> ExitBlockSet(ExitBlocks.begin(),
ExitBlocks.end());
for (SmallSetVector<BasicBlock *, 8>::iterator I = ExitBlockSet.begin(),
E = ExitBlockSet.end(); I != E; ++I) {
BasicBlock *ExitBlock = *I;
for (pred_iterator PI = pred_begin(ExitBlock), PE = pred_end(ExitBlock);
PI != PE; ++PI)
// Must be exactly this loop: no subloops, parent loops, or non-loop preds
// allowed.
if (!L->contains(*PI)) {
if (rewriteLoopExitBlock(L, ExitBlock, AA, DT, LI, PP)) {
++NumInserted;
Changed = true;
}
break;
}
}
// If the header has more than two predecessors at this point (from the
// preheader and from multiple backedges), we must adjust the loop.
BasicBlock *LoopLatch = L->getLoopLatch();
if (!LoopLatch) {
// If this is really a nested loop, rip it out into a child loop. Don't do
// this for loops with a giant number of backedges, just factor them into a
// common backedge instead.
if (L->getNumBackEdges() < 8
&& false // HLSL Change - don't add nested loop.
) {
if (Loop *OuterL =
separateNestedLoop(L, Preheader, AA, DT, LI, SE, PP, AC)) {
++NumNested;
// Enqueue the outer loop as it should be processed next in our
// depth-first nest walk.
Worklist.push_back(OuterL);
// This is a big restructuring change, reprocess the whole loop.
Changed = true;
// GCC doesn't tail recursion eliminate this.
// FIXME: It isn't clear we can't rely on LLVM to TRE this.
goto ReprocessLoop;
}
}
// If we either couldn't, or didn't want to, identify nesting of the loops,
// insert a new block that all backedges target, then make it jump to the
// loop header.
LoopLatch = insertUniqueBackedgeBlock(L, Preheader, AA, DT, LI);
if (LoopLatch) {
++NumInserted;
Changed = true;
}
}
const DataLayout &DL = L->getHeader()->getModule()->getDataLayout();
// Scan over the PHI nodes in the loop header. Since they now have only two
// incoming values (the loop is canonicalized), we may have simplified the PHI
// down to 'X = phi [X, Y]', which should be replaced with 'Y'.
PHINode *PN;
for (BasicBlock::iterator I = L->getHeader()->begin();
(PN = dyn_cast<PHINode>(I++)); )
if (Value *V = SimplifyInstruction(PN, DL, nullptr, DT, AC)) {
if (AA) AA->deleteValue(PN);
if (SE) SE->forgetValue(PN);
PN->replaceAllUsesWith(V);
PN->eraseFromParent();
}
// If this loop has multiple exits and the exits all go to the same
// block, attempt to merge the exits. This helps several passes, such
// as LoopRotation, which do not support loops with multiple exits.
// SimplifyCFG also does this (and this code uses the same utility
// function), however this code is loop-aware, where SimplifyCFG is
// not. That gives it the advantage of being able to hoist
// loop-invariant instructions out of the way to open up more
// opportunities, and the disadvantage of having the responsibility
// to preserve dominator information.
bool UniqueExit = true;
if (!ExitBlocks.empty())
for (unsigned i = 1, e = ExitBlocks.size(); i != e; ++i)
if (ExitBlocks[i] != ExitBlocks[0]) {
UniqueExit = false;
break;
}
if (UniqueExit) {
for (unsigned i = 0, e = ExitingBlocks.size(); i != e; ++i) {
BasicBlock *ExitingBlock = ExitingBlocks[i];
if (!ExitingBlock->getSinglePredecessor()) continue;
BranchInst *BI = dyn_cast<BranchInst>(ExitingBlock->getTerminator());
if (!BI || !BI->isConditional()) continue;
CmpInst *CI = dyn_cast<CmpInst>(BI->getCondition());
if (!CI || CI->getParent() != ExitingBlock) continue;
// Attempt to hoist out all instructions except for the
// comparison and the branch.
bool AllInvariant = true;
bool AnyInvariant = false;
for (BasicBlock::iterator I = ExitingBlock->begin(); &*I != BI; ) {
Instruction *Inst = I++;
// Skip debug info intrinsics.
if (isa<DbgInfoIntrinsic>(Inst))
continue;
if (Inst == CI)
continue;
if (!L->makeLoopInvariant(Inst, AnyInvariant,
Preheader ? Preheader->getTerminator()
: nullptr)) {
AllInvariant = false;
break;
}
}
if (AnyInvariant) {
Changed = true;
// The loop disposition of all SCEV expressions that depend on any
// hoisted values have also changed.
if (SE)
SE->forgetLoopDispositions(L);
}
if (!AllInvariant) continue;
// The block has now been cleared of all instructions except for
// a comparison and a conditional branch. SimplifyCFG may be able
// to fold it now.
if (!FoldBranchToCommonDest(BI))
continue;
// Success. The block is now dead, so remove it from the loop,
// update the dominator tree and delete it.
DEBUG(dbgs() << "LoopSimplify: Eliminating exiting block "
<< ExitingBlock->getName() << "\n");
// Notify ScalarEvolution before deleting this block. Currently assume the
// parent loop doesn't change (spliting edges doesn't count). If blocks,
// CFG edges, or other values in the parent loop change, then we need call
// to forgetLoop() for the parent instead.
if (SE)
SE->forgetLoop(L);
assert(pred_begin(ExitingBlock) == pred_end(ExitingBlock));
Changed = true;
LI->removeBlock(ExitingBlock);
DomTreeNode *Node = DT->getNode(ExitingBlock);
const std::vector<DomTreeNodeBase<BasicBlock> *> &Children =
Node->getChildren();
while (!Children.empty()) {
DomTreeNode *Child = Children.front();
DT->changeImmediateDominator(Child, Node->getIDom());
}
DT->eraseNode(ExitingBlock);
BI->getSuccessor(0)->removePredecessor(ExitingBlock);
BI->getSuccessor(1)->removePredecessor(ExitingBlock);
ExitingBlock->eraseFromParent();
}
}
return Changed;
}
bool llvm::simplifyLoop(Loop *L, DominatorTree *DT, LoopInfo *LI, Pass *PP,
AliasAnalysis *AA, ScalarEvolution *SE,
AssumptionCache *AC) {
bool Changed = false;
// Worklist maintains our depth-first queue of loops in this nest to process.
SmallVector<Loop *, 4> Worklist;
Worklist.push_back(L);
// Walk the worklist from front to back, pushing newly found sub loops onto
// the back. This will let us process loops from back to front in depth-first
// order. We can use this simple process because loops form a tree.
for (unsigned Idx = 0; Idx != Worklist.size(); ++Idx) {
Loop *L2 = Worklist[Idx];
Worklist.append(L2->begin(), L2->end());
}
while (!Worklist.empty())
Changed |= simplifyOneLoop(Worklist.pop_back_val(), Worklist, AA, DT, LI,
SE, PP, AC);
return Changed;
}
INITIALIZE_PASS_BEGIN(LoopSimplify, "loop-simplify",
"Canonicalize natural loops", false, false)
INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
INITIALIZE_PASS_END(LoopSimplify, "loop-simplify",
"Canonicalize natural loops", false, false)
// Publicly exposed interface to pass...
Pass *llvm::createLoopSimplifyPass() { return new LoopSimplify(); }
LoopSimplify::LoopSimplify() : FunctionPass(ID) {
initializeLoopSimplifyPass(*PassRegistry::getPassRegistry());
}
void LoopSimplify::getAnalysisUsage(AnalysisUsage& AU) const {
AU.addRequired<AssumptionCacheTracker>();
// We need loop information to identify the loops...
AU.addRequired<DominatorTreeWrapperPass>();
AU.addPreserved<DominatorTreeWrapperPass>();
AU.addRequired<LoopInfoWrapperPass>();
AU.addPreserved<LoopInfoWrapperPass>();
AU.addPreserved<AliasAnalysis>();
AU.addPreserved<ScalarEvolution>();
AU.addPreserved<DependenceAnalysis>();
AU.addPreservedID(BreakCriticalEdgesID); // No critical edges added.
}
/// runOnFunction - Run down all loops in the CFG (recursively, but we could do
/// it in any convenient order) inserting preheaders...
///
bool LoopSimplify::runOnFunction(Function &F) {
bool Changed = false;
AA = getAnalysisIfAvailable<AliasAnalysis>();
LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
SE = getAnalysisIfAvailable<ScalarEvolution>();
AC = &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
// Simplify each loop nest in the function.
for (LoopInfo::iterator I = LI->begin(), E = LI->end(); I != E; ++I)
Changed |= simplifyLoop(*I, DT, LI, this, AA, SE, AC);
return Changed;
}
// FIXME: Restore this code when we re-enable verification in verifyAnalysis
// below.
#if 0
static void verifyLoop(Loop *L) {
// Verify subloops.
for (Loop::iterator I = L->begin(), E = L->end(); I != E; ++I)
verifyLoop(*I);
// It used to be possible to just assert L->isLoopSimplifyForm(), however
// with the introduction of indirectbr, there are now cases where it's
// not possible to transform a loop as necessary. We can at least check
// that there is an indirectbr near any time there's trouble.
// Indirectbr can interfere with preheader and unique backedge insertion.
if (!L->getLoopPreheader() || !L->getLoopLatch()) {
bool HasIndBrPred = false;
for (pred_iterator PI = pred_begin(L->getHeader()),
PE = pred_end(L->getHeader()); PI != PE; ++PI)
if (isa<IndirectBrInst>((*PI)->getTerminator())) {
HasIndBrPred = true;
break;
}
assert(HasIndBrPred &&
"LoopSimplify has no excuse for missing loop header info!");
(void)HasIndBrPred;
}
// Indirectbr can interfere with exit block canonicalization.
if (!L->hasDedicatedExits()) {
bool HasIndBrExiting = false;
SmallVector<BasicBlock*, 8> ExitingBlocks;
L->getExitingBlocks(ExitingBlocks);
for (unsigned i = 0, e = ExitingBlocks.size(); i != e; ++i) {
if (isa<IndirectBrInst>((ExitingBlocks[i])->getTerminator())) {
HasIndBrExiting = true;
break;
}
}
assert(HasIndBrExiting &&
"LoopSimplify has no excuse for missing exit block info!");
(void)HasIndBrExiting;
}
}
#endif
void LoopSimplify::verifyAnalysis() const {
// FIXME: This routine is being called mid-way through the loop pass manager
// as loop passes destroy this analysis. That's actually fine, but we have no
// way of expressing that here. Once all of the passes that destroy this are
// hoisted out of the loop pass manager we can add back verification here.
#if 0
for (LoopInfo::iterator I = LI->begin(), E = LI->end(); I != E; ++I)
verifyLoop(*I);
#endif
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/LoopVersioning.cpp | //===- LoopVersioning.cpp - Utility to version a loop ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines a utility class to perform loop versioning. The versioned
// loop speculates that otherwise may-aliasing memory accesses don't overlap and
// emits checks to prove this.
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/LoopAccessAnalysis.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/IR/Dominators.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Cloning.h"
#include "llvm/Transforms/Utils/LoopVersioning.h"
using namespace llvm;
LoopVersioning::LoopVersioning(const LoopAccessInfo &LAI, Loop *L, LoopInfo *LI,
DominatorTree *DT,
const SmallVector<int, 8> *PtrToPartition)
: VersionedLoop(L), NonVersionedLoop(nullptr),
PtrToPartition(PtrToPartition), LAI(LAI), LI(LI), DT(DT) {
assert(L->getExitBlock() && "No single exit block");
assert(L->getLoopPreheader() && "No preheader");
}
bool LoopVersioning::needsRuntimeChecks() const {
return LAI.getRuntimePointerChecking()->needsAnyChecking(PtrToPartition);
}
void LoopVersioning::versionLoop(Pass *P) {
Instruction *FirstCheckInst;
Instruction *MemRuntimeCheck;
// Add the memcheck in the original preheader (this is empty initially).
BasicBlock *MemCheckBB = VersionedLoop->getLoopPreheader();
std::tie(FirstCheckInst, MemRuntimeCheck) =
LAI.addRuntimeCheck(MemCheckBB->getTerminator(), PtrToPartition);
assert(MemRuntimeCheck && "called even though needsAnyChecking = false");
// Rename the block to make the IR more readable.
MemCheckBB->setName(VersionedLoop->getHeader()->getName() + ".lver.memcheck");
// Create empty preheader for the loop (and after cloning for the
// non-versioned loop).
BasicBlock *PH = SplitBlock(MemCheckBB, MemCheckBB->getTerminator(), DT, LI);
PH->setName(VersionedLoop->getHeader()->getName() + ".ph");
// Clone the loop including the preheader.
//
// FIXME: This does not currently preserve SimplifyLoop because the exit
// block is a join between the two loops.
SmallVector<BasicBlock *, 8> NonVersionedLoopBlocks;
NonVersionedLoop =
cloneLoopWithPreheader(PH, MemCheckBB, VersionedLoop, VMap, ".lver.orig",
LI, DT, NonVersionedLoopBlocks);
remapInstructionsInBlocks(NonVersionedLoopBlocks, VMap);
// Insert the conditional branch based on the result of the memchecks.
Instruction *OrigTerm = MemCheckBB->getTerminator();
BranchInst::Create(NonVersionedLoop->getLoopPreheader(),
VersionedLoop->getLoopPreheader(), MemRuntimeCheck,
OrigTerm);
OrigTerm->eraseFromParent();
// The loops merge in the original exit block. This is now dominated by the
// memchecking block.
DT->changeImmediateDominator(VersionedLoop->getExitBlock(), MemCheckBB);
}
void LoopVersioning::addPHINodes(
const SmallVectorImpl<Instruction *> &DefsUsedOutside) {
BasicBlock *PHIBlock = VersionedLoop->getExitBlock();
assert(PHIBlock && "No single successor to loop exit block");
for (auto *Inst : DefsUsedOutside) {
auto *NonVersionedLoopInst = cast<Instruction>(VMap[Inst]);
PHINode *PN;
// First see if we have a single-operand PHI with the value defined by the
// original loop.
for (auto I = PHIBlock->begin(); (PN = dyn_cast<PHINode>(I)); ++I) {
assert(PN->getNumOperands() == 1 &&
"Exit block should only have on predecessor");
if (PN->getIncomingValue(0) == Inst)
break;
}
// If not create it.
if (!PN) {
PN = PHINode::Create(Inst->getType(), 2, Inst->getName() + ".lver",
PHIBlock->begin());
for (auto *User : Inst->users())
if (!VersionedLoop->contains(cast<Instruction>(User)->getParent()))
User->replaceUsesOfWith(Inst, PN);
PN->addIncoming(Inst, VersionedLoop->getExitingBlock());
}
// Add the new incoming value from the non-versioned loop.
PN->addIncoming(NonVersionedLoopInst, NonVersionedLoop->getExitingBlock());
}
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/LoopUnrollRuntime.cpp | //===-- UnrollLoopRuntime.cpp - Runtime Loop unrolling utilities ----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements some loop unrolling utilities for loops with run-time
// trip counts. See LoopUnroll.cpp for unrolling loops with compile-time
// trip counts.
//
// The functions in this file are used to generate extra code when the
// run-time trip count modulo the unroll factor is not 0. When this is the
// case, we need to generate code to execute these 'left over' iterations.
//
// The current strategy generates an if-then-else sequence prior to the
// unrolled loop to execute the 'left over' iterations. Other strategies
// include generate a loop before or after the unrolled loop.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/UnrollLoop.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/LoopIterator.h"
#include "llvm/Analysis/LoopPass.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/ScalarEvolutionExpander.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Cloning.h"
#include <algorithm>
using namespace llvm;
#define DEBUG_TYPE "loop-unroll"
STATISTIC(NumRuntimeUnrolled,
"Number of loops unrolled with run-time trip counts");
/// Connect the unrolling prolog code to the original loop.
/// The unrolling prolog code contains code to execute the
/// 'extra' iterations if the run-time trip count modulo the
/// unroll count is non-zero.
///
/// This function performs the following:
/// - Create PHI nodes at prolog end block to combine values
/// that exit the prolog code and jump around the prolog.
/// - Add a PHI operand to a PHI node at the loop exit block
/// for values that exit the prolog and go around the loop.
/// - Branch around the original loop if the trip count is less
/// than the unroll factor.
///
static void ConnectProlog(Loop *L, Value *BECount, unsigned Count,
BasicBlock *LastPrologBB, BasicBlock *PrologEnd,
BasicBlock *OrigPH, BasicBlock *NewPH,
ValueToValueMapTy &VMap, AliasAnalysis *AA,
DominatorTree *DT, LoopInfo *LI, Pass *P) {
BasicBlock *Latch = L->getLoopLatch();
assert(Latch && "Loop must have a latch");
// Create a PHI node for each outgoing value from the original loop
// (which means it is an outgoing value from the prolog code too).
// The new PHI node is inserted in the prolog end basic block.
// The new PHI name is added as an operand of a PHI node in either
// the loop header or the loop exit block.
for (succ_iterator SBI = succ_begin(Latch), SBE = succ_end(Latch);
SBI != SBE; ++SBI) {
for (BasicBlock::iterator BBI = (*SBI)->begin();
PHINode *PN = dyn_cast<PHINode>(BBI); ++BBI) {
// Add a new PHI node to the prolog end block and add the
// appropriate incoming values.
PHINode *NewPN = PHINode::Create(PN->getType(), 2, PN->getName()+".unr",
PrologEnd->getTerminator());
// Adding a value to the new PHI node from the original loop preheader.
// This is the value that skips all the prolog code.
if (L->contains(PN)) {
NewPN->addIncoming(PN->getIncomingValueForBlock(NewPH), OrigPH);
} else {
NewPN->addIncoming(UndefValue::get(PN->getType()), OrigPH);
}
Value *V = PN->getIncomingValueForBlock(Latch);
if (Instruction *I = dyn_cast<Instruction>(V)) {
if (L->contains(I)) {
V = VMap[I];
}
}
// Adding a value to the new PHI node from the last prolog block
// that was created.
NewPN->addIncoming(V, LastPrologBB);
// Update the existing PHI node operand with the value from the
// new PHI node. How this is done depends on if the existing
// PHI node is in the original loop block, or the exit block.
if (L->contains(PN)) {
PN->setIncomingValue(PN->getBasicBlockIndex(NewPH), NewPN);
} else {
PN->addIncoming(NewPN, PrologEnd);
}
}
}
// Create a branch around the orignal loop, which is taken if there are no
// iterations remaining to be executed after running the prologue.
Instruction *InsertPt = PrologEnd->getTerminator();
IRBuilder<> B(InsertPt);
assert(Count != 0 && "nonsensical Count!");
// If BECount <u (Count - 1) then (BECount + 1) & (Count - 1) == (BECount + 1)
// (since Count is a power of 2). This means %xtraiter is (BECount + 1) and
// and all of the iterations of this loop were executed by the prologue. Note
// that if BECount <u (Count - 1) then (BECount + 1) cannot unsigned-overflow.
Value *BrLoopExit =
B.CreateICmpULT(BECount, ConstantInt::get(BECount->getType(), Count - 1));
BasicBlock *Exit = L->getUniqueExitBlock();
assert(Exit && "Loop must have a single exit block only");
// Split the exit to maintain loop canonicalization guarantees
SmallVector<BasicBlock*, 4> Preds(pred_begin(Exit), pred_end(Exit));
SplitBlockPredecessors(Exit, Preds, ".unr-lcssa", AA, DT, LI,
P->mustPreserveAnalysisID(LCSSAID));
// Add the branch to the exit block (around the unrolled loop)
B.CreateCondBr(BrLoopExit, Exit, NewPH);
InsertPt->eraseFromParent();
}
/// Create a clone of the blocks in a loop and connect them together.
/// If UnrollProlog is true, loop structure will not be cloned, otherwise a new
/// loop will be created including all cloned blocks, and the iterator of it
/// switches to count NewIter down to 0.
///
static void CloneLoopBlocks(Loop *L, Value *NewIter, const bool UnrollProlog,
BasicBlock *InsertTop, BasicBlock *InsertBot,
std::vector<BasicBlock *> &NewBlocks,
LoopBlocksDFS &LoopBlocks, ValueToValueMapTy &VMap,
LoopInfo *LI) {
BasicBlock *Preheader = L->getLoopPreheader();
BasicBlock *Header = L->getHeader();
BasicBlock *Latch = L->getLoopLatch();
Function *F = Header->getParent();
LoopBlocksDFS::RPOIterator BlockBegin = LoopBlocks.beginRPO();
LoopBlocksDFS::RPOIterator BlockEnd = LoopBlocks.endRPO();
Loop *NewLoop = 0;
Loop *ParentLoop = L->getParentLoop();
if (!UnrollProlog) {
NewLoop = new Loop();
if (ParentLoop)
ParentLoop->addChildLoop(NewLoop);
else
LI->addTopLevelLoop(NewLoop);
}
// For each block in the original loop, create a new copy,
// and update the value map with the newly created values.
for (LoopBlocksDFS::RPOIterator BB = BlockBegin; BB != BlockEnd; ++BB) {
BasicBlock *NewBB = CloneBasicBlock(*BB, VMap, ".prol", F);
NewBlocks.push_back(NewBB);
if (NewLoop)
NewLoop->addBasicBlockToLoop(NewBB, *LI);
else if (ParentLoop)
ParentLoop->addBasicBlockToLoop(NewBB, *LI);
VMap[*BB] = NewBB;
if (Header == *BB) {
// For the first block, add a CFG connection to this newly
// created block.
InsertTop->getTerminator()->setSuccessor(0, NewBB);
}
if (Latch == *BB) {
// For the last block, if UnrollProlog is true, create a direct jump to
// InsertBot. If not, create a loop back to cloned head.
VMap.erase((*BB)->getTerminator());
BasicBlock *FirstLoopBB = cast<BasicBlock>(VMap[Header]);
BranchInst *LatchBR = cast<BranchInst>(NewBB->getTerminator());
IRBuilder<> Builder(LatchBR);
if (UnrollProlog) {
Builder.CreateBr(InsertBot);
} else {
PHINode *NewIdx = PHINode::Create(NewIter->getType(), 2, "prol.iter",
FirstLoopBB->getFirstNonPHI());
Value *IdxSub =
Builder.CreateSub(NewIdx, ConstantInt::get(NewIdx->getType(), 1),
NewIdx->getName() + ".sub");
Value *IdxCmp =
Builder.CreateIsNotNull(IdxSub, NewIdx->getName() + ".cmp");
Builder.CreateCondBr(IdxCmp, FirstLoopBB, InsertBot);
NewIdx->addIncoming(NewIter, InsertTop);
NewIdx->addIncoming(IdxSub, NewBB);
}
LatchBR->eraseFromParent();
}
}
// Change the incoming values to the ones defined in the preheader or
// cloned loop.
for (BasicBlock::iterator I = Header->begin(); isa<PHINode>(I); ++I) {
PHINode *NewPHI = cast<PHINode>(VMap[I]);
if (UnrollProlog) {
VMap[I] = NewPHI->getIncomingValueForBlock(Preheader);
cast<BasicBlock>(VMap[Header])->getInstList().erase(NewPHI);
} else {
unsigned idx = NewPHI->getBasicBlockIndex(Preheader);
NewPHI->setIncomingBlock(idx, InsertTop);
BasicBlock *NewLatch = cast<BasicBlock>(VMap[Latch]);
idx = NewPHI->getBasicBlockIndex(Latch);
Value *InVal = NewPHI->getIncomingValue(idx);
NewPHI->setIncomingBlock(idx, NewLatch);
if (VMap[InVal])
NewPHI->setIncomingValue(idx, VMap[InVal]);
}
}
if (NewLoop) {
// Add unroll disable metadata to disable future unrolling for this loop.
SmallVector<Metadata *, 4> MDs;
// Reserve first location for self reference to the LoopID metadata node.
MDs.push_back(nullptr);
MDNode *LoopID = NewLoop->getLoopID();
if (LoopID) {
// First remove any existing loop unrolling metadata.
for (unsigned i = 1, ie = LoopID->getNumOperands(); i < ie; ++i) {
bool IsUnrollMetadata = false;
MDNode *MD = dyn_cast<MDNode>(LoopID->getOperand(i));
if (MD) {
const MDString *S = dyn_cast<MDString>(MD->getOperand(0));
IsUnrollMetadata = S && S->getString().startswith("llvm.loop.unroll.");
}
if (!IsUnrollMetadata)
MDs.push_back(LoopID->getOperand(i));
}
}
LLVMContext &Context = NewLoop->getHeader()->getContext();
SmallVector<Metadata *, 1> DisableOperands;
DisableOperands.push_back(MDString::get(Context, "llvm.loop.unroll.disable"));
MDNode *DisableNode = MDNode::get(Context, DisableOperands);
MDs.push_back(DisableNode);
MDNode *NewLoopID = MDNode::get(Context, MDs);
// Set operand 0 to refer to the loop id itself.
NewLoopID->replaceOperandWith(0, NewLoopID);
NewLoop->setLoopID(NewLoopID);
}
}
/// Insert code in the prolog code when unrolling a loop with a
/// run-time trip-count.
///
/// This method assumes that the loop unroll factor is total number
/// of loop bodes in the loop after unrolling. (Some folks refer
/// to the unroll factor as the number of *extra* copies added).
/// We assume also that the loop unroll factor is a power-of-two. So, after
/// unrolling the loop, the number of loop bodies executed is 2,
/// 4, 8, etc. Note - LLVM converts the if-then-sequence to a switch
/// instruction in SimplifyCFG.cpp. Then, the backend decides how code for
/// the switch instruction is generated.
///
/// extraiters = tripcount % loopfactor
/// if (extraiters == 0) jump Loop:
/// else jump Prol
/// Prol: LoopBody;
/// extraiters -= 1 // Omitted if unroll factor is 2.
/// if (extraiters != 0) jump Prol: // Omitted if unroll factor is 2.
/// if (tripcount < loopfactor) jump End
/// Loop:
/// ...
/// End:
///
bool llvm::UnrollRuntimeLoopProlog(Loop *L, unsigned Count,
bool AllowExpensiveTripCount, LoopInfo *LI,
LPPassManager *LPM) {
// for now, only unroll loops that contain a single exit
if (!L->getExitingBlock())
return false;
// Make sure the loop is in canonical form, and there is a single
// exit block only.
if (!L->isLoopSimplifyForm() || !L->getUniqueExitBlock())
return false;
// Use Scalar Evolution to compute the trip count. This allows more
// loops to be unrolled than relying on induction var simplification
if (!LPM)
return false;
ScalarEvolution *SE = LPM->getAnalysisIfAvailable<ScalarEvolution>();
if (!SE)
return false;
// Only unroll loops with a computable trip count and the trip count needs
// to be an int value (allowing a pointer type is a TODO item)
const SCEV *BECountSC = SE->getBackedgeTakenCount(L);
if (isa<SCEVCouldNotCompute>(BECountSC) ||
!BECountSC->getType()->isIntegerTy())
return false;
unsigned BEWidth = cast<IntegerType>(BECountSC->getType())->getBitWidth();
// Add 1 since the backedge count doesn't include the first loop iteration
const SCEV *TripCountSC =
SE->getAddExpr(BECountSC, SE->getConstant(BECountSC->getType(), 1));
if (isa<SCEVCouldNotCompute>(TripCountSC))
return false;
BasicBlock *Header = L->getHeader();
const DataLayout &DL = Header->getModule()->getDataLayout();
SCEVExpander Expander(*SE, DL, "loop-unroll");
if (!AllowExpensiveTripCount && Expander.isHighCostExpansion(TripCountSC, L))
return false;
// We only handle cases when the unroll factor is a power of 2.
// Count is the loop unroll factor, the number of extra copies added + 1.
if (!isPowerOf2_32(Count))
return false;
// This constraint lets us deal with an overflowing trip count easily; see the
// comment on ModVal below.
if (Log2_32(Count) > BEWidth)
return false;
// If this loop is nested, then the loop unroller changes the code in
// parent loop, so the Scalar Evolution pass needs to be run again
if (Loop *ParentLoop = L->getParentLoop())
SE->forgetLoop(ParentLoop);
// Grab analyses that we preserve.
auto *DTWP = LPM->getAnalysisIfAvailable<DominatorTreeWrapperPass>();
auto *DT = DTWP ? &DTWP->getDomTree() : nullptr;
BasicBlock *PH = L->getLoopPreheader();
BasicBlock *Latch = L->getLoopLatch();
// It helps to splits the original preheader twice, one for the end of the
// prolog code and one for a new loop preheader
BasicBlock *PEnd = SplitEdge(PH, Header, DT, LI);
BasicBlock *NewPH = SplitBlock(PEnd, PEnd->getTerminator(), DT, LI);
BranchInst *PreHeaderBR = cast<BranchInst>(PH->getTerminator());
// Compute the number of extra iterations required, which is:
// extra iterations = run-time trip count % (loop unroll factor + 1)
Value *TripCount = Expander.expandCodeFor(TripCountSC, TripCountSC->getType(),
PreHeaderBR);
Value *BECount = Expander.expandCodeFor(BECountSC, BECountSC->getType(),
PreHeaderBR);
IRBuilder<> B(PreHeaderBR);
Value *ModVal = B.CreateAnd(TripCount, Count - 1, "xtraiter");
// If ModVal is zero, we know that either
// 1. there are no iteration to be run in the prologue loop
// OR
// 2. the addition computing TripCount overflowed
//
// If (2) is true, we know that TripCount really is (1 << BEWidth) and so the
// number of iterations that remain to be run in the original loop is a
// multiple Count == (1 << Log2(Count)) because Log2(Count) <= BEWidth (we
// explicitly check this above).
Value *BranchVal = B.CreateIsNotNull(ModVal, "lcmp.mod");
// Branch to either the extra iterations or the cloned/unrolled loop
// We will fix up the true branch label when adding loop body copies
B.CreateCondBr(BranchVal, PEnd, PEnd);
assert(PreHeaderBR->isUnconditional() &&
PreHeaderBR->getSuccessor(0) == PEnd &&
"CFG edges in Preheader are not correct");
PreHeaderBR->eraseFromParent();
Function *F = Header->getParent();
// Get an ordered list of blocks in the loop to help with the ordering of the
// cloned blocks in the prolog code
LoopBlocksDFS LoopBlocks(L);
LoopBlocks.perform(LI);
//
// For each extra loop iteration, create a copy of the loop's basic blocks
// and generate a condition that branches to the copy depending on the
// number of 'left over' iterations.
//
std::vector<BasicBlock *> NewBlocks;
ValueToValueMapTy VMap;
bool UnrollPrologue = Count == 2;
// Clone all the basic blocks in the loop. If Count is 2, we don't clone
// the loop, otherwise we create a cloned loop to execute the extra
// iterations. This function adds the appropriate CFG connections.
CloneLoopBlocks(L, ModVal, UnrollPrologue, PH, PEnd, NewBlocks, LoopBlocks,
VMap, LI);
// Insert the cloned blocks into function just before the original loop
F->getBasicBlockList().splice(PEnd, F->getBasicBlockList(), NewBlocks[0],
F->end());
// Rewrite the cloned instruction operands to use the values
// created when the clone is created.
for (unsigned i = 0, e = NewBlocks.size(); i != e; ++i) {
for (BasicBlock::iterator I = NewBlocks[i]->begin(),
E = NewBlocks[i]->end();
I != E; ++I) {
RemapInstruction(I, VMap,
RF_NoModuleLevelChanges | RF_IgnoreMissingEntries);
}
}
// Connect the prolog code to the original loop and update the
// PHI functions.
BasicBlock *LastLoopBB = cast<BasicBlock>(VMap[Latch]);
ConnectProlog(L, BECount, Count, LastLoopBB, PEnd, PH, NewPH, VMap,
/*AliasAnalysis*/ nullptr, DT, LI, LPM->getAsPass());
NumRuntimeUnrolled++;
return true;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/LCSSA.cpp | //===-- LCSSA.cpp - Convert loops into loop-closed SSA form ---------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This pass transforms loops by placing phi nodes at the end of the loops for
// all values that are live across the loop boundary. For example, it turns
// the left into the right code:
//
// for (...) for (...)
// if (c) if (c)
// X1 = ... X1 = ...
// else else
// X2 = ... X2 = ...
// X3 = phi(X1, X2) X3 = phi(X1, X2)
// ... = X3 + 4 X4 = phi(X3)
// ... = X4 + 4
//
// This is still valid LLVM; the extra phi nodes are purely redundant, and will
// be trivially eliminated by InstCombine. The major benefit of this
// transformation is that it makes many other loop optimizations, such as
// LoopUnswitching, simpler.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Scalar.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/LoopPass.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/PredIteratorCache.h"
#include "llvm/Pass.h"
#include "llvm/Transforms/Utils/LoopUtils.h"
#include "llvm/Transforms/Utils/SSAUpdater.h"
using namespace llvm;
#define DEBUG_TYPE "lcssa"
STATISTIC(NumLCSSA, "Number of live out of a loop variables");
/// Return true if the specified block is in the list.
static bool isExitBlock(BasicBlock *BB,
const SmallVectorImpl<BasicBlock *> &ExitBlocks) {
for (unsigned i = 0, e = ExitBlocks.size(); i != e; ++i)
if (ExitBlocks[i] == BB)
return true;
return false;
}
/// Given an instruction in the loop, check to see if it has any uses that are
/// outside the current loop. If so, insert LCSSA PHI nodes and rewrite the
/// uses.
static bool processInstruction(Loop &L, Instruction &Inst, DominatorTree &DT,
const SmallVectorImpl<BasicBlock *> &ExitBlocks,
PredIteratorCache &PredCache, LoopInfo *LI) {
SmallVector<Use *, 16> UsesToRewrite;
BasicBlock *InstBB = Inst.getParent();
for (Use &U : Inst.uses()) {
Instruction *User = cast<Instruction>(U.getUser());
BasicBlock *UserBB = User->getParent();
if (PHINode *PN = dyn_cast<PHINode>(User))
UserBB = PN->getIncomingBlock(U);
if (InstBB != UserBB && !L.contains(UserBB))
UsesToRewrite.push_back(&U);
}
// If there are no uses outside the loop, exit with no change.
if (UsesToRewrite.empty())
return false;
++NumLCSSA; // We are applying the transformation
// Invoke instructions are special in that their result value is not available
// along their unwind edge. The code below tests to see whether DomBB
// dominates
// the value, so adjust DomBB to the normal destination block, which is
// effectively where the value is first usable.
BasicBlock *DomBB = Inst.getParent();
if (InvokeInst *Inv = dyn_cast<InvokeInst>(&Inst))
DomBB = Inv->getNormalDest();
DomTreeNode *DomNode = DT.getNode(DomBB);
SmallVector<PHINode *, 16> AddedPHIs;
SmallVector<PHINode *, 8> PostProcessPHIs;
SSAUpdater SSAUpdate;
SSAUpdate.Initialize(Inst.getType(), Inst.getName());
// Insert the LCSSA phi's into all of the exit blocks dominated by the
// value, and add them to the Phi's map.
for (SmallVectorImpl<BasicBlock *>::const_iterator BBI = ExitBlocks.begin(),
BBE = ExitBlocks.end();
BBI != BBE; ++BBI) {
BasicBlock *ExitBB = *BBI;
if (!DT.dominates(DomNode, DT.getNode(ExitBB)))
continue;
// If we already inserted something for this BB, don't reprocess it.
if (SSAUpdate.HasValueForBlock(ExitBB))
continue;
PHINode *PN = PHINode::Create(Inst.getType(), PredCache.size(ExitBB),
Inst.getName() + ".lcssa", ExitBB->begin());
// Add inputs from inside the loop for this PHI.
for (BasicBlock *Pred : PredCache.get(ExitBB)) {
PN->addIncoming(&Inst, Pred);
// If the exit block has a predecessor not within the loop, arrange for
// the incoming value use corresponding to that predecessor to be
// rewritten in terms of a different LCSSA PHI.
if (!L.contains(Pred))
UsesToRewrite.push_back(
&PN->getOperandUse(PN->getOperandNumForIncomingValue(
PN->getNumIncomingValues() - 1)));
}
AddedPHIs.push_back(PN);
// Remember that this phi makes the value alive in this block.
SSAUpdate.AddAvailableValue(ExitBB, PN);
// LoopSimplify might fail to simplify some loops (e.g. when indirect
// branches are involved). In such situations, it might happen that an exit
// for Loop L1 is the header of a disjoint Loop L2. Thus, when we create
// PHIs in such an exit block, we are also inserting PHIs into L2's header.
// This could break LCSSA form for L2 because these inserted PHIs can also
// have uses outside of L2. Remember all PHIs in such situation as to
// revisit than later on. FIXME: Remove this if indirectbr support into
// LoopSimplify gets improved.
if (auto *OtherLoop = LI->getLoopFor(ExitBB))
if (!L.contains(OtherLoop))
PostProcessPHIs.push_back(PN);
}
// Rewrite all uses outside the loop in terms of the new PHIs we just
// inserted.
for (unsigned i = 0, e = UsesToRewrite.size(); i != e; ++i) {
// If this use is in an exit block, rewrite to use the newly inserted PHI.
// This is required for correctness because SSAUpdate doesn't handle uses in
// the same block. It assumes the PHI we inserted is at the end of the
// block.
Instruction *User = cast<Instruction>(UsesToRewrite[i]->getUser());
BasicBlock *UserBB = User->getParent();
if (PHINode *PN = dyn_cast<PHINode>(User))
UserBB = PN->getIncomingBlock(*UsesToRewrite[i]);
if (isa<PHINode>(UserBB->begin()) && isExitBlock(UserBB, ExitBlocks)) {
// Tell the VHs that the uses changed. This updates SCEV's caches.
if (UsesToRewrite[i]->get()->hasValueHandle())
ValueHandleBase::ValueIsRAUWd(*UsesToRewrite[i], UserBB->begin());
UsesToRewrite[i]->set(UserBB->begin());
continue;
}
// Otherwise, do full PHI insertion.
SSAUpdate.RewriteUse(*UsesToRewrite[i]);
}
// Post process PHI instructions that were inserted into another disjoint loop
// and update their exits properly.
for (auto *I : PostProcessPHIs) {
if (I->use_empty())
continue;
BasicBlock *PHIBB = I->getParent();
Loop *OtherLoop = LI->getLoopFor(PHIBB);
SmallVector<BasicBlock *, 8> EBs;
OtherLoop->getExitBlocks(EBs);
if (EBs.empty())
continue;
// Recurse and re-process each PHI instruction. FIXME: we should really
// convert this entire thing to a worklist approach where we process a
// vector of instructions...
processInstruction(*OtherLoop, *I, DT, EBs, PredCache, LI);
}
// Remove PHI nodes that did not have any uses rewritten.
for (unsigned i = 0, e = AddedPHIs.size(); i != e; ++i) {
if (AddedPHIs[i]->use_empty())
AddedPHIs[i]->eraseFromParent();
}
return true;
}
/// Return true if the specified block dominates at least
/// one of the blocks in the specified list.
static bool
blockDominatesAnExit(BasicBlock *BB,
DominatorTree &DT,
const SmallVectorImpl<BasicBlock *> &ExitBlocks) {
DomTreeNode *DomNode = DT.getNode(BB);
for (unsigned i = 0, e = ExitBlocks.size(); i != e; ++i)
if (DT.dominates(DomNode, DT.getNode(ExitBlocks[i])))
return true;
return false;
}
bool llvm::formLCSSA(Loop &L, DominatorTree &DT, LoopInfo *LI,
ScalarEvolution *SE) {
bool Changed = false;
// Get the set of exiting blocks.
SmallVector<BasicBlock *, 8> ExitBlocks;
L.getExitBlocks(ExitBlocks);
if (ExitBlocks.empty())
return false;
PredIteratorCache PredCache;
// Look at all the instructions in the loop, checking to see if they have uses
// outside the loop. If so, rewrite those uses.
for (Loop::block_iterator BBI = L.block_begin(), BBE = L.block_end();
BBI != BBE; ++BBI) {
BasicBlock *BB = *BBI;
// For large loops, avoid use-scanning by using dominance information: In
// particular, if a block does not dominate any of the loop exits, then none
// of the values defined in the block could be used outside the loop.
if (!blockDominatesAnExit(BB, DT, ExitBlocks))
continue;
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) {
// Reject two common cases fast: instructions with no uses (like stores)
// and instructions with one use that is in the same block as this.
if (I->use_empty() ||
(I->hasOneUse() && I->user_back()->getParent() == BB &&
!isa<PHINode>(I->user_back())))
continue;
Changed |= processInstruction(L, *I, DT, ExitBlocks, PredCache, LI);
}
}
// If we modified the code, remove any caches about the loop from SCEV to
// avoid dangling entries.
// FIXME: This is a big hammer, can we clear the cache more selectively?
if (SE && Changed)
SE->forgetLoop(&L);
assert(L.isLCSSAForm(DT));
return Changed;
}
/// Process a loop nest depth first.
bool llvm::formLCSSARecursively(Loop &L, DominatorTree &DT, LoopInfo *LI,
ScalarEvolution *SE) {
bool Changed = false;
// Recurse depth-first through inner loops.
for (Loop::iterator I = L.begin(), E = L.end(); I != E; ++I)
Changed |= formLCSSARecursively(**I, DT, LI, SE);
Changed |= formLCSSA(L, DT, LI, SE);
return Changed;
}
namespace {
struct LCSSA : public FunctionPass {
static char ID; // Pass identification, replacement for typeid
LCSSA() : FunctionPass(ID) {
initializeLCSSAPass(*PassRegistry::getPassRegistry());
}
// Cached analysis information for the current function.
DominatorTree *DT;
LoopInfo *LI;
ScalarEvolution *SE;
bool runOnFunction(Function &F) override;
/// This transformation requires natural loop information & requires that
/// loop preheaders be inserted into the CFG. It maintains both of these,
/// as well as the CFG. It also requires dominator information.
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.setPreservesCFG();
AU.addRequired<DominatorTreeWrapperPass>();
AU.addRequired<LoopInfoWrapperPass>();
AU.addPreservedID(LoopSimplifyID);
AU.addPreserved<AliasAnalysis>();
AU.addPreserved<ScalarEvolution>();
}
};
}
char LCSSA::ID = 0;
INITIALIZE_PASS_BEGIN(LCSSA, "lcssa", "Loop-Closed SSA Form Pass", false, false)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
INITIALIZE_PASS_END(LCSSA, "lcssa", "Loop-Closed SSA Form Pass", false, false)
Pass *llvm::createLCSSAPass() { return new LCSSA(); }
char &llvm::LCSSAID = LCSSA::ID;
/// Process all loops in the function, inner-most out.
bool LCSSA::runOnFunction(Function &F) {
bool Changed = false;
LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
SE = getAnalysisIfAvailable<ScalarEvolution>();
// Simplify each loop nest in the function.
for (LoopInfo::iterator I = LI->begin(), E = LI->end(); I != E; ++I)
Changed |= formLCSSARecursively(**I, *DT, LI, SE);
return Changed;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/DemoteRegToStack.cpp | //===- DemoteRegToStack.cpp - Move a virtual register to the stack --------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/Analysis/CFG.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Type.h"
#include "llvm/Transforms/Utils/Local.h"
using namespace llvm;
/// DemoteRegToStack - This function takes a virtual register computed by an
/// Instruction and replaces it with a slot in the stack frame, allocated via
/// alloca. This allows the CFG to be changed around without fear of
/// invalidating the SSA information for the value. It returns the pointer to
/// the alloca inserted to create a stack slot for I.
AllocaInst *llvm::DemoteRegToStack(Instruction &I, bool VolatileLoads,
Instruction *AllocaPoint) {
if (I.use_empty()) {
I.eraseFromParent();
return nullptr;
}
// Create a stack slot to hold the value.
AllocaInst *Slot;
if (AllocaPoint) {
Slot = new AllocaInst(I.getType(), nullptr,
I.getName()+".reg2mem", AllocaPoint);
} else {
Function *F = I.getParent()->getParent();
Slot = new AllocaInst(I.getType(), nullptr, I.getName()+".reg2mem",
F->getEntryBlock().begin());
}
// We cannot demote invoke instructions to the stack if their normal edge
// is critical. Therefore, split the critical edge and create a basic block
// into which the store can be inserted.
if (InvokeInst *II = dyn_cast<InvokeInst>(&I)) {
if (!II->getNormalDest()->getSinglePredecessor()) {
unsigned SuccNum = GetSuccessorNumber(II->getParent(), II->getNormalDest());
assert(isCriticalEdge(II, SuccNum) && "Expected a critical edge!");
BasicBlock *BB = SplitCriticalEdge(II, SuccNum);
assert(BB && "Unable to split critical edge.");
(void)BB;
}
}
// Change all of the users of the instruction to read from the stack slot.
while (!I.use_empty()) {
Instruction *U = cast<Instruction>(I.user_back());
if (PHINode *PN = dyn_cast<PHINode>(U)) {
// If this is a PHI node, we can't insert a load of the value before the
// use. Instead insert the load in the predecessor block corresponding
// to the incoming value.
//
// Note that if there are multiple edges from a basic block to this PHI
// node that we cannot have multiple loads. The problem is that the
// resulting PHI node will have multiple values (from each load) coming in
// from the same block, which is illegal SSA form. For this reason, we
// keep track of and reuse loads we insert.
DenseMap<BasicBlock*, Value*> Loads;
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
if (PN->getIncomingValue(i) == &I) {
Value *&V = Loads[PN->getIncomingBlock(i)];
if (!V) {
// Insert the load into the predecessor block
V = new LoadInst(Slot, I.getName()+".reload", VolatileLoads,
PN->getIncomingBlock(i)->getTerminator());
}
PN->setIncomingValue(i, V);
}
} else {
// If this is a normal instruction, just insert a load.
Value *V = new LoadInst(Slot, I.getName()+".reload", VolatileLoads, U);
U->replaceUsesOfWith(&I, V);
}
}
// Insert stores of the computed value into the stack slot. We have to be
// careful if I is an invoke instruction, because we can't insert the store
// AFTER the terminator instruction.
BasicBlock::iterator InsertPt;
if (!isa<TerminatorInst>(I)) {
InsertPt = &I;
++InsertPt;
for (; isa<PHINode>(InsertPt) || isa<LandingPadInst>(InsertPt); ++InsertPt)
/* empty */; // Don't insert before PHI nodes or landingpad instrs.
} else {
InvokeInst &II = cast<InvokeInst>(I);
InsertPt = II.getNormalDest()->getFirstInsertionPt();
}
new StoreInst(&I, Slot, InsertPt);
return Slot;
}
/// DemotePHIToStack - This function takes a virtual register computed by a PHI
/// node and replaces it with a slot in the stack frame allocated via alloca.
/// The PHI node is deleted. It returns the pointer to the alloca inserted.
AllocaInst *llvm::DemotePHIToStack(PHINode *P, Instruction *AllocaPoint) {
if (P->use_empty()) {
P->eraseFromParent();
return nullptr;
}
// Create a stack slot to hold the value.
AllocaInst *Slot;
if (AllocaPoint) {
Slot = new AllocaInst(P->getType(), nullptr,
P->getName()+".reg2mem", AllocaPoint);
} else {
Function *F = P->getParent()->getParent();
Slot = new AllocaInst(P->getType(), nullptr, P->getName()+".reg2mem",
F->getEntryBlock().begin());
}
// Iterate over each operand inserting a store in each predecessor.
for (unsigned i = 0, e = P->getNumIncomingValues(); i < e; ++i) {
if (InvokeInst *II = dyn_cast<InvokeInst>(P->getIncomingValue(i))) {
assert(II->getParent() != P->getIncomingBlock(i) &&
"Invoke edge not supported yet"); (void)II;
}
new StoreInst(P->getIncomingValue(i), Slot,
P->getIncomingBlock(i)->getTerminator());
}
// Insert a load in place of the PHI and replace all uses.
BasicBlock::iterator InsertPt = P;
for (; isa<PHINode>(InsertPt) || isa<LandingPadInst>(InsertPt); ++InsertPt)
/* empty */; // Don't insert before PHI nodes or landingpad instrs.
Value *V = new LoadInst(Slot, P->getName()+".reload", InsertPt);
P->replaceAllUsesWith(V);
// Delete PHI.
P->eraseFromParent();
return Slot;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/Mem2Reg.cpp | //===- Mem2Reg.cpp - The -mem2reg pass, a wrapper around the Utils lib ----===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This pass is a simple pass wrapper around the PromoteMemToReg function call
// exposed by the Utils library.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Scalar.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instructions.h"
#include "llvm/Transforms/Utils/PromoteMemToReg.h"
#include "llvm/Transforms/Utils/UnifyFunctionExitNodes.h"
using namespace llvm;
#define DEBUG_TYPE "mem2reg"
STATISTIC(NumPromoted, "Number of alloca's promoted");
namespace {
struct PromotePass : public FunctionPass {
static char ID; // Pass identification, replacement for typeid
PromotePass() : FunctionPass(ID) {
initializePromotePassPass(*PassRegistry::getPassRegistry());
}
// runOnFunction - To run this pass, first we calculate the alloca
// instructions that are safe for promotion, then we promote each one.
//
bool runOnFunction(Function &F) override;
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addRequired<AssumptionCacheTracker>();
AU.addRequired<DominatorTreeWrapperPass>();
AU.setPreservesCFG();
// This is a cluster of orthogonal Transforms
AU.addPreserved<UnifyFunctionExitNodes>();
AU.addPreservedID(LowerSwitchID);
AU.addPreservedID(LowerInvokePassID);
}
};
} // end of anonymous namespace
char PromotePass::ID = 0;
INITIALIZE_PASS_BEGIN(PromotePass, "mem2reg", "Promote Memory to Register",
false, false)
INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_END(PromotePass, "mem2reg", "Promote Memory to Register",
false, false)
bool PromotePass::runOnFunction(Function &F) {
std::vector<AllocaInst*> Allocas;
BasicBlock &BB = F.getEntryBlock(); // Get the entry node for the function
bool Changed = false;
DominatorTree &DT = getAnalysis<DominatorTreeWrapperPass>().getDomTree();
AssumptionCache &AC =
getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
while (1) {
Allocas.clear();
// Find allocas that are safe to promote, by looking at all instructions in
// the entry node
for (BasicBlock::iterator I = BB.begin(), E = --BB.end(); I != E; ++I)
if (AllocaInst *AI = dyn_cast<AllocaInst>(I)) // Is it an alloca?
if (isAllocaPromotable(AI))
Allocas.push_back(AI);
if (Allocas.empty()) break;
PromoteMemToReg(Allocas, DT, nullptr, &AC);
NumPromoted += Allocas.size();
Changed = true;
}
return Changed;
}
// createPromoteMemoryToRegister - Provide an entry point to create this pass.
//
FunctionPass *llvm::createPromoteMemoryToRegisterPass() {
return new PromotePass();
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/Utils.cpp | //===-- Utils.cpp - TransformUtils Infrastructure -------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the common initialization infrastructure for the
// TransformUtils library.
//
//===----------------------------------------------------------------------===//
#include "llvm/InitializePasses.h"
#include "llvm-c/Initialization.h"
#include "llvm/PassRegistry.h"
using namespace llvm;
/// initializeTransformUtils - Initialize all passes in the TransformUtils
/// library.
void llvm::initializeTransformUtils(PassRegistry &Registry) {
initializeAddDiscriminatorsPass(Registry);
initializeBreakCriticalEdgesPass(Registry);
initializeInstNamerPass(Registry);
initializeLCSSAPass(Registry);
initializeLoopSimplifyPass(Registry);
initializeLowerInvokePass(Registry);
initializeLowerSwitchPass(Registry);
initializePromotePassPass(Registry);
initializeUnifyFunctionExitNodesPass(Registry);
initializeInstSimplifierPass(Registry);
initializeMetaRenamerPass(Registry);
}
/// LLVMInitializeTransformUtils - C binding for initializeTransformUtilsPasses.
void LLVMInitializeTransformUtils(LLVMPassRegistryRef R) {
initializeTransformUtils(*unwrap(R));
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/GlobalStatus.cpp | //===-- GlobalStatus.cpp - Compute status info for globals -----------------==//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/Transforms/Utils/GlobalStatus.h"
using namespace llvm;
/// Return the stronger of the two ordering. If the two orderings are acquire
/// and release, then return AcquireRelease.
///
static AtomicOrdering strongerOrdering(AtomicOrdering X, AtomicOrdering Y) {
if (X == Acquire && Y == Release)
return AcquireRelease;
if (Y == Acquire && X == Release)
return AcquireRelease;
return (AtomicOrdering)std::max(X, Y);
}
/// It is safe to destroy a constant iff it is only used by constants itself.
/// Note that constants cannot be cyclic, so this test is pretty easy to
/// implement recursively.
///
bool llvm::isSafeToDestroyConstant(const Constant *C) {
if (isa<GlobalValue>(C))
return false;
if (isa<ConstantInt>(C) || isa<ConstantFP>(C))
return false;
for (const User *U : C->users())
if (const Constant *CU = dyn_cast<Constant>(U)) {
if (!isSafeToDestroyConstant(CU))
return false;
} else
return false;
return true;
}
static bool analyzeGlobalAux(const Value *V, GlobalStatus &GS,
SmallPtrSetImpl<const PHINode *> &PhiUsers) {
for (const Use &U : V->uses()) {
const User *UR = U.getUser();
if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(UR)) {
GS.HasNonInstructionUser = true;
// If the result of the constantexpr isn't pointer type, then we won't
// know to expect it in various places. Just reject early.
if (!isa<PointerType>(CE->getType()))
return true;
if (analyzeGlobalAux(CE, GS, PhiUsers))
return true;
} else if (const Instruction *I = dyn_cast<Instruction>(UR)) {
if (!GS.HasMultipleAccessingFunctions) {
const Function *F = I->getParent()->getParent();
if (!GS.AccessingFunction)
GS.AccessingFunction = F;
else if (GS.AccessingFunction != F)
GS.HasMultipleAccessingFunctions = true;
}
if (const LoadInst *LI = dyn_cast<LoadInst>(I)) {
GS.IsLoaded = true;
// Don't hack on volatile loads.
if (LI->isVolatile())
return true;
GS.Ordering = strongerOrdering(GS.Ordering, LI->getOrdering());
} else if (const StoreInst *SI = dyn_cast<StoreInst>(I)) {
// Don't allow a store OF the address, only stores TO the address.
if (SI->getOperand(0) == V)
return true;
// Don't hack on volatile stores.
if (SI->isVolatile())
return true;
GS.Ordering = strongerOrdering(GS.Ordering, SI->getOrdering());
// If this is a direct store to the global (i.e., the global is a scalar
// value, not an aggregate), keep more specific information about
// stores.
if (GS.StoredType != GlobalStatus::Stored) {
if (const GlobalVariable *GV =
dyn_cast<GlobalVariable>(SI->getOperand(1))) {
Value *StoredVal = SI->getOperand(0);
if (Constant *C = dyn_cast<Constant>(StoredVal)) {
if (C->isThreadDependent()) {
// The stored value changes between threads; don't track it.
return true;
}
}
if (StoredVal == GV->getInitializer()) {
if (GS.StoredType < GlobalStatus::InitializerStored)
GS.StoredType = GlobalStatus::InitializerStored;
} else if (isa<LoadInst>(StoredVal) &&
cast<LoadInst>(StoredVal)->getOperand(0) == GV) {
if (GS.StoredType < GlobalStatus::InitializerStored)
GS.StoredType = GlobalStatus::InitializerStored;
} else if (GS.StoredType < GlobalStatus::StoredOnce) {
GS.StoredType = GlobalStatus::StoredOnce;
GS.StoredOnceValue = StoredVal;
} else if (GS.StoredType == GlobalStatus::StoredOnce &&
GS.StoredOnceValue == StoredVal) {
// noop.
} else {
GS.StoredType = GlobalStatus::Stored;
}
} else {
GS.StoredType = GlobalStatus::Stored;
}
}
} else if (isa<BitCastInst>(I)) {
if (analyzeGlobalAux(I, GS, PhiUsers))
return true;
} else if (isa<GetElementPtrInst>(I)) {
if (analyzeGlobalAux(I, GS, PhiUsers))
return true;
} else if (isa<SelectInst>(I)) {
if (analyzeGlobalAux(I, GS, PhiUsers))
return true;
} else if (const PHINode *PN = dyn_cast<PHINode>(I)) {
// PHI nodes we can check just like select or GEP instructions, but we
// have to be careful about infinite recursion.
if (PhiUsers.insert(PN).second) // Not already visited.
if (analyzeGlobalAux(I, GS, PhiUsers))
return true;
} else if (isa<CmpInst>(I)) {
GS.IsCompared = true;
} else if (const MemTransferInst *MTI = dyn_cast<MemTransferInst>(I)) {
if (MTI->isVolatile())
return true;
if (MTI->getArgOperand(0) == V)
GS.StoredType = GlobalStatus::Stored;
if (MTI->getArgOperand(1) == V)
GS.IsLoaded = true;
} else if (const MemSetInst *MSI = dyn_cast<MemSetInst>(I)) {
assert(MSI->getArgOperand(0) == V && "Memset only takes one pointer!");
if (MSI->isVolatile())
return true;
GS.StoredType = GlobalStatus::Stored;
} else if (auto C = ImmutableCallSite(I)) {
if (!C.isCallee(&U))
return true;
GS.IsLoaded = true;
} else {
return true; // Any other non-load instruction might take address!
}
} else if (const Constant *C = dyn_cast<Constant>(UR)) {
GS.HasNonInstructionUser = true;
// We might have a dead and dangling constant hanging off of here.
if (!isSafeToDestroyConstant(C))
return true;
} else {
GS.HasNonInstructionUser = true;
// Otherwise must be some other user.
return true;
}
}
return false;
}
bool GlobalStatus::analyzeGlobal(const Value *V, GlobalStatus &GS) {
SmallPtrSet<const PHINode *, 16> PhiUsers;
return analyzeGlobalAux(V, GS, PhiUsers);
}
GlobalStatus::GlobalStatus()
: IsCompared(false), IsLoaded(false), StoredType(NotStored),
StoredOnceValue(nullptr), AccessingFunction(nullptr),
HasMultipleAccessingFunctions(false), HasNonInstructionUser(false),
Ordering(NotAtomic) {}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/CtorUtils.cpp | //===- CtorUtils.cpp - Helpers for working with global_ctors ----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines functions that are used to process llvm.global_ctors.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/CtorUtils.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#define DEBUG_TYPE "ctor_utils"
namespace llvm {
namespace {
/// Given a specified llvm.global_ctors list, remove the listed elements.
void removeGlobalCtors(GlobalVariable *GCL, const BitVector &CtorsToRemove) {
// Filter out the initializer elements to remove.
ConstantArray *OldCA = cast<ConstantArray>(GCL->getInitializer());
SmallVector<Constant *, 10> CAList;
for (unsigned I = 0, E = OldCA->getNumOperands(); I < E; ++I)
if (!CtorsToRemove.test(I))
CAList.push_back(OldCA->getOperand(I));
// Create the new array initializer.
ArrayType *ATy =
ArrayType::get(OldCA->getType()->getElementType(), CAList.size());
Constant *CA = ConstantArray::get(ATy, CAList);
// If we didn't change the number of elements, don't create a new GV.
if (CA->getType() == OldCA->getType()) {
GCL->setInitializer(CA);
return;
}
// Create the new global and insert it next to the existing list.
GlobalVariable *NGV =
new GlobalVariable(CA->getType(), GCL->isConstant(), GCL->getLinkage(),
CA, "", GCL->getThreadLocalMode());
GCL->getParent()->getGlobalList().insert(GCL, NGV);
NGV->takeName(GCL);
// Nuke the old list, replacing any uses with the new one.
if (!GCL->use_empty()) {
Constant *V = NGV;
if (V->getType() != GCL->getType())
V = ConstantExpr::getBitCast(V, GCL->getType());
GCL->replaceAllUsesWith(V);
}
GCL->eraseFromParent();
}
/// Given a llvm.global_ctors list that we can understand,
/// return a list of the functions and null terminator as a vector.
std::vector<Function *> parseGlobalCtors(GlobalVariable *GV) {
if (GV->getInitializer()->isNullValue())
return std::vector<Function *>();
ConstantArray *CA = cast<ConstantArray>(GV->getInitializer());
std::vector<Function *> Result;
Result.reserve(CA->getNumOperands());
for (User::op_iterator i = CA->op_begin(), e = CA->op_end(); i != e; ++i) {
ConstantStruct *CS = cast<ConstantStruct>(*i);
Result.push_back(dyn_cast<Function>(CS->getOperand(1)));
}
return Result;
}
/// Find the llvm.global_ctors list, verifying that all initializers have an
/// init priority of 65535.
GlobalVariable *findGlobalCtors(Module &M) {
GlobalVariable *GV = M.getGlobalVariable("llvm.global_ctors");
if (!GV)
return nullptr;
// Verify that the initializer is simple enough for us to handle. We are
// only allowed to optimize the initializer if it is unique.
if (!GV->hasUniqueInitializer())
return nullptr;
if (isa<ConstantAggregateZero>(GV->getInitializer()))
return GV;
ConstantArray *CA = cast<ConstantArray>(GV->getInitializer());
for (User::op_iterator i = CA->op_begin(), e = CA->op_end(); i != e; ++i) {
if (isa<ConstantAggregateZero>(*i))
continue;
ConstantStruct *CS = cast<ConstantStruct>(*i);
if (isa<ConstantPointerNull>(CS->getOperand(1)))
continue;
// Must have a function or null ptr.
if (!isa<Function>(CS->getOperand(1)))
return nullptr;
// Init priority must be standard.
ConstantInt *CI = cast<ConstantInt>(CS->getOperand(0));
if (CI->getZExtValue() != 65535)
return nullptr;
}
return GV;
}
} // namespace
/// Call "ShouldRemove" for every entry in M's global_ctor list and remove the
/// entries for which it returns true. Return true if anything changed.
bool optimizeGlobalCtorsList(Module &M,
function_ref<bool(Function *)> ShouldRemove) {
GlobalVariable *GlobalCtors = findGlobalCtors(M);
if (!GlobalCtors)
return false;
std::vector<Function *> Ctors = parseGlobalCtors(GlobalCtors);
if (Ctors.empty())
return false;
bool MadeChange = false;
// Loop over global ctors, optimizing them when we can.
unsigned NumCtors = Ctors.size();
BitVector CtorsToRemove(NumCtors);
for (unsigned i = 0; i != Ctors.size() && NumCtors > 0; ++i) {
Function *F = Ctors[i];
// Found a null terminator in the middle of the list, prune off the rest of
// the list.
if (!F)
continue;
DEBUG(dbgs() << "Optimizing Global Constructor: " << *F << "\n");
// We cannot simplify external ctor functions.
if (F->empty())
continue;
// If we can evaluate the ctor at compile time, do.
if (ShouldRemove(F)) {
Ctors[i] = nullptr;
CtorsToRemove.set(i);
NumCtors--;
MadeChange = true;
continue;
}
}
if (!MadeChange)
return false;
removeGlobalCtors(GlobalCtors, CtorsToRemove);
return true;
}
} // End llvm namespace
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/LoopUnroll.cpp | //===-- UnrollLoop.cpp - Loop unrolling utilities -------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements some loop unrolling utilities. It does not define any
// actual pass or policy, but provides a single function to perform loop
// unrolling.
//
// The process of unrolling can produce extraneous basic blocks linked with
// unconditional branches. This will be corrected in the future.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/UnrollLoop.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/LoopIterator.h"
#include "llvm/Analysis/LoopPass.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DiagnosticInfo.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Cloning.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/LoopUtils.h"
#include "llvm/Transforms/Utils/SimplifyIndVar.h"
using namespace llvm;
#define DEBUG_TYPE "loop-unroll"
// TODO: Should these be here or in LoopUnroll?
STATISTIC(NumCompletelyUnrolled, "Number of loops completely unrolled");
STATISTIC(NumUnrolled, "Number of loops unrolled (completely or otherwise)");
/// RemapInstruction - Convert the instruction operands from referencing the
/// current values into those specified by VMap.
static inline void RemapInstruction(Instruction *I,
ValueToValueMapTy &VMap) {
for (unsigned op = 0, E = I->getNumOperands(); op != E; ++op) {
Value *Op = I->getOperand(op);
ValueToValueMapTy::iterator It = VMap.find(Op);
if (It != VMap.end())
I->setOperand(op, It->second);
}
if (PHINode *PN = dyn_cast<PHINode>(I)) {
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
ValueToValueMapTy::iterator It = VMap.find(PN->getIncomingBlock(i));
if (It != VMap.end())
PN->setIncomingBlock(i, cast<BasicBlock>(It->second));
}
}
}
/// FoldBlockIntoPredecessor - Folds a basic block into its predecessor if it
/// only has one predecessor, and that predecessor only has one successor.
/// The LoopInfo Analysis that is passed will be kept consistent. If folding is
/// successful references to the containing loop must be removed from
/// ScalarEvolution by calling ScalarEvolution::forgetLoop because SE may have
/// references to the eliminated BB. The argument ForgottenLoops contains a set
/// of loops that have already been forgotten to prevent redundant, expensive
/// calls to ScalarEvolution::forgetLoop. Returns the new combined block.
static BasicBlock *
FoldBlockIntoPredecessor(BasicBlock *BB, LoopInfo* LI, LPPassManager *LPM,
SmallPtrSetImpl<Loop *> &ForgottenLoops) {
// Merge basic blocks into their predecessor if there is only one distinct
// pred, and if there is only one distinct successor of the predecessor, and
// if there are no PHI nodes.
BasicBlock *OnlyPred = BB->getSinglePredecessor();
if (!OnlyPred) return nullptr;
if (OnlyPred->getTerminator()->getNumSuccessors() != 1)
return nullptr;
DEBUG(dbgs() << "Merging: " << *BB << "into: " << *OnlyPred);
// Resolve any PHI nodes at the start of the block. They are all
// guaranteed to have exactly one entry if they exist, unless there are
// multiple duplicate (but guaranteed to be equal) entries for the
// incoming edges. This occurs when there are multiple edges from
// OnlyPred to OnlySucc.
FoldSingleEntryPHINodes(BB);
// Delete the unconditional branch from the predecessor...
OnlyPred->getInstList().pop_back();
// Make all PHI nodes that referred to BB now refer to Pred as their
// source...
BB->replaceAllUsesWith(OnlyPred);
// Move all definitions in the successor to the predecessor...
OnlyPred->getInstList().splice(OnlyPred->end(), BB->getInstList());
// OldName will be valid until erased.
StringRef OldName = BB->getName();
// Erase basic block from the function...
// ScalarEvolution holds references to loop exit blocks.
if (LPM) {
if (ScalarEvolution *SE = LPM->getAnalysisIfAvailable<ScalarEvolution>()) {
if (Loop *L = LI->getLoopFor(BB)) {
if (ForgottenLoops.insert(L).second)
SE->forgetLoop(L);
}
}
}
LI->removeBlock(BB);
// Inherit predecessor's name if it exists...
if (!OldName.empty() && !OnlyPred->hasName())
OnlyPred->setName(OldName);
BB->eraseFromParent();
return OnlyPred;
}
/// Unroll the given loop by Count. The loop must be in LCSSA form. Returns true
/// if unrolling was successful, or false if the loop was unmodified. Unrolling
/// can only fail when the loop's latch block is not terminated by a conditional
/// branch instruction. However, if the trip count (and multiple) are not known,
/// loop unrolling will mostly produce more code that is no faster.
///
/// TripCount is generally defined as the number of times the loop header
/// executes. UnrollLoop relaxes the definition to permit early exits: here
/// TripCount is the iteration on which control exits LatchBlock if no early
/// exits were taken. Note that UnrollLoop assumes that the loop counter test
/// terminates LatchBlock in order to remove unnecesssary instances of the
/// test. In other words, control may exit the loop prior to TripCount
/// iterations via an early branch, but control may not exit the loop from the
/// LatchBlock's terminator prior to TripCount iterations.
///
/// Similarly, TripMultiple divides the number of times that the LatchBlock may
/// execute without exiting the loop.
///
/// If AllowRuntime is true then UnrollLoop will consider unrolling loops that
/// have a runtime (i.e. not compile time constant) trip count. Unrolling these
/// loops require a unroll "prologue" that runs "RuntimeTripCount % Count"
/// iterations before branching into the unrolled loop. UnrollLoop will not
/// runtime-unroll the loop if computing RuntimeTripCount will be expensive and
/// AllowExpensiveTripCount is false.
///
/// The LoopInfo Analysis that is passed will be kept consistent.
///
/// If a LoopPassManager is passed in, and the loop is fully removed, it will be
/// removed from the LoopPassManager as well. LPM can also be NULL.
///
/// This utility preserves LoopInfo. If DominatorTree or ScalarEvolution are
/// available from the Pass it must also preserve those analyses.
bool llvm::UnrollLoop(Loop *L, unsigned Count, unsigned TripCount,
bool AllowRuntime, bool AllowExpensiveTripCount,
unsigned TripMultiple, LoopInfo *LI, Pass *PP,
LPPassManager *LPM, AssumptionCache *AC) {
BasicBlock *Preheader = L->getLoopPreheader();
if (!Preheader) {
DEBUG(dbgs() << " Can't unroll; loop preheader-insertion failed.\n");
return false;
}
BasicBlock *LatchBlock = L->getLoopLatch();
if (!LatchBlock) {
DEBUG(dbgs() << " Can't unroll; loop exit-block-insertion failed.\n");
return false;
}
// Loops with indirectbr cannot be cloned.
if (!L->isSafeToClone()) {
DEBUG(dbgs() << " Can't unroll; Loop body cannot be cloned.\n");
return false;
}
BasicBlock *Header = L->getHeader();
BranchInst *BI = dyn_cast<BranchInst>(LatchBlock->getTerminator());
if (!BI || BI->isUnconditional()) {
// The loop-rotate pass can be helpful to avoid this in many cases.
DEBUG(dbgs() <<
" Can't unroll; loop not terminated by a conditional branch.\n");
return false;
}
if (Header->hasAddressTaken()) {
// The loop-rotate pass can be helpful to avoid this in many cases.
DEBUG(dbgs() <<
" Won't unroll loop: address of header block is taken.\n");
return false;
}
if (TripCount != 0)
DEBUG(dbgs() << " Trip Count = " << TripCount << "\n");
if (TripMultiple != 1)
DEBUG(dbgs() << " Trip Multiple = " << TripMultiple << "\n");
// Effectively "DCE" unrolled iterations that are beyond the tripcount
// and will never be executed.
if (TripCount != 0 && Count > TripCount)
Count = TripCount;
// Don't enter the unroll code if there is nothing to do. This way we don't
// need to support "partial unrolling by 1".
if (TripCount == 0 && Count < 2)
return false;
assert(Count > 0);
assert(TripMultiple > 0);
assert(TripCount == 0 || TripCount % TripMultiple == 0);
// Are we eliminating the loop control altogether?
bool CompletelyUnroll = Count == TripCount;
// We assume a run-time trip count if the compiler cannot
// figure out the loop trip count and the unroll-runtime
// flag is specified.
bool RuntimeTripCount = (TripCount == 0 && Count > 0 && AllowRuntime);
if (RuntimeTripCount &&
!UnrollRuntimeLoopProlog(L, Count, AllowExpensiveTripCount, LI, LPM))
return false;
// Notify ScalarEvolution that the loop will be substantially changed,
// if not outright eliminated.
ScalarEvolution *SE =
PP ? PP->getAnalysisIfAvailable<ScalarEvolution>() : nullptr;
if (SE)
SE->forgetLoop(L);
// If we know the trip count, we know the multiple...
unsigned BreakoutTrip = 0;
if (TripCount != 0) {
BreakoutTrip = TripCount % Count;
TripMultiple = 0;
} else {
// Figure out what multiple to use.
BreakoutTrip = TripMultiple =
(unsigned)GreatestCommonDivisor64(Count, TripMultiple);
}
// Report the unrolling decision.
DebugLoc LoopLoc = L->getStartLoc();
Function *F = Header->getParent();
LLVMContext &Ctx = F->getContext();
if (CompletelyUnroll) {
DEBUG(dbgs() << "COMPLETELY UNROLLING loop %" << Header->getName()
<< " with trip count " << TripCount << "!\n");
emitOptimizationRemark(Ctx, DEBUG_TYPE, *F, LoopLoc,
Twine("completely unrolled loop with ") +
Twine(TripCount) + " iterations");
} else {
auto EmitDiag = [&](const Twine &T) {
emitOptimizationRemark(Ctx, DEBUG_TYPE, *F, LoopLoc,
"unrolled loop by a factor of " + Twine(Count) +
T);
};
DEBUG(dbgs() << "UNROLLING loop %" << Header->getName()
<< " by " << Count);
if (TripMultiple == 0 || BreakoutTrip != TripMultiple) {
DEBUG(dbgs() << " with a breakout at trip " << BreakoutTrip);
EmitDiag(" with a breakout at trip " + Twine(BreakoutTrip));
} else if (TripMultiple != 1) {
DEBUG(dbgs() << " with " << TripMultiple << " trips per branch");
EmitDiag(" with " + Twine(TripMultiple) + " trips per branch");
} else if (RuntimeTripCount) {
DEBUG(dbgs() << " with run-time trip count");
EmitDiag(" with run-time trip count");
}
DEBUG(dbgs() << "!\n");
}
bool ContinueOnTrue = L->contains(BI->getSuccessor(0));
BasicBlock *LoopExit = BI->getSuccessor(ContinueOnTrue);
// For the first iteration of the loop, we should use the precloned values for
// PHI nodes. Insert associations now.
ValueToValueMapTy LastValueMap;
std::vector<PHINode*> OrigPHINode;
for (BasicBlock::iterator I = Header->begin(); isa<PHINode>(I); ++I) {
OrigPHINode.push_back(cast<PHINode>(I));
}
std::vector<BasicBlock*> Headers;
std::vector<BasicBlock*> Latches;
Headers.push_back(Header);
Latches.push_back(LatchBlock);
// The current on-the-fly SSA update requires blocks to be processed in
// reverse postorder so that LastValueMap contains the correct value at each
// exit.
LoopBlocksDFS DFS(L);
DFS.perform(LI);
// Stash the DFS iterators before adding blocks to the loop.
LoopBlocksDFS::RPOIterator BlockBegin = DFS.beginRPO();
LoopBlocksDFS::RPOIterator BlockEnd = DFS.endRPO();
for (unsigned It = 1; It != Count; ++It) {
std::vector<BasicBlock*> NewBlocks;
SmallDenseMap<const Loop *, Loop *, 4> NewLoops;
NewLoops[L] = L;
for (LoopBlocksDFS::RPOIterator BB = BlockBegin; BB != BlockEnd; ++BB) {
ValueToValueMapTy VMap;
BasicBlock *New = CloneBasicBlock(*BB, VMap, "." + Twine(It));
Header->getParent()->getBasicBlockList().push_back(New);
// Tell LI about New.
if (*BB == Header) {
assert(LI->getLoopFor(*BB) == L && "Header should not be in a sub-loop");
L->addBasicBlockToLoop(New, *LI);
} else {
// Figure out which loop New is in.
const Loop *OldLoop = LI->getLoopFor(*BB);
assert(OldLoop && "Should (at least) be in the loop being unrolled!");
Loop *&NewLoop = NewLoops[OldLoop];
if (!NewLoop) {
// Found a new sub-loop.
assert(*BB == OldLoop->getHeader() &&
"Header should be first in RPO");
Loop *NewLoopParent = NewLoops.lookup(OldLoop->getParentLoop());
assert(NewLoopParent &&
"Expected parent loop before sub-loop in RPO");
NewLoop = new Loop;
NewLoopParent->addChildLoop(NewLoop);
// Forget the old loop, since its inputs may have changed.
if (SE)
SE->forgetLoop(OldLoop);
}
NewLoop->addBasicBlockToLoop(New, *LI);
}
if (*BB == Header)
// Loop over all of the PHI nodes in the block, changing them to use
// the incoming values from the previous block.
for (unsigned i = 0, e = OrigPHINode.size(); i != e; ++i) {
PHINode *NewPHI = cast<PHINode>(VMap[OrigPHINode[i]]);
Value *InVal = NewPHI->getIncomingValueForBlock(LatchBlock);
if (Instruction *InValI = dyn_cast<Instruction>(InVal))
if (It > 1 && L->contains(InValI))
InVal = LastValueMap[InValI];
VMap[OrigPHINode[i]] = InVal;
New->getInstList().erase(NewPHI);
}
// Update our running map of newest clones
LastValueMap[*BB] = New;
for (ValueToValueMapTy::iterator VI = VMap.begin(), VE = VMap.end();
VI != VE; ++VI)
LastValueMap[VI->first] = VI->second;
// Add phi entries for newly created values to all exit blocks.
for (succ_iterator SI = succ_begin(*BB), SE = succ_end(*BB);
SI != SE; ++SI) {
if (L->contains(*SI))
continue;
for (BasicBlock::iterator BBI = (*SI)->begin();
PHINode *phi = dyn_cast<PHINode>(BBI); ++BBI) {
Value *Incoming = phi->getIncomingValueForBlock(*BB);
ValueToValueMapTy::iterator It = LastValueMap.find(Incoming);
if (It != LastValueMap.end())
Incoming = It->second;
phi->addIncoming(Incoming, New);
}
}
// Keep track of new headers and latches as we create them, so that
// we can insert the proper branches later.
if (*BB == Header)
Headers.push_back(New);
if (*BB == LatchBlock)
Latches.push_back(New);
NewBlocks.push_back(New);
}
// Remap all instructions in the most recent iteration
for (unsigned i = 0; i < NewBlocks.size(); ++i)
for (BasicBlock::iterator I = NewBlocks[i]->begin(),
E = NewBlocks[i]->end(); I != E; ++I)
::RemapInstruction(I, LastValueMap);
}
// Loop over the PHI nodes in the original block, setting incoming values.
for (unsigned i = 0, e = OrigPHINode.size(); i != e; ++i) {
PHINode *PN = OrigPHINode[i];
if (CompletelyUnroll) {
PN->replaceAllUsesWith(PN->getIncomingValueForBlock(Preheader));
Header->getInstList().erase(PN);
}
else if (Count > 1) {
Value *InVal = PN->removeIncomingValue(LatchBlock, false);
// If this value was defined in the loop, take the value defined by the
// last iteration of the loop.
if (Instruction *InValI = dyn_cast<Instruction>(InVal)) {
if (L->contains(InValI))
InVal = LastValueMap[InVal];
}
assert(Latches.back() == LastValueMap[LatchBlock] && "bad last latch");
PN->addIncoming(InVal, Latches.back());
}
}
// Now that all the basic blocks for the unrolled iterations are in place,
// set up the branches to connect them.
for (unsigned i = 0, e = Latches.size(); i != e; ++i) {
// The original branch was replicated in each unrolled iteration.
BranchInst *Term = cast<BranchInst>(Latches[i]->getTerminator());
// The branch destination.
unsigned j = (i + 1) % e;
BasicBlock *Dest = Headers[j];
bool NeedConditional = true;
if (RuntimeTripCount && j != 0) {
NeedConditional = false;
}
// For a complete unroll, make the last iteration end with a branch
// to the exit block.
if (CompletelyUnroll && j == 0) {
Dest = LoopExit;
NeedConditional = false;
}
// If we know the trip count or a multiple of it, we can safely use an
// unconditional branch for some iterations.
if (j != BreakoutTrip && (TripMultiple == 0 || j % TripMultiple != 0)) {
NeedConditional = false;
}
if (NeedConditional) {
// Update the conditional branch's successor for the following
// iteration.
Term->setSuccessor(!ContinueOnTrue, Dest);
} else {
// Remove phi operands at this loop exit
if (Dest != LoopExit) {
BasicBlock *BB = Latches[i];
for (succ_iterator SI = succ_begin(BB), SE = succ_end(BB);
SI != SE; ++SI) {
if (*SI == Headers[i])
continue;
for (BasicBlock::iterator BBI = (*SI)->begin();
PHINode *Phi = dyn_cast<PHINode>(BBI); ++BBI) {
Phi->removeIncomingValue(BB, false);
}
}
}
// Replace the conditional branch with an unconditional one.
BranchInst::Create(Dest, Term);
Term->eraseFromParent();
}
}
// Merge adjacent basic blocks, if possible.
SmallPtrSet<Loop *, 4> ForgottenLoops;
for (unsigned i = 0, e = Latches.size(); i != e; ++i) {
BranchInst *Term = cast<BranchInst>(Latches[i]->getTerminator());
if (Term->isUnconditional()) {
BasicBlock *Dest = Term->getSuccessor(0);
if (BasicBlock *Fold = FoldBlockIntoPredecessor(Dest, LI, LPM,
ForgottenLoops))
std::replace(Latches.begin(), Latches.end(), Dest, Fold);
}
}
// FIXME: We could register any cloned assumptions instead of clearing the
// whole function's cache.
AC->clear();
DominatorTree *DT = nullptr;
if (PP) {
// FIXME: Reconstruct dom info, because it is not preserved properly.
// Incrementally updating domtree after loop unrolling would be easy.
if (DominatorTreeWrapperPass *DTWP =
PP->getAnalysisIfAvailable<DominatorTreeWrapperPass>()) {
DT = &DTWP->getDomTree();
DT->recalculate(*L->getHeader()->getParent());
}
// Simplify any new induction variables in the partially unrolled loop.
if (SE && !CompletelyUnroll) {
SmallVector<WeakTrackingVH, 16> DeadInsts;
simplifyLoopIVs(L, SE, LPM, DeadInsts);
// Aggressively clean up dead instructions that simplifyLoopIVs already
// identified. Any remaining should be cleaned up below.
while (!DeadInsts.empty())
if (Instruction *Inst =
dyn_cast_or_null<Instruction>(&*DeadInsts.pop_back_val()))
RecursivelyDeleteTriviallyDeadInstructions(Inst);
}
}
// At this point, the code is well formed. We now do a quick sweep over the
// inserted code, doing constant propagation and dead code elimination as we
// go.
const DataLayout &DL = Header->getModule()->getDataLayout();
const std::vector<BasicBlock*> &NewLoopBlocks = L->getBlocks();
for (std::vector<BasicBlock*>::const_iterator BB = NewLoopBlocks.begin(),
BBE = NewLoopBlocks.end(); BB != BBE; ++BB)
for (BasicBlock::iterator I = (*BB)->begin(), E = (*BB)->end(); I != E; ) {
Instruction *Inst = I++;
if (isInstructionTriviallyDead(Inst))
(*BB)->getInstList().erase(Inst);
else if (Value *V = SimplifyInstruction(Inst, DL))
if (LI->replacementPreservesLCSSAForm(Inst, V)) {
Inst->replaceAllUsesWith(V);
(*BB)->getInstList().erase(Inst);
}
}
NumCompletelyUnrolled += CompletelyUnroll;
++NumUnrolled;
Loop *OuterL = L->getParentLoop();
// Remove the loop from the LoopPassManager if it's completely removed.
if (CompletelyUnroll && LPM != nullptr)
LPM->deleteLoopFromQueue(L);
// If we have a pass and a DominatorTree we should re-simplify impacted loops
// to ensure subsequent analyses can rely on this form. We want to simplify
// at least one layer outside of the loop that was unrolled so that any
// changes to the parent loop exposed by the unrolling are considered.
if (PP && DT) {
if (!OuterL && !CompletelyUnroll)
OuterL = L;
if (OuterL) {
simplifyLoop(OuterL, DT, LI, PP, /*AliasAnalysis*/ nullptr, SE, AC);
// LCSSA must be performed on the outermost affected loop. The unrolled
// loop's last loop latch is guaranteed to be in the outermost loop after
// deleteLoopFromQueue updates LoopInfo.
Loop *LatchLoop = LI->getLoopFor(Latches.back());
if (!OuterL->contains(LatchLoop))
while (OuterL->getParentLoop() != LatchLoop)
OuterL = OuterL->getParentLoop();
formLCSSARecursively(*OuterL, *DT, LI, SE);
}
}
return true;
}
/// Given an llvm.loop loop id metadata node, returns the loop hint metadata
/// node with the given name (for example, "llvm.loop.unroll.count"). If no
/// such metadata node exists, then nullptr is returned.
MDNode *llvm::GetUnrollMetadata(MDNode *LoopID, StringRef Name) {
// First operand should refer to the loop id itself.
assert(LoopID->getNumOperands() > 0 && "requires at least one operand");
assert(LoopID->getOperand(0) == LoopID && "invalid loop id");
for (unsigned i = 1, e = LoopID->getNumOperands(); i < e; ++i) {
MDNode *MD = dyn_cast<MDNode>(LoopID->getOperand(i));
if (!MD)
continue;
MDString *S = dyn_cast<MDString>(MD->getOperand(0));
if (!S)
continue;
if (Name.equals(S->getString()))
return MD;
}
return nullptr;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/CMakeLists.txt | add_llvm_library(LLVMTransformUtils
ASanStackFrameLayout.cpp
AddDiscriminators.cpp
BasicBlockUtils.cpp
BreakCriticalEdges.cpp
BuildLibCalls.cpp
BypassSlowDivision.cpp
CloneFunction.cpp
CloneModule.cpp
CmpInstAnalysis.cpp
CodeExtractor.cpp
CtorUtils.cpp
DemoteRegToStack.cpp
FlattenCFG.cpp
GlobalStatus.cpp
InlineFunction.cpp
InstructionNamer.cpp
IntegerDivision.cpp
LCSSA.cpp
Local.cpp
LoopSimplify.cpp
LoopSimplifyId.cpp
LoopUnroll.cpp
LoopUnrollRuntime.cpp
LoopUtils.cpp
LoopVersioning.cpp
LowerInvoke.cpp
LowerSwitch.cpp
Mem2Reg.cpp
MetaRenamer.cpp
ModuleUtils.cpp
PromoteMemoryToRegister.cpp
SSAUpdater.cpp
SimplifyCFG.cpp
SimplifyIndVar.cpp
SimplifyInstructions.cpp
SimplifyLibCalls.cpp
SymbolRewriter.cpp
UnifyFunctionExitNodes.cpp
Utils.cpp
ValueMapper.cpp
ADDITIONAL_HEADER_DIRS
${LLVM_MAIN_INCLUDE_DIR}/llvm/Transforms
${LLVM_MAIN_INCLUDE_DIR}/llvm/Transforms/Utils
)
add_dependencies(LLVMTransformUtils intrinsics_gen)
target_link_libraries(LLVMTransformUtils PUBLIC LLVMDXIL) # HLSL Change |
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/LowerSwitch.cpp | //===- LowerSwitch.cpp - Eliminate Switch instructions --------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// The LowerSwitch transformation rewrites switch instructions with a sequence
// of branches, which allows targets to get away with not implementing the
// switch instruction until it is convenient.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Scalar.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/Pass.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/UnifyFunctionExitNodes.h"
#include <algorithm>
using namespace llvm;
#define DEBUG_TYPE "lower-switch"
namespace {
struct IntRange {
int64_t Low, High;
};
// Return true iff R is covered by Ranges.
static bool IsInRanges(const IntRange &R,
const std::vector<IntRange> &Ranges) {
// Note: Ranges must be sorted, non-overlapping and non-adjacent.
// Find the first range whose High field is >= R.High,
// then check if the Low field is <= R.Low. If so, we
// have a Range that covers R.
auto I = std::lower_bound(
Ranges.begin(), Ranges.end(), R,
[](const IntRange &A, const IntRange &B) { return A.High < B.High; });
return I != Ranges.end() && I->Low <= R.Low;
}
/// LowerSwitch Pass - Replace all SwitchInst instructions with chained branch
/// instructions.
class LowerSwitch : public FunctionPass {
public:
static char ID; // Pass identification, replacement for typeid
LowerSwitch() : FunctionPass(ID) {
initializeLowerSwitchPass(*PassRegistry::getPassRegistry());
}
bool runOnFunction(Function &F) override;
void getAnalysisUsage(AnalysisUsage &AU) const override {
// This is a cluster of orthogonal Transforms
AU.addPreserved<UnifyFunctionExitNodes>();
AU.addPreservedID(LowerInvokePassID);
}
struct CaseRange {
ConstantInt* Low;
ConstantInt* High;
BasicBlock* BB;
CaseRange(ConstantInt *low, ConstantInt *high, BasicBlock *bb)
: Low(low), High(high), BB(bb) {}
};
typedef std::vector<CaseRange> CaseVector;
typedef std::vector<CaseRange>::iterator CaseItr;
private:
void processSwitchInst(SwitchInst *SI);
BasicBlock *switchConvert(CaseItr Begin, CaseItr End,
ConstantInt *LowerBound, ConstantInt *UpperBound,
Value *Val, BasicBlock *Predecessor,
BasicBlock *OrigBlock, BasicBlock *Default,
const std::vector<IntRange> &UnreachableRanges);
BasicBlock *newLeafBlock(CaseRange &Leaf, Value *Val, BasicBlock *OrigBlock,
BasicBlock *Default);
unsigned Clusterify(CaseVector &Cases, SwitchInst *SI);
};
/// The comparison function for sorting the switch case values in the vector.
/// WARNING: Case ranges should be disjoint!
struct CaseCmp {
bool operator () (const LowerSwitch::CaseRange& C1,
const LowerSwitch::CaseRange& C2) {
const ConstantInt* CI1 = cast<const ConstantInt>(C1.Low);
const ConstantInt* CI2 = cast<const ConstantInt>(C2.High);
return CI1->getValue().slt(CI2->getValue());
}
};
}
char LowerSwitch::ID = 0;
INITIALIZE_PASS(LowerSwitch, "lowerswitch",
"Lower SwitchInst's to branches", false, false)
// Publicly exposed interface to pass...
char &llvm::LowerSwitchID = LowerSwitch::ID;
// createLowerSwitchPass - Interface to this file...
FunctionPass *llvm::createLowerSwitchPass() {
return new LowerSwitch();
}
bool LowerSwitch::runOnFunction(Function &F) {
bool Changed = false;
for (Function::iterator I = F.begin(), E = F.end(); I != E; ) {
BasicBlock *Cur = I++; // Advance over block so we don't traverse new blocks
if (SwitchInst *SI = dyn_cast<SwitchInst>(Cur->getTerminator())) {
Changed = true;
processSwitchInst(SI);
}
}
return Changed;
}
// operator<< - Used for debugging purposes.
//
static raw_ostream& operator<<(raw_ostream &O,
const LowerSwitch::CaseVector &C)
LLVM_ATTRIBUTE_USED;
static raw_ostream& operator<<(raw_ostream &O,
const LowerSwitch::CaseVector &C) {
O << "[";
for (LowerSwitch::CaseVector::const_iterator B = C.begin(),
E = C.end(); B != E; ) {
O << *B->Low << " -" << *B->High;
if (++B != E) O << ", ";
}
return O << "]";
}
// \brief Update the first occurrence of the "switch statement" BB in the PHI
// node with the "new" BB. The other occurrences will:
//
// 1) Be updated by subsequent calls to this function. Switch statements may
// have more than one outcoming edge into the same BB if they all have the same
// value. When the switch statement is converted these incoming edges are now
// coming from multiple BBs.
// 2) Removed if subsequent incoming values now share the same case, i.e.,
// multiple outcome edges are condensed into one. This is necessary to keep the
// number of phi values equal to the number of branches to SuccBB.
static void fixPhis(BasicBlock *SuccBB, BasicBlock *OrigBB, BasicBlock *NewBB,
unsigned NumMergedCases) {
for (BasicBlock::iterator I = SuccBB->begin(), IE = SuccBB->getFirstNonPHI();
I != IE; ++I) {
PHINode *PN = cast<PHINode>(I);
// Only update the first occurence.
unsigned Idx = 0, E = PN->getNumIncomingValues();
unsigned LocalNumMergedCases = NumMergedCases;
for (; Idx != E; ++Idx) {
if (PN->getIncomingBlock(Idx) == OrigBB) {
PN->setIncomingBlock(Idx, NewBB);
break;
}
}
// Remove additional occurences coming from condensed cases and keep the
// number of incoming values equal to the number of branches to SuccBB.
SmallVector<unsigned, 8> Indices;
for (++Idx; LocalNumMergedCases > 0 && Idx < E; ++Idx)
if (PN->getIncomingBlock(Idx) == OrigBB) {
Indices.push_back(Idx);
LocalNumMergedCases--;
}
// Remove incoming values in the reverse order to prevent invalidating
// *successive* index.
for (auto III = Indices.rbegin(), IIE = Indices.rend(); III != IIE; ++III)
PN->removeIncomingValue(*III);
}
}
// switchConvert - Convert the switch statement into a binary lookup of
// the case values. The function recursively builds this tree.
// LowerBound and UpperBound are used to keep track of the bounds for Val
// that have already been checked by a block emitted by one of the previous
// calls to switchConvert in the call stack.
BasicBlock *
LowerSwitch::switchConvert(CaseItr Begin, CaseItr End, ConstantInt *LowerBound,
ConstantInt *UpperBound, Value *Val,
BasicBlock *Predecessor, BasicBlock *OrigBlock,
BasicBlock *Default,
const std::vector<IntRange> &UnreachableRanges) {
unsigned Size = End - Begin;
if (Size == 1) {
// Check if the Case Range is perfectly squeezed in between
// already checked Upper and Lower bounds. If it is then we can avoid
// emitting the code that checks if the value actually falls in the range
// because the bounds already tell us so.
if (Begin->Low == LowerBound && Begin->High == UpperBound) {
unsigned NumMergedCases = 0;
if (LowerBound && UpperBound)
NumMergedCases =
UpperBound->getSExtValue() - LowerBound->getSExtValue();
fixPhis(Begin->BB, OrigBlock, Predecessor, NumMergedCases);
return Begin->BB;
}
return newLeafBlock(*Begin, Val, OrigBlock, Default);
}
unsigned Mid = Size / 2;
std::vector<CaseRange> LHS(Begin, Begin + Mid);
DEBUG(dbgs() << "LHS: " << LHS << "\n");
std::vector<CaseRange> RHS(Begin + Mid, End);
DEBUG(dbgs() << "RHS: " << RHS << "\n");
CaseRange &Pivot = *(Begin + Mid);
DEBUG(dbgs() << "Pivot ==> "
<< Pivot.Low->getValue()
<< " -" << Pivot.High->getValue() << "\n");
// NewLowerBound here should never be the integer minimal value.
// This is because it is computed from a case range that is never
// the smallest, so there is always a case range that has at least
// a smaller value.
ConstantInt *NewLowerBound = Pivot.Low;
// Because NewLowerBound is never the smallest representable integer
// it is safe here to subtract one.
ConstantInt *NewUpperBound = ConstantInt::get(NewLowerBound->getContext(),
NewLowerBound->getValue() - 1);
if (!UnreachableRanges.empty()) {
// Check if the gap between LHS's highest and NewLowerBound is unreachable.
int64_t GapLow = LHS.back().High->getSExtValue() + 1;
int64_t GapHigh = NewLowerBound->getSExtValue() - 1;
IntRange Gap = { GapLow, GapHigh };
if (GapHigh >= GapLow && IsInRanges(Gap, UnreachableRanges))
NewUpperBound = LHS.back().High;
}
DEBUG(dbgs() << "LHS Bounds ==> ";
if (LowerBound) {
dbgs() << LowerBound->getSExtValue();
} else {
dbgs() << "NONE";
}
dbgs() << " - " << NewUpperBound->getSExtValue() << "\n";
dbgs() << "RHS Bounds ==> ";
dbgs() << NewLowerBound->getSExtValue() << " - ";
if (UpperBound) {
dbgs() << UpperBound->getSExtValue() << "\n";
} else {
dbgs() << "NONE\n";
});
// Create a new node that checks if the value is < pivot. Go to the
// left branch if it is and right branch if not.
Function* F = OrigBlock->getParent();
BasicBlock* NewNode = BasicBlock::Create(Val->getContext(), "NodeBlock");
ICmpInst* Comp = new ICmpInst(ICmpInst::ICMP_SLT,
Val, Pivot.Low, "Pivot");
BasicBlock *LBranch = switchConvert(LHS.begin(), LHS.end(), LowerBound,
NewUpperBound, Val, NewNode, OrigBlock,
Default, UnreachableRanges);
BasicBlock *RBranch = switchConvert(RHS.begin(), RHS.end(), NewLowerBound,
UpperBound, Val, NewNode, OrigBlock,
Default, UnreachableRanges);
Function::iterator FI = OrigBlock;
F->getBasicBlockList().insert(++FI, NewNode);
NewNode->getInstList().push_back(Comp);
BranchInst::Create(LBranch, RBranch, Comp, NewNode);
return NewNode;
}
// newLeafBlock - Create a new leaf block for the binary lookup tree. It
// checks if the switch's value == the case's value. If not, then it
// jumps to the default branch. At this point in the tree, the value
// can't be another valid case value, so the jump to the "default" branch
// is warranted.
//
BasicBlock* LowerSwitch::newLeafBlock(CaseRange& Leaf, Value* Val,
BasicBlock* OrigBlock,
BasicBlock* Default)
{
Function* F = OrigBlock->getParent();
BasicBlock* NewLeaf = BasicBlock::Create(Val->getContext(), "LeafBlock");
Function::iterator FI = OrigBlock;
F->getBasicBlockList().insert(++FI, NewLeaf);
// Emit comparison
ICmpInst* Comp = nullptr;
if (Leaf.Low == Leaf.High) {
// Make the seteq instruction...
Comp = new ICmpInst(*NewLeaf, ICmpInst::ICMP_EQ, Val,
Leaf.Low, "SwitchLeaf");
} else {
// Make range comparison
if (Leaf.Low->isMinValue(true /*isSigned*/)) {
// Val >= Min && Val <= Hi --> Val <= Hi
Comp = new ICmpInst(*NewLeaf, ICmpInst::ICMP_SLE, Val, Leaf.High,
"SwitchLeaf");
} else if (Leaf.Low->isZero()) {
// Val >= 0 && Val <= Hi --> Val <=u Hi
Comp = new ICmpInst(*NewLeaf, ICmpInst::ICMP_ULE, Val, Leaf.High,
"SwitchLeaf");
} else {
// Emit V-Lo <=u Hi-Lo
Constant* NegLo = ConstantExpr::getNeg(Leaf.Low);
Instruction* Add = BinaryOperator::CreateAdd(Val, NegLo,
Val->getName()+".off",
NewLeaf);
Constant *UpperBound = ConstantExpr::getAdd(NegLo, Leaf.High);
Comp = new ICmpInst(*NewLeaf, ICmpInst::ICMP_ULE, Add, UpperBound,
"SwitchLeaf");
}
}
// Make the conditional branch...
BasicBlock* Succ = Leaf.BB;
BranchInst::Create(Succ, Default, Comp, NewLeaf);
// If there were any PHI nodes in this successor, rewrite one entry
// from OrigBlock to come from NewLeaf.
for (BasicBlock::iterator I = Succ->begin(); isa<PHINode>(I); ++I) {
PHINode* PN = cast<PHINode>(I);
// Remove all but one incoming entries from the cluster
uint64_t Range = Leaf.High->getSExtValue() -
Leaf.Low->getSExtValue();
for (uint64_t j = 0; j < Range; ++j) {
PN->removeIncomingValue(OrigBlock);
}
int BlockIdx = PN->getBasicBlockIndex(OrigBlock);
assert(BlockIdx != -1 && "Switch didn't go to this successor??");
PN->setIncomingBlock((unsigned)BlockIdx, NewLeaf);
}
return NewLeaf;
}
// Clusterify - Transform simple list of Cases into list of CaseRange's
unsigned LowerSwitch::Clusterify(CaseVector& Cases, SwitchInst *SI) {
unsigned numCmps = 0;
// Start with "simple" cases
for (SwitchInst::CaseIt i = SI->case_begin(), e = SI->case_end(); i != e; ++i)
Cases.push_back(CaseRange(i.getCaseValue(), i.getCaseValue(),
i.getCaseSuccessor()));
std::sort(Cases.begin(), Cases.end(), CaseCmp());
// Merge case into clusters
if (Cases.size() >= 2) {
CaseItr I = Cases.begin();
for (CaseItr J = std::next(I), E = Cases.end(); J != E; ++J) {
int64_t nextValue = J->Low->getSExtValue();
int64_t currentValue = I->High->getSExtValue();
BasicBlock* nextBB = J->BB;
BasicBlock* currentBB = I->BB;
// If the two neighboring cases go to the same destination, merge them
// into a single case.
assert(nextValue > currentValue && "Cases should be strictly ascending");
if ((nextValue == currentValue + 1) && (currentBB == nextBB)) {
I->High = J->High;
// FIXME: Combine branch weights.
} else if (++I != J) {
*I = *J;
}
}
Cases.erase(std::next(I), Cases.end());
}
for (CaseItr I=Cases.begin(), E=Cases.end(); I!=E; ++I, ++numCmps) {
if (I->Low != I->High)
// A range counts double, since it requires two compares.
++numCmps;
}
return numCmps;
}
// processSwitchInst - Replace the specified switch instruction with a sequence
// of chained if-then insts in a balanced binary search.
//
void LowerSwitch::processSwitchInst(SwitchInst *SI) {
BasicBlock *CurBlock = SI->getParent();
BasicBlock *OrigBlock = CurBlock;
Function *F = CurBlock->getParent();
Value *Val = SI->getCondition(); // The value we are switching on...
BasicBlock* Default = SI->getDefaultDest();
// If there is only the default destination, just branch.
if (!SI->getNumCases()) {
BranchInst::Create(Default, CurBlock);
SI->eraseFromParent();
return;
}
// Prepare cases vector.
CaseVector Cases;
unsigned numCmps = Clusterify(Cases, SI);
DEBUG(dbgs() << "Clusterify finished. Total clusters: " << Cases.size()
<< ". Total compares: " << numCmps << "\n");
DEBUG(dbgs() << "Cases: " << Cases << "\n");
(void)numCmps;
ConstantInt *LowerBound = nullptr;
ConstantInt *UpperBound = nullptr;
std::vector<IntRange> UnreachableRanges;
if (isa<UnreachableInst>(Default->getFirstNonPHIOrDbg())) {
// Make the bounds tightly fitted around the case value range, becase we
// know that the value passed to the switch must be exactly one of the case
// values.
assert(!Cases.empty());
LowerBound = Cases.front().Low;
UpperBound = Cases.back().High;
DenseMap<BasicBlock *, unsigned> Popularity;
unsigned MaxPop = 0;
BasicBlock *PopSucc = nullptr;
IntRange R = { INT64_MIN, INT64_MAX };
UnreachableRanges.push_back(R);
for (const auto &I : Cases) {
int64_t Low = I.Low->getSExtValue();
int64_t High = I.High->getSExtValue();
IntRange &LastRange = UnreachableRanges.back();
if (LastRange.Low == Low) {
// There is nothing left of the previous range.
UnreachableRanges.pop_back();
} else {
// Terminate the previous range.
assert(Low > LastRange.Low);
LastRange.High = Low - 1;
}
if (High != INT64_MAX) {
IntRange R = { High + 1, INT64_MAX };
UnreachableRanges.push_back(R);
}
// Count popularity.
int64_t N = High - Low + 1;
unsigned &Pop = Popularity[I.BB];
if ((Pop += N) > MaxPop) {
MaxPop = Pop;
PopSucc = I.BB;
}
}
#ifndef NDEBUG
/* UnreachableRanges should be sorted and the ranges non-adjacent. */
for (auto I = UnreachableRanges.begin(), E = UnreachableRanges.end();
I != E; ++I) {
assert(I->Low <= I->High);
auto Next = I + 1;
if (Next != E) {
assert(Next->Low > I->High);
}
}
#endif
// Use the most popular block as the new default, reducing the number of
// cases.
assert(MaxPop > 0 && PopSucc);
Default = PopSucc;
Cases.erase(std::remove_if(
Cases.begin(), Cases.end(),
[PopSucc](const CaseRange &R) { return R.BB == PopSucc; }),
Cases.end());
// If there are no cases left, just branch.
if (Cases.empty()) {
BranchInst::Create(Default, CurBlock);
SI->eraseFromParent();
return;
}
}
// Create a new, empty default block so that the new hierarchy of
// if-then statements go to this and the PHI nodes are happy.
BasicBlock *NewDefault = BasicBlock::Create(SI->getContext(), "NewDefault");
F->getBasicBlockList().insert(Default, NewDefault);
BranchInst::Create(Default, NewDefault);
// If there is an entry in any PHI nodes for the default edge, make sure
// to update them as well.
for (BasicBlock::iterator I = Default->begin(); isa<PHINode>(I); ++I) {
PHINode *PN = cast<PHINode>(I);
int BlockIdx = PN->getBasicBlockIndex(OrigBlock);
assert(BlockIdx != -1 && "Switch didn't go to this successor??");
PN->setIncomingBlock((unsigned)BlockIdx, NewDefault);
}
BasicBlock *SwitchBlock =
switchConvert(Cases.begin(), Cases.end(), LowerBound, UpperBound, Val,
OrigBlock, OrigBlock, NewDefault, UnreachableRanges);
// Branch to our shiny new if-then stuff...
BranchInst::Create(SwitchBlock, OrigBlock);
// We are now done with the switch instruction, delete it.
BasicBlock *OldDefault = SI->getDefaultDest();
CurBlock->getInstList().erase(SI);
// If the Default block has no more predecessors just remove it.
if (pred_begin(OldDefault) == pred_end(OldDefault))
DeleteDeadBlock(OldDefault);
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/CloneFunction.cpp | //===- CloneFunction.cpp - Clone a function into another function ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the CloneFunctionInto interface, which is used as the
// low-level function cloner. This is used by the CloneFunction and function
// inliner to do the dirty work of copying the body of a function around.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/Cloning.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/Module.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/ValueMapper.h"
#include <map>
using namespace llvm;
/// See comments in Cloning.h.
BasicBlock *llvm::CloneBasicBlock(const BasicBlock *BB,
ValueToValueMapTy &VMap,
const Twine &NameSuffix, Function *F,
ClonedCodeInfo *CodeInfo) {
BasicBlock *NewBB = BasicBlock::Create(BB->getContext(), "", F);
if (BB->hasName()) NewBB->setName(BB->getName()+NameSuffix);
bool hasCalls = false, hasDynamicAllocas = false, hasStaticAllocas = false;
// Loop over all instructions, and copy them over.
for (BasicBlock::const_iterator II = BB->begin(), IE = BB->end();
II != IE; ++II) {
Instruction *NewInst = II->clone();
if (II->hasName())
NewInst->setName(II->getName()+NameSuffix);
NewBB->getInstList().push_back(NewInst);
VMap[II] = NewInst; // Add instruction map to value.
hasCalls |= (isa<CallInst>(II) && !isa<DbgInfoIntrinsic>(II));
if (const AllocaInst *AI = dyn_cast<AllocaInst>(II)) {
if (isa<ConstantInt>(AI->getArraySize()))
hasStaticAllocas = true;
else
hasDynamicAllocas = true;
}
}
if (CodeInfo) {
CodeInfo->ContainsCalls |= hasCalls;
CodeInfo->ContainsDynamicAllocas |= hasDynamicAllocas;
CodeInfo->ContainsDynamicAllocas |= hasStaticAllocas &&
BB != &BB->getParent()->getEntryBlock();
}
return NewBB;
}
// Clone OldFunc into NewFunc, transforming the old arguments into references to
// VMap values.
//
void llvm::CloneFunctionInto(Function *NewFunc, const Function *OldFunc,
ValueToValueMapTy &VMap,
bool ModuleLevelChanges,
SmallVectorImpl<ReturnInst*> &Returns,
const char *NameSuffix, ClonedCodeInfo *CodeInfo,
ValueMapTypeRemapper *TypeMapper,
ValueMaterializer *Materializer) {
assert(NameSuffix && "NameSuffix cannot be null!");
#ifndef NDEBUG
for (Function::const_arg_iterator I = OldFunc->arg_begin(),
E = OldFunc->arg_end(); I != E; ++I)
assert(VMap.count(I) && "No mapping from source argument specified!");
#endif
// Copy all attributes other than those stored in the AttributeSet. We need
// to remap the parameter indices of the AttributeSet.
AttributeSet NewAttrs = NewFunc->getAttributes();
NewFunc->copyAttributesFrom(OldFunc);
NewFunc->setAttributes(NewAttrs);
AttributeSet OldAttrs = OldFunc->getAttributes();
// Clone any argument attributes that are present in the VMap.
for (const Argument &OldArg : OldFunc->args())
if (Argument *NewArg = dyn_cast<Argument>(VMap[&OldArg])) {
AttributeSet attrs =
OldAttrs.getParamAttributes(OldArg.getArgNo() + 1);
if (attrs.getNumSlots() > 0)
NewArg->addAttr(attrs);
}
NewFunc->setAttributes(
NewFunc->getAttributes()
.addAttributes(NewFunc->getContext(), AttributeSet::ReturnIndex,
OldAttrs.getRetAttributes())
.addAttributes(NewFunc->getContext(), AttributeSet::FunctionIndex,
OldAttrs.getFnAttributes()));
// Loop over all of the basic blocks in the function, cloning them as
// appropriate. Note that we save BE this way in order to handle cloning of
// recursive functions into themselves.
//
for (Function::const_iterator BI = OldFunc->begin(), BE = OldFunc->end();
BI != BE; ++BI) {
const BasicBlock &BB = *BI;
// Create a new basic block and copy instructions into it!
BasicBlock *CBB = CloneBasicBlock(&BB, VMap, NameSuffix, NewFunc, CodeInfo);
// Add basic block mapping.
VMap[&BB] = CBB;
// It is only legal to clone a function if a block address within that
// function is never referenced outside of the function. Given that, we
// want to map block addresses from the old function to block addresses in
// the clone. (This is different from the generic ValueMapper
// implementation, which generates an invalid blockaddress when
// cloning a function.)
if (BB.hasAddressTaken()) {
Constant *OldBBAddr = BlockAddress::get(const_cast<Function*>(OldFunc),
const_cast<BasicBlock*>(&BB));
VMap[OldBBAddr] = BlockAddress::get(NewFunc, CBB);
}
// Note return instructions for the caller.
if (ReturnInst *RI = dyn_cast<ReturnInst>(CBB->getTerminator()))
Returns.push_back(RI);
}
// Loop over all of the instructions in the function, fixing up operand
// references as we go. This uses VMap to do all the hard work.
for (Function::iterator BB = cast<BasicBlock>(VMap[OldFunc->begin()]),
BE = NewFunc->end(); BB != BE; ++BB)
// Loop over all instructions, fixing each one as we find it...
for (BasicBlock::iterator II = BB->begin(); II != BB->end(); ++II)
RemapInstruction(II, VMap,
ModuleLevelChanges ? RF_None : RF_NoModuleLevelChanges,
TypeMapper, Materializer);
}
// Find the MDNode which corresponds to the subprogram data that described F.
static DISubprogram *FindSubprogram(const Function *F,
DebugInfoFinder &Finder) {
for (DISubprogram *Subprogram : Finder.subprograms()) {
if (Subprogram->describes(F))
return Subprogram;
}
return nullptr;
}
// Add an operand to an existing MDNode. The new operand will be added at the
// back of the operand list.
static void AddOperand(DICompileUnit *CU, DISubprogramArray SPs,
Metadata *NewSP) {
SmallVector<Metadata *, 16> NewSPs;
NewSPs.reserve(SPs.size() + 1);
for (auto *SP : SPs)
NewSPs.push_back(SP);
NewSPs.push_back(NewSP);
CU->replaceSubprograms(MDTuple::get(CU->getContext(), NewSPs));
}
// Clone the module-level debug info associated with OldFunc. The cloned data
// will point to NewFunc instead.
static void CloneDebugInfoMetadata(Function *NewFunc, const Function *OldFunc,
ValueToValueMapTy &VMap) {
DebugInfoFinder Finder;
Finder.processModule(*OldFunc->getParent());
const DISubprogram *OldSubprogramMDNode = FindSubprogram(OldFunc, Finder);
if (!OldSubprogramMDNode) return;
// Ensure that OldFunc appears in the map.
// (if it's already there it must point to NewFunc anyway)
VMap[OldFunc] = NewFunc;
auto *NewSubprogram =
cast<DISubprogram>(MapMetadata(OldSubprogramMDNode, VMap));
for (auto *CU : Finder.compile_units()) {
auto Subprograms = CU->getSubprograms();
// If the compile unit's function list contains the old function, it should
// also contain the new one.
for (auto *SP : Subprograms) {
if (SP == OldSubprogramMDNode) {
AddOperand(CU, Subprograms, NewSubprogram);
break;
}
}
}
}
/// Return a copy of the specified function, but without
/// embedding the function into another module. Also, any references specified
/// in the VMap are changed to refer to their mapped value instead of the
/// original one. If any of the arguments to the function are in the VMap,
/// the arguments are deleted from the resultant function. The VMap is
/// updated to include mappings from all of the instructions and basicblocks in
/// the function from their old to new values.
///
Function *llvm::CloneFunction(const Function *F, ValueToValueMapTy &VMap,
bool ModuleLevelChanges,
ClonedCodeInfo *CodeInfo) {
std::vector<Type*> ArgTypes;
// The user might be deleting arguments to the function by specifying them in
// the VMap. If so, we need to not add the arguments to the arg ty vector
//
for (Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end();
I != E; ++I)
if (VMap.count(I) == 0) // Haven't mapped the argument to anything yet?
ArgTypes.push_back(I->getType());
// Create a new function type...
FunctionType *FTy = FunctionType::get(F->getFunctionType()->getReturnType(),
ArgTypes, F->getFunctionType()->isVarArg());
// Create the new function...
Function *NewF = Function::Create(FTy, F->getLinkage(), F->getName());
// Loop over the arguments, copying the names of the mapped arguments over...
Function::arg_iterator DestI = NewF->arg_begin();
for (Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end();
I != E; ++I)
if (VMap.count(I) == 0) { // Is this argument preserved?
DestI->setName(I->getName()); // Copy the name over...
VMap[I] = DestI++; // Add mapping to VMap
}
if (ModuleLevelChanges)
CloneDebugInfoMetadata(NewF, F, VMap);
SmallVector<ReturnInst*, 8> Returns; // Ignore returns cloned.
CloneFunctionInto(NewF, F, VMap, ModuleLevelChanges, Returns, "", CodeInfo);
return NewF;
}
namespace {
/// This is a private class used to implement CloneAndPruneFunctionInto.
struct PruningFunctionCloner {
Function *NewFunc;
const Function *OldFunc;
ValueToValueMapTy &VMap;
bool ModuleLevelChanges;
const char *NameSuffix;
ClonedCodeInfo *CodeInfo;
CloningDirector *Director;
ValueMapTypeRemapper *TypeMapper;
ValueMaterializer *Materializer;
public:
PruningFunctionCloner(Function *newFunc, const Function *oldFunc,
ValueToValueMapTy &valueMap, bool moduleLevelChanges,
const char *nameSuffix, ClonedCodeInfo *codeInfo,
CloningDirector *Director)
: NewFunc(newFunc), OldFunc(oldFunc), VMap(valueMap),
ModuleLevelChanges(moduleLevelChanges), NameSuffix(nameSuffix),
CodeInfo(codeInfo), Director(Director) {
// These are optional components. The Director may return null.
if (Director) {
TypeMapper = Director->getTypeRemapper();
Materializer = Director->getValueMaterializer();
} else {
TypeMapper = nullptr;
Materializer = nullptr;
}
}
/// The specified block is found to be reachable, clone it and
/// anything that it can reach.
void CloneBlock(const BasicBlock *BB,
BasicBlock::const_iterator StartingInst,
std::vector<const BasicBlock*> &ToClone);
};
}
/// The specified block is found to be reachable, clone it and
/// anything that it can reach.
void PruningFunctionCloner::CloneBlock(const BasicBlock *BB,
BasicBlock::const_iterator StartingInst,
std::vector<const BasicBlock*> &ToClone){
WeakTrackingVH &BBEntry = VMap[BB];
// Have we already cloned this block?
if (BBEntry) return;
// Nope, clone it now.
BasicBlock *NewBB;
BBEntry = NewBB = BasicBlock::Create(BB->getContext());
if (BB->hasName()) NewBB->setName(BB->getName()+NameSuffix);
// It is only legal to clone a function if a block address within that
// function is never referenced outside of the function. Given that, we
// want to map block addresses from the old function to block addresses in
// the clone. (This is different from the generic ValueMapper
// implementation, which generates an invalid blockaddress when
// cloning a function.)
//
// Note that we don't need to fix the mapping for unreachable blocks;
// the default mapping there is safe.
if (BB->hasAddressTaken()) {
Constant *OldBBAddr = BlockAddress::get(const_cast<Function*>(OldFunc),
const_cast<BasicBlock*>(BB));
VMap[OldBBAddr] = BlockAddress::get(NewFunc, NewBB);
}
bool hasCalls = false, hasDynamicAllocas = false, hasStaticAllocas = false;
// Loop over all instructions, and copy them over, DCE'ing as we go. This
// loop doesn't include the terminator.
for (BasicBlock::const_iterator II = StartingInst, IE = --BB->end();
II != IE; ++II) {
// If the "Director" remaps the instruction, don't clone it.
if (Director) {
CloningDirector::CloningAction Action
= Director->handleInstruction(VMap, II, NewBB);
// If the cloning director says stop, we want to stop everything, not
// just break out of the loop (which would cause the terminator to be
// cloned). The cloning director is responsible for inserting a proper
// terminator into the new basic block in this case.
if (Action == CloningDirector::StopCloningBB)
return;
// If the cloning director says skip, continue to the next instruction.
// In this case, the cloning director is responsible for mapping the
// skipped instruction to some value that is defined in the new
// basic block.
if (Action == CloningDirector::SkipInstruction)
continue;
}
Instruction *NewInst = II->clone();
// Eagerly remap operands to the newly cloned instruction, except for PHI
// nodes for which we defer processing until we update the CFG.
if (!isa<PHINode>(NewInst)) {
RemapInstruction(NewInst, VMap,
ModuleLevelChanges ? RF_None : RF_NoModuleLevelChanges,
TypeMapper, Materializer);
// If we can simplify this instruction to some other value, simply add
// a mapping to that value rather than inserting a new instruction into
// the basic block.
if (Value *V =
SimplifyInstruction(NewInst, BB->getModule()->getDataLayout())) {
// On the off-chance that this simplifies to an instruction in the old
// function, map it back into the new function.
if (Value *MappedV = VMap.lookup(V))
V = MappedV;
VMap[II] = V;
delete NewInst;
continue;
}
}
if (II->hasName())
NewInst->setName(II->getName()+NameSuffix);
VMap[II] = NewInst; // Add instruction map to value.
NewBB->getInstList().push_back(NewInst);
hasCalls |= (isa<CallInst>(II) && !isa<DbgInfoIntrinsic>(II));
if (const AllocaInst *AI = dyn_cast<AllocaInst>(II)) {
if (isa<ConstantInt>(AI->getArraySize()))
hasStaticAllocas = true;
else
hasDynamicAllocas = true;
}
}
// Finally, clone over the terminator.
const TerminatorInst *OldTI = BB->getTerminator();
bool TerminatorDone = false;
if (Director) {
CloningDirector::CloningAction Action
= Director->handleInstruction(VMap, OldTI, NewBB);
// If the cloning director says stop, we want to stop everything, not
// just break out of the loop (which would cause the terminator to be
// cloned). The cloning director is responsible for inserting a proper
// terminator into the new basic block in this case.
if (Action == CloningDirector::StopCloningBB)
return;
if (Action == CloningDirector::CloneSuccessors) {
// If the director says to skip with a terminate instruction, we still
// need to clone this block's successors.
const TerminatorInst *TI = NewBB->getTerminator();
for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
ToClone.push_back(TI->getSuccessor(i));
return;
}
assert(Action != CloningDirector::SkipInstruction &&
"SkipInstruction is not valid for terminators.");
}
if (const BranchInst *BI = dyn_cast<BranchInst>(OldTI)) {
if (BI->isConditional()) {
// If the condition was a known constant in the callee...
ConstantInt *Cond = dyn_cast<ConstantInt>(BI->getCondition());
// Or is a known constant in the caller...
if (!Cond) {
Value *V = VMap[BI->getCondition()];
Cond = dyn_cast_or_null<ConstantInt>(V);
}
// Constant fold to uncond branch!
if (Cond) {
BasicBlock *Dest = BI->getSuccessor(!Cond->getZExtValue());
VMap[OldTI] = BranchInst::Create(Dest, NewBB);
ToClone.push_back(Dest);
TerminatorDone = true;
}
}
} else if (const SwitchInst *SI = dyn_cast<SwitchInst>(OldTI)) {
// If switching on a value known constant in the caller.
ConstantInt *Cond = dyn_cast<ConstantInt>(SI->getCondition());
if (!Cond) { // Or known constant after constant prop in the callee...
Value *V = VMap[SI->getCondition()];
Cond = dyn_cast_or_null<ConstantInt>(V);
}
if (Cond) { // Constant fold to uncond branch!
SwitchInst::ConstCaseIt Case = SI->findCaseValue(Cond);
BasicBlock *Dest = const_cast<BasicBlock*>(Case.getCaseSuccessor());
VMap[OldTI] = BranchInst::Create(Dest, NewBB);
ToClone.push_back(Dest);
TerminatorDone = true;
}
}
if (!TerminatorDone) {
Instruction *NewInst = OldTI->clone();
if (OldTI->hasName())
NewInst->setName(OldTI->getName()+NameSuffix);
NewBB->getInstList().push_back(NewInst);
VMap[OldTI] = NewInst; // Add instruction map to value.
// Recursively clone any reachable successor blocks.
const TerminatorInst *TI = BB->getTerminator();
for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
ToClone.push_back(TI->getSuccessor(i));
}
if (CodeInfo) {
CodeInfo->ContainsCalls |= hasCalls;
CodeInfo->ContainsDynamicAllocas |= hasDynamicAllocas;
CodeInfo->ContainsDynamicAllocas |= hasStaticAllocas &&
BB != &BB->getParent()->front();
}
}
/// This works like CloneAndPruneFunctionInto, except that it does not clone the
/// entire function. Instead it starts at an instruction provided by the caller
/// and copies (and prunes) only the code reachable from that instruction.
void llvm::CloneAndPruneIntoFromInst(Function *NewFunc, const Function *OldFunc,
const Instruction *StartingInst,
ValueToValueMapTy &VMap,
bool ModuleLevelChanges,
SmallVectorImpl<ReturnInst *> &Returns,
const char *NameSuffix,
ClonedCodeInfo *CodeInfo,
CloningDirector *Director) {
assert(NameSuffix && "NameSuffix cannot be null!");
ValueMapTypeRemapper *TypeMapper = nullptr;
ValueMaterializer *Materializer = nullptr;
if (Director) {
TypeMapper = Director->getTypeRemapper();
Materializer = Director->getValueMaterializer();
}
#ifndef NDEBUG
// If the cloning starts at the begining of the function, verify that
// the function arguments are mapped.
if (!StartingInst)
for (Function::const_arg_iterator II = OldFunc->arg_begin(),
E = OldFunc->arg_end(); II != E; ++II)
assert(VMap.count(II) && "No mapping from source argument specified!");
#endif
PruningFunctionCloner PFC(NewFunc, OldFunc, VMap, ModuleLevelChanges,
NameSuffix, CodeInfo, Director);
const BasicBlock *StartingBB;
if (StartingInst)
StartingBB = StartingInst->getParent();
else {
StartingBB = &OldFunc->getEntryBlock();
StartingInst = StartingBB->begin();
}
// Clone the entry block, and anything recursively reachable from it.
std::vector<const BasicBlock*> CloneWorklist;
PFC.CloneBlock(StartingBB, StartingInst, CloneWorklist);
while (!CloneWorklist.empty()) {
const BasicBlock *BB = CloneWorklist.back();
CloneWorklist.pop_back();
PFC.CloneBlock(BB, BB->begin(), CloneWorklist);
}
// Loop over all of the basic blocks in the old function. If the block was
// reachable, we have cloned it and the old block is now in the value map:
// insert it into the new function in the right order. If not, ignore it.
//
// Defer PHI resolution until rest of function is resolved.
SmallVector<const PHINode*, 16> PHIToResolve;
for (Function::const_iterator BI = OldFunc->begin(), BE = OldFunc->end();
BI != BE; ++BI) {
Value *V = VMap[BI];
BasicBlock *NewBB = cast_or_null<BasicBlock>(V);
if (!NewBB) continue; // Dead block.
// Add the new block to the new function.
NewFunc->getBasicBlockList().push_back(NewBB);
// Handle PHI nodes specially, as we have to remove references to dead
// blocks.
for (BasicBlock::const_iterator I = BI->begin(), E = BI->end(); I != E; ++I) {
// PHI nodes may have been remapped to non-PHI nodes by the caller or
// during the cloning process.
if (const PHINode *PN = dyn_cast<PHINode>(I)) {
if (isa<PHINode>(VMap[PN]))
PHIToResolve.push_back(PN);
else
break;
} else {
break;
}
}
// Finally, remap the terminator instructions, as those can't be remapped
// until all BBs are mapped.
RemapInstruction(NewBB->getTerminator(), VMap,
ModuleLevelChanges ? RF_None : RF_NoModuleLevelChanges,
TypeMapper, Materializer);
}
// Defer PHI resolution until rest of function is resolved, PHI resolution
// requires the CFG to be up-to-date.
for (unsigned phino = 0, e = PHIToResolve.size(); phino != e; ) {
const PHINode *OPN = PHIToResolve[phino];
unsigned NumPreds = OPN->getNumIncomingValues();
const BasicBlock *OldBB = OPN->getParent();
BasicBlock *NewBB = cast<BasicBlock>(VMap[OldBB]);
// Map operands for blocks that are live and remove operands for blocks
// that are dead.
for (; phino != PHIToResolve.size() &&
PHIToResolve[phino]->getParent() == OldBB; ++phino) {
OPN = PHIToResolve[phino];
PHINode *PN = cast<PHINode>(VMap[OPN]);
for (unsigned pred = 0, e = NumPreds; pred != e; ++pred) {
Value *V = VMap[PN->getIncomingBlock(pred)];
if (BasicBlock *MappedBlock = cast_or_null<BasicBlock>(V)) {
Value *InVal = MapValue(PN->getIncomingValue(pred),
VMap,
ModuleLevelChanges ? RF_None : RF_NoModuleLevelChanges);
assert(InVal && "Unknown input value?");
PN->setIncomingValue(pred, InVal);
PN->setIncomingBlock(pred, MappedBlock);
} else {
PN->removeIncomingValue(pred, false);
--pred, --e; // Revisit the next entry.
}
}
}
// The loop above has removed PHI entries for those blocks that are dead
// and has updated others. However, if a block is live (i.e. copied over)
// but its terminator has been changed to not go to this block, then our
// phi nodes will have invalid entries. Update the PHI nodes in this
// case.
PHINode *PN = cast<PHINode>(NewBB->begin());
NumPreds = std::distance(pred_begin(NewBB), pred_end(NewBB));
if (NumPreds != PN->getNumIncomingValues()) {
assert(NumPreds < PN->getNumIncomingValues());
// Count how many times each predecessor comes to this block.
std::map<BasicBlock*, unsigned> PredCount;
for (pred_iterator PI = pred_begin(NewBB), E = pred_end(NewBB);
PI != E; ++PI)
--PredCount[*PI];
// Figure out how many entries to remove from each PHI.
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
++PredCount[PN->getIncomingBlock(i)];
// At this point, the excess predecessor entries are positive in the
// map. Loop over all of the PHIs and remove excess predecessor
// entries.
BasicBlock::iterator I = NewBB->begin();
for (; (PN = dyn_cast<PHINode>(I)); ++I) {
for (std::map<BasicBlock*, unsigned>::iterator PCI =PredCount.begin(),
E = PredCount.end(); PCI != E; ++PCI) {
BasicBlock *Pred = PCI->first;
for (unsigned NumToRemove = PCI->second; NumToRemove; --NumToRemove)
PN->removeIncomingValue(Pred, false);
}
}
}
// If the loops above have made these phi nodes have 0 or 1 operand,
// replace them with undef or the input value. We must do this for
// correctness, because 0-operand phis are not valid.
PN = cast<PHINode>(NewBB->begin());
if (PN->getNumIncomingValues() == 0) {
BasicBlock::iterator I = NewBB->begin();
BasicBlock::const_iterator OldI = OldBB->begin();
while ((PN = dyn_cast<PHINode>(I++))) {
Value *NV = UndefValue::get(PN->getType());
PN->replaceAllUsesWith(NV);
assert(VMap[OldI] == PN && "VMap mismatch");
VMap[OldI] = NV;
PN->eraseFromParent();
++OldI;
}
}
}
// Make a second pass over the PHINodes now that all of them have been
// remapped into the new function, simplifying the PHINode and performing any
// recursive simplifications exposed. This will transparently update the
// WeakTrackingVH in the VMap. Notably, we rely on that so that if we coalesce
// two PHINodes, the iteration over the old PHIs remains valid, and the
// mapping will just map us to the new node (which may not even be a PHI
// node).
for (unsigned Idx = 0, Size = PHIToResolve.size(); Idx != Size; ++Idx)
if (PHINode *PN = dyn_cast<PHINode>(VMap[PHIToResolve[Idx]]))
recursivelySimplifyInstruction(PN);
// Now that the inlined function body has been fully constructed, go through
// and zap unconditional fall-through branches. This happens all the time when
// specializing code: code specialization turns conditional branches into
// uncond branches, and this code folds them.
Function::iterator Begin = cast<BasicBlock>(VMap[StartingBB]);
Function::iterator I = Begin;
while (I != NewFunc->end()) {
// Check if this block has become dead during inlining or other
// simplifications. Note that the first block will appear dead, as it has
// not yet been wired up properly.
if (I != Begin && (pred_begin(I) == pred_end(I) ||
I->getSinglePredecessor() == I)) {
BasicBlock *DeadBB = I++;
DeleteDeadBlock(DeadBB);
continue;
}
// We need to simplify conditional branches and switches with a constant
// operand. We try to prune these out when cloning, but if the
// simplification required looking through PHI nodes, those are only
// available after forming the full basic block. That may leave some here,
// and we still want to prune the dead code as early as possible.
ConstantFoldTerminator(I);
BranchInst *BI = dyn_cast<BranchInst>(I->getTerminator());
if (!BI || BI->isConditional()) { ++I; continue; }
BasicBlock *Dest = BI->getSuccessor(0);
if (!Dest->getSinglePredecessor()) {
++I; continue;
}
// We shouldn't be able to get single-entry PHI nodes here, as instsimplify
// above should have zapped all of them..
assert(!isa<PHINode>(Dest->begin()));
// We know all single-entry PHI nodes in the inlined function have been
// removed, so we just need to splice the blocks.
BI->eraseFromParent();
// Make all PHI nodes that referred to Dest now refer to I as their source.
Dest->replaceAllUsesWith(I);
// Move all the instructions in the succ to the pred.
I->getInstList().splice(I->end(), Dest->getInstList());
// Remove the dest block.
Dest->eraseFromParent();
// Do not increment I, iteratively merge all things this block branches to.
}
// Make a final pass over the basic blocks from the old function to gather
// any return instructions which survived folding. We have to do this here
// because we can iteratively remove and merge returns above.
for (Function::iterator I = cast<BasicBlock>(VMap[StartingBB]),
E = NewFunc->end();
I != E; ++I)
if (ReturnInst *RI = dyn_cast<ReturnInst>(I->getTerminator()))
Returns.push_back(RI);
}
/// This works exactly like CloneFunctionInto,
/// except that it does some simple constant prop and DCE on the fly. The
/// effect of this is to copy significantly less code in cases where (for
/// example) a function call with constant arguments is inlined, and those
/// constant arguments cause a significant amount of code in the callee to be
/// dead. Since this doesn't produce an exact copy of the input, it can't be
/// used for things like CloneFunction or CloneModule.
void llvm::CloneAndPruneFunctionInto(Function *NewFunc, const Function *OldFunc,
ValueToValueMapTy &VMap,
bool ModuleLevelChanges,
SmallVectorImpl<ReturnInst*> &Returns,
const char *NameSuffix,
ClonedCodeInfo *CodeInfo,
Instruction *TheCall) {
CloneAndPruneIntoFromInst(NewFunc, OldFunc, OldFunc->front().begin(), VMap,
ModuleLevelChanges, Returns, NameSuffix, CodeInfo,
nullptr);
}
/// \brief Remaps instructions in \p Blocks using the mapping in \p VMap.
void llvm::remapInstructionsInBlocks(
const SmallVectorImpl<BasicBlock *> &Blocks, ValueToValueMapTy &VMap) {
// Rewrite the code to refer to itself.
for (auto *BB : Blocks)
for (auto &Inst : *BB)
RemapInstruction(&Inst, VMap,
RF_NoModuleLevelChanges | RF_IgnoreMissingEntries);
}
/// \brief Clones a loop \p OrigLoop. Returns the loop and the blocks in \p
/// Blocks.
///
/// Updates LoopInfo and DominatorTree assuming the loop is dominated by block
/// \p LoopDomBB. Insert the new blocks before block specified in \p Before.
Loop *llvm::cloneLoopWithPreheader(BasicBlock *Before, BasicBlock *LoopDomBB,
Loop *OrigLoop, ValueToValueMapTy &VMap,
const Twine &NameSuffix, LoopInfo *LI,
DominatorTree *DT,
SmallVectorImpl<BasicBlock *> &Blocks) {
Function *F = OrigLoop->getHeader()->getParent();
Loop *ParentLoop = OrigLoop->getParentLoop();
Loop *NewLoop = new Loop();
if (ParentLoop)
ParentLoop->addChildLoop(NewLoop);
else
LI->addTopLevelLoop(NewLoop);
BasicBlock *OrigPH = OrigLoop->getLoopPreheader();
assert(OrigPH && "No preheader");
BasicBlock *NewPH = CloneBasicBlock(OrigPH, VMap, NameSuffix, F);
// To rename the loop PHIs.
VMap[OrigPH] = NewPH;
Blocks.push_back(NewPH);
// Update LoopInfo.
if (ParentLoop)
ParentLoop->addBasicBlockToLoop(NewPH, *LI);
// Update DominatorTree.
DT->addNewBlock(NewPH, LoopDomBB);
for (BasicBlock *BB : OrigLoop->getBlocks()) {
BasicBlock *NewBB = CloneBasicBlock(BB, VMap, NameSuffix, F);
VMap[BB] = NewBB;
// Update LoopInfo.
NewLoop->addBasicBlockToLoop(NewBB, *LI);
// Update DominatorTree.
BasicBlock *IDomBB = DT->getNode(BB)->getIDom()->getBlock();
DT->addNewBlock(NewBB, cast<BasicBlock>(VMap[IDomBB]));
Blocks.push_back(NewBB);
}
// Move them physically from the end of the block list.
F->getBasicBlockList().splice(Before, F->getBasicBlockList(), NewPH);
F->getBasicBlockList().splice(Before, F->getBasicBlockList(),
NewLoop->getHeader(), F->end());
return NewLoop;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/SimplifyLibCalls.cpp | //===------ SimplifyLibCalls.cpp - Library calls simplifier ---------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This is a utility pass used for testing the InstructionSimplify analysis.
// The analysis is applied to every instruction, and if it simplifies then the
// instruction is replaced by the simplification. If you are looking for a pass
// that performs serious instruction folding, use the instcombine pass instead.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/SimplifyLibCalls.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DiagnosticInfo.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Transforms/Utils/BuildLibCalls.h"
using namespace llvm;
using namespace PatternMatch;
#if 0 // HLSL Change Starts - option pending
static cl::opt<bool>
ColdErrorCalls("error-reporting-is-cold", cl::init(true), cl::Hidden,
cl::desc("Treat error-reporting calls as cold"));
static cl::opt<bool>
EnableUnsafeFPShrink("enable-double-float-shrink", cl::Hidden,
cl::init(false),
cl::desc("Enable unsafe double to float "
"shrinking for math lib calls"));
#else
static const bool ColdErrorCalls = true;
static const bool EnableUnsafeFPShrink = false;
#endif // HLSL Change Ends
//===----------------------------------------------------------------------===//
// Helper Functions
//===----------------------------------------------------------------------===//
static bool ignoreCallingConv(LibFunc::Func Func) {
switch (Func) {
case LibFunc::abs:
case LibFunc::labs:
case LibFunc::llabs:
case LibFunc::strlen:
return true;
default:
return false;
}
llvm_unreachable("All cases should be covered in the switch.");
}
/// isOnlyUsedInZeroEqualityComparison - Return true if it only matters that the
/// value is equal or not-equal to zero.
static bool isOnlyUsedInZeroEqualityComparison(Value *V) {
for (User *U : V->users()) {
if (ICmpInst *IC = dyn_cast<ICmpInst>(U))
if (IC->isEquality())
if (Constant *C = dyn_cast<Constant>(IC->getOperand(1)))
if (C->isNullValue())
continue;
// Unknown instruction.
return false;
}
return true;
}
/// isOnlyUsedInEqualityComparison - Return true if it is only used in equality
/// comparisons with With.
static bool isOnlyUsedInEqualityComparison(Value *V, Value *With) {
for (User *U : V->users()) {
if (ICmpInst *IC = dyn_cast<ICmpInst>(U))
if (IC->isEquality() && IC->getOperand(1) == With)
continue;
// Unknown instruction.
return false;
}
return true;
}
static bool callHasFloatingPointArgument(const CallInst *CI) {
for (CallInst::const_op_iterator it = CI->op_begin(), e = CI->op_end();
it != e; ++it) {
if ((*it)->getType()->isFloatingPointTy())
return true;
}
return false;
}
/// \brief Check whether the overloaded unary floating point function
/// corresponing to \a Ty is available.
static bool hasUnaryFloatFn(const TargetLibraryInfo *TLI, Type *Ty,
LibFunc::Func DoubleFn, LibFunc::Func FloatFn,
LibFunc::Func LongDoubleFn) {
switch (Ty->getTypeID()) {
case Type::FloatTyID:
return TLI->has(FloatFn);
case Type::DoubleTyID:
return TLI->has(DoubleFn);
default:
return TLI->has(LongDoubleFn);
}
}
/// \brief Returns whether \p F matches the signature expected for the
/// string/memory copying library function \p Func.
/// Acceptable functions are st[rp][n]?cpy, memove, memcpy, and memset.
/// Their fortified (_chk) counterparts are also accepted.
static bool checkStringCopyLibFuncSignature(Function *F, LibFunc::Func Func) {
const DataLayout &DL = F->getParent()->getDataLayout();
FunctionType *FT = F->getFunctionType();
LLVMContext &Context = F->getContext();
Type *PCharTy = Type::getInt8PtrTy(Context);
Type *SizeTTy = DL.getIntPtrType(Context);
unsigned NumParams = FT->getNumParams();
// All string libfuncs return the same type as the first parameter.
if (FT->getReturnType() != FT->getParamType(0))
return false;
switch (Func) {
default:
llvm_unreachable("Can't check signature for non-string-copy libfunc.");
case LibFunc::stpncpy_chk:
case LibFunc::strncpy_chk:
--NumParams; LLVM_FALLTHROUGH; // HLSL Change
case LibFunc::stpncpy:
case LibFunc::strncpy: {
if (NumParams != 3 || FT->getParamType(0) != FT->getParamType(1) ||
FT->getParamType(0) != PCharTy || !FT->getParamType(2)->isIntegerTy())
return false;
break;
}
case LibFunc::strcpy_chk:
case LibFunc::stpcpy_chk:
--NumParams; LLVM_FALLTHROUGH; // HLSL Change
case LibFunc::stpcpy:
case LibFunc::strcpy: {
if (NumParams != 2 || FT->getParamType(0) != FT->getParamType(1) ||
FT->getParamType(0) != PCharTy)
return false;
break;
}
case LibFunc::memmove_chk:
case LibFunc::memcpy_chk:
--NumParams; LLVM_FALLTHROUGH; // HLSL Change
case LibFunc::memmove:
case LibFunc::memcpy: {
if (NumParams != 3 || !FT->getParamType(0)->isPointerTy() ||
!FT->getParamType(1)->isPointerTy() || FT->getParamType(2) != SizeTTy)
return false;
break;
}
case LibFunc::memset_chk:
--NumParams; LLVM_FALLTHROUGH; // HLSL Change
case LibFunc::memset: {
if (NumParams != 3 || !FT->getParamType(0)->isPointerTy() ||
!FT->getParamType(1)->isIntegerTy() || FT->getParamType(2) != SizeTTy)
return false;
break;
}
}
// If this is a fortified libcall, the last parameter is a size_t.
if (NumParams == FT->getNumParams() - 1)
return FT->getParamType(FT->getNumParams() - 1) == SizeTTy;
return true;
}
//===----------------------------------------------------------------------===//
// String and Memory Library Call Optimizations
//===----------------------------------------------------------------------===//
Value *LibCallSimplifier::optimizeStrCat(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
// Verify the "strcat" function prototype.
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2||
FT->getReturnType() != B.getInt8PtrTy() ||
FT->getParamType(0) != FT->getReturnType() ||
FT->getParamType(1) != FT->getReturnType())
return nullptr;
// Extract some information from the instruction
Value *Dst = CI->getArgOperand(0);
Value *Src = CI->getArgOperand(1);
// See if we can get the length of the input string.
uint64_t Len = GetStringLength(Src);
if (Len == 0)
return nullptr;
--Len; // Unbias length.
// Handle the simple, do-nothing case: strcat(x, "") -> x
if (Len == 0)
return Dst;
return emitStrLenMemCpy(Src, Dst, Len, B);
}
Value *LibCallSimplifier::emitStrLenMemCpy(Value *Src, Value *Dst, uint64_t Len,
IRBuilder<> &B) {
// We need to find the end of the destination string. That's where the
// memory is to be moved to. We just generate a call to strlen.
Value *DstLen = EmitStrLen(Dst, B, DL, TLI);
if (!DstLen)
return nullptr;
// Now that we have the destination's length, we must index into the
// destination's pointer to get the actual memcpy destination (end of
// the string .. we're concatenating).
Value *CpyDst = B.CreateGEP(B.getInt8Ty(), Dst, DstLen, "endptr");
// We have enough information to now generate the memcpy call to do the
// concatenation for us. Make a memcpy to copy the nul byte with align = 1.
B.CreateMemCpy(CpyDst, Src,
ConstantInt::get(DL.getIntPtrType(Src->getContext()), Len + 1),
1);
return Dst;
}
Value *LibCallSimplifier::optimizeStrNCat(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
// Verify the "strncat" function prototype.
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 3 || FT->getReturnType() != B.getInt8PtrTy() ||
FT->getParamType(0) != FT->getReturnType() ||
FT->getParamType(1) != FT->getReturnType() ||
!FT->getParamType(2)->isIntegerTy())
return nullptr;
// Extract some information from the instruction
Value *Dst = CI->getArgOperand(0);
Value *Src = CI->getArgOperand(1);
uint64_t Len;
// We don't do anything if length is not constant
if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(CI->getArgOperand(2)))
Len = LengthArg->getZExtValue();
else
return nullptr;
// See if we can get the length of the input string.
uint64_t SrcLen = GetStringLength(Src);
if (SrcLen == 0)
return nullptr;
--SrcLen; // Unbias length.
// Handle the simple, do-nothing cases:
// strncat(x, "", c) -> x
// strncat(x, c, 0) -> x
if (SrcLen == 0 || Len == 0)
return Dst;
// We don't optimize this case
if (Len < SrcLen)
return nullptr;
// strncat(x, s, c) -> strcat(x, s)
// s is constant so the strcat can be optimized further
return emitStrLenMemCpy(Src, Dst, SrcLen, B);
}
Value *LibCallSimplifier::optimizeStrChr(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
// Verify the "strchr" function prototype.
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2 || FT->getReturnType() != B.getInt8PtrTy() ||
FT->getParamType(0) != FT->getReturnType() ||
!FT->getParamType(1)->isIntegerTy(32))
return nullptr;
Value *SrcStr = CI->getArgOperand(0);
// If the second operand is non-constant, see if we can compute the length
// of the input string and turn this into memchr.
ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
if (!CharC) {
uint64_t Len = GetStringLength(SrcStr);
if (Len == 0 || !FT->getParamType(1)->isIntegerTy(32)) // memchr needs i32.
return nullptr;
return EmitMemChr(SrcStr, CI->getArgOperand(1), // include nul.
ConstantInt::get(DL.getIntPtrType(CI->getContext()), Len),
B, DL, TLI);
}
// Otherwise, the character is a constant, see if the first argument is
// a string literal. If so, we can constant fold.
StringRef Str;
if (!getConstantStringInfo(SrcStr, Str)) {
if (CharC->isZero()) // strchr(p, 0) -> p + strlen(p)
return B.CreateGEP(B.getInt8Ty(), SrcStr, EmitStrLen(SrcStr, B, DL, TLI), "strchr");
return nullptr;
}
// Compute the offset, make sure to handle the case when we're searching for
// zero (a weird way to spell strlen).
size_t I = (0xFF & CharC->getSExtValue()) == 0
? Str.size()
: Str.find(CharC->getSExtValue());
if (I == StringRef::npos) // Didn't find the char. strchr returns null.
return Constant::getNullValue(CI->getType());
// strchr(s+n,c) -> gep(s+n+i,c)
return B.CreateGEP(B.getInt8Ty(), SrcStr, B.getInt64(I), "strchr");
}
Value *LibCallSimplifier::optimizeStrRChr(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
// Verify the "strrchr" function prototype.
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2 || FT->getReturnType() != B.getInt8PtrTy() ||
FT->getParamType(0) != FT->getReturnType() ||
!FT->getParamType(1)->isIntegerTy(32))
return nullptr;
Value *SrcStr = CI->getArgOperand(0);
ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
// Cannot fold anything if we're not looking for a constant.
if (!CharC)
return nullptr;
StringRef Str;
if (!getConstantStringInfo(SrcStr, Str)) {
// strrchr(s, 0) -> strchr(s, 0)
if (CharC->isZero())
return EmitStrChr(SrcStr, '\0', B, TLI);
return nullptr;
}
// Compute the offset.
size_t I = (0xFF & CharC->getSExtValue()) == 0
? Str.size()
: Str.rfind(CharC->getSExtValue());
if (I == StringRef::npos) // Didn't find the char. Return null.
return Constant::getNullValue(CI->getType());
// strrchr(s+n,c) -> gep(s+n+i,c)
return B.CreateGEP(B.getInt8Ty(), SrcStr, B.getInt64(I), "strrchr");
}
Value *LibCallSimplifier::optimizeStrCmp(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
// Verify the "strcmp" function prototype.
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2 || !FT->getReturnType()->isIntegerTy(32) ||
FT->getParamType(0) != FT->getParamType(1) ||
FT->getParamType(0) != B.getInt8PtrTy())
return nullptr;
Value *Str1P = CI->getArgOperand(0), *Str2P = CI->getArgOperand(1);
if (Str1P == Str2P) // strcmp(x,x) -> 0
return ConstantInt::get(CI->getType(), 0);
StringRef Str1, Str2;
bool HasStr1 = getConstantStringInfo(Str1P, Str1);
bool HasStr2 = getConstantStringInfo(Str2P, Str2);
// strcmp(x, y) -> cnst (if both x and y are constant strings)
if (HasStr1 && HasStr2)
return ConstantInt::get(CI->getType(), Str1.compare(Str2));
if (HasStr1 && Str1.empty()) // strcmp("", x) -> -*x
return B.CreateNeg(
B.CreateZExt(B.CreateLoad(Str2P, "strcmpload"), CI->getType()));
if (HasStr2 && Str2.empty()) // strcmp(x,"") -> *x
return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
// strcmp(P, "x") -> memcmp(P, "x", 2)
uint64_t Len1 = GetStringLength(Str1P);
uint64_t Len2 = GetStringLength(Str2P);
if (Len1 && Len2) {
return EmitMemCmp(Str1P, Str2P,
ConstantInt::get(DL.getIntPtrType(CI->getContext()),
std::min(Len1, Len2)),
B, DL, TLI);
}
return nullptr;
}
Value *LibCallSimplifier::optimizeStrNCmp(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
// Verify the "strncmp" function prototype.
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 3 || !FT->getReturnType()->isIntegerTy(32) ||
FT->getParamType(0) != FT->getParamType(1) ||
FT->getParamType(0) != B.getInt8PtrTy() ||
!FT->getParamType(2)->isIntegerTy())
return nullptr;
Value *Str1P = CI->getArgOperand(0), *Str2P = CI->getArgOperand(1);
if (Str1P == Str2P) // strncmp(x,x,n) -> 0
return ConstantInt::get(CI->getType(), 0);
// Get the length argument if it is constant.
uint64_t Length;
if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(CI->getArgOperand(2)))
Length = LengthArg->getZExtValue();
else
return nullptr;
if (Length == 0) // strncmp(x,y,0) -> 0
return ConstantInt::get(CI->getType(), 0);
if (Length == 1) // strncmp(x,y,1) -> memcmp(x,y,1)
return EmitMemCmp(Str1P, Str2P, CI->getArgOperand(2), B, DL, TLI);
StringRef Str1, Str2;
bool HasStr1 = getConstantStringInfo(Str1P, Str1);
bool HasStr2 = getConstantStringInfo(Str2P, Str2);
// strncmp(x, y) -> cnst (if both x and y are constant strings)
if (HasStr1 && HasStr2) {
StringRef SubStr1 = Str1.substr(0, Length);
StringRef SubStr2 = Str2.substr(0, Length);
return ConstantInt::get(CI->getType(), SubStr1.compare(SubStr2));
}
if (HasStr1 && Str1.empty()) // strncmp("", x, n) -> -*x
return B.CreateNeg(
B.CreateZExt(B.CreateLoad(Str2P, "strcmpload"), CI->getType()));
if (HasStr2 && Str2.empty()) // strncmp(x, "", n) -> *x
return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
return nullptr;
}
Value *LibCallSimplifier::optimizeStrCpy(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
if (!checkStringCopyLibFuncSignature(Callee, LibFunc::strcpy))
return nullptr;
Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
if (Dst == Src) // strcpy(x,x) -> x
return Src;
// See if we can get the length of the input string.
uint64_t Len = GetStringLength(Src);
if (Len == 0)
return nullptr;
// We have enough information to now generate the memcpy call to do the
// copy for us. Make a memcpy to copy the nul byte with align = 1.
B.CreateMemCpy(Dst, Src,
ConstantInt::get(DL.getIntPtrType(CI->getContext()), Len), 1);
return Dst;
}
Value *LibCallSimplifier::optimizeStpCpy(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
// Verify the "stpcpy" function prototype.
FunctionType *FT = Callee->getFunctionType();
if (!checkStringCopyLibFuncSignature(Callee, LibFunc::stpcpy))
return nullptr;
Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
if (Dst == Src) { // stpcpy(x,x) -> x+strlen(x)
Value *StrLen = EmitStrLen(Src, B, DL, TLI);
return StrLen ? B.CreateInBoundsGEP(B.getInt8Ty(), Dst, StrLen) : nullptr;
}
// See if we can get the length of the input string.
uint64_t Len = GetStringLength(Src);
if (Len == 0)
return nullptr;
Type *PT = FT->getParamType(0);
Value *LenV = ConstantInt::get(DL.getIntPtrType(PT), Len);
Value *DstEnd =
B.CreateGEP(B.getInt8Ty(), Dst, ConstantInt::get(DL.getIntPtrType(PT), Len - 1));
// We have enough information to now generate the memcpy call to do the
// copy for us. Make a memcpy to copy the nul byte with align = 1.
B.CreateMemCpy(Dst, Src, LenV, 1);
return DstEnd;
}
Value *LibCallSimplifier::optimizeStrNCpy(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
if (!checkStringCopyLibFuncSignature(Callee, LibFunc::strncpy))
return nullptr;
Value *Dst = CI->getArgOperand(0);
Value *Src = CI->getArgOperand(1);
Value *LenOp = CI->getArgOperand(2);
// See if we can get the length of the input string.
uint64_t SrcLen = GetStringLength(Src);
if (SrcLen == 0)
return nullptr;
--SrcLen;
if (SrcLen == 0) {
// strncpy(x, "", y) -> memset(x, '\0', y, 1)
B.CreateMemSet(Dst, B.getInt8('\0'), LenOp, 1);
return Dst;
}
uint64_t Len;
if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(LenOp))
Len = LengthArg->getZExtValue();
else
return nullptr;
if (Len == 0)
return Dst; // strncpy(x, y, 0) -> x
// Let strncpy handle the zero padding
if (Len > SrcLen + 1)
return nullptr;
Type *PT = FT->getParamType(0);
// strncpy(x, s, c) -> memcpy(x, s, c, 1) [s and c are constant]
B.CreateMemCpy(Dst, Src, ConstantInt::get(DL.getIntPtrType(PT), Len), 1);
return Dst;
}
Value *LibCallSimplifier::optimizeStrLen(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 1 || FT->getParamType(0) != B.getInt8PtrTy() ||
!FT->getReturnType()->isIntegerTy())
return nullptr;
Value *Src = CI->getArgOperand(0);
// Constant folding: strlen("xyz") -> 3
if (uint64_t Len = GetStringLength(Src))
return ConstantInt::get(CI->getType(), Len - 1);
// strlen(x?"foo":"bars") --> x ? 3 : 4
if (SelectInst *SI = dyn_cast<SelectInst>(Src)) {
uint64_t LenTrue = GetStringLength(SI->getTrueValue());
uint64_t LenFalse = GetStringLength(SI->getFalseValue());
if (LenTrue && LenFalse) {
Function *Caller = CI->getParent()->getParent();
emitOptimizationRemark(CI->getContext(), "simplify-libcalls", *Caller,
SI->getDebugLoc(),
"folded strlen(select) to select of constants");
return B.CreateSelect(SI->getCondition(),
ConstantInt::get(CI->getType(), LenTrue - 1),
ConstantInt::get(CI->getType(), LenFalse - 1));
}
}
// strlen(x) != 0 --> *x != 0
// strlen(x) == 0 --> *x == 0
if (isOnlyUsedInZeroEqualityComparison(CI))
return B.CreateZExt(B.CreateLoad(Src, "strlenfirst"), CI->getType());
return nullptr;
}
Value *LibCallSimplifier::optimizeStrPBrk(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2 || FT->getParamType(0) != B.getInt8PtrTy() ||
FT->getParamType(1) != FT->getParamType(0) ||
FT->getReturnType() != FT->getParamType(0))
return nullptr;
StringRef S1, S2;
bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
// strpbrk(s, "") -> nullptr
// strpbrk("", s) -> nullptr
if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
return Constant::getNullValue(CI->getType());
// Constant folding.
if (HasS1 && HasS2) {
size_t I = S1.find_first_of(S2);
if (I == StringRef::npos) // No match.
return Constant::getNullValue(CI->getType());
return B.CreateGEP(B.getInt8Ty(), CI->getArgOperand(0), B.getInt64(I), "strpbrk");
}
// strpbrk(s, "a") -> strchr(s, 'a')
if (HasS2 && S2.size() == 1)
return EmitStrChr(CI->getArgOperand(0), S2[0], B, TLI);
return nullptr;
}
Value *LibCallSimplifier::optimizeStrTo(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
if ((FT->getNumParams() != 2 && FT->getNumParams() != 3) ||
!FT->getParamType(0)->isPointerTy() ||
!FT->getParamType(1)->isPointerTy())
return nullptr;
Value *EndPtr = CI->getArgOperand(1);
if (isa<ConstantPointerNull>(EndPtr)) {
// With a null EndPtr, this function won't capture the main argument.
// It would be readonly too, except that it still may write to errno.
CI->addAttribute(1, Attribute::NoCapture);
}
return nullptr;
}
Value *LibCallSimplifier::optimizeStrSpn(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2 || FT->getParamType(0) != B.getInt8PtrTy() ||
FT->getParamType(1) != FT->getParamType(0) ||
!FT->getReturnType()->isIntegerTy())
return nullptr;
StringRef S1, S2;
bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
// strspn(s, "") -> 0
// strspn("", s) -> 0
if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
return Constant::getNullValue(CI->getType());
// Constant folding.
if (HasS1 && HasS2) {
size_t Pos = S1.find_first_not_of(S2);
if (Pos == StringRef::npos)
Pos = S1.size();
return ConstantInt::get(CI->getType(), Pos);
}
return nullptr;
}
Value *LibCallSimplifier::optimizeStrCSpn(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2 || FT->getParamType(0) != B.getInt8PtrTy() ||
FT->getParamType(1) != FT->getParamType(0) ||
!FT->getReturnType()->isIntegerTy())
return nullptr;
StringRef S1, S2;
bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
// strcspn("", s) -> 0
if (HasS1 && S1.empty())
return Constant::getNullValue(CI->getType());
// Constant folding.
if (HasS1 && HasS2) {
size_t Pos = S1.find_first_of(S2);
if (Pos == StringRef::npos)
Pos = S1.size();
return ConstantInt::get(CI->getType(), Pos);
}
// strcspn(s, "") -> strlen(s)
if (HasS2 && S2.empty())
return EmitStrLen(CI->getArgOperand(0), B, DL, TLI);
return nullptr;
}
Value *LibCallSimplifier::optimizeStrStr(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
!FT->getParamType(1)->isPointerTy() ||
!FT->getReturnType()->isPointerTy())
return nullptr;
// fold strstr(x, x) -> x.
if (CI->getArgOperand(0) == CI->getArgOperand(1))
return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
// fold strstr(a, b) == a -> strncmp(a, b, strlen(b)) == 0
if (isOnlyUsedInEqualityComparison(CI, CI->getArgOperand(0))) {
Value *StrLen = EmitStrLen(CI->getArgOperand(1), B, DL, TLI);
if (!StrLen)
return nullptr;
Value *StrNCmp = EmitStrNCmp(CI->getArgOperand(0), CI->getArgOperand(1),
StrLen, B, DL, TLI);
if (!StrNCmp)
return nullptr;
for (auto UI = CI->user_begin(), UE = CI->user_end(); UI != UE;) {
ICmpInst *Old = cast<ICmpInst>(*UI++);
Value *Cmp =
B.CreateICmp(Old->getPredicate(), StrNCmp,
ConstantInt::getNullValue(StrNCmp->getType()), "cmp");
replaceAllUsesWith(Old, Cmp);
}
return CI;
}
// See if either input string is a constant string.
StringRef SearchStr, ToFindStr;
bool HasStr1 = getConstantStringInfo(CI->getArgOperand(0), SearchStr);
bool HasStr2 = getConstantStringInfo(CI->getArgOperand(1), ToFindStr);
// fold strstr(x, "") -> x.
if (HasStr2 && ToFindStr.empty())
return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
// If both strings are known, constant fold it.
if (HasStr1 && HasStr2) {
size_t Offset = SearchStr.find(ToFindStr);
if (Offset == StringRef::npos) // strstr("foo", "bar") -> null
return Constant::getNullValue(CI->getType());
// strstr("abcd", "bc") -> gep((char*)"abcd", 1)
Value *Result = CastToCStr(CI->getArgOperand(0), B);
Result = B.CreateConstInBoundsGEP1_64(Result, Offset, "strstr");
return B.CreateBitCast(Result, CI->getType());
}
// fold strstr(x, "y") -> strchr(x, 'y').
if (HasStr2 && ToFindStr.size() == 1) {
Value *StrChr = EmitStrChr(CI->getArgOperand(0), ToFindStr[0], B, TLI);
return StrChr ? B.CreateBitCast(StrChr, CI->getType()) : nullptr;
}
return nullptr;
}
Value *LibCallSimplifier::optimizeMemChr(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 3 || !FT->getParamType(0)->isPointerTy() ||
!FT->getParamType(1)->isIntegerTy(32) ||
!FT->getParamType(2)->isIntegerTy() ||
!FT->getReturnType()->isPointerTy())
return nullptr;
Value *SrcStr = CI->getArgOperand(0);
ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
ConstantInt *LenC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
// memchr(x, y, 0) -> null
if (LenC && LenC->isNullValue())
return Constant::getNullValue(CI->getType());
// From now on we need at least constant length and string.
StringRef Str;
if (!LenC || !getConstantStringInfo(SrcStr, Str, 0, /*TrimAtNul=*/false))
return nullptr;
// Truncate the string to LenC. If Str is smaller than LenC we will still only
// scan the string, as reading past the end of it is undefined and we can just
// return null if we don't find the char.
Str = Str.substr(0, LenC->getZExtValue());
// If the char is variable but the input str and length are not we can turn
// this memchr call into a simple bit field test. Of course this only works
// when the return value is only checked against null.
//
// It would be really nice to reuse switch lowering here but we can't change
// the CFG at this point.
//
// memchr("\r\n", C, 2) != nullptr -> (C & ((1 << '\r') | (1 << '\n'))) != 0
// after bounds check.
if (!CharC && !Str.empty() && isOnlyUsedInZeroEqualityComparison(CI)) {
unsigned char Max =
*std::max_element(reinterpret_cast<const unsigned char *>(Str.begin()),
reinterpret_cast<const unsigned char *>(Str.end()));
// Make sure the bit field we're about to create fits in a register on the
// target.
// FIXME: On a 64 bit architecture this prevents us from using the
// interesting range of alpha ascii chars. We could do better by emitting
// two bitfields or shifting the range by 64 if no lower chars are used.
if (!DL.fitsInLegalInteger(Max + 1))
return nullptr;
// For the bit field use a power-of-2 type with at least 8 bits to avoid
// creating unnecessary illegal types.
unsigned char Width = NextPowerOf2(std::max((unsigned char)7, Max));
// Now build the bit field.
APInt Bitfield(Width, 0);
for (char C : Str)
Bitfield.setBit((unsigned char)C);
Value *BitfieldC = B.getInt(Bitfield);
// First check that the bit field access is within bounds.
Value *C = B.CreateZExtOrTrunc(CI->getArgOperand(1), BitfieldC->getType());
Value *Bounds = B.CreateICmp(ICmpInst::ICMP_ULT, C, B.getIntN(Width, Width),
"memchr.bounds");
// Create code that checks if the given bit is set in the field.
Value *Shl = B.CreateShl(B.getIntN(Width, 1ULL), C);
Value *Bits = B.CreateIsNotNull(B.CreateAnd(Shl, BitfieldC), "memchr.bits");
// Finally merge both checks and cast to pointer type. The inttoptr
// implicitly zexts the i1 to intptr type.
return B.CreateIntToPtr(B.CreateAnd(Bounds, Bits, "memchr"), CI->getType());
}
// Check if all arguments are constants. If so, we can constant fold.
if (!CharC)
return nullptr;
// Compute the offset.
size_t I = Str.find(CharC->getSExtValue() & 0xFF);
if (I == StringRef::npos) // Didn't find the char. memchr returns null.
return Constant::getNullValue(CI->getType());
// memchr(s+n,c,l) -> gep(s+n+i,c)
return B.CreateGEP(B.getInt8Ty(), SrcStr, B.getInt64(I), "memchr");
}
Value *LibCallSimplifier::optimizeMemCmp(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 3 || !FT->getParamType(0)->isPointerTy() ||
!FT->getParamType(1)->isPointerTy() ||
!FT->getReturnType()->isIntegerTy(32))
return nullptr;
Value *LHS = CI->getArgOperand(0), *RHS = CI->getArgOperand(1);
if (LHS == RHS) // memcmp(s,s,x) -> 0
return Constant::getNullValue(CI->getType());
// Make sure we have a constant length.
ConstantInt *LenC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
if (!LenC)
return nullptr;
uint64_t Len = LenC->getZExtValue();
if (Len == 0) // memcmp(s1,s2,0) -> 0
return Constant::getNullValue(CI->getType());
// memcmp(S1,S2,1) -> *(unsigned char*)LHS - *(unsigned char*)RHS
if (Len == 1) {
Value *LHSV = B.CreateZExt(B.CreateLoad(CastToCStr(LHS, B), "lhsc"),
CI->getType(), "lhsv");
Value *RHSV = B.CreateZExt(B.CreateLoad(CastToCStr(RHS, B), "rhsc"),
CI->getType(), "rhsv");
return B.CreateSub(LHSV, RHSV, "chardiff");
}
// Constant folding: memcmp(x, y, l) -> cnst (all arguments are constant)
StringRef LHSStr, RHSStr;
if (getConstantStringInfo(LHS, LHSStr) &&
getConstantStringInfo(RHS, RHSStr)) {
// Make sure we're not reading out-of-bounds memory.
if (Len > LHSStr.size() || Len > RHSStr.size())
return nullptr;
// Fold the memcmp and normalize the result. This way we get consistent
// results across multiple platforms.
uint64_t Ret = 0;
int Cmp = memcmp(LHSStr.data(), RHSStr.data(), Len);
if (Cmp < 0)
Ret = -1;
else if (Cmp > 0)
Ret = 1;
return ConstantInt::get(CI->getType(), Ret);
}
return nullptr;
}
Value *LibCallSimplifier::optimizeMemCpy(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memcpy))
return nullptr;
// memcpy(x, y, n) -> llvm.memcpy(x, y, n, 1)
B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
CI->getArgOperand(2), 1);
return CI->getArgOperand(0);
}
Value *LibCallSimplifier::optimizeMemMove(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memmove))
return nullptr;
// memmove(x, y, n) -> llvm.memmove(x, y, n, 1)
B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1),
CI->getArgOperand(2), 1);
return CI->getArgOperand(0);
}
Value *LibCallSimplifier::optimizeMemSet(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memset))
return nullptr;
// memset(p, v, n) -> llvm.memset(p, v, n, 1)
Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(), false);
B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1);
return CI->getArgOperand(0);
}
//===----------------------------------------------------------------------===//
// Math Library Optimizations
//===----------------------------------------------------------------------===//
/// Return a variant of Val with float type.
/// Currently this works in two cases: If Val is an FPExtension of a float
/// value to something bigger, simply return the operand.
/// If Val is a ConstantFP but can be converted to a float ConstantFP without
/// loss of precision do so.
static Value *valueHasFloatPrecision(Value *Val) {
if (FPExtInst *Cast = dyn_cast<FPExtInst>(Val)) {
Value *Op = Cast->getOperand(0);
if (Op->getType()->isFloatTy())
return Op;
}
if (ConstantFP *Const = dyn_cast<ConstantFP>(Val)) {
APFloat F = Const->getValueAPF();
bool losesInfo;
(void)F.convert(APFloat::IEEEsingle, APFloat::rmNearestTiesToEven,
&losesInfo);
if (!losesInfo)
return ConstantFP::get(Const->getContext(), F);
}
return nullptr;
}
//===----------------------------------------------------------------------===//
// Double -> Float Shrinking Optimizations for Unary Functions like 'floor'
Value *LibCallSimplifier::optimizeUnaryDoubleFP(CallInst *CI, IRBuilder<> &B,
bool CheckRetType) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 1 || !FT->getReturnType()->isDoubleTy() ||
!FT->getParamType(0)->isDoubleTy())
return nullptr;
if (CheckRetType) {
// Check if all the uses for function like 'sin' are converted to float.
for (User *U : CI->users()) {
FPTruncInst *Cast = dyn_cast<FPTruncInst>(U);
if (!Cast || !Cast->getType()->isFloatTy())
return nullptr;
}
}
// If this is something like 'floor((double)floatval)', convert to floorf.
Value *V = valueHasFloatPrecision(CI->getArgOperand(0));
if (V == nullptr)
return nullptr;
// floor((double)floatval) -> (double)floorf(floatval)
if (Callee->isIntrinsic()) {
Module *M = CI->getParent()->getParent()->getParent();
Intrinsic::ID IID = Callee->getIntrinsicID();
Function *F = Intrinsic::getDeclaration(M, IID, B.getFloatTy());
V = B.CreateCall(F, V);
} else {
// The call is a library call rather than an intrinsic.
V = EmitUnaryFloatFnCall(V, Callee->getName(), B, Callee->getAttributes());
}
return B.CreateFPExt(V, B.getDoubleTy());
}
// Double -> Float Shrinking Optimizations for Binary Functions like 'fmin/fmax'
Value *LibCallSimplifier::optimizeBinaryDoubleFP(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
// Just make sure this has 2 arguments of the same FP type, which match the
// result type.
if (FT->getNumParams() != 2 || FT->getReturnType() != FT->getParamType(0) ||
FT->getParamType(0) != FT->getParamType(1) ||
!FT->getParamType(0)->isFloatingPointTy())
return nullptr;
// If this is something like 'fmin((double)floatval1, (double)floatval2)',
// or fmin(1.0, (double)floatval), then we convert it to fminf.
Value *V1 = valueHasFloatPrecision(CI->getArgOperand(0));
if (V1 == nullptr)
return nullptr;
Value *V2 = valueHasFloatPrecision(CI->getArgOperand(1));
if (V2 == nullptr)
return nullptr;
// fmin((double)floatval1, (double)floatval2)
// -> (double)fminf(floatval1, floatval2)
// TODO: Handle intrinsics in the same way as in optimizeUnaryDoubleFP().
Value *V = EmitBinaryFloatFnCall(V1, V2, Callee->getName(), B,
Callee->getAttributes());
return B.CreateFPExt(V, B.getDoubleTy());
}
Value *LibCallSimplifier::optimizeCos(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
Value *Ret = nullptr;
if (UnsafeFPShrink && Callee->getName() == "cos" && TLI->has(LibFunc::cosf)) {
Ret = optimizeUnaryDoubleFP(CI, B, true);
}
FunctionType *FT = Callee->getFunctionType();
// Just make sure this has 1 argument of FP type, which matches the
// result type.
if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
!FT->getParamType(0)->isFloatingPointTy())
return Ret;
// cos(-x) -> cos(x)
Value *Op1 = CI->getArgOperand(0);
if (BinaryOperator::isFNeg(Op1)) {
BinaryOperator *BinExpr = cast<BinaryOperator>(Op1);
return B.CreateCall(Callee, BinExpr->getOperand(1), "cos");
}
return Ret;
}
Value *LibCallSimplifier::optimizePow(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
Value *Ret = nullptr;
if (UnsafeFPShrink && Callee->getName() == "pow" && TLI->has(LibFunc::powf)) {
Ret = optimizeUnaryDoubleFP(CI, B, true);
}
FunctionType *FT = Callee->getFunctionType();
// Just make sure this has 2 arguments of the same FP type, which match the
// result type.
if (FT->getNumParams() != 2 || FT->getReturnType() != FT->getParamType(0) ||
FT->getParamType(0) != FT->getParamType(1) ||
!FT->getParamType(0)->isFloatingPointTy())
return Ret;
Value *Op1 = CI->getArgOperand(0), *Op2 = CI->getArgOperand(1);
if (ConstantFP *Op1C = dyn_cast<ConstantFP>(Op1)) {
// pow(1.0, x) -> 1.0
if (Op1C->isExactlyValue(1.0))
return Op1C;
// pow(2.0, x) -> exp2(x)
if (Op1C->isExactlyValue(2.0) &&
hasUnaryFloatFn(TLI, Op1->getType(), LibFunc::exp2, LibFunc::exp2f,
LibFunc::exp2l))
return EmitUnaryFloatFnCall(Op2, "exp2", B, Callee->getAttributes());
// pow(10.0, x) -> exp10(x)
if (Op1C->isExactlyValue(10.0) &&
hasUnaryFloatFn(TLI, Op1->getType(), LibFunc::exp10, LibFunc::exp10f,
LibFunc::exp10l))
return EmitUnaryFloatFnCall(Op2, TLI->getName(LibFunc::exp10), B,
Callee->getAttributes());
}
ConstantFP *Op2C = dyn_cast<ConstantFP>(Op2);
if (!Op2C)
return Ret;
if (Op2C->getValueAPF().isZero()) // pow(x, 0.0) -> 1.0
return ConstantFP::get(CI->getType(), 1.0);
if (Op2C->isExactlyValue(0.5) &&
hasUnaryFloatFn(TLI, Op2->getType(), LibFunc::sqrt, LibFunc::sqrtf,
LibFunc::sqrtl) &&
hasUnaryFloatFn(TLI, Op2->getType(), LibFunc::fabs, LibFunc::fabsf,
LibFunc::fabsl)) {
// Expand pow(x, 0.5) to (x == -infinity ? +infinity : fabs(sqrt(x))).
// This is faster than calling pow, and still handles negative zero
// and negative infinity correctly.
// TODO: In fast-math mode, this could be just sqrt(x).
// TODO: In finite-only mode, this could be just fabs(sqrt(x)).
Value *Inf = ConstantFP::getInfinity(CI->getType());
Value *NegInf = ConstantFP::getInfinity(CI->getType(), true);
Value *Sqrt = EmitUnaryFloatFnCall(Op1, "sqrt", B, Callee->getAttributes());
Value *FAbs =
EmitUnaryFloatFnCall(Sqrt, "fabs", B, Callee->getAttributes());
Value *FCmp = B.CreateFCmpOEQ(Op1, NegInf);
Value *Sel = B.CreateSelect(FCmp, Inf, FAbs);
return Sel;
}
if (Op2C->isExactlyValue(1.0)) // pow(x, 1.0) -> x
return Op1;
if (Op2C->isExactlyValue(2.0)) // pow(x, 2.0) -> x*x
return B.CreateFMul(Op1, Op1, "pow2");
if (Op2C->isExactlyValue(-1.0)) // pow(x, -1.0) -> 1.0/x
return B.CreateFDiv(ConstantFP::get(CI->getType(), 1.0), Op1, "powrecip");
return nullptr;
}
Value *LibCallSimplifier::optimizeExp2(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
Function *Caller = CI->getParent()->getParent();
Value *Ret = nullptr;
if (UnsafeFPShrink && Callee->getName() == "exp2" &&
TLI->has(LibFunc::exp2f)) {
Ret = optimizeUnaryDoubleFP(CI, B, true);
}
FunctionType *FT = Callee->getFunctionType();
// Just make sure this has 1 argument of FP type, which matches the
// result type.
if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
!FT->getParamType(0)->isFloatingPointTy())
return Ret;
Value *Op = CI->getArgOperand(0);
// Turn exp2(sitofp(x)) -> ldexp(1.0, sext(x)) if sizeof(x) <= 32
// Turn exp2(uitofp(x)) -> ldexp(1.0, zext(x)) if sizeof(x) < 32
LibFunc::Func LdExp = LibFunc::ldexpl;
if (Op->getType()->isFloatTy())
LdExp = LibFunc::ldexpf;
else if (Op->getType()->isDoubleTy())
LdExp = LibFunc::ldexp;
if (TLI->has(LdExp)) {
Value *LdExpArg = nullptr;
if (SIToFPInst *OpC = dyn_cast<SIToFPInst>(Op)) {
if (OpC->getOperand(0)->getType()->getPrimitiveSizeInBits() <= 32)
LdExpArg = B.CreateSExt(OpC->getOperand(0), B.getInt32Ty());
} else if (UIToFPInst *OpC = dyn_cast<UIToFPInst>(Op)) {
if (OpC->getOperand(0)->getType()->getPrimitiveSizeInBits() < 32)
LdExpArg = B.CreateZExt(OpC->getOperand(0), B.getInt32Ty());
}
if (LdExpArg) {
Constant *One = ConstantFP::get(CI->getContext(), APFloat(1.0f));
if (!Op->getType()->isFloatTy())
One = ConstantExpr::getFPExtend(One, Op->getType());
Module *M = Caller->getParent();
Value *Callee =
M->getOrInsertFunction(TLI->getName(LdExp), Op->getType(),
Op->getType(), B.getInt32Ty(), nullptr);
CallInst *CI = B.CreateCall(Callee, {One, LdExpArg});
if (const Function *F = dyn_cast<Function>(Callee->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
}
return Ret;
}
Value *LibCallSimplifier::optimizeFabs(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
Value *Ret = nullptr;
if (Callee->getName() == "fabs" && TLI->has(LibFunc::fabsf)) {
Ret = optimizeUnaryDoubleFP(CI, B, false);
}
FunctionType *FT = Callee->getFunctionType();
// Make sure this has 1 argument of FP type which matches the result type.
if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
!FT->getParamType(0)->isFloatingPointTy())
return Ret;
Value *Op = CI->getArgOperand(0);
if (Instruction *I = dyn_cast<Instruction>(Op)) {
// Fold fabs(x * x) -> x * x; any squared FP value must already be positive.
if (I->getOpcode() == Instruction::FMul)
if (I->getOperand(0) == I->getOperand(1))
return Op;
}
return Ret;
}
Value *LibCallSimplifier::optimizeSqrt(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
Value *Ret = nullptr;
if (TLI->has(LibFunc::sqrtf) && (Callee->getName() == "sqrt" ||
Callee->getIntrinsicID() == Intrinsic::sqrt))
Ret = optimizeUnaryDoubleFP(CI, B, true);
// FIXME: For finer-grain optimization, we need intrinsics to have the same
// fast-math flag decorations that are applied to FP instructions. For now,
// we have to rely on the function-level unsafe-fp-math attribute to do this
// optimization because there's no other way to express that the sqrt can be
// reassociated.
Function *F = CI->getParent()->getParent();
if (F->hasFnAttribute("unsafe-fp-math")) {
// Check for unsafe-fp-math = true.
Attribute Attr = F->getFnAttribute("unsafe-fp-math");
if (Attr.getValueAsString() != "true")
return Ret;
}
Value *Op = CI->getArgOperand(0);
if (Instruction *I = dyn_cast<Instruction>(Op)) {
if (I->getOpcode() == Instruction::FMul && I->hasUnsafeAlgebra()) {
// We're looking for a repeated factor in a multiplication tree,
// so we can do this fold: sqrt(x * x) -> fabs(x);
// or this fold: sqrt(x * x * y) -> fabs(x) * sqrt(y).
Value *Op0 = I->getOperand(0);
Value *Op1 = I->getOperand(1);
Value *RepeatOp = nullptr;
Value *OtherOp = nullptr;
if (Op0 == Op1) {
// Simple match: the operands of the multiply are identical.
RepeatOp = Op0;
} else {
// Look for a more complicated pattern: one of the operands is itself
// a multiply, so search for a common factor in that multiply.
// Note: We don't bother looking any deeper than this first level or for
// variations of this pattern because instcombine's visitFMUL and/or the
// reassociation pass should give us this form.
Value *OtherMul0, *OtherMul1;
if (match(Op0, m_FMul(m_Value(OtherMul0), m_Value(OtherMul1)))) {
// Pattern: sqrt((x * y) * z)
if (OtherMul0 == OtherMul1) {
// Matched: sqrt((x * x) * z)
RepeatOp = OtherMul0;
OtherOp = Op1;
}
}
}
if (RepeatOp) {
// Fast math flags for any created instructions should match the sqrt
// and multiply.
// FIXME: We're not checking the sqrt because it doesn't have
// fast-math-flags (see earlier comment).
IRBuilder<true, ConstantFolder,
IRBuilderDefaultInserter<true> >::FastMathFlagGuard Guard(B);
B.SetFastMathFlags(I->getFastMathFlags());
// If we found a repeated factor, hoist it out of the square root and
// replace it with the fabs of that factor.
Module *M = Callee->getParent();
Type *ArgType = Op->getType();
Value *Fabs = Intrinsic::getDeclaration(M, Intrinsic::fabs, ArgType);
Value *FabsCall = B.CreateCall(Fabs, RepeatOp, "fabs");
if (OtherOp) {
// If we found a non-repeated factor, we still need to get its square
// root. We then multiply that by the value that was simplified out
// of the square root calculation.
Value *Sqrt = Intrinsic::getDeclaration(M, Intrinsic::sqrt, ArgType);
Value *SqrtCall = B.CreateCall(Sqrt, OtherOp, "sqrt");
return B.CreateFMul(FabsCall, SqrtCall);
}
return FabsCall;
}
}
}
return Ret;
}
static bool isTrigLibCall(CallInst *CI);
static void insertSinCosCall(IRBuilder<> &B, Function *OrigCallee, Value *Arg,
bool UseFloat, Value *&Sin, Value *&Cos,
Value *&SinCos);
Value *LibCallSimplifier::optimizeSinCosPi(CallInst *CI, IRBuilder<> &B) {
// Make sure the prototype is as expected, otherwise the rest of the
// function is probably invalid and likely to abort.
if (!isTrigLibCall(CI))
return nullptr;
Value *Arg = CI->getArgOperand(0);
SmallVector<CallInst *, 1> SinCalls;
SmallVector<CallInst *, 1> CosCalls;
SmallVector<CallInst *, 1> SinCosCalls;
bool IsFloat = Arg->getType()->isFloatTy();
// Look for all compatible sinpi, cospi and sincospi calls with the same
// argument. If there are enough (in some sense) we can make the
// substitution.
for (User *U : Arg->users())
classifyArgUse(U, CI->getParent(), IsFloat, SinCalls, CosCalls,
SinCosCalls);
// It's only worthwhile if both sinpi and cospi are actually used.
if (SinCosCalls.empty() && (SinCalls.empty() || CosCalls.empty()))
return nullptr;
Value *Sin, *Cos, *SinCos;
insertSinCosCall(B, CI->getCalledFunction(), Arg, IsFloat, Sin, Cos, SinCos);
replaceTrigInsts(SinCalls, Sin);
replaceTrigInsts(CosCalls, Cos);
replaceTrigInsts(SinCosCalls, SinCos);
return nullptr;
}
static bool isTrigLibCall(CallInst *CI) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
// We can only hope to do anything useful if we can ignore things like errno
// and floating-point exceptions.
bool AttributesSafe =
CI->hasFnAttr(Attribute::NoUnwind) && CI->hasFnAttr(Attribute::ReadNone);
// Other than that we need float(float) or double(double)
return AttributesSafe && FT->getNumParams() == 1 &&
FT->getReturnType() == FT->getParamType(0) &&
(FT->getParamType(0)->isFloatTy() ||
FT->getParamType(0)->isDoubleTy());
}
void
LibCallSimplifier::classifyArgUse(Value *Val, BasicBlock *BB, bool IsFloat,
SmallVectorImpl<CallInst *> &SinCalls,
SmallVectorImpl<CallInst *> &CosCalls,
SmallVectorImpl<CallInst *> &SinCosCalls) {
CallInst *CI = dyn_cast<CallInst>(Val);
if (!CI)
return;
Function *Callee = CI->getCalledFunction();
StringRef FuncName = Callee->getName();
LibFunc::Func Func;
if (!TLI->getLibFunc(FuncName, Func) || !TLI->has(Func) || !isTrigLibCall(CI))
return;
if (IsFloat) {
if (Func == LibFunc::sinpif)
SinCalls.push_back(CI);
else if (Func == LibFunc::cospif)
CosCalls.push_back(CI);
else if (Func == LibFunc::sincospif_stret)
SinCosCalls.push_back(CI);
} else {
if (Func == LibFunc::sinpi)
SinCalls.push_back(CI);
else if (Func == LibFunc::cospi)
CosCalls.push_back(CI);
else if (Func == LibFunc::sincospi_stret)
SinCosCalls.push_back(CI);
}
}
void LibCallSimplifier::replaceTrigInsts(SmallVectorImpl<CallInst *> &Calls,
Value *Res) {
for (SmallVectorImpl<CallInst *>::iterator I = Calls.begin(), E = Calls.end();
I != E; ++I) {
replaceAllUsesWith(*I, Res);
}
}
void insertSinCosCall(IRBuilder<> &B, Function *OrigCallee, Value *Arg,
bool UseFloat, Value *&Sin, Value *&Cos, Value *&SinCos) {
Type *ArgTy = Arg->getType();
Type *ResTy;
StringRef Name;
Triple T(OrigCallee->getParent()->getTargetTriple());
if (UseFloat) {
Name = "__sincospif_stret";
assert(T.getArch() != Triple::x86 && "x86 messy and unsupported for now");
// x86_64 can't use {float, float} since that would be returned in both
// xmm0 and xmm1, which isn't what a real struct would do.
ResTy = T.getArch() == Triple::x86_64
? static_cast<Type *>(VectorType::get(ArgTy, 2))
: static_cast<Type *>(StructType::get(ArgTy, ArgTy, nullptr));
} else {
Name = "__sincospi_stret";
ResTy = StructType::get(ArgTy, ArgTy, nullptr);
}
Module *M = OrigCallee->getParent();
Value *Callee = M->getOrInsertFunction(Name, OrigCallee->getAttributes(),
ResTy, ArgTy, nullptr);
if (Instruction *ArgInst = dyn_cast<Instruction>(Arg)) {
// If the argument is an instruction, it must dominate all uses so put our
// sincos call there.
BasicBlock::iterator Loc = ArgInst;
B.SetInsertPoint(ArgInst->getParent(), ++Loc);
} else {
// Otherwise (e.g. for a constant) the beginning of the function is as
// good a place as any.
BasicBlock &EntryBB = B.GetInsertBlock()->getParent()->getEntryBlock();
B.SetInsertPoint(&EntryBB, EntryBB.begin());
}
SinCos = B.CreateCall(Callee, Arg, "sincospi");
if (SinCos->getType()->isStructTy()) {
Sin = B.CreateExtractValue(SinCos, 0, "sinpi");
Cos = B.CreateExtractValue(SinCos, 1, "cospi");
} else {
Sin = B.CreateExtractElement(SinCos, ConstantInt::get(B.getInt32Ty(), 0),
"sinpi");
Cos = B.CreateExtractElement(SinCos, ConstantInt::get(B.getInt32Ty(), 1),
"cospi");
}
}
//===----------------------------------------------------------------------===//
// Integer Library Call Optimizations
//===----------------------------------------------------------------------===//
Value *LibCallSimplifier::optimizeFFS(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
// Just make sure this has 2 arguments of the same FP type, which match the
// result type.
if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy(32) ||
!FT->getParamType(0)->isIntegerTy())
return nullptr;
Value *Op = CI->getArgOperand(0);
// Constant fold.
if (ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
if (CI->isZero()) // ffs(0) -> 0.
return B.getInt32(0);
// ffs(c) -> cttz(c)+1
return B.getInt32(CI->getValue().countTrailingZeros() + 1);
}
// ffs(x) -> x != 0 ? (i32)llvm.cttz(x)+1 : 0
Type *ArgType = Op->getType();
Value *F =
Intrinsic::getDeclaration(Callee->getParent(), Intrinsic::cttz, ArgType);
Value *V = B.CreateCall(F, {Op, B.getFalse()}, "cttz");
V = B.CreateAdd(V, ConstantInt::get(V->getType(), 1));
V = B.CreateIntCast(V, B.getInt32Ty(), false);
Value *Cond = B.CreateICmpNE(Op, Constant::getNullValue(ArgType));
return B.CreateSelect(Cond, V, B.getInt32(0));
}
Value *LibCallSimplifier::optimizeAbs(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
// We require integer(integer) where the types agree.
if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
FT->getParamType(0) != FT->getReturnType())
return nullptr;
// abs(x) -> x >s -1 ? x : -x
Value *Op = CI->getArgOperand(0);
Value *Pos =
B.CreateICmpSGT(Op, Constant::getAllOnesValue(Op->getType()), "ispos");
Value *Neg = B.CreateNeg(Op, "neg");
return B.CreateSelect(Pos, Op, Neg);
}
Value *LibCallSimplifier::optimizeIsDigit(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
// We require integer(i32)
if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
!FT->getParamType(0)->isIntegerTy(32))
return nullptr;
// isdigit(c) -> (c-'0') <u 10
Value *Op = CI->getArgOperand(0);
Op = B.CreateSub(Op, B.getInt32('0'), "isdigittmp");
Op = B.CreateICmpULT(Op, B.getInt32(10), "isdigit");
return B.CreateZExt(Op, CI->getType());
}
Value *LibCallSimplifier::optimizeIsAscii(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
// We require integer(i32)
if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
!FT->getParamType(0)->isIntegerTy(32))
return nullptr;
// isascii(c) -> c <u 128
Value *Op = CI->getArgOperand(0);
Op = B.CreateICmpULT(Op, B.getInt32(128), "isascii");
return B.CreateZExt(Op, CI->getType());
}
Value *LibCallSimplifier::optimizeToAscii(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
FunctionType *FT = Callee->getFunctionType();
// We require i32(i32)
if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
!FT->getParamType(0)->isIntegerTy(32))
return nullptr;
// toascii(c) -> c & 0x7f
return B.CreateAnd(CI->getArgOperand(0),
ConstantInt::get(CI->getType(), 0x7F));
}
//===----------------------------------------------------------------------===//
// Formatting and IO Library Call Optimizations
//===----------------------------------------------------------------------===//
static bool isReportingError(Function *Callee, CallInst *CI, int StreamArg);
Value *LibCallSimplifier::optimizeErrorReporting(CallInst *CI, IRBuilder<> &B,
int StreamArg) {
// Error reporting calls should be cold, mark them as such.
// This applies even to non-builtin calls: it is only a hint and applies to
// functions that the frontend might not understand as builtins.
// This heuristic was suggested in:
// Improving Static Branch Prediction in a Compiler
// Brian L. Deitrich, Ben-Chung Cheng, Wen-mei W. Hwu
// Proceedings of PACT'98, Oct. 1998, IEEE
Function *Callee = CI->getCalledFunction();
if (!CI->hasFnAttr(Attribute::Cold) &&
isReportingError(Callee, CI, StreamArg)) {
CI->addAttribute(AttributeSet::FunctionIndex, Attribute::Cold);
}
return nullptr;
}
static bool isReportingError(Function *Callee, CallInst *CI, int StreamArg) {
if (!ColdErrorCalls)
return false;
if (!Callee || !Callee->isDeclaration())
return false;
if (StreamArg < 0)
return true;
// These functions might be considered cold, but only if their stream
// argument is stderr.
if (StreamArg >= (int)CI->getNumArgOperands())
return false;
LoadInst *LI = dyn_cast<LoadInst>(CI->getArgOperand(StreamArg));
if (!LI)
return false;
GlobalVariable *GV = dyn_cast<GlobalVariable>(LI->getPointerOperand());
if (!GV || !GV->isDeclaration())
return false;
return GV->getName() == "stderr";
}
Value *LibCallSimplifier::optimizePrintFString(CallInst *CI, IRBuilder<> &B) {
// Check for a fixed format string.
StringRef FormatStr;
if (!getConstantStringInfo(CI->getArgOperand(0), FormatStr))
return nullptr;
// Empty format string -> noop.
if (FormatStr.empty()) // Tolerate printf's declared void.
return CI->use_empty() ? (Value *)CI : ConstantInt::get(CI->getType(), 0);
// Do not do any of the following transformations if the printf return value
// is used, in general the printf return value is not compatible with either
// putchar() or puts().
if (!CI->use_empty())
return nullptr;
// printf("x") -> putchar('x'), even for '%'.
if (FormatStr.size() == 1) {
Value *Res = EmitPutChar(B.getInt32(FormatStr[0]), B, TLI);
if (CI->use_empty() || !Res)
return Res;
return B.CreateIntCast(Res, CI->getType(), true);
}
// printf("foo\n") --> puts("foo")
if (FormatStr[FormatStr.size() - 1] == '\n' &&
FormatStr.find('%') == StringRef::npos) { // No format characters.
// Create a string literal with no \n on it. We expect the constant merge
// pass to be run after this pass, to merge duplicate strings.
FormatStr = FormatStr.drop_back();
Value *GV = B.CreateGlobalString(FormatStr, "str");
Value *NewCI = EmitPutS(GV, B, TLI);
return (CI->use_empty() || !NewCI)
? NewCI
: ConstantInt::get(CI->getType(), FormatStr.size() + 1);
}
// Optimize specific format strings.
// printf("%c", chr) --> putchar(chr)
if (FormatStr == "%c" && CI->getNumArgOperands() > 1 &&
CI->getArgOperand(1)->getType()->isIntegerTy()) {
Value *Res = EmitPutChar(CI->getArgOperand(1), B, TLI);
if (CI->use_empty() || !Res)
return Res;
return B.CreateIntCast(Res, CI->getType(), true);
}
// printf("%s\n", str) --> puts(str)
if (FormatStr == "%s\n" && CI->getNumArgOperands() > 1 &&
CI->getArgOperand(1)->getType()->isPointerTy()) {
return EmitPutS(CI->getArgOperand(1), B, TLI);
}
return nullptr;
}
Value *LibCallSimplifier::optimizePrintF(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
// Require one fixed pointer argument and an integer/void result.
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
!(FT->getReturnType()->isIntegerTy() || FT->getReturnType()->isVoidTy()))
return nullptr;
if (Value *V = optimizePrintFString(CI, B)) {
return V;
}
// printf(format, ...) -> iprintf(format, ...) if no floating point
// arguments.
if (TLI->has(LibFunc::iprintf) && !callHasFloatingPointArgument(CI)) {
Module *M = B.GetInsertBlock()->getParent()->getParent();
Constant *IPrintFFn =
M->getOrInsertFunction("iprintf", FT, Callee->getAttributes());
CallInst *New = cast<CallInst>(CI->clone());
New->setCalledFunction(IPrintFFn);
B.Insert(New);
return New;
}
return nullptr;
}
Value *LibCallSimplifier::optimizeSPrintFString(CallInst *CI, IRBuilder<> &B) {
// Check for a fixed format string.
StringRef FormatStr;
if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
return nullptr;
// If we just have a format string (nothing else crazy) transform it.
if (CI->getNumArgOperands() == 2) {
// Make sure there's no % in the constant array. We could try to handle
// %% -> % in the future if we cared.
for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
if (FormatStr[i] == '%')
return nullptr; // we found a format specifier, bail out.
// sprintf(str, fmt) -> llvm.memcpy(str, fmt, strlen(fmt)+1, 1)
B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
ConstantInt::get(DL.getIntPtrType(CI->getContext()),
FormatStr.size() + 1),
1); // Copy the null byte.
return ConstantInt::get(CI->getType(), FormatStr.size());
}
// The remaining optimizations require the format string to be "%s" or "%c"
// and have an extra operand.
if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
CI->getNumArgOperands() < 3)
return nullptr;
// Decode the second character of the format string.
if (FormatStr[1] == 'c') {
// sprintf(dst, "%c", chr) --> *(i8*)dst = chr; *((i8*)dst+1) = 0
if (!CI->getArgOperand(2)->getType()->isIntegerTy())
return nullptr;
Value *V = B.CreateTrunc(CI->getArgOperand(2), B.getInt8Ty(), "char");
Value *Ptr = CastToCStr(CI->getArgOperand(0), B);
B.CreateStore(V, Ptr);
Ptr = B.CreateGEP(B.getInt8Ty(), Ptr, B.getInt32(1), "nul");
B.CreateStore(B.getInt8(0), Ptr);
return ConstantInt::get(CI->getType(), 1);
}
if (FormatStr[1] == 's') {
// sprintf(dest, "%s", str) -> llvm.memcpy(dest, str, strlen(str)+1, 1)
if (!CI->getArgOperand(2)->getType()->isPointerTy())
return nullptr;
Value *Len = EmitStrLen(CI->getArgOperand(2), B, DL, TLI);
if (!Len)
return nullptr;
Value *IncLen =
B.CreateAdd(Len, ConstantInt::get(Len->getType(), 1), "leninc");
B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(2), IncLen, 1);
// The sprintf result is the unincremented number of bytes in the string.
return B.CreateIntCast(Len, CI->getType(), false);
}
return nullptr;
}
Value *LibCallSimplifier::optimizeSPrintF(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
// Require two fixed pointer arguments and an integer result.
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
!FT->getParamType(1)->isPointerTy() ||
!FT->getReturnType()->isIntegerTy())
return nullptr;
if (Value *V = optimizeSPrintFString(CI, B)) {
return V;
}
// sprintf(str, format, ...) -> siprintf(str, format, ...) if no floating
// point arguments.
if (TLI->has(LibFunc::siprintf) && !callHasFloatingPointArgument(CI)) {
Module *M = B.GetInsertBlock()->getParent()->getParent();
Constant *SIPrintFFn =
M->getOrInsertFunction("siprintf", FT, Callee->getAttributes());
CallInst *New = cast<CallInst>(CI->clone());
New->setCalledFunction(SIPrintFFn);
B.Insert(New);
return New;
}
return nullptr;
}
Value *LibCallSimplifier::optimizeFPrintFString(CallInst *CI, IRBuilder<> &B) {
optimizeErrorReporting(CI, B, 0);
// All the optimizations depend on the format string.
StringRef FormatStr;
if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
return nullptr;
// Do not do any of the following transformations if the fprintf return
// value is used, in general the fprintf return value is not compatible
// with fwrite(), fputc() or fputs().
if (!CI->use_empty())
return nullptr;
// fprintf(F, "foo") --> fwrite("foo", 3, 1, F)
if (CI->getNumArgOperands() == 2) {
for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
if (FormatStr[i] == '%') // Could handle %% -> % if we cared.
return nullptr; // We found a format specifier.
return EmitFWrite(
CI->getArgOperand(1),
ConstantInt::get(DL.getIntPtrType(CI->getContext()), FormatStr.size()),
CI->getArgOperand(0), B, DL, TLI);
}
// The remaining optimizations require the format string to be "%s" or "%c"
// and have an extra operand.
if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
CI->getNumArgOperands() < 3)
return nullptr;
// Decode the second character of the format string.
if (FormatStr[1] == 'c') {
// fprintf(F, "%c", chr) --> fputc(chr, F)
if (!CI->getArgOperand(2)->getType()->isIntegerTy())
return nullptr;
return EmitFPutC(CI->getArgOperand(2), CI->getArgOperand(0), B, TLI);
}
if (FormatStr[1] == 's') {
// fprintf(F, "%s", str) --> fputs(str, F)
if (!CI->getArgOperand(2)->getType()->isPointerTy())
return nullptr;
return EmitFPutS(CI->getArgOperand(2), CI->getArgOperand(0), B, TLI);
}
return nullptr;
}
Value *LibCallSimplifier::optimizeFPrintF(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
// Require two fixed paramters as pointers and integer result.
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
!FT->getParamType(1)->isPointerTy() ||
!FT->getReturnType()->isIntegerTy())
return nullptr;
if (Value *V = optimizeFPrintFString(CI, B)) {
return V;
}
// fprintf(stream, format, ...) -> fiprintf(stream, format, ...) if no
// floating point arguments.
if (TLI->has(LibFunc::fiprintf) && !callHasFloatingPointArgument(CI)) {
Module *M = B.GetInsertBlock()->getParent()->getParent();
Constant *FIPrintFFn =
M->getOrInsertFunction("fiprintf", FT, Callee->getAttributes());
CallInst *New = cast<CallInst>(CI->clone());
New->setCalledFunction(FIPrintFFn);
B.Insert(New);
return New;
}
return nullptr;
}
Value *LibCallSimplifier::optimizeFWrite(CallInst *CI, IRBuilder<> &B) {
optimizeErrorReporting(CI, B, 3);
Function *Callee = CI->getCalledFunction();
// Require a pointer, an integer, an integer, a pointer, returning integer.
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 4 || !FT->getParamType(0)->isPointerTy() ||
!FT->getParamType(1)->isIntegerTy() ||
!FT->getParamType(2)->isIntegerTy() ||
!FT->getParamType(3)->isPointerTy() ||
!FT->getReturnType()->isIntegerTy())
return nullptr;
// Get the element size and count.
ConstantInt *SizeC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
ConstantInt *CountC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
if (!SizeC || !CountC)
return nullptr;
uint64_t Bytes = SizeC->getZExtValue() * CountC->getZExtValue();
// If this is writing zero records, remove the call (it's a noop).
if (Bytes == 0)
return ConstantInt::get(CI->getType(), 0);
// If this is writing one byte, turn it into fputc.
// This optimisation is only valid, if the return value is unused.
if (Bytes == 1 && CI->use_empty()) { // fwrite(S,1,1,F) -> fputc(S[0],F)
Value *Char = B.CreateLoad(CastToCStr(CI->getArgOperand(0), B), "char");
Value *NewCI = EmitFPutC(Char, CI->getArgOperand(3), B, TLI);
return NewCI ? ConstantInt::get(CI->getType(), 1) : nullptr;
}
return nullptr;
}
Value *LibCallSimplifier::optimizeFPuts(CallInst *CI, IRBuilder<> &B) {
optimizeErrorReporting(CI, B, 1);
Function *Callee = CI->getCalledFunction();
// Require two pointers. Also, we can't optimize if return value is used.
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
!FT->getParamType(1)->isPointerTy() || !CI->use_empty())
return nullptr;
// fputs(s,F) --> fwrite(s,1,strlen(s),F)
uint64_t Len = GetStringLength(CI->getArgOperand(0));
if (!Len)
return nullptr;
// Known to have no uses (see above).
return EmitFWrite(
CI->getArgOperand(0),
ConstantInt::get(DL.getIntPtrType(CI->getContext()), Len - 1),
CI->getArgOperand(1), B, DL, TLI);
}
Value *LibCallSimplifier::optimizePuts(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
// Require one fixed pointer argument and an integer/void result.
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
!(FT->getReturnType()->isIntegerTy() || FT->getReturnType()->isVoidTy()))
return nullptr;
// Check for a constant string.
StringRef Str;
if (!getConstantStringInfo(CI->getArgOperand(0), Str))
return nullptr;
if (Str.empty() && CI->use_empty()) {
// puts("") -> putchar('\n')
Value *Res = EmitPutChar(B.getInt32('\n'), B, TLI);
if (CI->use_empty() || !Res)
return Res;
return B.CreateIntCast(Res, CI->getType(), true);
}
return nullptr;
}
bool LibCallSimplifier::hasFloatVersion(StringRef FuncName) {
LibFunc::Func Func;
SmallString<20> FloatFuncName = FuncName;
FloatFuncName += 'f';
if (TLI->getLibFunc(FloatFuncName, Func))
return TLI->has(Func);
return false;
}
Value *LibCallSimplifier::optimizeStringMemoryLibCall(CallInst *CI,
IRBuilder<> &Builder) {
LibFunc::Func Func;
Function *Callee = CI->getCalledFunction();
StringRef FuncName = Callee->getName();
// Check for string/memory library functions.
if (TLI->getLibFunc(FuncName, Func) && TLI->has(Func)) {
// Make sure we never change the calling convention.
assert((ignoreCallingConv(Func) ||
CI->getCallingConv() == llvm::CallingConv::C) &&
"Optimizing string/memory libcall would change the calling convention");
switch (Func) {
case LibFunc::strcat:
return optimizeStrCat(CI, Builder);
case LibFunc::strncat:
return optimizeStrNCat(CI, Builder);
case LibFunc::strchr:
return optimizeStrChr(CI, Builder);
case LibFunc::strrchr:
return optimizeStrRChr(CI, Builder);
case LibFunc::strcmp:
return optimizeStrCmp(CI, Builder);
case LibFunc::strncmp:
return optimizeStrNCmp(CI, Builder);
case LibFunc::strcpy:
return optimizeStrCpy(CI, Builder);
case LibFunc::stpcpy:
return optimizeStpCpy(CI, Builder);
case LibFunc::strncpy:
return optimizeStrNCpy(CI, Builder);
case LibFunc::strlen:
return optimizeStrLen(CI, Builder);
case LibFunc::strpbrk:
return optimizeStrPBrk(CI, Builder);
case LibFunc::strtol:
case LibFunc::strtod:
case LibFunc::strtof:
case LibFunc::strtoul:
case LibFunc::strtoll:
case LibFunc::strtold:
case LibFunc::strtoull:
return optimizeStrTo(CI, Builder);
case LibFunc::strspn:
return optimizeStrSpn(CI, Builder);
case LibFunc::strcspn:
return optimizeStrCSpn(CI, Builder);
case LibFunc::strstr:
return optimizeStrStr(CI, Builder);
case LibFunc::memchr:
return optimizeMemChr(CI, Builder);
case LibFunc::memcmp:
return optimizeMemCmp(CI, Builder);
case LibFunc::memcpy:
return optimizeMemCpy(CI, Builder);
case LibFunc::memmove:
return optimizeMemMove(CI, Builder);
case LibFunc::memset:
return optimizeMemSet(CI, Builder);
default:
break;
}
}
return nullptr;
}
Value *LibCallSimplifier::optimizeCall(CallInst *CI) {
if (CI->isNoBuiltin())
return nullptr;
LibFunc::Func Func;
Function *Callee = CI->getCalledFunction();
StringRef FuncName = Callee->getName();
IRBuilder<> Builder(CI);
bool isCallingConvC = CI->getCallingConv() == llvm::CallingConv::C;
// Command-line parameter overrides function attribute.
if (false) // HLSL Change - EnableUnsafeFPShrink.getNumOccurrences() > 0)
UnsafeFPShrink = EnableUnsafeFPShrink;
else if (Callee->hasFnAttribute("unsafe-fp-math")) {
// FIXME: This is the same problem as described in optimizeSqrt().
// If calls gain access to IR-level FMF, then use that instead of a
// function attribute.
// Check for unsafe-fp-math = true.
Attribute Attr = Callee->getFnAttribute("unsafe-fp-math");
if (Attr.getValueAsString() == "true")
UnsafeFPShrink = true;
}
// First, check for intrinsics.
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI)) {
if (!isCallingConvC)
return nullptr;
switch (II->getIntrinsicID()) {
case Intrinsic::pow:
return optimizePow(CI, Builder);
case Intrinsic::exp2:
return optimizeExp2(CI, Builder);
case Intrinsic::fabs:
return optimizeFabs(CI, Builder);
case Intrinsic::sqrt:
return optimizeSqrt(CI, Builder);
default:
return nullptr;
}
}
// Also try to simplify calls to fortified library functions.
if (Value *SimplifiedFortifiedCI = FortifiedSimplifier.optimizeCall(CI)) {
// Try to further simplify the result.
CallInst *SimplifiedCI = dyn_cast<CallInst>(SimplifiedFortifiedCI);
if (SimplifiedCI && SimplifiedCI->getCalledFunction())
if (Value *V = optimizeStringMemoryLibCall(SimplifiedCI, Builder)) {
// If we were able to further simplify, remove the now redundant call.
SimplifiedCI->replaceAllUsesWith(V);
SimplifiedCI->eraseFromParent();
return V;
}
return SimplifiedFortifiedCI;
}
// Then check for known library functions.
if (TLI->getLibFunc(FuncName, Func) && TLI->has(Func)) {
// We never change the calling convention.
if (!ignoreCallingConv(Func) && !isCallingConvC)
return nullptr;
if (Value *V = optimizeStringMemoryLibCall(CI, Builder))
return V;
switch (Func) {
case LibFunc::cosf:
case LibFunc::cos:
case LibFunc::cosl:
return optimizeCos(CI, Builder);
case LibFunc::sinpif:
case LibFunc::sinpi:
case LibFunc::cospif:
case LibFunc::cospi:
return optimizeSinCosPi(CI, Builder);
case LibFunc::powf:
case LibFunc::pow:
case LibFunc::powl:
return optimizePow(CI, Builder);
case LibFunc::exp2l:
case LibFunc::exp2:
case LibFunc::exp2f:
return optimizeExp2(CI, Builder);
case LibFunc::fabsf:
case LibFunc::fabs:
case LibFunc::fabsl:
return optimizeFabs(CI, Builder);
case LibFunc::sqrtf:
case LibFunc::sqrt:
case LibFunc::sqrtl:
return optimizeSqrt(CI, Builder);
case LibFunc::ffs:
case LibFunc::ffsl:
case LibFunc::ffsll:
return optimizeFFS(CI, Builder);
case LibFunc::abs:
case LibFunc::labs:
case LibFunc::llabs:
return optimizeAbs(CI, Builder);
case LibFunc::isdigit:
return optimizeIsDigit(CI, Builder);
case LibFunc::isascii:
return optimizeIsAscii(CI, Builder);
case LibFunc::toascii:
return optimizeToAscii(CI, Builder);
case LibFunc::printf:
return optimizePrintF(CI, Builder);
case LibFunc::sprintf:
return optimizeSPrintF(CI, Builder);
case LibFunc::fprintf:
return optimizeFPrintF(CI, Builder);
case LibFunc::fwrite:
return optimizeFWrite(CI, Builder);
case LibFunc::fputs:
return optimizeFPuts(CI, Builder);
case LibFunc::puts:
return optimizePuts(CI, Builder);
case LibFunc::perror:
return optimizeErrorReporting(CI, Builder);
case LibFunc::vfprintf:
case LibFunc::fiprintf:
return optimizeErrorReporting(CI, Builder, 0);
case LibFunc::fputc:
return optimizeErrorReporting(CI, Builder, 1);
case LibFunc::ceil:
case LibFunc::floor:
case LibFunc::rint:
case LibFunc::round:
case LibFunc::nearbyint:
case LibFunc::trunc:
if (hasFloatVersion(FuncName))
return optimizeUnaryDoubleFP(CI, Builder, false);
return nullptr;
case LibFunc::acos:
case LibFunc::acosh:
case LibFunc::asin:
case LibFunc::asinh:
case LibFunc::atan:
case LibFunc::atanh:
case LibFunc::cbrt:
case LibFunc::cosh:
case LibFunc::exp:
case LibFunc::exp10:
case LibFunc::expm1:
case LibFunc::log:
case LibFunc::log10:
case LibFunc::log1p:
case LibFunc::log2:
case LibFunc::logb:
case LibFunc::sin:
case LibFunc::sinh:
case LibFunc::tan:
case LibFunc::tanh:
if (UnsafeFPShrink && hasFloatVersion(FuncName))
return optimizeUnaryDoubleFP(CI, Builder, true);
return nullptr;
case LibFunc::copysign:
case LibFunc::fmin:
case LibFunc::fmax:
if (hasFloatVersion(FuncName))
return optimizeBinaryDoubleFP(CI, Builder);
return nullptr;
default:
return nullptr;
}
}
return nullptr;
}
LibCallSimplifier::LibCallSimplifier(
const DataLayout &DL, const TargetLibraryInfo *TLI,
function_ref<void(Instruction *, Value *)> Replacer)
: FortifiedSimplifier(TLI), DL(DL), TLI(TLI), UnsafeFPShrink(false),
Replacer(Replacer) {}
void LibCallSimplifier::replaceAllUsesWith(Instruction *I, Value *With) {
// Indirect through the replacer used in this instance.
Replacer(I, With);
}
/*static*/ void LibCallSimplifier::replaceAllUsesWithDefault(Instruction *I,
Value *With) {
I->replaceAllUsesWith(With);
I->eraseFromParent();
}
// TODO:
// Additional cases that we need to add to this file:
//
// cbrt:
// * cbrt(expN(X)) -> expN(x/3)
// * cbrt(sqrt(x)) -> pow(x,1/6)
// * cbrt(sqrt(x)) -> pow(x,1/9)
//
// exp, expf, expl:
// * exp(log(x)) -> x
//
// log, logf, logl:
// * log(exp(x)) -> x
// * log(x**y) -> y*log(x)
// * log(exp(y)) -> y*log(e)
// * log(exp2(y)) -> y*log(2)
// * log(exp10(y)) -> y*log(10)
// * log(sqrt(x)) -> 0.5*log(x)
// * log(pow(x,y)) -> y*log(x)
//
// lround, lroundf, lroundl:
// * lround(cnst) -> cnst'
//
// pow, powf, powl:
// * pow(exp(x),y) -> exp(x*y)
// * pow(sqrt(x),y) -> pow(x,y*0.5)
// * pow(pow(x,y),z)-> pow(x,y*z)
//
// round, roundf, roundl:
// * round(cnst) -> cnst'
//
// signbit:
// * signbit(cnst) -> cnst'
// * signbit(nncst) -> 0 (if pstv is a non-negative constant)
//
// sqrt, sqrtf, sqrtl:
// * sqrt(expN(x)) -> expN(x*0.5)
// * sqrt(Nroot(x)) -> pow(x,1/(2*N))
// * sqrt(pow(x,y)) -> pow(|x|,y*0.5)
//
// tan, tanf, tanl:
// * tan(atan(x)) -> x
//
// trunc, truncf, truncl:
// * trunc(cnst) -> cnst'
//
//
//===----------------------------------------------------------------------===//
// Fortified Library Call Optimizations
//===----------------------------------------------------------------------===//
bool FortifiedLibCallSimplifier::isFortifiedCallFoldable(CallInst *CI,
unsigned ObjSizeOp,
unsigned SizeOp,
bool isString) {
if (CI->getArgOperand(ObjSizeOp) == CI->getArgOperand(SizeOp))
return true;
if (ConstantInt *ObjSizeCI =
dyn_cast<ConstantInt>(CI->getArgOperand(ObjSizeOp))) {
if (ObjSizeCI->isAllOnesValue())
return true;
// If the object size wasn't -1 (unknown), bail out if we were asked to.
if (OnlyLowerUnknownSize)
return false;
if (isString) {
uint64_t Len = GetStringLength(CI->getArgOperand(SizeOp));
// If the length is 0 we don't know how long it is and so we can't
// remove the check.
if (Len == 0)
return false;
return ObjSizeCI->getZExtValue() >= Len;
}
if (ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getArgOperand(SizeOp)))
return ObjSizeCI->getZExtValue() >= SizeCI->getZExtValue();
}
return false;
}
Value *FortifiedLibCallSimplifier::optimizeMemCpyChk(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memcpy_chk))
return nullptr;
if (isFortifiedCallFoldable(CI, 3, 2, false)) {
B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
CI->getArgOperand(2), 1);
return CI->getArgOperand(0);
}
return nullptr;
}
Value *FortifiedLibCallSimplifier::optimizeMemMoveChk(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memmove_chk))
return nullptr;
if (isFortifiedCallFoldable(CI, 3, 2, false)) {
B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1),
CI->getArgOperand(2), 1);
return CI->getArgOperand(0);
}
return nullptr;
}
Value *FortifiedLibCallSimplifier::optimizeMemSetChk(CallInst *CI, IRBuilder<> &B) {
Function *Callee = CI->getCalledFunction();
if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memset_chk))
return nullptr;
if (isFortifiedCallFoldable(CI, 3, 2, false)) {
Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(), false);
B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1);
return CI->getArgOperand(0);
}
return nullptr;
}
Value *FortifiedLibCallSimplifier::optimizeStrpCpyChk(CallInst *CI,
IRBuilder<> &B,
LibFunc::Func Func) {
Function *Callee = CI->getCalledFunction();
StringRef Name = Callee->getName();
const DataLayout &DL = CI->getModule()->getDataLayout();
if (!checkStringCopyLibFuncSignature(Callee, Func))
return nullptr;
Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1),
*ObjSize = CI->getArgOperand(2);
// __stpcpy_chk(x,x,...) -> x+strlen(x)
if (Func == LibFunc::stpcpy_chk && !OnlyLowerUnknownSize && Dst == Src) {
Value *StrLen = EmitStrLen(Src, B, DL, TLI);
return StrLen ? B.CreateInBoundsGEP(B.getInt8Ty(), Dst, StrLen) : nullptr;
}
// If a) we don't have any length information, or b) we know this will
// fit then just lower to a plain st[rp]cpy. Otherwise we'll keep our
// st[rp]cpy_chk call which may fail at runtime if the size is too long.
// TODO: It might be nice to get a maximum length out of the possible
// string lengths for varying.
if (isFortifiedCallFoldable(CI, 2, 1, true))
return EmitStrCpy(Dst, Src, B, TLI, Name.substr(2, 6));
if (OnlyLowerUnknownSize)
return nullptr;
// Maybe we can stil fold __st[rp]cpy_chk to __memcpy_chk.
uint64_t Len = GetStringLength(Src);
if (Len == 0)
return nullptr;
Type *SizeTTy = DL.getIntPtrType(CI->getContext());
Value *LenV = ConstantInt::get(SizeTTy, Len);
Value *Ret = EmitMemCpyChk(Dst, Src, LenV, ObjSize, B, DL, TLI);
// If the function was an __stpcpy_chk, and we were able to fold it into
// a __memcpy_chk, we still need to return the correct end pointer.
if (Ret && Func == LibFunc::stpcpy_chk)
return B.CreateGEP(B.getInt8Ty(), Dst, ConstantInt::get(SizeTTy, Len - 1));
return Ret;
}
Value *FortifiedLibCallSimplifier::optimizeStrpNCpyChk(CallInst *CI,
IRBuilder<> &B,
LibFunc::Func Func) {
Function *Callee = CI->getCalledFunction();
StringRef Name = Callee->getName();
if (!checkStringCopyLibFuncSignature(Callee, Func))
return nullptr;
if (isFortifiedCallFoldable(CI, 3, 2, false)) {
Value *Ret = EmitStrNCpy(CI->getArgOperand(0), CI->getArgOperand(1),
CI->getArgOperand(2), B, TLI, Name.substr(2, 7));
return Ret;
}
return nullptr;
}
Value *FortifiedLibCallSimplifier::optimizeCall(CallInst *CI) {
// FIXME: We shouldn't be changing "nobuiltin" or TLI unavailable calls here.
// Some clang users checked for _chk libcall availability using:
// __has_builtin(__builtin___memcpy_chk)
// When compiling with -fno-builtin, this is always true.
// When passing -ffreestanding/-mkernel, which both imply -fno-builtin, we
// end up with fortified libcalls, which isn't acceptable in a freestanding
// environment which only provides their non-fortified counterparts.
//
// Until we change clang and/or teach external users to check for availability
// differently, disregard the "nobuiltin" attribute and TLI::has.
//
// PR23093.
LibFunc::Func Func;
Function *Callee = CI->getCalledFunction();
StringRef FuncName = Callee->getName();
IRBuilder<> Builder(CI);
bool isCallingConvC = CI->getCallingConv() == llvm::CallingConv::C;
// First, check that this is a known library functions.
if (!TLI->getLibFunc(FuncName, Func))
return nullptr;
// We never change the calling convention.
if (!ignoreCallingConv(Func) && !isCallingConvC)
return nullptr;
switch (Func) {
case LibFunc::memcpy_chk:
return optimizeMemCpyChk(CI, Builder);
case LibFunc::memmove_chk:
return optimizeMemMoveChk(CI, Builder);
case LibFunc::memset_chk:
return optimizeMemSetChk(CI, Builder);
case LibFunc::stpcpy_chk:
case LibFunc::strcpy_chk:
return optimizeStrpCpyChk(CI, Builder, Func);
case LibFunc::stpncpy_chk:
case LibFunc::strncpy_chk:
return optimizeStrpNCpyChk(CI, Builder, Func);
default:
break;
}
return nullptr;
}
FortifiedLibCallSimplifier::FortifiedLibCallSimplifier(
const TargetLibraryInfo *TLI, bool OnlyLowerUnknownSize)
: TLI(TLI), OnlyLowerUnknownSize(OnlyLowerUnknownSize) {}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/LoopSimplifyId.cpp | //===- LoopSimplifyId.cpp - ID for the Loop Canonicalization Pass
//----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Pass.h"
#include "llvm/Transforms/Utils/LoopSimplify.h"
using namespace llvm;
char LoopSimplify::ID = 0;
// Publicly exposed interface to pass...
// This is in a separate file instead of LoopSimplify.cpp which brings in many
// dependencies unnecessary increasing the size of dxilconv.dll.
char &llvm::LoopSimplifyID = LoopSimplify::ID; |
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/Local.cpp | //===-- Local.cpp - Functions to perform local transformations ------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This family of functions perform various local transformations to the
// program.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/Hashing.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/LibCallSemantics.h"
#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DIBuilder.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/Operator.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/raw_ostream.h"
#include "dxc/DXIL/DxilInstructions.h" // HLSL Change - DxilInst_OutputComplete usage
#include "dxc/DXIL/DxilMetadataHelper.h" // HLSL Change - combine dxil metadata.
#include "dxc/DXIL/DxilOperations.h" // HLSL Change - Get HLSL Opcodes
#include "dxc/DXIL/DxilUtil.h" // HLSL Change - special handling of convergent marker
using namespace llvm;
#define DEBUG_TYPE "local"
STATISTIC(NumRemoved, "Number of unreachable basic blocks removed");
//===----------------------------------------------------------------------===//
// Local constant propagation.
//
/// ConstantFoldTerminator - If a terminator instruction is predicated on a
/// constant value, convert it into an unconditional branch to the constant
/// destination. This is a nontrivial operation because the successors of this
/// basic block must have their PHI nodes updated.
/// Also calls RecursivelyDeleteTriviallyDeadInstructions() on any branch/switch
/// conditions and indirectbr addresses this might make dead if
/// DeleteDeadConditions is true.
bool llvm::ConstantFoldTerminator(BasicBlock *BB, bool DeleteDeadConditions,
const TargetLibraryInfo *TLI) {
TerminatorInst *T = BB->getTerminator();
IRBuilder<> Builder(T);
// Branch - See if we are conditional jumping on constant
if (BranchInst *BI = dyn_cast<BranchInst>(T)) {
if (BI->isUnconditional()) return false; // Can't optimize uncond branch
BasicBlock *Dest1 = BI->getSuccessor(0);
BasicBlock *Dest2 = BI->getSuccessor(1);
if (ConstantInt *Cond = dyn_cast<ConstantInt>(BI->getCondition())) {
// Are we branching on constant?
// YES. Change to unconditional branch...
BasicBlock *Destination = Cond->getZExtValue() ? Dest1 : Dest2;
BasicBlock *OldDest = Cond->getZExtValue() ? Dest2 : Dest1;
//cerr << "Function: " << T->getParent()->getParent()
// << "\nRemoving branch from " << T->getParent()
// << "\n\nTo: " << OldDest << endl;
// Let the basic block know that we are letting go of it. Based on this,
// it will adjust it's PHI nodes.
OldDest->removePredecessor(BB);
// Replace the conditional branch with an unconditional one.
Builder.CreateBr(Destination);
BI->eraseFromParent();
return true;
}
if (Dest2 == Dest1) { // Conditional branch to same location?
// This branch matches something like this:
// br bool %cond, label %Dest, label %Dest
// and changes it into: br label %Dest
// Let the basic block know that we are letting go of one copy of it.
assert(BI->getParent() && "Terminator not inserted in block!");
Dest1->removePredecessor(BI->getParent());
// Replace the conditional branch with an unconditional one.
Builder.CreateBr(Dest1);
Value *Cond = BI->getCondition();
BI->eraseFromParent();
if (DeleteDeadConditions)
RecursivelyDeleteTriviallyDeadInstructions(Cond, TLI);
return true;
}
return false;
}
if (SwitchInst *SI = dyn_cast<SwitchInst>(T)) {
// If we are switching on a constant, we can convert the switch to an
// unconditional branch.
ConstantInt *CI = dyn_cast<ConstantInt>(SI->getCondition());
BasicBlock *DefaultDest = SI->getDefaultDest();
BasicBlock *TheOnlyDest = DefaultDest;
// If the default is unreachable, ignore it when searching for TheOnlyDest.
if (isa<UnreachableInst>(DefaultDest->getFirstNonPHIOrDbg()) &&
SI->getNumCases() > 0) {
TheOnlyDest = SI->case_begin().getCaseSuccessor();
}
// Figure out which case it goes to.
for (SwitchInst::CaseIt i = SI->case_begin(), e = SI->case_end();
i != e; ++i) {
// Found case matching a constant operand?
if (i.getCaseValue() == CI) {
TheOnlyDest = i.getCaseSuccessor();
break;
}
// Check to see if this branch is going to the same place as the default
// dest. If so, eliminate it as an explicit compare.
if (i.getCaseSuccessor() == DefaultDest) {
MDNode *MD = SI->getMetadata(LLVMContext::MD_prof);
unsigned NCases = SI->getNumCases();
// Fold the case metadata into the default if there will be any branches
// left, unless the metadata doesn't match the switch.
if (NCases > 1 && MD && MD->getNumOperands() == 2 + NCases) {
// Collect branch weights into a vector.
SmallVector<uint32_t, 8> Weights;
for (unsigned MD_i = 1, MD_e = MD->getNumOperands(); MD_i < MD_e;
++MD_i) {
ConstantInt *CI =
mdconst::dyn_extract<ConstantInt>(MD->getOperand(MD_i));
assert(CI);
Weights.push_back(CI->getValue().getZExtValue());
}
// Merge weight of this case to the default weight.
unsigned idx = i.getCaseIndex();
Weights[0] += Weights[idx+1];
// Remove weight for this case.
std::swap(Weights[idx+1], Weights.back());
Weights.pop_back();
SI->setMetadata(LLVMContext::MD_prof,
MDBuilder(BB->getContext()).
createBranchWeights(Weights));
}
// Remove this entry.
DefaultDest->removePredecessor(SI->getParent());
SI->removeCase(i);
--i; --e;
continue;
}
// Otherwise, check to see if the switch only branches to one destination.
// We do this by reseting "TheOnlyDest" to null when we find two non-equal
// destinations.
if (i.getCaseSuccessor() != TheOnlyDest) TheOnlyDest = nullptr;
}
if (CI && !TheOnlyDest) {
// Branching on a constant, but not any of the cases, go to the default
// successor.
TheOnlyDest = SI->getDefaultDest();
}
// If we found a single destination that we can fold the switch into, do so
// now.
if (TheOnlyDest) {
// Insert the new branch.
Builder.CreateBr(TheOnlyDest);
BasicBlock *BB = SI->getParent();
// Remove entries from PHI nodes which we no longer branch to...
for (unsigned i = 0, e = SI->getNumSuccessors(); i != e; ++i) {
// Found case matching a constant operand?
BasicBlock *Succ = SI->getSuccessor(i);
if (Succ == TheOnlyDest)
TheOnlyDest = nullptr; // Don't modify the first branch to TheOnlyDest
else
Succ->removePredecessor(BB);
}
// Delete the old switch.
Value *Cond = SI->getCondition();
SI->eraseFromParent();
if (DeleteDeadConditions)
RecursivelyDeleteTriviallyDeadInstructions(Cond, TLI);
return true;
}
if (SI->getNumCases() == 1) {
// Otherwise, we can fold this switch into a conditional branch
// instruction if it has only one non-default destination.
SwitchInst::CaseIt FirstCase = SI->case_begin();
Value *Cond = Builder.CreateICmpEQ(SI->getCondition(),
FirstCase.getCaseValue(), "cond");
// Insert the new branch.
BranchInst *NewBr = Builder.CreateCondBr(Cond,
FirstCase.getCaseSuccessor(),
SI->getDefaultDest());
MDNode *MD = SI->getMetadata(LLVMContext::MD_prof);
if (MD && MD->getNumOperands() == 3) {
ConstantInt *SICase =
mdconst::dyn_extract<ConstantInt>(MD->getOperand(2));
ConstantInt *SIDef =
mdconst::dyn_extract<ConstantInt>(MD->getOperand(1));
assert(SICase && SIDef);
// The TrueWeight should be the weight for the single case of SI.
NewBr->setMetadata(LLVMContext::MD_prof,
MDBuilder(BB->getContext()).
createBranchWeights(SICase->getValue().getZExtValue(),
SIDef->getValue().getZExtValue()));
}
// Delete the old switch.
SI->eraseFromParent();
return true;
}
return false;
}
if (IndirectBrInst *IBI = dyn_cast<IndirectBrInst>(T)) {
// indirectbr blockaddress(@F, @BB) -> br label @BB
if (BlockAddress *BA =
dyn_cast<BlockAddress>(IBI->getAddress()->stripPointerCasts())) {
BasicBlock *TheOnlyDest = BA->getBasicBlock();
// Insert the new branch.
Builder.CreateBr(TheOnlyDest);
for (unsigned i = 0, e = IBI->getNumDestinations(); i != e; ++i) {
if (IBI->getDestination(i) == TheOnlyDest)
TheOnlyDest = nullptr;
else
IBI->getDestination(i)->removePredecessor(IBI->getParent());
}
Value *Address = IBI->getAddress();
IBI->eraseFromParent();
if (DeleteDeadConditions)
RecursivelyDeleteTriviallyDeadInstructions(Address, TLI);
// If we didn't find our destination in the IBI successor list, then we
// have undefined behavior. Replace the unconditional branch with an
// 'unreachable' instruction.
if (TheOnlyDest) {
BB->getTerminator()->eraseFromParent();
new UnreachableInst(BB->getContext(), BB);
}
return true;
}
}
return false;
}
//===----------------------------------------------------------------------===//
// Local dead code elimination.
//
/// isInstructionTriviallyDead - Return true if the result produced by the
/// instruction is not used, and the instruction has no side effects.
///
bool llvm::isInstructionTriviallyDead(Instruction *I,
const TargetLibraryInfo *TLI) {
if (!I->use_empty() || isa<TerminatorInst>(I)) return false;
// We don't want the landingpad instruction removed by anything this general.
if (isa<LandingPadInst>(I))
return false;
// We don't want debug info removed by anything this general, unless
// debug info is empty.
if (DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(I)) {
if (DDI->getAddress())
return false;
return true;
}
if (DbgValueInst *DVI = dyn_cast<DbgValueInst>(I)) {
if (DVI->getValue())
return false;
return true;
}
if (!I->mayHaveSideEffects()) return true;
// Special case intrinsics that "may have side effects" but can be deleted
// when dead.
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I)) {
// Safe to delete llvm.stacksave if dead.
if (II->getIntrinsicID() == Intrinsic::stacksave)
return true;
// Lifetime intrinsics are dead when their right-hand is undef.
if (II->getIntrinsicID() == Intrinsic::lifetime_start ||
II->getIntrinsicID() == Intrinsic::lifetime_end)
return isa<UndefValue>(II->getArgOperand(1));
// Assumptions are dead if their condition is trivially true.
if (II->getIntrinsicID() == Intrinsic::assume) {
if (ConstantInt *Cond = dyn_cast<ConstantInt>(II->getArgOperand(0)))
return !Cond->isZero();
return false;
}
}
if (isAllocLikeFn(I, TLI)) return true;
if (CallInst *CI = isFreeCall(I, TLI))
if (Constant *C = dyn_cast<Constant>(CI->getArgOperand(0)))
return C->isNullValue() || isa<UndefValue>(C);
// HLSL Change - Verify that function has no side effects
if (hlsl::dxilutil::FunctionHasNoSideEffects(I))
return true;
// HLSL Change End
return false;
}
/// RecursivelyDeleteTriviallyDeadInstructions - If the specified value is a
/// trivially dead instruction, delete it. If that makes any of its operands
/// trivially dead, delete them too, recursively. Return true if any
/// instructions were deleted.
bool
llvm::RecursivelyDeleteTriviallyDeadInstructions(Value *V,
const TargetLibraryInfo *TLI) {
Instruction *I = dyn_cast<Instruction>(V);
if (!I || !I->use_empty() || !isInstructionTriviallyDead(I, TLI))
return false;
SmallVector<Instruction*, 16> DeadInsts;
DeadInsts.push_back(I);
do {
I = DeadInsts.pop_back_val();
// Null out all of the instruction's operands to see if any operand becomes
// dead as we go.
for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i) {
Value *OpV = I->getOperand(i);
I->setOperand(i, nullptr);
if (!OpV->use_empty()) continue;
// If the operand is an instruction that became dead as we nulled out the
// operand, and if it is 'trivially' dead, delete it in a future loop
// iteration.
if (Instruction *OpI = dyn_cast<Instruction>(OpV))
if (isInstructionTriviallyDead(OpI, TLI))
DeadInsts.push_back(OpI);
}
I->eraseFromParent();
} while (!DeadInsts.empty());
return true;
}
/// areAllUsesEqual - Check whether the uses of a value are all the same.
/// This is similar to Instruction::hasOneUse() except this will also return
/// true when there are no uses or multiple uses that all refer to the same
/// value.
static bool areAllUsesEqual(Instruction *I) {
Value::user_iterator UI = I->user_begin();
Value::user_iterator UE = I->user_end();
if (UI == UE)
return true;
User *TheUse = *UI;
for (++UI; UI != UE; ++UI) {
if (*UI != TheUse)
return false;
}
return true;
}
/// RecursivelyDeleteDeadPHINode - If the specified value is an effectively
/// dead PHI node, due to being a def-use chain of single-use nodes that
/// either forms a cycle or is terminated by a trivially dead instruction,
/// delete it. If that makes any of its operands trivially dead, delete them
/// too, recursively. Return true if a change was made.
bool llvm::RecursivelyDeleteDeadPHINode(PHINode *PN,
const TargetLibraryInfo *TLI) {
SmallPtrSet<Instruction*, 4> Visited;
for (Instruction *I = PN; areAllUsesEqual(I) && !I->mayHaveSideEffects();
I = cast<Instruction>(*I->user_begin())) {
if (I->use_empty())
return RecursivelyDeleteTriviallyDeadInstructions(I, TLI);
// If we find an instruction more than once, we're on a cycle that
// won't prove fruitful.
if (!Visited.insert(I).second) {
// Break the cycle and delete the instruction and its operands.
I->replaceAllUsesWith(UndefValue::get(I->getType()));
(void)RecursivelyDeleteTriviallyDeadInstructions(I, TLI);
return true;
}
}
return false;
}
/// SimplifyInstructionsInBlock - Scan the specified basic block and try to
/// simplify any instructions in it and recursively delete dead instructions.
///
/// This returns true if it changed the code, note that it can delete
/// instructions in other blocks as well in this block.
bool llvm::SimplifyInstructionsInBlock(BasicBlock *BB,
const TargetLibraryInfo *TLI) {
bool MadeChange = false;
#ifndef NDEBUG
// In debug builds, ensure that the terminator of the block is never replaced
// or deleted by these simplifications. The idea of simplification is that it
// cannot introduce new instructions, and there is no way to replace the
// terminator of a block without introducing a new instruction.
AssertingVH<Instruction> TerminatorVH(--BB->end());
#endif
for (BasicBlock::iterator BI = BB->begin(), E = --BB->end(); BI != E; ) {
assert(!BI->isTerminator());
Instruction *Inst = BI++;
WeakTrackingVH BIHandle(BI);
if (recursivelySimplifyInstruction(Inst, TLI)) {
MadeChange = true;
if (BIHandle != BI)
BI = BB->begin();
continue;
}
MadeChange |= RecursivelyDeleteTriviallyDeadInstructions(Inst, TLI);
if (BIHandle != BI)
BI = BB->begin();
}
return MadeChange;
}
//===----------------------------------------------------------------------===//
// Control Flow Graph Restructuring.
//
/// RemovePredecessorAndSimplify - Like BasicBlock::removePredecessor, this
/// method is called when we're about to delete Pred as a predecessor of BB. If
/// BB contains any PHI nodes, this drops the entries in the PHI nodes for Pred.
///
/// Unlike the removePredecessor method, this attempts to simplify uses of PHI
/// nodes that collapse into identity values. For example, if we have:
/// x = phi(1, 0, 0, 0)
/// y = and x, z
///
/// .. and delete the predecessor corresponding to the '1', this will attempt to
/// recursively fold the and to 0.
void llvm::RemovePredecessorAndSimplify(BasicBlock *BB, BasicBlock *Pred) {
// This only adjusts blocks with PHI nodes.
if (!isa<PHINode>(BB->begin()))
return;
// Remove the entries for Pred from the PHI nodes in BB, but do not simplify
// them down. This will leave us with single entry phi nodes and other phis
// that can be removed.
BB->removePredecessor(Pred, true);
WeakTrackingVH PhiIt = &BB->front();
while (PHINode *PN = dyn_cast<PHINode>(PhiIt)) {
PhiIt = &*++BasicBlock::iterator(cast<Instruction>(PhiIt));
Value *OldPhiIt = PhiIt;
if (!recursivelySimplifyInstruction(PN))
continue;
// If recursive simplification ended up deleting the next PHI node we would
// iterate to, then our iterator is invalid, restart scanning from the top
// of the block.
if (PhiIt != OldPhiIt) PhiIt = &BB->front();
}
}
/// MergeBasicBlockIntoOnlyPred - DestBB is a block with one predecessor and its
/// predecessor is known to have one successor (DestBB!). Eliminate the edge
/// between them, moving the instructions in the predecessor into DestBB and
/// deleting the predecessor block.
///
void llvm::MergeBasicBlockIntoOnlyPred(BasicBlock *DestBB, DominatorTree *DT) {
// If BB has single-entry PHI nodes, fold them.
while (PHINode *PN = dyn_cast<PHINode>(DestBB->begin())) {
Value *NewVal = PN->getIncomingValue(0);
// Replace self referencing PHI with undef, it must be dead.
if (NewVal == PN) NewVal = UndefValue::get(PN->getType());
PN->replaceAllUsesWith(NewVal);
PN->eraseFromParent();
}
BasicBlock *PredBB = DestBB->getSinglePredecessor();
assert(PredBB && "Block doesn't have a single predecessor!");
// Zap anything that took the address of DestBB. Not doing this will give the
// address an invalid value.
if (DestBB->hasAddressTaken()) {
BlockAddress *BA = BlockAddress::get(DestBB);
Constant *Replacement =
ConstantInt::get(llvm::Type::getInt32Ty(BA->getContext()), 1);
BA->replaceAllUsesWith(ConstantExpr::getIntToPtr(Replacement,
BA->getType()));
BA->destroyConstant();
}
// Anything that branched to PredBB now branches to DestBB.
PredBB->replaceAllUsesWith(DestBB);
// Splice all the instructions from PredBB to DestBB.
PredBB->getTerminator()->eraseFromParent();
DestBB->getInstList().splice(DestBB->begin(), PredBB->getInstList());
// If the PredBB is the entry block of the function, move DestBB up to
// become the entry block after we erase PredBB.
if (PredBB == &DestBB->getParent()->getEntryBlock())
DestBB->moveAfter(PredBB);
if (DT) {
BasicBlock *PredBBIDom = DT->getNode(PredBB)->getIDom()->getBlock();
DT->changeImmediateDominator(DestBB, PredBBIDom);
DT->eraseNode(PredBB);
}
// Nuke BB.
PredBB->eraseFromParent();
}
/// CanMergeValues - Return true if we can choose one of these values to use
/// in place of the other. Note that we will always choose the non-undef
/// value to keep.
static bool CanMergeValues(Value *First, Value *Second) {
return First == Second;
// HLSL Change Begin -Not merge undef.
// || isa<UndefValue>(First) || isa<UndefValue>(Second);
// HLSL Change End.
}
/// CanPropagatePredecessorsForPHIs - Return true if we can fold BB, an
/// almost-empty BB ending in an unconditional branch to Succ, into Succ.
///
/// Assumption: Succ is the single successor for BB.
///
static bool CanPropagatePredecessorsForPHIs(BasicBlock *BB, BasicBlock *Succ) {
assert(*succ_begin(BB) == Succ && "Succ is not successor of BB!");
DEBUG(dbgs() << "Looking to fold " << BB->getName() << " into "
<< Succ->getName() << "\n");
// Shortcut, if there is only a single predecessor it must be BB and merging
// is always safe
if (Succ->getSinglePredecessor()) return true;
// Make a list of the predecessors of BB
SmallPtrSet<BasicBlock*, 16> BBPreds(pred_begin(BB), pred_end(BB));
// Look at all the phi nodes in Succ, to see if they present a conflict when
// merging these blocks
for (BasicBlock::iterator I = Succ->begin(); isa<PHINode>(I); ++I) {
PHINode *PN = cast<PHINode>(I);
// If the incoming value from BB is again a PHINode in
// BB which has the same incoming value for *PI as PN does, we can
// merge the phi nodes and then the blocks can still be merged
PHINode *BBPN = dyn_cast<PHINode>(PN->getIncomingValueForBlock(BB));
if (BBPN && BBPN->getParent() == BB) {
for (unsigned PI = 0, PE = PN->getNumIncomingValues(); PI != PE; ++PI) {
BasicBlock *IBB = PN->getIncomingBlock(PI);
if (BBPreds.count(IBB) &&
!CanMergeValues(BBPN->getIncomingValueForBlock(IBB),
PN->getIncomingValue(PI))) {
DEBUG(dbgs() << "Can't fold, phi node " << PN->getName() << " in "
<< Succ->getName() << " is conflicting with "
<< BBPN->getName() << " with regard to common predecessor "
<< IBB->getName() << "\n");
return false;
}
}
} else {
Value* Val = PN->getIncomingValueForBlock(BB);
for (unsigned PI = 0, PE = PN->getNumIncomingValues(); PI != PE; ++PI) {
// See if the incoming value for the common predecessor is equal to the
// one for BB, in which case this phi node will not prevent the merging
// of the block.
BasicBlock *IBB = PN->getIncomingBlock(PI);
if (BBPreds.count(IBB) &&
!CanMergeValues(Val, PN->getIncomingValue(PI))) {
DEBUG(dbgs() << "Can't fold, phi node " << PN->getName() << " in "
<< Succ->getName() << " is conflicting with regard to common "
<< "predecessor " << IBB->getName() << "\n");
return false;
}
}
}
}
return true;
}
typedef SmallVector<BasicBlock *, 16> PredBlockVector;
typedef DenseMap<BasicBlock *, Value *> IncomingValueMap;
/// \brief Determines the value to use as the phi node input for a block.
///
/// Select between \p OldVal any value that we know flows from \p BB
/// to a particular phi on the basis of which one (if either) is not
/// undef. Update IncomingValues based on the selected value.
///
/// \param OldVal The value we are considering selecting.
/// \param BB The block that the value flows in from.
/// \param IncomingValues A map from block-to-value for other phi inputs
/// that we have examined.
///
/// \returns the selected value.
static Value *selectIncomingValueForBlock(Value *OldVal, BasicBlock *BB,
IncomingValueMap &IncomingValues) {
if (!isa<UndefValue>(OldVal)) {
assert((!IncomingValues.count(BB) ||
IncomingValues.find(BB)->second == OldVal) &&
"Expected OldVal to match incoming value from BB!");
IncomingValues.insert(std::make_pair(BB, OldVal));
return OldVal;
}
IncomingValueMap::const_iterator It = IncomingValues.find(BB);
if (It != IncomingValues.end()) return It->second;
return OldVal;
}
/// \brief Create a map from block to value for the operands of a
/// given phi.
///
/// Create a map from block to value for each non-undef value flowing
/// into \p PN.
///
/// \param PN The phi we are collecting the map for.
/// \param IncomingValues [out] The map from block to value for this phi.
static void gatherIncomingValuesToPhi(PHINode *PN,
IncomingValueMap &IncomingValues) {
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
BasicBlock *BB = PN->getIncomingBlock(i);
Value *V = PN->getIncomingValue(i);
if (!isa<UndefValue>(V))
IncomingValues.insert(std::make_pair(BB, V));
}
}
/// \brief Replace the incoming undef values to a phi with the values
/// from a block-to-value map.
///
/// \param PN The phi we are replacing the undefs in.
/// \param IncomingValues A map from block to value.
static void replaceUndefValuesInPhi(PHINode *PN,
const IncomingValueMap &IncomingValues) {
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
Value *V = PN->getIncomingValue(i);
if (!isa<UndefValue>(V)) continue;
BasicBlock *BB = PN->getIncomingBlock(i);
IncomingValueMap::const_iterator It = IncomingValues.find(BB);
if (It == IncomingValues.end()) continue;
PN->setIncomingValue(i, It->second);
}
}
/// \brief Replace a value flowing from a block to a phi with
/// potentially multiple instances of that value flowing from the
/// block's predecessors to the phi.
///
/// \param BB The block with the value flowing into the phi.
/// \param BBPreds The predecessors of BB.
/// \param PN The phi that we are updating.
static void redirectValuesFromPredecessorsToPhi(BasicBlock *BB,
const PredBlockVector &BBPreds,
PHINode *PN) {
Value *OldVal = PN->removeIncomingValue(BB, false);
assert(OldVal && "No entry in PHI for Pred BB!");
IncomingValueMap IncomingValues;
// We are merging two blocks - BB, and the block containing PN - and
// as a result we need to redirect edges from the predecessors of BB
// to go to the block containing PN, and update PN
// accordingly. Since we allow merging blocks in the case where the
// predecessor and successor blocks both share some predecessors,
// and where some of those common predecessors might have undef
// values flowing into PN, we want to rewrite those values to be
// consistent with the non-undef values.
gatherIncomingValuesToPhi(PN, IncomingValues);
// If this incoming value is one of the PHI nodes in BB, the new entries
// in the PHI node are the entries from the old PHI.
if (isa<PHINode>(OldVal) && cast<PHINode>(OldVal)->getParent() == BB) {
PHINode *OldValPN = cast<PHINode>(OldVal);
for (unsigned i = 0, e = OldValPN->getNumIncomingValues(); i != e; ++i) {
// Note that, since we are merging phi nodes and BB and Succ might
// have common predecessors, we could end up with a phi node with
// identical incoming branches. This will be cleaned up later (and
// will trigger asserts if we try to clean it up now, without also
// simplifying the corresponding conditional branch).
BasicBlock *PredBB = OldValPN->getIncomingBlock(i);
Value *PredVal = OldValPN->getIncomingValue(i);
Value *Selected = selectIncomingValueForBlock(PredVal, PredBB,
IncomingValues);
// And add a new incoming value for this predecessor for the
// newly retargeted branch.
PN->addIncoming(Selected, PredBB);
}
} else {
for (unsigned i = 0, e = BBPreds.size(); i != e; ++i) {
// Update existing incoming values in PN for this
// predecessor of BB.
BasicBlock *PredBB = BBPreds[i];
Value *Selected = selectIncomingValueForBlock(OldVal, PredBB,
IncomingValues);
// And add a new incoming value for this predecessor for the
// newly retargeted branch.
PN->addIncoming(Selected, PredBB);
}
}
replaceUndefValuesInPhi(PN, IncomingValues);
}
/// TryToSimplifyUncondBranchFromEmptyBlock - BB is known to contain an
/// unconditional branch, and contains no instructions other than PHI nodes,
/// potential side-effect free intrinsics and the branch. If possible,
/// eliminate BB by rewriting all the predecessors to branch to the successor
/// block and return true. If we can't transform, return false.
bool llvm::TryToSimplifyUncondBranchFromEmptyBlock(BasicBlock *BB) {
assert(BB != &BB->getParent()->getEntryBlock() &&
"TryToSimplifyUncondBranchFromEmptyBlock called on entry block!");
// We can't eliminate infinite loops.
BasicBlock *Succ = cast<BranchInst>(BB->getTerminator())->getSuccessor(0);
if (BB == Succ) return false;
// Check to see if merging these blocks would cause conflicts for any of the
// phi nodes in BB or Succ. If not, we can safely merge.
if (!CanPropagatePredecessorsForPHIs(BB, Succ)) return false;
// Check for cases where Succ has multiple predecessors and a PHI node in BB
// has uses which will not disappear when the PHI nodes are merged. It is
// possible to handle such cases, but difficult: it requires checking whether
// BB dominates Succ, which is non-trivial to calculate in the case where
// Succ has multiple predecessors. Also, it requires checking whether
// constructing the necessary self-referential PHI node doesn't introduce any
// conflicts; this isn't too difficult, but the previous code for doing this
// was incorrect.
//
// Note that if this check finds a live use, BB dominates Succ, so BB is
// something like a loop pre-header (or rarely, a part of an irreducible CFG);
// folding the branch isn't profitable in that case anyway.
if (!Succ->getSinglePredecessor()) {
BasicBlock::iterator BBI = BB->begin();
while (isa<PHINode>(*BBI)) {
for (Use &U : BBI->uses()) {
if (PHINode* PN = dyn_cast<PHINode>(U.getUser())) {
if (PN->getIncomingBlock(U) != BB)
return false;
} else {
return false;
}
}
++BBI;
}
}
DEBUG(dbgs() << "Killing Trivial BB: \n" << *BB);
if (isa<PHINode>(Succ->begin())) {
// If there is more than one pred of succ, and there are PHI nodes in
// the successor, then we need to add incoming edges for the PHI nodes
//
const PredBlockVector BBPreds(pred_begin(BB), pred_end(BB));
// Loop over all of the PHI nodes in the successor of BB.
for (BasicBlock::iterator I = Succ->begin(); isa<PHINode>(I); ++I) {
PHINode *PN = cast<PHINode>(I);
redirectValuesFromPredecessorsToPhi(BB, BBPreds, PN);
}
}
if (Succ->getSinglePredecessor()) {
// BB is the only predecessor of Succ, so Succ will end up with exactly
// the same predecessors BB had.
// Copy over any phi, debug or lifetime instruction.
BB->getTerminator()->eraseFromParent();
Succ->getInstList().splice(Succ->getFirstNonPHI(), BB->getInstList());
} else {
while (PHINode *PN = dyn_cast<PHINode>(&BB->front())) {
// We explicitly check for such uses in CanPropagatePredecessorsForPHIs.
assert(PN->use_empty() && "There shouldn't be any uses here!");
PN->eraseFromParent();
}
}
// Everything that jumped to BB now goes to Succ.
BB->replaceAllUsesWith(Succ);
if (!Succ->hasName()) Succ->takeName(BB);
BB->eraseFromParent(); // Delete the old basic block.
return true;
}
/// EliminateDuplicatePHINodes - Check for and eliminate duplicate PHI
/// nodes in this block. This doesn't try to be clever about PHI nodes
/// which differ only in the order of the incoming values, but instcombine
/// orders them so it usually won't matter.
///
bool llvm::EliminateDuplicatePHINodes(BasicBlock *BB) {
// This implementation doesn't currently consider undef operands
// specially. Theoretically, two phis which are identical except for
// one having an undef where the other doesn't could be collapsed.
struct PHIDenseMapInfo {
static PHINode *getEmptyKey() {
return DenseMapInfo<PHINode *>::getEmptyKey();
}
static PHINode *getTombstoneKey() {
return DenseMapInfo<PHINode *>::getTombstoneKey();
}
static unsigned getHashValue(PHINode *PN) {
// Compute a hash value on the operands. Instcombine will likely have
// sorted them, which helps expose duplicates, but we have to check all
// the operands to be safe in case instcombine hasn't run.
return static_cast<unsigned>(hash_combine(
hash_combine_range(PN->value_op_begin(), PN->value_op_end()),
hash_combine_range(PN->block_begin(), PN->block_end())));
}
static bool isEqual(PHINode *LHS, PHINode *RHS) {
if (LHS == getEmptyKey() || LHS == getTombstoneKey() ||
RHS == getEmptyKey() || RHS == getTombstoneKey())
return LHS == RHS;
return LHS->isIdenticalTo(RHS);
}
};
// Set of unique PHINodes.
DenseSet<PHINode *, PHIDenseMapInfo> PHISet;
// Examine each PHI.
bool Changed = false;
for (auto I = BB->begin(); PHINode *PN = dyn_cast<PHINode>(I++);) {
auto Inserted = PHISet.insert(PN);
if (!Inserted.second) {
// A duplicate. Replace this PHI with its duplicate.
PN->replaceAllUsesWith(*Inserted.first);
PN->eraseFromParent();
Changed = true;
}
}
return Changed;
}
/// enforceKnownAlignment - If the specified pointer points to an object that
/// we control, modify the object's alignment to PrefAlign. This isn't
/// often possible though. If alignment is important, a more reliable approach
/// is to simply align all global variables and allocation instructions to
/// their preferred alignment from the beginning.
///
static unsigned enforceKnownAlignment(Value *V, unsigned Align,
unsigned PrefAlign,
const DataLayout &DL) {
V = V->stripPointerCasts();
if (AllocaInst *AI = dyn_cast<AllocaInst>(V)) {
// If the preferred alignment is greater than the natural stack alignment
// then don't round up. This avoids dynamic stack realignment.
if (DL.exceedsNaturalStackAlignment(PrefAlign))
return Align;
// If there is a requested alignment and if this is an alloca, round up.
if (AI->getAlignment() >= PrefAlign)
return AI->getAlignment();
AI->setAlignment(PrefAlign);
return PrefAlign;
}
if (auto *GO = dyn_cast<GlobalObject>(V)) {
// If there is a large requested alignment and we can, bump up the alignment
// of the global. If the memory we set aside for the global may not be the
// memory used by the final program then it is impossible for us to reliably
// enforce the preferred alignment.
if (!GO->isStrongDefinitionForLinker())
return Align;
if (GO->getAlignment() >= PrefAlign)
return GO->getAlignment();
// We can only increase the alignment of the global if it has no alignment
// specified or if it is not assigned a section. If it is assigned a
// section, the global could be densely packed with other objects in the
// section, increasing the alignment could cause padding issues.
if (!GO->hasSection() || GO->getAlignment() == 0)
GO->setAlignment(PrefAlign);
return GO->getAlignment();
}
return Align;
}
/// getOrEnforceKnownAlignment - If the specified pointer has an alignment that
/// we can determine, return it, otherwise return 0. If PrefAlign is specified,
/// and it is more than the alignment of the ultimate object, see if we can
/// increase the alignment of the ultimate object, making this check succeed.
unsigned llvm::getOrEnforceKnownAlignment(Value *V, unsigned PrefAlign,
const DataLayout &DL,
const Instruction *CxtI,
AssumptionCache *AC,
const DominatorTree *DT) {
assert(V->getType()->isPointerTy() &&
"getOrEnforceKnownAlignment expects a pointer!");
unsigned BitWidth = DL.getPointerTypeSizeInBits(V->getType());
APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
computeKnownBits(V, KnownZero, KnownOne, DL, 0, AC, CxtI, DT);
unsigned TrailZ = KnownZero.countTrailingOnes();
// Avoid trouble with ridiculously large TrailZ values, such as
// those computed from a null pointer.
TrailZ = std::min(TrailZ, unsigned(sizeof(unsigned) * CHAR_BIT - 1));
unsigned Align = 1u << std::min(BitWidth - 1, TrailZ);
// LLVM doesn't support alignments larger than this currently.
Align = std::min(Align, +Value::MaximumAlignment);
if (PrefAlign > Align)
Align = enforceKnownAlignment(V, Align, PrefAlign, DL);
// We don't need to make any adjustment.
return Align;
}
///===---------------------------------------------------------------------===//
/// Dbg Intrinsic utilities
///
/// See if there is a dbg.value intrinsic for DIVar before I.
static bool LdStHasDebugValue(const DILocalVariable *DIVar, Instruction *I) {
// Since we can't guarantee that the original dbg.declare instrinsic
// is removed by LowerDbgDeclare(), we need to make sure that we are
// not inserting the same dbg.value intrinsic over and over.
llvm::BasicBlock::InstListType::iterator PrevI(I);
if (PrevI != I->getParent()->getInstList().begin()) {
--PrevI;
if (DbgValueInst *DVI = dyn_cast<DbgValueInst>(PrevI))
if (DVI->getValue() == I->getOperand(0) &&
DVI->getOffset() == 0 &&
DVI->getVariable() == DIVar)
return true;
}
return false;
}
/// Inserts a llvm.dbg.value intrinsic before a store to an alloca'd value
/// that has an associated llvm.dbg.decl intrinsic.
bool llvm::ConvertDebugDeclareToDebugValue(DbgDeclareInst *DDI,
StoreInst *SI, DIBuilder &Builder) {
auto *DIVar = DDI->getVariable();
auto *DIExpr = DDI->getExpression();
assert(DIVar && "Missing variable");
if (LdStHasDebugValue(DIVar, SI))
return true;
// If an argument is zero extended then use argument directly. The ZExt
// may be zapped by an optimization pass in future.
Argument *ExtendedArg = nullptr;
if (ZExtInst *ZExt = dyn_cast<ZExtInst>(SI->getOperand(0)))
ExtendedArg = dyn_cast<Argument>(ZExt->getOperand(0));
if (SExtInst *SExt = dyn_cast<SExtInst>(SI->getOperand(0)))
ExtendedArg = dyn_cast<Argument>(SExt->getOperand(0));
if (ExtendedArg)
Builder.insertDbgValueIntrinsic(ExtendedArg, 0, DIVar, DIExpr,
DDI->getDebugLoc(), SI);
else
Builder.insertDbgValueIntrinsic(SI->getOperand(0), 0, DIVar, DIExpr,
DDI->getDebugLoc(), SI);
return true;
}
/// Inserts a llvm.dbg.value intrinsic before a load of an alloca'd value
/// that has an associated llvm.dbg.decl intrinsic.
bool llvm::ConvertDebugDeclareToDebugValue(DbgDeclareInst *DDI,
LoadInst *LI, DIBuilder &Builder) {
auto *DIVar = DDI->getVariable();
auto *DIExpr = DDI->getExpression();
assert(DIVar && "Missing variable");
if (LdStHasDebugValue(DIVar, LI))
return true;
Builder.insertDbgValueIntrinsic(LI->getOperand(0), 0, DIVar, DIExpr,
DDI->getDebugLoc(), LI);
return true;
}
/// Determine whether this alloca is either a VLA or an array.
static bool isArray(AllocaInst *AI) {
return AI->isArrayAllocation() ||
AI->getType()->getElementType()->isArrayTy();
}
/// LowerDbgDeclare - Lowers llvm.dbg.declare intrinsics into appropriate set
/// of llvm.dbg.value intrinsics.
bool llvm::LowerDbgDeclare(Function &F) {
DIBuilder DIB(*F.getParent(), /*AllowUnresolved*/ false);
SmallVector<DbgDeclareInst *, 4> Dbgs;
for (auto &FI : F)
for (BasicBlock::iterator BI : FI)
if (auto DDI = dyn_cast<DbgDeclareInst>(BI))
Dbgs.push_back(DDI);
if (Dbgs.empty())
return false;
for (auto &I : Dbgs) {
DbgDeclareInst *DDI = I;
AllocaInst *AI = dyn_cast_or_null<AllocaInst>(DDI->getAddress());
// If this is an alloca for a scalar variable, insert a dbg.value
// at each load and store to the alloca and erase the dbg.declare.
// The dbg.values allow tracking a variable even if it is not
// stored on the stack, while the dbg.declare can only describe
// the stack slot (and at a lexical-scope granularity). Later
// passes will attempt to elide the stack slot.
if (AI && !isArray(AI)) {
for (User *U : AI->users())
if (StoreInst *SI = dyn_cast<StoreInst>(U))
ConvertDebugDeclareToDebugValue(DDI, SI, DIB);
else if (LoadInst *LI = dyn_cast<LoadInst>(U))
ConvertDebugDeclareToDebugValue(DDI, LI, DIB);
else if (CallInst *CI = dyn_cast<CallInst>(U)) {
// This is a call by-value or some other instruction that
// takes a pointer to the variable. Insert a *value*
// intrinsic that describes the alloca.
DIB.insertDbgValueIntrinsic(AI, 0, DDI->getVariable(),
DDI->getExpression(), DDI->getDebugLoc(),
CI);
}
DDI->eraseFromParent();
}
}
return true;
}
/// FindAllocaDbgDeclare - Finds the llvm.dbg.declare intrinsic describing the
/// alloca 'V', if any.
DbgDeclareInst *llvm::FindAllocaDbgDeclare(Value *V) {
if (auto *L = LocalAsMetadata::getIfExists(V))
if (auto *MDV = MetadataAsValue::getIfExists(V->getContext(), L))
for (User *U : MDV->users())
if (DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(U))
return DDI;
return nullptr;
}
// HLSL Change - Begin
/// FindAllocaDbgDeclare - Finds the llvm.dbg.declare intrinsic corresponding to
/// an alloca, if any.
void llvm::FindAllocaDbgDeclare(Value *V, SmallVectorImpl<DbgDeclareInst *> &Declares) {
if (auto *L = LocalAsMetadata::getIfExists(V))
if (auto *MDV = MetadataAsValue::getIfExists(V->getContext(), L))
for (User *U : MDV->users())
if (DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(U))
Declares.push_back(DDI);
}
// HLSL Change - End
bool llvm::replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
DIBuilder &Builder, bool Deref) {
DbgDeclareInst *DDI = FindAllocaDbgDeclare(AI);
if (!DDI)
return false;
DebugLoc Loc = DDI->getDebugLoc();
auto *DIVar = DDI->getVariable();
auto *DIExpr = DDI->getExpression();
assert(DIVar && "Missing variable");
if (Deref) {
// Create a copy of the original DIDescriptor for user variable, prepending
// "deref" operation to a list of address elements, as new llvm.dbg.declare
// will take a value storing address of the memory for variable, not
// alloca itself.
SmallVector<uint64_t, 4> NewDIExpr;
NewDIExpr.push_back(dwarf::DW_OP_deref);
if (DIExpr)
NewDIExpr.append(DIExpr->elements_begin(), DIExpr->elements_end());
DIExpr = Builder.createExpression(NewDIExpr);
}
// Insert llvm.dbg.declare in the same basic block as the original alloca,
// and remove old llvm.dbg.declare.
BasicBlock *BB = AI->getParent();
Builder.insertDeclare(NewAllocaAddress, DIVar, DIExpr, Loc, BB);
DDI->eraseFromParent();
return true;
}
/// changeToUnreachable - Insert an unreachable instruction before the specified
/// instruction, making it and the rest of the code in the block dead.
static void changeToUnreachable(Instruction *I, bool UseLLVMTrap) {
BasicBlock *BB = I->getParent();
// Loop over all of the successors, removing BB's entry from any PHI
// nodes.
for (succ_iterator SI = succ_begin(BB), SE = succ_end(BB); SI != SE; ++SI)
(*SI)->removePredecessor(BB);
// Insert a call to llvm.trap right before this. This turns the undefined
// behavior into a hard fail instead of falling through into random code.
if (UseLLVMTrap) {
Function *TrapFn =
Intrinsic::getDeclaration(BB->getParent()->getParent(), Intrinsic::trap);
CallInst *CallTrap = CallInst::Create(TrapFn, "", I);
CallTrap->setDebugLoc(I->getDebugLoc());
}
new UnreachableInst(I->getContext(), I);
// All instructions after this are dead.
BasicBlock::iterator BBI = I, BBE = BB->end();
while (BBI != BBE) {
if (!BBI->use_empty())
BBI->replaceAllUsesWith(UndefValue::get(BBI->getType()));
BB->getInstList().erase(BBI++);
}
}
/// changeToCall - Convert the specified invoke into a normal call.
static void changeToCall(InvokeInst *II) {
SmallVector<Value*, 8> Args(II->op_begin(), II->op_end() - 3);
CallInst *NewCall = CallInst::Create(II->getCalledValue(), Args, "", II);
NewCall->takeName(II);
NewCall->setCallingConv(II->getCallingConv());
NewCall->setAttributes(II->getAttributes());
NewCall->setDebugLoc(II->getDebugLoc());
II->replaceAllUsesWith(NewCall);
// Follow the call by a branch to the normal destination.
BranchInst::Create(II->getNormalDest(), II);
// Update PHI nodes in the unwind destination
II->getUnwindDest()->removePredecessor(II->getParent());
II->eraseFromParent();
}
static bool markAliveBlocks(Function &F,
SmallPtrSetImpl<BasicBlock*> &Reachable) {
SmallVector<BasicBlock*, 128> Worklist;
BasicBlock *BB = F.begin();
Worklist.push_back(BB);
Reachable.insert(BB);
bool Changed = false;
do {
BB = Worklist.pop_back_val();
// Do a quick scan of the basic block, turning any obviously unreachable
// instructions into LLVM unreachable insts. The instruction combining pass
// canonicalizes unreachable insts into stores to null or undef.
for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E;++BBI){
// Assumptions that are known to be false are equivalent to unreachable.
// Also, if the condition is undefined, then we make the choice most
// beneficial to the optimizer, and choose that to also be unreachable.
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(BBI))
if (II->getIntrinsicID() == Intrinsic::assume) {
bool MakeUnreachable = false;
if (isa<UndefValue>(II->getArgOperand(0)))
MakeUnreachable = true;
else if (ConstantInt *Cond =
dyn_cast<ConstantInt>(II->getArgOperand(0)))
MakeUnreachable = Cond->isZero();
if (MakeUnreachable) {
// Don't insert a call to llvm.trap right before the unreachable.
changeToUnreachable(BBI, false);
Changed = true;
break;
}
}
if (CallInst *CI = dyn_cast<CallInst>(BBI)) {
if (CI->doesNotReturn()) {
// If we found a call to a no-return function, insert an unreachable
// instruction after it. Make sure there isn't *already* one there
// though.
++BBI;
if (!isa<UnreachableInst>(BBI)) {
// Don't insert a call to llvm.trap right before the unreachable.
changeToUnreachable(BBI, false);
Changed = true;
}
break;
}
}
// Store to undef and store to null are undefined and used to signal that
// they should be changed to unreachable by passes that can't modify the
// CFG.
if (StoreInst *SI = dyn_cast<StoreInst>(BBI)) {
// Don't touch volatile stores.
if (SI->isVolatile()) continue;
Value *Ptr = SI->getOperand(1);
if (isa<UndefValue>(Ptr) ||
(isa<ConstantPointerNull>(Ptr) &&
SI->getPointerAddressSpace() == 0)) {
changeToUnreachable(SI, true);
Changed = true;
break;
}
}
}
// Turn invokes that call 'nounwind' functions into ordinary calls.
if (InvokeInst *II = dyn_cast<InvokeInst>(BB->getTerminator())) {
Value *Callee = II->getCalledValue();
if (isa<ConstantPointerNull>(Callee) || isa<UndefValue>(Callee)) {
changeToUnreachable(II, true);
Changed = true;
} else if (II->doesNotThrow() && canSimplifyInvokeNoUnwind(&F)) {
if (II->use_empty() && II->onlyReadsMemory()) {
// jump to the normal destination branch.
BranchInst::Create(II->getNormalDest(), II);
II->getUnwindDest()->removePredecessor(II->getParent());
II->eraseFromParent();
} else
changeToCall(II);
Changed = true;
}
}
Changed |= ConstantFoldTerminator(BB, true);
for (succ_iterator SI = succ_begin(BB), SE = succ_end(BB); SI != SE; ++SI)
if (Reachable.insert(*SI).second)
Worklist.push_back(*SI);
} while (!Worklist.empty());
return Changed;
}
/// removeUnreachableBlocksFromFn - Remove blocks that are not reachable, even
/// if they are in a dead cycle. Return true if a change was made, false
/// otherwise.
bool llvm::removeUnreachableBlocks(Function &F) {
SmallPtrSet<BasicBlock*, 128> Reachable;
bool Changed = markAliveBlocks(F, Reachable);
// If there are unreachable blocks in the CFG...
if (Reachable.size() == F.size())
return Changed;
assert(Reachable.size() < F.size());
NumRemoved += F.size()-Reachable.size();
// Loop over all of the basic blocks that are not reachable, dropping all of
// their internal references...
for (Function::iterator BB = ++F.begin(), E = F.end(); BB != E; ++BB) {
if (Reachable.count(BB))
continue;
for (succ_iterator SI = succ_begin(BB), SE = succ_end(BB); SI != SE; ++SI)
if (Reachable.count(*SI))
(*SI)->removePredecessor(BB);
BB->dropAllReferences();
}
for (Function::iterator I = ++F.begin(); I != F.end();)
if (!Reachable.count(I))
I = F.getBasicBlockList().erase(I);
else
++I;
return true;
}
void llvm::combineMetadata(Instruction *K, const Instruction *J, ArrayRef<unsigned> OrigKnownIDs) {
// HLSL Change Begin - Add known dxil metadata to preserved set.
SmallVector<unsigned, 2> DxilMetadataIDs;
hlsl::DxilMDHelper::GetKnownMetadataIDs(K->getContext(), &DxilMetadataIDs);
SmallVector<unsigned, 8> KnownIDs(std::begin(OrigKnownIDs), std::end(OrigKnownIDs));
std::copy(DxilMetadataIDs.begin(), DxilMetadataIDs.end(), std::back_inserter(KnownIDs));
// HLSL Change End.
SmallVector<std::pair<unsigned, MDNode *>, 4> Metadata;
K->dropUnknownMetadata(KnownIDs);
K->getAllMetadataOtherThanDebugLoc(Metadata);
for (unsigned i = 0, n = Metadata.size(); i < n; ++i) {
unsigned Kind = Metadata[i].first;
MDNode *JMD = J->getMetadata(Kind);
MDNode *KMD = Metadata[i].second;
switch (Kind) {
default:
// HLSL Change - Do not remove dxil metadata. It is combined below with `combineDxilMetadata`.
if (std::find(DxilMetadataIDs.begin(), DxilMetadataIDs.end(), Kind) == DxilMetadataIDs.end())
K->setMetadata(Kind, nullptr); // Remove unknown metadata
break;
case LLVMContext::MD_dbg:
llvm_unreachable("getAllMetadataOtherThanDebugLoc returned a MD_dbg");
case LLVMContext::MD_tbaa:
K->setMetadata(Kind, MDNode::getMostGenericTBAA(JMD, KMD));
break;
case LLVMContext::MD_alias_scope:
K->setMetadata(Kind, MDNode::getMostGenericAliasScope(JMD, KMD));
break;
case LLVMContext::MD_noalias:
K->setMetadata(Kind, MDNode::intersect(JMD, KMD));
break;
case LLVMContext::MD_range:
K->setMetadata(Kind, MDNode::getMostGenericRange(JMD, KMD));
break;
case LLVMContext::MD_fpmath:
K->setMetadata(Kind, MDNode::getMostGenericFPMath(JMD, KMD));
break;
case LLVMContext::MD_invariant_load:
// Only set the !invariant.load if it is present in both instructions.
K->setMetadata(Kind, JMD);
break;
case LLVMContext::MD_nonnull:
// Only set the !nonnull if it is present in both instructions.
K->setMetadata(Kind, JMD);
break;
}
}
// HLSL Change Begin - combine dxil metadata.
hlsl::DxilMDHelper::combineDxilMetadata(K, J);
// HLSL Change End.
}
unsigned llvm::replaceDominatedUsesWith(Value *From, Value *To,
DominatorTree &DT,
const BasicBlockEdge &Root) {
assert(From->getType() == To->getType());
unsigned Count = 0;
for (Value::use_iterator UI = From->use_begin(), UE = From->use_end();
UI != UE; ) {
Use &U = *UI++;
if (DT.dominates(Root, U)) {
U.set(To);
DEBUG(dbgs() << "Replace dominated use of '"
<< From->getName() << "' as "
<< *To << " in " << *U << "\n");
++Count;
}
}
return Count;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/LLVMBuild.txt | ;===- ./lib/Transforms/Utils/LLVMBuild.txt ---------------------*- Conf -*--===;
;
; The LLVM Compiler Infrastructure
;
; This file is distributed under the University of Illinois Open Source
; License. See LICENSE.TXT for details.
;
;===------------------------------------------------------------------------===;
;
; This is an LLVMBuild description file for the components in this subdirectory.
;
; For more information on the LLVMBuild system, please see:
;
; http://llvm.org/docs/LLVMBuild.html
;
;===------------------------------------------------------------------------===;
[component_0]
type = Library
name = TransformUtils
parent = Transforms
required_libraries = Analysis Core IPA Support
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/InlineFunction.cpp | //===- InlineFunction.cpp - Code to perform function inlining -------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements inlining of a function into a call site, resolving
// parameters and the return value as appropriate.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/Cloning.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/CallGraph.h"
#include "llvm/Analysis/CaptureTracking.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/DIBuilder.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/Module.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Support/CommandLine.h"
#include <algorithm>
using namespace llvm;
#if 0 // HLSL Change Starts - option pending
static cl::opt<bool>
EnableNoAliasConversion("enable-noalias-to-md-conversion", cl::init(true),
cl::Hidden,
cl::desc("Convert noalias attributes to metadata during inlining."));
static cl::opt<bool>
PreserveAlignmentAssumptions("preserve-alignment-assumptions-during-inlining",
cl::init(true), cl::Hidden,
cl::desc("Convert align attributes to assumptions during inlining."));
#else
static const bool EnableNoAliasConversion = true;
static const bool PreserveAlignmentAssumptions = true;
#endif // HLSL Change Ends
bool llvm::InlineFunction(CallInst *CI, InlineFunctionInfo &IFI,
bool InsertLifetime) {
return InlineFunction(CallSite(CI), IFI, InsertLifetime);
}
bool llvm::InlineFunction(InvokeInst *II, InlineFunctionInfo &IFI,
bool InsertLifetime) {
return InlineFunction(CallSite(II), IFI, InsertLifetime);
}
namespace {
/// A class for recording information about inlining through an invoke.
class InvokeInliningInfo {
BasicBlock *OuterResumeDest; ///< Destination of the invoke's unwind.
BasicBlock *InnerResumeDest; ///< Destination for the callee's resume.
LandingPadInst *CallerLPad; ///< LandingPadInst associated with the invoke.
PHINode *InnerEHValuesPHI; ///< PHI for EH values from landingpad insts.
SmallVector<Value*, 8> UnwindDestPHIValues;
public:
InvokeInliningInfo(InvokeInst *II)
: OuterResumeDest(II->getUnwindDest()), InnerResumeDest(nullptr),
CallerLPad(nullptr), InnerEHValuesPHI(nullptr) {
// If there are PHI nodes in the unwind destination block, we need to keep
// track of which values came into them from the invoke before removing
// the edge from this block.
llvm::BasicBlock *InvokeBB = II->getParent();
BasicBlock::iterator I = OuterResumeDest->begin();
for (; isa<PHINode>(I); ++I) {
// Save the value to use for this edge.
PHINode *PHI = cast<PHINode>(I);
UnwindDestPHIValues.push_back(PHI->getIncomingValueForBlock(InvokeBB));
}
CallerLPad = cast<LandingPadInst>(I);
}
/// The outer unwind destination is the target of
/// unwind edges introduced for calls within the inlined function.
BasicBlock *getOuterResumeDest() const {
return OuterResumeDest;
}
BasicBlock *getInnerResumeDest();
LandingPadInst *getLandingPadInst() const { return CallerLPad; }
/// Forward the 'resume' instruction to the caller's landing pad block.
/// When the landing pad block has only one predecessor, this is
/// a simple branch. When there is more than one predecessor, we need to
/// split the landing pad block after the landingpad instruction and jump
/// to there.
void forwardResume(ResumeInst *RI,
SmallPtrSetImpl<LandingPadInst*> &InlinedLPads);
/// Add incoming-PHI values to the unwind destination block for the given
/// basic block, using the values for the original invoke's source block.
void addIncomingPHIValuesFor(BasicBlock *BB) const {
addIncomingPHIValuesForInto(BB, OuterResumeDest);
}
void addIncomingPHIValuesForInto(BasicBlock *src, BasicBlock *dest) const {
BasicBlock::iterator I = dest->begin();
for (unsigned i = 0, e = UnwindDestPHIValues.size(); i != e; ++i, ++I) {
PHINode *phi = cast<PHINode>(I);
phi->addIncoming(UnwindDestPHIValues[i], src);
}
}
};
}
/// Get or create a target for the branch from ResumeInsts.
BasicBlock *InvokeInliningInfo::getInnerResumeDest() {
if (InnerResumeDest) return InnerResumeDest;
// Split the landing pad.
BasicBlock::iterator SplitPoint = CallerLPad; ++SplitPoint;
InnerResumeDest =
OuterResumeDest->splitBasicBlock(SplitPoint,
OuterResumeDest->getName() + ".body");
// The number of incoming edges we expect to the inner landing pad.
const unsigned PHICapacity = 2;
// Create corresponding new PHIs for all the PHIs in the outer landing pad.
BasicBlock::iterator InsertPoint = InnerResumeDest->begin();
BasicBlock::iterator I = OuterResumeDest->begin();
for (unsigned i = 0, e = UnwindDestPHIValues.size(); i != e; ++i, ++I) {
PHINode *OuterPHI = cast<PHINode>(I);
PHINode *InnerPHI = PHINode::Create(OuterPHI->getType(), PHICapacity,
OuterPHI->getName() + ".lpad-body",
InsertPoint);
OuterPHI->replaceAllUsesWith(InnerPHI);
InnerPHI->addIncoming(OuterPHI, OuterResumeDest);
}
// Create a PHI for the exception values.
InnerEHValuesPHI = PHINode::Create(CallerLPad->getType(), PHICapacity,
"eh.lpad-body", InsertPoint);
CallerLPad->replaceAllUsesWith(InnerEHValuesPHI);
InnerEHValuesPHI->addIncoming(CallerLPad, OuterResumeDest);
// All done.
return InnerResumeDest;
}
/// Forward the 'resume' instruction to the caller's landing pad block.
/// When the landing pad block has only one predecessor, this is a simple
/// branch. When there is more than one predecessor, we need to split the
/// landing pad block after the landingpad instruction and jump to there.
void InvokeInliningInfo::forwardResume(ResumeInst *RI,
SmallPtrSetImpl<LandingPadInst*> &InlinedLPads) {
BasicBlock *Dest = getInnerResumeDest();
BasicBlock *Src = RI->getParent();
BranchInst::Create(Dest, Src);
// Update the PHIs in the destination. They were inserted in an order which
// makes this work.
addIncomingPHIValuesForInto(Src, Dest);
InnerEHValuesPHI->addIncoming(RI->getOperand(0), Src);
RI->eraseFromParent();
}
/// When we inline a basic block into an invoke,
/// we have to turn all of the calls that can throw into invokes.
/// This function analyze BB to see if there are any calls, and if so,
/// it rewrites them to be invokes that jump to InvokeDest and fills in the PHI
/// nodes in that block with the values specified in InvokeDestPHIValues.
static void HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB,
InvokeInliningInfo &Invoke) {
for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E; ) {
Instruction *I = BBI++;
// We only need to check for function calls: inlined invoke
// instructions require no special handling.
CallInst *CI = dyn_cast<CallInst>(I);
// If this call cannot unwind, don't convert it to an invoke.
// Inline asm calls cannot throw.
if (!CI || CI->doesNotThrow() || isa<InlineAsm>(CI->getCalledValue()))
continue;
// Convert this function call into an invoke instruction. First, split the
// basic block.
BasicBlock *Split = BB->splitBasicBlock(CI, CI->getName()+".noexc");
// Delete the unconditional branch inserted by splitBasicBlock
BB->getInstList().pop_back();
// Create the new invoke instruction.
ImmutableCallSite CS(CI);
SmallVector<Value*, 8> InvokeArgs(CS.arg_begin(), CS.arg_end());
InvokeInst *II = InvokeInst::Create(CI->getCalledValue(), Split,
Invoke.getOuterResumeDest(),
InvokeArgs, CI->getName(), BB);
II->setDebugLoc(CI->getDebugLoc());
II->setCallingConv(CI->getCallingConv());
II->setAttributes(CI->getAttributes());
// Make sure that anything using the call now uses the invoke! This also
// updates the CallGraph if present, because it uses a WeakTrackingVH.
CI->replaceAllUsesWith(II);
// Delete the original call
Split->getInstList().pop_front();
// Update any PHI nodes in the exceptional block to indicate that there is
// now a new entry in them.
Invoke.addIncomingPHIValuesFor(BB);
return;
}
}
/// If we inlined an invoke site, we need to convert calls
/// in the body of the inlined function into invokes.
///
/// II is the invoke instruction being inlined. FirstNewBlock is the first
/// block of the inlined code (the last block is the end of the function),
/// and InlineCodeInfo is information about the code that got inlined.
static void HandleInlinedInvoke(InvokeInst *II, BasicBlock *FirstNewBlock,
ClonedCodeInfo &InlinedCodeInfo) {
BasicBlock *InvokeDest = II->getUnwindDest();
Function *Caller = FirstNewBlock->getParent();
// The inlined code is currently at the end of the function, scan from the
// start of the inlined code to its end, checking for stuff we need to
// rewrite.
InvokeInliningInfo Invoke(II);
// Get all of the inlined landing pad instructions.
SmallPtrSet<LandingPadInst*, 16> InlinedLPads;
for (Function::iterator I = FirstNewBlock, E = Caller->end(); I != E; ++I)
if (InvokeInst *II = dyn_cast<InvokeInst>(I->getTerminator()))
InlinedLPads.insert(II->getLandingPadInst());
// Append the clauses from the outer landing pad instruction into the inlined
// landing pad instructions.
LandingPadInst *OuterLPad = Invoke.getLandingPadInst();
for (LandingPadInst *InlinedLPad : InlinedLPads) {
unsigned OuterNum = OuterLPad->getNumClauses();
InlinedLPad->reserveClauses(OuterNum);
for (unsigned OuterIdx = 0; OuterIdx != OuterNum; ++OuterIdx)
InlinedLPad->addClause(OuterLPad->getClause(OuterIdx));
if (OuterLPad->isCleanup())
InlinedLPad->setCleanup(true);
}
for (Function::iterator BB = FirstNewBlock, E = Caller->end(); BB != E; ++BB){
if (InlinedCodeInfo.ContainsCalls)
HandleCallsInBlockInlinedThroughInvoke(BB, Invoke);
// Forward any resumes that are remaining here.
if (ResumeInst *RI = dyn_cast<ResumeInst>(BB->getTerminator()))
Invoke.forwardResume(RI, InlinedLPads);
}
// Now that everything is happy, we have one final detail. The PHI nodes in
// the exception destination block still have entries due to the original
// invoke instruction. Eliminate these entries (which might even delete the
// PHI node) now.
InvokeDest->removePredecessor(II->getParent());
}
/// When inlining a function that contains noalias scope metadata,
/// this metadata needs to be cloned so that the inlined blocks
/// have different "unqiue scopes" at every call site. Were this not done, then
/// aliasing scopes from a function inlined into a caller multiple times could
/// not be differentiated (and this would lead to miscompiles because the
/// non-aliasing property communicated by the metadata could have
/// call-site-specific control dependencies).
static void CloneAliasScopeMetadata(CallSite CS, ValueToValueMapTy &VMap) {
const Function *CalledFunc = CS.getCalledFunction();
SetVector<const MDNode *> MD;
// Note: We could only clone the metadata if it is already used in the
// caller. I'm omitting that check here because it might confuse
// inter-procedural alias analysis passes. We can revisit this if it becomes
// an efficiency or overhead problem.
for (Function::const_iterator I = CalledFunc->begin(), IE = CalledFunc->end();
I != IE; ++I)
for (BasicBlock::const_iterator J = I->begin(), JE = I->end(); J != JE; ++J) {
if (const MDNode *M = J->getMetadata(LLVMContext::MD_alias_scope))
MD.insert(M);
if (const MDNode *M = J->getMetadata(LLVMContext::MD_noalias))
MD.insert(M);
}
if (MD.empty())
return;
// Walk the existing metadata, adding the complete (perhaps cyclic) chain to
// the set.
SmallVector<const Metadata *, 16> Queue(MD.begin(), MD.end());
while (!Queue.empty()) {
const MDNode *M = cast<MDNode>(Queue.pop_back_val());
for (unsigned i = 0, ie = M->getNumOperands(); i != ie; ++i)
if (const MDNode *M1 = dyn_cast<MDNode>(M->getOperand(i)))
if (MD.insert(M1))
Queue.push_back(M1);
}
// Now we have a complete set of all metadata in the chains used to specify
// the noalias scopes and the lists of those scopes.
SmallVector<TempMDTuple, 16> DummyNodes;
DenseMap<const MDNode *, TrackingMDNodeRef> MDMap;
for (SetVector<const MDNode *>::iterator I = MD.begin(), IE = MD.end();
I != IE; ++I) {
DummyNodes.push_back(MDTuple::getTemporary(CalledFunc->getContext(), None));
MDMap[*I].reset(DummyNodes.back().get());
}
// Create new metadata nodes to replace the dummy nodes, replacing old
// metadata references with either a dummy node or an already-created new
// node.
for (SetVector<const MDNode *>::iterator I = MD.begin(), IE = MD.end();
I != IE; ++I) {
SmallVector<Metadata *, 4> NewOps;
for (unsigned i = 0, ie = (*I)->getNumOperands(); i != ie; ++i) {
const Metadata *V = (*I)->getOperand(i);
if (const MDNode *M = dyn_cast<MDNode>(V))
NewOps.push_back(MDMap[M]);
else
NewOps.push_back(const_cast<Metadata *>(V));
}
MDNode *NewM = MDNode::get(CalledFunc->getContext(), NewOps);
MDTuple *TempM = cast<MDTuple>(MDMap[*I]);
assert(TempM->isTemporary() && "Expected temporary node");
TempM->replaceAllUsesWith(NewM);
}
// Now replace the metadata in the new inlined instructions with the
// repacements from the map.
for (ValueToValueMapTy::iterator VMI = VMap.begin(), VMIE = VMap.end();
VMI != VMIE; ++VMI) {
if (!VMI->second)
continue;
Instruction *NI = dyn_cast<Instruction>(VMI->second);
if (!NI)
continue;
if (MDNode *M = NI->getMetadata(LLVMContext::MD_alias_scope)) {
MDNode *NewMD = MDMap[M];
// If the call site also had alias scope metadata (a list of scopes to
// which instructions inside it might belong), propagate those scopes to
// the inlined instructions.
if (MDNode *CSM =
CS.getInstruction()->getMetadata(LLVMContext::MD_alias_scope))
NewMD = MDNode::concatenate(NewMD, CSM);
NI->setMetadata(LLVMContext::MD_alias_scope, NewMD);
} else if (NI->mayReadOrWriteMemory()) {
if (MDNode *M =
CS.getInstruction()->getMetadata(LLVMContext::MD_alias_scope))
NI->setMetadata(LLVMContext::MD_alias_scope, M);
}
if (MDNode *M = NI->getMetadata(LLVMContext::MD_noalias)) {
MDNode *NewMD = MDMap[M];
// If the call site also had noalias metadata (a list of scopes with
// which instructions inside it don't alias), propagate those scopes to
// the inlined instructions.
if (MDNode *CSM =
CS.getInstruction()->getMetadata(LLVMContext::MD_noalias))
NewMD = MDNode::concatenate(NewMD, CSM);
NI->setMetadata(LLVMContext::MD_noalias, NewMD);
} else if (NI->mayReadOrWriteMemory()) {
if (MDNode *M = CS.getInstruction()->getMetadata(LLVMContext::MD_noalias))
NI->setMetadata(LLVMContext::MD_noalias, M);
}
}
}
/// If the inlined function has noalias arguments,
/// then add new alias scopes for each noalias argument, tag the mapped noalias
/// parameters with noalias metadata specifying the new scope, and tag all
/// non-derived loads, stores and memory intrinsics with the new alias scopes.
static void AddAliasScopeMetadata(CallSite CS, ValueToValueMapTy &VMap,
const DataLayout &DL, AliasAnalysis *AA) {
if (!EnableNoAliasConversion)
return;
const Function *CalledFunc = CS.getCalledFunction();
SmallVector<const Argument *, 4> NoAliasArgs;
for (Function::const_arg_iterator I = CalledFunc->arg_begin(),
E = CalledFunc->arg_end(); I != E; ++I) {
if (I->hasNoAliasAttr() && !I->hasNUses(0))
NoAliasArgs.push_back(I);
}
if (NoAliasArgs.empty())
return;
// To do a good job, if a noalias variable is captured, we need to know if
// the capture point dominates the particular use we're considering.
DominatorTree DT;
DT.recalculate(const_cast<Function&>(*CalledFunc));
// noalias indicates that pointer values based on the argument do not alias
// pointer values which are not based on it. So we add a new "scope" for each
// noalias function argument. Accesses using pointers based on that argument
// become part of that alias scope, accesses using pointers not based on that
// argument are tagged as noalias with that scope.
DenseMap<const Argument *, MDNode *> NewScopes;
MDBuilder MDB(CalledFunc->getContext());
// Create a new scope domain for this function.
MDNode *NewDomain =
MDB.createAnonymousAliasScopeDomain(CalledFunc->getName());
for (unsigned i = 0, e = NoAliasArgs.size(); i != e; ++i) {
const Argument *A = NoAliasArgs[i];
std::string Name = CalledFunc->getName();
if (A->hasName()) {
Name += ": %";
Name += A->getName();
} else {
Name += ": argument ";
Name += utostr(i);
}
// Note: We always create a new anonymous root here. This is true regardless
// of the linkage of the callee because the aliasing "scope" is not just a
// property of the callee, but also all control dependencies in the caller.
MDNode *NewScope = MDB.createAnonymousAliasScope(NewDomain, Name);
NewScopes.insert(std::make_pair(A, NewScope));
}
// Iterate over all new instructions in the map; for all memory-access
// instructions, add the alias scope metadata.
for (ValueToValueMapTy::iterator VMI = VMap.begin(), VMIE = VMap.end();
VMI != VMIE; ++VMI) {
if (const Instruction *I = dyn_cast<Instruction>(VMI->first)) {
if (!VMI->second)
continue;
Instruction *NI = dyn_cast<Instruction>(VMI->second);
if (!NI)
continue;
bool IsArgMemOnlyCall = false, IsFuncCall = false;
SmallVector<const Value *, 2> PtrArgs;
if (const LoadInst *LI = dyn_cast<LoadInst>(I))
PtrArgs.push_back(LI->getPointerOperand());
else if (const StoreInst *SI = dyn_cast<StoreInst>(I))
PtrArgs.push_back(SI->getPointerOperand());
else if (const VAArgInst *VAAI = dyn_cast<VAArgInst>(I))
PtrArgs.push_back(VAAI->getPointerOperand());
else if (const AtomicCmpXchgInst *CXI = dyn_cast<AtomicCmpXchgInst>(I))
PtrArgs.push_back(CXI->getPointerOperand());
else if (const AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(I))
PtrArgs.push_back(RMWI->getPointerOperand());
else if (ImmutableCallSite ICS = ImmutableCallSite(I)) {
// If we know that the call does not access memory, then we'll still
// know that about the inlined clone of this call site, and we don't
// need to add metadata.
if (ICS.doesNotAccessMemory())
continue;
IsFuncCall = true;
if (AA) {
AliasAnalysis::ModRefBehavior MRB = AA->getModRefBehavior(ICS);
if (MRB == AliasAnalysis::OnlyAccessesArgumentPointees ||
MRB == AliasAnalysis::OnlyReadsArgumentPointees)
IsArgMemOnlyCall = true;
}
for (ImmutableCallSite::arg_iterator AI = ICS.arg_begin(),
AE = ICS.arg_end(); AI != AE; ++AI) {
// We need to check the underlying objects of all arguments, not just
// the pointer arguments, because we might be passing pointers as
// integers, etc.
// However, if we know that the call only accesses pointer arguments,
// then we only need to check the pointer arguments.
if (IsArgMemOnlyCall && !(*AI)->getType()->isPointerTy())
continue;
PtrArgs.push_back(*AI);
}
}
// If we found no pointers, then this instruction is not suitable for
// pairing with an instruction to receive aliasing metadata.
// However, if this is a call, this we might just alias with none of the
// noalias arguments.
if (PtrArgs.empty() && !IsFuncCall)
continue;
// It is possible that there is only one underlying object, but you
// need to go through several PHIs to see it, and thus could be
// repeated in the Objects list.
SmallPtrSet<const Value *, 4> ObjSet;
SmallVector<Metadata *, 4> Scopes, NoAliases;
SmallSetVector<const Argument *, 4> NAPtrArgs;
for (unsigned i = 0, ie = PtrArgs.size(); i != ie; ++i) {
SmallVector<Value *, 4> Objects;
GetUnderlyingObjects(const_cast<Value*>(PtrArgs[i]),
Objects, DL, /* MaxLookup = */ 0);
for (Value *O : Objects)
ObjSet.insert(O);
}
// Figure out if we're derived from anything that is not a noalias
// argument.
bool CanDeriveViaCapture = false, UsesAliasingPtr = false;
for (const Value *V : ObjSet) {
// Is this value a constant that cannot be derived from any pointer
// value (we need to exclude constant expressions, for example, that
// are formed from arithmetic on global symbols).
bool IsNonPtrConst = isa<ConstantInt>(V) || isa<ConstantFP>(V) ||
isa<ConstantPointerNull>(V) ||
isa<ConstantDataVector>(V) || isa<UndefValue>(V);
if (IsNonPtrConst)
continue;
// If this is anything other than a noalias argument, then we cannot
// completely describe the aliasing properties using alias.scope
// metadata (and, thus, won't add any).
if (const Argument *A = dyn_cast<Argument>(V)) {
if (!A->hasNoAliasAttr())
UsesAliasingPtr = true;
} else {
UsesAliasingPtr = true;
}
// If this is not some identified function-local object (which cannot
// directly alias a noalias argument), or some other argument (which,
// by definition, also cannot alias a noalias argument), then we could
// alias a noalias argument that has been captured).
if (!isa<Argument>(V) &&
!isIdentifiedFunctionLocal(const_cast<Value*>(V)))
CanDeriveViaCapture = true;
}
// A function call can always get captured noalias pointers (via other
// parameters, globals, etc.).
if (IsFuncCall && !IsArgMemOnlyCall)
CanDeriveViaCapture = true;
// First, we want to figure out all of the sets with which we definitely
// don't alias. Iterate over all noalias set, and add those for which:
// 1. The noalias argument is not in the set of objects from which we
// definitely derive.
// 2. The noalias argument has not yet been captured.
// An arbitrary function that might load pointers could see captured
// noalias arguments via other noalias arguments or globals, and so we
// must always check for prior capture.
for (const Argument *A : NoAliasArgs) {
if (!ObjSet.count(A) && (!CanDeriveViaCapture ||
// It might be tempting to skip the
// PointerMayBeCapturedBefore check if
// A->hasNoCaptureAttr() is true, but this is
// incorrect because nocapture only guarantees
// that no copies outlive the function, not
// that the value cannot be locally captured.
!PointerMayBeCapturedBefore(A,
/* ReturnCaptures */ false,
/* StoreCaptures */ false, I, &DT)))
NoAliases.push_back(NewScopes[A]);
}
if (!NoAliases.empty())
NI->setMetadata(LLVMContext::MD_noalias,
MDNode::concatenate(
NI->getMetadata(LLVMContext::MD_noalias),
MDNode::get(CalledFunc->getContext(), NoAliases)));
// Next, we want to figure out all of the sets to which we might belong.
// We might belong to a set if the noalias argument is in the set of
// underlying objects. If there is some non-noalias argument in our list
// of underlying objects, then we cannot add a scope because the fact
// that some access does not alias with any set of our noalias arguments
// cannot itself guarantee that it does not alias with this access
// (because there is some pointer of unknown origin involved and the
// other access might also depend on this pointer). We also cannot add
// scopes to arbitrary functions unless we know they don't access any
// non-parameter pointer-values.
bool CanAddScopes = !UsesAliasingPtr;
if (CanAddScopes && IsFuncCall)
CanAddScopes = IsArgMemOnlyCall;
if (CanAddScopes)
for (const Argument *A : NoAliasArgs) {
if (ObjSet.count(A))
Scopes.push_back(NewScopes[A]);
}
if (!Scopes.empty())
NI->setMetadata(
LLVMContext::MD_alias_scope,
MDNode::concatenate(NI->getMetadata(LLVMContext::MD_alias_scope),
MDNode::get(CalledFunc->getContext(), Scopes)));
}
}
}
/// If the inlined function has non-byval align arguments, then
/// add @llvm.assume-based alignment assumptions to preserve this information.
static void AddAlignmentAssumptions(CallSite CS, InlineFunctionInfo &IFI) {
if (!PreserveAlignmentAssumptions)
return;
auto &DL = CS.getCaller()->getParent()->getDataLayout();
// To avoid inserting redundant assumptions, we should check for assumptions
// already in the caller. To do this, we might need a DT of the caller.
DominatorTree DT;
bool DTCalculated = false;
Function *CalledFunc = CS.getCalledFunction();
for (Function::arg_iterator I = CalledFunc->arg_begin(),
E = CalledFunc->arg_end();
I != E; ++I) {
unsigned Align = I->getType()->isPointerTy() ? I->getParamAlignment() : 0;
if (Align && !I->hasByValOrInAllocaAttr() && !I->hasNUses(0)) {
if (!DTCalculated) {
DT.recalculate(const_cast<Function&>(*CS.getInstruction()->getParent()
->getParent()));
DTCalculated = true;
}
// If we can already prove the asserted alignment in the context of the
// caller, then don't bother inserting the assumption.
Value *Arg = CS.getArgument(I->getArgNo());
if (getKnownAlignment(Arg, DL, CS.getInstruction(),
&IFI.ACT->getAssumptionCache(*CalledFunc),
&DT) >= Align)
continue;
IRBuilder<>(CS.getInstruction())
.CreateAlignmentAssumption(DL, Arg, Align);
}
}
}
/// Once we have cloned code over from a callee into the caller,
/// update the specified callgraph to reflect the changes we made.
/// Note that it's possible that not all code was copied over, so only
/// some edges of the callgraph may remain.
static void UpdateCallGraphAfterInlining(CallSite CS,
Function::iterator FirstNewBlock,
ValueToValueMapTy &VMap,
InlineFunctionInfo &IFI) {
CallGraph &CG = *IFI.CG;
const Function *Caller = CS.getInstruction()->getParent()->getParent();
const Function *Callee = CS.getCalledFunction();
CallGraphNode *CalleeNode = CG[Callee];
CallGraphNode *CallerNode = CG[Caller];
// Since we inlined some uninlined call sites in the callee into the caller,
// add edges from the caller to all of the callees of the callee.
CallGraphNode::iterator I = CalleeNode->begin(), E = CalleeNode->end();
// Consider the case where CalleeNode == CallerNode.
CallGraphNode::CalledFunctionsVector CallCache;
if (CalleeNode == CallerNode) {
CallCache.assign(I, E);
I = CallCache.begin();
E = CallCache.end();
}
for (; I != E; ++I) {
const Value *OrigCall = I->first;
ValueToValueMapTy::iterator VMI = VMap.find(OrigCall);
// Only copy the edge if the call was inlined!
if (VMI == VMap.end() || VMI->second == nullptr)
continue;
// If the call was inlined, but then constant folded, there is no edge to
// add. Check for this case.
Instruction *NewCall = dyn_cast<Instruction>(VMI->second);
if (!NewCall)
continue;
// We do not treat intrinsic calls like real function calls because we
// expect them to become inline code; do not add an edge for an intrinsic.
CallSite CS = CallSite(NewCall);
if (CS && CS.getCalledFunction() && CS.getCalledFunction()->isIntrinsic())
continue;
// Remember that this call site got inlined for the client of
// InlineFunction.
IFI.InlinedCalls.push_back(NewCall);
// It's possible that inlining the callsite will cause it to go from an
// indirect to a direct call by resolving a function pointer. If this
// happens, set the callee of the new call site to a more precise
// destination. This can also happen if the call graph node of the caller
// was just unnecessarily imprecise.
if (!I->second->getFunction())
if (Function *F = CallSite(NewCall).getCalledFunction()) {
// Indirect call site resolved to direct call.
CallerNode->addCalledFunction(CallSite(NewCall), CG[F]);
continue;
}
CallerNode->addCalledFunction(CallSite(NewCall), I->second);
}
// Update the call graph by deleting the edge from Callee to Caller. We must
// do this after the loop above in case Caller and Callee are the same.
CallerNode->removeCallEdgeFor(CS);
}
static void HandleByValArgumentInit(Value *Dst, Value *Src, Module *M,
BasicBlock *InsertBlock,
InlineFunctionInfo &IFI) {
Type *AggTy = cast<PointerType>(Src->getType())->getElementType();
IRBuilder<> Builder(InsertBlock->begin());
Value *Size = Builder.getInt64(M->getDataLayout().getTypeStoreSize(AggTy));
// Always generate a memcpy of alignment 1 here because we don't know
// the alignment of the src pointer. Other optimizations can infer
// better alignment.
Builder.CreateMemCpy(Dst, Src, Size, /*Align=*/1);
}
/// When inlining a call site that has a byval argument,
/// we have to make the implicit memcpy explicit by adding it.
static Value *HandleByValArgument(Value *Arg, Instruction *TheCall,
const Function *CalledFunc,
InlineFunctionInfo &IFI,
unsigned ByValAlignment) {
PointerType *ArgTy = cast<PointerType>(Arg->getType());
Type *AggTy = ArgTy->getElementType();
Function *Caller = TheCall->getParent()->getParent();
// If the called function is readonly, then it could not mutate the caller's
// copy of the byval'd memory. In this case, it is safe to elide the copy and
// temporary.
if (CalledFunc->onlyReadsMemory()) {
// If the byval argument has a specified alignment that is greater than the
// passed in pointer, then we either have to round up the input pointer or
// give up on this transformation.
if (ByValAlignment <= 1) // 0 = unspecified, 1 = no particular alignment.
return Arg;
const DataLayout &DL = Caller->getParent()->getDataLayout();
// If the pointer is already known to be sufficiently aligned, or if we can
// round it up to a larger alignment, then we don't need a temporary.
if (getOrEnforceKnownAlignment(Arg, ByValAlignment, DL, TheCall,
&IFI.ACT->getAssumptionCache(*Caller)) >=
ByValAlignment)
return Arg;
// Otherwise, we have to make a memcpy to get a safe alignment. This is bad
// for code quality, but rarely happens and is required for correctness.
}
// Create the alloca. If we have DataLayout, use nice alignment.
unsigned Align =
Caller->getParent()->getDataLayout().getPrefTypeAlignment(AggTy);
// If the byval had an alignment specified, we *must* use at least that
// alignment, as it is required by the byval argument (and uses of the
// pointer inside the callee).
Align = std::max(Align, ByValAlignment);
Value *NewAlloca = new AllocaInst(AggTy, nullptr, Align, Arg->getName(),
&*Caller->begin()->begin());
IFI.StaticAllocas.push_back(cast<AllocaInst>(NewAlloca));
// Uses of the argument in the function should use our new alloca
// instead.
return NewAlloca;
}
// Check whether this Value is used by a lifetime intrinsic.
static bool isUsedByLifetimeMarker(Value *V) {
for (User *U : V->users()) {
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(U)) {
switch (II->getIntrinsicID()) {
default: break;
case Intrinsic::lifetime_start:
case Intrinsic::lifetime_end:
return true;
}
}
}
return false;
}
// Check whether the given alloca already has
// lifetime.start or lifetime.end intrinsics.
static bool hasLifetimeMarkers(AllocaInst *AI) {
Type *Ty = AI->getType();
Type *Int8PtrTy = Type::getInt8PtrTy(Ty->getContext(),
Ty->getPointerAddressSpace());
if (Ty == Int8PtrTy)
return isUsedByLifetimeMarker(AI);
// Do a scan to find all the casts to i8*.
for (User *U : AI->users()) {
if (U->getType() != Int8PtrTy) continue;
if (U->stripPointerCasts() != AI) continue;
if (isUsedByLifetimeMarker(U))
return true;
}
return false;
}
/// Rebuild the entire inlined-at chain for this instruction so that the top of
/// the chain now is inlined-at the new call site.
static DebugLoc
updateInlinedAtInfo(DebugLoc DL, DILocation *InlinedAtNode, LLVMContext &Ctx,
DenseMap<const DILocation *, DILocation *> &IANodes) {
SmallVector<DILocation *, 3> InlinedAtLocations;
DILocation *Last = InlinedAtNode;
DILocation *CurInlinedAt = DL;
// Gather all the inlined-at nodes
while (DILocation *IA = CurInlinedAt->getInlinedAt()) {
// Skip any we've already built nodes for
if (DILocation *Found = IANodes[IA]) {
Last = Found;
break;
}
InlinedAtLocations.push_back(IA);
CurInlinedAt = IA;
}
// Starting from the top, rebuild the nodes to point to the new inlined-at
// location (then rebuilding the rest of the chain behind it) and update the
// map of already-constructed inlined-at nodes.
for (auto I = InlinedAtLocations.rbegin(), E = InlinedAtLocations.rend();
I != E; ++I) {
const DILocation *MD = *I;
Last = IANodes[MD] = DILocation::getDistinct(
Ctx, MD->getLine(), MD->getColumn(), MD->getScope(), Last);
}
// And finally create the normal location for this instruction, referring to
// the new inlined-at chain.
return DebugLoc::get(DL.getLine(), DL.getCol(), DL.getScope(), Last);
}
/// Update inlined instructions' line numbers to
/// to encode location where these instructions are inlined.
static void fixupLineNumbers(Function *Fn, Function::iterator FI,
Instruction *TheCall) {
DebugLoc TheCallDL = TheCall->getDebugLoc();
#if 0 // HLSL Change
if (!TheCallDL)
return;
#else // HLSL Change - Begin
// Global variable initialization code gets inlined but the call inst doesn't
// get a location. Fix it here by giving it a dummy location so the debug
// info is well-formed.
if (!TheCallDL) {
// If no debug metadata, don't bother trying to find the subprog
if (!getDebugMetadataVersionFromModule(*Fn->getParent()))
return;
if (DISubprogram *Subprogram = getDISubprogram(Fn)) {
// Just give it the submodule's line, so it doesn't have line number 0
TheCallDL = DebugLoc(llvm::DILocation::get(Fn->getContext(), Subprogram->getLine(), 0, Subprogram));
TheCall->setDebugLoc(TheCallDL);
}
else {
return;
}
}
#endif // HLSL Change - End
auto &Ctx = Fn->getContext();
DILocation *InlinedAtNode = TheCallDL;
// Create a unique call site, not to be confused with any other call from the
// same location.
InlinedAtNode = DILocation::getDistinct(
Ctx, InlinedAtNode->getLine(), InlinedAtNode->getColumn(),
InlinedAtNode->getScope(), InlinedAtNode->getInlinedAt());
// Cache the inlined-at nodes as they're built so they are reused, without
// this every instruction's inlined-at chain would become distinct from each
// other.
DenseMap<const DILocation *, DILocation *> IANodes;
for (; FI != Fn->end(); ++FI) {
for (BasicBlock::iterator BI = FI->begin(), BE = FI->end();
BI != BE; ++BI) {
DebugLoc DL = BI->getDebugLoc();
if (!DL) {
// If the inlined instruction has no line number, make it look as if it
// originates from the call location. This is important for
// ((__always_inline__, __nodebug__)) functions which must use caller
// location for all instructions in their function body.
// Don't update static allocas, as they may get moved later.
if (auto *AI = dyn_cast<AllocaInst>(BI))
if (isa<Constant>(AI->getArraySize()))
continue;
BI->setDebugLoc(TheCallDL);
} else {
BI->setDebugLoc(updateInlinedAtInfo(DL, InlinedAtNode, BI->getContext(), IANodes));
}
}
}
}
/// This function inlines the called function into the basic block of the
/// caller. This returns false if it is not possible to inline this call.
/// The program is still in a well defined state if this occurs though.
///
/// Note that this only does one level of inlining. For example, if the
/// instruction 'call B' is inlined, and 'B' calls 'C', then the call to 'C' now
/// exists in the instruction stream. Similarly this will inline a recursive
/// function by one level.
bool llvm::InlineFunction(CallSite CS, InlineFunctionInfo &IFI,
bool InsertLifetime) {
Instruction *TheCall = CS.getInstruction();
assert(TheCall->getParent() && TheCall->getParent()->getParent() &&
"Instruction not in function!");
// If IFI has any state in it, zap it before we fill it in.
IFI.reset();
const Function *CalledFunc = CS.getCalledFunction();
if (!CalledFunc || // Can't inline external function or indirect
CalledFunc->isDeclaration() || // call, or call to a vararg function!
CalledFunc->getFunctionType()->isVarArg()) return false;
// If the call to the callee cannot throw, set the 'nounwind' flag on any
// calls that we inline.
bool MarkNoUnwind = CS.doesNotThrow();
BasicBlock *OrigBB = TheCall->getParent();
Function *Caller = OrigBB->getParent();
// GC poses two hazards to inlining, which only occur when the callee has GC:
// 1. If the caller has no GC, then the callee's GC must be propagated to the
// caller.
// 2. If the caller has a differing GC, it is invalid to inline.
if (CalledFunc->hasGC()) {
if (!Caller->hasGC())
Caller->setGC(CalledFunc->getGC());
else if (CalledFunc->getGC() != Caller->getGC())
return false;
}
// Get the personality function from the callee if it contains a landing pad.
Constant *CalledPersonality =
CalledFunc->hasPersonalityFn() ? CalledFunc->getPersonalityFn() : nullptr;
// Find the personality function used by the landing pads of the caller. If it
// exists, then check to see that it matches the personality function used in
// the callee.
Constant *CallerPersonality =
Caller->hasPersonalityFn() ? Caller->getPersonalityFn() : nullptr;
if (CalledPersonality) {
if (!CallerPersonality)
Caller->setPersonalityFn(CalledPersonality);
// If the personality functions match, then we can perform the
// inlining. Otherwise, we can't inline.
// TODO: This isn't 100% true. Some personality functions are proper
// supersets of others and can be used in place of the other.
else if (CalledPersonality != CallerPersonality)
return false;
}
// Get an iterator to the last basic block in the function, which will have
// the new function inlined after it.
Function::iterator LastBlock = &Caller->back();
// Make sure to capture all of the return instructions from the cloned
// function.
SmallVector<ReturnInst*, 8> Returns;
ClonedCodeInfo InlinedFunctionInfo;
Function::iterator FirstNewBlock;
{ // Scope to destroy VMap after cloning.
ValueToValueMapTy VMap;
// Keep a list of pair (dst, src) to emit byval initializations.
SmallVector<std::pair<Value*, Value*>, 4> ByValInit;
auto &DL = Caller->getParent()->getDataLayout();
assert(CalledFunc->arg_size() == CS.arg_size() &&
"No varargs calls can be inlined!");
// Calculate the vector of arguments to pass into the function cloner, which
// matches up the formal to the actual argument values.
CallSite::arg_iterator AI = CS.arg_begin();
unsigned ArgNo = 0;
for (Function::const_arg_iterator I = CalledFunc->arg_begin(),
E = CalledFunc->arg_end(); I != E; ++I, ++AI, ++ArgNo) {
Value *ActualArg = *AI;
// When byval arguments actually inlined, we need to make the copy implied
// by them explicit. However, we don't do this if the callee is readonly
// or readnone, because the copy would be unneeded: the callee doesn't
// modify the struct.
if (CS.isByValArgument(ArgNo)) {
ActualArg = HandleByValArgument(ActualArg, TheCall, CalledFunc, IFI,
CalledFunc->getParamAlignment(ArgNo+1));
if (ActualArg != *AI)
ByValInit.push_back(std::make_pair(ActualArg, (Value*) *AI));
}
VMap[I] = ActualArg;
}
// Add alignment assumptions if necessary. We do this before the inlined
// instructions are actually cloned into the caller so that we can easily
// check what will be known at the start of the inlined code.
AddAlignmentAssumptions(CS, IFI);
// We want the inliner to prune the code as it copies. We would LOVE to
// have no dead or constant instructions leftover after inlining occurs
// (which can happen, e.g., because an argument was constant), but we'll be
// happy with whatever the cloner can do.
CloneAndPruneFunctionInto(Caller, CalledFunc, VMap,
/*ModuleLevelChanges=*/false, Returns, ".i",
&InlinedFunctionInfo, TheCall);
// Remember the first block that is newly cloned over.
FirstNewBlock = LastBlock; ++FirstNewBlock;
// Inject byval arguments initialization.
for (std::pair<Value*, Value*> &Init : ByValInit)
HandleByValArgumentInit(Init.first, Init.second, Caller->getParent(),
FirstNewBlock, IFI);
// Update the callgraph if requested.
if (IFI.CG)
UpdateCallGraphAfterInlining(CS, FirstNewBlock, VMap, IFI);
// Update inlined instructions' line number information.
fixupLineNumbers(Caller, FirstNewBlock, TheCall);
// Clone existing noalias metadata if necessary.
CloneAliasScopeMetadata(CS, VMap);
// Add noalias metadata if necessary.
AddAliasScopeMetadata(CS, VMap, DL, IFI.AA);
// FIXME: We could register any cloned assumptions instead of clearing the
// whole function's cache.
if (IFI.ACT)
IFI.ACT->getAssumptionCache(*Caller).clear();
}
// If there are any alloca instructions in the block that used to be the entry
// block for the callee, move them to the entry block of the caller. First
// calculate which instruction they should be inserted before. We insert the
// instructions at the end of the current alloca list.
{
BasicBlock::iterator InsertPoint = Caller->begin()->begin();
for (BasicBlock::iterator I = FirstNewBlock->begin(),
E = FirstNewBlock->end(); I != E; ) {
AllocaInst *AI = dyn_cast<AllocaInst>(I++);
if (!AI) continue;
// If the alloca is now dead, remove it. This often occurs due to code
// specialization.
if (AI->use_empty()) {
AI->eraseFromParent();
continue;
}
if (!isa<Constant>(AI->getArraySize()))
continue;
// Keep track of the static allocas that we inline into the caller.
IFI.StaticAllocas.push_back(AI);
// Scan for the block of allocas that we can move over, and move them
// all at once.
while (isa<AllocaInst>(I) &&
isa<Constant>(cast<AllocaInst>(I)->getArraySize())) {
IFI.StaticAllocas.push_back(cast<AllocaInst>(I));
++I;
}
// Transfer all of the allocas over in a block. Using splice means
// that the instructions aren't removed from the symbol table, then
// reinserted.
Caller->getEntryBlock().getInstList().splice(InsertPoint,
FirstNewBlock->getInstList(),
AI, I);
}
// Move any dbg.declares describing the allocas into the entry basic block.
DIBuilder DIB(*Caller->getParent());
for (auto &AI : IFI.StaticAllocas)
replaceDbgDeclareForAlloca(AI, AI, DIB, /*Deref=*/false);
}
bool InlinedMustTailCalls = false;
if (InlinedFunctionInfo.ContainsCalls) {
CallInst::TailCallKind CallSiteTailKind = CallInst::TCK_None;
if (CallInst *CI = dyn_cast<CallInst>(TheCall))
CallSiteTailKind = CI->getTailCallKind();
for (Function::iterator BB = FirstNewBlock, E = Caller->end(); BB != E;
++BB) {
for (Instruction &I : *BB) {
CallInst *CI = dyn_cast<CallInst>(&I);
if (!CI)
continue;
// We need to reduce the strength of any inlined tail calls. For
// musttail, we have to avoid introducing potential unbounded stack
// growth. For example, if functions 'f' and 'g' are mutually recursive
// with musttail, we can inline 'g' into 'f' so long as we preserve
// musttail on the cloned call to 'f'. If either the inlined call site
// or the cloned call site is *not* musttail, the program already has
// one frame of stack growth, so it's safe to remove musttail. Here is
// a table of example transformations:
//
// f -> musttail g -> musttail f ==> f -> musttail f
// f -> musttail g -> tail f ==> f -> tail f
// f -> g -> musttail f ==> f -> f
// f -> g -> tail f ==> f -> f
CallInst::TailCallKind ChildTCK = CI->getTailCallKind();
ChildTCK = std::min(CallSiteTailKind, ChildTCK);
CI->setTailCallKind(ChildTCK);
InlinedMustTailCalls |= CI->isMustTailCall();
// Calls inlined through a 'nounwind' call site should be marked
// 'nounwind'.
if (MarkNoUnwind)
CI->setDoesNotThrow();
}
}
}
// Leave lifetime markers for the static alloca's, scoping them to the
// function we just inlined.
if (InsertLifetime && !IFI.StaticAllocas.empty()) {
IRBuilder<> builder(FirstNewBlock->begin());
for (unsigned ai = 0, ae = IFI.StaticAllocas.size(); ai != ae; ++ai) {
AllocaInst *AI = IFI.StaticAllocas[ai];
// If the alloca is already scoped to something smaller than the whole
// function then there's no need to add redundant, less accurate markers.
if (hasLifetimeMarkers(AI))
continue;
// Try to determine the size of the allocation.
ConstantInt *AllocaSize = nullptr;
if (ConstantInt *AIArraySize =
dyn_cast<ConstantInt>(AI->getArraySize())) {
auto &DL = Caller->getParent()->getDataLayout();
Type *AllocaType = AI->getAllocatedType();
uint64_t AllocaTypeSize = DL.getTypeAllocSize(AllocaType);
uint64_t AllocaArraySize = AIArraySize->getLimitedValue();
// Don't add markers for zero-sized allocas.
if (AllocaArraySize == 0)
continue;
// Check that array size doesn't saturate uint64_t and doesn't
// overflow when it's multiplied by type size.
if (AllocaArraySize != ~0ULL &&
UINT64_MAX / AllocaArraySize >= AllocaTypeSize) {
AllocaSize = ConstantInt::get(Type::getInt64Ty(AI->getContext()),
AllocaArraySize * AllocaTypeSize);
}
}
builder.CreateLifetimeStart(AI, AllocaSize);
for (ReturnInst *RI : Returns) {
// Don't insert llvm.lifetime.end calls between a musttail call and a
// return. The return kills all local allocas.
if (InlinedMustTailCalls &&
RI->getParent()->getTerminatingMustTailCall())
continue;
IRBuilder<>(RI).CreateLifetimeEnd(AI, AllocaSize);
}
}
}
// If the inlined code contained dynamic alloca instructions, wrap the inlined
// code with llvm.stacksave/llvm.stackrestore intrinsics.
if (InlinedFunctionInfo.ContainsDynamicAllocas) {
Module *M = Caller->getParent();
// Get the two intrinsics we care about.
Function *StackSave = Intrinsic::getDeclaration(M, Intrinsic::stacksave);
Function *StackRestore=Intrinsic::getDeclaration(M,Intrinsic::stackrestore);
// Insert the llvm.stacksave.
CallInst *SavedPtr = IRBuilder<>(FirstNewBlock, FirstNewBlock->begin())
.CreateCall(StackSave, {}, "savedstack");
// Insert a call to llvm.stackrestore before any return instructions in the
// inlined function.
for (ReturnInst *RI : Returns) {
// Don't insert llvm.stackrestore calls between a musttail call and a
// return. The return will restore the stack pointer.
if (InlinedMustTailCalls && RI->getParent()->getTerminatingMustTailCall())
continue;
IRBuilder<>(RI).CreateCall(StackRestore, SavedPtr);
}
}
// If we are inlining for an invoke instruction, we must make sure to rewrite
// any call instructions into invoke instructions.
if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall))
HandleInlinedInvoke(II, FirstNewBlock, InlinedFunctionInfo);
// Handle any inlined musttail call sites. In order for a new call site to be
// musttail, the source of the clone and the inlined call site must have been
// musttail. Therefore it's safe to return without merging control into the
// phi below.
if (InlinedMustTailCalls) {
// Check if we need to bitcast the result of any musttail calls.
Type *NewRetTy = Caller->getReturnType();
bool NeedBitCast = !TheCall->use_empty() && TheCall->getType() != NewRetTy;
// Handle the returns preceded by musttail calls separately.
SmallVector<ReturnInst *, 8> NormalReturns;
for (ReturnInst *RI : Returns) {
CallInst *ReturnedMustTail =
RI->getParent()->getTerminatingMustTailCall();
if (!ReturnedMustTail) {
NormalReturns.push_back(RI);
continue;
}
if (!NeedBitCast)
continue;
// Delete the old return and any preceding bitcast.
BasicBlock *CurBB = RI->getParent();
auto *OldCast = dyn_cast_or_null<BitCastInst>(RI->getReturnValue());
RI->eraseFromParent();
if (OldCast)
OldCast->eraseFromParent();
// Insert a new bitcast and return with the right type.
IRBuilder<> Builder(CurBB);
Builder.CreateRet(Builder.CreateBitCast(ReturnedMustTail, NewRetTy));
}
// Leave behind the normal returns so we can merge control flow.
std::swap(Returns, NormalReturns);
}
// If we cloned in _exactly one_ basic block, and if that block ends in a
// return instruction, we splice the body of the inlined callee directly into
// the calling basic block.
if (Returns.size() == 1 && std::distance(FirstNewBlock, Caller->end()) == 1) {
// Move all of the instructions right before the call.
OrigBB->getInstList().splice(TheCall, FirstNewBlock->getInstList(),
FirstNewBlock->begin(), FirstNewBlock->end());
// Remove the cloned basic block.
Caller->getBasicBlockList().pop_back();
// If the call site was an invoke instruction, add a branch to the normal
// destination.
if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall)) {
BranchInst *NewBr = BranchInst::Create(II->getNormalDest(), TheCall);
NewBr->setDebugLoc(Returns[0]->getDebugLoc());
}
// If the return instruction returned a value, replace uses of the call with
// uses of the returned value.
if (!TheCall->use_empty()) {
ReturnInst *R = Returns[0];
if (TheCall == R->getReturnValue())
TheCall->replaceAllUsesWith(UndefValue::get(TheCall->getType()));
else
TheCall->replaceAllUsesWith(R->getReturnValue());
}
// Since we are now done with the Call/Invoke, we can delete it.
TheCall->eraseFromParent();
// Since we are now done with the return instruction, delete it also.
Returns[0]->eraseFromParent();
// We are now done with the inlining.
return true;
}
// Otherwise, we have the normal case, of more than one block to inline or
// multiple return sites.
// We want to clone the entire callee function into the hole between the
// "starter" and "ender" blocks. How we accomplish this depends on whether
// this is an invoke instruction or a call instruction.
BasicBlock *AfterCallBB;
BranchInst *CreatedBranchToNormalDest = nullptr;
if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall)) {
// Add an unconditional branch to make this look like the CallInst case...
CreatedBranchToNormalDest = BranchInst::Create(II->getNormalDest(), TheCall);
// Split the basic block. This guarantees that no PHI nodes will have to be
// updated due to new incoming edges, and make the invoke case more
// symmetric to the call case.
AfterCallBB = OrigBB->splitBasicBlock(CreatedBranchToNormalDest,
CalledFunc->getName()+".exit");
} else { // It's a call
// If this is a call instruction, we need to split the basic block that
// the call lives in.
//
AfterCallBB = OrigBB->splitBasicBlock(TheCall,
CalledFunc->getName()+".exit");
}
// Change the branch that used to go to AfterCallBB to branch to the first
// basic block of the inlined function.
//
TerminatorInst *Br = OrigBB->getTerminator();
assert(Br && Br->getOpcode() == Instruction::Br &&
"splitBasicBlock broken!");
Br->setOperand(0, FirstNewBlock);
// Now that the function is correct, make it a little bit nicer. In
// particular, move the basic blocks inserted from the end of the function
// into the space made by splitting the source basic block.
Caller->getBasicBlockList().splice(AfterCallBB, Caller->getBasicBlockList(),
FirstNewBlock, Caller->end());
// Handle all of the return instructions that we just cloned in, and eliminate
// any users of the original call/invoke instruction.
Type *RTy = CalledFunc->getReturnType();
PHINode *PHI = nullptr;
if (Returns.size() > 1) {
// The PHI node should go at the front of the new basic block to merge all
// possible incoming values.
if (!TheCall->use_empty()) {
PHI = PHINode::Create(RTy, Returns.size(), TheCall->getName(),
AfterCallBB->begin());
// Anything that used the result of the function call should now use the
// PHI node as their operand.
TheCall->replaceAllUsesWith(PHI);
}
// Loop over all of the return instructions adding entries to the PHI node
// as appropriate.
if (PHI) {
for (unsigned i = 0, e = Returns.size(); i != e; ++i) {
ReturnInst *RI = Returns[i];
assert(RI->getReturnValue()->getType() == PHI->getType() &&
"Ret value not consistent in function!");
PHI->addIncoming(RI->getReturnValue(), RI->getParent());
}
}
// Add a branch to the merge points and remove return instructions.
DebugLoc Loc;
for (unsigned i = 0, e = Returns.size(); i != e; ++i) {
ReturnInst *RI = Returns[i];
BranchInst* BI = BranchInst::Create(AfterCallBB, RI);
Loc = RI->getDebugLoc();
BI->setDebugLoc(Loc);
RI->eraseFromParent();
}
// We need to set the debug location to *somewhere* inside the
// inlined function. The line number may be nonsensical, but the
// instruction will at least be associated with the right
// function.
if (CreatedBranchToNormalDest)
CreatedBranchToNormalDest->setDebugLoc(Loc);
} else if (!Returns.empty()) {
// Otherwise, if there is exactly one return value, just replace anything
// using the return value of the call with the computed value.
if (!TheCall->use_empty()) {
if (TheCall == Returns[0]->getReturnValue())
TheCall->replaceAllUsesWith(UndefValue::get(TheCall->getType()));
else
TheCall->replaceAllUsesWith(Returns[0]->getReturnValue());
}
// Update PHI nodes that use the ReturnBB to use the AfterCallBB.
BasicBlock *ReturnBB = Returns[0]->getParent();
ReturnBB->replaceAllUsesWith(AfterCallBB);
// Splice the code from the return block into the block that it will return
// to, which contains the code that was after the call.
AfterCallBB->getInstList().splice(AfterCallBB->begin(),
ReturnBB->getInstList());
if (CreatedBranchToNormalDest)
CreatedBranchToNormalDest->setDebugLoc(Returns[0]->getDebugLoc());
// Delete the return instruction now and empty ReturnBB now.
Returns[0]->eraseFromParent();
ReturnBB->eraseFromParent();
} else if (!TheCall->use_empty()) {
// No returns, but something is using the return value of the call. Just
// nuke the result.
TheCall->replaceAllUsesWith(UndefValue::get(TheCall->getType()));
}
// Since we are now done with the Call/Invoke, we can delete it.
TheCall->eraseFromParent();
// If we inlined any musttail calls and the original return is now
// unreachable, delete it. It can only contain a bitcast and ret.
if (InlinedMustTailCalls && pred_begin(AfterCallBB) == pred_end(AfterCallBB))
AfterCallBB->eraseFromParent();
// We should always be able to fold the entry block of the function into the
// single predecessor of the block...
assert(cast<BranchInst>(Br)->isUnconditional() && "splitBasicBlock broken!");
BasicBlock *CalleeEntry = cast<BranchInst>(Br)->getSuccessor(0);
// Splice the code entry block into calling block, right before the
// unconditional branch.
CalleeEntry->replaceAllUsesWith(OrigBB); // Update PHI nodes
OrigBB->getInstList().splice(Br, CalleeEntry->getInstList());
// Remove the unconditional branch.
OrigBB->getInstList().erase(Br);
// Now we can remove the CalleeEntry block, which is now empty.
Caller->getBasicBlockList().erase(CalleeEntry);
// If we inserted a phi node, check to see if it has a single value (e.g. all
// the entries are the same or undef). If so, remove the PHI so it doesn't
// block other optimizations.
if (PHI) {
auto &DL = Caller->getParent()->getDataLayout();
if (Value *V = SimplifyInstruction(PHI, DL, nullptr, nullptr,
IFI.ACT ? &IFI.ACT->getAssumptionCache(*Caller) : nullptr)) { // HLSL Change: fix nullptr dereference
PHI->replaceAllUsesWith(V);
PHI->eraseFromParent();
}
}
return true;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/PromoteMemoryToRegister.cpp | //===- PromoteMemoryToRegister.cpp - Convert allocas to registers ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file promotes memory references to be register references. It promotes
// alloca instructions which only have loads and stores as uses. An alloca is
// transformed by using iterated dominator frontiers to place PHI nodes, then
// traversing the function in depth-first order to rewrite loads and stores as
// appropriate.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/PromoteMemToReg.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AliasSetTracker.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/IteratedDominanceFrontier.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DIBuilder.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/Module.h"
#include "llvm/Transforms/Utils/Local.h"
#include <algorithm>
using namespace llvm;
#define DEBUG_TYPE "mem2reg"
STATISTIC(NumLocalPromoted, "Number of alloca's promoted within one block");
STATISTIC(NumSingleStore, "Number of alloca's promoted with a single store");
STATISTIC(NumDeadAlloca, "Number of dead alloca's removed");
STATISTIC(NumPHIInsert, "Number of PHI nodes inserted");
bool llvm::isAllocaPromotable(const AllocaInst *AI) {
// FIXME: If the memory unit is of pointer or integer type, we can permit
// assignments to subsections of the memory unit.
unsigned AS = AI->getType()->getAddressSpace();
// Only allow direct and non-volatile loads and stores...
for (const User *U : AI->users()) {
if (const LoadInst *LI = dyn_cast<LoadInst>(U)) {
// Note that atomic loads can be transformed; atomic semantics do
// not have any meaning for a local alloca.
if (LI->isVolatile())
return false;
} else if (const StoreInst *SI = dyn_cast<StoreInst>(U)) {
if (SI->getOperand(0) == AI)
return false; // Don't allow a store OF the AI, only INTO the AI.
// Note that atomic stores can be transformed; atomic semantics do
// not have any meaning for a local alloca.
if (SI->isVolatile())
return false;
} else if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(U)) {
if (II->getIntrinsicID() != Intrinsic::lifetime_start &&
II->getIntrinsicID() != Intrinsic::lifetime_end)
return false;
} else if (const BitCastInst *BCI = dyn_cast<BitCastInst>(U)) {
if (BCI->getType() != Type::getInt8PtrTy(U->getContext(), AS))
return false;
if (!onlyUsedByLifetimeMarkers(BCI))
return false;
} else if (const GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(U)) {
if (GEPI->getType() != Type::getInt8PtrTy(U->getContext(), AS))
return false;
if (!GEPI->hasAllZeroIndices())
return false;
if (!onlyUsedByLifetimeMarkers(GEPI))
return false;
} else {
return false;
}
}
return true;
}
namespace {
struct AllocaInfo {
SmallVector<BasicBlock *, 32> DefiningBlocks;
SmallVector<BasicBlock *, 32> UsingBlocks;
StoreInst *OnlyStore;
BasicBlock *OnlyBlock;
bool OnlyUsedInOneBlock;
Value *AllocaPointerVal;
//DbgDeclareInst *DbgDeclare; // HLSL Change
SmallVector<DbgDeclareInst *, 4> DbgDeclareInsts; // HLSL Change
void clear() {
DefiningBlocks.clear();
UsingBlocks.clear();
OnlyStore = nullptr;
OnlyBlock = nullptr;
OnlyUsedInOneBlock = true;
AllocaPointerVal = nullptr;
// DbgDeclare = nullptr; // HLSL Change
DbgDeclareInsts.clear(); // HLSL Change
}
/// Scan the uses of the specified alloca, filling in the AllocaInfo used
/// by the rest of the pass to reason about the uses of this alloca.
void AnalyzeAlloca(AllocaInst *AI) {
clear();
// As we scan the uses of the alloca instruction, keep track of stores,
// and decide whether all of the loads and stores to the alloca are within
// the same basic block.
for (auto UI = AI->user_begin(), E = AI->user_end(); UI != E;) {
Instruction *User = cast<Instruction>(*UI++);
if (StoreInst *SI = dyn_cast<StoreInst>(User)) {
// Remember the basic blocks which define new values for the alloca
DefiningBlocks.push_back(SI->getParent());
AllocaPointerVal = SI->getOperand(0);
OnlyStore = SI;
} else {
LoadInst *LI = cast<LoadInst>(User);
// Otherwise it must be a load instruction, keep track of variable
// reads.
UsingBlocks.push_back(LI->getParent());
AllocaPointerVal = LI;
}
if (OnlyUsedInOneBlock) {
if (!OnlyBlock)
OnlyBlock = User->getParent();
else if (OnlyBlock != User->getParent())
OnlyUsedInOneBlock = false;
}
}
// DbgDeclare = FindAllocaDbgDeclare(AI); // HLSL Change
FindAllocaDbgDeclare(AI, DbgDeclareInsts); // HLSL Change
}
};
// Data package used by RenamePass()
class RenamePassData {
public:
typedef std::vector<Value *> ValVector;
RenamePassData() : BB(nullptr), Pred(nullptr), Values() {}
RenamePassData(BasicBlock *B, BasicBlock *P, const ValVector &V)
: BB(B), Pred(P), Values(V) {}
BasicBlock *BB;
BasicBlock *Pred;
ValVector Values;
void swap(RenamePassData &RHS) {
std::swap(BB, RHS.BB);
std::swap(Pred, RHS.Pred);
Values.swap(RHS.Values);
}
};
/// \brief This assigns and keeps a per-bb relative ordering of load/store
/// instructions in the block that directly load or store an alloca.
///
/// This functionality is important because it avoids scanning large basic
/// blocks multiple times when promoting many allocas in the same block.
class LargeBlockInfo {
/// \brief For each instruction that we track, keep the index of the
/// instruction.
///
/// The index starts out as the number of the instruction from the start of
/// the block.
DenseMap<const Instruction *, unsigned> InstNumbers;
public:
/// This code only looks at accesses to allocas.
static bool isInterestingInstruction(const Instruction *I) {
return (isa<LoadInst>(I) && isa<AllocaInst>(I->getOperand(0))) ||
(isa<StoreInst>(I) && isa<AllocaInst>(I->getOperand(1)));
}
/// Get or calculate the index of the specified instruction.
unsigned getInstructionIndex(const Instruction *I) {
assert(isInterestingInstruction(I) &&
"Not a load/store to/from an alloca?");
// If we already have this instruction number, return it.
DenseMap<const Instruction *, unsigned>::iterator It = InstNumbers.find(I);
if (It != InstNumbers.end())
return It->second;
// Scan the whole block to get the instruction. This accumulates
// information for every interesting instruction in the block, in order to
// avoid gratuitus rescans.
const BasicBlock *BB = I->getParent();
unsigned InstNo = 0;
for (BasicBlock::const_iterator BBI = BB->begin(), E = BB->end(); BBI != E;
++BBI)
if (isInterestingInstruction(BBI))
InstNumbers[BBI] = InstNo++;
It = InstNumbers.find(I);
assert(It != InstNumbers.end() && "Didn't insert instruction?");
return It->second;
}
void deleteValue(const Instruction *I) { InstNumbers.erase(I); }
void clear() { InstNumbers.clear(); }
};
struct PromoteMem2Reg {
/// The alloca instructions being promoted.
std::vector<AllocaInst *> Allocas;
DominatorTree &DT;
DIBuilder DIB;
/// An AliasSetTracker object to update. If null, don't update it.
AliasSetTracker *AST;
/// A cache of @llvm.assume intrinsics used by SimplifyInstruction.
AssumptionCache *AC;
/// Reverse mapping of Allocas.
DenseMap<AllocaInst *, unsigned> AllocaLookup;
/// \brief The PhiNodes we're adding.
///
/// That map is used to simplify some Phi nodes as we iterate over it, so
/// it should have deterministic iterators. We could use a MapVector, but
/// since we already maintain a map from BasicBlock* to a stable numbering
/// (BBNumbers), the DenseMap is more efficient (also supports removal).
DenseMap<std::pair<unsigned, unsigned>, PHINode *> NewPhiNodes;
/// For each PHI node, keep track of which entry in Allocas it corresponds
/// to.
DenseMap<PHINode *, unsigned> PhiToAllocaMap;
/// If we are updating an AliasSetTracker, then for each alloca that is of
/// pointer type, we keep track of what to copyValue to the inserted PHI
/// nodes here.
std::vector<Value *> PointerAllocaValues;
/// For each alloca, we keep track of the dbg.declare intrinsic that
/// describes it, if any, so that we can convert it to a dbg.value
/// intrinsic if the alloca gets promoted.
// SmallVector<DbgDeclareInst *, 8> AllocaDbgDeclares; // HLSL Change
SmallVector<SmallVector<DbgDeclareInst *, 4>, 8> AllocaDbgDeclares; // HLSL Change
/// The set of basic blocks the renamer has already visited.
///
SmallPtrSet<BasicBlock *, 16> Visited;
/// Contains a stable numbering of basic blocks to avoid non-determinstic
/// behavior.
DenseMap<BasicBlock *, unsigned> BBNumbers;
/// Lazily compute the number of predecessors a block has.
DenseMap<const BasicBlock *, unsigned> BBNumPreds;
public:
PromoteMem2Reg(ArrayRef<AllocaInst *> Allocas, DominatorTree &DT,
AliasSetTracker *AST, AssumptionCache *AC)
: Allocas(Allocas.begin(), Allocas.end()), DT(DT),
DIB(*DT.getRoot()->getParent()->getParent(), /*AllowUnresolved*/ false),
AST(AST), AC(AC) {}
void run();
private:
void RemoveFromAllocasList(unsigned &AllocaIdx) {
Allocas[AllocaIdx] = Allocas.back();
Allocas.pop_back();
--AllocaIdx;
}
unsigned getNumPreds(const BasicBlock *BB) {
unsigned &NP = BBNumPreds[BB];
if (NP == 0)
NP = std::distance(pred_begin(BB), pred_end(BB)) + 1;
return NP - 1;
}
void ComputeLiveInBlocks(AllocaInst *AI, AllocaInfo &Info,
const SmallPtrSetImpl<BasicBlock *> &DefBlocks,
SmallPtrSetImpl<BasicBlock *> &LiveInBlocks,
BasicBlock *LifetimeStartBB);
void RenamePass(BasicBlock *BB, BasicBlock *Pred,
RenamePassData::ValVector &IncVals,
std::vector<RenamePassData> &Worklist);
bool QueuePhiNode(BasicBlock *BB, unsigned AllocaIdx, unsigned &Version);
};
} // end of anonymous namespace
static BasicBlock *determineLifetimeStartBBAndRemoveLifetimeIntrinsicUsers(AllocaInst *AI) {
// Knowing that this alloca is promotable, we know that it's safe to kill all
// instructions except for load and store.
bool DetermineLifetimeStartLoc = true;
BasicBlock *LifetimeStartBB = nullptr;
for (auto UI = AI->user_begin(), UE = AI->user_end(); UI != UE;) {
Instruction *I = cast<Instruction>(*UI);
++UI;
if (isa<LoadInst>(I) || isa<StoreInst>(I))
continue;
if (!I->getType()->isVoidTy()) {
// The only users of this bitcast/GEP instruction are lifetime intrinsics.
for (auto UUI = I->user_begin(), UUE = I->user_end(); UUI != UUE;) {
IntrinsicInst *Inst = dyn_cast<IntrinsicInst>(*UUI);
assert(Inst);
++UUI;
if (DetermineLifetimeStartLoc && Inst->getIntrinsicID() == Intrinsic::lifetime_start) {
if (!LifetimeStartBB) {
// Remember the lifetime start block.
LifetimeStartBB = Inst->getParent();
} else {
// We currently don't handle alloca with multiple lifetime.start
// intrinsics because there can be lots of complicated cases such
// as multiple disjoint lifetimes in a single block.
// Clear the block and stop looking for a new one.
LifetimeStartBB = nullptr;
DetermineLifetimeStartLoc = false;
}
}
Inst->eraseFromParent();
}
}
I->eraseFromParent();
}
return LifetimeStartBB;
}
/// \brief Rewrite as many loads as possible given a single store.
///
/// When there is only a single store, we can use the domtree to trivially
/// replace all of the dominated loads with the stored value. Do so, and return
/// true if this has successfully promoted the alloca entirely. If this returns
/// false there were some loads which were not dominated by the single store
/// and thus must be phi-ed with undef. We fall back to the standard alloca
/// promotion algorithm in that case.
static bool rewriteSingleStoreAlloca(AllocaInst *AI, AllocaInfo &Info,
LargeBlockInfo &LBI,
DominatorTree &DT,
AliasSetTracker *AST) {
StoreInst *OnlyStore = Info.OnlyStore;
bool StoringGlobalVal = !isa<Instruction>(OnlyStore->getOperand(0));
BasicBlock *StoreBB = OnlyStore->getParent();
int StoreIndex = -1;
// Clear out UsingBlocks. We will reconstruct it here if needed.
Info.UsingBlocks.clear();
for (auto UI = AI->user_begin(), E = AI->user_end(); UI != E;) {
Instruction *UserInst = cast<Instruction>(*UI++);
if (!isa<LoadInst>(UserInst)) {
assert(UserInst == OnlyStore && "Should only have load/stores");
continue;
}
LoadInst *LI = cast<LoadInst>(UserInst);
// Okay, if we have a load from the alloca, we want to replace it with the
// only value stored to the alloca. We can do this if the value is
// dominated by the store. If not, we use the rest of the mem2reg machinery
// to insert the phi nodes as needed.
if (!StoringGlobalVal) { // Non-instructions are always dominated.
if (LI->getParent() == StoreBB) {
// If we have a use that is in the same block as the store, compare the
// indices of the two instructions to see which one came first. If the
// load came before the store, we can't handle it.
if (StoreIndex == -1)
StoreIndex = LBI.getInstructionIndex(OnlyStore);
if (unsigned(StoreIndex) > LBI.getInstructionIndex(LI)) {
// Can't handle this load, bail out.
Info.UsingBlocks.push_back(StoreBB);
continue;
}
} else if (LI->getParent() != StoreBB &&
!DT.dominates(StoreBB, LI->getParent())) {
// If the load and store are in different blocks, use BB dominance to
// check their relationships. If the store doesn't dom the use, bail
// out.
Info.UsingBlocks.push_back(LI->getParent());
continue;
}
}
// Otherwise, we *can* safely rewrite this load.
Value *ReplVal = OnlyStore->getOperand(0);
// If the replacement value is the load, this must occur in unreachable
// code.
if (ReplVal == LI)
ReplVal = UndefValue::get(LI->getType());
LI->replaceAllUsesWith(ReplVal);
if (AST && LI->getType()->isPointerTy())
AST->deleteValue(LI);
LI->eraseFromParent();
LBI.deleteValue(LI);
}
// Finally, after the scan, check to see if the store is all that is left.
if (!Info.UsingBlocks.empty())
return false; // If not, we'll have to fall back for the remainder.
// Record debuginfo for the store and remove the declaration's
// debuginfo.
// if (DbgDeclareInst *DDI = Info.DbgDeclare) { // HLSL Change
for (DbgDeclareInst *DDI : Info.DbgDeclareInsts) {
DIBuilder DIB(*AI->getParent()->getParent()->getParent(),
/*AllowUnresolved*/ false);
ConvertDebugDeclareToDebugValue(DDI, Info.OnlyStore, DIB);
DDI->eraseFromParent();
LBI.deleteValue(DDI);
}
// Remove the (now dead) store and alloca.
Info.OnlyStore->eraseFromParent();
LBI.deleteValue(Info.OnlyStore);
if (AST)
AST->deleteValue(AI);
AI->eraseFromParent();
LBI.deleteValue(AI);
return true;
}
/// Many allocas are only used within a single basic block. If this is the
/// case, avoid traversing the CFG and inserting a lot of potentially useless
/// PHI nodes by just performing a single linear pass over the basic block
/// using the Alloca.
///
/// If we cannot promote this alloca (because it is read before it is written),
/// return false. This is necessary in cases where, due to control flow, the
/// alloca is undefined only on some control flow paths. e.g. code like
/// this is correct in LLVM IR:
/// // A is an alloca with no stores so far
/// for (...) {
/// int t = *A;
/// if (!first_iteration)
/// use(t);
/// *A = 42;
/// }
static bool promoteSingleBlockAlloca(AllocaInst *AI, const AllocaInfo &Info,
LargeBlockInfo &LBI,
AliasSetTracker *AST) {
// The trickiest case to handle is when we have large blocks. Because of this,
// this code is optimized assuming that large blocks happen. This does not
// significantly pessimize the small block case. This uses LargeBlockInfo to
// make it efficient to get the index of various operations in the block.
// Walk the use-def list of the alloca, getting the locations of all stores.
typedef SmallVector<std::pair<unsigned, StoreInst *>, 64> StoresByIndexTy;
StoresByIndexTy StoresByIndex;
for (User *U : AI->users())
if (StoreInst *SI = dyn_cast<StoreInst>(U))
StoresByIndex.push_back(std::make_pair(LBI.getInstructionIndex(SI), SI));
// Sort the stores by their index, making it efficient to do a lookup with a
// binary search.
std::sort(StoresByIndex.begin(), StoresByIndex.end(), less_first());
// Walk all of the loads from this alloca, replacing them with the nearest
// store above them, if any.
for (auto UI = AI->user_begin(), E = AI->user_end(); UI != E;) {
LoadInst *LI = dyn_cast<LoadInst>(*UI++);
if (!LI)
continue;
unsigned LoadIdx = LBI.getInstructionIndex(LI);
// Find the nearest store that has a lower index than this load.
StoresByIndexTy::iterator I =
std::lower_bound(StoresByIndex.begin(), StoresByIndex.end(),
std::make_pair(LoadIdx,
static_cast<StoreInst *>(nullptr)),
less_first());
if (I == StoresByIndex.begin()) {
if (StoresByIndex.empty())
// If there are no stores, the load takes the undef value.
LI->replaceAllUsesWith(UndefValue::get(LI->getType()));
else
// There is no store before this load, bail out (load may be affected
// by the following stores - see main comment).
return false;
}
else {
// Otherwise, there was a store before this load, the load takes its value.
LI->replaceAllUsesWith(std::prev(I)->second->getOperand(0));
}
if (AST && LI->getType()->isPointerTy())
AST->deleteValue(LI);
LI->eraseFromParent();
LBI.deleteValue(LI);
}
// Remove the (now dead) stores and alloca.
while (!AI->use_empty()) {
StoreInst *SI = cast<StoreInst>(AI->user_back());
// Record debuginfo for the store before removing it.
// if (DbgDeclareInst *DDI = Info.DbgDeclare) { // HLSL Change
for (DbgDeclareInst *DDI : Info.DbgDeclareInsts) { // HLSL Change
DIBuilder DIB(*AI->getParent()->getParent()->getParent(),
/*AllowUnresolved*/ false);
ConvertDebugDeclareToDebugValue(DDI, SI, DIB);
}
SI->eraseFromParent();
LBI.deleteValue(SI);
}
if (AST)
AST->deleteValue(AI);
AI->eraseFromParent();
LBI.deleteValue(AI);
// The alloca's debuginfo can be removed as well.
// if (DbgDeclareInst *DDI = Info.DbgDeclare) { // HLSL Change
for (DbgDeclareInst *DDI : Info.DbgDeclareInsts) { // HLSL Change
DDI->eraseFromParent();
LBI.deleteValue(DDI);
}
++NumLocalPromoted;
return true;
}
void PromoteMem2Reg::run() {
Function &F = *DT.getRoot()->getParent();
if (AST)
PointerAllocaValues.resize(Allocas.size());
AllocaDbgDeclares.resize(Allocas.size());
AllocaInfo Info;
LargeBlockInfo LBI;
IDFCalculator IDF(DT);
for (unsigned AllocaNum = 0; AllocaNum != Allocas.size(); ++AllocaNum) {
AllocaInst *AI = Allocas[AllocaNum];
assert(isAllocaPromotable(AI) && "Cannot promote non-promotable alloca!");
assert(AI->getParent()->getParent() == &F &&
"All allocas should be in the same function, which is same as DF!");
BasicBlock *LifetimeStartBB = determineLifetimeStartBBAndRemoveLifetimeIntrinsicUsers(AI);
if (AI->use_empty()) {
// If there are no uses of the alloca, just delete it now.
if (AST)
AST->deleteValue(AI);
AI->eraseFromParent();
// Remove the alloca from the Allocas list, since it has been processed
RemoveFromAllocasList(AllocaNum);
++NumDeadAlloca;
continue;
}
// Calculate the set of read and write-locations for each alloca. This is
// analogous to finding the 'uses' and 'definitions' of each variable.
Info.AnalyzeAlloca(AI);
// Determine whether this alloca only has one store *before* potentially
// adding a lifetime.start block as another definition. This allows to
// rewrite such an alloca efficiently if possible but still benefit from
// correct lifetime information should the single store not dominate all
// loads.
const bool IsSingleStoreAlloca = Info.DefiningBlocks.size() == 1;
// If there is only a single store to this value, replace any loads of
// it that are directly dominated by the definition with the value stored.
if (IsSingleStoreAlloca) {
if (rewriteSingleStoreAlloca(AI, Info, LBI, DT, AST)) {
// The alloca has been processed, move on.
RemoveFromAllocasList(AllocaNum);
++NumSingleStore;
continue;
}
}
// If the alloca is only read and written in one basic block, just perform a
// linear sweep over the block to eliminate it.
if (Info.OnlyUsedInOneBlock &&
promoteSingleBlockAlloca(AI, Info, LBI, AST)) {
// The alloca has been processed, move on.
RemoveFromAllocasList(AllocaNum);
continue;
}
// If we haven't computed a numbering for the BB's in the function, do so
// now.
if (BBNumbers.empty()) {
unsigned ID = 0;
for (auto &BB : F)
BBNumbers[&BB] = ID++;
}
// If we have an AST to keep updated, remember some pointer value that is
// stored into the alloca.
if (AST)
PointerAllocaValues[AllocaNum] = Info.AllocaPointerVal;
// Remember the dbg.declare intrinsic describing this alloca, if any.
// if (Info.DbgDeclare)
if (Info.DbgDeclareInsts.size())
AllocaDbgDeclares[AllocaNum] = Info.DbgDeclareInsts;
// Keep the reverse mapping of the 'Allocas' array for the rename pass.
AllocaLookup[Allocas[AllocaNum]] = AllocaNum;
// At this point, we're committed to promoting the alloca using IDF's, and
// the standard SSA construction algorithm. Determine which blocks need PHI
// nodes and see if we can optimize out some work by avoiding insertion of
// dead phi nodes.
// Unique the set of defining blocks for efficient lookup.
SmallPtrSet<BasicBlock *, 32> DefBlocks;
DefBlocks.insert(Info.DefiningBlocks.begin(), Info.DefiningBlocks.end());
// Determine which blocks the value is live in. These are blocks which lead
// to uses.
SmallPtrSet<BasicBlock *, 32> LiveInBlocks;
ComputeLiveInBlocks(AI, Info, DefBlocks, LiveInBlocks, LifetimeStartBB);
// If there is a lifetime start block, add it to the def blocks now.
// This ensures that the block that holds the lifetime.start call is treated
// as a "definition" by IDF to prevent phi nodes inserted into loop headers
// due to false dependencies.
if (LifetimeStartBB) {
DefBlocks.insert(LifetimeStartBB);
}
// At this point, we're committed to promoting the alloca using IDF's, and
// the standard SSA construction algorithm. Determine which blocks need phi
// nodes and see if we can optimize out some work by avoiding insertion of
// dead phi nodes.
IDF.setLiveInBlocks(LiveInBlocks);
IDF.setDefiningBlocks(DefBlocks);
SmallVector<BasicBlock *, 32> PHIBlocks;
IDF.calculate(PHIBlocks);
if (PHIBlocks.size() > 1)
std::sort(PHIBlocks.begin(), PHIBlocks.end(),
[this](BasicBlock *A, BasicBlock *B) {
return BBNumbers.lookup(A) < BBNumbers.lookup(B);
});
unsigned CurrentVersion = 0;
for (unsigned i = 0, e = PHIBlocks.size(); i != e; ++i)
QueuePhiNode(PHIBlocks[i], AllocaNum, CurrentVersion);
}
if (Allocas.empty())
return; // All of the allocas must have been trivial!
LBI.clear();
// Set the incoming values for the basic block to be null values for all of
// the alloca's. We do this in case there is a load of a value that has not
// been stored yet. In this case, it will get this null value.
//
RenamePassData::ValVector Values(Allocas.size());
for (unsigned i = 0, e = Allocas.size(); i != e; ++i)
Values[i] = UndefValue::get(Allocas[i]->getAllocatedType());
// Walks all basic blocks in the function performing the SSA rename algorithm
// and inserting the phi nodes we marked as necessary
//
std::vector<RenamePassData> RenamePassWorkList;
RenamePassWorkList.emplace_back(F.begin(), nullptr, std::move(Values));
do {
RenamePassData RPD;
RPD.swap(RenamePassWorkList.back());
RenamePassWorkList.pop_back();
// RenamePass may add new worklist entries.
RenamePass(RPD.BB, RPD.Pred, RPD.Values, RenamePassWorkList);
} while (!RenamePassWorkList.empty());
// The renamer uses the Visited set to avoid infinite loops. Clear it now.
Visited.clear();
// Remove the allocas themselves from the function.
for (unsigned i = 0, e = Allocas.size(); i != e; ++i) {
Instruction *A = Allocas[i];
// If there are any uses of the alloca instructions left, they must be in
// unreachable basic blocks that were not processed by walking the dominator
// tree. Just delete the users now.
if (!A->use_empty())
A->replaceAllUsesWith(UndefValue::get(A->getType()));
if (AST)
AST->deleteValue(A);
A->eraseFromParent();
}
const DataLayout &DL = F.getParent()->getDataLayout();
#if 0 // HLSL Change // Do not remove dbg.declares here.
// Remove alloca's dbg.declare instrinsics from the function.
for (unsigned i = 0, e = AllocaDbgDeclares.size(); i != e; ++i)
if (DbgDeclareInst *DDI = AllocaDbgDeclares[i])
DDI->eraseFromParent();
#endif // HLSL Change
// Loop over all of the PHI nodes and see if there are any that we can get
// rid of because they merge all of the same incoming values. This can
// happen due to undef values coming into the PHI nodes. This process is
// iterative, because eliminating one PHI node can cause others to be removed.
bool EliminatedAPHI = true;
while (EliminatedAPHI) {
EliminatedAPHI = false;
// Iterating over NewPhiNodes is deterministic, so it is safe to try to
// simplify and RAUW them as we go. If it was not, we could add uses to
// the values we replace with in a non-deterministic order, thus creating
// non-deterministic def->use chains.
for (DenseMap<std::pair<unsigned, unsigned>, PHINode *>::iterator
I = NewPhiNodes.begin(),
E = NewPhiNodes.end();
I != E;) {
PHINode *PN = I->second;
// If this PHI node merges one value and/or undefs, get the value.
if (Value *V = SimplifyInstruction(PN, DL, nullptr, &DT, AC)) {
if (AST && PN->getType()->isPointerTy())
AST->deleteValue(PN);
PN->replaceAllUsesWith(V);
PN->eraseFromParent();
NewPhiNodes.erase(I++);
EliminatedAPHI = true;
continue;
}
++I;
}
}
// At this point, the renamer has added entries to PHI nodes for all reachable
// code. Unfortunately, there may be unreachable blocks which the renamer
// hasn't traversed. If this is the case, the PHI nodes may not
// have incoming values for all predecessors. Loop over all PHI nodes we have
// created, inserting undef values if they are missing any incoming values.
//
for (DenseMap<std::pair<unsigned, unsigned>, PHINode *>::iterator
I = NewPhiNodes.begin(),
E = NewPhiNodes.end();
I != E; ++I) {
// We want to do this once per basic block. As such, only process a block
// when we find the PHI that is the first entry in the block.
PHINode *SomePHI = I->second;
BasicBlock *BB = SomePHI->getParent();
if (&BB->front() != SomePHI)
continue;
// Only do work here if there the PHI nodes are missing incoming values. We
// know that all PHI nodes that were inserted in a block will have the same
// number of incoming values, so we can just check any of them.
if (SomePHI->getNumIncomingValues() == getNumPreds(BB))
continue;
// Get the preds for BB.
SmallVector<BasicBlock *, 16> Preds(pred_begin(BB), pred_end(BB));
// Ok, now we know that all of the PHI nodes are missing entries for some
// basic blocks. Start by sorting the incoming predecessors for efficient
// access.
std::sort(Preds.begin(), Preds.end());
// Now we loop through all BB's which have entries in SomePHI and remove
// them from the Preds list.
for (unsigned i = 0, e = SomePHI->getNumIncomingValues(); i != e; ++i) {
// Do a log(n) search of the Preds list for the entry we want.
SmallVectorImpl<BasicBlock *>::iterator EntIt = std::lower_bound(
Preds.begin(), Preds.end(), SomePHI->getIncomingBlock(i));
assert(EntIt != Preds.end() && *EntIt == SomePHI->getIncomingBlock(i) &&
"PHI node has entry for a block which is not a predecessor!");
// Remove the entry
Preds.erase(EntIt);
}
// At this point, the blocks left in the preds list must have dummy
// entries inserted into every PHI nodes for the block. Update all the phi
// nodes in this block that we are inserting (there could be phis before
// mem2reg runs).
unsigned NumBadPreds = SomePHI->getNumIncomingValues();
BasicBlock::iterator BBI = BB->begin();
while ((SomePHI = dyn_cast<PHINode>(BBI++)) &&
SomePHI->getNumIncomingValues() == NumBadPreds) {
Value *UndefVal = UndefValue::get(SomePHI->getType());
for (unsigned pred = 0, e = Preds.size(); pred != e; ++pred)
SomePHI->addIncoming(UndefVal, Preds[pred]);
}
}
// HLSL Change - Begin
// Create dbg.value instructions for all generated PHI nodes.
for (DenseMap<std::pair<unsigned, unsigned>, PHINode *>::iterator
I = NewPhiNodes.begin(),
E = NewPhiNodes.end();
I != E; ++I) {
PHINode *PN = I->second;
unsigned AllocaNum = I->first.second;
ArrayRef<DbgDeclareInst *> DDIs = AllocaDbgDeclares[AllocaNum];
for (DbgDeclareInst *DDI : DDIs) {
DIBuilder DIB(*PN->getModule());
DIB.insertDbgValueIntrinsic(PN, 0, DDI->getVariable(), DDI->getExpression(), DDI->getDebugLoc(), PN->getParent()->getFirstNonPHI());
}
}
// Remove alloca's dbg.declare instrinsics from the function.
for (unsigned i = 0, e = AllocaDbgDeclares.size(); i != e; ++i)
for (DbgDeclareInst *DDI : AllocaDbgDeclares[i])
DDI->eraseFromParent();
// HLSL Change - End
NewPhiNodes.clear();
}
/// \brief Determine which blocks the value is live in.
///
/// These are blocks which lead to uses. Knowing this allows us to avoid
/// inserting PHI nodes into blocks which don't lead to uses (thus, the
/// inserted phi nodes would be dead).
///
/// The lifetime start block is important for cases where lifetime is restricted
/// to a loop and not all loads are dominated by stores. When walking up the
/// CFG, stopping at this block prevents the value from being considered live in
/// the loop header, which in turn prevents the value from being live across
/// multiple loop iterations through a phi with undef as input from the preheader.
/// Also, the block must not even be considered as starting point for the CFG
/// traversal since the value can't be live-in before its lifetime starts.
void PromoteMem2Reg::ComputeLiveInBlocks(
AllocaInst *AI, AllocaInfo &Info,
const SmallPtrSetImpl<BasicBlock *> &DefBlocks,
SmallPtrSetImpl<BasicBlock *> &LiveInBlocks,
BasicBlock *LifetimeStartBB) {
// To determine liveness, we must iterate through the predecessors of blocks
// where the def is live. Blocks are added to the worklist if we need to
// check their predecessors. Start with all the using blocks.
SmallVector<BasicBlock *, 64> LiveInBlockWorklist(Info.UsingBlocks.begin(),
Info.UsingBlocks.end());
// If any of the using blocks is also a definition block, check to see if the
// definition occurs before or after the use. If it happens before the use,
// the value isn't really live-in.
for (unsigned i = 0, e = LiveInBlockWorklist.size(); i != e; ++i) {
BasicBlock *BB = LiveInBlockWorklist[i];
if (!DefBlocks.count(BB))
continue;
// If lifetime of this value starts in this block it isn't live-in.
// Even if the block is in a loop, a load before the lifetime intrinsic is
// dead by definition since lifetime must also end in the same loop
// iteration. In fact, this very condition prevents false dependencies
// across loop iterations that in turn cause phi nodes.
if (BB == LifetimeStartBB) {
LiveInBlockWorklist[i] = LiveInBlockWorklist.back();
LiveInBlockWorklist.pop_back();
--i, --e;
continue;
}
// Okay, this is a block that both uses and defines the value. If the first
// reference to the alloca is a def (store), then we know it isn't live-in.
for (BasicBlock::iterator I = BB->begin();; ++I) {
if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
if (SI->getOperand(1) != AI)
continue;
// We found a store to the alloca before a load. The alloca is not
// actually live-in here.
LiveInBlockWorklist[i] = LiveInBlockWorklist.back();
LiveInBlockWorklist.pop_back();
--i, --e;
break;
}
if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
if (LI->getOperand(0) != AI)
continue;
// Okay, we found a load before a store to the alloca. It is actually
// live into this block.
break;
}
}
}
// Now that we have a set of blocks where the phi is live-in, recursively add
// their predecessors until we find the full region the value is live.
while (!LiveInBlockWorklist.empty()) {
BasicBlock *BB = LiveInBlockWorklist.pop_back_val();
// The block really is live in here, insert it into the set. If already in
// the set, then it has already been processed.
if (!LiveInBlocks.insert(BB).second)
continue;
// Since the value is live into BB, it is either defined in a predecessor or
// live into it to. Add the preds to the worklist unless they are a
// defining block.
for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) {
BasicBlock *P = *PI;
// The value is not live into a predecessor if it defines the value.
if (DefBlocks.count(P))
continue;
// The value is not live into a predecessor if lifetime starts there.
if (P == LifetimeStartBB)
continue;
// Otherwise it is, add to the worklist.
LiveInBlockWorklist.push_back(P);
}
}
}
/// \brief Queue a phi-node to be added to a basic-block for a specific Alloca.
///
/// Returns true if there wasn't already a phi-node for that variable
bool PromoteMem2Reg::QueuePhiNode(BasicBlock *BB, unsigned AllocaNo,
unsigned &Version) {
// Look up the basic-block in question.
PHINode *&PN = NewPhiNodes[std::make_pair(BBNumbers[BB], AllocaNo)];
// If the BB already has a phi node added for the i'th alloca then we're done!
if (PN)
return false;
// Create a PhiNode using the dereferenced type... and add the phi-node to the
// BasicBlock.
PN = PHINode::Create(Allocas[AllocaNo]->getAllocatedType(), getNumPreds(BB),
Allocas[AllocaNo]->getName() + "." + Twine(Version++),
BB->begin());
++NumPHIInsert;
PhiToAllocaMap[PN] = AllocaNo;
if (AST && PN->getType()->isPointerTy())
AST->copyValue(PointerAllocaValues[AllocaNo], PN);
return true;
}
/// \brief Recursively traverse the CFG of the function, renaming loads and
/// stores to the allocas which we are promoting.
///
/// IncomingVals indicates what value each Alloca contains on exit from the
/// predecessor block Pred.
void PromoteMem2Reg::RenamePass(BasicBlock *BB, BasicBlock *Pred,
RenamePassData::ValVector &IncomingVals,
std::vector<RenamePassData> &Worklist) {
NextIteration:
// If we are inserting any phi nodes into this BB, they will already be in the
// block.
if (PHINode *APN = dyn_cast<PHINode>(BB->begin())) {
// If we have PHI nodes to update, compute the number of edges from Pred to
// BB.
if (PhiToAllocaMap.count(APN)) {
// We want to be able to distinguish between PHI nodes being inserted by
// this invocation of mem2reg from those phi nodes that already existed in
// the IR before mem2reg was run. We determine that APN is being inserted
// because it is missing incoming edges. All other PHI nodes being
// inserted by this pass of mem2reg will have the same number of incoming
// operands so far. Remember this count.
unsigned NewPHINumOperands = APN->getNumOperands();
unsigned NumEdges = std::count(succ_begin(Pred), succ_end(Pred), BB);
assert(NumEdges && "Must be at least one edge from Pred to BB!");
// Add entries for all the phis.
BasicBlock::iterator PNI = BB->begin();
do {
unsigned AllocaNo = PhiToAllocaMap[APN];
// Add N incoming values to the PHI node.
for (unsigned i = 0; i != NumEdges; ++i)
APN->addIncoming(IncomingVals[AllocaNo], Pred);
// The currently active variable for this block is now the PHI.
IncomingVals[AllocaNo] = APN;
// Get the next phi node.
++PNI;
APN = dyn_cast<PHINode>(PNI);
if (!APN)
break;
// Verify that it is missing entries. If not, it is not being inserted
// by this mem2reg invocation so we want to ignore it.
} while (APN->getNumOperands() == NewPHINumOperands);
}
}
// Don't revisit blocks.
if (!Visited.insert(BB).second)
return;
for (BasicBlock::iterator II = BB->begin(); !isa<TerminatorInst>(II);) {
Instruction *I = II++; // get the instruction, increment iterator
if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
AllocaInst *Src = dyn_cast<AllocaInst>(LI->getPointerOperand());
if (!Src)
continue;
DenseMap<AllocaInst *, unsigned>::iterator AI = AllocaLookup.find(Src);
if (AI == AllocaLookup.end())
continue;
Value *V = IncomingVals[AI->second];
// Anything using the load now uses the current value.
LI->replaceAllUsesWith(V);
if (AST && LI->getType()->isPointerTy())
AST->deleteValue(LI);
BB->getInstList().erase(LI);
} else if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
// Delete this instruction and mark the name as the current holder of the
// value
AllocaInst *Dest = dyn_cast<AllocaInst>(SI->getPointerOperand());
if (!Dest)
continue;
DenseMap<AllocaInst *, unsigned>::iterator ai = AllocaLookup.find(Dest);
if (ai == AllocaLookup.end())
continue;
// what value were we writing?
IncomingVals[ai->second] = SI->getOperand(0);
// Record debuginfo for the store before removing it.
// if (DbgDeclareInst *DDI = AllocaDbgDeclares[ai->second]) // HLSL Change
for (DbgDeclareInst *DDI : AllocaDbgDeclares[ai->second]) // HLSL Change
ConvertDebugDeclareToDebugValue(DDI, SI, DIB);
BB->getInstList().erase(SI);
}
}
// 'Recurse' to our successors.
succ_iterator I = succ_begin(BB), E = succ_end(BB);
if (I == E)
return;
// Keep track of the successors so we don't visit the same successor twice
SmallPtrSet<BasicBlock *, 8> VisitedSuccs;
// Handle the first successor without using the worklist.
VisitedSuccs.insert(*I);
Pred = BB;
BB = *I;
++I;
for (; I != E; ++I)
if (VisitedSuccs.insert(*I).second)
Worklist.emplace_back(*I, Pred, IncomingVals);
goto NextIteration;
}
void llvm::PromoteMemToReg(ArrayRef<AllocaInst *> Allocas, DominatorTree &DT,
AliasSetTracker *AST, AssumptionCache *AC) {
// If there is nothing to do, bail out...
if (Allocas.empty())
return;
PromoteMem2Reg(Allocas, DT, AST, AC).run();
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/InstructionNamer.cpp | //===- InstructionNamer.cpp - Give anonymous instructions names -----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This is a little utility pass that gives instructions names, this is mostly
// useful when diffing the effect of an optimization because deleting an
// unnamed instruction can change all other instruction numbering, making the
// diff very noisy.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Scalar.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Type.h"
#include "llvm/Pass.h"
using namespace llvm;
namespace {
struct InstNamer : public FunctionPass {
static char ID; // Pass identification, replacement for typeid
InstNamer() : FunctionPass(ID) {
initializeInstNamerPass(*PassRegistry::getPassRegistry());
}
void getAnalysisUsage(AnalysisUsage &Info) const override {
Info.setPreservesAll();
}
bool runOnFunction(Function &F) override {
for (Function::arg_iterator AI = F.arg_begin(), AE = F.arg_end();
AI != AE; ++AI)
if (!AI->hasName() && !AI->getType()->isVoidTy())
AI->setName("arg");
for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) {
if (!BB->hasName())
BB->setName("bb");
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
if (!I->hasName() && !I->getType()->isVoidTy())
I->setName("tmp");
}
return true;
}
};
char InstNamer::ID = 0;
}
INITIALIZE_PASS(InstNamer, "instnamer",
"Assign names to anonymous instructions", false, false)
char &llvm::InstructionNamerID = InstNamer::ID;
//===----------------------------------------------------------------------===//
//
// InstructionNamer - Give any unnamed non-void instructions "tmp" names.
//
FunctionPass *llvm::createInstructionNamerPass() {
return new InstNamer();
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/CmpInstAnalysis.cpp | //===- CmpInstAnalysis.cpp - Utils to help fold compares ---------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file holds routines to help analyse compare instructions
// and fold them into constants or other compare instructions
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/CmpInstAnalysis.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Instructions.h"
using namespace llvm;
/// getICmpCode - Encode a icmp predicate into a three bit mask. These bits
/// are carefully arranged to allow folding of expressions such as:
///
/// (A < B) | (A > B) --> (A != B)
///
/// Note that this is only valid if the first and second predicates have the
/// same sign. Is illegal to do: (A u< B) | (A s> B)
///
/// Three bits are used to represent the condition, as follows:
/// 0 A > B
/// 1 A == B
/// 2 A < B
///
/// <=> Value Definition
/// 000 0 Always false
/// 001 1 A > B
/// 010 2 A == B
/// 011 3 A >= B
/// 100 4 A < B
/// 101 5 A != B
/// 110 6 A <= B
/// 111 7 Always true
///
unsigned llvm::getICmpCode(const ICmpInst *ICI, bool InvertPred) {
ICmpInst::Predicate Pred = InvertPred ? ICI->getInversePredicate()
: ICI->getPredicate();
switch (Pred) {
// False -> 0
case ICmpInst::ICMP_UGT: return 1; // 001
case ICmpInst::ICMP_SGT: return 1; // 001
case ICmpInst::ICMP_EQ: return 2; // 010
case ICmpInst::ICMP_UGE: return 3; // 011
case ICmpInst::ICMP_SGE: return 3; // 011
case ICmpInst::ICMP_ULT: return 4; // 100
case ICmpInst::ICMP_SLT: return 4; // 100
case ICmpInst::ICMP_NE: return 5; // 101
case ICmpInst::ICMP_ULE: return 6; // 110
case ICmpInst::ICMP_SLE: return 6; // 110
// True -> 7
default:
llvm_unreachable("Invalid ICmp predicate!");
}
}
/// getICmpValue - This is the complement of getICmpCode, which turns an
/// opcode and two operands into either a constant true or false, or the
/// predicate for a new ICmp instruction. The sign is passed in to determine
/// which kind of predicate to use in the new icmp instruction.
/// Non-NULL return value will be a true or false constant.
/// NULL return means a new ICmp is needed. The predicate for which is
/// output in NewICmpPred.
Value *llvm::getICmpValue(bool Sign, unsigned Code, Value *LHS, Value *RHS,
CmpInst::Predicate &NewICmpPred) {
switch (Code) {
default: llvm_unreachable("Illegal ICmp code!");
case 0: // False.
return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
case 1: NewICmpPred = Sign ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT; break;
case 2: NewICmpPred = ICmpInst::ICMP_EQ; break;
case 3: NewICmpPred = Sign ? ICmpInst::ICMP_SGE : ICmpInst::ICMP_UGE; break;
case 4: NewICmpPred = Sign ? ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT; break;
case 5: NewICmpPred = ICmpInst::ICMP_NE; break;
case 6: NewICmpPred = Sign ? ICmpInst::ICMP_SLE : ICmpInst::ICMP_ULE; break;
case 7: // True.
return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 1);
}
return nullptr;
}
/// PredicatesFoldable - Return true if both predicates match sign or if at
/// least one of them is an equality comparison (which is signless).
bool llvm::PredicatesFoldable(ICmpInst::Predicate p1, ICmpInst::Predicate p2) {
return (CmpInst::isSigned(p1) == CmpInst::isSigned(p2)) ||
(CmpInst::isSigned(p1) && ICmpInst::isEquality(p2)) ||
(CmpInst::isSigned(p2) && ICmpInst::isEquality(p1));
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/UnifyFunctionExitNodes.cpp | //===- UnifyFunctionExitNodes.cpp - Make all functions have a single exit -===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This pass is used to ensure that functions have at most one return
// instruction in them. Additionally, it keeps track of which node is the new
// exit node of the CFG. If there are no exit nodes in the CFG, the getExitNode
// method will return a null pointer.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/UnifyFunctionExitNodes.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Type.h"
#include "llvm/Transforms/Scalar.h"
using namespace llvm;
char UnifyFunctionExitNodes::ID = 0;
INITIALIZE_PASS(UnifyFunctionExitNodes, "mergereturn",
"Unify function exit nodes", false, false)
Pass *llvm::createUnifyFunctionExitNodesPass() {
return new UnifyFunctionExitNodes();
}
void UnifyFunctionExitNodes::getAnalysisUsage(AnalysisUsage &AU) const{
// We preserve the non-critical-edgeness property
AU.addPreservedID(BreakCriticalEdgesID);
// This is a cluster of orthogonal Transforms
AU.addPreservedID(LowerSwitchID);
}
// UnifyAllExitNodes - Unify all exit nodes of the CFG by creating a new
// BasicBlock, and converting all returns to unconditional branches to this
// new basic block. The singular exit node is returned.
//
// If there are no return stmts in the Function, a null pointer is returned.
//
bool UnifyFunctionExitNodes::runOnFunction(Function &F) {
// Loop over all of the blocks in a function, tracking all of the blocks that
// return.
//
std::vector<BasicBlock*> ReturningBlocks;
std::vector<BasicBlock*> UnreachableBlocks;
for(Function::iterator I = F.begin(), E = F.end(); I != E; ++I)
if (isa<ReturnInst>(I->getTerminator()))
ReturningBlocks.push_back(I);
else if (isa<UnreachableInst>(I->getTerminator()))
UnreachableBlocks.push_back(I);
// Then unreachable blocks.
if (UnreachableBlocks.empty()) {
UnreachableBlock = nullptr;
} else if (UnreachableBlocks.size() == 1) {
UnreachableBlock = UnreachableBlocks.front();
} else {
UnreachableBlock = BasicBlock::Create(F.getContext(),
"UnifiedUnreachableBlock", &F);
new UnreachableInst(F.getContext(), UnreachableBlock);
for (std::vector<BasicBlock*>::iterator I = UnreachableBlocks.begin(),
E = UnreachableBlocks.end(); I != E; ++I) {
BasicBlock *BB = *I;
BB->getInstList().pop_back(); // Remove the unreachable inst.
BranchInst::Create(UnreachableBlock, BB);
}
}
// Now handle return blocks.
if (ReturningBlocks.empty()) {
ReturnBlock = nullptr;
return false; // No blocks return
} else if (ReturningBlocks.size() == 1) {
ReturnBlock = ReturningBlocks.front(); // Already has a single return block
return false;
}
// Otherwise, we need to insert a new basic block into the function, add a PHI
// nodes (if the function returns values), and convert all of the return
// instructions into unconditional branches.
//
BasicBlock *NewRetBlock = BasicBlock::Create(F.getContext(),
"UnifiedReturnBlock", &F);
PHINode *PN = nullptr;
if (F.getReturnType()->isVoidTy()) {
ReturnInst::Create(F.getContext(), nullptr, NewRetBlock);
} else {
// If the function doesn't return void... add a PHI node to the block...
PN = PHINode::Create(F.getReturnType(), ReturningBlocks.size(),
"UnifiedRetVal");
NewRetBlock->getInstList().push_back(PN);
ReturnInst::Create(F.getContext(), PN, NewRetBlock);
}
// Loop over all of the blocks, replacing the return instruction with an
// unconditional branch.
//
for (std::vector<BasicBlock*>::iterator I = ReturningBlocks.begin(),
E = ReturningBlocks.end(); I != E; ++I) {
BasicBlock *BB = *I;
// Add an incoming element to the PHI node for every return instruction that
// is merging into this new block...
if (PN)
PN->addIncoming(BB->getTerminator()->getOperand(0), BB);
BB->getInstList().pop_back(); // Remove the return insn
BranchInst::Create(NewRetBlock, BB);
}
ReturnBlock = NewRetBlock;
return true;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/BreakCriticalEdges.cpp | //===- BreakCriticalEdges.cpp - Critical Edge Elimination Pass ------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// BreakCriticalEdges pass - Break all of the critical edges in the CFG by
// inserting a dummy basic block. This pass may be "required" by passes that
// cannot deal with critical edges. For this usage, the structure type is
// forward declared. This pass obviously invalidates the CFG, but can update
// dominator trees.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Scalar.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/CFG.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Type.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
using namespace llvm;
#define DEBUG_TYPE "break-crit-edges"
STATISTIC(NumBroken, "Number of blocks inserted");
namespace {
struct BreakCriticalEdges : public FunctionPass {
static char ID; // Pass identification, replacement for typeid
BreakCriticalEdges() : FunctionPass(ID) {
initializeBreakCriticalEdgesPass(*PassRegistry::getPassRegistry());
}
bool runOnFunction(Function &F) override {
auto *DTWP = getAnalysisIfAvailable<DominatorTreeWrapperPass>();
auto *DT = DTWP ? &DTWP->getDomTree() : nullptr;
auto *LIWP = getAnalysisIfAvailable<LoopInfoWrapperPass>();
auto *LI = LIWP ? &LIWP->getLoopInfo() : nullptr;
unsigned N =
SplitAllCriticalEdges(F, CriticalEdgeSplittingOptions(DT, LI));
NumBroken += N;
return N > 0;
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addPreserved<DominatorTreeWrapperPass>();
AU.addPreserved<LoopInfoWrapperPass>();
// No loop canonicalization guarantees are broken by this pass.
AU.addPreservedID(LoopSimplifyID);
}
};
}
char BreakCriticalEdges::ID = 0;
INITIALIZE_PASS(BreakCriticalEdges, "break-crit-edges",
"Break critical edges in CFG", false, false)
// Publicly exposed interface to pass...
char &llvm::BreakCriticalEdgesID = BreakCriticalEdges::ID;
FunctionPass *llvm::createBreakCriticalEdgesPass() {
return new BreakCriticalEdges();
}
//===----------------------------------------------------------------------===//
// Implementation of the external critical edge manipulation functions
//===----------------------------------------------------------------------===//
/// createPHIsForSplitLoopExit - When a loop exit edge is split, LCSSA form
/// may require new PHIs in the new exit block. This function inserts the
/// new PHIs, as needed. Preds is a list of preds inside the loop, SplitBB
/// is the new loop exit block, and DestBB is the old loop exit, now the
/// successor of SplitBB.
static void createPHIsForSplitLoopExit(ArrayRef<BasicBlock *> Preds,
BasicBlock *SplitBB,
BasicBlock *DestBB) {
// SplitBB shouldn't have anything non-trivial in it yet.
assert((SplitBB->getFirstNonPHI() == SplitBB->getTerminator() ||
SplitBB->isLandingPad()) && "SplitBB has non-PHI nodes!");
// For each PHI in the destination block.
for (BasicBlock::iterator I = DestBB->begin();
PHINode *PN = dyn_cast<PHINode>(I); ++I) {
unsigned Idx = PN->getBasicBlockIndex(SplitBB);
Value *V = PN->getIncomingValue(Idx);
// If the input is a PHI which already satisfies LCSSA, don't create
// a new one.
if (const PHINode *VP = dyn_cast<PHINode>(V))
if (VP->getParent() == SplitBB)
continue;
// Otherwise a new PHI is needed. Create one and populate it.
PHINode *NewPN =
PHINode::Create(PN->getType(), Preds.size(), "split",
SplitBB->isLandingPad() ?
SplitBB->begin() : SplitBB->getTerminator());
for (unsigned i = 0, e = Preds.size(); i != e; ++i)
NewPN->addIncoming(V, Preds[i]);
// Update the original PHI.
PN->setIncomingValue(Idx, NewPN);
}
}
/// SplitCriticalEdge - If this edge is a critical edge, insert a new node to
/// split the critical edge. This will update DominatorTree information if it
/// is available, thus calling this pass will not invalidate either of them.
/// This returns the new block if the edge was split, null otherwise.
///
/// If MergeIdenticalEdges is true (not the default), *all* edges from TI to the
/// specified successor will be merged into the same critical edge block.
/// This is most commonly interesting with switch instructions, which may
/// have many edges to any one destination. This ensures that all edges to that
/// dest go to one block instead of each going to a different block, but isn't
/// the standard definition of a "critical edge".
///
/// It is invalid to call this function on a critical edge that starts at an
/// IndirectBrInst. Splitting these edges will almost always create an invalid
/// program because the address of the new block won't be the one that is jumped
/// to.
///
BasicBlock *llvm::SplitCriticalEdge(TerminatorInst *TI, unsigned SuccNum,
const CriticalEdgeSplittingOptions &Options) {
if (!isCriticalEdge(TI, SuccNum, Options.MergeIdenticalEdges))
return nullptr;
assert(!isa<IndirectBrInst>(TI) &&
"Cannot split critical edge from IndirectBrInst");
BasicBlock *TIBB = TI->getParent();
BasicBlock *DestBB = TI->getSuccessor(SuccNum);
// Splitting the critical edge to a landing pad block is non-trivial. Don't do
// it in this generic function.
if (DestBB->isLandingPad()) return nullptr;
// Create a new basic block, linking it into the CFG.
BasicBlock *NewBB = BasicBlock::Create(TI->getContext(),
TIBB->getName() + "." + DestBB->getName() + "_crit_edge");
// Create our unconditional branch.
BranchInst *NewBI = BranchInst::Create(DestBB, NewBB);
NewBI->setDebugLoc(TI->getDebugLoc());
// Branch to the new block, breaking the edge.
TI->setSuccessor(SuccNum, NewBB);
// Insert the block into the function... right after the block TI lives in.
Function &F = *TIBB->getParent();
Function::iterator FBBI = TIBB;
F.getBasicBlockList().insert(++FBBI, NewBB);
// If there are any PHI nodes in DestBB, we need to update them so that they
// merge incoming values from NewBB instead of from TIBB.
{
unsigned BBIdx = 0;
for (BasicBlock::iterator I = DestBB->begin(); isa<PHINode>(I); ++I) {
// We no longer enter through TIBB, now we come in through NewBB.
// Revector exactly one entry in the PHI node that used to come from
// TIBB to come from NewBB.
PHINode *PN = cast<PHINode>(I);
// Reuse the previous value of BBIdx if it lines up. In cases where we
// have multiple phi nodes with *lots* of predecessors, this is a speed
// win because we don't have to scan the PHI looking for TIBB. This
// happens because the BB list of PHI nodes are usually in the same
// order.
if (PN->getIncomingBlock(BBIdx) != TIBB)
BBIdx = PN->getBasicBlockIndex(TIBB);
PN->setIncomingBlock(BBIdx, NewBB);
}
}
// If there are any other edges from TIBB to DestBB, update those to go
// through the split block, making those edges non-critical as well (and
// reducing the number of phi entries in the DestBB if relevant).
if (Options.MergeIdenticalEdges) {
for (unsigned i = SuccNum+1, e = TI->getNumSuccessors(); i != e; ++i) {
if (TI->getSuccessor(i) != DestBB) continue;
// Remove an entry for TIBB from DestBB phi nodes.
DestBB->removePredecessor(TIBB, Options.DontDeleteUselessPHIs);
// We found another edge to DestBB, go to NewBB instead.
TI->setSuccessor(i, NewBB);
}
}
// If we have nothing to update, just return.
auto *AA = Options.AA;
auto *DT = Options.DT;
auto *LI = Options.LI;
if (!DT && !LI)
return NewBB;
// Now update analysis information. Since the only predecessor of NewBB is
// the TIBB, TIBB clearly dominates NewBB. TIBB usually doesn't dominate
// anything, as there are other successors of DestBB. However, if all other
// predecessors of DestBB are already dominated by DestBB (e.g. DestBB is a
// loop header) then NewBB dominates DestBB.
SmallVector<BasicBlock*, 8> OtherPreds;
// If there is a PHI in the block, loop over predecessors with it, which is
// faster than iterating pred_begin/end.
if (PHINode *PN = dyn_cast<PHINode>(DestBB->begin())) {
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
if (PN->getIncomingBlock(i) != NewBB)
OtherPreds.push_back(PN->getIncomingBlock(i));
} else {
for (pred_iterator I = pred_begin(DestBB), E = pred_end(DestBB);
I != E; ++I) {
BasicBlock *P = *I;
if (P != NewBB)
OtherPreds.push_back(P);
}
}
bool NewBBDominatesDestBB = true;
// Should we update DominatorTree information?
if (DT) {
DomTreeNode *TINode = DT->getNode(TIBB);
// The new block is not the immediate dominator for any other nodes, but
// TINode is the immediate dominator for the new node.
//
if (TINode) { // Don't break unreachable code!
DomTreeNode *NewBBNode = DT->addNewBlock(NewBB, TIBB);
DomTreeNode *DestBBNode = nullptr;
// If NewBBDominatesDestBB hasn't been computed yet, do so with DT.
if (!OtherPreds.empty()) {
DestBBNode = DT->getNode(DestBB);
while (!OtherPreds.empty() && NewBBDominatesDestBB) {
if (DomTreeNode *OPNode = DT->getNode(OtherPreds.back()))
NewBBDominatesDestBB = DT->dominates(DestBBNode, OPNode);
OtherPreds.pop_back();
}
OtherPreds.clear();
}
// If NewBBDominatesDestBB, then NewBB dominates DestBB, otherwise it
// doesn't dominate anything.
if (NewBBDominatesDestBB) {
if (!DestBBNode) DestBBNode = DT->getNode(DestBB);
DT->changeImmediateDominator(DestBBNode, NewBBNode);
}
}
}
// Update LoopInfo if it is around.
if (LI) {
if (Loop *TIL = LI->getLoopFor(TIBB)) {
// If one or the other blocks were not in a loop, the new block is not
// either, and thus LI doesn't need to be updated.
if (Loop *DestLoop = LI->getLoopFor(DestBB)) {
if (TIL == DestLoop) {
// Both in the same loop, the NewBB joins loop.
DestLoop->addBasicBlockToLoop(NewBB, *LI);
} else if (TIL->contains(DestLoop)) {
// Edge from an outer loop to an inner loop. Add to the outer loop.
TIL->addBasicBlockToLoop(NewBB, *LI);
} else if (DestLoop->contains(TIL)) {
// Edge from an inner loop to an outer loop. Add to the outer loop.
DestLoop->addBasicBlockToLoop(NewBB, *LI);
} else {
// Edge from two loops with no containment relation. Because these
// are natural loops, we know that the destination block must be the
// header of its loop (adding a branch into a loop elsewhere would
// create an irreducible loop).
assert(DestLoop->getHeader() == DestBB &&
"Should not create irreducible loops!");
if (Loop *P = DestLoop->getParentLoop())
P->addBasicBlockToLoop(NewBB, *LI);
}
}
// If TIBB is in a loop and DestBB is outside of that loop, we may need
// to update LoopSimplify form and LCSSA form.
if (!TIL->contains(DestBB)) {
assert(!TIL->contains(NewBB) &&
"Split point for loop exit is contained in loop!");
// Update LCSSA form in the newly created exit block.
if (Options.PreserveLCSSA) {
createPHIsForSplitLoopExit(TIBB, NewBB, DestBB);
}
// The only that we can break LoopSimplify form by splitting a critical
// edge is if after the split there exists some edge from TIL to DestBB
// *and* the only edge into DestBB from outside of TIL is that of
// NewBB. If the first isn't true, then LoopSimplify still holds, NewBB
// is the new exit block and it has no non-loop predecessors. If the
// second isn't true, then DestBB was not in LoopSimplify form prior to
// the split as it had a non-loop predecessor. In both of these cases,
// the predecessor must be directly in TIL, not in a subloop, or again
// LoopSimplify doesn't hold.
SmallVector<BasicBlock *, 4> LoopPreds;
for (pred_iterator I = pred_begin(DestBB), E = pred_end(DestBB); I != E;
++I) {
BasicBlock *P = *I;
if (P == NewBB)
continue; // The new block is known.
if (LI->getLoopFor(P) != TIL) {
// No need to re-simplify, it wasn't to start with.
LoopPreds.clear();
break;
}
LoopPreds.push_back(P);
}
if (!LoopPreds.empty()) {
assert(!DestBB->isLandingPad() &&
"We don't split edges to landing pads!");
BasicBlock *NewExitBB = SplitBlockPredecessors(
DestBB, LoopPreds, "split", AA, DT, LI, Options.PreserveLCSSA);
if (Options.PreserveLCSSA)
createPHIsForSplitLoopExit(LoopPreds, NewExitBB, DestBB);
}
}
}
}
return NewBB;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/CloneModule.cpp | //===- CloneModule.cpp - Clone an entire module ---------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the CloneModule interface which makes a copy of an
// entire module.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/Cloning.h"
#include "llvm/IR/Constant.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Module.h"
#include "llvm/Transforms/Utils/ValueMapper.h"
#include "llvm-c/Core.h"
using namespace llvm;
/// CloneModule - Return an exact copy of the specified module. This is not as
/// easy as it might seem because we have to worry about making copies of global
/// variables and functions, and making their (initializers and references,
/// respectively) refer to the right globals.
///
Module *llvm::CloneModule(const Module *M) {
// Create the value map that maps things from the old module over to the new
// module.
ValueToValueMapTy VMap;
return CloneModule(M, VMap);
}
Module *llvm::CloneModule(const Module *M, ValueToValueMapTy &VMap) {
// First off, we need to create the new module.
Module *New = new Module(M->getModuleIdentifier(), M->getContext());
New->setDataLayout(M->getDataLayout());
New->setTargetTriple(M->getTargetTriple());
New->setModuleInlineAsm(M->getModuleInlineAsm());
// Loop over all of the global variables, making corresponding globals in the
// new module. Here we add them to the VMap and to the new Module. We
// don't worry about attributes or initializers, they will come later.
//
for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
I != E; ++I) {
GlobalVariable *GV = new GlobalVariable(*New,
I->getType()->getElementType(),
I->isConstant(), I->getLinkage(),
(Constant*) nullptr, I->getName(),
(GlobalVariable*) nullptr,
I->getThreadLocalMode(),
I->getType()->getAddressSpace());
GV->copyAttributesFrom(I);
VMap[I] = GV;
}
// Loop over the functions in the module, making external functions as before
for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
Function *NF =
Function::Create(cast<FunctionType>(I->getType()->getElementType()),
I->getLinkage(), I->getName(), New);
NF->copyAttributesFrom(I);
VMap[I] = NF;
}
// Loop over the aliases in the module
for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
I != E; ++I) {
auto *PTy = cast<PointerType>(I->getType());
auto *GA = GlobalAlias::create(PTy, I->getLinkage(), I->getName(), New);
GA->copyAttributesFrom(I);
VMap[I] = GA;
}
// Now that all of the things that global variable initializer can refer to
// have been created, loop through and copy the global variable referrers
// over... We also set the attributes on the global now.
//
for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
I != E; ++I) {
GlobalVariable *GV = cast<GlobalVariable>(VMap[I]);
if (I->hasInitializer())
GV->setInitializer(MapValue(I->getInitializer(), VMap));
}
// Similarly, copy over function bodies now...
//
for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
Function *F = cast<Function>(VMap[I]);
if (!I->isDeclaration()) {
Function::arg_iterator DestI = F->arg_begin();
for (Function::const_arg_iterator J = I->arg_begin(); J != I->arg_end();
++J) {
DestI->setName(J->getName());
VMap[J] = DestI++;
}
SmallVector<ReturnInst*, 8> Returns; // Ignore returns cloned.
CloneFunctionInto(F, I, VMap, /*ModuleLevelChanges=*/true, Returns);
}
if (I->hasPersonalityFn())
F->setPersonalityFn(MapValue(I->getPersonalityFn(), VMap));
}
// And aliases
for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
I != E; ++I) {
GlobalAlias *GA = cast<GlobalAlias>(VMap[I]);
if (const Constant *C = I->getAliasee())
GA->setAliasee(MapValue(C, VMap));
}
// And named metadata....
for (Module::const_named_metadata_iterator I = M->named_metadata_begin(),
E = M->named_metadata_end(); I != E; ++I) {
const NamedMDNode &NMD = *I;
NamedMDNode *NewNMD = New->getOrInsertNamedMetadata(NMD.getName());
for (unsigned i = 0, e = NMD.getNumOperands(); i != e; ++i)
NewNMD->addOperand(MapMetadata(NMD.getOperand(i), VMap));
}
return New;
}
// extern "C" { // HLSL Change -Don't use c linkage.
LLVMModuleRef LLVMCloneModule(LLVMModuleRef M) {
return wrap(CloneModule(unwrap(M)));
}
// } // HLSL Change -Don't use c linkage.
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/IntegerDivision.cpp | //===-- IntegerDivision.cpp - Expand integer division ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains an implementation of 32bit and 64bit scalar integer
// division for targets that don't have native support. It's largely derived
// from compiler-rt's implementations of __udivsi3 and __udivmoddi4,
// but hand-tuned for targets that prefer less control flow.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/IntegerDivision.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Intrinsics.h"
#include <utility>
using namespace llvm;
#define DEBUG_TYPE "integer-division"
/// Generate code to compute the remainder of two signed integers. Returns the
/// remainder, which will have the sign of the dividend. Builder's insert point
/// should be pointing where the caller wants code generated, e.g. at the srem
/// instruction. This will generate a urem in the process, and Builder's insert
/// point will be pointing at the uren (if present, i.e. not folded), ready to
/// be expanded if the user wishes
static Value *generateSignedRemainderCode(Value *Dividend, Value *Divisor,
IRBuilder<> &Builder) {
unsigned BitWidth = Dividend->getType()->getIntegerBitWidth();
ConstantInt *Shift;
if (BitWidth == 64) {
Shift = Builder.getInt64(63);
} else {
assert(BitWidth == 32 && "Unexpected bit width");
Shift = Builder.getInt32(31);
}
// Following instructions are generated for both i32 (shift 31) and
// i64 (shift 63).
// ; %dividend_sgn = ashr i32 %dividend, 31
// ; %divisor_sgn = ashr i32 %divisor, 31
// ; %dvd_xor = xor i32 %dividend, %dividend_sgn
// ; %dvs_xor = xor i32 %divisor, %divisor_sgn
// ; %u_dividend = sub i32 %dvd_xor, %dividend_sgn
// ; %u_divisor = sub i32 %dvs_xor, %divisor_sgn
// ; %urem = urem i32 %dividend, %divisor
// ; %xored = xor i32 %urem, %dividend_sgn
// ; %srem = sub i32 %xored, %dividend_sgn
Value *DividendSign = Builder.CreateAShr(Dividend, Shift);
Value *DivisorSign = Builder.CreateAShr(Divisor, Shift);
Value *DvdXor = Builder.CreateXor(Dividend, DividendSign);
Value *DvsXor = Builder.CreateXor(Divisor, DivisorSign);
Value *UDividend = Builder.CreateSub(DvdXor, DividendSign);
Value *UDivisor = Builder.CreateSub(DvsXor, DivisorSign);
Value *URem = Builder.CreateURem(UDividend, UDivisor);
Value *Xored = Builder.CreateXor(URem, DividendSign);
Value *SRem = Builder.CreateSub(Xored, DividendSign);
if (Instruction *URemInst = dyn_cast<Instruction>(URem))
Builder.SetInsertPoint(URemInst);
return SRem;
}
/// Generate code to compute the remainder of two unsigned integers. Returns the
/// remainder. Builder's insert point should be pointing where the caller wants
/// code generated, e.g. at the urem instruction. This will generate a udiv in
/// the process, and Builder's insert point will be pointing at the udiv (if
/// present, i.e. not folded), ready to be expanded if the user wishes
static Value *generatedUnsignedRemainderCode(Value *Dividend, Value *Divisor,
IRBuilder<> &Builder) {
// Remainder = Dividend - Quotient*Divisor
// Following instructions are generated for both i32 and i64
// ; %quotient = udiv i32 %dividend, %divisor
// ; %product = mul i32 %divisor, %quotient
// ; %remainder = sub i32 %dividend, %product
Value *Quotient = Builder.CreateUDiv(Dividend, Divisor);
Value *Product = Builder.CreateMul(Divisor, Quotient);
Value *Remainder = Builder.CreateSub(Dividend, Product);
if (Instruction *UDiv = dyn_cast<Instruction>(Quotient))
Builder.SetInsertPoint(UDiv);
return Remainder;
}
/// Generate code to divide two signed integers. Returns the quotient, rounded
/// towards 0. Builder's insert point should be pointing where the caller wants
/// code generated, e.g. at the sdiv instruction. This will generate a udiv in
/// the process, and Builder's insert point will be pointing at the udiv (if
/// present, i.e. not folded), ready to be expanded if the user wishes.
static Value *generateSignedDivisionCode(Value *Dividend, Value *Divisor,
IRBuilder<> &Builder) {
// Implementation taken from compiler-rt's __divsi3 and __divdi3
unsigned BitWidth = Dividend->getType()->getIntegerBitWidth();
ConstantInt *Shift;
if (BitWidth == 64) {
Shift = Builder.getInt64(63);
} else {
assert(BitWidth == 32 && "Unexpected bit width");
Shift = Builder.getInt32(31);
}
// Following instructions are generated for both i32 (shift 31) and
// i64 (shift 63).
// ; %tmp = ashr i32 %dividend, 31
// ; %tmp1 = ashr i32 %divisor, 31
// ; %tmp2 = xor i32 %tmp, %dividend
// ; %u_dvnd = sub nsw i32 %tmp2, %tmp
// ; %tmp3 = xor i32 %tmp1, %divisor
// ; %u_dvsr = sub nsw i32 %tmp3, %tmp1
// ; %q_sgn = xor i32 %tmp1, %tmp
// ; %q_mag = udiv i32 %u_dvnd, %u_dvsr
// ; %tmp4 = xor i32 %q_mag, %q_sgn
// ; %q = sub i32 %tmp4, %q_sgn
Value *Tmp = Builder.CreateAShr(Dividend, Shift);
Value *Tmp1 = Builder.CreateAShr(Divisor, Shift);
Value *Tmp2 = Builder.CreateXor(Tmp, Dividend);
Value *U_Dvnd = Builder.CreateSub(Tmp2, Tmp);
Value *Tmp3 = Builder.CreateXor(Tmp1, Divisor);
Value *U_Dvsr = Builder.CreateSub(Tmp3, Tmp1);
Value *Q_Sgn = Builder.CreateXor(Tmp1, Tmp);
Value *Q_Mag = Builder.CreateUDiv(U_Dvnd, U_Dvsr);
Value *Tmp4 = Builder.CreateXor(Q_Mag, Q_Sgn);
Value *Q = Builder.CreateSub(Tmp4, Q_Sgn);
if (Instruction *UDiv = dyn_cast<Instruction>(Q_Mag))
Builder.SetInsertPoint(UDiv);
return Q;
}
/// Generates code to divide two unsigned scalar 32-bit or 64-bit integers.
/// Returns the quotient, rounded towards 0. Builder's insert point should
/// point where the caller wants code generated, e.g. at the udiv instruction.
static Value *generateUnsignedDivisionCode(Value *Dividend, Value *Divisor,
IRBuilder<> &Builder) {
// The basic algorithm can be found in the compiler-rt project's
// implementation of __udivsi3.c. Here, we do a lower-level IR based approach
// that's been hand-tuned to lessen the amount of control flow involved.
// Some helper values
IntegerType *DivTy = cast<IntegerType>(Dividend->getType());
unsigned BitWidth = DivTy->getBitWidth();
ConstantInt *Zero;
ConstantInt *One;
ConstantInt *NegOne;
ConstantInt *MSB;
if (BitWidth == 64) {
Zero = Builder.getInt64(0);
One = Builder.getInt64(1);
NegOne = ConstantInt::getSigned(DivTy, -1);
MSB = Builder.getInt64(63);
} else {
assert(BitWidth == 32 && "Unexpected bit width");
Zero = Builder.getInt32(0);
One = Builder.getInt32(1);
NegOne = ConstantInt::getSigned(DivTy, -1);
MSB = Builder.getInt32(31);
}
ConstantInt *True = Builder.getTrue();
BasicBlock *IBB = Builder.GetInsertBlock();
Function *F = IBB->getParent();
Function *CTLZ = Intrinsic::getDeclaration(F->getParent(), Intrinsic::ctlz,
DivTy);
// Our CFG is going to look like:
// +---------------------+
// | special-cases |
// | ... |
// +---------------------+
// | |
// | +----------+
// | | bb1 |
// | | ... |
// | +----------+
// | | |
// | | +------------+
// | | | preheader |
// | | | ... |
// | | +------------+
// | | |
// | | | +---+
// | | | | |
// | | +------------+ |
// | | | do-while | |
// | | | ... | |
// | | +------------+ |
// | | | | |
// | +-----------+ +---+
// | | loop-exit |
// | | ... |
// | +-----------+
// | |
// +-------+
// | ... |
// | end |
// +-------+
BasicBlock *SpecialCases = Builder.GetInsertBlock();
SpecialCases->setName(Twine(SpecialCases->getName(), "_udiv-special-cases"));
BasicBlock *End = SpecialCases->splitBasicBlock(Builder.GetInsertPoint(),
"udiv-end");
BasicBlock *LoopExit = BasicBlock::Create(Builder.getContext(),
"udiv-loop-exit", F, End);
BasicBlock *DoWhile = BasicBlock::Create(Builder.getContext(),
"udiv-do-while", F, End);
BasicBlock *Preheader = BasicBlock::Create(Builder.getContext(),
"udiv-preheader", F, End);
BasicBlock *BB1 = BasicBlock::Create(Builder.getContext(),
"udiv-bb1", F, End);
// We'll be overwriting the terminator to insert our extra blocks
SpecialCases->getTerminator()->eraseFromParent();
// Same instructions are generated for both i32 (msb 31) and i64 (msb 63).
// First off, check for special cases: dividend or divisor is zero, divisor
// is greater than dividend, and divisor is 1.
// ; special-cases:
// ; %ret0_1 = icmp eq i32 %divisor, 0
// ; %ret0_2 = icmp eq i32 %dividend, 0
// ; %ret0_3 = or i1 %ret0_1, %ret0_2
// ; %tmp0 = tail call i32 @llvm.ctlz.i32(i32 %divisor, i1 true)
// ; %tmp1 = tail call i32 @llvm.ctlz.i32(i32 %dividend, i1 true)
// ; %sr = sub nsw i32 %tmp0, %tmp1
// ; %ret0_4 = icmp ugt i32 %sr, 31
// ; %ret0 = or i1 %ret0_3, %ret0_4
// ; %retDividend = icmp eq i32 %sr, 31
// ; %retVal = select i1 %ret0, i32 0, i32 %dividend
// ; %earlyRet = or i1 %ret0, %retDividend
// ; br i1 %earlyRet, label %end, label %bb1
Builder.SetInsertPoint(SpecialCases);
Value *Ret0_1 = Builder.CreateICmpEQ(Divisor, Zero);
Value *Ret0_2 = Builder.CreateICmpEQ(Dividend, Zero);
Value *Ret0_3 = Builder.CreateOr(Ret0_1, Ret0_2);
Value *Tmp0 = Builder.CreateCall(CTLZ, {Divisor, True});
Value *Tmp1 = Builder.CreateCall(CTLZ, {Dividend, True});
Value *SR = Builder.CreateSub(Tmp0, Tmp1);
Value *Ret0_4 = Builder.CreateICmpUGT(SR, MSB);
Value *Ret0 = Builder.CreateOr(Ret0_3, Ret0_4);
Value *RetDividend = Builder.CreateICmpEQ(SR, MSB);
Value *RetVal = Builder.CreateSelect(Ret0, Zero, Dividend);
Value *EarlyRet = Builder.CreateOr(Ret0, RetDividend);
Builder.CreateCondBr(EarlyRet, End, BB1);
// ; bb1: ; preds = %special-cases
// ; %sr_1 = add i32 %sr, 1
// ; %tmp2 = sub i32 31, %sr
// ; %q = shl i32 %dividend, %tmp2
// ; %skipLoop = icmp eq i32 %sr_1, 0
// ; br i1 %skipLoop, label %loop-exit, label %preheader
Builder.SetInsertPoint(BB1);
Value *SR_1 = Builder.CreateAdd(SR, One);
Value *Tmp2 = Builder.CreateSub(MSB, SR);
Value *Q = Builder.CreateShl(Dividend, Tmp2);
Value *SkipLoop = Builder.CreateICmpEQ(SR_1, Zero);
Builder.CreateCondBr(SkipLoop, LoopExit, Preheader);
// ; preheader: ; preds = %bb1
// ; %tmp3 = lshr i32 %dividend, %sr_1
// ; %tmp4 = add i32 %divisor, -1
// ; br label %do-while
Builder.SetInsertPoint(Preheader);
Value *Tmp3 = Builder.CreateLShr(Dividend, SR_1);
Value *Tmp4 = Builder.CreateAdd(Divisor, NegOne);
Builder.CreateBr(DoWhile);
// ; do-while: ; preds = %do-while, %preheader
// ; %carry_1 = phi i32 [ 0, %preheader ], [ %carry, %do-while ]
// ; %sr_3 = phi i32 [ %sr_1, %preheader ], [ %sr_2, %do-while ]
// ; %r_1 = phi i32 [ %tmp3, %preheader ], [ %r, %do-while ]
// ; %q_2 = phi i32 [ %q, %preheader ], [ %q_1, %do-while ]
// ; %tmp5 = shl i32 %r_1, 1
// ; %tmp6 = lshr i32 %q_2, 31
// ; %tmp7 = or i32 %tmp5, %tmp6
// ; %tmp8 = shl i32 %q_2, 1
// ; %q_1 = or i32 %carry_1, %tmp8
// ; %tmp9 = sub i32 %tmp4, %tmp7
// ; %tmp10 = ashr i32 %tmp9, 31
// ; %carry = and i32 %tmp10, 1
// ; %tmp11 = and i32 %tmp10, %divisor
// ; %r = sub i32 %tmp7, %tmp11
// ; %sr_2 = add i32 %sr_3, -1
// ; %tmp12 = icmp eq i32 %sr_2, 0
// ; br i1 %tmp12, label %loop-exit, label %do-while
Builder.SetInsertPoint(DoWhile);
PHINode *Carry_1 = Builder.CreatePHI(DivTy, 2);
PHINode *SR_3 = Builder.CreatePHI(DivTy, 2);
PHINode *R_1 = Builder.CreatePHI(DivTy, 2);
PHINode *Q_2 = Builder.CreatePHI(DivTy, 2);
Value *Tmp5 = Builder.CreateShl(R_1, One);
Value *Tmp6 = Builder.CreateLShr(Q_2, MSB);
Value *Tmp7 = Builder.CreateOr(Tmp5, Tmp6);
Value *Tmp8 = Builder.CreateShl(Q_2, One);
Value *Q_1 = Builder.CreateOr(Carry_1, Tmp8);
Value *Tmp9 = Builder.CreateSub(Tmp4, Tmp7);
Value *Tmp10 = Builder.CreateAShr(Tmp9, MSB);
Value *Carry = Builder.CreateAnd(Tmp10, One);
Value *Tmp11 = Builder.CreateAnd(Tmp10, Divisor);
Value *R = Builder.CreateSub(Tmp7, Tmp11);
Value *SR_2 = Builder.CreateAdd(SR_3, NegOne);
Value *Tmp12 = Builder.CreateICmpEQ(SR_2, Zero);
Builder.CreateCondBr(Tmp12, LoopExit, DoWhile);
// ; loop-exit: ; preds = %do-while, %bb1
// ; %carry_2 = phi i32 [ 0, %bb1 ], [ %carry, %do-while ]
// ; %q_3 = phi i32 [ %q, %bb1 ], [ %q_1, %do-while ]
// ; %tmp13 = shl i32 %q_3, 1
// ; %q_4 = or i32 %carry_2, %tmp13
// ; br label %end
Builder.SetInsertPoint(LoopExit);
PHINode *Carry_2 = Builder.CreatePHI(DivTy, 2);
PHINode *Q_3 = Builder.CreatePHI(DivTy, 2);
Value *Tmp13 = Builder.CreateShl(Q_3, One);
Value *Q_4 = Builder.CreateOr(Carry_2, Tmp13);
Builder.CreateBr(End);
// ; end: ; preds = %loop-exit, %special-cases
// ; %q_5 = phi i32 [ %q_4, %loop-exit ], [ %retVal, %special-cases ]
// ; ret i32 %q_5
Builder.SetInsertPoint(End, End->begin());
PHINode *Q_5 = Builder.CreatePHI(DivTy, 2);
// Populate the Phis, since all values have now been created. Our Phis were:
// ; %carry_1 = phi i32 [ 0, %preheader ], [ %carry, %do-while ]
Carry_1->addIncoming(Zero, Preheader);
Carry_1->addIncoming(Carry, DoWhile);
// ; %sr_3 = phi i32 [ %sr_1, %preheader ], [ %sr_2, %do-while ]
SR_3->addIncoming(SR_1, Preheader);
SR_3->addIncoming(SR_2, DoWhile);
// ; %r_1 = phi i32 [ %tmp3, %preheader ], [ %r, %do-while ]
R_1->addIncoming(Tmp3, Preheader);
R_1->addIncoming(R, DoWhile);
// ; %q_2 = phi i32 [ %q, %preheader ], [ %q_1, %do-while ]
Q_2->addIncoming(Q, Preheader);
Q_2->addIncoming(Q_1, DoWhile);
// ; %carry_2 = phi i32 [ 0, %bb1 ], [ %carry, %do-while ]
Carry_2->addIncoming(Zero, BB1);
Carry_2->addIncoming(Carry, DoWhile);
// ; %q_3 = phi i32 [ %q, %bb1 ], [ %q_1, %do-while ]
Q_3->addIncoming(Q, BB1);
Q_3->addIncoming(Q_1, DoWhile);
// ; %q_5 = phi i32 [ %q_4, %loop-exit ], [ %retVal, %special-cases ]
Q_5->addIncoming(Q_4, LoopExit);
Q_5->addIncoming(RetVal, SpecialCases);
return Q_5;
}
/// Generate code to calculate the remainder of two integers, replacing Rem with
/// the generated code. This currently generates code using the udiv expansion,
/// but future work includes generating more specialized code, e.g. when more
/// information about the operands are known. Implements both 32bit and 64bit
/// scalar division.
///
/// @brief Replace Rem with generated code.
bool llvm::expandRemainder(BinaryOperator *Rem) {
assert((Rem->getOpcode() == Instruction::SRem ||
Rem->getOpcode() == Instruction::URem) &&
"Trying to expand remainder from a non-remainder function");
IRBuilder<> Builder(Rem);
Type *RemTy = Rem->getType();
if (RemTy->isVectorTy())
llvm_unreachable("Div over vectors not supported");
unsigned RemTyBitWidth = RemTy->getIntegerBitWidth();
if (RemTyBitWidth != 32 && RemTyBitWidth != 64)
llvm_unreachable("Div of bitwidth other than 32 or 64 not supported");
// First prepare the sign if it's a signed remainder
if (Rem->getOpcode() == Instruction::SRem) {
Value *Remainder = generateSignedRemainderCode(Rem->getOperand(0),
Rem->getOperand(1), Builder);
Rem->replaceAllUsesWith(Remainder);
Rem->dropAllReferences();
Rem->eraseFromParent();
// If we didn't actually generate an urem instruction, we're done
// This happens for example if the input were constant. In this case the
// Builder insertion point was unchanged
if (Rem == Builder.GetInsertPoint())
return true;
BinaryOperator *BO = dyn_cast<BinaryOperator>(Builder.GetInsertPoint());
Rem = BO;
}
Value *Remainder = generatedUnsignedRemainderCode(Rem->getOperand(0),
Rem->getOperand(1),
Builder);
Rem->replaceAllUsesWith(Remainder);
Rem->dropAllReferences();
Rem->eraseFromParent();
// Expand the udiv
if (BinaryOperator *UDiv = dyn_cast<BinaryOperator>(Builder.GetInsertPoint())) {
assert(UDiv->getOpcode() == Instruction::UDiv && "Non-udiv in expansion?");
expandDivision(UDiv);
}
return true;
}
/// Generate code to divide two integers, replacing Div with the generated
/// code. This currently generates code similarly to compiler-rt's
/// implementations, but future work includes generating more specialized code
/// when more information about the operands are known. Implements both
/// 32bit and 64bit scalar division.
///
/// @brief Replace Div with generated code.
bool llvm::expandDivision(BinaryOperator *Div) {
assert((Div->getOpcode() == Instruction::SDiv ||
Div->getOpcode() == Instruction::UDiv) &&
"Trying to expand division from a non-division function");
IRBuilder<> Builder(Div);
Type *DivTy = Div->getType();
if (DivTy->isVectorTy())
llvm_unreachable("Div over vectors not supported");
unsigned DivTyBitWidth = DivTy->getIntegerBitWidth();
if (DivTyBitWidth != 32 && DivTyBitWidth != 64)
llvm_unreachable("Div of bitwidth other than 32 or 64 not supported");
// First prepare the sign if it's a signed division
if (Div->getOpcode() == Instruction::SDiv) {
// Lower the code to unsigned division, and reset Div to point to the udiv.
Value *Quotient = generateSignedDivisionCode(Div->getOperand(0),
Div->getOperand(1), Builder);
Div->replaceAllUsesWith(Quotient);
Div->dropAllReferences();
Div->eraseFromParent();
// If we didn't actually generate an udiv instruction, we're done
// This happens for example if the input were constant. In this case the
// Builder insertion point was unchanged
if (Div == Builder.GetInsertPoint())
return true;
BinaryOperator *BO = dyn_cast<BinaryOperator>(Builder.GetInsertPoint());
Div = BO;
}
// Insert the unsigned division code
Value *Quotient = generateUnsignedDivisionCode(Div->getOperand(0),
Div->getOperand(1),
Builder);
Div->replaceAllUsesWith(Quotient);
Div->dropAllReferences();
Div->eraseFromParent();
return true;
}
/// Generate code to compute the remainder of two integers of bitwidth up to
/// 32 bits. Uses the above routines and extends the inputs/truncates the
/// outputs to operate in 32 bits; that is, these routines are good for targets
/// that have no or very little suppport for smaller than 32 bit integer
/// arithmetic.
///
/// @brief Replace Rem with emulation code.
bool llvm::expandRemainderUpTo32Bits(BinaryOperator *Rem) {
assert((Rem->getOpcode() == Instruction::SRem ||
Rem->getOpcode() == Instruction::URem) &&
"Trying to expand remainder from a non-remainder function");
Type *RemTy = Rem->getType();
if (RemTy->isVectorTy())
llvm_unreachable("Div over vectors not supported");
unsigned RemTyBitWidth = RemTy->getIntegerBitWidth();
if (RemTyBitWidth > 32)
llvm_unreachable("Div of bitwidth greater than 32 not supported");
if (RemTyBitWidth == 32)
return expandRemainder(Rem);
// If bitwidth smaller than 32 extend inputs, extend output and proceed
// with 32 bit division.
IRBuilder<> Builder(Rem);
Value *ExtDividend;
Value *ExtDivisor;
Value *ExtRem;
Value *Trunc;
Type *Int32Ty = Builder.getInt32Ty();
if (Rem->getOpcode() == Instruction::SRem) {
ExtDividend = Builder.CreateSExt(Rem->getOperand(0), Int32Ty);
ExtDivisor = Builder.CreateSExt(Rem->getOperand(1), Int32Ty);
ExtRem = Builder.CreateSRem(ExtDividend, ExtDivisor);
} else {
ExtDividend = Builder.CreateZExt(Rem->getOperand(0), Int32Ty);
ExtDivisor = Builder.CreateZExt(Rem->getOperand(1), Int32Ty);
ExtRem = Builder.CreateURem(ExtDividend, ExtDivisor);
}
Trunc = Builder.CreateTrunc(ExtRem, RemTy);
Rem->replaceAllUsesWith(Trunc);
Rem->dropAllReferences();
Rem->eraseFromParent();
return expandRemainder(cast<BinaryOperator>(ExtRem));
}
/// Generate code to compute the remainder of two integers of bitwidth up to
/// 64 bits. Uses the above routines and extends the inputs/truncates the
/// outputs to operate in 64 bits.
///
/// @brief Replace Rem with emulation code.
bool llvm::expandRemainderUpTo64Bits(BinaryOperator *Rem) {
assert((Rem->getOpcode() == Instruction::SRem ||
Rem->getOpcode() == Instruction::URem) &&
"Trying to expand remainder from a non-remainder function");
Type *RemTy = Rem->getType();
if (RemTy->isVectorTy())
llvm_unreachable("Div over vectors not supported");
unsigned RemTyBitWidth = RemTy->getIntegerBitWidth();
if (RemTyBitWidth > 64)
llvm_unreachable("Div of bitwidth greater than 64 not supported");
if (RemTyBitWidth == 64)
return expandRemainder(Rem);
// If bitwidth smaller than 64 extend inputs, extend output and proceed
// with 64 bit division.
IRBuilder<> Builder(Rem);
Value *ExtDividend;
Value *ExtDivisor;
Value *ExtRem;
Value *Trunc;
Type *Int64Ty = Builder.getInt64Ty();
if (Rem->getOpcode() == Instruction::SRem) {
ExtDividend = Builder.CreateSExt(Rem->getOperand(0), Int64Ty);
ExtDivisor = Builder.CreateSExt(Rem->getOperand(1), Int64Ty);
ExtRem = Builder.CreateSRem(ExtDividend, ExtDivisor);
} else {
ExtDividend = Builder.CreateZExt(Rem->getOperand(0), Int64Ty);
ExtDivisor = Builder.CreateZExt(Rem->getOperand(1), Int64Ty);
ExtRem = Builder.CreateURem(ExtDividend, ExtDivisor);
}
Trunc = Builder.CreateTrunc(ExtRem, RemTy);
Rem->replaceAllUsesWith(Trunc);
Rem->dropAllReferences();
Rem->eraseFromParent();
return expandRemainder(cast<BinaryOperator>(ExtRem));
}
/// Generate code to divide two integers of bitwidth up to 32 bits. Uses the
/// above routines and extends the inputs/truncates the outputs to operate
/// in 32 bits; that is, these routines are good for targets that have no
/// or very little support for smaller than 32 bit integer arithmetic.
///
/// @brief Replace Div with emulation code.
bool llvm::expandDivisionUpTo32Bits(BinaryOperator *Div) {
assert((Div->getOpcode() == Instruction::SDiv ||
Div->getOpcode() == Instruction::UDiv) &&
"Trying to expand division from a non-division function");
Type *DivTy = Div->getType();
if (DivTy->isVectorTy())
llvm_unreachable("Div over vectors not supported");
unsigned DivTyBitWidth = DivTy->getIntegerBitWidth();
if (DivTyBitWidth > 32)
llvm_unreachable("Div of bitwidth greater than 32 not supported");
if (DivTyBitWidth == 32)
return expandDivision(Div);
// If bitwidth smaller than 32 extend inputs, extend output and proceed
// with 32 bit division.
IRBuilder<> Builder(Div);
Value *ExtDividend;
Value *ExtDivisor;
Value *ExtDiv;
Value *Trunc;
Type *Int32Ty = Builder.getInt32Ty();
if (Div->getOpcode() == Instruction::SDiv) {
ExtDividend = Builder.CreateSExt(Div->getOperand(0), Int32Ty);
ExtDivisor = Builder.CreateSExt(Div->getOperand(1), Int32Ty);
ExtDiv = Builder.CreateSDiv(ExtDividend, ExtDivisor);
} else {
ExtDividend = Builder.CreateZExt(Div->getOperand(0), Int32Ty);
ExtDivisor = Builder.CreateZExt(Div->getOperand(1), Int32Ty);
ExtDiv = Builder.CreateUDiv(ExtDividend, ExtDivisor);
}
Trunc = Builder.CreateTrunc(ExtDiv, DivTy);
Div->replaceAllUsesWith(Trunc);
Div->dropAllReferences();
Div->eraseFromParent();
return expandDivision(cast<BinaryOperator>(ExtDiv));
}
/// Generate code to divide two integers of bitwidth up to 64 bits. Uses the
/// above routines and extends the inputs/truncates the outputs to operate
/// in 64 bits.
///
/// @brief Replace Div with emulation code.
bool llvm::expandDivisionUpTo64Bits(BinaryOperator *Div) {
assert((Div->getOpcode() == Instruction::SDiv ||
Div->getOpcode() == Instruction::UDiv) &&
"Trying to expand division from a non-division function");
Type *DivTy = Div->getType();
if (DivTy->isVectorTy())
llvm_unreachable("Div over vectors not supported");
unsigned DivTyBitWidth = DivTy->getIntegerBitWidth();
if (DivTyBitWidth > 64)
llvm_unreachable("Div of bitwidth greater than 64 not supported");
if (DivTyBitWidth == 64)
return expandDivision(Div);
// If bitwidth smaller than 64 extend inputs, extend output and proceed
// with 64 bit division.
IRBuilder<> Builder(Div);
Value *ExtDividend;
Value *ExtDivisor;
Value *ExtDiv;
Value *Trunc;
Type *Int64Ty = Builder.getInt64Ty();
if (Div->getOpcode() == Instruction::SDiv) {
ExtDividend = Builder.CreateSExt(Div->getOperand(0), Int64Ty);
ExtDivisor = Builder.CreateSExt(Div->getOperand(1), Int64Ty);
ExtDiv = Builder.CreateSDiv(ExtDividend, ExtDivisor);
} else {
ExtDividend = Builder.CreateZExt(Div->getOperand(0), Int64Ty);
ExtDivisor = Builder.CreateZExt(Div->getOperand(1), Int64Ty);
ExtDiv = Builder.CreateUDiv(ExtDividend, ExtDivisor);
}
Trunc = Builder.CreateTrunc(ExtDiv, DivTy);
Div->replaceAllUsesWith(Trunc);
Div->dropAllReferences();
Div->eraseFromParent();
return expandDivision(cast<BinaryOperator>(ExtDiv));
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/BuildLibCalls.cpp | //===- BuildLibCalls.cpp - Utility builder for libcalls -------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements some functions that will create standard C libcalls.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/BuildLibCalls.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Type.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
using namespace llvm;
/// CastToCStr - Return V if it is an i8*, otherwise cast it to i8*.
Value *llvm::CastToCStr(Value *V, IRBuilder<> &B) {
unsigned AS = V->getType()->getPointerAddressSpace();
return B.CreateBitCast(V, B.getInt8PtrTy(AS), "cstr");
}
/// EmitStrLen - Emit a call to the strlen function to the builder, for the
/// specified pointer. This always returns an integer value of size intptr_t.
Value *llvm::EmitStrLen(Value *Ptr, IRBuilder<> &B, const DataLayout &DL,
const TargetLibraryInfo *TLI) {
if (!TLI->has(LibFunc::strlen))
return nullptr;
Module *M = B.GetInsertBlock()->getParent()->getParent();
AttributeSet AS[2];
AS[0] = AttributeSet::get(M->getContext(), 1, Attribute::NoCapture);
Attribute::AttrKind AVs[2] = { Attribute::ReadOnly, Attribute::NoUnwind };
AS[1] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, AVs);
LLVMContext &Context = B.GetInsertBlock()->getContext();
Constant *StrLen = M->getOrInsertFunction(
"strlen", AttributeSet::get(M->getContext(), AS),
DL.getIntPtrType(Context), B.getInt8PtrTy(), nullptr);
CallInst *CI = B.CreateCall(StrLen, CastToCStr(Ptr, B), "strlen");
if (const Function *F = dyn_cast<Function>(StrLen->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
/// EmitStrNLen - Emit a call to the strnlen function to the builder, for the
/// specified pointer. Ptr is required to be some pointer type, MaxLen must
/// be of size_t type, and the return value has 'intptr_t' type.
Value *llvm::EmitStrNLen(Value *Ptr, Value *MaxLen, IRBuilder<> &B,
const DataLayout &DL, const TargetLibraryInfo *TLI) {
if (!TLI->has(LibFunc::strnlen))
return nullptr;
Module *M = B.GetInsertBlock()->getParent()->getParent();
AttributeSet AS[2];
AS[0] = AttributeSet::get(M->getContext(), 1, Attribute::NoCapture);
Attribute::AttrKind AVs[2] = { Attribute::ReadOnly, Attribute::NoUnwind };
AS[1] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, AVs);
LLVMContext &Context = B.GetInsertBlock()->getContext();
Constant *StrNLen =
M->getOrInsertFunction("strnlen", AttributeSet::get(M->getContext(), AS),
DL.getIntPtrType(Context), B.getInt8PtrTy(),
DL.getIntPtrType(Context), nullptr);
CallInst *CI = B.CreateCall(StrNLen, {CastToCStr(Ptr, B), MaxLen}, "strnlen");
if (const Function *F = dyn_cast<Function>(StrNLen->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
/// EmitStrChr - Emit a call to the strchr function to the builder, for the
/// specified pointer and character. Ptr is required to be some pointer type,
/// and the return value has 'i8*' type.
Value *llvm::EmitStrChr(Value *Ptr, char C, IRBuilder<> &B,
const TargetLibraryInfo *TLI) {
if (!TLI->has(LibFunc::strchr))
return nullptr;
Module *M = B.GetInsertBlock()->getParent()->getParent();
Attribute::AttrKind AVs[2] = { Attribute::ReadOnly, Attribute::NoUnwind };
AttributeSet AS =
AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, AVs);
Type *I8Ptr = B.getInt8PtrTy();
Type *I32Ty = B.getInt32Ty();
Constant *StrChr = M->getOrInsertFunction("strchr",
AttributeSet::get(M->getContext(),
AS),
I8Ptr, I8Ptr, I32Ty, nullptr);
CallInst *CI = B.CreateCall(
StrChr, {CastToCStr(Ptr, B), ConstantInt::get(I32Ty, C)}, "strchr");
if (const Function *F = dyn_cast<Function>(StrChr->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
/// EmitStrNCmp - Emit a call to the strncmp function to the builder.
Value *llvm::EmitStrNCmp(Value *Ptr1, Value *Ptr2, Value *Len, IRBuilder<> &B,
const DataLayout &DL, const TargetLibraryInfo *TLI) {
if (!TLI->has(LibFunc::strncmp))
return nullptr;
Module *M = B.GetInsertBlock()->getParent()->getParent();
AttributeSet AS[3];
AS[0] = AttributeSet::get(M->getContext(), 1, Attribute::NoCapture);
AS[1] = AttributeSet::get(M->getContext(), 2, Attribute::NoCapture);
Attribute::AttrKind AVs[2] = { Attribute::ReadOnly, Attribute::NoUnwind };
AS[2] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, AVs);
LLVMContext &Context = B.GetInsertBlock()->getContext();
Value *StrNCmp = M->getOrInsertFunction(
"strncmp", AttributeSet::get(M->getContext(), AS), B.getInt32Ty(),
B.getInt8PtrTy(), B.getInt8PtrTy(), DL.getIntPtrType(Context), nullptr);
CallInst *CI = B.CreateCall(
StrNCmp, {CastToCStr(Ptr1, B), CastToCStr(Ptr2, B), Len}, "strncmp");
if (const Function *F = dyn_cast<Function>(StrNCmp->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
/// EmitStrCpy - Emit a call to the strcpy function to the builder, for the
/// specified pointer arguments.
Value *llvm::EmitStrCpy(Value *Dst, Value *Src, IRBuilder<> &B,
const TargetLibraryInfo *TLI, StringRef Name) {
if (!TLI->has(LibFunc::strcpy))
return nullptr;
Module *M = B.GetInsertBlock()->getParent()->getParent();
AttributeSet AS[2];
AS[0] = AttributeSet::get(M->getContext(), 2, Attribute::NoCapture);
AS[1] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex,
Attribute::NoUnwind);
Type *I8Ptr = B.getInt8PtrTy();
Value *StrCpy = M->getOrInsertFunction(Name,
AttributeSet::get(M->getContext(), AS),
I8Ptr, I8Ptr, I8Ptr, nullptr);
CallInst *CI =
B.CreateCall(StrCpy, {CastToCStr(Dst, B), CastToCStr(Src, B)}, Name);
if (const Function *F = dyn_cast<Function>(StrCpy->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
/// EmitStrNCpy - Emit a call to the strncpy function to the builder, for the
/// specified pointer arguments.
Value *llvm::EmitStrNCpy(Value *Dst, Value *Src, Value *Len, IRBuilder<> &B,
const TargetLibraryInfo *TLI, StringRef Name) {
if (!TLI->has(LibFunc::strncpy))
return nullptr;
Module *M = B.GetInsertBlock()->getParent()->getParent();
AttributeSet AS[2];
AS[0] = AttributeSet::get(M->getContext(), 2, Attribute::NoCapture);
AS[1] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex,
Attribute::NoUnwind);
Type *I8Ptr = B.getInt8PtrTy();
Value *StrNCpy = M->getOrInsertFunction(Name,
AttributeSet::get(M->getContext(),
AS),
I8Ptr, I8Ptr, I8Ptr,
Len->getType(), nullptr);
CallInst *CI = B.CreateCall(
StrNCpy, {CastToCStr(Dst, B), CastToCStr(Src, B), Len}, "strncpy");
if (const Function *F = dyn_cast<Function>(StrNCpy->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
/// EmitMemCpyChk - Emit a call to the __memcpy_chk function to the builder.
/// This expects that the Len and ObjSize have type 'intptr_t' and Dst/Src
/// are pointers.
Value *llvm::EmitMemCpyChk(Value *Dst, Value *Src, Value *Len, Value *ObjSize,
IRBuilder<> &B, const DataLayout &DL,
const TargetLibraryInfo *TLI) {
if (!TLI->has(LibFunc::memcpy_chk))
return nullptr;
Module *M = B.GetInsertBlock()->getParent()->getParent();
AttributeSet AS;
AS = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex,
Attribute::NoUnwind);
LLVMContext &Context = B.GetInsertBlock()->getContext();
Value *MemCpy = M->getOrInsertFunction(
"__memcpy_chk", AttributeSet::get(M->getContext(), AS), B.getInt8PtrTy(),
B.getInt8PtrTy(), B.getInt8PtrTy(), DL.getIntPtrType(Context),
DL.getIntPtrType(Context), nullptr);
Dst = CastToCStr(Dst, B);
Src = CastToCStr(Src, B);
CallInst *CI = B.CreateCall(MemCpy, {Dst, Src, Len, ObjSize});
if (const Function *F = dyn_cast<Function>(MemCpy->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
/// EmitMemChr - Emit a call to the memchr function. This assumes that Ptr is
/// a pointer, Val is an i32 value, and Len is an 'intptr_t' value.
Value *llvm::EmitMemChr(Value *Ptr, Value *Val, Value *Len, IRBuilder<> &B,
const DataLayout &DL, const TargetLibraryInfo *TLI) {
if (!TLI->has(LibFunc::memchr))
return nullptr;
Module *M = B.GetInsertBlock()->getParent()->getParent();
AttributeSet AS;
Attribute::AttrKind AVs[2] = { Attribute::ReadOnly, Attribute::NoUnwind };
AS = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, AVs);
LLVMContext &Context = B.GetInsertBlock()->getContext();
Value *MemChr = M->getOrInsertFunction(
"memchr", AttributeSet::get(M->getContext(), AS), B.getInt8PtrTy(),
B.getInt8PtrTy(), B.getInt32Ty(), DL.getIntPtrType(Context), nullptr);
CallInst *CI = B.CreateCall(MemChr, {CastToCStr(Ptr, B), Val, Len}, "memchr");
if (const Function *F = dyn_cast<Function>(MemChr->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
/// EmitMemCmp - Emit a call to the memcmp function.
Value *llvm::EmitMemCmp(Value *Ptr1, Value *Ptr2, Value *Len, IRBuilder<> &B,
const DataLayout &DL, const TargetLibraryInfo *TLI) {
if (!TLI->has(LibFunc::memcmp))
return nullptr;
Module *M = B.GetInsertBlock()->getParent()->getParent();
AttributeSet AS[3];
AS[0] = AttributeSet::get(M->getContext(), 1, Attribute::NoCapture);
AS[1] = AttributeSet::get(M->getContext(), 2, Attribute::NoCapture);
Attribute::AttrKind AVs[2] = { Attribute::ReadOnly, Attribute::NoUnwind };
AS[2] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, AVs);
LLVMContext &Context = B.GetInsertBlock()->getContext();
Value *MemCmp = M->getOrInsertFunction(
"memcmp", AttributeSet::get(M->getContext(), AS), B.getInt32Ty(),
B.getInt8PtrTy(), B.getInt8PtrTy(), DL.getIntPtrType(Context), nullptr);
CallInst *CI = B.CreateCall(
MemCmp, {CastToCStr(Ptr1, B), CastToCStr(Ptr2, B), Len}, "memcmp");
if (const Function *F = dyn_cast<Function>(MemCmp->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
/// Append a suffix to the function name according to the type of 'Op'.
static void AppendTypeSuffix(Value *Op, StringRef &Name, SmallString<20> &NameBuffer) {
if (!Op->getType()->isDoubleTy()) {
NameBuffer += Name;
if (Op->getType()->isFloatTy())
NameBuffer += 'f';
else
NameBuffer += 'l';
Name = NameBuffer;
}
return;
}
/// EmitUnaryFloatFnCall - Emit a call to the unary function named 'Name' (e.g.
/// 'floor'). This function is known to take a single of type matching 'Op' and
/// returns one value with the same type. If 'Op' is a long double, 'l' is
/// added as the suffix of name, if 'Op' is a float, we add a 'f' suffix.
Value *llvm::EmitUnaryFloatFnCall(Value *Op, StringRef Name, IRBuilder<> &B,
const AttributeSet &Attrs) {
SmallString<20> NameBuffer;
AppendTypeSuffix(Op, Name, NameBuffer);
Module *M = B.GetInsertBlock()->getParent()->getParent();
Value *Callee = M->getOrInsertFunction(Name, Op->getType(),
Op->getType(), nullptr);
CallInst *CI = B.CreateCall(Callee, Op, Name);
CI->setAttributes(Attrs);
if (const Function *F = dyn_cast<Function>(Callee->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
/// EmitBinaryFloatFnCall - Emit a call to the binary function named 'Name'
/// (e.g. 'fmin'). This function is known to take type matching 'Op1' and 'Op2'
/// and return one value with the same type. If 'Op1/Op2' are long double, 'l'
/// is added as the suffix of name, if 'Op1/Op2' is a float, we add a 'f'
/// suffix.
Value *llvm::EmitBinaryFloatFnCall(Value *Op1, Value *Op2, StringRef Name,
IRBuilder<> &B, const AttributeSet &Attrs) {
SmallString<20> NameBuffer;
AppendTypeSuffix(Op1, Name, NameBuffer);
Module *M = B.GetInsertBlock()->getParent()->getParent();
Value *Callee = M->getOrInsertFunction(Name, Op1->getType(),
Op1->getType(), Op2->getType(), nullptr);
CallInst *CI = B.CreateCall(Callee, {Op1, Op2}, Name);
CI->setAttributes(Attrs);
if (const Function *F = dyn_cast<Function>(Callee->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
/// EmitPutChar - Emit a call to the putchar function. This assumes that Char
/// is an integer.
Value *llvm::EmitPutChar(Value *Char, IRBuilder<> &B,
const TargetLibraryInfo *TLI) {
if (!TLI->has(LibFunc::putchar))
return nullptr;
Module *M = B.GetInsertBlock()->getParent()->getParent();
Value *PutChar = M->getOrInsertFunction("putchar", B.getInt32Ty(),
B.getInt32Ty(), nullptr);
CallInst *CI = B.CreateCall(PutChar,
B.CreateIntCast(Char,
B.getInt32Ty(),
/*isSigned*/true,
"chari"),
"putchar");
if (const Function *F = dyn_cast<Function>(PutChar->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
/// EmitPutS - Emit a call to the puts function. This assumes that Str is
/// some pointer.
Value *llvm::EmitPutS(Value *Str, IRBuilder<> &B,
const TargetLibraryInfo *TLI) {
if (!TLI->has(LibFunc::puts))
return nullptr;
Module *M = B.GetInsertBlock()->getParent()->getParent();
AttributeSet AS[2];
AS[0] = AttributeSet::get(M->getContext(), 1, Attribute::NoCapture);
AS[1] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex,
Attribute::NoUnwind);
Value *PutS = M->getOrInsertFunction("puts",
AttributeSet::get(M->getContext(), AS),
B.getInt32Ty(),
B.getInt8PtrTy(),
nullptr);
CallInst *CI = B.CreateCall(PutS, CastToCStr(Str, B), "puts");
if (const Function *F = dyn_cast<Function>(PutS->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
/// EmitFPutC - Emit a call to the fputc function. This assumes that Char is
/// an integer and File is a pointer to FILE.
Value *llvm::EmitFPutC(Value *Char, Value *File, IRBuilder<> &B,
const TargetLibraryInfo *TLI) {
if (!TLI->has(LibFunc::fputc))
return nullptr;
Module *M = B.GetInsertBlock()->getParent()->getParent();
AttributeSet AS[2];
AS[0] = AttributeSet::get(M->getContext(), 2, Attribute::NoCapture);
AS[1] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex,
Attribute::NoUnwind);
Constant *F;
if (File->getType()->isPointerTy())
F = M->getOrInsertFunction("fputc",
AttributeSet::get(M->getContext(), AS),
B.getInt32Ty(),
B.getInt32Ty(), File->getType(),
nullptr);
else
F = M->getOrInsertFunction("fputc",
B.getInt32Ty(),
B.getInt32Ty(),
File->getType(), nullptr);
Char = B.CreateIntCast(Char, B.getInt32Ty(), /*isSigned*/true,
"chari");
CallInst *CI = B.CreateCall(F, {Char, File}, "fputc");
if (const Function *Fn = dyn_cast<Function>(F->stripPointerCasts()))
CI->setCallingConv(Fn->getCallingConv());
return CI;
}
/// EmitFPutS - Emit a call to the puts function. Str is required to be a
/// pointer and File is a pointer to FILE.
Value *llvm::EmitFPutS(Value *Str, Value *File, IRBuilder<> &B,
const TargetLibraryInfo *TLI) {
if (!TLI->has(LibFunc::fputs))
return nullptr;
Module *M = B.GetInsertBlock()->getParent()->getParent();
AttributeSet AS[3];
AS[0] = AttributeSet::get(M->getContext(), 1, Attribute::NoCapture);
AS[1] = AttributeSet::get(M->getContext(), 2, Attribute::NoCapture);
AS[2] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex,
Attribute::NoUnwind);
StringRef FPutsName = TLI->getName(LibFunc::fputs);
Constant *F;
if (File->getType()->isPointerTy())
F = M->getOrInsertFunction(FPutsName,
AttributeSet::get(M->getContext(), AS),
B.getInt32Ty(),
B.getInt8PtrTy(),
File->getType(), nullptr);
else
F = M->getOrInsertFunction(FPutsName, B.getInt32Ty(),
B.getInt8PtrTy(),
File->getType(), nullptr);
CallInst *CI = B.CreateCall(F, {CastToCStr(Str, B), File}, "fputs");
if (const Function *Fn = dyn_cast<Function>(F->stripPointerCasts()))
CI->setCallingConv(Fn->getCallingConv());
return CI;
}
/// EmitFWrite - Emit a call to the fwrite function. This assumes that Ptr is
/// a pointer, Size is an 'intptr_t', and File is a pointer to FILE.
Value *llvm::EmitFWrite(Value *Ptr, Value *Size, Value *File, IRBuilder<> &B,
const DataLayout &DL, const TargetLibraryInfo *TLI) {
if (!TLI->has(LibFunc::fwrite))
return nullptr;
Module *M = B.GetInsertBlock()->getParent()->getParent();
AttributeSet AS[3];
AS[0] = AttributeSet::get(M->getContext(), 1, Attribute::NoCapture);
AS[1] = AttributeSet::get(M->getContext(), 4, Attribute::NoCapture);
AS[2] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex,
Attribute::NoUnwind);
LLVMContext &Context = B.GetInsertBlock()->getContext();
StringRef FWriteName = TLI->getName(LibFunc::fwrite);
Constant *F;
if (File->getType()->isPointerTy())
F = M->getOrInsertFunction(
FWriteName, AttributeSet::get(M->getContext(), AS),
DL.getIntPtrType(Context), B.getInt8PtrTy(), DL.getIntPtrType(Context),
DL.getIntPtrType(Context), File->getType(), nullptr);
else
F = M->getOrInsertFunction(FWriteName, DL.getIntPtrType(Context),
B.getInt8PtrTy(), DL.getIntPtrType(Context),
DL.getIntPtrType(Context), File->getType(),
nullptr);
CallInst *CI =
B.CreateCall(F, {CastToCStr(Ptr, B), Size,
ConstantInt::get(DL.getIntPtrType(Context), 1), File});
if (const Function *Fn = dyn_cast<Function>(F->stripPointerCasts()))
CI->setCallingConv(Fn->getCallingConv());
return CI;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/CodeExtractor.cpp | //===- CodeExtractor.cpp - Pull code region into a new function -----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the interface to tear out a code region, such as an
// individual loop or a parallel section, into a new function, replacing it with
// a call to the new function.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/CodeExtractor.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/RegionInfo.h"
#include "llvm/Analysis/RegionIterator.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Verifier.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include <algorithm>
#include <set>
using namespace llvm;
#define DEBUG_TYPE "code-extractor"
// Provide a command-line option to aggregate function arguments into a struct
// for functions produced by the code extractor. This is useful when converting
// extracted functions to pthread-based code, as only one argument (void*) can
// be passed in to pthread_create().
static cl::opt<bool>
AggregateArgsOpt("aggregate-extracted-args", cl::Hidden,
cl::desc("Aggregate arguments to code-extracted functions"));
/// \brief Test whether a block is valid for extraction.
static bool isBlockValidForExtraction(const BasicBlock &BB) {
// Landing pads must be in the function where they were inserted for cleanup.
if (BB.isLandingPad())
return false;
// Don't hoist code containing allocas, invokes, or vastarts.
for (BasicBlock::const_iterator I = BB.begin(), E = BB.end(); I != E; ++I) {
if (isa<AllocaInst>(I) || isa<InvokeInst>(I))
return false;
if (const CallInst *CI = dyn_cast<CallInst>(I))
if (const Function *F = CI->getCalledFunction())
if (F->getIntrinsicID() == Intrinsic::vastart)
return false;
}
return true;
}
/// \brief Build a set of blocks to extract if the input blocks are viable.
template <typename IteratorT>
static SetVector<BasicBlock *> buildExtractionBlockSet(IteratorT BBBegin,
IteratorT BBEnd) {
SetVector<BasicBlock *> Result;
assert(BBBegin != BBEnd);
// Loop over the blocks, adding them to our set-vector, and aborting with an
// empty set if we encounter invalid blocks.
for (IteratorT I = BBBegin, E = BBEnd; I != E; ++I) {
if (!Result.insert(*I))
llvm_unreachable("Repeated basic blocks in extraction input");
if (!isBlockValidForExtraction(**I)) {
Result.clear();
return Result;
}
}
#ifndef NDEBUG
for (SetVector<BasicBlock *>::iterator I = std::next(Result.begin()),
E = Result.end();
I != E; ++I)
for (pred_iterator PI = pred_begin(*I), PE = pred_end(*I);
PI != PE; ++PI)
assert(Result.count(*PI) &&
"No blocks in this region may have entries from outside the region"
" except for the first block!");
#endif
return Result;
}
/// \brief Helper to call buildExtractionBlockSet with an ArrayRef.
static SetVector<BasicBlock *>
buildExtractionBlockSet(ArrayRef<BasicBlock *> BBs) {
return buildExtractionBlockSet(BBs.begin(), BBs.end());
}
/// \brief Helper to call buildExtractionBlockSet with a RegionNode.
static SetVector<BasicBlock *>
buildExtractionBlockSet(const RegionNode &RN) {
if (!RN.isSubRegion())
// Just a single BasicBlock.
return buildExtractionBlockSet(RN.getNodeAs<BasicBlock>());
const Region &R = *RN.getNodeAs<Region>();
return buildExtractionBlockSet(R.block_begin(), R.block_end());
}
CodeExtractor::CodeExtractor(BasicBlock *BB, bool AggregateArgs)
: DT(nullptr), AggregateArgs(AggregateArgs||AggregateArgsOpt),
Blocks(buildExtractionBlockSet(BB)), NumExitBlocks(~0U) {}
CodeExtractor::CodeExtractor(ArrayRef<BasicBlock *> BBs, DominatorTree *DT,
bool AggregateArgs)
: DT(DT), AggregateArgs(AggregateArgs||AggregateArgsOpt),
Blocks(buildExtractionBlockSet(BBs)), NumExitBlocks(~0U) {}
CodeExtractor::CodeExtractor(DominatorTree &DT, Loop &L, bool AggregateArgs)
: DT(&DT), AggregateArgs(AggregateArgs||AggregateArgsOpt),
Blocks(buildExtractionBlockSet(L.getBlocks())), NumExitBlocks(~0U) {}
CodeExtractor::CodeExtractor(DominatorTree &DT, const RegionNode &RN,
bool AggregateArgs)
: DT(&DT), AggregateArgs(AggregateArgs||AggregateArgsOpt),
Blocks(buildExtractionBlockSet(RN)), NumExitBlocks(~0U) {}
/// definedInRegion - Return true if the specified value is defined in the
/// extracted region.
static bool definedInRegion(const SetVector<BasicBlock *> &Blocks, Value *V) {
if (Instruction *I = dyn_cast<Instruction>(V))
if (Blocks.count(I->getParent()))
return true;
return false;
}
/// definedInCaller - Return true if the specified value is defined in the
/// function being code extracted, but not in the region being extracted.
/// These values must be passed in as live-ins to the function.
static bool definedInCaller(const SetVector<BasicBlock *> &Blocks, Value *V) {
if (isa<Argument>(V)) return true;
if (Instruction *I = dyn_cast<Instruction>(V))
if (!Blocks.count(I->getParent()))
return true;
return false;
}
void CodeExtractor::findInputsOutputs(ValueSet &Inputs,
ValueSet &Outputs) const {
for (SetVector<BasicBlock *>::const_iterator I = Blocks.begin(),
E = Blocks.end();
I != E; ++I) {
BasicBlock *BB = *I;
// If a used value is defined outside the region, it's an input. If an
// instruction is used outside the region, it's an output.
for (BasicBlock::iterator II = BB->begin(), IE = BB->end();
II != IE; ++II) {
for (User::op_iterator OI = II->op_begin(), OE = II->op_end();
OI != OE; ++OI)
if (definedInCaller(Blocks, *OI))
Inputs.insert(*OI);
for (User *U : II->users())
if (!definedInRegion(Blocks, U)) {
Outputs.insert(II);
break;
}
}
}
}
/// severSplitPHINodes - If a PHI node has multiple inputs from outside of the
/// region, we need to split the entry block of the region so that the PHI node
/// is easier to deal with.
void CodeExtractor::severSplitPHINodes(BasicBlock *&Header) {
unsigned NumPredsFromRegion = 0;
unsigned NumPredsOutsideRegion = 0;
if (Header != &Header->getParent()->getEntryBlock()) {
PHINode *PN = dyn_cast<PHINode>(Header->begin());
if (!PN) return; // No PHI nodes.
// If the header node contains any PHI nodes, check to see if there is more
// than one entry from outside the region. If so, we need to sever the
// header block into two.
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
if (Blocks.count(PN->getIncomingBlock(i)))
++NumPredsFromRegion;
else
++NumPredsOutsideRegion;
// If there is one (or fewer) predecessor from outside the region, we don't
// need to do anything special.
if (NumPredsOutsideRegion <= 1) return;
}
// Otherwise, we need to split the header block into two pieces: one
// containing PHI nodes merging values from outside of the region, and a
// second that contains all of the code for the block and merges back any
// incoming values from inside of the region.
BasicBlock::iterator AfterPHIs = Header->getFirstNonPHI();
BasicBlock *NewBB = Header->splitBasicBlock(AfterPHIs,
Header->getName()+".ce");
// We only want to code extract the second block now, and it becomes the new
// header of the region.
BasicBlock *OldPred = Header;
Blocks.remove(OldPred);
Blocks.insert(NewBB);
Header = NewBB;
// Okay, update dominator sets. The blocks that dominate the new one are the
// blocks that dominate TIBB plus the new block itself.
if (DT)
DT->splitBlock(NewBB);
// Okay, now we need to adjust the PHI nodes and any branches from within the
// region to go to the new header block instead of the old header block.
if (NumPredsFromRegion) {
PHINode *PN = cast<PHINode>(OldPred->begin());
// Loop over all of the predecessors of OldPred that are in the region,
// changing them to branch to NewBB instead.
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
if (Blocks.count(PN->getIncomingBlock(i))) {
TerminatorInst *TI = PN->getIncomingBlock(i)->getTerminator();
TI->replaceUsesOfWith(OldPred, NewBB);
}
// Okay, everything within the region is now branching to the right block, we
// just have to update the PHI nodes now, inserting PHI nodes into NewBB.
for (AfterPHIs = OldPred->begin(); isa<PHINode>(AfterPHIs); ++AfterPHIs) {
PHINode *PN = cast<PHINode>(AfterPHIs);
// Create a new PHI node in the new region, which has an incoming value
// from OldPred of PN.
PHINode *NewPN = PHINode::Create(PN->getType(), 1 + NumPredsFromRegion,
PN->getName()+".ce", NewBB->begin());
NewPN->addIncoming(PN, OldPred);
// Loop over all of the incoming value in PN, moving them to NewPN if they
// are from the extracted region.
for (unsigned i = 0; i != PN->getNumIncomingValues(); ++i) {
if (Blocks.count(PN->getIncomingBlock(i))) {
NewPN->addIncoming(PN->getIncomingValue(i), PN->getIncomingBlock(i));
PN->removeIncomingValue(i);
--i;
}
}
}
}
}
void CodeExtractor::splitReturnBlocks() {
for (SetVector<BasicBlock *>::iterator I = Blocks.begin(), E = Blocks.end();
I != E; ++I)
if (ReturnInst *RI = dyn_cast<ReturnInst>((*I)->getTerminator())) {
BasicBlock *New = (*I)->splitBasicBlock(RI, (*I)->getName()+".ret");
if (DT) {
// Old dominates New. New node dominates all other nodes dominated
// by Old.
DomTreeNode *OldNode = DT->getNode(*I);
SmallVector<DomTreeNode*, 8> Children;
for (DomTreeNode::iterator DI = OldNode->begin(), DE = OldNode->end();
DI != DE; ++DI)
Children.push_back(*DI);
DomTreeNode *NewNode = DT->addNewBlock(New, *I);
for (SmallVectorImpl<DomTreeNode *>::iterator I = Children.begin(),
E = Children.end(); I != E; ++I)
DT->changeImmediateDominator(*I, NewNode);
}
}
}
/// constructFunction - make a function based on inputs and outputs, as follows:
/// f(in0, ..., inN, out0, ..., outN)
///
Function *CodeExtractor::constructFunction(const ValueSet &inputs,
const ValueSet &outputs,
BasicBlock *header,
BasicBlock *newRootNode,
BasicBlock *newHeader,
Function *oldFunction,
Module *M) {
DEBUG(dbgs() << "inputs: " << inputs.size() << "\n");
DEBUG(dbgs() << "outputs: " << outputs.size() << "\n");
// This function returns unsigned, outputs will go back by reference.
switch (NumExitBlocks) {
case 0:
case 1: RetTy = Type::getVoidTy(header->getContext()); break;
case 2: RetTy = Type::getInt1Ty(header->getContext()); break;
default: RetTy = Type::getInt16Ty(header->getContext()); break;
}
std::vector<Type*> paramTy;
// Add the types of the input values to the function's argument list
for (ValueSet::const_iterator i = inputs.begin(), e = inputs.end();
i != e; ++i) {
const Value *value = *i;
DEBUG(dbgs() << "value used in func: " << *value << "\n");
paramTy.push_back(value->getType());
}
// Add the types of the output values to the function's argument list.
for (ValueSet::const_iterator I = outputs.begin(), E = outputs.end();
I != E; ++I) {
DEBUG(dbgs() << "instr used in func: " << **I << "\n");
if (AggregateArgs)
paramTy.push_back((*I)->getType());
else
paramTy.push_back(PointerType::getUnqual((*I)->getType()));
}
DEBUG(dbgs() << "Function type: " << *RetTy << " f(");
for (std::vector<Type*>::iterator i = paramTy.begin(),
e = paramTy.end(); i != e; ++i)
DEBUG(dbgs() << **i << ", ");
DEBUG(dbgs() << ")\n");
StructType *StructTy;
if (AggregateArgs && (inputs.size() + outputs.size() > 0)) {
StructTy = StructType::get(M->getContext(), paramTy);
paramTy.clear();
paramTy.push_back(PointerType::getUnqual(StructTy));
}
FunctionType *funcType =
FunctionType::get(RetTy, paramTy, false);
// Create the new function
Function *newFunction = Function::Create(funcType,
GlobalValue::InternalLinkage,
oldFunction->getName() + "_" +
header->getName(), M);
// If the old function is no-throw, so is the new one.
if (oldFunction->doesNotThrow())
newFunction->setDoesNotThrow();
newFunction->getBasicBlockList().push_back(newRootNode);
// Create an iterator to name all of the arguments we inserted.
Function::arg_iterator AI = newFunction->arg_begin();
// Rewrite all users of the inputs in the extracted region to use the
// arguments (or appropriate addressing into struct) instead.
for (unsigned i = 0, e = inputs.size(); i != e; ++i) {
Value *RewriteVal;
if (AggregateArgs) {
Value *Idx[2];
Idx[0] = Constant::getNullValue(Type::getInt32Ty(header->getContext()));
Idx[1] = ConstantInt::get(Type::getInt32Ty(header->getContext()), i);
TerminatorInst *TI = newFunction->begin()->getTerminator();
GetElementPtrInst *GEP = GetElementPtrInst::Create(
StructTy, AI, Idx, "gep_" + inputs[i]->getName(), TI);
RewriteVal = new LoadInst(GEP, "loadgep_" + inputs[i]->getName(), TI);
} else
RewriteVal = AI++;
std::vector<User*> Users(inputs[i]->user_begin(), inputs[i]->user_end());
for (std::vector<User*>::iterator use = Users.begin(), useE = Users.end();
use != useE; ++use)
if (Instruction* inst = dyn_cast<Instruction>(*use))
if (Blocks.count(inst->getParent()))
inst->replaceUsesOfWith(inputs[i], RewriteVal);
}
// Set names for input and output arguments.
if (!AggregateArgs) {
AI = newFunction->arg_begin();
for (unsigned i = 0, e = inputs.size(); i != e; ++i, ++AI)
AI->setName(inputs[i]->getName());
for (unsigned i = 0, e = outputs.size(); i != e; ++i, ++AI)
AI->setName(outputs[i]->getName()+".out");
}
// Rewrite branches to basic blocks outside of the loop to new dummy blocks
// within the new function. This must be done before we lose track of which
// blocks were originally in the code region.
std::vector<User*> Users(header->user_begin(), header->user_end());
for (unsigned i = 0, e = Users.size(); i != e; ++i)
// The BasicBlock which contains the branch is not in the region
// modify the branch target to a new block
if (TerminatorInst *TI = dyn_cast<TerminatorInst>(Users[i]))
if (!Blocks.count(TI->getParent()) &&
TI->getParent()->getParent() == oldFunction)
TI->replaceUsesOfWith(header, newHeader);
return newFunction;
}
/// FindPhiPredForUseInBlock - Given a value and a basic block, find a PHI
/// that uses the value within the basic block, and return the predecessor
/// block associated with that use, or return 0 if none is found.
static BasicBlock* FindPhiPredForUseInBlock(Value* Used, BasicBlock* BB) {
for (Use &U : Used->uses()) {
PHINode *P = dyn_cast<PHINode>(U.getUser());
if (P && P->getParent() == BB)
return P->getIncomingBlock(U);
}
return nullptr;
}
/// emitCallAndSwitchStatement - This method sets up the caller side by adding
/// the call instruction, splitting any PHI nodes in the header block as
/// necessary.
void CodeExtractor::
emitCallAndSwitchStatement(Function *newFunction, BasicBlock *codeReplacer,
ValueSet &inputs, ValueSet &outputs) {
// Emit a call to the new function, passing in: *pointer to struct (if
// aggregating parameters), or plan inputs and allocated memory for outputs
std::vector<Value*> params, StructValues, ReloadOutputs, Reloads;
LLVMContext &Context = newFunction->getContext();
// Add inputs as params, or to be filled into the struct
for (ValueSet::iterator i = inputs.begin(), e = inputs.end(); i != e; ++i)
if (AggregateArgs)
StructValues.push_back(*i);
else
params.push_back(*i);
// Create allocas for the outputs
for (ValueSet::iterator i = outputs.begin(), e = outputs.end(); i != e; ++i) {
if (AggregateArgs) {
StructValues.push_back(*i);
} else {
AllocaInst *alloca =
new AllocaInst((*i)->getType(), nullptr, (*i)->getName()+".loc",
codeReplacer->getParent()->begin()->begin());
ReloadOutputs.push_back(alloca);
params.push_back(alloca);
}
}
StructType *StructArgTy = nullptr;
AllocaInst *Struct = nullptr;
if (AggregateArgs && (inputs.size() + outputs.size() > 0)) {
std::vector<Type*> ArgTypes;
for (ValueSet::iterator v = StructValues.begin(),
ve = StructValues.end(); v != ve; ++v)
ArgTypes.push_back((*v)->getType());
// Allocate a struct at the beginning of this function
StructArgTy = StructType::get(newFunction->getContext(), ArgTypes);
Struct =
new AllocaInst(StructArgTy, nullptr, "structArg",
codeReplacer->getParent()->begin()->begin());
params.push_back(Struct);
for (unsigned i = 0, e = inputs.size(); i != e; ++i) {
Value *Idx[2];
Idx[0] = Constant::getNullValue(Type::getInt32Ty(Context));
Idx[1] = ConstantInt::get(Type::getInt32Ty(Context), i);
GetElementPtrInst *GEP = GetElementPtrInst::Create(
StructArgTy, Struct, Idx, "gep_" + StructValues[i]->getName());
codeReplacer->getInstList().push_back(GEP);
StoreInst *SI = new StoreInst(StructValues[i], GEP);
codeReplacer->getInstList().push_back(SI);
}
}
// Emit the call to the function
CallInst *call = CallInst::Create(newFunction, params,
NumExitBlocks > 1 ? "targetBlock" : "");
codeReplacer->getInstList().push_back(call);
Function::arg_iterator OutputArgBegin = newFunction->arg_begin();
unsigned FirstOut = inputs.size();
if (!AggregateArgs)
std::advance(OutputArgBegin, inputs.size());
// Reload the outputs passed in by reference
for (unsigned i = 0, e = outputs.size(); i != e; ++i) {
Value *Output = nullptr;
if (AggregateArgs) {
Value *Idx[2];
Idx[0] = Constant::getNullValue(Type::getInt32Ty(Context));
Idx[1] = ConstantInt::get(Type::getInt32Ty(Context), FirstOut + i);
GetElementPtrInst *GEP = GetElementPtrInst::Create(
StructArgTy, Struct, Idx, "gep_reload_" + outputs[i]->getName());
codeReplacer->getInstList().push_back(GEP);
Output = GEP;
} else {
Output = ReloadOutputs[i];
}
LoadInst *load = new LoadInst(Output, outputs[i]->getName()+".reload");
Reloads.push_back(load);
codeReplacer->getInstList().push_back(load);
std::vector<User*> Users(outputs[i]->user_begin(), outputs[i]->user_end());
for (unsigned u = 0, e = Users.size(); u != e; ++u) {
Instruction *inst = cast<Instruction>(Users[u]);
if (!Blocks.count(inst->getParent()))
inst->replaceUsesOfWith(outputs[i], load);
}
}
// Now we can emit a switch statement using the call as a value.
SwitchInst *TheSwitch =
SwitchInst::Create(Constant::getNullValue(Type::getInt16Ty(Context)),
codeReplacer, 0, codeReplacer);
// Since there may be multiple exits from the original region, make the new
// function return an unsigned, switch on that number. This loop iterates
// over all of the blocks in the extracted region, updating any terminator
// instructions in the to-be-extracted region that branch to blocks that are
// not in the region to be extracted.
std::map<BasicBlock*, BasicBlock*> ExitBlockMap;
unsigned switchVal = 0;
for (SetVector<BasicBlock*>::const_iterator i = Blocks.begin(),
e = Blocks.end(); i != e; ++i) {
TerminatorInst *TI = (*i)->getTerminator();
for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
if (!Blocks.count(TI->getSuccessor(i))) {
BasicBlock *OldTarget = TI->getSuccessor(i);
// add a new basic block which returns the appropriate value
BasicBlock *&NewTarget = ExitBlockMap[OldTarget];
if (!NewTarget) {
// If we don't already have an exit stub for this non-extracted
// destination, create one now!
NewTarget = BasicBlock::Create(Context,
OldTarget->getName() + ".exitStub",
newFunction);
unsigned SuccNum = switchVal++;
Value *brVal = nullptr;
switch (NumExitBlocks) {
case 0:
case 1: break; // No value needed.
case 2: // Conditional branch, return a bool
brVal = ConstantInt::get(Type::getInt1Ty(Context), !SuccNum);
break;
default:
brVal = ConstantInt::get(Type::getInt16Ty(Context), SuccNum);
break;
}
ReturnInst *NTRet = ReturnInst::Create(Context, brVal, NewTarget);
// Update the switch instruction.
TheSwitch->addCase(ConstantInt::get(Type::getInt16Ty(Context),
SuccNum),
OldTarget);
// Restore values just before we exit
Function::arg_iterator OAI = OutputArgBegin;
for (unsigned out = 0, e = outputs.size(); out != e; ++out) {
// For an invoke, the normal destination is the only one that is
// dominated by the result of the invocation
BasicBlock *DefBlock = cast<Instruction>(outputs[out])->getParent();
bool DominatesDef = true;
if (InvokeInst *Invoke = dyn_cast<InvokeInst>(outputs[out])) {
DefBlock = Invoke->getNormalDest();
// Make sure we are looking at the original successor block, not
// at a newly inserted exit block, which won't be in the dominator
// info.
for (std::map<BasicBlock*, BasicBlock*>::iterator I =
ExitBlockMap.begin(), E = ExitBlockMap.end(); I != E; ++I)
if (DefBlock == I->second) {
DefBlock = I->first;
break;
}
// In the extract block case, if the block we are extracting ends
// with an invoke instruction, make sure that we don't emit a
// store of the invoke value for the unwind block.
if (!DT && DefBlock != OldTarget)
DominatesDef = false;
}
if (DT) {
DominatesDef = DT->dominates(DefBlock, OldTarget);
// If the output value is used by a phi in the target block,
// then we need to test for dominance of the phi's predecessor
// instead. Unfortunately, this a little complicated since we
// have already rewritten uses of the value to uses of the reload.
BasicBlock* pred = FindPhiPredForUseInBlock(Reloads[out],
OldTarget);
if (pred && DT && DT->dominates(DefBlock, pred))
DominatesDef = true;
}
if (DominatesDef) {
if (AggregateArgs) {
Value *Idx[2];
Idx[0] = Constant::getNullValue(Type::getInt32Ty(Context));
Idx[1] = ConstantInt::get(Type::getInt32Ty(Context),
FirstOut+out);
GetElementPtrInst *GEP = GetElementPtrInst::Create(
StructArgTy, OAI, Idx, "gep_" + outputs[out]->getName(),
NTRet);
new StoreInst(outputs[out], GEP, NTRet);
} else {
new StoreInst(outputs[out], OAI, NTRet);
}
}
// Advance output iterator even if we don't emit a store
if (!AggregateArgs) ++OAI;
}
}
// rewrite the original branch instruction with this new target
TI->setSuccessor(i, NewTarget);
}
}
// Now that we've done the deed, simplify the switch instruction.
Type *OldFnRetTy = TheSwitch->getParent()->getParent()->getReturnType();
switch (NumExitBlocks) {
case 0:
// There are no successors (the block containing the switch itself), which
// means that previously this was the last part of the function, and hence
// this should be rewritten as a `ret'
// Check if the function should return a value
if (OldFnRetTy->isVoidTy()) {
ReturnInst::Create(Context, nullptr, TheSwitch); // Return void
} else if (OldFnRetTy == TheSwitch->getCondition()->getType()) {
// return what we have
ReturnInst::Create(Context, TheSwitch->getCondition(), TheSwitch);
} else {
// Otherwise we must have code extracted an unwind or something, just
// return whatever we want.
ReturnInst::Create(Context,
Constant::getNullValue(OldFnRetTy), TheSwitch);
}
TheSwitch->eraseFromParent();
break;
case 1:
// Only a single destination, change the switch into an unconditional
// branch.
BranchInst::Create(TheSwitch->getSuccessor(1), TheSwitch);
TheSwitch->eraseFromParent();
break;
case 2:
BranchInst::Create(TheSwitch->getSuccessor(1), TheSwitch->getSuccessor(2),
call, TheSwitch);
TheSwitch->eraseFromParent();
break;
default:
// Otherwise, make the default destination of the switch instruction be one
// of the other successors.
TheSwitch->setCondition(call);
TheSwitch->setDefaultDest(TheSwitch->getSuccessor(NumExitBlocks));
// Remove redundant case
TheSwitch->removeCase(SwitchInst::CaseIt(TheSwitch, NumExitBlocks-1));
break;
}
}
void CodeExtractor::moveCodeToFunction(Function *newFunction) {
Function *oldFunc = (*Blocks.begin())->getParent();
Function::BasicBlockListType &oldBlocks = oldFunc->getBasicBlockList();
Function::BasicBlockListType &newBlocks = newFunction->getBasicBlockList();
for (SetVector<BasicBlock*>::const_iterator i = Blocks.begin(),
e = Blocks.end(); i != e; ++i) {
// Delete the basic block from the old function, and the list of blocks
oldBlocks.remove(*i);
// Insert this basic block into the new function
newBlocks.push_back(*i);
}
}
Function *CodeExtractor::extractCodeRegion() {
if (!isEligible())
return nullptr;
ValueSet inputs, outputs;
// Assumption: this is a single-entry code region, and the header is the first
// block in the region.
BasicBlock *header = *Blocks.begin();
// If we have to split PHI nodes or the entry block, do so now.
severSplitPHINodes(header);
// If we have any return instructions in the region, split those blocks so
// that the return is not in the region.
splitReturnBlocks();
Function *oldFunction = header->getParent();
// This takes place of the original loop
BasicBlock *codeReplacer = BasicBlock::Create(header->getContext(),
"codeRepl", oldFunction,
header);
// The new function needs a root node because other nodes can branch to the
// head of the region, but the entry node of a function cannot have preds.
BasicBlock *newFuncRoot = BasicBlock::Create(header->getContext(),
"newFuncRoot");
newFuncRoot->getInstList().push_back(BranchInst::Create(header));
// Find inputs to, outputs from the code region.
findInputsOutputs(inputs, outputs);
SmallPtrSet<BasicBlock *, 1> ExitBlocks;
for (SetVector<BasicBlock *>::iterator I = Blocks.begin(), E = Blocks.end();
I != E; ++I)
for (succ_iterator SI = succ_begin(*I), SE = succ_end(*I); SI != SE; ++SI)
if (!Blocks.count(*SI))
ExitBlocks.insert(*SI);
NumExitBlocks = ExitBlocks.size();
// Construct new function based on inputs/outputs & add allocas for all defs.
Function *newFunction = constructFunction(inputs, outputs, header,
newFuncRoot,
codeReplacer, oldFunction,
oldFunction->getParent());
emitCallAndSwitchStatement(newFunction, codeReplacer, inputs, outputs);
moveCodeToFunction(newFunction);
// Loop over all of the PHI nodes in the header block, and change any
// references to the old incoming edge to be the new incoming edge.
for (BasicBlock::iterator I = header->begin(); isa<PHINode>(I); ++I) {
PHINode *PN = cast<PHINode>(I);
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
if (!Blocks.count(PN->getIncomingBlock(i)))
PN->setIncomingBlock(i, newFuncRoot);
}
// Look at all successors of the codeReplacer block. If any of these blocks
// had PHI nodes in them, we need to update the "from" block to be the code
// replacer, not the original block in the extracted region.
std::vector<BasicBlock*> Succs(succ_begin(codeReplacer),
succ_end(codeReplacer));
for (unsigned i = 0, e = Succs.size(); i != e; ++i)
for (BasicBlock::iterator I = Succs[i]->begin(); isa<PHINode>(I); ++I) {
PHINode *PN = cast<PHINode>(I);
std::set<BasicBlock*> ProcessedPreds;
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
if (Blocks.count(PN->getIncomingBlock(i))) {
if (ProcessedPreds.insert(PN->getIncomingBlock(i)).second)
PN->setIncomingBlock(i, codeReplacer);
else {
// There were multiple entries in the PHI for this block, now there
// is only one, so remove the duplicated entries.
PN->removeIncomingValue(i, false);
--i; --e;
}
}
}
//cerr << "NEW FUNCTION: " << *newFunction;
// verifyFunction(*newFunction);
// cerr << "OLD FUNCTION: " << *oldFunction;
// verifyFunction(*oldFunction);
DEBUG(if (verifyFunction(*newFunction))
report_fatal_error("verifyFunction failed!"));
return newFunction;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/SSAUpdater.cpp | //===- SSAUpdater.cpp - Unstructured SSA Update Tool ----------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the SSAUpdater class.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/SSAUpdater.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/TinyPtrVector.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/SSAUpdaterImpl.h"
using namespace llvm;
#define DEBUG_TYPE "ssaupdater"
typedef DenseMap<BasicBlock*, Value*> AvailableValsTy;
static AvailableValsTy &getAvailableVals(void *AV) {
return *static_cast<AvailableValsTy*>(AV);
}
SSAUpdater::SSAUpdater(SmallVectorImpl<PHINode*> *NewPHI)
: AV(nullptr), ProtoType(nullptr), ProtoName(), InsertedPHIs(NewPHI) {}
SSAUpdater::~SSAUpdater() {
delete static_cast<AvailableValsTy*>(AV);
}
void SSAUpdater::Initialize(Type *Ty, StringRef Name) {
if (!AV)
AV = new AvailableValsTy();
else
getAvailableVals(AV).clear();
ProtoType = Ty;
ProtoName = Name;
}
bool SSAUpdater::HasValueForBlock(BasicBlock *BB) const {
return getAvailableVals(AV).count(BB);
}
void SSAUpdater::AddAvailableValue(BasicBlock *BB, Value *V) {
assert(ProtoType && "Need to initialize SSAUpdater");
assert(ProtoType == V->getType() &&
"All rewritten values must have the same type");
getAvailableVals(AV)[BB] = V;
}
static bool IsEquivalentPHI(PHINode *PHI,
SmallDenseMap<BasicBlock*, Value*, 8> &ValueMapping) {
unsigned PHINumValues = PHI->getNumIncomingValues();
if (PHINumValues != ValueMapping.size())
return false;
// Scan the phi to see if it matches.
for (unsigned i = 0, e = PHINumValues; i != e; ++i)
if (ValueMapping[PHI->getIncomingBlock(i)] !=
PHI->getIncomingValue(i)) {
return false;
}
return true;
}
Value *SSAUpdater::GetValueAtEndOfBlock(BasicBlock *BB) {
Value *Res = GetValueAtEndOfBlockInternal(BB);
return Res;
}
Value *SSAUpdater::GetValueInMiddleOfBlock(BasicBlock *BB) {
// If there is no definition of the renamed variable in this block, just use
// GetValueAtEndOfBlock to do our work.
if (!HasValueForBlock(BB))
return GetValueAtEndOfBlock(BB);
// Otherwise, we have the hard case. Get the live-in values for each
// predecessor.
SmallVector<std::pair<BasicBlock*, Value*>, 8> PredValues;
Value *SingularValue = nullptr;
// We can get our predecessor info by walking the pred_iterator list, but it
// is relatively slow. If we already have PHI nodes in this block, walk one
// of them to get the predecessor list instead.
if (PHINode *SomePhi = dyn_cast<PHINode>(BB->begin())) {
for (unsigned i = 0, e = SomePhi->getNumIncomingValues(); i != e; ++i) {
BasicBlock *PredBB = SomePhi->getIncomingBlock(i);
Value *PredVal = GetValueAtEndOfBlock(PredBB);
PredValues.push_back(std::make_pair(PredBB, PredVal));
// Compute SingularValue.
if (i == 0)
SingularValue = PredVal;
else if (PredVal != SingularValue)
SingularValue = nullptr;
}
} else {
bool isFirstPred = true;
for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) {
BasicBlock *PredBB = *PI;
Value *PredVal = GetValueAtEndOfBlock(PredBB);
PredValues.push_back(std::make_pair(PredBB, PredVal));
// Compute SingularValue.
if (isFirstPred) {
SingularValue = PredVal;
isFirstPred = false;
} else if (PredVal != SingularValue)
SingularValue = nullptr;
}
}
// If there are no predecessors, just return undef.
if (PredValues.empty())
return UndefValue::get(ProtoType);
// Otherwise, if all the merged values are the same, just use it.
if (SingularValue)
return SingularValue;
// Otherwise, we do need a PHI: check to see if we already have one available
// in this block that produces the right value.
if (isa<PHINode>(BB->begin())) {
SmallDenseMap<BasicBlock*, Value*, 8> ValueMapping(PredValues.begin(),
PredValues.end());
PHINode *SomePHI;
for (BasicBlock::iterator It = BB->begin();
(SomePHI = dyn_cast<PHINode>(It)); ++It) {
if (IsEquivalentPHI(SomePHI, ValueMapping))
return SomePHI;
}
}
// Ok, we have no way out, insert a new one now.
PHINode *InsertedPHI = PHINode::Create(ProtoType, PredValues.size(),
ProtoName, &BB->front());
// Fill in all the predecessors of the PHI.
for (const auto &PredValue : PredValues)
InsertedPHI->addIncoming(PredValue.second, PredValue.first);
// See if the PHI node can be merged to a single value. This can happen in
// loop cases when we get a PHI of itself and one other value.
if (Value *V =
SimplifyInstruction(InsertedPHI, BB->getModule()->getDataLayout())) {
InsertedPHI->eraseFromParent();
return V;
}
// Set the DebugLoc of the inserted PHI, if available.
DebugLoc DL;
if (const Instruction *I = BB->getFirstNonPHI())
DL = I->getDebugLoc();
InsertedPHI->setDebugLoc(DL);
// If the client wants to know about all new instructions, tell it.
if (InsertedPHIs) InsertedPHIs->push_back(InsertedPHI);
DEBUG(dbgs() << " Inserted PHI: " << *InsertedPHI << "\n");
return InsertedPHI;
}
void SSAUpdater::RewriteUse(Use &U) {
Instruction *User = cast<Instruction>(U.getUser());
Value *V;
if (PHINode *UserPN = dyn_cast<PHINode>(User))
V = GetValueAtEndOfBlock(UserPN->getIncomingBlock(U));
else
V = GetValueInMiddleOfBlock(User->getParent());
// Notify that users of the existing value that it is being replaced.
Value *OldVal = U.get();
if (OldVal != V && OldVal->hasValueHandle())
ValueHandleBase::ValueIsRAUWd(OldVal, V);
U.set(V);
}
void SSAUpdater::RewriteUseAfterInsertions(Use &U) {
Instruction *User = cast<Instruction>(U.getUser());
Value *V;
if (PHINode *UserPN = dyn_cast<PHINode>(User))
V = GetValueAtEndOfBlock(UserPN->getIncomingBlock(U));
else
V = GetValueAtEndOfBlock(User->getParent());
U.set(V);
}
namespace llvm {
template<>
class SSAUpdaterTraits<SSAUpdater> {
public:
typedef BasicBlock BlkT;
typedef Value *ValT;
typedef PHINode PhiT;
typedef succ_iterator BlkSucc_iterator;
static BlkSucc_iterator BlkSucc_begin(BlkT *BB) { return succ_begin(BB); }
static BlkSucc_iterator BlkSucc_end(BlkT *BB) { return succ_end(BB); }
class PHI_iterator {
private:
PHINode *PHI;
unsigned idx;
public:
explicit PHI_iterator(PHINode *P) // begin iterator
: PHI(P), idx(0) {}
PHI_iterator(PHINode *P, bool) // end iterator
: PHI(P), idx(PHI->getNumIncomingValues()) {}
PHI_iterator &operator++() { ++idx; return *this; }
bool operator==(const PHI_iterator& x) const { return idx == x.idx; }
bool operator!=(const PHI_iterator& x) const { return !operator==(x); }
Value *getIncomingValue() { return PHI->getIncomingValue(idx); }
BasicBlock *getIncomingBlock() { return PHI->getIncomingBlock(idx); }
};
static PHI_iterator PHI_begin(PhiT *PHI) { return PHI_iterator(PHI); }
static PHI_iterator PHI_end(PhiT *PHI) {
return PHI_iterator(PHI, true);
}
/// FindPredecessorBlocks - Put the predecessors of Info->BB into the Preds
/// vector, set Info->NumPreds, and allocate space in Info->Preds.
static void FindPredecessorBlocks(BasicBlock *BB,
SmallVectorImpl<BasicBlock*> *Preds) {
// We can get our predecessor info by walking the pred_iterator list,
// but it is relatively slow. If we already have PHI nodes in this
// block, walk one of them to get the predecessor list instead.
if (PHINode *SomePhi = dyn_cast<PHINode>(BB->begin())) {
Preds->append(SomePhi->block_begin(), SomePhi->block_end());
} else {
for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI)
Preds->push_back(*PI);
}
}
/// GetUndefVal - Get an undefined value of the same type as the value
/// being handled.
static Value *GetUndefVal(BasicBlock *BB, SSAUpdater *Updater) {
return UndefValue::get(Updater->ProtoType);
}
/// CreateEmptyPHI - Create a new PHI instruction in the specified block.
/// Reserve space for the operands but do not fill them in yet.
static Value *CreateEmptyPHI(BasicBlock *BB, unsigned NumPreds,
SSAUpdater *Updater) {
PHINode *PHI = PHINode::Create(Updater->ProtoType, NumPreds,
Updater->ProtoName, &BB->front());
return PHI;
}
/// AddPHIOperand - Add the specified value as an operand of the PHI for
/// the specified predecessor block.
static void AddPHIOperand(PHINode *PHI, Value *Val, BasicBlock *Pred) {
PHI->addIncoming(Val, Pred);
}
/// InstrIsPHI - Check if an instruction is a PHI.
///
static PHINode *InstrIsPHI(Instruction *I) {
return dyn_cast<PHINode>(I);
}
/// ValueIsPHI - Check if a value is a PHI.
///
static PHINode *ValueIsPHI(Value *Val, SSAUpdater *Updater) {
return dyn_cast<PHINode>(Val);
}
/// ValueIsNewPHI - Like ValueIsPHI but also check if the PHI has no source
/// operands, i.e., it was just added.
static PHINode *ValueIsNewPHI(Value *Val, SSAUpdater *Updater) {
PHINode *PHI = ValueIsPHI(Val, Updater);
if (PHI && PHI->getNumIncomingValues() == 0)
return PHI;
return nullptr;
}
/// GetPHIValue - For the specified PHI instruction, return the value
/// that it defines.
static Value *GetPHIValue(PHINode *PHI) {
return PHI;
}
};
} // End llvm namespace
/// Check to see if AvailableVals has an entry for the specified BB and if so,
/// return it. If not, construct SSA form by first calculating the required
/// placement of PHIs and then inserting new PHIs where needed.
Value *SSAUpdater::GetValueAtEndOfBlockInternal(BasicBlock *BB) {
AvailableValsTy &AvailableVals = getAvailableVals(AV);
if (Value *V = AvailableVals[BB])
return V;
SSAUpdaterImpl<SSAUpdater> Impl(this, &AvailableVals, InsertedPHIs);
return Impl.GetValue(BB);
}
//===----------------------------------------------------------------------===//
// LoadAndStorePromoter Implementation
//===----------------------------------------------------------------------===//
LoadAndStorePromoter::
LoadAndStorePromoter(ArrayRef<const Instruction*> Insts,
SSAUpdater &S, StringRef BaseName) : SSA(S) {
if (Insts.empty()) return;
const Value *SomeVal;
if (const LoadInst *LI = dyn_cast<LoadInst>(Insts[0]))
SomeVal = LI;
else
SomeVal = cast<StoreInst>(Insts[0])->getOperand(0);
if (BaseName.empty())
BaseName = SomeVal->getName();
SSA.Initialize(SomeVal->getType(), BaseName);
}
void LoadAndStorePromoter::
run(const SmallVectorImpl<Instruction*> &Insts) const {
// First step: bucket up uses of the alloca by the block they occur in.
// This is important because we have to handle multiple defs/uses in a block
// ourselves: SSAUpdater is purely for cross-block references.
DenseMap<BasicBlock*, TinyPtrVector<Instruction*> > UsesByBlock;
for (Instruction *User : Insts)
UsesByBlock[User->getParent()].push_back(User);
// Okay, now we can iterate over all the blocks in the function with uses,
// processing them. Keep track of which loads are loading a live-in value.
// Walk the uses in the use-list order to be determinstic.
SmallVector<LoadInst*, 32> LiveInLoads;
DenseMap<Value*, Value*> ReplacedLoads;
for (Instruction *User : Insts) {
BasicBlock *BB = User->getParent();
TinyPtrVector<Instruction*> &BlockUses = UsesByBlock[BB];
// If this block has already been processed, ignore this repeat use.
if (BlockUses.empty()) continue;
// Okay, this is the first use in the block. If this block just has a
// single user in it, we can rewrite it trivially.
if (BlockUses.size() == 1) {
// If it is a store, it is a trivial def of the value in the block.
if (StoreInst *SI = dyn_cast<StoreInst>(User)) {
updateDebugInfo(SI);
SSA.AddAvailableValue(BB, SI->getOperand(0));
} else
// Otherwise it is a load, queue it to rewrite as a live-in load.
LiveInLoads.push_back(cast<LoadInst>(User));
BlockUses.clear();
continue;
}
// Otherwise, check to see if this block is all loads.
bool HasStore = false;
for (Instruction *I : BlockUses) {
if (isa<StoreInst>(I)) {
HasStore = true;
break;
}
}
// If so, we can queue them all as live in loads. We don't have an
// efficient way to tell which on is first in the block and don't want to
// scan large blocks, so just add all loads as live ins.
if (!HasStore) {
for (Instruction *I : BlockUses)
LiveInLoads.push_back(cast<LoadInst>(I));
BlockUses.clear();
continue;
}
// Otherwise, we have mixed loads and stores (or just a bunch of stores).
// Since SSAUpdater is purely for cross-block values, we need to determine
// the order of these instructions in the block. If the first use in the
// block is a load, then it uses the live in value. The last store defines
// the live out value. We handle this by doing a linear scan of the block.
Value *StoredValue = nullptr;
for (Instruction &I : *BB) {
if (LoadInst *L = dyn_cast<LoadInst>(&I)) {
// If this is a load from an unrelated pointer, ignore it.
if (!isInstInList(L, Insts)) continue;
// If we haven't seen a store yet, this is a live in use, otherwise
// use the stored value.
if (StoredValue) {
replaceLoadWithValue(L, StoredValue);
L->replaceAllUsesWith(StoredValue);
ReplacedLoads[L] = StoredValue;
} else {
LiveInLoads.push_back(L);
}
continue;
}
if (StoreInst *SI = dyn_cast<StoreInst>(&I)) {
// If this is a store to an unrelated pointer, ignore it.
if (!isInstInList(SI, Insts)) continue;
updateDebugInfo(SI);
// Remember that this is the active value in the block.
StoredValue = SI->getOperand(0);
}
}
// The last stored value that happened is the live-out for the block.
assert(StoredValue && "Already checked that there is a store in block");
SSA.AddAvailableValue(BB, StoredValue);
BlockUses.clear();
}
// Okay, now we rewrite all loads that use live-in values in the loop,
// inserting PHI nodes as necessary.
for (LoadInst *ALoad : LiveInLoads) {
Value *NewVal = SSA.GetValueInMiddleOfBlock(ALoad->getParent());
replaceLoadWithValue(ALoad, NewVal);
// Avoid assertions in unreachable code.
if (NewVal == ALoad) NewVal = UndefValue::get(NewVal->getType());
ALoad->replaceAllUsesWith(NewVal);
ReplacedLoads[ALoad] = NewVal;
}
// Allow the client to do stuff before we start nuking things.
doExtraRewritesBeforeFinalDeletion();
// Now that everything is rewritten, delete the old instructions from the
// function. They should all be dead now.
for (Instruction *User : Insts) {
// If this is a load that still has uses, then the load must have been added
// as a live value in the SSAUpdate data structure for a block (e.g. because
// the loaded value was stored later). In this case, we need to recursively
// propagate the updates until we get to the real value.
if (!User->use_empty()) {
Value *NewVal = ReplacedLoads[User];
assert(NewVal && "not a replaced load?");
// Propagate down to the ultimate replacee. The intermediately loads
// could theoretically already have been deleted, so we don't want to
// dereference the Value*'s.
DenseMap<Value*, Value*>::iterator RLI = ReplacedLoads.find(NewVal);
while (RLI != ReplacedLoads.end()) {
NewVal = RLI->second;
RLI = ReplacedLoads.find(NewVal);
}
replaceLoadWithValue(cast<LoadInst>(User), NewVal);
User->replaceAllUsesWith(NewVal);
}
instructionDeleted(User);
User->eraseFromParent();
}
}
bool
LoadAndStorePromoter::isInstInList(Instruction *I,
const SmallVectorImpl<Instruction*> &Insts)
const {
return std::find(Insts.begin(), Insts.end(), I) != Insts.end();
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/BasicBlockUtils.cpp | //===-- BasicBlockUtils.cpp - BasicBlock Utilities -------------------------==//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This family of functions perform manipulations on basic blocks, and
// instructions contained within basic blocks.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/CFG.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/MemoryDependenceAnalysis.h"
#include "llvm/IR/Constant.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/Local.h"
#include <algorithm>
using namespace llvm;
/// DeleteDeadBlock - Delete the specified block, which must have no
/// predecessors.
void llvm::DeleteDeadBlock(BasicBlock *BB) {
assert((pred_begin(BB) == pred_end(BB) ||
// Can delete self loop.
BB->getSinglePredecessor() == BB) && "Block is not dead!");
TerminatorInst *BBTerm = BB->getTerminator();
// Loop through all of our successors and make sure they know that one
// of their predecessors is going away.
for (unsigned i = 0, e = BBTerm->getNumSuccessors(); i != e; ++i)
BBTerm->getSuccessor(i)->removePredecessor(BB);
// Zap all the instructions in the block.
while (!BB->empty()) {
Instruction &I = BB->back();
// If this instruction is used, replace uses with an arbitrary value.
// Because control flow can't get here, we don't care what we replace the
// value with. Note that since this block is unreachable, and all values
// contained within it must dominate their uses, that all uses will
// eventually be removed (they are themselves dead).
if (!I.use_empty())
I.replaceAllUsesWith(UndefValue::get(I.getType()));
BB->getInstList().pop_back();
}
// Zap the block!
BB->eraseFromParent();
}
/// FoldSingleEntryPHINodes - We know that BB has one predecessor. If there are
/// any single-entry PHI nodes in it, fold them away. This handles the case
/// when all entries to the PHI nodes in a block are guaranteed equal, such as
/// when the block has exactly one predecessor.
void llvm::FoldSingleEntryPHINodes(BasicBlock *BB, AliasAnalysis *AA,
MemoryDependenceAnalysis *MemDep) {
if (!isa<PHINode>(BB->begin())) return;
while (PHINode *PN = dyn_cast<PHINode>(BB->begin())) {
if (PN->getIncomingValue(0) != PN)
PN->replaceAllUsesWith(PN->getIncomingValue(0));
else
PN->replaceAllUsesWith(UndefValue::get(PN->getType()));
if (MemDep)
MemDep->removeInstruction(PN); // Memdep updates AA itself.
else if (AA && isa<PointerType>(PN->getType()))
AA->deleteValue(PN);
PN->eraseFromParent();
}
}
/// DeleteDeadPHIs - Examine each PHI in the given block and delete it if it
/// is dead. Also recursively delete any operands that become dead as
/// a result. This includes tracing the def-use list from the PHI to see if
/// it is ultimately unused or if it reaches an unused cycle.
bool llvm::DeleteDeadPHIs(BasicBlock *BB, const TargetLibraryInfo *TLI) {
// Recursively deleting a PHI may cause multiple PHIs to be deleted
// or RAUW'd undef, so use an array of WeakTrackingVH for the PHIs to delete.
SmallVector<WeakTrackingVH, 8> PHIs;
for (BasicBlock::iterator I = BB->begin();
PHINode *PN = dyn_cast<PHINode>(I); ++I)
PHIs.push_back(PN);
bool Changed = false;
for (unsigned i = 0, e = PHIs.size(); i != e; ++i)
if (PHINode *PN = dyn_cast_or_null<PHINode>(PHIs[i].operator Value*()))
Changed |= RecursivelyDeleteDeadPHINode(PN, TLI);
return Changed;
}
/// MergeBlockIntoPredecessor - Attempts to merge a block into its predecessor,
/// if possible. The return value indicates success or failure.
bool llvm::MergeBlockIntoPredecessor(BasicBlock *BB, DominatorTree *DT,
LoopInfo *LI, AliasAnalysis *AA,
MemoryDependenceAnalysis *MemDep) {
// Don't merge away blocks who have their address taken.
if (BB->hasAddressTaken()) return false;
// Can't merge if there are multiple predecessors, or no predecessors.
BasicBlock *PredBB = BB->getUniquePredecessor();
if (!PredBB) return false;
// Don't break self-loops.
if (PredBB == BB) return false;
// Don't break invokes.
if (isa<InvokeInst>(PredBB->getTerminator())) return false;
succ_iterator SI(succ_begin(PredBB)), SE(succ_end(PredBB));
BasicBlock *OnlySucc = BB;
for (; SI != SE; ++SI)
if (*SI != OnlySucc) {
OnlySucc = nullptr; // There are multiple distinct successors!
break;
}
// Can't merge if there are multiple successors.
if (!OnlySucc) return false;
// Can't merge if there is PHI loop.
for (BasicBlock::iterator BI = BB->begin(), BE = BB->end(); BI != BE; ++BI) {
if (PHINode *PN = dyn_cast<PHINode>(BI)) {
for (Value *IncValue : PN->incoming_values())
if (IncValue == PN)
return false;
} else
break;
}
// Begin by getting rid of unneeded PHIs.
if (isa<PHINode>(BB->front()))
FoldSingleEntryPHINodes(BB, AA, MemDep);
// Delete the unconditional branch from the predecessor...
PredBB->getInstList().pop_back();
// Make all PHI nodes that referred to BB now refer to Pred as their
// source...
BB->replaceAllUsesWith(PredBB);
// Move all definitions in the successor to the predecessor...
PredBB->getInstList().splice(PredBB->end(), BB->getInstList());
// Inherit predecessors name if it exists.
if (!PredBB->hasName())
PredBB->takeName(BB);
// Finally, erase the old block and update dominator info.
if (DT)
if (DomTreeNode *DTN = DT->getNode(BB)) {
DomTreeNode *PredDTN = DT->getNode(PredBB);
SmallVector<DomTreeNode *, 8> Children(DTN->begin(), DTN->end());
for (SmallVectorImpl<DomTreeNode *>::iterator DI = Children.begin(),
DE = Children.end();
DI != DE; ++DI)
DT->changeImmediateDominator(*DI, PredDTN);
DT->eraseNode(BB);
}
if (LI)
LI->removeBlock(BB);
if (MemDep)
MemDep->invalidateCachedPredecessors();
BB->eraseFromParent();
return true;
}
/// ReplaceInstWithValue - Replace all uses of an instruction (specified by BI)
/// with a value, then remove and delete the original instruction.
///
void llvm::ReplaceInstWithValue(BasicBlock::InstListType &BIL,
BasicBlock::iterator &BI, Value *V) {
Instruction &I = *BI;
// Replaces all of the uses of the instruction with uses of the value
I.replaceAllUsesWith(V);
// Make sure to propagate a name if there is one already.
if (I.hasName() && !V->hasName())
V->takeName(&I);
// Delete the unnecessary instruction now...
BI = BIL.erase(BI);
}
/// ReplaceInstWithInst - Replace the instruction specified by BI with the
/// instruction specified by I. The original instruction is deleted and BI is
/// updated to point to the new instruction.
///
void llvm::ReplaceInstWithInst(BasicBlock::InstListType &BIL,
BasicBlock::iterator &BI, Instruction *I) {
assert(I->getParent() == nullptr &&
"ReplaceInstWithInst: Instruction already inserted into basic block!");
// Copy debug location to newly added instruction, if it wasn't already set
// by the caller.
if (!I->getDebugLoc())
I->setDebugLoc(BI->getDebugLoc());
// Insert the new instruction into the basic block...
BasicBlock::iterator New = BIL.insert(BI, I);
// Replace all uses of the old instruction, and delete it.
ReplaceInstWithValue(BIL, BI, I);
// Move BI back to point to the newly inserted instruction
BI = New;
}
/// ReplaceInstWithInst - Replace the instruction specified by From with the
/// instruction specified by To.
///
void llvm::ReplaceInstWithInst(Instruction *From, Instruction *To) {
BasicBlock::iterator BI(From);
ReplaceInstWithInst(From->getParent()->getInstList(), BI, To);
}
/// SplitEdge - Split the edge connecting specified block. Pass P must
/// not be NULL.
BasicBlock *llvm::SplitEdge(BasicBlock *BB, BasicBlock *Succ, DominatorTree *DT,
LoopInfo *LI) {
unsigned SuccNum = GetSuccessorNumber(BB, Succ);
// If this is a critical edge, let SplitCriticalEdge do it.
TerminatorInst *LatchTerm = BB->getTerminator();
if (SplitCriticalEdge(LatchTerm, SuccNum, CriticalEdgeSplittingOptions(DT, LI)
.setPreserveLCSSA()))
return LatchTerm->getSuccessor(SuccNum);
// If the edge isn't critical, then BB has a single successor or Succ has a
// single pred. Split the block.
if (BasicBlock *SP = Succ->getSinglePredecessor()) {
// If the successor only has a single pred, split the top of the successor
// block.
assert(SP == BB && "CFG broken");
SP = nullptr;
return SplitBlock(Succ, Succ->begin(), DT, LI);
}
// Otherwise, if BB has a single successor, split it at the bottom of the
// block.
assert(BB->getTerminator()->getNumSuccessors() == 1 &&
"Should have a single succ!");
return SplitBlock(BB, BB->getTerminator(), DT, LI);
}
unsigned
llvm::SplitAllCriticalEdges(Function &F,
const CriticalEdgeSplittingOptions &Options) {
unsigned NumBroken = 0;
for (Function::iterator I = F.begin(), E = F.end(); I != E; ++I) {
TerminatorInst *TI = I->getTerminator();
if (TI->getNumSuccessors() > 1 && !isa<IndirectBrInst>(TI))
for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
if (SplitCriticalEdge(TI, i, Options))
++NumBroken;
}
return NumBroken;
}
/// SplitBlock - Split the specified block at the specified instruction - every
/// thing before SplitPt stays in Old and everything starting with SplitPt moves
/// to a new block. The two blocks are joined by an unconditional branch and
/// the loop info is updated.
///
BasicBlock *llvm::SplitBlock(BasicBlock *Old, Instruction *SplitPt,
DominatorTree *DT, LoopInfo *LI) {
BasicBlock::iterator SplitIt = SplitPt;
while (isa<PHINode>(SplitIt) || isa<LandingPadInst>(SplitIt))
++SplitIt;
BasicBlock *New = Old->splitBasicBlock(SplitIt, Old->getName()+".split");
// The new block lives in whichever loop the old one did. This preserves
// LCSSA as well, because we force the split point to be after any PHI nodes.
if (LI)
if (Loop *L = LI->getLoopFor(Old))
L->addBasicBlockToLoop(New, *LI);
if (DT)
// Old dominates New. New node dominates all other nodes dominated by Old.
if (DomTreeNode *OldNode = DT->getNode(Old)) {
std::vector<DomTreeNode *> Children;
for (DomTreeNode::iterator I = OldNode->begin(), E = OldNode->end();
I != E; ++I)
Children.push_back(*I);
DomTreeNode *NewNode = DT->addNewBlock(New, Old);
for (std::vector<DomTreeNode *>::iterator I = Children.begin(),
E = Children.end(); I != E; ++I)
DT->changeImmediateDominator(*I, NewNode);
}
return New;
}
/// UpdateAnalysisInformation - Update DominatorTree, LoopInfo, and LCCSA
/// analysis information.
static void UpdateAnalysisInformation(BasicBlock *OldBB, BasicBlock *NewBB,
ArrayRef<BasicBlock *> Preds,
DominatorTree *DT, LoopInfo *LI,
bool PreserveLCSSA, bool &HasLoopExit) {
// Update dominator tree if available.
if (DT)
DT->splitBlock(NewBB);
// The rest of the logic is only relevant for updating the loop structures.
if (!LI)
return;
Loop *L = LI->getLoopFor(OldBB);
// If we need to preserve loop analyses, collect some information about how
// this split will affect loops.
bool IsLoopEntry = !!L;
bool SplitMakesNewLoopHeader = false;
for (ArrayRef<BasicBlock *>::iterator i = Preds.begin(), e = Preds.end();
i != e; ++i) {
BasicBlock *Pred = *i;
// If we need to preserve LCSSA, determine if any of the preds is a loop
// exit.
if (PreserveLCSSA)
if (Loop *PL = LI->getLoopFor(Pred))
if (!PL->contains(OldBB))
HasLoopExit = true;
// If we need to preserve LoopInfo, note whether any of the preds crosses
// an interesting loop boundary.
if (!L)
continue;
if (L->contains(Pred))
IsLoopEntry = false;
else
SplitMakesNewLoopHeader = true;
}
// Unless we have a loop for OldBB, nothing else to do here.
if (!L)
return;
if (IsLoopEntry) {
// Add the new block to the nearest enclosing loop (and not an adjacent
// loop). To find this, examine each of the predecessors and determine which
// loops enclose them, and select the most-nested loop which contains the
// loop containing the block being split.
Loop *InnermostPredLoop = nullptr;
for (ArrayRef<BasicBlock*>::iterator
i = Preds.begin(), e = Preds.end(); i != e; ++i) {
BasicBlock *Pred = *i;
if (Loop *PredLoop = LI->getLoopFor(Pred)) {
// Seek a loop which actually contains the block being split (to avoid
// adjacent loops).
while (PredLoop && !PredLoop->contains(OldBB))
PredLoop = PredLoop->getParentLoop();
// Select the most-nested of these loops which contains the block.
if (PredLoop && PredLoop->contains(OldBB) &&
(!InnermostPredLoop ||
InnermostPredLoop->getLoopDepth() < PredLoop->getLoopDepth()))
InnermostPredLoop = PredLoop;
}
}
if (InnermostPredLoop)
InnermostPredLoop->addBasicBlockToLoop(NewBB, *LI);
} else {
L->addBasicBlockToLoop(NewBB, *LI);
if (SplitMakesNewLoopHeader)
L->moveToHeader(NewBB);
}
}
/// UpdatePHINodes - Update the PHI nodes in OrigBB to include the values coming
/// from NewBB. This also updates AliasAnalysis, if available.
static void UpdatePHINodes(BasicBlock *OrigBB, BasicBlock *NewBB,
ArrayRef<BasicBlock *> Preds, BranchInst *BI,
AliasAnalysis *AA, bool HasLoopExit) {
// Otherwise, create a new PHI node in NewBB for each PHI node in OrigBB.
SmallPtrSet<BasicBlock *, 16> PredSet(Preds.begin(), Preds.end());
for (BasicBlock::iterator I = OrigBB->begin(); isa<PHINode>(I); ) {
PHINode *PN = cast<PHINode>(I++);
// Check to see if all of the values coming in are the same. If so, we
// don't need to create a new PHI node, unless it's needed for LCSSA.
Value *InVal = nullptr;
if (!HasLoopExit) {
InVal = PN->getIncomingValueForBlock(Preds[0]);
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
if (!PredSet.count(PN->getIncomingBlock(i)))
continue;
if (!InVal)
InVal = PN->getIncomingValue(i);
else if (InVal != PN->getIncomingValue(i)) {
InVal = nullptr;
break;
}
}
}
if (InVal) {
// If all incoming values for the new PHI would be the same, just don't
// make a new PHI. Instead, just remove the incoming values from the old
// PHI.
// NOTE! This loop walks backwards for a reason! First off, this minimizes
// the cost of removal if we end up removing a large number of values, and
// second off, this ensures that the indices for the incoming values
// aren't invalidated when we remove one.
for (int64_t i = PN->getNumIncomingValues() - 1; i >= 0; --i)
if (PredSet.count(PN->getIncomingBlock(i)))
PN->removeIncomingValue(i, false);
// Add an incoming value to the PHI node in the loop for the preheader
// edge.
PN->addIncoming(InVal, NewBB);
continue;
}
// If the values coming into the block are not the same, we need a new
// PHI.
// Create the new PHI node, insert it into NewBB at the end of the block
PHINode *NewPHI =
PHINode::Create(PN->getType(), Preds.size(), PN->getName() + ".ph", BI);
// NOTE! This loop walks backwards for a reason! First off, this minimizes
// the cost of removal if we end up removing a large number of values, and
// second off, this ensures that the indices for the incoming values aren't
// invalidated when we remove one.
for (int64_t i = PN->getNumIncomingValues() - 1; i >= 0; --i) {
BasicBlock *IncomingBB = PN->getIncomingBlock(i);
if (PredSet.count(IncomingBB)) {
Value *V = PN->removeIncomingValue(i, false);
NewPHI->addIncoming(V, IncomingBB);
}
}
PN->addIncoming(NewPHI, NewBB);
}
}
/// SplitBlockPredecessors - This method introduces at least one new basic block
/// into the function and moves some of the predecessors of BB to be
/// predecessors of the new block. The new predecessors are indicated by the
/// Preds array. The new block is given a suffix of 'Suffix'. Returns new basic
/// block to which predecessors from Preds are now pointing.
///
/// If BB is a landingpad block then additional basicblock might be introduced.
/// It will have suffix of 'Suffix'+".split_lp".
/// See SplitLandingPadPredecessors for more details on this case.
///
/// This currently updates the LLVM IR, AliasAnalysis, DominatorTree,
/// LoopInfo, and LCCSA but no other analyses. In particular, it does not
/// preserve LoopSimplify (because it's complicated to handle the case where one
/// of the edges being split is an exit of a loop with other exits).
///
BasicBlock *llvm::SplitBlockPredecessors(BasicBlock *BB,
ArrayRef<BasicBlock *> Preds,
const char *Suffix, AliasAnalysis *AA,
DominatorTree *DT, LoopInfo *LI,
bool PreserveLCSSA) {
// For the landingpads we need to act a bit differently.
// Delegate this work to the SplitLandingPadPredecessors.
if (BB->isLandingPad()) {
SmallVector<BasicBlock*, 2> NewBBs;
std::string NewName = std::string(Suffix) + ".split-lp";
SplitLandingPadPredecessors(BB, Preds, Suffix, NewName.c_str(),
NewBBs, AA, DT, LI, PreserveLCSSA);
return NewBBs[0];
}
// Create new basic block, insert right before the original block.
BasicBlock *NewBB = BasicBlock::Create(
BB->getContext(), BB->getName() + Suffix, BB->getParent(), BB);
// The new block unconditionally branches to the old block.
BranchInst *BI = BranchInst::Create(BB, NewBB);
BI->setDebugLoc(BB->getFirstNonPHI()->getDebugLoc());
// Move the edges from Preds to point to NewBB instead of BB.
for (unsigned i = 0, e = Preds.size(); i != e; ++i) {
// This is slightly more strict than necessary; the minimum requirement
// is that there be no more than one indirectbr branching to BB. And
// all BlockAddress uses would need to be updated.
assert(!isa<IndirectBrInst>(Preds[i]->getTerminator()) &&
"Cannot split an edge from an IndirectBrInst");
Preds[i]->getTerminator()->replaceUsesOfWith(BB, NewBB);
}
// Insert a new PHI node into NewBB for every PHI node in BB and that new PHI
// node becomes an incoming value for BB's phi node. However, if the Preds
// list is empty, we need to insert dummy entries into the PHI nodes in BB to
// account for the newly created predecessor.
if (Preds.size() == 0) {
// Insert dummy values as the incoming value.
for (BasicBlock::iterator I = BB->begin(); isa<PHINode>(I); ++I)
cast<PHINode>(I)->addIncoming(UndefValue::get(I->getType()), NewBB);
return NewBB;
}
// Update DominatorTree, LoopInfo, and LCCSA analysis information.
bool HasLoopExit = false;
UpdateAnalysisInformation(BB, NewBB, Preds, DT, LI, PreserveLCSSA,
HasLoopExit);
// Update the PHI nodes in BB with the values coming from NewBB.
UpdatePHINodes(BB, NewBB, Preds, BI, AA, HasLoopExit);
return NewBB;
}
/// SplitLandingPadPredecessors - This method transforms the landing pad,
/// OrigBB, by introducing two new basic blocks into the function. One of those
/// new basic blocks gets the predecessors listed in Preds. The other basic
/// block gets the remaining predecessors of OrigBB. The landingpad instruction
/// OrigBB is clone into both of the new basic blocks. The new blocks are given
/// the suffixes 'Suffix1' and 'Suffix2', and are returned in the NewBBs vector.
///
/// This currently updates the LLVM IR, AliasAnalysis, DominatorTree,
/// DominanceFrontier, LoopInfo, and LCCSA but no other analyses. In particular,
/// it does not preserve LoopSimplify (because it's complicated to handle the
/// case where one of the edges being split is an exit of a loop with other
/// exits).
///
void llvm::SplitLandingPadPredecessors(BasicBlock *OrigBB,
ArrayRef<BasicBlock *> Preds,
const char *Suffix1, const char *Suffix2,
SmallVectorImpl<BasicBlock *> &NewBBs,
AliasAnalysis *AA, DominatorTree *DT,
LoopInfo *LI, bool PreserveLCSSA) {
assert(OrigBB->isLandingPad() && "Trying to split a non-landing pad!");
// Create a new basic block for OrigBB's predecessors listed in Preds. Insert
// it right before the original block.
BasicBlock *NewBB1 = BasicBlock::Create(OrigBB->getContext(),
OrigBB->getName() + Suffix1,
OrigBB->getParent(), OrigBB);
NewBBs.push_back(NewBB1);
// The new block unconditionally branches to the old block.
BranchInst *BI1 = BranchInst::Create(OrigBB, NewBB1);
BI1->setDebugLoc(OrigBB->getFirstNonPHI()->getDebugLoc());
// Move the edges from Preds to point to NewBB1 instead of OrigBB.
for (unsigned i = 0, e = Preds.size(); i != e; ++i) {
// This is slightly more strict than necessary; the minimum requirement
// is that there be no more than one indirectbr branching to BB. And
// all BlockAddress uses would need to be updated.
assert(!isa<IndirectBrInst>(Preds[i]->getTerminator()) &&
"Cannot split an edge from an IndirectBrInst");
Preds[i]->getTerminator()->replaceUsesOfWith(OrigBB, NewBB1);
}
bool HasLoopExit = false;
UpdateAnalysisInformation(OrigBB, NewBB1, Preds, DT, LI, PreserveLCSSA,
HasLoopExit);
// Update the PHI nodes in OrigBB with the values coming from NewBB1.
UpdatePHINodes(OrigBB, NewBB1, Preds, BI1, AA, HasLoopExit);
// Move the remaining edges from OrigBB to point to NewBB2.
SmallVector<BasicBlock*, 8> NewBB2Preds;
for (pred_iterator i = pred_begin(OrigBB), e = pred_end(OrigBB);
i != e; ) {
BasicBlock *Pred = *i++;
if (Pred == NewBB1) continue;
assert(!isa<IndirectBrInst>(Pred->getTerminator()) &&
"Cannot split an edge from an IndirectBrInst");
NewBB2Preds.push_back(Pred);
e = pred_end(OrigBB);
}
BasicBlock *NewBB2 = nullptr;
if (!NewBB2Preds.empty()) {
// Create another basic block for the rest of OrigBB's predecessors.
NewBB2 = BasicBlock::Create(OrigBB->getContext(),
OrigBB->getName() + Suffix2,
OrigBB->getParent(), OrigBB);
NewBBs.push_back(NewBB2);
// The new block unconditionally branches to the old block.
BranchInst *BI2 = BranchInst::Create(OrigBB, NewBB2);
BI2->setDebugLoc(OrigBB->getFirstNonPHI()->getDebugLoc());
// Move the remaining edges from OrigBB to point to NewBB2.
for (SmallVectorImpl<BasicBlock*>::iterator
i = NewBB2Preds.begin(), e = NewBB2Preds.end(); i != e; ++i)
(*i)->getTerminator()->replaceUsesOfWith(OrigBB, NewBB2);
// Update DominatorTree, LoopInfo, and LCCSA analysis information.
HasLoopExit = false;
UpdateAnalysisInformation(OrigBB, NewBB2, NewBB2Preds, DT, LI,
PreserveLCSSA, HasLoopExit);
// Update the PHI nodes in OrigBB with the values coming from NewBB2.
UpdatePHINodes(OrigBB, NewBB2, NewBB2Preds, BI2, AA, HasLoopExit);
}
LandingPadInst *LPad = OrigBB->getLandingPadInst();
Instruction *Clone1 = LPad->clone();
Clone1->setName(Twine("lpad") + Suffix1);
NewBB1->getInstList().insert(NewBB1->getFirstInsertionPt(), Clone1);
if (NewBB2) {
Instruction *Clone2 = LPad->clone();
Clone2->setName(Twine("lpad") + Suffix2);
NewBB2->getInstList().insert(NewBB2->getFirstInsertionPt(), Clone2);
// Create a PHI node for the two cloned landingpad instructions.
PHINode *PN = PHINode::Create(LPad->getType(), 2, "lpad.phi", LPad);
PN->addIncoming(Clone1, NewBB1);
PN->addIncoming(Clone2, NewBB2);
LPad->replaceAllUsesWith(PN);
LPad->eraseFromParent();
} else {
// There is no second clone. Just replace the landing pad with the first
// clone.
LPad->replaceAllUsesWith(Clone1);
LPad->eraseFromParent();
}
}
/// FoldReturnIntoUncondBranch - This method duplicates the specified return
/// instruction into a predecessor which ends in an unconditional branch. If
/// the return instruction returns a value defined by a PHI, propagate the
/// right value into the return. It returns the new return instruction in the
/// predecessor.
ReturnInst *llvm::FoldReturnIntoUncondBranch(ReturnInst *RI, BasicBlock *BB,
BasicBlock *Pred) {
Instruction *UncondBranch = Pred->getTerminator();
// Clone the return and add it to the end of the predecessor.
Instruction *NewRet = RI->clone();
Pred->getInstList().push_back(NewRet);
// If the return instruction returns a value, and if the value was a
// PHI node in "BB", propagate the right value into the return.
for (User::op_iterator i = NewRet->op_begin(), e = NewRet->op_end();
i != e; ++i) {
Value *V = *i;
Instruction *NewBC = nullptr;
if (BitCastInst *BCI = dyn_cast<BitCastInst>(V)) {
// Return value might be bitcasted. Clone and insert it before the
// return instruction.
V = BCI->getOperand(0);
NewBC = BCI->clone();
Pred->getInstList().insert(NewRet, NewBC);
*i = NewBC;
}
if (PHINode *PN = dyn_cast<PHINode>(V)) {
if (PN->getParent() == BB) {
if (NewBC)
NewBC->setOperand(0, PN->getIncomingValueForBlock(Pred));
else
*i = PN->getIncomingValueForBlock(Pred);
}
}
}
// Update any PHI nodes in the returning block to realize that we no
// longer branch to them.
BB->removePredecessor(Pred);
UncondBranch->eraseFromParent();
return cast<ReturnInst>(NewRet);
}
/// SplitBlockAndInsertIfThen - Split the containing block at the
/// specified instruction - everything before and including SplitBefore stays
/// in the old basic block, and everything after SplitBefore is moved to a
/// new block. The two blocks are connected by a conditional branch
/// (with value of Cmp being the condition).
/// Before:
/// Head
/// SplitBefore
/// Tail
/// After:
/// Head
/// if (Cond)
/// ThenBlock
/// SplitBefore
/// Tail
///
/// If Unreachable is true, then ThenBlock ends with
/// UnreachableInst, otherwise it branches to Tail.
/// Returns the NewBasicBlock's terminator.
TerminatorInst *llvm::SplitBlockAndInsertIfThen(Value *Cond,
Instruction *SplitBefore,
bool Unreachable,
MDNode *BranchWeights,
DominatorTree *DT) {
BasicBlock *Head = SplitBefore->getParent();
BasicBlock *Tail = Head->splitBasicBlock(SplitBefore);
TerminatorInst *HeadOldTerm = Head->getTerminator();
LLVMContext &C = Head->getContext();
BasicBlock *ThenBlock = BasicBlock::Create(C, "", Head->getParent(), Tail);
TerminatorInst *CheckTerm;
if (Unreachable)
CheckTerm = new UnreachableInst(C, ThenBlock);
else
CheckTerm = BranchInst::Create(Tail, ThenBlock);
CheckTerm->setDebugLoc(SplitBefore->getDebugLoc());
BranchInst *HeadNewTerm =
BranchInst::Create(/*ifTrue*/ThenBlock, /*ifFalse*/Tail, Cond);
HeadNewTerm->setMetadata(LLVMContext::MD_prof, BranchWeights);
ReplaceInstWithInst(HeadOldTerm, HeadNewTerm);
if (DT) {
if (DomTreeNode *OldNode = DT->getNode(Head)) {
std::vector<DomTreeNode *> Children(OldNode->begin(), OldNode->end());
DomTreeNode *NewNode = DT->addNewBlock(Tail, Head);
for (auto Child : Children)
DT->changeImmediateDominator(Child, NewNode);
// Head dominates ThenBlock.
DT->addNewBlock(ThenBlock, Head);
}
}
return CheckTerm;
}
/// SplitBlockAndInsertIfThenElse is similar to SplitBlockAndInsertIfThen,
/// but also creates the ElseBlock.
/// Before:
/// Head
/// SplitBefore
/// Tail
/// After:
/// Head
/// if (Cond)
/// ThenBlock
/// else
/// ElseBlock
/// SplitBefore
/// Tail
void llvm::SplitBlockAndInsertIfThenElse(Value *Cond, Instruction *SplitBefore,
TerminatorInst **ThenTerm,
TerminatorInst **ElseTerm,
MDNode *BranchWeights) {
BasicBlock *Head = SplitBefore->getParent();
BasicBlock *Tail = Head->splitBasicBlock(SplitBefore);
TerminatorInst *HeadOldTerm = Head->getTerminator();
LLVMContext &C = Head->getContext();
BasicBlock *ThenBlock = BasicBlock::Create(C, "", Head->getParent(), Tail);
BasicBlock *ElseBlock = BasicBlock::Create(C, "", Head->getParent(), Tail);
*ThenTerm = BranchInst::Create(Tail, ThenBlock);
(*ThenTerm)->setDebugLoc(SplitBefore->getDebugLoc());
*ElseTerm = BranchInst::Create(Tail, ElseBlock);
(*ElseTerm)->setDebugLoc(SplitBefore->getDebugLoc());
BranchInst *HeadNewTerm =
BranchInst::Create(/*ifTrue*/ThenBlock, /*ifFalse*/ElseBlock, Cond);
HeadNewTerm->setMetadata(LLVMContext::MD_prof, BranchWeights);
ReplaceInstWithInst(HeadOldTerm, HeadNewTerm);
}
/// GetIfCondition - Given a basic block (BB) with two predecessors,
/// check to see if the merge at this block is due
/// to an "if condition". If so, return the boolean condition that determines
/// which entry into BB will be taken. Also, return by references the block
/// that will be entered from if the condition is true, and the block that will
/// be entered if the condition is false.
///
/// This does no checking to see if the true/false blocks have large or unsavory
/// instructions in them.
Value *llvm::GetIfCondition(BasicBlock *BB, BasicBlock *&IfTrue,
BasicBlock *&IfFalse) {
PHINode *SomePHI = dyn_cast<PHINode>(BB->begin());
BasicBlock *Pred1 = nullptr;
BasicBlock *Pred2 = nullptr;
if (SomePHI) {
if (SomePHI->getNumIncomingValues() != 2)
return nullptr;
Pred1 = SomePHI->getIncomingBlock(0);
Pred2 = SomePHI->getIncomingBlock(1);
} else {
pred_iterator PI = pred_begin(BB), PE = pred_end(BB);
if (PI == PE) // No predecessor
return nullptr;
Pred1 = *PI++;
if (PI == PE) // Only one predecessor
return nullptr;
Pred2 = *PI++;
if (PI != PE) // More than two predecessors
return nullptr;
}
// We can only handle branches. Other control flow will be lowered to
// branches if possible anyway.
BranchInst *Pred1Br = dyn_cast<BranchInst>(Pred1->getTerminator());
BranchInst *Pred2Br = dyn_cast<BranchInst>(Pred2->getTerminator());
if (!Pred1Br || !Pred2Br)
return nullptr;
// Eliminate code duplication by ensuring that Pred1Br is conditional if
// either are.
if (Pred2Br->isConditional()) {
// If both branches are conditional, we don't have an "if statement". In
// reality, we could transform this case, but since the condition will be
// required anyway, we stand no chance of eliminating it, so the xform is
// probably not profitable.
if (Pred1Br->isConditional())
return nullptr;
std::swap(Pred1, Pred2);
std::swap(Pred1Br, Pred2Br);
}
if (Pred1Br->isConditional()) {
// The only thing we have to watch out for here is to make sure that Pred2
// doesn't have incoming edges from other blocks. If it does, the condition
// doesn't dominate BB.
if (!Pred2->getSinglePredecessor())
return nullptr;
// If we found a conditional branch predecessor, make sure that it branches
// to BB and Pred2Br. If it doesn't, this isn't an "if statement".
if (Pred1Br->getSuccessor(0) == BB &&
Pred1Br->getSuccessor(1) == Pred2) {
IfTrue = Pred1;
IfFalse = Pred2;
} else if (Pred1Br->getSuccessor(0) == Pred2 &&
Pred1Br->getSuccessor(1) == BB) {
IfTrue = Pred2;
IfFalse = Pred1;
} else {
// We know that one arm of the conditional goes to BB, so the other must
// go somewhere unrelated, and this must not be an "if statement".
return nullptr;
}
return Pred1Br->getCondition();
}
// Ok, if we got here, both predecessors end with an unconditional branch to
// BB. Don't panic! If both blocks only have a single (identical)
// predecessor, and THAT is a conditional branch, then we're all ok!
BasicBlock *CommonPred = Pred1->getSinglePredecessor();
if (CommonPred == nullptr || CommonPred != Pred2->getSinglePredecessor())
return nullptr;
// Otherwise, if this is a conditional branch, then we can use it!
BranchInst *BI = dyn_cast<BranchInst>(CommonPred->getTerminator());
if (!BI) return nullptr;
assert(BI->isConditional() && "Two successors but not conditional?");
if (BI->getSuccessor(0) == Pred1) {
IfTrue = Pred1;
IfFalse = Pred2;
} else {
IfTrue = Pred2;
IfFalse = Pred1;
}
return BI->getCondition();
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/ModuleUtils.cpp | //===-- ModuleUtils.cpp - Functions to manipulate Modules -----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This family of functions perform manipulations on Modules.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/ModuleUtils.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
static void appendToGlobalArray(const char *Array,
Module &M, Function *F, int Priority) {
IRBuilder<> IRB(M.getContext());
FunctionType *FnTy = FunctionType::get(IRB.getVoidTy(), false);
// Get the current set of static global constructors and add the new ctor
// to the list.
SmallVector<Constant *, 16> CurrentCtors;
StructType *EltTy;
if (GlobalVariable *GVCtor = M.getNamedGlobal(Array)) {
// If there is a global_ctors array, use the existing struct type, which can
// have 2 or 3 fields.
ArrayType *ATy = cast<ArrayType>(GVCtor->getType()->getElementType());
EltTy = cast<StructType>(ATy->getElementType());
if (Constant *Init = GVCtor->getInitializer()) {
unsigned n = Init->getNumOperands();
CurrentCtors.reserve(n + 1);
for (unsigned i = 0; i != n; ++i)
CurrentCtors.push_back(cast<Constant>(Init->getOperand(i)));
}
GVCtor->eraseFromParent();
} else {
// Use a simple two-field struct if there isn't one already.
EltTy = StructType::get(IRB.getInt32Ty(), PointerType::getUnqual(FnTy),
nullptr);
}
// Build a 2 or 3 field global_ctor entry. We don't take a comdat key.
Constant *CSVals[3];
CSVals[0] = IRB.getInt32(Priority);
CSVals[1] = F;
// FIXME: Drop support for the two element form in LLVM 4.0.
if (EltTy->getNumElements() >= 3)
CSVals[2] = llvm::Constant::getNullValue(IRB.getInt8PtrTy());
Constant *RuntimeCtorInit =
ConstantStruct::get(EltTy, makeArrayRef(CSVals, EltTy->getNumElements()));
CurrentCtors.push_back(RuntimeCtorInit);
// Create a new initializer.
ArrayType *AT = ArrayType::get(EltTy, CurrentCtors.size());
Constant *NewInit = ConstantArray::get(AT, CurrentCtors);
// Create the new global variable and replace all uses of
// the old global variable with the new one.
(void)new GlobalVariable(M, NewInit->getType(), false,
GlobalValue::AppendingLinkage, NewInit, Array);
}
void llvm::appendToGlobalCtors(Module &M, Function *F, int Priority) {
appendToGlobalArray("llvm.global_ctors", M, F, Priority);
}
void llvm::appendToGlobalDtors(Module &M, Function *F, int Priority) {
appendToGlobalArray("llvm.global_dtors", M, F, Priority);
}
GlobalVariable *
llvm::collectUsedGlobalVariables(Module &M, SmallPtrSetImpl<GlobalValue *> &Set,
bool CompilerUsed) {
const char *Name = CompilerUsed ? "llvm.compiler.used" : "llvm.used";
GlobalVariable *GV = M.getGlobalVariable(Name);
if (!GV || !GV->hasInitializer())
return GV;
const ConstantArray *Init = cast<ConstantArray>(GV->getInitializer());
for (unsigned I = 0, E = Init->getNumOperands(); I != E; ++I) {
Value *Op = Init->getOperand(I);
GlobalValue *G = cast<GlobalValue>(Op->stripPointerCastsNoFollowAliases());
Set.insert(G);
}
return GV;
}
Function *llvm::checkSanitizerInterfaceFunction(Constant *FuncOrBitcast) {
if (isa<Function>(FuncOrBitcast))
return cast<Function>(FuncOrBitcast);
FuncOrBitcast->dump();
std::string Err;
raw_string_ostream Stream(Err);
Stream << "Sanitizer interface function redefined: " << *FuncOrBitcast;
report_fatal_error(Err);
}
std::pair<Function *, Function *> llvm::createSanitizerCtorAndInitFunctions(
Module &M, StringRef CtorName, StringRef InitName,
ArrayRef<Type *> InitArgTypes, ArrayRef<Value *> InitArgs) {
assert(!InitName.empty() && "Expected init function name");
assert(InitArgTypes.size() == InitArgTypes.size() &&
"Sanitizer's init function expects different number of arguments");
Function *Ctor = Function::Create(
FunctionType::get(Type::getVoidTy(M.getContext()), false),
GlobalValue::InternalLinkage, CtorName, &M);
BasicBlock *CtorBB = BasicBlock::Create(M.getContext(), "", Ctor);
IRBuilder<> IRB(ReturnInst::Create(M.getContext(), CtorBB));
Function *InitFunction =
checkSanitizerInterfaceFunction(M.getOrInsertFunction(
InitName, FunctionType::get(IRB.getVoidTy(), InitArgTypes, false),
AttributeSet()));
InitFunction->setLinkage(Function::ExternalLinkage);
IRB.CreateCall(InitFunction, InitArgs);
return std::make_pair(Ctor, InitFunction);
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/FlattenCFG.cpp | //===- FlatternCFG.cpp - Code to perform CFG flattening ---------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Reduce conditional branches in CFG.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
using namespace llvm;
#define DEBUG_TYPE "flattencfg"
namespace {
class FlattenCFGOpt {
AliasAnalysis *AA;
/// \brief Use parallel-and or parallel-or to generate conditions for
/// conditional branches.
bool FlattenParallelAndOr(BasicBlock *BB, IRBuilder<> &Builder,
Pass *P = nullptr);
/// \brief If \param BB is the merge block of an if-region, attempt to merge
/// the if-region with an adjacent if-region upstream if two if-regions
/// contain identical instructions.
bool MergeIfRegion(BasicBlock *BB, IRBuilder<> &Builder, Pass *P = nullptr);
/// \brief Compare a pair of blocks: \p Block1 and \p Block2, which
/// are from two if-regions whose entry blocks are \p Head1 and \p
/// Head2. \returns true if \p Block1 and \p Block2 contain identical
/// instructions, and have no memory reference alias with \p Head2.
/// This is used as a legality check for merging if-regions.
bool CompareIfRegionBlock(BasicBlock *Head1, BasicBlock *Head2,
BasicBlock *Block1, BasicBlock *Block2);
public:
FlattenCFGOpt(AliasAnalysis *AA) : AA(AA) {}
bool run(BasicBlock *BB);
};
}
/// If \param [in] BB has more than one predecessor that is a conditional
/// branch, attempt to use parallel and/or for the branch condition. \returns
/// true on success.
///
/// Before:
/// ......
/// %cmp10 = fcmp une float %tmp1, %tmp2
/// br i1 %cmp1, label %if.then, label %lor.rhs
///
/// lor.rhs:
/// ......
/// %cmp11 = fcmp une float %tmp3, %tmp4
/// br i1 %cmp11, label %if.then, label %ifend
///
/// if.end: // the merge block
/// ......
///
/// if.then: // has two predecessors, both of them contains conditional branch.
/// ......
/// br label %if.end;
///
/// After:
/// ......
/// %cmp10 = fcmp une float %tmp1, %tmp2
/// ......
/// %cmp11 = fcmp une float %tmp3, %tmp4
/// %cmp12 = or i1 %cmp10, %cmp11 // parallel-or mode.
/// br i1 %cmp12, label %if.then, label %ifend
///
/// if.end:
/// ......
///
/// if.then:
/// ......
/// br label %if.end;
///
/// Current implementation handles two cases.
/// Case 1: \param BB is on the else-path.
///
/// BB1
/// / |
/// BB2 |
/// / \ |
/// BB3 \ | where, BB1, BB2 contain conditional branches.
/// \ | / BB3 contains unconditional branch.
/// \ | / BB4 corresponds to \param BB which is also the merge.
/// BB => BB4
///
///
/// Corresponding source code:
///
/// if (a == b && c == d)
/// statement; // BB3
///
/// Case 2: \param BB BB is on the then-path.
///
/// BB1
/// / |
/// | BB2
/// \ / | where BB1, BB2 contain conditional branches.
/// BB => BB3 | BB3 contains unconditiona branch and corresponds
/// \ / to \param BB. BB4 is the merge.
/// BB4
///
/// Corresponding source code:
///
/// if (a == b || c == d)
/// statement; // BB3
///
/// In both cases, \param BB is the common successor of conditional branches.
/// In Case 1, \param BB (BB4) has an unconditional branch (BB3) as
/// its predecessor. In Case 2, \param BB (BB3) only has conditional branches
/// as its predecessors.
///
bool FlattenCFGOpt::FlattenParallelAndOr(BasicBlock *BB, IRBuilder<> &Builder,
Pass *P) {
PHINode *PHI = dyn_cast<PHINode>(BB->begin());
if (PHI)
return false; // For simplicity, avoid cases containing PHI nodes.
BasicBlock *LastCondBlock = nullptr;
BasicBlock *FirstCondBlock = nullptr;
BasicBlock *UnCondBlock = nullptr;
int Idx = -1;
// Check predecessors of \param BB.
SmallPtrSet<BasicBlock *, 16> Preds(pred_begin(BB), pred_end(BB));
for (SmallPtrSetIterator<BasicBlock *> PI = Preds.begin(), PE = Preds.end();
PI != PE; ++PI) {
BasicBlock *Pred = *PI;
BranchInst *PBI = dyn_cast<BranchInst>(Pred->getTerminator());
// All predecessors should terminate with a branch.
if (!PBI)
return false;
BasicBlock *PP = Pred->getSinglePredecessor();
if (PBI->isUnconditional()) {
// Case 1: Pred (BB3) is an unconditional block, it should
// have a single predecessor (BB2) that is also a predecessor
// of \param BB (BB4) and should not have address-taken.
// There should exist only one such unconditional
// branch among the predecessors.
if (UnCondBlock || !PP || (Preds.count(PP) == 0) ||
Pred->hasAddressTaken())
return false;
UnCondBlock = Pred;
continue;
}
// Only conditional branches are allowed beyond this point.
assert(PBI->isConditional());
// Condition's unique use should be the branch instruction.
Value *PC = PBI->getCondition();
if (!PC || !PC->hasOneUse())
return false;
if (PP && Preds.count(PP)) {
// These are internal condition blocks to be merged from, e.g.,
// BB2 in both cases.
// Should not be address-taken.
if (Pred->hasAddressTaken())
return false;
// Instructions in the internal condition blocks should be safe
// to hoist up.
for (BasicBlock::iterator BI = Pred->begin(), BE = PBI; BI != BE;) {
Instruction *CI = BI++;
if (isa<PHINode>(CI) || !isSafeToSpeculativelyExecute(CI))
return false;
}
} else {
// This is the condition block to be merged into, e.g. BB1 in
// both cases.
if (FirstCondBlock)
return false;
FirstCondBlock = Pred;
}
// Find whether BB is uniformly on the true (or false) path
// for all of its predecessors.
BasicBlock *PS1 = PBI->getSuccessor(0);
BasicBlock *PS2 = PBI->getSuccessor(1);
BasicBlock *PS = (PS1 == BB) ? PS2 : PS1;
int CIdx = (PS1 == BB) ? 0 : 1;
if (Idx == -1)
Idx = CIdx;
else if (CIdx != Idx)
return false;
// PS is the successor which is not BB. Check successors to identify
// the last conditional branch.
if (Preds.count(PS) == 0) {
// Case 2.
LastCondBlock = Pred;
} else {
// Case 1
BranchInst *BPS = dyn_cast<BranchInst>(PS->getTerminator());
if (BPS && BPS->isUnconditional()) {
// Case 1: PS(BB3) should be an unconditional branch.
LastCondBlock = Pred;
}
}
}
if (!FirstCondBlock || !LastCondBlock || (FirstCondBlock == LastCondBlock))
return false;
TerminatorInst *TBB = LastCondBlock->getTerminator();
BasicBlock *PS1 = TBB->getSuccessor(0);
BasicBlock *PS2 = TBB->getSuccessor(1);
BranchInst *PBI1 = dyn_cast<BranchInst>(PS1->getTerminator());
BranchInst *PBI2 = dyn_cast<BranchInst>(PS2->getTerminator());
// If PS1 does not jump into PS2, but PS2 jumps into PS1,
// attempt branch inversion.
if (!PBI1 || !PBI1->isUnconditional() ||
(PS1->getTerminator()->getSuccessor(0) != PS2)) {
// Check whether PS2 jumps into PS1.
if (!PBI2 || !PBI2->isUnconditional() ||
(PS2->getTerminator()->getSuccessor(0) != PS1))
return false;
// Do branch inversion.
BasicBlock *CurrBlock = LastCondBlock;
bool EverChanged = false;
for (;CurrBlock != FirstCondBlock;
CurrBlock = CurrBlock->getSinglePredecessor()) {
BranchInst *BI = dyn_cast<BranchInst>(CurrBlock->getTerminator());
CmpInst *CI = dyn_cast<CmpInst>(BI->getCondition());
if (!CI)
continue;
CmpInst::Predicate Predicate = CI->getPredicate();
// Canonicalize icmp_ne -> icmp_eq, fcmp_one -> fcmp_oeq
if ((Predicate == CmpInst::ICMP_NE) || (Predicate == CmpInst::FCMP_ONE)) {
CI->setPredicate(ICmpInst::getInversePredicate(Predicate));
BI->swapSuccessors();
EverChanged = true;
}
}
return EverChanged;
}
// PS1 must have a conditional branch.
if (!PBI1 || !PBI1->isUnconditional())
return false;
// PS2 should not contain PHI node.
PHI = dyn_cast<PHINode>(PS2->begin());
if (PHI)
return false;
// Do the transformation.
BasicBlock *CB;
BranchInst *PBI = dyn_cast<BranchInst>(FirstCondBlock->getTerminator());
bool Iteration = true;
IRBuilder<>::InsertPointGuard Guard(Builder);
Value *PC = PBI->getCondition();
do {
CB = PBI->getSuccessor(1 - Idx);
// Delete the conditional branch.
FirstCondBlock->getInstList().pop_back();
FirstCondBlock->getInstList()
.splice(FirstCondBlock->end(), CB->getInstList());
PBI = cast<BranchInst>(FirstCondBlock->getTerminator());
Value *CC = PBI->getCondition();
// Merge conditions.
Builder.SetInsertPoint(PBI);
Value *NC;
if (Idx == 0)
// Case 2, use parallel or.
NC = Builder.CreateOr(PC, CC);
else
// Case 1, use parallel and.
NC = Builder.CreateAnd(PC, CC);
PBI->replaceUsesOfWith(CC, NC);
PC = NC;
if (CB == LastCondBlock)
Iteration = false;
// Remove internal conditional branches.
CB->dropAllReferences();
// make CB unreachable and let downstream to delete the block.
new UnreachableInst(CB->getContext(), CB);
} while (Iteration);
DEBUG(dbgs() << "Use parallel and/or in:\n" << *FirstCondBlock);
return true;
}
/// Compare blocks from two if-regions, where \param Head1 is the entry of the
/// 1st if-region. \param Head2 is the entry of the 2nd if-region. \param
/// Block1 is a block in the 1st if-region to compare. \param Block2 is a block
// in the 2nd if-region to compare. \returns true if \param Block1 and \param
/// Block2 have identical instructions and do not have memory reference alias
/// with \param Head2.
///
bool FlattenCFGOpt::CompareIfRegionBlock(BasicBlock *Head1, BasicBlock *Head2,
BasicBlock *Block1,
BasicBlock *Block2) {
TerminatorInst *PTI2 = Head2->getTerminator();
Instruction *PBI2 = Head2->begin();
bool eq1 = (Block1 == Head1);
bool eq2 = (Block2 == Head2);
if (eq1 || eq2) {
// An empty then-path or else-path.
return (eq1 == eq2);
}
// Check whether instructions in Block1 and Block2 are identical
// and do not alias with instructions in Head2.
BasicBlock::iterator iter1 = Block1->begin();
BasicBlock::iterator end1 = Block1->getTerminator();
BasicBlock::iterator iter2 = Block2->begin();
BasicBlock::iterator end2 = Block2->getTerminator();
while (1) {
if (iter1 == end1) {
if (iter2 != end2)
return false;
break;
}
if (!iter1->isIdenticalTo(iter2))
return false;
// Illegal to remove instructions with side effects except
// non-volatile stores.
if (iter1->mayHaveSideEffects()) {
Instruction *CurI = &*iter1;
StoreInst *SI = dyn_cast<StoreInst>(CurI);
if (!SI || SI->isVolatile())
return false;
}
// For simplicity and speed, data dependency check can be
// avoided if read from memory doesn't exist.
if (iter1->mayReadFromMemory())
return false;
if (iter1->mayWriteToMemory()) {
for (BasicBlock::iterator BI = PBI2, BE = PTI2; BI != BE; ++BI) {
if (BI->mayReadFromMemory() || BI->mayWriteToMemory()) {
// Check alias with Head2.
if (!AA || AA->alias(iter1, BI))
return false;
}
}
}
++iter1;
++iter2;
}
return true;
}
/// Check whether \param BB is the merge block of a if-region. If yes, check
/// whether there exists an adjacent if-region upstream, the two if-regions
/// contain identical instructions and can be legally merged. \returns true if
/// the two if-regions are merged.
///
/// From:
/// if (a)
/// statement;
/// if (b)
/// statement;
///
/// To:
/// if (a || b)
/// statement;
///
bool FlattenCFGOpt::MergeIfRegion(BasicBlock *BB, IRBuilder<> &Builder,
Pass *P) {
BasicBlock *IfTrue2, *IfFalse2;
Value *IfCond2 = GetIfCondition(BB, IfTrue2, IfFalse2);
Instruction *CInst2 = dyn_cast_or_null<Instruction>(IfCond2);
if (!CInst2)
return false;
BasicBlock *SecondEntryBlock = CInst2->getParent();
if (SecondEntryBlock->hasAddressTaken())
return false;
BasicBlock *IfTrue1, *IfFalse1;
Value *IfCond1 = GetIfCondition(SecondEntryBlock, IfTrue1, IfFalse1);
Instruction *CInst1 = dyn_cast_or_null<Instruction>(IfCond1);
if (!CInst1)
return false;
BasicBlock *FirstEntryBlock = CInst1->getParent();
// Either then-path or else-path should be empty.
if ((IfTrue1 != FirstEntryBlock) && (IfFalse1 != FirstEntryBlock))
return false;
if ((IfTrue2 != SecondEntryBlock) && (IfFalse2 != SecondEntryBlock))
return false;
TerminatorInst *PTI2 = SecondEntryBlock->getTerminator();
Instruction *PBI2 = SecondEntryBlock->begin();
if (!CompareIfRegionBlock(FirstEntryBlock, SecondEntryBlock, IfTrue1,
IfTrue2))
return false;
if (!CompareIfRegionBlock(FirstEntryBlock, SecondEntryBlock, IfFalse1,
IfFalse2))
return false;
// Check whether \param SecondEntryBlock has side-effect and is safe to
// speculate.
for (BasicBlock::iterator BI = PBI2, BE = PTI2; BI != BE; ++BI) {
Instruction *CI = BI;
if (isa<PHINode>(CI) || CI->mayHaveSideEffects() ||
!isSafeToSpeculativelyExecute(CI))
return false;
}
// Merge \param SecondEntryBlock into \param FirstEntryBlock.
FirstEntryBlock->getInstList().pop_back();
FirstEntryBlock->getInstList()
.splice(FirstEntryBlock->end(), SecondEntryBlock->getInstList());
BranchInst *PBI = dyn_cast<BranchInst>(FirstEntryBlock->getTerminator());
Value *CC = PBI->getCondition();
BasicBlock *SaveInsertBB = Builder.GetInsertBlock();
BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint();
Builder.SetInsertPoint(PBI);
Value *NC = Builder.CreateOr(CInst1, CC);
PBI->replaceUsesOfWith(CC, NC);
Builder.SetInsertPoint(SaveInsertBB, SaveInsertPt);
// Remove IfTrue1
if (IfTrue1 != FirstEntryBlock) {
IfTrue1->dropAllReferences();
IfTrue1->eraseFromParent();
}
// Remove IfFalse1
if (IfFalse1 != FirstEntryBlock) {
IfFalse1->dropAllReferences();
IfFalse1->eraseFromParent();
}
// Remove \param SecondEntryBlock
SecondEntryBlock->dropAllReferences();
SecondEntryBlock->eraseFromParent();
DEBUG(dbgs() << "If conditions merged into:\n" << *FirstEntryBlock);
return true;
}
bool FlattenCFGOpt::run(BasicBlock *BB) {
bool Changed = false;
assert(BB && BB->getParent() && "Block not embedded in function!");
assert(BB->getTerminator() && "Degenerate basic block encountered!");
IRBuilder<> Builder(BB);
if (FlattenParallelAndOr(BB, Builder))
return true;
if (MergeIfRegion(BB, Builder))
return true;
return Changed;
}
/// FlattenCFG - This function is used to flatten a CFG. For
/// example, it uses parallel-and and parallel-or mode to collapse
// if-conditions and merge if-regions with identical statements.
///
bool llvm::FlattenCFG(BasicBlock *BB, AliasAnalysis *AA) {
return FlattenCFGOpt(AA).run(BB);
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/BypassSlowDivision.cpp | //===-- BypassSlowDivision.cpp - Bypass slow division ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains an optimization for div and rem on architectures that
// execute short instructions significantly faster than longer instructions.
// For example, on Intel Atom 32-bit divides are slow enough that during
// runtime it is profitable to check the value of the operands, and if they are
// positive and less than 256 use an unsigned 8-bit divide.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/BypassSlowDivision.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instructions.h"
using namespace llvm;
#define DEBUG_TYPE "bypass-slow-division"
namespace {
struct DivOpInfo {
bool SignedOp;
Value *Dividend;
Value *Divisor;
DivOpInfo(bool InSignedOp, Value *InDividend, Value *InDivisor)
: SignedOp(InSignedOp), Dividend(InDividend), Divisor(InDivisor) {}
};
struct DivPhiNodes {
PHINode *Quotient;
PHINode *Remainder;
DivPhiNodes(PHINode *InQuotient, PHINode *InRemainder)
: Quotient(InQuotient), Remainder(InRemainder) {}
};
}
namespace llvm {
template<>
struct DenseMapInfo<DivOpInfo> {
static bool isEqual(const DivOpInfo &Val1, const DivOpInfo &Val2) {
return Val1.SignedOp == Val2.SignedOp &&
Val1.Dividend == Val2.Dividend &&
Val1.Divisor == Val2.Divisor;
}
static DivOpInfo getEmptyKey() {
return DivOpInfo(false, nullptr, nullptr);
}
static DivOpInfo getTombstoneKey() {
return DivOpInfo(true, nullptr, nullptr);
}
static unsigned getHashValue(const DivOpInfo &Val) {
return (unsigned)(reinterpret_cast<uintptr_t>(Val.Dividend) ^
reinterpret_cast<uintptr_t>(Val.Divisor)) ^
(unsigned)Val.SignedOp;
}
};
typedef DenseMap<DivOpInfo, DivPhiNodes> DivCacheTy;
}
// insertFastDiv - Substitutes the div/rem instruction with code that checks the
// value of the operands and uses a shorter-faster div/rem instruction when
// possible and the longer-slower div/rem instruction otherwise.
static bool insertFastDiv(Function &F,
Function::iterator &I,
BasicBlock::iterator &J,
IntegerType *BypassType,
bool UseDivOp,
bool UseSignedOp,
DivCacheTy &PerBBDivCache) {
// Get instruction operands
Instruction *Instr = J;
Value *Dividend = Instr->getOperand(0);
Value *Divisor = Instr->getOperand(1);
if (isa<ConstantInt>(Divisor) ||
(isa<ConstantInt>(Dividend) && isa<ConstantInt>(Divisor))) {
// Operations with immediate values should have
// been solved and replaced during compile time.
return false;
}
// Basic Block is split before divide
BasicBlock *MainBB = I;
BasicBlock *SuccessorBB = I->splitBasicBlock(J);
++I; //advance iterator I to successorBB
// Add new basic block for slow divide operation
BasicBlock *SlowBB = BasicBlock::Create(F.getContext(), "",
MainBB->getParent(), SuccessorBB);
SlowBB->moveBefore(SuccessorBB);
IRBuilder<> SlowBuilder(SlowBB, SlowBB->begin());
Value *SlowQuotientV;
Value *SlowRemainderV;
if (UseSignedOp) {
SlowQuotientV = SlowBuilder.CreateSDiv(Dividend, Divisor);
SlowRemainderV = SlowBuilder.CreateSRem(Dividend, Divisor);
} else {
SlowQuotientV = SlowBuilder.CreateUDiv(Dividend, Divisor);
SlowRemainderV = SlowBuilder.CreateURem(Dividend, Divisor);
}
SlowBuilder.CreateBr(SuccessorBB);
// Add new basic block for fast divide operation
BasicBlock *FastBB = BasicBlock::Create(F.getContext(), "",
MainBB->getParent(), SuccessorBB);
FastBB->moveBefore(SlowBB);
IRBuilder<> FastBuilder(FastBB, FastBB->begin());
Value *ShortDivisorV = FastBuilder.CreateCast(Instruction::Trunc, Divisor,
BypassType);
Value *ShortDividendV = FastBuilder.CreateCast(Instruction::Trunc, Dividend,
BypassType);
// udiv/urem because optimization only handles positive numbers
Value *ShortQuotientV = FastBuilder.CreateExactUDiv(ShortDividendV,
ShortDivisorV);
Value *ShortRemainderV = FastBuilder.CreateURem(ShortDividendV,
ShortDivisorV);
Value *FastQuotientV = FastBuilder.CreateCast(Instruction::ZExt,
ShortQuotientV,
Dividend->getType());
Value *FastRemainderV = FastBuilder.CreateCast(Instruction::ZExt,
ShortRemainderV,
Dividend->getType());
FastBuilder.CreateBr(SuccessorBB);
// Phi nodes for result of div and rem
IRBuilder<> SuccessorBuilder(SuccessorBB, SuccessorBB->begin());
PHINode *QuoPhi = SuccessorBuilder.CreatePHI(Instr->getType(), 2);
QuoPhi->addIncoming(SlowQuotientV, SlowBB);
QuoPhi->addIncoming(FastQuotientV, FastBB);
PHINode *RemPhi = SuccessorBuilder.CreatePHI(Instr->getType(), 2);
RemPhi->addIncoming(SlowRemainderV, SlowBB);
RemPhi->addIncoming(FastRemainderV, FastBB);
// Replace Instr with appropriate phi node
if (UseDivOp)
Instr->replaceAllUsesWith(QuoPhi);
else
Instr->replaceAllUsesWith(RemPhi);
Instr->eraseFromParent();
// Combine operands into a single value with OR for value testing below
MainBB->getInstList().back().eraseFromParent();
IRBuilder<> MainBuilder(MainBB, MainBB->end());
Value *OrV = MainBuilder.CreateOr(Dividend, Divisor);
// BitMask is inverted to check if the operands are
// larger than the bypass type
uint64_t BitMask = ~BypassType->getBitMask();
Value *AndV = MainBuilder.CreateAnd(OrV, BitMask);
// Compare operand values and branch
Value *ZeroV = ConstantInt::getSigned(Dividend->getType(), 0);
Value *CmpV = MainBuilder.CreateICmpEQ(AndV, ZeroV);
MainBuilder.CreateCondBr(CmpV, FastBB, SlowBB);
// point iterator J at first instruction of successorBB
J = I->begin();
// Cache phi nodes to be used later in place of other instances
// of div or rem with the same sign, dividend, and divisor
DivOpInfo Key(UseSignedOp, Dividend, Divisor);
DivPhiNodes Value(QuoPhi, RemPhi);
PerBBDivCache.insert(std::pair<DivOpInfo, DivPhiNodes>(Key, Value));
return true;
}
// reuseOrInsertFastDiv - Reuses previously computed dividend or remainder if
// operands and operation are identical. Otherwise call insertFastDiv to perform
// the optimization and cache the resulting dividend and remainder.
static bool reuseOrInsertFastDiv(Function &F,
Function::iterator &I,
BasicBlock::iterator &J,
IntegerType *BypassType,
bool UseDivOp,
bool UseSignedOp,
DivCacheTy &PerBBDivCache) {
// Get instruction operands
Instruction *Instr = J;
DivOpInfo Key(UseSignedOp, Instr->getOperand(0), Instr->getOperand(1));
DivCacheTy::iterator CacheI = PerBBDivCache.find(Key);
if (CacheI == PerBBDivCache.end()) {
// If previous instance does not exist, insert fast div
return insertFastDiv(F, I, J, BypassType, UseDivOp, UseSignedOp,
PerBBDivCache);
}
// Replace operation value with previously generated phi node
DivPhiNodes &Value = CacheI->second;
if (UseDivOp) {
// Replace all uses of div instruction with quotient phi node
J->replaceAllUsesWith(Value.Quotient);
} else {
// Replace all uses of rem instruction with remainder phi node
J->replaceAllUsesWith(Value.Remainder);
}
// Advance to next operation
++J;
// Remove redundant operation
Instr->eraseFromParent();
return true;
}
// bypassSlowDivision - This optimization identifies DIV instructions that can
// be profitably bypassed and carried out with a shorter, faster divide.
bool llvm::bypassSlowDivision(Function &F,
Function::iterator &I,
const DenseMap<unsigned int, unsigned int> &BypassWidths) {
DivCacheTy DivCache;
bool MadeChange = false;
for (BasicBlock::iterator J = I->begin(); J != I->end(); J++) {
// Get instruction details
unsigned Opcode = J->getOpcode();
bool UseDivOp = Opcode == Instruction::SDiv || Opcode == Instruction::UDiv;
bool UseRemOp = Opcode == Instruction::SRem || Opcode == Instruction::URem;
bool UseSignedOp = Opcode == Instruction::SDiv ||
Opcode == Instruction::SRem;
// Only optimize div or rem ops
if (!UseDivOp && !UseRemOp)
continue;
// Skip division on vector types, only optimize integer instructions
if (!J->getType()->isIntegerTy())
continue;
// Get bitwidth of div/rem instruction
IntegerType *T = cast<IntegerType>(J->getType());
unsigned int bitwidth = T->getBitWidth();
// Continue if bitwidth is not bypassed
DenseMap<unsigned int, unsigned int>::const_iterator BI = BypassWidths.find(bitwidth);
if (BI == BypassWidths.end())
continue;
// Get type for div/rem instruction with bypass bitwidth
IntegerType *BT = IntegerType::get(J->getContext(), BI->second);
MadeChange |= reuseOrInsertFastDiv(F, I, J, BT, UseDivOp,
UseSignedOp, DivCache);
}
return MadeChange;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Utils/AddDiscriminators.cpp | //===- AddDiscriminators.cpp - Insert DWARF path discriminators -----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file adds DWARF discriminators to the IR. Path discriminators are
// used to decide what CFG path was taken inside sub-graphs whose instructions
// share the same line and column number information.
//
// The main user of this is the sample profiler. Instruction samples are
// mapped to line number information. Since a single line may be spread
// out over several basic blocks, discriminators add more precise location
// for the samples.
//
// For example,
//
// 1 #define ASSERT(P)
// 2 if (!(P))
// 3 abort()
// ...
// 100 while (true) {
// 101 ASSERT (sum < 0);
// 102 ...
// 130 }
//
// when converted to IR, this snippet looks something like:
//
// while.body: ; preds = %entry, %if.end
// %0 = load i32* %sum, align 4, !dbg !15
// %cmp = icmp slt i32 %0, 0, !dbg !15
// br i1 %cmp, label %if.end, label %if.then, !dbg !15
//
// if.then: ; preds = %while.body
// call void @abort(), !dbg !15
// br label %if.end, !dbg !15
//
// Notice that all the instructions in blocks 'while.body' and 'if.then'
// have exactly the same debug information. When this program is sampled
// at runtime, the profiler will assume that all these instructions are
// equally frequent. This, in turn, will consider the edge while.body->if.then
// to be frequently taken (which is incorrect).
//
// By adding a discriminator value to the instructions in block 'if.then',
// we can distinguish instructions at line 101 with discriminator 0 from
// the instructions at line 101 with discriminator 1.
//
// For more details about DWARF discriminators, please visit
// http://wiki.dwarfstd.org/index.php?title=Path_Discriminators
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Scalar.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DIBuilder.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
#define DEBUG_TYPE "add-discriminators"
namespace {
struct AddDiscriminators : public FunctionPass {
static char ID; // Pass identification, replacement for typeid
AddDiscriminators() : FunctionPass(ID) {
initializeAddDiscriminatorsPass(*PassRegistry::getPassRegistry());
}
bool runOnFunction(Function &F) override;
// HLSL Change Starts
bool NoDiscriminators = false;
void applyOptions(PassOptions O) override {
GetPassOptionBool(O, "no-discriminators", &NoDiscriminators, false);
}
void dumpConfig(raw_ostream &OS) override {
FunctionPass::dumpConfig(OS);
OS << ",no-discriminators=" << NoDiscriminators;
}
// HLSL Change Ends
};
}
char AddDiscriminators::ID = 0;
INITIALIZE_PASS_BEGIN(AddDiscriminators, "add-discriminators",
"Add DWARF path discriminators", false, false)
INITIALIZE_PASS_END(AddDiscriminators, "add-discriminators",
"Add DWARF path discriminators", false, false)
#ifdef HLSL_GLOBAL_OPT // HLSL Change Starts
// Command line option to disable discriminator generation even in the
// presence of debug information. This is only needed when debugging
// debug info generation issues.
static cl::opt<bool>
NoDiscriminators("no-discriminators", cl::init(false),
cl::desc("Disable generation of discriminator information."));
#endif // HLSL_GLOBAL_OPT HLSL Change Ends
FunctionPass *llvm::createAddDiscriminatorsPass() {
return new AddDiscriminators();
}
static bool hasDebugInfo(const Function &F) {
NamedMDNode *CUNodes = F.getParent()->getNamedMetadata("llvm.dbg.cu");
return CUNodes != nullptr;
}
/// \brief Assign DWARF discriminators.
///
/// To assign discriminators, we examine the boundaries of every
/// basic block and its successors. Suppose there is a basic block B1
/// with successor B2. The last instruction I1 in B1 and the first
/// instruction I2 in B2 are located at the same file and line number.
/// This situation is illustrated in the following code snippet:
///
/// if (i < 10) x = i;
///
/// entry:
/// br i1 %cmp, label %if.then, label %if.end, !dbg !10
/// if.then:
/// %1 = load i32* %i.addr, align 4, !dbg !10
/// store i32 %1, i32* %x, align 4, !dbg !10
/// br label %if.end, !dbg !10
/// if.end:
/// ret void, !dbg !12
///
/// Notice how the branch instruction in block 'entry' and all the
/// instructions in block 'if.then' have the exact same debug location
/// information (!dbg !10).
///
/// To distinguish instructions in block 'entry' from instructions in
/// block 'if.then', we generate a new lexical block for all the
/// instruction in block 'if.then' that share the same file and line
/// location with the last instruction of block 'entry'.
///
/// This new lexical block will have the same location information as
/// the previous one, but with a new DWARF discriminator value.
///
/// One of the main uses of this discriminator value is in runtime
/// sample profilers. It allows the profiler to distinguish instructions
/// at location !dbg !10 that execute on different basic blocks. This is
/// important because while the predicate 'if (x < 10)' may have been
/// executed millions of times, the assignment 'x = i' may have only
/// executed a handful of times (meaning that the entry->if.then edge is
/// seldom taken).
///
/// If we did not have discriminator information, the profiler would
/// assign the same weight to both blocks 'entry' and 'if.then', which
/// in turn will make it conclude that the entry->if.then edge is very
/// hot.
///
/// To decide where to create new discriminator values, this function
/// traverses the CFG and examines instruction at basic block boundaries.
/// If the last instruction I1 of a block B1 is at the same file and line
/// location as instruction I2 of successor B2, then it creates a new
/// lexical block for I2 and all the instruction in B2 that share the same
/// file and line location as I2. This new lexical block will have a
/// different discriminator number than I1.
bool AddDiscriminators::runOnFunction(Function &F) {
// If the function has debug information, but the user has disabled
// discriminators, do nothing.
// Simlarly, if the function has no debug info, do nothing.
// Finally, if this module is built with dwarf versions earlier than 4,
// do nothing (discriminator support is a DWARF 4 feature).
if (NoDiscriminators ||
!hasDebugInfo(F) ||
F.getParent()->getDwarfVersion() < 4)
return false;
bool Changed = false;
Module *M = F.getParent();
LLVMContext &Ctx = M->getContext();
DIBuilder Builder(*M, /*AllowUnresolved*/ false);
// Traverse all the blocks looking for instructions in different
// blocks that are at the same file:line location.
for (Function::iterator I = F.begin(), E = F.end(); I != E; ++I) {
BasicBlock *B = I;
TerminatorInst *Last = B->getTerminator();
const DILocation *LastDIL = Last->getDebugLoc();
if (!LastDIL)
continue;
for (unsigned I = 0; I < Last->getNumSuccessors(); ++I) {
BasicBlock *Succ = Last->getSuccessor(I);
Instruction *First = Succ->getFirstNonPHIOrDbgOrLifetime();
const DILocation *FirstDIL = First->getDebugLoc();
if (!FirstDIL)
continue;
// If the first instruction (First) of Succ is at the same file
// location as B's last instruction (Last), add a new
// discriminator for First's location and all the instructions
// in Succ that share the same location with First.
if (!FirstDIL->canDiscriminate(*LastDIL)) {
// Create a new lexical scope and compute a new discriminator
// number for it.
StringRef Filename = FirstDIL->getFilename();
auto *Scope = FirstDIL->getScope();
auto *File = Builder.createFile(Filename, Scope->getDirectory());
// FIXME: Calculate the discriminator here, based on local information,
// and delete DILocation::computeNewDiscriminator(). The current
// solution gives different results depending on other modules in the
// same context. All we really need is to discriminate between
// FirstDIL and LastDIL -- a local map would suffice.
unsigned Discriminator = FirstDIL->computeNewDiscriminator();
auto *NewScope =
Builder.createLexicalBlockFile(Scope, File, Discriminator);
auto *NewDIL =
DILocation::get(Ctx, FirstDIL->getLine(), FirstDIL->getColumn(),
NewScope, FirstDIL->getInlinedAt());
DebugLoc newDebugLoc = NewDIL;
// Attach this new debug location to First and every
// instruction following First that shares the same location.
for (BasicBlock::iterator I1(*First), E1 = Succ->end(); I1 != E1;
++I1) {
if (I1->getDebugLoc().get() != FirstDIL)
break;
I1->setDebugLoc(newDebugLoc);
DEBUG(dbgs() << NewDIL->getFilename() << ":" << NewDIL->getLine()
<< ":" << NewDIL->getColumn() << ":"
<< NewDIL->getDiscriminator() << *I1 << "\n");
}
DEBUG(dbgs() << "\n");
Changed = true;
}
}
}
return Changed;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Vectorize/BBVectorize.cpp | //===- BBVectorize.cpp - A Basic-Block Vectorizer -------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements a basic-block vectorization pass. The algorithm was
// inspired by that used by the Vienna MAP Vectorizor by Franchetti and Kral,
// et al. It works by looking for chains of pairable operations and then
// pairing them.
//
//===----------------------------------------------------------------------===//
#define BBV_NAME "bb-vectorize"
#include "llvm/Transforms/Vectorize.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/AliasSetTracker.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/ScalarEvolutionExpressions.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/Local.h"
#include <algorithm>
using namespace llvm;
#define DEBUG_TYPE BBV_NAME
static cl::opt<bool>
IgnoreTargetInfo("bb-vectorize-ignore-target-info", cl::init(false),
cl::Hidden, cl::desc("Ignore target information"));
static cl::opt<unsigned>
ReqChainDepth("bb-vectorize-req-chain-depth", cl::init(6), cl::Hidden,
cl::desc("The required chain depth for vectorization"));
static cl::opt<bool>
UseChainDepthWithTI("bb-vectorize-use-chain-depth", cl::init(false),
cl::Hidden, cl::desc("Use the chain depth requirement with"
" target information"));
static cl::opt<unsigned>
SearchLimit("bb-vectorize-search-limit", cl::init(400), cl::Hidden,
cl::desc("The maximum search distance for instruction pairs"));
static cl::opt<bool>
SplatBreaksChain("bb-vectorize-splat-breaks-chain", cl::init(false), cl::Hidden,
cl::desc("Replicating one element to a pair breaks the chain"));
static cl::opt<unsigned>
VectorBits("bb-vectorize-vector-bits", cl::init(128), cl::Hidden,
cl::desc("The size of the native vector registers"));
static cl::opt<unsigned>
MaxIter("bb-vectorize-max-iter", cl::init(0), cl::Hidden,
cl::desc("The maximum number of pairing iterations"));
static cl::opt<bool>
Pow2LenOnly("bb-vectorize-pow2-len-only", cl::init(false), cl::Hidden,
cl::desc("Don't try to form non-2^n-length vectors"));
static cl::opt<unsigned>
MaxInsts("bb-vectorize-max-instr-per-group", cl::init(500), cl::Hidden,
cl::desc("The maximum number of pairable instructions per group"));
static cl::opt<unsigned>
MaxPairs("bb-vectorize-max-pairs-per-group", cl::init(3000), cl::Hidden,
cl::desc("The maximum number of candidate instruction pairs per group"));
static cl::opt<unsigned>
MaxCandPairsForCycleCheck("bb-vectorize-max-cycle-check-pairs", cl::init(200),
cl::Hidden, cl::desc("The maximum number of candidate pairs with which to use"
" a full cycle check"));
static cl::opt<bool>
NoBools("bb-vectorize-no-bools", cl::init(false), cl::Hidden,
cl::desc("Don't try to vectorize boolean (i1) values"));
static cl::opt<bool>
NoInts("bb-vectorize-no-ints", cl::init(false), cl::Hidden,
cl::desc("Don't try to vectorize integer values"));
static cl::opt<bool>
NoFloats("bb-vectorize-no-floats", cl::init(false), cl::Hidden,
cl::desc("Don't try to vectorize floating-point values"));
// FIXME: This should default to false once pointer vector support works.
static cl::opt<bool>
NoPointers("bb-vectorize-no-pointers", cl::init(/*false*/ true), cl::Hidden,
cl::desc("Don't try to vectorize pointer values"));
static cl::opt<bool>
NoCasts("bb-vectorize-no-casts", cl::init(false), cl::Hidden,
cl::desc("Don't try to vectorize casting (conversion) operations"));
static cl::opt<bool>
NoMath("bb-vectorize-no-math", cl::init(false), cl::Hidden,
cl::desc("Don't try to vectorize floating-point math intrinsics"));
static cl::opt<bool>
NoBitManipulation("bb-vectorize-no-bitmanip", cl::init(false), cl::Hidden,
cl::desc("Don't try to vectorize BitManipulation intrinsics"));
static cl::opt<bool>
NoFMA("bb-vectorize-no-fma", cl::init(false), cl::Hidden,
cl::desc("Don't try to vectorize the fused-multiply-add intrinsic"));
static cl::opt<bool>
NoSelect("bb-vectorize-no-select", cl::init(false), cl::Hidden,
cl::desc("Don't try to vectorize select instructions"));
static cl::opt<bool>
NoCmp("bb-vectorize-no-cmp", cl::init(false), cl::Hidden,
cl::desc("Don't try to vectorize comparison instructions"));
static cl::opt<bool>
NoGEP("bb-vectorize-no-gep", cl::init(false), cl::Hidden,
cl::desc("Don't try to vectorize getelementptr instructions"));
static cl::opt<bool>
NoMemOps("bb-vectorize-no-mem-ops", cl::init(false), cl::Hidden,
cl::desc("Don't try to vectorize loads and stores"));
static cl::opt<bool>
AlignedOnly("bb-vectorize-aligned-only", cl::init(false), cl::Hidden,
cl::desc("Only generate aligned loads and stores"));
static cl::opt<bool>
NoMemOpBoost("bb-vectorize-no-mem-op-boost",
cl::init(false), cl::Hidden,
cl::desc("Don't boost the chain-depth contribution of loads and stores"));
static cl::opt<bool>
FastDep("bb-vectorize-fast-dep", cl::init(false), cl::Hidden,
cl::desc("Use a fast instruction dependency analysis"));
#ifndef NDEBUG
static cl::opt<bool>
DebugInstructionExamination("bb-vectorize-debug-instruction-examination",
cl::init(false), cl::Hidden,
cl::desc("When debugging is enabled, output information on the"
" instruction-examination process"));
static cl::opt<bool>
DebugCandidateSelection("bb-vectorize-debug-candidate-selection",
cl::init(false), cl::Hidden,
cl::desc("When debugging is enabled, output information on the"
" candidate-selection process"));
static cl::opt<bool>
DebugPairSelection("bb-vectorize-debug-pair-selection",
cl::init(false), cl::Hidden,
cl::desc("When debugging is enabled, output information on the"
" pair-selection process"));
static cl::opt<bool>
DebugCycleCheck("bb-vectorize-debug-cycle-check",
cl::init(false), cl::Hidden,
cl::desc("When debugging is enabled, output information on the"
" cycle-checking process"));
static cl::opt<bool>
PrintAfterEveryPair("bb-vectorize-debug-print-after-every-pair",
cl::init(false), cl::Hidden,
cl::desc("When debugging is enabled, dump the basic block after"
" every pair is fused"));
#endif
STATISTIC(NumFusedOps, "Number of operations fused by bb-vectorize");
namespace {
struct BBVectorize : public BasicBlockPass {
static char ID; // Pass identification, replacement for typeid
const VectorizeConfig Config;
BBVectorize(const VectorizeConfig &C = VectorizeConfig())
: BasicBlockPass(ID), Config(C) {
initializeBBVectorizePass(*PassRegistry::getPassRegistry());
}
BBVectorize(Pass *P, Function &F, const VectorizeConfig &C)
: BasicBlockPass(ID), Config(C) {
AA = &P->getAnalysis<AliasAnalysis>();
DT = &P->getAnalysis<DominatorTreeWrapperPass>().getDomTree();
SE = &P->getAnalysis<ScalarEvolution>();
TTI = IgnoreTargetInfo
? nullptr
: &P->getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
}
typedef std::pair<Value *, Value *> ValuePair;
typedef std::pair<ValuePair, int> ValuePairWithCost;
typedef std::pair<ValuePair, size_t> ValuePairWithDepth;
typedef std::pair<ValuePair, ValuePair> VPPair; // A ValuePair pair
typedef std::pair<VPPair, unsigned> VPPairWithType;
AliasAnalysis *AA;
DominatorTree *DT;
ScalarEvolution *SE;
const TargetTransformInfo *TTI;
// FIXME: const correct?
bool vectorizePairs(BasicBlock &BB, bool NonPow2Len = false);
bool getCandidatePairs(BasicBlock &BB,
BasicBlock::iterator &Start,
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
DenseSet<ValuePair> &FixedOrderPairs,
DenseMap<ValuePair, int> &CandidatePairCostSavings,
std::vector<Value *> &PairableInsts, bool NonPow2Len);
// FIXME: The current implementation does not account for pairs that
// are connected in multiple ways. For example:
// C1 = A1 / A2; C2 = A2 / A1 (which may be both direct and a swap)
enum PairConnectionType {
PairConnectionDirect,
PairConnectionSwap,
PairConnectionSplat
};
void computeConnectedPairs(
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
DenseSet<ValuePair> &CandidatePairsSet,
std::vector<Value *> &PairableInsts,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
DenseMap<VPPair, unsigned> &PairConnectionTypes);
void buildDepMap(BasicBlock &BB,
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
std::vector<Value *> &PairableInsts,
DenseSet<ValuePair> &PairableInstUsers);
void choosePairs(DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
DenseSet<ValuePair> &CandidatePairsSet,
DenseMap<ValuePair, int> &CandidatePairCostSavings,
std::vector<Value *> &PairableInsts,
DenseSet<ValuePair> &FixedOrderPairs,
DenseMap<VPPair, unsigned> &PairConnectionTypes,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps,
DenseSet<ValuePair> &PairableInstUsers,
DenseMap<Value *, Value *>& ChosenPairs);
void fuseChosenPairs(BasicBlock &BB,
std::vector<Value *> &PairableInsts,
DenseMap<Value *, Value *>& ChosenPairs,
DenseSet<ValuePair> &FixedOrderPairs,
DenseMap<VPPair, unsigned> &PairConnectionTypes,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps);
bool isInstVectorizable(Instruction *I, bool &IsSimpleLoadStore);
bool areInstsCompatible(Instruction *I, Instruction *J,
bool IsSimpleLoadStore, bool NonPow2Len,
int &CostSavings, int &FixedOrder);
bool trackUsesOfI(DenseSet<Value *> &Users,
AliasSetTracker &WriteSet, Instruction *I,
Instruction *J, bool UpdateUsers = true,
DenseSet<ValuePair> *LoadMoveSetPairs = nullptr);
void computePairsConnectedTo(
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
DenseSet<ValuePair> &CandidatePairsSet,
std::vector<Value *> &PairableInsts,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
DenseMap<VPPair, unsigned> &PairConnectionTypes,
ValuePair P);
bool pairsConflict(ValuePair P, ValuePair Q,
DenseSet<ValuePair> &PairableInstUsers,
DenseMap<ValuePair, std::vector<ValuePair> >
*PairableInstUserMap = nullptr,
DenseSet<VPPair> *PairableInstUserPairSet = nullptr);
bool pairWillFormCycle(ValuePair P,
DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUsers,
DenseSet<ValuePair> &CurrentPairs);
void pruneDAGFor(
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
std::vector<Value *> &PairableInsts,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
DenseSet<ValuePair> &PairableInstUsers,
DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap,
DenseSet<VPPair> &PairableInstUserPairSet,
DenseMap<Value *, Value *> &ChosenPairs,
DenseMap<ValuePair, size_t> &DAG,
DenseSet<ValuePair> &PrunedDAG, ValuePair J,
bool UseCycleCheck);
void buildInitialDAGFor(
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
DenseSet<ValuePair> &CandidatePairsSet,
std::vector<Value *> &PairableInsts,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
DenseSet<ValuePair> &PairableInstUsers,
DenseMap<Value *, Value *> &ChosenPairs,
DenseMap<ValuePair, size_t> &DAG, ValuePair J);
void findBestDAGFor(
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
DenseSet<ValuePair> &CandidatePairsSet,
DenseMap<ValuePair, int> &CandidatePairCostSavings,
std::vector<Value *> &PairableInsts,
DenseSet<ValuePair> &FixedOrderPairs,
DenseMap<VPPair, unsigned> &PairConnectionTypes,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps,
DenseSet<ValuePair> &PairableInstUsers,
DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap,
DenseSet<VPPair> &PairableInstUserPairSet,
DenseMap<Value *, Value *> &ChosenPairs,
DenseSet<ValuePair> &BestDAG, size_t &BestMaxDepth,
int &BestEffSize, Value *II, std::vector<Value *>&JJ,
bool UseCycleCheck);
Value *getReplacementPointerInput(LLVMContext& Context, Instruction *I,
Instruction *J, unsigned o);
void fillNewShuffleMask(LLVMContext& Context, Instruction *J,
unsigned MaskOffset, unsigned NumInElem,
unsigned NumInElem1, unsigned IdxOffset,
std::vector<Constant*> &Mask);
Value *getReplacementShuffleMask(LLVMContext& Context, Instruction *I,
Instruction *J);
bool expandIEChain(LLVMContext& Context, Instruction *I, Instruction *J,
unsigned o, Value *&LOp, unsigned numElemL,
Type *ArgTypeL, Type *ArgTypeR, bool IBeforeJ,
unsigned IdxOff = 0);
Value *getReplacementInput(LLVMContext& Context, Instruction *I,
Instruction *J, unsigned o, bool IBeforeJ);
void getReplacementInputsForPair(LLVMContext& Context, Instruction *I,
Instruction *J, SmallVectorImpl<Value *> &ReplacedOperands,
bool IBeforeJ);
void replaceOutputsOfPair(LLVMContext& Context, Instruction *I,
Instruction *J, Instruction *K,
Instruction *&InsertionPt, Instruction *&K1,
Instruction *&K2);
void collectPairLoadMoveSet(BasicBlock &BB,
DenseMap<Value *, Value *> &ChosenPairs,
DenseMap<Value *, std::vector<Value *> > &LoadMoveSet,
DenseSet<ValuePair> &LoadMoveSetPairs,
Instruction *I);
void collectLoadMoveSet(BasicBlock &BB,
std::vector<Value *> &PairableInsts,
DenseMap<Value *, Value *> &ChosenPairs,
DenseMap<Value *, std::vector<Value *> > &LoadMoveSet,
DenseSet<ValuePair> &LoadMoveSetPairs);
bool canMoveUsesOfIAfterJ(BasicBlock &BB,
DenseSet<ValuePair> &LoadMoveSetPairs,
Instruction *I, Instruction *J);
void moveUsesOfIAfterJ(BasicBlock &BB,
DenseSet<ValuePair> &LoadMoveSetPairs,
Instruction *&InsertionPt,
Instruction *I, Instruction *J);
bool vectorizeBB(BasicBlock &BB) {
if (skipOptnoneFunction(BB))
return false;
if (!DT->isReachableFromEntry(&BB)) {
DEBUG(dbgs() << "BBV: skipping unreachable " << BB.getName() <<
" in " << BB.getParent()->getName() << "\n");
return false;
}
DEBUG(if (TTI) dbgs() << "BBV: using target information\n");
bool changed = false;
// Iterate a sufficient number of times to merge types of size 1 bit,
// then 2 bits, then 4, etc. up to half of the target vector width of the
// target vector register.
unsigned n = 1;
for (unsigned v = 2;
(TTI || v <= Config.VectorBits) &&
(!Config.MaxIter || n <= Config.MaxIter);
v *= 2, ++n) {
DEBUG(dbgs() << "BBV: fusing loop #" << n <<
" for " << BB.getName() << " in " <<
BB.getParent()->getName() << "...\n");
if (vectorizePairs(BB))
changed = true;
else
break;
}
if (changed && !Pow2LenOnly) {
++n;
for (; !Config.MaxIter || n <= Config.MaxIter; ++n) {
DEBUG(dbgs() << "BBV: fusing for non-2^n-length vectors loop #: " <<
n << " for " << BB.getName() << " in " <<
BB.getParent()->getName() << "...\n");
if (!vectorizePairs(BB, true)) break;
}
}
DEBUG(dbgs() << "BBV: done!\n");
return changed;
}
bool runOnBasicBlock(BasicBlock &BB) override {
// OptimizeNone check deferred to vectorizeBB().
AA = &getAnalysis<AliasAnalysis>();
DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
SE = &getAnalysis<ScalarEvolution>();
TTI = IgnoreTargetInfo
? nullptr
: &getAnalysis<TargetTransformInfoWrapperPass>().getTTI(
*BB.getParent());
return vectorizeBB(BB);
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
BasicBlockPass::getAnalysisUsage(AU);
AU.addRequired<AliasAnalysis>();
AU.addRequired<DominatorTreeWrapperPass>();
AU.addRequired<ScalarEvolution>();
AU.addRequired<TargetTransformInfoWrapperPass>();
AU.addPreserved<AliasAnalysis>();
AU.addPreserved<DominatorTreeWrapperPass>();
AU.addPreserved<ScalarEvolution>();
AU.setPreservesCFG();
}
static inline VectorType *getVecTypeForPair(Type *ElemTy, Type *Elem2Ty) {
assert(ElemTy->getScalarType() == Elem2Ty->getScalarType() &&
"Cannot form vector from incompatible scalar types");
Type *STy = ElemTy->getScalarType();
unsigned numElem;
if (VectorType *VTy = dyn_cast<VectorType>(ElemTy)) {
numElem = VTy->getNumElements();
} else {
numElem = 1;
}
if (VectorType *VTy = dyn_cast<VectorType>(Elem2Ty)) {
numElem += VTy->getNumElements();
} else {
numElem += 1;
}
return VectorType::get(STy, numElem);
}
static inline void getInstructionTypes(Instruction *I,
Type *&T1, Type *&T2) {
if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
// For stores, it is the value type, not the pointer type that matters
// because the value is what will come from a vector register.
Value *IVal = SI->getValueOperand();
T1 = IVal->getType();
} else {
T1 = I->getType();
}
if (CastInst *CI = dyn_cast<CastInst>(I))
T2 = CI->getSrcTy();
else
T2 = T1;
if (SelectInst *SI = dyn_cast<SelectInst>(I)) {
T2 = SI->getCondition()->getType();
} else if (ShuffleVectorInst *SI = dyn_cast<ShuffleVectorInst>(I)) {
T2 = SI->getOperand(0)->getType();
} else if (CmpInst *CI = dyn_cast<CmpInst>(I)) {
T2 = CI->getOperand(0)->getType();
}
}
// Returns the weight associated with the provided value. A chain of
// candidate pairs has a length given by the sum of the weights of its
// members (one weight per pair; the weight of each member of the pair
// is assumed to be the same). This length is then compared to the
// chain-length threshold to determine if a given chain is significant
// enough to be vectorized. The length is also used in comparing
// candidate chains where longer chains are considered to be better.
// Note: when this function returns 0, the resulting instructions are
// not actually fused.
inline size_t getDepthFactor(Value *V) {
// InsertElement and ExtractElement have a depth factor of zero. This is
// for two reasons: First, they cannot be usefully fused. Second, because
// the pass generates a lot of these, they can confuse the simple metric
// used to compare the dags in the next iteration. Thus, giving them a
// weight of zero allows the pass to essentially ignore them in
// subsequent iterations when looking for vectorization opportunities
// while still tracking dependency chains that flow through those
// instructions.
if (isa<InsertElementInst>(V) || isa<ExtractElementInst>(V))
return 0;
// Give a load or store half of the required depth so that load/store
// pairs will vectorize.
if (!Config.NoMemOpBoost && (isa<LoadInst>(V) || isa<StoreInst>(V)))
return Config.ReqChainDepth/2;
return 1;
}
// Returns the cost of the provided instruction using TTI.
// This does not handle loads and stores.
unsigned getInstrCost(unsigned Opcode, Type *T1, Type *T2,
TargetTransformInfo::OperandValueKind Op1VK =
TargetTransformInfo::OK_AnyValue,
TargetTransformInfo::OperandValueKind Op2VK =
TargetTransformInfo::OK_AnyValue) {
switch (Opcode) {
default: break;
case Instruction::GetElementPtr:
// We mark this instruction as zero-cost because scalar GEPs are usually
// lowered to the instruction addressing mode. At the moment we don't
// generate vector GEPs.
return 0;
case Instruction::Br:
return TTI->getCFInstrCost(Opcode);
case Instruction::PHI:
return 0;
case Instruction::Add:
case Instruction::FAdd:
case Instruction::Sub:
case Instruction::FSub:
case Instruction::Mul:
case Instruction::FMul:
case Instruction::UDiv:
case Instruction::SDiv:
case Instruction::FDiv:
case Instruction::URem:
case Instruction::SRem:
case Instruction::FRem:
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor:
return TTI->getArithmeticInstrCost(Opcode, T1, Op1VK, Op2VK);
case Instruction::Select:
case Instruction::ICmp:
case Instruction::FCmp:
return TTI->getCmpSelInstrCost(Opcode, T1, T2);
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::FPToUI:
case Instruction::FPToSI:
case Instruction::FPExt:
case Instruction::PtrToInt:
case Instruction::IntToPtr:
case Instruction::SIToFP:
case Instruction::UIToFP:
case Instruction::Trunc:
case Instruction::FPTrunc:
case Instruction::BitCast:
case Instruction::ShuffleVector:
return TTI->getCastInstrCost(Opcode, T1, T2);
}
return 1;
}
// This determines the relative offset of two loads or stores, returning
// true if the offset could be determined to be some constant value.
// For example, if OffsetInElmts == 1, then J accesses the memory directly
// after I; if OffsetInElmts == -1 then I accesses the memory
// directly after J.
bool getPairPtrInfo(Instruction *I, Instruction *J,
Value *&IPtr, Value *&JPtr, unsigned &IAlignment, unsigned &JAlignment,
unsigned &IAddressSpace, unsigned &JAddressSpace,
int64_t &OffsetInElmts, bool ComputeOffset = true) {
OffsetInElmts = 0;
if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
LoadInst *LJ = cast<LoadInst>(J);
IPtr = LI->getPointerOperand();
JPtr = LJ->getPointerOperand();
IAlignment = LI->getAlignment();
JAlignment = LJ->getAlignment();
IAddressSpace = LI->getPointerAddressSpace();
JAddressSpace = LJ->getPointerAddressSpace();
} else {
StoreInst *SI = cast<StoreInst>(I), *SJ = cast<StoreInst>(J);
IPtr = SI->getPointerOperand();
JPtr = SJ->getPointerOperand();
IAlignment = SI->getAlignment();
JAlignment = SJ->getAlignment();
IAddressSpace = SI->getPointerAddressSpace();
JAddressSpace = SJ->getPointerAddressSpace();
}
if (!ComputeOffset)
return true;
const SCEV *IPtrSCEV = SE->getSCEV(IPtr);
const SCEV *JPtrSCEV = SE->getSCEV(JPtr);
// If this is a trivial offset, then we'll get something like
// 1*sizeof(type). With target data, which we need anyway, this will get
// constant folded into a number.
const SCEV *OffsetSCEV = SE->getMinusSCEV(JPtrSCEV, IPtrSCEV);
if (const SCEVConstant *ConstOffSCEV =
dyn_cast<SCEVConstant>(OffsetSCEV)) {
ConstantInt *IntOff = ConstOffSCEV->getValue();
int64_t Offset = IntOff->getSExtValue();
const DataLayout &DL = I->getModule()->getDataLayout();
Type *VTy = IPtr->getType()->getPointerElementType();
int64_t VTyTSS = (int64_t)DL.getTypeStoreSize(VTy);
Type *VTy2 = JPtr->getType()->getPointerElementType();
if (VTy != VTy2 && Offset < 0) {
int64_t VTy2TSS = (int64_t)DL.getTypeStoreSize(VTy2);
OffsetInElmts = Offset/VTy2TSS;
return (std::abs(Offset) % VTy2TSS) == 0;
}
OffsetInElmts = Offset/VTyTSS;
return (std::abs(Offset) % VTyTSS) == 0;
}
return false;
}
// Returns true if the provided CallInst represents an intrinsic that can
// be vectorized.
bool isVectorizableIntrinsic(CallInst* I) {
Function *F = I->getCalledFunction();
if (!F) return false;
Intrinsic::ID IID = F->getIntrinsicID();
if (!IID) return false;
switch(IID) {
default:
return false;
case Intrinsic::sqrt:
case Intrinsic::powi:
case Intrinsic::sin:
case Intrinsic::cos:
case Intrinsic::log:
case Intrinsic::log2:
case Intrinsic::log10:
case Intrinsic::exp:
case Intrinsic::exp2:
case Intrinsic::pow:
case Intrinsic::round:
case Intrinsic::copysign:
case Intrinsic::ceil:
case Intrinsic::nearbyint:
case Intrinsic::rint:
case Intrinsic::trunc:
case Intrinsic::floor:
case Intrinsic::fabs:
case Intrinsic::minnum:
case Intrinsic::maxnum:
return Config.VectorizeMath;
case Intrinsic::bswap:
case Intrinsic::ctpop:
case Intrinsic::ctlz:
case Intrinsic::cttz:
return Config.VectorizeBitManipulations;
case Intrinsic::fma:
case Intrinsic::fmuladd:
return Config.VectorizeFMA;
}
}
bool isPureIEChain(InsertElementInst *IE) {
InsertElementInst *IENext = IE;
do {
if (!isa<UndefValue>(IENext->getOperand(0)) &&
!isa<InsertElementInst>(IENext->getOperand(0))) {
return false;
}
} while ((IENext =
dyn_cast<InsertElementInst>(IENext->getOperand(0))));
return true;
}
};
// This function implements one vectorization iteration on the provided
// basic block. It returns true if the block is changed.
bool BBVectorize::vectorizePairs(BasicBlock &BB, bool NonPow2Len) {
bool ShouldContinue;
BasicBlock::iterator Start = BB.getFirstInsertionPt();
std::vector<Value *> AllPairableInsts;
DenseMap<Value *, Value *> AllChosenPairs;
DenseSet<ValuePair> AllFixedOrderPairs;
DenseMap<VPPair, unsigned> AllPairConnectionTypes;
DenseMap<ValuePair, std::vector<ValuePair> > AllConnectedPairs,
AllConnectedPairDeps;
do {
std::vector<Value *> PairableInsts;
DenseMap<Value *, std::vector<Value *> > CandidatePairs;
DenseSet<ValuePair> FixedOrderPairs;
DenseMap<ValuePair, int> CandidatePairCostSavings;
ShouldContinue = getCandidatePairs(BB, Start, CandidatePairs,
FixedOrderPairs,
CandidatePairCostSavings,
PairableInsts, NonPow2Len);
if (PairableInsts.empty()) continue;
// Build the candidate pair set for faster lookups.
DenseSet<ValuePair> CandidatePairsSet;
for (DenseMap<Value *, std::vector<Value *> >::iterator I =
CandidatePairs.begin(), E = CandidatePairs.end(); I != E; ++I)
for (std::vector<Value *>::iterator J = I->second.begin(),
JE = I->second.end(); J != JE; ++J)
CandidatePairsSet.insert(ValuePair(I->first, *J));
// Now we have a map of all of the pairable instructions and we need to
// select the best possible pairing. A good pairing is one such that the
// users of the pair are also paired. This defines a (directed) forest
// over the pairs such that two pairs are connected iff the second pair
// uses the first.
// Note that it only matters that both members of the second pair use some
// element of the first pair (to allow for splatting).
DenseMap<ValuePair, std::vector<ValuePair> > ConnectedPairs,
ConnectedPairDeps;
DenseMap<VPPair, unsigned> PairConnectionTypes;
computeConnectedPairs(CandidatePairs, CandidatePairsSet,
PairableInsts, ConnectedPairs, PairConnectionTypes);
if (ConnectedPairs.empty()) continue;
for (DenseMap<ValuePair, std::vector<ValuePair> >::iterator
I = ConnectedPairs.begin(), IE = ConnectedPairs.end();
I != IE; ++I)
for (std::vector<ValuePair>::iterator J = I->second.begin(),
JE = I->second.end(); J != JE; ++J)
ConnectedPairDeps[*J].push_back(I->first);
// Build the pairable-instruction dependency map
DenseSet<ValuePair> PairableInstUsers;
buildDepMap(BB, CandidatePairs, PairableInsts, PairableInstUsers);
// There is now a graph of the connected pairs. For each variable, pick
// the pairing with the largest dag meeting the depth requirement on at
// least one branch. Then select all pairings that are part of that dag
// and remove them from the list of available pairings and pairable
// variables.
DenseMap<Value *, Value *> ChosenPairs;
choosePairs(CandidatePairs, CandidatePairsSet,
CandidatePairCostSavings,
PairableInsts, FixedOrderPairs, PairConnectionTypes,
ConnectedPairs, ConnectedPairDeps,
PairableInstUsers, ChosenPairs);
if (ChosenPairs.empty()) continue;
AllPairableInsts.insert(AllPairableInsts.end(), PairableInsts.begin(),
PairableInsts.end());
AllChosenPairs.insert(ChosenPairs.begin(), ChosenPairs.end());
// Only for the chosen pairs, propagate information on fixed-order pairs,
// pair connections, and their types to the data structures used by the
// pair fusion procedures.
for (DenseMap<Value *, Value *>::iterator I = ChosenPairs.begin(),
IE = ChosenPairs.end(); I != IE; ++I) {
if (FixedOrderPairs.count(*I))
AllFixedOrderPairs.insert(*I);
else if (FixedOrderPairs.count(ValuePair(I->second, I->first)))
AllFixedOrderPairs.insert(ValuePair(I->second, I->first));
for (DenseMap<Value *, Value *>::iterator J = ChosenPairs.begin();
J != IE; ++J) {
DenseMap<VPPair, unsigned>::iterator K =
PairConnectionTypes.find(VPPair(*I, *J));
if (K != PairConnectionTypes.end()) {
AllPairConnectionTypes.insert(*K);
} else {
K = PairConnectionTypes.find(VPPair(*J, *I));
if (K != PairConnectionTypes.end())
AllPairConnectionTypes.insert(*K);
}
}
}
for (DenseMap<ValuePair, std::vector<ValuePair> >::iterator
I = ConnectedPairs.begin(), IE = ConnectedPairs.end();
I != IE; ++I)
for (std::vector<ValuePair>::iterator J = I->second.begin(),
JE = I->second.end(); J != JE; ++J)
if (AllPairConnectionTypes.count(VPPair(I->first, *J))) {
AllConnectedPairs[I->first].push_back(*J);
AllConnectedPairDeps[*J].push_back(I->first);
}
} while (ShouldContinue);
if (AllChosenPairs.empty()) return false;
NumFusedOps += AllChosenPairs.size();
// A set of pairs has now been selected. It is now necessary to replace the
// paired instructions with vector instructions. For this procedure each
// operand must be replaced with a vector operand. This vector is formed
// by using build_vector on the old operands. The replaced values are then
// replaced with a vector_extract on the result. Subsequent optimization
// passes should coalesce the build/extract combinations.
fuseChosenPairs(BB, AllPairableInsts, AllChosenPairs, AllFixedOrderPairs,
AllPairConnectionTypes,
AllConnectedPairs, AllConnectedPairDeps);
// It is important to cleanup here so that future iterations of this
// function have less work to do.
(void)SimplifyInstructionsInBlock(&BB, AA->getTargetLibraryInfo());
return true;
}
// This function returns true if the provided instruction is capable of being
// fused into a vector instruction. This determination is based only on the
// type and other attributes of the instruction.
bool BBVectorize::isInstVectorizable(Instruction *I,
bool &IsSimpleLoadStore) {
IsSimpleLoadStore = false;
if (CallInst *C = dyn_cast<CallInst>(I)) {
if (!isVectorizableIntrinsic(C))
return false;
} else if (LoadInst *L = dyn_cast<LoadInst>(I)) {
// Vectorize simple loads if possbile:
IsSimpleLoadStore = L->isSimple();
if (!IsSimpleLoadStore || !Config.VectorizeMemOps)
return false;
} else if (StoreInst *S = dyn_cast<StoreInst>(I)) {
// Vectorize simple stores if possbile:
IsSimpleLoadStore = S->isSimple();
if (!IsSimpleLoadStore || !Config.VectorizeMemOps)
return false;
} else if (CastInst *C = dyn_cast<CastInst>(I)) {
// We can vectorize casts, but not casts of pointer types, etc.
if (!Config.VectorizeCasts)
return false;
Type *SrcTy = C->getSrcTy();
if (!SrcTy->isSingleValueType())
return false;
Type *DestTy = C->getDestTy();
if (!DestTy->isSingleValueType())
return false;
} else if (isa<SelectInst>(I)) {
if (!Config.VectorizeSelect)
return false;
} else if (isa<CmpInst>(I)) {
if (!Config.VectorizeCmp)
return false;
} else if (GetElementPtrInst *G = dyn_cast<GetElementPtrInst>(I)) {
if (!Config.VectorizeGEP)
return false;
// Currently, vector GEPs exist only with one index.
if (G->getNumIndices() != 1)
return false;
} else if (!(I->isBinaryOp() || isa<ShuffleVectorInst>(I) ||
isa<ExtractElementInst>(I) || isa<InsertElementInst>(I))) {
return false;
}
Type *T1, *T2;
getInstructionTypes(I, T1, T2);
// Not every type can be vectorized...
if (!(VectorType::isValidElementType(T1) || T1->isVectorTy()) ||
!(VectorType::isValidElementType(T2) || T2->isVectorTy()))
return false;
if (T1->getScalarSizeInBits() == 1) {
if (!Config.VectorizeBools)
return false;
} else {
if (!Config.VectorizeInts && T1->isIntOrIntVectorTy())
return false;
}
if (T2->getScalarSizeInBits() == 1) {
if (!Config.VectorizeBools)
return false;
} else {
if (!Config.VectorizeInts && T2->isIntOrIntVectorTy())
return false;
}
if (!Config.VectorizeFloats
&& (T1->isFPOrFPVectorTy() || T2->isFPOrFPVectorTy()))
return false;
// Don't vectorize target-specific types.
if (T1->isX86_FP80Ty() || T1->isPPC_FP128Ty() || T1->isX86_MMXTy())
return false;
if (T2->isX86_FP80Ty() || T2->isPPC_FP128Ty() || T2->isX86_MMXTy())
return false;
if (!Config.VectorizePointers && (T1->getScalarType()->isPointerTy() ||
T2->getScalarType()->isPointerTy()))
return false;
if (!TTI && (T1->getPrimitiveSizeInBits() >= Config.VectorBits ||
T2->getPrimitiveSizeInBits() >= Config.VectorBits))
return false;
return true;
}
// This function returns true if the two provided instructions are compatible
// (meaning that they can be fused into a vector instruction). This assumes
// that I has already been determined to be vectorizable and that J is not
// in the use dag of I.
bool BBVectorize::areInstsCompatible(Instruction *I, Instruction *J,
bool IsSimpleLoadStore, bool NonPow2Len,
int &CostSavings, int &FixedOrder) {
DEBUG(if (DebugInstructionExamination) dbgs() << "BBV: looking at " << *I <<
" <-> " << *J << "\n");
CostSavings = 0;
FixedOrder = 0;
// Loads and stores can be merged if they have different alignments,
// but are otherwise the same.
if (!J->isSameOperationAs(I, Instruction::CompareIgnoringAlignment |
(NonPow2Len ? Instruction::CompareUsingScalarTypes : 0)))
return false;
Type *IT1, *IT2, *JT1, *JT2;
getInstructionTypes(I, IT1, IT2);
getInstructionTypes(J, JT1, JT2);
unsigned MaxTypeBits = std::max(
IT1->getPrimitiveSizeInBits() + JT1->getPrimitiveSizeInBits(),
IT2->getPrimitiveSizeInBits() + JT2->getPrimitiveSizeInBits());
if (!TTI && MaxTypeBits > Config.VectorBits)
return false;
// FIXME: handle addsub-type operations!
if (IsSimpleLoadStore) {
Value *IPtr, *JPtr;
unsigned IAlignment, JAlignment, IAddressSpace, JAddressSpace;
int64_t OffsetInElmts = 0;
if (getPairPtrInfo(I, J, IPtr, JPtr, IAlignment, JAlignment,
IAddressSpace, JAddressSpace, OffsetInElmts) &&
std::abs(OffsetInElmts) == 1) {
FixedOrder = (int) OffsetInElmts;
unsigned BottomAlignment = IAlignment;
if (OffsetInElmts < 0) BottomAlignment = JAlignment;
Type *aTypeI = isa<StoreInst>(I) ?
cast<StoreInst>(I)->getValueOperand()->getType() : I->getType();
Type *aTypeJ = isa<StoreInst>(J) ?
cast<StoreInst>(J)->getValueOperand()->getType() : J->getType();
Type *VType = getVecTypeForPair(aTypeI, aTypeJ);
if (Config.AlignedOnly) {
// An aligned load or store is possible only if the instruction
// with the lower offset has an alignment suitable for the
// vector type.
const DataLayout &DL = I->getModule()->getDataLayout();
unsigned VecAlignment = DL.getPrefTypeAlignment(VType);
if (BottomAlignment < VecAlignment)
return false;
}
if (TTI) {
unsigned ICost = TTI->getMemoryOpCost(I->getOpcode(), aTypeI,
IAlignment, IAddressSpace);
unsigned JCost = TTI->getMemoryOpCost(J->getOpcode(), aTypeJ,
JAlignment, JAddressSpace);
unsigned VCost = TTI->getMemoryOpCost(I->getOpcode(), VType,
BottomAlignment,
IAddressSpace);
ICost += TTI->getAddressComputationCost(aTypeI);
JCost += TTI->getAddressComputationCost(aTypeJ);
VCost += TTI->getAddressComputationCost(VType);
if (VCost > ICost + JCost)
return false;
// We don't want to fuse to a type that will be split, even
// if the two input types will also be split and there is no other
// associated cost.
unsigned VParts = TTI->getNumberOfParts(VType);
if (VParts > 1)
return false;
else if (!VParts && VCost == ICost + JCost)
return false;
CostSavings = ICost + JCost - VCost;
}
} else {
return false;
}
} else if (TTI) {
unsigned ICost = getInstrCost(I->getOpcode(), IT1, IT2);
unsigned JCost = getInstrCost(J->getOpcode(), JT1, JT2);
Type *VT1 = getVecTypeForPair(IT1, JT1),
*VT2 = getVecTypeForPair(IT2, JT2);
TargetTransformInfo::OperandValueKind Op1VK =
TargetTransformInfo::OK_AnyValue;
TargetTransformInfo::OperandValueKind Op2VK =
TargetTransformInfo::OK_AnyValue;
// On some targets (example X86) the cost of a vector shift may vary
// depending on whether the second operand is a Uniform or
// NonUniform Constant.
switch (I->getOpcode()) {
default : break;
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
// If both I and J are scalar shifts by constant, then the
// merged vector shift count would be either a constant splat value
// or a non-uniform vector of constants.
if (ConstantInt *CII = dyn_cast<ConstantInt>(I->getOperand(1))) {
if (ConstantInt *CIJ = dyn_cast<ConstantInt>(J->getOperand(1)))
Op2VK = CII == CIJ ? TargetTransformInfo::OK_UniformConstantValue :
TargetTransformInfo::OK_NonUniformConstantValue;
} else {
// Check for a splat of a constant or for a non uniform vector
// of constants.
Value *IOp = I->getOperand(1);
Value *JOp = J->getOperand(1);
if ((isa<ConstantVector>(IOp) || isa<ConstantDataVector>(IOp)) &&
(isa<ConstantVector>(JOp) || isa<ConstantDataVector>(JOp))) {
Op2VK = TargetTransformInfo::OK_NonUniformConstantValue;
Constant *SplatValue = cast<Constant>(IOp)->getSplatValue();
if (SplatValue != nullptr &&
SplatValue == cast<Constant>(JOp)->getSplatValue())
Op2VK = TargetTransformInfo::OK_UniformConstantValue;
}
}
}
// Note that this procedure is incorrect for insert and extract element
// instructions (because combining these often results in a shuffle),
// but this cost is ignored (because insert and extract element
// instructions are assigned a zero depth factor and are not really
// fused in general).
unsigned VCost = getInstrCost(I->getOpcode(), VT1, VT2, Op1VK, Op2VK);
if (VCost > ICost + JCost)
return false;
// We don't want to fuse to a type that will be split, even
// if the two input types will also be split and there is no other
// associated cost.
unsigned VParts1 = TTI->getNumberOfParts(VT1),
VParts2 = TTI->getNumberOfParts(VT2);
if (VParts1 > 1 || VParts2 > 1)
return false;
else if ((!VParts1 || !VParts2) && VCost == ICost + JCost)
return false;
CostSavings = ICost + JCost - VCost;
}
// The powi,ctlz,cttz intrinsics are special because only the first
// argument is vectorized, the second arguments must be equal.
CallInst *CI = dyn_cast<CallInst>(I);
Function *FI;
if (CI && (FI = CI->getCalledFunction())) {
Intrinsic::ID IID = FI->getIntrinsicID();
if (IID == Intrinsic::powi || IID == Intrinsic::ctlz ||
IID == Intrinsic::cttz) {
Value *A1I = CI->getArgOperand(1),
*A1J = cast<CallInst>(J)->getArgOperand(1);
const SCEV *A1ISCEV = SE->getSCEV(A1I),
*A1JSCEV = SE->getSCEV(A1J);
return (A1ISCEV == A1JSCEV);
}
if (IID && TTI) {
SmallVector<Type*, 4> Tys;
for (unsigned i = 0, ie = CI->getNumArgOperands(); i != ie; ++i)
Tys.push_back(CI->getArgOperand(i)->getType());
unsigned ICost = TTI->getIntrinsicInstrCost(IID, IT1, Tys);
Tys.clear();
CallInst *CJ = cast<CallInst>(J);
for (unsigned i = 0, ie = CJ->getNumArgOperands(); i != ie; ++i)
Tys.push_back(CJ->getArgOperand(i)->getType());
unsigned JCost = TTI->getIntrinsicInstrCost(IID, JT1, Tys);
Tys.clear();
assert(CI->getNumArgOperands() == CJ->getNumArgOperands() &&
"Intrinsic argument counts differ");
for (unsigned i = 0, ie = CI->getNumArgOperands(); i != ie; ++i) {
if ((IID == Intrinsic::powi || IID == Intrinsic::ctlz ||
IID == Intrinsic::cttz) && i == 1)
Tys.push_back(CI->getArgOperand(i)->getType());
else
Tys.push_back(getVecTypeForPair(CI->getArgOperand(i)->getType(),
CJ->getArgOperand(i)->getType()));
}
Type *RetTy = getVecTypeForPair(IT1, JT1);
unsigned VCost = TTI->getIntrinsicInstrCost(IID, RetTy, Tys);
if (VCost > ICost + JCost)
return false;
// We don't want to fuse to a type that will be split, even
// if the two input types will also be split and there is no other
// associated cost.
unsigned RetParts = TTI->getNumberOfParts(RetTy);
if (RetParts > 1)
return false;
else if (!RetParts && VCost == ICost + JCost)
return false;
for (unsigned i = 0, ie = CI->getNumArgOperands(); i != ie; ++i) {
if (!Tys[i]->isVectorTy())
continue;
unsigned NumParts = TTI->getNumberOfParts(Tys[i]);
if (NumParts > 1)
return false;
else if (!NumParts && VCost == ICost + JCost)
return false;
}
CostSavings = ICost + JCost - VCost;
}
}
return true;
}
// Figure out whether or not J uses I and update the users and write-set
// structures associated with I. Specifically, Users represents the set of
// instructions that depend on I. WriteSet represents the set
// of memory locations that are dependent on I. If UpdateUsers is true,
// and J uses I, then Users is updated to contain J and WriteSet is updated
// to contain any memory locations to which J writes. The function returns
// true if J uses I. By default, alias analysis is used to determine
// whether J reads from memory that overlaps with a location in WriteSet.
// If LoadMoveSet is not null, then it is a previously-computed map
// where the key is the memory-based user instruction and the value is
// the instruction to be compared with I. So, if LoadMoveSet is provided,
// then the alias analysis is not used. This is necessary because this
// function is called during the process of moving instructions during
// vectorization and the results of the alias analysis are not stable during
// that process.
bool BBVectorize::trackUsesOfI(DenseSet<Value *> &Users,
AliasSetTracker &WriteSet, Instruction *I,
Instruction *J, bool UpdateUsers,
DenseSet<ValuePair> *LoadMoveSetPairs) {
bool UsesI = false;
// This instruction may already be marked as a user due, for example, to
// being a member of a selected pair.
if (Users.count(J))
UsesI = true;
if (!UsesI)
for (User::op_iterator JU = J->op_begin(), JE = J->op_end();
JU != JE; ++JU) {
Value *V = *JU;
if (I == V || Users.count(V)) {
UsesI = true;
break;
}
}
if (!UsesI && J->mayReadFromMemory()) {
if (LoadMoveSetPairs) {
UsesI = LoadMoveSetPairs->count(ValuePair(J, I));
} else {
for (AliasSetTracker::iterator W = WriteSet.begin(),
WE = WriteSet.end(); W != WE; ++W) {
if (W->aliasesUnknownInst(J, *AA)) {
UsesI = true;
break;
}
}
}
}
if (UsesI && UpdateUsers) {
if (J->mayWriteToMemory()) WriteSet.add(J);
Users.insert(J);
}
return UsesI;
}
// This function iterates over all instruction pairs in the provided
// basic block and collects all candidate pairs for vectorization.
bool BBVectorize::getCandidatePairs(BasicBlock &BB,
BasicBlock::iterator &Start,
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
DenseSet<ValuePair> &FixedOrderPairs,
DenseMap<ValuePair, int> &CandidatePairCostSavings,
std::vector<Value *> &PairableInsts, bool NonPow2Len) {
size_t TotalPairs = 0;
BasicBlock::iterator E = BB.end();
if (Start == E) return false;
bool ShouldContinue = false, IAfterStart = false;
for (BasicBlock::iterator I = Start++; I != E; ++I) {
if (I == Start) IAfterStart = true;
bool IsSimpleLoadStore;
if (!isInstVectorizable(I, IsSimpleLoadStore)) continue;
// Look for an instruction with which to pair instruction *I...
DenseSet<Value *> Users;
AliasSetTracker WriteSet(*AA);
if (I->mayWriteToMemory()) WriteSet.add(I);
bool JAfterStart = IAfterStart;
BasicBlock::iterator J = std::next(I);
for (unsigned ss = 0; J != E && ss <= Config.SearchLimit; ++J, ++ss) {
if (J == Start) JAfterStart = true;
// Determine if J uses I, if so, exit the loop.
bool UsesI = trackUsesOfI(Users, WriteSet, I, J, !Config.FastDep);
if (Config.FastDep) {
// Note: For this heuristic to be effective, independent operations
// must tend to be intermixed. This is likely to be true from some
// kinds of grouped loop unrolling (but not the generic LLVM pass),
// but otherwise may require some kind of reordering pass.
// When using fast dependency analysis,
// stop searching after first use:
if (UsesI) break;
} else {
if (UsesI) continue;
}
// J does not use I, and comes before the first use of I, so it can be
// merged with I if the instructions are compatible.
int CostSavings, FixedOrder;
if (!areInstsCompatible(I, J, IsSimpleLoadStore, NonPow2Len,
CostSavings, FixedOrder)) continue;
// J is a candidate for merging with I.
if (PairableInsts.empty() ||
PairableInsts[PairableInsts.size()-1] != I) {
PairableInsts.push_back(I);
}
CandidatePairs[I].push_back(J);
++TotalPairs;
if (TTI)
CandidatePairCostSavings.insert(ValuePairWithCost(ValuePair(I, J),
CostSavings));
if (FixedOrder == 1)
FixedOrderPairs.insert(ValuePair(I, J));
else if (FixedOrder == -1)
FixedOrderPairs.insert(ValuePair(J, I));
// The next call to this function must start after the last instruction
// selected during this invocation.
if (JAfterStart) {
Start = std::next(J);
IAfterStart = JAfterStart = false;
}
DEBUG(if (DebugCandidateSelection) dbgs() << "BBV: candidate pair "
<< *I << " <-> " << *J << " (cost savings: " <<
CostSavings << ")\n");
// If we have already found too many pairs, break here and this function
// will be called again starting after the last instruction selected
// during this invocation.
if (PairableInsts.size() >= Config.MaxInsts ||
TotalPairs >= Config.MaxPairs) {
ShouldContinue = true;
break;
}
}
if (ShouldContinue)
break;
}
DEBUG(dbgs() << "BBV: found " << PairableInsts.size()
<< " instructions with candidate pairs\n");
return ShouldContinue;
}
// Finds candidate pairs connected to the pair P = <PI, PJ>. This means that
// it looks for pairs such that both members have an input which is an
// output of PI or PJ.
void BBVectorize::computePairsConnectedTo(
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
DenseSet<ValuePair> &CandidatePairsSet,
std::vector<Value *> &PairableInsts,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
DenseMap<VPPair, unsigned> &PairConnectionTypes,
ValuePair P) {
StoreInst *SI, *SJ;
// For each possible pairing for this variable, look at the uses of
// the first value...
for (Value::user_iterator I = P.first->user_begin(),
E = P.first->user_end();
I != E; ++I) {
User *UI = *I;
if (isa<LoadInst>(UI)) {
// A pair cannot be connected to a load because the load only takes one
// operand (the address) and it is a scalar even after vectorization.
continue;
} else if ((SI = dyn_cast<StoreInst>(UI)) &&
P.first == SI->getPointerOperand()) {
// Similarly, a pair cannot be connected to a store through its
// pointer operand.
continue;
}
// For each use of the first variable, look for uses of the second
// variable...
for (User *UJ : P.second->users()) {
if ((SJ = dyn_cast<StoreInst>(UJ)) &&
P.second == SJ->getPointerOperand())
continue;
// Look for <I, J>:
if (CandidatePairsSet.count(ValuePair(UI, UJ))) {
VPPair VP(P, ValuePair(UI, UJ));
ConnectedPairs[VP.first].push_back(VP.second);
PairConnectionTypes.insert(VPPairWithType(VP, PairConnectionDirect));
}
// Look for <J, I>:
if (CandidatePairsSet.count(ValuePair(UJ, UI))) {
VPPair VP(P, ValuePair(UJ, UI));
ConnectedPairs[VP.first].push_back(VP.second);
PairConnectionTypes.insert(VPPairWithType(VP, PairConnectionSwap));
}
}
if (Config.SplatBreaksChain) continue;
// Look for cases where just the first value in the pair is used by
// both members of another pair (splatting).
for (Value::user_iterator J = P.first->user_begin(); J != E; ++J) {
User *UJ = *J;
if ((SJ = dyn_cast<StoreInst>(UJ)) &&
P.first == SJ->getPointerOperand())
continue;
if (CandidatePairsSet.count(ValuePair(UI, UJ))) {
VPPair VP(P, ValuePair(UI, UJ));
ConnectedPairs[VP.first].push_back(VP.second);
PairConnectionTypes.insert(VPPairWithType(VP, PairConnectionSplat));
}
}
}
if (Config.SplatBreaksChain) return;
// Look for cases where just the second value in the pair is used by
// both members of another pair (splatting).
for (Value::user_iterator I = P.second->user_begin(),
E = P.second->user_end();
I != E; ++I) {
User *UI = *I;
if (isa<LoadInst>(UI))
continue;
else if ((SI = dyn_cast<StoreInst>(UI)) &&
P.second == SI->getPointerOperand())
continue;
for (Value::user_iterator J = P.second->user_begin(); J != E; ++J) {
User *UJ = *J;
if ((SJ = dyn_cast<StoreInst>(UJ)) &&
P.second == SJ->getPointerOperand())
continue;
if (CandidatePairsSet.count(ValuePair(UI, UJ))) {
VPPair VP(P, ValuePair(UI, UJ));
ConnectedPairs[VP.first].push_back(VP.second);
PairConnectionTypes.insert(VPPairWithType(VP, PairConnectionSplat));
}
}
}
}
// This function figures out which pairs are connected. Two pairs are
// connected if some output of the first pair forms an input to both members
// of the second pair.
void BBVectorize::computeConnectedPairs(
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
DenseSet<ValuePair> &CandidatePairsSet,
std::vector<Value *> &PairableInsts,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
DenseMap<VPPair, unsigned> &PairConnectionTypes) {
for (std::vector<Value *>::iterator PI = PairableInsts.begin(),
PE = PairableInsts.end(); PI != PE; ++PI) {
DenseMap<Value *, std::vector<Value *> >::iterator PP =
CandidatePairs.find(*PI);
if (PP == CandidatePairs.end())
continue;
for (std::vector<Value *>::iterator P = PP->second.begin(),
E = PP->second.end(); P != E; ++P)
computePairsConnectedTo(CandidatePairs, CandidatePairsSet,
PairableInsts, ConnectedPairs,
PairConnectionTypes, ValuePair(*PI, *P));
}
DEBUG(size_t TotalPairs = 0;
for (DenseMap<ValuePair, std::vector<ValuePair> >::iterator I =
ConnectedPairs.begin(), IE = ConnectedPairs.end(); I != IE; ++I)
TotalPairs += I->second.size();
dbgs() << "BBV: found " << TotalPairs
<< " pair connections.\n");
}
// This function builds a set of use tuples such that <A, B> is in the set
// if B is in the use dag of A. If B is in the use dag of A, then B
// depends on the output of A.
void BBVectorize::buildDepMap(
BasicBlock &BB,
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
std::vector<Value *> &PairableInsts,
DenseSet<ValuePair> &PairableInstUsers) {
DenseSet<Value *> IsInPair;
for (DenseMap<Value *, std::vector<Value *> >::iterator C =
CandidatePairs.begin(), E = CandidatePairs.end(); C != E; ++C) {
IsInPair.insert(C->first);
IsInPair.insert(C->second.begin(), C->second.end());
}
// Iterate through the basic block, recording all users of each
// pairable instruction.
BasicBlock::iterator E = BB.end(), EL =
BasicBlock::iterator(cast<Instruction>(PairableInsts.back()));
for (BasicBlock::iterator I = BB.getFirstInsertionPt(); I != E; ++I) {
if (IsInPair.find(I) == IsInPair.end()) continue;
DenseSet<Value *> Users;
AliasSetTracker WriteSet(*AA);
if (I->mayWriteToMemory()) WriteSet.add(I);
for (BasicBlock::iterator J = std::next(I); J != E; ++J) {
(void) trackUsesOfI(Users, WriteSet, I, J);
if (J == EL)
break;
}
for (DenseSet<Value *>::iterator U = Users.begin(), E = Users.end();
U != E; ++U) {
if (IsInPair.find(*U) == IsInPair.end()) continue;
PairableInstUsers.insert(ValuePair(I, *U));
}
if (I == EL)
break;
}
}
// Returns true if an input to pair P is an output of pair Q and also an
// input of pair Q is an output of pair P. If this is the case, then these
// two pairs cannot be simultaneously fused.
bool BBVectorize::pairsConflict(ValuePair P, ValuePair Q,
DenseSet<ValuePair> &PairableInstUsers,
DenseMap<ValuePair, std::vector<ValuePair> > *PairableInstUserMap,
DenseSet<VPPair> *PairableInstUserPairSet) {
// Two pairs are in conflict if they are mutual Users of eachother.
bool QUsesP = PairableInstUsers.count(ValuePair(P.first, Q.first)) ||
PairableInstUsers.count(ValuePair(P.first, Q.second)) ||
PairableInstUsers.count(ValuePair(P.second, Q.first)) ||
PairableInstUsers.count(ValuePair(P.second, Q.second));
bool PUsesQ = PairableInstUsers.count(ValuePair(Q.first, P.first)) ||
PairableInstUsers.count(ValuePair(Q.first, P.second)) ||
PairableInstUsers.count(ValuePair(Q.second, P.first)) ||
PairableInstUsers.count(ValuePair(Q.second, P.second));
if (PairableInstUserMap) {
// FIXME: The expensive part of the cycle check is not so much the cycle
// check itself but this edge insertion procedure. This needs some
// profiling and probably a different data structure.
if (PUsesQ) {
if (PairableInstUserPairSet->insert(VPPair(Q, P)).second)
(*PairableInstUserMap)[Q].push_back(P);
}
if (QUsesP) {
if (PairableInstUserPairSet->insert(VPPair(P, Q)).second)
(*PairableInstUserMap)[P].push_back(Q);
}
}
return (QUsesP && PUsesQ);
}
// This function walks the use graph of current pairs to see if, starting
// from P, the walk returns to P.
bool BBVectorize::pairWillFormCycle(ValuePair P,
DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap,
DenseSet<ValuePair> &CurrentPairs) {
DEBUG(if (DebugCycleCheck)
dbgs() << "BBV: starting cycle check for : " << *P.first << " <-> "
<< *P.second << "\n");
// A lookup table of visisted pairs is kept because the PairableInstUserMap
// contains non-direct associations.
DenseSet<ValuePair> Visited;
SmallVector<ValuePair, 32> Q;
// General depth-first post-order traversal:
Q.push_back(P);
do {
ValuePair QTop = Q.pop_back_val();
Visited.insert(QTop);
DEBUG(if (DebugCycleCheck)
dbgs() << "BBV: cycle check visiting: " << *QTop.first << " <-> "
<< *QTop.second << "\n");
DenseMap<ValuePair, std::vector<ValuePair> >::iterator QQ =
PairableInstUserMap.find(QTop);
if (QQ == PairableInstUserMap.end())
continue;
for (std::vector<ValuePair>::iterator C = QQ->second.begin(),
CE = QQ->second.end(); C != CE; ++C) {
if (*C == P) {
DEBUG(dbgs()
<< "BBV: rejected to prevent non-trivial cycle formation: "
<< QTop.first << " <-> " << C->second << "\n");
return true;
}
if (CurrentPairs.count(*C) && !Visited.count(*C))
Q.push_back(*C);
}
} while (!Q.empty());
return false;
}
// This function builds the initial dag of connected pairs with the
// pair J at the root.
void BBVectorize::buildInitialDAGFor(
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
DenseSet<ValuePair> &CandidatePairsSet,
std::vector<Value *> &PairableInsts,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
DenseSet<ValuePair> &PairableInstUsers,
DenseMap<Value *, Value *> &ChosenPairs,
DenseMap<ValuePair, size_t> &DAG, ValuePair J) {
// Each of these pairs is viewed as the root node of a DAG. The DAG
// is then walked (depth-first). As this happens, we keep track of
// the pairs that compose the DAG and the maximum depth of the DAG.
SmallVector<ValuePairWithDepth, 32> Q;
// General depth-first post-order traversal:
Q.push_back(ValuePairWithDepth(J, getDepthFactor(J.first)));
do {
ValuePairWithDepth QTop = Q.back();
// Push each child onto the queue:
bool MoreChildren = false;
size_t MaxChildDepth = QTop.second;
DenseMap<ValuePair, std::vector<ValuePair> >::iterator QQ =
ConnectedPairs.find(QTop.first);
if (QQ != ConnectedPairs.end())
for (std::vector<ValuePair>::iterator k = QQ->second.begin(),
ke = QQ->second.end(); k != ke; ++k) {
// Make sure that this child pair is still a candidate:
if (CandidatePairsSet.count(*k)) {
DenseMap<ValuePair, size_t>::iterator C = DAG.find(*k);
if (C == DAG.end()) {
size_t d = getDepthFactor(k->first);
Q.push_back(ValuePairWithDepth(*k, QTop.second+d));
MoreChildren = true;
} else {
MaxChildDepth = std::max(MaxChildDepth, C->second);
}
}
}
if (!MoreChildren) {
// Record the current pair as part of the DAG:
DAG.insert(ValuePairWithDepth(QTop.first, MaxChildDepth));
Q.pop_back();
}
} while (!Q.empty());
}
// Given some initial dag, prune it by removing conflicting pairs (pairs
// that cannot be simultaneously chosen for vectorization).
void BBVectorize::pruneDAGFor(
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
std::vector<Value *> &PairableInsts,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
DenseSet<ValuePair> &PairableInstUsers,
DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap,
DenseSet<VPPair> &PairableInstUserPairSet,
DenseMap<Value *, Value *> &ChosenPairs,
DenseMap<ValuePair, size_t> &DAG,
DenseSet<ValuePair> &PrunedDAG, ValuePair J,
bool UseCycleCheck) {
SmallVector<ValuePairWithDepth, 32> Q;
// General depth-first post-order traversal:
Q.push_back(ValuePairWithDepth(J, getDepthFactor(J.first)));
do {
ValuePairWithDepth QTop = Q.pop_back_val();
PrunedDAG.insert(QTop.first);
// Visit each child, pruning as necessary...
SmallVector<ValuePairWithDepth, 8> BestChildren;
DenseMap<ValuePair, std::vector<ValuePair> >::iterator QQ =
ConnectedPairs.find(QTop.first);
if (QQ == ConnectedPairs.end())
continue;
for (std::vector<ValuePair>::iterator K = QQ->second.begin(),
KE = QQ->second.end(); K != KE; ++K) {
DenseMap<ValuePair, size_t>::iterator C = DAG.find(*K);
if (C == DAG.end()) continue;
// This child is in the DAG, now we need to make sure it is the
// best of any conflicting children. There could be multiple
// conflicting children, so first, determine if we're keeping
// this child, then delete conflicting children as necessary.
// It is also necessary to guard against pairing-induced
// dependencies. Consider instructions a .. x .. y .. b
// such that (a,b) are to be fused and (x,y) are to be fused
// but a is an input to x and b is an output from y. This
// means that y cannot be moved after b but x must be moved
// after b for (a,b) to be fused. In other words, after
// fusing (a,b) we have y .. a/b .. x where y is an input
// to a/b and x is an output to a/b: x and y can no longer
// be legally fused. To prevent this condition, we must
// make sure that a child pair added to the DAG is not
// both an input and output of an already-selected pair.
// Pairing-induced dependencies can also form from more complicated
// cycles. The pair vs. pair conflicts are easy to check, and so
// that is done explicitly for "fast rejection", and because for
// child vs. child conflicts, we may prefer to keep the current
// pair in preference to the already-selected child.
DenseSet<ValuePair> CurrentPairs;
bool CanAdd = true;
for (SmallVectorImpl<ValuePairWithDepth>::iterator C2
= BestChildren.begin(), E2 = BestChildren.end();
C2 != E2; ++C2) {
if (C2->first.first == C->first.first ||
C2->first.first == C->first.second ||
C2->first.second == C->first.first ||
C2->first.second == C->first.second ||
pairsConflict(C2->first, C->first, PairableInstUsers,
UseCycleCheck ? &PairableInstUserMap : nullptr,
UseCycleCheck ? &PairableInstUserPairSet
: nullptr)) {
if (C2->second >= C->second) {
CanAdd = false;
break;
}
CurrentPairs.insert(C2->first);
}
}
if (!CanAdd) continue;
// Even worse, this child could conflict with another node already
// selected for the DAG. If that is the case, ignore this child.
for (DenseSet<ValuePair>::iterator T = PrunedDAG.begin(),
E2 = PrunedDAG.end(); T != E2; ++T) {
if (T->first == C->first.first ||
T->first == C->first.second ||
T->second == C->first.first ||
T->second == C->first.second ||
pairsConflict(*T, C->first, PairableInstUsers,
UseCycleCheck ? &PairableInstUserMap : nullptr,
UseCycleCheck ? &PairableInstUserPairSet
: nullptr)) {
CanAdd = false;
break;
}
CurrentPairs.insert(*T);
}
if (!CanAdd) continue;
// And check the queue too...
for (SmallVectorImpl<ValuePairWithDepth>::iterator C2 = Q.begin(),
E2 = Q.end(); C2 != E2; ++C2) {
if (C2->first.first == C->first.first ||
C2->first.first == C->first.second ||
C2->first.second == C->first.first ||
C2->first.second == C->first.second ||
pairsConflict(C2->first, C->first, PairableInstUsers,
UseCycleCheck ? &PairableInstUserMap : nullptr,
UseCycleCheck ? &PairableInstUserPairSet
: nullptr)) {
CanAdd = false;
break;
}
CurrentPairs.insert(C2->first);
}
if (!CanAdd) continue;
// Last but not least, check for a conflict with any of the
// already-chosen pairs.
for (DenseMap<Value *, Value *>::iterator C2 =
ChosenPairs.begin(), E2 = ChosenPairs.end();
C2 != E2; ++C2) {
if (pairsConflict(*C2, C->first, PairableInstUsers,
UseCycleCheck ? &PairableInstUserMap : nullptr,
UseCycleCheck ? &PairableInstUserPairSet
: nullptr)) {
CanAdd = false;
break;
}
CurrentPairs.insert(*C2);
}
if (!CanAdd) continue;
// To check for non-trivial cycles formed by the addition of the
// current pair we've formed a list of all relevant pairs, now use a
// graph walk to check for a cycle. We start from the current pair and
// walk the use dag to see if we again reach the current pair. If we
// do, then the current pair is rejected.
// FIXME: It may be more efficient to use a topological-ordering
// algorithm to improve the cycle check. This should be investigated.
if (UseCycleCheck &&
pairWillFormCycle(C->first, PairableInstUserMap, CurrentPairs))
continue;
// This child can be added, but we may have chosen it in preference
// to an already-selected child. Check for this here, and if a
// conflict is found, then remove the previously-selected child
// before adding this one in its place.
for (SmallVectorImpl<ValuePairWithDepth>::iterator C2
= BestChildren.begin(); C2 != BestChildren.end();) {
if (C2->first.first == C->first.first ||
C2->first.first == C->first.second ||
C2->first.second == C->first.first ||
C2->first.second == C->first.second ||
pairsConflict(C2->first, C->first, PairableInstUsers))
C2 = BestChildren.erase(C2);
else
++C2;
}
BestChildren.push_back(ValuePairWithDepth(C->first, C->second));
}
for (SmallVectorImpl<ValuePairWithDepth>::iterator C
= BestChildren.begin(), E2 = BestChildren.end();
C != E2; ++C) {
size_t DepthF = getDepthFactor(C->first.first);
Q.push_back(ValuePairWithDepth(C->first, QTop.second+DepthF));
}
} while (!Q.empty());
}
// This function finds the best dag of mututally-compatible connected
// pairs, given the choice of root pairs as an iterator range.
void BBVectorize::findBestDAGFor(
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
DenseSet<ValuePair> &CandidatePairsSet,
DenseMap<ValuePair, int> &CandidatePairCostSavings,
std::vector<Value *> &PairableInsts,
DenseSet<ValuePair> &FixedOrderPairs,
DenseMap<VPPair, unsigned> &PairConnectionTypes,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps,
DenseSet<ValuePair> &PairableInstUsers,
DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap,
DenseSet<VPPair> &PairableInstUserPairSet,
DenseMap<Value *, Value *> &ChosenPairs,
DenseSet<ValuePair> &BestDAG, size_t &BestMaxDepth,
int &BestEffSize, Value *II, std::vector<Value *>&JJ,
bool UseCycleCheck) {
for (std::vector<Value *>::iterator J = JJ.begin(), JE = JJ.end();
J != JE; ++J) {
ValuePair IJ(II, *J);
if (!CandidatePairsSet.count(IJ))
continue;
// Before going any further, make sure that this pair does not
// conflict with any already-selected pairs (see comment below
// near the DAG pruning for more details).
DenseSet<ValuePair> ChosenPairSet;
bool DoesConflict = false;
for (DenseMap<Value *, Value *>::iterator C = ChosenPairs.begin(),
E = ChosenPairs.end(); C != E; ++C) {
if (pairsConflict(*C, IJ, PairableInstUsers,
UseCycleCheck ? &PairableInstUserMap : nullptr,
UseCycleCheck ? &PairableInstUserPairSet : nullptr)) {
DoesConflict = true;
break;
}
ChosenPairSet.insert(*C);
}
if (DoesConflict) continue;
if (UseCycleCheck &&
pairWillFormCycle(IJ, PairableInstUserMap, ChosenPairSet))
continue;
DenseMap<ValuePair, size_t> DAG;
buildInitialDAGFor(CandidatePairs, CandidatePairsSet,
PairableInsts, ConnectedPairs,
PairableInstUsers, ChosenPairs, DAG, IJ);
// Because we'll keep the child with the largest depth, the largest
// depth is still the same in the unpruned DAG.
size_t MaxDepth = DAG.lookup(IJ);
DEBUG(if (DebugPairSelection) dbgs() << "BBV: found DAG for pair {"
<< *IJ.first << " <-> " << *IJ.second << "} of depth " <<
MaxDepth << " and size " << DAG.size() << "\n");
// At this point the DAG has been constructed, but, may contain
// contradictory children (meaning that different children of
// some dag node may be attempting to fuse the same instruction).
// So now we walk the dag again, in the case of a conflict,
// keep only the child with the largest depth. To break a tie,
// favor the first child.
DenseSet<ValuePair> PrunedDAG;
pruneDAGFor(CandidatePairs, PairableInsts, ConnectedPairs,
PairableInstUsers, PairableInstUserMap,
PairableInstUserPairSet,
ChosenPairs, DAG, PrunedDAG, IJ, UseCycleCheck);
int EffSize = 0;
if (TTI) {
DenseSet<Value *> PrunedDAGInstrs;
for (DenseSet<ValuePair>::iterator S = PrunedDAG.begin(),
E = PrunedDAG.end(); S != E; ++S) {
PrunedDAGInstrs.insert(S->first);
PrunedDAGInstrs.insert(S->second);
}
// The set of pairs that have already contributed to the total cost.
DenseSet<ValuePair> IncomingPairs;
// If the cost model were perfect, this might not be necessary; but we
// need to make sure that we don't get stuck vectorizing our own
// shuffle chains.
bool HasNontrivialInsts = false;
// The node weights represent the cost savings associated with
// fusing the pair of instructions.
for (DenseSet<ValuePair>::iterator S = PrunedDAG.begin(),
E = PrunedDAG.end(); S != E; ++S) {
if (!isa<ShuffleVectorInst>(S->first) &&
!isa<InsertElementInst>(S->first) &&
!isa<ExtractElementInst>(S->first))
HasNontrivialInsts = true;
bool FlipOrder = false;
if (getDepthFactor(S->first)) {
int ESContrib = CandidatePairCostSavings.find(*S)->second;
DEBUG(if (DebugPairSelection) dbgs() << "\tweight {"
<< *S->first << " <-> " << *S->second << "} = " <<
ESContrib << "\n");
EffSize += ESContrib;
}
// The edge weights contribute in a negative sense: they represent
// the cost of shuffles.
DenseMap<ValuePair, std::vector<ValuePair> >::iterator SS =
ConnectedPairDeps.find(*S);
if (SS != ConnectedPairDeps.end()) {
unsigned NumDepsDirect = 0, NumDepsSwap = 0;
for (std::vector<ValuePair>::iterator T = SS->second.begin(),
TE = SS->second.end(); T != TE; ++T) {
VPPair Q(*S, *T);
if (!PrunedDAG.count(Q.second))
continue;
DenseMap<VPPair, unsigned>::iterator R =
PairConnectionTypes.find(VPPair(Q.second, Q.first));
assert(R != PairConnectionTypes.end() &&
"Cannot find pair connection type");
if (R->second == PairConnectionDirect)
++NumDepsDirect;
else if (R->second == PairConnectionSwap)
++NumDepsSwap;
}
// If there are more swaps than direct connections, then
// the pair order will be flipped during fusion. So the real
// number of swaps is the minimum number.
FlipOrder = !FixedOrderPairs.count(*S) &&
((NumDepsSwap > NumDepsDirect) ||
FixedOrderPairs.count(ValuePair(S->second, S->first)));
for (std::vector<ValuePair>::iterator T = SS->second.begin(),
TE = SS->second.end(); T != TE; ++T) {
VPPair Q(*S, *T);
if (!PrunedDAG.count(Q.second))
continue;
DenseMap<VPPair, unsigned>::iterator R =
PairConnectionTypes.find(VPPair(Q.second, Q.first));
assert(R != PairConnectionTypes.end() &&
"Cannot find pair connection type");
Type *Ty1 = Q.second.first->getType(),
*Ty2 = Q.second.second->getType();
Type *VTy = getVecTypeForPair(Ty1, Ty2);
if ((R->second == PairConnectionDirect && FlipOrder) ||
(R->second == PairConnectionSwap && !FlipOrder) ||
R->second == PairConnectionSplat) {
int ESContrib = (int) getInstrCost(Instruction::ShuffleVector,
VTy, VTy);
if (VTy->getVectorNumElements() == 2) {
if (R->second == PairConnectionSplat)
ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost(
TargetTransformInfo::SK_Broadcast, VTy));
else
ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost(
TargetTransformInfo::SK_Reverse, VTy));
}
DEBUG(if (DebugPairSelection) dbgs() << "\tcost {" <<
*Q.second.first << " <-> " << *Q.second.second <<
"} -> {" <<
*S->first << " <-> " << *S->second << "} = " <<
ESContrib << "\n");
EffSize -= ESContrib;
}
}
}
// Compute the cost of outgoing edges. We assume that edges outgoing
// to shuffles, inserts or extracts can be merged, and so contribute
// no additional cost.
if (!S->first->getType()->isVoidTy()) {
Type *Ty1 = S->first->getType(),
*Ty2 = S->second->getType();
Type *VTy = getVecTypeForPair(Ty1, Ty2);
bool NeedsExtraction = false;
for (User *U : S->first->users()) {
if (ShuffleVectorInst *SI = dyn_cast<ShuffleVectorInst>(U)) {
// Shuffle can be folded if it has no other input
if (isa<UndefValue>(SI->getOperand(1)))
continue;
}
if (isa<ExtractElementInst>(U))
continue;
if (PrunedDAGInstrs.count(U))
continue;
NeedsExtraction = true;
break;
}
if (NeedsExtraction) {
int ESContrib;
if (Ty1->isVectorTy()) {
ESContrib = (int) getInstrCost(Instruction::ShuffleVector,
Ty1, VTy);
ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost(
TargetTransformInfo::SK_ExtractSubvector, VTy, 0, Ty1));
} else
ESContrib = (int) TTI->getVectorInstrCost(
Instruction::ExtractElement, VTy, 0);
DEBUG(if (DebugPairSelection) dbgs() << "\tcost {" <<
*S->first << "} = " << ESContrib << "\n");
EffSize -= ESContrib;
}
NeedsExtraction = false;
for (User *U : S->second->users()) {
if (ShuffleVectorInst *SI = dyn_cast<ShuffleVectorInst>(U)) {
// Shuffle can be folded if it has no other input
if (isa<UndefValue>(SI->getOperand(1)))
continue;
}
if (isa<ExtractElementInst>(U))
continue;
if (PrunedDAGInstrs.count(U))
continue;
NeedsExtraction = true;
break;
}
if (NeedsExtraction) {
int ESContrib;
if (Ty2->isVectorTy()) {
ESContrib = (int) getInstrCost(Instruction::ShuffleVector,
Ty2, VTy);
ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost(
TargetTransformInfo::SK_ExtractSubvector, VTy,
Ty1->isVectorTy() ? Ty1->getVectorNumElements() : 1, Ty2));
} else
ESContrib = (int) TTI->getVectorInstrCost(
Instruction::ExtractElement, VTy, 1);
DEBUG(if (DebugPairSelection) dbgs() << "\tcost {" <<
*S->second << "} = " << ESContrib << "\n");
EffSize -= ESContrib;
}
}
// Compute the cost of incoming edges.
if (!isa<LoadInst>(S->first) && !isa<StoreInst>(S->first)) {
Instruction *S1 = cast<Instruction>(S->first),
*S2 = cast<Instruction>(S->second);
for (unsigned o = 0; o < S1->getNumOperands(); ++o) {
Value *O1 = S1->getOperand(o), *O2 = S2->getOperand(o);
// Combining constants into vector constants (or small vector
// constants into larger ones are assumed free).
if (isa<Constant>(O1) && isa<Constant>(O2))
continue;
if (FlipOrder)
std::swap(O1, O2);
ValuePair VP = ValuePair(O1, O2);
ValuePair VPR = ValuePair(O2, O1);
// Internal edges are not handled here.
if (PrunedDAG.count(VP) || PrunedDAG.count(VPR))
continue;
Type *Ty1 = O1->getType(),
*Ty2 = O2->getType();
Type *VTy = getVecTypeForPair(Ty1, Ty2);
// Combining vector operations of the same type is also assumed
// folded with other operations.
if (Ty1 == Ty2) {
// If both are insert elements, then both can be widened.
InsertElementInst *IEO1 = dyn_cast<InsertElementInst>(O1),
*IEO2 = dyn_cast<InsertElementInst>(O2);
if (IEO1 && IEO2 && isPureIEChain(IEO1) && isPureIEChain(IEO2))
continue;
// If both are extract elements, and both have the same input
// type, then they can be replaced with a shuffle
ExtractElementInst *EIO1 = dyn_cast<ExtractElementInst>(O1),
*EIO2 = dyn_cast<ExtractElementInst>(O2);
if (EIO1 && EIO2 &&
EIO1->getOperand(0)->getType() ==
EIO2->getOperand(0)->getType())
continue;
// If both are a shuffle with equal operand types and only two
// unqiue operands, then they can be replaced with a single
// shuffle
ShuffleVectorInst *SIO1 = dyn_cast<ShuffleVectorInst>(O1),
*SIO2 = dyn_cast<ShuffleVectorInst>(O2);
if (SIO1 && SIO2 &&
SIO1->getOperand(0)->getType() ==
SIO2->getOperand(0)->getType()) {
SmallSet<Value *, 4> SIOps;
SIOps.insert(SIO1->getOperand(0));
SIOps.insert(SIO1->getOperand(1));
SIOps.insert(SIO2->getOperand(0));
SIOps.insert(SIO2->getOperand(1));
if (SIOps.size() <= 2)
continue;
}
}
int ESContrib;
// This pair has already been formed.
if (IncomingPairs.count(VP)) {
continue;
} else if (IncomingPairs.count(VPR)) {
ESContrib = (int) getInstrCost(Instruction::ShuffleVector,
VTy, VTy);
if (VTy->getVectorNumElements() == 2)
ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost(
TargetTransformInfo::SK_Reverse, VTy));
} else if (!Ty1->isVectorTy() && !Ty2->isVectorTy()) {
ESContrib = (int) TTI->getVectorInstrCost(
Instruction::InsertElement, VTy, 0);
ESContrib += (int) TTI->getVectorInstrCost(
Instruction::InsertElement, VTy, 1);
} else if (!Ty1->isVectorTy()) {
// O1 needs to be inserted into a vector of size O2, and then
// both need to be shuffled together.
ESContrib = (int) TTI->getVectorInstrCost(
Instruction::InsertElement, Ty2, 0);
ESContrib += (int) getInstrCost(Instruction::ShuffleVector,
VTy, Ty2);
} else if (!Ty2->isVectorTy()) {
// O2 needs to be inserted into a vector of size O1, and then
// both need to be shuffled together.
ESContrib = (int) TTI->getVectorInstrCost(
Instruction::InsertElement, Ty1, 0);
ESContrib += (int) getInstrCost(Instruction::ShuffleVector,
VTy, Ty1);
} else {
Type *TyBig = Ty1, *TySmall = Ty2;
if (Ty2->getVectorNumElements() > Ty1->getVectorNumElements())
std::swap(TyBig, TySmall);
ESContrib = (int) getInstrCost(Instruction::ShuffleVector,
VTy, TyBig);
if (TyBig != TySmall)
ESContrib += (int) getInstrCost(Instruction::ShuffleVector,
TyBig, TySmall);
}
DEBUG(if (DebugPairSelection) dbgs() << "\tcost {"
<< *O1 << " <-> " << *O2 << "} = " <<
ESContrib << "\n");
EffSize -= ESContrib;
IncomingPairs.insert(VP);
}
}
}
if (!HasNontrivialInsts) {
DEBUG(if (DebugPairSelection) dbgs() <<
"\tNo non-trivial instructions in DAG;"
" override to zero effective size\n");
EffSize = 0;
}
} else {
for (DenseSet<ValuePair>::iterator S = PrunedDAG.begin(),
E = PrunedDAG.end(); S != E; ++S)
EffSize += (int) getDepthFactor(S->first);
}
DEBUG(if (DebugPairSelection)
dbgs() << "BBV: found pruned DAG for pair {"
<< *IJ.first << " <-> " << *IJ.second << "} of depth " <<
MaxDepth << " and size " << PrunedDAG.size() <<
" (effective size: " << EffSize << ")\n");
if (((TTI && !UseChainDepthWithTI) ||
MaxDepth >= Config.ReqChainDepth) &&
EffSize > 0 && EffSize > BestEffSize) {
BestMaxDepth = MaxDepth;
BestEffSize = EffSize;
BestDAG = PrunedDAG;
}
}
}
// Given the list of candidate pairs, this function selects those
// that will be fused into vector instructions.
void BBVectorize::choosePairs(
DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
DenseSet<ValuePair> &CandidatePairsSet,
DenseMap<ValuePair, int> &CandidatePairCostSavings,
std::vector<Value *> &PairableInsts,
DenseSet<ValuePair> &FixedOrderPairs,
DenseMap<VPPair, unsigned> &PairConnectionTypes,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps,
DenseSet<ValuePair> &PairableInstUsers,
DenseMap<Value *, Value *>& ChosenPairs) {
bool UseCycleCheck =
CandidatePairsSet.size() <= Config.MaxCandPairsForCycleCheck;
DenseMap<Value *, std::vector<Value *> > CandidatePairs2;
for (DenseSet<ValuePair>::iterator I = CandidatePairsSet.begin(),
E = CandidatePairsSet.end(); I != E; ++I) {
std::vector<Value *> &JJ = CandidatePairs2[I->second];
if (JJ.empty()) JJ.reserve(32);
JJ.push_back(I->first);
}
DenseMap<ValuePair, std::vector<ValuePair> > PairableInstUserMap;
DenseSet<VPPair> PairableInstUserPairSet;
for (std::vector<Value *>::iterator I = PairableInsts.begin(),
E = PairableInsts.end(); I != E; ++I) {
// The number of possible pairings for this variable:
size_t NumChoices = CandidatePairs.lookup(*I).size();
if (!NumChoices) continue;
std::vector<Value *> &JJ = CandidatePairs[*I];
// The best pair to choose and its dag:
size_t BestMaxDepth = 0;
int BestEffSize = 0;
DenseSet<ValuePair> BestDAG;
findBestDAGFor(CandidatePairs, CandidatePairsSet,
CandidatePairCostSavings,
PairableInsts, FixedOrderPairs, PairConnectionTypes,
ConnectedPairs, ConnectedPairDeps,
PairableInstUsers, PairableInstUserMap,
PairableInstUserPairSet, ChosenPairs,
BestDAG, BestMaxDepth, BestEffSize, *I, JJ,
UseCycleCheck);
if (BestDAG.empty())
continue;
// A dag has been chosen (or not) at this point. If no dag was
// chosen, then this instruction, I, cannot be paired (and is no longer
// considered).
DEBUG(dbgs() << "BBV: selected pairs in the best DAG for: "
<< *cast<Instruction>(*I) << "\n");
for (DenseSet<ValuePair>::iterator S = BestDAG.begin(),
SE2 = BestDAG.end(); S != SE2; ++S) {
// Insert the members of this dag into the list of chosen pairs.
ChosenPairs.insert(ValuePair(S->first, S->second));
DEBUG(dbgs() << "BBV: selected pair: " << *S->first << " <-> " <<
*S->second << "\n");
// Remove all candidate pairs that have values in the chosen dag.
std::vector<Value *> &KK = CandidatePairs[S->first];
for (std::vector<Value *>::iterator K = KK.begin(), KE = KK.end();
K != KE; ++K) {
if (*K == S->second)
continue;
CandidatePairsSet.erase(ValuePair(S->first, *K));
}
std::vector<Value *> &LL = CandidatePairs2[S->second];
for (std::vector<Value *>::iterator L = LL.begin(), LE = LL.end();
L != LE; ++L) {
if (*L == S->first)
continue;
CandidatePairsSet.erase(ValuePair(*L, S->second));
}
std::vector<Value *> &MM = CandidatePairs[S->second];
for (std::vector<Value *>::iterator M = MM.begin(), ME = MM.end();
M != ME; ++M) {
assert(*M != S->first && "Flipped pair in candidate list?");
CandidatePairsSet.erase(ValuePair(S->second, *M));
}
std::vector<Value *> &NN = CandidatePairs2[S->first];
for (std::vector<Value *>::iterator N = NN.begin(), NE = NN.end();
N != NE; ++N) {
assert(*N != S->second && "Flipped pair in candidate list?");
CandidatePairsSet.erase(ValuePair(*N, S->first));
}
}
}
DEBUG(dbgs() << "BBV: selected " << ChosenPairs.size() << " pairs.\n");
}
std::string getReplacementName(Instruction *I, bool IsInput, unsigned o,
unsigned n = 0) {
if (!I->hasName())
return "";
return (I->getName() + (IsInput ? ".v.i" : ".v.r") + utostr(o) +
(n > 0 ? "." + utostr(n) : "")).str();
}
// Returns the value that is to be used as the pointer input to the vector
// instruction that fuses I with J.
Value *BBVectorize::getReplacementPointerInput(LLVMContext& Context,
Instruction *I, Instruction *J, unsigned o) {
Value *IPtr, *JPtr;
unsigned IAlignment, JAlignment, IAddressSpace, JAddressSpace;
int64_t OffsetInElmts;
// Note: the analysis might fail here, that is why the pair order has
// been precomputed (OffsetInElmts must be unused here).
(void) getPairPtrInfo(I, J, IPtr, JPtr, IAlignment, JAlignment,
IAddressSpace, JAddressSpace,
OffsetInElmts, false);
// The pointer value is taken to be the one with the lowest offset.
Value *VPtr = IPtr;
Type *ArgTypeI = IPtr->getType()->getPointerElementType();
Type *ArgTypeJ = JPtr->getType()->getPointerElementType();
Type *VArgType = getVecTypeForPair(ArgTypeI, ArgTypeJ);
Type *VArgPtrType
= PointerType::get(VArgType,
IPtr->getType()->getPointerAddressSpace());
return new BitCastInst(VPtr, VArgPtrType, getReplacementName(I, true, o),
/* insert before */ I);
}
void BBVectorize::fillNewShuffleMask(LLVMContext& Context, Instruction *J,
unsigned MaskOffset, unsigned NumInElem,
unsigned NumInElem1, unsigned IdxOffset,
std::vector<Constant*> &Mask) {
unsigned NumElem1 = J->getType()->getVectorNumElements();
for (unsigned v = 0; v < NumElem1; ++v) {
int m = cast<ShuffleVectorInst>(J)->getMaskValue(v);
if (m < 0) {
Mask[v+MaskOffset] = UndefValue::get(Type::getInt32Ty(Context));
} else {
unsigned mm = m + (int) IdxOffset;
if (m >= (int) NumInElem1)
mm += (int) NumInElem;
Mask[v+MaskOffset] =
ConstantInt::get(Type::getInt32Ty(Context), mm);
}
}
}
// Returns the value that is to be used as the vector-shuffle mask to the
// vector instruction that fuses I with J.
Value *BBVectorize::getReplacementShuffleMask(LLVMContext& Context,
Instruction *I, Instruction *J) {
// This is the shuffle mask. We need to append the second
// mask to the first, and the numbers need to be adjusted.
Type *ArgTypeI = I->getType();
Type *ArgTypeJ = J->getType();
Type *VArgType = getVecTypeForPair(ArgTypeI, ArgTypeJ);
unsigned NumElemI = ArgTypeI->getVectorNumElements();
// Get the total number of elements in the fused vector type.
// By definition, this must equal the number of elements in
// the final mask.
unsigned NumElem = VArgType->getVectorNumElements();
std::vector<Constant*> Mask(NumElem);
Type *OpTypeI = I->getOperand(0)->getType();
unsigned NumInElemI = OpTypeI->getVectorNumElements();
Type *OpTypeJ = J->getOperand(0)->getType();
unsigned NumInElemJ = OpTypeJ->getVectorNumElements();
// The fused vector will be:
// -----------------------------------------------------
// | NumInElemI | NumInElemJ | NumInElemI | NumInElemJ |
// -----------------------------------------------------
// from which we'll extract NumElem total elements (where the first NumElemI
// of them come from the mask in I and the remainder come from the mask
// in J.
// For the mask from the first pair...
fillNewShuffleMask(Context, I, 0, NumInElemJ, NumInElemI,
0, Mask);
// For the mask from the second pair...
fillNewShuffleMask(Context, J, NumElemI, NumInElemI, NumInElemJ,
NumInElemI, Mask);
return ConstantVector::get(Mask);
}
bool BBVectorize::expandIEChain(LLVMContext& Context, Instruction *I,
Instruction *J, unsigned o, Value *&LOp,
unsigned numElemL,
Type *ArgTypeL, Type *ArgTypeH,
bool IBeforeJ, unsigned IdxOff) {
bool ExpandedIEChain = false;
if (InsertElementInst *LIE = dyn_cast<InsertElementInst>(LOp)) {
// If we have a pure insertelement chain, then this can be rewritten
// into a chain that directly builds the larger type.
if (isPureIEChain(LIE)) {
SmallVector<Value *, 8> VectElemts(numElemL,
UndefValue::get(ArgTypeL->getScalarType()));
InsertElementInst *LIENext = LIE;
do {
unsigned Idx =
cast<ConstantInt>(LIENext->getOperand(2))->getSExtValue();
VectElemts[Idx] = LIENext->getOperand(1);
} while ((LIENext =
dyn_cast<InsertElementInst>(LIENext->getOperand(0))));
LIENext = nullptr;
Value *LIEPrev = UndefValue::get(ArgTypeH);
for (unsigned i = 0; i < numElemL; ++i) {
if (isa<UndefValue>(VectElemts[i])) continue;
LIENext = InsertElementInst::Create(LIEPrev, VectElemts[i],
ConstantInt::get(Type::getInt32Ty(Context),
i + IdxOff),
getReplacementName(IBeforeJ ? I : J,
true, o, i+1));
LIENext->insertBefore(IBeforeJ ? J : I);
LIEPrev = LIENext;
}
LOp = LIENext ? (Value*) LIENext : UndefValue::get(ArgTypeH);
ExpandedIEChain = true;
}
}
return ExpandedIEChain;
}
static unsigned getNumScalarElements(Type *Ty) {
if (VectorType *VecTy = dyn_cast<VectorType>(Ty))
return VecTy->getNumElements();
return 1;
}
// Returns the value to be used as the specified operand of the vector
// instruction that fuses I with J.
Value *BBVectorize::getReplacementInput(LLVMContext& Context, Instruction *I,
Instruction *J, unsigned o, bool IBeforeJ) {
Value *CV0 = ConstantInt::get(Type::getInt32Ty(Context), 0);
Value *CV1 = ConstantInt::get(Type::getInt32Ty(Context), 1);
// Compute the fused vector type for this operand
Type *ArgTypeI = I->getOperand(o)->getType();
Type *ArgTypeJ = J->getOperand(o)->getType();
VectorType *VArgType = getVecTypeForPair(ArgTypeI, ArgTypeJ);
Instruction *L = I, *H = J;
Type *ArgTypeL = ArgTypeI, *ArgTypeH = ArgTypeJ;
unsigned numElemL = getNumScalarElements(ArgTypeL);
unsigned numElemH = getNumScalarElements(ArgTypeH);
Value *LOp = L->getOperand(o);
Value *HOp = H->getOperand(o);
unsigned numElem = VArgType->getNumElements();
// First, we check if we can reuse the "original" vector outputs (if these
// exist). We might need a shuffle.
ExtractElementInst *LEE = dyn_cast<ExtractElementInst>(LOp);
ExtractElementInst *HEE = dyn_cast<ExtractElementInst>(HOp);
ShuffleVectorInst *LSV = dyn_cast<ShuffleVectorInst>(LOp);
ShuffleVectorInst *HSV = dyn_cast<ShuffleVectorInst>(HOp);
// FIXME: If we're fusing shuffle instructions, then we can't apply this
// optimization. The input vectors to the shuffle might be a different
// length from the shuffle outputs. Unfortunately, the replacement
// shuffle mask has already been formed, and the mask entries are sensitive
// to the sizes of the inputs.
bool IsSizeChangeShuffle =
isa<ShuffleVectorInst>(L) &&
(LOp->getType() != L->getType() || HOp->getType() != H->getType());
if ((LEE || LSV) && (HEE || HSV) && !IsSizeChangeShuffle) {
// We can have at most two unique vector inputs.
bool CanUseInputs = true;
Value *I1, *I2 = nullptr;
if (LEE) {
I1 = LEE->getOperand(0);
} else {
I1 = LSV->getOperand(0);
I2 = LSV->getOperand(1);
if (I2 == I1 || isa<UndefValue>(I2))
I2 = nullptr;
}
if (HEE) {
Value *I3 = HEE->getOperand(0);
if (!I2 && I3 != I1)
I2 = I3;
else if (I3 != I1 && I3 != I2)
CanUseInputs = false;
} else {
Value *I3 = HSV->getOperand(0);
if (!I2 && I3 != I1)
I2 = I3;
else if (I3 != I1 && I3 != I2)
CanUseInputs = false;
if (CanUseInputs) {
Value *I4 = HSV->getOperand(1);
if (!isa<UndefValue>(I4)) {
if (!I2 && I4 != I1)
I2 = I4;
else if (I4 != I1 && I4 != I2)
CanUseInputs = false;
}
}
}
if (CanUseInputs) {
unsigned LOpElem =
cast<Instruction>(LOp)->getOperand(0)->getType()
->getVectorNumElements();
unsigned HOpElem =
cast<Instruction>(HOp)->getOperand(0)->getType()
->getVectorNumElements();
// We have one or two input vectors. We need to map each index of the
// operands to the index of the original vector.
SmallVector<std::pair<int, int>, 8> II(numElem);
for (unsigned i = 0; i < numElemL; ++i) {
int Idx, INum;
if (LEE) {
Idx =
cast<ConstantInt>(LEE->getOperand(1))->getSExtValue();
INum = LEE->getOperand(0) == I1 ? 0 : 1;
} else {
Idx = LSV->getMaskValue(i);
if (Idx < (int) LOpElem) {
INum = LSV->getOperand(0) == I1 ? 0 : 1;
} else {
Idx -= LOpElem;
INum = LSV->getOperand(1) == I1 ? 0 : 1;
}
}
II[i] = std::pair<int, int>(Idx, INum);
}
for (unsigned i = 0; i < numElemH; ++i) {
int Idx, INum;
if (HEE) {
Idx =
cast<ConstantInt>(HEE->getOperand(1))->getSExtValue();
INum = HEE->getOperand(0) == I1 ? 0 : 1;
} else {
Idx = HSV->getMaskValue(i);
if (Idx < (int) HOpElem) {
INum = HSV->getOperand(0) == I1 ? 0 : 1;
} else {
Idx -= HOpElem;
INum = HSV->getOperand(1) == I1 ? 0 : 1;
}
}
II[i + numElemL] = std::pair<int, int>(Idx, INum);
}
// We now have an array which tells us from which index of which
// input vector each element of the operand comes.
VectorType *I1T = cast<VectorType>(I1->getType());
unsigned I1Elem = I1T->getNumElements();
if (!I2) {
// In this case there is only one underlying vector input. Check for
// the trivial case where we can use the input directly.
if (I1Elem == numElem) {
bool ElemInOrder = true;
for (unsigned i = 0; i < numElem; ++i) {
if (II[i].first != (int) i && II[i].first != -1) {
ElemInOrder = false;
break;
}
}
if (ElemInOrder)
return I1;
}
// A shuffle is needed.
std::vector<Constant *> Mask(numElem);
for (unsigned i = 0; i < numElem; ++i) {
int Idx = II[i].first;
if (Idx == -1)
Mask[i] = UndefValue::get(Type::getInt32Ty(Context));
else
Mask[i] = ConstantInt::get(Type::getInt32Ty(Context), Idx);
}
Instruction *S =
new ShuffleVectorInst(I1, UndefValue::get(I1T),
ConstantVector::get(Mask),
getReplacementName(IBeforeJ ? I : J,
true, o));
S->insertBefore(IBeforeJ ? J : I);
return S;
}
VectorType *I2T = cast<VectorType>(I2->getType());
unsigned I2Elem = I2T->getNumElements();
// This input comes from two distinct vectors. The first step is to
// make sure that both vectors are the same length. If not, the
// smaller one will need to grow before they can be shuffled together.
if (I1Elem < I2Elem) {
std::vector<Constant *> Mask(I2Elem);
unsigned v = 0;
for (; v < I1Elem; ++v)
Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), v);
for (; v < I2Elem; ++v)
Mask[v] = UndefValue::get(Type::getInt32Ty(Context));
Instruction *NewI1 =
new ShuffleVectorInst(I1, UndefValue::get(I1T),
ConstantVector::get(Mask),
getReplacementName(IBeforeJ ? I : J,
true, o, 1));
NewI1->insertBefore(IBeforeJ ? J : I);
I1 = NewI1;
I1Elem = I2Elem;
} else if (I1Elem > I2Elem) {
std::vector<Constant *> Mask(I1Elem);
unsigned v = 0;
for (; v < I2Elem; ++v)
Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), v);
for (; v < I1Elem; ++v)
Mask[v] = UndefValue::get(Type::getInt32Ty(Context));
Instruction *NewI2 =
new ShuffleVectorInst(I2, UndefValue::get(I2T),
ConstantVector::get(Mask),
getReplacementName(IBeforeJ ? I : J,
true, o, 1));
NewI2->insertBefore(IBeforeJ ? J : I);
I2 = NewI2;
}
// Now that both I1 and I2 are the same length we can shuffle them
// together (and use the result).
std::vector<Constant *> Mask(numElem);
for (unsigned v = 0; v < numElem; ++v) {
if (II[v].first == -1) {
Mask[v] = UndefValue::get(Type::getInt32Ty(Context));
} else {
int Idx = II[v].first + II[v].second * I1Elem;
Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), Idx);
}
}
Instruction *NewOp =
new ShuffleVectorInst(I1, I2, ConstantVector::get(Mask),
getReplacementName(IBeforeJ ? I : J, true, o));
NewOp->insertBefore(IBeforeJ ? J : I);
return NewOp;
}
}
Type *ArgType = ArgTypeL;
if (numElemL < numElemH) {
if (numElemL == 1 && expandIEChain(Context, I, J, o, HOp, numElemH,
ArgTypeL, VArgType, IBeforeJ, 1)) {
// This is another short-circuit case: we're combining a scalar into
// a vector that is formed by an IE chain. We've just expanded the IE
// chain, now insert the scalar and we're done.
Instruction *S = InsertElementInst::Create(HOp, LOp, CV0,
getReplacementName(IBeforeJ ? I : J, true, o));
S->insertBefore(IBeforeJ ? J : I);
return S;
} else if (!expandIEChain(Context, I, J, o, LOp, numElemL, ArgTypeL,
ArgTypeH, IBeforeJ)) {
// The two vector inputs to the shuffle must be the same length,
// so extend the smaller vector to be the same length as the larger one.
Instruction *NLOp;
if (numElemL > 1) {
std::vector<Constant *> Mask(numElemH);
unsigned v = 0;
for (; v < numElemL; ++v)
Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), v);
for (; v < numElemH; ++v)
Mask[v] = UndefValue::get(Type::getInt32Ty(Context));
NLOp = new ShuffleVectorInst(LOp, UndefValue::get(ArgTypeL),
ConstantVector::get(Mask),
getReplacementName(IBeforeJ ? I : J,
true, o, 1));
} else {
NLOp = InsertElementInst::Create(UndefValue::get(ArgTypeH), LOp, CV0,
getReplacementName(IBeforeJ ? I : J,
true, o, 1));
}
NLOp->insertBefore(IBeforeJ ? J : I);
LOp = NLOp;
}
ArgType = ArgTypeH;
} else if (numElemL > numElemH) {
if (numElemH == 1 && expandIEChain(Context, I, J, o, LOp, numElemL,
ArgTypeH, VArgType, IBeforeJ)) {
Instruction *S =
InsertElementInst::Create(LOp, HOp,
ConstantInt::get(Type::getInt32Ty(Context),
numElemL),
getReplacementName(IBeforeJ ? I : J,
true, o));
S->insertBefore(IBeforeJ ? J : I);
return S;
} else if (!expandIEChain(Context, I, J, o, HOp, numElemH, ArgTypeH,
ArgTypeL, IBeforeJ)) {
Instruction *NHOp;
if (numElemH > 1) {
std::vector<Constant *> Mask(numElemL);
unsigned v = 0;
for (; v < numElemH; ++v)
Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), v);
for (; v < numElemL; ++v)
Mask[v] = UndefValue::get(Type::getInt32Ty(Context));
NHOp = new ShuffleVectorInst(HOp, UndefValue::get(ArgTypeH),
ConstantVector::get(Mask),
getReplacementName(IBeforeJ ? I : J,
true, o, 1));
} else {
NHOp = InsertElementInst::Create(UndefValue::get(ArgTypeL), HOp, CV0,
getReplacementName(IBeforeJ ? I : J,
true, o, 1));
}
NHOp->insertBefore(IBeforeJ ? J : I);
HOp = NHOp;
}
}
if (ArgType->isVectorTy()) {
unsigned numElem = VArgType->getVectorNumElements();
std::vector<Constant*> Mask(numElem);
for (unsigned v = 0; v < numElem; ++v) {
unsigned Idx = v;
// If the low vector was expanded, we need to skip the extra
// undefined entries.
if (v >= numElemL && numElemH > numElemL)
Idx += (numElemH - numElemL);
Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), Idx);
}
Instruction *BV = new ShuffleVectorInst(LOp, HOp,
ConstantVector::get(Mask),
getReplacementName(IBeforeJ ? I : J, true, o));
BV->insertBefore(IBeforeJ ? J : I);
return BV;
}
Instruction *BV1 = InsertElementInst::Create(
UndefValue::get(VArgType), LOp, CV0,
getReplacementName(IBeforeJ ? I : J,
true, o, 1));
BV1->insertBefore(IBeforeJ ? J : I);
Instruction *BV2 = InsertElementInst::Create(BV1, HOp, CV1,
getReplacementName(IBeforeJ ? I : J,
true, o, 2));
BV2->insertBefore(IBeforeJ ? J : I);
return BV2;
}
// This function creates an array of values that will be used as the inputs
// to the vector instruction that fuses I with J.
void BBVectorize::getReplacementInputsForPair(LLVMContext& Context,
Instruction *I, Instruction *J,
SmallVectorImpl<Value *> &ReplacedOperands,
bool IBeforeJ) {
unsigned NumOperands = I->getNumOperands();
for (unsigned p = 0, o = NumOperands-1; p < NumOperands; ++p, --o) {
// Iterate backward so that we look at the store pointer
// first and know whether or not we need to flip the inputs.
if (isa<LoadInst>(I) || (o == 1 && isa<StoreInst>(I))) {
// This is the pointer for a load/store instruction.
ReplacedOperands[o] = getReplacementPointerInput(Context, I, J, o);
continue;
} else if (isa<CallInst>(I)) {
Function *F = cast<CallInst>(I)->getCalledFunction();
Intrinsic::ID IID = F->getIntrinsicID();
if (o == NumOperands-1) {
BasicBlock &BB = *I->getParent();
Module *M = BB.getParent()->getParent();
Type *ArgTypeI = I->getType();
Type *ArgTypeJ = J->getType();
Type *VArgType = getVecTypeForPair(ArgTypeI, ArgTypeJ);
ReplacedOperands[o] = Intrinsic::getDeclaration(M, IID, VArgType);
continue;
} else if ((IID == Intrinsic::powi || IID == Intrinsic::ctlz ||
IID == Intrinsic::cttz) && o == 1) {
// The second argument of powi/ctlz/cttz is a single integer/constant
// and we've already checked that both arguments are equal.
// As a result, we just keep I's second argument.
ReplacedOperands[o] = I->getOperand(o);
continue;
}
} else if (isa<ShuffleVectorInst>(I) && o == NumOperands-1) {
ReplacedOperands[o] = getReplacementShuffleMask(Context, I, J);
continue;
}
ReplacedOperands[o] = getReplacementInput(Context, I, J, o, IBeforeJ);
}
}
// This function creates two values that represent the outputs of the
// original I and J instructions. These are generally vector shuffles
// or extracts. In many cases, these will end up being unused and, thus,
// eliminated by later passes.
void BBVectorize::replaceOutputsOfPair(LLVMContext& Context, Instruction *I,
Instruction *J, Instruction *K,
Instruction *&InsertionPt,
Instruction *&K1, Instruction *&K2) {
if (isa<StoreInst>(I)) {
AA->replaceWithNewValue(I, K);
AA->replaceWithNewValue(J, K);
} else {
Type *IType = I->getType();
Type *JType = J->getType();
VectorType *VType = getVecTypeForPair(IType, JType);
unsigned numElem = VType->getNumElements();
unsigned numElemI = getNumScalarElements(IType);
unsigned numElemJ = getNumScalarElements(JType);
if (IType->isVectorTy()) {
std::vector<Constant*> Mask1(numElemI), Mask2(numElemI);
for (unsigned v = 0; v < numElemI; ++v) {
Mask1[v] = ConstantInt::get(Type::getInt32Ty(Context), v);
Mask2[v] = ConstantInt::get(Type::getInt32Ty(Context), numElemJ+v);
}
K1 = new ShuffleVectorInst(K, UndefValue::get(VType),
ConstantVector::get( Mask1),
getReplacementName(K, false, 1));
} else {
Value *CV0 = ConstantInt::get(Type::getInt32Ty(Context), 0);
K1 = ExtractElementInst::Create(K, CV0,
getReplacementName(K, false, 1));
}
if (JType->isVectorTy()) {
std::vector<Constant*> Mask1(numElemJ), Mask2(numElemJ);
for (unsigned v = 0; v < numElemJ; ++v) {
Mask1[v] = ConstantInt::get(Type::getInt32Ty(Context), v);
Mask2[v] = ConstantInt::get(Type::getInt32Ty(Context), numElemI+v);
}
K2 = new ShuffleVectorInst(K, UndefValue::get(VType),
ConstantVector::get( Mask2),
getReplacementName(K, false, 2));
} else {
Value *CV1 = ConstantInt::get(Type::getInt32Ty(Context), numElem-1);
K2 = ExtractElementInst::Create(K, CV1,
getReplacementName(K, false, 2));
}
K1->insertAfter(K);
K2->insertAfter(K1);
InsertionPt = K2;
}
}
// Move all uses of the function I (including pairing-induced uses) after J.
bool BBVectorize::canMoveUsesOfIAfterJ(BasicBlock &BB,
DenseSet<ValuePair> &LoadMoveSetPairs,
Instruction *I, Instruction *J) {
// Skip to the first instruction past I.
BasicBlock::iterator L = std::next(BasicBlock::iterator(I));
DenseSet<Value *> Users;
AliasSetTracker WriteSet(*AA);
if (I->mayWriteToMemory()) WriteSet.add(I);
for (; cast<Instruction>(L) != J; ++L)
(void) trackUsesOfI(Users, WriteSet, I, L, true, &LoadMoveSetPairs);
assert(cast<Instruction>(L) == J &&
"Tracking has not proceeded far enough to check for dependencies");
// If J is now in the use set of I, then trackUsesOfI will return true
// and we have a dependency cycle (and the fusing operation must abort).
return !trackUsesOfI(Users, WriteSet, I, J, true, &LoadMoveSetPairs);
}
// Move all uses of the function I (including pairing-induced uses) after J.
void BBVectorize::moveUsesOfIAfterJ(BasicBlock &BB,
DenseSet<ValuePair> &LoadMoveSetPairs,
Instruction *&InsertionPt,
Instruction *I, Instruction *J) {
// Skip to the first instruction past I.
BasicBlock::iterator L = std::next(BasicBlock::iterator(I));
DenseSet<Value *> Users;
AliasSetTracker WriteSet(*AA);
if (I->mayWriteToMemory()) WriteSet.add(I);
for (; cast<Instruction>(L) != J;) {
if (trackUsesOfI(Users, WriteSet, I, L, true, &LoadMoveSetPairs)) {
// Move this instruction
Instruction *InstToMove = L; ++L;
DEBUG(dbgs() << "BBV: moving: " << *InstToMove <<
" to after " << *InsertionPt << "\n");
InstToMove->removeFromParent();
InstToMove->insertAfter(InsertionPt);
InsertionPt = InstToMove;
} else {
++L;
}
}
}
// Collect all load instruction that are in the move set of a given first
// pair member. These loads depend on the first instruction, I, and so need
// to be moved after J (the second instruction) when the pair is fused.
void BBVectorize::collectPairLoadMoveSet(BasicBlock &BB,
DenseMap<Value *, Value *> &ChosenPairs,
DenseMap<Value *, std::vector<Value *> > &LoadMoveSet,
DenseSet<ValuePair> &LoadMoveSetPairs,
Instruction *I) {
// Skip to the first instruction past I.
BasicBlock::iterator L = std::next(BasicBlock::iterator(I));
DenseSet<Value *> Users;
AliasSetTracker WriteSet(*AA);
if (I->mayWriteToMemory()) WriteSet.add(I);
// Note: We cannot end the loop when we reach J because J could be moved
// farther down the use chain by another instruction pairing. Also, J
// could be before I if this is an inverted input.
for (BasicBlock::iterator E = BB.end(); cast<Instruction>(L) != E; ++L) {
if (trackUsesOfI(Users, WriteSet, I, L)) {
if (L->mayReadFromMemory()) {
LoadMoveSet[L].push_back(I);
LoadMoveSetPairs.insert(ValuePair(L, I));
}
}
}
}
// In cases where both load/stores and the computation of their pointers
// are chosen for vectorization, we can end up in a situation where the
// aliasing analysis starts returning different query results as the
// process of fusing instruction pairs continues. Because the algorithm
// relies on finding the same use dags here as were found earlier, we'll
// need to precompute the necessary aliasing information here and then
// manually update it during the fusion process.
void BBVectorize::collectLoadMoveSet(BasicBlock &BB,
std::vector<Value *> &PairableInsts,
DenseMap<Value *, Value *> &ChosenPairs,
DenseMap<Value *, std::vector<Value *> > &LoadMoveSet,
DenseSet<ValuePair> &LoadMoveSetPairs) {
for (std::vector<Value *>::iterator PI = PairableInsts.begin(),
PIE = PairableInsts.end(); PI != PIE; ++PI) {
DenseMap<Value *, Value *>::iterator P = ChosenPairs.find(*PI);
if (P == ChosenPairs.end()) continue;
Instruction *I = cast<Instruction>(P->first);
collectPairLoadMoveSet(BB, ChosenPairs, LoadMoveSet,
LoadMoveSetPairs, I);
}
}
// This function fuses the chosen instruction pairs into vector instructions,
// taking care preserve any needed scalar outputs and, then, it reorders the
// remaining instructions as needed (users of the first member of the pair
// need to be moved to after the location of the second member of the pair
// because the vector instruction is inserted in the location of the pair's
// second member).
void BBVectorize::fuseChosenPairs(BasicBlock &BB,
std::vector<Value *> &PairableInsts,
DenseMap<Value *, Value *> &ChosenPairs,
DenseSet<ValuePair> &FixedOrderPairs,
DenseMap<VPPair, unsigned> &PairConnectionTypes,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps) {
LLVMContext& Context = BB.getContext();
// During the vectorization process, the order of the pairs to be fused
// could be flipped. So we'll add each pair, flipped, into the ChosenPairs
// list. After a pair is fused, the flipped pair is removed from the list.
DenseSet<ValuePair> FlippedPairs;
for (DenseMap<Value *, Value *>::iterator P = ChosenPairs.begin(),
E = ChosenPairs.end(); P != E; ++P)
FlippedPairs.insert(ValuePair(P->second, P->first));
for (DenseSet<ValuePair>::iterator P = FlippedPairs.begin(),
E = FlippedPairs.end(); P != E; ++P)
ChosenPairs.insert(*P);
DenseMap<Value *, std::vector<Value *> > LoadMoveSet;
DenseSet<ValuePair> LoadMoveSetPairs;
collectLoadMoveSet(BB, PairableInsts, ChosenPairs,
LoadMoveSet, LoadMoveSetPairs);
DEBUG(dbgs() << "BBV: initial: \n" << BB << "\n");
for (BasicBlock::iterator PI = BB.getFirstInsertionPt(); PI != BB.end();) {
DenseMap<Value *, Value *>::iterator P = ChosenPairs.find(PI);
if (P == ChosenPairs.end()) {
++PI;
continue;
}
if (getDepthFactor(P->first) == 0) {
// These instructions are not really fused, but are tracked as though
// they are. Any case in which it would be interesting to fuse them
// will be taken care of by InstCombine.
--NumFusedOps;
++PI;
continue;
}
Instruction *I = cast<Instruction>(P->first),
*J = cast<Instruction>(P->second);
DEBUG(dbgs() << "BBV: fusing: " << *I <<
" <-> " << *J << "\n");
// Remove the pair and flipped pair from the list.
DenseMap<Value *, Value *>::iterator FP = ChosenPairs.find(P->second);
assert(FP != ChosenPairs.end() && "Flipped pair not found in list");
ChosenPairs.erase(FP);
ChosenPairs.erase(P);
if (!canMoveUsesOfIAfterJ(BB, LoadMoveSetPairs, I, J)) {
DEBUG(dbgs() << "BBV: fusion of: " << *I <<
" <-> " << *J <<
" aborted because of non-trivial dependency cycle\n");
--NumFusedOps;
++PI;
continue;
}
// If the pair must have the other order, then flip it.
bool FlipPairOrder = FixedOrderPairs.count(ValuePair(J, I));
if (!FlipPairOrder && !FixedOrderPairs.count(ValuePair(I, J))) {
// This pair does not have a fixed order, and so we might want to
// flip it if that will yield fewer shuffles. We count the number
// of dependencies connected via swaps, and those directly connected,
// and flip the order if the number of swaps is greater.
bool OrigOrder = true;
DenseMap<ValuePair, std::vector<ValuePair> >::iterator IJ =
ConnectedPairDeps.find(ValuePair(I, J));
if (IJ == ConnectedPairDeps.end()) {
IJ = ConnectedPairDeps.find(ValuePair(J, I));
OrigOrder = false;
}
if (IJ != ConnectedPairDeps.end()) {
unsigned NumDepsDirect = 0, NumDepsSwap = 0;
for (std::vector<ValuePair>::iterator T = IJ->second.begin(),
TE = IJ->second.end(); T != TE; ++T) {
VPPair Q(IJ->first, *T);
DenseMap<VPPair, unsigned>::iterator R =
PairConnectionTypes.find(VPPair(Q.second, Q.first));
assert(R != PairConnectionTypes.end() &&
"Cannot find pair connection type");
if (R->second == PairConnectionDirect)
++NumDepsDirect;
else if (R->second == PairConnectionSwap)
++NumDepsSwap;
}
if (!OrigOrder)
std::swap(NumDepsDirect, NumDepsSwap);
if (NumDepsSwap > NumDepsDirect) {
FlipPairOrder = true;
DEBUG(dbgs() << "BBV: reordering pair: " << *I <<
" <-> " << *J << "\n");
}
}
}
Instruction *L = I, *H = J;
if (FlipPairOrder)
std::swap(H, L);
// If the pair being fused uses the opposite order from that in the pair
// connection map, then we need to flip the types.
DenseMap<ValuePair, std::vector<ValuePair> >::iterator HL =
ConnectedPairs.find(ValuePair(H, L));
if (HL != ConnectedPairs.end())
for (std::vector<ValuePair>::iterator T = HL->second.begin(),
TE = HL->second.end(); T != TE; ++T) {
VPPair Q(HL->first, *T);
DenseMap<VPPair, unsigned>::iterator R = PairConnectionTypes.find(Q);
assert(R != PairConnectionTypes.end() &&
"Cannot find pair connection type");
if (R->second == PairConnectionDirect)
R->second = PairConnectionSwap;
else if (R->second == PairConnectionSwap)
R->second = PairConnectionDirect;
}
bool LBeforeH = !FlipPairOrder;
unsigned NumOperands = I->getNumOperands();
SmallVector<Value *, 3> ReplacedOperands(NumOperands);
getReplacementInputsForPair(Context, L, H, ReplacedOperands,
LBeforeH);
// Make a copy of the original operation, change its type to the vector
// type and replace its operands with the vector operands.
Instruction *K = L->clone();
if (L->hasName())
K->takeName(L);
else if (H->hasName())
K->takeName(H);
if (auto CS = CallSite(K)) {
SmallVector<Type *, 3> Tys;
FunctionType *Old = CS.getFunctionType();
unsigned NumOld = Old->getNumParams();
assert(NumOld <= ReplacedOperands.size());
for (unsigned i = 0; i != NumOld; ++i)
Tys.push_back(ReplacedOperands[i]->getType());
CS.mutateFunctionType(
FunctionType::get(getVecTypeForPair(L->getType(), H->getType()),
Tys, Old->isVarArg()));
} else if (!isa<StoreInst>(K))
K->mutateType(getVecTypeForPair(L->getType(), H->getType()));
unsigned KnownIDs[] = {
LLVMContext::MD_tbaa,
LLVMContext::MD_alias_scope,
LLVMContext::MD_noalias,
LLVMContext::MD_fpmath
};
combineMetadata(K, H, KnownIDs);
K->intersectOptionalDataWith(H);
for (unsigned o = 0; o < NumOperands; ++o)
K->setOperand(o, ReplacedOperands[o]);
K->insertAfter(J);
// Instruction insertion point:
Instruction *InsertionPt = K;
Instruction *K1 = nullptr, *K2 = nullptr;
replaceOutputsOfPair(Context, L, H, K, InsertionPt, K1, K2);
// The use dag of the first original instruction must be moved to after
// the location of the second instruction. The entire use dag of the
// first instruction is disjoint from the input dag of the second
// (by definition), and so commutes with it.
moveUsesOfIAfterJ(BB, LoadMoveSetPairs, InsertionPt, I, J);
if (!isa<StoreInst>(I)) {
L->replaceAllUsesWith(K1);
H->replaceAllUsesWith(K2);
AA->replaceWithNewValue(L, K1);
AA->replaceWithNewValue(H, K2);
}
// Instructions that may read from memory may be in the load move set.
// Once an instruction is fused, we no longer need its move set, and so
// the values of the map never need to be updated. However, when a load
// is fused, we need to merge the entries from both instructions in the
// pair in case those instructions were in the move set of some other
// yet-to-be-fused pair. The loads in question are the keys of the map.
if (I->mayReadFromMemory()) {
std::vector<ValuePair> NewSetMembers;
DenseMap<Value *, std::vector<Value *> >::iterator II =
LoadMoveSet.find(I);
if (II != LoadMoveSet.end())
for (std::vector<Value *>::iterator N = II->second.begin(),
NE = II->second.end(); N != NE; ++N)
NewSetMembers.push_back(ValuePair(K, *N));
DenseMap<Value *, std::vector<Value *> >::iterator JJ =
LoadMoveSet.find(J);
if (JJ != LoadMoveSet.end())
for (std::vector<Value *>::iterator N = JJ->second.begin(),
NE = JJ->second.end(); N != NE; ++N)
NewSetMembers.push_back(ValuePair(K, *N));
for (std::vector<ValuePair>::iterator A = NewSetMembers.begin(),
AE = NewSetMembers.end(); A != AE; ++A) {
LoadMoveSet[A->first].push_back(A->second);
LoadMoveSetPairs.insert(*A);
}
}
// Before removing I, set the iterator to the next instruction.
PI = std::next(BasicBlock::iterator(I));
if (cast<Instruction>(PI) == J)
++PI;
SE->forgetValue(I);
SE->forgetValue(J);
I->eraseFromParent();
J->eraseFromParent();
DEBUG(if (PrintAfterEveryPair) dbgs() << "BBV: block is now: \n" <<
BB << "\n");
}
DEBUG(dbgs() << "BBV: final: \n" << BB << "\n");
}
}
char BBVectorize::ID = 0;
static const char bb_vectorize_name[] = "Basic-Block Vectorization";
INITIALIZE_PASS_BEGIN(BBVectorize, BBV_NAME, bb_vectorize_name, false, false)
INITIALIZE_AG_DEPENDENCY(AliasAnalysis)
INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_DEPENDENCY(ScalarEvolution)
INITIALIZE_PASS_END(BBVectorize, BBV_NAME, bb_vectorize_name, false, false)
BasicBlockPass *llvm::createBBVectorizePass(const VectorizeConfig &C) {
return new BBVectorize(C);
}
bool
llvm::vectorizeBasicBlock(Pass *P, BasicBlock &BB, const VectorizeConfig &C) {
BBVectorize BBVectorizer(P, *BB.getParent(), C);
return BBVectorizer.vectorizeBB(BB);
}
//===----------------------------------------------------------------------===//
VectorizeConfig::VectorizeConfig() {
VectorBits = ::VectorBits;
VectorizeBools = !::NoBools;
VectorizeInts = !::NoInts;
VectorizeFloats = !::NoFloats;
VectorizePointers = !::NoPointers;
VectorizeCasts = !::NoCasts;
VectorizeMath = !::NoMath;
VectorizeBitManipulations = !::NoBitManipulation;
VectorizeFMA = !::NoFMA;
VectorizeSelect = !::NoSelect;
VectorizeCmp = !::NoCmp;
VectorizeGEP = !::NoGEP;
VectorizeMemOps = !::NoMemOps;
AlignedOnly = ::AlignedOnly;
ReqChainDepth= ::ReqChainDepth;
SearchLimit = ::SearchLimit;
MaxCandPairsForCycleCheck = ::MaxCandPairsForCycleCheck;
SplatBreaksChain = ::SplatBreaksChain;
MaxInsts = ::MaxInsts;
MaxPairs = ::MaxPairs;
MaxIter = ::MaxIter;
Pow2LenOnly = ::Pow2LenOnly;
NoMemOpBoost = ::NoMemOpBoost;
FastDep = ::FastDep;
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Vectorize/LoopVectorize.cpp | //===- LoopVectorize.cpp - A Loop Vectorizer ------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This is the LLVM loop vectorizer. This pass modifies 'vectorizable' loops
// and generates target-independent LLVM-IR.
// The vectorizer uses the TargetTransformInfo analysis to estimate the costs
// of instructions in order to estimate the profitability of vectorization.
//
// The loop vectorizer combines consecutive loop iterations into a single
// 'wide' iteration. After this transformation the index is incremented
// by the SIMD vector width, and not by one.
//
// This pass has three parts:
// 1. The main loop pass that drives the different parts.
// 2. LoopVectorizationLegality - A unit that checks for the legality
// of the vectorization.
// 3. InnerLoopVectorizer - A unit that performs the actual
// widening of instructions.
// 4. LoopVectorizationCostModel - A unit that checks for the profitability
// of vectorization. It decides on the optimal vector width, which
// can be one, if vectorization is not profitable.
//
//===----------------------------------------------------------------------===//
//
// The reduction-variable vectorization is based on the paper:
// D. Nuzman and R. Henderson. Multi-platform Auto-vectorization.
//
// Variable uniformity checks are inspired by:
// Karrenberg, R. and Hack, S. Whole Function Vectorization.
//
// The interleaved access vectorization is based on the paper:
// Dorit Nuzman, Ira Rosen and Ayal Zaks. Auto-Vectorization of Interleaved
// Data for SIMD
//
// Other ideas/concepts are from:
// A. Zaks and D. Nuzman. Autovectorization in GCC-two years later.
//
// S. Maleki, Y. Gao, M. Garzaran, T. Wong and D. Padua. An Evaluation of
// Vectorizing Compilers.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Vectorize.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/EquivalenceClasses.h"
#include "llvm/ADT/Hashing.h"
#include "llvm/ADT/MapVector.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/AliasSetTracker.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/BlockFrequencyInfo.h"
#include "llvm/Analysis/CodeMetrics.h"
#include "llvm/Analysis/LoopAccessAnalysis.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/LoopIterator.h"
#include "llvm/Analysis/LoopPass.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/ScalarEvolutionExpander.h"
#include "llvm/Analysis/ScalarEvolutionExpressions.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/DiagnosticInfo.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/Value.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/IR/Verifier.h"
#include "llvm/Pass.h"
#include "llvm/Support/BranchProbability.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Analysis/VectorUtils.h"
#include "llvm/Transforms/Utils/LoopUtils.h"
#include <algorithm>
#include <map>
#include <tuple>
using namespace llvm;
using namespace llvm::PatternMatch;
#define LV_NAME "loop-vectorize"
#define DEBUG_TYPE LV_NAME
STATISTIC(LoopsVectorized, "Number of loops vectorized");
STATISTIC(LoopsAnalyzed, "Number of loops analyzed for vectorization");
static cl::opt<bool>
EnableIfConversion("enable-if-conversion", cl::init(true), cl::Hidden,
cl::desc("Enable if-conversion during vectorization."));
/// We don't vectorize loops with a known constant trip count below this number.
static cl::opt<unsigned>
TinyTripCountVectorThreshold("vectorizer-min-trip-count", cl::init(16),
cl::Hidden,
cl::desc("Don't vectorize loops with a constant "
"trip count that is smaller than this "
"value."));
/// This enables versioning on the strides of symbolically striding memory
/// accesses in code like the following.
/// for (i = 0; i < N; ++i)
/// A[i * Stride1] += B[i * Stride2] ...
///
/// Will be roughly translated to
/// if (Stride1 == 1 && Stride2 == 1) {
/// for (i = 0; i < N; i+=4)
/// A[i:i+3] += ...
/// } else
/// ...
static cl::opt<bool> EnableMemAccessVersioning(
"enable-mem-access-versioning", cl::init(true), cl::Hidden,
cl::desc("Enable symblic stride memory access versioning"));
static cl::opt<bool> EnableInterleavedMemAccesses(
"enable-interleaved-mem-accesses", cl::init(false), cl::Hidden,
cl::desc("Enable vectorization on interleaved memory accesses in a loop"));
/// Maximum factor for an interleaved memory access.
static cl::opt<unsigned> MaxInterleaveGroupFactor(
"max-interleave-group-factor", cl::Hidden,
cl::desc("Maximum factor for an interleaved access group (default = 8)"),
cl::init(8));
/// We don't interleave loops with a known constant trip count below this
/// number.
static const unsigned TinyTripCountInterleaveThreshold = 128;
static cl::opt<unsigned> ForceTargetNumScalarRegs(
"force-target-num-scalar-regs", cl::init(0), cl::Hidden,
cl::desc("A flag that overrides the target's number of scalar registers."));
static cl::opt<unsigned> ForceTargetNumVectorRegs(
"force-target-num-vector-regs", cl::init(0), cl::Hidden,
cl::desc("A flag that overrides the target's number of vector registers."));
/// Maximum vectorization interleave count.
static const unsigned MaxInterleaveFactor = 16;
static cl::opt<unsigned> ForceTargetMaxScalarInterleaveFactor(
"force-target-max-scalar-interleave", cl::init(0), cl::Hidden,
cl::desc("A flag that overrides the target's max interleave factor for "
"scalar loops."));
static cl::opt<unsigned> ForceTargetMaxVectorInterleaveFactor(
"force-target-max-vector-interleave", cl::init(0), cl::Hidden,
cl::desc("A flag that overrides the target's max interleave factor for "
"vectorized loops."));
static cl::opt<unsigned> ForceTargetInstructionCost(
"force-target-instruction-cost", cl::init(0), cl::Hidden,
cl::desc("A flag that overrides the target's expected cost for "
"an instruction to a single constant value. Mostly "
"useful for getting consistent testing."));
static cl::opt<unsigned> SmallLoopCost(
"small-loop-cost", cl::init(20), cl::Hidden,
cl::desc(
"The cost of a loop that is considered 'small' by the interleaver."));
static cl::opt<bool> LoopVectorizeWithBlockFrequency(
"loop-vectorize-with-block-frequency", cl::init(false), cl::Hidden,
cl::desc("Enable the use of the block frequency analysis to access PGO "
"heuristics minimizing code growth in cold regions and being more "
"aggressive in hot regions."));
// Runtime interleave loops for load/store throughput.
static cl::opt<bool> EnableLoadStoreRuntimeInterleave(
"enable-loadstore-runtime-interleave", cl::init(true), cl::Hidden,
cl::desc(
"Enable runtime interleaving until load/store ports are saturated"));
/// The number of stores in a loop that are allowed to need predication.
static cl::opt<unsigned> NumberOfStoresToPredicate(
"vectorize-num-stores-pred", cl::init(1), cl::Hidden,
cl::desc("Max number of stores to be predicated behind an if."));
static cl::opt<bool> EnableIndVarRegisterHeur(
"enable-ind-var-reg-heur", cl::init(true), cl::Hidden,
cl::desc("Count the induction variable only once when interleaving"));
static cl::opt<bool> EnableCondStoresVectorization(
"enable-cond-stores-vec", cl::init(false), cl::Hidden,
cl::desc("Enable if predication of stores during vectorization."));
static cl::opt<unsigned> MaxNestedScalarReductionIC(
"max-nested-scalar-reduction-interleave", cl::init(2), cl::Hidden,
cl::desc("The maximum interleave count to use when interleaving a scalar "
"reduction in a nested loop."));
namespace {
// Forward declarations.
class LoopVectorizationLegality;
class LoopVectorizationCostModel;
class LoopVectorizeHints;
/// \brief This modifies LoopAccessReport to initialize message with
/// loop-vectorizer-specific part.
class VectorizationReport : public LoopAccessReport {
public:
VectorizationReport(Instruction *I = nullptr)
: LoopAccessReport("loop not vectorized: ", I) {}
/// \brief This allows promotion of the loop-access analysis report into the
/// loop-vectorizer report. It modifies the message to add the
/// loop-vectorizer-specific part of the message.
explicit VectorizationReport(const LoopAccessReport &R)
: LoopAccessReport(Twine("loop not vectorized: ") + R.str(),
R.getInstr()) {}
};
/// A helper function for converting Scalar types to vector types.
/// If the incoming type is void, we return void. If the VF is 1, we return
/// the scalar type.
static Type* ToVectorTy(Type *Scalar, unsigned VF) {
if (Scalar->isVoidTy() || VF == 1)
return Scalar;
return VectorType::get(Scalar, VF);
}
/// InnerLoopVectorizer vectorizes loops which contain only one basic
/// block to a specified vectorization factor (VF).
/// This class performs the widening of scalars into vectors, or multiple
/// scalars. This class also implements the following features:
/// * It inserts an epilogue loop for handling loops that don't have iteration
/// counts that are known to be a multiple of the vectorization factor.
/// * It handles the code generation for reduction variables.
/// * Scalarization (implementation using scalars) of un-vectorizable
/// instructions.
/// InnerLoopVectorizer does not perform any vectorization-legality
/// checks, and relies on the caller to check for the different legality
/// aspects. The InnerLoopVectorizer relies on the
/// LoopVectorizationLegality class to provide information about the induction
/// and reduction variables that were found to a given vectorization factor.
class InnerLoopVectorizer {
public:
InnerLoopVectorizer(Loop *OrigLoop, ScalarEvolution *SE, LoopInfo *LI,
DominatorTree *DT, const TargetLibraryInfo *TLI,
const TargetTransformInfo *TTI, unsigned VecWidth,
unsigned UnrollFactor)
: OrigLoop(OrigLoop), SE(SE), LI(LI), DT(DT), TLI(TLI), TTI(TTI),
VF(VecWidth), UF(UnrollFactor), Builder(SE->getContext()),
Induction(nullptr), OldInduction(nullptr), WidenMap(UnrollFactor),
Legal(nullptr), AddedSafetyChecks(false) {}
// Perform the actual loop widening (vectorization).
void vectorize(LoopVectorizationLegality *L) {
Legal = L;
// Create a new empty loop. Unlink the old loop and connect the new one.
createEmptyLoop();
// Widen each instruction in the old loop to a new one in the new loop.
// Use the Legality module to find the induction and reduction variables.
vectorizeLoop();
// Register the new loop and update the analysis passes.
updateAnalysis();
}
// Return true if any runtime check is added.
bool IsSafetyChecksAdded() {
return AddedSafetyChecks;
}
virtual ~InnerLoopVectorizer() {}
protected:
/// A small list of PHINodes.
typedef SmallVector<PHINode*, 4> PhiVector;
/// When we unroll loops we have multiple vector values for each scalar.
/// This data structure holds the unrolled and vectorized values that
/// originated from one scalar instruction.
typedef SmallVector<Value*, 2> VectorParts;
// When we if-convert we need to create edge masks. We have to cache values
// so that we don't end up with exponential recursion/IR.
typedef DenseMap<std::pair<BasicBlock*, BasicBlock*>,
VectorParts> EdgeMaskCache;
/// \brief Add checks for strides that were assumed to be 1.
///
/// Returns the last check instruction and the first check instruction in the
/// pair as (first, last).
std::pair<Instruction *, Instruction *> addStrideCheck(Instruction *Loc);
/// Create an empty loop, based on the loop ranges of the old loop.
void createEmptyLoop();
/// Copy and widen the instructions from the old loop.
virtual void vectorizeLoop();
/// \brief The Loop exit block may have single value PHI nodes where the
/// incoming value is 'Undef'. While vectorizing we only handled real values
/// that were defined inside the loop. Here we fix the 'undef case'.
/// See PR14725.
void fixLCSSAPHIs();
/// A helper function that computes the predicate of the block BB, assuming
/// that the header block of the loop is set to True. It returns the *entry*
/// mask for the block BB.
VectorParts createBlockInMask(BasicBlock *BB);
/// A helper function that computes the predicate of the edge between SRC
/// and DST.
VectorParts createEdgeMask(BasicBlock *Src, BasicBlock *Dst);
/// A helper function to vectorize a single BB within the innermost loop.
void vectorizeBlockInLoop(BasicBlock *BB, PhiVector *PV);
/// Vectorize a single PHINode in a block. This method handles the induction
/// variable canonicalization. It supports both VF = 1 for unrolled loops and
/// arbitrary length vectors.
void widenPHIInstruction(Instruction *PN, VectorParts &Entry,
unsigned UF, unsigned VF, PhiVector *PV);
/// Insert the new loop to the loop hierarchy and pass manager
/// and update the analysis passes.
void updateAnalysis();
/// This instruction is un-vectorizable. Implement it as a sequence
/// of scalars. If \p IfPredicateStore is true we need to 'hide' each
/// scalarized instruction behind an if block predicated on the control
/// dependence of the instruction.
virtual void scalarizeInstruction(Instruction *Instr,
bool IfPredicateStore=false);
/// Vectorize Load and Store instructions,
virtual void vectorizeMemoryInstruction(Instruction *Instr);
/// Create a broadcast instruction. This method generates a broadcast
/// instruction (shuffle) for loop invariant values and for the induction
/// value. If this is the induction variable then we extend it to N, N+1, ...
/// this is needed because each iteration in the loop corresponds to a SIMD
/// element.
virtual Value *getBroadcastInstrs(Value *V);
/// This function adds (StartIdx, StartIdx + Step, StartIdx + 2*Step, ...)
/// to each vector element of Val. The sequence starts at StartIndex.
virtual Value *getStepVector(Value *Val, int StartIdx, Value *Step);
/// When we go over instructions in the basic block we rely on previous
/// values within the current basic block or on loop invariant values.
/// When we widen (vectorize) values we place them in the map. If the values
/// are not within the map, they have to be loop invariant, so we simply
/// broadcast them into a vector.
VectorParts &getVectorValue(Value *V);
/// Try to vectorize the interleaved access group that \p Instr belongs to.
void vectorizeInterleaveGroup(Instruction *Instr);
/// Generate a shuffle sequence that will reverse the vector Vec.
virtual Value *reverseVector(Value *Vec);
/// This is a helper class that holds the vectorizer state. It maps scalar
/// instructions to vector instructions. When the code is 'unrolled' then
/// then a single scalar value is mapped to multiple vector parts. The parts
/// are stored in the VectorPart type.
struct ValueMap {
/// C'tor. UnrollFactor controls the number of vectors ('parts') that
/// are mapped.
ValueMap(unsigned UnrollFactor) : UF(UnrollFactor) {}
/// \return True if 'Key' is saved in the Value Map.
bool has(Value *Key) const { return MapStorage.count(Key); }
/// Initializes a new entry in the map. Sets all of the vector parts to the
/// save value in 'Val'.
/// \return A reference to a vector with splat values.
VectorParts &splat(Value *Key, Value *Val) {
VectorParts &Entry = MapStorage[Key];
Entry.assign(UF, Val);
return Entry;
}
///\return A reference to the value that is stored at 'Key'.
VectorParts &get(Value *Key) {
VectorParts &Entry = MapStorage[Key];
if (Entry.empty())
Entry.resize(UF);
assert(Entry.size() == UF);
return Entry;
}
private:
/// The unroll factor. Each entry in the map stores this number of vector
/// elements.
unsigned UF;
/// Map storage. We use std::map and not DenseMap because insertions to a
/// dense map invalidates its iterators.
std::map<Value *, VectorParts> MapStorage;
};
/// The original loop.
Loop *OrigLoop;
/// Scev analysis to use.
ScalarEvolution *SE;
/// Loop Info.
LoopInfo *LI;
/// Dominator Tree.
DominatorTree *DT;
/// Alias Analysis.
AliasAnalysis *AA;
/// Target Library Info.
const TargetLibraryInfo *TLI;
/// Target Transform Info.
const TargetTransformInfo *TTI;
/// The vectorization SIMD factor to use. Each vector will have this many
/// vector elements.
unsigned VF;
protected:
/// The vectorization unroll factor to use. Each scalar is vectorized to this
/// many different vector instructions.
unsigned UF;
/// The builder that we use
IRBuilder<> Builder;
// --- Vectorization state ---
/// The vector-loop preheader.
BasicBlock *LoopVectorPreHeader;
/// The scalar-loop preheader.
BasicBlock *LoopScalarPreHeader;
/// Middle Block between the vector and the scalar.
BasicBlock *LoopMiddleBlock;
///The ExitBlock of the scalar loop.
BasicBlock *LoopExitBlock;
///The vector loop body.
SmallVector<BasicBlock *, 4> LoopVectorBody;
///The scalar loop body.
BasicBlock *LoopScalarBody;
/// A list of all bypass blocks. The first block is the entry of the loop.
SmallVector<BasicBlock *, 4> LoopBypassBlocks;
/// The new Induction variable which was added to the new block.
PHINode *Induction;
/// The induction variable of the old basic block.
PHINode *OldInduction;
/// Holds the extended (to the widest induction type) start index.
Value *ExtendedIdx;
/// Maps scalars to widened vectors.
ValueMap WidenMap;
EdgeMaskCache MaskCache;
LoopVectorizationLegality *Legal;
// Record whether runtime check is added.
bool AddedSafetyChecks;
};
class InnerLoopUnroller : public InnerLoopVectorizer {
public:
InnerLoopUnroller(Loop *OrigLoop, ScalarEvolution *SE, LoopInfo *LI,
DominatorTree *DT, const TargetLibraryInfo *TLI,
const TargetTransformInfo *TTI, unsigned UnrollFactor)
: InnerLoopVectorizer(OrigLoop, SE, LI, DT, TLI, TTI, 1, UnrollFactor) {}
private:
void scalarizeInstruction(Instruction *Instr,
bool IfPredicateStore = false) override;
void vectorizeMemoryInstruction(Instruction *Instr) override;
Value *getBroadcastInstrs(Value *V) override;
Value *getStepVector(Value *Val, int StartIdx, Value *Step) override;
Value *reverseVector(Value *Vec) override;
};
/// \brief Look for a meaningful debug location on the instruction or it's
/// operands.
static Instruction *getDebugLocFromInstOrOperands(Instruction *I) {
if (!I)
return I;
DebugLoc Empty;
if (I->getDebugLoc() != Empty)
return I;
for (User::op_iterator OI = I->op_begin(), OE = I->op_end(); OI != OE; ++OI) {
if (Instruction *OpInst = dyn_cast<Instruction>(*OI))
if (OpInst->getDebugLoc() != Empty)
return OpInst;
}
return I;
}
/// \brief Set the debug location in the builder using the debug location in the
/// instruction.
static void setDebugLocFromInst(IRBuilder<> &B, const Value *Ptr) {
if (const Instruction *Inst = dyn_cast_or_null<Instruction>(Ptr))
B.SetCurrentDebugLocation(Inst->getDebugLoc());
else
B.SetCurrentDebugLocation(DebugLoc());
}
#ifndef NDEBUG
/// \return string containing a file name and a line # for the given loop.
static std::string getDebugLocString(const Loop *L) {
std::string Result;
if (L) {
raw_string_ostream OS(Result);
if (const DebugLoc LoopDbgLoc = L->getStartLoc())
LoopDbgLoc.print(OS);
else
// Just print the module name.
OS << L->getHeader()->getParent()->getParent()->getModuleIdentifier();
OS.flush();
}
return Result;
}
#endif
/// \brief Propagate known metadata from one instruction to another.
static void propagateMetadata(Instruction *To, const Instruction *From) {
SmallVector<std::pair<unsigned, MDNode *>, 4> Metadata;
From->getAllMetadataOtherThanDebugLoc(Metadata);
for (auto M : Metadata) {
unsigned Kind = M.first;
// These are safe to transfer (this is safe for TBAA, even when we
// if-convert, because should that metadata have had a control dependency
// on the condition, and thus actually aliased with some other
// non-speculated memory access when the condition was false, this would be
// caught by the runtime overlap checks).
if (Kind != LLVMContext::MD_tbaa &&
Kind != LLVMContext::MD_alias_scope &&
Kind != LLVMContext::MD_noalias &&
Kind != LLVMContext::MD_fpmath)
continue;
To->setMetadata(Kind, M.second);
}
}
/// \brief Propagate known metadata from one instruction to a vector of others.
static void propagateMetadata(SmallVectorImpl<Value *> &To, const Instruction *From) {
for (Value *V : To)
if (Instruction *I = dyn_cast<Instruction>(V))
propagateMetadata(I, From);
}
/// \brief The group of interleaved loads/stores sharing the same stride and
/// close to each other.
///
/// Each member in this group has an index starting from 0, and the largest
/// index should be less than interleaved factor, which is equal to the absolute
/// value of the access's stride.
///
/// E.g. An interleaved load group of factor 4:
/// for (unsigned i = 0; i < 1024; i+=4) {
/// a = A[i]; // Member of index 0
/// b = A[i+1]; // Member of index 1
/// d = A[i+3]; // Member of index 3
/// ...
/// }
///
/// An interleaved store group of factor 4:
/// for (unsigned i = 0; i < 1024; i+=4) {
/// ...
/// A[i] = a; // Member of index 0
/// A[i+1] = b; // Member of index 1
/// A[i+2] = c; // Member of index 2
/// A[i+3] = d; // Member of index 3
/// }
///
/// Note: the interleaved load group could have gaps (missing members), but
/// the interleaved store group doesn't allow gaps.
class InterleaveGroup {
public:
InterleaveGroup(Instruction *Instr, int Stride, unsigned Align)
: Align(Align), SmallestKey(0), LargestKey(0), InsertPos(Instr) {
assert(Align && "The alignment should be non-zero");
Factor = std::abs(Stride);
assert(Factor > 1 && "Invalid interleave factor");
Reverse = Stride < 0;
Members[0] = Instr;
}
bool isReverse() const { return Reverse; }
unsigned getFactor() const { return Factor; }
unsigned getAlignment() const { return Align; }
unsigned getNumMembers() const { return Members.size(); }
/// \brief Try to insert a new member \p Instr with index \p Index and
/// alignment \p NewAlign. The index is related to the leader and it could be
/// negative if it is the new leader.
///
/// \returns false if the instruction doesn't belong to the group.
bool insertMember(Instruction *Instr, int Index, unsigned NewAlign) {
assert(NewAlign && "The new member's alignment should be non-zero");
int Key = Index + SmallestKey;
// Skip if there is already a member with the same index.
if (Members.count(Key))
return false;
if (Key > LargestKey) {
// The largest index is always less than the interleave factor.
if (Index >= static_cast<int>(Factor))
return false;
LargestKey = Key;
} else if (Key < SmallestKey) {
// The largest index is always less than the interleave factor.
if (LargestKey - Key >= static_cast<int>(Factor))
return false;
SmallestKey = Key;
}
// It's always safe to select the minimum alignment.
Align = std::min(Align, NewAlign);
Members[Key] = Instr;
return true;
}
/// \brief Get the member with the given index \p Index
///
/// \returns nullptr if contains no such member.
Instruction *getMember(unsigned Index) const {
int Key = SmallestKey + Index;
if (!Members.count(Key))
return nullptr;
return Members.find(Key)->second;
}
/// \brief Get the index for the given member. Unlike the key in the member
/// map, the index starts from 0.
unsigned getIndex(Instruction *Instr) const {
for (auto I : Members)
if (I.second == Instr)
return I.first - SmallestKey;
llvm_unreachable("InterleaveGroup contains no such member");
}
Instruction *getInsertPos() const { return InsertPos; }
void setInsertPos(Instruction *Inst) { InsertPos = Inst; }
private:
unsigned Factor; // Interleave Factor.
bool Reverse;
unsigned Align;
DenseMap<int, Instruction *> Members;
int SmallestKey;
int LargestKey;
// To avoid breaking dependences, vectorized instructions of an interleave
// group should be inserted at either the first load or the last store in
// program order.
//
// E.g. %even = load i32 // Insert Position
// %add = add i32 %even // Use of %even
// %odd = load i32
//
// store i32 %even
// %odd = add i32 // Def of %odd
// store i32 %odd // Insert Position
Instruction *InsertPos;
};
/// \brief Drive the analysis of interleaved memory accesses in the loop.
///
/// Use this class to analyze interleaved accesses only when we can vectorize
/// a loop. Otherwise it's meaningless to do analysis as the vectorization
/// on interleaved accesses is unsafe.
///
/// The analysis collects interleave groups and records the relationships
/// between the member and the group in a map.
class InterleavedAccessInfo {
public:
InterleavedAccessInfo(ScalarEvolution *SE, Loop *L, DominatorTree *DT)
: SE(SE), TheLoop(L), DT(DT) {}
~InterleavedAccessInfo() {
SmallSet<InterleaveGroup *, 4> DelSet;
// Avoid releasing a pointer twice.
for (auto &I : InterleaveGroupMap)
DelSet.insert(I.second);
for (auto *Ptr : DelSet)
delete Ptr;
}
/// \brief Analyze the interleaved accesses and collect them in interleave
/// groups. Substitute symbolic strides using \p Strides.
void analyzeInterleaving(const ValueToValueMap &Strides);
/// \brief Check if \p Instr belongs to any interleave group.
bool isInterleaved(Instruction *Instr) const {
return InterleaveGroupMap.count(Instr);
}
/// \brief Get the interleave group that \p Instr belongs to.
///
/// \returns nullptr if doesn't have such group.
InterleaveGroup *getInterleaveGroup(Instruction *Instr) const {
if (InterleaveGroupMap.count(Instr))
return InterleaveGroupMap.find(Instr)->second;
return nullptr;
}
private:
ScalarEvolution *SE;
Loop *TheLoop;
DominatorTree *DT;
/// Holds the relationships between the members and the interleave group.
DenseMap<Instruction *, InterleaveGroup *> InterleaveGroupMap;
/// \brief The descriptor for a strided memory access.
struct StrideDescriptor {
StrideDescriptor(int Stride, const SCEV *Scev, unsigned Size,
unsigned Align)
: Stride(Stride), Scev(Scev), Size(Size), Align(Align) {}
StrideDescriptor() : Stride(0), Scev(nullptr), Size(0), Align(0) {}
int Stride; // The access's stride. It is negative for a reverse access.
const SCEV *Scev; // The scalar expression of this access
unsigned Size; // The size of the memory object.
unsigned Align; // The alignment of this access.
};
/// \brief Create a new interleave group with the given instruction \p Instr,
/// stride \p Stride and alignment \p Align.
///
/// \returns the newly created interleave group.
InterleaveGroup *createInterleaveGroup(Instruction *Instr, int Stride,
unsigned Align) {
assert(!InterleaveGroupMap.count(Instr) &&
"Already in an interleaved access group");
InterleaveGroupMap[Instr] = new InterleaveGroup(Instr, Stride, Align);
return InterleaveGroupMap[Instr];
}
/// \brief Release the group and remove all the relationships.
void releaseGroup(InterleaveGroup *Group) {
for (unsigned i = 0; i < Group->getFactor(); i++)
if (Instruction *Member = Group->getMember(i))
InterleaveGroupMap.erase(Member);
delete Group;
}
/// \brief Collect all the accesses with a constant stride in program order.
void collectConstStridedAccesses(
MapVector<Instruction *, StrideDescriptor> &StrideAccesses,
const ValueToValueMap &Strides);
};
/// LoopVectorizationLegality checks if it is legal to vectorize a loop, and
/// to what vectorization factor.
/// This class does not look at the profitability of vectorization, only the
/// legality. This class has two main kinds of checks:
/// * Memory checks - The code in canVectorizeMemory checks if vectorization
/// will change the order of memory accesses in a way that will change the
/// correctness of the program.
/// * Scalars checks - The code in canVectorizeInstrs and canVectorizeMemory
/// checks for a number of different conditions, such as the availability of a
/// single induction variable, that all types are supported and vectorize-able,
/// etc. This code reflects the capabilities of InnerLoopVectorizer.
/// This class is also used by InnerLoopVectorizer for identifying
/// induction variable and the different reduction variables.
class LoopVectorizationLegality {
public:
LoopVectorizationLegality(Loop *L, ScalarEvolution *SE, DominatorTree *DT,
TargetLibraryInfo *TLI, AliasAnalysis *AA,
Function *F, const TargetTransformInfo *TTI,
LoopAccessAnalysis *LAA)
: NumPredStores(0), TheLoop(L), SE(SE), TLI(TLI), TheFunction(F),
TTI(TTI), DT(DT), LAA(LAA), LAI(nullptr), InterleaveInfo(SE, L, DT),
Induction(nullptr), WidestIndTy(nullptr), HasFunNoNaNAttr(false) {}
/// This enum represents the kinds of inductions that we support.
enum InductionKind {
IK_NoInduction, ///< Not an induction variable.
IK_IntInduction, ///< Integer induction variable. Step = C.
IK_PtrInduction ///< Pointer induction var. Step = C / sizeof(elem).
};
/// A struct for saving information about induction variables.
struct InductionInfo {
InductionInfo(Value *Start, InductionKind K, ConstantInt *Step)
: StartValue(Start), IK(K), StepValue(Step) {
assert(IK != IK_NoInduction && "Not an induction");
assert(StartValue && "StartValue is null");
assert(StepValue && !StepValue->isZero() && "StepValue is zero");
assert((IK != IK_PtrInduction || StartValue->getType()->isPointerTy()) &&
"StartValue is not a pointer for pointer induction");
assert((IK != IK_IntInduction || StartValue->getType()->isIntegerTy()) &&
"StartValue is not an integer for integer induction");
assert(StepValue->getType()->isIntegerTy() &&
"StepValue is not an integer");
}
InductionInfo()
: StartValue(nullptr), IK(IK_NoInduction), StepValue(nullptr) {}
/// Get the consecutive direction. Returns:
/// 0 - unknown or non-consecutive.
/// 1 - consecutive and increasing.
/// -1 - consecutive and decreasing.
int getConsecutiveDirection() const {
if (StepValue && (StepValue->isOne() || StepValue->isMinusOne()))
return StepValue->getSExtValue();
return 0;
}
/// Compute the transformed value of Index at offset StartValue using step
/// StepValue.
/// For integer induction, returns StartValue + Index * StepValue.
/// For pointer induction, returns StartValue[Index * StepValue].
/// FIXME: The newly created binary instructions should contain nsw/nuw
/// flags, which can be found from the original scalar operations.
Value *transform(IRBuilder<> &B, Value *Index) const {
switch (IK) {
case IK_IntInduction:
assert(Index->getType() == StartValue->getType() &&
"Index type does not match StartValue type");
if (StepValue->isMinusOne())
return B.CreateSub(StartValue, Index);
if (!StepValue->isOne())
Index = B.CreateMul(Index, StepValue);
return B.CreateAdd(StartValue, Index);
case IK_PtrInduction:
assert(Index->getType() == StepValue->getType() &&
"Index type does not match StepValue type");
if (StepValue->isMinusOne())
Index = B.CreateNeg(Index);
else if (!StepValue->isOne())
Index = B.CreateMul(Index, StepValue);
return B.CreateGEP(nullptr, StartValue, Index);
case IK_NoInduction:
return nullptr;
}
llvm_unreachable("invalid enum");
}
/// Start value.
TrackingVH<Value> StartValue;
/// Induction kind.
InductionKind IK;
/// Step value.
ConstantInt *StepValue;
};
/// ReductionList contains the reduction descriptors for all
/// of the reductions that were found in the loop.
typedef DenseMap<PHINode *, RecurrenceDescriptor> ReductionList;
/// InductionList saves induction variables and maps them to the
/// induction descriptor.
typedef MapVector<PHINode*, InductionInfo> InductionList;
/// Returns true if it is legal to vectorize this loop.
/// This does not mean that it is profitable to vectorize this
/// loop, only that it is legal to do so.
bool canVectorize();
/// Returns the Induction variable.
PHINode *getInduction() { return Induction; }
/// Returns the reduction variables found in the loop.
ReductionList *getReductionVars() { return &Reductions; }
/// Returns the induction variables found in the loop.
InductionList *getInductionVars() { return &Inductions; }
/// Returns the widest induction type.
Type *getWidestInductionType() { return WidestIndTy; }
/// Returns True if V is an induction variable in this loop.
bool isInductionVariable(const Value *V);
/// Return true if the block BB needs to be predicated in order for the loop
/// to be vectorized.
bool blockNeedsPredication(BasicBlock *BB);
/// Check if this pointer is consecutive when vectorizing. This happens
/// when the last index of the GEP is the induction variable, or that the
/// pointer itself is an induction variable.
/// This check allows us to vectorize A[idx] into a wide load/store.
/// Returns:
/// 0 - Stride is unknown or non-consecutive.
/// 1 - Address is consecutive.
/// -1 - Address is consecutive, and decreasing.
int isConsecutivePtr(Value *Ptr);
/// Returns true if the value V is uniform within the loop.
bool isUniform(Value *V);
/// Returns true if this instruction will remain scalar after vectorization.
bool isUniformAfterVectorization(Instruction* I) { return Uniforms.count(I); }
/// Returns the information that we collected about runtime memory check.
const RuntimePointerChecking *getRuntimePointerChecking() const {
return LAI->getRuntimePointerChecking();
}
const LoopAccessInfo *getLAI() const {
return LAI;
}
/// \brief Check if \p Instr belongs to any interleaved access group.
bool isAccessInterleaved(Instruction *Instr) {
return InterleaveInfo.isInterleaved(Instr);
}
/// \brief Get the interleaved access group that \p Instr belongs to.
const InterleaveGroup *getInterleavedAccessGroup(Instruction *Instr) {
return InterleaveInfo.getInterleaveGroup(Instr);
}
unsigned getMaxSafeDepDistBytes() { return LAI->getMaxSafeDepDistBytes(); }
bool hasStride(Value *V) { return StrideSet.count(V); }
bool mustCheckStrides() { return !StrideSet.empty(); }
SmallPtrSet<Value *, 8>::iterator strides_begin() {
return StrideSet.begin();
}
SmallPtrSet<Value *, 8>::iterator strides_end() { return StrideSet.end(); }
/// Returns true if the target machine supports masked store operation
/// for the given \p DataType and kind of access to \p Ptr.
bool isLegalMaskedStore(Type *DataType, Value *Ptr) {
return TTI->isLegalMaskedStore(DataType, isConsecutivePtr(Ptr));
}
/// Returns true if the target machine supports masked load operation
/// for the given \p DataType and kind of access to \p Ptr.
bool isLegalMaskedLoad(Type *DataType, Value *Ptr) {
return TTI->isLegalMaskedLoad(DataType, isConsecutivePtr(Ptr));
}
/// Returns true if vector representation of the instruction \p I
/// requires mask.
bool isMaskRequired(const Instruction* I) {
return (MaskedOp.count(I) != 0);
}
unsigned getNumStores() const {
return LAI->getNumStores();
}
unsigned getNumLoads() const {
return LAI->getNumLoads();
}
unsigned getNumPredStores() const {
return NumPredStores;
}
private:
/// Check if a single basic block loop is vectorizable.
/// At this point we know that this is a loop with a constant trip count
/// and we only need to check individual instructions.
bool canVectorizeInstrs();
/// When we vectorize loops we may change the order in which
/// we read and write from memory. This method checks if it is
/// legal to vectorize the code, considering only memory constrains.
/// Returns true if the loop is vectorizable
bool canVectorizeMemory();
/// Return true if we can vectorize this loop using the IF-conversion
/// transformation.
bool canVectorizeWithIfConvert();
/// Collect the variables that need to stay uniform after vectorization.
void collectLoopUniforms();
/// Return true if all of the instructions in the block can be speculatively
/// executed. \p SafePtrs is a list of addresses that are known to be legal
/// and we know that we can read from them without segfault.
bool blockCanBePredicated(BasicBlock *BB, SmallPtrSetImpl<Value *> &SafePtrs);
/// Returns the induction kind of Phi and record the step. This function may
/// return NoInduction if the PHI is not an induction variable.
InductionKind isInductionVariable(PHINode *Phi, ConstantInt *&StepValue);
/// \brief Collect memory access with loop invariant strides.
///
/// Looks for accesses like "a[i * StrideA]" where "StrideA" is loop
/// invariant.
void collectStridedAccess(Value *LoadOrStoreInst);
/// Report an analysis message to assist the user in diagnosing loops that are
/// not vectorized. These are handled as LoopAccessReport rather than
/// VectorizationReport because the << operator of VectorizationReport returns
/// LoopAccessReport.
void emitAnalysis(const LoopAccessReport &Message) {
LoopAccessReport::emitAnalysis(Message, TheFunction, TheLoop, LV_NAME);
}
unsigned NumPredStores;
/// The loop that we evaluate.
Loop *TheLoop;
/// Scev analysis.
ScalarEvolution *SE;
/// Target Library Info.
TargetLibraryInfo *TLI;
/// Parent function
Function *TheFunction;
/// Target Transform Info
const TargetTransformInfo *TTI;
/// Dominator Tree.
DominatorTree *DT;
// LoopAccess analysis.
LoopAccessAnalysis *LAA;
// And the loop-accesses info corresponding to this loop. This pointer is
// null until canVectorizeMemory sets it up.
const LoopAccessInfo *LAI;
/// The interleave access information contains groups of interleaved accesses
/// with the same stride and close to each other.
InterleavedAccessInfo InterleaveInfo;
// --- vectorization state --- //
/// Holds the integer induction variable. This is the counter of the
/// loop.
PHINode *Induction;
/// Holds the reduction variables.
ReductionList Reductions;
/// Holds all of the induction variables that we found in the loop.
/// Notice that inductions don't need to start at zero and that induction
/// variables can be pointers.
InductionList Inductions;
/// Holds the widest induction type encountered.
Type *WidestIndTy;
/// Allowed outside users. This holds the reduction
/// vars which can be accessed from outside the loop.
SmallPtrSet<Value*, 4> AllowedExit;
/// This set holds the variables which are known to be uniform after
/// vectorization.
SmallPtrSet<Instruction*, 4> Uniforms;
/// Can we assume the absence of NaNs.
bool HasFunNoNaNAttr;
ValueToValueMap Strides;
SmallPtrSet<Value *, 8> StrideSet;
/// While vectorizing these instructions we have to generate a
/// call to the appropriate masked intrinsic
SmallPtrSet<const Instruction*, 8> MaskedOp;
};
/// LoopVectorizationCostModel - estimates the expected speedups due to
/// vectorization.
/// In many cases vectorization is not profitable. This can happen because of
/// a number of reasons. In this class we mainly attempt to predict the
/// expected speedup/slowdowns due to the supported instruction set. We use the
/// TargetTransformInfo to query the different backends for the cost of
/// different operations.
class LoopVectorizationCostModel {
public:
LoopVectorizationCostModel(Loop *L, ScalarEvolution *SE, LoopInfo *LI,
LoopVectorizationLegality *Legal,
const TargetTransformInfo &TTI,
const TargetLibraryInfo *TLI, AssumptionCache *AC,
const Function *F, const LoopVectorizeHints *Hints)
: TheLoop(L), SE(SE), LI(LI), Legal(Legal), TTI(TTI), TLI(TLI),
TheFunction(F), Hints(Hints) {
CodeMetrics::collectEphemeralValues(L, AC, EphValues);
}
/// Information about vectorization costs
struct VectorizationFactor {
unsigned Width; // Vector width with best cost
unsigned Cost; // Cost of the loop with that width
};
/// \return The most profitable vectorization factor and the cost of that VF.
/// This method checks every power of two up to VF. If UserVF is not ZERO
/// then this vectorization factor will be selected if vectorization is
/// possible.
VectorizationFactor selectVectorizationFactor(bool OptForSize);
/// \return The size (in bits) of the widest type in the code that
/// needs to be vectorized. We ignore values that remain scalar such as
/// 64 bit loop indices.
unsigned getWidestType();
/// \return The desired interleave count.
/// If interleave count has been specified by metadata it will be returned.
/// Otherwise, the interleave count is computed and returned. VF and LoopCost
/// are the selected vectorization factor and the cost of the selected VF.
unsigned selectInterleaveCount(bool OptForSize, unsigned VF,
unsigned LoopCost);
/// \return The most profitable unroll factor.
/// This method finds the best unroll-factor based on register pressure and
/// other parameters. VF and LoopCost are the selected vectorization factor
/// and the cost of the selected VF.
unsigned computeInterleaveCount(bool OptForSize, unsigned VF,
unsigned LoopCost);
/// \brief A struct that represents some properties of the register usage
/// of a loop.
struct RegisterUsage {
/// Holds the number of loop invariant values that are used in the loop.
unsigned LoopInvariantRegs;
/// Holds the maximum number of concurrent live intervals in the loop.
unsigned MaxLocalUsers;
/// Holds the number of instructions in the loop.
unsigned NumInstructions;
};
/// \return information about the register usage of the loop.
RegisterUsage calculateRegisterUsage();
private:
/// Returns the expected execution cost. The unit of the cost does
/// not matter because we use the 'cost' units to compare different
/// vector widths. The cost that is returned is *not* normalized by
/// the factor width.
unsigned expectedCost(unsigned VF);
/// Returns the execution time cost of an instruction for a given vector
/// width. Vector width of one means scalar.
unsigned getInstructionCost(Instruction *I, unsigned VF);
/// Returns whether the instruction is a load or store and will be a emitted
/// as a vector operation.
bool isConsecutiveLoadOrStore(Instruction *I);
/// Report an analysis message to assist the user in diagnosing loops that are
/// not vectorized. These are handled as LoopAccessReport rather than
/// VectorizationReport because the << operator of VectorizationReport returns
/// LoopAccessReport.
void emitAnalysis(const LoopAccessReport &Message) {
LoopAccessReport::emitAnalysis(Message, TheFunction, TheLoop, LV_NAME);
}
/// Values used only by @llvm.assume calls.
SmallPtrSet<const Value *, 32> EphValues;
/// The loop that we evaluate.
Loop *TheLoop;
/// Scev analysis.
ScalarEvolution *SE;
/// Loop Info analysis.
LoopInfo *LI;
/// Vectorization legality.
LoopVectorizationLegality *Legal;
/// Vector target information.
const TargetTransformInfo &TTI;
/// Target Library Info.
const TargetLibraryInfo *TLI;
const Function *TheFunction;
// Loop Vectorize Hint.
const LoopVectorizeHints *Hints;
};
/// Utility class for getting and setting loop vectorizer hints in the form
/// of loop metadata.
/// This class keeps a number of loop annotations locally (as member variables)
/// and can, upon request, write them back as metadata on the loop. It will
/// initially scan the loop for existing metadata, and will update the local
/// values based on information in the loop.
/// We cannot write all values to metadata, as the mere presence of some info,
/// for example 'force', means a decision has been made. So, we need to be
/// careful NOT to add them if the user hasn't specifically asked so.
class LoopVectorizeHints {
enum HintKind {
HK_WIDTH,
HK_UNROLL,
HK_FORCE
};
/// Hint - associates name and validation with the hint value.
struct Hint {
const char * Name;
unsigned Value; // This may have to change for non-numeric values.
HintKind Kind;
Hint(const char * Name, unsigned Value, HintKind Kind)
: Name(Name), Value(Value), Kind(Kind) { }
bool validate(unsigned Val) {
switch (Kind) {
case HK_WIDTH:
return isPowerOf2_32(Val) && Val <= VectorizerParams::MaxVectorWidth;
case HK_UNROLL:
return isPowerOf2_32(Val) && Val <= MaxInterleaveFactor;
case HK_FORCE:
return (Val <= 1);
}
return false;
}
};
/// Vectorization width.
Hint Width;
/// Vectorization interleave factor.
Hint Interleave;
/// Vectorization forced
Hint Force;
/// Return the loop metadata prefix.
static StringRef Prefix() { return "llvm.loop."; }
public:
enum ForceKind {
FK_Undefined = -1, ///< Not selected.
FK_Disabled = 0, ///< Forcing disabled.
FK_Enabled = 1, ///< Forcing enabled.
};
LoopVectorizeHints(const Loop *L, bool DisableInterleaving)
: Width("vectorize.width", VectorizerParams::VectorizationFactor,
HK_WIDTH),
Interleave("interleave.count", DisableInterleaving, HK_UNROLL),
Force("vectorize.enable", FK_Undefined, HK_FORCE),
TheLoop(L) {
// Populate values with existing loop metadata.
getHintsFromMetadata();
// force-vector-interleave overrides DisableInterleaving.
if (VectorizerParams::isInterleaveForced())
Interleave.Value = VectorizerParams::VectorizationInterleave;
DEBUG(if (DisableInterleaving && Interleave.Value == 1) dbgs()
<< "LV: Interleaving disabled by the pass manager\n");
}
/// Mark the loop L as already vectorized by setting the width to 1.
void setAlreadyVectorized() {
Width.Value = Interleave.Value = 1;
Hint Hints[] = {Width, Interleave};
writeHintsToMetadata(Hints);
}
/// Dumps all the hint information.
std::string emitRemark() const {
VectorizationReport R;
if (Force.Value == LoopVectorizeHints::FK_Disabled)
R << "vectorization is explicitly disabled";
else {
R << "use -Rpass-analysis=loop-vectorize for more info";
if (Force.Value == LoopVectorizeHints::FK_Enabled) {
R << " (Force=true";
if (Width.Value != 0)
R << ", Vector Width=" << Width.Value;
if (Interleave.Value != 0)
R << ", Interleave Count=" << Interleave.Value;
R << ")";
}
}
return R.str();
}
unsigned getWidth() const { return Width.Value; }
unsigned getInterleave() const { return Interleave.Value; }
enum ForceKind getForce() const { return (ForceKind)Force.Value; }
private:
/// Find hints specified in the loop metadata and update local values.
void getHintsFromMetadata() {
MDNode *LoopID = TheLoop->getLoopID();
if (!LoopID)
return;
// First operand should refer to the loop id itself.
assert(LoopID->getNumOperands() > 0 && "requires at least one operand");
assert(LoopID->getOperand(0) == LoopID && "invalid loop id");
for (unsigned i = 1, ie = LoopID->getNumOperands(); i < ie; ++i) {
const MDString *S = nullptr;
SmallVector<Metadata *, 4> Args;
// The expected hint is either a MDString or a MDNode with the first
// operand a MDString.
if (const MDNode *MD = dyn_cast<MDNode>(LoopID->getOperand(i))) {
if (!MD || MD->getNumOperands() == 0)
continue;
S = dyn_cast<MDString>(MD->getOperand(0));
for (unsigned i = 1, ie = MD->getNumOperands(); i < ie; ++i)
Args.push_back(MD->getOperand(i));
} else {
S = dyn_cast<MDString>(LoopID->getOperand(i));
assert(Args.size() == 0 && "too many arguments for MDString");
}
if (!S)
continue;
// Check if the hint starts with the loop metadata prefix.
StringRef Name = S->getString();
if (Args.size() == 1)
setHint(Name, Args[0]);
}
}
/// Checks string hint with one operand and set value if valid.
void setHint(StringRef Name, Metadata *Arg) {
if (!Name.startswith(Prefix()))
return;
Name = Name.substr(Prefix().size(), StringRef::npos);
const ConstantInt *C = mdconst::dyn_extract<ConstantInt>(Arg);
if (!C) return;
unsigned Val = C->getZExtValue();
Hint *Hints[] = {&Width, &Interleave, &Force};
for (auto H : Hints) {
if (Name == H->Name) {
if (H->validate(Val))
H->Value = Val;
else
DEBUG(dbgs() << "LV: ignoring invalid hint '" << Name << "'\n");
break;
}
}
}
/// Create a new hint from name / value pair.
MDNode *createHintMetadata(StringRef Name, unsigned V) const {
LLVMContext &Context = TheLoop->getHeader()->getContext();
Metadata *MDs[] = {MDString::get(Context, Name),
ConstantAsMetadata::get(
ConstantInt::get(Type::getInt32Ty(Context), V))};
return MDNode::get(Context, MDs);
}
/// Matches metadata with hint name.
bool matchesHintMetadataName(MDNode *Node, ArrayRef<Hint> HintTypes) {
MDString* Name = dyn_cast<MDString>(Node->getOperand(0));
if (!Name)
return false;
for (auto H : HintTypes)
if (Name->getString().endswith(H.Name))
return true;
return false;
}
/// Sets current hints into loop metadata, keeping other values intact.
void writeHintsToMetadata(ArrayRef<Hint> HintTypes) {
if (HintTypes.size() == 0)
return;
// Reserve the first element to LoopID (see below).
SmallVector<Metadata *, 4> MDs(1);
// If the loop already has metadata, then ignore the existing operands.
MDNode *LoopID = TheLoop->getLoopID();
if (LoopID) {
for (unsigned i = 1, ie = LoopID->getNumOperands(); i < ie; ++i) {
MDNode *Node = cast<MDNode>(LoopID->getOperand(i));
// If node in update list, ignore old value.
if (!matchesHintMetadataName(Node, HintTypes))
MDs.push_back(Node);
}
}
// Now, add the missing hints.
for (auto H : HintTypes)
MDs.push_back(createHintMetadata(Twine(Prefix(), H.Name).str(), H.Value));
// Replace current metadata node with new one.
LLVMContext &Context = TheLoop->getHeader()->getContext();
MDNode *NewLoopID = MDNode::get(Context, MDs);
// Set operand 0 to refer to the loop id itself.
NewLoopID->replaceOperandWith(0, NewLoopID);
TheLoop->setLoopID(NewLoopID);
}
/// The loop these hints belong to.
const Loop *TheLoop;
};
static void emitMissedWarning(Function *F, Loop *L,
const LoopVectorizeHints &LH) {
emitOptimizationRemarkMissed(F->getContext(), DEBUG_TYPE, *F,
L->getStartLoc(), LH.emitRemark());
if (LH.getForce() == LoopVectorizeHints::FK_Enabled) {
if (LH.getWidth() != 1)
emitLoopVectorizeWarning(
F->getContext(), *F, L->getStartLoc(),
"failed explicitly specified loop vectorization");
else if (LH.getInterleave() != 1)
emitLoopInterleaveWarning(
F->getContext(), *F, L->getStartLoc(),
"failed explicitly specified loop interleaving");
}
}
static void addInnerLoop(Loop &L, SmallVectorImpl<Loop *> &V) {
if (L.empty())
return V.push_back(&L);
for (Loop *InnerL : L)
addInnerLoop(*InnerL, V);
}
/// The LoopVectorize Pass.
struct LoopVectorize : public FunctionPass {
/// Pass identification, replacement for typeid
static char ID;
explicit LoopVectorize(bool NoUnrolling = false, bool AlwaysVectorize = true)
: FunctionPass(ID),
DisableUnrolling(NoUnrolling),
AlwaysVectorize(AlwaysVectorize) {
initializeLoopVectorizePass(*PassRegistry::getPassRegistry());
}
ScalarEvolution *SE;
LoopInfo *LI;
TargetTransformInfo *TTI;
DominatorTree *DT;
BlockFrequencyInfo *BFI;
TargetLibraryInfo *TLI;
AliasAnalysis *AA;
AssumptionCache *AC;
LoopAccessAnalysis *LAA;
bool DisableUnrolling;
bool AlwaysVectorize;
BlockFrequency ColdEntryFreq;
bool runOnFunction(Function &F) override {
SE = &getAnalysis<ScalarEvolution>();
LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
TTI = &getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
BFI = &getAnalysis<BlockFrequencyInfo>();
auto *TLIP = getAnalysisIfAvailable<TargetLibraryInfoWrapperPass>();
TLI = TLIP ? &TLIP->getTLI() : nullptr;
AA = &getAnalysis<AliasAnalysis>();
AC = &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
LAA = &getAnalysis<LoopAccessAnalysis>();
// Compute some weights outside of the loop over the loops. Compute this
// using a BranchProbability to re-use its scaling math.
const BranchProbability ColdProb(1, 5); // 20%
ColdEntryFreq = BlockFrequency(BFI->getEntryFreq()) * ColdProb;
// Don't attempt if
// 1. the target claims to have no vector registers, and
// 2. interleaving won't help ILP.
//
// The second condition is necessary because, even if the target has no
// vector registers, loop vectorization may still enable scalar
// interleaving.
if (!TTI->getNumberOfRegisters(true) && TTI->getMaxInterleaveFactor(1) < 2)
return false;
// Build up a worklist of inner-loops to vectorize. This is necessary as
// the act of vectorizing or partially unrolling a loop creates new loops
// and can invalidate iterators across the loops.
SmallVector<Loop *, 8> Worklist;
for (Loop *L : *LI)
addInnerLoop(*L, Worklist);
LoopsAnalyzed += Worklist.size();
// Now walk the identified inner loops.
bool Changed = false;
while (!Worklist.empty())
Changed |= processLoop(Worklist.pop_back_val());
// Process each loop nest in the function.
return Changed;
}
static void AddRuntimeUnrollDisableMetaData(Loop *L) {
SmallVector<Metadata *, 4> MDs;
// Reserve first location for self reference to the LoopID metadata node.
MDs.push_back(nullptr);
bool IsUnrollMetadata = false;
MDNode *LoopID = L->getLoopID();
if (LoopID) {
// First find existing loop unrolling disable metadata.
for (unsigned i = 1, ie = LoopID->getNumOperands(); i < ie; ++i) {
MDNode *MD = dyn_cast<MDNode>(LoopID->getOperand(i));
if (MD) {
const MDString *S = dyn_cast<MDString>(MD->getOperand(0));
IsUnrollMetadata =
S && S->getString().startswith("llvm.loop.unroll.disable");
}
MDs.push_back(LoopID->getOperand(i));
}
}
if (!IsUnrollMetadata) {
// Add runtime unroll disable metadata.
LLVMContext &Context = L->getHeader()->getContext();
SmallVector<Metadata *, 1> DisableOperands;
DisableOperands.push_back(
MDString::get(Context, "llvm.loop.unroll.runtime.disable"));
MDNode *DisableNode = MDNode::get(Context, DisableOperands);
MDs.push_back(DisableNode);
MDNode *NewLoopID = MDNode::get(Context, MDs);
// Set operand 0 to refer to the loop id itself.
NewLoopID->replaceOperandWith(0, NewLoopID);
L->setLoopID(NewLoopID);
}
}
bool processLoop(Loop *L) {
assert(L->empty() && "Only process inner loops.");
#ifndef NDEBUG
const std::string DebugLocStr = getDebugLocString(L);
#endif /* NDEBUG */
DEBUG(dbgs() << "\nLV: Checking a loop in \""
<< L->getHeader()->getParent()->getName() << "\" from "
<< DebugLocStr << "\n");
LoopVectorizeHints Hints(L, DisableUnrolling);
DEBUG(dbgs() << "LV: Loop hints:"
<< " force="
<< (Hints.getForce() == LoopVectorizeHints::FK_Disabled
? "disabled"
: (Hints.getForce() == LoopVectorizeHints::FK_Enabled
? "enabled"
: "?")) << " width=" << Hints.getWidth()
<< " unroll=" << Hints.getInterleave() << "\n");
// Function containing loop
Function *F = L->getHeader()->getParent();
// Looking at the diagnostic output is the only way to determine if a loop
// was vectorized (other than looking at the IR or machine code), so it
// is important to generate an optimization remark for each loop. Most of
// these messages are generated by emitOptimizationRemarkAnalysis. Remarks
// generated by emitOptimizationRemark and emitOptimizationRemarkMissed are
// less verbose reporting vectorized loops and unvectorized loops that may
// benefit from vectorization, respectively.
if (Hints.getForce() == LoopVectorizeHints::FK_Disabled) {
DEBUG(dbgs() << "LV: Not vectorizing: #pragma vectorize disable.\n");
emitOptimizationRemarkAnalysis(F->getContext(), DEBUG_TYPE, *F,
L->getStartLoc(), Hints.emitRemark());
return false;
}
if (!AlwaysVectorize && Hints.getForce() != LoopVectorizeHints::FK_Enabled) {
DEBUG(dbgs() << "LV: Not vectorizing: No #pragma vectorize enable.\n");
emitOptimizationRemarkAnalysis(F->getContext(), DEBUG_TYPE, *F,
L->getStartLoc(), Hints.emitRemark());
return false;
}
if (Hints.getWidth() == 1 && Hints.getInterleave() == 1) {
DEBUG(dbgs() << "LV: Not vectorizing: Disabled/already vectorized.\n");
emitOptimizationRemarkAnalysis(
F->getContext(), DEBUG_TYPE, *F, L->getStartLoc(),
"loop not vectorized: vector width and interleave count are "
"explicitly set to 1");
return false;
}
// Check the loop for a trip count threshold:
// do not vectorize loops with a tiny trip count.
const unsigned TC = SE->getSmallConstantTripCount(L);
if (TC > 0u && TC < TinyTripCountVectorThreshold) {
DEBUG(dbgs() << "LV: Found a loop with a very small trip count. "
<< "This loop is not worth vectorizing.");
if (Hints.getForce() == LoopVectorizeHints::FK_Enabled)
DEBUG(dbgs() << " But vectorizing was explicitly forced.\n");
else {
DEBUG(dbgs() << "\n");
emitOptimizationRemarkAnalysis(
F->getContext(), DEBUG_TYPE, *F, L->getStartLoc(),
"vectorization is not beneficial and is not explicitly forced");
return false;
}
}
// Check if it is legal to vectorize the loop.
LoopVectorizationLegality LVL(L, SE, DT, TLI, AA, F, TTI, LAA);
if (!LVL.canVectorize()) {
DEBUG(dbgs() << "LV: Not vectorizing: Cannot prove legality.\n");
emitMissedWarning(F, L, Hints);
return false;
}
// Use the cost model.
LoopVectorizationCostModel CM(L, SE, LI, &LVL, *TTI, TLI, AC, F, &Hints);
// Check the function attributes to find out if this function should be
// optimized for size.
bool OptForSize = Hints.getForce() != LoopVectorizeHints::FK_Enabled &&
F->hasFnAttribute(Attribute::OptimizeForSize);
// Compute the weighted frequency of this loop being executed and see if it
// is less than 20% of the function entry baseline frequency. Note that we
// always have a canonical loop here because we think we *can* vectoriez.
// FIXME: This is hidden behind a flag due to pervasive problems with
// exactly what block frequency models.
if (LoopVectorizeWithBlockFrequency) {
BlockFrequency LoopEntryFreq = BFI->getBlockFreq(L->getLoopPreheader());
if (Hints.getForce() != LoopVectorizeHints::FK_Enabled &&
LoopEntryFreq < ColdEntryFreq)
OptForSize = true;
}
// Check the function attributes to see if implicit floats are allowed.a
// FIXME: This check doesn't seem possibly correct -- what if the loop is
// an integer loop and the vector instructions selected are purely integer
// vector instructions?
if (F->hasFnAttribute(Attribute::NoImplicitFloat)) {
DEBUG(dbgs() << "LV: Can't vectorize when the NoImplicitFloat"
"attribute is used.\n");
emitOptimizationRemarkAnalysis(
F->getContext(), DEBUG_TYPE, *F, L->getStartLoc(),
"loop not vectorized due to NoImplicitFloat attribute");
emitMissedWarning(F, L, Hints);
return false;
}
// Select the optimal vectorization factor.
const LoopVectorizationCostModel::VectorizationFactor VF =
CM.selectVectorizationFactor(OptForSize);
// Select the interleave count.
unsigned IC = CM.selectInterleaveCount(OptForSize, VF.Width, VF.Cost);
DEBUG(dbgs() << "LV: Found a vectorizable loop (" << VF.Width << ") in "
<< DebugLocStr << '\n');
DEBUG(dbgs() << "LV: Interleave Count is " << IC << '\n');
if (VF.Width == 1) {
DEBUG(dbgs() << "LV: Vectorization is possible but not beneficial\n");
if (IC == 1) {
emitOptimizationRemarkAnalysis(
F->getContext(), DEBUG_TYPE, *F, L->getStartLoc(),
"not beneficial to vectorize and user disabled interleaving");
return false;
}
DEBUG(dbgs() << "LV: Trying to at least unroll the loops.\n");
// Report the unrolling decision.
emitOptimizationRemark(F->getContext(), DEBUG_TYPE, *F, L->getStartLoc(),
Twine("interleaved by " + Twine(IC) +
" (vectorization not beneficial)"));
InnerLoopUnroller Unroller(L, SE, LI, DT, TLI, TTI, IC);
Unroller.vectorize(&LVL);
} else {
// If we decided that it is *legal* to vectorize the loop then do it.
InnerLoopVectorizer LB(L, SE, LI, DT, TLI, TTI, VF.Width, IC);
LB.vectorize(&LVL);
++LoopsVectorized;
// Add metadata to disable runtime unrolling scalar loop when there's no
// runtime check about strides and memory. Because at this situation,
// scalar loop is rarely used not worthy to be unrolled.
if (!LB.IsSafetyChecksAdded())
AddRuntimeUnrollDisableMetaData(L);
// Report the vectorization decision.
emitOptimizationRemark(F->getContext(), DEBUG_TYPE, *F, L->getStartLoc(),
Twine("vectorized loop (vectorization width: ") +
Twine(VF.Width) + ", interleaved count: " +
Twine(IC) + ")");
}
// Mark the loop as already vectorized to avoid vectorizing again.
Hints.setAlreadyVectorized();
DEBUG(verifyFunction(*L->getHeader()->getParent()));
return true;
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addRequired<AssumptionCacheTracker>();
AU.addRequiredID(LoopSimplifyID);
AU.addRequiredID(LCSSAID);
AU.addRequired<BlockFrequencyInfo>();
AU.addRequired<DominatorTreeWrapperPass>();
AU.addRequired<LoopInfoWrapperPass>();
AU.addRequired<ScalarEvolution>();
AU.addRequired<TargetTransformInfoWrapperPass>();
AU.addRequired<AliasAnalysis>();
AU.addRequired<LoopAccessAnalysis>();
AU.addPreserved<LoopInfoWrapperPass>();
AU.addPreserved<DominatorTreeWrapperPass>();
AU.addPreserved<AliasAnalysis>();
}
};
} // end anonymous namespace
//===----------------------------------------------------------------------===//
// Implementation of LoopVectorizationLegality, InnerLoopVectorizer and
// LoopVectorizationCostModel.
//===----------------------------------------------------------------------===//
Value *InnerLoopVectorizer::getBroadcastInstrs(Value *V) {
// We need to place the broadcast of invariant variables outside the loop.
Instruction *Instr = dyn_cast<Instruction>(V);
bool NewInstr =
(Instr && std::find(LoopVectorBody.begin(), LoopVectorBody.end(),
Instr->getParent()) != LoopVectorBody.end());
bool Invariant = OrigLoop->isLoopInvariant(V) && !NewInstr;
// Place the code for broadcasting invariant variables in the new preheader.
IRBuilder<>::InsertPointGuard Guard(Builder);
if (Invariant)
Builder.SetInsertPoint(LoopVectorPreHeader->getTerminator());
// Broadcast the scalar into all locations in the vector.
Value *Shuf = Builder.CreateVectorSplat(VF, V, "broadcast");
return Shuf;
}
Value *InnerLoopVectorizer::getStepVector(Value *Val, int StartIdx,
Value *Step) {
assert(Val->getType()->isVectorTy() && "Must be a vector");
assert(Val->getType()->getScalarType()->isIntegerTy() &&
"Elem must be an integer");
assert(Step->getType() == Val->getType()->getScalarType() &&
"Step has wrong type");
// Create the types.
Type *ITy = Val->getType()->getScalarType();
VectorType *Ty = cast<VectorType>(Val->getType());
int VLen = Ty->getNumElements();
SmallVector<Constant*, 8> Indices;
// Create a vector of consecutive numbers from zero to VF.
for (int i = 0; i < VLen; ++i)
Indices.push_back(ConstantInt::get(ITy, StartIdx + i));
// Add the consecutive indices to the vector value.
Constant *Cv = ConstantVector::get(Indices);
assert(Cv->getType() == Val->getType() && "Invalid consecutive vec");
Step = Builder.CreateVectorSplat(VLen, Step);
assert(Step->getType() == Val->getType() && "Invalid step vec");
// FIXME: The newly created binary instructions should contain nsw/nuw flags,
// which can be found from the original scalar operations.
Step = Builder.CreateMul(Cv, Step);
return Builder.CreateAdd(Val, Step, "induction");
}
int LoopVectorizationLegality::isConsecutivePtr(Value *Ptr) {
assert(Ptr->getType()->isPointerTy() && "Unexpected non-ptr");
// Make sure that the pointer does not point to structs.
if (Ptr->getType()->getPointerElementType()->isAggregateType())
return 0;
// If this value is a pointer induction variable we know it is consecutive.
PHINode *Phi = dyn_cast_or_null<PHINode>(Ptr);
if (Phi && Inductions.count(Phi)) {
InductionInfo II = Inductions[Phi];
return II.getConsecutiveDirection();
}
GetElementPtrInst *Gep = dyn_cast_or_null<GetElementPtrInst>(Ptr);
if (!Gep)
return 0;
unsigned NumOperands = Gep->getNumOperands();
Value *GpPtr = Gep->getPointerOperand();
// If this GEP value is a consecutive pointer induction variable and all of
// the indices are constant then we know it is consecutive. We can
Phi = dyn_cast<PHINode>(GpPtr);
if (Phi && Inductions.count(Phi)) {
// Make sure that the pointer does not point to structs.
PointerType *GepPtrType = cast<PointerType>(GpPtr->getType());
if (GepPtrType->getElementType()->isAggregateType())
return 0;
// Make sure that all of the index operands are loop invariant.
for (unsigned i = 1; i < NumOperands; ++i)
if (!SE->isLoopInvariant(SE->getSCEV(Gep->getOperand(i)), TheLoop))
return 0;
InductionInfo II = Inductions[Phi];
return II.getConsecutiveDirection();
}
unsigned InductionOperand = getGEPInductionOperand(Gep);
// Check that all of the gep indices are uniform except for our induction
// operand.
for (unsigned i = 0; i != NumOperands; ++i)
if (i != InductionOperand &&
!SE->isLoopInvariant(SE->getSCEV(Gep->getOperand(i)), TheLoop))
return 0;
// We can emit wide load/stores only if the last non-zero index is the
// induction variable.
const SCEV *Last = nullptr;
if (!Strides.count(Gep))
Last = SE->getSCEV(Gep->getOperand(InductionOperand));
else {
// Because of the multiplication by a stride we can have a s/zext cast.
// We are going to replace this stride by 1 so the cast is safe to ignore.
//
// %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
// %0 = trunc i64 %indvars.iv to i32
// %mul = mul i32 %0, %Stride1
// %idxprom = zext i32 %mul to i64 << Safe cast.
// %arrayidx = getelementptr inbounds i32* %B, i64 %idxprom
//
Last = replaceSymbolicStrideSCEV(SE, Strides,
Gep->getOperand(InductionOperand), Gep);
if (const SCEVCastExpr *C = dyn_cast<SCEVCastExpr>(Last))
Last =
(C->getSCEVType() == scSignExtend || C->getSCEVType() == scZeroExtend)
? C->getOperand()
: Last;
}
if (const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(Last)) {
const SCEV *Step = AR->getStepRecurrence(*SE);
// The memory is consecutive because the last index is consecutive
// and all other indices are loop invariant.
if (Step->isOne())
return 1;
if (Step->isAllOnesValue())
return -1;
}
return 0;
}
bool LoopVectorizationLegality::isUniform(Value *V) {
return LAI->isUniform(V);
}
InnerLoopVectorizer::VectorParts&
InnerLoopVectorizer::getVectorValue(Value *V) {
assert(V != Induction && "The new induction variable should not be used.");
assert(!V->getType()->isVectorTy() && "Can't widen a vector");
// If we have a stride that is replaced by one, do it here.
if (Legal->hasStride(V))
V = ConstantInt::get(V->getType(), 1);
// If we have this scalar in the map, return it.
if (WidenMap.has(V))
return WidenMap.get(V);
// If this scalar is unknown, assume that it is a constant or that it is
// loop invariant. Broadcast V and save the value for future uses.
Value *B = getBroadcastInstrs(V);
return WidenMap.splat(V, B);
}
Value *InnerLoopVectorizer::reverseVector(Value *Vec) {
assert(Vec->getType()->isVectorTy() && "Invalid type");
SmallVector<Constant*, 8> ShuffleMask;
for (unsigned i = 0; i < VF; ++i)
ShuffleMask.push_back(Builder.getInt32(VF - i - 1));
return Builder.CreateShuffleVector(Vec, UndefValue::get(Vec->getType()),
ConstantVector::get(ShuffleMask),
"reverse");
}
// Get a mask to interleave \p NumVec vectors into a wide vector.
// I.e. <0, VF, VF*2, ..., VF*(NumVec-1), 1, VF+1, VF*2+1, ...>
// E.g. For 2 interleaved vectors, if VF is 4, the mask is:
// <0, 4, 1, 5, 2, 6, 3, 7>
static Constant *getInterleavedMask(IRBuilder<> &Builder, unsigned VF,
unsigned NumVec) {
SmallVector<Constant *, 16> Mask;
for (unsigned i = 0; i < VF; i++)
for (unsigned j = 0; j < NumVec; j++)
Mask.push_back(Builder.getInt32(j * VF + i));
return ConstantVector::get(Mask);
}
// Get the strided mask starting from index \p Start.
// I.e. <Start, Start + Stride, ..., Start + Stride*(VF-1)>
static Constant *getStridedMask(IRBuilder<> &Builder, unsigned Start,
unsigned Stride, unsigned VF) {
SmallVector<Constant *, 16> Mask;
for (unsigned i = 0; i < VF; i++)
Mask.push_back(Builder.getInt32(Start + i * Stride));
return ConstantVector::get(Mask);
}
// Get a mask of two parts: The first part consists of sequential integers
// starting from 0, The second part consists of UNDEFs.
// I.e. <0, 1, 2, ..., NumInt - 1, undef, ..., undef>
static Constant *getSequentialMask(IRBuilder<> &Builder, unsigned NumInt,
unsigned NumUndef) {
SmallVector<Constant *, 16> Mask;
for (unsigned i = 0; i < NumInt; i++)
Mask.push_back(Builder.getInt32(i));
Constant *Undef = UndefValue::get(Builder.getInt32Ty());
for (unsigned i = 0; i < NumUndef; i++)
Mask.push_back(Undef);
return ConstantVector::get(Mask);
}
// Concatenate two vectors with the same element type. The 2nd vector should
// not have more elements than the 1st vector. If the 2nd vector has less
// elements, extend it with UNDEFs.
static Value *ConcatenateTwoVectors(IRBuilder<> &Builder, Value *V1,
Value *V2) {
VectorType *VecTy1 = dyn_cast<VectorType>(V1->getType());
VectorType *VecTy2 = dyn_cast<VectorType>(V2->getType());
assert(VecTy1 && VecTy2 &&
VecTy1->getScalarType() == VecTy2->getScalarType() &&
"Expect two vectors with the same element type");
unsigned NumElts1 = VecTy1->getNumElements();
unsigned NumElts2 = VecTy2->getNumElements();
assert(NumElts1 >= NumElts2 && "Unexpect the first vector has less elements");
if (NumElts1 > NumElts2) {
// Extend with UNDEFs.
Constant *ExtMask =
getSequentialMask(Builder, NumElts2, NumElts1 - NumElts2);
V2 = Builder.CreateShuffleVector(V2, UndefValue::get(VecTy2), ExtMask);
}
Constant *Mask = getSequentialMask(Builder, NumElts1 + NumElts2, 0);
return Builder.CreateShuffleVector(V1, V2, Mask);
}
// Concatenate vectors in the given list. All vectors have the same type.
static Value *ConcatenateVectors(IRBuilder<> &Builder,
ArrayRef<Value *> InputList) {
unsigned NumVec = InputList.size();
assert(NumVec > 1 && "Should be at least two vectors");
SmallVector<Value *, 8> ResList;
ResList.append(InputList.begin(), InputList.end());
do {
SmallVector<Value *, 8> TmpList;
for (unsigned i = 0; i < NumVec - 1; i += 2) {
Value *V0 = ResList[i], *V1 = ResList[i + 1];
assert((V0->getType() == V1->getType() || i == NumVec - 2) &&
"Only the last vector may have a different type");
TmpList.push_back(ConcatenateTwoVectors(Builder, V0, V1));
}
// Push the last vector if the total number of vectors is odd.
if (NumVec % 2 != 0)
TmpList.push_back(ResList[NumVec - 1]);
ResList = TmpList;
NumVec = ResList.size();
} while (NumVec > 1);
return ResList[0];
}
// Try to vectorize the interleave group that \p Instr belongs to.
//
// E.g. Translate following interleaved load group (factor = 3):
// for (i = 0; i < N; i+=3) {
// R = Pic[i]; // Member of index 0
// G = Pic[i+1]; // Member of index 1
// B = Pic[i+2]; // Member of index 2
// ... // do something to R, G, B
// }
// To:
// %wide.vec = load <12 x i32> ; Read 4 tuples of R,G,B
// %R.vec = shuffle %wide.vec, undef, <0, 3, 6, 9> ; R elements
// %G.vec = shuffle %wide.vec, undef, <1, 4, 7, 10> ; G elements
// %B.vec = shuffle %wide.vec, undef, <2, 5, 8, 11> ; B elements
//
// Or translate following interleaved store group (factor = 3):
// for (i = 0; i < N; i+=3) {
// ... do something to R, G, B
// Pic[i] = R; // Member of index 0
// Pic[i+1] = G; // Member of index 1
// Pic[i+2] = B; // Member of index 2
// }
// To:
// %R_G.vec = shuffle %R.vec, %G.vec, <0, 1, 2, ..., 7>
// %B_U.vec = shuffle %B.vec, undef, <0, 1, 2, 3, u, u, u, u>
// %interleaved.vec = shuffle %R_G.vec, %B_U.vec,
// <0, 4, 8, 1, 5, 9, 2, 6, 10, 3, 7, 11> ; Interleave R,G,B elements
// store <12 x i32> %interleaved.vec ; Write 4 tuples of R,G,B
void InnerLoopVectorizer::vectorizeInterleaveGroup(Instruction *Instr) {
const InterleaveGroup *Group = Legal->getInterleavedAccessGroup(Instr);
assert(Group && "Fail to get an interleaved access group.");
// Skip if current instruction is not the insert position.
if (Instr != Group->getInsertPos())
return;
LoadInst *LI = dyn_cast<LoadInst>(Instr);
StoreInst *SI = dyn_cast<StoreInst>(Instr);
Value *Ptr = LI ? LI->getPointerOperand() : SI->getPointerOperand();
// Prepare for the vector type of the interleaved load/store.
Type *ScalarTy = LI ? LI->getType() : SI->getValueOperand()->getType();
unsigned InterleaveFactor = Group->getFactor();
Type *VecTy = VectorType::get(ScalarTy, InterleaveFactor * VF);
Type *PtrTy = VecTy->getPointerTo(Ptr->getType()->getPointerAddressSpace());
// Prepare for the new pointers.
setDebugLocFromInst(Builder, Ptr);
VectorParts &PtrParts = getVectorValue(Ptr);
SmallVector<Value *, 2> NewPtrs;
unsigned Index = Group->getIndex(Instr);
for (unsigned Part = 0; Part < UF; Part++) {
// Extract the pointer for current instruction from the pointer vector. A
// reverse access uses the pointer in the last lane.
Value *NewPtr = Builder.CreateExtractElement(
PtrParts[Part],
Group->isReverse() ? Builder.getInt32(VF - 1) : Builder.getInt32(0));
// Notice current instruction could be any index. Need to adjust the address
// to the member of index 0.
//
// E.g. a = A[i+1]; // Member of index 1 (Current instruction)
// b = A[i]; // Member of index 0
// Current pointer is pointed to A[i+1], adjust it to A[i].
//
// E.g. A[i+1] = a; // Member of index 1
// A[i] = b; // Member of index 0
// A[i+2] = c; // Member of index 2 (Current instruction)
// Current pointer is pointed to A[i+2], adjust it to A[i].
NewPtr = Builder.CreateGEP(NewPtr, Builder.getInt32(-Index));
// Cast to the vector pointer type.
NewPtrs.push_back(Builder.CreateBitCast(NewPtr, PtrTy));
}
setDebugLocFromInst(Builder, Instr);
Value *UndefVec = UndefValue::get(VecTy);
// Vectorize the interleaved load group.
if (LI) {
for (unsigned Part = 0; Part < UF; Part++) {
Instruction *NewLoadInstr = Builder.CreateAlignedLoad(
NewPtrs[Part], Group->getAlignment(), "wide.vec");
for (unsigned i = 0; i < InterleaveFactor; i++) {
Instruction *Member = Group->getMember(i);
// Skip the gaps in the group.
if (!Member)
continue;
Constant *StrideMask = getStridedMask(Builder, i, InterleaveFactor, VF);
Value *StridedVec = Builder.CreateShuffleVector(
NewLoadInstr, UndefVec, StrideMask, "strided.vec");
// If this member has different type, cast the result type.
if (Member->getType() != ScalarTy) {
VectorType *OtherVTy = VectorType::get(Member->getType(), VF);
StridedVec = Builder.CreateBitOrPointerCast(StridedVec, OtherVTy);
}
VectorParts &Entry = WidenMap.get(Member);
Entry[Part] =
Group->isReverse() ? reverseVector(StridedVec) : StridedVec;
}
propagateMetadata(NewLoadInstr, Instr);
}
return;
}
// The sub vector type for current instruction.
VectorType *SubVT = VectorType::get(ScalarTy, VF);
// Vectorize the interleaved store group.
for (unsigned Part = 0; Part < UF; Part++) {
// Collect the stored vector from each member.
SmallVector<Value *, 4> StoredVecs;
for (unsigned i = 0; i < InterleaveFactor; i++) {
// Interleaved store group doesn't allow a gap, so each index has a member
Instruction *Member = Group->getMember(i);
assert(Member && "Fail to get a member from an interleaved store group");
Value *StoredVec =
getVectorValue(dyn_cast<StoreInst>(Member)->getValueOperand())[Part];
if (Group->isReverse())
StoredVec = reverseVector(StoredVec);
// If this member has different type, cast it to an unified type.
if (StoredVec->getType() != SubVT)
StoredVec = Builder.CreateBitOrPointerCast(StoredVec, SubVT);
StoredVecs.push_back(StoredVec);
}
// Concatenate all vectors into a wide vector.
Value *WideVec = ConcatenateVectors(Builder, StoredVecs);
// Interleave the elements in the wide vector.
Constant *IMask = getInterleavedMask(Builder, VF, InterleaveFactor);
Value *IVec = Builder.CreateShuffleVector(WideVec, UndefVec, IMask,
"interleaved.vec");
Instruction *NewStoreInstr =
Builder.CreateAlignedStore(IVec, NewPtrs[Part], Group->getAlignment());
propagateMetadata(NewStoreInstr, Instr);
}
}
void InnerLoopVectorizer::vectorizeMemoryInstruction(Instruction *Instr) {
// Attempt to issue a wide load.
LoadInst *LI = dyn_cast<LoadInst>(Instr);
StoreInst *SI = dyn_cast<StoreInst>(Instr);
assert((LI || SI) && "Invalid Load/Store instruction");
// Try to vectorize the interleave group if this access is interleaved.
if (Legal->isAccessInterleaved(Instr))
return vectorizeInterleaveGroup(Instr);
Type *ScalarDataTy = LI ? LI->getType() : SI->getValueOperand()->getType();
Type *DataTy = VectorType::get(ScalarDataTy, VF);
Value *Ptr = LI ? LI->getPointerOperand() : SI->getPointerOperand();
unsigned Alignment = LI ? LI->getAlignment() : SI->getAlignment();
// An alignment of 0 means target abi alignment. We need to use the scalar's
// target abi alignment in such a case.
const DataLayout &DL = Instr->getModule()->getDataLayout();
if (!Alignment)
Alignment = DL.getABITypeAlignment(ScalarDataTy);
unsigned AddressSpace = Ptr->getType()->getPointerAddressSpace();
unsigned ScalarAllocatedSize = DL.getTypeAllocSize(ScalarDataTy);
unsigned VectorElementSize = DL.getTypeStoreSize(DataTy) / VF;
if (SI && Legal->blockNeedsPredication(SI->getParent()) &&
!Legal->isMaskRequired(SI))
return scalarizeInstruction(Instr, true);
if (ScalarAllocatedSize != VectorElementSize)
return scalarizeInstruction(Instr);
// If the pointer is loop invariant or if it is non-consecutive,
// scalarize the load.
int ConsecutiveStride = Legal->isConsecutivePtr(Ptr);
bool Reverse = ConsecutiveStride < 0;
bool UniformLoad = LI && Legal->isUniform(Ptr);
if (!ConsecutiveStride || UniformLoad)
return scalarizeInstruction(Instr);
Constant *Zero = Builder.getInt32(0);
VectorParts &Entry = WidenMap.get(Instr);
// Handle consecutive loads/stores.
GetElementPtrInst *Gep = dyn_cast<GetElementPtrInst>(Ptr);
if (Gep && Legal->isInductionVariable(Gep->getPointerOperand())) {
setDebugLocFromInst(Builder, Gep);
Value *PtrOperand = Gep->getPointerOperand();
Value *FirstBasePtr = getVectorValue(PtrOperand)[0];
FirstBasePtr = Builder.CreateExtractElement(FirstBasePtr, Zero);
// Create the new GEP with the new induction variable.
GetElementPtrInst *Gep2 = cast<GetElementPtrInst>(Gep->clone());
Gep2->setOperand(0, FirstBasePtr);
Gep2->setName("gep.indvar.base");
Ptr = Builder.Insert(Gep2);
} else if (Gep) {
setDebugLocFromInst(Builder, Gep);
assert(SE->isLoopInvariant(SE->getSCEV(Gep->getPointerOperand()),
OrigLoop) && "Base ptr must be invariant");
// The last index does not have to be the induction. It can be
// consecutive and be a function of the index. For example A[I+1];
unsigned NumOperands = Gep->getNumOperands();
unsigned InductionOperand = getGEPInductionOperand(Gep);
// Create the new GEP with the new induction variable.
GetElementPtrInst *Gep2 = cast<GetElementPtrInst>(Gep->clone());
for (unsigned i = 0; i < NumOperands; ++i) {
Value *GepOperand = Gep->getOperand(i);
Instruction *GepOperandInst = dyn_cast<Instruction>(GepOperand);
// Update last index or loop invariant instruction anchored in loop.
if (i == InductionOperand ||
(GepOperandInst && OrigLoop->contains(GepOperandInst))) {
assert((i == InductionOperand ||
SE->isLoopInvariant(SE->getSCEV(GepOperandInst), OrigLoop)) &&
"Must be last index or loop invariant");
VectorParts &GEPParts = getVectorValue(GepOperand);
Value *Index = GEPParts[0];
Index = Builder.CreateExtractElement(Index, Zero);
Gep2->setOperand(i, Index);
Gep2->setName("gep.indvar.idx");
}
}
Ptr = Builder.Insert(Gep2);
} else {
// Use the induction element ptr.
assert(isa<PHINode>(Ptr) && "Invalid induction ptr");
setDebugLocFromInst(Builder, Ptr);
VectorParts &PtrVal = getVectorValue(Ptr);
Ptr = Builder.CreateExtractElement(PtrVal[0], Zero);
}
VectorParts Mask = createBlockInMask(Instr->getParent());
// Handle Stores:
if (SI) {
assert(!Legal->isUniform(SI->getPointerOperand()) &&
"We do not allow storing to uniform addresses");
setDebugLocFromInst(Builder, SI);
// We don't want to update the value in the map as it might be used in
// another expression. So don't use a reference type for "StoredVal".
VectorParts StoredVal = getVectorValue(SI->getValueOperand());
for (unsigned Part = 0; Part < UF; ++Part) {
// Calculate the pointer for the specific unroll-part.
Value *PartPtr =
Builder.CreateGEP(nullptr, Ptr, Builder.getInt32(Part * VF));
if (Reverse) {
// If we store to reverse consecutive memory locations then we need
// to reverse the order of elements in the stored value.
StoredVal[Part] = reverseVector(StoredVal[Part]);
// If the address is consecutive but reversed, then the
// wide store needs to start at the last vector element.
PartPtr = Builder.CreateGEP(nullptr, Ptr, Builder.getInt32(-Part * VF));
PartPtr = Builder.CreateGEP(nullptr, PartPtr, Builder.getInt32(1 - VF));
Mask[Part] = reverseVector(Mask[Part]);
}
Value *VecPtr = Builder.CreateBitCast(PartPtr,
DataTy->getPointerTo(AddressSpace));
Instruction *NewSI;
if (Legal->isMaskRequired(SI))
NewSI = Builder.CreateMaskedStore(StoredVal[Part], VecPtr, Alignment,
Mask[Part]);
else
NewSI = Builder.CreateAlignedStore(StoredVal[Part], VecPtr, Alignment);
propagateMetadata(NewSI, SI);
}
return;
}
// Handle loads.
assert(LI && "Must have a load instruction");
setDebugLocFromInst(Builder, LI);
for (unsigned Part = 0; Part < UF; ++Part) {
// Calculate the pointer for the specific unroll-part.
Value *PartPtr =
Builder.CreateGEP(nullptr, Ptr, Builder.getInt32(Part * VF));
if (Reverse) {
// If the address is consecutive but reversed, then the
// wide load needs to start at the last vector element.
PartPtr = Builder.CreateGEP(nullptr, Ptr, Builder.getInt32(-Part * VF));
PartPtr = Builder.CreateGEP(nullptr, PartPtr, Builder.getInt32(1 - VF));
Mask[Part] = reverseVector(Mask[Part]);
}
Instruction* NewLI;
Value *VecPtr = Builder.CreateBitCast(PartPtr,
DataTy->getPointerTo(AddressSpace));
if (Legal->isMaskRequired(LI))
NewLI = Builder.CreateMaskedLoad(VecPtr, Alignment, Mask[Part],
UndefValue::get(DataTy),
"wide.masked.load");
else
NewLI = Builder.CreateAlignedLoad(VecPtr, Alignment, "wide.load");
propagateMetadata(NewLI, LI);
Entry[Part] = Reverse ? reverseVector(NewLI) : NewLI;
}
}
void InnerLoopVectorizer::scalarizeInstruction(Instruction *Instr, bool IfPredicateStore) {
assert(!Instr->getType()->isAggregateType() && "Can't handle vectors");
// Holds vector parameters or scalars, in case of uniform vals.
SmallVector<VectorParts, 4> Params;
setDebugLocFromInst(Builder, Instr);
// Find all of the vectorized parameters.
for (unsigned op = 0, e = Instr->getNumOperands(); op != e; ++op) {
Value *SrcOp = Instr->getOperand(op);
// If we are accessing the old induction variable, use the new one.
if (SrcOp == OldInduction) {
Params.push_back(getVectorValue(SrcOp));
continue;
}
// Try using previously calculated values.
Instruction *SrcInst = dyn_cast<Instruction>(SrcOp);
// If the src is an instruction that appeared earlier in the basic block
// then it should already be vectorized.
if (SrcInst && OrigLoop->contains(SrcInst)) {
assert(WidenMap.has(SrcInst) && "Source operand is unavailable");
// The parameter is a vector value from earlier.
Params.push_back(WidenMap.get(SrcInst));
} else {
// The parameter is a scalar from outside the loop. Maybe even a constant.
VectorParts Scalars;
Scalars.append(UF, SrcOp);
Params.push_back(Scalars);
}
}
assert(Params.size() == Instr->getNumOperands() &&
"Invalid number of operands");
// Does this instruction return a value ?
bool IsVoidRetTy = Instr->getType()->isVoidTy();
Value *UndefVec = IsVoidRetTy ? nullptr :
UndefValue::get(VectorType::get(Instr->getType(), VF));
// Create a new entry in the WidenMap and initialize it to Undef or Null.
VectorParts &VecResults = WidenMap.splat(Instr, UndefVec);
Instruction *InsertPt = Builder.GetInsertPoint();
BasicBlock *IfBlock = Builder.GetInsertBlock();
BasicBlock *CondBlock = nullptr;
VectorParts Cond;
Loop *VectorLp = nullptr;
if (IfPredicateStore) {
assert(Instr->getParent()->getSinglePredecessor() &&
"Only support single predecessor blocks");
Cond = createEdgeMask(Instr->getParent()->getSinglePredecessor(),
Instr->getParent());
VectorLp = LI->getLoopFor(IfBlock);
assert(VectorLp && "Must have a loop for this block");
}
// For each vector unroll 'part':
for (unsigned Part = 0; Part < UF; ++Part) {
// For each scalar that we create:
for (unsigned Width = 0; Width < VF; ++Width) {
// Start if-block.
Value *Cmp = nullptr;
if (IfPredicateStore) {
Cmp = Builder.CreateExtractElement(Cond[Part], Builder.getInt32(Width));
Cmp = Builder.CreateICmp(ICmpInst::ICMP_EQ, Cmp, ConstantInt::get(Cmp->getType(), 1));
CondBlock = IfBlock->splitBasicBlock(InsertPt, "cond.store");
LoopVectorBody.push_back(CondBlock);
VectorLp->addBasicBlockToLoop(CondBlock, *LI);
// Update Builder with newly created basic block.
Builder.SetInsertPoint(InsertPt);
}
Instruction *Cloned = Instr->clone();
if (!IsVoidRetTy)
Cloned->setName(Instr->getName() + ".cloned");
// Replace the operands of the cloned instructions with extracted scalars.
for (unsigned op = 0, e = Instr->getNumOperands(); op != e; ++op) {
Value *Op = Params[op][Part];
// Param is a vector. Need to extract the right lane.
if (Op->getType()->isVectorTy())
Op = Builder.CreateExtractElement(Op, Builder.getInt32(Width));
Cloned->setOperand(op, Op);
}
// Place the cloned scalar in the new loop.
Builder.Insert(Cloned);
// If the original scalar returns a value we need to place it in a vector
// so that future users will be able to use it.
if (!IsVoidRetTy)
VecResults[Part] = Builder.CreateInsertElement(VecResults[Part], Cloned,
Builder.getInt32(Width));
// End if-block.
if (IfPredicateStore) {
BasicBlock *NewIfBlock = CondBlock->splitBasicBlock(InsertPt, "else");
LoopVectorBody.push_back(NewIfBlock);
VectorLp->addBasicBlockToLoop(NewIfBlock, *LI);
Builder.SetInsertPoint(InsertPt);
ReplaceInstWithInst(IfBlock->getTerminator(),
BranchInst::Create(CondBlock, NewIfBlock, Cmp));
IfBlock = NewIfBlock;
}
}
}
}
static Instruction *getFirstInst(Instruction *FirstInst, Value *V,
Instruction *Loc) {
if (FirstInst)
return FirstInst;
if (Instruction *I = dyn_cast<Instruction>(V))
return I->getParent() == Loc->getParent() ? I : nullptr;
return nullptr;
}
std::pair<Instruction *, Instruction *>
InnerLoopVectorizer::addStrideCheck(Instruction *Loc) {
Instruction *tnullptr = nullptr;
if (!Legal->mustCheckStrides())
return std::pair<Instruction *, Instruction *>(tnullptr, tnullptr);
IRBuilder<> ChkBuilder(Loc);
// Emit checks.
Value *Check = nullptr;
Instruction *FirstInst = nullptr;
for (SmallPtrSet<Value *, 8>::iterator SI = Legal->strides_begin(),
SE = Legal->strides_end();
SI != SE; ++SI) {
Value *Ptr = stripIntegerCast(*SI);
Value *C = ChkBuilder.CreateICmpNE(Ptr, ConstantInt::get(Ptr->getType(), 1),
"stride.chk");
// Store the first instruction we create.
FirstInst = getFirstInst(FirstInst, C, Loc);
if (Check)
Check = ChkBuilder.CreateOr(Check, C);
else
Check = C;
}
// We have to do this trickery because the IRBuilder might fold the check to a
// constant expression in which case there is no Instruction anchored in a
// the block.
LLVMContext &Ctx = Loc->getContext();
Instruction *TheCheck =
BinaryOperator::CreateAnd(Check, ConstantInt::getTrue(Ctx));
ChkBuilder.Insert(TheCheck, "stride.not.one");
FirstInst = getFirstInst(FirstInst, TheCheck, Loc);
return std::make_pair(FirstInst, TheCheck);
}
void InnerLoopVectorizer::createEmptyLoop() {
/*
In this function we generate a new loop. The new loop will contain
the vectorized instructions while the old loop will continue to run the
scalar remainder.
[ ] <-- Back-edge taken count overflow check.
/ |
/ v
| [ ] <-- vector loop bypass (may consist of multiple blocks).
| / |
| / v
|| [ ] <-- vector pre header.
|| |
|| v
|| [ ] \
|| [ ]_| <-- vector loop.
|| |
| \ v
| >[ ] <--- middle-block.
| / |
| / v
-|- >[ ] <--- new preheader.
| |
| v
| [ ] \
| [ ]_| <-- old scalar loop to handle remainder.
\ |
\ v
>[ ] <-- exit block.
...
*/
BasicBlock *OldBasicBlock = OrigLoop->getHeader();
BasicBlock *VectorPH = OrigLoop->getLoopPreheader();
BasicBlock *ExitBlock = OrigLoop->getExitBlock();
assert(VectorPH && "Invalid loop structure");
assert(ExitBlock && "Must have an exit block");
// Some loops have a single integer induction variable, while other loops
// don't. One example is c++ iterators that often have multiple pointer
// induction variables. In the code below we also support a case where we
// don't have a single induction variable.
OldInduction = Legal->getInduction();
Type *IdxTy = Legal->getWidestInductionType();
// Find the loop boundaries.
const SCEV *ExitCount = SE->getBackedgeTakenCount(OrigLoop);
assert(ExitCount != SE->getCouldNotCompute() && "Invalid loop count");
// The exit count might have the type of i64 while the phi is i32. This can
// happen if we have an induction variable that is sign extended before the
// compare. The only way that we get a backedge taken count is that the
// induction variable was signed and as such will not overflow. In such a case
// truncation is legal.
if (ExitCount->getType()->getPrimitiveSizeInBits() >
IdxTy->getPrimitiveSizeInBits())
ExitCount = SE->getTruncateOrNoop(ExitCount, IdxTy);
const SCEV *BackedgeTakeCount = SE->getNoopOrZeroExtend(ExitCount, IdxTy);
// Get the total trip count from the count by adding 1.
ExitCount = SE->getAddExpr(BackedgeTakeCount,
SE->getConstant(BackedgeTakeCount->getType(), 1));
const DataLayout &DL = OldBasicBlock->getModule()->getDataLayout();
// Expand the trip count and place the new instructions in the preheader.
// Notice that the pre-header does not change, only the loop body.
SCEVExpander Exp(*SE, DL, "induction");
// We need to test whether the backedge-taken count is uint##_max. Adding one
// to it will cause overflow and an incorrect loop trip count in the vector
// body. In case of overflow we want to directly jump to the scalar remainder
// loop.
Value *BackedgeCount =
Exp.expandCodeFor(BackedgeTakeCount, BackedgeTakeCount->getType(),
VectorPH->getTerminator());
if (BackedgeCount->getType()->isPointerTy())
BackedgeCount = CastInst::CreatePointerCast(BackedgeCount, IdxTy,
"backedge.ptrcnt.to.int",
VectorPH->getTerminator());
Instruction *CheckBCOverflow =
CmpInst::Create(Instruction::ICmp, CmpInst::ICMP_EQ, BackedgeCount,
Constant::getAllOnesValue(BackedgeCount->getType()),
"backedge.overflow", VectorPH->getTerminator());
// The loop index does not have to start at Zero. Find the original start
// value from the induction PHI node. If we don't have an induction variable
// then we know that it starts at zero.
Builder.SetInsertPoint(VectorPH->getTerminator());
Value *StartIdx = ExtendedIdx =
OldInduction
? Builder.CreateZExt(OldInduction->getIncomingValueForBlock(VectorPH),
IdxTy)
: ConstantInt::get(IdxTy, 0);
// Count holds the overall loop count (N).
Value *Count = Exp.expandCodeFor(ExitCount, ExitCount->getType(),
VectorPH->getTerminator());
LoopBypassBlocks.push_back(VectorPH);
// Split the single block loop into the two loop structure described above.
BasicBlock *VecBody =
VectorPH->splitBasicBlock(VectorPH->getTerminator(), "vector.body");
BasicBlock *MiddleBlock =
VecBody->splitBasicBlock(VecBody->getTerminator(), "middle.block");
BasicBlock *ScalarPH =
MiddleBlock->splitBasicBlock(MiddleBlock->getTerminator(), "scalar.ph");
// Create and register the new vector loop.
Loop* Lp = new Loop();
Loop *ParentLoop = OrigLoop->getParentLoop();
// Insert the new loop into the loop nest and register the new basic blocks
// before calling any utilities such as SCEV that require valid LoopInfo.
if (ParentLoop) {
ParentLoop->addChildLoop(Lp);
ParentLoop->addBasicBlockToLoop(ScalarPH, *LI);
ParentLoop->addBasicBlockToLoop(MiddleBlock, *LI);
} else {
LI->addTopLevelLoop(Lp);
}
Lp->addBasicBlockToLoop(VecBody, *LI);
// Use this IR builder to create the loop instructions (Phi, Br, Cmp)
// inside the loop.
Builder.SetInsertPoint(VecBody->getFirstNonPHI());
// Generate the induction variable.
setDebugLocFromInst(Builder, getDebugLocFromInstOrOperands(OldInduction));
Induction = Builder.CreatePHI(IdxTy, 2, "index");
// The loop step is equal to the vectorization factor (num of SIMD elements)
// times the unroll factor (num of SIMD instructions).
Constant *Step = ConstantInt::get(IdxTy, VF * UF);
// Generate code to check that the loop's trip count that we computed by
// adding one to the backedge-taken count will not overflow.
BasicBlock *NewVectorPH =
VectorPH->splitBasicBlock(VectorPH->getTerminator(), "overflow.checked");
if (ParentLoop)
ParentLoop->addBasicBlockToLoop(NewVectorPH, *LI);
ReplaceInstWithInst(
VectorPH->getTerminator(),
BranchInst::Create(ScalarPH, NewVectorPH, CheckBCOverflow));
VectorPH = NewVectorPH;
// This is the IR builder that we use to add all of the logic for bypassing
// the new vector loop.
IRBuilder<> BypassBuilder(VectorPH->getTerminator());
setDebugLocFromInst(BypassBuilder,
getDebugLocFromInstOrOperands(OldInduction));
// We may need to extend the index in case there is a type mismatch.
// We know that the count starts at zero and does not overflow.
if (Count->getType() != IdxTy) {
// The exit count can be of pointer type. Convert it to the correct
// integer type.
if (ExitCount->getType()->isPointerTy())
Count = BypassBuilder.CreatePointerCast(Count, IdxTy, "ptrcnt.to.int");
else
Count = BypassBuilder.CreateZExtOrTrunc(Count, IdxTy, "cnt.cast");
}
// Add the start index to the loop count to get the new end index.
Value *IdxEnd = BypassBuilder.CreateAdd(Count, StartIdx, "end.idx");
// Now we need to generate the expression for N - (N % VF), which is
// the part that the vectorized body will execute.
Value *R = BypassBuilder.CreateURem(Count, Step, "n.mod.vf");
Value *CountRoundDown = BypassBuilder.CreateSub(Count, R, "n.vec");
Value *IdxEndRoundDown = BypassBuilder.CreateAdd(CountRoundDown, StartIdx,
"end.idx.rnd.down");
// Now, compare the new count to zero. If it is zero skip the vector loop and
// jump to the scalar loop.
Value *Cmp =
BypassBuilder.CreateICmpEQ(IdxEndRoundDown, StartIdx, "cmp.zero");
NewVectorPH =
VectorPH->splitBasicBlock(VectorPH->getTerminator(), "vector.ph");
if (ParentLoop)
ParentLoop->addBasicBlockToLoop(NewVectorPH, *LI);
LoopBypassBlocks.push_back(VectorPH);
ReplaceInstWithInst(VectorPH->getTerminator(),
BranchInst::Create(MiddleBlock, NewVectorPH, Cmp));
VectorPH = NewVectorPH;
// Generate the code to check that the strides we assumed to be one are really
// one. We want the new basic block to start at the first instruction in a
// sequence of instructions that form a check.
Instruction *StrideCheck;
Instruction *FirstCheckInst;
std::tie(FirstCheckInst, StrideCheck) =
addStrideCheck(VectorPH->getTerminator());
if (StrideCheck) {
AddedSafetyChecks = true;
// Create a new block containing the stride check.
VectorPH->setName("vector.stridecheck");
NewVectorPH =
VectorPH->splitBasicBlock(VectorPH->getTerminator(), "vector.ph");
if (ParentLoop)
ParentLoop->addBasicBlockToLoop(NewVectorPH, *LI);
LoopBypassBlocks.push_back(VectorPH);
// Replace the branch into the memory check block with a conditional branch
// for the "few elements case".
ReplaceInstWithInst(
VectorPH->getTerminator(),
BranchInst::Create(MiddleBlock, NewVectorPH, StrideCheck));
VectorPH = NewVectorPH;
}
// Generate the code that checks in runtime if arrays overlap. We put the
// checks into a separate block to make the more common case of few elements
// faster.
Instruction *MemRuntimeCheck;
std::tie(FirstCheckInst, MemRuntimeCheck) =
Legal->getLAI()->addRuntimeCheck(VectorPH->getTerminator());
if (MemRuntimeCheck) {
AddedSafetyChecks = true;
// Create a new block containing the memory check.
VectorPH->setName("vector.memcheck");
NewVectorPH =
VectorPH->splitBasicBlock(VectorPH->getTerminator(), "vector.ph");
if (ParentLoop)
ParentLoop->addBasicBlockToLoop(NewVectorPH, *LI);
LoopBypassBlocks.push_back(VectorPH);
// Replace the branch into the memory check block with a conditional branch
// for the "few elements case".
ReplaceInstWithInst(
VectorPH->getTerminator(),
BranchInst::Create(MiddleBlock, NewVectorPH, MemRuntimeCheck));
VectorPH = NewVectorPH;
}
// We are going to resume the execution of the scalar loop.
// Go over all of the induction variables that we found and fix the
// PHIs that are left in the scalar version of the loop.
// The starting values of PHI nodes depend on the counter of the last
// iteration in the vectorized loop.
// If we come from a bypass edge then we need to start from the original
// start value.
// This variable saves the new starting index for the scalar loop.
PHINode *ResumeIndex = nullptr;
LoopVectorizationLegality::InductionList::iterator I, E;
LoopVectorizationLegality::InductionList *List = Legal->getInductionVars();
// Set builder to point to last bypass block.
BypassBuilder.SetInsertPoint(LoopBypassBlocks.back()->getTerminator());
for (I = List->begin(), E = List->end(); I != E; ++I) {
PHINode *OrigPhi = I->first;
LoopVectorizationLegality::InductionInfo II = I->second;
Type *ResumeValTy = (OrigPhi == OldInduction) ? IdxTy : OrigPhi->getType();
PHINode *ResumeVal = PHINode::Create(ResumeValTy, 2, "resume.val",
MiddleBlock->getTerminator());
// We might have extended the type of the induction variable but we need a
// truncated version for the scalar loop.
PHINode *TruncResumeVal = (OrigPhi == OldInduction) ?
PHINode::Create(OrigPhi->getType(), 2, "trunc.resume.val",
MiddleBlock->getTerminator()) : nullptr;
// Create phi nodes to merge from the backedge-taken check block.
PHINode *BCResumeVal = PHINode::Create(ResumeValTy, 3, "bc.resume.val",
ScalarPH->getTerminator());
BCResumeVal->addIncoming(ResumeVal, MiddleBlock);
PHINode *BCTruncResumeVal = nullptr;
if (OrigPhi == OldInduction) {
BCTruncResumeVal =
PHINode::Create(OrigPhi->getType(), 2, "bc.trunc.resume.val",
ScalarPH->getTerminator());
BCTruncResumeVal->addIncoming(TruncResumeVal, MiddleBlock);
}
Value *EndValue = nullptr;
switch (II.IK) {
case LoopVectorizationLegality::IK_NoInduction:
llvm_unreachable("Unknown induction");
case LoopVectorizationLegality::IK_IntInduction: {
// Handle the integer induction counter.
assert(OrigPhi->getType()->isIntegerTy() && "Invalid type");
// We have the canonical induction variable.
if (OrigPhi == OldInduction) {
// Create a truncated version of the resume value for the scalar loop,
// we might have promoted the type to a larger width.
EndValue =
BypassBuilder.CreateTrunc(IdxEndRoundDown, OrigPhi->getType());
// The new PHI merges the original incoming value, in case of a bypass,
// or the value at the end of the vectorized loop.
for (unsigned I = 1, E = LoopBypassBlocks.size(); I != E; ++I)
TruncResumeVal->addIncoming(II.StartValue, LoopBypassBlocks[I]);
TruncResumeVal->addIncoming(EndValue, VecBody);
BCTruncResumeVal->addIncoming(II.StartValue, LoopBypassBlocks[0]);
// We know what the end value is.
EndValue = IdxEndRoundDown;
// We also know which PHI node holds it.
ResumeIndex = ResumeVal;
break;
}
// Not the canonical induction variable - add the vector loop count to the
// start value.
Value *CRD = BypassBuilder.CreateSExtOrTrunc(CountRoundDown,
II.StartValue->getType(),
"cast.crd");
EndValue = II.transform(BypassBuilder, CRD);
EndValue->setName("ind.end");
break;
}
case LoopVectorizationLegality::IK_PtrInduction: {
Value *CRD = BypassBuilder.CreateSExtOrTrunc(CountRoundDown,
II.StepValue->getType(),
"cast.crd");
EndValue = II.transform(BypassBuilder, CRD);
EndValue->setName("ptr.ind.end");
break;
}
}// end of case
// The new PHI merges the original incoming value, in case of a bypass,
// or the value at the end of the vectorized loop.
for (unsigned I = 1, E = LoopBypassBlocks.size(); I != E; ++I) {
if (OrigPhi == OldInduction)
ResumeVal->addIncoming(StartIdx, LoopBypassBlocks[I]);
else
ResumeVal->addIncoming(II.StartValue, LoopBypassBlocks[I]);
}
ResumeVal->addIncoming(EndValue, VecBody);
// Fix the scalar body counter (PHI node).
unsigned BlockIdx = OrigPhi->getBasicBlockIndex(ScalarPH);
// The old induction's phi node in the scalar body needs the truncated
// value.
if (OrigPhi == OldInduction) {
BCResumeVal->addIncoming(StartIdx, LoopBypassBlocks[0]);
OrigPhi->setIncomingValue(BlockIdx, BCTruncResumeVal);
} else {
BCResumeVal->addIncoming(II.StartValue, LoopBypassBlocks[0]);
OrigPhi->setIncomingValue(BlockIdx, BCResumeVal);
}
}
// If we are generating a new induction variable then we also need to
// generate the code that calculates the exit value. This value is not
// simply the end of the counter because we may skip the vectorized body
// in case of a runtime check.
if (!OldInduction){
assert(!ResumeIndex && "Unexpected resume value found");
ResumeIndex = PHINode::Create(IdxTy, 2, "new.indc.resume.val",
MiddleBlock->getTerminator());
for (unsigned I = 1, E = LoopBypassBlocks.size(); I != E; ++I)
ResumeIndex->addIncoming(StartIdx, LoopBypassBlocks[I]);
ResumeIndex->addIncoming(IdxEndRoundDown, VecBody);
}
// Make sure that we found the index where scalar loop needs to continue.
assert(ResumeIndex && ResumeIndex->getType()->isIntegerTy() &&
"Invalid resume Index");
// Add a check in the middle block to see if we have completed
// all of the iterations in the first vector loop.
// If (N - N%VF) == N, then we *don't* need to run the remainder.
Value *CmpN = CmpInst::Create(Instruction::ICmp, CmpInst::ICMP_EQ, IdxEnd,
ResumeIndex, "cmp.n",
MiddleBlock->getTerminator());
ReplaceInstWithInst(MiddleBlock->getTerminator(),
BranchInst::Create(ExitBlock, ScalarPH, CmpN));
// Create i+1 and fill the PHINode.
Value *NextIdx = Builder.CreateAdd(Induction, Step, "index.next");
Induction->addIncoming(StartIdx, VectorPH);
Induction->addIncoming(NextIdx, VecBody);
// Create the compare.
Value *ICmp = Builder.CreateICmpEQ(NextIdx, IdxEndRoundDown);
Builder.CreateCondBr(ICmp, MiddleBlock, VecBody);
// Now we have two terminators. Remove the old one from the block.
VecBody->getTerminator()->eraseFromParent();
// Get ready to start creating new instructions into the vectorized body.
Builder.SetInsertPoint(VecBody->getFirstInsertionPt());
// Save the state.
LoopVectorPreHeader = VectorPH;
LoopScalarPreHeader = ScalarPH;
LoopMiddleBlock = MiddleBlock;
LoopExitBlock = ExitBlock;
LoopVectorBody.push_back(VecBody);
LoopScalarBody = OldBasicBlock;
LoopVectorizeHints Hints(Lp, true);
Hints.setAlreadyVectorized();
}
namespace {
struct CSEDenseMapInfo {
static bool canHandle(Instruction *I) {
return isa<InsertElementInst>(I) || isa<ExtractElementInst>(I) ||
isa<ShuffleVectorInst>(I) || isa<GetElementPtrInst>(I);
}
static inline Instruction *getEmptyKey() {
return DenseMapInfo<Instruction *>::getEmptyKey();
}
static inline Instruction *getTombstoneKey() {
return DenseMapInfo<Instruction *>::getTombstoneKey();
}
static unsigned getHashValue(Instruction *I) {
assert(canHandle(I) && "Unknown instruction!");
return hash_combine(I->getOpcode(), hash_combine_range(I->value_op_begin(),
I->value_op_end()));
}
static bool isEqual(Instruction *LHS, Instruction *RHS) {
if (LHS == getEmptyKey() || RHS == getEmptyKey() ||
LHS == getTombstoneKey() || RHS == getTombstoneKey())
return LHS == RHS;
return LHS->isIdenticalTo(RHS);
}
};
}
/// \brief Check whether this block is a predicated block.
/// Due to if predication of stores we might create a sequence of "if(pred) a[i]
/// = ...; " blocks. We start with one vectorized basic block. For every
/// conditional block we split this vectorized block. Therefore, every second
/// block will be a predicated one.
static bool isPredicatedBlock(unsigned BlockNum) {
return BlockNum % 2;
}
///\brief Perform cse of induction variable instructions.
static void cse(SmallVector<BasicBlock *, 4> &BBs) {
// Perform simple cse.
SmallDenseMap<Instruction *, Instruction *, 4, CSEDenseMapInfo> CSEMap;
for (unsigned i = 0, e = BBs.size(); i != e; ++i) {
BasicBlock *BB = BBs[i];
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E;) {
Instruction *In = I++;
if (!CSEDenseMapInfo::canHandle(In))
continue;
// Check if we can replace this instruction with any of the
// visited instructions.
if (Instruction *V = CSEMap.lookup(In)) {
In->replaceAllUsesWith(V);
In->eraseFromParent();
continue;
}
// Ignore instructions in conditional blocks. We create "if (pred) a[i] =
// ...;" blocks for predicated stores. Every second block is a predicated
// block.
if (isPredicatedBlock(i))
continue;
CSEMap[In] = In;
}
}
}
/// \brief Adds a 'fast' flag to floating point operations.
static Value *addFastMathFlag(Value *V) {
if (isa<FPMathOperator>(V)){
FastMathFlags Flags;
Flags.setUnsafeAlgebra();
cast<Instruction>(V)->setFastMathFlags(Flags);
}
return V;
}
/// Estimate the overhead of scalarizing a value. Insert and Extract are set if
/// the result needs to be inserted and/or extracted from vectors.
static unsigned getScalarizationOverhead(Type *Ty, bool Insert, bool Extract,
const TargetTransformInfo &TTI) {
if (Ty->isVoidTy())
return 0;
assert(Ty->isVectorTy() && "Can only scalarize vectors");
unsigned Cost = 0;
for (int i = 0, e = Ty->getVectorNumElements(); i < e; ++i) {
if (Insert)
Cost += TTI.getVectorInstrCost(Instruction::InsertElement, Ty, i);
if (Extract)
Cost += TTI.getVectorInstrCost(Instruction::ExtractElement, Ty, i);
}
return Cost;
}
// Estimate cost of a call instruction CI if it were vectorized with factor VF.
// Return the cost of the instruction, including scalarization overhead if it's
// needed. The flag NeedToScalarize shows if the call needs to be scalarized -
// i.e. either vector version isn't available, or is too expensive.
static unsigned getVectorCallCost(CallInst *CI, unsigned VF,
const TargetTransformInfo &TTI,
const TargetLibraryInfo *TLI,
bool &NeedToScalarize) {
Function *F = CI->getCalledFunction();
StringRef FnName = CI->getCalledFunction()->getName();
Type *ScalarRetTy = CI->getType();
SmallVector<Type *, 4> Tys, ScalarTys;
for (auto &ArgOp : CI->arg_operands())
ScalarTys.push_back(ArgOp->getType());
// Estimate cost of scalarized vector call. The source operands are assumed
// to be vectors, so we need to extract individual elements from there,
// execute VF scalar calls, and then gather the result into the vector return
// value.
unsigned ScalarCallCost = TTI.getCallInstrCost(F, ScalarRetTy, ScalarTys);
if (VF == 1)
return ScalarCallCost;
// Compute corresponding vector type for return value and arguments.
Type *RetTy = ToVectorTy(ScalarRetTy, VF);
for (unsigned i = 0, ie = ScalarTys.size(); i != ie; ++i)
Tys.push_back(ToVectorTy(ScalarTys[i], VF));
// Compute costs of unpacking argument values for the scalar calls and
// packing the return values to a vector.
unsigned ScalarizationCost =
getScalarizationOverhead(RetTy, true, false, TTI);
for (unsigned i = 0, ie = Tys.size(); i != ie; ++i)
ScalarizationCost += getScalarizationOverhead(Tys[i], false, true, TTI);
unsigned Cost = ScalarCallCost * VF + ScalarizationCost;
// If we can't emit a vector call for this function, then the currently found
// cost is the cost we need to return.
NeedToScalarize = true;
if (!TLI || !TLI->isFunctionVectorizable(FnName, VF) || CI->isNoBuiltin())
return Cost;
// If the corresponding vector cost is cheaper, return its cost.
unsigned VectorCallCost = TTI.getCallInstrCost(nullptr, RetTy, Tys);
if (VectorCallCost < Cost) {
NeedToScalarize = false;
return VectorCallCost;
}
return Cost;
}
// Estimate cost of an intrinsic call instruction CI if it were vectorized with
// factor VF. Return the cost of the instruction, including scalarization
// overhead if it's needed.
static unsigned getVectorIntrinsicCost(CallInst *CI, unsigned VF,
const TargetTransformInfo &TTI,
const TargetLibraryInfo *TLI) {
Intrinsic::ID ID = getIntrinsicIDForCall(CI, TLI);
assert(ID && "Expected intrinsic call!");
Type *RetTy = ToVectorTy(CI->getType(), VF);
SmallVector<Type *, 4> Tys;
for (unsigned i = 0, ie = CI->getNumArgOperands(); i != ie; ++i)
Tys.push_back(ToVectorTy(CI->getArgOperand(i)->getType(), VF));
return TTI.getIntrinsicInstrCost(ID, RetTy, Tys);
}
void InnerLoopVectorizer::vectorizeLoop() {
//===------------------------------------------------===//
//
// Notice: any optimization or new instruction that go
// into the code below should be also be implemented in
// the cost-model.
//
//===------------------------------------------------===//
Constant *Zero = Builder.getInt32(0);
// In order to support reduction variables we need to be able to vectorize
// Phi nodes. Phi nodes have cycles, so we need to vectorize them in two
// stages. First, we create a new vector PHI node with no incoming edges.
// We use this value when we vectorize all of the instructions that use the
// PHI. Next, after all of the instructions in the block are complete we
// add the new incoming edges to the PHI. At this point all of the
// instructions in the basic block are vectorized, so we can use them to
// construct the PHI.
PhiVector RdxPHIsToFix;
// Scan the loop in a topological order to ensure that defs are vectorized
// before users.
LoopBlocksDFS DFS(OrigLoop);
DFS.perform(LI);
// Vectorize all of the blocks in the original loop.
for (LoopBlocksDFS::RPOIterator bb = DFS.beginRPO(),
be = DFS.endRPO(); bb != be; ++bb)
vectorizeBlockInLoop(*bb, &RdxPHIsToFix);
// At this point every instruction in the original loop is widened to
// a vector form. We are almost done. Now, we need to fix the PHI nodes
// that we vectorized. The PHI nodes are currently empty because we did
// not want to introduce cycles. Notice that the remaining PHI nodes
// that we need to fix are reduction variables.
// Create the 'reduced' values for each of the induction vars.
// The reduced values are the vector values that we scalarize and combine
// after the loop is finished.
for (PhiVector::iterator it = RdxPHIsToFix.begin(), e = RdxPHIsToFix.end();
it != e; ++it) {
PHINode *RdxPhi = *it;
assert(RdxPhi && "Unable to recover vectorized PHI");
// Find the reduction variable descriptor.
assert(Legal->getReductionVars()->count(RdxPhi) &&
"Unable to find the reduction variable");
RecurrenceDescriptor RdxDesc = (*Legal->getReductionVars())[RdxPhi];
RecurrenceDescriptor::RecurrenceKind RK = RdxDesc.getRecurrenceKind();
TrackingVH<Value> ReductionStartValue = RdxDesc.getRecurrenceStartValue();
Instruction *LoopExitInst = RdxDesc.getLoopExitInstr();
RecurrenceDescriptor::MinMaxRecurrenceKind MinMaxKind =
RdxDesc.getMinMaxRecurrenceKind();
setDebugLocFromInst(Builder, ReductionStartValue);
// We need to generate a reduction vector from the incoming scalar.
// To do so, we need to generate the 'identity' vector and override
// one of the elements with the incoming scalar reduction. We need
// to do it in the vector-loop preheader.
Builder.SetInsertPoint(LoopBypassBlocks[1]->getTerminator());
// This is the vector-clone of the value that leaves the loop.
VectorParts &VectorExit = getVectorValue(LoopExitInst);
Type *VecTy = VectorExit[0]->getType();
// Find the reduction identity variable. Zero for addition, or, xor,
// one for multiplication, -1 for And.
Value *Identity;
Value *VectorStart;
if (RK == RecurrenceDescriptor::RK_IntegerMinMax ||
RK == RecurrenceDescriptor::RK_FloatMinMax) {
// MinMax reduction have the start value as their identify.
if (VF == 1) {
VectorStart = Identity = ReductionStartValue;
} else {
VectorStart = Identity =
Builder.CreateVectorSplat(VF, ReductionStartValue, "minmax.ident");
}
} else {
// Handle other reduction kinds:
Constant *Iden = RecurrenceDescriptor::getRecurrenceIdentity(
RK, VecTy->getScalarType());
if (VF == 1) {
Identity = Iden;
// This vector is the Identity vector where the first element is the
// incoming scalar reduction.
VectorStart = ReductionStartValue;
} else {
Identity = ConstantVector::getSplat(VF, Iden);
// This vector is the Identity vector where the first element is the
// incoming scalar reduction.
VectorStart =
Builder.CreateInsertElement(Identity, ReductionStartValue, Zero);
}
}
// Fix the vector-loop phi.
// Reductions do not have to start at zero. They can start with
// any loop invariant values.
VectorParts &VecRdxPhi = WidenMap.get(RdxPhi);
BasicBlock *Latch = OrigLoop->getLoopLatch();
Value *LoopVal = RdxPhi->getIncomingValueForBlock(Latch);
VectorParts &Val = getVectorValue(LoopVal);
for (unsigned part = 0; part < UF; ++part) {
// Make sure to add the reduction stat value only to the
// first unroll part.
Value *StartVal = (part == 0) ? VectorStart : Identity;
cast<PHINode>(VecRdxPhi[part])->addIncoming(StartVal,
LoopVectorPreHeader);
cast<PHINode>(VecRdxPhi[part])->addIncoming(Val[part],
LoopVectorBody.back());
}
// Before each round, move the insertion point right between
// the PHIs and the values we are going to write.
// This allows us to write both PHINodes and the extractelement
// instructions.
Builder.SetInsertPoint(LoopMiddleBlock->getFirstInsertionPt());
VectorParts RdxParts;
setDebugLocFromInst(Builder, LoopExitInst);
for (unsigned part = 0; part < UF; ++part) {
// This PHINode contains the vectorized reduction variable, or
// the initial value vector, if we bypass the vector loop.
VectorParts &RdxExitVal = getVectorValue(LoopExitInst);
PHINode *NewPhi = Builder.CreatePHI(VecTy, 2, "rdx.vec.exit.phi");
Value *StartVal = (part == 0) ? VectorStart : Identity;
for (unsigned I = 1, E = LoopBypassBlocks.size(); I != E; ++I)
NewPhi->addIncoming(StartVal, LoopBypassBlocks[I]);
NewPhi->addIncoming(RdxExitVal[part],
LoopVectorBody.back());
RdxParts.push_back(NewPhi);
}
// Reduce all of the unrolled parts into a single vector.
Value *ReducedPartRdx = RdxParts[0];
unsigned Op = RecurrenceDescriptor::getRecurrenceBinOp(RK);
setDebugLocFromInst(Builder, ReducedPartRdx);
for (unsigned part = 1; part < UF; ++part) {
if (Op != Instruction::ICmp && Op != Instruction::FCmp)
// Floating point operations had to be 'fast' to enable the reduction.
ReducedPartRdx = addFastMathFlag(
Builder.CreateBinOp((Instruction::BinaryOps)Op, RdxParts[part],
ReducedPartRdx, "bin.rdx"));
else
ReducedPartRdx = RecurrenceDescriptor::createMinMaxOp(
Builder, MinMaxKind, ReducedPartRdx, RdxParts[part]);
}
if (VF > 1) {
// VF is a power of 2 so we can emit the reduction using log2(VF) shuffles
// and vector ops, reducing the set of values being computed by half each
// round.
assert(isPowerOf2_32(VF) &&
"Reduction emission only supported for pow2 vectors!");
Value *TmpVec = ReducedPartRdx;
SmallVector<Constant*, 32> ShuffleMask(VF, nullptr);
for (unsigned i = VF; i != 1; i >>= 1) {
// Move the upper half of the vector to the lower half.
for (unsigned j = 0; j != i/2; ++j)
ShuffleMask[j] = Builder.getInt32(i/2 + j);
// Fill the rest of the mask with undef.
std::fill(&ShuffleMask[i/2], ShuffleMask.end(),
UndefValue::get(Builder.getInt32Ty()));
Value *Shuf =
Builder.CreateShuffleVector(TmpVec,
UndefValue::get(TmpVec->getType()),
ConstantVector::get(ShuffleMask),
"rdx.shuf");
if (Op != Instruction::ICmp && Op != Instruction::FCmp)
// Floating point operations had to be 'fast' to enable the reduction.
TmpVec = addFastMathFlag(Builder.CreateBinOp(
(Instruction::BinaryOps)Op, TmpVec, Shuf, "bin.rdx"));
else
TmpVec = RecurrenceDescriptor::createMinMaxOp(Builder, MinMaxKind,
TmpVec, Shuf);
}
// The result is in the first element of the vector.
ReducedPartRdx = Builder.CreateExtractElement(TmpVec,
Builder.getInt32(0));
}
// Create a phi node that merges control-flow from the backedge-taken check
// block and the middle block.
PHINode *BCBlockPhi = PHINode::Create(RdxPhi->getType(), 2, "bc.merge.rdx",
LoopScalarPreHeader->getTerminator());
BCBlockPhi->addIncoming(ReductionStartValue, LoopBypassBlocks[0]);
BCBlockPhi->addIncoming(ReducedPartRdx, LoopMiddleBlock);
// Now, we need to fix the users of the reduction variable
// inside and outside of the scalar remainder loop.
// We know that the loop is in LCSSA form. We need to update the
// PHI nodes in the exit blocks.
for (BasicBlock::iterator LEI = LoopExitBlock->begin(),
LEE = LoopExitBlock->end(); LEI != LEE; ++LEI) {
PHINode *LCSSAPhi = dyn_cast<PHINode>(LEI);
if (!LCSSAPhi) break;
// All PHINodes need to have a single entry edge, or two if
// we already fixed them.
assert(LCSSAPhi->getNumIncomingValues() < 3 && "Invalid LCSSA PHI");
// We found our reduction value exit-PHI. Update it with the
// incoming bypass edge.
if (LCSSAPhi->getIncomingValue(0) == LoopExitInst) {
// Add an edge coming from the bypass.
LCSSAPhi->addIncoming(ReducedPartRdx, LoopMiddleBlock);
break;
}
}// end of the LCSSA phi scan.
// Fix the scalar loop reduction variable with the incoming reduction sum
// from the vector body and from the backedge value.
int IncomingEdgeBlockIdx =
(RdxPhi)->getBasicBlockIndex(OrigLoop->getLoopLatch());
assert(IncomingEdgeBlockIdx >= 0 && "Invalid block index");
// Pick the other block.
int SelfEdgeBlockIdx = (IncomingEdgeBlockIdx ? 0 : 1);
(RdxPhi)->setIncomingValue(SelfEdgeBlockIdx, BCBlockPhi);
(RdxPhi)->setIncomingValue(IncomingEdgeBlockIdx, LoopExitInst);
}// end of for each redux variable.
fixLCSSAPHIs();
// Remove redundant induction instructions.
cse(LoopVectorBody);
}
void InnerLoopVectorizer::fixLCSSAPHIs() {
for (BasicBlock::iterator LEI = LoopExitBlock->begin(),
LEE = LoopExitBlock->end(); LEI != LEE; ++LEI) {
PHINode *LCSSAPhi = dyn_cast<PHINode>(LEI);
if (!LCSSAPhi) break;
if (LCSSAPhi->getNumIncomingValues() == 1)
LCSSAPhi->addIncoming(UndefValue::get(LCSSAPhi->getType()),
LoopMiddleBlock);
}
}
InnerLoopVectorizer::VectorParts
InnerLoopVectorizer::createEdgeMask(BasicBlock *Src, BasicBlock *Dst) {
assert(std::find(pred_begin(Dst), pred_end(Dst), Src) != pred_end(Dst) &&
"Invalid edge");
// Look for cached value.
std::pair<BasicBlock*, BasicBlock*> Edge(Src, Dst);
EdgeMaskCache::iterator ECEntryIt = MaskCache.find(Edge);
if (ECEntryIt != MaskCache.end())
return ECEntryIt->second;
VectorParts SrcMask = createBlockInMask(Src);
// The terminator has to be a branch inst!
BranchInst *BI = dyn_cast<BranchInst>(Src->getTerminator());
assert(BI && "Unexpected terminator found");
if (BI->isConditional()) {
VectorParts EdgeMask = getVectorValue(BI->getCondition());
if (BI->getSuccessor(0) != Dst)
for (unsigned part = 0; part < UF; ++part)
EdgeMask[part] = Builder.CreateNot(EdgeMask[part]);
for (unsigned part = 0; part < UF; ++part)
EdgeMask[part] = Builder.CreateAnd(EdgeMask[part], SrcMask[part]);
MaskCache[Edge] = EdgeMask;
return EdgeMask;
}
MaskCache[Edge] = SrcMask;
return SrcMask;
}
InnerLoopVectorizer::VectorParts
InnerLoopVectorizer::createBlockInMask(BasicBlock *BB) {
assert(OrigLoop->contains(BB) && "Block is not a part of a loop");
// Loop incoming mask is all-one.
if (OrigLoop->getHeader() == BB) {
Value *C = ConstantInt::get(IntegerType::getInt1Ty(BB->getContext()), 1);
return getVectorValue(C);
}
// This is the block mask. We OR all incoming edges, and with zero.
Value *Zero = ConstantInt::get(IntegerType::getInt1Ty(BB->getContext()), 0);
VectorParts BlockMask = getVectorValue(Zero);
// For each pred:
for (pred_iterator it = pred_begin(BB), e = pred_end(BB); it != e; ++it) {
VectorParts EM = createEdgeMask(*it, BB);
for (unsigned part = 0; part < UF; ++part)
BlockMask[part] = Builder.CreateOr(BlockMask[part], EM[part]);
}
return BlockMask;
}
void InnerLoopVectorizer::widenPHIInstruction(Instruction *PN,
InnerLoopVectorizer::VectorParts &Entry,
unsigned UF, unsigned VF, PhiVector *PV) {
PHINode* P = cast<PHINode>(PN);
// Handle reduction variables:
if (Legal->getReductionVars()->count(P)) {
for (unsigned part = 0; part < UF; ++part) {
// This is phase one of vectorizing PHIs.
Type *VecTy = (VF == 1) ? PN->getType() :
VectorType::get(PN->getType(), VF);
Entry[part] = PHINode::Create(VecTy, 2, "vec.phi",
LoopVectorBody.back()-> getFirstInsertionPt());
}
PV->push_back(P);
return;
}
setDebugLocFromInst(Builder, P);
// Check for PHI nodes that are lowered to vector selects.
if (P->getParent() != OrigLoop->getHeader()) {
// We know that all PHIs in non-header blocks are converted into
// selects, so we don't have to worry about the insertion order and we
// can just use the builder.
// At this point we generate the predication tree. There may be
// duplications since this is a simple recursive scan, but future
// optimizations will clean it up.
unsigned NumIncoming = P->getNumIncomingValues();
// Generate a sequence of selects of the form:
// SELECT(Mask3, In3,
// SELECT(Mask2, In2,
// ( ...)))
for (unsigned In = 0; In < NumIncoming; In++) {
VectorParts Cond = createEdgeMask(P->getIncomingBlock(In),
P->getParent());
VectorParts &In0 = getVectorValue(P->getIncomingValue(In));
for (unsigned part = 0; part < UF; ++part) {
// We might have single edge PHIs (blocks) - use an identity
// 'select' for the first PHI operand.
if (In == 0)
Entry[part] = Builder.CreateSelect(Cond[part], In0[part],
In0[part]);
else
// Select between the current value and the previous incoming edge
// based on the incoming mask.
Entry[part] = Builder.CreateSelect(Cond[part], In0[part],
Entry[part], "predphi");
}
}
return;
}
// This PHINode must be an induction variable.
// Make sure that we know about it.
assert(Legal->getInductionVars()->count(P) &&
"Not an induction variable");
LoopVectorizationLegality::InductionInfo II =
Legal->getInductionVars()->lookup(P);
// FIXME: The newly created binary instructions should contain nsw/nuw flags,
// which can be found from the original scalar operations.
switch (II.IK) {
case LoopVectorizationLegality::IK_NoInduction:
llvm_unreachable("Unknown induction");
case LoopVectorizationLegality::IK_IntInduction: {
assert(P->getType() == II.StartValue->getType() && "Types must match");
Type *PhiTy = P->getType();
Value *Broadcasted;
if (P == OldInduction) {
// Handle the canonical induction variable. We might have had to
// extend the type.
Broadcasted = Builder.CreateTrunc(Induction, PhiTy);
} else {
// Handle other induction variables that are now based on the
// canonical one.
Value *NormalizedIdx = Builder.CreateSub(Induction, ExtendedIdx,
"normalized.idx");
NormalizedIdx = Builder.CreateSExtOrTrunc(NormalizedIdx, PhiTy);
Broadcasted = II.transform(Builder, NormalizedIdx);
Broadcasted->setName("offset.idx");
}
Broadcasted = getBroadcastInstrs(Broadcasted);
// After broadcasting the induction variable we need to make the vector
// consecutive by adding 0, 1, 2, etc.
for (unsigned part = 0; part < UF; ++part)
Entry[part] = getStepVector(Broadcasted, VF * part, II.StepValue);
return;
}
case LoopVectorizationLegality::IK_PtrInduction:
// Handle the pointer induction variable case.
assert(P->getType()->isPointerTy() && "Unexpected type.");
// This is the normalized GEP that starts counting at zero.
Value *NormalizedIdx =
Builder.CreateSub(Induction, ExtendedIdx, "normalized.idx");
NormalizedIdx =
Builder.CreateSExtOrTrunc(NormalizedIdx, II.StepValue->getType());
// This is the vector of results. Notice that we don't generate
// vector geps because scalar geps result in better code.
for (unsigned part = 0; part < UF; ++part) {
if (VF == 1) {
int EltIndex = part;
Constant *Idx = ConstantInt::get(NormalizedIdx->getType(), EltIndex);
Value *GlobalIdx = Builder.CreateAdd(NormalizedIdx, Idx);
Value *SclrGep = II.transform(Builder, GlobalIdx);
SclrGep->setName("next.gep");
Entry[part] = SclrGep;
continue;
}
Value *VecVal = UndefValue::get(VectorType::get(P->getType(), VF));
for (unsigned int i = 0; i < VF; ++i) {
int EltIndex = i + part * VF;
Constant *Idx = ConstantInt::get(NormalizedIdx->getType(), EltIndex);
Value *GlobalIdx = Builder.CreateAdd(NormalizedIdx, Idx);
Value *SclrGep = II.transform(Builder, GlobalIdx);
SclrGep->setName("next.gep");
VecVal = Builder.CreateInsertElement(VecVal, SclrGep,
Builder.getInt32(i),
"insert.gep");
}
Entry[part] = VecVal;
}
return;
}
}
void InnerLoopVectorizer::vectorizeBlockInLoop(BasicBlock *BB, PhiVector *PV) {
// For each instruction in the old loop.
for (BasicBlock::iterator it = BB->begin(), e = BB->end(); it != e; ++it) {
VectorParts &Entry = WidenMap.get(it);
switch (it->getOpcode()) {
case Instruction::Br:
// Nothing to do for PHIs and BR, since we already took care of the
// loop control flow instructions.
continue;
case Instruction::PHI: {
// Vectorize PHINodes.
widenPHIInstruction(it, Entry, UF, VF, PV);
continue;
}// End of PHI.
case Instruction::Add:
case Instruction::FAdd:
case Instruction::Sub:
case Instruction::FSub:
case Instruction::Mul:
case Instruction::FMul:
case Instruction::UDiv:
case Instruction::SDiv:
case Instruction::FDiv:
case Instruction::URem:
case Instruction::SRem:
case Instruction::FRem:
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor: {
// Just widen binops.
BinaryOperator *BinOp = dyn_cast<BinaryOperator>(it);
setDebugLocFromInst(Builder, BinOp);
VectorParts &A = getVectorValue(it->getOperand(0));
VectorParts &B = getVectorValue(it->getOperand(1));
// Use this vector value for all users of the original instruction.
for (unsigned Part = 0; Part < UF; ++Part) {
Value *V = Builder.CreateBinOp(BinOp->getOpcode(), A[Part], B[Part]);
if (BinaryOperator *VecOp = dyn_cast<BinaryOperator>(V))
VecOp->copyIRFlags(BinOp);
Entry[Part] = V;
}
propagateMetadata(Entry, it);
break;
}
case Instruction::Select: {
// Widen selects.
// If the selector is loop invariant we can create a select
// instruction with a scalar condition. Otherwise, use vector-select.
bool InvariantCond = SE->isLoopInvariant(SE->getSCEV(it->getOperand(0)),
OrigLoop);
setDebugLocFromInst(Builder, it);
// The condition can be loop invariant but still defined inside the
// loop. This means that we can't just use the original 'cond' value.
// We have to take the 'vectorized' value and pick the first lane.
// Instcombine will make this a no-op.
VectorParts &Cond = getVectorValue(it->getOperand(0));
VectorParts &Op0 = getVectorValue(it->getOperand(1));
VectorParts &Op1 = getVectorValue(it->getOperand(2));
Value *ScalarCond = (VF == 1) ? Cond[0] :
Builder.CreateExtractElement(Cond[0], Builder.getInt32(0));
for (unsigned Part = 0; Part < UF; ++Part) {
Entry[Part] = Builder.CreateSelect(
InvariantCond ? ScalarCond : Cond[Part],
Op0[Part],
Op1[Part]);
}
propagateMetadata(Entry, it);
break;
}
case Instruction::ICmp:
case Instruction::FCmp: {
// Widen compares. Generate vector compares.
bool FCmp = (it->getOpcode() == Instruction::FCmp);
CmpInst *Cmp = dyn_cast<CmpInst>(it);
setDebugLocFromInst(Builder, it);
VectorParts &A = getVectorValue(it->getOperand(0));
VectorParts &B = getVectorValue(it->getOperand(1));
for (unsigned Part = 0; Part < UF; ++Part) {
Value *C = nullptr;
if (FCmp)
C = Builder.CreateFCmp(Cmp->getPredicate(), A[Part], B[Part]);
else
C = Builder.CreateICmp(Cmp->getPredicate(), A[Part], B[Part]);
Entry[Part] = C;
}
propagateMetadata(Entry, it);
break;
}
case Instruction::Store:
case Instruction::Load:
vectorizeMemoryInstruction(it);
break;
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::FPToUI:
case Instruction::FPToSI:
case Instruction::FPExt:
case Instruction::PtrToInt:
case Instruction::IntToPtr:
case Instruction::SIToFP:
case Instruction::UIToFP:
case Instruction::Trunc:
case Instruction::FPTrunc:
case Instruction::BitCast: {
CastInst *CI = dyn_cast<CastInst>(it);
setDebugLocFromInst(Builder, it);
/// Optimize the special case where the source is the induction
/// variable. Notice that we can only optimize the 'trunc' case
/// because: a. FP conversions lose precision, b. sext/zext may wrap,
/// c. other casts depend on pointer size.
if (CI->getOperand(0) == OldInduction &&
it->getOpcode() == Instruction::Trunc) {
Value *ScalarCast = Builder.CreateCast(CI->getOpcode(), Induction,
CI->getType());
Value *Broadcasted = getBroadcastInstrs(ScalarCast);
LoopVectorizationLegality::InductionInfo II =
Legal->getInductionVars()->lookup(OldInduction);
Constant *Step =
ConstantInt::getSigned(CI->getType(), II.StepValue->getSExtValue());
for (unsigned Part = 0; Part < UF; ++Part)
Entry[Part] = getStepVector(Broadcasted, VF * Part, Step);
propagateMetadata(Entry, it);
break;
}
/// Vectorize casts.
Type *DestTy = (VF == 1) ? CI->getType() :
VectorType::get(CI->getType(), VF);
VectorParts &A = getVectorValue(it->getOperand(0));
for (unsigned Part = 0; Part < UF; ++Part)
Entry[Part] = Builder.CreateCast(CI->getOpcode(), A[Part], DestTy);
propagateMetadata(Entry, it);
break;
}
case Instruction::Call: {
// Ignore dbg intrinsics.
if (isa<DbgInfoIntrinsic>(it))
break;
setDebugLocFromInst(Builder, it);
Module *M = BB->getParent()->getParent();
CallInst *CI = cast<CallInst>(it);
StringRef FnName = CI->getCalledFunction()->getName();
Function *F = CI->getCalledFunction();
Type *RetTy = ToVectorTy(CI->getType(), VF);
SmallVector<Type *, 4> Tys;
for (unsigned i = 0, ie = CI->getNumArgOperands(); i != ie; ++i)
Tys.push_back(ToVectorTy(CI->getArgOperand(i)->getType(), VF));
Intrinsic::ID ID = getIntrinsicIDForCall(CI, TLI);
if (ID &&
(ID == Intrinsic::assume || ID == Intrinsic::lifetime_end ||
ID == Intrinsic::lifetime_start)) {
scalarizeInstruction(it);
break;
}
// The flag shows whether we use Intrinsic or a usual Call for vectorized
// version of the instruction.
// Is it beneficial to perform intrinsic call compared to lib call?
bool NeedToScalarize;
unsigned CallCost = getVectorCallCost(CI, VF, *TTI, TLI, NeedToScalarize);
bool UseVectorIntrinsic =
ID && getVectorIntrinsicCost(CI, VF, *TTI, TLI) <= CallCost;
if (!UseVectorIntrinsic && NeedToScalarize) {
scalarizeInstruction(it);
break;
}
for (unsigned Part = 0; Part < UF; ++Part) {
SmallVector<Value *, 4> Args;
for (unsigned i = 0, ie = CI->getNumArgOperands(); i != ie; ++i) {
Value *Arg = CI->getArgOperand(i);
// Some intrinsics have a scalar argument - don't replace it with a
// vector.
if (!UseVectorIntrinsic || !hasVectorInstrinsicScalarOpd(ID, i)) {
VectorParts &VectorArg = getVectorValue(CI->getArgOperand(i));
Arg = VectorArg[Part];
}
Args.push_back(Arg);
}
Function *VectorF;
if (UseVectorIntrinsic) {
// Use vector version of the intrinsic.
Type *TysForDecl[] = {CI->getType()};
if (VF > 1)
TysForDecl[0] = VectorType::get(CI->getType()->getScalarType(), VF);
VectorF = Intrinsic::getDeclaration(M, ID, TysForDecl);
} else {
// Use vector version of the library call.
StringRef VFnName = TLI->getVectorizedFunction(FnName, VF);
assert(!VFnName.empty() && "Vector function name is empty.");
VectorF = M->getFunction(VFnName);
if (!VectorF) {
// Generate a declaration
FunctionType *FTy = FunctionType::get(RetTy, Tys, false);
VectorF =
Function::Create(FTy, Function::ExternalLinkage, VFnName, M);
VectorF->copyAttributesFrom(F);
}
}
assert(VectorF && "Can't create vector function.");
Entry[Part] = Builder.CreateCall(VectorF, Args);
}
propagateMetadata(Entry, it);
break;
}
default:
// All other instructions are unsupported. Scalarize them.
scalarizeInstruction(it);
break;
}// end of switch.
}// end of for_each instr.
}
void InnerLoopVectorizer::updateAnalysis() {
// Forget the original basic block.
SE->forgetLoop(OrigLoop);
// Update the dominator tree information.
assert(DT->properlyDominates(LoopBypassBlocks.front(), LoopExitBlock) &&
"Entry does not dominate exit.");
for (unsigned I = 1, E = LoopBypassBlocks.size(); I != E; ++I)
DT->addNewBlock(LoopBypassBlocks[I], LoopBypassBlocks[I-1]);
DT->addNewBlock(LoopVectorPreHeader, LoopBypassBlocks.back());
// Due to if predication of stores we might create a sequence of "if(pred)
// a[i] = ...; " blocks.
for (unsigned i = 0, e = LoopVectorBody.size(); i != e; ++i) {
if (i == 0)
DT->addNewBlock(LoopVectorBody[0], LoopVectorPreHeader);
else if (isPredicatedBlock(i)) {
DT->addNewBlock(LoopVectorBody[i], LoopVectorBody[i-1]);
} else {
DT->addNewBlock(LoopVectorBody[i], LoopVectorBody[i-2]);
}
}
DT->addNewBlock(LoopMiddleBlock, LoopBypassBlocks[1]);
DT->addNewBlock(LoopScalarPreHeader, LoopBypassBlocks[0]);
DT->changeImmediateDominator(LoopScalarBody, LoopScalarPreHeader);
DT->changeImmediateDominator(LoopExitBlock, LoopBypassBlocks[0]);
DEBUG(DT->verifyDomTree());
}
/// \brief Check whether it is safe to if-convert this phi node.
///
/// Phi nodes with constant expressions that can trap are not safe to if
/// convert.
static bool canIfConvertPHINodes(BasicBlock *BB) {
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) {
PHINode *Phi = dyn_cast<PHINode>(I);
if (!Phi)
return true;
for (unsigned p = 0, e = Phi->getNumIncomingValues(); p != e; ++p)
if (Constant *C = dyn_cast<Constant>(Phi->getIncomingValue(p)))
if (C->canTrap())
return false;
}
return true;
}
bool LoopVectorizationLegality::canVectorizeWithIfConvert() {
if (!EnableIfConversion) {
emitAnalysis(VectorizationReport() << "if-conversion is disabled");
return false;
}
assert(TheLoop->getNumBlocks() > 1 && "Single block loops are vectorizable");
// A list of pointers that we can safely read and write to.
SmallPtrSet<Value *, 8> SafePointes;
// Collect safe addresses.
for (Loop::block_iterator BI = TheLoop->block_begin(),
BE = TheLoop->block_end(); BI != BE; ++BI) {
BasicBlock *BB = *BI;
if (blockNeedsPredication(BB))
continue;
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) {
if (LoadInst *LI = dyn_cast<LoadInst>(I))
SafePointes.insert(LI->getPointerOperand());
else if (StoreInst *SI = dyn_cast<StoreInst>(I))
SafePointes.insert(SI->getPointerOperand());
}
}
// Collect the blocks that need predication.
BasicBlock *Header = TheLoop->getHeader();
for (Loop::block_iterator BI = TheLoop->block_begin(),
BE = TheLoop->block_end(); BI != BE; ++BI) {
BasicBlock *BB = *BI;
// We don't support switch statements inside loops.
if (!isa<BranchInst>(BB->getTerminator())) {
emitAnalysis(VectorizationReport(BB->getTerminator())
<< "loop contains a switch statement");
return false;
}
// We must be able to predicate all blocks that need to be predicated.
if (blockNeedsPredication(BB)) {
if (!blockCanBePredicated(BB, SafePointes)) {
emitAnalysis(VectorizationReport(BB->getTerminator())
<< "control flow cannot be substituted for a select");
return false;
}
} else if (BB != Header && !canIfConvertPHINodes(BB)) {
emitAnalysis(VectorizationReport(BB->getTerminator())
<< "control flow cannot be substituted for a select");
return false;
}
}
// We can if-convert this loop.
return true;
}
bool LoopVectorizationLegality::canVectorize() {
// We must have a loop in canonical form. Loops with indirectbr in them cannot
// be canonicalized.
if (!TheLoop->getLoopPreheader()) {
emitAnalysis(
VectorizationReport() <<
"loop control flow is not understood by vectorizer");
return false;
}
// We can only vectorize innermost loops.
if (!TheLoop->empty()) {
emitAnalysis(VectorizationReport() << "loop is not the innermost loop");
return false;
}
// We must have a single backedge.
if (TheLoop->getNumBackEdges() != 1) {
emitAnalysis(
VectorizationReport() <<
"loop control flow is not understood by vectorizer");
return false;
}
// We must have a single exiting block.
if (!TheLoop->getExitingBlock()) {
emitAnalysis(
VectorizationReport() <<
"loop control flow is not understood by vectorizer");
return false;
}
// We only handle bottom-tested loops, i.e. loop in which the condition is
// checked at the end of each iteration. With that we can assume that all
// instructions in the loop are executed the same number of times.
if (TheLoop->getExitingBlock() != TheLoop->getLoopLatch()) {
emitAnalysis(
VectorizationReport() <<
"loop control flow is not understood by vectorizer");
return false;
}
// We need to have a loop header.
DEBUG(dbgs() << "LV: Found a loop: " <<
TheLoop->getHeader()->getName() << '\n');
// Check if we can if-convert non-single-bb loops.
unsigned NumBlocks = TheLoop->getNumBlocks();
if (NumBlocks != 1 && !canVectorizeWithIfConvert()) {
DEBUG(dbgs() << "LV: Can't if-convert the loop.\n");
return false;
}
// ScalarEvolution needs to be able to find the exit count.
const SCEV *ExitCount = SE->getBackedgeTakenCount(TheLoop);
if (ExitCount == SE->getCouldNotCompute()) {
emitAnalysis(VectorizationReport() <<
"could not determine number of loop iterations");
DEBUG(dbgs() << "LV: SCEV could not compute the loop exit count.\n");
return false;
}
// Check if we can vectorize the instructions and CFG in this loop.
if (!canVectorizeInstrs()) {
DEBUG(dbgs() << "LV: Can't vectorize the instructions or CFG\n");
return false;
}
// Go over each instruction and look at memory deps.
if (!canVectorizeMemory()) {
DEBUG(dbgs() << "LV: Can't vectorize due to memory conflicts\n");
return false;
}
// Collect all of the variables that remain uniform after vectorization.
collectLoopUniforms();
DEBUG(dbgs() << "LV: We can vectorize this loop"
<< (LAI->getRuntimePointerChecking()->Need
? " (with a runtime bound check)"
: "")
<< "!\n");
// Analyze interleaved memory accesses.
if (EnableInterleavedMemAccesses)
InterleaveInfo.analyzeInterleaving(Strides);
// Okay! We can vectorize. At this point we don't have any other mem analysis
// which may limit our maximum vectorization factor, so just return true with
// no restrictions.
return true;
}
static Type *convertPointerToIntegerType(const DataLayout &DL, Type *Ty) {
if (Ty->isPointerTy())
return DL.getIntPtrType(Ty);
// It is possible that char's or short's overflow when we ask for the loop's
// trip count, work around this by changing the type size.
if (Ty->getScalarSizeInBits() < 32)
return Type::getInt32Ty(Ty->getContext());
return Ty;
}
static Type* getWiderType(const DataLayout &DL, Type *Ty0, Type *Ty1) {
Ty0 = convertPointerToIntegerType(DL, Ty0);
Ty1 = convertPointerToIntegerType(DL, Ty1);
if (Ty0->getScalarSizeInBits() > Ty1->getScalarSizeInBits())
return Ty0;
return Ty1;
}
/// \brief Check that the instruction has outside loop users and is not an
/// identified reduction variable.
static bool hasOutsideLoopUser(const Loop *TheLoop, Instruction *Inst,
SmallPtrSetImpl<Value *> &Reductions) {
// Reduction instructions are allowed to have exit users. All other
// instructions must not have external users.
if (!Reductions.count(Inst))
//Check that all of the users of the loop are inside the BB.
for (User *U : Inst->users()) {
Instruction *UI = cast<Instruction>(U);
// This user may be a reduction exit value.
if (!TheLoop->contains(UI)) {
DEBUG(dbgs() << "LV: Found an outside user for : " << *UI << '\n');
return true;
}
}
return false;
}
bool LoopVectorizationLegality::canVectorizeInstrs() {
BasicBlock *PreHeader = TheLoop->getLoopPreheader();
BasicBlock *Header = TheLoop->getHeader();
// Look for the attribute signaling the absence of NaNs.
Function &F = *Header->getParent();
const DataLayout &DL = F.getParent()->getDataLayout();
if (F.hasFnAttribute("no-nans-fp-math"))
HasFunNoNaNAttr =
F.getFnAttribute("no-nans-fp-math").getValueAsString() == "true";
// For each block in the loop.
for (Loop::block_iterator bb = TheLoop->block_begin(),
be = TheLoop->block_end(); bb != be; ++bb) {
// Scan the instructions in the block and look for hazards.
for (BasicBlock::iterator it = (*bb)->begin(), e = (*bb)->end(); it != e;
++it) {
if (PHINode *Phi = dyn_cast<PHINode>(it)) {
Type *PhiTy = Phi->getType();
// Check that this PHI type is allowed.
if (!PhiTy->isIntegerTy() &&
!PhiTy->isFloatingPointTy() &&
!PhiTy->isPointerTy()) {
emitAnalysis(VectorizationReport(it)
<< "loop control flow is not understood by vectorizer");
DEBUG(dbgs() << "LV: Found an non-int non-pointer PHI.\n");
return false;
}
// If this PHINode is not in the header block, then we know that we
// can convert it to select during if-conversion. No need to check if
// the PHIs in this block are induction or reduction variables.
if (*bb != Header) {
// Check that this instruction has no outside users or is an
// identified reduction value with an outside user.
if (!hasOutsideLoopUser(TheLoop, it, AllowedExit))
continue;
emitAnalysis(VectorizationReport(it) <<
"value could not be identified as "
"an induction or reduction variable");
return false;
}
// We only allow if-converted PHIs with exactly two incoming values.
if (Phi->getNumIncomingValues() != 2) {
emitAnalysis(VectorizationReport(it)
<< "control flow not understood by vectorizer");
DEBUG(dbgs() << "LV: Found an invalid PHI.\n");
return false;
}
// This is the value coming from the preheader.
Value *StartValue = Phi->getIncomingValueForBlock(PreHeader);
ConstantInt *StepValue = nullptr;
// Check if this is an induction variable.
InductionKind IK = isInductionVariable(Phi, StepValue);
if (IK_NoInduction != IK) {
// Get the widest type.
if (!WidestIndTy)
WidestIndTy = convertPointerToIntegerType(DL, PhiTy);
else
WidestIndTy = getWiderType(DL, PhiTy, WidestIndTy);
// Int inductions are special because we only allow one IV.
if (IK == IK_IntInduction && StepValue->isOne()) {
// Use the phi node with the widest type as induction. Use the last
// one if there are multiple (no good reason for doing this other
// than it is expedient).
if (!Induction || PhiTy == WidestIndTy)
Induction = Phi;
}
DEBUG(dbgs() << "LV: Found an induction variable.\n");
Inductions[Phi] = InductionInfo(StartValue, IK, StepValue);
// Until we explicitly handle the case of an induction variable with
// an outside loop user we have to give up vectorizing this loop.
if (hasOutsideLoopUser(TheLoop, it, AllowedExit)) {
emitAnalysis(VectorizationReport(it) <<
"use of induction value outside of the "
"loop is not handled by vectorizer");
return false;
}
continue;
}
if (RecurrenceDescriptor::isReductionPHI(Phi, TheLoop,
Reductions[Phi])) {
AllowedExit.insert(Reductions[Phi].getLoopExitInstr());
continue;
}
emitAnalysis(VectorizationReport(it) <<
"value that could not be identified as "
"reduction is used outside the loop");
DEBUG(dbgs() << "LV: Found an unidentified PHI."<< *Phi <<"\n");
return false;
}// end of PHI handling
// We handle calls that:
// * Are debug info intrinsics.
// * Have a mapping to an IR intrinsic.
// * Have a vector version available.
CallInst *CI = dyn_cast<CallInst>(it);
if (CI && !getIntrinsicIDForCall(CI, TLI) && !isa<DbgInfoIntrinsic>(CI) &&
!(CI->getCalledFunction() && TLI &&
TLI->isFunctionVectorizable(CI->getCalledFunction()->getName()))) {
emitAnalysis(VectorizationReport(it) <<
"call instruction cannot be vectorized");
DEBUG(dbgs() << "LV: Found a non-intrinsic, non-libfunc callsite.\n");
return false;
}
// Intrinsics such as powi,cttz and ctlz are legal to vectorize if the
// second argument is the same (i.e. loop invariant)
if (CI &&
hasVectorInstrinsicScalarOpd(getIntrinsicIDForCall(CI, TLI), 1)) {
if (!SE->isLoopInvariant(SE->getSCEV(CI->getOperand(1)), TheLoop)) {
emitAnalysis(VectorizationReport(it)
<< "intrinsic instruction cannot be vectorized");
DEBUG(dbgs() << "LV: Found unvectorizable intrinsic " << *CI << "\n");
return false;
}
}
// Check that the instruction return type is vectorizable.
// Also, we can't vectorize extractelement instructions.
if ((!VectorType::isValidElementType(it->getType()) &&
!it->getType()->isVoidTy()) || isa<ExtractElementInst>(it)) {
emitAnalysis(VectorizationReport(it)
<< "instruction return type cannot be vectorized");
DEBUG(dbgs() << "LV: Found unvectorizable type.\n");
return false;
}
// Check that the stored type is vectorizable.
if (StoreInst *ST = dyn_cast<StoreInst>(it)) {
Type *T = ST->getValueOperand()->getType();
if (!VectorType::isValidElementType(T)) {
emitAnalysis(VectorizationReport(ST) <<
"store instruction cannot be vectorized");
return false;
}
if (EnableMemAccessVersioning)
collectStridedAccess(ST);
}
if (EnableMemAccessVersioning)
if (LoadInst *LI = dyn_cast<LoadInst>(it))
collectStridedAccess(LI);
// Reduction instructions are allowed to have exit users.
// All other instructions must not have external users.
if (hasOutsideLoopUser(TheLoop, it, AllowedExit)) {
emitAnalysis(VectorizationReport(it) <<
"value cannot be used outside the loop");
return false;
}
} // next instr.
}
if (!Induction) {
DEBUG(dbgs() << "LV: Did not find one integer induction var.\n");
if (Inductions.empty()) {
emitAnalysis(VectorizationReport()
<< "loop induction variable could not be identified");
return false;
}
}
return true;
}
void LoopVectorizationLegality::collectStridedAccess(Value *MemAccess) {
Value *Ptr = nullptr;
if (LoadInst *LI = dyn_cast<LoadInst>(MemAccess))
Ptr = LI->getPointerOperand();
else if (StoreInst *SI = dyn_cast<StoreInst>(MemAccess))
Ptr = SI->getPointerOperand();
else
return;
Value *Stride = getStrideFromPointer(Ptr, SE, TheLoop);
if (!Stride)
return;
DEBUG(dbgs() << "LV: Found a strided access that we can version");
DEBUG(dbgs() << " Ptr: " << *Ptr << " Stride: " << *Stride << "\n");
Strides[Ptr] = Stride;
StrideSet.insert(Stride);
}
void LoopVectorizationLegality::collectLoopUniforms() {
// We now know that the loop is vectorizable!
// Collect variables that will remain uniform after vectorization.
std::vector<Value*> Worklist;
BasicBlock *Latch = TheLoop->getLoopLatch();
// Start with the conditional branch and walk up the block.
Worklist.push_back(Latch->getTerminator()->getOperand(0));
// Also add all consecutive pointer values; these values will be uniform
// after vectorization (and subsequent cleanup) and, until revectorization is
// supported, all dependencies must also be uniform.
for (Loop::block_iterator B = TheLoop->block_begin(),
BE = TheLoop->block_end(); B != BE; ++B)
for (BasicBlock::iterator I = (*B)->begin(), IE = (*B)->end();
I != IE; ++I)
if (I->getType()->isPointerTy() && isConsecutivePtr(I))
Worklist.insert(Worklist.end(), I->op_begin(), I->op_end());
while (!Worklist.empty()) {
Instruction *I = dyn_cast<Instruction>(Worklist.back());
Worklist.pop_back();
// Look at instructions inside this loop.
// Stop when reaching PHI nodes.
// TODO: we need to follow values all over the loop, not only in this block.
if (!I || !TheLoop->contains(I) || isa<PHINode>(I))
continue;
// This is a known uniform.
Uniforms.insert(I);
// Insert all operands.
Worklist.insert(Worklist.end(), I->op_begin(), I->op_end());
}
}
bool LoopVectorizationLegality::canVectorizeMemory() {
LAI = &LAA->getInfo(TheLoop, Strides);
auto &OptionalReport = LAI->getReport();
if (OptionalReport)
emitAnalysis(VectorizationReport(*OptionalReport));
if (!LAI->canVectorizeMemory())
return false;
if (LAI->hasStoreToLoopInvariantAddress()) {
emitAnalysis(
VectorizationReport()
<< "write to a loop invariant address could not be vectorized");
DEBUG(dbgs() << "LV: We don't allow storing to uniform addresses\n");
return false;
}
if (LAI->getNumRuntimePointerChecks() >
VectorizerParams::RuntimeMemoryCheckThreshold) {
emitAnalysis(VectorizationReport()
<< LAI->getNumRuntimePointerChecks() << " exceeds limit of "
<< VectorizerParams::RuntimeMemoryCheckThreshold
<< " dependent memory operations checked at runtime");
DEBUG(dbgs() << "LV: Too many memory checks needed.\n");
return false;
}
return true;
}
LoopVectorizationLegality::InductionKind
LoopVectorizationLegality::isInductionVariable(PHINode *Phi,
ConstantInt *&StepValue) {
if (!isInductionPHI(Phi, SE, StepValue))
return IK_NoInduction;
Type *PhiTy = Phi->getType();
// Found an Integer induction variable.
if (PhiTy->isIntegerTy())
return IK_IntInduction;
// Found an Pointer induction variable.
return IK_PtrInduction;
}
bool LoopVectorizationLegality::isInductionVariable(const Value *V) {
Value *In0 = const_cast<Value*>(V);
PHINode *PN = dyn_cast_or_null<PHINode>(In0);
if (!PN)
return false;
return Inductions.count(PN);
}
bool LoopVectorizationLegality::blockNeedsPredication(BasicBlock *BB) {
return LoopAccessInfo::blockNeedsPredication(BB, TheLoop, DT);
}
bool LoopVectorizationLegality::blockCanBePredicated(BasicBlock *BB,
SmallPtrSetImpl<Value *> &SafePtrs) {
for (BasicBlock::iterator it = BB->begin(), e = BB->end(); it != e; ++it) {
// Check that we don't have a constant expression that can trap as operand.
for (Instruction::op_iterator OI = it->op_begin(), OE = it->op_end();
OI != OE; ++OI) {
if (Constant *C = dyn_cast<Constant>(*OI))
if (C->canTrap())
return false;
}
// We might be able to hoist the load.
if (it->mayReadFromMemory()) {
LoadInst *LI = dyn_cast<LoadInst>(it);
if (!LI)
return false;
if (!SafePtrs.count(LI->getPointerOperand())) {
if (isLegalMaskedLoad(LI->getType(), LI->getPointerOperand())) {
MaskedOp.insert(LI);
continue;
}
return false;
}
}
// We don't predicate stores at the moment.
if (it->mayWriteToMemory()) {
StoreInst *SI = dyn_cast<StoreInst>(it);
// We only support predication of stores in basic blocks with one
// predecessor.
if (!SI)
return false;
bool isSafePtr = (SafePtrs.count(SI->getPointerOperand()) != 0);
bool isSinglePredecessor = SI->getParent()->getSinglePredecessor();
if (++NumPredStores > NumberOfStoresToPredicate || !isSafePtr ||
!isSinglePredecessor) {
// Build a masked store if it is legal for the target, otherwise scalarize
// the block.
bool isLegalMaskedOp =
isLegalMaskedStore(SI->getValueOperand()->getType(),
SI->getPointerOperand());
if (isLegalMaskedOp) {
--NumPredStores;
MaskedOp.insert(SI);
continue;
}
return false;
}
}
if (it->mayThrow())
return false;
// The instructions below can trap.
switch (it->getOpcode()) {
default: continue;
case Instruction::UDiv:
case Instruction::SDiv:
case Instruction::URem:
case Instruction::SRem:
return false;
}
}
return true;
}
void InterleavedAccessInfo::collectConstStridedAccesses(
MapVector<Instruction *, StrideDescriptor> &StrideAccesses,
const ValueToValueMap &Strides) {
// Holds load/store instructions in program order.
SmallVector<Instruction *, 16> AccessList;
for (auto *BB : TheLoop->getBlocks()) {
bool IsPred = LoopAccessInfo::blockNeedsPredication(BB, TheLoop, DT);
for (auto &I : *BB) {
if (!isa<LoadInst>(&I) && !isa<StoreInst>(&I))
continue;
// FIXME: Currently we can't handle mixed accesses and predicated accesses
if (IsPred)
return;
AccessList.push_back(&I);
}
}
if (AccessList.empty())
return;
auto &DL = TheLoop->getHeader()->getModule()->getDataLayout();
for (auto I : AccessList) {
LoadInst *LI = dyn_cast<LoadInst>(I);
StoreInst *SI = dyn_cast<StoreInst>(I);
Value *Ptr = LI ? LI->getPointerOperand() : SI->getPointerOperand();
int Stride = isStridedPtr(SE, Ptr, TheLoop, Strides);
// The factor of the corresponding interleave group.
unsigned Factor = std::abs(Stride);
// Ignore the access if the factor is too small or too large.
if (Factor < 2 || Factor > MaxInterleaveGroupFactor)
continue;
const SCEV *Scev = replaceSymbolicStrideSCEV(SE, Strides, Ptr);
PointerType *PtrTy = dyn_cast<PointerType>(Ptr->getType());
unsigned Size = DL.getTypeAllocSize(PtrTy->getElementType());
// An alignment of 0 means target ABI alignment.
unsigned Align = LI ? LI->getAlignment() : SI->getAlignment();
if (!Align)
Align = DL.getABITypeAlignment(PtrTy->getElementType());
StrideAccesses[I] = StrideDescriptor(Stride, Scev, Size, Align);
}
}
// Analyze interleaved accesses and collect them into interleave groups.
//
// Notice that the vectorization on interleaved groups will change instruction
// orders and may break dependences. But the memory dependence check guarantees
// that there is no overlap between two pointers of different strides, element
// sizes or underlying bases.
//
// For pointers sharing the same stride, element size and underlying base, no
// need to worry about Read-After-Write dependences and Write-After-Read
// dependences.
//
// E.g. The RAW dependence: A[i] = a;
// b = A[i];
// This won't exist as it is a store-load forwarding conflict, which has
// already been checked and forbidden in the dependence check.
//
// E.g. The WAR dependence: a = A[i]; // (1)
// A[i] = b; // (2)
// The store group of (2) is always inserted at or below (2), and the load group
// of (1) is always inserted at or above (1). The dependence is safe.
void InterleavedAccessInfo::analyzeInterleaving(
const ValueToValueMap &Strides) {
DEBUG(dbgs() << "LV: Analyzing interleaved accesses...\n");
// Holds all the stride accesses.
MapVector<Instruction *, StrideDescriptor> StrideAccesses;
collectConstStridedAccesses(StrideAccesses, Strides);
if (StrideAccesses.empty())
return;
// Holds all interleaved store groups temporarily.
SmallSetVector<InterleaveGroup *, 4> StoreGroups;
// Search the load-load/write-write pair B-A in bottom-up order and try to
// insert B into the interleave group of A according to 3 rules:
// 1. A and B have the same stride.
// 2. A and B have the same memory object size.
// 3. B belongs to the group according to the distance.
//
// The bottom-up order can avoid breaking the Write-After-Write dependences
// between two pointers of the same base.
// E.g. A[i] = a; (1)
// A[i] = b; (2)
// A[i+1] = c (3)
// We form the group (2)+(3) in front, so (1) has to form groups with accesses
// above (1), which guarantees that (1) is always above (2).
for (auto I = StrideAccesses.rbegin(), E = StrideAccesses.rend(); I != E;
++I) {
Instruction *A = I->first;
StrideDescriptor DesA = I->second;
InterleaveGroup *Group = getInterleaveGroup(A);
if (!Group) {
DEBUG(dbgs() << "LV: Creating an interleave group with:" << *A << '\n');
Group = createInterleaveGroup(A, DesA.Stride, DesA.Align);
}
if (A->mayWriteToMemory())
StoreGroups.insert(Group);
for (auto II = std::next(I); II != E; ++II) {
Instruction *B = II->first;
StrideDescriptor DesB = II->second;
// Ignore if B is already in a group or B is a different memory operation.
if (isInterleaved(B) || A->mayReadFromMemory() != B->mayReadFromMemory())
continue;
// Check the rule 1 and 2.
if (DesB.Stride != DesA.Stride || DesB.Size != DesA.Size)
continue;
// Calculate the distance and prepare for the rule 3.
const SCEVConstant *DistToA =
dyn_cast<SCEVConstant>(SE->getMinusSCEV(DesB.Scev, DesA.Scev));
if (!DistToA)
continue;
int DistanceToA = DistToA->getValue()->getValue().getSExtValue();
// Skip if the distance is not multiple of size as they are not in the
// same group.
if (DistanceToA % static_cast<int>(DesA.Size))
continue;
// The index of B is the index of A plus the related index to A.
int IndexB =
Group->getIndex(A) + DistanceToA / static_cast<int>(DesA.Size);
// Try to insert B into the group.
if (Group->insertMember(B, IndexB, DesB.Align)) {
DEBUG(dbgs() << "LV: Inserted:" << *B << '\n'
<< " into the interleave group with" << *A << '\n');
InterleaveGroupMap[B] = Group;
// Set the first load in program order as the insert position.
if (B->mayReadFromMemory())
Group->setInsertPos(B);
}
} // Iteration on instruction B
} // Iteration on instruction A
// Remove interleaved store groups with gaps.
for (InterleaveGroup *Group : StoreGroups)
if (Group->getNumMembers() != Group->getFactor())
releaseGroup(Group);
}
LoopVectorizationCostModel::VectorizationFactor
LoopVectorizationCostModel::selectVectorizationFactor(bool OptForSize) {
// Width 1 means no vectorize
VectorizationFactor Factor = { 1U, 0U };
if (OptForSize && Legal->getRuntimePointerChecking()->Need) {
emitAnalysis(VectorizationReport() <<
"runtime pointer checks needed. Enable vectorization of this "
"loop with '#pragma clang loop vectorize(enable)' when "
"compiling with -Os");
DEBUG(dbgs() << "LV: Aborting. Runtime ptr check is required in Os.\n");
return Factor;
}
if (!EnableCondStoresVectorization && Legal->getNumPredStores()) {
emitAnalysis(VectorizationReport() <<
"store that is conditionally executed prevents vectorization");
DEBUG(dbgs() << "LV: No vectorization. There are conditional stores.\n");
return Factor;
}
// Find the trip count.
unsigned TC = SE->getSmallConstantTripCount(TheLoop);
DEBUG(dbgs() << "LV: Found trip count: " << TC << '\n');
unsigned WidestType = getWidestType();
unsigned WidestRegister = TTI.getRegisterBitWidth(true);
unsigned MaxSafeDepDist = -1U;
if (Legal->getMaxSafeDepDistBytes() != -1U)
MaxSafeDepDist = Legal->getMaxSafeDepDistBytes() * 8;
WidestRegister = ((WidestRegister < MaxSafeDepDist) ?
WidestRegister : MaxSafeDepDist);
unsigned MaxVectorSize = WidestRegister / WidestType;
DEBUG(dbgs() << "LV: The Widest type: " << WidestType << " bits.\n");
DEBUG(dbgs() << "LV: The Widest register is: "
<< WidestRegister << " bits.\n");
if (MaxVectorSize == 0) {
DEBUG(dbgs() << "LV: The target has no vector registers.\n");
MaxVectorSize = 1;
}
assert(MaxVectorSize <= 64 && "Did not expect to pack so many elements"
" into one vector!");
unsigned VF = MaxVectorSize;
// If we optimize the program for size, avoid creating the tail loop.
if (OptForSize) {
// If we are unable to calculate the trip count then don't try to vectorize.
if (TC < 2) {
emitAnalysis
(VectorizationReport() <<
"unable to calculate the loop count due to complex control flow");
DEBUG(dbgs() << "LV: Aborting. A tail loop is required in Os.\n");
return Factor;
}
// Find the maximum SIMD width that can fit within the trip count.
VF = TC % MaxVectorSize;
if (VF == 0)
VF = MaxVectorSize;
else {
// If the trip count that we found modulo the vectorization factor is not
// zero then we require a tail.
emitAnalysis(VectorizationReport() <<
"cannot optimize for size and vectorize at the "
"same time. Enable vectorization of this loop "
"with '#pragma clang loop vectorize(enable)' "
"when compiling with -Os");
DEBUG(dbgs() << "LV: Aborting. A tail loop is required in Os.\n");
return Factor;
}
}
int UserVF = Hints->getWidth();
if (UserVF != 0) {
assert(isPowerOf2_32(UserVF) && "VF needs to be a power of two");
DEBUG(dbgs() << "LV: Using user VF " << UserVF << ".\n");
Factor.Width = UserVF;
return Factor;
}
float Cost = expectedCost(1);
#ifndef NDEBUG
const float ScalarCost = Cost;
#endif /* NDEBUG */
unsigned Width = 1;
DEBUG(dbgs() << "LV: Scalar loop costs: " << (int)ScalarCost << ".\n");
bool ForceVectorization = Hints->getForce() == LoopVectorizeHints::FK_Enabled;
// Ignore scalar width, because the user explicitly wants vectorization.
if (ForceVectorization && VF > 1) {
Width = 2;
Cost = expectedCost(Width) / (float)Width;
}
for (unsigned i=2; i <= VF; i*=2) {
// Notice that the vector loop needs to be executed less times, so
// we need to divide the cost of the vector loops by the width of
// the vector elements.
float VectorCost = expectedCost(i) / (float)i;
DEBUG(dbgs() << "LV: Vector loop of width " << i << " costs: " <<
(int)VectorCost << ".\n");
if (VectorCost < Cost) {
Cost = VectorCost;
Width = i;
}
}
DEBUG(if (ForceVectorization && Width > 1 && Cost >= ScalarCost) dbgs()
<< "LV: Vectorization seems to be not beneficial, "
<< "but was forced by a user.\n");
DEBUG(dbgs() << "LV: Selecting VF: "<< Width << ".\n");
Factor.Width = Width;
Factor.Cost = Width * Cost;
return Factor;
}
unsigned LoopVectorizationCostModel::getWidestType() {
unsigned MaxWidth = 8;
const DataLayout &DL = TheFunction->getParent()->getDataLayout();
// For each block.
for (Loop::block_iterator bb = TheLoop->block_begin(),
be = TheLoop->block_end(); bb != be; ++bb) {
BasicBlock *BB = *bb;
// For each instruction in the loop.
for (BasicBlock::iterator it = BB->begin(), e = BB->end(); it != e; ++it) {
Type *T = it->getType();
// Ignore ephemeral values.
if (EphValues.count(it))
continue;
// Only examine Loads, Stores and PHINodes.
if (!isa<LoadInst>(it) && !isa<StoreInst>(it) && !isa<PHINode>(it))
continue;
// Examine PHI nodes that are reduction variables.
if (PHINode *PN = dyn_cast<PHINode>(it))
if (!Legal->getReductionVars()->count(PN))
continue;
// Examine the stored values.
if (StoreInst *ST = dyn_cast<StoreInst>(it))
T = ST->getValueOperand()->getType();
// Ignore loaded pointer types and stored pointer types that are not
// consecutive. However, we do want to take consecutive stores/loads of
// pointer vectors into account.
if (T->isPointerTy() && !isConsecutiveLoadOrStore(it))
continue;
MaxWidth = std::max(MaxWidth,
(unsigned)DL.getTypeSizeInBits(T->getScalarType()));
}
}
return MaxWidth;
}
unsigned LoopVectorizationCostModel::selectInterleaveCount(bool OptForSize,
unsigned VF,
unsigned LoopCost) {
// -- The interleave heuristics --
// We interleave the loop in order to expose ILP and reduce the loop overhead.
// There are many micro-architectural considerations that we can't predict
// at this level. For example, frontend pressure (on decode or fetch) due to
// code size, or the number and capabilities of the execution ports.
//
// We use the following heuristics to select the interleave count:
// 1. If the code has reductions, then we interleave to break the cross
// iteration dependency.
// 2. If the loop is really small, then we interleave to reduce the loop
// overhead.
// 3. We don't interleave if we think that we will spill registers to memory
// due to the increased register pressure.
// Use the user preference, unless 'auto' is selected.
int UserUF = Hints->getInterleave();
if (UserUF != 0)
return UserUF;
// When we optimize for size, we don't interleave.
if (OptForSize)
return 1;
// We used the distance for the interleave count.
if (Legal->getMaxSafeDepDistBytes() != -1U)
return 1;
// Do not interleave loops with a relatively small trip count.
unsigned TC = SE->getSmallConstantTripCount(TheLoop);
if (TC > 1 && TC < TinyTripCountInterleaveThreshold)
return 1;
unsigned TargetNumRegisters = TTI.getNumberOfRegisters(VF > 1);
DEBUG(dbgs() << "LV: The target has " << TargetNumRegisters <<
" registers\n");
if (VF == 1) {
if (ForceTargetNumScalarRegs.getNumOccurrences() > 0)
TargetNumRegisters = ForceTargetNumScalarRegs;
} else {
if (ForceTargetNumVectorRegs.getNumOccurrences() > 0)
TargetNumRegisters = ForceTargetNumVectorRegs;
}
LoopVectorizationCostModel::RegisterUsage R = calculateRegisterUsage();
// We divide by these constants so assume that we have at least one
// instruction that uses at least one register.
R.MaxLocalUsers = std::max(R.MaxLocalUsers, 1U);
R.NumInstructions = std::max(R.NumInstructions, 1U);
// We calculate the interleave count using the following formula.
// Subtract the number of loop invariants from the number of available
// registers. These registers are used by all of the interleaved instances.
// Next, divide the remaining registers by the number of registers that is
// required by the loop, in order to estimate how many parallel instances
// fit without causing spills. All of this is rounded down if necessary to be
// a power of two. We want power of two interleave count to simplify any
// addressing operations or alignment considerations.
unsigned IC = PowerOf2Floor((TargetNumRegisters - R.LoopInvariantRegs) /
R.MaxLocalUsers);
// Don't count the induction variable as interleaved.
if (EnableIndVarRegisterHeur)
IC = PowerOf2Floor((TargetNumRegisters - R.LoopInvariantRegs - 1) /
std::max(1U, (R.MaxLocalUsers - 1)));
// Clamp the interleave ranges to reasonable counts.
unsigned MaxInterleaveCount = TTI.getMaxInterleaveFactor(VF);
// Check if the user has overridden the max.
if (VF == 1) {
if (ForceTargetMaxScalarInterleaveFactor.getNumOccurrences() > 0)
MaxInterleaveCount = ForceTargetMaxScalarInterleaveFactor;
} else {
if (ForceTargetMaxVectorInterleaveFactor.getNumOccurrences() > 0)
MaxInterleaveCount = ForceTargetMaxVectorInterleaveFactor;
}
// If we did not calculate the cost for VF (because the user selected the VF)
// then we calculate the cost of VF here.
if (LoopCost == 0)
LoopCost = expectedCost(VF);
// Clamp the calculated IC to be between the 1 and the max interleave count
// that the target allows.
if (IC > MaxInterleaveCount)
IC = MaxInterleaveCount;
else if (IC < 1)
IC = 1;
// Interleave if we vectorized this loop and there is a reduction that could
// benefit from interleaving.
if (VF > 1 && Legal->getReductionVars()->size()) {
DEBUG(dbgs() << "LV: Interleaving because of reductions.\n");
return IC;
}
// Note that if we've already vectorized the loop we will have done the
// runtime check and so interleaving won't require further checks.
bool InterleavingRequiresRuntimePointerCheck =
(VF == 1 && Legal->getRuntimePointerChecking()->Need);
// We want to interleave small loops in order to reduce the loop overhead and
// potentially expose ILP opportunities.
DEBUG(dbgs() << "LV: Loop cost is " << LoopCost << '\n');
if (!InterleavingRequiresRuntimePointerCheck && LoopCost < SmallLoopCost) {
// We assume that the cost overhead is 1 and we use the cost model
// to estimate the cost of the loop and interleave until the cost of the
// loop overhead is about 5% of the cost of the loop.
unsigned SmallIC =
std::min(IC, (unsigned)PowerOf2Floor(SmallLoopCost / LoopCost));
// Interleave until store/load ports (estimated by max interleave count) are
// saturated.
unsigned NumStores = Legal->getNumStores();
unsigned NumLoads = Legal->getNumLoads();
unsigned StoresIC = IC / (NumStores ? NumStores : 1);
unsigned LoadsIC = IC / (NumLoads ? NumLoads : 1);
// If we have a scalar reduction (vector reductions are already dealt with
// by this point), we can increase the critical path length if the loop
// we're interleaving is inside another loop. Limit, by default to 2, so the
// critical path only gets increased by one reduction operation.
if (Legal->getReductionVars()->size() &&
TheLoop->getLoopDepth() > 1) {
unsigned F = static_cast<unsigned>(MaxNestedScalarReductionIC);
SmallIC = std::min(SmallIC, F);
StoresIC = std::min(StoresIC, F);
LoadsIC = std::min(LoadsIC, F);
}
if (EnableLoadStoreRuntimeInterleave &&
std::max(StoresIC, LoadsIC) > SmallIC) {
DEBUG(dbgs() << "LV: Interleaving to saturate store or load ports.\n");
return std::max(StoresIC, LoadsIC);
}
DEBUG(dbgs() << "LV: Interleaving to reduce branch cost.\n");
return SmallIC;
}
// Interleave if this is a large loop (small loops are already dealt with by
// this
// point) that could benefit from interleaving.
bool HasReductions = (Legal->getReductionVars()->size() > 0);
if (TTI.enableAggressiveInterleaving(HasReductions)) {
DEBUG(dbgs() << "LV: Interleaving to expose ILP.\n");
return IC;
}
DEBUG(dbgs() << "LV: Not Interleaving.\n");
return 1;
}
LoopVectorizationCostModel::RegisterUsage
LoopVectorizationCostModel::calculateRegisterUsage() {
// This function calculates the register usage by measuring the highest number
// of values that are alive at a single location. Obviously, this is a very
// rough estimation. We scan the loop in a topological order in order and
// assign a number to each instruction. We use RPO to ensure that defs are
// met before their users. We assume that each instruction that has in-loop
// users starts an interval. We record every time that an in-loop value is
// used, so we have a list of the first and last occurrences of each
// instruction. Next, we transpose this data structure into a multi map that
// holds the list of intervals that *end* at a specific location. This multi
// map allows us to perform a linear search. We scan the instructions linearly
// and record each time that a new interval starts, by placing it in a set.
// If we find this value in the multi-map then we remove it from the set.
// The max register usage is the maximum size of the set.
// We also search for instructions that are defined outside the loop, but are
// used inside the loop. We need this number separately from the max-interval
// usage number because when we unroll, loop-invariant values do not take
// more register.
LoopBlocksDFS DFS(TheLoop);
DFS.perform(LI);
RegisterUsage R;
R.NumInstructions = 0;
// Each 'key' in the map opens a new interval. The values
// of the map are the index of the 'last seen' usage of the
// instruction that is the key.
typedef DenseMap<Instruction*, unsigned> IntervalMap;
// Maps instruction to its index.
DenseMap<unsigned, Instruction*> IdxToInstr;
// Marks the end of each interval.
IntervalMap EndPoint;
// Saves the list of instruction indices that are used in the loop.
SmallSet<Instruction*, 8> Ends;
// Saves the list of values that are used in the loop but are
// defined outside the loop, such as arguments and constants.
SmallPtrSet<Value*, 8> LoopInvariants;
unsigned Index = 0;
for (LoopBlocksDFS::RPOIterator bb = DFS.beginRPO(),
be = DFS.endRPO(); bb != be; ++bb) {
R.NumInstructions += (*bb)->size();
for (BasicBlock::iterator it = (*bb)->begin(), e = (*bb)->end(); it != e;
++it) {
Instruction *I = it;
IdxToInstr[Index++] = I;
// Save the end location of each USE.
for (unsigned i = 0; i < I->getNumOperands(); ++i) {
Value *U = I->getOperand(i);
Instruction *Instr = dyn_cast<Instruction>(U);
// Ignore non-instruction values such as arguments, constants, etc.
if (!Instr) continue;
// If this instruction is outside the loop then record it and continue.
if (!TheLoop->contains(Instr)) {
LoopInvariants.insert(Instr);
continue;
}
// Overwrite previous end points.
EndPoint[Instr] = Index;
Ends.insert(Instr);
}
}
}
// Saves the list of intervals that end with the index in 'key'.
typedef SmallVector<Instruction*, 2> InstrList;
DenseMap<unsigned, InstrList> TransposeEnds;
// Transpose the EndPoints to a list of values that end at each index.
for (IntervalMap::iterator it = EndPoint.begin(), e = EndPoint.end();
it != e; ++it)
TransposeEnds[it->second].push_back(it->first);
SmallSet<Instruction*, 8> OpenIntervals;
unsigned MaxUsage = 0;
DEBUG(dbgs() << "LV(REG): Calculating max register usage:\n");
for (unsigned int i = 0; i < Index; ++i) {
Instruction *I = IdxToInstr[i];
// Ignore instructions that are never used within the loop.
if (!Ends.count(I)) continue;
// Ignore ephemeral values.
if (EphValues.count(I))
continue;
// Remove all of the instructions that end at this location.
InstrList &List = TransposeEnds[i];
for (unsigned int j=0, e = List.size(); j < e; ++j)
OpenIntervals.erase(List[j]);
// Count the number of live interals.
MaxUsage = std::max(MaxUsage, OpenIntervals.size());
DEBUG(dbgs() << "LV(REG): At #" << i << " Interval # " <<
OpenIntervals.size() << '\n');
// Add the current instruction to the list of open intervals.
OpenIntervals.insert(I);
}
unsigned Invariant = LoopInvariants.size();
DEBUG(dbgs() << "LV(REG): Found max usage: " << MaxUsage << '\n');
DEBUG(dbgs() << "LV(REG): Found invariant usage: " << Invariant << '\n');
DEBUG(dbgs() << "LV(REG): LoopSize: " << R.NumInstructions << '\n');
R.LoopInvariantRegs = Invariant;
R.MaxLocalUsers = MaxUsage;
return R;
}
unsigned LoopVectorizationCostModel::expectedCost(unsigned VF) {
unsigned Cost = 0;
// For each block.
for (Loop::block_iterator bb = TheLoop->block_begin(),
be = TheLoop->block_end(); bb != be; ++bb) {
unsigned BlockCost = 0;
BasicBlock *BB = *bb;
// For each instruction in the old loop.
for (BasicBlock::iterator it = BB->begin(), e = BB->end(); it != e; ++it) {
// Skip dbg intrinsics.
if (isa<DbgInfoIntrinsic>(it))
continue;
// Ignore ephemeral values.
if (EphValues.count(it))
continue;
unsigned C = getInstructionCost(it, VF);
// Check if we should override the cost.
if (ForceTargetInstructionCost.getNumOccurrences() > 0)
C = ForceTargetInstructionCost;
BlockCost += C;
DEBUG(dbgs() << "LV: Found an estimated cost of " << C << " for VF " <<
VF << " For instruction: " << *it << '\n');
}
// We assume that if-converted blocks have a 50% chance of being executed.
// When the code is scalar then some of the blocks are avoided due to CF.
// When the code is vectorized we execute all code paths.
if (VF == 1 && Legal->blockNeedsPredication(*bb))
BlockCost /= 2;
Cost += BlockCost;
}
return Cost;
}
/// \brief Check whether the address computation for a non-consecutive memory
/// access looks like an unlikely candidate for being merged into the indexing
/// mode.
///
/// We look for a GEP which has one index that is an induction variable and all
/// other indices are loop invariant. If the stride of this access is also
/// within a small bound we decide that this address computation can likely be
/// merged into the addressing mode.
/// In all other cases, we identify the address computation as complex.
static bool isLikelyComplexAddressComputation(Value *Ptr,
LoopVectorizationLegality *Legal,
ScalarEvolution *SE,
const Loop *TheLoop) {
GetElementPtrInst *Gep = dyn_cast<GetElementPtrInst>(Ptr);
if (!Gep)
return true;
// We are looking for a gep with all loop invariant indices except for one
// which should be an induction variable.
unsigned NumOperands = Gep->getNumOperands();
for (unsigned i = 1; i < NumOperands; ++i) {
Value *Opd = Gep->getOperand(i);
if (!SE->isLoopInvariant(SE->getSCEV(Opd), TheLoop) &&
!Legal->isInductionVariable(Opd))
return true;
}
// Now we know we have a GEP ptr, %inv, %ind, %inv. Make sure that the step
// can likely be merged into the address computation.
unsigned MaxMergeDistance = 64;
const SCEVAddRecExpr *AddRec = dyn_cast<SCEVAddRecExpr>(SE->getSCEV(Ptr));
if (!AddRec)
return true;
// Check the step is constant.
const SCEV *Step = AddRec->getStepRecurrence(*SE);
// Calculate the pointer stride and check if it is consecutive.
const SCEVConstant *C = dyn_cast<SCEVConstant>(Step);
if (!C)
return true;
const APInt &APStepVal = C->getValue()->getValue();
// Huge step value - give up.
if (APStepVal.getBitWidth() > 64)
return true;
int64_t StepVal = APStepVal.getSExtValue();
return StepVal > MaxMergeDistance;
}
static bool isStrideMul(Instruction *I, LoopVectorizationLegality *Legal) {
if (Legal->hasStride(I->getOperand(0)) || Legal->hasStride(I->getOperand(1)))
return true;
return false;
}
unsigned
LoopVectorizationCostModel::getInstructionCost(Instruction *I, unsigned VF) {
// If we know that this instruction will remain uniform, check the cost of
// the scalar version.
if (Legal->isUniformAfterVectorization(I))
VF = 1;
Type *RetTy = I->getType();
Type *VectorTy = ToVectorTy(RetTy, VF);
// TODO: We need to estimate the cost of intrinsic calls.
switch (I->getOpcode()) {
case Instruction::GetElementPtr:
// We mark this instruction as zero-cost because the cost of GEPs in
// vectorized code depends on whether the corresponding memory instruction
// is scalarized or not. Therefore, we handle GEPs with the memory
// instruction cost.
return 0;
case Instruction::Br: {
return TTI.getCFInstrCost(I->getOpcode());
}
case Instruction::PHI:
//TODO: IF-converted IFs become selects.
return 0;
case Instruction::Add:
case Instruction::FAdd:
case Instruction::Sub:
case Instruction::FSub:
case Instruction::Mul:
case Instruction::FMul:
case Instruction::UDiv:
case Instruction::SDiv:
case Instruction::FDiv:
case Instruction::URem:
case Instruction::SRem:
case Instruction::FRem:
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor: {
// Since we will replace the stride by 1 the multiplication should go away.
if (I->getOpcode() == Instruction::Mul && isStrideMul(I, Legal))
return 0;
// Certain instructions can be cheaper to vectorize if they have a constant
// second vector operand. One example of this are shifts on x86.
TargetTransformInfo::OperandValueKind Op1VK =
TargetTransformInfo::OK_AnyValue;
TargetTransformInfo::OperandValueKind Op2VK =
TargetTransformInfo::OK_AnyValue;
TargetTransformInfo::OperandValueProperties Op1VP =
TargetTransformInfo::OP_None;
TargetTransformInfo::OperandValueProperties Op2VP =
TargetTransformInfo::OP_None;
Value *Op2 = I->getOperand(1);
// Check for a splat of a constant or for a non uniform vector of constants.
if (isa<ConstantInt>(Op2)) {
ConstantInt *CInt = cast<ConstantInt>(Op2);
if (CInt && CInt->getValue().isPowerOf2())
Op2VP = TargetTransformInfo::OP_PowerOf2;
Op2VK = TargetTransformInfo::OK_UniformConstantValue;
} else if (isa<ConstantVector>(Op2) || isa<ConstantDataVector>(Op2)) {
Op2VK = TargetTransformInfo::OK_NonUniformConstantValue;
Constant *SplatValue = cast<Constant>(Op2)->getSplatValue();
if (SplatValue) {
ConstantInt *CInt = dyn_cast<ConstantInt>(SplatValue);
if (CInt && CInt->getValue().isPowerOf2())
Op2VP = TargetTransformInfo::OP_PowerOf2;
Op2VK = TargetTransformInfo::OK_UniformConstantValue;
}
}
return TTI.getArithmeticInstrCost(I->getOpcode(), VectorTy, Op1VK, Op2VK,
Op1VP, Op2VP);
}
case Instruction::Select: {
SelectInst *SI = cast<SelectInst>(I);
const SCEV *CondSCEV = SE->getSCEV(SI->getCondition());
bool ScalarCond = (SE->isLoopInvariant(CondSCEV, TheLoop));
Type *CondTy = SI->getCondition()->getType();
if (!ScalarCond)
CondTy = VectorType::get(CondTy, VF);
return TTI.getCmpSelInstrCost(I->getOpcode(), VectorTy, CondTy);
}
case Instruction::ICmp:
case Instruction::FCmp: {
Type *ValTy = I->getOperand(0)->getType();
VectorTy = ToVectorTy(ValTy, VF);
return TTI.getCmpSelInstrCost(I->getOpcode(), VectorTy);
}
case Instruction::Store:
case Instruction::Load: {
StoreInst *SI = dyn_cast<StoreInst>(I);
LoadInst *LI = dyn_cast<LoadInst>(I);
Type *ValTy = (SI ? SI->getValueOperand()->getType() :
LI->getType());
VectorTy = ToVectorTy(ValTy, VF);
unsigned Alignment = SI ? SI->getAlignment() : LI->getAlignment();
unsigned AS = SI ? SI->getPointerAddressSpace() :
LI->getPointerAddressSpace();
Value *Ptr = SI ? SI->getPointerOperand() : LI->getPointerOperand();
// We add the cost of address computation here instead of with the gep
// instruction because only here we know whether the operation is
// scalarized.
if (VF == 1)
return TTI.getAddressComputationCost(VectorTy) +
TTI.getMemoryOpCost(I->getOpcode(), VectorTy, Alignment, AS);
// For an interleaved access, calculate the total cost of the whole
// interleave group.
if (Legal->isAccessInterleaved(I)) {
auto Group = Legal->getInterleavedAccessGroup(I);
assert(Group && "Fail to get an interleaved access group.");
// Only calculate the cost once at the insert position.
if (Group->getInsertPos() != I)
return 0;
unsigned InterleaveFactor = Group->getFactor();
Type *WideVecTy =
VectorType::get(VectorTy->getVectorElementType(),
VectorTy->getVectorNumElements() * InterleaveFactor);
// Holds the indices of existing members in an interleaved load group.
// An interleaved store group doesn't need this as it dones't allow gaps.
SmallVector<unsigned, 4> Indices;
if (LI) {
for (unsigned i = 0; i < InterleaveFactor; i++)
if (Group->getMember(i))
Indices.push_back(i);
}
// Calculate the cost of the whole interleaved group.
unsigned Cost = TTI.getInterleavedMemoryOpCost(
I->getOpcode(), WideVecTy, Group->getFactor(), Indices,
Group->getAlignment(), AS);
if (Group->isReverse())
Cost +=
Group->getNumMembers() *
TTI.getShuffleCost(TargetTransformInfo::SK_Reverse, VectorTy, 0);
// FIXME: The interleaved load group with a huge gap could be even more
// expensive than scalar operations. Then we could ignore such group and
// use scalar operations instead.
return Cost;
}
// Scalarized loads/stores.
int ConsecutiveStride = Legal->isConsecutivePtr(Ptr);
bool Reverse = ConsecutiveStride < 0;
const DataLayout &DL = I->getModule()->getDataLayout();
unsigned ScalarAllocatedSize = DL.getTypeAllocSize(ValTy);
unsigned VectorElementSize = DL.getTypeStoreSize(VectorTy) / VF;
if (!ConsecutiveStride || ScalarAllocatedSize != VectorElementSize) {
bool IsComplexComputation =
isLikelyComplexAddressComputation(Ptr, Legal, SE, TheLoop);
unsigned Cost = 0;
// The cost of extracting from the value vector and pointer vector.
Type *PtrTy = ToVectorTy(Ptr->getType(), VF);
for (unsigned i = 0; i < VF; ++i) {
// The cost of extracting the pointer operand.
Cost += TTI.getVectorInstrCost(Instruction::ExtractElement, PtrTy, i);
// In case of STORE, the cost of ExtractElement from the vector.
// In case of LOAD, the cost of InsertElement into the returned
// vector.
Cost += TTI.getVectorInstrCost(SI ? Instruction::ExtractElement :
Instruction::InsertElement,
VectorTy, i);
}
// The cost of the scalar loads/stores.
Cost += VF * TTI.getAddressComputationCost(PtrTy, IsComplexComputation);
Cost += VF * TTI.getMemoryOpCost(I->getOpcode(), ValTy->getScalarType(),
Alignment, AS);
return Cost;
}
// Wide load/stores.
unsigned Cost = TTI.getAddressComputationCost(VectorTy);
if (Legal->isMaskRequired(I))
Cost += TTI.getMaskedMemoryOpCost(I->getOpcode(), VectorTy, Alignment,
AS);
else
Cost += TTI.getMemoryOpCost(I->getOpcode(), VectorTy, Alignment, AS);
if (Reverse)
Cost += TTI.getShuffleCost(TargetTransformInfo::SK_Reverse,
VectorTy, 0);
return Cost;
}
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::FPToUI:
case Instruction::FPToSI:
case Instruction::FPExt:
case Instruction::PtrToInt:
case Instruction::IntToPtr:
case Instruction::SIToFP:
case Instruction::UIToFP:
case Instruction::Trunc:
case Instruction::FPTrunc:
case Instruction::BitCast: {
// We optimize the truncation of induction variable.
// The cost of these is the same as the scalar operation.
if (I->getOpcode() == Instruction::Trunc &&
Legal->isInductionVariable(I->getOperand(0)))
return TTI.getCastInstrCost(I->getOpcode(), I->getType(),
I->getOperand(0)->getType());
Type *SrcVecTy = ToVectorTy(I->getOperand(0)->getType(), VF);
return TTI.getCastInstrCost(I->getOpcode(), VectorTy, SrcVecTy);
}
case Instruction::Call: {
bool NeedToScalarize;
CallInst *CI = cast<CallInst>(I);
unsigned CallCost = getVectorCallCost(CI, VF, TTI, TLI, NeedToScalarize);
if (getIntrinsicIDForCall(CI, TLI))
return std::min(CallCost, getVectorIntrinsicCost(CI, VF, TTI, TLI));
return CallCost;
}
default: {
// We are scalarizing the instruction. Return the cost of the scalar
// instruction, plus the cost of insert and extract into vector
// elements, times the vector width.
unsigned Cost = 0;
if (!RetTy->isVoidTy() && VF != 1) {
unsigned InsCost = TTI.getVectorInstrCost(Instruction::InsertElement,
VectorTy);
unsigned ExtCost = TTI.getVectorInstrCost(Instruction::ExtractElement,
VectorTy);
// The cost of inserting the results plus extracting each one of the
// operands.
Cost += VF * (InsCost + ExtCost * I->getNumOperands());
}
// The cost of executing VF copies of the scalar instruction. This opcode
// is unknown. Assume that it is the same as 'mul'.
Cost += VF * TTI.getArithmeticInstrCost(Instruction::Mul, VectorTy);
return Cost;
}
}// end of switch.
}
char LoopVectorize::ID = 0;
static const char lv_name[] = "Loop Vectorization";
INITIALIZE_PASS_BEGIN(LoopVectorize, LV_NAME, lv_name, false, false)
INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)
INITIALIZE_AG_DEPENDENCY(AliasAnalysis)
INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)
INITIALIZE_PASS_DEPENDENCY(BlockFrequencyInfo)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_DEPENDENCY(ScalarEvolution)
INITIALIZE_PASS_DEPENDENCY(LCSSA)
INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopSimplify)
INITIALIZE_PASS_DEPENDENCY(LoopAccessAnalysis)
INITIALIZE_PASS_END(LoopVectorize, LV_NAME, lv_name, false, false)
namespace llvm {
Pass *createLoopVectorizePass(bool NoUnrolling, bool AlwaysVectorize) {
return new LoopVectorize(NoUnrolling, AlwaysVectorize);
}
}
bool LoopVectorizationCostModel::isConsecutiveLoadOrStore(Instruction *Inst) {
// Check for a store.
if (StoreInst *ST = dyn_cast<StoreInst>(Inst))
return Legal->isConsecutivePtr(ST->getPointerOperand()) != 0;
// Check for a load.
if (LoadInst *LI = dyn_cast<LoadInst>(Inst))
return Legal->isConsecutivePtr(LI->getPointerOperand()) != 0;
return false;
}
void InnerLoopUnroller::scalarizeInstruction(Instruction *Instr,
bool IfPredicateStore) {
assert(!Instr->getType()->isAggregateType() && "Can't handle vectors");
// Holds vector parameters or scalars, in case of uniform vals.
SmallVector<VectorParts, 4> Params;
setDebugLocFromInst(Builder, Instr);
// Find all of the vectorized parameters.
for (unsigned op = 0, e = Instr->getNumOperands(); op != e; ++op) {
Value *SrcOp = Instr->getOperand(op);
// If we are accessing the old induction variable, use the new one.
if (SrcOp == OldInduction) {
Params.push_back(getVectorValue(SrcOp));
continue;
}
// Try using previously calculated values.
Instruction *SrcInst = dyn_cast<Instruction>(SrcOp);
// If the src is an instruction that appeared earlier in the basic block
// then it should already be vectorized.
if (SrcInst && OrigLoop->contains(SrcInst)) {
assert(WidenMap.has(SrcInst) && "Source operand is unavailable");
// The parameter is a vector value from earlier.
Params.push_back(WidenMap.get(SrcInst));
} else {
// The parameter is a scalar from outside the loop. Maybe even a constant.
VectorParts Scalars;
Scalars.append(UF, SrcOp);
Params.push_back(Scalars);
}
}
assert(Params.size() == Instr->getNumOperands() &&
"Invalid number of operands");
// Does this instruction return a value ?
bool IsVoidRetTy = Instr->getType()->isVoidTy();
Value *UndefVec = IsVoidRetTy ? nullptr :
UndefValue::get(Instr->getType());
// Create a new entry in the WidenMap and initialize it to Undef or Null.
VectorParts &VecResults = WidenMap.splat(Instr, UndefVec);
Instruction *InsertPt = Builder.GetInsertPoint();
BasicBlock *IfBlock = Builder.GetInsertBlock();
BasicBlock *CondBlock = nullptr;
VectorParts Cond;
Loop *VectorLp = nullptr;
if (IfPredicateStore) {
assert(Instr->getParent()->getSinglePredecessor() &&
"Only support single predecessor blocks");
Cond = createEdgeMask(Instr->getParent()->getSinglePredecessor(),
Instr->getParent());
VectorLp = LI->getLoopFor(IfBlock);
assert(VectorLp && "Must have a loop for this block");
}
// For each vector unroll 'part':
for (unsigned Part = 0; Part < UF; ++Part) {
// For each scalar that we create:
// Start an "if (pred) a[i] = ..." block.
Value *Cmp = nullptr;
if (IfPredicateStore) {
if (Cond[Part]->getType()->isVectorTy())
Cond[Part] =
Builder.CreateExtractElement(Cond[Part], Builder.getInt32(0));
Cmp = Builder.CreateICmp(ICmpInst::ICMP_EQ, Cond[Part],
ConstantInt::get(Cond[Part]->getType(), 1));
CondBlock = IfBlock->splitBasicBlock(InsertPt, "cond.store");
LoopVectorBody.push_back(CondBlock);
VectorLp->addBasicBlockToLoop(CondBlock, *LI);
// Update Builder with newly created basic block.
Builder.SetInsertPoint(InsertPt);
}
Instruction *Cloned = Instr->clone();
if (!IsVoidRetTy)
Cloned->setName(Instr->getName() + ".cloned");
// Replace the operands of the cloned instructions with extracted scalars.
for (unsigned op = 0, e = Instr->getNumOperands(); op != e; ++op) {
Value *Op = Params[op][Part];
Cloned->setOperand(op, Op);
}
// Place the cloned scalar in the new loop.
Builder.Insert(Cloned);
// If the original scalar returns a value we need to place it in a vector
// so that future users will be able to use it.
if (!IsVoidRetTy)
VecResults[Part] = Cloned;
// End if-block.
if (IfPredicateStore) {
BasicBlock *NewIfBlock = CondBlock->splitBasicBlock(InsertPt, "else");
LoopVectorBody.push_back(NewIfBlock);
VectorLp->addBasicBlockToLoop(NewIfBlock, *LI);
Builder.SetInsertPoint(InsertPt);
ReplaceInstWithInst(IfBlock->getTerminator(),
BranchInst::Create(CondBlock, NewIfBlock, Cmp));
IfBlock = NewIfBlock;
}
}
}
void InnerLoopUnroller::vectorizeMemoryInstruction(Instruction *Instr) {
StoreInst *SI = dyn_cast<StoreInst>(Instr);
bool IfPredicateStore = (SI && Legal->blockNeedsPredication(SI->getParent()));
return scalarizeInstruction(Instr, IfPredicateStore);
}
Value *InnerLoopUnroller::reverseVector(Value *Vec) {
return Vec;
}
Value *InnerLoopUnroller::getBroadcastInstrs(Value *V) {
return V;
}
Value *InnerLoopUnroller::getStepVector(Value *Val, int StartIdx, Value *Step) {
// When unrolling and the VF is 1, we only need to add a simple scalar.
Type *ITy = Val->getType();
assert(!ITy->isVectorTy() && "Val must be a scalar");
Constant *C = ConstantInt::get(ITy, StartIdx);
return Builder.CreateAdd(Val, Builder.CreateMul(C, Step), "induction");
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Vectorize/CMakeLists.txt | set(HLSL_IGNORE_SOURCES BBVectorize.cpp LoopVectorize.cpp SLPVectorizer.cpp)
add_llvm_library(LLVMVectorize
Vectorize.cpp
# BBVectorize.cpp
# LoopVectorize.cpp
# SLPVectorizer.cpp
ADDITIONAL_HEADER_DIRS
${LLVM_MAIN_INCLUDE_DIR}/llvm/Transforms
)
add_dependencies(LLVMVectorize intrinsics_gen)
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Vectorize/LLVMBuild.txt | ;===- ./lib/Transforms/Scalar/LLVMBuild.txt --------------------*- Conf -*--===;
;
; The LLVM Compiler Infrastructure
;
; This file is distributed under the University of Illinois Open Source
; License. See LICENSE.TXT for details.
;
;===------------------------------------------------------------------------===;
;
; This is an LLVMBuild description file for the components in this subdirectory.
;
; For more information on the LLVMBuild system, please see:
;
; http://llvm.org/docs/LLVMBuild.html
;
;===------------------------------------------------------------------------===;
[component_0]
type = Library
name = Vectorize
parent = Transforms
library_name = Vectorize
required_libraries = Analysis Core Support TransformUtils
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Vectorize/SLPVectorizer.cpp | //===- SLPVectorizer.cpp - A bottom up SLP Vectorizer ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// This pass implements the Bottom Up SLP vectorizer. It detects consecutive
// stores that can be put together into vector-stores. Next, it attempts to
// construct vectorizable tree using the use-def chains. If a profitable tree
// was found, the SLP vectorizer performs vectorization on the tree.
//
// The pass is inspired by the work described in the paper:
// "Loop-Aware SLP in GCC" by Ira Rosen, Dorit Nuzman, Ayal Zaks.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Vectorize.h"
#include "llvm/ADT/MapVector.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/PostOrderIterator.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/CodeMetrics.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/ScalarEvolutionExpressions.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/NoFolder.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/Value.h"
#include "llvm/IR/Verifier.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Analysis/VectorUtils.h"
#include <algorithm>
#include <map>
#include <memory>
// //
///////////////////////////////////////////////////////////////////////////////
using namespace llvm;
#define SV_NAME "slp-vectorizer"
#define DEBUG_TYPE "SLP"
STATISTIC(NumVectorInstructions, "Number of vector instructions generated");
static cl::opt<int>
SLPCostThreshold("slp-threshold", cl::init(0), cl::Hidden,
cl::desc("Only vectorize if you gain more than this "
"number "));
static cl::opt<bool>
ShouldVectorizeHor("slp-vectorize-hor", cl::init(false), cl::Hidden,
cl::desc("Attempt to vectorize horizontal reductions"));
static cl::opt<bool> ShouldStartVectorizeHorAtStore(
"slp-vectorize-hor-store", cl::init(false), cl::Hidden,
cl::desc(
"Attempt to vectorize horizontal reductions feeding into a store"));
static cl::opt<int>
MaxVectorRegSizeOption("slp-max-reg-size", cl::init(128), cl::Hidden,
cl::desc("Attempt to vectorize for this register size in bits"));
namespace {
// FIXME: Set this via cl::opt to allow overriding.
static const unsigned MinVecRegSize = 128;
static const unsigned RecursionMaxDepth = 12;
// Limit the number of alias checks. The limit is chosen so that
// it has no negative effect on the llvm benchmarks.
static const unsigned AliasedCheckLimit = 10;
// Another limit for the alias checks: The maximum distance between load/store
// instructions where alias checks are done.
// This limit is useful for very large basic blocks.
static const unsigned MaxMemDepDistance = 160;
/// \brief Predicate for the element types that the SLP vectorizer supports.
///
/// The most important thing to filter here are types which are invalid in LLVM
/// vectors. We also filter target specific types which have absolutely no
/// meaningful vectorization path such as x86_fp80 and ppc_f128. This just
/// avoids spending time checking the cost model and realizing that they will
/// be inevitably scalarized.
static bool isValidElementType(Type *Ty) {
return VectorType::isValidElementType(Ty) && !Ty->isX86_FP80Ty() &&
!Ty->isPPC_FP128Ty();
}
/// \returns the parent basic block if all of the instructions in \p VL
/// are in the same block or null otherwise.
static BasicBlock *getSameBlock(ArrayRef<Value *> VL) {
Instruction *I0 = dyn_cast<Instruction>(VL[0]);
if (!I0)
return nullptr;
BasicBlock *BB = I0->getParent();
for (int i = 1, e = VL.size(); i < e; i++) {
Instruction *I = dyn_cast<Instruction>(VL[i]);
if (!I)
return nullptr;
if (BB != I->getParent())
return nullptr;
}
return BB;
}
/// \returns True if all of the values in \p VL are constants.
static bool allConstant(ArrayRef<Value *> VL) {
for (unsigned i = 0, e = VL.size(); i < e; ++i)
if (!isa<Constant>(VL[i]))
return false;
return true;
}
/// \returns True if all of the values in \p VL are identical.
static bool isSplat(ArrayRef<Value *> VL) {
for (unsigned i = 1, e = VL.size(); i < e; ++i)
if (VL[i] != VL[0])
return false;
return true;
}
///\returns Opcode that can be clubbed with \p Op to create an alternate
/// sequence which can later be merged as a ShuffleVector instruction.
static unsigned getAltOpcode(unsigned Op) {
switch (Op) {
case Instruction::FAdd:
return Instruction::FSub;
case Instruction::FSub:
return Instruction::FAdd;
case Instruction::Add:
return Instruction::Sub;
case Instruction::Sub:
return Instruction::Add;
default:
return 0;
}
}
///\returns bool representing if Opcode \p Op can be part
/// of an alternate sequence which can later be merged as
/// a ShuffleVector instruction.
static bool canCombineAsAltInst(unsigned Op) {
if (Op == Instruction::FAdd || Op == Instruction::FSub ||
Op == Instruction::Sub || Op == Instruction::Add)
return true;
return false;
}
/// \returns ShuffleVector instruction if intructions in \p VL have
/// alternate fadd,fsub / fsub,fadd/add,sub/sub,add sequence.
/// (i.e. e.g. opcodes of fadd,fsub,fadd,fsub...)
static unsigned isAltInst(ArrayRef<Value *> VL) {
Instruction *I0 = dyn_cast<Instruction>(VL[0]);
unsigned Opcode = I0->getOpcode();
unsigned AltOpcode = getAltOpcode(Opcode);
for (int i = 1, e = VL.size(); i < e; i++) {
Instruction *I = dyn_cast<Instruction>(VL[i]);
if (!I || I->getOpcode() != ((i & 1) ? AltOpcode : Opcode))
return 0;
}
return Instruction::ShuffleVector;
}
/// \returns The opcode if all of the Instructions in \p VL have the same
/// opcode, or zero.
static unsigned getSameOpcode(ArrayRef<Value *> VL) {
Instruction *I0 = dyn_cast<Instruction>(VL[0]);
if (!I0)
return 0;
unsigned Opcode = I0->getOpcode();
for (int i = 1, e = VL.size(); i < e; i++) {
Instruction *I = dyn_cast<Instruction>(VL[i]);
if (!I || Opcode != I->getOpcode()) {
if (canCombineAsAltInst(Opcode) && i == 1)
return isAltInst(VL);
return 0;
}
}
return Opcode;
}
/// Get the intersection (logical and) of all of the potential IR flags
/// of each scalar operation (VL) that will be converted into a vector (I).
/// Flag set: NSW, NUW, exact, and all of fast-math.
static void propagateIRFlags(Value *I, ArrayRef<Value *> VL) {
if (auto *VecOp = dyn_cast<BinaryOperator>(I)) {
if (auto *Intersection = dyn_cast<BinaryOperator>(VL[0])) {
// Intersection is initialized to the 0th scalar,
// so start counting from index '1'.
for (int i = 1, e = VL.size(); i < e; ++i) {
if (auto *Scalar = dyn_cast<BinaryOperator>(VL[i]))
Intersection->andIRFlags(Scalar);
}
VecOp->copyIRFlags(Intersection);
}
}
}
/// \returns \p I after propagating metadata from \p VL.
static Instruction *propagateMetadata(Instruction *I, ArrayRef<Value *> VL) {
Instruction *I0 = cast<Instruction>(VL[0]);
SmallVector<std::pair<unsigned, MDNode *>, 4> Metadata;
I0->getAllMetadataOtherThanDebugLoc(Metadata);
for (unsigned i = 0, n = Metadata.size(); i != n; ++i) {
unsigned Kind = Metadata[i].first;
MDNode *MD = Metadata[i].second;
for (int i = 1, e = VL.size(); MD && i != e; i++) {
Instruction *I = cast<Instruction>(VL[i]);
MDNode *IMD = I->getMetadata(Kind);
switch (Kind) {
default:
MD = nullptr; // Remove unknown metadata
break;
case LLVMContext::MD_tbaa:
MD = MDNode::getMostGenericTBAA(MD, IMD);
break;
case LLVMContext::MD_alias_scope:
MD = MDNode::getMostGenericAliasScope(MD, IMD);
break;
case LLVMContext::MD_noalias:
MD = MDNode::intersect(MD, IMD);
break;
case LLVMContext::MD_fpmath:
MD = MDNode::getMostGenericFPMath(MD, IMD);
break;
}
}
I->setMetadata(Kind, MD);
}
return I;
}
/// \returns The type that all of the values in \p VL have or null if there
/// are different types.
static Type* getSameType(ArrayRef<Value *> VL) {
Type *Ty = VL[0]->getType();
for (int i = 1, e = VL.size(); i < e; i++)
if (VL[i]->getType() != Ty)
return nullptr;
return Ty;
}
/// \returns True if the ExtractElement instructions in VL can be vectorized
/// to use the original vector.
static bool CanReuseExtract(ArrayRef<Value *> VL) {
assert(Instruction::ExtractElement == getSameOpcode(VL) && "Invalid opcode");
// Check if all of the extracts come from the same vector and from the
// correct offset.
Value *VL0 = VL[0];
ExtractElementInst *E0 = cast<ExtractElementInst>(VL0);
Value *Vec = E0->getOperand(0);
// We have to extract from the same vector type.
unsigned NElts = Vec->getType()->getVectorNumElements();
if (NElts != VL.size())
return false;
// Check that all of the indices extract from the correct offset.
ConstantInt *CI = dyn_cast<ConstantInt>(E0->getOperand(1));
if (!CI || CI->getZExtValue())
return false;
for (unsigned i = 1, e = VL.size(); i < e; ++i) {
ExtractElementInst *E = cast<ExtractElementInst>(VL[i]);
ConstantInt *CI = dyn_cast<ConstantInt>(E->getOperand(1));
if (!CI || CI->getZExtValue() != i || E->getOperand(0) != Vec)
return false;
}
return true;
}
/// \returns True if in-tree use also needs extract. This refers to
/// possible scalar operand in vectorized instruction.
static bool InTreeUserNeedToExtract(Value *Scalar, Instruction *UserInst,
TargetLibraryInfo *TLI) {
unsigned Opcode = UserInst->getOpcode();
switch (Opcode) {
case Instruction::Load: {
LoadInst *LI = cast<LoadInst>(UserInst);
return (LI->getPointerOperand() == Scalar);
}
case Instruction::Store: {
StoreInst *SI = cast<StoreInst>(UserInst);
return (SI->getPointerOperand() == Scalar);
}
case Instruction::Call: {
CallInst *CI = cast<CallInst>(UserInst);
Intrinsic::ID ID = getIntrinsicIDForCall(CI, TLI);
if (hasVectorInstrinsicScalarOpd(ID, 1)) {
return (CI->getArgOperand(1) == Scalar);
}
}
default:
return false;
}
}
/// \returns the AA location that is being access by the instruction.
static MemoryLocation getLocation(Instruction *I, AliasAnalysis *AA) {
if (StoreInst *SI = dyn_cast<StoreInst>(I))
return MemoryLocation::get(SI);
if (LoadInst *LI = dyn_cast<LoadInst>(I))
return MemoryLocation::get(LI);
return MemoryLocation();
}
/// \returns True if the instruction is not a volatile or atomic load/store.
static bool isSimple(Instruction *I) {
if (LoadInst *LI = dyn_cast<LoadInst>(I))
return LI->isSimple();
if (StoreInst *SI = dyn_cast<StoreInst>(I))
return SI->isSimple();
if (MemIntrinsic *MI = dyn_cast<MemIntrinsic>(I))
return !MI->isVolatile();
return true;
}
/// Bottom Up SLP Vectorizer.
class BoUpSLP {
public:
typedef SmallVector<Value *, 8> ValueList;
typedef SmallVector<Instruction *, 16> InstrList;
typedef SmallPtrSet<Value *, 16> ValueSet;
typedef SmallVector<StoreInst *, 8> StoreList;
BoUpSLP(Function *Func, ScalarEvolution *Se, TargetTransformInfo *Tti,
TargetLibraryInfo *TLi, AliasAnalysis *Aa, LoopInfo *Li,
DominatorTree *Dt, AssumptionCache *AC)
: NumLoadsWantToKeepOrder(0), NumLoadsWantToChangeOrder(0), F(Func),
SE(Se), TTI(Tti), TLI(TLi), AA(Aa), LI(Li), DT(Dt),
Builder(Se->getContext()) {
CodeMetrics::collectEphemeralValues(F, AC, EphValues);
}
/// \brief Vectorize the tree that starts with the elements in \p VL.
/// Returns the vectorized root.
Value *vectorizeTree();
/// \returns the cost incurred by unwanted spills and fills, caused by
/// holding live values over call sites.
int getSpillCost();
/// \returns the vectorization cost of the subtree that starts at \p VL.
/// A negative number means that this is profitable.
int getTreeCost();
/// Construct a vectorizable tree that starts at \p Roots, ignoring users for
/// the purpose of scheduling and extraction in the \p UserIgnoreLst.
void buildTree(ArrayRef<Value *> Roots,
ArrayRef<Value *> UserIgnoreLst = None);
/// Clear the internal data structures that are created by 'buildTree'.
void deleteTree() {
VectorizableTree.clear();
ScalarToTreeEntry.clear();
MustGather.clear();
ExternalUses.clear();
NumLoadsWantToKeepOrder = 0;
NumLoadsWantToChangeOrder = 0;
for (auto &Iter : BlocksSchedules) {
BlockScheduling *BS = Iter.second.get();
BS->clear();
}
}
/// \returns true if the memory operations A and B are consecutive.
bool isConsecutiveAccess(Value *A, Value *B, const DataLayout &DL);
/// \brief Perform LICM and CSE on the newly generated gather sequences.
void optimizeGatherSequence();
/// \returns true if it is benefitial to reverse the vector order.
bool shouldReorder() const {
return NumLoadsWantToChangeOrder > NumLoadsWantToKeepOrder;
}
private:
struct TreeEntry;
/// \returns the cost of the vectorizable entry.
int getEntryCost(TreeEntry *E);
/// This is the recursive part of buildTree.
void buildTree_rec(ArrayRef<Value *> Roots, unsigned Depth);
/// Vectorize a single entry in the tree.
Value *vectorizeTree(TreeEntry *E);
/// Vectorize a single entry in the tree, starting in \p VL.
Value *vectorizeTree(ArrayRef<Value *> VL);
/// \returns the pointer to the vectorized value if \p VL is already
/// vectorized, or NULL. They may happen in cycles.
Value *alreadyVectorized(ArrayRef<Value *> VL) const;
/// \brief Take the pointer operand from the Load/Store instruction.
/// \returns NULL if this is not a valid Load/Store instruction.
static Value *getPointerOperand(Value *I);
/// \brief Take the address space operand from the Load/Store instruction.
/// \returns -1 if this is not a valid Load/Store instruction.
static unsigned getAddressSpaceOperand(Value *I);
/// \returns the scalarization cost for this type. Scalarization in this
/// context means the creation of vectors from a group of scalars.
int getGatherCost(Type *Ty);
/// \returns the scalarization cost for this list of values. Assuming that
/// this subtree gets vectorized, we may need to extract the values from the
/// roots. This method calculates the cost of extracting the values.
int getGatherCost(ArrayRef<Value *> VL);
/// \brief Set the Builder insert point to one after the last instruction in
/// the bundle
void setInsertPointAfterBundle(ArrayRef<Value *> VL);
/// \returns a vector from a collection of scalars in \p VL.
Value *Gather(ArrayRef<Value *> VL, VectorType *Ty);
/// \returns whether the VectorizableTree is fully vectoriable and will
/// be beneficial even the tree height is tiny.
bool isFullyVectorizableTinyTree();
/// \reorder commutative operands in alt shuffle if they result in
/// vectorized code.
void reorderAltShuffleOperands(ArrayRef<Value *> VL,
SmallVectorImpl<Value *> &Left,
SmallVectorImpl<Value *> &Right);
/// \reorder commutative operands to get better probability of
/// generating vectorized code.
void reorderInputsAccordingToOpcode(ArrayRef<Value *> VL,
SmallVectorImpl<Value *> &Left,
SmallVectorImpl<Value *> &Right);
struct TreeEntry {
TreeEntry() : Scalars(), VectorizedValue(nullptr),
NeedToGather(0) {}
/// \returns true if the scalars in VL are equal to this entry.
bool isSame(ArrayRef<Value *> VL) const {
assert(VL.size() == Scalars.size() && "Invalid size");
return std::equal(VL.begin(), VL.end(), Scalars.begin());
}
/// A vector of scalars.
ValueList Scalars;
/// The Scalars are vectorized into this value. It is initialized to Null.
Value *VectorizedValue;
/// Do we need to gather this sequence ?
bool NeedToGather;
};
/// Create a new VectorizableTree entry.
TreeEntry *newTreeEntry(ArrayRef<Value *> VL, bool Vectorized) {
VectorizableTree.emplace_back();
int idx = VectorizableTree.size() - 1;
TreeEntry *Last = &VectorizableTree[idx];
Last->Scalars.insert(Last->Scalars.begin(), VL.begin(), VL.end());
Last->NeedToGather = !Vectorized;
if (Vectorized) {
for (int i = 0, e = VL.size(); i != e; ++i) {
assert(!ScalarToTreeEntry.count(VL[i]) && "Scalar already in tree!");
ScalarToTreeEntry[VL[i]] = idx;
}
} else {
MustGather.insert(VL.begin(), VL.end());
}
return Last;
}
/// -- Vectorization State --
/// Holds all of the tree entries.
std::vector<TreeEntry> VectorizableTree;
/// Maps a specific scalar to its tree entry.
SmallDenseMap<Value*, int> ScalarToTreeEntry;
/// A list of scalars that we found that we need to keep as scalars.
ValueSet MustGather;
/// This POD struct describes one external user in the vectorized tree.
struct ExternalUser {
ExternalUser (Value *S, llvm::User *U, int L) :
Scalar(S), User(U), Lane(L){};
// Which scalar in our function.
Value *Scalar;
// Which user that uses the scalar.
llvm::User *User;
// Which lane does the scalar belong to.
int Lane;
};
typedef SmallVector<ExternalUser, 16> UserList;
/// Checks if two instructions may access the same memory.
///
/// \p Loc1 is the location of \p Inst1. It is passed explicitly because it
/// is invariant in the calling loop.
bool isAliased(const MemoryLocation &Loc1, Instruction *Inst1,
Instruction *Inst2) {
// First check if the result is already in the cache.
AliasCacheKey key = std::make_pair(Inst1, Inst2);
Optional<bool> &result = AliasCache[key];
if (result.hasValue()) {
return result.getValue();
}
MemoryLocation Loc2 = getLocation(Inst2, AA);
bool aliased = true;
if (Loc1.Ptr && Loc2.Ptr && isSimple(Inst1) && isSimple(Inst2)) {
// Do the alias check.
aliased = AA->alias(Loc1, Loc2);
}
// Store the result in the cache.
result = aliased;
return aliased;
}
typedef std::pair<Instruction *, Instruction *> AliasCacheKey;
/// Cache for alias results.
/// TODO: consider moving this to the AliasAnalysis itself.
DenseMap<AliasCacheKey, Optional<bool>> AliasCache;
/// Removes an instruction from its block and eventually deletes it.
/// It's like Instruction::eraseFromParent() except that the actual deletion
/// is delayed until BoUpSLP is destructed.
/// This is required to ensure that there are no incorrect collisions in the
/// AliasCache, which can happen if a new instruction is allocated at the
/// same address as a previously deleted instruction.
void eraseInstruction(Instruction *I) {
I->removeFromParent();
I->dropAllReferences();
DeletedInstructions.push_back(std::unique_ptr<Instruction>(I));
}
/// Temporary store for deleted instructions. Instructions will be deleted
/// eventually when the BoUpSLP is destructed.
SmallVector<std::unique_ptr<Instruction>, 8> DeletedInstructions;
/// A list of values that need to extracted out of the tree.
/// This list holds pairs of (Internal Scalar : External User).
UserList ExternalUses;
/// Values used only by @llvm.assume calls.
SmallPtrSet<const Value *, 32> EphValues;
/// Holds all of the instructions that we gathered.
SetVector<Instruction *> GatherSeq;
/// A list of blocks that we are going to CSE.
SetVector<BasicBlock *> CSEBlocks;
/// Contains all scheduling relevant data for an instruction.
/// A ScheduleData either represents a single instruction or a member of an
/// instruction bundle (= a group of instructions which is combined into a
/// vector instruction).
struct ScheduleData {
// The initial value for the dependency counters. It means that the
// dependencies are not calculated yet.
enum { InvalidDeps = -1 };
ScheduleData()
: Inst(nullptr), FirstInBundle(nullptr), NextInBundle(nullptr),
NextLoadStore(nullptr), SchedulingRegionID(0), SchedulingPriority(0),
Dependencies(InvalidDeps), UnscheduledDeps(InvalidDeps),
UnscheduledDepsInBundle(InvalidDeps), IsScheduled(false) {}
void init(int BlockSchedulingRegionID) {
FirstInBundle = this;
NextInBundle = nullptr;
NextLoadStore = nullptr;
IsScheduled = false;
SchedulingRegionID = BlockSchedulingRegionID;
UnscheduledDepsInBundle = UnscheduledDeps;
clearDependencies();
}
/// Returns true if the dependency information has been calculated.
bool hasValidDependencies() const { return Dependencies != InvalidDeps; }
/// Returns true for single instructions and for bundle representatives
/// (= the head of a bundle).
bool isSchedulingEntity() const { return FirstInBundle == this; }
/// Returns true if it represents an instruction bundle and not only a
/// single instruction.
bool isPartOfBundle() const {
return NextInBundle != nullptr || FirstInBundle != this;
}
/// Returns true if it is ready for scheduling, i.e. it has no more
/// unscheduled depending instructions/bundles.
bool isReady() const {
assert(isSchedulingEntity() &&
"can't consider non-scheduling entity for ready list");
return UnscheduledDepsInBundle == 0 && !IsScheduled;
}
/// Modifies the number of unscheduled dependencies, also updating it for
/// the whole bundle.
int incrementUnscheduledDeps(int Incr) {
UnscheduledDeps += Incr;
return FirstInBundle->UnscheduledDepsInBundle += Incr;
}
/// Sets the number of unscheduled dependencies to the number of
/// dependencies.
void resetUnscheduledDeps() {
incrementUnscheduledDeps(Dependencies - UnscheduledDeps);
}
/// Clears all dependency information.
void clearDependencies() {
Dependencies = InvalidDeps;
resetUnscheduledDeps();
MemoryDependencies.clear();
}
void dump(raw_ostream &os) const {
if (!isSchedulingEntity()) {
os << "/ " << *Inst;
} else if (NextInBundle) {
os << '[' << *Inst;
ScheduleData *SD = NextInBundle;
while (SD) {
os << ';' << *SD->Inst;
SD = SD->NextInBundle;
}
os << ']';
} else {
os << *Inst;
}
}
Instruction *Inst;
/// Points to the head in an instruction bundle (and always to this for
/// single instructions).
ScheduleData *FirstInBundle;
/// Single linked list of all instructions in a bundle. Null if it is a
/// single instruction.
ScheduleData *NextInBundle;
/// Single linked list of all memory instructions (e.g. load, store, call)
/// in the block - until the end of the scheduling region.
ScheduleData *NextLoadStore;
/// The dependent memory instructions.
/// This list is derived on demand in calculateDependencies().
SmallVector<ScheduleData *, 4> MemoryDependencies;
/// This ScheduleData is in the current scheduling region if this matches
/// the current SchedulingRegionID of BlockScheduling.
int SchedulingRegionID;
/// Used for getting a "good" final ordering of instructions.
int SchedulingPriority;
/// The number of dependencies. Constitutes of the number of users of the
/// instruction plus the number of dependent memory instructions (if any).
/// This value is calculated on demand.
/// If InvalidDeps, the number of dependencies is not calculated yet.
///
int Dependencies;
/// The number of dependencies minus the number of dependencies of scheduled
/// instructions. As soon as this is zero, the instruction/bundle gets ready
/// for scheduling.
/// Note that this is negative as long as Dependencies is not calculated.
int UnscheduledDeps;
/// The sum of UnscheduledDeps in a bundle. Equals to UnscheduledDeps for
/// single instructions.
int UnscheduledDepsInBundle;
/// True if this instruction is scheduled (or considered as scheduled in the
/// dry-run).
bool IsScheduled;
};
#ifndef NDEBUG
friend raw_ostream &operator<<(raw_ostream &os,
const BoUpSLP::ScheduleData &SD);
#endif
/// Contains all scheduling data for a basic block.
///
struct BlockScheduling {
BlockScheduling(BasicBlock *BB)
: BB(BB), ChunkSize(BB->size()), ChunkPos(ChunkSize),
ScheduleStart(nullptr), ScheduleEnd(nullptr),
FirstLoadStoreInRegion(nullptr), LastLoadStoreInRegion(nullptr),
// Make sure that the initial SchedulingRegionID is greater than the
// initial SchedulingRegionID in ScheduleData (which is 0).
SchedulingRegionID(1) {}
void clear() {
ReadyInsts.clear();
ScheduleStart = nullptr;
ScheduleEnd = nullptr;
FirstLoadStoreInRegion = nullptr;
LastLoadStoreInRegion = nullptr;
// Make a new scheduling region, i.e. all existing ScheduleData is not
// in the new region yet.
++SchedulingRegionID;
}
ScheduleData *getScheduleData(Value *V) {
ScheduleData *SD = ScheduleDataMap[V];
if (SD && SD->SchedulingRegionID == SchedulingRegionID)
return SD;
return nullptr;
}
bool isInSchedulingRegion(ScheduleData *SD) {
return SD->SchedulingRegionID == SchedulingRegionID;
}
/// Marks an instruction as scheduled and puts all dependent ready
/// instructions into the ready-list.
template <typename ReadyListType>
void schedule(ScheduleData *SD, ReadyListType &ReadyList) {
SD->IsScheduled = true;
DEBUG(dbgs() << "SLP: schedule " << *SD << "\n");
ScheduleData *BundleMember = SD;
while (BundleMember) {
// Handle the def-use chain dependencies.
for (Use &U : BundleMember->Inst->operands()) {
ScheduleData *OpDef = getScheduleData(U.get());
if (OpDef && OpDef->hasValidDependencies() &&
OpDef->incrementUnscheduledDeps(-1) == 0) {
// There are no more unscheduled dependencies after decrementing,
// so we can put the dependent instruction into the ready list.
ScheduleData *DepBundle = OpDef->FirstInBundle;
assert(!DepBundle->IsScheduled &&
"already scheduled bundle gets ready");
ReadyList.insert(DepBundle);
DEBUG(dbgs() << "SLP: gets ready (def): " << *DepBundle << "\n");
}
}
// Handle the memory dependencies.
for (ScheduleData *MemoryDepSD : BundleMember->MemoryDependencies) {
if (MemoryDepSD->incrementUnscheduledDeps(-1) == 0) {
// There are no more unscheduled dependencies after decrementing,
// so we can put the dependent instruction into the ready list.
ScheduleData *DepBundle = MemoryDepSD->FirstInBundle;
assert(!DepBundle->IsScheduled &&
"already scheduled bundle gets ready");
ReadyList.insert(DepBundle);
DEBUG(dbgs() << "SLP: gets ready (mem): " << *DepBundle << "\n");
}
}
BundleMember = BundleMember->NextInBundle;
}
}
/// Put all instructions into the ReadyList which are ready for scheduling.
template <typename ReadyListType>
void initialFillReadyList(ReadyListType &ReadyList) {
for (auto *I = ScheduleStart; I != ScheduleEnd; I = I->getNextNode()) {
ScheduleData *SD = getScheduleData(I);
if (SD->isSchedulingEntity() && SD->isReady()) {
ReadyList.insert(SD);
DEBUG(dbgs() << "SLP: initially in ready list: " << *I << "\n");
}
}
}
/// Checks if a bundle of instructions can be scheduled, i.e. has no
/// cyclic dependencies. This is only a dry-run, no instructions are
/// actually moved at this stage.
bool tryScheduleBundle(ArrayRef<Value *> VL, BoUpSLP *SLP);
/// Un-bundles a group of instructions.
void cancelScheduling(ArrayRef<Value *> VL);
/// Extends the scheduling region so that V is inside the region.
void extendSchedulingRegion(Value *V);
/// Initialize the ScheduleData structures for new instructions in the
/// scheduling region.
void initScheduleData(Instruction *FromI, Instruction *ToI,
ScheduleData *PrevLoadStore,
ScheduleData *NextLoadStore);
/// Updates the dependency information of a bundle and of all instructions/
/// bundles which depend on the original bundle.
void calculateDependencies(ScheduleData *SD, bool InsertInReadyList,
BoUpSLP *SLP);
/// Sets all instruction in the scheduling region to un-scheduled.
void resetSchedule();
BasicBlock *BB;
/// Simple memory allocation for ScheduleData.
std::vector<std::unique_ptr<ScheduleData[]>> ScheduleDataChunks;
/// The size of a ScheduleData array in ScheduleDataChunks.
int ChunkSize;
/// The allocator position in the current chunk, which is the last entry
/// of ScheduleDataChunks.
int ChunkPos;
/// Attaches ScheduleData to Instruction.
/// Note that the mapping survives during all vectorization iterations, i.e.
/// ScheduleData structures are recycled.
DenseMap<Value *, ScheduleData *> ScheduleDataMap;
struct ReadyList : SmallVector<ScheduleData *, 8> {
void insert(ScheduleData *SD) { push_back(SD); }
};
/// The ready-list for scheduling (only used for the dry-run).
ReadyList ReadyInsts;
/// The first instruction of the scheduling region.
Instruction *ScheduleStart;
/// The first instruction _after_ the scheduling region.
Instruction *ScheduleEnd;
/// The first memory accessing instruction in the scheduling region
/// (can be null).
ScheduleData *FirstLoadStoreInRegion;
/// The last memory accessing instruction in the scheduling region
/// (can be null).
ScheduleData *LastLoadStoreInRegion;
/// The ID of the scheduling region. For a new vectorization iteration this
/// is incremented which "removes" all ScheduleData from the region.
int SchedulingRegionID;
};
/// Attaches the BlockScheduling structures to basic blocks.
MapVector<BasicBlock *, std::unique_ptr<BlockScheduling>> BlocksSchedules;
/// Performs the "real" scheduling. Done before vectorization is actually
/// performed in a basic block.
void scheduleBlock(BlockScheduling *BS);
/// List of users to ignore during scheduling and that don't need extracting.
ArrayRef<Value *> UserIgnoreList;
// Number of load-bundles, which contain consecutive loads.
int NumLoadsWantToKeepOrder;
// Number of load-bundles of size 2, which are consecutive loads if reversed.
int NumLoadsWantToChangeOrder;
// Analysis and block reference.
Function *F;
ScalarEvolution *SE;
TargetTransformInfo *TTI;
TargetLibraryInfo *TLI;
AliasAnalysis *AA;
LoopInfo *LI;
DominatorTree *DT;
/// Instruction builder to construct the vectorized tree.
IRBuilder<> Builder;
};
#ifndef NDEBUG
raw_ostream &operator<<(raw_ostream &os, const BoUpSLP::ScheduleData &SD) {
SD.dump(os);
return os;
}
#endif
void BoUpSLP::buildTree(ArrayRef<Value *> Roots,
ArrayRef<Value *> UserIgnoreLst) {
deleteTree();
UserIgnoreList = UserIgnoreLst;
if (!getSameType(Roots))
return;
buildTree_rec(Roots, 0);
// Collect the values that we need to extract from the tree.
for (int EIdx = 0, EE = VectorizableTree.size(); EIdx < EE; ++EIdx) {
TreeEntry *Entry = &VectorizableTree[EIdx];
// For each lane:
for (int Lane = 0, LE = Entry->Scalars.size(); Lane != LE; ++Lane) {
Value *Scalar = Entry->Scalars[Lane];
// No need to handle users of gathered values.
if (Entry->NeedToGather)
continue;
for (User *U : Scalar->users()) {
DEBUG(dbgs() << "SLP: Checking user:" << *U << ".\n");
Instruction *UserInst = dyn_cast<Instruction>(U);
if (!UserInst)
continue;
// Skip in-tree scalars that become vectors
if (ScalarToTreeEntry.count(U)) {
int Idx = ScalarToTreeEntry[U];
TreeEntry *UseEntry = &VectorizableTree[Idx];
Value *UseScalar = UseEntry->Scalars[0];
// Some in-tree scalars will remain as scalar in vectorized
// instructions. If that is the case, the one in Lane 0 will
// be used.
if (UseScalar != U ||
!InTreeUserNeedToExtract(Scalar, UserInst, TLI)) {
DEBUG(dbgs() << "SLP: \tInternal user will be removed:" << *U
<< ".\n");
assert(!VectorizableTree[Idx].NeedToGather && "Bad state");
continue;
}
}
// Ignore users in the user ignore list.
if (std::find(UserIgnoreList.begin(), UserIgnoreList.end(), UserInst) !=
UserIgnoreList.end())
continue;
DEBUG(dbgs() << "SLP: Need to extract:" << *U << " from lane " <<
Lane << " from " << *Scalar << ".\n");
ExternalUses.push_back(ExternalUser(Scalar, U, Lane));
}
}
}
}
void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth) {
bool SameTy = getSameType(VL); (void)SameTy;
bool isAltShuffle = false;
assert(SameTy && "Invalid types!");
if (Depth == RecursionMaxDepth) {
DEBUG(dbgs() << "SLP: Gathering due to max recursion depth.\n");
newTreeEntry(VL, false);
return;
}
// Don't handle vectors.
if (VL[0]->getType()->isVectorTy()) {
DEBUG(dbgs() << "SLP: Gathering due to vector type.\n");
newTreeEntry(VL, false);
return;
}
if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
if (SI->getValueOperand()->getType()->isVectorTy()) {
DEBUG(dbgs() << "SLP: Gathering due to store vector type.\n");
newTreeEntry(VL, false);
return;
}
unsigned Opcode = getSameOpcode(VL);
// Check that this shuffle vector refers to the alternate
// sequence of opcodes.
if (Opcode == Instruction::ShuffleVector) {
Instruction *I0 = dyn_cast<Instruction>(VL[0]);
unsigned Op = I0->getOpcode();
if (Op != Instruction::ShuffleVector)
isAltShuffle = true;
}
// If all of the operands are identical or constant we have a simple solution.
if (allConstant(VL) || isSplat(VL) || !getSameBlock(VL) || !Opcode) {
DEBUG(dbgs() << "SLP: Gathering due to C,S,B,O. \n");
newTreeEntry(VL, false);
return;
}
// We now know that this is a vector of instructions of the same type from
// the same block.
// Don't vectorize ephemeral values.
for (unsigned i = 0, e = VL.size(); i != e; ++i) {
if (EphValues.count(VL[i])) {
DEBUG(dbgs() << "SLP: The instruction (" << *VL[i] <<
") is ephemeral.\n");
newTreeEntry(VL, false);
return;
}
}
// Check if this is a duplicate of another entry.
if (ScalarToTreeEntry.count(VL[0])) {
int Idx = ScalarToTreeEntry[VL[0]];
TreeEntry *E = &VectorizableTree[Idx];
for (unsigned i = 0, e = VL.size(); i != e; ++i) {
DEBUG(dbgs() << "SLP: \tChecking bundle: " << *VL[i] << ".\n");
if (E->Scalars[i] != VL[i]) {
DEBUG(dbgs() << "SLP: Gathering due to partial overlap.\n");
newTreeEntry(VL, false);
return;
}
}
DEBUG(dbgs() << "SLP: Perfect diamond merge at " << *VL[0] << ".\n");
return;
}
// Check that none of the instructions in the bundle are already in the tree.
for (unsigned i = 0, e = VL.size(); i != e; ++i) {
if (ScalarToTreeEntry.count(VL[i])) {
DEBUG(dbgs() << "SLP: The instruction (" << *VL[i] <<
") is already in tree.\n");
newTreeEntry(VL, false);
return;
}
}
// If any of the scalars is marked as a value that needs to stay scalar then
// we need to gather the scalars.
for (unsigned i = 0, e = VL.size(); i != e; ++i) {
if (MustGather.count(VL[i])) {
DEBUG(dbgs() << "SLP: Gathering due to gathered scalar.\n");
newTreeEntry(VL, false);
return;
}
}
// Check that all of the users of the scalars that we want to vectorize are
// schedulable.
Instruction *VL0 = cast<Instruction>(VL[0]);
BasicBlock *BB = cast<Instruction>(VL0)->getParent();
if (!DT->isReachableFromEntry(BB)) {
// Don't go into unreachable blocks. They may contain instructions with
// dependency cycles which confuse the final scheduling.
DEBUG(dbgs() << "SLP: bundle in unreachable block.\n");
newTreeEntry(VL, false);
return;
}
// Check that every instructions appears once in this bundle.
for (unsigned i = 0, e = VL.size(); i < e; ++i)
for (unsigned j = i+1; j < e; ++j)
if (VL[i] == VL[j]) {
DEBUG(dbgs() << "SLP: Scalar used twice in bundle.\n");
newTreeEntry(VL, false);
return;
}
auto &BSRef = BlocksSchedules[BB];
if (!BSRef) {
BSRef = llvm::make_unique<BlockScheduling>(BB);
}
BlockScheduling &BS = *BSRef.get();
if (!BS.tryScheduleBundle(VL, this)) {
DEBUG(dbgs() << "SLP: We are not able to schedule this bundle!\n");
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
return;
}
DEBUG(dbgs() << "SLP: We are able to schedule this bundle.\n");
switch (Opcode) {
case Instruction::PHI: {
PHINode *PH = dyn_cast<PHINode>(VL0);
// Check for terminator values (e.g. invoke).
for (unsigned j = 0; j < VL.size(); ++j)
for (unsigned i = 0, e = PH->getNumIncomingValues(); i < e; ++i) {
TerminatorInst *Term = dyn_cast<TerminatorInst>(
cast<PHINode>(VL[j])->getIncomingValueForBlock(PH->getIncomingBlock(i)));
if (Term) {
DEBUG(dbgs() << "SLP: Need to swizzle PHINodes (TerminatorInst use).\n");
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
return;
}
}
newTreeEntry(VL, true);
DEBUG(dbgs() << "SLP: added a vector of PHINodes.\n");
for (unsigned i = 0, e = PH->getNumIncomingValues(); i < e; ++i) {
ValueList Operands;
// Prepare the operand vector.
for (unsigned j = 0; j < VL.size(); ++j)
Operands.push_back(cast<PHINode>(VL[j])->getIncomingValueForBlock(
PH->getIncomingBlock(i)));
buildTree_rec(Operands, Depth + 1);
}
return;
}
case Instruction::ExtractElement: {
bool Reuse = CanReuseExtract(VL);
if (Reuse) {
DEBUG(dbgs() << "SLP: Reusing extract sequence.\n");
} else {
BS.cancelScheduling(VL);
}
newTreeEntry(VL, Reuse);
return;
}
case Instruction::Load: {
// Check if the loads are consecutive or of we need to swizzle them.
for (unsigned i = 0, e = VL.size() - 1; i < e; ++i) {
LoadInst *L = cast<LoadInst>(VL[i]);
if (!L->isSimple()) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
DEBUG(dbgs() << "SLP: Gathering non-simple loads.\n");
return;
}
const DataLayout &DL = F->getParent()->getDataLayout();
if (!isConsecutiveAccess(VL[i], VL[i + 1], DL)) {
if (VL.size() == 2 && isConsecutiveAccess(VL[1], VL[0], DL)) {
++NumLoadsWantToChangeOrder;
}
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
DEBUG(dbgs() << "SLP: Gathering non-consecutive loads.\n");
return;
}
}
++NumLoadsWantToKeepOrder;
newTreeEntry(VL, true);
DEBUG(dbgs() << "SLP: added a vector of loads.\n");
return;
}
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::FPToUI:
case Instruction::FPToSI:
case Instruction::FPExt:
case Instruction::PtrToInt:
case Instruction::IntToPtr:
case Instruction::SIToFP:
case Instruction::UIToFP:
case Instruction::Trunc:
case Instruction::FPTrunc:
case Instruction::BitCast: {
Type *SrcTy = VL0->getOperand(0)->getType();
for (unsigned i = 0; i < VL.size(); ++i) {
Type *Ty = cast<Instruction>(VL[i])->getOperand(0)->getType();
if (Ty != SrcTy || !isValidElementType(Ty)) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
DEBUG(dbgs() << "SLP: Gathering casts with different src types.\n");
return;
}
}
newTreeEntry(VL, true);
DEBUG(dbgs() << "SLP: added a vector of casts.\n");
for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
ValueList Operands;
// Prepare the operand vector.
for (unsigned j = 0; j < VL.size(); ++j)
Operands.push_back(cast<Instruction>(VL[j])->getOperand(i));
buildTree_rec(Operands, Depth+1);
}
return;
}
case Instruction::ICmp:
case Instruction::FCmp: {
// Check that all of the compares have the same predicate.
CmpInst::Predicate P0 = cast<CmpInst>(VL0)->getPredicate();
Type *ComparedTy = cast<Instruction>(VL[0])->getOperand(0)->getType();
for (unsigned i = 1, e = VL.size(); i < e; ++i) {
CmpInst *Cmp = cast<CmpInst>(VL[i]);
if (Cmp->getPredicate() != P0 ||
Cmp->getOperand(0)->getType() != ComparedTy) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
DEBUG(dbgs() << "SLP: Gathering cmp with different predicate.\n");
return;
}
}
newTreeEntry(VL, true);
DEBUG(dbgs() << "SLP: added a vector of compares.\n");
for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
ValueList Operands;
// Prepare the operand vector.
for (unsigned j = 0; j < VL.size(); ++j)
Operands.push_back(cast<Instruction>(VL[j])->getOperand(i));
buildTree_rec(Operands, Depth+1);
}
return;
}
case Instruction::Select:
case Instruction::Add:
case Instruction::FAdd:
case Instruction::Sub:
case Instruction::FSub:
case Instruction::Mul:
case Instruction::FMul:
case Instruction::UDiv:
case Instruction::SDiv:
case Instruction::FDiv:
case Instruction::URem:
case Instruction::SRem:
case Instruction::FRem:
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor: {
newTreeEntry(VL, true);
DEBUG(dbgs() << "SLP: added a vector of bin op.\n");
// Sort operands of the instructions so that each side is more likely to
// have the same opcode.
if (isa<BinaryOperator>(VL0) && VL0->isCommutative()) {
ValueList Left, Right;
reorderInputsAccordingToOpcode(VL, Left, Right);
buildTree_rec(Left, Depth + 1);
buildTree_rec(Right, Depth + 1);
return;
}
for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
ValueList Operands;
// Prepare the operand vector.
for (unsigned j = 0; j < VL.size(); ++j)
Operands.push_back(cast<Instruction>(VL[j])->getOperand(i));
buildTree_rec(Operands, Depth+1);
}
return;
}
case Instruction::GetElementPtr: {
// We don't combine GEPs with complicated (nested) indexing.
for (unsigned j = 0; j < VL.size(); ++j) {
if (cast<Instruction>(VL[j])->getNumOperands() != 2) {
DEBUG(dbgs() << "SLP: not-vectorizable GEP (nested indexes).\n");
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
return;
}
}
// We can't combine several GEPs into one vector if they operate on
// different types.
Type *Ty0 = cast<Instruction>(VL0)->getOperand(0)->getType();
for (unsigned j = 0; j < VL.size(); ++j) {
Type *CurTy = cast<Instruction>(VL[j])->getOperand(0)->getType();
if (Ty0 != CurTy) {
DEBUG(dbgs() << "SLP: not-vectorizable GEP (different types).\n");
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
return;
}
}
// We don't combine GEPs with non-constant indexes.
for (unsigned j = 0; j < VL.size(); ++j) {
auto Op = cast<Instruction>(VL[j])->getOperand(1);
if (!isa<ConstantInt>(Op)) {
DEBUG(
dbgs() << "SLP: not-vectorizable GEP (non-constant indexes).\n");
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
return;
}
}
newTreeEntry(VL, true);
DEBUG(dbgs() << "SLP: added a vector of GEPs.\n");
for (unsigned i = 0, e = 2; i < e; ++i) {
ValueList Operands;
// Prepare the operand vector.
for (unsigned j = 0; j < VL.size(); ++j)
Operands.push_back(cast<Instruction>(VL[j])->getOperand(i));
buildTree_rec(Operands, Depth + 1);
}
return;
}
case Instruction::Store: {
const DataLayout &DL = F->getParent()->getDataLayout();
// Check if the stores are consecutive or of we need to swizzle them.
for (unsigned i = 0, e = VL.size() - 1; i < e; ++i)
if (!isConsecutiveAccess(VL[i], VL[i + 1], DL)) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
DEBUG(dbgs() << "SLP: Non-consecutive store.\n");
return;
}
newTreeEntry(VL, true);
DEBUG(dbgs() << "SLP: added a vector of stores.\n");
ValueList Operands;
for (unsigned j = 0; j < VL.size(); ++j)
Operands.push_back(cast<Instruction>(VL[j])->getOperand(0));
buildTree_rec(Operands, Depth + 1);
return;
}
case Instruction::Call: {
// Check if the calls are all to the same vectorizable intrinsic.
CallInst *CI = cast<CallInst>(VL[0]);
// Check if this is an Intrinsic call or something that can be
// represented by an intrinsic call
Intrinsic::ID ID = getIntrinsicIDForCall(CI, TLI);
if (!isTriviallyVectorizable(ID)) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
DEBUG(dbgs() << "SLP: Non-vectorizable call.\n");
return;
}
Function *Int = CI->getCalledFunction();
Value *A1I = nullptr;
if (hasVectorInstrinsicScalarOpd(ID, 1))
A1I = CI->getArgOperand(1);
for (unsigned i = 1, e = VL.size(); i != e; ++i) {
CallInst *CI2 = dyn_cast<CallInst>(VL[i]);
if (!CI2 || CI2->getCalledFunction() != Int ||
getIntrinsicIDForCall(CI2, TLI) != ID) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
DEBUG(dbgs() << "SLP: mismatched calls:" << *CI << "!=" << *VL[i]
<< "\n");
return;
}
// ctlz,cttz and powi are special intrinsics whose second argument
// should be same in order for them to be vectorized.
if (hasVectorInstrinsicScalarOpd(ID, 1)) {
Value *A1J = CI2->getArgOperand(1);
if (A1I != A1J) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
DEBUG(dbgs() << "SLP: mismatched arguments in call:" << *CI
<< " argument "<< A1I<<"!=" << A1J
<< "\n");
return;
}
}
}
newTreeEntry(VL, true);
for (unsigned i = 0, e = CI->getNumArgOperands(); i != e; ++i) {
ValueList Operands;
// Prepare the operand vector.
for (unsigned j = 0; j < VL.size(); ++j) {
CallInst *CI2 = dyn_cast<CallInst>(VL[j]);
Operands.push_back(CI2->getArgOperand(i));
}
buildTree_rec(Operands, Depth + 1);
}
return;
}
case Instruction::ShuffleVector: {
// If this is not an alternate sequence of opcode like add-sub
// then do not vectorize this instruction.
if (!isAltShuffle) {
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
DEBUG(dbgs() << "SLP: ShuffleVector are not vectorized.\n");
return;
}
newTreeEntry(VL, true);
DEBUG(dbgs() << "SLP: added a ShuffleVector op.\n");
// Reorder operands if reordering would enable vectorization.
if (isa<BinaryOperator>(VL0)) {
ValueList Left, Right;
reorderAltShuffleOperands(VL, Left, Right);
buildTree_rec(Left, Depth + 1);
buildTree_rec(Right, Depth + 1);
return;
}
for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
ValueList Operands;
// Prepare the operand vector.
for (unsigned j = 0; j < VL.size(); ++j)
Operands.push_back(cast<Instruction>(VL[j])->getOperand(i));
buildTree_rec(Operands, Depth + 1);
}
return;
}
default:
BS.cancelScheduling(VL);
newTreeEntry(VL, false);
DEBUG(dbgs() << "SLP: Gathering unknown instruction.\n");
return;
}
}
int BoUpSLP::getEntryCost(TreeEntry *E) {
ArrayRef<Value*> VL = E->Scalars;
Type *ScalarTy = VL[0]->getType();
if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
ScalarTy = SI->getValueOperand()->getType();
VectorType *VecTy = VectorType::get(ScalarTy, VL.size());
if (E->NeedToGather) {
if (allConstant(VL))
return 0;
if (isSplat(VL)) {
return TTI->getShuffleCost(TargetTransformInfo::SK_Broadcast, VecTy, 0);
}
return getGatherCost(E->Scalars);
}
unsigned Opcode = getSameOpcode(VL);
assert(Opcode && getSameType(VL) && getSameBlock(VL) && "Invalid VL");
Instruction *VL0 = cast<Instruction>(VL[0]);
switch (Opcode) {
case Instruction::PHI: {
return 0;
}
case Instruction::ExtractElement: {
if (CanReuseExtract(VL)) {
int DeadCost = 0;
for (unsigned i = 0, e = VL.size(); i < e; ++i) {
ExtractElementInst *E = cast<ExtractElementInst>(VL[i]);
if (E->hasOneUse())
// Take credit for instruction that will become dead.
DeadCost +=
TTI->getVectorInstrCost(Instruction::ExtractElement, VecTy, i);
}
return -DeadCost;
}
return getGatherCost(VecTy);
}
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::FPToUI:
case Instruction::FPToSI:
case Instruction::FPExt:
case Instruction::PtrToInt:
case Instruction::IntToPtr:
case Instruction::SIToFP:
case Instruction::UIToFP:
case Instruction::Trunc:
case Instruction::FPTrunc:
case Instruction::BitCast: {
Type *SrcTy = VL0->getOperand(0)->getType();
// Calculate the cost of this instruction.
int ScalarCost = VL.size() * TTI->getCastInstrCost(VL0->getOpcode(),
VL0->getType(), SrcTy);
VectorType *SrcVecTy = VectorType::get(SrcTy, VL.size());
int VecCost = TTI->getCastInstrCost(VL0->getOpcode(), VecTy, SrcVecTy);
return VecCost - ScalarCost;
}
case Instruction::FCmp:
case Instruction::ICmp:
case Instruction::Select:
case Instruction::Add:
case Instruction::FAdd:
case Instruction::Sub:
case Instruction::FSub:
case Instruction::Mul:
case Instruction::FMul:
case Instruction::UDiv:
case Instruction::SDiv:
case Instruction::FDiv:
case Instruction::URem:
case Instruction::SRem:
case Instruction::FRem:
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor: {
// Calculate the cost of this instruction.
int ScalarCost = 0;
int VecCost = 0;
if (Opcode == Instruction::FCmp || Opcode == Instruction::ICmp ||
Opcode == Instruction::Select) {
VectorType *MaskTy = VectorType::get(Builder.getInt1Ty(), VL.size());
ScalarCost = VecTy->getNumElements() *
TTI->getCmpSelInstrCost(Opcode, ScalarTy, Builder.getInt1Ty());
VecCost = TTI->getCmpSelInstrCost(Opcode, VecTy, MaskTy);
} else {
// Certain instructions can be cheaper to vectorize if they have a
// constant second vector operand.
TargetTransformInfo::OperandValueKind Op1VK =
TargetTransformInfo::OK_AnyValue;
TargetTransformInfo::OperandValueKind Op2VK =
TargetTransformInfo::OK_UniformConstantValue;
TargetTransformInfo::OperandValueProperties Op1VP =
TargetTransformInfo::OP_None;
TargetTransformInfo::OperandValueProperties Op2VP =
TargetTransformInfo::OP_None;
// If all operands are exactly the same ConstantInt then set the
// operand kind to OK_UniformConstantValue.
// If instead not all operands are constants, then set the operand kind
// to OK_AnyValue. If all operands are constants but not the same,
// then set the operand kind to OK_NonUniformConstantValue.
ConstantInt *CInt = nullptr;
for (unsigned i = 0; i < VL.size(); ++i) {
const Instruction *I = cast<Instruction>(VL[i]);
if (!isa<ConstantInt>(I->getOperand(1))) {
Op2VK = TargetTransformInfo::OK_AnyValue;
break;
}
if (i == 0) {
CInt = cast<ConstantInt>(I->getOperand(1));
continue;
}
if (Op2VK == TargetTransformInfo::OK_UniformConstantValue &&
CInt != cast<ConstantInt>(I->getOperand(1)))
Op2VK = TargetTransformInfo::OK_NonUniformConstantValue;
}
// FIXME: Currently cost of model modification for division by
// power of 2 is handled only for X86. Add support for other targets.
if (Op2VK == TargetTransformInfo::OK_UniformConstantValue && CInt &&
CInt->getValue().isPowerOf2())
Op2VP = TargetTransformInfo::OP_PowerOf2;
ScalarCost = VecTy->getNumElements() *
TTI->getArithmeticInstrCost(Opcode, ScalarTy, Op1VK, Op2VK,
Op1VP, Op2VP);
VecCost = TTI->getArithmeticInstrCost(Opcode, VecTy, Op1VK, Op2VK,
Op1VP, Op2VP);
}
return VecCost - ScalarCost;
}
case Instruction::GetElementPtr: {
TargetTransformInfo::OperandValueKind Op1VK =
TargetTransformInfo::OK_AnyValue;
TargetTransformInfo::OperandValueKind Op2VK =
TargetTransformInfo::OK_UniformConstantValue;
int ScalarCost =
VecTy->getNumElements() *
TTI->getArithmeticInstrCost(Instruction::Add, ScalarTy, Op1VK, Op2VK);
int VecCost =
TTI->getArithmeticInstrCost(Instruction::Add, VecTy, Op1VK, Op2VK);
return VecCost - ScalarCost;
}
case Instruction::Load: {
// Cost of wide load - cost of scalar loads.
int ScalarLdCost = VecTy->getNumElements() *
TTI->getMemoryOpCost(Instruction::Load, ScalarTy, 1, 0);
int VecLdCost = TTI->getMemoryOpCost(Instruction::Load, VecTy, 1, 0);
return VecLdCost - ScalarLdCost;
}
case Instruction::Store: {
// We know that we can merge the stores. Calculate the cost.
int ScalarStCost = VecTy->getNumElements() *
TTI->getMemoryOpCost(Instruction::Store, ScalarTy, 1, 0);
int VecStCost = TTI->getMemoryOpCost(Instruction::Store, VecTy, 1, 0);
return VecStCost - ScalarStCost;
}
case Instruction::Call: {
CallInst *CI = cast<CallInst>(VL0);
Intrinsic::ID ID = getIntrinsicIDForCall(CI, TLI);
// Calculate the cost of the scalar and vector calls.
SmallVector<Type*, 4> ScalarTys, VecTys;
for (unsigned op = 0, opc = CI->getNumArgOperands(); op!= opc; ++op) {
ScalarTys.push_back(CI->getArgOperand(op)->getType());
VecTys.push_back(VectorType::get(CI->getArgOperand(op)->getType(),
VecTy->getNumElements()));
}
int ScalarCallCost = VecTy->getNumElements() *
TTI->getIntrinsicInstrCost(ID, ScalarTy, ScalarTys);
int VecCallCost = TTI->getIntrinsicInstrCost(ID, VecTy, VecTys);
DEBUG(dbgs() << "SLP: Call cost "<< VecCallCost - ScalarCallCost
<< " (" << VecCallCost << "-" << ScalarCallCost << ")"
<< " for " << *CI << "\n");
return VecCallCost - ScalarCallCost;
}
case Instruction::ShuffleVector: {
TargetTransformInfo::OperandValueKind Op1VK =
TargetTransformInfo::OK_AnyValue;
TargetTransformInfo::OperandValueKind Op2VK =
TargetTransformInfo::OK_AnyValue;
int ScalarCost = 0;
int VecCost = 0;
for (unsigned i = 0; i < VL.size(); ++i) {
Instruction *I = cast<Instruction>(VL[i]);
if (!I)
break;
ScalarCost +=
TTI->getArithmeticInstrCost(I->getOpcode(), ScalarTy, Op1VK, Op2VK);
}
// VecCost is equal to sum of the cost of creating 2 vectors
// and the cost of creating shuffle.
Instruction *I0 = cast<Instruction>(VL[0]);
VecCost =
TTI->getArithmeticInstrCost(I0->getOpcode(), VecTy, Op1VK, Op2VK);
Instruction *I1 = cast<Instruction>(VL[1]);
VecCost +=
TTI->getArithmeticInstrCost(I1->getOpcode(), VecTy, Op1VK, Op2VK);
VecCost +=
TTI->getShuffleCost(TargetTransformInfo::SK_Alternate, VecTy, 0);
return VecCost - ScalarCost;
}
default:
llvm_unreachable("Unknown instruction");
}
}
bool BoUpSLP::isFullyVectorizableTinyTree() {
DEBUG(dbgs() << "SLP: Check whether the tree with height " <<
VectorizableTree.size() << " is fully vectorizable .\n");
// We only handle trees of height 2.
if (VectorizableTree.size() != 2)
return false;
// Handle splat and all-constants stores.
if (!VectorizableTree[0].NeedToGather &&
(allConstant(VectorizableTree[1].Scalars) ||
isSplat(VectorizableTree[1].Scalars)))
return true;
// Gathering cost would be too much for tiny trees.
if (VectorizableTree[0].NeedToGather || VectorizableTree[1].NeedToGather)
return false;
return true;
}
int BoUpSLP::getSpillCost() {
// Walk from the bottom of the tree to the top, tracking which values are
// live. When we see a call instruction that is not part of our tree,
// query TTI to see if there is a cost to keeping values live over it
// (for example, if spills and fills are required).
unsigned BundleWidth = VectorizableTree.front().Scalars.size();
int Cost = 0;
SmallPtrSet<Instruction*, 4> LiveValues;
Instruction *PrevInst = nullptr;
for (unsigned N = 0; N < VectorizableTree.size(); ++N) {
Instruction *Inst = dyn_cast<Instruction>(VectorizableTree[N].Scalars[0]);
if (!Inst)
continue;
if (!PrevInst) {
PrevInst = Inst;
continue;
}
DEBUG(
dbgs() << "SLP: #LV: " << LiveValues.size();
for (auto *X : LiveValues)
dbgs() << " " << X->getName();
dbgs() << ", Looking at ";
Inst->dump();
);
// Update LiveValues.
LiveValues.erase(PrevInst);
for (auto &J : PrevInst->operands()) {
if (isa<Instruction>(&*J) && ScalarToTreeEntry.count(&*J))
LiveValues.insert(cast<Instruction>(&*J));
}
// Now find the sequence of instructions between PrevInst and Inst.
BasicBlock::reverse_iterator InstIt(Inst), PrevInstIt(PrevInst);
--PrevInstIt;
while (InstIt != PrevInstIt) {
if (PrevInstIt == PrevInst->getParent()->rend()) {
PrevInstIt = Inst->getParent()->rbegin();
continue;
}
if (isa<CallInst>(&*PrevInstIt) && &*PrevInstIt != PrevInst) {
SmallVector<Type*, 4> V;
for (auto *II : LiveValues)
V.push_back(VectorType::get(II->getType(), BundleWidth));
Cost += TTI->getCostOfKeepingLiveOverCall(V);
}
++PrevInstIt;
}
PrevInst = Inst;
}
DEBUG(dbgs() << "SLP: SpillCost=" << Cost << "\n");
return Cost;
}
int BoUpSLP::getTreeCost() {
int Cost = 0;
DEBUG(dbgs() << "SLP: Calculating cost for tree of size " <<
VectorizableTree.size() << ".\n");
// We only vectorize tiny trees if it is fully vectorizable.
if (VectorizableTree.size() < 3 && !isFullyVectorizableTinyTree()) {
if (VectorizableTree.empty()) {
assert(!ExternalUses.size() && "We should not have any external users");
}
return INT_MAX;
}
unsigned BundleWidth = VectorizableTree[0].Scalars.size();
for (unsigned i = 0, e = VectorizableTree.size(); i != e; ++i) {
int C = getEntryCost(&VectorizableTree[i]);
DEBUG(dbgs() << "SLP: Adding cost " << C << " for bundle that starts with "
<< *VectorizableTree[i].Scalars[0] << " .\n");
Cost += C;
}
SmallSet<Value *, 16> ExtractCostCalculated;
int ExtractCost = 0;
for (UserList::iterator I = ExternalUses.begin(), E = ExternalUses.end();
I != E; ++I) {
// We only add extract cost once for the same scalar.
if (!ExtractCostCalculated.insert(I->Scalar).second)
continue;
// Uses by ephemeral values are free (because the ephemeral value will be
// removed prior to code generation, and so the extraction will be
// removed as well).
if (EphValues.count(I->User))
continue;
VectorType *VecTy = VectorType::get(I->Scalar->getType(), BundleWidth);
ExtractCost += TTI->getVectorInstrCost(Instruction::ExtractElement, VecTy,
I->Lane);
}
Cost += getSpillCost();
DEBUG(dbgs() << "SLP: Total Cost " << Cost + ExtractCost<< ".\n");
return Cost + ExtractCost;
}
int BoUpSLP::getGatherCost(Type *Ty) {
int Cost = 0;
for (unsigned i = 0, e = cast<VectorType>(Ty)->getNumElements(); i < e; ++i)
Cost += TTI->getVectorInstrCost(Instruction::InsertElement, Ty, i);
return Cost;
}
int BoUpSLP::getGatherCost(ArrayRef<Value *> VL) {
// Find the type of the operands in VL.
Type *ScalarTy = VL[0]->getType();
if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
ScalarTy = SI->getValueOperand()->getType();
VectorType *VecTy = VectorType::get(ScalarTy, VL.size());
// Find the cost of inserting/extracting values from the vector.
return getGatherCost(VecTy);
}
Value *BoUpSLP::getPointerOperand(Value *I) {
if (LoadInst *LI = dyn_cast<LoadInst>(I))
return LI->getPointerOperand();
if (StoreInst *SI = dyn_cast<StoreInst>(I))
return SI->getPointerOperand();
return nullptr;
}
unsigned BoUpSLP::getAddressSpaceOperand(Value *I) {
if (LoadInst *L = dyn_cast<LoadInst>(I))
return L->getPointerAddressSpace();
if (StoreInst *S = dyn_cast<StoreInst>(I))
return S->getPointerAddressSpace();
return -1;
}
bool BoUpSLP::isConsecutiveAccess(Value *A, Value *B, const DataLayout &DL) {
Value *PtrA = getPointerOperand(A);
Value *PtrB = getPointerOperand(B);
unsigned ASA = getAddressSpaceOperand(A);
unsigned ASB = getAddressSpaceOperand(B);
// Check that the address spaces match and that the pointers are valid.
if (!PtrA || !PtrB || (ASA != ASB))
return false;
// Make sure that A and B are different pointers of the same type.
if (PtrA == PtrB || PtrA->getType() != PtrB->getType())
return false;
unsigned PtrBitWidth = DL.getPointerSizeInBits(ASA);
Type *Ty = cast<PointerType>(PtrA->getType())->getElementType();
APInt Size(PtrBitWidth, DL.getTypeStoreSize(Ty));
APInt OffsetA(PtrBitWidth, 0), OffsetB(PtrBitWidth, 0);
PtrA = PtrA->stripAndAccumulateInBoundsConstantOffsets(DL, OffsetA);
PtrB = PtrB->stripAndAccumulateInBoundsConstantOffsets(DL, OffsetB);
APInt OffsetDelta = OffsetB - OffsetA;
// Check if they are based on the same pointer. That makes the offsets
// sufficient.
if (PtrA == PtrB)
return OffsetDelta == Size;
// Compute the necessary base pointer delta to have the necessary final delta
// equal to the size.
APInt BaseDelta = Size - OffsetDelta;
// Otherwise compute the distance with SCEV between the base pointers.
const SCEV *PtrSCEVA = SE->getSCEV(PtrA);
const SCEV *PtrSCEVB = SE->getSCEV(PtrB);
const SCEV *C = SE->getConstant(BaseDelta);
const SCEV *X = SE->getAddExpr(PtrSCEVA, C);
return X == PtrSCEVB;
}
// Reorder commutative operations in alternate shuffle if the resulting vectors
// are consecutive loads. This would allow us to vectorize the tree.
// If we have something like-
// load a[0] - load b[0]
// load b[1] + load a[1]
// load a[2] - load b[2]
// load a[3] + load b[3]
// Reordering the second load b[1] load a[1] would allow us to vectorize this
// code.
void BoUpSLP::reorderAltShuffleOperands(ArrayRef<Value *> VL,
SmallVectorImpl<Value *> &Left,
SmallVectorImpl<Value *> &Right) {
const DataLayout &DL = F->getParent()->getDataLayout();
// Push left and right operands of binary operation into Left and Right
for (unsigned i = 0, e = VL.size(); i < e; ++i) {
Left.push_back(cast<Instruction>(VL[i])->getOperand(0));
Right.push_back(cast<Instruction>(VL[i])->getOperand(1));
}
// Reorder if we have a commutative operation and consecutive access
// are on either side of the alternate instructions.
for (unsigned j = 0; j < VL.size() - 1; ++j) {
if (LoadInst *L = dyn_cast<LoadInst>(Left[j])) {
if (LoadInst *L1 = dyn_cast<LoadInst>(Right[j + 1])) {
Instruction *VL1 = cast<Instruction>(VL[j]);
Instruction *VL2 = cast<Instruction>(VL[j + 1]);
if (isConsecutiveAccess(L, L1, DL) && VL1->isCommutative()) {
std::swap(Left[j], Right[j]);
continue;
} else if (isConsecutiveAccess(L, L1, DL) && VL2->isCommutative()) {
std::swap(Left[j + 1], Right[j + 1]);
continue;
}
// else unchanged
}
}
if (LoadInst *L = dyn_cast<LoadInst>(Right[j])) {
if (LoadInst *L1 = dyn_cast<LoadInst>(Left[j + 1])) {
Instruction *VL1 = cast<Instruction>(VL[j]);
Instruction *VL2 = cast<Instruction>(VL[j + 1]);
if (isConsecutiveAccess(L, L1, DL) && VL1->isCommutative()) {
std::swap(Left[j], Right[j]);
continue;
} else if (isConsecutiveAccess(L, L1, DL) && VL2->isCommutative()) {
std::swap(Left[j + 1], Right[j + 1]);
continue;
}
// else unchanged
}
}
}
}
void BoUpSLP::reorderInputsAccordingToOpcode(ArrayRef<Value *> VL,
SmallVectorImpl<Value *> &Left,
SmallVectorImpl<Value *> &Right) {
SmallVector<Value *, 16> OrigLeft, OrigRight;
bool AllSameOpcodeLeft = true;
bool AllSameOpcodeRight = true;
for (unsigned i = 0, e = VL.size(); i != e; ++i) {
Instruction *I = cast<Instruction>(VL[i]);
Value *VLeft = I->getOperand(0);
Value *VRight = I->getOperand(1);
OrigLeft.push_back(VLeft);
OrigRight.push_back(VRight);
Instruction *ILeft = dyn_cast<Instruction>(VLeft);
Instruction *IRight = dyn_cast<Instruction>(VRight);
// Check whether all operands on one side have the same opcode. In this case
// we want to preserve the original order and not make things worse by
// reordering.
if (i && AllSameOpcodeLeft && ILeft) {
if (Instruction *PLeft = dyn_cast<Instruction>(OrigLeft[i - 1])) {
if (PLeft->getOpcode() != ILeft->getOpcode())
AllSameOpcodeLeft = false;
} else
AllSameOpcodeLeft = false;
}
if (i && AllSameOpcodeRight && IRight) {
if (Instruction *PRight = dyn_cast<Instruction>(OrigRight[i - 1])) {
if (PRight->getOpcode() != IRight->getOpcode())
AllSameOpcodeRight = false;
} else
AllSameOpcodeRight = false;
}
// Sort two opcodes. In the code below we try to preserve the ability to use
// broadcast of values instead of individual inserts.
// vl1 = load
// vl2 = phi
// vr1 = load
// vr2 = vr2
// = vl1 x vr1
// = vl2 x vr2
// If we just sorted according to opcode we would leave the first line in
// tact but we would swap vl2 with vr2 because opcode(phi) > opcode(load).
// = vl1 x vr1
// = vr2 x vl2
// Because vr2 and vr1 are from the same load we loose the opportunity of a
// broadcast for the packed right side in the backend: we have [vr1, vl2]
// instead of [vr1, vr2=vr1].
if (ILeft && IRight) {
if (!i && ILeft->getOpcode() > IRight->getOpcode()) {
Left.push_back(IRight);
Right.push_back(ILeft);
} else if (i && ILeft->getOpcode() > IRight->getOpcode() &&
Right[i - 1] != IRight) {
// Try not to destroy a broad cast for no apparent benefit.
Left.push_back(IRight);
Right.push_back(ILeft);
} else if (i && ILeft->getOpcode() == IRight->getOpcode() &&
Right[i - 1] == ILeft) {
// Try preserve broadcasts.
Left.push_back(IRight);
Right.push_back(ILeft);
} else if (i && ILeft->getOpcode() == IRight->getOpcode() &&
Left[i - 1] == IRight) {
// Try preserve broadcasts.
Left.push_back(IRight);
Right.push_back(ILeft);
} else {
Left.push_back(ILeft);
Right.push_back(IRight);
}
continue;
}
// One opcode, put the instruction on the right.
if (ILeft) {
Left.push_back(VRight);
Right.push_back(ILeft);
continue;
}
Left.push_back(VLeft);
Right.push_back(VRight);
}
bool LeftBroadcast = isSplat(Left);
bool RightBroadcast = isSplat(Right);
// If operands end up being broadcast return this operand order.
if (LeftBroadcast || RightBroadcast)
return;
// Don't reorder if the operands where good to begin.
if (AllSameOpcodeRight || AllSameOpcodeLeft) {
Left = OrigLeft;
Right = OrigRight;
}
const DataLayout &DL = F->getParent()->getDataLayout();
// Finally check if we can get longer vectorizable chain by reordering
// without breaking the good operand order detected above.
// E.g. If we have something like-
// load a[0] load b[0]
// load b[1] load a[1]
// load a[2] load b[2]
// load a[3] load b[3]
// Reordering the second load b[1] load a[1] would allow us to vectorize
// this code and we still retain AllSameOpcode property.
// FIXME: This load reordering might break AllSameOpcode in some rare cases
// such as-
// add a[0],c[0] load b[0]
// add a[1],c[2] load b[1]
// b[2] load b[2]
// add a[3],c[3] load b[3]
for (unsigned j = 0; j < VL.size() - 1; ++j) {
if (LoadInst *L = dyn_cast<LoadInst>(Left[j])) {
if (LoadInst *L1 = dyn_cast<LoadInst>(Right[j + 1])) {
if (isConsecutiveAccess(L, L1, DL)) {
std::swap(Left[j + 1], Right[j + 1]);
continue;
}
}
}
if (LoadInst *L = dyn_cast<LoadInst>(Right[j])) {
if (LoadInst *L1 = dyn_cast<LoadInst>(Left[j + 1])) {
if (isConsecutiveAccess(L, L1, DL)) {
std::swap(Left[j + 1], Right[j + 1]);
continue;
}
}
}
// else unchanged
}
}
void BoUpSLP::setInsertPointAfterBundle(ArrayRef<Value *> VL) {
Instruction *VL0 = cast<Instruction>(VL[0]);
BasicBlock::iterator NextInst = VL0;
++NextInst;
Builder.SetInsertPoint(VL0->getParent(), NextInst);
Builder.SetCurrentDebugLocation(VL0->getDebugLoc());
}
Value *BoUpSLP::Gather(ArrayRef<Value *> VL, VectorType *Ty) {
Value *Vec = UndefValue::get(Ty);
// Generate the 'InsertElement' instruction.
for (unsigned i = 0; i < Ty->getNumElements(); ++i) {
Vec = Builder.CreateInsertElement(Vec, VL[i], Builder.getInt32(i));
if (Instruction *Insrt = dyn_cast<Instruction>(Vec)) {
GatherSeq.insert(Insrt);
CSEBlocks.insert(Insrt->getParent());
// Add to our 'need-to-extract' list.
if (ScalarToTreeEntry.count(VL[i])) {
int Idx = ScalarToTreeEntry[VL[i]];
TreeEntry *E = &VectorizableTree[Idx];
// Find which lane we need to extract.
int FoundLane = -1;
for (unsigned Lane = 0, LE = VL.size(); Lane != LE; ++Lane) {
// Is this the lane of the scalar that we are looking for ?
if (E->Scalars[Lane] == VL[i]) {
FoundLane = Lane;
break;
}
}
assert(FoundLane >= 0 && "Could not find the correct lane");
ExternalUses.push_back(ExternalUser(VL[i], Insrt, FoundLane));
}
}
}
return Vec;
}
Value *BoUpSLP::alreadyVectorized(ArrayRef<Value *> VL) const {
SmallDenseMap<Value*, int>::const_iterator Entry
= ScalarToTreeEntry.find(VL[0]);
if (Entry != ScalarToTreeEntry.end()) {
int Idx = Entry->second;
const TreeEntry *En = &VectorizableTree[Idx];
if (En->isSame(VL) && En->VectorizedValue)
return En->VectorizedValue;
}
return nullptr;
}
Value *BoUpSLP::vectorizeTree(ArrayRef<Value *> VL) {
if (ScalarToTreeEntry.count(VL[0])) {
int Idx = ScalarToTreeEntry[VL[0]];
TreeEntry *E = &VectorizableTree[Idx];
if (E->isSame(VL))
return vectorizeTree(E);
}
Type *ScalarTy = VL[0]->getType();
if (StoreInst *SI = dyn_cast<StoreInst>(VL[0]))
ScalarTy = SI->getValueOperand()->getType();
VectorType *VecTy = VectorType::get(ScalarTy, VL.size());
return Gather(VL, VecTy);
}
Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
IRBuilder<>::InsertPointGuard Guard(Builder);
if (E->VectorizedValue) {
DEBUG(dbgs() << "SLP: Diamond merged for " << *E->Scalars[0] << ".\n");
return E->VectorizedValue;
}
Instruction *VL0 = cast<Instruction>(E->Scalars[0]);
Type *ScalarTy = VL0->getType();
if (StoreInst *SI = dyn_cast<StoreInst>(VL0))
ScalarTy = SI->getValueOperand()->getType();
VectorType *VecTy = VectorType::get(ScalarTy, E->Scalars.size());
if (E->NeedToGather) {
setInsertPointAfterBundle(E->Scalars);
return Gather(E->Scalars, VecTy);
}
const DataLayout &DL = F->getParent()->getDataLayout();
unsigned Opcode = getSameOpcode(E->Scalars);
switch (Opcode) {
case Instruction::PHI: {
PHINode *PH = dyn_cast<PHINode>(VL0);
Builder.SetInsertPoint(PH->getParent()->getFirstNonPHI());
Builder.SetCurrentDebugLocation(PH->getDebugLoc());
PHINode *NewPhi = Builder.CreatePHI(VecTy, PH->getNumIncomingValues());
E->VectorizedValue = NewPhi;
// PHINodes may have multiple entries from the same block. We want to
// visit every block once.
SmallSet<BasicBlock*, 4> VisitedBBs;
for (unsigned i = 0, e = PH->getNumIncomingValues(); i < e; ++i) {
ValueList Operands;
BasicBlock *IBB = PH->getIncomingBlock(i);
if (!VisitedBBs.insert(IBB).second) {
NewPhi->addIncoming(NewPhi->getIncomingValueForBlock(IBB), IBB);
continue;
}
// Prepare the operand vector.
for (Value *V : E->Scalars)
Operands.push_back(cast<PHINode>(V)->getIncomingValueForBlock(IBB));
Builder.SetInsertPoint(IBB->getTerminator());
Builder.SetCurrentDebugLocation(PH->getDebugLoc());
Value *Vec = vectorizeTree(Operands);
NewPhi->addIncoming(Vec, IBB);
}
assert(NewPhi->getNumIncomingValues() == PH->getNumIncomingValues() &&
"Invalid number of incoming values");
return NewPhi;
}
case Instruction::ExtractElement: {
if (CanReuseExtract(E->Scalars)) {
Value *V = VL0->getOperand(0);
E->VectorizedValue = V;
return V;
}
return Gather(E->Scalars, VecTy);
}
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::FPToUI:
case Instruction::FPToSI:
case Instruction::FPExt:
case Instruction::PtrToInt:
case Instruction::IntToPtr:
case Instruction::SIToFP:
case Instruction::UIToFP:
case Instruction::Trunc:
case Instruction::FPTrunc:
case Instruction::BitCast: {
ValueList INVL;
for (Value *V : E->Scalars)
INVL.push_back(cast<Instruction>(V)->getOperand(0));
setInsertPointAfterBundle(E->Scalars);
Value *InVec = vectorizeTree(INVL);
if (Value *V = alreadyVectorized(E->Scalars))
return V;
CastInst *CI = dyn_cast<CastInst>(VL0);
Value *V = Builder.CreateCast(CI->getOpcode(), InVec, VecTy);
E->VectorizedValue = V;
++NumVectorInstructions;
return V;
}
case Instruction::FCmp:
case Instruction::ICmp: {
ValueList LHSV, RHSV;
for (Value *V : E->Scalars) {
LHSV.push_back(cast<Instruction>(V)->getOperand(0));
RHSV.push_back(cast<Instruction>(V)->getOperand(1));
}
setInsertPointAfterBundle(E->Scalars);
Value *L = vectorizeTree(LHSV);
Value *R = vectorizeTree(RHSV);
if (Value *V = alreadyVectorized(E->Scalars))
return V;
CmpInst::Predicate P0 = cast<CmpInst>(VL0)->getPredicate();
Value *V;
if (Opcode == Instruction::FCmp)
V = Builder.CreateFCmp(P0, L, R);
else
V = Builder.CreateICmp(P0, L, R);
E->VectorizedValue = V;
++NumVectorInstructions;
return V;
}
case Instruction::Select: {
ValueList TrueVec, FalseVec, CondVec;
for (Value *V : E->Scalars) {
CondVec.push_back(cast<Instruction>(V)->getOperand(0));
TrueVec.push_back(cast<Instruction>(V)->getOperand(1));
FalseVec.push_back(cast<Instruction>(V)->getOperand(2));
}
setInsertPointAfterBundle(E->Scalars);
Value *Cond = vectorizeTree(CondVec);
Value *True = vectorizeTree(TrueVec);
Value *False = vectorizeTree(FalseVec);
if (Value *V = alreadyVectorized(E->Scalars))
return V;
Value *V = Builder.CreateSelect(Cond, True, False);
E->VectorizedValue = V;
++NumVectorInstructions;
return V;
}
case Instruction::Add:
case Instruction::FAdd:
case Instruction::Sub:
case Instruction::FSub:
case Instruction::Mul:
case Instruction::FMul:
case Instruction::UDiv:
case Instruction::SDiv:
case Instruction::FDiv:
case Instruction::URem:
case Instruction::SRem:
case Instruction::FRem:
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
case Instruction::And:
case Instruction::Or:
case Instruction::Xor: {
ValueList LHSVL, RHSVL;
if (isa<BinaryOperator>(VL0) && VL0->isCommutative())
reorderInputsAccordingToOpcode(E->Scalars, LHSVL, RHSVL);
else
for (Value *V : E->Scalars) {
LHSVL.push_back(cast<Instruction>(V)->getOperand(0));
RHSVL.push_back(cast<Instruction>(V)->getOperand(1));
}
setInsertPointAfterBundle(E->Scalars);
Value *LHS = vectorizeTree(LHSVL);
Value *RHS = vectorizeTree(RHSVL);
if (LHS == RHS && isa<Instruction>(LHS)) {
assert((VL0->getOperand(0) == VL0->getOperand(1)) && "Invalid order");
}
if (Value *V = alreadyVectorized(E->Scalars))
return V;
BinaryOperator *BinOp = cast<BinaryOperator>(VL0);
Value *V = Builder.CreateBinOp(BinOp->getOpcode(), LHS, RHS);
E->VectorizedValue = V;
propagateIRFlags(E->VectorizedValue, E->Scalars);
++NumVectorInstructions;
if (Instruction *I = dyn_cast<Instruction>(V))
return propagateMetadata(I, E->Scalars);
return V;
}
case Instruction::Load: {
// Loads are inserted at the head of the tree because we don't want to
// sink them all the way down past store instructions.
setInsertPointAfterBundle(E->Scalars);
LoadInst *LI = cast<LoadInst>(VL0);
Type *ScalarLoadTy = LI->getType();
unsigned AS = LI->getPointerAddressSpace();
Value *VecPtr = Builder.CreateBitCast(LI->getPointerOperand(),
VecTy->getPointerTo(AS));
// The pointer operand uses an in-tree scalar so we add the new BitCast to
// ExternalUses list to make sure that an extract will be generated in the
// future.
if (ScalarToTreeEntry.count(LI->getPointerOperand()))
ExternalUses.push_back(
ExternalUser(LI->getPointerOperand(), cast<User>(VecPtr), 0));
unsigned Alignment = LI->getAlignment();
LI = Builder.CreateLoad(VecPtr);
if (!Alignment) {
Alignment = DL.getABITypeAlignment(ScalarLoadTy);
}
LI->setAlignment(Alignment);
E->VectorizedValue = LI;
++NumVectorInstructions;
return propagateMetadata(LI, E->Scalars);
}
case Instruction::Store: {
StoreInst *SI = cast<StoreInst>(VL0);
unsigned Alignment = SI->getAlignment();
unsigned AS = SI->getPointerAddressSpace();
ValueList ValueOp;
for (Value *V : E->Scalars)
ValueOp.push_back(cast<StoreInst>(V)->getValueOperand());
setInsertPointAfterBundle(E->Scalars);
Value *VecValue = vectorizeTree(ValueOp);
Value *VecPtr = Builder.CreateBitCast(SI->getPointerOperand(),
VecTy->getPointerTo(AS));
StoreInst *S = Builder.CreateStore(VecValue, VecPtr);
// The pointer operand uses an in-tree scalar so we add the new BitCast to
// ExternalUses list to make sure that an extract will be generated in the
// future.
if (ScalarToTreeEntry.count(SI->getPointerOperand()))
ExternalUses.push_back(
ExternalUser(SI->getPointerOperand(), cast<User>(VecPtr), 0));
if (!Alignment) {
Alignment = DL.getABITypeAlignment(SI->getValueOperand()->getType());
}
S->setAlignment(Alignment);
E->VectorizedValue = S;
++NumVectorInstructions;
return propagateMetadata(S, E->Scalars);
}
case Instruction::GetElementPtr: {
setInsertPointAfterBundle(E->Scalars);
ValueList Op0VL;
for (Value *V : E->Scalars)
Op0VL.push_back(cast<GetElementPtrInst>(V)->getOperand(0));
Value *Op0 = vectorizeTree(Op0VL);
std::vector<Value *> OpVecs;
for (int j = 1, e = cast<GetElementPtrInst>(VL0)->getNumOperands(); j < e;
++j) {
ValueList OpVL;
for (Value *V : E->Scalars)
OpVL.push_back(cast<GetElementPtrInst>(V)->getOperand(j));
Value *OpVec = vectorizeTree(OpVL);
OpVecs.push_back(OpVec);
}
Value *V = Builder.CreateGEP(
cast<GetElementPtrInst>(VL0)->getSourceElementType(), Op0, OpVecs);
E->VectorizedValue = V;
++NumVectorInstructions;
if (Instruction *I = dyn_cast<Instruction>(V))
return propagateMetadata(I, E->Scalars);
return V;
}
case Instruction::Call: {
CallInst *CI = cast<CallInst>(VL0);
setInsertPointAfterBundle(E->Scalars);
Function *FI;
Intrinsic::ID IID = Intrinsic::not_intrinsic;
Value *ScalarArg = nullptr;
if (CI && (FI = CI->getCalledFunction())) {
IID = FI->getIntrinsicID();
}
std::vector<Value *> OpVecs;
for (int j = 0, e = CI->getNumArgOperands(); j < e; ++j) {
ValueList OpVL;
// ctlz,cttz and powi are special intrinsics whose second argument is
// a scalar. This argument should not be vectorized.
if (hasVectorInstrinsicScalarOpd(IID, 1) && j == 1) {
CallInst *CEI = cast<CallInst>(E->Scalars[0]);
ScalarArg = CEI->getArgOperand(j);
OpVecs.push_back(CEI->getArgOperand(j));
continue;
}
for (Value *V : E->Scalars) {
CallInst *CEI = cast<CallInst>(V);
OpVL.push_back(CEI->getArgOperand(j));
}
Value *OpVec = vectorizeTree(OpVL);
DEBUG(dbgs() << "SLP: OpVec[" << j << "]: " << *OpVec << "\n");
OpVecs.push_back(OpVec);
}
Module *M = F->getParent();
Intrinsic::ID ID = getIntrinsicIDForCall(CI, TLI);
Type *Tys[] = { VectorType::get(CI->getType(), E->Scalars.size()) };
Function *CF = Intrinsic::getDeclaration(M, ID, Tys);
Value *V = Builder.CreateCall(CF, OpVecs);
// The scalar argument uses an in-tree scalar so we add the new vectorized
// call to ExternalUses list to make sure that an extract will be
// generated in the future.
if (ScalarArg && ScalarToTreeEntry.count(ScalarArg))
ExternalUses.push_back(ExternalUser(ScalarArg, cast<User>(V), 0));
E->VectorizedValue = V;
++NumVectorInstructions;
return V;
}
case Instruction::ShuffleVector: {
ValueList LHSVL, RHSVL;
assert(isa<BinaryOperator>(VL0) && "Invalid Shuffle Vector Operand");
reorderAltShuffleOperands(E->Scalars, LHSVL, RHSVL);
setInsertPointAfterBundle(E->Scalars);
Value *LHS = vectorizeTree(LHSVL);
Value *RHS = vectorizeTree(RHSVL);
if (Value *V = alreadyVectorized(E->Scalars))
return V;
// Create a vector of LHS op1 RHS
BinaryOperator *BinOp0 = cast<BinaryOperator>(VL0);
Value *V0 = Builder.CreateBinOp(BinOp0->getOpcode(), LHS, RHS);
// Create a vector of LHS op2 RHS
Instruction *VL1 = cast<Instruction>(E->Scalars[1]);
BinaryOperator *BinOp1 = cast<BinaryOperator>(VL1);
Value *V1 = Builder.CreateBinOp(BinOp1->getOpcode(), LHS, RHS);
// Create shuffle to take alternate operations from the vector.
// Also, gather up odd and even scalar ops to propagate IR flags to
// each vector operation.
ValueList OddScalars, EvenScalars;
unsigned e = E->Scalars.size();
SmallVector<Constant *, 8> Mask(e);
for (unsigned i = 0; i < e; ++i) {
if (i & 1) {
Mask[i] = Builder.getInt32(e + i);
OddScalars.push_back(E->Scalars[i]);
} else {
Mask[i] = Builder.getInt32(i);
EvenScalars.push_back(E->Scalars[i]);
}
}
Value *ShuffleMask = ConstantVector::get(Mask);
propagateIRFlags(V0, EvenScalars);
propagateIRFlags(V1, OddScalars);
Value *V = Builder.CreateShuffleVector(V0, V1, ShuffleMask);
E->VectorizedValue = V;
++NumVectorInstructions;
if (Instruction *I = dyn_cast<Instruction>(V))
return propagateMetadata(I, E->Scalars);
return V;
}
default:
llvm_unreachable("unknown inst");
}
return nullptr;
}
Value *BoUpSLP::vectorizeTree() {
// All blocks must be scheduled before any instructions are inserted.
for (auto &BSIter : BlocksSchedules) {
scheduleBlock(BSIter.second.get());
}
Builder.SetInsertPoint(F->getEntryBlock().begin());
vectorizeTree(&VectorizableTree[0]);
DEBUG(dbgs() << "SLP: Extracting " << ExternalUses.size() << " values .\n");
// Extract all of the elements with the external uses.
for (UserList::iterator it = ExternalUses.begin(), e = ExternalUses.end();
it != e; ++it) {
Value *Scalar = it->Scalar;
llvm::User *User = it->User;
// Skip users that we already RAUW. This happens when one instruction
// has multiple uses of the same value.
if (std::find(Scalar->user_begin(), Scalar->user_end(), User) ==
Scalar->user_end())
continue;
assert(ScalarToTreeEntry.count(Scalar) && "Invalid scalar");
int Idx = ScalarToTreeEntry[Scalar];
TreeEntry *E = &VectorizableTree[Idx];
assert(!E->NeedToGather && "Extracting from a gather list");
Value *Vec = E->VectorizedValue;
assert(Vec && "Can't find vectorizable value");
Value *Lane = Builder.getInt32(it->Lane);
// Generate extracts for out-of-tree users.
// Find the insertion point for the extractelement lane.
if (isa<Instruction>(Vec)){
if (PHINode *PH = dyn_cast<PHINode>(User)) {
for (int i = 0, e = PH->getNumIncomingValues(); i != e; ++i) {
if (PH->getIncomingValue(i) == Scalar) {
Builder.SetInsertPoint(PH->getIncomingBlock(i)->getTerminator());
Value *Ex = Builder.CreateExtractElement(Vec, Lane);
CSEBlocks.insert(PH->getIncomingBlock(i));
PH->setOperand(i, Ex);
}
}
} else {
Builder.SetInsertPoint(cast<Instruction>(User));
Value *Ex = Builder.CreateExtractElement(Vec, Lane);
CSEBlocks.insert(cast<Instruction>(User)->getParent());
User->replaceUsesOfWith(Scalar, Ex);
}
} else {
Builder.SetInsertPoint(F->getEntryBlock().begin());
Value *Ex = Builder.CreateExtractElement(Vec, Lane);
CSEBlocks.insert(&F->getEntryBlock());
User->replaceUsesOfWith(Scalar, Ex);
}
DEBUG(dbgs() << "SLP: Replaced:" << *User << ".\n");
}
// For each vectorized value:
for (int EIdx = 0, EE = VectorizableTree.size(); EIdx < EE; ++EIdx) {
TreeEntry *Entry = &VectorizableTree[EIdx];
// For each lane:
for (int Lane = 0, LE = Entry->Scalars.size(); Lane != LE; ++Lane) {
Value *Scalar = Entry->Scalars[Lane];
// No need to handle users of gathered values.
if (Entry->NeedToGather)
continue;
assert(Entry->VectorizedValue && "Can't find vectorizable value");
Type *Ty = Scalar->getType();
if (!Ty->isVoidTy()) {
#ifndef NDEBUG
for (User *U : Scalar->users()) {
DEBUG(dbgs() << "SLP: \tvalidating user:" << *U << ".\n");
assert((ScalarToTreeEntry.count(U) ||
// It is legal to replace users in the ignorelist by undef.
(std::find(UserIgnoreList.begin(), UserIgnoreList.end(), U) !=
UserIgnoreList.end())) &&
"Replacing out-of-tree value with undef");
}
#endif
Value *Undef = UndefValue::get(Ty);
Scalar->replaceAllUsesWith(Undef);
}
DEBUG(dbgs() << "SLP: \tErasing scalar:" << *Scalar << ".\n");
eraseInstruction(cast<Instruction>(Scalar));
}
}
Builder.ClearInsertionPoint();
return VectorizableTree[0].VectorizedValue;
}
void BoUpSLP::optimizeGatherSequence() {
DEBUG(dbgs() << "SLP: Optimizing " << GatherSeq.size()
<< " gather sequences instructions.\n");
// LICM InsertElementInst sequences.
for (SetVector<Instruction *>::iterator it = GatherSeq.begin(),
e = GatherSeq.end(); it != e; ++it) {
InsertElementInst *Insert = dyn_cast<InsertElementInst>(*it);
if (!Insert)
continue;
// Check if this block is inside a loop.
Loop *L = LI->getLoopFor(Insert->getParent());
if (!L)
continue;
// Check if it has a preheader.
BasicBlock *PreHeader = L->getLoopPreheader();
if (!PreHeader)
continue;
// If the vector or the element that we insert into it are
// instructions that are defined in this basic block then we can't
// hoist this instruction.
Instruction *CurrVec = dyn_cast<Instruction>(Insert->getOperand(0));
Instruction *NewElem = dyn_cast<Instruction>(Insert->getOperand(1));
if (CurrVec && L->contains(CurrVec))
continue;
if (NewElem && L->contains(NewElem))
continue;
// We can hoist this instruction. Move it to the pre-header.
Insert->moveBefore(PreHeader->getTerminator());
}
// Make a list of all reachable blocks in our CSE queue.
SmallVector<const DomTreeNode *, 8> CSEWorkList;
CSEWorkList.reserve(CSEBlocks.size());
for (BasicBlock *BB : CSEBlocks)
if (DomTreeNode *N = DT->getNode(BB)) {
assert(DT->isReachableFromEntry(N));
CSEWorkList.push_back(N);
}
// Sort blocks by domination. This ensures we visit a block after all blocks
// dominating it are visited.
std::stable_sort(CSEWorkList.begin(), CSEWorkList.end(),
[this](const DomTreeNode *A, const DomTreeNode *B) {
return DT->properlyDominates(A, B);
});
// Perform O(N^2) search over the gather sequences and merge identical
// instructions. TODO: We can further optimize this scan if we split the
// instructions into different buckets based on the insert lane.
SmallVector<Instruction *, 16> Visited;
for (auto I = CSEWorkList.begin(), E = CSEWorkList.end(); I != E; ++I) {
assert((I == CSEWorkList.begin() || !DT->dominates(*I, *std::prev(I))) &&
"Worklist not sorted properly!");
BasicBlock *BB = (*I)->getBlock();
// For all instructions in blocks containing gather sequences:
for (BasicBlock::iterator it = BB->begin(), e = BB->end(); it != e;) {
Instruction *In = it++;
if (!isa<InsertElementInst>(In) && !isa<ExtractElementInst>(In))
continue;
// Check if we can replace this instruction with any of the
// visited instructions.
for (SmallVectorImpl<Instruction *>::iterator v = Visited.begin(),
ve = Visited.end();
v != ve; ++v) {
if (In->isIdenticalTo(*v) &&
DT->dominates((*v)->getParent(), In->getParent())) {
In->replaceAllUsesWith(*v);
eraseInstruction(In);
In = nullptr;
break;
}
}
if (In) {
assert(std::find(Visited.begin(), Visited.end(), In) == Visited.end());
Visited.push_back(In);
}
}
}
CSEBlocks.clear();
GatherSeq.clear();
}
// Groups the instructions to a bundle (which is then a single scheduling entity)
// and schedules instructions until the bundle gets ready.
bool BoUpSLP::BlockScheduling::tryScheduleBundle(ArrayRef<Value *> VL,
BoUpSLP *SLP) {
if (isa<PHINode>(VL[0]))
return true;
// Initialize the instruction bundle.
Instruction *OldScheduleEnd = ScheduleEnd;
ScheduleData *PrevInBundle = nullptr;
ScheduleData *Bundle = nullptr;
bool ReSchedule = false;
DEBUG(dbgs() << "SLP: bundle: " << *VL[0] << "\n");
for (Value *V : VL) {
extendSchedulingRegion(V);
ScheduleData *BundleMember = getScheduleData(V);
assert(BundleMember &&
"no ScheduleData for bundle member (maybe not in same basic block)");
if (BundleMember->IsScheduled) {
// A bundle member was scheduled as single instruction before and now
// needs to be scheduled as part of the bundle. We just get rid of the
// existing schedule.
DEBUG(dbgs() << "SLP: reset schedule because " << *BundleMember
<< " was already scheduled\n");
ReSchedule = true;
}
assert(BundleMember->isSchedulingEntity() &&
"bundle member already part of other bundle");
if (PrevInBundle) {
PrevInBundle->NextInBundle = BundleMember;
} else {
Bundle = BundleMember;
}
BundleMember->UnscheduledDepsInBundle = 0;
Bundle->UnscheduledDepsInBundle += BundleMember->UnscheduledDeps;
// Group the instructions to a bundle.
BundleMember->FirstInBundle = Bundle;
PrevInBundle = BundleMember;
}
if (ScheduleEnd != OldScheduleEnd) {
// The scheduling region got new instructions at the lower end (or it is a
// new region for the first bundle). This makes it necessary to
// recalculate all dependencies.
// It is seldom that this needs to be done a second time after adding the
// initial bundle to the region.
for (auto *I = ScheduleStart; I != ScheduleEnd; I = I->getNextNode()) {
ScheduleData *SD = getScheduleData(I);
SD->clearDependencies();
}
ReSchedule = true;
}
if (ReSchedule) {
resetSchedule();
initialFillReadyList(ReadyInsts);
}
DEBUG(dbgs() << "SLP: try schedule bundle " << *Bundle << " in block "
<< BB->getName() << "\n");
calculateDependencies(Bundle, true, SLP);
// Now try to schedule the new bundle. As soon as the bundle is "ready" it
// means that there are no cyclic dependencies and we can schedule it.
// Note that's important that we don't "schedule" the bundle yet (see
// cancelScheduling).
while (!Bundle->isReady() && !ReadyInsts.empty()) {
ScheduleData *pickedSD = ReadyInsts.back();
ReadyInsts.pop_back();
if (pickedSD->isSchedulingEntity() && pickedSD->isReady()) {
schedule(pickedSD, ReadyInsts);
}
}
return Bundle->isReady();
}
void BoUpSLP::BlockScheduling::cancelScheduling(ArrayRef<Value *> VL) {
if (isa<PHINode>(VL[0]))
return;
ScheduleData *Bundle = getScheduleData(VL[0]);
DEBUG(dbgs() << "SLP: cancel scheduling of " << *Bundle << "\n");
assert(!Bundle->IsScheduled &&
"Can't cancel bundle which is already scheduled");
assert(Bundle->isSchedulingEntity() && Bundle->isPartOfBundle() &&
"tried to unbundle something which is not a bundle");
// Un-bundle: make single instructions out of the bundle.
ScheduleData *BundleMember = Bundle;
while (BundleMember) {
assert(BundleMember->FirstInBundle == Bundle && "corrupt bundle links");
BundleMember->FirstInBundle = BundleMember;
ScheduleData *Next = BundleMember->NextInBundle;
BundleMember->NextInBundle = nullptr;
BundleMember->UnscheduledDepsInBundle = BundleMember->UnscheduledDeps;
if (BundleMember->UnscheduledDepsInBundle == 0) {
ReadyInsts.insert(BundleMember);
}
BundleMember = Next;
}
}
void BoUpSLP::BlockScheduling::extendSchedulingRegion(Value *V) {
if (getScheduleData(V))
return;
Instruction *I = dyn_cast<Instruction>(V);
assert(I && "bundle member must be an instruction");
assert(!isa<PHINode>(I) && "phi nodes don't need to be scheduled");
if (!ScheduleStart) {
// It's the first instruction in the new region.
initScheduleData(I, I->getNextNode(), nullptr, nullptr);
ScheduleStart = I;
ScheduleEnd = I->getNextNode();
assert(ScheduleEnd && "tried to vectorize a TerminatorInst?");
DEBUG(dbgs() << "SLP: initialize schedule region to " << *I << "\n");
return;
}
// Search up and down at the same time, because we don't know if the new
// instruction is above or below the existing scheduling region.
BasicBlock::reverse_iterator UpIter(ScheduleStart);
BasicBlock::reverse_iterator UpperEnd = BB->rend();
BasicBlock::iterator DownIter(ScheduleEnd);
BasicBlock::iterator LowerEnd = BB->end();
for (;;) {
if (UpIter != UpperEnd) {
if (&*UpIter == I) {
initScheduleData(I, ScheduleStart, nullptr, FirstLoadStoreInRegion);
ScheduleStart = I;
DEBUG(dbgs() << "SLP: extend schedule region start to " << *I << "\n");
return;
}
UpIter++;
}
if (DownIter != LowerEnd) {
if (&*DownIter == I) {
initScheduleData(ScheduleEnd, I->getNextNode(), LastLoadStoreInRegion,
nullptr);
ScheduleEnd = I->getNextNode();
assert(ScheduleEnd && "tried to vectorize a TerminatorInst?");
DEBUG(dbgs() << "SLP: extend schedule region end to " << *I << "\n");
return;
}
DownIter++;
}
assert((UpIter != UpperEnd || DownIter != LowerEnd) &&
"instruction not found in block");
}
}
void BoUpSLP::BlockScheduling::initScheduleData(Instruction *FromI,
Instruction *ToI,
ScheduleData *PrevLoadStore,
ScheduleData *NextLoadStore) {
ScheduleData *CurrentLoadStore = PrevLoadStore;
for (Instruction *I = FromI; I != ToI; I = I->getNextNode()) {
ScheduleData *SD = ScheduleDataMap[I];
if (!SD) {
// Allocate a new ScheduleData for the instruction.
if (ChunkPos >= ChunkSize) {
ScheduleDataChunks.push_back(
llvm::make_unique<ScheduleData[]>(ChunkSize));
ChunkPos = 0;
}
SD = &(ScheduleDataChunks.back()[ChunkPos++]);
ScheduleDataMap[I] = SD;
SD->Inst = I;
}
assert(!isInSchedulingRegion(SD) &&
"new ScheduleData already in scheduling region");
SD->init(SchedulingRegionID);
if (I->mayReadOrWriteMemory()) {
// Update the linked list of memory accessing instructions.
if (CurrentLoadStore) {
CurrentLoadStore->NextLoadStore = SD;
} else {
FirstLoadStoreInRegion = SD;
}
CurrentLoadStore = SD;
}
}
if (NextLoadStore) {
if (CurrentLoadStore)
CurrentLoadStore->NextLoadStore = NextLoadStore;
} else {
LastLoadStoreInRegion = CurrentLoadStore;
}
}
void BoUpSLP::BlockScheduling::calculateDependencies(ScheduleData *SD,
bool InsertInReadyList,
BoUpSLP *SLP) {
assert(SD->isSchedulingEntity());
SmallVector<ScheduleData *, 10> WorkList;
WorkList.push_back(SD);
while (!WorkList.empty()) {
ScheduleData *SD = WorkList.back();
WorkList.pop_back();
ScheduleData *BundleMember = SD;
while (BundleMember) {
assert(isInSchedulingRegion(BundleMember));
if (!BundleMember->hasValidDependencies()) {
DEBUG(dbgs() << "SLP: update deps of " << *BundleMember << "\n");
BundleMember->Dependencies = 0;
BundleMember->resetUnscheduledDeps();
// Handle def-use chain dependencies.
for (User *U : BundleMember->Inst->users()) {
if (isa<Instruction>(U)) {
ScheduleData *UseSD = getScheduleData(U);
if (UseSD && isInSchedulingRegion(UseSD->FirstInBundle)) {
BundleMember->Dependencies++;
ScheduleData *DestBundle = UseSD->FirstInBundle;
if (!DestBundle->IsScheduled) {
BundleMember->incrementUnscheduledDeps(1);
}
if (!DestBundle->hasValidDependencies()) {
WorkList.push_back(DestBundle);
}
}
} else {
// I'm not sure if this can ever happen. But we need to be safe.
// This lets the instruction/bundle never be scheduled and eventally
// disable vectorization.
BundleMember->Dependencies++;
BundleMember->incrementUnscheduledDeps(1);
}
}
// Handle the memory dependencies.
ScheduleData *DepDest = BundleMember->NextLoadStore;
if (DepDest) {
Instruction *SrcInst = BundleMember->Inst;
MemoryLocation SrcLoc = getLocation(SrcInst, SLP->AA);
bool SrcMayWrite = BundleMember->Inst->mayWriteToMemory();
unsigned numAliased = 0;
unsigned DistToSrc = 1;
while (DepDest) {
assert(isInSchedulingRegion(DepDest));
// We have two limits to reduce the complexity:
// 1) AliasedCheckLimit: It's a small limit to reduce calls to
// SLP->isAliased (which is the expensive part in this loop).
// 2) MaxMemDepDistance: It's for very large blocks and it aborts
// the whole loop (even if the loop is fast, it's quadratic).
// It's important for the loop break condition (see below) to
// check this limit even between two read-only instructions.
if (DistToSrc >= MaxMemDepDistance ||
((SrcMayWrite || DepDest->Inst->mayWriteToMemory()) &&
(numAliased >= AliasedCheckLimit ||
SLP->isAliased(SrcLoc, SrcInst, DepDest->Inst)))) {
// We increment the counter only if the locations are aliased
// (instead of counting all alias checks). This gives a better
// balance between reduced runtime and accurate dependencies.
numAliased++;
DepDest->MemoryDependencies.push_back(BundleMember);
BundleMember->Dependencies++;
ScheduleData *DestBundle = DepDest->FirstInBundle;
if (!DestBundle->IsScheduled) {
BundleMember->incrementUnscheduledDeps(1);
}
if (!DestBundle->hasValidDependencies()) {
WorkList.push_back(DestBundle);
}
}
DepDest = DepDest->NextLoadStore;
// Example, explaining the loop break condition: Let's assume our
// starting instruction is i0 and MaxMemDepDistance = 3.
//
// +--------v--v--v
// i0,i1,i2,i3,i4,i5,i6,i7,i8
// +--------^--^--^
//
// MaxMemDepDistance let us stop alias-checking at i3 and we add
// dependencies from i0 to i3,i4,.. (even if they are not aliased).
// Previously we already added dependencies from i3 to i6,i7,i8
// (because of MaxMemDepDistance). As we added a dependency from
// i0 to i3, we have transitive dependencies from i0 to i6,i7,i8
// and we can abort this loop at i6.
if (DistToSrc >= 2 * MaxMemDepDistance)
break;
DistToSrc++;
}
}
}
BundleMember = BundleMember->NextInBundle;
}
if (InsertInReadyList && SD->isReady()) {
ReadyInsts.push_back(SD);
DEBUG(dbgs() << "SLP: gets ready on update: " << *SD->Inst << "\n");
}
}
}
void BoUpSLP::BlockScheduling::resetSchedule() {
assert(ScheduleStart &&
"tried to reset schedule on block which has not been scheduled");
for (Instruction *I = ScheduleStart; I != ScheduleEnd; I = I->getNextNode()) {
ScheduleData *SD = getScheduleData(I);
assert(isInSchedulingRegion(SD));
SD->IsScheduled = false;
SD->resetUnscheduledDeps();
}
ReadyInsts.clear();
}
void BoUpSLP::scheduleBlock(BlockScheduling *BS) {
if (!BS->ScheduleStart)
return;
DEBUG(dbgs() << "SLP: schedule block " << BS->BB->getName() << "\n");
BS->resetSchedule();
// For the real scheduling we use a more sophisticated ready-list: it is
// sorted by the original instruction location. This lets the final schedule
// be as close as possible to the original instruction order.
struct ScheduleDataCompare {
bool operator()(ScheduleData *SD1, ScheduleData *SD2) {
return SD2->SchedulingPriority < SD1->SchedulingPriority;
}
};
std::set<ScheduleData *, ScheduleDataCompare> ReadyInsts;
// Ensure that all depencency data is updated and fill the ready-list with
// initial instructions.
int Idx = 0;
int NumToSchedule = 0;
for (auto *I = BS->ScheduleStart; I != BS->ScheduleEnd;
I = I->getNextNode()) {
ScheduleData *SD = BS->getScheduleData(I);
assert(
SD->isPartOfBundle() == (ScalarToTreeEntry.count(SD->Inst) != 0) &&
"scheduler and vectorizer have different opinion on what is a bundle");
SD->FirstInBundle->SchedulingPriority = Idx++;
if (SD->isSchedulingEntity()) {
BS->calculateDependencies(SD, false, this);
NumToSchedule++;
}
}
BS->initialFillReadyList(ReadyInsts);
Instruction *LastScheduledInst = BS->ScheduleEnd;
// Do the "real" scheduling.
while (!ReadyInsts.empty()) {
ScheduleData *picked = *ReadyInsts.begin();
ReadyInsts.erase(ReadyInsts.begin());
// Move the scheduled instruction(s) to their dedicated places, if not
// there yet.
ScheduleData *BundleMember = picked;
while (BundleMember) {
Instruction *pickedInst = BundleMember->Inst;
if (LastScheduledInst->getNextNode() != pickedInst) {
BS->BB->getInstList().remove(pickedInst);
BS->BB->getInstList().insert(LastScheduledInst, pickedInst);
}
LastScheduledInst = pickedInst;
BundleMember = BundleMember->NextInBundle;
}
BS->schedule(picked, ReadyInsts);
NumToSchedule--;
}
assert(NumToSchedule == 0 && "could not schedule all instructions");
// Avoid duplicate scheduling of the block.
BS->ScheduleStart = nullptr;
}
/// The SLPVectorizer Pass.
struct SLPVectorizer : public FunctionPass {
typedef SmallVector<StoreInst *, 8> StoreList;
typedef MapVector<Value *, StoreList> StoreListMap;
/// Pass identification, replacement for typeid
static char ID;
explicit SLPVectorizer() : FunctionPass(ID) {
initializeSLPVectorizerPass(*PassRegistry::getPassRegistry());
}
ScalarEvolution *SE;
TargetTransformInfo *TTI;
TargetLibraryInfo *TLI;
AliasAnalysis *AA;
LoopInfo *LI;
DominatorTree *DT;
AssumptionCache *AC;
bool runOnFunction(Function &F) override {
if (skipOptnoneFunction(F))
return false;
SE = &getAnalysis<ScalarEvolution>();
TTI = &getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
auto *TLIP = getAnalysisIfAvailable<TargetLibraryInfoWrapperPass>();
TLI = TLIP ? &TLIP->getTLI() : nullptr;
AA = &getAnalysis<AliasAnalysis>();
LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
AC = &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
StoreRefs.clear();
bool Changed = false;
// If the target claims to have no vector registers don't attempt
// vectorization.
if (!TTI->getNumberOfRegisters(true))
return false;
// Use the vector register size specified by the target unless overridden
// by a command-line option.
// TODO: It would be better to limit the vectorization factor based on
// data type rather than just register size. For example, x86 AVX has
// 256-bit registers, but it does not support integer operations
// at that width (that requires AVX2).
if (MaxVectorRegSizeOption.getNumOccurrences())
MaxVecRegSize = MaxVectorRegSizeOption;
else
MaxVecRegSize = TTI->getRegisterBitWidth(true);
// Don't vectorize when the attribute NoImplicitFloat is used.
if (F.hasFnAttribute(Attribute::NoImplicitFloat))
return false;
DEBUG(dbgs() << "SLP: Analyzing blocks in " << F.getName() << ".\n");
// Use the bottom up slp vectorizer to construct chains that start with
// store instructions.
BoUpSLP R(&F, SE, TTI, TLI, AA, LI, DT, AC);
// A general note: the vectorizer must use BoUpSLP::eraseInstruction() to
// delete instructions.
// Scan the blocks in the function in post order.
for (auto BB : post_order(&F.getEntryBlock())) {
// Vectorize trees that end at stores.
if (unsigned count = collectStores(BB, R)) {
(void)count;
DEBUG(dbgs() << "SLP: Found " << count << " stores to vectorize.\n");
Changed |= vectorizeStoreChains(R);
}
// Vectorize trees that end at reductions.
Changed |= vectorizeChainsInBlock(BB, R);
}
if (Changed) {
R.optimizeGatherSequence();
DEBUG(dbgs() << "SLP: vectorized \"" << F.getName() << "\"\n");
DEBUG(verifyFunction(F));
}
return Changed;
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
FunctionPass::getAnalysisUsage(AU);
AU.addRequired<AssumptionCacheTracker>();
AU.addRequired<ScalarEvolution>();
AU.addRequired<AliasAnalysis>();
AU.addRequired<TargetTransformInfoWrapperPass>();
AU.addRequired<LoopInfoWrapperPass>();
AU.addRequired<DominatorTreeWrapperPass>();
AU.addPreserved<LoopInfoWrapperPass>();
AU.addPreserved<DominatorTreeWrapperPass>();
AU.setPreservesCFG();
}
private:
/// \brief Collect memory references and sort them according to their base
/// object. We sort the stores to their base objects to reduce the cost of the
/// quadratic search on the stores. TODO: We can further reduce this cost
/// if we flush the chain creation every time we run into a memory barrier.
unsigned collectStores(BasicBlock *BB, BoUpSLP &R);
/// \brief Try to vectorize a chain that starts at two arithmetic instrs.
bool tryToVectorizePair(Value *A, Value *B, BoUpSLP &R);
/// \brief Try to vectorize a list of operands.
/// \@param BuildVector A list of users to ignore for the purpose of
/// scheduling and that don't need extracting.
/// \returns true if a value was vectorized.
bool tryToVectorizeList(ArrayRef<Value *> VL, BoUpSLP &R,
ArrayRef<Value *> BuildVector = None,
bool allowReorder = false);
/// \brief Try to vectorize a chain that may start at the operands of \V;
bool tryToVectorize(BinaryOperator *V, BoUpSLP &R);
/// \brief Vectorize the stores that were collected in StoreRefs.
bool vectorizeStoreChains(BoUpSLP &R);
/// \brief Scan the basic block and look for patterns that are likely to start
/// a vectorization chain.
bool vectorizeChainsInBlock(BasicBlock *BB, BoUpSLP &R);
bool vectorizeStoreChain(ArrayRef<Value *> Chain, int CostThreshold,
BoUpSLP &R, unsigned VecRegSize);
bool vectorizeStores(ArrayRef<StoreInst *> Stores, int costThreshold,
BoUpSLP &R);
private:
StoreListMap StoreRefs;
unsigned MaxVecRegSize; // This is set by TTI or overridden by cl::opt.
};
/// \brief Check that the Values in the slice in VL array are still existent in
/// the WeakTrackingVH array.
/// Vectorization of part of the VL array may cause later values in the VL array
/// to become invalid. We track when this has happened in the WeakTrackingVH
/// array.
static bool hasValueBeenRAUWed(ArrayRef<Value *> VL,
ArrayRef<WeakTrackingVH> VH, unsigned SliceBegin,
unsigned SliceSize) {
VL = VL.slice(SliceBegin, SliceSize);
VH = VH.slice(SliceBegin, SliceSize);
return !std::equal(VL.begin(), VL.end(), VH.begin());
}
bool SLPVectorizer::vectorizeStoreChain(ArrayRef<Value *> Chain,
int CostThreshold, BoUpSLP &R,
unsigned VecRegSize) {
unsigned ChainLen = Chain.size();
DEBUG(dbgs() << "SLP: Analyzing a store chain of length " << ChainLen
<< "\n");
Type *StoreTy = cast<StoreInst>(Chain[0])->getValueOperand()->getType();
auto &DL = cast<StoreInst>(Chain[0])->getModule()->getDataLayout();
unsigned Sz = DL.getTypeSizeInBits(StoreTy);
unsigned VF = VecRegSize / Sz;
if (!isPowerOf2_32(Sz) || VF < 2)
return false;
// Keep track of values that were deleted by vectorizing in the loop below.
SmallVector<WeakTrackingVH, 8> TrackValues(Chain.begin(), Chain.end());
bool Changed = false;
// Look for profitable vectorizable trees at all offsets, starting at zero.
for (unsigned i = 0, e = ChainLen; i < e; ++i) {
if (i + VF > e)
break;
// Check that a previous iteration of this loop did not delete the Value.
if (hasValueBeenRAUWed(Chain, TrackValues, i, VF))
continue;
DEBUG(dbgs() << "SLP: Analyzing " << VF << " stores at offset " << i
<< "\n");
ArrayRef<Value *> Operands = Chain.slice(i, VF);
R.buildTree(Operands);
int Cost = R.getTreeCost();
DEBUG(dbgs() << "SLP: Found cost=" << Cost << " for VF=" << VF << "\n");
if (Cost < CostThreshold) {
DEBUG(dbgs() << "SLP: Decided to vectorize cost=" << Cost << "\n");
R.vectorizeTree();
// Move to the next bundle.
i += VF - 1;
Changed = true;
}
}
return Changed;
}
bool SLPVectorizer::vectorizeStores(ArrayRef<StoreInst *> Stores,
int costThreshold, BoUpSLP &R) {
SetVector<StoreInst *> Heads, Tails;
SmallDenseMap<StoreInst *, StoreInst *> ConsecutiveChain;
// We may run into multiple chains that merge into a single chain. We mark the
// stores that we vectorized so that we don't visit the same store twice.
BoUpSLP::ValueSet VectorizedStores;
bool Changed = false;
// Do a quadratic search on all of the given stores and find
// all of the pairs of stores that follow each other.
for (unsigned i = 0, e = Stores.size(); i < e; ++i) {
for (unsigned j = 0; j < e; ++j) {
if (i == j)
continue;
const DataLayout &DL = Stores[i]->getModule()->getDataLayout();
if (R.isConsecutiveAccess(Stores[i], Stores[j], DL)) {
Tails.insert(Stores[j]);
Heads.insert(Stores[i]);
ConsecutiveChain[Stores[i]] = Stores[j];
}
}
}
// For stores that start but don't end a link in the chain:
for (SetVector<StoreInst *>::iterator it = Heads.begin(), e = Heads.end();
it != e; ++it) {
if (Tails.count(*it))
continue;
// We found a store instr that starts a chain. Now follow the chain and try
// to vectorize it.
BoUpSLP::ValueList Operands;
StoreInst *I = *it;
// Collect the chain into a list.
while (Tails.count(I) || Heads.count(I)) {
if (VectorizedStores.count(I))
break;
Operands.push_back(I);
// Move to the next value in the chain.
I = ConsecutiveChain[I];
}
// FIXME: Is division-by-2 the correct step? Should we assert that the
// register size is a power-of-2?
for (unsigned Size = MaxVecRegSize; Size >= MinVecRegSize; Size /= 2) {
if (vectorizeStoreChain(Operands, costThreshold, R, Size)) {
// Mark the vectorized stores so that we don't vectorize them again.
VectorizedStores.insert(Operands.begin(), Operands.end());
Changed = true;
break;
}
}
}
return Changed;
}
unsigned SLPVectorizer::collectStores(BasicBlock *BB, BoUpSLP &R) {
unsigned count = 0;
StoreRefs.clear();
const DataLayout &DL = BB->getModule()->getDataLayout();
for (Instruction &I : *BB) {
StoreInst *SI = dyn_cast<StoreInst>(&I);
if (!SI)
continue;
// Don't touch volatile stores.
if (!SI->isSimple())
continue;
// Check that the pointer points to scalars.
Type *Ty = SI->getValueOperand()->getType();
if (!isValidElementType(Ty))
continue;
// Find the base pointer.
Value *Ptr = GetUnderlyingObject(SI->getPointerOperand(), DL);
// Save the store locations.
StoreRefs[Ptr].push_back(SI);
count++;
}
return count;
}
bool SLPVectorizer::tryToVectorizePair(Value *A, Value *B, BoUpSLP &R) {
if (!A || !B)
return false;
Value *VL[] = { A, B };
return tryToVectorizeList(VL, R, None, true);
}
bool SLPVectorizer::tryToVectorizeList(ArrayRef<Value *> VL, BoUpSLP &R,
ArrayRef<Value *> BuildVector,
bool allowReorder) {
if (VL.size() < 2)
return false;
DEBUG(dbgs() << "SLP: Vectorizing a list of length = " << VL.size() << ".\n");
// Check that all of the parts are scalar instructions of the same type.
Instruction *I0 = dyn_cast<Instruction>(VL[0]);
if (!I0)
return false;
unsigned Opcode0 = I0->getOpcode();
const DataLayout &DL = I0->getModule()->getDataLayout();
Type *Ty0 = I0->getType();
unsigned Sz = DL.getTypeSizeInBits(Ty0);
// FIXME: Register size should be a parameter to this function, so we can
// try different vectorization factors.
unsigned VF = MinVecRegSize / Sz;
for (Value *V : VL) {
Type *Ty = V->getType();
if (!isValidElementType(Ty))
return false;
Instruction *Inst = dyn_cast<Instruction>(V);
if (!Inst || Inst->getOpcode() != Opcode0)
return false;
}
bool Changed = false;
// Keep track of values that were deleted by vectorizing in the loop below.
SmallVector<WeakTrackingVH, 8> TrackValues(VL.begin(), VL.end());
for (unsigned i = 0, e = VL.size(); i < e; ++i) {
unsigned OpsWidth = 0;
if (i + VF > e)
OpsWidth = e - i;
else
OpsWidth = VF;
if (!isPowerOf2_32(OpsWidth) || OpsWidth < 2)
break;
// Check that a previous iteration of this loop did not delete the Value.
if (hasValueBeenRAUWed(VL, TrackValues, i, OpsWidth))
continue;
DEBUG(dbgs() << "SLP: Analyzing " << OpsWidth << " operations "
<< "\n");
ArrayRef<Value *> Ops = VL.slice(i, OpsWidth);
ArrayRef<Value *> BuildVectorSlice;
if (!BuildVector.empty())
BuildVectorSlice = BuildVector.slice(i, OpsWidth);
R.buildTree(Ops, BuildVectorSlice);
// TODO: check if we can allow reordering also for other cases than
// tryToVectorizePair()
if (allowReorder && R.shouldReorder()) {
assert(Ops.size() == 2);
assert(BuildVectorSlice.empty());
Value *ReorderedOps[] = { Ops[1], Ops[0] };
R.buildTree(ReorderedOps, None);
}
int Cost = R.getTreeCost();
if (Cost < -SLPCostThreshold) {
DEBUG(dbgs() << "SLP: Vectorizing list at cost:" << Cost << ".\n");
Value *VectorizedRoot = R.vectorizeTree();
// Reconstruct the build vector by extracting the vectorized root. This
// way we handle the case where some elements of the vector are undefined.
// (return (inserelt <4 xi32> (insertelt undef (opd0) 0) (opd1) 2))
if (!BuildVectorSlice.empty()) {
// The insert point is the last build vector instruction. The vectorized
// root will precede it. This guarantees that we get an instruction. The
// vectorized tree could have been constant folded.
Instruction *InsertAfter = cast<Instruction>(BuildVectorSlice.back());
unsigned VecIdx = 0;
for (auto &V : BuildVectorSlice) {
IRBuilder<true, NoFolder> Builder(
++BasicBlock::iterator(InsertAfter));
InsertElementInst *IE = cast<InsertElementInst>(V);
Instruction *Extract = cast<Instruction>(Builder.CreateExtractElement(
VectorizedRoot, Builder.getInt32(VecIdx++)));
IE->setOperand(1, Extract);
IE->removeFromParent();
IE->insertAfter(Extract);
InsertAfter = IE;
}
}
// Move to the next bundle.
i += VF - 1;
Changed = true;
}
}
return Changed;
}
bool SLPVectorizer::tryToVectorize(BinaryOperator *V, BoUpSLP &R) {
if (!V)
return false;
// Try to vectorize V.
if (tryToVectorizePair(V->getOperand(0), V->getOperand(1), R))
return true;
BinaryOperator *A = dyn_cast<BinaryOperator>(V->getOperand(0));
BinaryOperator *B = dyn_cast<BinaryOperator>(V->getOperand(1));
// Try to skip B.
if (B && B->hasOneUse()) {
BinaryOperator *B0 = dyn_cast<BinaryOperator>(B->getOperand(0));
BinaryOperator *B1 = dyn_cast<BinaryOperator>(B->getOperand(1));
if (tryToVectorizePair(A, B0, R)) {
return true;
}
if (tryToVectorizePair(A, B1, R)) {
return true;
}
}
// Try to skip A.
if (A && A->hasOneUse()) {
BinaryOperator *A0 = dyn_cast<BinaryOperator>(A->getOperand(0));
BinaryOperator *A1 = dyn_cast<BinaryOperator>(A->getOperand(1));
if (tryToVectorizePair(A0, B, R)) {
return true;
}
if (tryToVectorizePair(A1, B, R)) {
return true;
}
}
return 0;
}
/// \brief Generate a shuffle mask to be used in a reduction tree.
///
/// \param VecLen The length of the vector to be reduced.
/// \param NumEltsToRdx The number of elements that should be reduced in the
/// vector.
/// \param IsPairwise Whether the reduction is a pairwise or splitting
/// reduction. A pairwise reduction will generate a mask of
/// <0,2,...> or <1,3,..> while a splitting reduction will generate
/// <2,3, undef,undef> for a vector of 4 and NumElts = 2.
/// \param IsLeft True will generate a mask of even elements, odd otherwise.
static Value *createRdxShuffleMask(unsigned VecLen, unsigned NumEltsToRdx,
bool IsPairwise, bool IsLeft,
IRBuilder<> &Builder) {
assert((IsPairwise || !IsLeft) && "Don't support a <0,1,undef,...> mask");
SmallVector<Constant *, 32> ShuffleMask(
VecLen, UndefValue::get(Builder.getInt32Ty()));
if (IsPairwise)
// Build a mask of 0, 2, ... (left) or 1, 3, ... (right).
for (unsigned i = 0; i != NumEltsToRdx; ++i)
ShuffleMask[i] = Builder.getInt32(2 * i + !IsLeft);
else
// Move the upper half of the vector to the lower half.
for (unsigned i = 0; i != NumEltsToRdx; ++i)
ShuffleMask[i] = Builder.getInt32(NumEltsToRdx + i);
return ConstantVector::get(ShuffleMask);
}
/// Model horizontal reductions.
///
/// A horizontal reduction is a tree of reduction operations (currently add and
/// fadd) that has operations that can be put into a vector as its leaf.
/// For example, this tree:
///
/// mul mul mul mul
/// \ / \ /
/// + +
/// \ /
/// +
/// This tree has "mul" as its reduced values and "+" as its reduction
/// operations. A reduction might be feeding into a store or a binary operation
/// feeding a phi.
/// ...
/// \ /
/// +
/// |
/// phi +=
///
/// Or:
/// ...
/// \ /
/// +
/// |
/// *p =
///
class HorizontalReduction {
SmallVector<Value *, 16> ReductionOps;
SmallVector<Value *, 32> ReducedVals;
BinaryOperator *ReductionRoot;
PHINode *ReductionPHI;
/// The opcode of the reduction.
unsigned ReductionOpcode;
/// The opcode of the values we perform a reduction on.
unsigned ReducedValueOpcode;
/// The width of one full horizontal reduction operation.
unsigned ReduxWidth;
/// Should we model this reduction as a pairwise reduction tree or a tree that
/// splits the vector in halves and adds those halves.
bool IsPairwiseReduction;
public:
HorizontalReduction()
: ReductionRoot(nullptr), ReductionPHI(nullptr), ReductionOpcode(0),
ReducedValueOpcode(0), ReduxWidth(0), IsPairwiseReduction(false) {}
/// \brief Try to find a reduction tree.
bool matchAssociativeReduction(PHINode *Phi, BinaryOperator *B) {
assert((!Phi ||
std::find(Phi->op_begin(), Phi->op_end(), B) != Phi->op_end()) &&
"Thi phi needs to use the binary operator");
// We could have a initial reductions that is not an add.
// r *= v1 + v2 + v3 + v4
// In such a case start looking for a tree rooted in the first '+'.
if (Phi) {
if (B->getOperand(0) == Phi) {
Phi = nullptr;
B = dyn_cast<BinaryOperator>(B->getOperand(1));
} else if (B->getOperand(1) == Phi) {
Phi = nullptr;
B = dyn_cast<BinaryOperator>(B->getOperand(0));
}
}
if (!B)
return false;
Type *Ty = B->getType();
if (!isValidElementType(Ty))
return false;
const DataLayout &DL = B->getModule()->getDataLayout();
ReductionOpcode = B->getOpcode();
ReducedValueOpcode = 0;
// FIXME: Register size should be a parameter to this function, so we can
// try different vectorization factors.
ReduxWidth = MinVecRegSize / DL.getTypeSizeInBits(Ty);
ReductionRoot = B;
ReductionPHI = Phi;
if (ReduxWidth < 4)
return false;
// We currently only support adds.
if (ReductionOpcode != Instruction::Add &&
ReductionOpcode != Instruction::FAdd)
return false;
// Post order traverse the reduction tree starting at B. We only handle true
// trees containing only binary operators.
SmallVector<std::pair<BinaryOperator *, unsigned>, 32> Stack;
Stack.push_back(std::make_pair(B, 0));
while (!Stack.empty()) {
BinaryOperator *TreeN = Stack.back().first;
unsigned EdgeToVist = Stack.back().second++;
bool IsReducedValue = TreeN->getOpcode() != ReductionOpcode;
// Only handle trees in the current basic block.
if (TreeN->getParent() != B->getParent())
return false;
// Each tree node needs to have one user except for the ultimate
// reduction.
if (!TreeN->hasOneUse() && TreeN != B)
return false;
// Postorder vist.
if (EdgeToVist == 2 || IsReducedValue) {
if (IsReducedValue) {
// Make sure that the opcodes of the operations that we are going to
// reduce match.
if (!ReducedValueOpcode)
ReducedValueOpcode = TreeN->getOpcode();
else if (ReducedValueOpcode != TreeN->getOpcode())
return false;
ReducedVals.push_back(TreeN);
} else {
// We need to be able to reassociate the adds.
if (!TreeN->isAssociative())
return false;
ReductionOps.push_back(TreeN);
}
// Retract.
Stack.pop_back();
continue;
}
// Visit left or right.
Value *NextV = TreeN->getOperand(EdgeToVist);
BinaryOperator *Next = dyn_cast<BinaryOperator>(NextV);
if (Next)
Stack.push_back(std::make_pair(Next, 0));
else if (NextV != Phi)
return false;
}
return true;
}
/// \brief Attempt to vectorize the tree found by
/// matchAssociativeReduction.
bool tryToReduce(BoUpSLP &V, TargetTransformInfo *TTI) {
if (ReducedVals.empty())
return false;
unsigned NumReducedVals = ReducedVals.size();
if (NumReducedVals < ReduxWidth)
return false;
Value *VectorizedTree = nullptr;
IRBuilder<> Builder(ReductionRoot);
FastMathFlags Unsafe;
Unsafe.setUnsafeAlgebra();
Builder.SetFastMathFlags(Unsafe);
unsigned i = 0;
for (; i < NumReducedVals - ReduxWidth + 1; i += ReduxWidth) {
V.buildTree(makeArrayRef(&ReducedVals[i], ReduxWidth), ReductionOps);
// Estimate cost.
int Cost = V.getTreeCost() + getReductionCost(TTI, ReducedVals[i]);
if (Cost >= -SLPCostThreshold)
break;
DEBUG(dbgs() << "SLP: Vectorizing horizontal reduction at cost:" << Cost
<< ". (HorRdx)\n");
// Vectorize a tree.
DebugLoc Loc = cast<Instruction>(ReducedVals[i])->getDebugLoc();
Value *VectorizedRoot = V.vectorizeTree();
// Emit a reduction.
Value *ReducedSubTree = emitReduction(VectorizedRoot, Builder);
if (VectorizedTree) {
Builder.SetCurrentDebugLocation(Loc);
VectorizedTree = createBinOp(Builder, ReductionOpcode, VectorizedTree,
ReducedSubTree, "bin.rdx");
} else
VectorizedTree = ReducedSubTree;
}
if (VectorizedTree) {
// Finish the reduction.
for (; i < NumReducedVals; ++i) {
Builder.SetCurrentDebugLocation(
cast<Instruction>(ReducedVals[i])->getDebugLoc());
VectorizedTree = createBinOp(Builder, ReductionOpcode, VectorizedTree,
ReducedVals[i]);
}
// Update users.
if (ReductionPHI) {
assert(ReductionRoot && "Need a reduction operation");
ReductionRoot->setOperand(0, VectorizedTree);
ReductionRoot->setOperand(1, ReductionPHI);
} else
ReductionRoot->replaceAllUsesWith(VectorizedTree);
}
return VectorizedTree != nullptr;
}
private:
/// \brief Calcuate the cost of a reduction.
int getReductionCost(TargetTransformInfo *TTI, Value *FirstReducedVal) {
Type *ScalarTy = FirstReducedVal->getType();
Type *VecTy = VectorType::get(ScalarTy, ReduxWidth);
int PairwiseRdxCost = TTI->getReductionCost(ReductionOpcode, VecTy, true);
int SplittingRdxCost = TTI->getReductionCost(ReductionOpcode, VecTy, false);
IsPairwiseReduction = PairwiseRdxCost < SplittingRdxCost;
int VecReduxCost = IsPairwiseReduction ? PairwiseRdxCost : SplittingRdxCost;
int ScalarReduxCost =
ReduxWidth * TTI->getArithmeticInstrCost(ReductionOpcode, VecTy);
DEBUG(dbgs() << "SLP: Adding cost " << VecReduxCost - ScalarReduxCost
<< " for reduction that starts with " << *FirstReducedVal
<< " (It is a "
<< (IsPairwiseReduction ? "pairwise" : "splitting")
<< " reduction)\n");
return VecReduxCost - ScalarReduxCost;
}
static Value *createBinOp(IRBuilder<> &Builder, unsigned Opcode, Value *L,
Value *R, const Twine &Name = "") {
if (Opcode == Instruction::FAdd)
return Builder.CreateFAdd(L, R, Name);
return Builder.CreateBinOp((Instruction::BinaryOps)Opcode, L, R, Name);
}
/// \brief Emit a horizontal reduction of the vectorized value.
Value *emitReduction(Value *VectorizedValue, IRBuilder<> &Builder) {
assert(VectorizedValue && "Need to have a vectorized tree node");
assert(isPowerOf2_32(ReduxWidth) &&
"We only handle power-of-two reductions for now");
Value *TmpVec = VectorizedValue;
for (unsigned i = ReduxWidth / 2; i != 0; i >>= 1) {
if (IsPairwiseReduction) {
Value *LeftMask =
createRdxShuffleMask(ReduxWidth, i, true, true, Builder);
Value *RightMask =
createRdxShuffleMask(ReduxWidth, i, true, false, Builder);
Value *LeftShuf = Builder.CreateShuffleVector(
TmpVec, UndefValue::get(TmpVec->getType()), LeftMask, "rdx.shuf.l");
Value *RightShuf = Builder.CreateShuffleVector(
TmpVec, UndefValue::get(TmpVec->getType()), (RightMask),
"rdx.shuf.r");
TmpVec = createBinOp(Builder, ReductionOpcode, LeftShuf, RightShuf,
"bin.rdx");
} else {
Value *UpperHalf =
createRdxShuffleMask(ReduxWidth, i, false, false, Builder);
Value *Shuf = Builder.CreateShuffleVector(
TmpVec, UndefValue::get(TmpVec->getType()), UpperHalf, "rdx.shuf");
TmpVec = createBinOp(Builder, ReductionOpcode, TmpVec, Shuf, "bin.rdx");
}
}
// The result is in the first element of the vector.
return Builder.CreateExtractElement(TmpVec, Builder.getInt32(0));
}
};
/// \brief Recognize construction of vectors like
/// %ra = insertelement <4 x float> undef, float %s0, i32 0
/// %rb = insertelement <4 x float> %ra, float %s1, i32 1
/// %rc = insertelement <4 x float> %rb, float %s2, i32 2
/// %rd = insertelement <4 x float> %rc, float %s3, i32 3
///
/// Returns true if it matches
///
static bool findBuildVector(InsertElementInst *FirstInsertElem,
SmallVectorImpl<Value *> &BuildVector,
SmallVectorImpl<Value *> &BuildVectorOpds) {
if (!isa<UndefValue>(FirstInsertElem->getOperand(0)))
return false;
InsertElementInst *IE = FirstInsertElem;
while (true) {
BuildVector.push_back(IE);
BuildVectorOpds.push_back(IE->getOperand(1));
if (IE->use_empty())
return false;
InsertElementInst *NextUse = dyn_cast<InsertElementInst>(IE->user_back());
if (!NextUse)
return true;
// If this isn't the final use, make sure the next insertelement is the only
// use. It's OK if the final constructed vector is used multiple times
if (!IE->hasOneUse())
return false;
IE = NextUse;
}
return false;
}
static bool PhiTypeSorterFunc(Value *V, Value *V2) {
return V->getType() < V2->getType();
}
bool SLPVectorizer::vectorizeChainsInBlock(BasicBlock *BB, BoUpSLP &R) {
bool Changed = false;
SmallVector<Value *, 4> Incoming;
SmallSet<Value *, 16> VisitedInstrs;
bool HaveVectorizedPhiNodes = true;
while (HaveVectorizedPhiNodes) {
HaveVectorizedPhiNodes = false;
// Collect the incoming values from the PHIs.
Incoming.clear();
for (BasicBlock::iterator instr = BB->begin(), ie = BB->end(); instr != ie;
++instr) {
PHINode *P = dyn_cast<PHINode>(instr);
if (!P)
break;
if (!VisitedInstrs.count(P))
Incoming.push_back(P);
}
// Sort by type.
std::stable_sort(Incoming.begin(), Incoming.end(), PhiTypeSorterFunc);
// Try to vectorize elements base on their type.
for (SmallVector<Value *, 4>::iterator IncIt = Incoming.begin(),
E = Incoming.end();
IncIt != E;) {
// Look for the next elements with the same type.
SmallVector<Value *, 4>::iterator SameTypeIt = IncIt;
while (SameTypeIt != E &&
(*SameTypeIt)->getType() == (*IncIt)->getType()) {
VisitedInstrs.insert(*SameTypeIt);
++SameTypeIt;
}
// Try to vectorize them.
unsigned NumElts = (SameTypeIt - IncIt);
DEBUG(errs() << "SLP: Trying to vectorize starting at PHIs (" << NumElts << ")\n");
if (NumElts > 1 && tryToVectorizeList(makeArrayRef(IncIt, NumElts), R)) {
// Success start over because instructions might have been changed.
HaveVectorizedPhiNodes = true;
Changed = true;
break;
}
// Start over at the next instruction of a different type (or the end).
IncIt = SameTypeIt;
}
}
VisitedInstrs.clear();
for (BasicBlock::iterator it = BB->begin(), e = BB->end(); it != e; it++) {
// We may go through BB multiple times so skip the one we have checked.
if (!VisitedInstrs.insert(it).second)
continue;
if (isa<DbgInfoIntrinsic>(it))
continue;
// Try to vectorize reductions that use PHINodes.
if (PHINode *P = dyn_cast<PHINode>(it)) {
// Check that the PHI is a reduction PHI.
if (P->getNumIncomingValues() != 2)
return Changed;
Value *Rdx =
(P->getIncomingBlock(0) == BB
? (P->getIncomingValue(0))
: (P->getIncomingBlock(1) == BB ? P->getIncomingValue(1)
: nullptr));
// Check if this is a Binary Operator.
BinaryOperator *BI = dyn_cast_or_null<BinaryOperator>(Rdx);
if (!BI)
continue;
// Try to match and vectorize a horizontal reduction.
HorizontalReduction HorRdx;
if (ShouldVectorizeHor && HorRdx.matchAssociativeReduction(P, BI) &&
HorRdx.tryToReduce(R, TTI)) {
Changed = true;
it = BB->begin();
e = BB->end();
continue;
}
Value *Inst = BI->getOperand(0);
if (Inst == P)
Inst = BI->getOperand(1);
if (tryToVectorize(dyn_cast<BinaryOperator>(Inst), R)) {
// We would like to start over since some instructions are deleted
// and the iterator may become invalid value.
Changed = true;
it = BB->begin();
e = BB->end();
continue;
}
continue;
}
// Try to vectorize horizontal reductions feeding into a store.
if (ShouldStartVectorizeHorAtStore)
if (StoreInst *SI = dyn_cast<StoreInst>(it))
if (BinaryOperator *BinOp =
dyn_cast<BinaryOperator>(SI->getValueOperand())) {
HorizontalReduction HorRdx;
if (((HorRdx.matchAssociativeReduction(nullptr, BinOp) &&
HorRdx.tryToReduce(R, TTI)) ||
tryToVectorize(BinOp, R))) {
Changed = true;
it = BB->begin();
e = BB->end();
continue;
}
}
// Try to vectorize horizontal reductions feeding into a return.
if (ReturnInst *RI = dyn_cast<ReturnInst>(it))
if (RI->getNumOperands() != 0)
if (BinaryOperator *BinOp =
dyn_cast<BinaryOperator>(RI->getOperand(0))) {
DEBUG(dbgs() << "SLP: Found a return to vectorize.\n");
if (tryToVectorizePair(BinOp->getOperand(0),
BinOp->getOperand(1), R)) {
Changed = true;
it = BB->begin();
e = BB->end();
continue;
}
}
// Try to vectorize trees that start at compare instructions.
if (CmpInst *CI = dyn_cast<CmpInst>(it)) {
if (tryToVectorizePair(CI->getOperand(0), CI->getOperand(1), R)) {
Changed = true;
// We would like to start over since some instructions are deleted
// and the iterator may become invalid value.
it = BB->begin();
e = BB->end();
continue;
}
for (int i = 0; i < 2; ++i) {
if (BinaryOperator *BI = dyn_cast<BinaryOperator>(CI->getOperand(i))) {
if (tryToVectorizePair(BI->getOperand(0), BI->getOperand(1), R)) {
Changed = true;
// We would like to start over since some instructions are deleted
// and the iterator may become invalid value.
it = BB->begin();
e = BB->end();
break;
}
}
}
continue;
}
// Try to vectorize trees that start at insertelement instructions.
if (InsertElementInst *FirstInsertElem = dyn_cast<InsertElementInst>(it)) {
SmallVector<Value *, 16> BuildVector;
SmallVector<Value *, 16> BuildVectorOpds;
if (!findBuildVector(FirstInsertElem, BuildVector, BuildVectorOpds))
continue;
// Vectorize starting with the build vector operands ignoring the
// BuildVector instructions for the purpose of scheduling and user
// extraction.
if (tryToVectorizeList(BuildVectorOpds, R, BuildVector)) {
Changed = true;
it = BB->begin();
e = BB->end();
}
continue;
}
}
return Changed;
}
bool SLPVectorizer::vectorizeStoreChains(BoUpSLP &R) {
bool Changed = false;
// Attempt to sort and vectorize each of the store-groups.
for (StoreListMap::iterator it = StoreRefs.begin(), e = StoreRefs.end();
it != e; ++it) {
if (it->second.size() < 2)
continue;
DEBUG(dbgs() << "SLP: Analyzing a store chain of length "
<< it->second.size() << ".\n");
// Process the stores in chunks of 16.
// TODO: The limit of 16 inhibits greater vectorization factors.
// For example, AVX2 supports v32i8. Increasing this limit, however,
// may cause a significant compile-time increase.
for (unsigned CI = 0, CE = it->second.size(); CI < CE; CI+=16) {
unsigned Len = std::min<unsigned>(CE - CI, 16);
Changed |= vectorizeStores(makeArrayRef(&it->second[CI], Len),
-SLPCostThreshold, R);
}
}
return Changed;
}
} // end anonymous namespace
char SLPVectorizer::ID = 0;
static const char lv_name[] = "SLP Vectorizer";
INITIALIZE_PASS_BEGIN(SLPVectorizer, SV_NAME, lv_name, false, false)
INITIALIZE_AG_DEPENDENCY(AliasAnalysis)
INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)
INITIALIZE_PASS_DEPENDENCY(ScalarEvolution)
INITIALIZE_PASS_DEPENDENCY(LoopSimplify)
INITIALIZE_PASS_END(SLPVectorizer, SV_NAME, lv_name, false, false)
namespace llvm {
Pass *createSLPVectorizerPass() { return new SLPVectorizer(); }
}
|
0 | repos/DirectXShaderCompiler/lib/Transforms | repos/DirectXShaderCompiler/lib/Transforms/Vectorize/Vectorize.cpp | //===-- Vectorize.cpp -----------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements common infrastructure for libLLVMVectorizeOpts.a, which
// implements several vectorization transformations over the LLVM intermediate
// representation, including the C bindings for that library.
//
//===----------------------------------------------------------------------===//
#if HLSL_VECTORIZATION_ENABLED // HLSL Change - don't build vectorization passes
#include "llvm/Transforms/Vectorize.h"
#include "llvm-c/Initialization.h"
#include "llvm-c/Transforms/Vectorize.h"
#include "llvm/Analysis/Passes.h"
#include "llvm/IR/Verifier.h"
#include "llvm/InitializePasses.h"
#include "llvm/IR/LegacyPassManager.h"
using namespace llvm;
/// initializeVectorizationPasses - Initialize all passes linked into the
/// Vectorization library.
void llvm::initializeVectorization(PassRegistry &Registry) {
initializeBBVectorizePass(Registry);
initializeLoopVectorizePass(Registry);
initializeSLPVectorizerPass(Registry);
}
void LLVMInitializeVectorization(LLVMPassRegistryRef R) {
initializeVectorization(*unwrap(R));
}
void LLVMAddBBVectorizePass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createBBVectorizePass());
}
void LLVMAddLoopVectorizePass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createLoopVectorizePass());
}
void LLVMAddSLPVectorizePass(LLVMPassManagerRef PM) {
unwrap(PM)->add(createSLPVectorizerPass());
}
#else
namespace llvm {
class PassRegistry;
void initializeVectorization(PassRegistry &) {}
}
#endif // HLSL Change - don't build vectorization passes
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/LLVMContextImpl.h | //===-- LLVMContextImpl.h - The LLVMContextImpl opaque class ----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file declares LLVMContextImpl, the opaque implementation
// of LLVMContext.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_IR_LLVMCONTEXTIMPL_H
#define LLVM_LIB_IR_LLVMCONTEXTIMPL_H
#include "AttributeImpl.h"
#include "ConstantsContext.h"
#include "llvm/ADT/APFloat.h"
#include "llvm/ADT/APInt.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/FoldingSet.h"
#include "llvm/ADT/Hashing.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DebugInfoMetadata.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/ValueHandle.h"
#include <vector>
namespace llvm {
class ConstantInt;
class ConstantFP;
class DiagnosticInfoOptimizationRemark;
class DiagnosticInfoOptimizationRemarkMissed;
class DiagnosticInfoOptimizationRemarkAnalysis;
class GCStrategy;
class LLVMContext;
class Type;
class Value;
struct DenseMapAPIntKeyInfo {
static inline APInt getEmptyKey() {
APInt V(nullptr, 0);
V.VAL = 0;
return V;
}
static inline APInt getTombstoneKey() {
APInt V(nullptr, 0);
V.VAL = 1;
return V;
}
static unsigned getHashValue(const APInt &Key) {
return static_cast<unsigned>(hash_value(Key));
}
static bool isEqual(const APInt &LHS, const APInt &RHS) {
return LHS.getBitWidth() == RHS.getBitWidth() && LHS == RHS;
}
};
struct DenseMapAPFloatKeyInfo {
static inline APFloat getEmptyKey() { return APFloat(APFloat::Bogus, 1); }
static inline APFloat getTombstoneKey() { return APFloat(APFloat::Bogus, 2); }
static unsigned getHashValue(const APFloat &Key) {
return static_cast<unsigned>(hash_value(Key));
}
static bool isEqual(const APFloat &LHS, const APFloat &RHS) {
return LHS.bitwiseIsEqual(RHS);
}
};
struct AnonStructTypeKeyInfo {
struct KeyTy {
ArrayRef<Type*> ETypes;
bool isPacked;
KeyTy(const ArrayRef<Type*>& E, bool P) :
ETypes(E), isPacked(P) {}
KeyTy(const StructType *ST)
: ETypes(ST->elements()), isPacked(ST->isPacked()) {}
bool operator==(const KeyTy& that) const {
if (isPacked != that.isPacked)
return false;
if (ETypes != that.ETypes)
return false;
return true;
}
bool operator!=(const KeyTy& that) const {
return !this->operator==(that);
}
};
static inline StructType* getEmptyKey() {
return DenseMapInfo<StructType*>::getEmptyKey();
}
static inline StructType* getTombstoneKey() {
return DenseMapInfo<StructType*>::getTombstoneKey();
}
static unsigned getHashValue(const KeyTy& Key) {
return hash_combine(hash_combine_range(Key.ETypes.begin(),
Key.ETypes.end()),
Key.isPacked);
}
static unsigned getHashValue(const StructType *ST) {
return getHashValue(KeyTy(ST));
}
static bool isEqual(const KeyTy& LHS, const StructType *RHS) {
if (RHS == getEmptyKey() || RHS == getTombstoneKey())
return false;
return LHS == KeyTy(RHS);
}
static bool isEqual(const StructType *LHS, const StructType *RHS) {
return LHS == RHS;
}
};
struct FunctionTypeKeyInfo {
struct KeyTy {
const Type *ReturnType;
ArrayRef<Type*> Params;
bool isVarArg;
KeyTy(const Type* R, const ArrayRef<Type*>& P, bool V) :
ReturnType(R), Params(P), isVarArg(V) {}
KeyTy(const FunctionType *FT)
: ReturnType(FT->getReturnType()), Params(FT->params()),
isVarArg(FT->isVarArg()) {}
bool operator==(const KeyTy& that) const {
if (ReturnType != that.ReturnType)
return false;
if (isVarArg != that.isVarArg)
return false;
if (Params != that.Params)
return false;
return true;
}
bool operator!=(const KeyTy& that) const {
return !this->operator==(that);
}
};
static inline FunctionType* getEmptyKey() {
return DenseMapInfo<FunctionType*>::getEmptyKey();
}
static inline FunctionType* getTombstoneKey() {
return DenseMapInfo<FunctionType*>::getTombstoneKey();
}
static unsigned getHashValue(const KeyTy& Key) {
return hash_combine(Key.ReturnType,
hash_combine_range(Key.Params.begin(),
Key.Params.end()),
Key.isVarArg);
}
static unsigned getHashValue(const FunctionType *FT) {
return getHashValue(KeyTy(FT));
}
static bool isEqual(const KeyTy& LHS, const FunctionType *RHS) {
if (RHS == getEmptyKey() || RHS == getTombstoneKey())
return false;
return LHS == KeyTy(RHS);
}
static bool isEqual(const FunctionType *LHS, const FunctionType *RHS) {
return LHS == RHS;
}
};
/// \brief Structure for hashing arbitrary MDNode operands.
class MDNodeOpsKey {
ArrayRef<Metadata *> RawOps;
ArrayRef<MDOperand> Ops;
unsigned Hash;
protected:
MDNodeOpsKey(ArrayRef<Metadata *> Ops)
: RawOps(Ops), Hash(calculateHash(Ops)) {}
template <class NodeTy>
MDNodeOpsKey(const NodeTy *N, unsigned Offset = 0)
: Ops(N->op_begin() + Offset, N->op_end()), Hash(N->getHash()) {}
template <class NodeTy>
bool compareOps(const NodeTy *RHS, unsigned Offset = 0) const {
if (getHash() != RHS->getHash())
return false;
assert((RawOps.empty() || Ops.empty()) && "Two sets of operands?");
return RawOps.empty() ? compareOps(Ops, RHS, Offset)
: compareOps(RawOps, RHS, Offset);
}
static unsigned calculateHash(MDNode *N, unsigned Offset = 0);
private:
template <class T>
static bool compareOps(ArrayRef<T> Ops, const MDNode *RHS, unsigned Offset) {
if (Ops.size() != RHS->getNumOperands() - Offset)
return false;
return std::equal(Ops.begin(), Ops.end(), RHS->op_begin() + Offset);
}
static unsigned calculateHash(ArrayRef<Metadata *> Ops);
public:
unsigned getHash() const { return Hash; }
};
template <class NodeTy> struct MDNodeKeyImpl;
template <class NodeTy> struct MDNodeInfo;
/// \brief DenseMapInfo for MDTuple.
///
/// Note that we don't need the is-function-local bit, since that's implicit in
/// the operands.
template <> struct MDNodeKeyImpl<MDTuple> : MDNodeOpsKey {
MDNodeKeyImpl(ArrayRef<Metadata *> Ops) : MDNodeOpsKey(Ops) {}
MDNodeKeyImpl(const MDTuple *N) : MDNodeOpsKey(N) {}
bool isKeyOf(const MDTuple *RHS) const { return compareOps(RHS); }
unsigned getHashValue() const { return getHash(); }
static unsigned calculateHash(MDTuple *N) {
return MDNodeOpsKey::calculateHash(N);
}
};
/// \brief DenseMapInfo for DILocation.
template <> struct MDNodeKeyImpl<DILocation> {
unsigned Line;
unsigned Column;
Metadata *Scope;
Metadata *InlinedAt;
MDNodeKeyImpl(unsigned Line, unsigned Column, Metadata *Scope,
Metadata *InlinedAt)
: Line(Line), Column(Column), Scope(Scope), InlinedAt(InlinedAt) {}
MDNodeKeyImpl(const DILocation *L)
: Line(L->getLine()), Column(L->getColumn()), Scope(L->getRawScope()),
InlinedAt(L->getRawInlinedAt()) {}
bool isKeyOf(const DILocation *RHS) const {
return Line == RHS->getLine() && Column == RHS->getColumn() &&
Scope == RHS->getRawScope() && InlinedAt == RHS->getRawInlinedAt();
}
unsigned getHashValue() const {
return hash_combine(Line, Column, Scope, InlinedAt);
}
};
/// \brief DenseMapInfo for GenericDINode.
template <> struct MDNodeKeyImpl<GenericDINode> : MDNodeOpsKey {
unsigned Tag;
StringRef Header;
MDNodeKeyImpl(unsigned Tag, StringRef Header, ArrayRef<Metadata *> DwarfOps)
: MDNodeOpsKey(DwarfOps), Tag(Tag), Header(Header) {}
MDNodeKeyImpl(const GenericDINode *N)
: MDNodeOpsKey(N, 1), Tag(N->getTag()), Header(N->getHeader()) {}
bool isKeyOf(const GenericDINode *RHS) const {
return Tag == RHS->getTag() && Header == RHS->getHeader() &&
compareOps(RHS, 1);
}
unsigned getHashValue() const { return hash_combine(getHash(), Tag, Header); }
static unsigned calculateHash(GenericDINode *N) {
return MDNodeOpsKey::calculateHash(N, 1);
}
};
template <> struct MDNodeKeyImpl<DISubrange> {
int64_t Count;
int64_t LowerBound;
MDNodeKeyImpl(int64_t Count, int64_t LowerBound)
: Count(Count), LowerBound(LowerBound) {}
MDNodeKeyImpl(const DISubrange *N)
: Count(N->getCount()), LowerBound(N->getLowerBound()) {}
bool isKeyOf(const DISubrange *RHS) const {
return Count == RHS->getCount() && LowerBound == RHS->getLowerBound();
}
unsigned getHashValue() const { return hash_combine(Count, LowerBound); }
};
template <> struct MDNodeKeyImpl<DIEnumerator> {
int64_t Value;
StringRef Name;
MDNodeKeyImpl(int64_t Value, StringRef Name) : Value(Value), Name(Name) {}
MDNodeKeyImpl(const DIEnumerator *N)
: Value(N->getValue()), Name(N->getName()) {}
bool isKeyOf(const DIEnumerator *RHS) const {
return Value == RHS->getValue() && Name == RHS->getName();
}
unsigned getHashValue() const { return hash_combine(Value, Name); }
};
template <> struct MDNodeKeyImpl<DIBasicType> {
unsigned Tag;
StringRef Name;
uint64_t SizeInBits;
uint64_t AlignInBits;
unsigned Encoding;
MDNodeKeyImpl(unsigned Tag, StringRef Name, uint64_t SizeInBits,
uint64_t AlignInBits, unsigned Encoding)
: Tag(Tag), Name(Name), SizeInBits(SizeInBits), AlignInBits(AlignInBits),
Encoding(Encoding) {}
MDNodeKeyImpl(const DIBasicType *N)
: Tag(N->getTag()), Name(N->getName()), SizeInBits(N->getSizeInBits()),
AlignInBits(N->getAlignInBits()), Encoding(N->getEncoding()) {}
bool isKeyOf(const DIBasicType *RHS) const {
return Tag == RHS->getTag() && Name == RHS->getName() &&
SizeInBits == RHS->getSizeInBits() &&
AlignInBits == RHS->getAlignInBits() &&
Encoding == RHS->getEncoding();
}
unsigned getHashValue() const {
return hash_combine(Tag, Name, SizeInBits, AlignInBits, Encoding);
}
};
template <> struct MDNodeKeyImpl<DIDerivedType> {
unsigned Tag;
StringRef Name;
Metadata *File;
unsigned Line;
Metadata *Scope;
Metadata *BaseType;
uint64_t SizeInBits;
uint64_t AlignInBits;
uint64_t OffsetInBits;
unsigned Flags;
Metadata *ExtraData;
MDNodeKeyImpl(unsigned Tag, StringRef Name, Metadata *File, unsigned Line,
Metadata *Scope, Metadata *BaseType, uint64_t SizeInBits,
uint64_t AlignInBits, uint64_t OffsetInBits, unsigned Flags,
Metadata *ExtraData)
: Tag(Tag), Name(Name), File(File), Line(Line), Scope(Scope),
BaseType(BaseType), SizeInBits(SizeInBits), AlignInBits(AlignInBits),
OffsetInBits(OffsetInBits), Flags(Flags), ExtraData(ExtraData) {}
MDNodeKeyImpl(const DIDerivedType *N)
: Tag(N->getTag()), Name(N->getName()), File(N->getRawFile()),
Line(N->getLine()), Scope(N->getRawScope()),
BaseType(N->getRawBaseType()), SizeInBits(N->getSizeInBits()),
AlignInBits(N->getAlignInBits()), OffsetInBits(N->getOffsetInBits()),
Flags(N->getFlags()), ExtraData(N->getRawExtraData()) {}
bool isKeyOf(const DIDerivedType *RHS) const {
return Tag == RHS->getTag() && Name == RHS->getName() &&
File == RHS->getRawFile() && Line == RHS->getLine() &&
Scope == RHS->getRawScope() && BaseType == RHS->getRawBaseType() &&
SizeInBits == RHS->getSizeInBits() &&
AlignInBits == RHS->getAlignInBits() &&
OffsetInBits == RHS->getOffsetInBits() && Flags == RHS->getFlags() &&
ExtraData == RHS->getRawExtraData();
}
unsigned getHashValue() const {
return hash_combine(Tag, Name, File, Line, Scope, BaseType, SizeInBits,
AlignInBits, OffsetInBits, Flags, ExtraData);
}
};
template <> struct MDNodeKeyImpl<DICompositeType> {
unsigned Tag;
StringRef Name;
Metadata *File;
unsigned Line;
Metadata *Scope;
Metadata *BaseType;
uint64_t SizeInBits;
uint64_t AlignInBits;
uint64_t OffsetInBits;
unsigned Flags;
Metadata *Elements;
unsigned RuntimeLang;
Metadata *VTableHolder;
Metadata *TemplateParams;
StringRef Identifier;
MDNodeKeyImpl(unsigned Tag, StringRef Name, Metadata *File, unsigned Line,
Metadata *Scope, Metadata *BaseType, uint64_t SizeInBits,
uint64_t AlignInBits, uint64_t OffsetInBits, unsigned Flags,
Metadata *Elements, unsigned RuntimeLang,
Metadata *VTableHolder, Metadata *TemplateParams,
StringRef Identifier)
: Tag(Tag), Name(Name), File(File), Line(Line), Scope(Scope),
BaseType(BaseType), SizeInBits(SizeInBits), AlignInBits(AlignInBits),
OffsetInBits(OffsetInBits), Flags(Flags), Elements(Elements),
RuntimeLang(RuntimeLang), VTableHolder(VTableHolder),
TemplateParams(TemplateParams), Identifier(Identifier) {}
MDNodeKeyImpl(const DICompositeType *N)
: Tag(N->getTag()), Name(N->getName()), File(N->getRawFile()),
Line(N->getLine()), Scope(N->getRawScope()),
BaseType(N->getRawBaseType()), SizeInBits(N->getSizeInBits()),
AlignInBits(N->getAlignInBits()), OffsetInBits(N->getOffsetInBits()),
Flags(N->getFlags()), Elements(N->getRawElements()),
RuntimeLang(N->getRuntimeLang()), VTableHolder(N->getRawVTableHolder()),
TemplateParams(N->getRawTemplateParams()),
Identifier(N->getIdentifier()) {}
bool isKeyOf(const DICompositeType *RHS) const {
return Tag == RHS->getTag() && Name == RHS->getName() &&
File == RHS->getRawFile() && Line == RHS->getLine() &&
Scope == RHS->getRawScope() && BaseType == RHS->getRawBaseType() &&
SizeInBits == RHS->getSizeInBits() &&
AlignInBits == RHS->getAlignInBits() &&
OffsetInBits == RHS->getOffsetInBits() && Flags == RHS->getFlags() &&
Elements == RHS->getRawElements() &&
RuntimeLang == RHS->getRuntimeLang() &&
VTableHolder == RHS->getRawVTableHolder() &&
TemplateParams == RHS->getRawTemplateParams() &&
Identifier == RHS->getIdentifier();
}
unsigned getHashValue() const {
return hash_combine(Tag, Name, File, Line, Scope, BaseType, SizeInBits,
AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang,
VTableHolder, TemplateParams, Identifier);
}
};
template <> struct MDNodeKeyImpl<DISubroutineType> {
unsigned Flags;
Metadata *TypeArray;
MDNodeKeyImpl(int64_t Flags, Metadata *TypeArray)
: Flags(Flags), TypeArray(TypeArray) {}
MDNodeKeyImpl(const DISubroutineType *N)
: Flags(N->getFlags()), TypeArray(N->getRawTypeArray()) {}
bool isKeyOf(const DISubroutineType *RHS) const {
return Flags == RHS->getFlags() && TypeArray == RHS->getRawTypeArray();
}
unsigned getHashValue() const { return hash_combine(Flags, TypeArray); }
};
template <> struct MDNodeKeyImpl<DIFile> {
StringRef Filename;
StringRef Directory;
MDNodeKeyImpl(StringRef Filename, StringRef Directory)
: Filename(Filename), Directory(Directory) {}
MDNodeKeyImpl(const DIFile *N)
: Filename(N->getFilename()), Directory(N->getDirectory()) {}
bool isKeyOf(const DIFile *RHS) const {
return Filename == RHS->getFilename() && Directory == RHS->getDirectory();
}
unsigned getHashValue() const { return hash_combine(Filename, Directory); }
};
template <> struct MDNodeKeyImpl<DICompileUnit> {
unsigned SourceLanguage;
Metadata *File;
StringRef Producer;
bool IsOptimized;
StringRef Flags;
unsigned RuntimeVersion;
StringRef SplitDebugFilename;
unsigned EmissionKind;
Metadata *EnumTypes;
Metadata *RetainedTypes;
Metadata *Subprograms;
Metadata *GlobalVariables;
Metadata *ImportedEntities;
uint64_t DWOId;
MDNodeKeyImpl(unsigned SourceLanguage, Metadata *File, StringRef Producer,
bool IsOptimized, StringRef Flags, unsigned RuntimeVersion,
StringRef SplitDebugFilename, unsigned EmissionKind,
Metadata *EnumTypes, Metadata *RetainedTypes,
Metadata *Subprograms, Metadata *GlobalVariables,
Metadata *ImportedEntities, uint64_t DWOId)
: SourceLanguage(SourceLanguage), File(File), Producer(Producer),
IsOptimized(IsOptimized), Flags(Flags), RuntimeVersion(RuntimeVersion),
SplitDebugFilename(SplitDebugFilename), EmissionKind(EmissionKind),
EnumTypes(EnumTypes), RetainedTypes(RetainedTypes),
Subprograms(Subprograms), GlobalVariables(GlobalVariables),
ImportedEntities(ImportedEntities), DWOId(DWOId) {}
MDNodeKeyImpl(const DICompileUnit *N)
: SourceLanguage(N->getSourceLanguage()), File(N->getRawFile()),
Producer(N->getProducer()), IsOptimized(N->isOptimized()),
Flags(N->getFlags()), RuntimeVersion(N->getRuntimeVersion()),
SplitDebugFilename(N->getSplitDebugFilename()),
EmissionKind(N->getEmissionKind()), EnumTypes(N->getRawEnumTypes()),
RetainedTypes(N->getRawRetainedTypes()),
Subprograms(N->getRawSubprograms()),
GlobalVariables(N->getRawGlobalVariables()),
ImportedEntities(N->getRawImportedEntities()), DWOId(N->getDWOId()) {}
bool isKeyOf(const DICompileUnit *RHS) const {
return SourceLanguage == RHS->getSourceLanguage() &&
File == RHS->getRawFile() && Producer == RHS->getProducer() &&
IsOptimized == RHS->isOptimized() && Flags == RHS->getFlags() &&
RuntimeVersion == RHS->getRuntimeVersion() &&
SplitDebugFilename == RHS->getSplitDebugFilename() &&
EmissionKind == RHS->getEmissionKind() &&
EnumTypes == RHS->getRawEnumTypes() &&
RetainedTypes == RHS->getRawRetainedTypes() &&
Subprograms == RHS->getRawSubprograms() &&
GlobalVariables == RHS->getRawGlobalVariables() &&
ImportedEntities == RHS->getRawImportedEntities() &&
DWOId == RHS->getDWOId();
}
unsigned getHashValue() const {
return hash_combine(SourceLanguage, File, Producer, IsOptimized, Flags,
RuntimeVersion, SplitDebugFilename, EmissionKind,
EnumTypes, RetainedTypes, Subprograms, GlobalVariables,
ImportedEntities, DWOId);
}
};
template <> struct MDNodeKeyImpl<DISubprogram> {
Metadata *Scope;
StringRef Name;
StringRef LinkageName;
Metadata *File;
unsigned Line;
Metadata *Type;
bool IsLocalToUnit;
bool IsDefinition;
unsigned ScopeLine;
Metadata *ContainingType;
unsigned Virtuality;
unsigned VirtualIndex;
unsigned Flags;
bool IsOptimized;
Metadata *Function;
Metadata *TemplateParams;
Metadata *Declaration;
Metadata *Variables;
MDNodeKeyImpl(Metadata *Scope, StringRef Name, StringRef LinkageName,
Metadata *File, unsigned Line, Metadata *Type,
bool IsLocalToUnit, bool IsDefinition, unsigned ScopeLine,
Metadata *ContainingType, unsigned Virtuality,
unsigned VirtualIndex, unsigned Flags, bool IsOptimized,
Metadata *Function, Metadata *TemplateParams,
Metadata *Declaration, Metadata *Variables)
: Scope(Scope), Name(Name), LinkageName(LinkageName), File(File),
Line(Line), Type(Type), IsLocalToUnit(IsLocalToUnit),
IsDefinition(IsDefinition), ScopeLine(ScopeLine),
ContainingType(ContainingType), Virtuality(Virtuality),
VirtualIndex(VirtualIndex), Flags(Flags), IsOptimized(IsOptimized),
Function(Function), TemplateParams(TemplateParams),
Declaration(Declaration), Variables(Variables) {}
MDNodeKeyImpl(const DISubprogram *N)
: Scope(N->getRawScope()), Name(N->getName()),
LinkageName(N->getLinkageName()), File(N->getRawFile()),
Line(N->getLine()), Type(N->getRawType()),
IsLocalToUnit(N->isLocalToUnit()), IsDefinition(N->isDefinition()),
ScopeLine(N->getScopeLine()), ContainingType(N->getRawContainingType()),
Virtuality(N->getVirtuality()), VirtualIndex(N->getVirtualIndex()),
Flags(N->getFlags()), IsOptimized(N->isOptimized()),
Function(N->getRawFunction()),
TemplateParams(N->getRawTemplateParams()),
Declaration(N->getRawDeclaration()), Variables(N->getRawVariables()) {}
bool isKeyOf(const DISubprogram *RHS) const {
return Scope == RHS->getRawScope() && Name == RHS->getName() &&
LinkageName == RHS->getLinkageName() && File == RHS->getRawFile() &&
Line == RHS->getLine() && Type == RHS->getRawType() &&
IsLocalToUnit == RHS->isLocalToUnit() &&
IsDefinition == RHS->isDefinition() &&
ScopeLine == RHS->getScopeLine() &&
ContainingType == RHS->getRawContainingType() &&
Virtuality == RHS->getVirtuality() &&
VirtualIndex == RHS->getVirtualIndex() && Flags == RHS->getFlags() &&
IsOptimized == RHS->isOptimized() &&
Function == RHS->getRawFunction() &&
TemplateParams == RHS->getRawTemplateParams() &&
Declaration == RHS->getRawDeclaration() &&
Variables == RHS->getRawVariables();
}
unsigned getHashValue() const {
return hash_combine(Scope, Name, LinkageName, File, Line, Type,
IsLocalToUnit, IsDefinition, ScopeLine, ContainingType,
Virtuality, VirtualIndex, Flags, IsOptimized, Function,
TemplateParams, Declaration, Variables);
}
};
template <> struct MDNodeKeyImpl<DILexicalBlock> {
Metadata *Scope;
Metadata *File;
unsigned Line;
unsigned Column;
MDNodeKeyImpl(Metadata *Scope, Metadata *File, unsigned Line, unsigned Column)
: Scope(Scope), File(File), Line(Line), Column(Column) {}
MDNodeKeyImpl(const DILexicalBlock *N)
: Scope(N->getRawScope()), File(N->getRawFile()), Line(N->getLine()),
Column(N->getColumn()) {}
bool isKeyOf(const DILexicalBlock *RHS) const {
return Scope == RHS->getRawScope() && File == RHS->getRawFile() &&
Line == RHS->getLine() && Column == RHS->getColumn();
}
unsigned getHashValue() const {
return hash_combine(Scope, File, Line, Column);
}
};
template <> struct MDNodeKeyImpl<DILexicalBlockFile> {
Metadata *Scope;
Metadata *File;
unsigned Discriminator;
MDNodeKeyImpl(Metadata *Scope, Metadata *File, unsigned Discriminator)
: Scope(Scope), File(File), Discriminator(Discriminator) {}
MDNodeKeyImpl(const DILexicalBlockFile *N)
: Scope(N->getRawScope()), File(N->getRawFile()),
Discriminator(N->getDiscriminator()) {}
bool isKeyOf(const DILexicalBlockFile *RHS) const {
return Scope == RHS->getRawScope() && File == RHS->getRawFile() &&
Discriminator == RHS->getDiscriminator();
}
unsigned getHashValue() const {
return hash_combine(Scope, File, Discriminator);
}
};
template <> struct MDNodeKeyImpl<DINamespace> {
Metadata *Scope;
Metadata *File;
StringRef Name;
unsigned Line;
MDNodeKeyImpl(Metadata *Scope, Metadata *File, StringRef Name, unsigned Line)
: Scope(Scope), File(File), Name(Name), Line(Line) {}
MDNodeKeyImpl(const DINamespace *N)
: Scope(N->getRawScope()), File(N->getRawFile()), Name(N->getName()),
Line(N->getLine()) {}
bool isKeyOf(const DINamespace *RHS) const {
return Scope == RHS->getRawScope() && File == RHS->getRawFile() &&
Name == RHS->getName() && Line == RHS->getLine();
}
unsigned getHashValue() const {
return hash_combine(Scope, File, Name, Line);
}
};
template <> struct MDNodeKeyImpl<DIModule> {
Metadata *Scope;
StringRef Name;
StringRef ConfigurationMacros;
StringRef IncludePath;
StringRef ISysRoot;
MDNodeKeyImpl(Metadata *Scope, StringRef Name,
StringRef ConfigurationMacros,
StringRef IncludePath,
StringRef ISysRoot)
: Scope(Scope), Name(Name), ConfigurationMacros(ConfigurationMacros),
IncludePath(IncludePath), ISysRoot(ISysRoot) {}
MDNodeKeyImpl(const DIModule *N)
: Scope(N->getRawScope()), Name(N->getName()),
ConfigurationMacros(N->getConfigurationMacros()),
IncludePath(N->getIncludePath()), ISysRoot(N->getISysRoot()) {}
bool isKeyOf(const DIModule *RHS) const {
return Scope == RHS->getRawScope() && Name == RHS->getName() &&
ConfigurationMacros == RHS->getConfigurationMacros() &&
IncludePath == RHS->getIncludePath() &&
ISysRoot == RHS->getISysRoot();
}
unsigned getHashValue() const {
return hash_combine(Scope, Name,
ConfigurationMacros, IncludePath, ISysRoot);
}
};
template <> struct MDNodeKeyImpl<DITemplateTypeParameter> {
StringRef Name;
Metadata *Type;
MDNodeKeyImpl(StringRef Name, Metadata *Type) : Name(Name), Type(Type) {}
MDNodeKeyImpl(const DITemplateTypeParameter *N)
: Name(N->getName()), Type(N->getRawType()) {}
bool isKeyOf(const DITemplateTypeParameter *RHS) const {
return Name == RHS->getName() && Type == RHS->getRawType();
}
unsigned getHashValue() const { return hash_combine(Name, Type); }
};
template <> struct MDNodeKeyImpl<DITemplateValueParameter> {
unsigned Tag;
StringRef Name;
Metadata *Type;
Metadata *Value;
MDNodeKeyImpl(unsigned Tag, StringRef Name, Metadata *Type, Metadata *Value)
: Tag(Tag), Name(Name), Type(Type), Value(Value) {}
MDNodeKeyImpl(const DITemplateValueParameter *N)
: Tag(N->getTag()), Name(N->getName()), Type(N->getRawType()),
Value(N->getValue()) {}
bool isKeyOf(const DITemplateValueParameter *RHS) const {
return Tag == RHS->getTag() && Name == RHS->getName() &&
Type == RHS->getRawType() && Value == RHS->getValue();
}
unsigned getHashValue() const { return hash_combine(Tag, Name, Type, Value); }
};
template <> struct MDNodeKeyImpl<DIGlobalVariable> {
Metadata *Scope;
StringRef Name;
StringRef LinkageName;
Metadata *File;
unsigned Line;
Metadata *Type;
bool IsLocalToUnit;
bool IsDefinition;
Metadata *Variable;
Metadata *StaticDataMemberDeclaration;
MDNodeKeyImpl(Metadata *Scope, StringRef Name, StringRef LinkageName,
Metadata *File, unsigned Line, Metadata *Type,
bool IsLocalToUnit, bool IsDefinition, Metadata *Variable,
Metadata *StaticDataMemberDeclaration)
: Scope(Scope), Name(Name), LinkageName(LinkageName), File(File),
Line(Line), Type(Type), IsLocalToUnit(IsLocalToUnit),
IsDefinition(IsDefinition), Variable(Variable),
StaticDataMemberDeclaration(StaticDataMemberDeclaration) {}
MDNodeKeyImpl(const DIGlobalVariable *N)
: Scope(N->getRawScope()), Name(N->getName()),
LinkageName(N->getLinkageName()), File(N->getRawFile()),
Line(N->getLine()), Type(N->getRawType()),
IsLocalToUnit(N->isLocalToUnit()), IsDefinition(N->isDefinition()),
Variable(N->getRawVariable()),
StaticDataMemberDeclaration(N->getRawStaticDataMemberDeclaration()) {}
bool isKeyOf(const DIGlobalVariable *RHS) const {
return Scope == RHS->getRawScope() && Name == RHS->getName() &&
LinkageName == RHS->getLinkageName() && File == RHS->getRawFile() &&
Line == RHS->getLine() && Type == RHS->getRawType() &&
IsLocalToUnit == RHS->isLocalToUnit() &&
IsDefinition == RHS->isDefinition() &&
Variable == RHS->getRawVariable() &&
StaticDataMemberDeclaration ==
RHS->getRawStaticDataMemberDeclaration();
}
unsigned getHashValue() const {
return hash_combine(Scope, Name, LinkageName, File, Line, Type,
IsLocalToUnit, IsDefinition, Variable,
StaticDataMemberDeclaration);
}
};
template <> struct MDNodeKeyImpl<DILocalVariable> {
unsigned Tag;
Metadata *Scope;
StringRef Name;
Metadata *File;
unsigned Line;
Metadata *Type;
unsigned Arg;
unsigned Flags;
MDNodeKeyImpl(unsigned Tag, Metadata *Scope, StringRef Name, Metadata *File,
unsigned Line, Metadata *Type, unsigned Arg, unsigned Flags)
: Tag(Tag), Scope(Scope), Name(Name), File(File), Line(Line), Type(Type),
Arg(Arg), Flags(Flags) {}
MDNodeKeyImpl(const DILocalVariable *N)
: Tag(N->getTag()), Scope(N->getRawScope()), Name(N->getName()),
File(N->getRawFile()), Line(N->getLine()), Type(N->getRawType()),
Arg(N->getArg()), Flags(N->getFlags()) {}
bool isKeyOf(const DILocalVariable *RHS) const {
return Tag == RHS->getTag() && Scope == RHS->getRawScope() &&
Name == RHS->getName() && File == RHS->getRawFile() &&
Line == RHS->getLine() && Type == RHS->getRawType() &&
Arg == RHS->getArg() && Flags == RHS->getFlags();
}
unsigned getHashValue() const {
return hash_combine(Tag, Scope, Name, File, Line, Type, Arg, Flags);
}
};
template <> struct MDNodeKeyImpl<DIExpression> {
ArrayRef<uint64_t> Elements;
MDNodeKeyImpl(ArrayRef<uint64_t> Elements) : Elements(Elements) {}
MDNodeKeyImpl(const DIExpression *N) : Elements(N->getElements()) {}
bool isKeyOf(const DIExpression *RHS) const {
return Elements == RHS->getElements();
}
unsigned getHashValue() const {
return hash_combine_range(Elements.begin(), Elements.end());
}
};
template <> struct MDNodeKeyImpl<DIObjCProperty> {
StringRef Name;
Metadata *File;
unsigned Line;
StringRef GetterName;
StringRef SetterName;
unsigned Attributes;
Metadata *Type;
MDNodeKeyImpl(StringRef Name, Metadata *File, unsigned Line,
StringRef GetterName, StringRef SetterName, unsigned Attributes,
Metadata *Type)
: Name(Name), File(File), Line(Line), GetterName(GetterName),
SetterName(SetterName), Attributes(Attributes), Type(Type) {}
MDNodeKeyImpl(const DIObjCProperty *N)
: Name(N->getName()), File(N->getRawFile()), Line(N->getLine()),
GetterName(N->getGetterName()), SetterName(N->getSetterName()),
Attributes(N->getAttributes()), Type(N->getRawType()) {}
bool isKeyOf(const DIObjCProperty *RHS) const {
return Name == RHS->getName() && File == RHS->getRawFile() &&
Line == RHS->getLine() && GetterName == RHS->getGetterName() &&
SetterName == RHS->getSetterName() &&
Attributes == RHS->getAttributes() && Type == RHS->getRawType();
}
unsigned getHashValue() const {
return hash_combine(Name, File, Line, GetterName, SetterName, Attributes,
Type);
}
};
template <> struct MDNodeKeyImpl<DIImportedEntity> {
unsigned Tag;
Metadata *Scope;
Metadata *Entity;
unsigned Line;
StringRef Name;
MDNodeKeyImpl(unsigned Tag, Metadata *Scope, Metadata *Entity, unsigned Line,
StringRef Name)
: Tag(Tag), Scope(Scope), Entity(Entity), Line(Line), Name(Name) {}
MDNodeKeyImpl(const DIImportedEntity *N)
: Tag(N->getTag()), Scope(N->getRawScope()), Entity(N->getRawEntity()),
Line(N->getLine()), Name(N->getName()) {}
bool isKeyOf(const DIImportedEntity *RHS) const {
return Tag == RHS->getTag() && Scope == RHS->getRawScope() &&
Entity == RHS->getRawEntity() && Line == RHS->getLine() &&
Name == RHS->getName();
}
unsigned getHashValue() const {
return hash_combine(Tag, Scope, Entity, Line, Name);
}
};
/// \brief DenseMapInfo for MDNode subclasses.
template <class NodeTy> struct MDNodeInfo {
typedef MDNodeKeyImpl<NodeTy> KeyTy;
static inline NodeTy *getEmptyKey() {
return DenseMapInfo<NodeTy *>::getEmptyKey();
}
static inline NodeTy *getTombstoneKey() {
return DenseMapInfo<NodeTy *>::getTombstoneKey();
}
static unsigned getHashValue(const KeyTy &Key) { return Key.getHashValue(); }
static unsigned getHashValue(const NodeTy *N) {
return KeyTy(N).getHashValue();
}
static bool isEqual(const KeyTy &LHS, const NodeTy *RHS) {
if (RHS == getEmptyKey() || RHS == getTombstoneKey())
return false;
return LHS.isKeyOf(RHS);
}
static bool isEqual(const NodeTy *LHS, const NodeTy *RHS) {
return LHS == RHS;
}
};
#define HANDLE_MDNODE_LEAF(CLASS) typedef MDNodeInfo<CLASS> CLASS##Info;
#include "llvm/IR/Metadata.def"
/// \brief Map-like storage for metadata attachments.
class MDAttachmentMap {
SmallVector<std::pair<unsigned, TrackingMDNodeRef>, 2> Attachments;
public:
bool empty() const { return Attachments.empty(); }
size_t size() const { return Attachments.size(); }
/// \brief Get a particular attachment (if any).
MDNode *lookup(unsigned ID) const;
/// \brief Set an attachment to a particular node.
///
/// Set the \c ID attachment to \c MD, replacing the current attachment at \c
/// ID (if anyway).
void set(unsigned ID, MDNode &MD);
/// \brief Remove an attachment.
///
/// Remove the attachment at \c ID, if any.
void erase(unsigned ID);
/// \brief Copy out all the attachments.
///
/// Copies all the current attachments into \c Result, sorting by attachment
/// ID. This function does \em not clear \c Result.
void getAll(SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const;
/// \brief Erase matching attachments.
///
/// Erases all attachments matching the \c shouldRemove predicate.
template <class PredTy> void remove_if(PredTy shouldRemove) {
Attachments.erase(
std::remove_if(Attachments.begin(), Attachments.end(), shouldRemove),
Attachments.end());
}
};
class LLVMContextImpl {
public:
/// OwnedModules - The set of modules instantiated in this context, and which
/// will be automatically deleted if this context is deleted.
SmallPtrSet<Module*, 4> OwnedModules;
LLVMContext::InlineAsmDiagHandlerTy InlineAsmDiagHandler;
void *InlineAsmDiagContext;
LLVMContext::DiagnosticHandlerTy DiagnosticHandler;
void *DiagnosticContext;
bool RespectDiagnosticFilters;
LLVMContext::YieldCallbackTy YieldCallback;
void *YieldOpaqueHandle;
typedef DenseMap<APInt, ConstantInt *, DenseMapAPIntKeyInfo> IntMapTy;
IntMapTy IntConstants;
typedef DenseMap<APFloat, ConstantFP *, DenseMapAPFloatKeyInfo> FPMapTy;
FPMapTy FPConstants;
FoldingSet<AttributeImpl> AttrsSet;
FoldingSet<AttributeSetImpl> AttrsLists;
FoldingSet<AttributeSetNode> AttrsSetNodes;
StringMap<MDString> MDStringCache;
DenseMap<Value *, ValueAsMetadata *> ValuesAsMetadata;
DenseMap<Metadata *, MetadataAsValue *> MetadataAsValues;
DenseMap<const Value*, ValueName*> ValueNames;
#define HANDLE_MDNODE_LEAF(CLASS) DenseSet<CLASS *, CLASS##Info> CLASS##s;
#include "llvm/IR/Metadata.def"
// MDNodes may be uniqued or not uniqued. When they're not uniqued, they
// aren't in the MDNodeSet, but they're still shared between objects, so no
// one object can destroy them. This set allows us to at least destroy them
// on Context destruction.
SmallPtrSet<MDNode *, 1> DistinctMDNodes;
DenseMap<Type*, ConstantAggregateZero*> CAZConstants;
typedef ConstantUniqueMap<ConstantArray> ArrayConstantsTy;
ArrayConstantsTy ArrayConstants;
typedef ConstantUniqueMap<ConstantStruct> StructConstantsTy;
StructConstantsTy StructConstants;
typedef ConstantUniqueMap<ConstantVector> VectorConstantsTy;
VectorConstantsTy VectorConstants;
DenseMap<PointerType*, ConstantPointerNull*> CPNConstants;
DenseMap<Type*, UndefValue*> UVConstants;
StringMap<ConstantDataSequential*> CDSConstants;
DenseMap<std::pair<const Function *, const BasicBlock *>, BlockAddress *>
BlockAddresses;
ConstantUniqueMap<ConstantExpr> ExprConstants;
ConstantUniqueMap<InlineAsm> InlineAsms;
ConstantInt *TheTrueVal;
ConstantInt *TheFalseVal;
// Basic type instances.
Type VoidTy, LabelTy, HalfTy, FloatTy, DoubleTy, MetadataTy;
Type X86_FP80Ty, FP128Ty, PPC_FP128Ty, X86_MMXTy;
IntegerType Int1Ty, Int8Ty, Int16Ty, Int32Ty, Int64Ty, Int128Ty;
/// TypeAllocator - All dynamically allocated types are allocated from this.
/// They live forever until the context is torn down.
BumpPtrAllocator TypeAllocator;
DenseMap<unsigned, IntegerType*> IntegerTypes;
typedef DenseSet<FunctionType *, FunctionTypeKeyInfo> FunctionTypeSet;
FunctionTypeSet FunctionTypes;
typedef DenseSet<StructType *, AnonStructTypeKeyInfo> StructTypeSet;
StructTypeSet AnonStructTypes;
StringMap<StructType*> NamedStructTypes;
unsigned NamedStructTypesUniqueID;
DenseMap<std::pair<Type *, uint64_t>, ArrayType*> ArrayTypes;
DenseMap<std::pair<Type *, unsigned>, VectorType*> VectorTypes;
DenseMap<Type*, PointerType*> PointerTypes; // Pointers in AddrSpace = 0
DenseMap<std::pair<Type*, unsigned>, PointerType*> ASPointerTypes;
/// ValueHandles - This map keeps track of all of the value handles that are
/// watching a Value*. The Value::HasValueHandle bit is used to know
/// whether or not a value has an entry in this map.
typedef DenseMap<Value*, ValueHandleBase*> ValueHandlesTy;
ValueHandlesTy ValueHandles;
/// CustomMDKindNames - Map to hold the metadata string to ID mapping.
StringMap<unsigned> CustomMDKindNames;
/// Collection of per-instruction metadata used in this context.
DenseMap<const Instruction *, MDAttachmentMap> InstructionMetadata;
/// Collection of per-function metadata used in this context.
DenseMap<const Function *, MDAttachmentMap> FunctionMetadata;
/// DiscriminatorTable - This table maps file:line locations to an
/// integer representing the next DWARF path discriminator to assign to
/// instructions in different blocks at the same location.
DenseMap<std::pair<const char *, unsigned>, unsigned> DiscriminatorTable;
/// \brief Mapping from a function to its prefix data, which is stored as the
/// operand of an unparented ReturnInst so that the prefix data has a Use.
typedef DenseMap<const Function *, ReturnInst *> PrefixDataMapTy;
PrefixDataMapTy PrefixDataMap;
/// \brief Mapping from a function to its prologue data, which is stored as
/// the operand of an unparented ReturnInst so that the prologue data has a
/// Use.
typedef DenseMap<const Function *, ReturnInst *> PrologueDataMapTy;
PrologueDataMapTy PrologueDataMap;
int getOrAddScopeRecordIdxEntry(MDNode *N, int ExistingIdx);
int getOrAddScopeInlinedAtIdxEntry(MDNode *Scope, MDNode *IA,int ExistingIdx);
LLVMContextImpl(LLVMContext &C);
~LLVMContextImpl();
/// Destroy the ConstantArrays if they are not used.
void dropTriviallyDeadConstantArrays();
};
}
#endif
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/Comdat.cpp | //===-- Comdat.cpp - Implement Metadata classes --------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the Comdat class.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/Comdat.h"
#include "llvm/ADT/StringMap.h"
using namespace llvm;
Comdat::Comdat(SelectionKind SK, StringMapEntry<Comdat> *Name)
: Name(Name), SK(SK) {}
Comdat::Comdat(Comdat &&C) : Name(C.Name), SK(C.SK) {}
Comdat::Comdat() : Name(nullptr), SK(Comdat::Any) {}
StringRef Comdat::getName() const { return Name->first(); }
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/MetadataImpl.h | //===- MetadataImpl.h - Helpers for implementing metadata -----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file has private helpers for implementing metadata types.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_IR_METADATAIMPL_H
#define LLVM_IR_METADATAIMPL_H
#include "llvm/ADT/DenseSet.h"
#include "llvm/IR/Metadata.h"
namespace llvm {
template <class T, class InfoT>
static T *getUniqued(DenseSet<T *, InfoT> &Store,
const typename InfoT::KeyTy &Key) {
auto I = Store.find_as(Key);
return I == Store.end() ? nullptr : *I;
}
template <class T, class StoreT>
T *MDNode::storeImpl(T *N, StorageType Storage, StoreT &Store) {
switch (Storage) {
case Uniqued:
Store.insert(N);
break;
case Distinct:
N->storeDistinctInContext();
break;
case Temporary:
break;
}
return N;
}
} // end namespace llvm
#endif
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/ConstantFold.h | //===-- ConstantFolding.h - Internal Constant Folding Interface -*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the (internal) constant folding interfaces for LLVM. These
// interfaces are used by the ConstantExpr::get* methods to automatically fold
// constants when possible.
//
// These operators may return a null object if they don't know how to perform
// the specified operation on the specified constant types.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_IR_CONSTANTFOLD_H
#define LLVM_LIB_IR_CONSTANTFOLD_H
#include "llvm/ADT/ArrayRef.h"
namespace llvm {
class Value;
class Constant;
class Type;
// Constant fold various types of instruction...
Constant *ConstantFoldCastInstruction(
unsigned opcode, ///< The opcode of the cast
Constant *V, ///< The source constant
Type *DestTy ///< The destination type
);
Constant *ConstantFoldSelectInstruction(Constant *Cond,
Constant *V1, Constant *V2);
Constant *ConstantFoldExtractElementInstruction(Constant *Val, Constant *Idx);
Constant *ConstantFoldInsertElementInstruction(Constant *Val, Constant *Elt,
Constant *Idx);
Constant *ConstantFoldShuffleVectorInstruction(Constant *V1, Constant *V2,
Constant *Mask);
Constant *ConstantFoldExtractValueInstruction(Constant *Agg,
ArrayRef<unsigned> Idxs);
Constant *ConstantFoldInsertValueInstruction(Constant *Agg, Constant *Val,
ArrayRef<unsigned> Idxs);
Constant *ConstantFoldBinaryInstruction(unsigned Opcode, Constant *V1,
Constant *V2);
Constant *ConstantFoldCompareInstruction(unsigned short predicate,
Constant *C1, Constant *C2);
Constant *ConstantFoldGetElementPtr(Constant *C, bool inBounds,
ArrayRef<Constant *> Idxs);
Constant *ConstantFoldGetElementPtr(Constant *C, bool inBounds,
ArrayRef<Value *> Idxs);
Constant *ConstantFoldGetElementPtr(Type *Ty, Constant *C, bool inBounds,
ArrayRef<Constant *> Idxs);
Constant *ConstantFoldGetElementPtr(Type *Ty, Constant *C, bool inBounds,
ArrayRef<Value *> Idxs);
} // End llvm namespace
#endif
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/SymbolTableListTraitsImpl.h | //===-- llvm/SymbolTableListTraitsImpl.h - Implementation ------*- C++ -*--===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the stickier parts of the SymbolTableListTraits class,
// and is explicitly instantiated where needed to avoid defining all this code
// in a widely used header.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_IR_SYMBOLTABLELISTTRAITSIMPL_H
#define LLVM_LIB_IR_SYMBOLTABLELISTTRAITSIMPL_H
#include "llvm/IR/SymbolTableListTraits.h"
#include "llvm/IR/ValueSymbolTable.h"
namespace llvm {
/// setSymTabObject - This is called when (f.e.) the parent of a basic block
/// changes. This requires us to remove all the instruction symtab entries from
/// the current function and reinsert them into the new function.
template<typename ValueSubClass, typename ItemParentClass>
template<typename TPtr>
void SymbolTableListTraits<ValueSubClass,ItemParentClass>
::setSymTabObject(TPtr *Dest, TPtr Src) {
// Get the old symtab and value list before doing the assignment.
ValueSymbolTable *OldST = TraitsClass::getSymTab(getListOwner());
// Do it.
*Dest = Src;
// Get the new SymTab object.
ValueSymbolTable *NewST = TraitsClass::getSymTab(getListOwner());
// If there is nothing to do, quick exit.
if (OldST == NewST) return;
// Move all the elements from the old symtab to the new one.
iplist<ValueSubClass> &ItemList = TraitsClass::getList(getListOwner());
if (ItemList.empty()) return;
if (OldST) {
// Remove all entries from the previous symtab.
for (typename iplist<ValueSubClass>::iterator I = ItemList.begin();
I != ItemList.end(); ++I)
if (I->hasName())
OldST->removeValueName(I->getValueName());
}
if (NewST) {
// Add all of the items to the new symtab.
for (typename iplist<ValueSubClass>::iterator I = ItemList.begin();
I != ItemList.end(); ++I)
if (I->hasName())
NewST->reinsertValue(I);
}
}
template<typename ValueSubClass, typename ItemParentClass>
void SymbolTableListTraits<ValueSubClass,ItemParentClass>
::addNodeToList(ValueSubClass *V) {
assert(!V->getParent() && "Value already in a container!!");
ItemParentClass *Owner = getListOwner();
V->setParent(Owner);
if (V->hasName())
if (ValueSymbolTable *ST = TraitsClass::getSymTab(Owner))
ST->reinsertValue(V);
}
template<typename ValueSubClass, typename ItemParentClass>
void SymbolTableListTraits<ValueSubClass,ItemParentClass>
::removeNodeFromList(ValueSubClass *V) {
V->setParent(nullptr);
if (V->hasName())
if (ValueSymbolTable *ST = TraitsClass::getSymTab(getListOwner()))
ST->removeValueName(V->getValueName());
}
template<typename ValueSubClass, typename ItemParentClass>
void SymbolTableListTraits<ValueSubClass,ItemParentClass>
::transferNodesFromList(ilist_traits<ValueSubClass> &L2,
ilist_iterator<ValueSubClass> first,
ilist_iterator<ValueSubClass> last) {
// We only have to do work here if transferring instructions between BBs
ItemParentClass *NewIP = getListOwner(), *OldIP = L2.getListOwner();
if (NewIP == OldIP) return; // No work to do at all...
// We only have to update symbol table entries if we are transferring the
// instructions to a different symtab object...
ValueSymbolTable *NewST = TraitsClass::getSymTab(NewIP);
ValueSymbolTable *OldST = TraitsClass::getSymTab(OldIP);
if (NewST != OldST) {
for (; first != last; ++first) {
ValueSubClass &V = *first;
bool HasName = V.hasName();
if (OldST && HasName)
OldST->removeValueName(V.getValueName());
V.setParent(NewIP);
if (NewST && HasName)
NewST->reinsertValue(&V);
}
} else {
// Just transferring between blocks in the same function, simply update the
// parent fields in the instructions...
for (; first != last; ++first)
first->setParent(NewIP);
}
}
} // End llvm namespace
#endif
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/DIBuilder.cpp | //===--- DIBuilder.cpp - Debug Information Builder ------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the DIBuilder.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/DIBuilder.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Dwarf.h"
using namespace llvm;
using namespace llvm::dwarf;
namespace {
class HeaderBuilder {
/// \brief Whether there are any fields yet.
///
/// Note that this is not equivalent to \c Chars.empty(), since \a concat()
/// may have been called already with an empty string.
bool IsEmpty;
SmallVector<char, 256> Chars;
public:
HeaderBuilder() : IsEmpty(true) {}
HeaderBuilder(const HeaderBuilder &X) : IsEmpty(X.IsEmpty), Chars(X.Chars) {}
HeaderBuilder(HeaderBuilder &&X)
: IsEmpty(X.IsEmpty), Chars(std::move(X.Chars)) {}
template <class Twineable> HeaderBuilder &concat(Twineable &&X) {
if (IsEmpty)
IsEmpty = false;
else
Chars.push_back(0);
Twine(X).toVector(Chars);
return *this;
}
MDString *get(LLVMContext &Context) const {
return MDString::get(Context, StringRef(Chars.begin(), Chars.size()));
}
static HeaderBuilder get(unsigned Tag) {
return HeaderBuilder().concat("0x" + Twine::utohexstr(Tag));
}
};
}
DIBuilder::DIBuilder(Module &m, bool AllowUnresolvedNodes)
: M(m), VMContext(M.getContext()), CUNode(nullptr),
DeclareFn(nullptr), ValueFn(nullptr),
AllowUnresolvedNodes(AllowUnresolvedNodes) {}
void DIBuilder::trackIfUnresolved(MDNode *N) {
if (!N)
return;
if (N->isResolved())
return;
assert(AllowUnresolvedNodes && "Cannot handle unresolved nodes");
UnresolvedNodes.emplace_back(N);
}
void DIBuilder::finalize() {
if (!CUNode) {
assert(!AllowUnresolvedNodes &&
"creating type nodes without a CU is not supported");
return;
}
CUNode->replaceEnumTypes(MDTuple::get(VMContext, AllEnumTypes));
SmallVector<Metadata *, 16> RetainValues;
// Declarations and definitions of the same type may be retained. Some
// clients RAUW these pairs, leaving duplicates in the retained types
// list. Use a set to remove the duplicates while we transform the
// TrackingVHs back into Values.
SmallPtrSet<Metadata *, 16> RetainSet;
for (unsigned I = 0, E = AllRetainTypes.size(); I < E; I++)
if (RetainSet.insert(AllRetainTypes[I]).second)
RetainValues.push_back(AllRetainTypes[I]);
if (!RetainValues.empty())
CUNode->replaceRetainedTypes(MDTuple::get(VMContext, RetainValues));
DISubprogramArray SPs = MDTuple::get(VMContext, AllSubprograms);
if (!AllSubprograms.empty())
CUNode->replaceSubprograms(SPs.get());
for (auto *SP : SPs) {
if (MDTuple *Temp = SP->getVariables().get()) {
const auto &PV = PreservedVariables.lookup(SP);
SmallVector<Metadata *, 4> Variables(PV.begin(), PV.end());
DINodeArray AV = getOrCreateArray(Variables);
TempMDTuple(Temp)->replaceAllUsesWith(AV.get());
}
}
if (!AllGVs.empty())
CUNode->replaceGlobalVariables(MDTuple::get(VMContext, AllGVs));
if (!AllImportedModules.empty())
CUNode->replaceImportedEntities(MDTuple::get(
VMContext, SmallVector<Metadata *, 16>(AllImportedModules.begin(),
AllImportedModules.end())));
// Now that all temp nodes have been replaced or deleted, resolve remaining
// cycles.
for (const auto &N : UnresolvedNodes)
if (N && !N->isResolved())
N->resolveCycles();
UnresolvedNodes.clear();
// Can't handle unresolved nodes anymore.
AllowUnresolvedNodes = false;
}
/// If N is compile unit return NULL otherwise return N.
static DIScope *getNonCompileUnitScope(DIScope *N) {
if (!N || isa<DICompileUnit>(N))
return nullptr;
return cast<DIScope>(N);
}
DICompileUnit *DIBuilder::createCompileUnit(
unsigned Lang, StringRef Filename, StringRef Directory, StringRef Producer,
bool isOptimized, StringRef Flags, unsigned RunTimeVer, StringRef SplitName,
DebugEmissionKind Kind, uint64_t DWOId, bool EmitDebugInfo) {
assert(((Lang <= dwarf::DW_LANG_Fortran08 && Lang >= dwarf::DW_LANG_C89) ||
(Lang <= dwarf::DW_LANG_hi_user && Lang >= dwarf::DW_LANG_lo_user)) &&
"Invalid Language tag");
assert(!Filename.empty() &&
"Unable to create compile unit without filename");
assert(!CUNode && "Can only make one compile unit per DIBuilder instance");
CUNode = DICompileUnit::getDistinct(
VMContext, Lang, DIFile::get(VMContext, Filename, Directory), Producer,
isOptimized, Flags, RunTimeVer, SplitName, Kind, nullptr,
nullptr, nullptr, nullptr, nullptr, DWOId);
// Create a named metadata so that it is easier to find cu in a module.
// Note that we only generate this when the caller wants to actually
// emit debug information. When we are only interested in tracking
// source line locations throughout the backend, we prevent codegen from
// emitting debug info in the final output by not generating llvm.dbg.cu.
if (EmitDebugInfo) {
NamedMDNode *NMD = M.getOrInsertNamedMetadata("llvm.dbg.cu");
NMD->addOperand(CUNode);
}
trackIfUnresolved(CUNode);
return CUNode;
}
static DIImportedEntity *
createImportedModule(LLVMContext &C, dwarf::Tag Tag, DIScope *Context,
Metadata *NS, unsigned Line, StringRef Name,
SmallVectorImpl<TrackingMDNodeRef> &AllImportedModules) {
auto *M = DIImportedEntity::get(C, Tag, Context, DINodeRef(NS), Line, Name);
AllImportedModules.emplace_back(M);
return M;
}
DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context,
DINamespace *NS,
unsigned Line) {
return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
Context, NS, Line, StringRef(), AllImportedModules);
}
DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context,
DIImportedEntity *NS,
unsigned Line) {
return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
Context, NS, Line, StringRef(), AllImportedModules);
}
DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context, DIModule *M,
unsigned Line) {
return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
Context, M, Line, StringRef(), AllImportedModules);
}
DIImportedEntity *DIBuilder::createImportedDeclaration(DIScope *Context,
DINode *Decl,
unsigned Line,
StringRef Name) {
// Make sure to use the unique identifier based metadata reference for
// types that have one.
return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_declaration,
Context, DINodeRef::get(Decl), Line, Name,
AllImportedModules);
}
DIFile *DIBuilder::createFile(StringRef Filename, StringRef Directory) {
return DIFile::get(VMContext, Filename, Directory);
}
DIEnumerator *DIBuilder::createEnumerator(StringRef Name, int64_t Val) {
assert(!Name.empty() && "Unable to create enumerator without name");
return DIEnumerator::get(VMContext, Val, Name);
}
DIBasicType *DIBuilder::createUnspecifiedType(StringRef Name) {
assert(!Name.empty() && "Unable to create type without name");
return DIBasicType::get(VMContext, dwarf::DW_TAG_unspecified_type, Name);
}
DIBasicType *DIBuilder::createNullPtrType() {
return createUnspecifiedType("decltype(nullptr)");
}
DIBasicType *DIBuilder::createBasicType(StringRef Name, uint64_t SizeInBits,
uint64_t AlignInBits,
unsigned Encoding) {
assert(!Name.empty() && "Unable to create type without name");
return DIBasicType::get(VMContext, dwarf::DW_TAG_base_type, Name, SizeInBits,
AlignInBits, Encoding);
}
DIDerivedType *DIBuilder::createQualifiedType(unsigned Tag, DIType *FromTy) {
return DIDerivedType::get(VMContext, Tag, "", nullptr, 0, nullptr,
DITypeRef::get(FromTy), 0, 0, 0, 0);
}
DIDerivedType *DIBuilder::createPointerType(DIType *PointeeTy,
uint64_t SizeInBits,
uint64_t AlignInBits,
StringRef Name) {
// FIXME: Why is there a name here?
return DIDerivedType::get(VMContext, dwarf::DW_TAG_pointer_type, Name,
nullptr, 0, nullptr, DITypeRef::get(PointeeTy),
SizeInBits, AlignInBits, 0, 0);
}
DIDerivedType *DIBuilder::createMemberPointerType(DIType *PointeeTy,
DIType *Base,
uint64_t SizeInBits,
uint64_t AlignInBits) {
return DIDerivedType::get(VMContext, dwarf::DW_TAG_ptr_to_member_type, "",
nullptr, 0, nullptr, DITypeRef::get(PointeeTy),
SizeInBits, AlignInBits, 0, 0,
DITypeRef::get(Base));
}
DIDerivedType *DIBuilder::createReferenceType(unsigned Tag, DIType *RTy) {
assert(RTy && "Unable to create reference type");
return DIDerivedType::get(VMContext, Tag, "", nullptr, 0, nullptr,
DITypeRef::get(RTy), 0, 0, 0, 0);
}
DIDerivedType *DIBuilder::createTypedef(DIType *Ty, StringRef Name,
DIFile *File, unsigned LineNo,
DIScope *Context) {
return DIDerivedType::get(VMContext, dwarf::DW_TAG_typedef, Name, File,
LineNo,
DIScopeRef::get(getNonCompileUnitScope(Context)),
DITypeRef::get(Ty), 0, 0, 0, 0);
}
DIDerivedType *DIBuilder::createFriend(DIType *Ty, DIType *FriendTy) {
assert(Ty && "Invalid type!");
assert(FriendTy && "Invalid friend type!");
return DIDerivedType::get(VMContext, dwarf::DW_TAG_friend, "", nullptr, 0,
DITypeRef::get(Ty), DITypeRef::get(FriendTy), 0, 0,
0, 0);
}
DIDerivedType *DIBuilder::createInheritance(DIType *Ty, DIType *BaseTy,
uint64_t BaseOffset,
unsigned Flags) {
assert(Ty && "Unable to create inheritance");
return DIDerivedType::get(VMContext, dwarf::DW_TAG_inheritance, "", nullptr,
0, DITypeRef::get(Ty), DITypeRef::get(BaseTy), 0, 0,
BaseOffset, Flags);
}
DIDerivedType *DIBuilder::createMemberType(DIScope *Scope, StringRef Name,
DIFile *File, unsigned LineNumber,
uint64_t SizeInBits,
uint64_t AlignInBits,
uint64_t OffsetInBits,
unsigned Flags, DIType *Ty) {
return DIDerivedType::get(
VMContext, dwarf::DW_TAG_member, Name, File, LineNumber,
DIScopeRef::get(getNonCompileUnitScope(Scope)), DITypeRef::get(Ty),
SizeInBits, AlignInBits, OffsetInBits, Flags);
}
static ConstantAsMetadata *getConstantOrNull(Constant *C) {
if (C)
return ConstantAsMetadata::get(C);
return nullptr;
}
DIDerivedType *DIBuilder::createStaticMemberType(DIScope *Scope, StringRef Name,
DIFile *File,
unsigned LineNumber,
DIType *Ty, unsigned Flags,
llvm::Constant *Val) {
Flags |= DINode::FlagStaticMember;
return DIDerivedType::get(
VMContext, dwarf::DW_TAG_member, Name, File, LineNumber,
DIScopeRef::get(getNonCompileUnitScope(Scope)), DITypeRef::get(Ty), 0, 0,
0, Flags, getConstantOrNull(Val));
}
DIDerivedType *DIBuilder::createObjCIVar(StringRef Name, DIFile *File,
unsigned LineNumber,
uint64_t SizeInBits,
uint64_t AlignInBits,
uint64_t OffsetInBits, unsigned Flags,
DIType *Ty, MDNode *PropertyNode) {
return DIDerivedType::get(
VMContext, dwarf::DW_TAG_member, Name, File, LineNumber,
DIScopeRef::get(getNonCompileUnitScope(File)), DITypeRef::get(Ty),
SizeInBits, AlignInBits, OffsetInBits, Flags, PropertyNode);
}
DIObjCProperty *
DIBuilder::createObjCProperty(StringRef Name, DIFile *File, unsigned LineNumber,
StringRef GetterName, StringRef SetterName,
unsigned PropertyAttributes, DIType *Ty) {
return DIObjCProperty::get(VMContext, Name, File, LineNumber, GetterName,
SetterName, PropertyAttributes,
DITypeRef::get(Ty));
}
DITemplateTypeParameter *
DIBuilder::createTemplateTypeParameter(DIScope *Context, StringRef Name,
DIType *Ty) {
assert((!Context || isa<DICompileUnit>(Context)) && "Expected compile unit");
return DITemplateTypeParameter::get(VMContext, Name, DITypeRef::get(Ty));
}
static DITemplateValueParameter *
createTemplateValueParameterHelper(LLVMContext &VMContext, unsigned Tag,
DIScope *Context, StringRef Name, DIType *Ty,
Metadata *MD) {
assert((!Context || isa<DICompileUnit>(Context)) && "Expected compile unit");
return DITemplateValueParameter::get(VMContext, Tag, Name, DITypeRef::get(Ty),
MD);
}
DITemplateValueParameter *
DIBuilder::createTemplateValueParameter(DIScope *Context, StringRef Name,
DIType *Ty, Constant *Val) {
return createTemplateValueParameterHelper(
VMContext, dwarf::DW_TAG_template_value_parameter, Context, Name, Ty,
getConstantOrNull(Val));
}
DITemplateValueParameter *
DIBuilder::createTemplateTemplateParameter(DIScope *Context, StringRef Name,
DIType *Ty, StringRef Val) {
return createTemplateValueParameterHelper(
VMContext, dwarf::DW_TAG_GNU_template_template_param, Context, Name, Ty,
MDString::get(VMContext, Val));
}
DITemplateValueParameter *
DIBuilder::createTemplateParameterPack(DIScope *Context, StringRef Name,
DIType *Ty, DINodeArray Val) {
return createTemplateValueParameterHelper(
VMContext, dwarf::DW_TAG_GNU_template_parameter_pack, Context, Name, Ty,
Val.get());
}
DICompositeType *DIBuilder::createClassType(
DIScope *Context, StringRef Name, DIFile *File, unsigned LineNumber,
uint64_t SizeInBits, uint64_t AlignInBits, uint64_t OffsetInBits,
unsigned Flags, DIType *DerivedFrom, DINodeArray Elements,
DIType *VTableHolder, MDNode *TemplateParams, StringRef UniqueIdentifier) {
assert((!Context || isa<DIScope>(Context)) &&
"createClassType should be called with a valid Context");
auto *R = DICompositeType::get(
VMContext, dwarf::DW_TAG_structure_type, Name, File, LineNumber,
DIScopeRef::get(getNonCompileUnitScope(Context)),
DITypeRef::get(DerivedFrom), SizeInBits, AlignInBits, OffsetInBits, Flags,
Elements, 0, DITypeRef::get(VTableHolder),
cast_or_null<MDTuple>(TemplateParams), UniqueIdentifier);
if (!UniqueIdentifier.empty())
retainType(R);
trackIfUnresolved(R);
return R;
}
DICompositeType *DIBuilder::createStructType(
DIScope *Context, StringRef Name, DIFile *File, unsigned LineNumber,
uint64_t SizeInBits, uint64_t AlignInBits, unsigned Flags,
DIType *DerivedFrom, DINodeArray Elements, unsigned RunTimeLang,
DIType *VTableHolder, StringRef UniqueIdentifier) {
auto *R = DICompositeType::get(
VMContext, dwarf::DW_TAG_structure_type, Name, File, LineNumber,
DIScopeRef::get(getNonCompileUnitScope(Context)),
DITypeRef::get(DerivedFrom), SizeInBits, AlignInBits, 0, Flags, Elements,
RunTimeLang, DITypeRef::get(VTableHolder), nullptr, UniqueIdentifier);
if (!UniqueIdentifier.empty())
retainType(R);
trackIfUnresolved(R);
return R;
}
DICompositeType *DIBuilder::createUnionType(
DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
uint64_t SizeInBits, uint64_t AlignInBits, unsigned Flags,
DINodeArray Elements, unsigned RunTimeLang, StringRef UniqueIdentifier) {
auto *R = DICompositeType::get(
VMContext, dwarf::DW_TAG_union_type, Name, File, LineNumber,
DIScopeRef::get(getNonCompileUnitScope(Scope)), nullptr, SizeInBits,
AlignInBits, 0, Flags, Elements, RunTimeLang, nullptr, nullptr,
UniqueIdentifier);
if (!UniqueIdentifier.empty())
retainType(R);
trackIfUnresolved(R);
return R;
}
DISubroutineType *DIBuilder::createSubroutineType(DIFile *File,
DITypeRefArray ParameterTypes,
unsigned Flags) {
return DISubroutineType::get(VMContext, Flags, ParameterTypes);
}
DICompositeType *DIBuilder::createEnumerationType(
DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
uint64_t SizeInBits, uint64_t AlignInBits, DINodeArray Elements,
DIType *UnderlyingType, StringRef UniqueIdentifier) {
auto *CTy = DICompositeType::get(
VMContext, dwarf::DW_TAG_enumeration_type, Name, File, LineNumber,
DIScopeRef::get(getNonCompileUnitScope(Scope)),
DITypeRef::get(UnderlyingType), SizeInBits, AlignInBits, 0, 0, Elements,
0, nullptr, nullptr, UniqueIdentifier);
AllEnumTypes.push_back(CTy);
if (!UniqueIdentifier.empty())
retainType(CTy);
trackIfUnresolved(CTy);
return CTy;
}
DICompositeType *DIBuilder::createArrayType(uint64_t Size, uint64_t AlignInBits,
DIType *Ty,
DINodeArray Subscripts) {
auto *R = DICompositeType::get(VMContext, dwarf::DW_TAG_array_type, "",
nullptr, 0, nullptr, DITypeRef::get(Ty), Size,
AlignInBits, 0, 0, Subscripts, 0, nullptr);
trackIfUnresolved(R);
return R;
}
DICompositeType *DIBuilder::createVectorType(uint64_t Size,
uint64_t AlignInBits, DIType *Ty,
DINodeArray Subscripts) {
auto *R =
DICompositeType::get(VMContext, dwarf::DW_TAG_array_type, "", nullptr, 0,
nullptr, DITypeRef::get(Ty), Size, AlignInBits, 0,
DINode::FlagVector, Subscripts, 0, nullptr);
trackIfUnresolved(R);
return R;
}
static DIType *createTypeWithFlags(LLVMContext &Context, DIType *Ty,
unsigned FlagsToSet) {
auto NewTy = Ty->clone();
NewTy->setFlags(NewTy->getFlags() | FlagsToSet);
return MDNode::replaceWithUniqued(std::move(NewTy));
}
DIType *DIBuilder::createArtificialType(DIType *Ty) {
// FIXME: Restrict this to the nodes where it's valid.
if (Ty->isArtificial())
return Ty;
return createTypeWithFlags(VMContext, Ty, DINode::FlagArtificial);
}
DIType *DIBuilder::createObjectPointerType(DIType *Ty) {
// FIXME: Restrict this to the nodes where it's valid.
if (Ty->isObjectPointer())
return Ty;
unsigned Flags = DINode::FlagObjectPointer | DINode::FlagArtificial;
return createTypeWithFlags(VMContext, Ty, Flags);
}
void DIBuilder::retainType(DIType *T) {
assert(T && "Expected non-null type");
AllRetainTypes.emplace_back(T);
}
DIBasicType *DIBuilder::createUnspecifiedParameter() { return nullptr; }
DICompositeType *
DIBuilder::createForwardDecl(unsigned Tag, StringRef Name, DIScope *Scope,
DIFile *F, unsigned Line, unsigned RuntimeLang,
uint64_t SizeInBits, uint64_t AlignInBits,
StringRef UniqueIdentifier) {
// FIXME: Define in terms of createReplaceableForwardDecl() by calling
// replaceWithUniqued().
auto *RetTy = DICompositeType::get(
VMContext, Tag, Name, F, Line,
DIScopeRef::get(getNonCompileUnitScope(Scope)), nullptr, SizeInBits,
AlignInBits, 0, DINode::FlagFwdDecl, nullptr, RuntimeLang, nullptr,
nullptr, UniqueIdentifier);
if (!UniqueIdentifier.empty())
retainType(RetTy);
trackIfUnresolved(RetTy);
return RetTy;
}
DICompositeType *DIBuilder::createReplaceableCompositeType(
unsigned Tag, StringRef Name, DIScope *Scope, DIFile *F, unsigned Line,
unsigned RuntimeLang, uint64_t SizeInBits, uint64_t AlignInBits,
unsigned Flags, StringRef UniqueIdentifier) {
auto *RetTy = DICompositeType::getTemporary(
VMContext, Tag, Name, F, Line,
DIScopeRef::get(getNonCompileUnitScope(Scope)), nullptr,
SizeInBits, AlignInBits, 0, Flags, nullptr, RuntimeLang,
nullptr, nullptr, UniqueIdentifier)
.release();
if (!UniqueIdentifier.empty())
retainType(RetTy);
trackIfUnresolved(RetTy);
return RetTy;
}
DINodeArray DIBuilder::getOrCreateArray(ArrayRef<Metadata *> Elements) {
return MDTuple::get(VMContext, Elements);
}
DITypeRefArray DIBuilder::getOrCreateTypeArray(ArrayRef<Metadata *> Elements) {
SmallVector<llvm::Metadata *, 16> Elts;
for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
if (Elements[i] && isa<MDNode>(Elements[i]))
Elts.push_back(DITypeRef::get(cast<DIType>(Elements[i])));
else
Elts.push_back(Elements[i]);
}
return DITypeRefArray(MDNode::get(VMContext, Elts));
}
DISubrange *DIBuilder::getOrCreateSubrange(int64_t Lo, int64_t Count) {
return DISubrange::get(VMContext, Count, Lo);
}
static void checkGlobalVariableScope(DIScope *Context) {
#ifndef NDEBUG
if (auto *CT =
dyn_cast_or_null<DICompositeType>(getNonCompileUnitScope(Context)))
assert(CT->getIdentifier().empty() &&
"Context of a global variable should not be a type with identifier");
#endif
}
DIGlobalVariable *DIBuilder::createGlobalVariable(
DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *F,
unsigned LineNumber, DIType *Ty, bool isLocalToUnit, Constant *Val,
MDNode *Decl) {
checkGlobalVariableScope(Context);
auto *N = DIGlobalVariable::get(VMContext, cast_or_null<DIScope>(Context),
Name, LinkageName, F, LineNumber,
DITypeRef::get(Ty), isLocalToUnit, true, Val,
cast_or_null<DIDerivedType>(Decl));
AllGVs.push_back(N);
return N;
}
DIGlobalVariable *DIBuilder::createTempGlobalVariableFwdDecl(
DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *F,
unsigned LineNumber, DIType *Ty, bool isLocalToUnit, Constant *Val,
MDNode *Decl) {
checkGlobalVariableScope(Context);
return DIGlobalVariable::getTemporary(
VMContext, cast_or_null<DIScope>(Context), Name, LinkageName, F,
LineNumber, DITypeRef::get(Ty), isLocalToUnit, false, Val,
cast_or_null<DIDerivedType>(Decl))
.release();
}
DILocalVariable *DIBuilder::createLocalVariable(
unsigned Tag, DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNo,
DIType *Ty, bool AlwaysPreserve, unsigned Flags, unsigned ArgNo) {
// FIXME: Why getNonCompileUnitScope()?
// FIXME: Why is "!Context" okay here?
// FIXME: Why doesn't this check for a subprogram or lexical block (AFAICT
// the only valid scopes)?
DIScope *Context = getNonCompileUnitScope(Scope);
auto *Node = DILocalVariable::get(
VMContext, Tag, cast_or_null<DILocalScope>(Context), Name, File, LineNo,
DITypeRef::get(Ty), ArgNo, Flags);
if (AlwaysPreserve) {
// The optimizer may remove local variables. If there is an interest
// to preserve variable info in such situation then stash it in a
// named mdnode.
DISubprogram *Fn = getDISubprogram(Scope);
assert(Fn && "Missing subprogram for local variable");
PreservedVariables[Fn].emplace_back(Node);
}
return Node;
}
DIExpression *DIBuilder::createExpression(ArrayRef<uint64_t> Addr) {
return DIExpression::get(VMContext, Addr);
}
DIExpression *DIBuilder::createExpression(ArrayRef<int64_t> Signed) {
// TODO: Remove the callers of this signed version and delete.
SmallVector<uint64_t, 8> Addr(Signed.begin(), Signed.end());
return createExpression(Addr);
}
// HLSL Begin Change: Match -InBits suffixes from header
DIExpression *DIBuilder::createBitPieceExpression(unsigned OffsetInBits,
unsigned SizeInBits) {
uint64_t Addr[] = {dwarf::DW_OP_bit_piece, OffsetInBits, SizeInBits};
// HLSL End Change
return DIExpression::get(VMContext, Addr);
}
DISubprogram *DIBuilder::createFunction(DIScopeRef Context, StringRef Name,
StringRef LinkageName, DIFile *File,
unsigned LineNo, DISubroutineType *Ty,
bool isLocalToUnit, bool isDefinition,
unsigned ScopeLine, unsigned Flags,
bool isOptimized, Function *Fn,
MDNode *TParams, MDNode *Decl) {
// dragonegg does not generate identifier for types, so using an empty map
// to resolve the context should be fine.
DITypeIdentifierMap EmptyMap;
return createFunction(Context.resolve(EmptyMap), Name, LinkageName, File,
LineNo, Ty, isLocalToUnit, isDefinition, ScopeLine,
Flags, isOptimized, Fn, TParams, Decl);
}
DISubprogram *DIBuilder::createFunction(DIScope *Context, StringRef Name,
StringRef LinkageName, DIFile *File,
unsigned LineNo, DISubroutineType *Ty,
bool isLocalToUnit, bool isDefinition,
unsigned ScopeLine, unsigned Flags,
bool isOptimized, Function *Fn,
MDNode *TParams, MDNode *Decl) {
assert(Ty->getTag() == dwarf::DW_TAG_subroutine_type &&
"function types should be subroutines");
auto *Node = DISubprogram::get(
VMContext, DIScopeRef::get(getNonCompileUnitScope(Context)), Name,
LinkageName, File, LineNo, Ty, isLocalToUnit, isDefinition, ScopeLine,
nullptr, 0, 0, Flags, isOptimized, Fn, cast_or_null<MDTuple>(TParams),
cast_or_null<DISubprogram>(Decl),
nullptr); // HLSL Change - this leaked, better nullptr than empty anyway - MDTuple::getTemporary(VMContext, None).release());
if (isDefinition)
AllSubprograms.push_back(Node);
trackIfUnresolved(Node);
return Node;
}
DISubprogram *DIBuilder::createTempFunctionFwdDecl(
DIScope *Context, StringRef Name, StringRef LinkageName, DIFile *File,
unsigned LineNo, DISubroutineType *Ty, bool isLocalToUnit,
bool isDefinition, unsigned ScopeLine, unsigned Flags, bool isOptimized,
Function *Fn, MDNode *TParams, MDNode *Decl) {
return DISubprogram::getTemporary(
VMContext, DIScopeRef::get(getNonCompileUnitScope(Context)), Name,
LinkageName, File, LineNo, Ty, isLocalToUnit, isDefinition,
ScopeLine, nullptr, 0, 0, Flags, isOptimized, Fn,
cast_or_null<MDTuple>(TParams), cast_or_null<DISubprogram>(Decl),
nullptr)
.release();
}
DISubprogram *
DIBuilder::createMethod(DIScope *Context, StringRef Name, StringRef LinkageName,
DIFile *F, unsigned LineNo, DISubroutineType *Ty,
bool isLocalToUnit, bool isDefinition, unsigned VK,
unsigned VIndex, DIType *VTableHolder, unsigned Flags,
bool isOptimized, Function *Fn, MDNode *TParam) {
assert(Ty->getTag() == dwarf::DW_TAG_subroutine_type &&
"function types should be subroutines");
assert(getNonCompileUnitScope(Context) &&
"Methods should have both a Context and a context that isn't "
"the compile unit.");
// FIXME: Do we want to use different scope/lines?
auto *SP = DISubprogram::get(
VMContext, DIScopeRef::get(cast<DIScope>(Context)), Name, LinkageName, F,
LineNo, Ty, isLocalToUnit, isDefinition, LineNo,
DITypeRef::get(VTableHolder), VK, VIndex, Flags, isOptimized, Fn,
cast_or_null<MDTuple>(TParam), nullptr, nullptr);
if (isDefinition)
AllSubprograms.push_back(SP);
trackIfUnresolved(SP);
return SP;
}
DINamespace *DIBuilder::createNameSpace(DIScope *Scope, StringRef Name,
DIFile *File, unsigned LineNo) {
return DINamespace::get(VMContext, getNonCompileUnitScope(Scope), File, Name,
LineNo);
}
DIModule *DIBuilder::createModule(DIScope *Scope, StringRef Name,
StringRef ConfigurationMacros,
StringRef IncludePath,
StringRef ISysRoot) {
return DIModule::get(VMContext, getNonCompileUnitScope(Scope), Name,
ConfigurationMacros, IncludePath, ISysRoot);
}
DILexicalBlockFile *DIBuilder::createLexicalBlockFile(DIScope *Scope,
DIFile *File,
unsigned Discriminator) {
return DILexicalBlockFile::get(VMContext, Scope, File, Discriminator);
}
DILexicalBlock *DIBuilder::createLexicalBlock(DIScope *Scope, DIFile *File,
unsigned Line, unsigned Col) {
// Make these distinct, to avoid merging two lexical blocks on the same
// file/line/column.
return DILexicalBlock::getDistinct(VMContext, getNonCompileUnitScope(Scope),
File, Line, Col);
}
static Value *getDbgIntrinsicValueImpl(LLVMContext &VMContext, Value *V) {
assert(V && "no value passed to dbg intrinsic");
return MetadataAsValue::get(VMContext, ValueAsMetadata::get(V));
}
static Instruction *withDebugLoc(Instruction *I, const DILocation *DL) {
I->setDebugLoc(const_cast<DILocation *>(DL));
return I;
}
Instruction *DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
DIExpression *Expr, const DILocation *DL,
Instruction *InsertBefore) {
assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.declare");
assert(DL && "Expected debug loc");
assert(DL->getScope()->getSubprogram() ==
VarInfo->getScope()->getSubprogram() &&
"Expected matching subprograms");
if (!DeclareFn)
DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
trackIfUnresolved(VarInfo);
trackIfUnresolved(Expr);
Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, Storage),
MetadataAsValue::get(VMContext, VarInfo),
MetadataAsValue::get(VMContext, Expr)};
return withDebugLoc(CallInst::Create(DeclareFn, Args, "", InsertBefore), DL);
}
Instruction *DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
DIExpression *Expr, const DILocation *DL,
BasicBlock *InsertAtEnd) {
assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.declare");
assert(DL && "Expected debug loc");
assert(DL->getScope()->getSubprogram() ==
VarInfo->getScope()->getSubprogram() &&
"Expected matching subprograms");
if (!DeclareFn)
DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
trackIfUnresolved(VarInfo);
trackIfUnresolved(Expr);
Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, Storage),
MetadataAsValue::get(VMContext, VarInfo),
MetadataAsValue::get(VMContext, Expr)};
// If this block already has a terminator then insert this intrinsic
// before the terminator.
if (TerminatorInst *T = InsertAtEnd->getTerminator())
return withDebugLoc(CallInst::Create(DeclareFn, Args, "", T), DL);
return withDebugLoc(CallInst::Create(DeclareFn, Args, "", InsertAtEnd), DL);
}
Instruction *DIBuilder::insertDbgValueIntrinsic(Value *V, uint64_t Offset,
DILocalVariable *VarInfo,
DIExpression *Expr,
const DILocation *DL,
Instruction *InsertBefore) {
assert(V && "no value passed to dbg.value");
assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.value");
assert(DL && "Expected debug loc");
assert(DL->getScope()->getSubprogram() ==
VarInfo->getScope()->getSubprogram() &&
"Expected matching subprograms");
if (!ValueFn)
ValueFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_value);
trackIfUnresolved(VarInfo);
trackIfUnresolved(Expr);
Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, V),
ConstantInt::get(Type::getInt64Ty(VMContext), Offset),
MetadataAsValue::get(VMContext, VarInfo),
MetadataAsValue::get(VMContext, Expr)};
return withDebugLoc(CallInst::Create(ValueFn, Args, "", InsertBefore), DL);
}
Instruction *DIBuilder::insertDbgValueIntrinsic(Value *V, uint64_t Offset,
DILocalVariable *VarInfo,
DIExpression *Expr,
const DILocation *DL,
BasicBlock *InsertAtEnd) {
assert(V && "no value passed to dbg.value");
assert(VarInfo && "empty or invalid DILocalVariable* passed to dbg.value");
assert(DL && "Expected debug loc");
assert(DL->getScope()->getSubprogram() ==
VarInfo->getScope()->getSubprogram() &&
"Expected matching subprograms");
if (!ValueFn)
ValueFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_value);
trackIfUnresolved(VarInfo);
trackIfUnresolved(Expr);
Value *Args[] = {getDbgIntrinsicValueImpl(VMContext, V),
ConstantInt::get(Type::getInt64Ty(VMContext), Offset),
MetadataAsValue::get(VMContext, VarInfo),
MetadataAsValue::get(VMContext, Expr)};
return withDebugLoc(CallInst::Create(ValueFn, Args, "", InsertAtEnd), DL);
}
void DIBuilder::replaceVTableHolder(DICompositeType *&T,
DICompositeType *VTableHolder) {
{
TypedTrackingMDRef<DICompositeType> N(T);
N->replaceVTableHolder(DITypeRef::get(VTableHolder));
T = N.get();
}
// If this didn't create a self-reference, just return.
if (T != VTableHolder)
return;
// Look for unresolved operands. T will drop RAUW support, orphaning any
// cycles underneath it.
if (T->isResolved())
for (const MDOperand &O : T->operands())
if (auto *N = dyn_cast_or_null<MDNode>(O))
trackIfUnresolved(N);
}
void DIBuilder::replaceArrays(DICompositeType *&T, DINodeArray Elements,
DINodeArray TParams) {
{
TypedTrackingMDRef<DICompositeType> N(T);
if (Elements)
N->replaceElements(Elements);
if (TParams)
N->replaceTemplateParams(DITemplateParameterArray(TParams));
T = N.get();
}
// If T isn't resolved, there's no problem.
if (!T->isResolved())
return;
// If T is resolved, it may be due to a self-reference cycle. Track the
// arrays explicitly if they're unresolved, or else the cycles will be
// orphaned.
if (Elements)
trackIfUnresolved(Elements.get());
if (TParams)
trackIfUnresolved(TParams.get());
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/MetadataTracking.cpp | //===- MetadataTracking.cpp - Implement metadata tracking -----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements Metadata tracking.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/MetadataTracking.h"
#include "llvm/IR/Metadata.h"
using namespace llvm;
ReplaceableMetadataImpl *ReplaceableMetadataImpl::get(Metadata &MD) {
if (auto *N = dyn_cast<MDNode>(&MD))
return N->Context.getReplaceableUses();
return dyn_cast<ValueAsMetadata>(&MD);
}
bool MetadataTracking::track(void *Ref, Metadata &MD, OwnerTy Owner) {
assert(Ref && "Expected live reference");
assert((Owner || *static_cast<Metadata **>(Ref) == &MD) &&
"Reference without owner must be direct");
if (auto *R = ReplaceableMetadataImpl::get(MD)) {
R->addRef(Ref, Owner);
return true;
}
return false;
}
void MetadataTracking::untrack(void *Ref, Metadata &MD) {
assert(Ref && "Expected live reference");
if (auto *R = ReplaceableMetadataImpl::get(MD))
R->dropRef(Ref);
}
bool MetadataTracking::retrack(void *Ref, Metadata &MD, void *New) {
assert(Ref && "Expected live reference");
assert(New && "Expected live reference");
assert(Ref != New && "Expected change");
if (auto *R = ReplaceableMetadataImpl::get(MD)) {
R->moveRef(Ref, New, MD);
return true;
}
return false;
}
bool MetadataTracking::isReplaceable(const Metadata &MD) {
return ReplaceableMetadataImpl::get(const_cast<Metadata &>(MD));
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/Instructions.cpp | //===-- Instructions.cpp - Implement the LLVM instructions ----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements all of the non-inline methods for the LLVM instruction
// classes.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/Instructions.h"
#include "LLVMContextImpl.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/ConstantRange.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Operator.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MathExtras.h"
using namespace llvm;
//===----------------------------------------------------------------------===//
// CallSite Class
//===----------------------------------------------------------------------===//
User::op_iterator CallSite::getCallee() const {
Instruction *II(getInstruction());
return isCall()
? cast<CallInst>(II)->op_end() - 1 // Skip Callee
: cast<InvokeInst>(II)->op_end() - 3; // Skip BB, BB, Callee
}
//===----------------------------------------------------------------------===//
// TerminatorInst Class
//===----------------------------------------------------------------------===//
// Out of line virtual method, so the vtable, etc has a home.
TerminatorInst::~TerminatorInst() {
}
//===----------------------------------------------------------------------===//
// UnaryInstruction Class
//===----------------------------------------------------------------------===//
// Out of line virtual method, so the vtable, etc has a home.
UnaryInstruction::~UnaryInstruction() {
}
//===----------------------------------------------------------------------===//
// SelectInst Class
//===----------------------------------------------------------------------===//
/// areInvalidOperands - Return a string if the specified operands are invalid
/// for a select operation, otherwise return null.
const char *SelectInst::areInvalidOperands(Value *Op0, Value *Op1, Value *Op2) {
if (Op1->getType() != Op2->getType())
return "both values to select must have same type";
if (VectorType *VT = dyn_cast<VectorType>(Op0->getType())) {
// Vector select.
if (VT->getElementType() != Type::getInt1Ty(Op0->getContext()))
return "vector select condition element type must be i1";
VectorType *ET = dyn_cast<VectorType>(Op1->getType());
if (!ET)
return "selected values for vector select must be vectors";
if (ET->getNumElements() != VT->getNumElements())
return "vector select requires selected vectors to have "
"the same vector length as select condition";
} else if (Op0->getType() != Type::getInt1Ty(Op0->getContext())) {
return "select condition must be i1 or <n x i1>";
}
return nullptr;
}
//===----------------------------------------------------------------------===//
// PHINode Class
//===----------------------------------------------------------------------===//
PHINode::PHINode(const PHINode &PN)
: Instruction(PN.getType(), Instruction::PHI, nullptr, PN.getNumOperands()),
ReservedSpace(PN.getNumOperands()) {
allocHungoffUses(PN.getNumOperands());
std::copy(PN.op_begin(), PN.op_end(), op_begin());
std::copy(PN.block_begin(), PN.block_end(), block_begin());
SubclassOptionalData = PN.SubclassOptionalData;
}
// removeIncomingValue - Remove an incoming value. This is useful if a
// predecessor basic block is deleted.
Value *PHINode::removeIncomingValue(unsigned Idx, bool DeletePHIIfEmpty) {
Value *Removed = getIncomingValue(Idx);
// Move everything after this operand down.
//
// FIXME: we could just swap with the end of the list, then erase. However,
// clients might not expect this to happen. The code as it is thrashes the
// use/def lists, which is kinda lame.
std::copy(op_begin() + Idx + 1, op_end(), op_begin() + Idx);
std::copy(block_begin() + Idx + 1, block_end(), block_begin() + Idx);
// Nuke the last value.
Op<-1>().set(nullptr);
setNumHungOffUseOperands(getNumOperands() - 1);
// If the PHI node is dead, because it has zero entries, nuke it now.
if (getNumOperands() == 0 && DeletePHIIfEmpty) {
// If anyone is using this PHI, make them use a dummy value instead...
replaceAllUsesWith(UndefValue::get(getType()));
eraseFromParent();
}
return Removed;
}
/// growOperands - grow operands - This grows the operand list in response
/// to a push_back style of operation. This grows the number of ops by 1.5
/// times.
///
void PHINode::growOperands() {
unsigned e = getNumOperands();
unsigned NumOps = e + e / 2;
if (NumOps < 2) NumOps = 2; // 2 op PHI nodes are VERY common.
ReservedSpace = NumOps;
growHungoffUses(ReservedSpace, /* IsPhi */ true);
}
/// hasConstantValue - If the specified PHI node always merges together the same
/// value, return the value, otherwise return null.
Value *PHINode::hasConstantValue() const {
// Exploit the fact that phi nodes always have at least one entry.
Value *ConstantValue = getIncomingValue(0);
for (unsigned i = 1, e = getNumIncomingValues(); i != e; ++i)
if (getIncomingValue(i) != ConstantValue && getIncomingValue(i) != this) {
if (ConstantValue != this)
return nullptr; // Incoming values not all the same.
// The case where the first value is this PHI.
ConstantValue = getIncomingValue(i);
}
if (ConstantValue == this)
return UndefValue::get(getType());
return ConstantValue;
}
//===----------------------------------------------------------------------===//
// LandingPadInst Implementation
//===----------------------------------------------------------------------===//
LandingPadInst::LandingPadInst(Type *RetTy, unsigned NumReservedValues,
const Twine &NameStr, Instruction *InsertBefore)
: Instruction(RetTy, Instruction::LandingPad, nullptr, 0, InsertBefore) {
init(NumReservedValues, NameStr);
}
LandingPadInst::LandingPadInst(Type *RetTy, unsigned NumReservedValues,
const Twine &NameStr, BasicBlock *InsertAtEnd)
: Instruction(RetTy, Instruction::LandingPad, nullptr, 0, InsertAtEnd) {
init(NumReservedValues, NameStr);
}
LandingPadInst::LandingPadInst(const LandingPadInst &LP)
: Instruction(LP.getType(), Instruction::LandingPad, nullptr,
LP.getNumOperands()),
ReservedSpace(LP.getNumOperands()) {
allocHungoffUses(LP.getNumOperands());
Use *OL = getOperandList();
const Use *InOL = LP.getOperandList();
for (unsigned I = 0, E = ReservedSpace; I != E; ++I)
OL[I] = InOL[I];
setCleanup(LP.isCleanup());
}
LandingPadInst *LandingPadInst::Create(Type *RetTy, unsigned NumReservedClauses,
const Twine &NameStr,
Instruction *InsertBefore) {
return new LandingPadInst(RetTy, NumReservedClauses, NameStr, InsertBefore);
}
LandingPadInst *LandingPadInst::Create(Type *RetTy, unsigned NumReservedClauses,
const Twine &NameStr,
BasicBlock *InsertAtEnd) {
return new LandingPadInst(RetTy, NumReservedClauses, NameStr, InsertAtEnd);
}
void LandingPadInst::init(unsigned NumReservedValues, const Twine &NameStr) {
ReservedSpace = NumReservedValues;
setNumHungOffUseOperands(0);
allocHungoffUses(ReservedSpace);
setName(NameStr);
setCleanup(false);
}
/// growOperands - grow operands - This grows the operand list in response to a
/// push_back style of operation. This grows the number of ops by 2 times.
void LandingPadInst::growOperands(unsigned Size) {
unsigned e = getNumOperands();
if (ReservedSpace >= e + Size) return;
ReservedSpace = (std::max(e, 1U) + Size / 2) * 2;
growHungoffUses(ReservedSpace);
}
void LandingPadInst::addClause(Constant *Val) {
unsigned OpNo = getNumOperands();
growOperands(1);
assert(OpNo < ReservedSpace && "Growing didn't work!");
setNumHungOffUseOperands(getNumOperands() + 1);
getOperandList()[OpNo] = Val;
}
//===----------------------------------------------------------------------===//
// CallInst Implementation
//===----------------------------------------------------------------------===//
CallInst::~CallInst() {
}
void CallInst::init(FunctionType *FTy, Value *Func, ArrayRef<Value *> Args,
const Twine &NameStr) {
this->FTy = FTy;
assert(getNumOperands() == Args.size() + 1 && "NumOperands not set up?");
Op<-1>() = Func;
#ifndef NDEBUG
assert((Args.size() == FTy->getNumParams() ||
(FTy->isVarArg() && Args.size() > FTy->getNumParams())) &&
"Calling a function with bad signature!");
for (unsigned i = 0; i != Args.size(); ++i)
assert((i >= FTy->getNumParams() ||
FTy->getParamType(i) == Args[i]->getType()) &&
"Calling a function with a bad signature!");
#endif
std::copy(Args.begin(), Args.end(), op_begin());
setName(NameStr);
}
void CallInst::init(Value *Func, const Twine &NameStr) {
FTy =
cast<FunctionType>(cast<PointerType>(Func->getType())->getElementType());
assert(getNumOperands() == 1 && "NumOperands not set up?");
Op<-1>() = Func;
assert(FTy->getNumParams() == 0 && "Calling a function with bad signature");
setName(NameStr);
}
CallInst::CallInst(Value *Func, const Twine &Name,
Instruction *InsertBefore)
: Instruction(cast<FunctionType>(cast<PointerType>(Func->getType())
->getElementType())->getReturnType(),
Instruction::Call,
OperandTraits<CallInst>::op_end(this) - 1,
1, InsertBefore) {
init(Func, Name);
}
CallInst::CallInst(Value *Func, const Twine &Name,
BasicBlock *InsertAtEnd)
: Instruction(cast<FunctionType>(cast<PointerType>(Func->getType())
->getElementType())->getReturnType(),
Instruction::Call,
OperandTraits<CallInst>::op_end(this) - 1,
1, InsertAtEnd) {
init(Func, Name);
}
CallInst::CallInst(const CallInst &CI)
: Instruction(CI.getType(), Instruction::Call,
OperandTraits<CallInst>::op_end(this) - CI.getNumOperands(),
CI.getNumOperands()),
AttributeList(CI.AttributeList), FTy(CI.FTy) {
setTailCallKind(CI.getTailCallKind());
setCallingConv(CI.getCallingConv());
std::copy(CI.op_begin(), CI.op_end(), op_begin());
SubclassOptionalData = CI.SubclassOptionalData;
}
void CallInst::addAttribute(unsigned i, Attribute::AttrKind attr) {
AttributeSet PAL = getAttributes();
PAL = PAL.addAttribute(getContext(), i, attr);
setAttributes(PAL);
}
void CallInst::addAttribute(unsigned i, StringRef Kind, StringRef Value) {
AttributeSet PAL = getAttributes();
PAL = PAL.addAttribute(getContext(), i, Kind, Value);
setAttributes(PAL);
}
void CallInst::removeAttribute(unsigned i, Attribute attr) {
AttributeSet PAL = getAttributes();
AttrBuilder B(attr);
LLVMContext &Context = getContext();
PAL = PAL.removeAttributes(Context, i,
AttributeSet::get(Context, i, B));
setAttributes(PAL);
}
void CallInst::addDereferenceableAttr(unsigned i, uint64_t Bytes) {
AttributeSet PAL = getAttributes();
PAL = PAL.addDereferenceableAttr(getContext(), i, Bytes);
setAttributes(PAL);
}
void CallInst::addDereferenceableOrNullAttr(unsigned i, uint64_t Bytes) {
AttributeSet PAL = getAttributes();
PAL = PAL.addDereferenceableOrNullAttr(getContext(), i, Bytes);
setAttributes(PAL);
}
bool CallInst::paramHasAttr(unsigned i, Attribute::AttrKind A) const {
if (AttributeList.hasAttribute(i, A))
return true;
if (const Function *F = getCalledFunction())
return F->getAttributes().hasAttribute(i, A);
return false;
}
/// IsConstantOne - Return true only if val is constant int 1
static bool IsConstantOne(Value *val) {
assert(val && "IsConstantOne does not work with nullptr val");
const ConstantInt *CVal = dyn_cast<ConstantInt>(val);
return CVal && CVal->isOne();
}
static Instruction *createMalloc(Instruction *InsertBefore,
BasicBlock *InsertAtEnd, Type *IntPtrTy,
Type *AllocTy, Value *AllocSize,
Value *ArraySize, Function *MallocF,
const Twine &Name) {
assert(((!InsertBefore && InsertAtEnd) || (InsertBefore && !InsertAtEnd)) &&
"createMalloc needs either InsertBefore or InsertAtEnd");
// malloc(type) becomes:
// bitcast (i8* malloc(typeSize)) to type*
// malloc(type, arraySize) becomes:
// bitcast (i8 *malloc(typeSize*arraySize)) to type*
if (!ArraySize)
ArraySize = ConstantInt::get(IntPtrTy, 1);
else if (ArraySize->getType() != IntPtrTy) {
if (InsertBefore)
ArraySize = CastInst::CreateIntegerCast(ArraySize, IntPtrTy, false,
"", InsertBefore);
else
ArraySize = CastInst::CreateIntegerCast(ArraySize, IntPtrTy, false,
"", InsertAtEnd);
}
if (!IsConstantOne(ArraySize)) {
if (IsConstantOne(AllocSize)) {
AllocSize = ArraySize; // Operand * 1 = Operand
} else if (Constant *CO = dyn_cast<Constant>(ArraySize)) {
Constant *Scale = ConstantExpr::getIntegerCast(CO, IntPtrTy,
false /*ZExt*/);
// Malloc arg is constant product of type size and array size
AllocSize = ConstantExpr::getMul(Scale, cast<Constant>(AllocSize));
} else {
// Multiply type size by the array size...
if (InsertBefore)
AllocSize = BinaryOperator::CreateMul(ArraySize, AllocSize,
"mallocsize", InsertBefore);
else
AllocSize = BinaryOperator::CreateMul(ArraySize, AllocSize,
"mallocsize", InsertAtEnd);
}
}
assert(AllocSize->getType() == IntPtrTy && "malloc arg is wrong size");
// Create the call to Malloc.
BasicBlock* BB = InsertBefore ? InsertBefore->getParent() : InsertAtEnd;
Module* M = BB->getParent()->getParent();
Type *BPTy = Type::getInt8PtrTy(BB->getContext());
Value *MallocFunc = MallocF;
if (!MallocFunc)
// prototype malloc as "void *malloc(size_t)"
MallocFunc = M->getOrInsertFunction("malloc", BPTy, IntPtrTy, nullptr);
PointerType *AllocPtrType = PointerType::getUnqual(AllocTy);
CallInst *MCall = nullptr;
Instruction *Result = nullptr;
if (InsertBefore) {
MCall = CallInst::Create(MallocFunc, AllocSize, "malloccall", InsertBefore);
Result = MCall;
if (Result->getType() != AllocPtrType)
// Create a cast instruction to convert to the right type...
Result = new BitCastInst(MCall, AllocPtrType, Name, InsertBefore);
} else {
MCall = CallInst::Create(MallocFunc, AllocSize, "malloccall");
Result = MCall;
if (Result->getType() != AllocPtrType) {
InsertAtEnd->getInstList().push_back(MCall);
// Create a cast instruction to convert to the right type...
Result = new BitCastInst(MCall, AllocPtrType, Name);
}
}
MCall->setTailCall();
if (Function *F = dyn_cast<Function>(MallocFunc)) {
MCall->setCallingConv(F->getCallingConv());
if (!F->doesNotAlias(0)) F->setDoesNotAlias(0);
}
assert(!MCall->getType()->isVoidTy() && "Malloc has void return type");
return Result;
}
/// CreateMalloc - Generate the IR for a call to malloc:
/// 1. Compute the malloc call's argument as the specified type's size,
/// possibly multiplied by the array size if the array size is not
/// constant 1.
/// 2. Call malloc with that argument.
/// 3. Bitcast the result of the malloc call to the specified type.
Instruction *CallInst::CreateMalloc(Instruction *InsertBefore,
Type *IntPtrTy, Type *AllocTy,
Value *AllocSize, Value *ArraySize,
Function * MallocF,
const Twine &Name) {
return createMalloc(InsertBefore, nullptr, IntPtrTy, AllocTy, AllocSize,
ArraySize, MallocF, Name);
}
/// CreateMalloc - Generate the IR for a call to malloc:
/// 1. Compute the malloc call's argument as the specified type's size,
/// possibly multiplied by the array size if the array size is not
/// constant 1.
/// 2. Call malloc with that argument.
/// 3. Bitcast the result of the malloc call to the specified type.
/// Note: This function does not add the bitcast to the basic block, that is the
/// responsibility of the caller.
Instruction *CallInst::CreateMalloc(BasicBlock *InsertAtEnd,
Type *IntPtrTy, Type *AllocTy,
Value *AllocSize, Value *ArraySize,
Function *MallocF, const Twine &Name) {
return createMalloc(nullptr, InsertAtEnd, IntPtrTy, AllocTy, AllocSize,
ArraySize, MallocF, Name);
}
static Instruction* createFree(Value* Source, Instruction *InsertBefore,
BasicBlock *InsertAtEnd) {
assert(((!InsertBefore && InsertAtEnd) || (InsertBefore && !InsertAtEnd)) &&
"createFree needs either InsertBefore or InsertAtEnd");
assert(Source->getType()->isPointerTy() &&
"Can not free something of nonpointer type!");
BasicBlock* BB = InsertBefore ? InsertBefore->getParent() : InsertAtEnd;
Module* M = BB->getParent()->getParent();
Type *VoidTy = Type::getVoidTy(M->getContext());
Type *IntPtrTy = Type::getInt8PtrTy(M->getContext());
// prototype free as "void free(void*)"
Value *FreeFunc = M->getOrInsertFunction("free", VoidTy, IntPtrTy, nullptr);
CallInst* Result = nullptr;
Value *PtrCast = Source;
if (InsertBefore) {
if (Source->getType() != IntPtrTy)
PtrCast = new BitCastInst(Source, IntPtrTy, "", InsertBefore);
Result = CallInst::Create(FreeFunc, PtrCast, "", InsertBefore);
} else {
if (Source->getType() != IntPtrTy)
PtrCast = new BitCastInst(Source, IntPtrTy, "", InsertAtEnd);
Result = CallInst::Create(FreeFunc, PtrCast, "");
}
Result->setTailCall();
if (Function *F = dyn_cast<Function>(FreeFunc))
Result->setCallingConv(F->getCallingConv());
return Result;
}
/// CreateFree - Generate the IR for a call to the builtin free function.
Instruction * CallInst::CreateFree(Value* Source, Instruction *InsertBefore) {
return createFree(Source, InsertBefore, nullptr);
}
/// CreateFree - Generate the IR for a call to the builtin free function.
/// Note: This function does not add the call to the basic block, that is the
/// responsibility of the caller.
Instruction* CallInst::CreateFree(Value* Source, BasicBlock *InsertAtEnd) {
Instruction* FreeCall = createFree(Source, nullptr, InsertAtEnd);
assert(FreeCall && "CreateFree did not create a CallInst");
return FreeCall;
}
//===----------------------------------------------------------------------===//
// InvokeInst Implementation
//===----------------------------------------------------------------------===//
void InvokeInst::init(FunctionType *FTy, Value *Fn, BasicBlock *IfNormal,
BasicBlock *IfException, ArrayRef<Value *> Args,
const Twine &NameStr) {
this->FTy = FTy;
assert(getNumOperands() == 3 + Args.size() && "NumOperands not set up?");
Op<-3>() = Fn;
Op<-2>() = IfNormal;
Op<-1>() = IfException;
#ifndef NDEBUG
assert(((Args.size() == FTy->getNumParams()) ||
(FTy->isVarArg() && Args.size() > FTy->getNumParams())) &&
"Invoking a function with bad signature");
for (unsigned i = 0, e = Args.size(); i != e; i++)
assert((i >= FTy->getNumParams() ||
FTy->getParamType(i) == Args[i]->getType()) &&
"Invoking a function with a bad signature!");
#endif
std::copy(Args.begin(), Args.end(), op_begin());
setName(NameStr);
}
InvokeInst::InvokeInst(const InvokeInst &II)
: TerminatorInst(II.getType(), Instruction::Invoke,
OperandTraits<InvokeInst>::op_end(this) -
II.getNumOperands(),
II.getNumOperands()),
AttributeList(II.AttributeList), FTy(II.FTy) {
setCallingConv(II.getCallingConv());
std::copy(II.op_begin(), II.op_end(), op_begin());
SubclassOptionalData = II.SubclassOptionalData;
}
BasicBlock *InvokeInst::getSuccessorV(unsigned idx) const {
return getSuccessor(idx);
}
unsigned InvokeInst::getNumSuccessorsV() const {
return getNumSuccessors();
}
void InvokeInst::setSuccessorV(unsigned idx, BasicBlock *B) {
return setSuccessor(idx, B);
}
bool InvokeInst::hasFnAttrImpl(Attribute::AttrKind A) const {
if (AttributeList.hasAttribute(AttributeSet::FunctionIndex, A))
return true;
if (const Function *F = getCalledFunction())
return F->getAttributes().hasAttribute(AttributeSet::FunctionIndex, A);
return false;
}
bool InvokeInst::paramHasAttr(unsigned i, Attribute::AttrKind A) const {
if (AttributeList.hasAttribute(i, A))
return true;
if (const Function *F = getCalledFunction())
return F->getAttributes().hasAttribute(i, A);
return false;
}
void InvokeInst::addAttribute(unsigned i, Attribute::AttrKind attr) {
AttributeSet PAL = getAttributes();
PAL = PAL.addAttribute(getContext(), i, attr);
setAttributes(PAL);
}
void InvokeInst::removeAttribute(unsigned i, Attribute attr) {
AttributeSet PAL = getAttributes();
AttrBuilder B(attr);
PAL = PAL.removeAttributes(getContext(), i,
AttributeSet::get(getContext(), i, B));
setAttributes(PAL);
}
void InvokeInst::addDereferenceableAttr(unsigned i, uint64_t Bytes) {
AttributeSet PAL = getAttributes();
PAL = PAL.addDereferenceableAttr(getContext(), i, Bytes);
setAttributes(PAL);
}
void InvokeInst::addDereferenceableOrNullAttr(unsigned i, uint64_t Bytes) {
AttributeSet PAL = getAttributes();
PAL = PAL.addDereferenceableOrNullAttr(getContext(), i, Bytes);
setAttributes(PAL);
}
LandingPadInst *InvokeInst::getLandingPadInst() const {
return cast<LandingPadInst>(getUnwindDest()->getFirstNonPHI());
}
//===----------------------------------------------------------------------===//
// ReturnInst Implementation
//===----------------------------------------------------------------------===//
ReturnInst::ReturnInst(const ReturnInst &RI)
: TerminatorInst(Type::getVoidTy(RI.getContext()), Instruction::Ret,
OperandTraits<ReturnInst>::op_end(this) -
RI.getNumOperands(),
RI.getNumOperands()) {
if (RI.getNumOperands())
Op<0>() = RI.Op<0>();
SubclassOptionalData = RI.SubclassOptionalData;
}
ReturnInst::ReturnInst(LLVMContext &C, Value *retVal, Instruction *InsertBefore)
: TerminatorInst(Type::getVoidTy(C), Instruction::Ret,
OperandTraits<ReturnInst>::op_end(this) - !!retVal, !!retVal,
InsertBefore) {
if (retVal)
Op<0>() = retVal;
}
ReturnInst::ReturnInst(LLVMContext &C, Value *retVal, BasicBlock *InsertAtEnd)
: TerminatorInst(Type::getVoidTy(C), Instruction::Ret,
OperandTraits<ReturnInst>::op_end(this) - !!retVal, !!retVal,
InsertAtEnd) {
if (retVal)
Op<0>() = retVal;
}
ReturnInst::ReturnInst(LLVMContext &Context, BasicBlock *InsertAtEnd)
: TerminatorInst(Type::getVoidTy(Context), Instruction::Ret,
OperandTraits<ReturnInst>::op_end(this), 0, InsertAtEnd) {
}
unsigned ReturnInst::getNumSuccessorsV() const {
return getNumSuccessors();
}
/// Out-of-line ReturnInst method, put here so the C++ compiler can choose to
/// emit the vtable for the class in this translation unit.
void ReturnInst::setSuccessorV(unsigned idx, BasicBlock *NewSucc) {
llvm_unreachable("ReturnInst has no successors!");
}
BasicBlock *ReturnInst::getSuccessorV(unsigned idx) const {
llvm_unreachable("ReturnInst has no successors!");
}
ReturnInst::~ReturnInst() {
}
//===----------------------------------------------------------------------===//
// ResumeInst Implementation
//===----------------------------------------------------------------------===//
ResumeInst::ResumeInst(const ResumeInst &RI)
: TerminatorInst(Type::getVoidTy(RI.getContext()), Instruction::Resume,
OperandTraits<ResumeInst>::op_begin(this), 1) {
Op<0>() = RI.Op<0>();
}
ResumeInst::ResumeInst(Value *Exn, Instruction *InsertBefore)
: TerminatorInst(Type::getVoidTy(Exn->getContext()), Instruction::Resume,
OperandTraits<ResumeInst>::op_begin(this), 1, InsertBefore) {
Op<0>() = Exn;
}
ResumeInst::ResumeInst(Value *Exn, BasicBlock *InsertAtEnd)
: TerminatorInst(Type::getVoidTy(Exn->getContext()), Instruction::Resume,
OperandTraits<ResumeInst>::op_begin(this), 1, InsertAtEnd) {
Op<0>() = Exn;
}
unsigned ResumeInst::getNumSuccessorsV() const {
return getNumSuccessors();
}
void ResumeInst::setSuccessorV(unsigned idx, BasicBlock *NewSucc) {
llvm_unreachable("ResumeInst has no successors!");
}
BasicBlock *ResumeInst::getSuccessorV(unsigned idx) const {
llvm_unreachable("ResumeInst has no successors!");
}
//===----------------------------------------------------------------------===//
// UnreachableInst Implementation
//===----------------------------------------------------------------------===//
UnreachableInst::UnreachableInst(LLVMContext &Context,
Instruction *InsertBefore)
: TerminatorInst(Type::getVoidTy(Context), Instruction::Unreachable,
nullptr, 0, InsertBefore) {
}
UnreachableInst::UnreachableInst(LLVMContext &Context, BasicBlock *InsertAtEnd)
: TerminatorInst(Type::getVoidTy(Context), Instruction::Unreachable,
nullptr, 0, InsertAtEnd) {
}
unsigned UnreachableInst::getNumSuccessorsV() const {
return getNumSuccessors();
}
void UnreachableInst::setSuccessorV(unsigned idx, BasicBlock *NewSucc) {
llvm_unreachable("UnreachableInst has no successors!");
}
BasicBlock *UnreachableInst::getSuccessorV(unsigned idx) const {
llvm_unreachable("UnreachableInst has no successors!");
}
//===----------------------------------------------------------------------===//
// BranchInst Implementation
//===----------------------------------------------------------------------===//
void BranchInst::AssertOK() {
if (isConditional())
assert(getCondition()->getType()->isIntegerTy(1) &&
"May only branch on boolean predicates!");
}
BranchInst::BranchInst(BasicBlock *IfTrue, Instruction *InsertBefore)
: TerminatorInst(Type::getVoidTy(IfTrue->getContext()), Instruction::Br,
OperandTraits<BranchInst>::op_end(this) - 1,
1, InsertBefore) {
assert(IfTrue && "Branch destination may not be null!");
Op<-1>() = IfTrue;
}
BranchInst::BranchInst(BasicBlock *IfTrue, BasicBlock *IfFalse, Value *Cond,
Instruction *InsertBefore)
: TerminatorInst(Type::getVoidTy(IfTrue->getContext()), Instruction::Br,
OperandTraits<BranchInst>::op_end(this) - 3,
3, InsertBefore) {
Op<-1>() = IfTrue;
Op<-2>() = IfFalse;
Op<-3>() = Cond;
#ifndef NDEBUG
AssertOK();
#endif
}
BranchInst::BranchInst(BasicBlock *IfTrue, BasicBlock *InsertAtEnd)
: TerminatorInst(Type::getVoidTy(IfTrue->getContext()), Instruction::Br,
OperandTraits<BranchInst>::op_end(this) - 1,
1, InsertAtEnd) {
assert(IfTrue && "Branch destination may not be null!");
Op<-1>() = IfTrue;
}
BranchInst::BranchInst(BasicBlock *IfTrue, BasicBlock *IfFalse, Value *Cond,
BasicBlock *InsertAtEnd)
: TerminatorInst(Type::getVoidTy(IfTrue->getContext()), Instruction::Br,
OperandTraits<BranchInst>::op_end(this) - 3,
3, InsertAtEnd) {
Op<-1>() = IfTrue;
Op<-2>() = IfFalse;
Op<-3>() = Cond;
#ifndef NDEBUG
AssertOK();
#endif
}
BranchInst::BranchInst(const BranchInst &BI) :
TerminatorInst(Type::getVoidTy(BI.getContext()), Instruction::Br,
OperandTraits<BranchInst>::op_end(this) - BI.getNumOperands(),
BI.getNumOperands()) {
Op<-1>() = BI.Op<-1>();
if (BI.getNumOperands() != 1) {
assert(BI.getNumOperands() == 3 && "BR can have 1 or 3 operands!");
Op<-3>() = BI.Op<-3>();
Op<-2>() = BI.Op<-2>();
}
SubclassOptionalData = BI.SubclassOptionalData;
}
void BranchInst::swapSuccessors() {
assert(isConditional() &&
"Cannot swap successors of an unconditional branch");
Op<-1>().swap(Op<-2>());
// Update profile metadata if present and it matches our structural
// expectations.
MDNode *ProfileData = getMetadata(LLVMContext::MD_prof);
if (!ProfileData || ProfileData->getNumOperands() != 3)
return;
// The first operand is the name. Fetch them backwards and build a new one.
Metadata *Ops[] = {ProfileData->getOperand(0), ProfileData->getOperand(2),
ProfileData->getOperand(1)};
setMetadata(LLVMContext::MD_prof,
MDNode::get(ProfileData->getContext(), Ops));
}
BasicBlock *BranchInst::getSuccessorV(unsigned idx) const {
return getSuccessor(idx);
}
unsigned BranchInst::getNumSuccessorsV() const {
return getNumSuccessors();
}
void BranchInst::setSuccessorV(unsigned idx, BasicBlock *B) {
setSuccessor(idx, B);
}
//===----------------------------------------------------------------------===//
// AllocaInst Implementation
//===----------------------------------------------------------------------===//
static Value *getAISize(LLVMContext &Context, Value *Amt) {
if (!Amt)
Amt = ConstantInt::get(Type::getInt32Ty(Context), 1);
else {
assert(!isa<BasicBlock>(Amt) &&
"Passed basic block into allocation size parameter! Use other ctor");
assert(Amt->getType()->isIntegerTy() &&
"Allocation array size is not an integer!");
}
return Amt;
}
AllocaInst::AllocaInst(Type *Ty, const Twine &Name, Instruction *InsertBefore)
: AllocaInst(Ty, /*ArraySize=*/nullptr, Name, InsertBefore) {}
AllocaInst::AllocaInst(Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd)
: AllocaInst(Ty, /*ArraySize=*/nullptr, Name, InsertAtEnd) {}
AllocaInst::AllocaInst(Type *Ty, Value *ArraySize, const Twine &Name,
Instruction *InsertBefore)
: AllocaInst(Ty, ArraySize, /*Align=*/0, Name, InsertBefore) {}
AllocaInst::AllocaInst(Type *Ty, Value *ArraySize, const Twine &Name,
BasicBlock *InsertAtEnd)
: AllocaInst(Ty, ArraySize, /*Align=*/0, Name, InsertAtEnd) {}
AllocaInst::AllocaInst(Type *Ty, Value *ArraySize, unsigned Align,
const Twine &Name, Instruction *InsertBefore)
: UnaryInstruction(PointerType::getUnqual(Ty), Alloca,
getAISize(Ty->getContext(), ArraySize), InsertBefore),
AllocatedType(Ty) {
setAlignment(Align);
assert(!Ty->isVoidTy() && "Cannot allocate void!");
setName(Name);
}
AllocaInst::AllocaInst(Type *Ty, Value *ArraySize, unsigned Align,
const Twine &Name, BasicBlock *InsertAtEnd)
: UnaryInstruction(PointerType::getUnqual(Ty), Alloca,
getAISize(Ty->getContext(), ArraySize), InsertAtEnd),
AllocatedType(Ty) {
setAlignment(Align);
assert(!Ty->isVoidTy() && "Cannot allocate void!");
setName(Name);
}
// Out of line virtual method, so the vtable, etc has a home.
AllocaInst::~AllocaInst() {
}
void AllocaInst::setAlignment(unsigned Align) {
assert((Align & (Align-1)) == 0 && "Alignment is not a power of 2!");
assert(Align <= MaximumAlignment &&
"Alignment is greater than MaximumAlignment!");
setInstructionSubclassData((getSubclassDataFromInstruction() & ~31) |
(Log2_32(Align) + 1));
assert(getAlignment() == Align && "Alignment representation error!");
}
bool AllocaInst::isArrayAllocation() const {
if (ConstantInt *CI = dyn_cast<ConstantInt>(getOperand(0)))
return !CI->isOne();
return true;
}
/// isStaticAlloca - Return true if this alloca is in the entry block of the
/// function and is a constant size. If so, the code generator will fold it
/// into the prolog/epilog code, so it is basically free.
bool AllocaInst::isStaticAlloca() const {
// Must be constant size.
if (!isa<ConstantInt>(getArraySize())) return false;
// Must be in the entry block.
const BasicBlock *Parent = getParent();
return Parent == &Parent->getParent()->front() && !isUsedWithInAlloca();
}
//===----------------------------------------------------------------------===//
// LoadInst Implementation
//===----------------------------------------------------------------------===//
void LoadInst::AssertOK() {
assert(getOperand(0)->getType()->isPointerTy() &&
"Ptr must have pointer type.");
assert(!(isAtomic() && getAlignment() == 0) &&
"Alignment required for atomic load");
}
LoadInst::LoadInst(Value *Ptr, const Twine &Name, Instruction *InsertBef)
: LoadInst(Ptr, Name, /*isVolatile=*/false, InsertBef) {}
LoadInst::LoadInst(Value *Ptr, const Twine &Name, BasicBlock *InsertAE)
: LoadInst(Ptr, Name, /*isVolatile=*/false, InsertAE) {}
LoadInst::LoadInst(Type *Ty, Value *Ptr, const Twine &Name, bool isVolatile,
Instruction *InsertBef)
: LoadInst(Ty, Ptr, Name, isVolatile, /*Align=*/0, InsertBef) {}
LoadInst::LoadInst(Value *Ptr, const Twine &Name, bool isVolatile,
BasicBlock *InsertAE)
: LoadInst(Ptr, Name, isVolatile, /*Align=*/0, InsertAE) {}
LoadInst::LoadInst(Type *Ty, Value *Ptr, const Twine &Name, bool isVolatile,
unsigned Align, Instruction *InsertBef)
: LoadInst(Ty, Ptr, Name, isVolatile, Align, NotAtomic, CrossThread,
InsertBef) {}
LoadInst::LoadInst(Value *Ptr, const Twine &Name, bool isVolatile,
unsigned Align, BasicBlock *InsertAE)
: LoadInst(Ptr, Name, isVolatile, Align, NotAtomic, CrossThread, InsertAE) {
}
LoadInst::LoadInst(Type *Ty, Value *Ptr, const Twine &Name, bool isVolatile,
unsigned Align, AtomicOrdering Order,
SynchronizationScope SynchScope, Instruction *InsertBef)
: UnaryInstruction(Ty, Load, Ptr, InsertBef) {
assert(Ty == cast<PointerType>(Ptr->getType())->getElementType());
setVolatile(isVolatile);
setAlignment(Align);
setAtomic(Order, SynchScope);
AssertOK();
setName(Name);
}
LoadInst::LoadInst(Value *Ptr, const Twine &Name, bool isVolatile,
unsigned Align, AtomicOrdering Order,
SynchronizationScope SynchScope,
BasicBlock *InsertAE)
: UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
Load, Ptr, InsertAE) {
setVolatile(isVolatile);
setAlignment(Align);
setAtomic(Order, SynchScope);
AssertOK();
setName(Name);
}
LoadInst::LoadInst(Value *Ptr, const char *Name, Instruction *InsertBef)
: UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
Load, Ptr, InsertBef) {
setVolatile(false);
setAlignment(0);
setAtomic(NotAtomic);
AssertOK();
if (Name && Name[0]) setName(Name);
}
LoadInst::LoadInst(Value *Ptr, const char *Name, BasicBlock *InsertAE)
: UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
Load, Ptr, InsertAE) {
setVolatile(false);
setAlignment(0);
setAtomic(NotAtomic);
AssertOK();
if (Name && Name[0]) setName(Name);
}
LoadInst::LoadInst(Type *Ty, Value *Ptr, const char *Name, bool isVolatile,
Instruction *InsertBef)
: UnaryInstruction(Ty, Load, Ptr, InsertBef) {
assert(Ty == cast<PointerType>(Ptr->getType())->getElementType());
setVolatile(isVolatile);
setAlignment(0);
setAtomic(NotAtomic);
AssertOK();
if (Name && Name[0]) setName(Name);
}
LoadInst::LoadInst(Value *Ptr, const char *Name, bool isVolatile,
BasicBlock *InsertAE)
: UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
Load, Ptr, InsertAE) {
setVolatile(isVolatile);
setAlignment(0);
setAtomic(NotAtomic);
AssertOK();
if (Name && Name[0]) setName(Name);
}
void LoadInst::setAlignment(unsigned Align) {
assert((Align & (Align-1)) == 0 && "Alignment is not a power of 2!");
assert(Align <= MaximumAlignment &&
"Alignment is greater than MaximumAlignment!");
setInstructionSubclassData((getSubclassDataFromInstruction() & ~(31 << 1)) |
((Log2_32(Align)+1)<<1));
assert(getAlignment() == Align && "Alignment representation error!");
}
//===----------------------------------------------------------------------===//
// StoreInst Implementation
//===----------------------------------------------------------------------===//
void StoreInst::AssertOK() {
assert(getOperand(0) && getOperand(1) && "Both operands must be non-null!");
assert(getOperand(1)->getType()->isPointerTy() &&
"Ptr must have pointer type!");
assert(getOperand(0)->getType() ==
cast<PointerType>(getOperand(1)->getType())->getElementType()
&& "Ptr must be a pointer to Val type!");
assert(!(isAtomic() && getAlignment() == 0) &&
"Alignment required for atomic store");
}
StoreInst::StoreInst(Value *val, Value *addr, Instruction *InsertBefore)
: StoreInst(val, addr, /*isVolatile=*/false, InsertBefore) {}
StoreInst::StoreInst(Value *val, Value *addr, BasicBlock *InsertAtEnd)
: StoreInst(val, addr, /*isVolatile=*/false, InsertAtEnd) {}
StoreInst::StoreInst(Value *val, Value *addr, bool isVolatile,
Instruction *InsertBefore)
: StoreInst(val, addr, isVolatile, /*Align=*/0, InsertBefore) {}
StoreInst::StoreInst(Value *val, Value *addr, bool isVolatile,
BasicBlock *InsertAtEnd)
: StoreInst(val, addr, isVolatile, /*Align=*/0, InsertAtEnd) {}
StoreInst::StoreInst(Value *val, Value *addr, bool isVolatile, unsigned Align,
Instruction *InsertBefore)
: StoreInst(val, addr, isVolatile, Align, NotAtomic, CrossThread,
InsertBefore) {}
StoreInst::StoreInst(Value *val, Value *addr, bool isVolatile, unsigned Align,
BasicBlock *InsertAtEnd)
: StoreInst(val, addr, isVolatile, Align, NotAtomic, CrossThread,
InsertAtEnd) {}
StoreInst::StoreInst(Value *val, Value *addr, bool isVolatile,
unsigned Align, AtomicOrdering Order,
SynchronizationScope SynchScope,
Instruction *InsertBefore)
: Instruction(Type::getVoidTy(val->getContext()), Store,
OperandTraits<StoreInst>::op_begin(this),
OperandTraits<StoreInst>::operands(this),
InsertBefore) {
Op<0>() = val;
Op<1>() = addr;
setVolatile(isVolatile);
setAlignment(Align);
setAtomic(Order, SynchScope);
AssertOK();
}
StoreInst::StoreInst(Value *val, Value *addr, bool isVolatile,
unsigned Align, AtomicOrdering Order,
SynchronizationScope SynchScope,
BasicBlock *InsertAtEnd)
: Instruction(Type::getVoidTy(val->getContext()), Store,
OperandTraits<StoreInst>::op_begin(this),
OperandTraits<StoreInst>::operands(this),
InsertAtEnd) {
Op<0>() = val;
Op<1>() = addr;
setVolatile(isVolatile);
setAlignment(Align);
setAtomic(Order, SynchScope);
AssertOK();
}
void StoreInst::setAlignment(unsigned Align) {
assert((Align & (Align-1)) == 0 && "Alignment is not a power of 2!");
assert(Align <= MaximumAlignment &&
"Alignment is greater than MaximumAlignment!");
setInstructionSubclassData((getSubclassDataFromInstruction() & ~(31 << 1)) |
((Log2_32(Align)+1) << 1));
assert(getAlignment() == Align && "Alignment representation error!");
}
//===----------------------------------------------------------------------===//
// AtomicCmpXchgInst Implementation
//===----------------------------------------------------------------------===//
void AtomicCmpXchgInst::Init(Value *Ptr, Value *Cmp, Value *NewVal,
AtomicOrdering SuccessOrdering,
AtomicOrdering FailureOrdering,
SynchronizationScope SynchScope) {
Op<0>() = Ptr;
Op<1>() = Cmp;
Op<2>() = NewVal;
setSuccessOrdering(SuccessOrdering);
setFailureOrdering(FailureOrdering);
setSynchScope(SynchScope);
assert(getOperand(0) && getOperand(1) && getOperand(2) &&
"All operands must be non-null!");
assert(getOperand(0)->getType()->isPointerTy() &&
"Ptr must have pointer type!");
assert(getOperand(1)->getType() ==
cast<PointerType>(getOperand(0)->getType())->getElementType()
&& "Ptr must be a pointer to Cmp type!");
assert(getOperand(2)->getType() ==
cast<PointerType>(getOperand(0)->getType())->getElementType()
&& "Ptr must be a pointer to NewVal type!");
assert(SuccessOrdering != NotAtomic &&
"AtomicCmpXchg instructions must be atomic!");
assert(FailureOrdering != NotAtomic &&
"AtomicCmpXchg instructions must be atomic!");
assert(SuccessOrdering >= FailureOrdering &&
"AtomicCmpXchg success ordering must be at least as strong as fail");
assert(FailureOrdering != Release && FailureOrdering != AcquireRelease &&
"AtomicCmpXchg failure ordering cannot include release semantics");
}
AtomicCmpXchgInst::AtomicCmpXchgInst(Value *Ptr, Value *Cmp, Value *NewVal,
AtomicOrdering SuccessOrdering,
AtomicOrdering FailureOrdering,
SynchronizationScope SynchScope,
Instruction *InsertBefore)
: Instruction(
StructType::get(Cmp->getType(), Type::getInt1Ty(Cmp->getContext()),
nullptr),
AtomicCmpXchg, OperandTraits<AtomicCmpXchgInst>::op_begin(this),
OperandTraits<AtomicCmpXchgInst>::operands(this), InsertBefore) {
Init(Ptr, Cmp, NewVal, SuccessOrdering, FailureOrdering, SynchScope);
}
AtomicCmpXchgInst::AtomicCmpXchgInst(Value *Ptr, Value *Cmp, Value *NewVal,
AtomicOrdering SuccessOrdering,
AtomicOrdering FailureOrdering,
SynchronizationScope SynchScope,
BasicBlock *InsertAtEnd)
: Instruction(
StructType::get(Cmp->getType(), Type::getInt1Ty(Cmp->getContext()),
nullptr),
AtomicCmpXchg, OperandTraits<AtomicCmpXchgInst>::op_begin(this),
OperandTraits<AtomicCmpXchgInst>::operands(this), InsertAtEnd) {
Init(Ptr, Cmp, NewVal, SuccessOrdering, FailureOrdering, SynchScope);
}
//===----------------------------------------------------------------------===//
// AtomicRMWInst Implementation
//===----------------------------------------------------------------------===//
void AtomicRMWInst::Init(BinOp Operation, Value *Ptr, Value *Val,
AtomicOrdering Ordering,
SynchronizationScope SynchScope) {
Op<0>() = Ptr;
Op<1>() = Val;
setOperation(Operation);
setOrdering(Ordering);
setSynchScope(SynchScope);
assert(getOperand(0) && getOperand(1) &&
"All operands must be non-null!");
assert(getOperand(0)->getType()->isPointerTy() &&
"Ptr must have pointer type!");
assert(getOperand(1)->getType() ==
cast<PointerType>(getOperand(0)->getType())->getElementType()
&& "Ptr must be a pointer to Val type!");
assert(Ordering != NotAtomic &&
"AtomicRMW instructions must be atomic!");
}
AtomicRMWInst::AtomicRMWInst(BinOp Operation, Value *Ptr, Value *Val,
AtomicOrdering Ordering,
SynchronizationScope SynchScope,
Instruction *InsertBefore)
: Instruction(Val->getType(), AtomicRMW,
OperandTraits<AtomicRMWInst>::op_begin(this),
OperandTraits<AtomicRMWInst>::operands(this),
InsertBefore) {
Init(Operation, Ptr, Val, Ordering, SynchScope);
}
AtomicRMWInst::AtomicRMWInst(BinOp Operation, Value *Ptr, Value *Val,
AtomicOrdering Ordering,
SynchronizationScope SynchScope,
BasicBlock *InsertAtEnd)
: Instruction(Val->getType(), AtomicRMW,
OperandTraits<AtomicRMWInst>::op_begin(this),
OperandTraits<AtomicRMWInst>::operands(this),
InsertAtEnd) {
Init(Operation, Ptr, Val, Ordering, SynchScope);
}
//===----------------------------------------------------------------------===//
// FenceInst Implementation
//===----------------------------------------------------------------------===//
FenceInst::FenceInst(LLVMContext &C, AtomicOrdering Ordering,
SynchronizationScope SynchScope,
Instruction *InsertBefore)
: Instruction(Type::getVoidTy(C), Fence, nullptr, 0, InsertBefore) {
setOrdering(Ordering);
setSynchScope(SynchScope);
}
FenceInst::FenceInst(LLVMContext &C, AtomicOrdering Ordering,
SynchronizationScope SynchScope,
BasicBlock *InsertAtEnd)
: Instruction(Type::getVoidTy(C), Fence, nullptr, 0, InsertAtEnd) {
setOrdering(Ordering);
setSynchScope(SynchScope);
}
//===----------------------------------------------------------------------===//
// GetElementPtrInst Implementation
//===----------------------------------------------------------------------===//
void GetElementPtrInst::init(Value *Ptr, ArrayRef<Value *> IdxList,
const Twine &Name) {
assert(getNumOperands() == 1 + IdxList.size() &&
"NumOperands not initialized?");
Op<0>() = Ptr;
std::copy(IdxList.begin(), IdxList.end(), op_begin() + 1);
setName(Name);
}
GetElementPtrInst::GetElementPtrInst(const GetElementPtrInst &GEPI)
: Instruction(GEPI.getType(), GetElementPtr,
OperandTraits<GetElementPtrInst>::op_end(this) -
GEPI.getNumOperands(),
GEPI.getNumOperands()),
SourceElementType(GEPI.SourceElementType),
ResultElementType(GEPI.ResultElementType) {
std::copy(GEPI.op_begin(), GEPI.op_end(), op_begin());
SubclassOptionalData = GEPI.SubclassOptionalData;
}
/// getIndexedType - Returns the type of the element that would be accessed with
/// a gep instruction with the specified parameters.
///
/// The Idxs pointer should point to a continuous piece of memory containing the
/// indices, either as Value* or uint64_t.
///
/// A null type is returned if the indices are invalid for the specified
/// pointer type.
///
template <typename IndexTy>
static Type *getIndexedTypeInternal(Type *Agg, ArrayRef<IndexTy> IdxList) {
// Handle the special case of the empty set index set, which is always valid.
if (IdxList.empty())
return Agg;
// If there is at least one index, the top level type must be sized, otherwise
// it cannot be 'stepped over'.
if (!Agg->isSized())
return nullptr;
unsigned CurIdx = 1;
for (; CurIdx != IdxList.size(); ++CurIdx) {
CompositeType *CT = dyn_cast<CompositeType>(Agg);
if (!CT || CT->isPointerTy()) return nullptr;
IndexTy Index = IdxList[CurIdx];
if (!CT->indexValid(Index)) return nullptr;
Agg = CT->getTypeAtIndex(Index);
}
return CurIdx == IdxList.size() ? Agg : nullptr;
}
Type *GetElementPtrInst::getIndexedType(Type *Ty, ArrayRef<Value *> IdxList) {
return getIndexedTypeInternal(Ty, IdxList);
}
Type *GetElementPtrInst::getIndexedType(Type *Ty,
ArrayRef<Constant *> IdxList) {
return getIndexedTypeInternal(Ty, IdxList);
}
Type *GetElementPtrInst::getIndexedType(Type *Ty, ArrayRef<uint64_t> IdxList) {
return getIndexedTypeInternal(Ty, IdxList);
}
/// hasAllZeroIndices - Return true if all of the indices of this GEP are
/// zeros. If so, the result pointer and the first operand have the same
/// value, just potentially different types.
bool GetElementPtrInst::hasAllZeroIndices() const {
for (unsigned i = 1, e = getNumOperands(); i != e; ++i) {
if (ConstantInt *CI = dyn_cast<ConstantInt>(getOperand(i))) {
if (!CI->isZero()) return false;
} else {
return false;
}
}
return true;
}
/// hasAllConstantIndices - Return true if all of the indices of this GEP are
/// constant integers. If so, the result pointer and the first operand have
/// a constant offset between them.
bool GetElementPtrInst::hasAllConstantIndices() const {
for (unsigned i = 1, e = getNumOperands(); i != e; ++i) {
if (!isa<ConstantInt>(getOperand(i)))
return false;
}
return true;
}
void GetElementPtrInst::setIsInBounds(bool B) {
cast<GEPOperator>(this)->setIsInBounds(B);
}
bool GetElementPtrInst::isInBounds() const {
return cast<GEPOperator>(this)->isInBounds();
}
bool GetElementPtrInst::accumulateConstantOffset(const DataLayout &DL,
APInt &Offset) const {
// Delegate to the generic GEPOperator implementation.
return cast<GEPOperator>(this)->accumulateConstantOffset(DL, Offset);
}
//===----------------------------------------------------------------------===//
// ExtractElementInst Implementation
//===----------------------------------------------------------------------===//
ExtractElementInst::ExtractElementInst(Value *Val, Value *Index,
const Twine &Name,
Instruction *InsertBef)
: Instruction(cast<VectorType>(Val->getType())->getElementType(),
ExtractElement,
OperandTraits<ExtractElementInst>::op_begin(this),
2, InsertBef) {
assert(isValidOperands(Val, Index) &&
"Invalid extractelement instruction operands!");
Op<0>() = Val;
Op<1>() = Index;
setName(Name);
}
ExtractElementInst::ExtractElementInst(Value *Val, Value *Index,
const Twine &Name,
BasicBlock *InsertAE)
: Instruction(cast<VectorType>(Val->getType())->getElementType(),
ExtractElement,
OperandTraits<ExtractElementInst>::op_begin(this),
2, InsertAE) {
assert(isValidOperands(Val, Index) &&
"Invalid extractelement instruction operands!");
Op<0>() = Val;
Op<1>() = Index;
setName(Name);
}
bool ExtractElementInst::isValidOperands(const Value *Val, const Value *Index) {
if (!Val->getType()->isVectorTy() || !Index->getType()->isIntegerTy())
return false;
return true;
}
//===----------------------------------------------------------------------===//
// InsertElementInst Implementation
//===----------------------------------------------------------------------===//
InsertElementInst::InsertElementInst(Value *Vec, Value *Elt, Value *Index,
const Twine &Name,
Instruction *InsertBef)
: Instruction(Vec->getType(), InsertElement,
OperandTraits<InsertElementInst>::op_begin(this),
3, InsertBef) {
assert(isValidOperands(Vec, Elt, Index) &&
"Invalid insertelement instruction operands!");
Op<0>() = Vec;
Op<1>() = Elt;
Op<2>() = Index;
setName(Name);
}
InsertElementInst::InsertElementInst(Value *Vec, Value *Elt, Value *Index,
const Twine &Name,
BasicBlock *InsertAE)
: Instruction(Vec->getType(), InsertElement,
OperandTraits<InsertElementInst>::op_begin(this),
3, InsertAE) {
assert(isValidOperands(Vec, Elt, Index) &&
"Invalid insertelement instruction operands!");
Op<0>() = Vec;
Op<1>() = Elt;
Op<2>() = Index;
setName(Name);
}
bool InsertElementInst::isValidOperands(const Value *Vec, const Value *Elt,
const Value *Index) {
if (!Vec->getType()->isVectorTy())
return false; // First operand of insertelement must be vector type.
if (Elt->getType() != cast<VectorType>(Vec->getType())->getElementType())
return false;// Second operand of insertelement must be vector element type.
if (!Index->getType()->isIntegerTy())
return false; // Third operand of insertelement must be i32.
return true;
}
//===----------------------------------------------------------------------===//
// ShuffleVectorInst Implementation
//===----------------------------------------------------------------------===//
ShuffleVectorInst::ShuffleVectorInst(Value *V1, Value *V2, Value *Mask,
const Twine &Name,
Instruction *InsertBefore)
: Instruction(VectorType::get(cast<VectorType>(V1->getType())->getElementType(),
cast<VectorType>(Mask->getType())->getNumElements()),
ShuffleVector,
OperandTraits<ShuffleVectorInst>::op_begin(this),
OperandTraits<ShuffleVectorInst>::operands(this),
InsertBefore) {
assert(isValidOperands(V1, V2, Mask) &&
"Invalid shuffle vector instruction operands!");
Op<0>() = V1;
Op<1>() = V2;
Op<2>() = Mask;
setName(Name);
}
ShuffleVectorInst::ShuffleVectorInst(Value *V1, Value *V2, Value *Mask,
const Twine &Name,
BasicBlock *InsertAtEnd)
: Instruction(VectorType::get(cast<VectorType>(V1->getType())->getElementType(),
cast<VectorType>(Mask->getType())->getNumElements()),
ShuffleVector,
OperandTraits<ShuffleVectorInst>::op_begin(this),
OperandTraits<ShuffleVectorInst>::operands(this),
InsertAtEnd) {
assert(isValidOperands(V1, V2, Mask) &&
"Invalid shuffle vector instruction operands!");
Op<0>() = V1;
Op<1>() = V2;
Op<2>() = Mask;
setName(Name);
}
bool ShuffleVectorInst::isValidOperands(const Value *V1, const Value *V2,
const Value *Mask) {
// V1 and V2 must be vectors of the same type.
if (!V1->getType()->isVectorTy() || V1->getType() != V2->getType())
return false;
// Mask must be vector of i32.
VectorType *MaskTy = dyn_cast<VectorType>(Mask->getType());
if (!MaskTy || !MaskTy->getElementType()->isIntegerTy(32))
return false;
// Check to see if Mask is valid.
if (isa<UndefValue>(Mask) || isa<ConstantAggregateZero>(Mask))
return true;
if (const ConstantVector *MV = dyn_cast<ConstantVector>(Mask)) {
unsigned V1Size = cast<VectorType>(V1->getType())->getNumElements();
for (Value *Op : MV->operands()) {
if (ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
if (CI->uge(V1Size*2))
return false;
} else if (!isa<UndefValue>(Op)) {
return false;
}
}
return true;
}
if (const ConstantDataSequential *CDS =
dyn_cast<ConstantDataSequential>(Mask)) {
unsigned V1Size = cast<VectorType>(V1->getType())->getNumElements();
for (unsigned i = 0, e = MaskTy->getNumElements(); i != e; ++i)
if (CDS->getElementAsInteger(i) >= V1Size*2)
return false;
return true;
}
// The bitcode reader can create a place holder for a forward reference
// used as the shuffle mask. When this occurs, the shuffle mask will
// fall into this case and fail. To avoid this error, do this bit of
// ugliness to allow such a mask pass.
if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(Mask))
if (CE->getOpcode() == Instruction::UserOp1)
return true;
return false;
}
/// getMaskValue - Return the index from the shuffle mask for the specified
/// output result. This is either -1 if the element is undef or a number less
/// than 2*numelements.
int ShuffleVectorInst::getMaskValue(Constant *Mask, unsigned i) {
assert(i < Mask->getType()->getVectorNumElements() && "Index out of range");
if (ConstantDataSequential *CDS =dyn_cast<ConstantDataSequential>(Mask))
return CDS->getElementAsInteger(i);
Constant *C = Mask->getAggregateElement(i);
if (isa<UndefValue>(C))
return -1;
return cast<ConstantInt>(C)->getZExtValue();
}
/// getShuffleMask - Return the full mask for this instruction, where each
/// element is the element number and undef's are returned as -1.
void ShuffleVectorInst::getShuffleMask(Constant *Mask,
SmallVectorImpl<int> &Result) {
unsigned NumElts = Mask->getType()->getVectorNumElements();
if (ConstantDataSequential *CDS=dyn_cast<ConstantDataSequential>(Mask)) {
for (unsigned i = 0; i != NumElts; ++i)
Result.push_back(CDS->getElementAsInteger(i));
return;
}
for (unsigned i = 0; i != NumElts; ++i) {
Constant *C = Mask->getAggregateElement(i);
Result.push_back(isa<UndefValue>(C) ? -1 :
cast<ConstantInt>(C)->getZExtValue());
}
}
//===----------------------------------------------------------------------===//
// InsertValueInst Class
//===----------------------------------------------------------------------===//
void InsertValueInst::init(Value *Agg, Value *Val, ArrayRef<unsigned> Idxs,
const Twine &Name) {
assert(getNumOperands() == 2 && "NumOperands not initialized?");
// There's no fundamental reason why we require at least one index
// (other than weirdness with &*IdxBegin being invalid; see
// getelementptr's init routine for example). But there's no
// present need to support it.
assert(Idxs.size() > 0 && "InsertValueInst must have at least one index");
assert(ExtractValueInst::getIndexedType(Agg->getType(), Idxs) ==
Val->getType() && "Inserted value must match indexed type!");
Op<0>() = Agg;
Op<1>() = Val;
Indices.append(Idxs.begin(), Idxs.end());
setName(Name);
}
InsertValueInst::InsertValueInst(const InsertValueInst &IVI)
: Instruction(IVI.getType(), InsertValue,
OperandTraits<InsertValueInst>::op_begin(this), 2),
Indices(IVI.Indices) {
Op<0>() = IVI.getOperand(0);
Op<1>() = IVI.getOperand(1);
SubclassOptionalData = IVI.SubclassOptionalData;
}
//===----------------------------------------------------------------------===//
// ExtractValueInst Class
//===----------------------------------------------------------------------===//
void ExtractValueInst::init(ArrayRef<unsigned> Idxs, const Twine &Name) {
assert(getNumOperands() == 1 && "NumOperands not initialized?");
// There's no fundamental reason why we require at least one index.
// But there's no present need to support it.
assert(Idxs.size() > 0 && "ExtractValueInst must have at least one index");
Indices.append(Idxs.begin(), Idxs.end());
setName(Name);
}
ExtractValueInst::ExtractValueInst(const ExtractValueInst &EVI)
: UnaryInstruction(EVI.getType(), ExtractValue, EVI.getOperand(0)),
Indices(EVI.Indices) {
SubclassOptionalData = EVI.SubclassOptionalData;
}
// getIndexedType - Returns the type of the element that would be extracted
// with an extractvalue instruction with the specified parameters.
//
// A null type is returned if the indices are invalid for the specified
// pointer type.
//
Type *ExtractValueInst::getIndexedType(Type *Agg,
ArrayRef<unsigned> Idxs) {
for (unsigned Index : Idxs) {
// We can't use CompositeType::indexValid(Index) here.
// indexValid() always returns true for arrays because getelementptr allows
// out-of-bounds indices. Since we don't allow those for extractvalue and
// insertvalue we need to check array indexing manually.
// Since the only other types we can index into are struct types it's just
// as easy to check those manually as well.
if (ArrayType *AT = dyn_cast<ArrayType>(Agg)) {
if (Index >= AT->getNumElements())
return nullptr;
} else if (StructType *ST = dyn_cast<StructType>(Agg)) {
if (Index >= ST->getNumElements())
return nullptr;
} else {
// Not a valid type to index into.
return nullptr;
}
Agg = cast<CompositeType>(Agg)->getTypeAtIndex(Index);
}
return const_cast<Type*>(Agg);
}
//===----------------------------------------------------------------------===//
// BinaryOperator Class
//===----------------------------------------------------------------------===//
BinaryOperator::BinaryOperator(BinaryOps iType, Value *S1, Value *S2,
Type *Ty, const Twine &Name,
Instruction *InsertBefore)
: Instruction(Ty, iType,
OperandTraits<BinaryOperator>::op_begin(this),
OperandTraits<BinaryOperator>::operands(this),
InsertBefore) {
Op<0>() = S1;
Op<1>() = S2;
init(iType);
setName(Name);
}
BinaryOperator::BinaryOperator(BinaryOps iType, Value *S1, Value *S2,
Type *Ty, const Twine &Name,
BasicBlock *InsertAtEnd)
: Instruction(Ty, iType,
OperandTraits<BinaryOperator>::op_begin(this),
OperandTraits<BinaryOperator>::operands(this),
InsertAtEnd) {
Op<0>() = S1;
Op<1>() = S2;
init(iType);
setName(Name);
}
void BinaryOperator::init(BinaryOps iType) {
Value *LHS = getOperand(0), *RHS = getOperand(1);
(void)LHS; (void)RHS; // Silence warnings.
assert(LHS->getType() == RHS->getType() &&
"Binary operator operand types must match!");
#ifndef NDEBUG
switch (iType) {
case Add: case Sub:
case Mul:
assert(getType() == LHS->getType() &&
"Arithmetic operation should return same type as operands!");
assert(getType()->isIntOrIntVectorTy() &&
"Tried to create an integer operation on a non-integer type!");
break;
case FAdd: case FSub:
case FMul:
assert(getType() == LHS->getType() &&
"Arithmetic operation should return same type as operands!");
assert(getType()->isFPOrFPVectorTy() &&
"Tried to create a floating-point operation on a "
"non-floating-point type!");
break;
case UDiv:
case SDiv:
assert(getType() == LHS->getType() &&
"Arithmetic operation should return same type as operands!");
assert((getType()->isIntegerTy() || (getType()->isVectorTy() &&
cast<VectorType>(getType())->getElementType()->isIntegerTy())) &&
"Incorrect operand type (not integer) for S/UDIV");
break;
case FDiv:
assert(getType() == LHS->getType() &&
"Arithmetic operation should return same type as operands!");
assert(getType()->isFPOrFPVectorTy() &&
"Incorrect operand type (not floating point) for FDIV");
break;
case URem:
case SRem:
assert(getType() == LHS->getType() &&
"Arithmetic operation should return same type as operands!");
assert((getType()->isIntegerTy() || (getType()->isVectorTy() &&
cast<VectorType>(getType())->getElementType()->isIntegerTy())) &&
"Incorrect operand type (not integer) for S/UREM");
break;
case FRem:
assert(getType() == LHS->getType() &&
"Arithmetic operation should return same type as operands!");
assert(getType()->isFPOrFPVectorTy() &&
"Incorrect operand type (not floating point) for FREM");
break;
case Shl:
case LShr:
case AShr:
assert(getType() == LHS->getType() &&
"Shift operation should return same type as operands!");
assert((getType()->isIntegerTy() ||
(getType()->isVectorTy() &&
cast<VectorType>(getType())->getElementType()->isIntegerTy())) &&
"Tried to create a shift operation on a non-integral type!");
break;
case And: case Or:
case Xor:
assert(getType() == LHS->getType() &&
"Logical operation should return same type as operands!");
assert((getType()->isIntegerTy() ||
(getType()->isVectorTy() &&
cast<VectorType>(getType())->getElementType()->isIntegerTy())) &&
"Tried to create a logical operation on a non-integral type!");
break;
default:
break;
}
#endif
}
BinaryOperator *BinaryOperator::Create(BinaryOps Op, Value *S1, Value *S2,
const Twine &Name,
Instruction *InsertBefore) {
assert(S1->getType() == S2->getType() &&
"Cannot create binary operator with two operands of differing type!");
return new BinaryOperator(Op, S1, S2, S1->getType(), Name, InsertBefore);
}
BinaryOperator *BinaryOperator::Create(BinaryOps Op, Value *S1, Value *S2,
const Twine &Name,
BasicBlock *InsertAtEnd) {
BinaryOperator *Res = Create(Op, S1, S2, Name);
InsertAtEnd->getInstList().push_back(Res);
return Res;
}
BinaryOperator *BinaryOperator::CreateNeg(Value *Op, const Twine &Name,
Instruction *InsertBefore) {
Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
return new BinaryOperator(Instruction::Sub,
zero, Op,
Op->getType(), Name, InsertBefore);
}
BinaryOperator *BinaryOperator::CreateNeg(Value *Op, const Twine &Name,
BasicBlock *InsertAtEnd) {
Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
return new BinaryOperator(Instruction::Sub,
zero, Op,
Op->getType(), Name, InsertAtEnd);
}
BinaryOperator *BinaryOperator::CreateNSWNeg(Value *Op, const Twine &Name,
Instruction *InsertBefore) {
Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
return BinaryOperator::CreateNSWSub(zero, Op, Name, InsertBefore);
}
BinaryOperator *BinaryOperator::CreateNSWNeg(Value *Op, const Twine &Name,
BasicBlock *InsertAtEnd) {
Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
return BinaryOperator::CreateNSWSub(zero, Op, Name, InsertAtEnd);
}
BinaryOperator *BinaryOperator::CreateNUWNeg(Value *Op, const Twine &Name,
Instruction *InsertBefore) {
Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
return BinaryOperator::CreateNUWSub(zero, Op, Name, InsertBefore);
}
BinaryOperator *BinaryOperator::CreateNUWNeg(Value *Op, const Twine &Name,
BasicBlock *InsertAtEnd) {
Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
return BinaryOperator::CreateNUWSub(zero, Op, Name, InsertAtEnd);
}
BinaryOperator *BinaryOperator::CreateFNeg(Value *Op, const Twine &Name,
Instruction *InsertBefore) {
Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
return new BinaryOperator(Instruction::FSub, zero, Op,
Op->getType(), Name, InsertBefore);
}
BinaryOperator *BinaryOperator::CreateFNeg(Value *Op, const Twine &Name,
BasicBlock *InsertAtEnd) {
Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
return new BinaryOperator(Instruction::FSub, zero, Op,
Op->getType(), Name, InsertAtEnd);
}
BinaryOperator *BinaryOperator::CreateNot(Value *Op, const Twine &Name,
Instruction *InsertBefore) {
Constant *C = Constant::getAllOnesValue(Op->getType());
return new BinaryOperator(Instruction::Xor, Op, C,
Op->getType(), Name, InsertBefore);
}
BinaryOperator *BinaryOperator::CreateNot(Value *Op, const Twine &Name,
BasicBlock *InsertAtEnd) {
Constant *AllOnes = Constant::getAllOnesValue(Op->getType());
return new BinaryOperator(Instruction::Xor, Op, AllOnes,
Op->getType(), Name, InsertAtEnd);
}
// isConstantAllOnes - Helper function for several functions below
static inline bool isConstantAllOnes(const Value *V) {
if (const Constant *C = dyn_cast<Constant>(V))
return C->isAllOnesValue();
return false;
}
bool BinaryOperator::isNeg(const Value *V) {
if (const BinaryOperator *Bop = dyn_cast<BinaryOperator>(V))
if (Bop->getOpcode() == Instruction::Sub)
if (Constant* C = dyn_cast<Constant>(Bop->getOperand(0)))
return C->isNegativeZeroValue();
return false;
}
bool BinaryOperator::isFNeg(const Value *V, bool IgnoreZeroSign) {
if (const BinaryOperator *Bop = dyn_cast<BinaryOperator>(V))
if (Bop->getOpcode() == Instruction::FSub)
if (Constant* C = dyn_cast<Constant>(Bop->getOperand(0))) {
if (!IgnoreZeroSign)
IgnoreZeroSign = cast<Instruction>(V)->hasNoSignedZeros();
return !IgnoreZeroSign ? C->isNegativeZeroValue() : C->isZeroValue();
}
return false;
}
bool BinaryOperator::isNot(const Value *V) {
if (const BinaryOperator *Bop = dyn_cast<BinaryOperator>(V))
return (Bop->getOpcode() == Instruction::Xor &&
(isConstantAllOnes(Bop->getOperand(1)) ||
isConstantAllOnes(Bop->getOperand(0))));
return false;
}
Value *BinaryOperator::getNegArgument(Value *BinOp) {
return cast<BinaryOperator>(BinOp)->getOperand(1);
}
const Value *BinaryOperator::getNegArgument(const Value *BinOp) {
return getNegArgument(const_cast<Value*>(BinOp));
}
Value *BinaryOperator::getFNegArgument(Value *BinOp) {
return cast<BinaryOperator>(BinOp)->getOperand(1);
}
const Value *BinaryOperator::getFNegArgument(const Value *BinOp) {
return getFNegArgument(const_cast<Value*>(BinOp));
}
Value *BinaryOperator::getNotArgument(Value *BinOp) {
assert(isNot(BinOp) && "getNotArgument on non-'not' instruction!");
BinaryOperator *BO = cast<BinaryOperator>(BinOp);
Value *Op0 = BO->getOperand(0);
Value *Op1 = BO->getOperand(1);
if (isConstantAllOnes(Op0)) return Op1;
assert(isConstantAllOnes(Op1));
return Op0;
}
const Value *BinaryOperator::getNotArgument(const Value *BinOp) {
return getNotArgument(const_cast<Value*>(BinOp));
}
// swapOperands - Exchange the two operands to this instruction. This
// instruction is safe to use on any binary instruction and does not
// modify the semantics of the instruction. If the instruction is
// order dependent (SetLT f.e.) the opcode is changed.
//
bool BinaryOperator::swapOperands() {
if (!isCommutative())
return true; // Can't commute operands
Op<0>().swap(Op<1>());
return false;
}
void BinaryOperator::setHasNoUnsignedWrap(bool b) {
cast<OverflowingBinaryOperator>(this)->setHasNoUnsignedWrap(b);
}
void BinaryOperator::setHasNoSignedWrap(bool b) {
cast<OverflowingBinaryOperator>(this)->setHasNoSignedWrap(b);
}
void BinaryOperator::setIsExact(bool b) {
cast<PossiblyExactOperator>(this)->setIsExact(b);
}
bool BinaryOperator::hasNoUnsignedWrap() const {
return cast<OverflowingBinaryOperator>(this)->hasNoUnsignedWrap();
}
bool BinaryOperator::hasNoSignedWrap() const {
return cast<OverflowingBinaryOperator>(this)->hasNoSignedWrap();
}
bool BinaryOperator::isExact() const {
return cast<PossiblyExactOperator>(this)->isExact();
}
void BinaryOperator::copyIRFlags(const Value *V) {
// Copy the wrapping flags.
if (auto *OB = dyn_cast<OverflowingBinaryOperator>(V)) {
setHasNoSignedWrap(OB->hasNoSignedWrap());
setHasNoUnsignedWrap(OB->hasNoUnsignedWrap());
}
// Copy the exact flag.
if (auto *PE = dyn_cast<PossiblyExactOperator>(V))
setIsExact(PE->isExact());
// Copy the fast-math flags.
if (auto *FP = dyn_cast<FPMathOperator>(V))
copyFastMathFlags(FP->getFastMathFlags());
}
void BinaryOperator::andIRFlags(const Value *V) {
if (auto *OB = dyn_cast<OverflowingBinaryOperator>(V)) {
setHasNoSignedWrap(hasNoSignedWrap() && OB->hasNoSignedWrap());
setHasNoUnsignedWrap(hasNoUnsignedWrap() && OB->hasNoUnsignedWrap());
}
if (auto *PE = dyn_cast<PossiblyExactOperator>(V))
setIsExact(isExact() && PE->isExact());
if (auto *FP = dyn_cast<FPMathOperator>(V)) {
FastMathFlags FM = getFastMathFlags();
FM &= FP->getFastMathFlags();
copyFastMathFlags(FM);
}
}
//===----------------------------------------------------------------------===//
// FPMathOperator Class
//===----------------------------------------------------------------------===//
/// getFPAccuracy - Get the maximum error permitted by this operation in ULPs.
/// An accuracy of 0.0 means that the operation should be performed with the
/// default precision.
float FPMathOperator::getFPAccuracy() const {
const MDNode *MD =
cast<Instruction>(this)->getMetadata(LLVMContext::MD_fpmath);
if (!MD)
return 0.0;
ConstantFP *Accuracy = mdconst::extract<ConstantFP>(MD->getOperand(0));
return Accuracy->getValueAPF().convertToFloat();
}
//===----------------------------------------------------------------------===//
// CastInst Class
//===----------------------------------------------------------------------===//
void CastInst::anchor() {}
// Just determine if this cast only deals with integral->integral conversion.
bool CastInst::isIntegerCast() const {
switch (getOpcode()) {
default: return false;
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::Trunc:
return true;
case Instruction::BitCast:
return getOperand(0)->getType()->isIntegerTy() &&
getType()->isIntegerTy();
}
}
bool CastInst::isLosslessCast() const {
// Only BitCast can be lossless, exit fast if we're not BitCast
if (getOpcode() != Instruction::BitCast)
return false;
// Identity cast is always lossless
Type* SrcTy = getOperand(0)->getType();
Type* DstTy = getType();
if (SrcTy == DstTy)
return true;
// Pointer to pointer is always lossless.
if (SrcTy->isPointerTy())
return DstTy->isPointerTy();
return false; // Other types have no identity values
}
/// This function determines if the CastInst does not require any bits to be
/// changed in order to effect the cast. Essentially, it identifies cases where
/// no code gen is necessary for the cast, hence the name no-op cast. For
/// example, the following are all no-op casts:
/// # bitcast i32* %x to i8*
/// # bitcast <2 x i32> %x to <4 x i16>
/// # ptrtoint i32* %x to i32 ; on 32-bit plaforms only
/// @brief Determine if the described cast is a no-op.
bool CastInst::isNoopCast(Instruction::CastOps Opcode,
Type *SrcTy,
Type *DestTy,
Type *IntPtrTy) {
switch (Opcode) {
default: llvm_unreachable("Invalid CastOp");
case Instruction::Trunc:
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::FPTrunc:
case Instruction::FPExt:
case Instruction::UIToFP:
case Instruction::SIToFP:
case Instruction::FPToUI:
case Instruction::FPToSI:
case Instruction::AddrSpaceCast:
// TODO: Target informations may give a more accurate answer here.
return false;
case Instruction::BitCast:
return true; // BitCast never modifies bits.
case Instruction::PtrToInt:
return IntPtrTy->getScalarSizeInBits() ==
DestTy->getScalarSizeInBits();
case Instruction::IntToPtr:
return IntPtrTy->getScalarSizeInBits() ==
SrcTy->getScalarSizeInBits();
}
}
/// @brief Determine if a cast is a no-op.
bool CastInst::isNoopCast(Type *IntPtrTy) const {
return isNoopCast(getOpcode(), getOperand(0)->getType(), getType(), IntPtrTy);
}
bool CastInst::isNoopCast(const DataLayout &DL) const {
Type *PtrOpTy = nullptr;
if (getOpcode() == Instruction::PtrToInt)
PtrOpTy = getOperand(0)->getType();
else if (getOpcode() == Instruction::IntToPtr)
PtrOpTy = getType();
Type *IntPtrTy =
PtrOpTy ? DL.getIntPtrType(PtrOpTy) : DL.getIntPtrType(getContext(), 0);
return isNoopCast(getOpcode(), getOperand(0)->getType(), getType(), IntPtrTy);
}
/// This function determines if a pair of casts can be eliminated and what
/// opcode should be used in the elimination. This assumes that there are two
/// instructions like this:
/// * %F = firstOpcode SrcTy %x to MidTy
/// * %S = secondOpcode MidTy %F to DstTy
/// The function returns a resultOpcode so these two casts can be replaced with:
/// * %Replacement = resultOpcode %SrcTy %x to DstTy
/// If no such cast is permited, the function returns 0.
unsigned CastInst::isEliminableCastPair(
Instruction::CastOps firstOp, Instruction::CastOps secondOp,
Type *SrcTy, Type *MidTy, Type *DstTy, Type *SrcIntPtrTy, Type *MidIntPtrTy,
Type *DstIntPtrTy) {
// Define the 144 possibilities for these two cast instructions. The values
// in this matrix determine what to do in a given situation and select the
// case in the switch below. The rows correspond to firstOp, the columns
// correspond to secondOp. In looking at the table below, keep in mind
// the following cast properties:
//
// Size Compare Source Destination
// Operator Src ? Size Type Sign Type Sign
// -------- ------------ ------------------- ---------------------
// TRUNC > Integer Any Integral Any
// ZEXT < Integral Unsigned Integer Any
// SEXT < Integral Signed Integer Any
// FPTOUI n/a FloatPt n/a Integral Unsigned
// FPTOSI n/a FloatPt n/a Integral Signed
// UITOFP n/a Integral Unsigned FloatPt n/a
// SITOFP n/a Integral Signed FloatPt n/a
// FPTRUNC > FloatPt n/a FloatPt n/a
// FPEXT < FloatPt n/a FloatPt n/a
// PTRTOINT n/a Pointer n/a Integral Unsigned
// INTTOPTR n/a Integral Unsigned Pointer n/a
// BITCAST = FirstClass n/a FirstClass n/a
// ADDRSPCST n/a Pointer n/a Pointer n/a
//
// NOTE: some transforms are safe, but we consider them to be non-profitable.
// For example, we could merge "fptoui double to i32" + "zext i32 to i64",
// into "fptoui double to i64", but this loses information about the range
// of the produced value (we no longer know the top-part is all zeros).
// Further this conversion is often much more expensive for typical hardware,
// and causes issues when building libgcc. We disallow fptosi+sext for the
// same reason.
const unsigned numCastOps =
Instruction::CastOpsEnd - Instruction::CastOpsBegin;
static const uint8_t CastResults[numCastOps][numCastOps] = {
// T F F U S F F P I B A -+
// R Z S P P I I T P 2 N T S |
// U E E 2 2 2 2 R E I T C C +- secondOp
// N X X U S F F N X N 2 V V |
// C T T I I P P C T T P T T -+
{ 1, 0, 0,99,99, 0, 0,99,99,99, 0, 3, 0}, // Trunc -+
{ 8, 1, 9,99,99, 2,17,99,99,99, 2, 3, 0}, // ZExt |
{ 8, 0, 1,99,99, 0, 2,99,99,99, 0, 3, 0}, // SExt |
{ 0, 0, 0,99,99, 0, 0,99,99,99, 0, 3, 0}, // FPToUI |
{ 0, 0, 0,99,99, 0, 0,99,99,99, 0, 3, 0}, // FPToSI |
{ 99,99,99, 0, 0,99,99, 0, 0,99,99, 4, 0}, // UIToFP +- firstOp
{ 99,99,99, 0, 0,99,99, 0, 0,99,99, 4, 0}, // SIToFP |
{ 99,99,99, 0, 0,99,99, 0, 0,99,99, 4, 0}, // FPTrunc |
{ 99,99,99, 2, 2,99,99,10, 2,99,99, 4, 0}, // FPExt |
{ 1, 0, 0,99,99, 0, 0,99,99,99, 7, 3, 0}, // PtrToInt |
{ 99,99,99,99,99,99,99,99,99,11,99,15, 0}, // IntToPtr |
{ 5, 5, 5, 6, 6, 5, 5, 6, 6,16, 5, 1,14}, // BitCast |
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,13,12}, // AddrSpaceCast -+
};
// If either of the casts are a bitcast from scalar to vector, disallow the
// merging. However, bitcast of A->B->A are allowed.
bool isFirstBitcast = (firstOp == Instruction::BitCast);
bool isSecondBitcast = (secondOp == Instruction::BitCast);
bool chainedBitcast = (SrcTy == DstTy && isFirstBitcast && isSecondBitcast);
// Check if any of the bitcasts convert scalars<->vectors.
if ((isFirstBitcast && isa<VectorType>(SrcTy) != isa<VectorType>(MidTy)) ||
(isSecondBitcast && isa<VectorType>(MidTy) != isa<VectorType>(DstTy)))
// Unless we are bitcasing to the original type, disallow optimizations.
if (!chainedBitcast) return 0;
int ElimCase = CastResults[firstOp-Instruction::CastOpsBegin]
[secondOp-Instruction::CastOpsBegin];
switch (ElimCase) {
case 0:
// Categorically disallowed.
return 0;
case 1:
// Allowed, use first cast's opcode.
return firstOp;
case 2:
// Allowed, use second cast's opcode.
return secondOp;
case 3:
// No-op cast in second op implies firstOp as long as the DestTy
// is integer and we are not converting between a vector and a
// non-vector type.
if (!SrcTy->isVectorTy() && DstTy->isIntegerTy())
return firstOp;
return 0;
case 4:
// No-op cast in second op implies firstOp as long as the DestTy
// is floating point.
if (DstTy->isFloatingPointTy())
return firstOp;
return 0;
case 5:
// No-op cast in first op implies secondOp as long as the SrcTy
// is an integer.
if (SrcTy->isIntegerTy())
return secondOp;
return 0;
case 6:
// No-op cast in first op implies secondOp as long as the SrcTy
// is a floating point.
if (SrcTy->isFloatingPointTy())
return secondOp;
return 0;
case 7: {
// Cannot simplify if address spaces are different!
if (SrcTy->getPointerAddressSpace() != DstTy->getPointerAddressSpace())
return 0;
unsigned MidSize = MidTy->getScalarSizeInBits();
// We can still fold this without knowing the actual sizes as long we
// know that the intermediate pointer is the largest possible
// pointer size.
// FIXME: Is this always true?
if (MidSize == 64)
return Instruction::BitCast;
// ptrtoint, inttoptr -> bitcast (ptr -> ptr) if int size is >= ptr size.
if (!SrcIntPtrTy || DstIntPtrTy != SrcIntPtrTy)
return 0;
unsigned PtrSize = SrcIntPtrTy->getScalarSizeInBits();
if (MidSize >= PtrSize)
return Instruction::BitCast;
return 0;
}
case 8: {
// ext, trunc -> bitcast, if the SrcTy and DstTy are same size
// ext, trunc -> ext, if sizeof(SrcTy) < sizeof(DstTy)
// ext, trunc -> trunc, if sizeof(SrcTy) > sizeof(DstTy)
unsigned SrcSize = SrcTy->getScalarSizeInBits();
unsigned DstSize = DstTy->getScalarSizeInBits();
if (SrcSize == DstSize)
return Instruction::BitCast;
else if (SrcSize < DstSize)
return firstOp;
return secondOp;
}
case 9:
// zext, sext -> zext, because sext can't sign extend after zext
return Instruction::ZExt;
case 10:
// fpext followed by ftrunc is allowed if the bit size returned to is
// the same as the original, in which case its just a bitcast
if (SrcTy == DstTy)
return Instruction::BitCast;
return 0; // If the types are not the same we can't eliminate it.
case 11: {
// inttoptr, ptrtoint -> bitcast if SrcSize<=PtrSize and SrcSize==DstSize
if (!MidIntPtrTy)
return 0;
unsigned PtrSize = MidIntPtrTy->getScalarSizeInBits();
unsigned SrcSize = SrcTy->getScalarSizeInBits();
unsigned DstSize = DstTy->getScalarSizeInBits();
if (SrcSize <= PtrSize && SrcSize == DstSize)
return Instruction::BitCast;
return 0;
}
case 12: {
// addrspacecast, addrspacecast -> bitcast, if SrcAS == DstAS
// addrspacecast, addrspacecast -> addrspacecast, if SrcAS != DstAS
if (SrcTy->getPointerAddressSpace() != DstTy->getPointerAddressSpace())
return Instruction::AddrSpaceCast;
return Instruction::BitCast;
}
case 13:
// FIXME: this state can be merged with (1), but the following assert
// is useful to check the correcteness of the sequence due to semantic
// change of bitcast.
assert(
SrcTy->isPtrOrPtrVectorTy() &&
MidTy->isPtrOrPtrVectorTy() &&
DstTy->isPtrOrPtrVectorTy() &&
SrcTy->getPointerAddressSpace() != MidTy->getPointerAddressSpace() &&
MidTy->getPointerAddressSpace() == DstTy->getPointerAddressSpace() &&
"Illegal addrspacecast, bitcast sequence!");
// Allowed, use first cast's opcode
return firstOp;
case 14:
// bitcast, addrspacecast -> addrspacecast if the element type of
// bitcast's source is the same as that of addrspacecast's destination.
if (SrcTy->getPointerElementType() == DstTy->getPointerElementType())
return Instruction::AddrSpaceCast;
return 0;
case 15:
// FIXME: this state can be merged with (1), but the following assert
// is useful to check the correcteness of the sequence due to semantic
// change of bitcast.
assert(
SrcTy->isIntOrIntVectorTy() &&
MidTy->isPtrOrPtrVectorTy() &&
DstTy->isPtrOrPtrVectorTy() &&
MidTy->getPointerAddressSpace() == DstTy->getPointerAddressSpace() &&
"Illegal inttoptr, bitcast sequence!");
// Allowed, use first cast's opcode
return firstOp;
case 16:
// FIXME: this state can be merged with (2), but the following assert
// is useful to check the correcteness of the sequence due to semantic
// change of bitcast.
assert(
SrcTy->isPtrOrPtrVectorTy() &&
MidTy->isPtrOrPtrVectorTy() &&
DstTy->isIntOrIntVectorTy() &&
SrcTy->getPointerAddressSpace() == MidTy->getPointerAddressSpace() &&
"Illegal bitcast, ptrtoint sequence!");
// Allowed, use second cast's opcode
return secondOp;
case 17:
// (sitofp (zext x)) -> (uitofp x)
return Instruction::UIToFP;
case 99:
// Cast combination can't happen (error in input). This is for all cases
// where the MidTy is not the same for the two cast instructions.
llvm_unreachable("Invalid Cast Combination");
default:
llvm_unreachable("Error in CastResults table!!!");
}
}
CastInst *CastInst::Create(Instruction::CastOps op, Value *S, Type *Ty,
const Twine &Name, Instruction *InsertBefore) {
assert(castIsValid(op, S, Ty) && "Invalid cast!");
// Construct and return the appropriate CastInst subclass
switch (op) {
case Trunc: return new TruncInst (S, Ty, Name, InsertBefore);
case ZExt: return new ZExtInst (S, Ty, Name, InsertBefore);
case SExt: return new SExtInst (S, Ty, Name, InsertBefore);
case FPTrunc: return new FPTruncInst (S, Ty, Name, InsertBefore);
case FPExt: return new FPExtInst (S, Ty, Name, InsertBefore);
case UIToFP: return new UIToFPInst (S, Ty, Name, InsertBefore);
case SIToFP: return new SIToFPInst (S, Ty, Name, InsertBefore);
case FPToUI: return new FPToUIInst (S, Ty, Name, InsertBefore);
case FPToSI: return new FPToSIInst (S, Ty, Name, InsertBefore);
case PtrToInt: return new PtrToIntInst (S, Ty, Name, InsertBefore);
case IntToPtr: return new IntToPtrInst (S, Ty, Name, InsertBefore);
case BitCast: return new BitCastInst (S, Ty, Name, InsertBefore);
case AddrSpaceCast: return new AddrSpaceCastInst (S, Ty, Name, InsertBefore);
default: llvm_unreachable("Invalid opcode provided");
}
}
CastInst *CastInst::Create(Instruction::CastOps op, Value *S, Type *Ty,
const Twine &Name, BasicBlock *InsertAtEnd) {
assert(castIsValid(op, S, Ty) && "Invalid cast!");
// Construct and return the appropriate CastInst subclass
switch (op) {
case Trunc: return new TruncInst (S, Ty, Name, InsertAtEnd);
case ZExt: return new ZExtInst (S, Ty, Name, InsertAtEnd);
case SExt: return new SExtInst (S, Ty, Name, InsertAtEnd);
case FPTrunc: return new FPTruncInst (S, Ty, Name, InsertAtEnd);
case FPExt: return new FPExtInst (S, Ty, Name, InsertAtEnd);
case UIToFP: return new UIToFPInst (S, Ty, Name, InsertAtEnd);
case SIToFP: return new SIToFPInst (S, Ty, Name, InsertAtEnd);
case FPToUI: return new FPToUIInst (S, Ty, Name, InsertAtEnd);
case FPToSI: return new FPToSIInst (S, Ty, Name, InsertAtEnd);
case PtrToInt: return new PtrToIntInst (S, Ty, Name, InsertAtEnd);
case IntToPtr: return new IntToPtrInst (S, Ty, Name, InsertAtEnd);
case BitCast: return new BitCastInst (S, Ty, Name, InsertAtEnd);
case AddrSpaceCast: return new AddrSpaceCastInst (S, Ty, Name, InsertAtEnd);
default: llvm_unreachable("Invalid opcode provided");
}
}
CastInst *CastInst::CreateZExtOrBitCast(Value *S, Type *Ty,
const Twine &Name,
Instruction *InsertBefore) {
if (S->getType()->getScalarSizeInBits() == Ty->getScalarSizeInBits())
return Create(Instruction::BitCast, S, Ty, Name, InsertBefore);
return Create(Instruction::ZExt, S, Ty, Name, InsertBefore);
}
CastInst *CastInst::CreateZExtOrBitCast(Value *S, Type *Ty,
const Twine &Name,
BasicBlock *InsertAtEnd) {
if (S->getType()->getScalarSizeInBits() == Ty->getScalarSizeInBits())
return Create(Instruction::BitCast, S, Ty, Name, InsertAtEnd);
return Create(Instruction::ZExt, S, Ty, Name, InsertAtEnd);
}
CastInst *CastInst::CreateSExtOrBitCast(Value *S, Type *Ty,
const Twine &Name,
Instruction *InsertBefore) {
if (S->getType()->getScalarSizeInBits() == Ty->getScalarSizeInBits())
return Create(Instruction::BitCast, S, Ty, Name, InsertBefore);
return Create(Instruction::SExt, S, Ty, Name, InsertBefore);
}
CastInst *CastInst::CreateSExtOrBitCast(Value *S, Type *Ty,
const Twine &Name,
BasicBlock *InsertAtEnd) {
if (S->getType()->getScalarSizeInBits() == Ty->getScalarSizeInBits())
return Create(Instruction::BitCast, S, Ty, Name, InsertAtEnd);
return Create(Instruction::SExt, S, Ty, Name, InsertAtEnd);
}
CastInst *CastInst::CreateTruncOrBitCast(Value *S, Type *Ty,
const Twine &Name,
Instruction *InsertBefore) {
if (S->getType()->getScalarSizeInBits() == Ty->getScalarSizeInBits())
return Create(Instruction::BitCast, S, Ty, Name, InsertBefore);
return Create(Instruction::Trunc, S, Ty, Name, InsertBefore);
}
CastInst *CastInst::CreateTruncOrBitCast(Value *S, Type *Ty,
const Twine &Name,
BasicBlock *InsertAtEnd) {
if (S->getType()->getScalarSizeInBits() == Ty->getScalarSizeInBits())
return Create(Instruction::BitCast, S, Ty, Name, InsertAtEnd);
return Create(Instruction::Trunc, S, Ty, Name, InsertAtEnd);
}
CastInst *CastInst::CreatePointerCast(Value *S, Type *Ty,
const Twine &Name,
BasicBlock *InsertAtEnd) {
assert(S->getType()->isPtrOrPtrVectorTy() && "Invalid cast");
assert((Ty->isIntOrIntVectorTy() || Ty->isPtrOrPtrVectorTy()) &&
"Invalid cast");
assert(Ty->isVectorTy() == S->getType()->isVectorTy() && "Invalid cast");
assert((!Ty->isVectorTy() ||
Ty->getVectorNumElements() == S->getType()->getVectorNumElements()) &&
"Invalid cast");
if (Ty->isIntOrIntVectorTy())
return Create(Instruction::PtrToInt, S, Ty, Name, InsertAtEnd);
return CreatePointerBitCastOrAddrSpaceCast(S, Ty, Name, InsertAtEnd);
}
/// @brief Create a BitCast or a PtrToInt cast instruction
CastInst *CastInst::CreatePointerCast(Value *S, Type *Ty,
const Twine &Name,
Instruction *InsertBefore) {
assert(S->getType()->isPtrOrPtrVectorTy() && "Invalid cast");
assert((Ty->isIntOrIntVectorTy() || Ty->isPtrOrPtrVectorTy()) &&
"Invalid cast");
assert(Ty->isVectorTy() == S->getType()->isVectorTy() && "Invalid cast");
assert((!Ty->isVectorTy() ||
Ty->getVectorNumElements() == S->getType()->getVectorNumElements()) &&
"Invalid cast");
if (Ty->isIntOrIntVectorTy())
return Create(Instruction::PtrToInt, S, Ty, Name, InsertBefore);
return CreatePointerBitCastOrAddrSpaceCast(S, Ty, Name, InsertBefore);
}
CastInst *CastInst::CreatePointerBitCastOrAddrSpaceCast(
Value *S, Type *Ty,
const Twine &Name,
BasicBlock *InsertAtEnd) {
assert(S->getType()->isPtrOrPtrVectorTy() && "Invalid cast");
assert(Ty->isPtrOrPtrVectorTy() && "Invalid cast");
if (S->getType()->getPointerAddressSpace() != Ty->getPointerAddressSpace())
return Create(Instruction::AddrSpaceCast, S, Ty, Name, InsertAtEnd);
return Create(Instruction::BitCast, S, Ty, Name, InsertAtEnd);
}
CastInst *CastInst::CreatePointerBitCastOrAddrSpaceCast(
Value *S, Type *Ty,
const Twine &Name,
Instruction *InsertBefore) {
assert(S->getType()->isPtrOrPtrVectorTy() && "Invalid cast");
assert(Ty->isPtrOrPtrVectorTy() && "Invalid cast");
if (S->getType()->getPointerAddressSpace() != Ty->getPointerAddressSpace())
return Create(Instruction::AddrSpaceCast, S, Ty, Name, InsertBefore);
return Create(Instruction::BitCast, S, Ty, Name, InsertBefore);
}
CastInst *CastInst::CreateBitOrPointerCast(Value *S, Type *Ty,
const Twine &Name,
Instruction *InsertBefore) {
if (S->getType()->isPointerTy() && Ty->isIntegerTy())
return Create(Instruction::PtrToInt, S, Ty, Name, InsertBefore);
if (S->getType()->isIntegerTy() && Ty->isPointerTy())
return Create(Instruction::IntToPtr, S, Ty, Name, InsertBefore);
return Create(Instruction::BitCast, S, Ty, Name, InsertBefore);
}
CastInst *CastInst::CreateIntegerCast(Value *C, Type *Ty,
bool isSigned, const Twine &Name,
Instruction *InsertBefore) {
assert(C->getType()->isIntOrIntVectorTy() && Ty->isIntOrIntVectorTy() &&
"Invalid integer cast");
unsigned SrcBits = C->getType()->getScalarSizeInBits();
unsigned DstBits = Ty->getScalarSizeInBits();
Instruction::CastOps opcode =
(SrcBits == DstBits ? Instruction::BitCast :
(SrcBits > DstBits ? Instruction::Trunc :
(isSigned ? Instruction::SExt : Instruction::ZExt)));
return Create(opcode, C, Ty, Name, InsertBefore);
}
CastInst *CastInst::CreateIntegerCast(Value *C, Type *Ty,
bool isSigned, const Twine &Name,
BasicBlock *InsertAtEnd) {
assert(C->getType()->isIntOrIntVectorTy() && Ty->isIntOrIntVectorTy() &&
"Invalid cast");
unsigned SrcBits = C->getType()->getScalarSizeInBits();
unsigned DstBits = Ty->getScalarSizeInBits();
Instruction::CastOps opcode =
(SrcBits == DstBits ? Instruction::BitCast :
(SrcBits > DstBits ? Instruction::Trunc :
(isSigned ? Instruction::SExt : Instruction::ZExt)));
return Create(opcode, C, Ty, Name, InsertAtEnd);
}
CastInst *CastInst::CreateFPCast(Value *C, Type *Ty,
const Twine &Name,
Instruction *InsertBefore) {
assert(C->getType()->isFPOrFPVectorTy() && Ty->isFPOrFPVectorTy() &&
"Invalid cast");
unsigned SrcBits = C->getType()->getScalarSizeInBits();
unsigned DstBits = Ty->getScalarSizeInBits();
Instruction::CastOps opcode =
(SrcBits == DstBits ? Instruction::BitCast :
(SrcBits > DstBits ? Instruction::FPTrunc : Instruction::FPExt));
return Create(opcode, C, Ty, Name, InsertBefore);
}
CastInst *CastInst::CreateFPCast(Value *C, Type *Ty,
const Twine &Name,
BasicBlock *InsertAtEnd) {
assert(C->getType()->isFPOrFPVectorTy() && Ty->isFPOrFPVectorTy() &&
"Invalid cast");
unsigned SrcBits = C->getType()->getScalarSizeInBits();
unsigned DstBits = Ty->getScalarSizeInBits();
Instruction::CastOps opcode =
(SrcBits == DstBits ? Instruction::BitCast :
(SrcBits > DstBits ? Instruction::FPTrunc : Instruction::FPExt));
return Create(opcode, C, Ty, Name, InsertAtEnd);
}
// Check whether it is valid to call getCastOpcode for these types.
// This routine must be kept in sync with getCastOpcode.
bool CastInst::isCastable(Type *SrcTy, Type *DestTy) {
if (!SrcTy->isFirstClassType() || !DestTy->isFirstClassType())
return false;
if (SrcTy == DestTy)
return true;
if (VectorType *SrcVecTy = dyn_cast<VectorType>(SrcTy))
if (VectorType *DestVecTy = dyn_cast<VectorType>(DestTy))
if (SrcVecTy->getNumElements() == DestVecTy->getNumElements()) {
// An element by element cast. Valid if casting the elements is valid.
SrcTy = SrcVecTy->getElementType();
DestTy = DestVecTy->getElementType();
}
// Get the bit sizes, we'll need these
unsigned SrcBits = SrcTy->getPrimitiveSizeInBits(); // 0 for ptr
unsigned DestBits = DestTy->getPrimitiveSizeInBits(); // 0 for ptr
// Run through the possibilities ...
if (DestTy->isIntegerTy()) { // Casting to integral
if (SrcTy->isIntegerTy()) // Casting from integral
return true;
if (SrcTy->isFloatingPointTy()) // Casting from floating pt
return true;
if (SrcTy->isVectorTy()) // Casting from vector
return DestBits == SrcBits;
// Casting from something else
return SrcTy->isPointerTy();
}
if (DestTy->isFloatingPointTy()) { // Casting to floating pt
if (SrcTy->isIntegerTy()) // Casting from integral
return true;
if (SrcTy->isFloatingPointTy()) // Casting from floating pt
return true;
if (SrcTy->isVectorTy()) // Casting from vector
return DestBits == SrcBits;
// Casting from something else
return false;
}
if (DestTy->isVectorTy()) // Casting to vector
return DestBits == SrcBits;
if (DestTy->isPointerTy()) { // Casting to pointer
if (SrcTy->isPointerTy()) // Casting from pointer
return true;
return SrcTy->isIntegerTy(); // Casting from integral
}
if (DestTy->isX86_MMXTy()) {
if (SrcTy->isVectorTy())
return DestBits == SrcBits; // 64-bit vector to MMX
return false;
} // Casting to something else
return false;
}
bool CastInst::isBitCastable(Type *SrcTy, Type *DestTy) {
if (!SrcTy->isFirstClassType() || !DestTy->isFirstClassType())
return false;
if (SrcTy == DestTy)
return true;
if (VectorType *SrcVecTy = dyn_cast<VectorType>(SrcTy)) {
if (VectorType *DestVecTy = dyn_cast<VectorType>(DestTy)) {
if (SrcVecTy->getNumElements() == DestVecTy->getNumElements()) {
// An element by element cast. Valid if casting the elements is valid.
SrcTy = SrcVecTy->getElementType();
DestTy = DestVecTy->getElementType();
}
}
}
if (PointerType *DestPtrTy = dyn_cast<PointerType>(DestTy)) {
if (PointerType *SrcPtrTy = dyn_cast<PointerType>(SrcTy)) {
return SrcPtrTy->getAddressSpace() == DestPtrTy->getAddressSpace();
}
}
unsigned SrcBits = SrcTy->getPrimitiveSizeInBits(); // 0 for ptr
unsigned DestBits = DestTy->getPrimitiveSizeInBits(); // 0 for ptr
// Could still have vectors of pointers if the number of elements doesn't
// match
if (SrcBits == 0 || DestBits == 0)
return false;
if (SrcBits != DestBits)
return false;
if (DestTy->isX86_MMXTy() || SrcTy->isX86_MMXTy())
return false;
return true;
}
bool CastInst::isBitOrNoopPointerCastable(Type *SrcTy, Type *DestTy,
const DataLayout &DL) {
if (auto *PtrTy = dyn_cast<PointerType>(SrcTy))
if (auto *IntTy = dyn_cast<IntegerType>(DestTy))
return IntTy->getBitWidth() == DL.getPointerTypeSizeInBits(PtrTy);
if (auto *PtrTy = dyn_cast<PointerType>(DestTy))
if (auto *IntTy = dyn_cast<IntegerType>(SrcTy))
return IntTy->getBitWidth() == DL.getPointerTypeSizeInBits(PtrTy);
return isBitCastable(SrcTy, DestTy);
}
// Provide a way to get a "cast" where the cast opcode is inferred from the
// types and size of the operand. This, basically, is a parallel of the
// logic in the castIsValid function below. This axiom should hold:
// castIsValid( getCastOpcode(Val, Ty), Val, Ty)
// should not assert in castIsValid. In other words, this produces a "correct"
// casting opcode for the arguments passed to it.
// This routine must be kept in sync with isCastable.
Instruction::CastOps
CastInst::getCastOpcode(
const Value *Src, bool SrcIsSigned, Type *DestTy, bool DestIsSigned) {
Type *SrcTy = Src->getType();
assert(SrcTy->isFirstClassType() && DestTy->isFirstClassType() &&
"Only first class types are castable!");
if (SrcTy == DestTy)
return BitCast;
// FIXME: Check address space sizes here
if (VectorType *SrcVecTy = dyn_cast<VectorType>(SrcTy))
if (VectorType *DestVecTy = dyn_cast<VectorType>(DestTy))
if (SrcVecTy->getNumElements() == DestVecTy->getNumElements()) {
// An element by element cast. Find the appropriate opcode based on the
// element types.
SrcTy = SrcVecTy->getElementType();
DestTy = DestVecTy->getElementType();
}
// Get the bit sizes, we'll need these
unsigned SrcBits = SrcTy->getPrimitiveSizeInBits(); // 0 for ptr
unsigned DestBits = DestTy->getPrimitiveSizeInBits(); // 0 for ptr
// Run through the possibilities ...
if (DestTy->isIntegerTy()) { // Casting to integral
if (SrcTy->isIntegerTy()) { // Casting from integral
if (DestBits < SrcBits)
return Trunc; // int -> smaller int
else if (DestBits > SrcBits) { // its an extension
if (SrcIsSigned)
return SExt; // signed -> SEXT
else
return ZExt; // unsigned -> ZEXT
} else {
return BitCast; // Same size, No-op cast
}
} else if (SrcTy->isFloatingPointTy()) { // Casting from floating pt
if (DestIsSigned)
return FPToSI; // FP -> sint
else
return FPToUI; // FP -> uint
} else if (SrcTy->isVectorTy()) {
assert(DestBits == SrcBits &&
"Casting vector to integer of different width");
return BitCast; // Same size, no-op cast
} else {
assert(SrcTy->isPointerTy() &&
"Casting from a value that is not first-class type");
return PtrToInt; // ptr -> int
}
} else if (DestTy->isFloatingPointTy()) { // Casting to floating pt
if (SrcTy->isIntegerTy()) { // Casting from integral
if (SrcIsSigned)
return SIToFP; // sint -> FP
else
return UIToFP; // uint -> FP
} else if (SrcTy->isFloatingPointTy()) { // Casting from floating pt
if (DestBits < SrcBits) {
return FPTrunc; // FP -> smaller FP
} else if (DestBits > SrcBits) {
return FPExt; // FP -> larger FP
} else {
return BitCast; // same size, no-op cast
}
} else if (SrcTy->isVectorTy()) {
assert(DestBits == SrcBits &&
"Casting vector to floating point of different width");
return BitCast; // same size, no-op cast
}
llvm_unreachable("Casting pointer or non-first class to float");
} else if (DestTy->isVectorTy()) {
assert(DestBits == SrcBits &&
"Illegal cast to vector (wrong type or size)");
return BitCast;
} else if (DestTy->isPointerTy()) {
if (SrcTy->isPointerTy()) {
if (DestTy->getPointerAddressSpace() != SrcTy->getPointerAddressSpace())
return AddrSpaceCast;
return BitCast; // ptr -> ptr
} else if (SrcTy->isIntegerTy()) {
return IntToPtr; // int -> ptr
}
llvm_unreachable("Casting pointer to other than pointer or int");
} else if (DestTy->isX86_MMXTy()) {
if (SrcTy->isVectorTy()) {
assert(DestBits == SrcBits && "Casting vector of wrong width to X86_MMX");
return BitCast; // 64-bit vector to MMX
}
llvm_unreachable("Illegal cast to X86_MMX");
}
llvm_unreachable("Casting to type that is not first-class");
}
//===----------------------------------------------------------------------===//
// CastInst SubClass Constructors
//===----------------------------------------------------------------------===//
/// Check that the construction parameters for a CastInst are correct. This
/// could be broken out into the separate constructors but it is useful to have
/// it in one place and to eliminate the redundant code for getting the sizes
/// of the types involved.
bool
CastInst::castIsValid(Instruction::CastOps op, Value *S, Type *DstTy) {
// Check for type sanity on the arguments
Type *SrcTy = S->getType();
if (!SrcTy->isFirstClassType() || !DstTy->isFirstClassType() ||
SrcTy->isAggregateType() || DstTy->isAggregateType())
return false;
// Get the size of the types in bits, we'll need this later
unsigned SrcBitSize = SrcTy->getScalarSizeInBits();
unsigned DstBitSize = DstTy->getScalarSizeInBits();
// If these are vector types, get the lengths of the vectors (using zero for
// scalar types means that checking that vector lengths match also checks that
// scalars are not being converted to vectors or vectors to scalars).
unsigned SrcLength = SrcTy->isVectorTy() ?
cast<VectorType>(SrcTy)->getNumElements() : 0;
unsigned DstLength = DstTy->isVectorTy() ?
cast<VectorType>(DstTy)->getNumElements() : 0;
// Switch on the opcode provided
switch (op) {
default: return false; // This is an input error
case Instruction::Trunc:
return SrcTy->isIntOrIntVectorTy() && DstTy->isIntOrIntVectorTy() &&
SrcLength == DstLength && SrcBitSize > DstBitSize;
case Instruction::ZExt:
return SrcTy->isIntOrIntVectorTy() && DstTy->isIntOrIntVectorTy() &&
SrcLength == DstLength && SrcBitSize < DstBitSize;
case Instruction::SExt:
return SrcTy->isIntOrIntVectorTy() && DstTy->isIntOrIntVectorTy() &&
SrcLength == DstLength && SrcBitSize < DstBitSize;
case Instruction::FPTrunc:
return SrcTy->isFPOrFPVectorTy() && DstTy->isFPOrFPVectorTy() &&
SrcLength == DstLength && SrcBitSize > DstBitSize;
case Instruction::FPExt:
return SrcTy->isFPOrFPVectorTy() && DstTy->isFPOrFPVectorTy() &&
SrcLength == DstLength && SrcBitSize < DstBitSize;
case Instruction::UIToFP:
case Instruction::SIToFP:
return SrcTy->isIntOrIntVectorTy() && DstTy->isFPOrFPVectorTy() &&
SrcLength == DstLength;
case Instruction::FPToUI:
case Instruction::FPToSI:
return SrcTy->isFPOrFPVectorTy() && DstTy->isIntOrIntVectorTy() &&
SrcLength == DstLength;
case Instruction::PtrToInt:
if (isa<VectorType>(SrcTy) != isa<VectorType>(DstTy))
return false;
if (VectorType *VT = dyn_cast<VectorType>(SrcTy))
if (VT->getNumElements() != cast<VectorType>(DstTy)->getNumElements())
return false;
return SrcTy->getScalarType()->isPointerTy() &&
DstTy->getScalarType()->isIntegerTy();
case Instruction::IntToPtr:
if (isa<VectorType>(SrcTy) != isa<VectorType>(DstTy))
return false;
if (VectorType *VT = dyn_cast<VectorType>(SrcTy))
if (VT->getNumElements() != cast<VectorType>(DstTy)->getNumElements())
return false;
return SrcTy->getScalarType()->isIntegerTy() &&
DstTy->getScalarType()->isPointerTy();
case Instruction::BitCast: {
PointerType *SrcPtrTy = dyn_cast<PointerType>(SrcTy->getScalarType());
PointerType *DstPtrTy = dyn_cast<PointerType>(DstTy->getScalarType());
// BitCast implies a no-op cast of type only. No bits change.
// However, you can't cast pointers to anything but pointers.
if (!SrcPtrTy != !DstPtrTy)
return false;
// For non-pointer cases, the cast is okay if the source and destination bit
// widths are identical.
if (!SrcPtrTy)
return SrcTy->getPrimitiveSizeInBits() == DstTy->getPrimitiveSizeInBits();
// If both are pointers then the address spaces must match.
if (SrcPtrTy->getAddressSpace() != DstPtrTy->getAddressSpace())
return false;
// A vector of pointers must have the same number of elements.
if (VectorType *SrcVecTy = dyn_cast<VectorType>(SrcTy)) {
if (VectorType *DstVecTy = dyn_cast<VectorType>(DstTy))
return (SrcVecTy->getNumElements() == DstVecTy->getNumElements());
return false;
}
return true;
}
case Instruction::AddrSpaceCast: {
PointerType *SrcPtrTy = dyn_cast<PointerType>(SrcTy->getScalarType());
if (!SrcPtrTy)
return false;
PointerType *DstPtrTy = dyn_cast<PointerType>(DstTy->getScalarType());
if (!DstPtrTy)
return false;
if (SrcPtrTy->getAddressSpace() == DstPtrTy->getAddressSpace())
return false;
if (VectorType *SrcVecTy = dyn_cast<VectorType>(SrcTy)) {
if (VectorType *DstVecTy = dyn_cast<VectorType>(DstTy))
return (SrcVecTy->getNumElements() == DstVecTy->getNumElements());
return false;
}
return true;
}
}
}
TruncInst::TruncInst(
Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
) : CastInst(Ty, Trunc, S, Name, InsertBefore) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal Trunc");
}
TruncInst::TruncInst(
Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
) : CastInst(Ty, Trunc, S, Name, InsertAtEnd) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal Trunc");
}
ZExtInst::ZExtInst(
Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
) : CastInst(Ty, ZExt, S, Name, InsertBefore) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal ZExt");
}
ZExtInst::ZExtInst(
Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
) : CastInst(Ty, ZExt, S, Name, InsertAtEnd) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal ZExt");
}
SExtInst::SExtInst(
Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
) : CastInst(Ty, SExt, S, Name, InsertBefore) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal SExt");
}
SExtInst::SExtInst(
Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
) : CastInst(Ty, SExt, S, Name, InsertAtEnd) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal SExt");
}
FPTruncInst::FPTruncInst(
Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
) : CastInst(Ty, FPTrunc, S, Name, InsertBefore) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPTrunc");
}
FPTruncInst::FPTruncInst(
Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
) : CastInst(Ty, FPTrunc, S, Name, InsertAtEnd) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPTrunc");
}
FPExtInst::FPExtInst(
Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
) : CastInst(Ty, FPExt, S, Name, InsertBefore) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPExt");
}
FPExtInst::FPExtInst(
Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
) : CastInst(Ty, FPExt, S, Name, InsertAtEnd) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPExt");
}
UIToFPInst::UIToFPInst(
Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
) : CastInst(Ty, UIToFP, S, Name, InsertBefore) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal UIToFP");
}
UIToFPInst::UIToFPInst(
Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
) : CastInst(Ty, UIToFP, S, Name, InsertAtEnd) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal UIToFP");
}
SIToFPInst::SIToFPInst(
Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
) : CastInst(Ty, SIToFP, S, Name, InsertBefore) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal SIToFP");
}
SIToFPInst::SIToFPInst(
Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
) : CastInst(Ty, SIToFP, S, Name, InsertAtEnd) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal SIToFP");
}
FPToUIInst::FPToUIInst(
Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
) : CastInst(Ty, FPToUI, S, Name, InsertBefore) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPToUI");
}
FPToUIInst::FPToUIInst(
Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
) : CastInst(Ty, FPToUI, S, Name, InsertAtEnd) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPToUI");
}
FPToSIInst::FPToSIInst(
Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
) : CastInst(Ty, FPToSI, S, Name, InsertBefore) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPToSI");
}
FPToSIInst::FPToSIInst(
Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
) : CastInst(Ty, FPToSI, S, Name, InsertAtEnd) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPToSI");
}
PtrToIntInst::PtrToIntInst(
Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
) : CastInst(Ty, PtrToInt, S, Name, InsertBefore) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal PtrToInt");
}
PtrToIntInst::PtrToIntInst(
Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
) : CastInst(Ty, PtrToInt, S, Name, InsertAtEnd) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal PtrToInt");
}
IntToPtrInst::IntToPtrInst(
Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
) : CastInst(Ty, IntToPtr, S, Name, InsertBefore) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal IntToPtr");
}
IntToPtrInst::IntToPtrInst(
Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
) : CastInst(Ty, IntToPtr, S, Name, InsertAtEnd) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal IntToPtr");
}
BitCastInst::BitCastInst(
Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
) : CastInst(Ty, BitCast, S, Name, InsertBefore) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal BitCast");
}
BitCastInst::BitCastInst(
Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
) : CastInst(Ty, BitCast, S, Name, InsertAtEnd) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal BitCast");
}
AddrSpaceCastInst::AddrSpaceCastInst(
Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
) : CastInst(Ty, AddrSpaceCast, S, Name, InsertBefore) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal AddrSpaceCast");
}
AddrSpaceCastInst::AddrSpaceCastInst(
Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
) : CastInst(Ty, AddrSpaceCast, S, Name, InsertAtEnd) {
assert(castIsValid(getOpcode(), S, Ty) && "Illegal AddrSpaceCast");
}
//===----------------------------------------------------------------------===//
// CmpInst Classes
//===----------------------------------------------------------------------===//
void CmpInst::anchor() {}
CmpInst::CmpInst(Type *ty, OtherOps op, unsigned short predicate,
Value *LHS, Value *RHS, const Twine &Name,
Instruction *InsertBefore)
: Instruction(ty, op,
OperandTraits<CmpInst>::op_begin(this),
OperandTraits<CmpInst>::operands(this),
InsertBefore) {
Op<0>() = LHS;
Op<1>() = RHS;
setPredicate((Predicate)predicate);
setName(Name);
}
CmpInst::CmpInst(Type *ty, OtherOps op, unsigned short predicate,
Value *LHS, Value *RHS, const Twine &Name,
BasicBlock *InsertAtEnd)
: Instruction(ty, op,
OperandTraits<CmpInst>::op_begin(this),
OperandTraits<CmpInst>::operands(this),
InsertAtEnd) {
Op<0>() = LHS;
Op<1>() = RHS;
setPredicate((Predicate)predicate);
setName(Name);
}
CmpInst *
CmpInst::Create(OtherOps Op, unsigned short predicate,
Value *S1, Value *S2,
const Twine &Name, Instruction *InsertBefore) {
if (Op == Instruction::ICmp) {
if (InsertBefore)
return new ICmpInst(InsertBefore, CmpInst::Predicate(predicate),
S1, S2, Name);
else
return new ICmpInst(CmpInst::Predicate(predicate),
S1, S2, Name);
}
if (InsertBefore)
return new FCmpInst(InsertBefore, CmpInst::Predicate(predicate),
S1, S2, Name);
else
return new FCmpInst(CmpInst::Predicate(predicate),
S1, S2, Name);
}
CmpInst *
CmpInst::Create(OtherOps Op, unsigned short predicate, Value *S1, Value *S2,
const Twine &Name, BasicBlock *InsertAtEnd) {
if (Op == Instruction::ICmp) {
return new ICmpInst(*InsertAtEnd, CmpInst::Predicate(predicate),
S1, S2, Name);
}
return new FCmpInst(*InsertAtEnd, CmpInst::Predicate(predicate),
S1, S2, Name);
}
void CmpInst::swapOperands() {
if (ICmpInst *IC = dyn_cast<ICmpInst>(this))
IC->swapOperands();
else
cast<FCmpInst>(this)->swapOperands();
}
bool CmpInst::isCommutative() const {
if (const ICmpInst *IC = dyn_cast<ICmpInst>(this))
return IC->isCommutative();
return cast<FCmpInst>(this)->isCommutative();
}
bool CmpInst::isEquality() const {
if (const ICmpInst *IC = dyn_cast<ICmpInst>(this))
return IC->isEquality();
return cast<FCmpInst>(this)->isEquality();
}
CmpInst::Predicate CmpInst::getInversePredicate(Predicate pred) {
switch (pred) {
default: llvm_unreachable("Unknown cmp predicate!");
case ICMP_EQ: return ICMP_NE;
case ICMP_NE: return ICMP_EQ;
case ICMP_UGT: return ICMP_ULE;
case ICMP_ULT: return ICMP_UGE;
case ICMP_UGE: return ICMP_ULT;
case ICMP_ULE: return ICMP_UGT;
case ICMP_SGT: return ICMP_SLE;
case ICMP_SLT: return ICMP_SGE;
case ICMP_SGE: return ICMP_SLT;
case ICMP_SLE: return ICMP_SGT;
case FCMP_OEQ: return FCMP_UNE;
case FCMP_ONE: return FCMP_UEQ;
case FCMP_OGT: return FCMP_ULE;
case FCMP_OLT: return FCMP_UGE;
case FCMP_OGE: return FCMP_ULT;
case FCMP_OLE: return FCMP_UGT;
case FCMP_UEQ: return FCMP_ONE;
case FCMP_UNE: return FCMP_OEQ;
case FCMP_UGT: return FCMP_OLE;
case FCMP_ULT: return FCMP_OGE;
case FCMP_UGE: return FCMP_OLT;
case FCMP_ULE: return FCMP_OGT;
case FCMP_ORD: return FCMP_UNO;
case FCMP_UNO: return FCMP_ORD;
case FCMP_TRUE: return FCMP_FALSE;
case FCMP_FALSE: return FCMP_TRUE;
}
}
ICmpInst::Predicate ICmpInst::getSignedPredicate(Predicate pred) {
switch (pred) {
default: llvm_unreachable("Unknown icmp predicate!");
case ICMP_EQ: case ICMP_NE:
case ICMP_SGT: case ICMP_SLT: case ICMP_SGE: case ICMP_SLE:
return pred;
case ICMP_UGT: return ICMP_SGT;
case ICMP_ULT: return ICMP_SLT;
case ICMP_UGE: return ICMP_SGE;
case ICMP_ULE: return ICMP_SLE;
}
}
ICmpInst::Predicate ICmpInst::getUnsignedPredicate(Predicate pred) {
switch (pred) {
default: llvm_unreachable("Unknown icmp predicate!");
case ICMP_EQ: case ICMP_NE:
case ICMP_UGT: case ICMP_ULT: case ICMP_UGE: case ICMP_ULE:
return pred;
case ICMP_SGT: return ICMP_UGT;
case ICMP_SLT: return ICMP_ULT;
case ICMP_SGE: return ICMP_UGE;
case ICMP_SLE: return ICMP_ULE;
}
}
/// Initialize a set of values that all satisfy the condition with C.
///
ConstantRange
ICmpInst::makeConstantRange(Predicate pred, const APInt &C) {
APInt Lower(C);
APInt Upper(C);
uint32_t BitWidth = C.getBitWidth();
switch (pred) {
default: llvm_unreachable("Invalid ICmp opcode to ConstantRange ctor!");
case ICmpInst::ICMP_EQ: ++Upper; break;
case ICmpInst::ICMP_NE: ++Lower; break;
case ICmpInst::ICMP_ULT:
Lower = APInt::getMinValue(BitWidth);
// Check for an empty-set condition.
if (Lower == Upper)
return ConstantRange(BitWidth, /*isFullSet=*/false);
break;
case ICmpInst::ICMP_SLT:
Lower = APInt::getSignedMinValue(BitWidth);
// Check for an empty-set condition.
if (Lower == Upper)
return ConstantRange(BitWidth, /*isFullSet=*/false);
break;
case ICmpInst::ICMP_UGT:
++Lower; Upper = APInt::getMinValue(BitWidth); // Min = Next(Max)
// Check for an empty-set condition.
if (Lower == Upper)
return ConstantRange(BitWidth, /*isFullSet=*/false);
break;
case ICmpInst::ICMP_SGT:
++Lower; Upper = APInt::getSignedMinValue(BitWidth); // Min = Next(Max)
// Check for an empty-set condition.
if (Lower == Upper)
return ConstantRange(BitWidth, /*isFullSet=*/false);
break;
case ICmpInst::ICMP_ULE:
Lower = APInt::getMinValue(BitWidth); ++Upper;
// Check for a full-set condition.
if (Lower == Upper)
return ConstantRange(BitWidth, /*isFullSet=*/true);
break;
case ICmpInst::ICMP_SLE:
Lower = APInt::getSignedMinValue(BitWidth); ++Upper;
// Check for a full-set condition.
if (Lower == Upper)
return ConstantRange(BitWidth, /*isFullSet=*/true);
break;
case ICmpInst::ICMP_UGE:
Upper = APInt::getMinValue(BitWidth); // Min = Next(Max)
// Check for a full-set condition.
if (Lower == Upper)
return ConstantRange(BitWidth, /*isFullSet=*/true);
break;
case ICmpInst::ICMP_SGE:
Upper = APInt::getSignedMinValue(BitWidth); // Min = Next(Max)
// Check for a full-set condition.
if (Lower == Upper)
return ConstantRange(BitWidth, /*isFullSet=*/true);
break;
}
return ConstantRange(Lower, Upper);
}
CmpInst::Predicate CmpInst::getSwappedPredicate(Predicate pred) {
switch (pred) {
default: llvm_unreachable("Unknown cmp predicate!");
case ICMP_EQ: case ICMP_NE:
return pred;
case ICMP_SGT: return ICMP_SLT;
case ICMP_SLT: return ICMP_SGT;
case ICMP_SGE: return ICMP_SLE;
case ICMP_SLE: return ICMP_SGE;
case ICMP_UGT: return ICMP_ULT;
case ICMP_ULT: return ICMP_UGT;
case ICMP_UGE: return ICMP_ULE;
case ICMP_ULE: return ICMP_UGE;
case FCMP_FALSE: case FCMP_TRUE:
case FCMP_OEQ: case FCMP_ONE:
case FCMP_UEQ: case FCMP_UNE:
case FCMP_ORD: case FCMP_UNO:
return pred;
case FCMP_OGT: return FCMP_OLT;
case FCMP_OLT: return FCMP_OGT;
case FCMP_OGE: return FCMP_OLE;
case FCMP_OLE: return FCMP_OGE;
case FCMP_UGT: return FCMP_ULT;
case FCMP_ULT: return FCMP_UGT;
case FCMP_UGE: return FCMP_ULE;
case FCMP_ULE: return FCMP_UGE;
}
}
bool CmpInst::isUnsigned(unsigned short predicate) {
switch (predicate) {
default: return false;
case ICmpInst::ICMP_ULT: case ICmpInst::ICMP_ULE: case ICmpInst::ICMP_UGT:
case ICmpInst::ICMP_UGE: return true;
}
}
bool CmpInst::isSigned(unsigned short predicate) {
switch (predicate) {
default: return false;
case ICmpInst::ICMP_SLT: case ICmpInst::ICMP_SLE: case ICmpInst::ICMP_SGT:
case ICmpInst::ICMP_SGE: return true;
}
}
bool CmpInst::isOrdered(unsigned short predicate) {
switch (predicate) {
default: return false;
case FCmpInst::FCMP_OEQ: case FCmpInst::FCMP_ONE: case FCmpInst::FCMP_OGT:
case FCmpInst::FCMP_OLT: case FCmpInst::FCMP_OGE: case FCmpInst::FCMP_OLE:
case FCmpInst::FCMP_ORD: return true;
}
}
bool CmpInst::isUnordered(unsigned short predicate) {
switch (predicate) {
default: return false;
case FCmpInst::FCMP_UEQ: case FCmpInst::FCMP_UNE: case FCmpInst::FCMP_UGT:
case FCmpInst::FCMP_ULT: case FCmpInst::FCMP_UGE: case FCmpInst::FCMP_ULE:
case FCmpInst::FCMP_UNO: return true;
}
}
bool CmpInst::isTrueWhenEqual(unsigned short predicate) {
switch(predicate) {
default: return false;
case ICMP_EQ: case ICMP_UGE: case ICMP_ULE: case ICMP_SGE: case ICMP_SLE:
case FCMP_TRUE: case FCMP_UEQ: case FCMP_UGE: case FCMP_ULE: return true;
}
}
bool CmpInst::isFalseWhenEqual(unsigned short predicate) {
switch(predicate) {
case ICMP_NE: case ICMP_UGT: case ICMP_ULT: case ICMP_SGT: case ICMP_SLT:
case FCMP_FALSE: case FCMP_ONE: case FCMP_OGT: case FCMP_OLT: return true;
default: return false;
}
}
//===----------------------------------------------------------------------===//
// SwitchInst Implementation
//===----------------------------------------------------------------------===//
void SwitchInst::init(Value *Value, BasicBlock *Default, unsigned NumReserved) {
assert(Value && Default && NumReserved);
ReservedSpace = NumReserved;
setNumHungOffUseOperands(2);
allocHungoffUses(ReservedSpace);
Op<0>() = Value;
Op<1>() = Default;
}
/// SwitchInst ctor - Create a new switch instruction, specifying a value to
/// switch on and a default destination. The number of additional cases can
/// be specified here to make memory allocation more efficient. This
/// constructor can also autoinsert before another instruction.
SwitchInst::SwitchInst(Value *Value, BasicBlock *Default, unsigned NumCases,
Instruction *InsertBefore)
: TerminatorInst(Type::getVoidTy(Value->getContext()), Instruction::Switch,
nullptr, 0, InsertBefore) {
init(Value, Default, 2+NumCases*2);
}
/// SwitchInst ctor - Create a new switch instruction, specifying a value to
/// switch on and a default destination. The number of additional cases can
/// be specified here to make memory allocation more efficient. This
/// constructor also autoinserts at the end of the specified BasicBlock.
SwitchInst::SwitchInst(Value *Value, BasicBlock *Default, unsigned NumCases,
BasicBlock *InsertAtEnd)
: TerminatorInst(Type::getVoidTy(Value->getContext()), Instruction::Switch,
nullptr, 0, InsertAtEnd) {
init(Value, Default, 2+NumCases*2);
}
SwitchInst::SwitchInst(const SwitchInst &SI)
: TerminatorInst(SI.getType(), Instruction::Switch, nullptr, 0) {
init(SI.getCondition(), SI.getDefaultDest(), SI.getNumOperands());
setNumHungOffUseOperands(SI.getNumOperands());
Use *OL = getOperandList();
const Use *InOL = SI.getOperandList();
for (unsigned i = 2, E = SI.getNumOperands(); i != E; i += 2) {
OL[i] = InOL[i];
OL[i+1] = InOL[i+1];
}
SubclassOptionalData = SI.SubclassOptionalData;
}
/// addCase - Add an entry to the switch instruction...
///
void SwitchInst::addCase(ConstantInt *OnVal, BasicBlock *Dest) {
unsigned NewCaseIdx = getNumCases();
unsigned OpNo = getNumOperands();
if (OpNo+2 > ReservedSpace)
growOperands(); // Get more space!
// Initialize some new operands.
assert(OpNo+1 < ReservedSpace && "Growing didn't work!");
setNumHungOffUseOperands(OpNo+2);
CaseIt Case(this, NewCaseIdx);
Case.setValue(OnVal);
Case.setSuccessor(Dest);
}
/// removeCase - This method removes the specified case and its successor
/// from the switch instruction.
void SwitchInst::removeCase(CaseIt i) {
unsigned idx = i.getCaseIndex();
assert(2 + idx*2 < getNumOperands() && "Case index out of range!!!");
unsigned NumOps = getNumOperands();
Use *OL = getOperandList();
// Overwrite this case with the end of the list.
if (2 + (idx + 1) * 2 != NumOps) {
OL[2 + idx * 2] = OL[NumOps - 2];
OL[2 + idx * 2 + 1] = OL[NumOps - 1];
}
// Nuke the last value.
OL[NumOps-2].set(nullptr);
OL[NumOps-2+1].set(nullptr);
setNumHungOffUseOperands(NumOps-2);
}
/// growOperands - grow operands - This grows the operand list in response
/// to a push_back style of operation. This grows the number of ops by 3 times.
///
void SwitchInst::growOperands() {
unsigned e = getNumOperands();
unsigned NumOps = e*3;
ReservedSpace = NumOps;
growHungoffUses(ReservedSpace);
}
BasicBlock *SwitchInst::getSuccessorV(unsigned idx) const {
return getSuccessor(idx);
}
unsigned SwitchInst::getNumSuccessorsV() const {
return getNumSuccessors();
}
void SwitchInst::setSuccessorV(unsigned idx, BasicBlock *B) {
setSuccessor(idx, B);
}
//===----------------------------------------------------------------------===//
// IndirectBrInst Implementation
//===----------------------------------------------------------------------===//
void IndirectBrInst::init(Value *Address, unsigned NumDests) {
assert(Address && Address->getType()->isPointerTy() &&
"Address of indirectbr must be a pointer");
ReservedSpace = 1+NumDests;
setNumHungOffUseOperands(1);
allocHungoffUses(ReservedSpace);
Op<0>() = Address;
}
/// growOperands - grow operands - This grows the operand list in response
/// to a push_back style of operation. This grows the number of ops by 2 times.
///
void IndirectBrInst::growOperands() {
unsigned e = getNumOperands();
unsigned NumOps = e*2;
ReservedSpace = NumOps;
growHungoffUses(ReservedSpace);
}
IndirectBrInst::IndirectBrInst(Value *Address, unsigned NumCases,
Instruction *InsertBefore)
: TerminatorInst(Type::getVoidTy(Address->getContext()),Instruction::IndirectBr,
nullptr, 0, InsertBefore) {
init(Address, NumCases);
}
IndirectBrInst::IndirectBrInst(Value *Address, unsigned NumCases,
BasicBlock *InsertAtEnd)
: TerminatorInst(Type::getVoidTy(Address->getContext()),Instruction::IndirectBr,
nullptr, 0, InsertAtEnd) {
init(Address, NumCases);
}
IndirectBrInst::IndirectBrInst(const IndirectBrInst &IBI)
: TerminatorInst(Type::getVoidTy(IBI.getContext()), Instruction::IndirectBr,
nullptr, IBI.getNumOperands()) {
allocHungoffUses(IBI.getNumOperands());
Use *OL = getOperandList();
const Use *InOL = IBI.getOperandList();
for (unsigned i = 0, E = IBI.getNumOperands(); i != E; ++i)
OL[i] = InOL[i];
SubclassOptionalData = IBI.SubclassOptionalData;
}
/// addDestination - Add a destination.
///
void IndirectBrInst::addDestination(BasicBlock *DestBB) {
unsigned OpNo = getNumOperands();
if (OpNo+1 > ReservedSpace)
growOperands(); // Get more space!
// Initialize some new operands.
assert(OpNo < ReservedSpace && "Growing didn't work!");
setNumHungOffUseOperands(OpNo+1);
getOperandList()[OpNo] = DestBB;
}
/// removeDestination - This method removes the specified successor from the
/// indirectbr instruction.
void IndirectBrInst::removeDestination(unsigned idx) {
assert(idx < getNumOperands()-1 && "Successor index out of range!");
unsigned NumOps = getNumOperands();
Use *OL = getOperandList();
// Replace this value with the last one.
OL[idx+1] = OL[NumOps-1];
// Nuke the last value.
OL[NumOps-1].set(nullptr);
setNumHungOffUseOperands(NumOps-1);
}
BasicBlock *IndirectBrInst::getSuccessorV(unsigned idx) const {
return getSuccessor(idx);
}
unsigned IndirectBrInst::getNumSuccessorsV() const {
return getNumSuccessors();
}
void IndirectBrInst::setSuccessorV(unsigned idx, BasicBlock *B) {
setSuccessor(idx, B);
}
//===----------------------------------------------------------------------===//
// cloneImpl() implementations
//===----------------------------------------------------------------------===//
// Define these methods here so vtables don't get emitted into every translation
// unit that uses these classes.
GetElementPtrInst *GetElementPtrInst::cloneImpl() const {
return new (getNumOperands()) GetElementPtrInst(*this);
}
BinaryOperator *BinaryOperator::cloneImpl() const {
return Create(getOpcode(), Op<0>(), Op<1>());
}
FCmpInst *FCmpInst::cloneImpl() const {
return new FCmpInst(getPredicate(), Op<0>(), Op<1>());
}
ICmpInst *ICmpInst::cloneImpl() const {
return new ICmpInst(getPredicate(), Op<0>(), Op<1>());
}
ExtractValueInst *ExtractValueInst::cloneImpl() const {
return new ExtractValueInst(*this);
}
InsertValueInst *InsertValueInst::cloneImpl() const {
return new InsertValueInst(*this);
}
AllocaInst *AllocaInst::cloneImpl() const {
AllocaInst *Result = new AllocaInst(getAllocatedType(),
(Value *)getOperand(0), getAlignment());
Result->setUsedWithInAlloca(isUsedWithInAlloca());
return Result;
}
LoadInst *LoadInst::cloneImpl() const {
return new LoadInst(getOperand(0), Twine(), isVolatile(),
getAlignment(), getOrdering(), getSynchScope());
}
StoreInst *StoreInst::cloneImpl() const {
return new StoreInst(getOperand(0), getOperand(1), isVolatile(),
getAlignment(), getOrdering(), getSynchScope());
}
AtomicCmpXchgInst *AtomicCmpXchgInst::cloneImpl() const {
AtomicCmpXchgInst *Result =
new AtomicCmpXchgInst(getOperand(0), getOperand(1), getOperand(2),
getSuccessOrdering(), getFailureOrdering(),
getSynchScope());
Result->setVolatile(isVolatile());
Result->setWeak(isWeak());
return Result;
}
AtomicRMWInst *AtomicRMWInst::cloneImpl() const {
AtomicRMWInst *Result =
new AtomicRMWInst(getOperation(),getOperand(0), getOperand(1),
getOrdering(), getSynchScope());
Result->setVolatile(isVolatile());
return Result;
}
FenceInst *FenceInst::cloneImpl() const {
return new FenceInst(getContext(), getOrdering(), getSynchScope());
}
TruncInst *TruncInst::cloneImpl() const {
return new TruncInst(getOperand(0), getType());
}
ZExtInst *ZExtInst::cloneImpl() const {
return new ZExtInst(getOperand(0), getType());
}
SExtInst *SExtInst::cloneImpl() const {
return new SExtInst(getOperand(0), getType());
}
FPTruncInst *FPTruncInst::cloneImpl() const {
return new FPTruncInst(getOperand(0), getType());
}
FPExtInst *FPExtInst::cloneImpl() const {
return new FPExtInst(getOperand(0), getType());
}
UIToFPInst *UIToFPInst::cloneImpl() const {
return new UIToFPInst(getOperand(0), getType());
}
SIToFPInst *SIToFPInst::cloneImpl() const {
return new SIToFPInst(getOperand(0), getType());
}
FPToUIInst *FPToUIInst::cloneImpl() const {
return new FPToUIInst(getOperand(0), getType());
}
FPToSIInst *FPToSIInst::cloneImpl() const {
return new FPToSIInst(getOperand(0), getType());
}
PtrToIntInst *PtrToIntInst::cloneImpl() const {
return new PtrToIntInst(getOperand(0), getType());
}
IntToPtrInst *IntToPtrInst::cloneImpl() const {
return new IntToPtrInst(getOperand(0), getType());
}
BitCastInst *BitCastInst::cloneImpl() const {
return new BitCastInst(getOperand(0), getType());
}
AddrSpaceCastInst *AddrSpaceCastInst::cloneImpl() const {
return new AddrSpaceCastInst(getOperand(0), getType());
}
CallInst *CallInst::cloneImpl() const {
return new(getNumOperands()) CallInst(*this);
}
SelectInst *SelectInst::cloneImpl() const {
return SelectInst::Create(getOperand(0), getOperand(1), getOperand(2));
}
VAArgInst *VAArgInst::cloneImpl() const {
return new VAArgInst(getOperand(0), getType());
}
ExtractElementInst *ExtractElementInst::cloneImpl() const {
return ExtractElementInst::Create(getOperand(0), getOperand(1));
}
InsertElementInst *InsertElementInst::cloneImpl() const {
return InsertElementInst::Create(getOperand(0), getOperand(1), getOperand(2));
}
ShuffleVectorInst *ShuffleVectorInst::cloneImpl() const {
return new ShuffleVectorInst(getOperand(0), getOperand(1), getOperand(2));
}
PHINode *PHINode::cloneImpl() const { return new PHINode(*this); }
LandingPadInst *LandingPadInst::cloneImpl() const {
return new LandingPadInst(*this);
}
ReturnInst *ReturnInst::cloneImpl() const {
return new(getNumOperands()) ReturnInst(*this);
}
BranchInst *BranchInst::cloneImpl() const {
return new(getNumOperands()) BranchInst(*this);
}
SwitchInst *SwitchInst::cloneImpl() const { return new SwitchInst(*this); }
IndirectBrInst *IndirectBrInst::cloneImpl() const {
return new IndirectBrInst(*this);
}
InvokeInst *InvokeInst::cloneImpl() const {
return new(getNumOperands()) InvokeInst(*this);
}
ResumeInst *ResumeInst::cloneImpl() const { return new (1) ResumeInst(*this); }
UnreachableInst *UnreachableInst::cloneImpl() const {
LLVMContext &Context = getContext();
return new UnreachableInst(Context);
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/Use.cpp | //===-- Use.cpp - Implement the Use class ---------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/Use.h"
#include "llvm/IR/User.h"
#include "llvm/IR/Value.h"
#include <new>
namespace llvm {
void Use::swap(Use &RHS) {
if (Val == RHS.Val)
return;
if (Val)
removeFromList();
Value *OldVal = Val;
if (RHS.Val) {
RHS.removeFromList();
Val = RHS.Val;
Val->addUse(*this);
} else {
Val = nullptr;
}
if (OldVal) {
RHS.Val = OldVal;
RHS.Val->addUse(RHS);
} else {
RHS.Val = nullptr;
}
}
User *Use::getUser() const {
const Use *End = getImpliedUser();
const UserRef *ref = reinterpret_cast<const UserRef *>(End);
return ref->getInt() ? ref->getPointer()
: reinterpret_cast<User *>(const_cast<Use *>(End));
}
unsigned Use::getOperandNo() const {
return this - getUser()->op_begin();
}
// Sets up the waymarking algorithm's tags for a series of Uses. See the
// algorithm details here:
//
// http://www.llvm.org/docs/ProgrammersManual.html#the-waymarking-algorithm
//
Use *Use::initTags(Use *const Start, Use *Stop) {
ptrdiff_t Done = 0;
while (Done < 20) {
if (Start == Stop--)
return Start;
static const PrevPtrTag tags[20] = {
fullStopTag, oneDigitTag, stopTag, oneDigitTag, oneDigitTag,
stopTag, zeroDigitTag, oneDigitTag, oneDigitTag, stopTag,
zeroDigitTag, oneDigitTag, zeroDigitTag, oneDigitTag, stopTag,
oneDigitTag, oneDigitTag, oneDigitTag, oneDigitTag, stopTag};
new (Stop) Use(tags[Done++]);
}
ptrdiff_t Count = Done;
while (Start != Stop) {
--Stop;
if (!Count) {
new (Stop) Use(stopTag);
++Done;
Count = Done;
} else {
new (Stop) Use(PrevPtrTag(Count & 1));
Count >>= 1;
++Done;
}
}
return Start;
}
void Use::zap(Use *Start, const Use *Stop, bool del) {
while (Start != Stop)
(--Stop)->~Use();
if (del)
::operator delete(Start);
}
const Use *Use::getImpliedUser() const {
const Use *Current = this;
while (true) {
unsigned Tag = (Current++)->Prev.getInt();
switch (Tag) {
case zeroDigitTag:
case oneDigitTag:
continue;
case stopTag: {
++Current;
ptrdiff_t Offset = 1;
while (true) {
unsigned Tag = Current->Prev.getInt();
switch (Tag) {
case zeroDigitTag:
case oneDigitTag:
++Current;
Offset = (Offset << 1) + Tag;
continue;
default:
return Current + Offset;
}
}
}
case fullStopTag:
return Current;
}
}
}
} // End llvm namespace
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/AutoUpgrade.cpp | //===-- AutoUpgrade.cpp - Implement auto-upgrade helper functions ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the auto-upgrade helper functions.
// This is where deprecated IR intrinsics and other IR features are updated to
// current specifications.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/AutoUpgrade.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DIBuilder.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/DiagnosticInfo.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/ErrorHandling.h"
#include <cstring>
using namespace llvm;
#if 0 // HLSL Change - remove platform intrinsics
// Upgrade the declarations of the SSE4.1 functions whose arguments have
// changed their type from v4f32 to v2i64.
static bool UpgradeSSE41Function(Function* F, Intrinsic::ID IID,
Function *&NewFn) {
// Check whether this is an old version of the function, which received
// v4f32 arguments.
Type *Arg0Type = F->getFunctionType()->getParamType(0);
if (Arg0Type != VectorType::get(Type::getFloatTy(F->getContext()), 4))
return false;
// Yes, it's old, replace it with new version.
F->setName(F->getName() + ".old");
NewFn = Intrinsic::getDeclaration(F->getParent(), IID);
return true;
}
// Upgrade the declarations of intrinsic functions whose 8-bit immediate mask
// arguments have changed their type from i32 to i8.
static bool UpgradeX86IntrinsicsWith8BitMask(Function *F, Intrinsic::ID IID,
Function *&NewFn) {
// Check that the last argument is an i32.
Type *LastArgType = F->getFunctionType()->getParamType(
F->getFunctionType()->getNumParams() - 1);
if (!LastArgType->isIntegerTy(32))
return false;
// Move this function aside and map down.
F->setName(F->getName() + ".old");
NewFn = Intrinsic::getDeclaration(F->getParent(), IID);
return true;
}
#endif // HLSL Change - remove platform intrinsics
static bool UpgradeIntrinsicFunction1(Function *F, Function *&NewFn) {
assert(F && "Illegal to upgrade a non-existent Function.");
// Quickly eliminate it, if it's not a candidate.
StringRef Name = F->getName();
if (Name.size() <= 8 || !Name.startswith("llvm."))
return false;
Name = Name.substr(5); // Strip off "llvm."
switch (Name[0]) {
default: break;
case 'a': {
if (Name.startswith("arm.neon.vclz")) {
Type* args[2] = {
F->arg_begin()->getType(),
Type::getInt1Ty(F->getContext())
};
// Can't use Intrinsic::getDeclaration here as it adds a ".i1" to
// the end of the name. Change name from llvm.arm.neon.vclz.* to
// llvm.ctlz.*
FunctionType* fType = FunctionType::get(F->getReturnType(), args, false);
NewFn = Function::Create(fType, F->getLinkage(),
"llvm.ctlz." + Name.substr(14), F->getParent());
return true;
}
if (Name.startswith("arm.neon.vcnt")) {
NewFn = Intrinsic::getDeclaration(F->getParent(), Intrinsic::ctpop,
F->arg_begin()->getType());
return true;
}
break;
}
case 'c': {
if (Name.startswith("ctlz.") && F->arg_size() == 1) {
F->setName(Name + ".old");
NewFn = Intrinsic::getDeclaration(F->getParent(), Intrinsic::ctlz,
F->arg_begin()->getType());
return true;
}
if (Name.startswith("cttz.") && F->arg_size() == 1) {
F->setName(Name + ".old");
NewFn = Intrinsic::getDeclaration(F->getParent(), Intrinsic::cttz,
F->arg_begin()->getType());
return true;
}
break;
}
case 'o':
// We only need to change the name to match the mangling including the
// address space.
if (F->arg_size() == 2 && Name.startswith("objectsize.")) {
Type *Tys[2] = { F->getReturnType(), F->arg_begin()->getType() };
if (F->getName() != Intrinsic::getName(Intrinsic::objectsize, Tys)) {
F->setName(Name + ".old");
NewFn = Intrinsic::getDeclaration(F->getParent(),
Intrinsic::objectsize, Tys);
return true;
}
}
break;
#if 0 // HLSL Change - remove platform intrinsics
case 'x': {
if (Name.startswith("x86.sse2.pcmpeq.") ||
Name.startswith("x86.sse2.pcmpgt.") ||
Name.startswith("x86.avx2.pcmpeq.") ||
Name.startswith("x86.avx2.pcmpgt.") ||
Name.startswith("x86.avx.vpermil.") ||
Name == "x86.avx.vinsertf128.pd.256" ||
Name == "x86.avx.vinsertf128.ps.256" ||
Name == "x86.avx.vinsertf128.si.256" ||
Name == "x86.avx2.vinserti128" ||
Name == "x86.avx.vextractf128.pd.256" ||
Name == "x86.avx.vextractf128.ps.256" ||
Name == "x86.avx.vextractf128.si.256" ||
Name == "x86.avx2.vextracti128" ||
Name == "x86.avx.movnt.dq.256" ||
Name == "x86.avx.movnt.pd.256" ||
Name == "x86.avx.movnt.ps.256" ||
Name == "x86.sse42.crc32.64.8" ||
Name == "x86.avx.vbroadcast.ss" ||
Name == "x86.avx.vbroadcast.ss.256" ||
Name == "x86.avx.vbroadcast.sd.256" ||
Name == "x86.sse2.psll.dq" ||
Name == "x86.sse2.psrl.dq" ||
Name == "x86.avx2.psll.dq" ||
Name == "x86.avx2.psrl.dq" ||
Name == "x86.sse2.psll.dq.bs" ||
Name == "x86.sse2.psrl.dq.bs" ||
Name == "x86.avx2.psll.dq.bs" ||
Name == "x86.avx2.psrl.dq.bs" ||
Name == "x86.sse41.pblendw" ||
Name == "x86.sse41.blendpd" ||
Name == "x86.sse41.blendps" ||
Name == "x86.avx.blend.pd.256" ||
Name == "x86.avx.blend.ps.256" ||
Name == "x86.avx2.pblendw" ||
Name == "x86.avx2.pblendd.128" ||
Name == "x86.avx2.pblendd.256" ||
Name == "x86.avx2.vbroadcasti128" ||
(Name.startswith("x86.xop.vpcom") && F->arg_size() == 2)) {
NewFn = nullptr;
return true;
}
// SSE4.1 ptest functions may have an old signature.
if (Name.startswith("x86.sse41.ptest")) {
if (Name == "x86.sse41.ptestc")
return UpgradeSSE41Function(F, Intrinsic::x86_sse41_ptestc, NewFn);
if (Name == "x86.sse41.ptestz")
return UpgradeSSE41Function(F, Intrinsic::x86_sse41_ptestz, NewFn);
if (Name == "x86.sse41.ptestnzc")
return UpgradeSSE41Function(F, Intrinsic::x86_sse41_ptestnzc, NewFn);
}
// Several blend and other instructions with masks used the wrong number of
// bits.
if (Name == "x86.sse41.insertps")
return UpgradeX86IntrinsicsWith8BitMask(F, Intrinsic::x86_sse41_insertps,
NewFn);
if (Name == "x86.sse41.dppd")
return UpgradeX86IntrinsicsWith8BitMask(F, Intrinsic::x86_sse41_dppd,
NewFn);
if (Name == "x86.sse41.dpps")
return UpgradeX86IntrinsicsWith8BitMask(F, Intrinsic::x86_sse41_dpps,
NewFn);
if (Name == "x86.sse41.mpsadbw")
return UpgradeX86IntrinsicsWith8BitMask(F, Intrinsic::x86_sse41_mpsadbw,
NewFn);
if (Name == "x86.avx.dp.ps.256")
return UpgradeX86IntrinsicsWith8BitMask(F, Intrinsic::x86_avx_dp_ps_256,
NewFn);
if (Name == "x86.avx2.mpsadbw")
return UpgradeX86IntrinsicsWith8BitMask(F, Intrinsic::x86_avx2_mpsadbw,
NewFn);
// frcz.ss/sd may need to have an argument dropped
if (Name.startswith("x86.xop.vfrcz.ss") && F->arg_size() == 2) {
F->setName(Name + ".old");
NewFn = Intrinsic::getDeclaration(F->getParent(),
Intrinsic::x86_xop_vfrcz_ss);
return true;
}
if (Name.startswith("x86.xop.vfrcz.sd") && F->arg_size() == 2) {
F->setName(Name + ".old");
NewFn = Intrinsic::getDeclaration(F->getParent(),
Intrinsic::x86_xop_vfrcz_sd);
return true;
}
// Fix the FMA4 intrinsics to remove the 4
if (Name.startswith("x86.fma4.")) {
F->setName("llvm.x86.fma" + Name.substr(8));
NewFn = F;
return true;
}
break;
}
#endif // HLSL Change - remove platform intrinsics
}
// This may not belong here. This function is effectively being overloaded
// to both detect an intrinsic which needs upgrading, and to provide the
// upgraded form of the intrinsic. We should perhaps have two separate
// functions for this.
return false;
}
bool llvm::UpgradeIntrinsicFunction(Function *F, Function *&NewFn) {
NewFn = nullptr;
bool Upgraded = UpgradeIntrinsicFunction1(F, NewFn);
assert(F != NewFn && "Intrinsic function upgraded to the same function");
// Upgrade intrinsic attributes. This does not change the function.
if (NewFn)
F = NewFn;
if (Intrinsic::ID id = F->getIntrinsicID())
F->setAttributes(Intrinsic::getAttributes(F->getContext(), id));
return Upgraded;
}
bool llvm::UpgradeGlobalVariable(GlobalVariable *GV) {
// Nothing to do yet.
return false;
}
#if 0 // HLSL Change - remove platform intrinsics
// Handles upgrading SSE2 and AVX2 PSLLDQ intrinsics by converting them
// to byte shuffles.
static Value *UpgradeX86PSLLDQIntrinsics(IRBuilder<> &Builder, LLVMContext &C,
Value *Op, unsigned NumLanes,
unsigned Shift) {
// Each lane is 16 bytes.
unsigned NumElts = NumLanes * 16;
// Bitcast from a 64-bit element type to a byte element type.
Op = Builder.CreateBitCast(Op,
VectorType::get(Type::getInt8Ty(C), NumElts),
"cast");
// We'll be shuffling in zeroes.
Value *Res = ConstantVector::getSplat(NumElts, Builder.getInt8(0));
// If shift is less than 16, emit a shuffle to move the bytes. Otherwise,
// we'll just return the zero vector.
if (Shift < 16) {
SmallVector<Constant*, 32> Idxs;
// 256-bit version is split into two 16-byte lanes.
for (unsigned l = 0; l != NumElts; l += 16)
for (unsigned i = 0; i != 16; ++i) {
unsigned Idx = NumElts + i - Shift;
if (Idx < NumElts)
Idx -= NumElts - 16; // end of lane, switch operand.
Idxs.push_back(Builder.getInt32(Idx + l));
}
Res = Builder.CreateShuffleVector(Res, Op, ConstantVector::get(Idxs));
}
// Bitcast back to a 64-bit element type.
return Builder.CreateBitCast(Res,
VectorType::get(Type::getInt64Ty(C), 2*NumLanes),
"cast");
}
// Handles upgrading SSE2 and AVX2 PSRLDQ intrinsics by converting them
// to byte shuffles.
static Value *UpgradeX86PSRLDQIntrinsics(IRBuilder<> &Builder, LLVMContext &C,
Value *Op, unsigned NumLanes,
unsigned Shift) {
// Each lane is 16 bytes.
unsigned NumElts = NumLanes * 16;
// Bitcast from a 64-bit element type to a byte element type.
Op = Builder.CreateBitCast(Op,
VectorType::get(Type::getInt8Ty(C), NumElts),
"cast");
// We'll be shuffling in zeroes.
Value *Res = ConstantVector::getSplat(NumElts, Builder.getInt8(0));
// If shift is less than 16, emit a shuffle to move the bytes. Otherwise,
// we'll just return the zero vector.
if (Shift < 16) {
SmallVector<Constant*, 32> Idxs;
// 256-bit version is split into two 16-byte lanes.
for (unsigned l = 0; l != NumElts; l += 16)
for (unsigned i = 0; i != 16; ++i) {
unsigned Idx = i + Shift;
if (Idx >= 16)
Idx += NumElts - 16; // end of lane, switch operand.
Idxs.push_back(Builder.getInt32(Idx + l));
}
Res = Builder.CreateShuffleVector(Op, Res, ConstantVector::get(Idxs));
}
// Bitcast back to a 64-bit element type.
return Builder.CreateBitCast(Res,
VectorType::get(Type::getInt64Ty(C), 2*NumLanes),
"cast");
}
#endif // HLSL Change - remove platform intrinsics
// UpgradeIntrinsicCall - Upgrade a call to an old intrinsic to be a call the
// upgraded intrinsic. All argument and return casting must be provided in
// order to seamlessly integrate with existing context.
void llvm::UpgradeIntrinsicCall(CallInst *CI, Function *NewFn) {
Function *F = CI->getCalledFunction();
LLVMContext &C = CI->getContext();
IRBuilder<> Builder(C);
Builder.SetInsertPoint(CI->getParent(), CI);
assert(F && "Intrinsic call is not direct?");
if (!NewFn) {
(void)F; // HLSL Change - unused local variable
#if 0 // HLSL Change - remove platform intrinsics
// Get the Function's name.
StringRef Name = F->getName();
Value *Rep;
// Upgrade packed integer vector compares intrinsics to compare instructions
if (Name.startswith("llvm.x86.sse2.pcmpeq.") ||
Name.startswith("llvm.x86.avx2.pcmpeq.")) {
Rep = Builder.CreateICmpEQ(CI->getArgOperand(0), CI->getArgOperand(1),
"pcmpeq");
// need to sign extend since icmp returns vector of i1
Rep = Builder.CreateSExt(Rep, CI->getType(), "");
} else if (Name.startswith("llvm.x86.sse2.pcmpgt.") ||
Name.startswith("llvm.x86.avx2.pcmpgt.")) {
Rep = Builder.CreateICmpSGT(CI->getArgOperand(0), CI->getArgOperand(1),
"pcmpgt");
// need to sign extend since icmp returns vector of i1
Rep = Builder.CreateSExt(Rep, CI->getType(), "");
} else if (Name == "llvm.x86.avx.movnt.dq.256" ||
Name == "llvm.x86.avx.movnt.ps.256" ||
Name == "llvm.x86.avx.movnt.pd.256") {
IRBuilder<> Builder(C);
Builder.SetInsertPoint(CI->getParent(), CI);
Module *M = F->getParent();
SmallVector<Metadata *, 1> Elts;
Elts.push_back(
ConstantAsMetadata::get(ConstantInt::get(Type::getInt32Ty(C), 1)));
MDNode *Node = MDNode::get(C, Elts);
Value *Arg0 = CI->getArgOperand(0);
Value *Arg1 = CI->getArgOperand(1);
// Convert the type of the pointer to a pointer to the stored type.
Value *BC = Builder.CreateBitCast(Arg0,
PointerType::getUnqual(Arg1->getType()),
"cast");
StoreInst *SI = Builder.CreateStore(Arg1, BC);
SI->setMetadata(M->getMDKindID("nontemporal"), Node);
SI->setAlignment(16);
// Remove intrinsic.
CI->eraseFromParent();
return;
} else if (Name.startswith("llvm.x86.xop.vpcom")) {
Intrinsic::ID intID;
if (Name.endswith("ub"))
intID = Intrinsic::x86_xop_vpcomub;
else if (Name.endswith("uw"))
intID = Intrinsic::x86_xop_vpcomuw;
else if (Name.endswith("ud"))
intID = Intrinsic::x86_xop_vpcomud;
else if (Name.endswith("uq"))
intID = Intrinsic::x86_xop_vpcomuq;
else if (Name.endswith("b"))
intID = Intrinsic::x86_xop_vpcomb;
else if (Name.endswith("w"))
intID = Intrinsic::x86_xop_vpcomw;
else if (Name.endswith("d"))
intID = Intrinsic::x86_xop_vpcomd;
else if (Name.endswith("q"))
intID = Intrinsic::x86_xop_vpcomq;
else
llvm_unreachable("Unknown suffix");
Name = Name.substr(18); // strip off "llvm.x86.xop.vpcom"
unsigned Imm;
if (Name.startswith("lt"))
Imm = 0;
else if (Name.startswith("le"))
Imm = 1;
else if (Name.startswith("gt"))
Imm = 2;
else if (Name.startswith("ge"))
Imm = 3;
else if (Name.startswith("eq"))
Imm = 4;
else if (Name.startswith("ne"))
Imm = 5;
else if (Name.startswith("false"))
Imm = 6;
else if (Name.startswith("true"))
Imm = 7;
else
llvm_unreachable("Unknown condition");
Function *VPCOM = Intrinsic::getDeclaration(F->getParent(), intID);
Rep =
Builder.CreateCall(VPCOM, {CI->getArgOperand(0), CI->getArgOperand(1),
Builder.getInt8(Imm)});
} else if (Name == "llvm.x86.sse42.crc32.64.8") {
Function *CRC32 = Intrinsic::getDeclaration(F->getParent(),
Intrinsic::x86_sse42_crc32_32_8);
Value *Trunc0 = Builder.CreateTrunc(CI->getArgOperand(0), Type::getInt32Ty(C));
Rep = Builder.CreateCall(CRC32, {Trunc0, CI->getArgOperand(1)});
Rep = Builder.CreateZExt(Rep, CI->getType(), "");
} else if (Name.startswith("llvm.x86.avx.vbroadcast")) {
// Replace broadcasts with a series of insertelements.
Type *VecTy = CI->getType();
Type *EltTy = VecTy->getVectorElementType();
unsigned EltNum = VecTy->getVectorNumElements();
Value *Cast = Builder.CreateBitCast(CI->getArgOperand(0),
EltTy->getPointerTo());
Value *Load = Builder.CreateLoad(EltTy, Cast);
Type *I32Ty = Type::getInt32Ty(C);
Rep = UndefValue::get(VecTy);
for (unsigned I = 0; I < EltNum; ++I)
Rep = Builder.CreateInsertElement(Rep, Load,
ConstantInt::get(I32Ty, I));
} else if (Name == "llvm.x86.avx2.vbroadcasti128") {
// Replace vbroadcasts with a vector shuffle.
Type *VT = VectorType::get(Type::getInt64Ty(C), 2);
Value *Op = Builder.CreatePointerCast(CI->getArgOperand(0),
PointerType::getUnqual(VT));
Value *Load = Builder.CreateLoad(VT, Op);
const int Idxs[4] = { 0, 1, 0, 1 };
Rep = Builder.CreateShuffleVector(Load, UndefValue::get(Load->getType()),
Idxs);
} else if (Name == "llvm.x86.sse2.psll.dq") {
// 128-bit shift left specified in bits.
unsigned Shift = cast<ConstantInt>(CI->getArgOperand(1))->getZExtValue();
Rep = UpgradeX86PSLLDQIntrinsics(Builder, C, CI->getArgOperand(0), 1,
Shift / 8); // Shift is in bits.
} else if (Name == "llvm.x86.sse2.psrl.dq") {
// 128-bit shift right specified in bits.
unsigned Shift = cast<ConstantInt>(CI->getArgOperand(1))->getZExtValue();
Rep = UpgradeX86PSRLDQIntrinsics(Builder, C, CI->getArgOperand(0), 1,
Shift / 8); // Shift is in bits.
} else if (Name == "llvm.x86.avx2.psll.dq") {
// 256-bit shift left specified in bits.
unsigned Shift = cast<ConstantInt>(CI->getArgOperand(1))->getZExtValue();
Rep = UpgradeX86PSLLDQIntrinsics(Builder, C, CI->getArgOperand(0), 2,
Shift / 8); // Shift is in bits.
} else if (Name == "llvm.x86.avx2.psrl.dq") {
// 256-bit shift right specified in bits.
unsigned Shift = cast<ConstantInt>(CI->getArgOperand(1))->getZExtValue();
Rep = UpgradeX86PSRLDQIntrinsics(Builder, C, CI->getArgOperand(0), 2,
Shift / 8); // Shift is in bits.
} else if (Name == "llvm.x86.sse2.psll.dq.bs") {
// 128-bit shift left specified in bytes.
unsigned Shift = cast<ConstantInt>(CI->getArgOperand(1))->getZExtValue();
Rep = UpgradeX86PSLLDQIntrinsics(Builder, C, CI->getArgOperand(0), 1,
Shift);
} else if (Name == "llvm.x86.sse2.psrl.dq.bs") {
// 128-bit shift right specified in bytes.
unsigned Shift = cast<ConstantInt>(CI->getArgOperand(1))->getZExtValue();
Rep = UpgradeX86PSRLDQIntrinsics(Builder, C, CI->getArgOperand(0), 1,
Shift);
} else if (Name == "llvm.x86.avx2.psll.dq.bs") {
// 256-bit shift left specified in bytes.
unsigned Shift = cast<ConstantInt>(CI->getArgOperand(1))->getZExtValue();
Rep = UpgradeX86PSLLDQIntrinsics(Builder, C, CI->getArgOperand(0), 2,
Shift);
} else if (Name == "llvm.x86.avx2.psrl.dq.bs") {
// 256-bit shift right specified in bytes.
unsigned Shift = cast<ConstantInt>(CI->getArgOperand(1))->getZExtValue();
Rep = UpgradeX86PSRLDQIntrinsics(Builder, C, CI->getArgOperand(0), 2,
Shift);
} else if (Name == "llvm.x86.sse41.pblendw" ||
Name == "llvm.x86.sse41.blendpd" ||
Name == "llvm.x86.sse41.blendps" ||
Name == "llvm.x86.avx.blend.pd.256" ||
Name == "llvm.x86.avx.blend.ps.256" ||
Name == "llvm.x86.avx2.pblendw" ||
Name == "llvm.x86.avx2.pblendd.128" ||
Name == "llvm.x86.avx2.pblendd.256") {
Value *Op0 = CI->getArgOperand(0);
Value *Op1 = CI->getArgOperand(1);
unsigned Imm = cast <ConstantInt>(CI->getArgOperand(2))->getZExtValue();
VectorType *VecTy = cast<VectorType>(CI->getType());
unsigned NumElts = VecTy->getNumElements();
SmallVector<Constant*, 16> Idxs;
for (unsigned i = 0; i != NumElts; ++i) {
unsigned Idx = ((Imm >> (i%8)) & 1) ? i + NumElts : i;
Idxs.push_back(Builder.getInt32(Idx));
}
Rep = Builder.CreateShuffleVector(Op0, Op1, ConstantVector::get(Idxs));
} else if (Name == "llvm.x86.avx.vinsertf128.pd.256" ||
Name == "llvm.x86.avx.vinsertf128.ps.256" ||
Name == "llvm.x86.avx.vinsertf128.si.256" ||
Name == "llvm.x86.avx2.vinserti128") {
Value *Op0 = CI->getArgOperand(0);
Value *Op1 = CI->getArgOperand(1);
unsigned Imm = cast<ConstantInt>(CI->getArgOperand(2))->getZExtValue();
VectorType *VecTy = cast<VectorType>(CI->getType());
unsigned NumElts = VecTy->getNumElements();
// Mask off the high bits of the immediate value; hardware ignores those.
Imm = Imm & 1;
// Extend the second operand into a vector that is twice as big.
Value *UndefV = UndefValue::get(Op1->getType());
SmallVector<Constant*, 8> Idxs;
for (unsigned i = 0; i != NumElts; ++i) {
Idxs.push_back(Builder.getInt32(i));
}
Rep = Builder.CreateShuffleVector(Op1, UndefV, ConstantVector::get(Idxs));
// Insert the second operand into the first operand.
// Note that there is no guarantee that instruction lowering will actually
// produce a vinsertf128 instruction for the created shuffles. In
// particular, the 0 immediate case involves no lane changes, so it can
// be handled as a blend.
// Example of shuffle mask for 32-bit elements:
// Imm = 1 <i32 0, i32 1, i32 2, i32 3, i32 8, i32 9, i32 10, i32 11>
// Imm = 0 <i32 8, i32 9, i32 10, i32 11, i32 4, i32 5, i32 6, i32 7 >
SmallVector<Constant*, 8> Idxs2;
// The low half of the result is either the low half of the 1st operand
// or the low half of the 2nd operand (the inserted vector).
for (unsigned i = 0; i != NumElts / 2; ++i) {
unsigned Idx = Imm ? i : (i + NumElts);
Idxs2.push_back(Builder.getInt32(Idx));
}
// The high half of the result is either the low half of the 2nd operand
// (the inserted vector) or the high half of the 1st operand.
for (unsigned i = NumElts / 2; i != NumElts; ++i) {
unsigned Idx = Imm ? (i + NumElts / 2) : i;
Idxs2.push_back(Builder.getInt32(Idx));
}
Rep = Builder.CreateShuffleVector(Op0, Rep, ConstantVector::get(Idxs2));
} else if (Name == "llvm.x86.avx.vextractf128.pd.256" ||
Name == "llvm.x86.avx.vextractf128.ps.256" ||
Name == "llvm.x86.avx.vextractf128.si.256" ||
Name == "llvm.x86.avx2.vextracti128") {
Value *Op0 = CI->getArgOperand(0);
unsigned Imm = cast<ConstantInt>(CI->getArgOperand(1))->getZExtValue();
VectorType *VecTy = cast<VectorType>(CI->getType());
unsigned NumElts = VecTy->getNumElements();
// Mask off the high bits of the immediate value; hardware ignores those.
Imm = Imm & 1;
// Get indexes for either the high half or low half of the input vector.
SmallVector<Constant*, 4> Idxs(NumElts);
for (unsigned i = 0; i != NumElts; ++i) {
unsigned Idx = Imm ? (i + NumElts) : i;
Idxs[i] = Builder.getInt32(Idx);
}
Value *UndefV = UndefValue::get(Op0->getType());
Rep = Builder.CreateShuffleVector(Op0, UndefV, ConstantVector::get(Idxs));
} else {
bool PD128 = false, PD256 = false, PS128 = false, PS256 = false;
if (Name == "llvm.x86.avx.vpermil.pd.256")
PD256 = true;
else if (Name == "llvm.x86.avx.vpermil.pd")
PD128 = true;
else if (Name == "llvm.x86.avx.vpermil.ps.256")
PS256 = true;
else if (Name == "llvm.x86.avx.vpermil.ps")
PS128 = true;
if (PD256 || PD128 || PS256 || PS128) {
Value *Op0 = CI->getArgOperand(0);
unsigned Imm = cast<ConstantInt>(CI->getArgOperand(1))->getZExtValue();
SmallVector<Constant*, 8> Idxs;
if (PD128)
for (unsigned i = 0; i != 2; ++i)
Idxs.push_back(Builder.getInt32((Imm >> i) & 0x1));
else if (PD256)
for (unsigned l = 0; l != 4; l+=2)
for (unsigned i = 0; i != 2; ++i)
Idxs.push_back(Builder.getInt32(((Imm >> (l+i)) & 0x1) + l));
else if (PS128)
for (unsigned i = 0; i != 4; ++i)
Idxs.push_back(Builder.getInt32((Imm >> (2 * i)) & 0x3));
else if (PS256)
for (unsigned l = 0; l != 8; l+=4)
for (unsigned i = 0; i != 4; ++i)
Idxs.push_back(Builder.getInt32(((Imm >> (2 * i)) & 0x3) + l));
else
llvm_unreachable("Unexpected function");
Rep = Builder.CreateShuffleVector(Op0, Op0, ConstantVector::get(Idxs));
} else {
llvm_unreachable("Unknown function for CallInst upgrade.");
}
}
CI->replaceAllUsesWith(Rep);
CI->eraseFromParent();
#endif // HLSL Change - remove platform intrinsics
llvm_unreachable("HLSL - should not be upgrading platform intrinsics."); // HLSL Change - remove platform intrinsics
return;
}
std::string Name = CI->getName();
if (!Name.empty())
CI->setName(Name + ".old");
switch (NewFn->getIntrinsicID()) {
default:
llvm_unreachable("Unknown function for CallInst upgrade.");
case Intrinsic::ctlz:
case Intrinsic::cttz:
assert(CI->getNumArgOperands() == 1 &&
"Mismatch between function args and call args");
CI->replaceAllUsesWith(Builder.CreateCall(
NewFn, {CI->getArgOperand(0), Builder.getFalse()}, Name));
CI->eraseFromParent();
return;
case Intrinsic::objectsize:
CI->replaceAllUsesWith(Builder.CreateCall(
NewFn, {CI->getArgOperand(0), CI->getArgOperand(1)}, Name));
CI->eraseFromParent();
return;
case Intrinsic::ctpop: {
CI->replaceAllUsesWith(Builder.CreateCall(NewFn, {CI->getArgOperand(0)}));
CI->eraseFromParent();
return;
}
#if 0 // HLSL Change - remove platform intrinsics
case Intrinsic::x86_xop_vfrcz_ss:
case Intrinsic::x86_xop_vfrcz_sd:
CI->replaceAllUsesWith(
Builder.CreateCall(NewFn, {CI->getArgOperand(1)}, Name));
CI->eraseFromParent();
return;
case Intrinsic::x86_sse41_ptestc:
case Intrinsic::x86_sse41_ptestz:
case Intrinsic::x86_sse41_ptestnzc: {
// The arguments for these intrinsics used to be v4f32, and changed
// to v2i64. This is purely a nop, since those are bitwise intrinsics.
// So, the only thing required is a bitcast for both arguments.
// First, check the arguments have the old type.
Value *Arg0 = CI->getArgOperand(0);
if (Arg0->getType() != VectorType::get(Type::getFloatTy(C), 4))
return;
// Old intrinsic, add bitcasts
Value *Arg1 = CI->getArgOperand(1);
Type *NewVecTy = VectorType::get(Type::getInt64Ty(C), 2);
Value *BC0 = Builder.CreateBitCast(Arg0, NewVecTy, "cast");
Value *BC1 = Builder.CreateBitCast(Arg1, NewVecTy, "cast");
CallInst *NewCall = Builder.CreateCall(NewFn, {BC0, BC1}, Name);
CI->replaceAllUsesWith(NewCall);
CI->eraseFromParent();
return;
}
case Intrinsic::x86_sse41_insertps:
case Intrinsic::x86_sse41_dppd:
case Intrinsic::x86_sse41_dpps:
case Intrinsic::x86_sse41_mpsadbw:
case Intrinsic::x86_avx_dp_ps_256:
case Intrinsic::x86_avx2_mpsadbw: {
// Need to truncate the last argument from i32 to i8 -- this argument models
// an inherently 8-bit immediate operand to these x86 instructions.
SmallVector<Value *, 4> Args(CI->arg_operands().begin(),
CI->arg_operands().end());
// Replace the last argument with a trunc.
Args.back() = Builder.CreateTrunc(Args.back(), Type::getInt8Ty(C), "trunc");
CallInst *NewCall = Builder.CreateCall(NewFn, Args);
CI->replaceAllUsesWith(NewCall);
CI->eraseFromParent();
return;
}
#endif // HLSL Change - remove platform intrinsics
}
}
// This tests each Function to determine if it needs upgrading. When we find
// one we are interested in, we then upgrade all calls to reflect the new
// function.
void llvm::UpgradeCallsToIntrinsic(Function* F) {
assert(F && "Illegal attempt to upgrade a non-existent intrinsic.");
// Upgrade the function and check if it is a totaly new function.
Function *NewFn;
if (UpgradeIntrinsicFunction(F, NewFn)) {
// Replace all uses to the old function with the new one if necessary.
for (Value::user_iterator UI = F->user_begin(), UE = F->user_end();
UI != UE;) {
if (CallInst *CI = dyn_cast<CallInst>(*UI++))
UpgradeIntrinsicCall(CI, NewFn);
}
// Remove old function, no longer used, from the module.
F->eraseFromParent();
}
}
void llvm::UpgradeInstWithTBAATag(Instruction *I) {
MDNode *MD = I->getMetadata(LLVMContext::MD_tbaa);
assert(MD && "UpgradeInstWithTBAATag should have a TBAA tag");
// Check if the tag uses struct-path aware TBAA format.
if (isa<MDNode>(MD->getOperand(0)) && MD->getNumOperands() >= 3)
return;
if (MD->getNumOperands() == 3) {
Metadata *Elts[] = {MD->getOperand(0), MD->getOperand(1)};
MDNode *ScalarType = MDNode::get(I->getContext(), Elts);
// Create a MDNode <ScalarType, ScalarType, offset 0, const>
Metadata *Elts2[] = {ScalarType, ScalarType,
ConstantAsMetadata::get(Constant::getNullValue(
Type::getInt64Ty(I->getContext()))),
MD->getOperand(2)};
I->setMetadata(LLVMContext::MD_tbaa, MDNode::get(I->getContext(), Elts2));
} else {
// Create a MDNode <MD, MD, offset 0>
Metadata *Elts[] = {MD, MD, ConstantAsMetadata::get(Constant::getNullValue(
Type::getInt64Ty(I->getContext())))};
I->setMetadata(LLVMContext::MD_tbaa, MDNode::get(I->getContext(), Elts));
}
}
Instruction *llvm::UpgradeBitCastInst(unsigned Opc, Value *V, Type *DestTy,
Instruction *&Temp) {
if (Opc != Instruction::BitCast)
return nullptr;
Temp = nullptr;
Type *SrcTy = V->getType();
if (SrcTy->isPtrOrPtrVectorTy() && DestTy->isPtrOrPtrVectorTy() &&
SrcTy->getPointerAddressSpace() != DestTy->getPointerAddressSpace()) {
LLVMContext &Context = V->getContext();
// We have no information about target data layout, so we assume that
// the maximum pointer size is 64bit.
Type *MidTy = Type::getInt64Ty(Context);
Temp = CastInst::Create(Instruction::PtrToInt, V, MidTy);
return CastInst::Create(Instruction::IntToPtr, Temp, DestTy);
}
return nullptr;
}
Value *llvm::UpgradeBitCastExpr(unsigned Opc, Constant *C, Type *DestTy) {
if (Opc != Instruction::BitCast)
return nullptr;
Type *SrcTy = C->getType();
if (SrcTy->isPtrOrPtrVectorTy() && DestTy->isPtrOrPtrVectorTy() &&
SrcTy->getPointerAddressSpace() != DestTy->getPointerAddressSpace()) {
LLVMContext &Context = C->getContext();
// We have no information about target data layout, so we assume that
// the maximum pointer size is 64bit.
Type *MidTy = Type::getInt64Ty(Context);
return ConstantExpr::getIntToPtr(ConstantExpr::getPtrToInt(C, MidTy),
DestTy);
}
return nullptr;
}
/// Check the debug info version number, if it is out-dated, drop the debug
/// info. Return true if module is modified.
bool llvm::UpgradeDebugInfo(Module &M) {
unsigned Version = getDebugMetadataVersionFromModule(M);
if (Version == DEBUG_METADATA_VERSION)
return false;
bool RetCode = StripDebugInfo(M);
if (RetCode) {
DiagnosticInfoDebugMetadataVersion DiagVersion(M, Version);
M.getContext().diagnose(DiagVersion);
}
return RetCode;
}
void llvm::UpgradeMDStringConstant(std::string &String) {
const std::string OldPrefix = "llvm.vectorizer.";
if (String == "llvm.vectorizer.unroll") {
String = "llvm.loop.interleave.count";
} else if (String.find(OldPrefix) == 0) {
String.replace(0, OldPrefix.size(), "llvm.loop.vectorize.");
}
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/DebugInfo.cpp | //===--- DebugInfo.cpp - Debug Information Helper Classes -----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the helper classes used to build and interpret debug
// information in LLVM IR form.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/DebugInfo.h"
#include "LLVMContextImpl.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DIBuilder.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/GVMaterializer.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Dwarf.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
using namespace llvm::dwarf;
DISubprogram *llvm::getDISubprogram(const MDNode *Scope) {
if (auto *LocalScope = dyn_cast_or_null<DILocalScope>(Scope))
return LocalScope->getSubprogram();
return nullptr;
}
DISubprogram *llvm::getDISubprogram(const Function *F) {
// We look for the first instr that has a debug annotation leading back to F.
for (auto &BB : *F) {
auto Inst = std::find_if(BB.begin(), BB.end(), [](const Instruction &Inst) {
return Inst.getDebugLoc();
});
if (Inst == BB.end())
continue;
DebugLoc DLoc = Inst->getDebugLoc();
const MDNode *Scope = DLoc.getInlinedAtScope();
auto *Subprogram = getDISubprogram(Scope);
return Subprogram->describes(F) ? Subprogram : nullptr;
}
return nullptr;
}
DICompositeTypeBase *llvm::getDICompositeType(DIType *T) {
if (auto *C = dyn_cast_or_null<DICompositeTypeBase>(T))
return C;
if (auto *D = dyn_cast_or_null<DIDerivedTypeBase>(T)) {
// This function is currently used by dragonegg and dragonegg does
// not generate identifier for types, so using an empty map to resolve
// DerivedFrom should be fine.
DITypeIdentifierMap EmptyMap;
return getDICompositeType(D->getBaseType().resolve(EmptyMap));
}
return nullptr;
}
DITypeIdentifierMap
llvm::generateDITypeIdentifierMap(const NamedMDNode *CU_Nodes) {
DITypeIdentifierMap Map;
for (unsigned CUi = 0, CUe = CU_Nodes->getNumOperands(); CUi != CUe; ++CUi) {
auto *CU = cast<DICompileUnit>(CU_Nodes->getOperand(CUi));
DINodeArray Retain = CU->getRetainedTypes();
for (unsigned Ti = 0, Te = Retain.size(); Ti != Te; ++Ti) {
if (!isa<DICompositeType>(Retain[Ti]))
continue;
auto *Ty = cast<DICompositeType>(Retain[Ti]);
if (MDString *TypeId = Ty->getRawIdentifier()) {
// Definition has priority over declaration.
// Try to insert (TypeId, Ty) to Map.
std::pair<DITypeIdentifierMap::iterator, bool> P =
Map.insert(std::make_pair(TypeId, Ty));
// If TypeId already exists in Map and this is a definition, replace
// whatever we had (declaration or definition) with the definition.
if (!P.second && !Ty->isForwardDecl())
P.first->second = Ty;
}
}
}
return Map;
}
//===----------------------------------------------------------------------===//
// DebugInfoFinder implementations.
//===----------------------------------------------------------------------===//
void DebugInfoFinder::reset() {
CUs.clear();
SPs.clear();
GVs.clear();
TYs.clear();
Scopes.clear();
NodesSeen.clear();
TypeIdentifierMap.clear();
TypeMapInitialized = false;
}
void DebugInfoFinder::InitializeTypeMap(const Module &M) {
if (!TypeMapInitialized)
if (NamedMDNode *CU_Nodes = M.getNamedMetadata("llvm.dbg.cu")) {
TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes);
TypeMapInitialized = true;
}
}
void DebugInfoFinder::processModule(const Module &M) {
InitializeTypeMap(M);
if (NamedMDNode *CU_Nodes = M.getNamedMetadata("llvm.dbg.cu")) {
for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
auto *CU = cast<DICompileUnit>(CU_Nodes->getOperand(i));
addCompileUnit(CU);
for (auto *DIG : CU->getGlobalVariables()) {
if (addGlobalVariable(DIG)) {
processScope(DIG->getScope());
processType(DIG->getType().resolve(TypeIdentifierMap));
}
}
for (auto *SP : CU->getSubprograms())
processSubprogram(SP);
for (auto *ET : CU->getEnumTypes())
processType(ET);
for (auto *RT : CU->getRetainedTypes())
processType(RT);
for (auto *Import : CU->getImportedEntities()) {
auto *Entity = Import->getEntity().resolve(TypeIdentifierMap);
if (auto *T = dyn_cast<DIType>(Entity))
processType(T);
else if (auto *SP = dyn_cast<DISubprogram>(Entity))
processSubprogram(SP);
else if (auto *NS = dyn_cast<DINamespace>(Entity))
processScope(NS->getScope());
else if (auto *M = dyn_cast<DIModule>(Entity))
processScope(M->getScope());
}
}
}
}
void DebugInfoFinder::processLocation(const Module &M, const DILocation *Loc) {
if (!Loc)
return;
InitializeTypeMap(M);
processScope(Loc->getScope());
processLocation(M, Loc->getInlinedAt());
}
void DebugInfoFinder::processType(DIType *DT) {
if (!addType(DT))
return;
processScope(DT->getScope().resolve(TypeIdentifierMap));
if (auto *DCT = dyn_cast<DICompositeTypeBase>(DT)) {
processType(DCT->getBaseType().resolve(TypeIdentifierMap));
if (auto *ST = dyn_cast<DISubroutineType>(DCT)) {
for (DITypeRef Ref : ST->getTypeArray())
processType(Ref.resolve(TypeIdentifierMap));
return;
}
for (Metadata *D : DCT->getElements()) {
if (auto *T = dyn_cast<DIType>(D))
processType(T);
else if (auto *SP = dyn_cast<DISubprogram>(D))
processSubprogram(SP);
}
} else if (auto *DDT = dyn_cast<DIDerivedTypeBase>(DT)) {
processType(DDT->getBaseType().resolve(TypeIdentifierMap));
}
}
void DebugInfoFinder::processScope(DIScope *Scope) {
if (!Scope)
return;
if (auto *Ty = dyn_cast<DIType>(Scope)) {
processType(Ty);
return;
}
if (auto *CU = dyn_cast<DICompileUnit>(Scope)) {
addCompileUnit(CU);
return;
}
if (auto *SP = dyn_cast<DISubprogram>(Scope)) {
processSubprogram(SP);
return;
}
if (!addScope(Scope))
return;
if (auto *LB = dyn_cast<DILexicalBlockBase>(Scope)) {
processScope(LB->getScope());
} else if (auto *NS = dyn_cast<DINamespace>(Scope)) {
processScope(NS->getScope());
} else if (auto *M = dyn_cast<DIModule>(Scope)) {
processScope(M->getScope());
}
}
void DebugInfoFinder::processSubprogram(DISubprogram *SP) {
if (!addSubprogram(SP))
return;
processScope(SP->getScope().resolve(TypeIdentifierMap));
processType(SP->getType());
for (auto *Element : SP->getTemplateParams()) {
if (auto *TType = dyn_cast<DITemplateTypeParameter>(Element)) {
processType(TType->getType().resolve(TypeIdentifierMap));
} else if (auto *TVal = dyn_cast<DITemplateValueParameter>(Element)) {
processType(TVal->getType().resolve(TypeIdentifierMap));
}
}
}
void DebugInfoFinder::processDeclare(const Module &M,
const DbgDeclareInst *DDI) {
auto *N = dyn_cast<MDNode>(DDI->getVariable());
if (!N)
return;
InitializeTypeMap(M);
auto *DV = dyn_cast<DILocalVariable>(N);
if (!DV)
return;
if (!NodesSeen.insert(DV).second)
return;
processScope(DV->getScope());
processType(DV->getType().resolve(TypeIdentifierMap));
}
void DebugInfoFinder::processValue(const Module &M, const DbgValueInst *DVI) {
auto *N = dyn_cast<MDNode>(DVI->getVariable());
if (!N)
return;
InitializeTypeMap(M);
auto *DV = dyn_cast<DILocalVariable>(N);
if (!DV)
return;
if (!NodesSeen.insert(DV).second)
return;
processScope(DV->getScope());
processType(DV->getType().resolve(TypeIdentifierMap));
}
bool DebugInfoFinder::addType(DIType *DT) {
if (!DT)
return false;
if (!NodesSeen.insert(DT).second)
return false;
TYs.push_back(const_cast<DIType *>(DT));
return true;
}
bool DebugInfoFinder::addCompileUnit(DICompileUnit *CU) {
if (!CU)
return false;
if (!NodesSeen.insert(CU).second)
return false;
CUs.push_back(CU);
return true;
}
bool DebugInfoFinder::addGlobalVariable(DIGlobalVariable *DIG) {
if (!DIG)
return false;
if (!NodesSeen.insert(DIG).second)
return false;
GVs.push_back(DIG);
return true;
}
// HLSL Change Begins.
bool DebugInfoFinder::appendGlobalVariable(DIGlobalVariable *DIG) {
return addGlobalVariable(DIG);
}
// HLSL Change Ends.
bool DebugInfoFinder::addSubprogram(DISubprogram *SP) {
if (!SP)
return false;
if (!NodesSeen.insert(SP).second)
return false;
SPs.push_back(SP);
return true;
}
bool DebugInfoFinder::addScope(DIScope *Scope) {
if (!Scope)
return false;
// FIXME: Ocaml binding generates a scope with no content, we treat it
// as null for now.
if (Scope->getNumOperands() == 0)
return false;
if (!NodesSeen.insert(Scope).second)
return false;
Scopes.push_back(Scope);
return true;
}
bool llvm::stripDebugInfo(Function &F) {
bool Changed = false;
for (BasicBlock &BB : F) {
for (Instruction &I : BB) {
if (I.getDebugLoc()) {
Changed = true;
I.setDebugLoc(DebugLoc());
}
}
}
return Changed;
}
bool llvm::StripDebugInfo(Module &M) {
bool Changed = false;
// Remove all of the calls to the debugger intrinsics, and remove them from
// the module.
if (Function *Declare = M.getFunction("llvm.dbg.declare")) {
while (!Declare->use_empty()) {
CallInst *CI = cast<CallInst>(Declare->user_back());
CI->eraseFromParent();
}
Declare->eraseFromParent();
Changed = true;
}
if (Function *DbgVal = M.getFunction("llvm.dbg.value")) {
while (!DbgVal->use_empty()) {
CallInst *CI = cast<CallInst>(DbgVal->user_back());
CI->eraseFromParent();
}
DbgVal->eraseFromParent();
Changed = true;
}
for (Module::named_metadata_iterator NMI = M.named_metadata_begin(),
NME = M.named_metadata_end(); NMI != NME;) {
NamedMDNode *NMD = NMI;
++NMI;
if (NMD->getName().startswith("llvm.dbg.")) {
NMD->eraseFromParent();
Changed = true;
}
}
for (Function &F : M)
Changed |= stripDebugInfo(F);
if (GVMaterializer *Materializer = M.getMaterializer())
Materializer->setStripDebugInfo();
return Changed;
}
unsigned llvm::getDebugMetadataVersionFromModule(const Module &M) {
if (auto *Val = mdconst::dyn_extract_or_null<ConstantInt>(
M.getModuleFlag("Debug Info Version")))
return Val->getZExtValue();
return 0;
}
// HLSL Change - begin
bool llvm::hasDebugInfo(const Module &M) {
// We might just get away with checking if there's "llvm.dbg.cu",
// but this is more robust.
for (Module::const_named_metadata_iterator NMI = M.named_metadata_begin(),
NME = M.named_metadata_end();
NMI != NME; ++NMI) {
if (NMI->getName().startswith("llvm.dbg.")) {
return true;
}
}
return false;
}
// HLSL Change - end
DenseMap<const llvm::Function *, DISubprogram *>
llvm::makeSubprogramMap(const Module &M) {
DenseMap<const Function *, DISubprogram *> R;
NamedMDNode *CU_Nodes = M.getNamedMetadata("llvm.dbg.cu");
if (!CU_Nodes)
return R;
for (MDNode *N : CU_Nodes->operands()) {
auto *CUNode = cast<DICompileUnit>(N);
for (auto *SP : CUNode->getSubprograms()) {
if (Function *F = SP->getFunction())
R.insert(std::make_pair(F, SP));
}
}
return R;
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/IRPrintingPasses.cpp | //===--- IRPrintingPasses.cpp - Module and Function printing passes -------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// PrintModulePass and PrintFunctionPass implementations.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/IRPrintingPasses.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/PassManager.h"
#include "llvm/IR/AssemblyAnnotationWriter.h" // HLSL Change
#include "llvm/IR/DebugInfoMetadata.h" // HLSL Change
#include "llvm/IR/IntrinsicInst.h" // HLSL Change
#include "llvm/Support/FormattedStream.h" // HLSL Change
#include "llvm/Pass.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
// HLSL Change - Begin
namespace {
class DxilAAW : public llvm::AssemblyAnnotationWriter {
public:
~DxilAAW() {}
void printInfoComment(const Value &V, formatted_raw_ostream &OS) override {
using namespace llvm;
if (const Instruction *I = dyn_cast<Instruction>(&V)) {
if (isa<DbgInfoIntrinsic>(I)) {
DILocalVariable *Var = nullptr;
DIExpression *Expr = nullptr;
if (const DbgDeclareInst *DI = dyn_cast<DbgDeclareInst>(I)) {
Var = DI->getVariable();
Expr = DI->getExpression();
}
else if (const DbgValueInst *DI = dyn_cast<DbgValueInst>(I)) {
Var = DI->getVariable();
Expr = DI->getExpression();
}
if (Var && Expr) {
OS << " ; var:\"" << Var->getName() << "\"" << " ";
Expr->printAsBody(OS);
}
}
else {
DebugLoc Loc = I->getDebugLoc();
if (Loc && Loc.getLine() != 0)
OS << " ; line:" << Loc.getLine() << " col:" << Loc.getCol();
}
}
}
};
}
// HLSL Change - End
PrintModulePass::PrintModulePass() : OS(dbgs()) {}
PrintModulePass::PrintModulePass(raw_ostream &OS, const std::string &Banner,
bool ShouldPreserveUseListOrder)
: OS(OS), Banner(Banner),
ShouldPreserveUseListOrder(ShouldPreserveUseListOrder) {}
PreservedAnalyses PrintModulePass::run(Module &M) {
DxilAAW AAW; // HLSL Change
OS << Banner;
M.print(OS, &AAW, ShouldPreserveUseListOrder); // HLSL Change
return PreservedAnalyses::all();
}
PrintFunctionPass::PrintFunctionPass() : OS(dbgs()) {}
PrintFunctionPass::PrintFunctionPass(raw_ostream &OS, const std::string &Banner)
: OS(OS), Banner(Banner) {}
PreservedAnalyses PrintFunctionPass::run(Function &F) {
OS << Banner << static_cast<Value &>(F);
return PreservedAnalyses::all();
}
namespace {
class PrintModulePassWrapper : public ModulePass {
PrintModulePass P;
public:
static char ID;
PrintModulePassWrapper() : ModulePass(ID) {}
PrintModulePassWrapper(raw_ostream &OS, const std::string &Banner,
bool ShouldPreserveUseListOrder)
: ModulePass(ID), P(OS, Banner, ShouldPreserveUseListOrder) {}
bool runOnModule(Module &M) override {
P.run(M);
return false;
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.setPreservesAll();
}
};
class PrintFunctionPassWrapper : public FunctionPass {
PrintFunctionPass P;
public:
static char ID;
PrintFunctionPassWrapper() : FunctionPass(ID) {}
PrintFunctionPassWrapper(raw_ostream &OS, const std::string &Banner)
: FunctionPass(ID), P(OS, Banner) {}
// This pass just prints a banner followed by the function as it's processed.
bool runOnFunction(Function &F) override {
P.run(F);
return false;
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.setPreservesAll();
}
};
class PrintBasicBlockPass : public BasicBlockPass {
raw_ostream &Out;
std::string Banner;
public:
static char ID;
PrintBasicBlockPass() : BasicBlockPass(ID), Out(dbgs()) {}
PrintBasicBlockPass(raw_ostream &Out, const std::string &Banner)
: BasicBlockPass(ID), Out(Out), Banner(Banner) {}
bool runOnBasicBlock(BasicBlock &BB) override {
Out << Banner << BB;
return false;
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.setPreservesAll();
}
};
}
char PrintModulePassWrapper::ID = 0;
INITIALIZE_PASS(PrintModulePassWrapper, "print-module",
"Print module to stderr", false, false)
char PrintFunctionPassWrapper::ID = 0;
INITIALIZE_PASS(PrintFunctionPassWrapper, "print-function",
"Print function to stderr", false, false)
char PrintBasicBlockPass::ID = 0;
INITIALIZE_PASS(PrintBasicBlockPass, "print-bb", "Print BB to stderr", false,
false)
ModulePass *llvm::createPrintModulePass(llvm::raw_ostream &OS,
const std::string &Banner,
bool ShouldPreserveUseListOrder) {
return new PrintModulePassWrapper(OS, Banner, ShouldPreserveUseListOrder);
}
FunctionPass *llvm::createPrintFunctionPass(llvm::raw_ostream &OS,
const std::string &Banner) {
return new PrintFunctionPassWrapper(OS, Banner);
}
BasicBlockPass *llvm::createPrintBasicBlockPass(llvm::raw_ostream &OS,
const std::string &Banner) {
return new PrintBasicBlockPass(OS, Banner);
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/Operator.cpp |
#include "llvm/IR/Operator.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Type.h"
#include "ConstantsContext.h"
namespace llvm {
Type *GEPOperator::getSourceElementType() const {
if (auto *I = dyn_cast<GetElementPtrInst>(this))
return I->getSourceElementType();
return cast<GetElementPtrConstantExpr>(this)->getSourceElementType();
}
bool GEPOperator::accumulateConstantOffset(const DataLayout &DL,
APInt &Offset) const {
assert(Offset.getBitWidth() ==
DL.getPointerSizeInBits(getPointerAddressSpace()) &&
"The offset must have exactly as many bits as our pointer.");
for (gep_type_iterator GTI = gep_type_begin(this), GTE = gep_type_end(this);
GTI != GTE; ++GTI) {
ConstantInt *OpC = dyn_cast<ConstantInt>(GTI.getOperand());
if (!OpC)
return false;
if (OpC->isZero())
continue;
// Handle a struct index, which adds its field offset to the pointer.
if (StructType *STy = dyn_cast<StructType>(*GTI)) {
unsigned ElementIdx = OpC->getZExtValue();
const StructLayout *SL = DL.getStructLayout(STy);
Offset += APInt(Offset.getBitWidth(), SL->getElementOffset(ElementIdx));
continue;
}
// For array or vector indices, scale the index by the size of the type.
APInt Index = OpC->getValue().sextOrTrunc(Offset.getBitWidth());
Offset += Index * APInt(Offset.getBitWidth(),
DL.getTypeAllocSize(GTI.getIndexedType()));
}
return true;
}
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/ConstantRange.cpp | //===-- ConstantRange.cpp - ConstantRange implementation ------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Represent a range of possible values that may occur when the program is run
// for an integral value. This keeps track of a lower and upper bound for the
// constant, which MAY wrap around the end of the numeric range. To do this, it
// keeps track of a [lower, upper) bound, which specifies an interval just like
// STL iterators. When used with boolean values, the following are important
// ranges (other integral ranges use min/max values for special range values):
//
// [F, F) = {} = Empty set
// [T, F) = {T}
// [F, T) = {F}
// [T, T) = {F, T} = Full set
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/InstrTypes.h"
#include "llvm/IR/ConstantRange.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
/// Initialize a full (the default) or empty set for the specified type.
///
ConstantRange::ConstantRange(uint32_t BitWidth, bool Full) {
if (Full)
Lower = Upper = APInt::getMaxValue(BitWidth);
else
Lower = Upper = APInt::getMinValue(BitWidth);
}
/// Initialize a range to hold the single specified value.
///
ConstantRange::ConstantRange(APIntMoveTy V)
: Lower(std::move(V)), Upper(Lower + 1) {}
ConstantRange::ConstantRange(APIntMoveTy L, APIntMoveTy U)
: Lower(std::move(L)), Upper(std::move(U)) {
assert(Lower.getBitWidth() == Upper.getBitWidth() &&
"ConstantRange with unequal bit widths");
assert((Lower != Upper || (Lower.isMaxValue() || Lower.isMinValue())) &&
"Lower == Upper, but they aren't min or max value!");
}
ConstantRange ConstantRange::makeAllowedICmpRegion(CmpInst::Predicate Pred,
const ConstantRange &CR) {
if (CR.isEmptySet())
return CR;
uint32_t W = CR.getBitWidth();
switch (Pred) {
default:
llvm_unreachable("Invalid ICmp predicate to makeAllowedICmpRegion()");
case CmpInst::ICMP_EQ:
return CR;
case CmpInst::ICMP_NE:
if (CR.isSingleElement())
return ConstantRange(CR.getUpper(), CR.getLower());
return ConstantRange(W);
case CmpInst::ICMP_ULT: {
APInt UMax(CR.getUnsignedMax());
if (UMax.isMinValue())
return ConstantRange(W, /* empty */ false);
return ConstantRange(APInt::getMinValue(W), UMax);
}
case CmpInst::ICMP_SLT: {
APInt SMax(CR.getSignedMax());
if (SMax.isMinSignedValue())
return ConstantRange(W, /* empty */ false);
return ConstantRange(APInt::getSignedMinValue(W), SMax);
}
case CmpInst::ICMP_ULE: {
APInt UMax(CR.getUnsignedMax());
if (UMax.isMaxValue())
return ConstantRange(W);
return ConstantRange(APInt::getMinValue(W), UMax + 1);
}
case CmpInst::ICMP_SLE: {
APInt SMax(CR.getSignedMax());
if (SMax.isMaxSignedValue())
return ConstantRange(W);
return ConstantRange(APInt::getSignedMinValue(W), SMax + 1);
}
case CmpInst::ICMP_UGT: {
APInt UMin(CR.getUnsignedMin());
if (UMin.isMaxValue())
return ConstantRange(W, /* empty */ false);
return ConstantRange(UMin + 1, APInt::getNullValue(W));
}
case CmpInst::ICMP_SGT: {
APInt SMin(CR.getSignedMin());
if (SMin.isMaxSignedValue())
return ConstantRange(W, /* empty */ false);
return ConstantRange(SMin + 1, APInt::getSignedMinValue(W));
}
case CmpInst::ICMP_UGE: {
APInt UMin(CR.getUnsignedMin());
if (UMin.isMinValue())
return ConstantRange(W);
return ConstantRange(UMin, APInt::getNullValue(W));
}
case CmpInst::ICMP_SGE: {
APInt SMin(CR.getSignedMin());
if (SMin.isMinSignedValue())
return ConstantRange(W);
return ConstantRange(SMin, APInt::getSignedMinValue(W));
}
}
}
ConstantRange ConstantRange::makeSatisfyingICmpRegion(CmpInst::Predicate Pred,
const ConstantRange &CR) {
// Follows from De-Morgan's laws:
//
// ~(~A union ~B) == A intersect B.
//
return makeAllowedICmpRegion(CmpInst::getInversePredicate(Pred), CR)
.inverse();
}
/// isFullSet - Return true if this set contains all of the elements possible
/// for this data-type
bool ConstantRange::isFullSet() const {
return Lower == Upper && Lower.isMaxValue();
}
/// isEmptySet - Return true if this set contains no members.
///
bool ConstantRange::isEmptySet() const {
return Lower == Upper && Lower.isMinValue();
}
/// isWrappedSet - Return true if this set wraps around the top of the range,
/// for example: [100, 8)
///
bool ConstantRange::isWrappedSet() const {
return Lower.ugt(Upper);
}
/// isSignWrappedSet - Return true if this set wraps around the INT_MIN of
/// its bitwidth, for example: i8 [120, 140).
///
bool ConstantRange::isSignWrappedSet() const {
return contains(APInt::getSignedMaxValue(getBitWidth())) &&
contains(APInt::getSignedMinValue(getBitWidth()));
}
/// getSetSize - Return the number of elements in this set.
///
APInt ConstantRange::getSetSize() const {
if (isFullSet()) {
APInt Size(getBitWidth()+1, 0);
Size.setBit(getBitWidth());
return Size;
}
// This is also correct for wrapped sets.
return (Upper - Lower).zext(getBitWidth()+1);
}
/// getUnsignedMax - Return the largest unsigned value contained in the
/// ConstantRange.
///
APInt ConstantRange::getUnsignedMax() const {
if (isFullSet() || isWrappedSet())
return APInt::getMaxValue(getBitWidth());
return getUpper() - 1;
}
/// getUnsignedMin - Return the smallest unsigned value contained in the
/// ConstantRange.
///
APInt ConstantRange::getUnsignedMin() const {
if (isFullSet() || (isWrappedSet() && getUpper() != 0))
return APInt::getMinValue(getBitWidth());
return getLower();
}
/// getSignedMax - Return the largest signed value contained in the
/// ConstantRange.
///
APInt ConstantRange::getSignedMax() const {
APInt SignedMax(APInt::getSignedMaxValue(getBitWidth()));
if (!isWrappedSet()) {
if (getLower().sle(getUpper() - 1))
return getUpper() - 1;
return SignedMax;
}
if (getLower().isNegative() == getUpper().isNegative())
return SignedMax;
return getUpper() - 1;
}
/// getSignedMin - Return the smallest signed value contained in the
/// ConstantRange.
///
APInt ConstantRange::getSignedMin() const {
APInt SignedMin(APInt::getSignedMinValue(getBitWidth()));
if (!isWrappedSet()) {
if (getLower().sle(getUpper() - 1))
return getLower();
return SignedMin;
}
if ((getUpper() - 1).slt(getLower())) {
if (getUpper() != SignedMin)
return SignedMin;
}
return getLower();
}
/// contains - Return true if the specified value is in the set.
///
bool ConstantRange::contains(const APInt &V) const {
if (Lower == Upper)
return isFullSet();
if (!isWrappedSet())
return Lower.ule(V) && V.ult(Upper);
return Lower.ule(V) || V.ult(Upper);
}
/// contains - Return true if the argument is a subset of this range.
/// Two equal sets contain each other. The empty set contained by all other
/// sets.
///
bool ConstantRange::contains(const ConstantRange &Other) const {
if (isFullSet() || Other.isEmptySet()) return true;
if (isEmptySet() || Other.isFullSet()) return false;
if (!isWrappedSet()) {
if (Other.isWrappedSet())
return false;
return Lower.ule(Other.getLower()) && Other.getUpper().ule(Upper);
}
if (!Other.isWrappedSet())
return Other.getUpper().ule(Upper) ||
Lower.ule(Other.getLower());
return Other.getUpper().ule(Upper) && Lower.ule(Other.getLower());
}
/// subtract - Subtract the specified constant from the endpoints of this
/// constant range.
ConstantRange ConstantRange::subtract(const APInt &Val) const {
assert(Val.getBitWidth() == getBitWidth() && "Wrong bit width");
// If the set is empty or full, don't modify the endpoints.
if (Lower == Upper)
return *this;
return ConstantRange(Lower - Val, Upper - Val);
}
/// \brief Subtract the specified range from this range (aka relative complement
/// of the sets).
ConstantRange ConstantRange::difference(const ConstantRange &CR) const {
return intersectWith(CR.inverse());
}
/// intersectWith - Return the range that results from the intersection of this
/// range with another range. The resultant range is guaranteed to include all
/// elements contained in both input ranges, and to have the smallest possible
/// set size that does so. Because there may be two intersections with the
/// same set size, A.intersectWith(B) might not be equal to B.intersectWith(A).
ConstantRange ConstantRange::intersectWith(const ConstantRange &CR) const {
assert(getBitWidth() == CR.getBitWidth() &&
"ConstantRange types don't agree!");
// Handle common cases.
if ( isEmptySet() || CR.isFullSet()) return *this;
if (CR.isEmptySet() || isFullSet()) return CR;
if (!isWrappedSet() && CR.isWrappedSet())
return CR.intersectWith(*this);
if (!isWrappedSet() && !CR.isWrappedSet()) {
if (Lower.ult(CR.Lower)) {
if (Upper.ule(CR.Lower))
return ConstantRange(getBitWidth(), false);
if (Upper.ult(CR.Upper))
return ConstantRange(CR.Lower, Upper);
return CR;
}
if (Upper.ult(CR.Upper))
return *this;
if (Lower.ult(CR.Upper))
return ConstantRange(Lower, CR.Upper);
return ConstantRange(getBitWidth(), false);
}
if (isWrappedSet() && !CR.isWrappedSet()) {
if (CR.Lower.ult(Upper)) {
if (CR.Upper.ult(Upper))
return CR;
if (CR.Upper.ule(Lower))
return ConstantRange(CR.Lower, Upper);
if (getSetSize().ult(CR.getSetSize()))
return *this;
return CR;
}
if (CR.Lower.ult(Lower)) {
if (CR.Upper.ule(Lower))
return ConstantRange(getBitWidth(), false);
return ConstantRange(Lower, CR.Upper);
}
return CR;
}
if (CR.Upper.ult(Upper)) {
if (CR.Lower.ult(Upper)) {
if (getSetSize().ult(CR.getSetSize()))
return *this;
return CR;
}
if (CR.Lower.ult(Lower))
return ConstantRange(Lower, CR.Upper);
return CR;
}
if (CR.Upper.ule(Lower)) {
if (CR.Lower.ult(Lower))
return *this;
return ConstantRange(CR.Lower, Upper);
}
if (getSetSize().ult(CR.getSetSize()))
return *this;
return CR;
}
/// unionWith - Return the range that results from the union of this range with
/// another range. The resultant range is guaranteed to include the elements of
/// both sets, but may contain more. For example, [3, 9) union [12,15) is
/// [3, 15), which includes 9, 10, and 11, which were not included in either
/// set before.
///
ConstantRange ConstantRange::unionWith(const ConstantRange &CR) const {
assert(getBitWidth() == CR.getBitWidth() &&
"ConstantRange types don't agree!");
if ( isFullSet() || CR.isEmptySet()) return *this;
if (CR.isFullSet() || isEmptySet()) return CR;
if (!isWrappedSet() && CR.isWrappedSet()) return CR.unionWith(*this);
if (!isWrappedSet() && !CR.isWrappedSet()) {
if (CR.Upper.ult(Lower) || Upper.ult(CR.Lower)) {
// If the two ranges are disjoint, find the smaller gap and bridge it.
APInt d1 = CR.Lower - Upper, d2 = Lower - CR.Upper;
if (d1.ult(d2))
return ConstantRange(Lower, CR.Upper);
return ConstantRange(CR.Lower, Upper);
}
APInt L = Lower, U = Upper;
if (CR.Lower.ult(L))
L = CR.Lower;
if ((CR.Upper - 1).ugt(U - 1))
U = CR.Upper;
if (L == 0 && U == 0)
return ConstantRange(getBitWidth());
return ConstantRange(L, U);
}
if (!CR.isWrappedSet()) {
// ------U L----- and ------U L----- : this
// L--U L--U : CR
if (CR.Upper.ule(Upper) || CR.Lower.uge(Lower))
return *this;
// ------U L----- : this
// L---------U : CR
if (CR.Lower.ule(Upper) && Lower.ule(CR.Upper))
return ConstantRange(getBitWidth());
// ----U L---- : this
// L---U : CR
// <d1> <d2>
if (Upper.ule(CR.Lower) && CR.Upper.ule(Lower)) {
APInt d1 = CR.Lower - Upper, d2 = Lower - CR.Upper;
if (d1.ult(d2))
return ConstantRange(Lower, CR.Upper);
return ConstantRange(CR.Lower, Upper);
}
// ----U L----- : this
// L----U : CR
if (Upper.ult(CR.Lower) && Lower.ult(CR.Upper))
return ConstantRange(CR.Lower, Upper);
// ------U L---- : this
// L-----U : CR
assert(CR.Lower.ult(Upper) && CR.Upper.ult(Lower) &&
"ConstantRange::unionWith missed a case with one range wrapped");
return ConstantRange(Lower, CR.Upper);
}
// ------U L---- and ------U L---- : this
// -U L----------- and ------------U L : CR
if (CR.Lower.ule(Upper) || Lower.ule(CR.Upper))
return ConstantRange(getBitWidth());
APInt L = Lower, U = Upper;
if (CR.Upper.ugt(U))
U = CR.Upper;
if (CR.Lower.ult(L))
L = CR.Lower;
return ConstantRange(L, U);
}
/// zeroExtend - Return a new range in the specified integer type, which must
/// be strictly larger than the current type. The returned range will
/// correspond to the possible range of values as if the source range had been
/// zero extended.
ConstantRange ConstantRange::zeroExtend(uint32_t DstTySize) const {
if (isEmptySet()) return ConstantRange(DstTySize, /*isFullSet=*/false);
unsigned SrcTySize = getBitWidth();
assert(SrcTySize < DstTySize && "Not a value extension");
if (isFullSet() || isWrappedSet()) {
// Change into [0, 1 << src bit width)
APInt LowerExt(DstTySize, 0);
if (!Upper) // special case: [X, 0) -- not really wrapping around
LowerExt = Lower.zext(DstTySize);
return ConstantRange(LowerExt, APInt::getOneBitSet(DstTySize, SrcTySize));
}
return ConstantRange(Lower.zext(DstTySize), Upper.zext(DstTySize));
}
/// signExtend - Return a new range in the specified integer type, which must
/// be strictly larger than the current type. The returned range will
/// correspond to the possible range of values as if the source range had been
/// sign extended.
ConstantRange ConstantRange::signExtend(uint32_t DstTySize) const {
if (isEmptySet()) return ConstantRange(DstTySize, /*isFullSet=*/false);
unsigned SrcTySize = getBitWidth();
assert(SrcTySize < DstTySize && "Not a value extension");
// special case: [X, INT_MIN) -- not really wrapping around
if (Upper.isMinSignedValue())
return ConstantRange(Lower.sext(DstTySize), Upper.zext(DstTySize));
if (isFullSet() || isSignWrappedSet()) {
return ConstantRange(APInt::getHighBitsSet(DstTySize,DstTySize-SrcTySize+1),
APInt::getLowBitsSet(DstTySize, SrcTySize-1) + 1);
}
return ConstantRange(Lower.sext(DstTySize), Upper.sext(DstTySize));
}
/// truncate - Return a new range in the specified integer type, which must be
/// strictly smaller than the current type. The returned range will
/// correspond to the possible range of values as if the source range had been
/// truncated to the specified type.
ConstantRange ConstantRange::truncate(uint32_t DstTySize) const {
assert(getBitWidth() > DstTySize && "Not a value truncation");
if (isEmptySet())
return ConstantRange(DstTySize, /*isFullSet=*/false);
if (isFullSet())
return ConstantRange(DstTySize, /*isFullSet=*/true);
APInt MaxValue = APInt::getMaxValue(DstTySize).zext(getBitWidth());
APInt MaxBitValue(getBitWidth(), 0);
MaxBitValue.setBit(DstTySize);
APInt LowerDiv(Lower), UpperDiv(Upper);
ConstantRange Union(DstTySize, /*isFullSet=*/false);
// Analyze wrapped sets in their two parts: [0, Upper) \/ [Lower, MaxValue]
// We use the non-wrapped set code to analyze the [Lower, MaxValue) part, and
// then we do the union with [MaxValue, Upper)
if (isWrappedSet()) {
// if Upper is greater than Max Value, it covers the whole truncated range.
if (Upper.uge(MaxValue))
return ConstantRange(DstTySize, /*isFullSet=*/true);
Union = ConstantRange(APInt::getMaxValue(DstTySize),Upper.trunc(DstTySize));
UpperDiv = APInt::getMaxValue(getBitWidth());
// Union covers the MaxValue case, so return if the remaining range is just
// MaxValue.
if (LowerDiv == UpperDiv)
return Union;
}
// Chop off the most significant bits that are past the destination bitwidth.
if (LowerDiv.uge(MaxValue)) {
APInt Div(getBitWidth(), 0);
APInt::udivrem(LowerDiv, MaxBitValue, Div, LowerDiv);
UpperDiv = UpperDiv - MaxBitValue * Div;
}
if (UpperDiv.ule(MaxValue))
return ConstantRange(LowerDiv.trunc(DstTySize),
UpperDiv.trunc(DstTySize)).unionWith(Union);
// The truncated value wrapps around. Check if we can do better than fullset.
APInt UpperModulo = UpperDiv - MaxBitValue;
if (UpperModulo.ult(LowerDiv))
return ConstantRange(LowerDiv.trunc(DstTySize),
UpperModulo.trunc(DstTySize)).unionWith(Union);
return ConstantRange(DstTySize, /*isFullSet=*/true);
}
/// zextOrTrunc - make this range have the bit width given by \p DstTySize. The
/// value is zero extended, truncated, or left alone to make it that width.
ConstantRange ConstantRange::zextOrTrunc(uint32_t DstTySize) const {
unsigned SrcTySize = getBitWidth();
if (SrcTySize > DstTySize)
return truncate(DstTySize);
if (SrcTySize < DstTySize)
return zeroExtend(DstTySize);
return *this;
}
/// sextOrTrunc - make this range have the bit width given by \p DstTySize. The
/// value is sign extended, truncated, or left alone to make it that width.
ConstantRange ConstantRange::sextOrTrunc(uint32_t DstTySize) const {
unsigned SrcTySize = getBitWidth();
if (SrcTySize > DstTySize)
return truncate(DstTySize);
if (SrcTySize < DstTySize)
return signExtend(DstTySize);
return *this;
}
ConstantRange
ConstantRange::add(const ConstantRange &Other) const {
if (isEmptySet() || Other.isEmptySet())
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
if (isFullSet() || Other.isFullSet())
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
APInt Spread_X = getSetSize(), Spread_Y = Other.getSetSize();
APInt NewLower = getLower() + Other.getLower();
APInt NewUpper = getUpper() + Other.getUpper() - 1;
if (NewLower == NewUpper)
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
ConstantRange X = ConstantRange(NewLower, NewUpper);
if (X.getSetSize().ult(Spread_X) || X.getSetSize().ult(Spread_Y))
// We've wrapped, therefore, full set.
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
return X;
}
ConstantRange
ConstantRange::sub(const ConstantRange &Other) const {
if (isEmptySet() || Other.isEmptySet())
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
if (isFullSet() || Other.isFullSet())
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
APInt Spread_X = getSetSize(), Spread_Y = Other.getSetSize();
APInt NewLower = getLower() - Other.getUpper() + 1;
APInt NewUpper = getUpper() - Other.getLower();
if (NewLower == NewUpper)
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
ConstantRange X = ConstantRange(NewLower, NewUpper);
if (X.getSetSize().ult(Spread_X) || X.getSetSize().ult(Spread_Y))
// We've wrapped, therefore, full set.
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
return X;
}
ConstantRange
ConstantRange::multiply(const ConstantRange &Other) const {
// TODO: If either operand is a single element and the multiply is known to
// be non-wrapping, round the result min and max value to the appropriate
// multiple of that element. If wrapping is possible, at least adjust the
// range according to the greatest power-of-two factor of the single element.
if (isEmptySet() || Other.isEmptySet())
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
// Multiplication is signedness-independent. However different ranges can be
// obtained depending on how the input ranges are treated. These different
// ranges are all conservatively correct, but one might be better than the
// other. We calculate two ranges; one treating the inputs as unsigned
// and the other signed, then return the smallest of these ranges.
// Unsigned range first.
APInt this_min = getUnsignedMin().zext(getBitWidth() * 2);
APInt this_max = getUnsignedMax().zext(getBitWidth() * 2);
APInt Other_min = Other.getUnsignedMin().zext(getBitWidth() * 2);
APInt Other_max = Other.getUnsignedMax().zext(getBitWidth() * 2);
ConstantRange Result_zext = ConstantRange(this_min * Other_min,
this_max * Other_max + 1);
ConstantRange UR = Result_zext.truncate(getBitWidth());
// Now the signed range. Because we could be dealing with negative numbers
// here, the lower bound is the smallest of the cartesian product of the
// lower and upper ranges; for example:
// [-1,4) * [-2,3) = min(-1*-2, -1*2, 3*-2, 3*2) = -6.
// Similarly for the upper bound, swapping min for max.
this_min = getSignedMin().sext(getBitWidth() * 2);
this_max = getSignedMax().sext(getBitWidth() * 2);
Other_min = Other.getSignedMin().sext(getBitWidth() * 2);
Other_max = Other.getSignedMax().sext(getBitWidth() * 2);
auto L = {this_min * Other_min, this_min * Other_max,
this_max * Other_min, this_max * Other_max};
auto Compare = [](const APInt &A, const APInt &B) { return A.slt(B); };
ConstantRange Result_sext(std::min(L, Compare), std::max(L, Compare) + 1);
ConstantRange SR = Result_sext.truncate(getBitWidth());
return UR.getSetSize().ult(SR.getSetSize()) ? UR : SR;
}
ConstantRange
ConstantRange::smax(const ConstantRange &Other) const {
// X smax Y is: range(smax(X_smin, Y_smin),
// smax(X_smax, Y_smax))
if (isEmptySet() || Other.isEmptySet())
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
APInt NewL = APIntOps::smax(getSignedMin(), Other.getSignedMin());
APInt NewU = APIntOps::smax(getSignedMax(), Other.getSignedMax()) + 1;
if (NewU == NewL)
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
return ConstantRange(NewL, NewU);
}
ConstantRange
ConstantRange::umax(const ConstantRange &Other) const {
// X umax Y is: range(umax(X_umin, Y_umin),
// umax(X_umax, Y_umax))
if (isEmptySet() || Other.isEmptySet())
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
APInt NewL = APIntOps::umax(getUnsignedMin(), Other.getUnsignedMin());
APInt NewU = APIntOps::umax(getUnsignedMax(), Other.getUnsignedMax()) + 1;
if (NewU == NewL)
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
return ConstantRange(NewL, NewU);
}
ConstantRange
ConstantRange::udiv(const ConstantRange &RHS) const {
if (isEmptySet() || RHS.isEmptySet() || RHS.getUnsignedMax() == 0)
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
if (RHS.isFullSet())
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
APInt Lower = getUnsignedMin().udiv(RHS.getUnsignedMax());
APInt RHS_umin = RHS.getUnsignedMin();
if (RHS_umin == 0) {
// We want the lowest value in RHS excluding zero. Usually that would be 1
// except for a range in the form of [X, 1) in which case it would be X.
if (RHS.getUpper() == 1)
RHS_umin = RHS.getLower();
else
RHS_umin = APInt(getBitWidth(), 1);
}
APInt Upper = getUnsignedMax().udiv(RHS_umin) + 1;
// If the LHS is Full and the RHS is a wrapped interval containing 1 then
// this could occur.
if (Lower == Upper)
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
return ConstantRange(Lower, Upper);
}
ConstantRange
ConstantRange::binaryAnd(const ConstantRange &Other) const {
if (isEmptySet() || Other.isEmptySet())
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
// TODO: replace this with something less conservative
APInt umin = APIntOps::umin(Other.getUnsignedMax(), getUnsignedMax());
if (umin.isAllOnesValue())
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
return ConstantRange(APInt::getNullValue(getBitWidth()), umin + 1);
}
ConstantRange
ConstantRange::binaryOr(const ConstantRange &Other) const {
if (isEmptySet() || Other.isEmptySet())
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
// TODO: replace this with something less conservative
APInt umax = APIntOps::umax(getUnsignedMin(), Other.getUnsignedMin());
if (umax.isMinValue())
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
return ConstantRange(umax, APInt::getNullValue(getBitWidth()));
}
ConstantRange
ConstantRange::shl(const ConstantRange &Other) const {
if (isEmptySet() || Other.isEmptySet())
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
APInt min = getUnsignedMin().shl(Other.getUnsignedMin());
APInt max = getUnsignedMax().shl(Other.getUnsignedMax());
// there's no overflow!
APInt Zeros(getBitWidth(), getUnsignedMax().countLeadingZeros());
if (Zeros.ugt(Other.getUnsignedMax()))
return ConstantRange(min, max + 1);
// FIXME: implement the other tricky cases
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
}
ConstantRange
ConstantRange::lshr(const ConstantRange &Other) const {
if (isEmptySet() || Other.isEmptySet())
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
APInt max = getUnsignedMax().lshr(Other.getUnsignedMin());
APInt min = getUnsignedMin().lshr(Other.getUnsignedMax());
if (min == max + 1)
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
return ConstantRange(min, max + 1);
}
ConstantRange ConstantRange::inverse() const {
if (isFullSet())
return ConstantRange(getBitWidth(), /*isFullSet=*/false);
if (isEmptySet())
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
return ConstantRange(Upper, Lower);
}
/// print - Print out the bounds to a stream...
///
void ConstantRange::print(raw_ostream &OS) const {
if (isFullSet())
OS << "full-set";
else if (isEmptySet())
OS << "empty-set";
else
OS << "[" << Lower << "," << Upper << ")";
}
/// dump - Allow printing from a debugger easily...
///
void ConstantRange::dump() const {
print(dbgs());
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/Globals.cpp | //===-- Globals.cpp - Implement the GlobalValue & GlobalVariable class ----===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the GlobalValue & GlobalVariable classes for the IR
// library.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/GlobalValue.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Operator.h"
#include "llvm/Support/ErrorHandling.h"
using namespace llvm;
//===----------------------------------------------------------------------===//
// GlobalValue Class
//===----------------------------------------------------------------------===//
bool GlobalValue::isMaterializable() const {
if (const Function *F = dyn_cast<Function>(this))
return F->isMaterializable();
return false;
}
bool GlobalValue::isDematerializable() const {
return getParent() && getParent()->isDematerializable(this);
}
std::error_code GlobalValue::materialize() {
return getParent()->materialize(this);
}
void GlobalValue::dematerialize() {
getParent()->dematerialize(this);
}
/// Override destroyConstantImpl to make sure it doesn't get called on
/// GlobalValue's because they shouldn't be treated like other constants.
void GlobalValue::destroyConstantImpl() {
llvm_unreachable("You can't GV->destroyConstantImpl()!");
}
Value *GlobalValue::handleOperandChangeImpl(Value *From, Value *To, Use *U) {
llvm_unreachable("Unsupported class for handleOperandChange()!");
}
/// copyAttributesFrom - copy all additional attributes (those not needed to
/// create a GlobalValue) from the GlobalValue Src to this one.
void GlobalValue::copyAttributesFrom(const GlobalValue *Src) {
setVisibility(Src->getVisibility());
setUnnamedAddr(Src->hasUnnamedAddr());
setDLLStorageClass(Src->getDLLStorageClass());
}
unsigned GlobalValue::getAlignment() const {
if (auto *GA = dyn_cast<GlobalAlias>(this)) {
// In general we cannot compute this at the IR level, but we try.
if (const GlobalObject *GO = GA->getBaseObject())
return GO->getAlignment();
// FIXME: we should also be able to handle:
// Alias = Global + Offset
// Alias = Absolute
return 0;
}
return cast<GlobalObject>(this)->getAlignment();
}
void GlobalObject::setAlignment(unsigned Align) {
assert((Align & (Align-1)) == 0 && "Alignment is not a power of 2!");
assert(Align <= MaximumAlignment &&
"Alignment is greater than MaximumAlignment!");
unsigned AlignmentData = Log2_32(Align) + 1;
unsigned OldData = getGlobalValueSubClassData();
setGlobalValueSubClassData((OldData & ~AlignmentMask) | AlignmentData);
assert(getAlignment() == Align && "Alignment representation error!");
}
unsigned GlobalObject::getGlobalObjectSubClassData() const {
unsigned ValueData = getGlobalValueSubClassData();
return ValueData >> AlignmentBits;
}
void GlobalObject::setGlobalObjectSubClassData(unsigned Val) {
unsigned OldData = getGlobalValueSubClassData();
setGlobalValueSubClassData((OldData & AlignmentMask) |
(Val << AlignmentBits));
assert(getGlobalObjectSubClassData() == Val && "representation error");
}
void GlobalObject::copyAttributesFrom(const GlobalValue *Src) {
const auto *GV = cast<GlobalObject>(Src);
GlobalValue::copyAttributesFrom(GV);
setAlignment(GV->getAlignment());
setSection(GV->getSection());
}
const char *GlobalValue::getSection() const {
if (auto *GA = dyn_cast<GlobalAlias>(this)) {
// In general we cannot compute this at the IR level, but we try.
if (const GlobalObject *GO = GA->getBaseObject())
return GO->getSection();
return "";
}
return cast<GlobalObject>(this)->getSection();
}
Comdat *GlobalValue::getComdat() {
if (auto *GA = dyn_cast<GlobalAlias>(this)) {
// In general we cannot compute this at the IR level, but we try.
if (const GlobalObject *GO = GA->getBaseObject())
return const_cast<GlobalObject *>(GO)->getComdat();
return nullptr;
}
return cast<GlobalObject>(this)->getComdat();
}
void GlobalObject::setSection(StringRef S) { Section = S; }
bool GlobalValue::isDeclaration() const {
// Globals are definitions if they have an initializer.
if (const GlobalVariable *GV = dyn_cast<GlobalVariable>(this))
return GV->getNumOperands() == 0;
// Functions are definitions if they have a body.
if (const Function *F = dyn_cast<Function>(this))
return F->empty() && !F->isMaterializable();
// Aliases are always definitions.
assert(isa<GlobalAlias>(this));
return false;
}
//===----------------------------------------------------------------------===//
// GlobalVariable Implementation
//===----------------------------------------------------------------------===//
GlobalVariable::GlobalVariable(Type *Ty, bool constant, LinkageTypes Link,
Constant *InitVal, const Twine &Name,
ThreadLocalMode TLMode, unsigned AddressSpace,
bool isExternallyInitialized)
: GlobalObject(PointerType::get(Ty, AddressSpace), Value::GlobalVariableVal,
OperandTraits<GlobalVariable>::op_begin(this),
InitVal != nullptr, Link, Name),
isConstantGlobal(constant),
isExternallyInitializedConstant(isExternallyInitialized) {
setThreadLocalMode(TLMode);
if (InitVal) {
assert(InitVal->getType() == Ty &&
"Initializer should be the same type as the GlobalVariable!");
Op<0>() = InitVal;
}
}
GlobalVariable::GlobalVariable(Module &M, Type *Ty, bool constant,
LinkageTypes Link, Constant *InitVal,
const Twine &Name, GlobalVariable *Before,
ThreadLocalMode TLMode, unsigned AddressSpace,
bool isExternallyInitialized)
: GlobalObject(PointerType::get(Ty, AddressSpace), Value::GlobalVariableVal,
OperandTraits<GlobalVariable>::op_begin(this),
InitVal != nullptr, Link, Name),
isConstantGlobal(constant),
isExternallyInitializedConstant(isExternallyInitialized) {
setThreadLocalMode(TLMode);
if (InitVal) {
assert(InitVal->getType() == Ty &&
"Initializer should be the same type as the GlobalVariable!");
Op<0>() = InitVal;
}
if (Before)
Before->getParent()->getGlobalList().insert(Before, this);
else
M.getGlobalList().push_back(this);
}
void GlobalVariable::setParent(Module *parent) {
Parent = parent;
}
void GlobalVariable::removeFromParent() {
getParent()->CallRemoveGlobalHook(this); // HLSL Change
getParent()->getGlobalList().remove(this);
}
void GlobalVariable::eraseFromParent() {
getParent()->CallRemoveGlobalHook(this); // HLSL Change
getParent()->getGlobalList().erase(this);
}
void GlobalVariable::setInitializer(Constant *InitVal) {
if (!InitVal) {
if (hasInitializer()) {
// Note, the num operands is used to compute the offset of the operand, so
// the order here matters. Clearing the operand then clearing the num
// operands ensures we have the correct offset to the operand.
Op<0>().set(nullptr);
setGlobalVariableNumOperands(0);
}
} else {
assert(InitVal->getType() == getType()->getElementType() &&
"Initializer type must match GlobalVariable type");
// Note, the num operands is used to compute the offset of the operand, so
// the order here matters. We need to set num operands to 1 first so that
// we get the correct offset to the first operand when we set it.
if (!hasInitializer())
setGlobalVariableNumOperands(1);
Op<0>().set(InitVal);
}
}
/// copyAttributesFrom - copy all additional attributes (those not needed to
/// create a GlobalVariable) from the GlobalVariable Src to this one.
void GlobalVariable::copyAttributesFrom(const GlobalValue *Src) {
assert(isa<GlobalVariable>(Src) && "Expected a GlobalVariable!");
GlobalObject::copyAttributesFrom(Src);
const GlobalVariable *SrcVar = cast<GlobalVariable>(Src);
setThreadLocalMode(SrcVar->getThreadLocalMode());
setExternallyInitialized(SrcVar->isExternallyInitialized());
}
//===----------------------------------------------------------------------===//
// GlobalAlias Implementation
//===----------------------------------------------------------------------===//
GlobalAlias::GlobalAlias(PointerType *Ty, LinkageTypes Link, const Twine &Name,
Constant *Aliasee, Module *ParentModule)
: GlobalValue(Ty, Value::GlobalAliasVal, &Op<0>(), 1, Link, Name) {
Op<0>() = Aliasee;
if (ParentModule)
ParentModule->getAliasList().push_back(this);
}
GlobalAlias *GlobalAlias::create(PointerType *Ty, LinkageTypes Link,
const Twine &Name, Constant *Aliasee,
Module *ParentModule) {
return new GlobalAlias(Ty, Link, Name, Aliasee, ParentModule);
}
GlobalAlias *GlobalAlias::create(PointerType *Ty, LinkageTypes Linkage,
const Twine &Name, Module *Parent) {
return create(Ty, Linkage, Name, nullptr, Parent);
}
GlobalAlias *GlobalAlias::create(PointerType *Ty, LinkageTypes Linkage,
const Twine &Name, GlobalValue *Aliasee) {
return create(Ty, Linkage, Name, Aliasee, Aliasee->getParent());
}
GlobalAlias *GlobalAlias::create(LinkageTypes Link, const Twine &Name,
GlobalValue *Aliasee) {
PointerType *PTy = Aliasee->getType();
return create(PTy, Link, Name, Aliasee);
}
GlobalAlias *GlobalAlias::create(const Twine &Name, GlobalValue *Aliasee) {
return create(Aliasee->getLinkage(), Name, Aliasee);
}
void GlobalAlias::setParent(Module *parent) {
Parent = parent;
}
void GlobalAlias::removeFromParent() {
getParent()->getAliasList().remove(this);
}
void GlobalAlias::eraseFromParent() {
getParent()->getAliasList().erase(this);
}
void GlobalAlias::setAliasee(Constant *Aliasee) {
assert((!Aliasee || Aliasee->getType() == getType()) &&
"Alias and aliasee types should match!");
setOperand(0, Aliasee);
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/ConstantFold.cpp | //===- ConstantFold.cpp - LLVM constant folder ----------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements folding of constants for LLVM. This implements the
// (internal) ConstantFold.h interface, which is used by the
// ConstantExpr::get* methods to automatically fold constants when possible.
//
// The current constant folding implementation is implemented in two pieces: the
// pieces that don't need DataLayout, and the pieces that do. This is to avoid
// a dependence in IR on Target.
//
//===----------------------------------------------------------------------===//
#include "ConstantFold.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Operator.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/MathExtras.h"
#include <limits>
using namespace llvm;
using namespace llvm::PatternMatch;
//===----------------------------------------------------------------------===//
// ConstantFold*Instruction Implementations
//===----------------------------------------------------------------------===//
/// BitCastConstantVector - Convert the specified vector Constant node to the
/// specified vector type. At this point, we know that the elements of the
/// input vector constant are all simple integer or FP values.
static Constant *BitCastConstantVector(Constant *CV, VectorType *DstTy) {
if (CV->isAllOnesValue()) return Constant::getAllOnesValue(DstTy);
if (CV->isNullValue()) return Constant::getNullValue(DstTy);
// If this cast changes element count then we can't handle it here:
// doing so requires endianness information. This should be handled by
// Analysis/ConstantFolding.cpp
unsigned NumElts = DstTy->getNumElements();
if (NumElts != CV->getType()->getVectorNumElements())
return nullptr;
Type *DstEltTy = DstTy->getElementType();
SmallVector<Constant*, 16> Result;
Type *Ty = IntegerType::get(CV->getContext(), 32);
for (unsigned i = 0; i != NumElts; ++i) {
Constant *C =
ConstantExpr::getExtractElement(CV, ConstantInt::get(Ty, i));
C = ConstantExpr::getBitCast(C, DstEltTy);
Result.push_back(C);
}
return ConstantVector::get(Result);
}
/// This function determines which opcode to use to fold two constant cast
/// expressions together. It uses CastInst::isEliminableCastPair to determine
/// the opcode. Consequently its just a wrapper around that function.
/// @brief Determine if it is valid to fold a cast of a cast
static unsigned
foldConstantCastPair(
unsigned opc, ///< opcode of the second cast constant expression
ConstantExpr *Op, ///< the first cast constant expression
Type *DstTy ///< destination type of the first cast
) {
assert(Op && Op->isCast() && "Can't fold cast of cast without a cast!");
assert(DstTy && DstTy->isFirstClassType() && "Invalid cast destination type");
assert(CastInst::isCast(opc) && "Invalid cast opcode");
// The the types and opcodes for the two Cast constant expressions
Type *SrcTy = Op->getOperand(0)->getType();
Type *MidTy = Op->getType();
Instruction::CastOps firstOp = Instruction::CastOps(Op->getOpcode());
Instruction::CastOps secondOp = Instruction::CastOps(opc);
// Assume that pointers are never more than 64 bits wide, and only use this
// for the middle type. Otherwise we could end up folding away illegal
// bitcasts between address spaces with different sizes.
IntegerType *FakeIntPtrTy = Type::getInt64Ty(DstTy->getContext());
// Let CastInst::isEliminableCastPair do the heavy lifting.
return CastInst::isEliminableCastPair(firstOp, secondOp, SrcTy, MidTy, DstTy,
nullptr, FakeIntPtrTy, nullptr);
}
static Constant *FoldBitCast(Constant *V, Type *DestTy) {
Type *SrcTy = V->getType();
if (SrcTy == DestTy)
return V; // no-op cast
// Check to see if we are casting a pointer to an aggregate to a pointer to
// the first element. If so, return the appropriate GEP instruction.
if (PointerType *PTy = dyn_cast<PointerType>(V->getType()))
if (PointerType *DPTy = dyn_cast<PointerType>(DestTy))
if (PTy->getAddressSpace() == DPTy->getAddressSpace()
&& DPTy->getElementType()->isSized()) {
SmallVector<Value*, 8> IdxList;
Value *Zero =
Constant::getNullValue(Type::getInt32Ty(DPTy->getContext()));
IdxList.push_back(Zero);
Type *ElTy = PTy->getElementType();
while (ElTy != DPTy->getElementType()) {
if (StructType *STy = dyn_cast<StructType>(ElTy)) {
if (STy->getNumElements() == 0) break;
ElTy = STy->getElementType(0);
IdxList.push_back(Zero);
} else if (SequentialType *STy =
dyn_cast<SequentialType>(ElTy)) {
if (ElTy->isPointerTy()) break; // Can't index into pointers!
ElTy = STy->getElementType();
IdxList.push_back(Zero);
} else {
break;
}
}
if (ElTy == DPTy->getElementType())
// This GEP is inbounds because all indices are zero.
return ConstantExpr::getInBoundsGetElementPtr(PTy->getElementType(),
V, IdxList);
}
// Handle casts from one vector constant to another. We know that the src
// and dest type have the same size (otherwise its an illegal cast).
if (VectorType *DestPTy = dyn_cast<VectorType>(DestTy)) {
if (VectorType *SrcTy = dyn_cast<VectorType>(V->getType())) {
assert(DestPTy->getBitWidth() == SrcTy->getBitWidth() &&
"Not cast between same sized vectors!");
SrcTy = nullptr;
// First, check for null. Undef is already handled.
if (isa<ConstantAggregateZero>(V))
return Constant::getNullValue(DestTy);
// Handle ConstantVector and ConstantAggregateVector.
return BitCastConstantVector(V, DestPTy);
}
// Canonicalize scalar-to-vector bitcasts into vector-to-vector bitcasts
// This allows for other simplifications (although some of them
// can only be handled by Analysis/ConstantFolding.cpp).
if (isa<ConstantInt>(V) || isa<ConstantFP>(V))
return ConstantExpr::getBitCast(ConstantVector::get(V), DestPTy);
}
// Finally, implement bitcast folding now. The code below doesn't handle
// bitcast right.
if (isa<ConstantPointerNull>(V)) // ptr->ptr cast.
return ConstantPointerNull::get(cast<PointerType>(DestTy));
// Handle integral constant input.
if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
if (DestTy->isIntegerTy())
// Integral -> Integral. This is a no-op because the bit widths must
// be the same. Consequently, we just fold to V.
return V;
// See note below regarding the PPC_FP128 restriction.
if (DestTy->isFloatingPointTy() && !DestTy->isPPC_FP128Ty())
return ConstantFP::get(DestTy->getContext(),
APFloat(DestTy->getFltSemantics(),
CI->getValue()));
// Otherwise, can't fold this (vector?)
return nullptr;
}
// Handle ConstantFP input: FP -> Integral.
if (ConstantFP *FP = dyn_cast<ConstantFP>(V)) {
// PPC_FP128 is really the sum of two consecutive doubles, where the first
// double is always stored first in memory, regardless of the target
// endianness. The memory layout of i128, however, depends on the target
// endianness, and so we can't fold this without target endianness
// information. This should instead be handled by
// Analysis/ConstantFolding.cpp
if (FP->getType()->isPPC_FP128Ty())
return nullptr;
return ConstantInt::get(FP->getContext(),
FP->getValueAPF().bitcastToAPInt());
}
return nullptr;
}
/// ExtractConstantBytes - V is an integer constant which only has a subset of
/// its bytes used. The bytes used are indicated by ByteStart (which is the
/// first byte used, counting from the least significant byte) and ByteSize,
/// which is the number of bytes used.
///
/// This function analyzes the specified constant to see if the specified byte
/// range can be returned as a simplified constant. If so, the constant is
/// returned, otherwise null is returned.
///
static Constant *ExtractConstantBytes(Constant *C, unsigned ByteStart,
unsigned ByteSize) {
assert(C->getType()->isIntegerTy() &&
(cast<IntegerType>(C->getType())->getBitWidth() & 7) == 0 &&
"Non-byte sized integer input");
unsigned CSize = cast<IntegerType>(C->getType())->getBitWidth()/8;
assert(ByteSize && "Must be accessing some piece");
assert(ByteStart+ByteSize <= CSize && "Extracting invalid piece from input");
assert(ByteSize != CSize && "Should not extract everything");
// Constant Integers are simple.
if (ConstantInt *CI = dyn_cast<ConstantInt>(C)) {
APInt V = CI->getValue();
if (ByteStart)
V = V.lshr(ByteStart*8);
V = V.trunc(ByteSize*8);
return ConstantInt::get(CI->getContext(), V);
}
// In the input is a constant expr, we might be able to recursively simplify.
// If not, we definitely can't do anything.
ConstantExpr *CE = dyn_cast<ConstantExpr>(C);
if (!CE) return nullptr;
switch (CE->getOpcode()) {
default: return nullptr;
case Instruction::Or: {
Constant *RHS = ExtractConstantBytes(CE->getOperand(1), ByteStart,ByteSize);
if (!RHS)
return nullptr;
// X | -1 -> -1.
if (ConstantInt *RHSC = dyn_cast<ConstantInt>(RHS))
if (RHSC->isAllOnesValue())
return RHSC;
Constant *LHS = ExtractConstantBytes(CE->getOperand(0), ByteStart,ByteSize);
if (!LHS)
return nullptr;
return ConstantExpr::getOr(LHS, RHS);
}
case Instruction::And: {
Constant *RHS = ExtractConstantBytes(CE->getOperand(1), ByteStart,ByteSize);
if (!RHS)
return nullptr;
// X & 0 -> 0.
if (RHS->isNullValue())
return RHS;
Constant *LHS = ExtractConstantBytes(CE->getOperand(0), ByteStart,ByteSize);
if (!LHS)
return nullptr;
return ConstantExpr::getAnd(LHS, RHS);
}
case Instruction::LShr: {
ConstantInt *Amt = dyn_cast<ConstantInt>(CE->getOperand(1));
if (!Amt)
return nullptr;
unsigned ShAmt = Amt->getZExtValue();
// Cannot analyze non-byte shifts.
if ((ShAmt & 7) != 0)
return nullptr;
ShAmt >>= 3;
// If the extract is known to be all zeros, return zero.
if (ByteStart >= CSize-ShAmt)
return Constant::getNullValue(IntegerType::get(CE->getContext(),
ByteSize*8));
// If the extract is known to be fully in the input, extract it.
if (ByteStart+ByteSize+ShAmt <= CSize)
return ExtractConstantBytes(CE->getOperand(0), ByteStart+ShAmt, ByteSize);
// TODO: Handle the 'partially zero' case.
return nullptr;
}
case Instruction::Shl: {
ConstantInt *Amt = dyn_cast<ConstantInt>(CE->getOperand(1));
if (!Amt)
return nullptr;
unsigned ShAmt = Amt->getZExtValue();
// Cannot analyze non-byte shifts.
if ((ShAmt & 7) != 0)
return nullptr;
ShAmt >>= 3;
// If the extract is known to be all zeros, return zero.
if (ByteStart+ByteSize <= ShAmt)
return Constant::getNullValue(IntegerType::get(CE->getContext(),
ByteSize*8));
// If the extract is known to be fully in the input, extract it.
if (ByteStart >= ShAmt)
return ExtractConstantBytes(CE->getOperand(0), ByteStart-ShAmt, ByteSize);
// TODO: Handle the 'partially zero' case.
return nullptr;
}
case Instruction::ZExt: {
unsigned SrcBitSize =
cast<IntegerType>(CE->getOperand(0)->getType())->getBitWidth();
// If extracting something that is completely zero, return 0.
if (ByteStart*8 >= SrcBitSize)
return Constant::getNullValue(IntegerType::get(CE->getContext(),
ByteSize*8));
// If exactly extracting the input, return it.
if (ByteStart == 0 && ByteSize*8 == SrcBitSize)
return CE->getOperand(0);
// If extracting something completely in the input, if if the input is a
// multiple of 8 bits, recurse.
if ((SrcBitSize&7) == 0 && (ByteStart+ByteSize)*8 <= SrcBitSize)
return ExtractConstantBytes(CE->getOperand(0), ByteStart, ByteSize);
// Otherwise, if extracting a subset of the input, which is not multiple of
// 8 bits, do a shift and trunc to get the bits.
if ((ByteStart+ByteSize)*8 < SrcBitSize) {
assert((SrcBitSize&7) && "Shouldn't get byte sized case here");
Constant *Res = CE->getOperand(0);
if (ByteStart)
Res = ConstantExpr::getLShr(Res,
ConstantInt::get(Res->getType(), ByteStart*8));
return ConstantExpr::getTrunc(Res, IntegerType::get(C->getContext(),
ByteSize*8));
}
// TODO: Handle the 'partially zero' case.
return nullptr;
}
}
}
/// getFoldedSizeOf - Return a ConstantExpr with type DestTy for sizeof
/// on Ty, with any known factors factored out. If Folded is false,
/// return null if no factoring was possible, to avoid endlessly
/// bouncing an unfoldable expression back into the top-level folder.
///
static Constant *getFoldedSizeOf(Type *Ty, Type *DestTy,
bool Folded) {
if (ArrayType *ATy = dyn_cast<ArrayType>(Ty)) {
Constant *N = ConstantInt::get(DestTy, ATy->getNumElements());
Constant *E = getFoldedSizeOf(ATy->getElementType(), DestTy, true);
return ConstantExpr::getNUWMul(E, N);
}
if (StructType *STy = dyn_cast<StructType>(Ty))
if (!STy->isPacked()) {
unsigned NumElems = STy->getNumElements();
// An empty struct has size zero.
if (NumElems == 0)
return ConstantExpr::getNullValue(DestTy);
// Check for a struct with all members having the same size.
Constant *MemberSize =
getFoldedSizeOf(STy->getElementType(0), DestTy, true);
bool AllSame = true;
for (unsigned i = 1; i != NumElems; ++i)
if (MemberSize !=
getFoldedSizeOf(STy->getElementType(i), DestTy, true)) {
AllSame = false;
break;
}
if (AllSame) {
Constant *N = ConstantInt::get(DestTy, NumElems);
return ConstantExpr::getNUWMul(MemberSize, N);
}
}
// Pointer size doesn't depend on the pointee type, so canonicalize them
// to an arbitrary pointee.
if (PointerType *PTy = dyn_cast<PointerType>(Ty))
if (!PTy->getElementType()->isIntegerTy(1))
return
getFoldedSizeOf(PointerType::get(IntegerType::get(PTy->getContext(), 1),
PTy->getAddressSpace()),
DestTy, true);
// If there's no interesting folding happening, bail so that we don't create
// a constant that looks like it needs folding but really doesn't.
if (!Folded)
return nullptr;
// Base case: Get a regular sizeof expression.
Constant *C = ConstantExpr::getSizeOf(Ty);
C = ConstantExpr::getCast(CastInst::getCastOpcode(C, false,
DestTy, false),
C, DestTy);
return C;
}
/// getFoldedAlignOf - Return a ConstantExpr with type DestTy for alignof
/// on Ty, with any known factors factored out. If Folded is false,
/// return null if no factoring was possible, to avoid endlessly
/// bouncing an unfoldable expression back into the top-level folder.
///
static Constant *getFoldedAlignOf(Type *Ty, Type *DestTy,
bool Folded) {
// The alignment of an array is equal to the alignment of the
// array element. Note that this is not always true for vectors.
if (ArrayType *ATy = dyn_cast<ArrayType>(Ty)) {
Constant *C = ConstantExpr::getAlignOf(ATy->getElementType());
C = ConstantExpr::getCast(CastInst::getCastOpcode(C, false,
DestTy,
false),
C, DestTy);
return C;
}
if (StructType *STy = dyn_cast<StructType>(Ty)) {
// Packed structs always have an alignment of 1.
if (STy->isPacked())
return ConstantInt::get(DestTy, 1);
// Otherwise, struct alignment is the maximum alignment of any member.
// Without target data, we can't compare much, but we can check to see
// if all the members have the same alignment.
unsigned NumElems = STy->getNumElements();
// An empty struct has minimal alignment.
if (NumElems == 0)
return ConstantInt::get(DestTy, 1);
// Check for a struct with all members having the same alignment.
Constant *MemberAlign =
getFoldedAlignOf(STy->getElementType(0), DestTy, true);
bool AllSame = true;
for (unsigned i = 1; i != NumElems; ++i)
if (MemberAlign != getFoldedAlignOf(STy->getElementType(i), DestTy, true)) {
AllSame = false;
break;
}
if (AllSame)
return MemberAlign;
}
// Pointer alignment doesn't depend on the pointee type, so canonicalize them
// to an arbitrary pointee.
if (PointerType *PTy = dyn_cast<PointerType>(Ty))
if (!PTy->getElementType()->isIntegerTy(1))
return
getFoldedAlignOf(PointerType::get(IntegerType::get(PTy->getContext(),
1),
PTy->getAddressSpace()),
DestTy, true);
// If there's no interesting folding happening, bail so that we don't create
// a constant that looks like it needs folding but really doesn't.
if (!Folded)
return nullptr;
// Base case: Get a regular alignof expression.
Constant *C = ConstantExpr::getAlignOf(Ty);
C = ConstantExpr::getCast(CastInst::getCastOpcode(C, false,
DestTy, false),
C, DestTy);
return C;
}
/// getFoldedOffsetOf - Return a ConstantExpr with type DestTy for offsetof
/// on Ty and FieldNo, with any known factors factored out. If Folded is false,
/// return null if no factoring was possible, to avoid endlessly
/// bouncing an unfoldable expression back into the top-level folder.
///
static Constant *getFoldedOffsetOf(Type *Ty, Constant *FieldNo,
Type *DestTy,
bool Folded) {
if (ArrayType *ATy = dyn_cast<ArrayType>(Ty)) {
Constant *N = ConstantExpr::getCast(CastInst::getCastOpcode(FieldNo, false,
DestTy, false),
FieldNo, DestTy);
Constant *E = getFoldedSizeOf(ATy->getElementType(), DestTy, true);
return ConstantExpr::getNUWMul(E, N);
}
if (StructType *STy = dyn_cast<StructType>(Ty))
if (!STy->isPacked()) {
unsigned NumElems = STy->getNumElements();
// An empty struct has no members.
if (NumElems == 0)
return nullptr;
// Check for a struct with all members having the same size.
Constant *MemberSize =
getFoldedSizeOf(STy->getElementType(0), DestTy, true);
bool AllSame = true;
for (unsigned i = 1; i != NumElems; ++i)
if (MemberSize !=
getFoldedSizeOf(STy->getElementType(i), DestTy, true)) {
AllSame = false;
break;
}
if (AllSame) {
Constant *N = ConstantExpr::getCast(CastInst::getCastOpcode(FieldNo,
false,
DestTy,
false),
FieldNo, DestTy);
return ConstantExpr::getNUWMul(MemberSize, N);
}
}
// If there's no interesting folding happening, bail so that we don't create
// a constant that looks like it needs folding but really doesn't.
if (!Folded)
return nullptr;
// Base case: Get a regular offsetof expression.
Constant *C = ConstantExpr::getOffsetOf(Ty, FieldNo);
C = ConstantExpr::getCast(CastInst::getCastOpcode(C, false,
DestTy, false),
C, DestTy);
return C;
}
Constant *llvm::ConstantFoldCastInstruction(unsigned opc, Constant *V,
Type *DestTy) {
if (isa<UndefValue>(V)) {
// zext(undef) = 0, because the top bits will be zero.
// sext(undef) = 0, because the top bits will all be the same.
// [us]itofp(undef) = 0, because the result value is bounded.
if (opc == Instruction::ZExt || opc == Instruction::SExt ||
opc == Instruction::UIToFP || opc == Instruction::SIToFP)
return Constant::getNullValue(DestTy);
return UndefValue::get(DestTy);
}
if (V->isNullValue() && !DestTy->isX86_MMXTy())
return Constant::getNullValue(DestTy);
// If the cast operand is a constant expression, there's a few things we can
// do to try to simplify it.
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
if (CE->isCast()) {
// Try hard to fold cast of cast because they are often eliminable.
if (unsigned newOpc = foldConstantCastPair(opc, CE, DestTy))
return ConstantExpr::getCast(newOpc, CE->getOperand(0), DestTy);
} else if (CE->getOpcode() == Instruction::GetElementPtr &&
false && // HLSL change - not fold gep 0, ... 0 for HLSL.
// Do not fold addrspacecast (gep 0, .., 0). It might make the
// addrspacecast uncanonicalized.
opc != Instruction::AddrSpaceCast) {
// If all of the indexes in the GEP are null values, there is no pointer
// adjustment going on. We might as well cast the source pointer.
bool isAllNull = true;
for (unsigned i = 1, e = CE->getNumOperands(); i != e; ++i)
if (!CE->getOperand(i)->isNullValue()) {
isAllNull = false;
break;
}
if (isAllNull)
// This is casting one pointer type to another, always BitCast
return ConstantExpr::getPointerCast(CE->getOperand(0), DestTy);
}
}
// If the cast operand is a constant vector, perform the cast by
// operating on each element. In the cast of bitcasts, the element
// count may be mismatched; don't attempt to handle that here.
if ((isa<ConstantVector>(V) || isa<ConstantDataVector>(V)) &&
DestTy->isVectorTy() &&
DestTy->getVectorNumElements() == V->getType()->getVectorNumElements()) {
SmallVector<Constant*, 16> res;
VectorType *DestVecTy = cast<VectorType>(DestTy);
Type *DstEltTy = DestVecTy->getElementType();
Type *Ty = IntegerType::get(V->getContext(), 32);
for (unsigned i = 0, e = V->getType()->getVectorNumElements(); i != e; ++i) {
Constant *C =
ConstantExpr::getExtractElement(V, ConstantInt::get(Ty, i));
res.push_back(ConstantExpr::getCast(opc, C, DstEltTy));
}
return ConstantVector::get(res);
}
// We actually have to do a cast now. Perform the cast according to the
// opcode specified.
switch (opc) {
default:
llvm_unreachable("Failed to cast constant expression");
case Instruction::FPTrunc:
case Instruction::FPExt:
if (ConstantFP *FPC = dyn_cast<ConstantFP>(V)) {
bool ignored;
APFloat Val = FPC->getValueAPF();
Val.convert(DestTy->isHalfTy() ? APFloat::IEEEhalf :
DestTy->isFloatTy() ? APFloat::IEEEsingle :
DestTy->isDoubleTy() ? APFloat::IEEEdouble :
DestTy->isX86_FP80Ty() ? APFloat::x87DoubleExtended :
DestTy->isFP128Ty() ? APFloat::IEEEquad :
DestTy->isPPC_FP128Ty() ? APFloat::PPCDoubleDouble :
APFloat::Bogus,
APFloat::rmNearestTiesToEven, &ignored);
return ConstantFP::get(V->getContext(), Val);
}
return nullptr; // Can't fold.
case Instruction::FPToUI:
case Instruction::FPToSI:
if (ConstantFP *FPC = dyn_cast<ConstantFP>(V)) {
const APFloat &V = FPC->getValueAPF();
bool ignored;
uint64_t x[2];
uint32_t DestBitWidth = cast<IntegerType>(DestTy)->getBitWidth();
if (APFloat::opInvalidOp ==
V.convertToInteger(x, DestBitWidth, opc==Instruction::FPToSI,
APFloat::rmTowardZero, &ignored)) {
// Undefined behavior invoked - the destination type can't represent
// the input constant.
return UndefValue::get(DestTy);
}
APInt Val(DestBitWidth, x);
return ConstantInt::get(FPC->getContext(), Val);
}
return nullptr; // Can't fold.
case Instruction::IntToPtr: //always treated as unsigned
if (V->isNullValue()) // Is it an integral null value?
return ConstantPointerNull::get(cast<PointerType>(DestTy));
return nullptr; // Other pointer types cannot be casted
case Instruction::PtrToInt: // always treated as unsigned
// Is it a null pointer value?
if (V->isNullValue())
return ConstantInt::get(DestTy, 0);
// If this is a sizeof-like expression, pull out multiplications by
// known factors to expose them to subsequent folding. If it's an
// alignof-like expression, factor out known factors.
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
if (CE->getOpcode() == Instruction::GetElementPtr &&
CE->getOperand(0)->isNullValue()) {
GEPOperator *GEPO = cast<GEPOperator>(CE);
Type *Ty = GEPO->getSourceElementType();
if (CE->getNumOperands() == 2) {
// Handle a sizeof-like expression.
Constant *Idx = CE->getOperand(1);
bool isOne = isa<ConstantInt>(Idx) && cast<ConstantInt>(Idx)->isOne();
if (Constant *C = getFoldedSizeOf(Ty, DestTy, !isOne)) {
Idx = ConstantExpr::getCast(CastInst::getCastOpcode(Idx, true,
DestTy, false),
Idx, DestTy);
return ConstantExpr::getMul(C, Idx);
}
} else if (CE->getNumOperands() == 3 &&
CE->getOperand(1)->isNullValue()) {
// Handle an alignof-like expression.
if (StructType *STy = dyn_cast<StructType>(Ty))
if (!STy->isPacked()) {
ConstantInt *CI = cast<ConstantInt>(CE->getOperand(2));
if (CI->isOne() &&
STy->getNumElements() == 2 &&
STy->getElementType(0)->isIntegerTy(1)) {
return getFoldedAlignOf(STy->getElementType(1), DestTy, false);
}
}
// Handle an offsetof-like expression.
if (Ty->isStructTy() || Ty->isArrayTy()) {
if (Constant *C = getFoldedOffsetOf(Ty, CE->getOperand(2),
DestTy, false))
return C;
}
}
}
// Other pointer types cannot be casted
return nullptr;
case Instruction::UIToFP:
case Instruction::SIToFP:
if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
APInt api = CI->getValue();
APFloat apf(DestTy->getFltSemantics(),
APInt::getNullValue(DestTy->getPrimitiveSizeInBits()));
if (APFloat::opOverflow &
apf.convertFromAPInt(api, opc==Instruction::SIToFP,
APFloat::rmNearestTiesToEven)) {
// Undefined behavior invoked - the destination type can't represent
// the input constant.
return UndefValue::get(DestTy);
}
return ConstantFP::get(V->getContext(), apf);
}
return nullptr;
case Instruction::ZExt:
if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
uint32_t BitWidth = cast<IntegerType>(DestTy)->getBitWidth();
return ConstantInt::get(V->getContext(),
CI->getValue().zext(BitWidth));
}
return nullptr;
case Instruction::SExt:
if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
uint32_t BitWidth = cast<IntegerType>(DestTy)->getBitWidth();
return ConstantInt::get(V->getContext(),
CI->getValue().sext(BitWidth));
}
return nullptr;
case Instruction::Trunc: {
if (V->getType()->isVectorTy())
return nullptr;
uint32_t DestBitWidth = cast<IntegerType>(DestTy)->getBitWidth();
if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
return ConstantInt::get(V->getContext(),
CI->getValue().trunc(DestBitWidth));
}
// The input must be a constantexpr. See if we can simplify this based on
// the bytes we are demanding. Only do this if the source and dest are an
// even multiple of a byte.
if ((DestBitWidth & 7) == 0 &&
(cast<IntegerType>(V->getType())->getBitWidth() & 7) == 0)
if (Constant *Res = ExtractConstantBytes(V, 0, DestBitWidth / 8))
return Res;
return nullptr;
}
case Instruction::BitCast:
return FoldBitCast(V, DestTy);
case Instruction::AddrSpaceCast:
return nullptr;
}
}
Constant *llvm::ConstantFoldSelectInstruction(Constant *Cond,
Constant *V1, Constant *V2) {
// Check for i1 and vector true/false conditions.
if (Cond->isNullValue()) return V2;
if (Cond->isAllOnesValue()) return V1;
// If the condition is a vector constant, fold the result elementwise.
if (ConstantVector *CondV = dyn_cast<ConstantVector>(Cond)) {
SmallVector<Constant*, 16> Result;
Type *Ty = IntegerType::get(CondV->getContext(), 32);
for (unsigned i = 0, e = V1->getType()->getVectorNumElements(); i != e;++i){
Constant *V;
Constant *V1Element = ConstantExpr::getExtractElement(V1,
ConstantInt::get(Ty, i));
Constant *V2Element = ConstantExpr::getExtractElement(V2,
ConstantInt::get(Ty, i));
Constant *Cond = dyn_cast<Constant>(CondV->getOperand(i));
if (V1Element == V2Element) {
V = V1Element;
} else if (isa<UndefValue>(Cond)) {
V = isa<UndefValue>(V1Element) ? V1Element : V2Element;
} else {
if (!isa<ConstantInt>(Cond)) break;
V = Cond->isNullValue() ? V2Element : V1Element;
}
Result.push_back(V);
}
// If we were able to build the vector, return it.
if (Result.size() == V1->getType()->getVectorNumElements())
return ConstantVector::get(Result);
}
if (isa<UndefValue>(Cond)) {
if (isa<UndefValue>(V1)) return V1;
return V2;
}
if (isa<UndefValue>(V1)) return V2;
if (isa<UndefValue>(V2)) return V1;
if (V1 == V2) return V1;
if (ConstantExpr *TrueVal = dyn_cast<ConstantExpr>(V1)) {
if (TrueVal->getOpcode() == Instruction::Select)
if (TrueVal->getOperand(0) == Cond)
return ConstantExpr::getSelect(Cond, TrueVal->getOperand(1), V2);
}
if (ConstantExpr *FalseVal = dyn_cast<ConstantExpr>(V2)) {
if (FalseVal->getOpcode() == Instruction::Select)
if (FalseVal->getOperand(0) == Cond)
return ConstantExpr::getSelect(Cond, V1, FalseVal->getOperand(2));
}
return nullptr;
}
Constant *llvm::ConstantFoldExtractElementInstruction(Constant *Val,
Constant *Idx) {
if (isa<UndefValue>(Val)) // ee(undef, x) -> undef
return UndefValue::get(Val->getType()->getVectorElementType());
if (Val->isNullValue()) // ee(zero, x) -> zero
return Constant::getNullValue(Val->getType()->getVectorElementType());
// ee({w,x,y,z}, undef) -> undef
if (isa<UndefValue>(Idx))
return UndefValue::get(Val->getType()->getVectorElementType());
if (ConstantInt *CIdx = dyn_cast<ConstantInt>(Idx)) {
// ee({w,x,y,z}, wrong_value) -> undef
if (CIdx->uge(Val->getType()->getVectorNumElements()))
return UndefValue::get(Val->getType()->getVectorElementType());
return Val->getAggregateElement(CIdx->getZExtValue());
}
return nullptr;
}
Constant *llvm::ConstantFoldInsertElementInstruction(Constant *Val,
Constant *Elt,
Constant *Idx) {
if (isa<UndefValue>(Idx))
return UndefValue::get(Val->getType());
ConstantInt *CIdx = dyn_cast<ConstantInt>(Idx);
if (!CIdx) return nullptr;
unsigned NumElts = Val->getType()->getVectorNumElements();
if (CIdx->uge(NumElts))
return UndefValue::get(Val->getType());
SmallVector<Constant*, 16> Result;
Result.reserve(NumElts);
auto *Ty = Type::getInt32Ty(Val->getContext());
uint64_t IdxVal = CIdx->getZExtValue();
for (unsigned i = 0; i != NumElts; ++i) {
if (i == IdxVal) {
Result.push_back(Elt);
continue;
}
Constant *C = ConstantExpr::getExtractElement(Val, ConstantInt::get(Ty, i));
Result.push_back(C);
}
return ConstantVector::get(Result);
}
Constant *llvm::ConstantFoldShuffleVectorInstruction(Constant *V1,
Constant *V2,
Constant *Mask) {
unsigned MaskNumElts = Mask->getType()->getVectorNumElements();
Type *EltTy = V1->getType()->getVectorElementType();
// Undefined shuffle mask -> undefined value.
if (isa<UndefValue>(Mask))
return UndefValue::get(VectorType::get(EltTy, MaskNumElts));
// Don't break the bitcode reader hack.
if (isa<ConstantExpr>(Mask)) return nullptr;
unsigned SrcNumElts = V1->getType()->getVectorNumElements();
// Loop over the shuffle mask, evaluating each element.
SmallVector<Constant*, 32> Result;
for (unsigned i = 0; i != MaskNumElts; ++i) {
int Elt = ShuffleVectorInst::getMaskValue(Mask, i);
if (Elt == -1) {
Result.push_back(UndefValue::get(EltTy));
continue;
}
Constant *InElt;
if (unsigned(Elt) >= SrcNumElts*2)
InElt = UndefValue::get(EltTy);
else if (unsigned(Elt) >= SrcNumElts) {
Type *Ty = IntegerType::get(V2->getContext(), 32);
InElt =
ConstantExpr::getExtractElement(V2,
ConstantInt::get(Ty, Elt - SrcNumElts));
} else {
Type *Ty = IntegerType::get(V1->getContext(), 32);
InElt = ConstantExpr::getExtractElement(V1, ConstantInt::get(Ty, Elt));
}
Result.push_back(InElt);
}
return ConstantVector::get(Result);
}
Constant *llvm::ConstantFoldExtractValueInstruction(Constant *Agg,
ArrayRef<unsigned> Idxs) {
// Base case: no indices, so return the entire value.
if (Idxs.empty())
return Agg;
if (Constant *C = Agg->getAggregateElement(Idxs[0]))
return ConstantFoldExtractValueInstruction(C, Idxs.slice(1));
return nullptr;
}
Constant *llvm::ConstantFoldInsertValueInstruction(Constant *Agg,
Constant *Val,
ArrayRef<unsigned> Idxs) {
// Base case: no indices, so replace the entire value.
if (Idxs.empty())
return Val;
unsigned NumElts;
if (StructType *ST = dyn_cast<StructType>(Agg->getType()))
NumElts = ST->getNumElements();
else if (ArrayType *AT = dyn_cast<ArrayType>(Agg->getType()))
NumElts = AT->getNumElements();
else
NumElts = Agg->getType()->getVectorNumElements();
SmallVector<Constant*, 32> Result;
for (unsigned i = 0; i != NumElts; ++i) {
Constant *C = Agg->getAggregateElement(i);
if (!C) return nullptr;
if (Idxs[0] == i)
C = ConstantFoldInsertValueInstruction(C, Val, Idxs.slice(1));
Result.push_back(C);
}
if (StructType *ST = dyn_cast<StructType>(Agg->getType()))
return ConstantStruct::get(ST, Result);
if (ArrayType *AT = dyn_cast<ArrayType>(Agg->getType()))
return ConstantArray::get(AT, Result);
return ConstantVector::get(Result);
}
Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode,
Constant *C1, Constant *C2) {
// Handle UndefValue up front.
if (isa<UndefValue>(C1) || isa<UndefValue>(C2)) {
switch (Opcode) {
case Instruction::Xor:
if (isa<UndefValue>(C1) && isa<UndefValue>(C2))
// Handle undef ^ undef -> 0 special case. This is a common
// idiom (misuse).
return Constant::getNullValue(C1->getType());
LLVM_FALLTHROUGH; // HLSL Change
case Instruction::Add:
case Instruction::Sub:
return UndefValue::get(C1->getType());
case Instruction::And:
if (isa<UndefValue>(C1) && isa<UndefValue>(C2)) // undef & undef -> undef
return C1;
return Constant::getNullValue(C1->getType()); // undef & X -> 0
case Instruction::Mul: {
// undef * undef -> undef
if (isa<UndefValue>(C1) && isa<UndefValue>(C2))
return C1;
const APInt *CV;
// X * undef -> undef if X is odd
if (match(C1, m_APInt(CV)) || match(C2, m_APInt(CV)))
if ((*CV)[0])
return UndefValue::get(C1->getType());
// X * undef -> 0 otherwise
return Constant::getNullValue(C1->getType());
}
case Instruction::SDiv:
case Instruction::UDiv:
// X / undef -> undef
if (match(C1, m_Zero()))
return C2;
// undef / 0 -> undef
// undef / 1 -> undef
if (match(C2, m_Zero()) || match(C2, m_One()))
return C1;
// undef / X -> 0 otherwise
return Constant::getNullValue(C1->getType());
case Instruction::URem:
case Instruction::SRem:
// X % undef -> undef
if (match(C2, m_Undef()))
return C2;
// undef % 0 -> undef
if (match(C2, m_Zero()))
return C1;
// undef % X -> 0 otherwise
return Constant::getNullValue(C1->getType());
case Instruction::Or: // X | undef -> -1
if (isa<UndefValue>(C1) && isa<UndefValue>(C2)) // undef | undef -> undef
return C1;
return Constant::getAllOnesValue(C1->getType()); // undef | X -> ~0
case Instruction::LShr:
// X >>l undef -> undef
if (isa<UndefValue>(C2))
return C2;
// undef >>l 0 -> undef
if (match(C2, m_Zero()))
return C1;
// undef >>l X -> 0
return Constant::getNullValue(C1->getType());
case Instruction::AShr:
// X >>a undef -> undef
if (isa<UndefValue>(C2))
return C2;
// undef >>a 0 -> undef
if (match(C2, m_Zero()))
return C1;
// TODO: undef >>a X -> undef if the shift is exact
// undef >>a X -> 0
return Constant::getNullValue(C1->getType());
case Instruction::Shl:
// X << undef -> undef
if (isa<UndefValue>(C2))
return C2;
// undef << 0 -> undef
if (match(C2, m_Zero()))
return C1;
// undef << X -> 0
return Constant::getNullValue(C1->getType());
}
}
// Handle simplifications when the RHS is a constant int.
if (ConstantInt *CI2 = dyn_cast<ConstantInt>(C2)) {
switch (Opcode) {
case Instruction::Add:
if (CI2->equalsInt(0)) return C1; // X + 0 == X
break;
case Instruction::Sub:
if (CI2->equalsInt(0)) return C1; // X - 0 == X
break;
case Instruction::Mul:
if (CI2->equalsInt(0)) return C2; // X * 0 == 0
if (CI2->equalsInt(1))
return C1; // X * 1 == X
break;
case Instruction::UDiv:
case Instruction::SDiv:
if (CI2->equalsInt(1))
return C1; // X / 1 == X
if (CI2->equalsInt(0))
return UndefValue::get(CI2->getType()); // X / 0 == undef
break;
case Instruction::URem:
case Instruction::SRem:
if (CI2->equalsInt(1))
return Constant::getNullValue(CI2->getType()); // X % 1 == 0
if (CI2->equalsInt(0))
return UndefValue::get(CI2->getType()); // X % 0 == undef
break;
case Instruction::And:
if (CI2->isZero()) return C2; // X & 0 == 0
if (CI2->isAllOnesValue())
return C1; // X & -1 == X
if (ConstantExpr *CE1 = dyn_cast<ConstantExpr>(C1)) {
// (zext i32 to i64) & 4294967295 -> (zext i32 to i64)
if (CE1->getOpcode() == Instruction::ZExt) {
unsigned DstWidth = CI2->getType()->getBitWidth();
unsigned SrcWidth =
CE1->getOperand(0)->getType()->getPrimitiveSizeInBits();
APInt PossiblySetBits(APInt::getLowBitsSet(DstWidth, SrcWidth));
if ((PossiblySetBits & CI2->getValue()) == PossiblySetBits)
return C1;
}
// If and'ing the address of a global with a constant, fold it.
if (CE1->getOpcode() == Instruction::PtrToInt &&
isa<GlobalValue>(CE1->getOperand(0))) {
GlobalValue *GV = cast<GlobalValue>(CE1->getOperand(0));
// Functions are at least 4-byte aligned.
unsigned GVAlign = GV->getAlignment();
if (isa<Function>(GV))
GVAlign = std::max(GVAlign, 4U);
if (GVAlign > 1) {
unsigned DstWidth = CI2->getType()->getBitWidth();
unsigned SrcWidth = std::min(DstWidth, Log2_32(GVAlign));
APInt BitsNotSet(APInt::getLowBitsSet(DstWidth, SrcWidth));
// If checking bits we know are clear, return zero.
if ((CI2->getValue() & BitsNotSet) == CI2->getValue())
return Constant::getNullValue(CI2->getType());
}
}
}
break;
case Instruction::Or:
if (CI2->equalsInt(0)) return C1; // X | 0 == X
if (CI2->isAllOnesValue())
return C2; // X | -1 == -1
break;
case Instruction::Xor:
if (CI2->equalsInt(0)) return C1; // X ^ 0 == X
if (ConstantExpr *CE1 = dyn_cast<ConstantExpr>(C1)) {
switch (CE1->getOpcode()) {
default: break;
case Instruction::ICmp:
case Instruction::FCmp:
// cmp pred ^ true -> cmp !pred
assert(CI2->equalsInt(1));
CmpInst::Predicate pred = (CmpInst::Predicate)CE1->getPredicate();
pred = CmpInst::getInversePredicate(pred);
return ConstantExpr::getCompare(pred, CE1->getOperand(0),
CE1->getOperand(1));
}
}
break;
case Instruction::AShr:
// ashr (zext C to Ty), C2 -> lshr (zext C, CSA), C2
if (ConstantExpr *CE1 = dyn_cast<ConstantExpr>(C1))
if (CE1->getOpcode() == Instruction::ZExt) // Top bits known zero.
return ConstantExpr::getLShr(C1, C2);
break;
}
} else if (isa<ConstantInt>(C1)) {
// If C1 is a ConstantInt and C2 is not, swap the operands.
if (Instruction::isCommutative(Opcode))
return ConstantExpr::get(Opcode, C2, C1);
}
// At this point we know neither constant is an UndefValue.
if (ConstantInt *CI1 = dyn_cast<ConstantInt>(C1)) {
if (ConstantInt *CI2 = dyn_cast<ConstantInt>(C2)) {
const APInt &C1V = CI1->getValue();
const APInt &C2V = CI2->getValue();
switch (Opcode) {
default:
break;
case Instruction::Add:
return ConstantInt::get(CI1->getContext(), C1V + C2V);
case Instruction::Sub:
return ConstantInt::get(CI1->getContext(), C1V - C2V);
case Instruction::Mul:
return ConstantInt::get(CI1->getContext(), C1V * C2V);
case Instruction::UDiv:
assert(!CI2->isNullValue() && "Div by zero handled above");
return ConstantInt::get(CI1->getContext(), C1V.udiv(C2V));
case Instruction::SDiv:
assert(!CI2->isNullValue() && "Div by zero handled above");
if (C2V.isAllOnesValue() && C1V.isMinSignedValue())
return UndefValue::get(CI1->getType()); // MIN_INT / -1 -> undef
return ConstantInt::get(CI1->getContext(), C1V.sdiv(C2V));
case Instruction::URem:
assert(!CI2->isNullValue() && "Div by zero handled above");
return ConstantInt::get(CI1->getContext(), C1V.urem(C2V));
case Instruction::SRem:
assert(!CI2->isNullValue() && "Div by zero handled above");
if (C2V.isAllOnesValue() && C1V.isMinSignedValue())
return UndefValue::get(CI1->getType()); // MIN_INT % -1 -> undef
return ConstantInt::get(CI1->getContext(), C1V.srem(C2V));
case Instruction::And:
return ConstantInt::get(CI1->getContext(), C1V & C2V);
case Instruction::Or:
return ConstantInt::get(CI1->getContext(), C1V | C2V);
case Instruction::Xor:
return ConstantInt::get(CI1->getContext(), C1V ^ C2V);
case Instruction::Shl:
if (C2V.ult(C1V.getBitWidth()))
return ConstantInt::get(CI1->getContext(), C1V.shl(C2V));
return UndefValue::get(C1->getType()); // too big shift is undef
case Instruction::LShr:
if (C2V.ult(C1V.getBitWidth()))
return ConstantInt::get(CI1->getContext(), C1V.lshr(C2V));
return UndefValue::get(C1->getType()); // too big shift is undef
case Instruction::AShr:
if (C2V.ult(C1V.getBitWidth()))
return ConstantInt::get(CI1->getContext(), C1V.ashr(C2V));
return UndefValue::get(C1->getType()); // too big shift is undef
}
}
switch (Opcode) {
case Instruction::SDiv:
case Instruction::UDiv:
case Instruction::URem:
case Instruction::SRem:
case Instruction::LShr:
case Instruction::AShr:
case Instruction::Shl:
if (CI1->equalsInt(0)) return C1;
break;
default:
break;
}
} else if (ConstantFP *CFP1 = dyn_cast<ConstantFP>(C1)) {
if (ConstantFP *CFP2 = dyn_cast<ConstantFP>(C2)) {
APFloat C1V = CFP1->getValueAPF();
APFloat C2V = CFP2->getValueAPF();
APFloat C3V = C1V; // copy for modification
switch (Opcode) {
default:
break;
case Instruction::FAdd:
(void)C3V.add(C2V, APFloat::rmNearestTiesToEven);
return ConstantFP::get(C1->getContext(), C3V);
case Instruction::FSub:
(void)C3V.subtract(C2V, APFloat::rmNearestTiesToEven);
return ConstantFP::get(C1->getContext(), C3V);
case Instruction::FMul:
(void)C3V.multiply(C2V, APFloat::rmNearestTiesToEven);
return ConstantFP::get(C1->getContext(), C3V);
case Instruction::FDiv:
(void)C3V.divide(C2V, APFloat::rmNearestTiesToEven);
return ConstantFP::get(C1->getContext(), C3V);
case Instruction::FRem:
(void)C3V.mod(C2V, APFloat::rmNearestTiesToEven);
return ConstantFP::get(C1->getContext(), C3V);
}
}
} else if (VectorType *VTy = dyn_cast<VectorType>(C1->getType())) {
// Perform elementwise folding.
SmallVector<Constant*, 16> Result;
Type *Ty = IntegerType::get(VTy->getContext(), 32);
for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) {
Constant *LHS =
ConstantExpr::getExtractElement(C1, ConstantInt::get(Ty, i));
Constant *RHS =
ConstantExpr::getExtractElement(C2, ConstantInt::get(Ty, i));
Result.push_back(ConstantExpr::get(Opcode, LHS, RHS));
}
return ConstantVector::get(Result);
}
if (ConstantExpr *CE1 = dyn_cast<ConstantExpr>(C1)) {
// There are many possible foldings we could do here. We should probably
// at least fold add of a pointer with an integer into the appropriate
// getelementptr. This will improve alias analysis a bit.
// Given ((a + b) + c), if (b + c) folds to something interesting, return
// (a + (b + c)).
if (Instruction::isAssociative(Opcode) && CE1->getOpcode() == Opcode) {
Constant *T = ConstantExpr::get(Opcode, CE1->getOperand(1), C2);
if (!isa<ConstantExpr>(T) || cast<ConstantExpr>(T)->getOpcode() != Opcode)
return ConstantExpr::get(Opcode, CE1->getOperand(0), T);
}
} else if (isa<ConstantExpr>(C2)) {
// If C2 is a constant expr and C1 isn't, flop them around and fold the
// other way if possible.
if (Instruction::isCommutative(Opcode))
return ConstantFoldBinaryInstruction(Opcode, C2, C1);
}
// i1 can be simplified in many cases.
if (C1->getType()->isIntegerTy(1)) {
switch (Opcode) {
case Instruction::Add:
case Instruction::Sub:
return ConstantExpr::getXor(C1, C2);
case Instruction::Mul:
return ConstantExpr::getAnd(C1, C2);
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
// We can assume that C2 == 0. If it were one the result would be
// undefined because the shift value is as large as the bitwidth.
return C1;
case Instruction::SDiv:
case Instruction::UDiv:
// We can assume that C2 == 1. If it were zero the result would be
// undefined through division by zero.
return C1;
case Instruction::URem:
case Instruction::SRem:
// We can assume that C2 == 1. If it were zero the result would be
// undefined through division by zero.
return ConstantInt::getFalse(C1->getContext());
default:
break;
}
}
// We don't know how to fold this.
return nullptr;
}
/// isZeroSizedType - This type is zero sized if its an array or structure of
/// zero sized types. The only leaf zero sized type is an empty structure.
static bool isMaybeZeroSizedType(Type *Ty) {
if (StructType *STy = dyn_cast<StructType>(Ty)) {
if (STy->isOpaque()) return true; // Can't say.
// If all of elements have zero size, this does too.
for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i)
if (!isMaybeZeroSizedType(STy->getElementType(i))) return false;
return true;
} else if (ArrayType *ATy = dyn_cast<ArrayType>(Ty)) {
return isMaybeZeroSizedType(ATy->getElementType());
}
return false;
}
/// IdxCompare - Compare the two constants as though they were getelementptr
/// indices. This allows coersion of the types to be the same thing.
///
/// If the two constants are the "same" (after coersion), return 0. If the
/// first is less than the second, return -1, if the second is less than the
/// first, return 1. If the constants are not integral, return -2.
///
static int IdxCompare(Constant *C1, Constant *C2, Type *ElTy) {
if (C1 == C2) return 0;
// Ok, we found a different index. If they are not ConstantInt, we can't do
// anything with them.
if (!isa<ConstantInt>(C1) || !isa<ConstantInt>(C2))
return -2; // don't know!
// We cannot compare the indices if they don't fit in an int64_t.
if (cast<ConstantInt>(C1)->getValue().getActiveBits() > 64 ||
cast<ConstantInt>(C2)->getValue().getActiveBits() > 64)
return -2; // don't know!
// Ok, we have two differing integer indices. Sign extend them to be the same
// type.
int64_t C1Val = cast<ConstantInt>(C1)->getSExtValue();
int64_t C2Val = cast<ConstantInt>(C2)->getSExtValue();
if (C1Val == C2Val) return 0; // They are equal
// If the type being indexed over is really just a zero sized type, there is
// no pointer difference being made here.
if (isMaybeZeroSizedType(ElTy))
return -2; // dunno.
// If they are really different, now that they are the same type, then we
// found a difference!
if (C1Val < C2Val)
return -1;
else
return 1;
}
/// evaluateFCmpRelation - This function determines if there is anything we can
/// decide about the two constants provided. This doesn't need to handle simple
/// things like ConstantFP comparisons, but should instead handle ConstantExprs.
/// If we can determine that the two constants have a particular relation to
/// each other, we should return the corresponding FCmpInst predicate,
/// otherwise return FCmpInst::BAD_FCMP_PREDICATE. This is used below in
/// ConstantFoldCompareInstruction.
///
/// To simplify this code we canonicalize the relation so that the first
/// operand is always the most "complex" of the two. We consider ConstantFP
/// to be the simplest, and ConstantExprs to be the most complex.
static FCmpInst::Predicate evaluateFCmpRelation(Constant *V1, Constant *V2) {
assert(V1->getType() == V2->getType() &&
"Cannot compare values of different types!");
// Handle degenerate case quickly
if (V1 == V2) return FCmpInst::FCMP_OEQ;
if (!isa<ConstantExpr>(V1)) {
if (!isa<ConstantExpr>(V2)) {
// Simple case, use the standard constant folder.
ConstantInt *R = nullptr;
R = dyn_cast<ConstantInt>(
ConstantExpr::getFCmp(FCmpInst::FCMP_OEQ, V1, V2));
if (R && !R->isZero())
return FCmpInst::FCMP_OEQ;
R = dyn_cast<ConstantInt>(
ConstantExpr::getFCmp(FCmpInst::FCMP_OLT, V1, V2));
if (R && !R->isZero())
return FCmpInst::FCMP_OLT;
R = dyn_cast<ConstantInt>(
ConstantExpr::getFCmp(FCmpInst::FCMP_OGT, V1, V2));
if (R && !R->isZero())
return FCmpInst::FCMP_OGT;
// Nothing more we can do
return FCmpInst::BAD_FCMP_PREDICATE;
}
// If the first operand is simple and second is ConstantExpr, swap operands.
FCmpInst::Predicate SwappedRelation = evaluateFCmpRelation(V2, V1);
if (SwappedRelation != FCmpInst::BAD_FCMP_PREDICATE)
return FCmpInst::getSwappedPredicate(SwappedRelation);
} else {
// Ok, the LHS is known to be a constantexpr. The RHS can be any of a
// constantexpr or a simple constant.
ConstantExpr *CE1 = cast<ConstantExpr>(V1);
switch (CE1->getOpcode()) {
case Instruction::FPTrunc:
case Instruction::FPExt:
case Instruction::UIToFP:
case Instruction::SIToFP:
// We might be able to do something with these but we don't right now.
break;
default:
break;
}
}
// There are MANY other foldings that we could perform here. They will
// probably be added on demand, as they seem needed.
return FCmpInst::BAD_FCMP_PREDICATE;
}
static ICmpInst::Predicate areGlobalsPotentiallyEqual(const GlobalValue *GV1,
const GlobalValue *GV2) {
auto isGlobalUnsafeForEquality = [](const GlobalValue *GV) {
if (GV->hasExternalWeakLinkage() || GV->hasWeakAnyLinkage())
return true;
if (const auto *GVar = dyn_cast<GlobalVariable>(GV)) {
Type *Ty = GVar->getValueType();
// A global with opaque type might end up being zero sized.
if (!Ty->isSized())
return true;
// A global with an empty type might lie at the address of any other
// global.
if (Ty->isEmptyTy())
return true;
}
return false;
};
// Don't try to decide equality of aliases.
if (!isa<GlobalAlias>(GV1) && !isa<GlobalAlias>(GV2))
if (!isGlobalUnsafeForEquality(GV1) && !isGlobalUnsafeForEquality(GV2))
return ICmpInst::ICMP_NE;
return ICmpInst::BAD_ICMP_PREDICATE;
}
/// evaluateICmpRelation - This function determines if there is anything we can
/// decide about the two constants provided. This doesn't need to handle simple
/// things like integer comparisons, but should instead handle ConstantExprs
/// and GlobalValues. If we can determine that the two constants have a
/// particular relation to each other, we should return the corresponding ICmp
/// predicate, otherwise return ICmpInst::BAD_ICMP_PREDICATE.
///
/// To simplify this code we canonicalize the relation so that the first
/// operand is always the most "complex" of the two. We consider simple
/// constants (like ConstantInt) to be the simplest, followed by
/// GlobalValues, followed by ConstantExpr's (the most complex).
///
static ICmpInst::Predicate evaluateICmpRelation(Constant *V1, Constant *V2,
bool isSigned) {
assert(V1->getType() == V2->getType() &&
"Cannot compare different types of values!");
if (V1 == V2) return ICmpInst::ICMP_EQ;
if (!isa<ConstantExpr>(V1) && !isa<GlobalValue>(V1) &&
!isa<BlockAddress>(V1)) {
if (!isa<GlobalValue>(V2) && !isa<ConstantExpr>(V2) &&
!isa<BlockAddress>(V2)) {
// We distilled this down to a simple case, use the standard constant
// folder.
ConstantInt *R = nullptr;
ICmpInst::Predicate pred = ICmpInst::ICMP_EQ;
R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, V1, V2));
if (R && !R->isZero())
return pred;
pred = isSigned ? ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT;
R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, V1, V2));
if (R && !R->isZero())
return pred;
pred = isSigned ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT;
R = dyn_cast<ConstantInt>(ConstantExpr::getICmp(pred, V1, V2));
if (R && !R->isZero())
return pred;
// If we couldn't figure it out, bail.
return ICmpInst::BAD_ICMP_PREDICATE;
}
// If the first operand is simple, swap operands.
ICmpInst::Predicate SwappedRelation =
evaluateICmpRelation(V2, V1, isSigned);
if (SwappedRelation != ICmpInst::BAD_ICMP_PREDICATE)
return ICmpInst::getSwappedPredicate(SwappedRelation);
} else if (const GlobalValue *GV = dyn_cast<GlobalValue>(V1)) {
if (isa<ConstantExpr>(V2)) { // Swap as necessary.
ICmpInst::Predicate SwappedRelation =
evaluateICmpRelation(V2, V1, isSigned);
if (SwappedRelation != ICmpInst::BAD_ICMP_PREDICATE)
return ICmpInst::getSwappedPredicate(SwappedRelation);
return ICmpInst::BAD_ICMP_PREDICATE;
}
// Now we know that the RHS is a GlobalValue, BlockAddress or simple
// constant (which, since the types must match, means that it's a
// ConstantPointerNull).
if (const GlobalValue *GV2 = dyn_cast<GlobalValue>(V2)) {
return areGlobalsPotentiallyEqual(GV, GV2);
} else if (isa<BlockAddress>(V2)) {
return ICmpInst::ICMP_NE; // Globals never equal labels.
} else {
assert(isa<ConstantPointerNull>(V2) && "Canonicalization guarantee!");
// GlobalVals can never be null unless they have external weak linkage.
// We don't try to evaluate aliases here.
if (!GV->hasExternalWeakLinkage() && !isa<GlobalAlias>(GV))
return ICmpInst::ICMP_NE;
}
} else if (const BlockAddress *BA = dyn_cast<BlockAddress>(V1)) {
if (isa<ConstantExpr>(V2)) { // Swap as necessary.
ICmpInst::Predicate SwappedRelation =
evaluateICmpRelation(V2, V1, isSigned);
if (SwappedRelation != ICmpInst::BAD_ICMP_PREDICATE)
return ICmpInst::getSwappedPredicate(SwappedRelation);
return ICmpInst::BAD_ICMP_PREDICATE;
}
// Now we know that the RHS is a GlobalValue, BlockAddress or simple
// constant (which, since the types must match, means that it is a
// ConstantPointerNull).
if (const BlockAddress *BA2 = dyn_cast<BlockAddress>(V2)) {
// Block address in another function can't equal this one, but block
// addresses in the current function might be the same if blocks are
// empty.
if (BA2->getFunction() != BA->getFunction())
return ICmpInst::ICMP_NE;
} else {
// Block addresses aren't null, don't equal the address of globals.
assert((isa<ConstantPointerNull>(V2) || isa<GlobalValue>(V2)) &&
"Canonicalization guarantee!");
return ICmpInst::ICMP_NE;
}
} else {
// Ok, the LHS is known to be a constantexpr. The RHS can be any of a
// constantexpr, a global, block address, or a simple constant.
ConstantExpr *CE1 = cast<ConstantExpr>(V1);
Constant *CE1Op0 = CE1->getOperand(0);
switch (CE1->getOpcode()) {
case Instruction::Trunc:
case Instruction::FPTrunc:
case Instruction::FPExt:
case Instruction::FPToUI:
case Instruction::FPToSI:
break; // We can't evaluate floating point casts or truncations.
case Instruction::UIToFP:
case Instruction::SIToFP:
case Instruction::BitCast:
case Instruction::ZExt:
case Instruction::SExt:
// If the cast is not actually changing bits, and the second operand is a
// null pointer, do the comparison with the pre-casted value.
if (V2->isNullValue() &&
(CE1->getType()->isPointerTy() || CE1->getType()->isIntegerTy())) {
if (CE1->getOpcode() == Instruction::ZExt) isSigned = false;
if (CE1->getOpcode() == Instruction::SExt) isSigned = true;
return evaluateICmpRelation(CE1Op0,
Constant::getNullValue(CE1Op0->getType()),
isSigned);
}
break;
case Instruction::GetElementPtr: {
GEPOperator *CE1GEP = cast<GEPOperator>(CE1);
// Ok, since this is a getelementptr, we know that the constant has a
// pointer type. Check the various cases.
if (isa<ConstantPointerNull>(V2)) {
// If we are comparing a GEP to a null pointer, check to see if the base
// of the GEP equals the null pointer.
if (const GlobalValue *GV = dyn_cast<GlobalValue>(CE1Op0)) {
if (GV->hasExternalWeakLinkage())
// Weak linkage GVals could be zero or not. We're comparing that
// to null pointer so its greater-or-equal
return isSigned ? ICmpInst::ICMP_SGE : ICmpInst::ICMP_UGE;
else
// If its not weak linkage, the GVal must have a non-zero address
// so the result is greater-than
return isSigned ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT;
} else if (isa<ConstantPointerNull>(CE1Op0)) {
// If we are indexing from a null pointer, check to see if we have any
// non-zero indices.
for (unsigned i = 1, e = CE1->getNumOperands(); i != e; ++i)
if (!CE1->getOperand(i)->isNullValue())
// Offsetting from null, must not be equal.
return isSigned ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT;
// Only zero indexes from null, must still be zero.
return ICmpInst::ICMP_EQ;
}
// Otherwise, we can't really say if the first operand is null or not.
} else if (const GlobalValue *GV2 = dyn_cast<GlobalValue>(V2)) {
if (isa<ConstantPointerNull>(CE1Op0)) {
if (GV2->hasExternalWeakLinkage())
// Weak linkage GVals could be zero or not. We're comparing it to
// a null pointer, so its less-or-equal
return isSigned ? ICmpInst::ICMP_SLE : ICmpInst::ICMP_ULE;
else
// If its not weak linkage, the GVal must have a non-zero address
// so the result is less-than
return isSigned ? ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT;
} else if (const GlobalValue *GV = dyn_cast<GlobalValue>(CE1Op0)) {
if (GV == GV2) {
// If this is a getelementptr of the same global, then it must be
// different. Because the types must match, the getelementptr could
// only have at most one index, and because we fold getelementptr's
// with a single zero index, it must be nonzero.
assert(CE1->getNumOperands() == 2 &&
!CE1->getOperand(1)->isNullValue() &&
"Surprising getelementptr!");
return isSigned ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT;
} else {
if (CE1GEP->hasAllZeroIndices())
return areGlobalsPotentiallyEqual(GV, GV2);
return ICmpInst::BAD_ICMP_PREDICATE;
}
}
} else {
ConstantExpr *CE2 = cast<ConstantExpr>(V2);
Constant *CE2Op0 = CE2->getOperand(0);
// There are MANY other foldings that we could perform here. They will
// probably be added on demand, as they seem needed.
switch (CE2->getOpcode()) {
default: break;
case Instruction::GetElementPtr:
// By far the most common case to handle is when the base pointers are
// obviously to the same global.
if (isa<GlobalValue>(CE1Op0) && isa<GlobalValue>(CE2Op0)) {
// Don't know relative ordering, but check for inequality.
if (CE1Op0 != CE2Op0) {
GEPOperator *CE2GEP = cast<GEPOperator>(CE2);
if (CE1GEP->hasAllZeroIndices() && CE2GEP->hasAllZeroIndices())
return areGlobalsPotentiallyEqual(cast<GlobalValue>(CE1Op0),
cast<GlobalValue>(CE2Op0));
return ICmpInst::BAD_ICMP_PREDICATE;
}
// Ok, we know that both getelementptr instructions are based on the
// same global. From this, we can precisely determine the relative
// ordering of the resultant pointers.
unsigned i = 1;
// The logic below assumes that the result of the comparison
// can be determined by finding the first index that differs.
// This doesn't work if there is over-indexing in any
// subsequent indices, so check for that case first.
if (!CE1->isGEPWithNoNotionalOverIndexing() ||
!CE2->isGEPWithNoNotionalOverIndexing())
return ICmpInst::BAD_ICMP_PREDICATE; // Might be equal.
// Compare all of the operands the GEP's have in common.
gep_type_iterator GTI = gep_type_begin(CE1);
for (;i != CE1->getNumOperands() && i != CE2->getNumOperands();
++i, ++GTI)
switch (IdxCompare(CE1->getOperand(i),
CE2->getOperand(i), GTI.getIndexedType())) {
case -1: return isSigned ? ICmpInst::ICMP_SLT:ICmpInst::ICMP_ULT;
case 1: return isSigned ? ICmpInst::ICMP_SGT:ICmpInst::ICMP_UGT;
case -2: return ICmpInst::BAD_ICMP_PREDICATE;
}
// Ok, we ran out of things they have in common. If any leftovers
// are non-zero then we have a difference, otherwise we are equal.
for (; i < CE1->getNumOperands(); ++i)
if (!CE1->getOperand(i)->isNullValue()) {
if (isa<ConstantInt>(CE1->getOperand(i)))
return isSigned ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT;
else
return ICmpInst::BAD_ICMP_PREDICATE; // Might be equal.
}
for (; i < CE2->getNumOperands(); ++i)
if (!CE2->getOperand(i)->isNullValue()) {
if (isa<ConstantInt>(CE2->getOperand(i)))
return isSigned ? ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT;
else
return ICmpInst::BAD_ICMP_PREDICATE; // Might be equal.
}
return ICmpInst::ICMP_EQ;
}
}
}
} break;
default:
break;
}
}
return ICmpInst::BAD_ICMP_PREDICATE;
}
Constant *llvm::ConstantFoldCompareInstruction(unsigned short pred,
Constant *C1, Constant *C2) {
Type *ResultTy;
if (VectorType *VT = dyn_cast<VectorType>(C1->getType()))
ResultTy = VectorType::get(Type::getInt1Ty(C1->getContext()),
VT->getNumElements());
else
ResultTy = Type::getInt1Ty(C1->getContext());
// Fold FCMP_FALSE/FCMP_TRUE unconditionally.
if (pred == FCmpInst::FCMP_FALSE)
return Constant::getNullValue(ResultTy);
if (pred == FCmpInst::FCMP_TRUE)
return Constant::getAllOnesValue(ResultTy);
// Handle some degenerate cases first
if (isa<UndefValue>(C1) || isa<UndefValue>(C2)) {
CmpInst::Predicate Predicate = CmpInst::Predicate(pred);
bool isIntegerPredicate = ICmpInst::isIntPredicate(Predicate);
// For EQ and NE, we can always pick a value for the undef to make the
// predicate pass or fail, so we can return undef.
// Also, if both operands are undef, we can return undef for int comparison.
if (ICmpInst::isEquality(Predicate) || (isIntegerPredicate && C1 == C2))
return UndefValue::get(ResultTy);
// Otherwise, for integer compare, pick the same value as the non-undef
// operand, and fold it to true or false.
if (isIntegerPredicate)
return ConstantInt::get(ResultTy, CmpInst::isTrueWhenEqual(pred));
// Choosing NaN for the undef will always make unordered comparison succeed
// and ordered comparison fails.
return ConstantInt::get(ResultTy, CmpInst::isUnordered(Predicate));
}
// icmp eq/ne(null,GV) -> false/true
if (C1->isNullValue()) {
if (const GlobalValue *GV = dyn_cast<GlobalValue>(C2))
// Don't try to evaluate aliases. External weak GV can be null.
if (!isa<GlobalAlias>(GV) && !GV->hasExternalWeakLinkage()) {
if (pred == ICmpInst::ICMP_EQ)
return ConstantInt::getFalse(C1->getContext());
else if (pred == ICmpInst::ICMP_NE)
return ConstantInt::getTrue(C1->getContext());
}
// icmp eq/ne(GV,null) -> false/true
} else if (C2->isNullValue()) {
if (const GlobalValue *GV = dyn_cast<GlobalValue>(C1))
// Don't try to evaluate aliases. External weak GV can be null.
if (!isa<GlobalAlias>(GV) && !GV->hasExternalWeakLinkage()) {
if (pred == ICmpInst::ICMP_EQ)
return ConstantInt::getFalse(C1->getContext());
else if (pred == ICmpInst::ICMP_NE)
return ConstantInt::getTrue(C1->getContext());
}
}
// If the comparison is a comparison between two i1's, simplify it.
if (C1->getType()->isIntegerTy(1)) {
switch(pred) {
case ICmpInst::ICMP_EQ:
if (isa<ConstantInt>(C2))
return ConstantExpr::getXor(C1, ConstantExpr::getNot(C2));
return ConstantExpr::getXor(ConstantExpr::getNot(C1), C2);
case ICmpInst::ICMP_NE:
return ConstantExpr::getXor(C1, C2);
default:
break;
}
}
if (isa<ConstantInt>(C1) && isa<ConstantInt>(C2)) {
APInt V1 = cast<ConstantInt>(C1)->getValue();
APInt V2 = cast<ConstantInt>(C2)->getValue();
switch (pred) {
default: llvm_unreachable("Invalid ICmp Predicate");
case ICmpInst::ICMP_EQ: return ConstantInt::get(ResultTy, V1 == V2);
case ICmpInst::ICMP_NE: return ConstantInt::get(ResultTy, V1 != V2);
case ICmpInst::ICMP_SLT: return ConstantInt::get(ResultTy, V1.slt(V2));
case ICmpInst::ICMP_SGT: return ConstantInt::get(ResultTy, V1.sgt(V2));
case ICmpInst::ICMP_SLE: return ConstantInt::get(ResultTy, V1.sle(V2));
case ICmpInst::ICMP_SGE: return ConstantInt::get(ResultTy, V1.sge(V2));
case ICmpInst::ICMP_ULT: return ConstantInt::get(ResultTy, V1.ult(V2));
case ICmpInst::ICMP_UGT: return ConstantInt::get(ResultTy, V1.ugt(V2));
case ICmpInst::ICMP_ULE: return ConstantInt::get(ResultTy, V1.ule(V2));
case ICmpInst::ICMP_UGE: return ConstantInt::get(ResultTy, V1.uge(V2));
}
} else if (isa<ConstantFP>(C1) && isa<ConstantFP>(C2)) {
APFloat C1V = cast<ConstantFP>(C1)->getValueAPF();
APFloat C2V = cast<ConstantFP>(C2)->getValueAPF();
APFloat::cmpResult R = C1V.compare(C2V);
switch (pred) {
default: llvm_unreachable("Invalid FCmp Predicate");
case FCmpInst::FCMP_FALSE: return Constant::getNullValue(ResultTy);
case FCmpInst::FCMP_TRUE: return Constant::getAllOnesValue(ResultTy);
case FCmpInst::FCMP_UNO:
return ConstantInt::get(ResultTy, R==APFloat::cmpUnordered);
case FCmpInst::FCMP_ORD:
return ConstantInt::get(ResultTy, R!=APFloat::cmpUnordered);
case FCmpInst::FCMP_UEQ:
return ConstantInt::get(ResultTy, R==APFloat::cmpUnordered ||
R==APFloat::cmpEqual);
case FCmpInst::FCMP_OEQ:
return ConstantInt::get(ResultTy, R==APFloat::cmpEqual);
case FCmpInst::FCMP_UNE:
return ConstantInt::get(ResultTy, R!=APFloat::cmpEqual);
case FCmpInst::FCMP_ONE:
return ConstantInt::get(ResultTy, R==APFloat::cmpLessThan ||
R==APFloat::cmpGreaterThan);
case FCmpInst::FCMP_ULT:
return ConstantInt::get(ResultTy, R==APFloat::cmpUnordered ||
R==APFloat::cmpLessThan);
case FCmpInst::FCMP_OLT:
return ConstantInt::get(ResultTy, R==APFloat::cmpLessThan);
case FCmpInst::FCMP_UGT:
return ConstantInt::get(ResultTy, R==APFloat::cmpUnordered ||
R==APFloat::cmpGreaterThan);
case FCmpInst::FCMP_OGT:
return ConstantInt::get(ResultTy, R==APFloat::cmpGreaterThan);
case FCmpInst::FCMP_ULE:
return ConstantInt::get(ResultTy, R!=APFloat::cmpGreaterThan);
case FCmpInst::FCMP_OLE:
return ConstantInt::get(ResultTy, R==APFloat::cmpLessThan ||
R==APFloat::cmpEqual);
case FCmpInst::FCMP_UGE:
return ConstantInt::get(ResultTy, R!=APFloat::cmpLessThan);
case FCmpInst::FCMP_OGE:
return ConstantInt::get(ResultTy, R==APFloat::cmpGreaterThan ||
R==APFloat::cmpEqual);
}
} else if (C1->getType()->isVectorTy()) {
// If we can constant fold the comparison of each element, constant fold
// the whole vector comparison.
SmallVector<Constant*, 4> ResElts;
Type *Ty = IntegerType::get(C1->getContext(), 32);
// Compare the elements, producing an i1 result or constant expr.
for (unsigned i = 0, e = C1->getType()->getVectorNumElements(); i != e;++i){
Constant *C1E =
ConstantExpr::getExtractElement(C1, ConstantInt::get(Ty, i));
Constant *C2E =
ConstantExpr::getExtractElement(C2, ConstantInt::get(Ty, i));
ResElts.push_back(ConstantExpr::getCompare(pred, C1E, C2E));
}
return ConstantVector::get(ResElts);
}
if (C1->getType()->isFloatingPointTy() &&
// Only call evaluateFCmpRelation if we have a constant expr to avoid
// infinite recursive loop
(isa<ConstantExpr>(C1) || isa<ConstantExpr>(C2))) {
int Result = -1; // -1 = unknown, 0 = known false, 1 = known true.
switch (evaluateFCmpRelation(C1, C2)) {
default: llvm_unreachable("Unknown relation!");
case FCmpInst::FCMP_UNO:
case FCmpInst::FCMP_ORD:
case FCmpInst::FCMP_UEQ:
case FCmpInst::FCMP_UNE:
case FCmpInst::FCMP_ULT:
case FCmpInst::FCMP_UGT:
case FCmpInst::FCMP_ULE:
case FCmpInst::FCMP_UGE:
case FCmpInst::FCMP_TRUE:
case FCmpInst::FCMP_FALSE:
case FCmpInst::BAD_FCMP_PREDICATE:
break; // Couldn't determine anything about these constants.
case FCmpInst::FCMP_OEQ: // We know that C1 == C2
Result = (pred == FCmpInst::FCMP_UEQ || pred == FCmpInst::FCMP_OEQ ||
pred == FCmpInst::FCMP_ULE || pred == FCmpInst::FCMP_OLE ||
pred == FCmpInst::FCMP_UGE || pred == FCmpInst::FCMP_OGE);
break;
case FCmpInst::FCMP_OLT: // We know that C1 < C2
Result = (pred == FCmpInst::FCMP_UNE || pred == FCmpInst::FCMP_ONE ||
pred == FCmpInst::FCMP_ULT || pred == FCmpInst::FCMP_OLT ||
pred == FCmpInst::FCMP_ULE || pred == FCmpInst::FCMP_OLE);
break;
case FCmpInst::FCMP_OGT: // We know that C1 > C2
Result = (pred == FCmpInst::FCMP_UNE || pred == FCmpInst::FCMP_ONE ||
pred == FCmpInst::FCMP_UGT || pred == FCmpInst::FCMP_OGT ||
pred == FCmpInst::FCMP_UGE || pred == FCmpInst::FCMP_OGE);
break;
case FCmpInst::FCMP_OLE: // We know that C1 <= C2
// We can only partially decide this relation.
if (pred == FCmpInst::FCMP_UGT || pred == FCmpInst::FCMP_OGT)
Result = 0;
else if (pred == FCmpInst::FCMP_ULT || pred == FCmpInst::FCMP_OLT)
Result = 1;
break;
case FCmpInst::FCMP_OGE: // We known that C1 >= C2
// We can only partially decide this relation.
if (pred == FCmpInst::FCMP_ULT || pred == FCmpInst::FCMP_OLT)
Result = 0;
else if (pred == FCmpInst::FCMP_UGT || pred == FCmpInst::FCMP_OGT)
Result = 1;
break;
case FCmpInst::FCMP_ONE: // We know that C1 != C2
// We can only partially decide this relation.
if (pred == FCmpInst::FCMP_OEQ || pred == FCmpInst::FCMP_UEQ)
Result = 0;
else if (pred == FCmpInst::FCMP_ONE || pred == FCmpInst::FCMP_UNE)
Result = 1;
break;
}
// If we evaluated the result, return it now.
if (Result != -1)
return ConstantInt::get(ResultTy, Result);
} else {
// Evaluate the relation between the two constants, per the predicate.
int Result = -1; // -1 = unknown, 0 = known false, 1 = known true.
switch (evaluateICmpRelation(C1, C2, CmpInst::isSigned(pred))) {
default: llvm_unreachable("Unknown relational!");
case ICmpInst::BAD_ICMP_PREDICATE:
break; // Couldn't determine anything about these constants.
case ICmpInst::ICMP_EQ: // We know the constants are equal!
// If we know the constants are equal, we can decide the result of this
// computation precisely.
Result = ICmpInst::isTrueWhenEqual((ICmpInst::Predicate)pred);
break;
case ICmpInst::ICMP_ULT:
switch (pred) {
case ICmpInst::ICMP_ULT: case ICmpInst::ICMP_NE: case ICmpInst::ICMP_ULE:
Result = 1; break;
case ICmpInst::ICMP_UGT: case ICmpInst::ICMP_EQ: case ICmpInst::ICMP_UGE:
Result = 0; break;
}
break;
case ICmpInst::ICMP_SLT:
switch (pred) {
case ICmpInst::ICMP_SLT: case ICmpInst::ICMP_NE: case ICmpInst::ICMP_SLE:
Result = 1; break;
case ICmpInst::ICMP_SGT: case ICmpInst::ICMP_EQ: case ICmpInst::ICMP_SGE:
Result = 0; break;
}
break;
case ICmpInst::ICMP_UGT:
switch (pred) {
case ICmpInst::ICMP_UGT: case ICmpInst::ICMP_NE: case ICmpInst::ICMP_UGE:
Result = 1; break;
case ICmpInst::ICMP_ULT: case ICmpInst::ICMP_EQ: case ICmpInst::ICMP_ULE:
Result = 0; break;
}
break;
case ICmpInst::ICMP_SGT:
switch (pred) {
case ICmpInst::ICMP_SGT: case ICmpInst::ICMP_NE: case ICmpInst::ICMP_SGE:
Result = 1; break;
case ICmpInst::ICMP_SLT: case ICmpInst::ICMP_EQ: case ICmpInst::ICMP_SLE:
Result = 0; break;
}
break;
case ICmpInst::ICMP_ULE:
if (pred == ICmpInst::ICMP_UGT) Result = 0;
if (pred == ICmpInst::ICMP_ULT || pred == ICmpInst::ICMP_ULE) Result = 1;
break;
case ICmpInst::ICMP_SLE:
if (pred == ICmpInst::ICMP_SGT) Result = 0;
if (pred == ICmpInst::ICMP_SLT || pred == ICmpInst::ICMP_SLE) Result = 1;
break;
case ICmpInst::ICMP_UGE:
if (pred == ICmpInst::ICMP_ULT) Result = 0;
if (pred == ICmpInst::ICMP_UGT || pred == ICmpInst::ICMP_UGE) Result = 1;
break;
case ICmpInst::ICMP_SGE:
if (pred == ICmpInst::ICMP_SLT) Result = 0;
if (pred == ICmpInst::ICMP_SGT || pred == ICmpInst::ICMP_SGE) Result = 1;
break;
case ICmpInst::ICMP_NE:
if (pred == ICmpInst::ICMP_EQ) Result = 0;
if (pred == ICmpInst::ICMP_NE) Result = 1;
break;
}
// If we evaluated the result, return it now.
if (Result != -1)
return ConstantInt::get(ResultTy, Result);
// If the right hand side is a bitcast, try using its inverse to simplify
// it by moving it to the left hand side. We can't do this if it would turn
// a vector compare into a scalar compare or visa versa.
if (ConstantExpr *CE2 = dyn_cast<ConstantExpr>(C2)) {
Constant *CE2Op0 = CE2->getOperand(0);
if (CE2->getOpcode() == Instruction::BitCast &&
CE2->getType()->isVectorTy() == CE2Op0->getType()->isVectorTy()) {
Constant *Inverse = ConstantExpr::getBitCast(C1, CE2Op0->getType());
return ConstantExpr::getICmp(pred, Inverse, CE2Op0);
}
}
// If the left hand side is an extension, try eliminating it.
if (ConstantExpr *CE1 = dyn_cast<ConstantExpr>(C1)) {
if ((CE1->getOpcode() == Instruction::SExt && ICmpInst::isSigned(pred)) ||
(CE1->getOpcode() == Instruction::ZExt && !ICmpInst::isSigned(pred))){
Constant *CE1Op0 = CE1->getOperand(0);
Constant *CE1Inverse = ConstantExpr::getTrunc(CE1, CE1Op0->getType());
if (CE1Inverse == CE1Op0) {
// Check whether we can safely truncate the right hand side.
Constant *C2Inverse = ConstantExpr::getTrunc(C2, CE1Op0->getType());
if (ConstantExpr::getCast(CE1->getOpcode(), C2Inverse,
C2->getType()) == C2)
return ConstantExpr::getICmp(pred, CE1Inverse, C2Inverse);
}
}
}
if ((!isa<ConstantExpr>(C1) && isa<ConstantExpr>(C2)) ||
(C1->isNullValue() && !C2->isNullValue())) {
// If C2 is a constant expr and C1 isn't, flip them around and fold the
// other way if possible.
// Also, if C1 is null and C2 isn't, flip them around.
pred = ICmpInst::getSwappedPredicate((ICmpInst::Predicate)pred);
return ConstantExpr::getICmp(pred, C2, C1);
}
}
return nullptr;
}
/// isInBoundsIndices - Test whether the given sequence of *normalized* indices
/// is "inbounds".
template<typename IndexTy>
static bool isInBoundsIndices(ArrayRef<IndexTy> Idxs) {
// No indices means nothing that could be out of bounds.
if (Idxs.empty()) return true;
// If the first index is zero, it's in bounds.
if (cast<Constant>(Idxs[0])->isNullValue()) return true;
// If the first index is one and all the rest are zero, it's in bounds,
// by the one-past-the-end rule.
if (!cast<ConstantInt>(Idxs[0])->isOne())
return false;
for (unsigned i = 1, e = Idxs.size(); i != e; ++i)
if (!cast<Constant>(Idxs[i])->isNullValue())
return false;
return true;
}
/// \brief Test whether a given ConstantInt is in-range for a SequentialType.
static bool isIndexInRangeOfSequentialType(const SequentialType *STy,
const ConstantInt *CI) {
if (const PointerType *PTy = dyn_cast<PointerType>(STy))
// Only handle pointers to sized types, not pointers to functions.
return PTy->getElementType()->isSized();
uint64_t NumElements = 0;
// Determine the number of elements in our sequential type.
if (const ArrayType *ATy = dyn_cast<ArrayType>(STy))
NumElements = ATy->getNumElements();
else if (const VectorType *VTy = dyn_cast<VectorType>(STy))
NumElements = VTy->getNumElements();
assert((isa<ArrayType>(STy) || NumElements > 0) &&
"didn't expect non-array type to have zero elements!");
// We cannot bounds check the index if it doesn't fit in an int64_t.
if (CI->getValue().getActiveBits() > 64)
return false;
// A negative index or an index past the end of our sequential type is
// considered out-of-range.
int64_t IndexVal = CI->getSExtValue();
if (IndexVal < 0 || (NumElements > 0 && (uint64_t)IndexVal >= NumElements))
return false;
// Otherwise, it is in-range.
return true;
}
template<typename IndexTy>
static Constant *ConstantFoldGetElementPtrImpl(Type *PointeeTy, Constant *C,
bool inBounds,
ArrayRef<IndexTy> Idxs) {
if (Idxs.empty()) return C;
Constant *Idx0 = cast<Constant>(Idxs[0]);
if ((Idxs.size() == 1 && Idx0->isNullValue()))
return C;
if (isa<UndefValue>(C)) {
PointerType *Ptr = cast<PointerType>(C->getType());
Type *Ty = GetElementPtrInst::getIndexedType(
cast<PointerType>(Ptr->getScalarType())->getElementType(), Idxs);
assert(Ty && "Invalid indices for GEP!");
return UndefValue::get(PointerType::get(Ty, Ptr->getAddressSpace()));
}
if (C->isNullValue()) {
bool isNull = true;
for (unsigned i = 0, e = Idxs.size(); i != e; ++i)
if (!cast<Constant>(Idxs[i])->isNullValue()) {
isNull = false;
break;
}
if (isNull) {
PointerType *Ptr = cast<PointerType>(C->getType());
Type *Ty = GetElementPtrInst::getIndexedType(
cast<PointerType>(Ptr->getScalarType())->getElementType(), Idxs);
assert(Ty && "Invalid indices for GEP!");
return ConstantPointerNull::get(PointerType::get(Ty,
Ptr->getAddressSpace()));
}
}
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
// Combine Indices - If the source pointer to this getelementptr instruction
// is a getelementptr instruction, combine the indices of the two
// getelementptr instructions into a single instruction.
//
if (CE->getOpcode() == Instruction::GetElementPtr) {
Type *LastTy = nullptr;
for (gep_type_iterator I = gep_type_begin(CE), E = gep_type_end(CE);
I != E; ++I)
LastTy = *I;
// We cannot combine indices if doing so would take us outside of an
// array or vector. Doing otherwise could trick us if we evaluated such a
// GEP as part of a load.
//
// e.g. Consider if the original GEP was:
// i8* getelementptr ({ [2 x i8], i32, i8, [3 x i8] }* @main.c,
// i32 0, i32 0, i64 0)
//
// If we then tried to offset it by '8' to get to the third element,
// an i8, we should *not* get:
// i8* getelementptr ({ [2 x i8], i32, i8, [3 x i8] }* @main.c,
// i32 0, i32 0, i64 8)
//
// This GEP tries to index array element '8 which runs out-of-bounds.
// Subsequent evaluation would get confused and produce erroneous results.
//
// The following prohibits such a GEP from being formed by checking to see
// if the index is in-range with respect to an array or vector.
bool PerformFold = false;
if (Idx0->isNullValue())
PerformFold = true;
else if (SequentialType *STy = dyn_cast_or_null<SequentialType>(LastTy))
if (ConstantInt *CI = dyn_cast<ConstantInt>(Idx0))
PerformFold = isIndexInRangeOfSequentialType(STy, CI);
if (PerformFold) {
SmallVector<Value*, 16> NewIndices;
NewIndices.reserve(Idxs.size() + CE->getNumOperands());
NewIndices.append(CE->op_begin() + 1, CE->op_end() - 1);
// Add the last index of the source with the first index of the new GEP.
// Make sure to handle the case when they are actually different types.
Constant *Combined = CE->getOperand(CE->getNumOperands()-1);
// Otherwise it must be an array.
if (!Idx0->isNullValue()) {
Type *IdxTy = Combined->getType();
if (IdxTy != Idx0->getType()) {
unsigned CommonExtendedWidth =
std::max(IdxTy->getIntegerBitWidth(),
Idx0->getType()->getIntegerBitWidth());
CommonExtendedWidth = std::max(CommonExtendedWidth, 64U);
Type *CommonTy =
Type::getIntNTy(IdxTy->getContext(), CommonExtendedWidth);
Constant *C1 = ConstantExpr::getSExtOrBitCast(Idx0, CommonTy);
Constant *C2 = ConstantExpr::getSExtOrBitCast(Combined, CommonTy);
Combined = ConstantExpr::get(Instruction::Add, C1, C2);
} else {
Combined =
ConstantExpr::get(Instruction::Add, Idx0, Combined);
}
}
NewIndices.push_back(Combined);
NewIndices.append(Idxs.begin() + 1, Idxs.end());
return ConstantExpr::getGetElementPtr(
cast<GEPOperator>(CE)->getSourceElementType(), CE->getOperand(0),
NewIndices, inBounds && cast<GEPOperator>(CE)->isInBounds());
}
}
// Attempt to fold casts to the same type away. For example, folding:
//
// i32* getelementptr ([2 x i32]* bitcast ([3 x i32]* %X to [2 x i32]*),
// i64 0, i64 0)
// into:
//
// i32* getelementptr ([3 x i32]* %X, i64 0, i64 0)
//
// Don't fold if the cast is changing address spaces.
if (CE->isCast() && Idxs.size() > 1 && Idx0->isNullValue()) {
PointerType *SrcPtrTy =
dyn_cast<PointerType>(CE->getOperand(0)->getType());
PointerType *DstPtrTy = dyn_cast<PointerType>(CE->getType());
if (SrcPtrTy && DstPtrTy) {
ArrayType *SrcArrayTy =
dyn_cast<ArrayType>(SrcPtrTy->getElementType());
ArrayType *DstArrayTy =
dyn_cast<ArrayType>(DstPtrTy->getElementType());
if (SrcArrayTy && DstArrayTy
&& SrcArrayTy->getElementType() == DstArrayTy->getElementType()
&& SrcPtrTy->getAddressSpace() == DstPtrTy->getAddressSpace())
return ConstantExpr::getGetElementPtr(
SrcArrayTy, (Constant *)CE->getOperand(0), Idxs, inBounds);
}
}
}
// Check to see if any array indices are not within the corresponding
// notional array or vector bounds. If so, try to determine if they can be
// factored out into preceding dimensions.
SmallVector<Constant *, 8> NewIdxs;
Type *Ty = PointeeTy;
Type *Prev = C->getType();
bool Unknown = !isa<ConstantInt>(Idxs[0]);
for (unsigned i = 1, e = Idxs.size(); i != e;
Prev = Ty, Ty = cast<CompositeType>(Ty)->getTypeAtIndex(Idxs[i]), ++i) {
if (ConstantInt *CI = dyn_cast<ConstantInt>(Idxs[i])) {
if (isa<ArrayType>(Ty) || isa<VectorType>(Ty))
if (CI->getSExtValue() > 0 &&
!isIndexInRangeOfSequentialType(cast<SequentialType>(Ty), CI)) {
if (isa<SequentialType>(Prev)) {
// It's out of range, but we can factor it into the prior
// dimension.
NewIdxs.resize(Idxs.size());
uint64_t NumElements = 0;
if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty))
NumElements = ATy->getNumElements();
else
NumElements = cast<VectorType>(Ty)->getNumElements();
ConstantInt *Factor = ConstantInt::get(CI->getType(), NumElements);
NewIdxs[i] = ConstantExpr::getSRem(CI, Factor);
Constant *PrevIdx = cast<Constant>(Idxs[i-1]);
Constant *Div = ConstantExpr::getSDiv(CI, Factor);
unsigned CommonExtendedWidth =
std::max(PrevIdx->getType()->getIntegerBitWidth(),
Div->getType()->getIntegerBitWidth());
CommonExtendedWidth = std::max(CommonExtendedWidth, 64U);
// Before adding, extend both operands to i64 to avoid
// overflow trouble.
if (!PrevIdx->getType()->isIntegerTy(CommonExtendedWidth))
PrevIdx = ConstantExpr::getSExt(
PrevIdx,
Type::getIntNTy(Div->getContext(), CommonExtendedWidth));
if (!Div->getType()->isIntegerTy(CommonExtendedWidth))
Div = ConstantExpr::getSExt(
Div, Type::getIntNTy(Div->getContext(), CommonExtendedWidth));
NewIdxs[i-1] = ConstantExpr::getAdd(PrevIdx, Div);
} else {
// It's out of range, but the prior dimension is a struct
// so we can't do anything about it.
Unknown = true;
}
}
} else {
// We don't know if it's in range or not.
Unknown = true;
}
}
// If we did any factoring, start over with the adjusted indices.
if (!NewIdxs.empty()) {
for (unsigned i = 0, e = Idxs.size(); i != e; ++i)
if (!NewIdxs[i]) NewIdxs[i] = cast<Constant>(Idxs[i]);
return ConstantExpr::getGetElementPtr(PointeeTy, C, NewIdxs, inBounds);
}
// If all indices are known integers and normalized, we can do a simple
// check for the "inbounds" property.
if (!Unknown && !inBounds)
if (auto *GV = dyn_cast<GlobalVariable>(C))
if (!GV->hasExternalWeakLinkage() && isInBoundsIndices(Idxs))
return ConstantExpr::getInBoundsGetElementPtr(PointeeTy, C, Idxs);
return nullptr;
}
Constant *llvm::ConstantFoldGetElementPtr(Constant *C,
bool inBounds,
ArrayRef<Constant *> Idxs) {
return ConstantFoldGetElementPtrImpl(
cast<PointerType>(C->getType()->getScalarType())->getElementType(), C,
inBounds, Idxs);
}
Constant *llvm::ConstantFoldGetElementPtr(Constant *C,
bool inBounds,
ArrayRef<Value *> Idxs) {
return ConstantFoldGetElementPtrImpl(
cast<PointerType>(C->getType()->getScalarType())->getElementType(), C,
inBounds, Idxs);
}
Constant *llvm::ConstantFoldGetElementPtr(Type *Ty, Constant *C,
bool inBounds,
ArrayRef<Constant *> Idxs) {
return ConstantFoldGetElementPtrImpl(Ty, C, inBounds, Idxs);
}
Constant *llvm::ConstantFoldGetElementPtr(Type *Ty, Constant *C,
bool inBounds,
ArrayRef<Value *> Idxs) {
return ConstantFoldGetElementPtrImpl(Ty, C, inBounds, Idxs);
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/DiagnosticInfo.cpp | //===- llvm/Support/DiagnosticInfo.cpp - Diagnostic Definitions -*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the different classes involved in low level diagnostics.
//
// Diagnostics reporting is still done as part of the LLVMContext.
//===----------------------------------------------------------------------===//
#include "LLVMContextImpl.h"
#include "llvm/ADT/Twine.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/DiagnosticInfo.h"
#include "llvm/IR/DiagnosticPrinter.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Regex.h"
#include <atomic>
#include <string>
using namespace llvm;
namespace {
/// \brief Regular expression corresponding to the value given in one of the
/// -pass-remarks* command line flags. Passes whose name matches this regexp
/// will emit a diagnostic when calling the associated diagnostic function
/// (emitOptimizationRemark, emitOptimizationRemarkMissed or
/// emitOptimizationRemarkAnalysis).
struct PassRemarksOpt {
std::shared_ptr<Regex> Pattern;
void operator=(const std::string &Val) {
// Create a regexp object to match pass names for emitOptimizationRemark.
if (!Val.empty()) {
Pattern = std::make_shared<Regex>(Val);
std::string RegexError;
if (!Pattern->isValid(RegexError))
report_fatal_error("Invalid regular expression '" + Val +
"' in -pass-remarks: " + RegexError,
false);
}
};
};
#if 0
// These should all be specific to a pipline, not global to the process.
static PassRemarksOpt PassRemarksOptLoc;
static PassRemarksOpt PassRemarksMissedOptLoc;
static PassRemarksOpt PassRemarksAnalysisOptLoc;
// -pass-remarks
// Command line flag to enable emitOptimizationRemark()
static cl::opt<PassRemarksOpt, true, cl::parser<std::string>>
PassRemarks("pass-remarks", cl::value_desc("pattern"),
cl::desc("Enable optimization remarks from passes whose name match "
"the given regular expression"),
cl::Hidden, cl::location(PassRemarksOptLoc), cl::ValueRequired,
cl::ZeroOrMore);
// -pass-remarks-missed
// Command line flag to enable emitOptimizationRemarkMissed()
static cl::opt<PassRemarksOpt, true, cl::parser<std::string>> PassRemarksMissed(
"pass-remarks-missed", cl::value_desc("pattern"),
cl::desc("Enable missed optimization remarks from passes whose name match "
"the given regular expression"),
cl::Hidden, cl::location(PassRemarksMissedOptLoc), cl::ValueRequired,
cl::ZeroOrMore);
// -pass-remarks-analysis
// Command line flag to enable emitOptimizationRemarkAnalysis()
static cl::opt<PassRemarksOpt, true, cl::parser<std::string>>
PassRemarksAnalysis(
"pass-remarks-analysis", cl::value_desc("pattern"),
cl::desc(
"Enable optimization analysis remarks from passes whose name match "
"the given regular expression"),
cl::Hidden, cl::location(PassRemarksAnalysisOptLoc), cl::ValueRequired,
cl::ZeroOrMore);
}
#else
struct PassRemarksOptNull {
Regex *Pattern = nullptr;
void operator=(const std::string &Val) {
}
};
static PassRemarksOptNull PassRemarksOptLoc;
static PassRemarksOptNull PassRemarksMissedOptLoc;
static PassRemarksOptNull PassRemarksAnalysisOptLoc;
// static PassRemarksOptNull PassRemarks; // HLSL Change
// static PassRemarksOptNull PassRemarksMissed; // HLSL Change
// static PassRemarksOptNull PassRemarksAnalysis; // HLSL Change
}
#endif
int llvm::getNextAvailablePluginDiagnosticKind() {
static std::atomic<int> PluginKindID(DK_FirstPluginKind);
return ++PluginKindID;
}
DiagnosticInfoInlineAsm::DiagnosticInfoInlineAsm(const Instruction &I,
const Twine &MsgStr,
DiagnosticSeverity Severity)
: DiagnosticInfo(DK_InlineAsm, Severity), LocCookie(0), MsgStr(MsgStr),
Instr(&I) {
if (const MDNode *SrcLoc = I.getMetadata("srcloc")) {
if (SrcLoc->getNumOperands() != 0)
if (const auto *CI =
mdconst::dyn_extract<ConstantInt>(SrcLoc->getOperand(0)))
LocCookie = CI->getZExtValue();
}
}
void DiagnosticInfoInlineAsm::print(DiagnosticPrinter &DP) const {
DP << getMsgStr();
if (getLocCookie())
DP << " at line " << getLocCookie();
}
void DiagnosticInfoStackSize::print(DiagnosticPrinter &DP) const {
DP << "stack size limit exceeded (" << getStackSize() << ") in "
<< getFunction();
}
void DiagnosticInfoDebugMetadataVersion::print(DiagnosticPrinter &DP) const {
DP << "ignoring debug info with an invalid version (" << getMetadataVersion()
<< ") in " << getModule();
}
void DiagnosticInfoSampleProfile::print(DiagnosticPrinter &DP) const {
if (getFileName() && getLineNum() > 0)
DP << getFileName() << ":" << getLineNum() << ": ";
else if (getFileName())
DP << getFileName() << ": ";
DP << getMsg();
}
bool DiagnosticInfoOptimizationBase::isLocationAvailable() const {
return getDebugLoc();
}
void DiagnosticInfoOptimizationBase::getLocation(StringRef *Filename,
unsigned *Line,
unsigned *Column) const {
DILocation *L = getDebugLoc();
assert(L != nullptr && "debug location is invalid");
*Filename = L->getFilename();
*Line = L->getLine();
*Column = L->getColumn();
}
const std::string DiagnosticInfoOptimizationBase::getLocationStr() const {
StringRef Filename("<unknown>");
unsigned Line = 0;
unsigned Column = 0;
if (isLocationAvailable())
getLocation(&Filename, &Line, &Column);
return (Filename + ":" + Twine(Line) + ":" + Twine(Column)).str();
}
void DiagnosticInfoOptimizationBase::print(DiagnosticPrinter &DP) const {
DP << getLocationStr() << ": " << getMsg();
}
bool DiagnosticInfoOptimizationRemark::isEnabled() const {
return PassRemarksOptLoc.Pattern &&
PassRemarksOptLoc.Pattern->match(getPassName());
}
bool DiagnosticInfoOptimizationRemarkMissed::isEnabled() const {
return PassRemarksMissedOptLoc.Pattern &&
PassRemarksMissedOptLoc.Pattern->match(getPassName());
}
bool DiagnosticInfoOptimizationRemarkAnalysis::isEnabled() const {
return PassRemarksAnalysisOptLoc.Pattern &&
PassRemarksAnalysisOptLoc.Pattern->match(getPassName());
}
void DiagnosticInfoMIRParser::print(DiagnosticPrinter &DP) const {
DP << Diagnostic;
}
void llvm::emitOptimizationRemark(LLVMContext &Ctx, const char *PassName,
const Function &Fn, const DebugLoc &DLoc,
const Twine &Msg) {
Ctx.diagnose(DiagnosticInfoOptimizationRemark(PassName, Fn, DLoc, Msg));
}
void llvm::emitOptimizationRemarkMissed(LLVMContext &Ctx, const char *PassName,
const Function &Fn,
const DebugLoc &DLoc,
const Twine &Msg) {
Ctx.diagnose(DiagnosticInfoOptimizationRemarkMissed(PassName, Fn, DLoc, Msg));
}
void llvm::emitOptimizationRemarkAnalysis(LLVMContext &Ctx,
const char *PassName,
const Function &Fn,
const DebugLoc &DLoc,
const Twine &Msg) {
Ctx.diagnose(
DiagnosticInfoOptimizationRemarkAnalysis(PassName, Fn, DLoc, Msg));
}
bool DiagnosticInfoOptimizationFailure::isEnabled() const {
// Only print warnings.
return getSeverity() == DS_Warning;
}
void llvm::emitLoopVectorizeWarning(LLVMContext &Ctx, const Function &Fn,
const DebugLoc &DLoc, const Twine &Msg) {
Ctx.diagnose(DiagnosticInfoOptimizationFailure(
Fn, DLoc, Twine("loop not vectorized: " + Msg)));
}
void llvm::emitLoopInterleaveWarning(LLVMContext &Ctx, const Function &Fn,
const DebugLoc &DLoc, const Twine &Msg) {
Ctx.diagnose(DiagnosticInfoOptimizationFailure(
Fn, DLoc, Twine("loop not interleaved: " + Msg)));
}
// HLSL Change start - Dxil Diagnostic Info reporter
DiagnosticInfoDxil::DiagnosticInfoDxil(const Function *F, const DILocation *Loc, const Twine &MsgStr,
DiagnosticSeverity Severity)
: DiagnosticInfoDxil(F, MsgStr, Severity)
{
if (Loc) {
HasLocation = true;
FileName = Loc->getFilename();
Line = Loc->getLine();
Column = Loc->getColumn();
}
}
DiagnosticInfoDxil::DiagnosticInfoDxil(const Function *F, const DIGlobalVariable *DGV, const Twine &MsgStr,
DiagnosticSeverity Severity)
: DiagnosticInfoDxil(F, MsgStr, Severity)
{
if (DGV) {
HasLocation = true;
FileName = DGV->getFilename();
Line = DGV->getLine();
Column = 0;
}
}
// Slapdash printing of diagnostic information as a last resort
// Used by validation and linker errors. Doesn't include source snippets.
void DiagnosticInfoDxil::print(DiagnosticPrinter &DP) const {
if (HasLocation) {
DP << FileName << ":" << Line << ":";
if (Column > 0)
DP << Column << ":";
DP << " ";
} else if (Func) {
DP << "Function: " << Func->getName() << ": ";
}
switch (getSeverity()) {
case DiagnosticSeverity::DS_Note: DP << "note: "; break;
case DiagnosticSeverity::DS_Remark: DP << "remark: "; break;
case DiagnosticSeverity::DS_Warning: DP << "warning: "; break;
case DiagnosticSeverity::DS_Error: DP << "error: "; break;
}
DP << getMsgStr();
}
// HLSL Change end - Dxil Diagnostic Info reporter
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/Core.cpp | //===-- Core.cpp ----------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the common infrastructure (including the C bindings)
// for libLLVMCore.a, which implements the LLVM intermediate representation.
//
//===----------------------------------------------------------------------===//
#include "llvm-c/Core.h"
#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/DiagnosticInfo.h"
#include "llvm/IR/DiagnosticPrinter.h"
#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InlineAsm.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/Threading.h"
#include "llvm/Support/raw_ostream.h"
#include <cassert>
#include <cstdlib>
#include <cstring>
#include <system_error>
using namespace llvm;
#define DEBUG_TYPE "ir"
void llvm::initializeCore(PassRegistry &Registry) {
initializeDominatorTreeWrapperPassPass(Registry);
initializePrintModulePassWrapperPass(Registry);
initializePrintFunctionPassWrapperPass(Registry);
initializePrintBasicBlockPassPass(Registry);
initializeVerifierLegacyPassPass(Registry);
}
void LLVMInitializeCore(LLVMPassRegistryRef R) {
initializeCore(*unwrap(R));
}
void LLVMShutdown() {
llvm_shutdown();
}
// HLSL Change: use ISO _strdup rather than strdup, which compiled but fails to link
#ifdef _MSC_VER
#define strdup _strdup
#endif
/*===-- Error handling ----------------------------------------------------===*/
char *LLVMCreateMessage(const char *Message) {
return strdup(Message);
}
void LLVMDisposeMessage(char *Message) {
free(Message);
}
/*===-- Operations on contexts --------------------------------------------===*/
LLVMContextRef LLVMContextCreate() {
return wrap(new LLVMContext());
}
LLVMContextRef LLVMGetGlobalContext() {
return wrap(&getGlobalContext());
}
void LLVMContextSetDiagnosticHandler(LLVMContextRef C,
LLVMDiagnosticHandler Handler,
void *DiagnosticContext) {
unwrap(C)->setDiagnosticHandler(
LLVM_EXTENSION reinterpret_cast<LLVMContext::DiagnosticHandlerTy>(Handler),
DiagnosticContext);
}
void LLVMContextSetYieldCallback(LLVMContextRef C, LLVMYieldCallback Callback,
void *OpaqueHandle) {
auto YieldCallback =
LLVM_EXTENSION reinterpret_cast<LLVMContext::YieldCallbackTy>(Callback);
unwrap(C)->setYieldCallback(YieldCallback, OpaqueHandle);
}
void LLVMContextDispose(LLVMContextRef C) {
delete unwrap(C);
}
unsigned LLVMGetMDKindIDInContext(LLVMContextRef C, const char* Name,
unsigned SLen) {
return unwrap(C)->getMDKindID(StringRef(Name, SLen));
}
unsigned LLVMGetMDKindID(const char* Name, unsigned SLen) {
return LLVMGetMDKindIDInContext(LLVMGetGlobalContext(), Name, SLen);
}
char *LLVMGetDiagInfoDescription(LLVMDiagnosticInfoRef DI) {
std::string MsgStorage;
raw_string_ostream Stream(MsgStorage);
DiagnosticPrinterRawOStream DP(Stream);
unwrap(DI)->print(DP);
Stream.flush();
return LLVMCreateMessage(MsgStorage.c_str());
}
LLVMDiagnosticSeverity LLVMGetDiagInfoSeverity(LLVMDiagnosticInfoRef DI){
LLVMDiagnosticSeverity severity;
switch(unwrap(DI)->getSeverity()) {
default:
severity = LLVMDSError;
break;
case DS_Warning:
severity = LLVMDSWarning;
break;
case DS_Remark:
severity = LLVMDSRemark;
break;
case DS_Note:
severity = LLVMDSNote;
break;
}
return severity;
}
/*===-- Operations on modules ---------------------------------------------===*/
LLVMModuleRef LLVMModuleCreateWithName(const char *ModuleID) {
return wrap(new Module(ModuleID, getGlobalContext()));
}
LLVMModuleRef LLVMModuleCreateWithNameInContext(const char *ModuleID,
LLVMContextRef C) {
return wrap(new Module(ModuleID, *unwrap(C)));
}
void LLVMDisposeModule(LLVMModuleRef M) {
delete unwrap(M);
}
/*--.. Data layout .........................................................--*/
const char * LLVMGetDataLayout(LLVMModuleRef M) {
return unwrap(M)->getDataLayoutStr().c_str();
}
void LLVMSetDataLayout(LLVMModuleRef M, const char *Triple) {
unwrap(M)->setDataLayout(Triple);
}
/*--.. Target triple .......................................................--*/
const char * LLVMGetTarget(LLVMModuleRef M) {
return unwrap(M)->getTargetTriple().c_str();
}
void LLVMSetTarget(LLVMModuleRef M, const char *Triple) {
unwrap(M)->setTargetTriple(Triple);
}
void LLVMDumpModule(LLVMModuleRef M) {
unwrap(M)->dump();
}
LLVMBool LLVMPrintModuleToFile(LLVMModuleRef M, const char *Filename,
char **ErrorMessage) {
std::error_code EC;
raw_fd_ostream dest(Filename, EC, sys::fs::F_Text);
if (EC) {
*ErrorMessage = strdup(EC.message().c_str());
return true;
}
unwrap(M)->print(dest, nullptr);
dest.close();
if (dest.has_error()) {
*ErrorMessage = strdup("Error printing to file");
return true;
}
return false;
}
char *LLVMPrintModuleToString(LLVMModuleRef M) {
std::string buf;
raw_string_ostream os(buf);
unwrap(M)->print(os, nullptr);
os.flush();
return strdup(buf.c_str());
}
/*--.. Operations on inline assembler ......................................--*/
void LLVMSetModuleInlineAsm(LLVMModuleRef M, const char *Asm) {
unwrap(M)->setModuleInlineAsm(StringRef(Asm));
}
/*--.. Operations on module contexts ......................................--*/
LLVMContextRef LLVMGetModuleContext(LLVMModuleRef M) {
return wrap(&unwrap(M)->getContext());
}
/*===-- Operations on types -----------------------------------------------===*/
/*--.. Operations on all types (mostly) ....................................--*/
LLVMTypeKind LLVMGetTypeKind(LLVMTypeRef Ty) {
switch (unwrap(Ty)->getTypeID()) {
case Type::VoidTyID:
return LLVMVoidTypeKind;
case Type::HalfTyID:
return LLVMHalfTypeKind;
case Type::FloatTyID:
return LLVMFloatTypeKind;
case Type::DoubleTyID:
return LLVMDoubleTypeKind;
case Type::X86_FP80TyID:
return LLVMX86_FP80TypeKind;
case Type::FP128TyID:
return LLVMFP128TypeKind;
case Type::PPC_FP128TyID:
return LLVMPPC_FP128TypeKind;
case Type::LabelTyID:
return LLVMLabelTypeKind;
case Type::MetadataTyID:
return LLVMMetadataTypeKind;
case Type::IntegerTyID:
return LLVMIntegerTypeKind;
case Type::FunctionTyID:
return LLVMFunctionTypeKind;
case Type::StructTyID:
return LLVMStructTypeKind;
case Type::ArrayTyID:
return LLVMArrayTypeKind;
case Type::PointerTyID:
return LLVMPointerTypeKind;
case Type::VectorTyID:
return LLVMVectorTypeKind;
case Type::X86_MMXTyID:
return LLVMX86_MMXTypeKind;
}
llvm_unreachable("Unhandled TypeID.");
}
LLVMBool LLVMTypeIsSized(LLVMTypeRef Ty)
{
return unwrap(Ty)->isSized();
}
LLVMContextRef LLVMGetTypeContext(LLVMTypeRef Ty) {
return wrap(&unwrap(Ty)->getContext());
}
void LLVMDumpType(LLVMTypeRef Ty) {
return unwrap(Ty)->dump();
}
char *LLVMPrintTypeToString(LLVMTypeRef Ty) {
std::string buf;
raw_string_ostream os(buf);
if (unwrap(Ty))
unwrap(Ty)->print(os);
else
os << "Printing <null> Type";
os.flush();
return strdup(buf.c_str());
}
/*--.. Operations on integer types .........................................--*/
LLVMTypeRef LLVMInt1TypeInContext(LLVMContextRef C) {
return (LLVMTypeRef) Type::getInt1Ty(*unwrap(C));
}
LLVMTypeRef LLVMInt8TypeInContext(LLVMContextRef C) {
return (LLVMTypeRef) Type::getInt8Ty(*unwrap(C));
}
LLVMTypeRef LLVMInt16TypeInContext(LLVMContextRef C) {
return (LLVMTypeRef) Type::getInt16Ty(*unwrap(C));
}
LLVMTypeRef LLVMInt32TypeInContext(LLVMContextRef C) {
return (LLVMTypeRef) Type::getInt32Ty(*unwrap(C));
}
LLVMTypeRef LLVMInt64TypeInContext(LLVMContextRef C) {
return (LLVMTypeRef) Type::getInt64Ty(*unwrap(C));
}
LLVMTypeRef LLVMInt128TypeInContext(LLVMContextRef C) {
return (LLVMTypeRef) Type::getInt128Ty(*unwrap(C));
}
LLVMTypeRef LLVMIntTypeInContext(LLVMContextRef C, unsigned NumBits) {
return wrap(IntegerType::get(*unwrap(C), NumBits));
}
LLVMTypeRef LLVMInt1Type(void) {
return LLVMInt1TypeInContext(LLVMGetGlobalContext());
}
LLVMTypeRef LLVMInt8Type(void) {
return LLVMInt8TypeInContext(LLVMGetGlobalContext());
}
LLVMTypeRef LLVMInt16Type(void) {
return LLVMInt16TypeInContext(LLVMGetGlobalContext());
}
LLVMTypeRef LLVMInt32Type(void) {
return LLVMInt32TypeInContext(LLVMGetGlobalContext());
}
LLVMTypeRef LLVMInt64Type(void) {
return LLVMInt64TypeInContext(LLVMGetGlobalContext());
}
LLVMTypeRef LLVMInt128Type(void) {
return LLVMInt128TypeInContext(LLVMGetGlobalContext());
}
LLVMTypeRef LLVMIntType(unsigned NumBits) {
return LLVMIntTypeInContext(LLVMGetGlobalContext(), NumBits);
}
unsigned LLVMGetIntTypeWidth(LLVMTypeRef IntegerTy) {
return unwrap<IntegerType>(IntegerTy)->getBitWidth();
}
/*--.. Operations on real types ............................................--*/
LLVMTypeRef LLVMHalfTypeInContext(LLVMContextRef C) {
return (LLVMTypeRef) Type::getHalfTy(*unwrap(C));
}
LLVMTypeRef LLVMFloatTypeInContext(LLVMContextRef C) {
return (LLVMTypeRef) Type::getFloatTy(*unwrap(C));
}
LLVMTypeRef LLVMDoubleTypeInContext(LLVMContextRef C) {
return (LLVMTypeRef) Type::getDoubleTy(*unwrap(C));
}
LLVMTypeRef LLVMX86FP80TypeInContext(LLVMContextRef C) {
return (LLVMTypeRef) Type::getX86_FP80Ty(*unwrap(C));
}
LLVMTypeRef LLVMFP128TypeInContext(LLVMContextRef C) {
return (LLVMTypeRef) Type::getFP128Ty(*unwrap(C));
}
LLVMTypeRef LLVMPPCFP128TypeInContext(LLVMContextRef C) {
return (LLVMTypeRef) Type::getPPC_FP128Ty(*unwrap(C));
}
LLVMTypeRef LLVMX86MMXTypeInContext(LLVMContextRef C) {
return (LLVMTypeRef) Type::getX86_MMXTy(*unwrap(C));
}
LLVMTypeRef LLVMHalfType(void) {
return LLVMHalfTypeInContext(LLVMGetGlobalContext());
}
LLVMTypeRef LLVMFloatType(void) {
return LLVMFloatTypeInContext(LLVMGetGlobalContext());
}
LLVMTypeRef LLVMDoubleType(void) {
return LLVMDoubleTypeInContext(LLVMGetGlobalContext());
}
LLVMTypeRef LLVMX86FP80Type(void) {
return LLVMX86FP80TypeInContext(LLVMGetGlobalContext());
}
LLVMTypeRef LLVMFP128Type(void) {
return LLVMFP128TypeInContext(LLVMGetGlobalContext());
}
LLVMTypeRef LLVMPPCFP128Type(void) {
return LLVMPPCFP128TypeInContext(LLVMGetGlobalContext());
}
LLVMTypeRef LLVMX86MMXType(void) {
return LLVMX86MMXTypeInContext(LLVMGetGlobalContext());
}
/*--.. Operations on function types ........................................--*/
LLVMTypeRef LLVMFunctionType(LLVMTypeRef ReturnType,
LLVMTypeRef *ParamTypes, unsigned ParamCount,
LLVMBool IsVarArg) {
ArrayRef<Type*> Tys(unwrap(ParamTypes), ParamCount);
return wrap(FunctionType::get(unwrap(ReturnType), Tys, IsVarArg != 0));
}
LLVMBool LLVMIsFunctionVarArg(LLVMTypeRef FunctionTy) {
return unwrap<FunctionType>(FunctionTy)->isVarArg();
}
LLVMTypeRef LLVMGetReturnType(LLVMTypeRef FunctionTy) {
return wrap(unwrap<FunctionType>(FunctionTy)->getReturnType());
}
unsigned LLVMCountParamTypes(LLVMTypeRef FunctionTy) {
return unwrap<FunctionType>(FunctionTy)->getNumParams();
}
void LLVMGetParamTypes(LLVMTypeRef FunctionTy, LLVMTypeRef *Dest) {
FunctionType *Ty = unwrap<FunctionType>(FunctionTy);
for (FunctionType::param_iterator I = Ty->param_begin(),
E = Ty->param_end(); I != E; ++I)
*Dest++ = wrap(*I);
}
/*--.. Operations on struct types ..........................................--*/
LLVMTypeRef LLVMStructTypeInContext(LLVMContextRef C, LLVMTypeRef *ElementTypes,
unsigned ElementCount, LLVMBool Packed) {
ArrayRef<Type*> Tys(unwrap(ElementTypes), ElementCount);
return wrap(StructType::get(*unwrap(C), Tys, Packed != 0));
}
LLVMTypeRef LLVMStructType(LLVMTypeRef *ElementTypes,
unsigned ElementCount, LLVMBool Packed) {
return LLVMStructTypeInContext(LLVMGetGlobalContext(), ElementTypes,
ElementCount, Packed);
}
LLVMTypeRef LLVMStructCreateNamed(LLVMContextRef C, const char *Name)
{
return wrap(StructType::create(*unwrap(C), Name));
}
const char *LLVMGetStructName(LLVMTypeRef Ty)
{
StructType *Type = unwrap<StructType>(Ty);
if (!Type->hasName())
return nullptr;
return Type->getName().data();
}
void LLVMStructSetBody(LLVMTypeRef StructTy, LLVMTypeRef *ElementTypes,
unsigned ElementCount, LLVMBool Packed) {
ArrayRef<Type*> Tys(unwrap(ElementTypes), ElementCount);
unwrap<StructType>(StructTy)->setBody(Tys, Packed != 0);
}
unsigned LLVMCountStructElementTypes(LLVMTypeRef StructTy) {
return unwrap<StructType>(StructTy)->getNumElements();
}
void LLVMGetStructElementTypes(LLVMTypeRef StructTy, LLVMTypeRef *Dest) {
StructType *Ty = unwrap<StructType>(StructTy);
for (StructType::element_iterator I = Ty->element_begin(),
E = Ty->element_end(); I != E; ++I)
*Dest++ = wrap(*I);
}
LLVMTypeRef LLVMStructGetTypeAtIndex(LLVMTypeRef StructTy, unsigned i) {
StructType *Ty = unwrap<StructType>(StructTy);
return wrap(Ty->getTypeAtIndex(i));
}
LLVMBool LLVMIsPackedStruct(LLVMTypeRef StructTy) {
return unwrap<StructType>(StructTy)->isPacked();
}
LLVMBool LLVMIsOpaqueStruct(LLVMTypeRef StructTy) {
return unwrap<StructType>(StructTy)->isOpaque();
}
LLVMTypeRef LLVMGetTypeByName(LLVMModuleRef M, const char *Name) {
return wrap(unwrap(M)->getTypeByName(Name));
}
/*--.. Operations on array, pointer, and vector types (sequence types) .....--*/
LLVMTypeRef LLVMArrayType(LLVMTypeRef ElementType, unsigned ElementCount) {
return wrap(ArrayType::get(unwrap(ElementType), ElementCount));
}
LLVMTypeRef LLVMPointerType(LLVMTypeRef ElementType, unsigned AddressSpace) {
return wrap(PointerType::get(unwrap(ElementType), AddressSpace));
}
LLVMTypeRef LLVMVectorType(LLVMTypeRef ElementType, unsigned ElementCount) {
return wrap(VectorType::get(unwrap(ElementType), ElementCount));
}
LLVMTypeRef LLVMGetElementType(LLVMTypeRef Ty) {
return wrap(unwrap<SequentialType>(Ty)->getElementType());
}
unsigned LLVMGetArrayLength(LLVMTypeRef ArrayTy) {
return unwrap<ArrayType>(ArrayTy)->getNumElements();
}
unsigned LLVMGetPointerAddressSpace(LLVMTypeRef PointerTy) {
return unwrap<PointerType>(PointerTy)->getAddressSpace();
}
unsigned LLVMGetVectorSize(LLVMTypeRef VectorTy) {
return unwrap<VectorType>(VectorTy)->getNumElements();
}
/*--.. Operations on other types ...........................................--*/
LLVMTypeRef LLVMVoidTypeInContext(LLVMContextRef C) {
return wrap(Type::getVoidTy(*unwrap(C)));
}
LLVMTypeRef LLVMLabelTypeInContext(LLVMContextRef C) {
return wrap(Type::getLabelTy(*unwrap(C)));
}
LLVMTypeRef LLVMVoidType(void) {
return LLVMVoidTypeInContext(LLVMGetGlobalContext());
}
LLVMTypeRef LLVMLabelType(void) {
return LLVMLabelTypeInContext(LLVMGetGlobalContext());
}
/*===-- Operations on values ----------------------------------------------===*/
/*--.. Operations on all values ............................................--*/
LLVMTypeRef LLVMTypeOf(LLVMValueRef Val) {
return wrap(unwrap(Val)->getType());
}
const char *LLVMGetValueName(LLVMValueRef Val) {
return unwrap(Val)->getName().data();
}
void LLVMSetValueName(LLVMValueRef Val, const char *Name) {
unwrap(Val)->setName(Name);
}
void LLVMDumpValue(LLVMValueRef Val) {
unwrap(Val)->dump();
}
char* LLVMPrintValueToString(LLVMValueRef Val) {
std::string buf;
raw_string_ostream os(buf);
if (unwrap(Val))
unwrap(Val)->print(os);
else
os << "Printing <null> Value";
os.flush();
return strdup(buf.c_str());
}
void LLVMReplaceAllUsesWith(LLVMValueRef OldVal, LLVMValueRef NewVal) {
unwrap(OldVal)->replaceAllUsesWith(unwrap(NewVal));
}
int LLVMHasMetadata(LLVMValueRef Inst) {
return unwrap<Instruction>(Inst)->hasMetadata();
}
LLVMValueRef LLVMGetMetadata(LLVMValueRef Inst, unsigned KindID) {
auto *I = unwrap<Instruction>(Inst);
assert(I && "Expected instruction");
if (auto *MD = I->getMetadata(KindID))
return wrap(MetadataAsValue::get(I->getContext(), MD));
return nullptr;
}
// MetadataAsValue uses a canonical format which strips the actual MDNode for
// MDNode with just a single constant value, storing just a ConstantAsMetadata
// This undoes this canonicalization, reconstructing the MDNode.
static MDNode *extractMDNode(MetadataAsValue *MAV) {
Metadata *MD = MAV->getMetadata();
assert((isa<MDNode>(MD) || isa<ConstantAsMetadata>(MD)) &&
"Expected a metadata node or a canonicalized constant");
if (MDNode *N = dyn_cast<MDNode>(MD))
return N;
return MDNode::get(MAV->getContext(), MD);
}
void LLVMSetMetadata(LLVMValueRef Inst, unsigned KindID, LLVMValueRef Val) {
MDNode *N = Val ? extractMDNode(unwrap<MetadataAsValue>(Val)) : nullptr;
unwrap<Instruction>(Inst)->setMetadata(KindID, N);
}
/*--.. Conversion functions ................................................--*/
#define LLVM_DEFINE_VALUE_CAST(name) \
LLVMValueRef LLVMIsA##name(LLVMValueRef Val) { \
return wrap(static_cast<Value*>(dyn_cast_or_null<name>(unwrap(Val)))); \
}
LLVM_FOR_EACH_VALUE_SUBCLASS(LLVM_DEFINE_VALUE_CAST)
LLVMValueRef LLVMIsAMDNode(LLVMValueRef Val) {
if (auto *MD = dyn_cast_or_null<MetadataAsValue>(unwrap(Val)))
if (isa<MDNode>(MD->getMetadata()) ||
isa<ValueAsMetadata>(MD->getMetadata()))
return Val;
return nullptr;
}
LLVMValueRef LLVMIsAMDString(LLVMValueRef Val) {
if (auto *MD = dyn_cast_or_null<MetadataAsValue>(unwrap(Val)))
if (isa<MDString>(MD->getMetadata()))
return Val;
return nullptr;
}
/*--.. Operations on Uses ..................................................--*/
LLVMUseRef LLVMGetFirstUse(LLVMValueRef Val) {
Value *V = unwrap(Val);
Value::use_iterator I = V->use_begin();
if (I == V->use_end())
return nullptr;
return wrap(&*I);
}
LLVMUseRef LLVMGetNextUse(LLVMUseRef U) {
Use *Next = unwrap(U)->getNext();
if (Next)
return wrap(Next);
return nullptr;
}
LLVMValueRef LLVMGetUser(LLVMUseRef U) {
return wrap(unwrap(U)->getUser());
}
LLVMValueRef LLVMGetUsedValue(LLVMUseRef U) {
return wrap(unwrap(U)->get());
}
/*--.. Operations on Users .................................................--*/
static LLVMValueRef getMDNodeOperandImpl(LLVMContext &Context, const MDNode *N,
unsigned Index) {
Metadata *Op = N->getOperand(Index);
if (!Op)
return nullptr;
if (auto *C = dyn_cast<ConstantAsMetadata>(Op))
return wrap(C->getValue());
return wrap(MetadataAsValue::get(Context, Op));
}
LLVMValueRef LLVMGetOperand(LLVMValueRef Val, unsigned Index) {
Value *V = unwrap(Val);
if (auto *MD = dyn_cast<MetadataAsValue>(V)) {
if (auto *L = dyn_cast<ValueAsMetadata>(MD->getMetadata())) {
assert(Index == 0 && "Function-local metadata can only have one operand");
return wrap(L->getValue());
}
return getMDNodeOperandImpl(V->getContext(),
cast<MDNode>(MD->getMetadata()), Index);
}
return wrap(cast<User>(V)->getOperand(Index));
}
LLVMUseRef LLVMGetOperandUse(LLVMValueRef Val, unsigned Index) {
Value *V = unwrap(Val);
return wrap(&cast<User>(V)->getOperandUse(Index));
}
void LLVMSetOperand(LLVMValueRef Val, unsigned Index, LLVMValueRef Op) {
unwrap<User>(Val)->setOperand(Index, unwrap(Op));
}
int LLVMGetNumOperands(LLVMValueRef Val) {
Value *V = unwrap(Val);
if (isa<MetadataAsValue>(V))
return LLVMGetMDNodeNumOperands(Val);
return cast<User>(V)->getNumOperands();
}
/*--.. Operations on constants of any type .................................--*/
LLVMValueRef LLVMConstNull(LLVMTypeRef Ty) {
return wrap(Constant::getNullValue(unwrap(Ty)));
}
LLVMValueRef LLVMConstAllOnes(LLVMTypeRef Ty) {
return wrap(Constant::getAllOnesValue(unwrap(Ty)));
}
LLVMValueRef LLVMGetUndef(LLVMTypeRef Ty) {
return wrap(UndefValue::get(unwrap(Ty)));
}
LLVMBool LLVMIsConstant(LLVMValueRef Ty) {
return isa<Constant>(unwrap(Ty));
}
LLVMBool LLVMIsNull(LLVMValueRef Val) {
if (Constant *C = dyn_cast<Constant>(unwrap(Val)))
return C->isNullValue();
return false;
}
LLVMBool LLVMIsUndef(LLVMValueRef Val) {
return isa<UndefValue>(unwrap(Val));
}
LLVMValueRef LLVMConstPointerNull(LLVMTypeRef Ty) {
return
wrap(ConstantPointerNull::get(unwrap<PointerType>(Ty)));
}
/*--.. Operations on metadata nodes ........................................--*/
LLVMValueRef LLVMMDStringInContext(LLVMContextRef C, const char *Str,
unsigned SLen) {
LLVMContext &Context = *unwrap(C);
return wrap(MetadataAsValue::get(
Context, MDString::get(Context, StringRef(Str, SLen))));
}
LLVMValueRef LLVMMDString(const char *Str, unsigned SLen) {
return LLVMMDStringInContext(LLVMGetGlobalContext(), Str, SLen);
}
LLVMValueRef LLVMMDNodeInContext(LLVMContextRef C, LLVMValueRef *Vals,
unsigned Count) {
LLVMContext &Context = *unwrap(C);
SmallVector<Metadata *, 8> MDs;
for (auto *OV : makeArrayRef(Vals, Count)) {
Value *V = unwrap(OV);
Metadata *MD;
if (!V)
MD = nullptr;
else if (auto *C = dyn_cast<Constant>(V))
MD = ConstantAsMetadata::get(C);
else if (auto *MDV = dyn_cast<MetadataAsValue>(V)) {
MD = MDV->getMetadata();
assert(!isa<LocalAsMetadata>(MD) && "Unexpected function-local metadata "
"outside of direct argument to call");
} else {
// This is function-local metadata. Pretend to make an MDNode.
assert(Count == 1 &&
"Expected only one operand to function-local metadata");
return wrap(MetadataAsValue::get(Context, LocalAsMetadata::get(V)));
}
MDs.push_back(MD);
}
return wrap(MetadataAsValue::get(Context, MDNode::get(Context, MDs)));
}
LLVMValueRef LLVMMDNode(LLVMValueRef *Vals, unsigned Count) {
return LLVMMDNodeInContext(LLVMGetGlobalContext(), Vals, Count);
}
const char *LLVMGetMDString(LLVMValueRef V, unsigned* Len) {
if (const auto *MD = dyn_cast<MetadataAsValue>(unwrap(V)))
if (const MDString *S = dyn_cast<MDString>(MD->getMetadata())) {
*Len = S->getString().size();
return S->getString().data();
}
*Len = 0;
return nullptr;
}
unsigned LLVMGetMDNodeNumOperands(LLVMValueRef V)
{
auto *MD = cast<MetadataAsValue>(unwrap(V));
if (isa<ValueAsMetadata>(MD->getMetadata()))
return 1;
return cast<MDNode>(MD->getMetadata())->getNumOperands();
}
void LLVMGetMDNodeOperands(LLVMValueRef V, LLVMValueRef *Dest)
{
auto *MD = cast<MetadataAsValue>(unwrap(V));
if (auto *MDV = dyn_cast<ValueAsMetadata>(MD->getMetadata())) {
*Dest = wrap(MDV->getValue());
return;
}
const auto *N = cast<MDNode>(MD->getMetadata());
const unsigned numOperands = N->getNumOperands();
LLVMContext &Context = unwrap(V)->getContext();
for (unsigned i = 0; i < numOperands; i++)
Dest[i] = getMDNodeOperandImpl(Context, N, i);
}
unsigned LLVMGetNamedMetadataNumOperands(LLVMModuleRef M, const char* name)
{
if (NamedMDNode *N = unwrap(M)->getNamedMetadata(name)) {
return N->getNumOperands();
}
return 0;
}
void LLVMGetNamedMetadataOperands(LLVMModuleRef M, const char* name, LLVMValueRef *Dest)
{
NamedMDNode *N = unwrap(M)->getNamedMetadata(name);
if (!N)
return;
LLVMContext &Context = unwrap(M)->getContext();
for (unsigned i=0;i<N->getNumOperands();i++)
Dest[i] = wrap(MetadataAsValue::get(Context, N->getOperand(i)));
}
void LLVMAddNamedMetadataOperand(LLVMModuleRef M, const char* name,
LLVMValueRef Val)
{
NamedMDNode *N = unwrap(M)->getOrInsertNamedMetadata(name);
if (!N)
return;
if (!Val)
return;
N->addOperand(extractMDNode(unwrap<MetadataAsValue>(Val)));
}
/*--.. Operations on scalar constants ......................................--*/
LLVMValueRef LLVMConstInt(LLVMTypeRef IntTy, unsigned long long N,
LLVMBool SignExtend) {
return wrap(ConstantInt::get(unwrap<IntegerType>(IntTy), N, SignExtend != 0));
}
LLVMValueRef LLVMConstIntOfArbitraryPrecision(LLVMTypeRef IntTy,
unsigned NumWords,
const uint64_t Words[]) {
IntegerType *Ty = unwrap<IntegerType>(IntTy);
return wrap(ConstantInt::get(Ty->getContext(),
APInt(Ty->getBitWidth(),
makeArrayRef(Words, NumWords))));
}
LLVMValueRef LLVMConstIntOfString(LLVMTypeRef IntTy, const char Str[],
uint8_t Radix) {
return wrap(ConstantInt::get(unwrap<IntegerType>(IntTy), StringRef(Str),
Radix));
}
LLVMValueRef LLVMConstIntOfStringAndSize(LLVMTypeRef IntTy, const char Str[],
unsigned SLen, uint8_t Radix) {
return wrap(ConstantInt::get(unwrap<IntegerType>(IntTy), StringRef(Str, SLen),
Radix));
}
LLVMValueRef LLVMConstReal(LLVMTypeRef RealTy, double N) {
return wrap(ConstantFP::get(unwrap(RealTy), N));
}
LLVMValueRef LLVMConstRealOfString(LLVMTypeRef RealTy, const char *Text) {
return wrap(ConstantFP::get(unwrap(RealTy), StringRef(Text)));
}
LLVMValueRef LLVMConstRealOfStringAndSize(LLVMTypeRef RealTy, const char Str[],
unsigned SLen) {
return wrap(ConstantFP::get(unwrap(RealTy), StringRef(Str, SLen)));
}
unsigned long long LLVMConstIntGetZExtValue(LLVMValueRef ConstantVal) {
return unwrap<ConstantInt>(ConstantVal)->getZExtValue();
}
long long LLVMConstIntGetSExtValue(LLVMValueRef ConstantVal) {
return unwrap<ConstantInt>(ConstantVal)->getSExtValue();
}
double LLVMConstRealGetDouble(LLVMValueRef ConstantVal, LLVMBool *LosesInfo) {
ConstantFP *cFP = unwrap<ConstantFP>(ConstantVal) ;
Type *Ty = cFP->getType();
if (Ty->isFloatTy()) {
*LosesInfo = false;
return cFP->getValueAPF().convertToFloat();
}
if (Ty->isDoubleTy()) {
*LosesInfo = false;
return cFP->getValueAPF().convertToDouble();
}
bool APFLosesInfo;
APFloat APF = cFP->getValueAPF();
APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven, &APFLosesInfo);
*LosesInfo = APFLosesInfo;
return APF.convertToDouble();
}
/*--.. Operations on composite constants ...................................--*/
LLVMValueRef LLVMConstStringInContext(LLVMContextRef C, const char *Str,
unsigned Length,
LLVMBool DontNullTerminate) {
/* Inverted the sense of AddNull because ', 0)' is a
better mnemonic for null termination than ', 1)'. */
return wrap(ConstantDataArray::getString(*unwrap(C), StringRef(Str, Length),
DontNullTerminate == 0));
}
LLVMValueRef LLVMConstStructInContext(LLVMContextRef C,
LLVMValueRef *ConstantVals,
unsigned Count, LLVMBool Packed) {
Constant **Elements = unwrap<Constant>(ConstantVals, Count);
return wrap(ConstantStruct::getAnon(*unwrap(C), makeArrayRef(Elements, Count),
Packed != 0));
}
LLVMValueRef LLVMConstString(const char *Str, unsigned Length,
LLVMBool DontNullTerminate) {
return LLVMConstStringInContext(LLVMGetGlobalContext(), Str, Length,
DontNullTerminate);
}
LLVMValueRef LLVMGetElementAsConstant(LLVMValueRef c, unsigned idx) {
return wrap(static_cast<ConstantDataSequential*>(unwrap(c))->getElementAsConstant(idx));
}
LLVMBool LLVMIsConstantString(LLVMValueRef c) {
return static_cast<ConstantDataSequential*>(unwrap(c))->isString();
}
const char *LLVMGetAsString(LLVMValueRef c, size_t* Length) {
StringRef str = static_cast<ConstantDataSequential*>(unwrap(c))->getAsString();
*Length = str.size();
return str.data();
}
LLVMValueRef LLVMConstArray(LLVMTypeRef ElementTy,
LLVMValueRef *ConstantVals, unsigned Length) {
ArrayRef<Constant*> V(unwrap<Constant>(ConstantVals, Length), Length);
return wrap(ConstantArray::get(ArrayType::get(unwrap(ElementTy), Length), V));
}
LLVMValueRef LLVMConstStruct(LLVMValueRef *ConstantVals, unsigned Count,
LLVMBool Packed) {
return LLVMConstStructInContext(LLVMGetGlobalContext(), ConstantVals, Count,
Packed);
}
LLVMValueRef LLVMConstNamedStruct(LLVMTypeRef StructTy,
LLVMValueRef *ConstantVals,
unsigned Count) {
Constant **Elements = unwrap<Constant>(ConstantVals, Count);
StructType *Ty = cast<StructType>(unwrap(StructTy));
return wrap(ConstantStruct::get(Ty, makeArrayRef(Elements, Count)));
}
LLVMValueRef LLVMConstVector(LLVMValueRef *ScalarConstantVals, unsigned Size) {
return wrap(ConstantVector::get(makeArrayRef(
unwrap<Constant>(ScalarConstantVals, Size), Size)));
}
/*-- Opcode mapping */
static LLVMOpcode map_to_llvmopcode(int opcode)
{
switch (opcode) {
default: llvm_unreachable("Unhandled Opcode.");
#define HANDLE_INST(num, opc, clas) case num: return LLVM##opc;
#include "llvm/IR/Instruction.def"
#undef HANDLE_INST
}
}
static int map_from_llvmopcode(LLVMOpcode code)
{
switch (code) {
#define HANDLE_INST(num, opc, clas) case LLVM##opc: return num;
#include "llvm/IR/Instruction.def"
#undef HANDLE_INST
}
llvm_unreachable("Unhandled Opcode.");
}
/*--.. Constant expressions ................................................--*/
LLVMOpcode LLVMGetConstOpcode(LLVMValueRef ConstantVal) {
return map_to_llvmopcode(unwrap<ConstantExpr>(ConstantVal)->getOpcode());
}
LLVMValueRef LLVMAlignOf(LLVMTypeRef Ty) {
return wrap(ConstantExpr::getAlignOf(unwrap(Ty)));
}
LLVMValueRef LLVMSizeOf(LLVMTypeRef Ty) {
return wrap(ConstantExpr::getSizeOf(unwrap(Ty)));
}
LLVMValueRef LLVMConstNeg(LLVMValueRef ConstantVal) {
return wrap(ConstantExpr::getNeg(unwrap<Constant>(ConstantVal)));
}
LLVMValueRef LLVMConstNSWNeg(LLVMValueRef ConstantVal) {
return wrap(ConstantExpr::getNSWNeg(unwrap<Constant>(ConstantVal)));
}
LLVMValueRef LLVMConstNUWNeg(LLVMValueRef ConstantVal) {
return wrap(ConstantExpr::getNUWNeg(unwrap<Constant>(ConstantVal)));
}
LLVMValueRef LLVMConstFNeg(LLVMValueRef ConstantVal) {
return wrap(ConstantExpr::getFNeg(unwrap<Constant>(ConstantVal)));
}
LLVMValueRef LLVMConstNot(LLVMValueRef ConstantVal) {
return wrap(ConstantExpr::getNot(unwrap<Constant>(ConstantVal)));
}
LLVMValueRef LLVMConstAdd(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getAdd(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstNSWAdd(LLVMValueRef LHSConstant,
LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getNSWAdd(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstNUWAdd(LLVMValueRef LHSConstant,
LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getNUWAdd(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstFAdd(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getFAdd(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstSub(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getSub(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstNSWSub(LLVMValueRef LHSConstant,
LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getNSWSub(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstNUWSub(LLVMValueRef LHSConstant,
LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getNUWSub(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstFSub(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getFSub(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstMul(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getMul(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstNSWMul(LLVMValueRef LHSConstant,
LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getNSWMul(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstNUWMul(LLVMValueRef LHSConstant,
LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getNUWMul(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstFMul(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getFMul(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstUDiv(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getUDiv(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstSDiv(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getSDiv(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstExactSDiv(LLVMValueRef LHSConstant,
LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getExactSDiv(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstFDiv(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getFDiv(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstURem(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getURem(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstSRem(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getSRem(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstFRem(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getFRem(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstAnd(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getAnd(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstOr(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getOr(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstXor(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getXor(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstICmp(LLVMIntPredicate Predicate,
LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getICmp(Predicate,
unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstFCmp(LLVMRealPredicate Predicate,
LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getFCmp(Predicate,
unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstShl(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getShl(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstLShr(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getLShr(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstAShr(LLVMValueRef LHSConstant, LLVMValueRef RHSConstant) {
return wrap(ConstantExpr::getAShr(unwrap<Constant>(LHSConstant),
unwrap<Constant>(RHSConstant)));
}
LLVMValueRef LLVMConstGEP(LLVMValueRef ConstantVal,
LLVMValueRef *ConstantIndices, unsigned NumIndices) {
ArrayRef<Constant *> IdxList(unwrap<Constant>(ConstantIndices, NumIndices),
NumIndices);
return wrap(ConstantExpr::getGetElementPtr(
nullptr, unwrap<Constant>(ConstantVal), IdxList));
}
LLVMValueRef LLVMConstInBoundsGEP(LLVMValueRef ConstantVal,
LLVMValueRef *ConstantIndices,
unsigned NumIndices) {
Constant* Val = unwrap<Constant>(ConstantVal);
ArrayRef<Constant *> IdxList(unwrap<Constant>(ConstantIndices, NumIndices),
NumIndices);
return wrap(ConstantExpr::getInBoundsGetElementPtr(nullptr, Val, IdxList));
}
LLVMValueRef LLVMConstTrunc(LLVMValueRef ConstantVal, LLVMTypeRef ToType) {
return wrap(ConstantExpr::getTrunc(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstSExt(LLVMValueRef ConstantVal, LLVMTypeRef ToType) {
return wrap(ConstantExpr::getSExt(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstZExt(LLVMValueRef ConstantVal, LLVMTypeRef ToType) {
return wrap(ConstantExpr::getZExt(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstFPTrunc(LLVMValueRef ConstantVal, LLVMTypeRef ToType) {
return wrap(ConstantExpr::getFPTrunc(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstFPExt(LLVMValueRef ConstantVal, LLVMTypeRef ToType) {
return wrap(ConstantExpr::getFPExtend(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstUIToFP(LLVMValueRef ConstantVal, LLVMTypeRef ToType) {
return wrap(ConstantExpr::getUIToFP(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstSIToFP(LLVMValueRef ConstantVal, LLVMTypeRef ToType) {
return wrap(ConstantExpr::getSIToFP(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstFPToUI(LLVMValueRef ConstantVal, LLVMTypeRef ToType) {
return wrap(ConstantExpr::getFPToUI(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstFPToSI(LLVMValueRef ConstantVal, LLVMTypeRef ToType) {
return wrap(ConstantExpr::getFPToSI(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstPtrToInt(LLVMValueRef ConstantVal, LLVMTypeRef ToType) {
return wrap(ConstantExpr::getPtrToInt(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstIntToPtr(LLVMValueRef ConstantVal, LLVMTypeRef ToType) {
return wrap(ConstantExpr::getIntToPtr(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstBitCast(LLVMValueRef ConstantVal, LLVMTypeRef ToType) {
return wrap(ConstantExpr::getBitCast(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstAddrSpaceCast(LLVMValueRef ConstantVal,
LLVMTypeRef ToType) {
return wrap(ConstantExpr::getAddrSpaceCast(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstZExtOrBitCast(LLVMValueRef ConstantVal,
LLVMTypeRef ToType) {
return wrap(ConstantExpr::getZExtOrBitCast(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstSExtOrBitCast(LLVMValueRef ConstantVal,
LLVMTypeRef ToType) {
return wrap(ConstantExpr::getSExtOrBitCast(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstTruncOrBitCast(LLVMValueRef ConstantVal,
LLVMTypeRef ToType) {
return wrap(ConstantExpr::getTruncOrBitCast(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstPointerCast(LLVMValueRef ConstantVal,
LLVMTypeRef ToType) {
return wrap(ConstantExpr::getPointerCast(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstIntCast(LLVMValueRef ConstantVal, LLVMTypeRef ToType,
LLVMBool isSigned) {
return wrap(ConstantExpr::getIntegerCast(unwrap<Constant>(ConstantVal),
unwrap(ToType), isSigned));
}
LLVMValueRef LLVMConstFPCast(LLVMValueRef ConstantVal, LLVMTypeRef ToType) {
return wrap(ConstantExpr::getFPCast(unwrap<Constant>(ConstantVal),
unwrap(ToType)));
}
LLVMValueRef LLVMConstSelect(LLVMValueRef ConstantCondition,
LLVMValueRef ConstantIfTrue,
LLVMValueRef ConstantIfFalse) {
return wrap(ConstantExpr::getSelect(unwrap<Constant>(ConstantCondition),
unwrap<Constant>(ConstantIfTrue),
unwrap<Constant>(ConstantIfFalse)));
}
LLVMValueRef LLVMConstExtractElement(LLVMValueRef VectorConstant,
LLVMValueRef IndexConstant) {
return wrap(ConstantExpr::getExtractElement(unwrap<Constant>(VectorConstant),
unwrap<Constant>(IndexConstant)));
}
LLVMValueRef LLVMConstInsertElement(LLVMValueRef VectorConstant,
LLVMValueRef ElementValueConstant,
LLVMValueRef IndexConstant) {
return wrap(ConstantExpr::getInsertElement(unwrap<Constant>(VectorConstant),
unwrap<Constant>(ElementValueConstant),
unwrap<Constant>(IndexConstant)));
}
LLVMValueRef LLVMConstShuffleVector(LLVMValueRef VectorAConstant,
LLVMValueRef VectorBConstant,
LLVMValueRef MaskConstant) {
return wrap(ConstantExpr::getShuffleVector(unwrap<Constant>(VectorAConstant),
unwrap<Constant>(VectorBConstant),
unwrap<Constant>(MaskConstant)));
}
LLVMValueRef LLVMConstExtractValue(LLVMValueRef AggConstant, unsigned *IdxList,
unsigned NumIdx) {
return wrap(ConstantExpr::getExtractValue(unwrap<Constant>(AggConstant),
makeArrayRef(IdxList, NumIdx)));
}
LLVMValueRef LLVMConstInsertValue(LLVMValueRef AggConstant,
LLVMValueRef ElementValueConstant,
unsigned *IdxList, unsigned NumIdx) {
return wrap(ConstantExpr::getInsertValue(unwrap<Constant>(AggConstant),
unwrap<Constant>(ElementValueConstant),
makeArrayRef(IdxList, NumIdx)));
}
LLVMValueRef LLVMConstInlineAsm(LLVMTypeRef Ty, const char *AsmString,
const char *Constraints,
LLVMBool HasSideEffects,
LLVMBool IsAlignStack) {
return wrap(InlineAsm::get(dyn_cast<FunctionType>(unwrap(Ty)), AsmString,
Constraints, HasSideEffects, IsAlignStack));
}
LLVMValueRef LLVMBlockAddress(LLVMValueRef F, LLVMBasicBlockRef BB) {
return wrap(BlockAddress::get(unwrap<Function>(F), unwrap(BB)));
}
/*--.. Operations on global variables, functions, and aliases (globals) ....--*/
LLVMModuleRef LLVMGetGlobalParent(LLVMValueRef Global) {
return wrap(unwrap<GlobalValue>(Global)->getParent());
}
LLVMBool LLVMIsDeclaration(LLVMValueRef Global) {
return unwrap<GlobalValue>(Global)->isDeclaration();
}
LLVMLinkage LLVMGetLinkage(LLVMValueRef Global) {
switch (unwrap<GlobalValue>(Global)->getLinkage()) {
case GlobalValue::ExternalLinkage:
return LLVMExternalLinkage;
case GlobalValue::AvailableExternallyLinkage:
return LLVMAvailableExternallyLinkage;
case GlobalValue::LinkOnceAnyLinkage:
return LLVMLinkOnceAnyLinkage;
case GlobalValue::LinkOnceODRLinkage:
return LLVMLinkOnceODRLinkage;
case GlobalValue::WeakAnyLinkage:
return LLVMWeakAnyLinkage;
case GlobalValue::WeakODRLinkage:
return LLVMWeakODRLinkage;
case GlobalValue::AppendingLinkage:
return LLVMAppendingLinkage;
case GlobalValue::InternalLinkage:
return LLVMInternalLinkage;
case GlobalValue::PrivateLinkage:
return LLVMPrivateLinkage;
case GlobalValue::ExternalWeakLinkage:
return LLVMExternalWeakLinkage;
case GlobalValue::CommonLinkage:
return LLVMCommonLinkage;
}
llvm_unreachable("Invalid GlobalValue linkage!");
}
void LLVMSetLinkage(LLVMValueRef Global, LLVMLinkage Linkage) {
GlobalValue *GV = unwrap<GlobalValue>(Global);
switch (Linkage) {
case LLVMExternalLinkage:
GV->setLinkage(GlobalValue::ExternalLinkage);
break;
case LLVMAvailableExternallyLinkage:
GV->setLinkage(GlobalValue::AvailableExternallyLinkage);
break;
case LLVMLinkOnceAnyLinkage:
GV->setLinkage(GlobalValue::LinkOnceAnyLinkage);
break;
case LLVMLinkOnceODRLinkage:
GV->setLinkage(GlobalValue::LinkOnceODRLinkage);
break;
case LLVMLinkOnceODRAutoHideLinkage:
DEBUG(errs() << "LLVMSetLinkage(): LLVMLinkOnceODRAutoHideLinkage is no "
"longer supported.");
break;
case LLVMWeakAnyLinkage:
GV->setLinkage(GlobalValue::WeakAnyLinkage);
break;
case LLVMWeakODRLinkage:
GV->setLinkage(GlobalValue::WeakODRLinkage);
break;
case LLVMAppendingLinkage:
GV->setLinkage(GlobalValue::AppendingLinkage);
break;
case LLVMInternalLinkage:
GV->setLinkage(GlobalValue::InternalLinkage);
break;
case LLVMPrivateLinkage:
GV->setLinkage(GlobalValue::PrivateLinkage);
break;
case LLVMLinkerPrivateLinkage:
GV->setLinkage(GlobalValue::PrivateLinkage);
break;
case LLVMLinkerPrivateWeakLinkage:
GV->setLinkage(GlobalValue::PrivateLinkage);
break;
case LLVMDLLImportLinkage:
DEBUG(errs()
<< "LLVMSetLinkage(): LLVMDLLImportLinkage is no longer supported.");
break;
case LLVMDLLExportLinkage:
DEBUG(errs()
<< "LLVMSetLinkage(): LLVMDLLExportLinkage is no longer supported.");
break;
case LLVMExternalWeakLinkage:
GV->setLinkage(GlobalValue::ExternalWeakLinkage);
break;
case LLVMGhostLinkage:
DEBUG(errs()
<< "LLVMSetLinkage(): LLVMGhostLinkage is no longer supported.");
break;
case LLVMCommonLinkage:
GV->setLinkage(GlobalValue::CommonLinkage);
break;
}
}
const char *LLVMGetSection(LLVMValueRef Global) {
return unwrap<GlobalValue>(Global)->getSection();
}
void LLVMSetSection(LLVMValueRef Global, const char *Section) {
unwrap<GlobalObject>(Global)->setSection(Section);
}
LLVMVisibility LLVMGetVisibility(LLVMValueRef Global) {
return static_cast<LLVMVisibility>(
unwrap<GlobalValue>(Global)->getVisibility());
}
void LLVMSetVisibility(LLVMValueRef Global, LLVMVisibility Viz) {
unwrap<GlobalValue>(Global)
->setVisibility(static_cast<GlobalValue::VisibilityTypes>(Viz));
}
LLVMDLLStorageClass LLVMGetDLLStorageClass(LLVMValueRef Global) {
return static_cast<LLVMDLLStorageClass>(
unwrap<GlobalValue>(Global)->getDLLStorageClass());
}
void LLVMSetDLLStorageClass(LLVMValueRef Global, LLVMDLLStorageClass Class) {
unwrap<GlobalValue>(Global)->setDLLStorageClass(
static_cast<GlobalValue::DLLStorageClassTypes>(Class));
}
LLVMBool LLVMHasUnnamedAddr(LLVMValueRef Global) {
return unwrap<GlobalValue>(Global)->hasUnnamedAddr();
}
void LLVMSetUnnamedAddr(LLVMValueRef Global, LLVMBool HasUnnamedAddr) {
unwrap<GlobalValue>(Global)->setUnnamedAddr(HasUnnamedAddr);
}
/*--.. Operations on global variables, load and store instructions .........--*/
unsigned LLVMGetAlignment(LLVMValueRef V) {
Value *P = unwrap<Value>(V);
if (GlobalValue *GV = dyn_cast<GlobalValue>(P))
return GV->getAlignment();
if (AllocaInst *AI = dyn_cast<AllocaInst>(P))
return AI->getAlignment();
if (LoadInst *LI = dyn_cast<LoadInst>(P))
return LI->getAlignment();
if (StoreInst *SI = dyn_cast<StoreInst>(P))
return SI->getAlignment();
llvm_unreachable(
"only GlobalValue, AllocaInst, LoadInst and StoreInst have alignment");
}
void LLVMSetAlignment(LLVMValueRef V, unsigned Bytes) {
Value *P = unwrap<Value>(V);
if (GlobalObject *GV = dyn_cast<GlobalObject>(P))
GV->setAlignment(Bytes);
else if (AllocaInst *AI = dyn_cast<AllocaInst>(P))
AI->setAlignment(Bytes);
else if (LoadInst *LI = dyn_cast<LoadInst>(P))
LI->setAlignment(Bytes);
else if (StoreInst *SI = dyn_cast<StoreInst>(P))
SI->setAlignment(Bytes);
else
llvm_unreachable(
"only GlobalValue, AllocaInst, LoadInst and StoreInst have alignment");
}
/*--.. Operations on global variables ......................................--*/
LLVMValueRef LLVMAddGlobal(LLVMModuleRef M, LLVMTypeRef Ty, const char *Name) {
return wrap(new GlobalVariable(*unwrap(M), unwrap(Ty), false,
GlobalValue::ExternalLinkage, nullptr, Name));
}
LLVMValueRef LLVMAddGlobalInAddressSpace(LLVMModuleRef M, LLVMTypeRef Ty,
const char *Name,
unsigned AddressSpace) {
return wrap(new GlobalVariable(*unwrap(M), unwrap(Ty), false,
GlobalValue::ExternalLinkage, nullptr, Name,
nullptr, GlobalVariable::NotThreadLocal,
AddressSpace));
}
LLVMValueRef LLVMGetNamedGlobal(LLVMModuleRef M, const char *Name) {
return wrap(unwrap(M)->getNamedGlobal(Name));
}
LLVMValueRef LLVMGetFirstGlobal(LLVMModuleRef M) {
Module *Mod = unwrap(M);
Module::global_iterator I = Mod->global_begin();
if (I == Mod->global_end())
return nullptr;
return wrap(I);
}
LLVMValueRef LLVMGetLastGlobal(LLVMModuleRef M) {
Module *Mod = unwrap(M);
Module::global_iterator I = Mod->global_end();
if (I == Mod->global_begin())
return nullptr;
return wrap(--I);
}
LLVMValueRef LLVMGetNextGlobal(LLVMValueRef GlobalVar) {
GlobalVariable *GV = unwrap<GlobalVariable>(GlobalVar);
Module::global_iterator I = GV;
if (++I == GV->getParent()->global_end())
return nullptr;
return wrap(I);
}
LLVMValueRef LLVMGetPreviousGlobal(LLVMValueRef GlobalVar) {
GlobalVariable *GV = unwrap<GlobalVariable>(GlobalVar);
Module::global_iterator I = GV;
if (I == GV->getParent()->global_begin())
return nullptr;
return wrap(--I);
}
void LLVMDeleteGlobal(LLVMValueRef GlobalVar) {
unwrap<GlobalVariable>(GlobalVar)->eraseFromParent();
}
LLVMValueRef LLVMGetInitializer(LLVMValueRef GlobalVar) {
GlobalVariable* GV = unwrap<GlobalVariable>(GlobalVar);
if ( !GV->hasInitializer() )
return nullptr;
return wrap(GV->getInitializer());
}
void LLVMSetInitializer(LLVMValueRef GlobalVar, LLVMValueRef ConstantVal) {
unwrap<GlobalVariable>(GlobalVar)
->setInitializer(unwrap<Constant>(ConstantVal));
}
LLVMBool LLVMIsThreadLocal(LLVMValueRef GlobalVar) {
return unwrap<GlobalVariable>(GlobalVar)->isThreadLocal();
}
void LLVMSetThreadLocal(LLVMValueRef GlobalVar, LLVMBool IsThreadLocal) {
unwrap<GlobalVariable>(GlobalVar)->setThreadLocal(IsThreadLocal != 0);
}
LLVMBool LLVMIsGlobalConstant(LLVMValueRef GlobalVar) {
return unwrap<GlobalVariable>(GlobalVar)->isConstant();
}
void LLVMSetGlobalConstant(LLVMValueRef GlobalVar, LLVMBool IsConstant) {
unwrap<GlobalVariable>(GlobalVar)->setConstant(IsConstant != 0);
}
LLVMThreadLocalMode LLVMGetThreadLocalMode(LLVMValueRef GlobalVar) {
switch (unwrap<GlobalVariable>(GlobalVar)->getThreadLocalMode()) {
case GlobalVariable::NotThreadLocal:
return LLVMNotThreadLocal;
case GlobalVariable::GeneralDynamicTLSModel:
return LLVMGeneralDynamicTLSModel;
case GlobalVariable::LocalDynamicTLSModel:
return LLVMLocalDynamicTLSModel;
case GlobalVariable::InitialExecTLSModel:
return LLVMInitialExecTLSModel;
case GlobalVariable::LocalExecTLSModel:
return LLVMLocalExecTLSModel;
}
llvm_unreachable("Invalid GlobalVariable thread local mode");
}
void LLVMSetThreadLocalMode(LLVMValueRef GlobalVar, LLVMThreadLocalMode Mode) {
GlobalVariable *GV = unwrap<GlobalVariable>(GlobalVar);
switch (Mode) {
case LLVMNotThreadLocal:
GV->setThreadLocalMode(GlobalVariable::NotThreadLocal);
break;
case LLVMGeneralDynamicTLSModel:
GV->setThreadLocalMode(GlobalVariable::GeneralDynamicTLSModel);
break;
case LLVMLocalDynamicTLSModel:
GV->setThreadLocalMode(GlobalVariable::LocalDynamicTLSModel);
break;
case LLVMInitialExecTLSModel:
GV->setThreadLocalMode(GlobalVariable::InitialExecTLSModel);
break;
case LLVMLocalExecTLSModel:
GV->setThreadLocalMode(GlobalVariable::LocalExecTLSModel);
break;
}
}
LLVMBool LLVMIsExternallyInitialized(LLVMValueRef GlobalVar) {
return unwrap<GlobalVariable>(GlobalVar)->isExternallyInitialized();
}
void LLVMSetExternallyInitialized(LLVMValueRef GlobalVar, LLVMBool IsExtInit) {
unwrap<GlobalVariable>(GlobalVar)->setExternallyInitialized(IsExtInit);
}
/*--.. Operations on aliases ......................................--*/
LLVMValueRef LLVMAddAlias(LLVMModuleRef M, LLVMTypeRef Ty, LLVMValueRef Aliasee,
const char *Name) {
auto *PTy = cast<PointerType>(unwrap(Ty));
return wrap(GlobalAlias::create(PTy, GlobalValue::ExternalLinkage, Name,
unwrap<Constant>(Aliasee), unwrap(M)));
}
/*--.. Operations on functions .............................................--*/
LLVMValueRef LLVMAddFunction(LLVMModuleRef M, const char *Name,
LLVMTypeRef FunctionTy) {
return wrap(Function::Create(unwrap<FunctionType>(FunctionTy),
GlobalValue::ExternalLinkage, Name, unwrap(M)));
}
LLVMValueRef LLVMGetNamedFunction(LLVMModuleRef M, const char *Name) {
return wrap(unwrap(M)->getFunction(Name));
}
LLVMValueRef LLVMGetFirstFunction(LLVMModuleRef M) {
Module *Mod = unwrap(M);
Module::iterator I = Mod->begin();
if (I == Mod->end())
return nullptr;
return wrap(I);
}
LLVMValueRef LLVMGetLastFunction(LLVMModuleRef M) {
Module *Mod = unwrap(M);
Module::iterator I = Mod->end();
if (I == Mod->begin())
return nullptr;
return wrap(--I);
}
LLVMValueRef LLVMGetNextFunction(LLVMValueRef Fn) {
Function *Func = unwrap<Function>(Fn);
Module::iterator I = Func;
if (++I == Func->getParent()->end())
return nullptr;
return wrap(I);
}
LLVMValueRef LLVMGetPreviousFunction(LLVMValueRef Fn) {
Function *Func = unwrap<Function>(Fn);
Module::iterator I = Func;
if (I == Func->getParent()->begin())
return nullptr;
return wrap(--I);
}
void LLVMDeleteFunction(LLVMValueRef Fn) {
unwrap<Function>(Fn)->eraseFromParent();
}
LLVMValueRef LLVMGetPersonalityFn(LLVMValueRef Fn) {
return wrap(unwrap<Function>(Fn)->getPersonalityFn());
}
void LLVMSetPersonalityFn(LLVMValueRef Fn, LLVMValueRef PersonalityFn) {
unwrap<Function>(Fn)->setPersonalityFn(unwrap<Constant>(PersonalityFn));
}
unsigned LLVMGetIntrinsicID(LLVMValueRef Fn) {
if (Function *F = dyn_cast<Function>(unwrap(Fn)))
return F->getIntrinsicID();
return 0;
}
unsigned LLVMGetFunctionCallConv(LLVMValueRef Fn) {
return unwrap<Function>(Fn)->getCallingConv();
}
void LLVMSetFunctionCallConv(LLVMValueRef Fn, unsigned CC) {
return unwrap<Function>(Fn)->setCallingConv(
static_cast<CallingConv::ID>(CC));
}
const char *LLVMGetGC(LLVMValueRef Fn) {
Function *F = unwrap<Function>(Fn);
return F->hasGC()? F->getGC() : nullptr;
}
void LLVMSetGC(LLVMValueRef Fn, const char *GC) {
Function *F = unwrap<Function>(Fn);
if (GC)
F->setGC(GC);
else
F->clearGC();
}
void LLVMAddFunctionAttr(LLVMValueRef Fn, LLVMAttribute PA) {
Function *Func = unwrap<Function>(Fn);
const AttributeSet PAL = Func->getAttributes();
AttrBuilder B(PA);
const AttributeSet PALnew =
PAL.addAttributes(Func->getContext(), AttributeSet::FunctionIndex,
AttributeSet::get(Func->getContext(),
AttributeSet::FunctionIndex, B));
Func->setAttributes(PALnew);
}
void LLVMAddTargetDependentFunctionAttr(LLVMValueRef Fn, const char *A,
const char *V) {
Function *Func = unwrap<Function>(Fn);
AttributeSet::AttrIndex Idx =
AttributeSet::AttrIndex(AttributeSet::FunctionIndex);
AttrBuilder B;
B.addAttribute(A, V);
AttributeSet Set = AttributeSet::get(Func->getContext(), Idx, B);
Func->addAttributes(Idx, Set);
}
void LLVMRemoveFunctionAttr(LLVMValueRef Fn, LLVMAttribute PA) {
Function *Func = unwrap<Function>(Fn);
const AttributeSet PAL = Func->getAttributes();
AttrBuilder B(PA);
const AttributeSet PALnew =
PAL.removeAttributes(Func->getContext(), AttributeSet::FunctionIndex,
AttributeSet::get(Func->getContext(),
AttributeSet::FunctionIndex, B));
Func->setAttributes(PALnew);
}
LLVMAttribute LLVMGetFunctionAttr(LLVMValueRef Fn) {
Function *Func = unwrap<Function>(Fn);
const AttributeSet PAL = Func->getAttributes();
return (LLVMAttribute)PAL.Raw(AttributeSet::FunctionIndex);
}
/*--.. Operations on parameters ............................................--*/
unsigned LLVMCountParams(LLVMValueRef FnRef) {
// This function is strictly redundant to
// LLVMCountParamTypes(LLVMGetElementType(LLVMTypeOf(FnRef)))
return unwrap<Function>(FnRef)->arg_size();
}
void LLVMGetParams(LLVMValueRef FnRef, LLVMValueRef *ParamRefs) {
Function *Fn = unwrap<Function>(FnRef);
for (Function::arg_iterator I = Fn->arg_begin(),
E = Fn->arg_end(); I != E; I++)
*ParamRefs++ = wrap(I);
}
LLVMValueRef LLVMGetParam(LLVMValueRef FnRef, unsigned index) {
Function::arg_iterator AI = unwrap<Function>(FnRef)->arg_begin();
while (index --> 0)
AI++;
return wrap(AI);
}
LLVMValueRef LLVMGetParamParent(LLVMValueRef V) {
return wrap(unwrap<Argument>(V)->getParent());
}
LLVMValueRef LLVMGetFirstParam(LLVMValueRef Fn) {
Function *Func = unwrap<Function>(Fn);
Function::arg_iterator I = Func->arg_begin();
if (I == Func->arg_end())
return nullptr;
return wrap(I);
}
LLVMValueRef LLVMGetLastParam(LLVMValueRef Fn) {
Function *Func = unwrap<Function>(Fn);
Function::arg_iterator I = Func->arg_end();
if (I == Func->arg_begin())
return nullptr;
return wrap(--I);
}
LLVMValueRef LLVMGetNextParam(LLVMValueRef Arg) {
Argument *A = unwrap<Argument>(Arg);
Function::arg_iterator I = A;
if (++I == A->getParent()->arg_end())
return nullptr;
return wrap(I);
}
LLVMValueRef LLVMGetPreviousParam(LLVMValueRef Arg) {
Argument *A = unwrap<Argument>(Arg);
Function::arg_iterator I = A;
if (I == A->getParent()->arg_begin())
return nullptr;
return wrap(--I);
}
void LLVMAddAttribute(LLVMValueRef Arg, LLVMAttribute PA) {
Argument *A = unwrap<Argument>(Arg);
AttrBuilder B(PA);
A->addAttr(AttributeSet::get(A->getContext(), A->getArgNo() + 1, B));
}
void LLVMRemoveAttribute(LLVMValueRef Arg, LLVMAttribute PA) {
Argument *A = unwrap<Argument>(Arg);
AttrBuilder B(PA);
A->removeAttr(AttributeSet::get(A->getContext(), A->getArgNo() + 1, B));
}
LLVMAttribute LLVMGetAttribute(LLVMValueRef Arg) {
Argument *A = unwrap<Argument>(Arg);
return (LLVMAttribute)A->getParent()->getAttributes().
Raw(A->getArgNo()+1);
}
void LLVMSetParamAlignment(LLVMValueRef Arg, unsigned align) {
Argument *A = unwrap<Argument>(Arg);
AttrBuilder B;
B.addAlignmentAttr(align);
A->addAttr(AttributeSet::get(A->getContext(),A->getArgNo() + 1, B));
}
/*--.. Operations on basic blocks ..........................................--*/
LLVMValueRef LLVMBasicBlockAsValue(LLVMBasicBlockRef BB) {
return wrap(static_cast<Value*>(unwrap(BB)));
}
LLVMBool LLVMValueIsBasicBlock(LLVMValueRef Val) {
return isa<BasicBlock>(unwrap(Val));
}
LLVMBasicBlockRef LLVMValueAsBasicBlock(LLVMValueRef Val) {
return wrap(unwrap<BasicBlock>(Val));
}
LLVMValueRef LLVMGetBasicBlockParent(LLVMBasicBlockRef BB) {
return wrap(unwrap(BB)->getParent());
}
LLVMValueRef LLVMGetBasicBlockTerminator(LLVMBasicBlockRef BB) {
return wrap(unwrap(BB)->getTerminator());
}
unsigned LLVMCountBasicBlocks(LLVMValueRef FnRef) {
return unwrap<Function>(FnRef)->size();
}
void LLVMGetBasicBlocks(LLVMValueRef FnRef, LLVMBasicBlockRef *BasicBlocksRefs){
Function *Fn = unwrap<Function>(FnRef);
for (Function::iterator I = Fn->begin(), E = Fn->end(); I != E; I++)
*BasicBlocksRefs++ = wrap(I);
}
LLVMBasicBlockRef LLVMGetEntryBasicBlock(LLVMValueRef Fn) {
return wrap(&unwrap<Function>(Fn)->getEntryBlock());
}
LLVMBasicBlockRef LLVMGetFirstBasicBlock(LLVMValueRef Fn) {
Function *Func = unwrap<Function>(Fn);
Function::iterator I = Func->begin();
if (I == Func->end())
return nullptr;
return wrap(I);
}
LLVMBasicBlockRef LLVMGetLastBasicBlock(LLVMValueRef Fn) {
Function *Func = unwrap<Function>(Fn);
Function::iterator I = Func->end();
if (I == Func->begin())
return nullptr;
return wrap(--I);
}
LLVMBasicBlockRef LLVMGetNextBasicBlock(LLVMBasicBlockRef BB) {
BasicBlock *Block = unwrap(BB);
Function::iterator I = Block;
if (++I == Block->getParent()->end())
return nullptr;
return wrap(I);
}
LLVMBasicBlockRef LLVMGetPreviousBasicBlock(LLVMBasicBlockRef BB) {
BasicBlock *Block = unwrap(BB);
Function::iterator I = Block;
if (I == Block->getParent()->begin())
return nullptr;
return wrap(--I);
}
LLVMBasicBlockRef LLVMAppendBasicBlockInContext(LLVMContextRef C,
LLVMValueRef FnRef,
const char *Name) {
return wrap(BasicBlock::Create(*unwrap(C), Name, unwrap<Function>(FnRef)));
}
LLVMBasicBlockRef LLVMAppendBasicBlock(LLVMValueRef FnRef, const char *Name) {
return LLVMAppendBasicBlockInContext(LLVMGetGlobalContext(), FnRef, Name);
}
LLVMBasicBlockRef LLVMInsertBasicBlockInContext(LLVMContextRef C,
LLVMBasicBlockRef BBRef,
const char *Name) {
BasicBlock *BB = unwrap(BBRef);
return wrap(BasicBlock::Create(*unwrap(C), Name, BB->getParent(), BB));
}
LLVMBasicBlockRef LLVMInsertBasicBlock(LLVMBasicBlockRef BBRef,
const char *Name) {
return LLVMInsertBasicBlockInContext(LLVMGetGlobalContext(), BBRef, Name);
}
void LLVMDeleteBasicBlock(LLVMBasicBlockRef BBRef) {
unwrap(BBRef)->eraseFromParent();
}
void LLVMRemoveBasicBlockFromParent(LLVMBasicBlockRef BBRef) {
unwrap(BBRef)->removeFromParent();
}
void LLVMMoveBasicBlockBefore(LLVMBasicBlockRef BB, LLVMBasicBlockRef MovePos) {
unwrap(BB)->moveBefore(unwrap(MovePos));
}
void LLVMMoveBasicBlockAfter(LLVMBasicBlockRef BB, LLVMBasicBlockRef MovePos) {
unwrap(BB)->moveAfter(unwrap(MovePos));
}
/*--.. Operations on instructions ..........................................--*/
LLVMBasicBlockRef LLVMGetInstructionParent(LLVMValueRef Inst) {
return wrap(unwrap<Instruction>(Inst)->getParent());
}
LLVMValueRef LLVMGetFirstInstruction(LLVMBasicBlockRef BB) {
BasicBlock *Block = unwrap(BB);
BasicBlock::iterator I = Block->begin();
if (I == Block->end())
return nullptr;
return wrap(I);
}
LLVMValueRef LLVMGetLastInstruction(LLVMBasicBlockRef BB) {
BasicBlock *Block = unwrap(BB);
BasicBlock::iterator I = Block->end();
if (I == Block->begin())
return nullptr;
return wrap(--I);
}
LLVMValueRef LLVMGetNextInstruction(LLVMValueRef Inst) {
Instruction *Instr = unwrap<Instruction>(Inst);
BasicBlock::iterator I = Instr;
if (++I == Instr->getParent()->end())
return nullptr;
return wrap(I);
}
LLVMValueRef LLVMGetPreviousInstruction(LLVMValueRef Inst) {
Instruction *Instr = unwrap<Instruction>(Inst);
BasicBlock::iterator I = Instr;
if (I == Instr->getParent()->begin())
return nullptr;
return wrap(--I);
}
void LLVMInstructionEraseFromParent(LLVMValueRef Inst) {
unwrap<Instruction>(Inst)->eraseFromParent();
}
LLVMIntPredicate LLVMGetICmpPredicate(LLVMValueRef Inst) {
if (ICmpInst *I = dyn_cast<ICmpInst>(unwrap(Inst)))
return (LLVMIntPredicate)I->getPredicate();
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(unwrap(Inst)))
if (CE->getOpcode() == Instruction::ICmp)
return (LLVMIntPredicate)CE->getPredicate();
return (LLVMIntPredicate)0;
}
LLVMRealPredicate LLVMGetFCmpPredicate(LLVMValueRef Inst) {
if (FCmpInst *I = dyn_cast<FCmpInst>(unwrap(Inst)))
return (LLVMRealPredicate)I->getPredicate();
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(unwrap(Inst)))
if (CE->getOpcode() == Instruction::FCmp)
return (LLVMRealPredicate)CE->getPredicate();
return (LLVMRealPredicate)0;
}
LLVMOpcode LLVMGetInstructionOpcode(LLVMValueRef Inst) {
if (Instruction *C = dyn_cast<Instruction>(unwrap(Inst)))
return map_to_llvmopcode(C->getOpcode());
return (LLVMOpcode)0;
}
LLVMValueRef LLVMInstructionClone(LLVMValueRef Inst) {
if (Instruction *C = dyn_cast<Instruction>(unwrap(Inst)))
return wrap(C->clone());
return nullptr;
}
/*--.. Call and invoke instructions ........................................--*/
unsigned LLVMGetInstructionCallConv(LLVMValueRef Instr) {
Value *V = unwrap(Instr);
if (CallInst *CI = dyn_cast<CallInst>(V))
return CI->getCallingConv();
if (InvokeInst *II = dyn_cast<InvokeInst>(V))
return II->getCallingConv();
llvm_unreachable("LLVMGetInstructionCallConv applies only to call and invoke!");
}
void LLVMSetInstructionCallConv(LLVMValueRef Instr, unsigned CC) {
Value *V = unwrap(Instr);
if (CallInst *CI = dyn_cast<CallInst>(V))
return CI->setCallingConv(static_cast<CallingConv::ID>(CC));
else if (InvokeInst *II = dyn_cast<InvokeInst>(V))
return II->setCallingConv(static_cast<CallingConv::ID>(CC));
llvm_unreachable("LLVMSetInstructionCallConv applies only to call and invoke!");
}
void LLVMAddInstrAttribute(LLVMValueRef Instr, unsigned index,
LLVMAttribute PA) {
CallSite Call = CallSite(unwrap<Instruction>(Instr));
AttrBuilder B(PA);
Call.setAttributes(
Call.getAttributes().addAttributes(Call->getContext(), index,
AttributeSet::get(Call->getContext(),
index, B)));
}
void LLVMRemoveInstrAttribute(LLVMValueRef Instr, unsigned index,
LLVMAttribute PA) {
CallSite Call = CallSite(unwrap<Instruction>(Instr));
AttrBuilder B(PA);
Call.setAttributes(Call.getAttributes()
.removeAttributes(Call->getContext(), index,
AttributeSet::get(Call->getContext(),
index, B)));
}
void LLVMSetInstrParamAlignment(LLVMValueRef Instr, unsigned index,
unsigned align) {
CallSite Call = CallSite(unwrap<Instruction>(Instr));
AttrBuilder B;
B.addAlignmentAttr(align);
Call.setAttributes(Call.getAttributes()
.addAttributes(Call->getContext(), index,
AttributeSet::get(Call->getContext(),
index, B)));
}
/*--.. Operations on call instructions (only) ..............................--*/
LLVMBool LLVMIsTailCall(LLVMValueRef Call) {
return unwrap<CallInst>(Call)->isTailCall();
}
void LLVMSetTailCall(LLVMValueRef Call, LLVMBool isTailCall) {
unwrap<CallInst>(Call)->setTailCall(isTailCall);
}
/*--.. Operations on terminators ...........................................--*/
unsigned LLVMGetNumSuccessors(LLVMValueRef Term) {
return unwrap<TerminatorInst>(Term)->getNumSuccessors();
}
LLVMBasicBlockRef LLVMGetSuccessor(LLVMValueRef Term, unsigned i) {
return wrap(unwrap<TerminatorInst>(Term)->getSuccessor(i));
}
void LLVMSetSuccessor(LLVMValueRef Term, unsigned i, LLVMBasicBlockRef block) {
return unwrap<TerminatorInst>(Term)->setSuccessor(i,unwrap(block));
}
/*--.. Operations on branch instructions (only) ............................--*/
LLVMBool LLVMIsConditional(LLVMValueRef Branch) {
return unwrap<BranchInst>(Branch)->isConditional();
}
LLVMValueRef LLVMGetCondition(LLVMValueRef Branch) {
return wrap(unwrap<BranchInst>(Branch)->getCondition());
}
void LLVMSetCondition(LLVMValueRef Branch, LLVMValueRef Cond) {
return unwrap<BranchInst>(Branch)->setCondition(unwrap(Cond));
}
/*--.. Operations on switch instructions (only) ............................--*/
LLVMBasicBlockRef LLVMGetSwitchDefaultDest(LLVMValueRef Switch) {
return wrap(unwrap<SwitchInst>(Switch)->getDefaultDest());
}
/*--.. Operations on phi nodes .............................................--*/
void LLVMAddIncoming(LLVMValueRef PhiNode, LLVMValueRef *IncomingValues,
LLVMBasicBlockRef *IncomingBlocks, unsigned Count) {
PHINode *PhiVal = unwrap<PHINode>(PhiNode);
for (unsigned I = 0; I != Count; ++I)
PhiVal->addIncoming(unwrap(IncomingValues[I]), unwrap(IncomingBlocks[I]));
}
unsigned LLVMCountIncoming(LLVMValueRef PhiNode) {
return unwrap<PHINode>(PhiNode)->getNumIncomingValues();
}
LLVMValueRef LLVMGetIncomingValue(LLVMValueRef PhiNode, unsigned Index) {
return wrap(unwrap<PHINode>(PhiNode)->getIncomingValue(Index));
}
LLVMBasicBlockRef LLVMGetIncomingBlock(LLVMValueRef PhiNode, unsigned Index) {
return wrap(unwrap<PHINode>(PhiNode)->getIncomingBlock(Index));
}
/*===-- Instruction builders ----------------------------------------------===*/
LLVMBuilderRef LLVMCreateBuilderInContext(LLVMContextRef C) {
return wrap(new IRBuilder<>(*unwrap(C)));
}
LLVMBuilderRef LLVMCreateBuilder(void) {
return LLVMCreateBuilderInContext(LLVMGetGlobalContext());
}
void LLVMPositionBuilder(LLVMBuilderRef Builder, LLVMBasicBlockRef Block,
LLVMValueRef Instr) {
BasicBlock *BB = unwrap(Block);
Instruction *I = Instr? unwrap<Instruction>(Instr) : (Instruction*) BB->end();
unwrap(Builder)->SetInsertPoint(BB, I);
}
void LLVMPositionBuilderBefore(LLVMBuilderRef Builder, LLVMValueRef Instr) {
Instruction *I = unwrap<Instruction>(Instr);
unwrap(Builder)->SetInsertPoint(I->getParent(), I);
}
void LLVMPositionBuilderAtEnd(LLVMBuilderRef Builder, LLVMBasicBlockRef Block) {
BasicBlock *BB = unwrap(Block);
unwrap(Builder)->SetInsertPoint(BB);
}
LLVMBasicBlockRef LLVMGetInsertBlock(LLVMBuilderRef Builder) {
return wrap(unwrap(Builder)->GetInsertBlock());
}
void LLVMClearInsertionPosition(LLVMBuilderRef Builder) {
unwrap(Builder)->ClearInsertionPoint();
}
void LLVMInsertIntoBuilder(LLVMBuilderRef Builder, LLVMValueRef Instr) {
unwrap(Builder)->Insert(unwrap<Instruction>(Instr));
}
void LLVMInsertIntoBuilderWithName(LLVMBuilderRef Builder, LLVMValueRef Instr,
const char *Name) {
unwrap(Builder)->Insert(unwrap<Instruction>(Instr), Name);
}
void LLVMDisposeBuilder(LLVMBuilderRef Builder) {
delete unwrap(Builder);
}
/*--.. Metadata builders ...................................................--*/
void LLVMSetCurrentDebugLocation(LLVMBuilderRef Builder, LLVMValueRef L) {
MDNode *Loc =
L ? cast<MDNode>(unwrap<MetadataAsValue>(L)->getMetadata()) : nullptr;
unwrap(Builder)->SetCurrentDebugLocation(DebugLoc(Loc));
}
LLVMValueRef LLVMGetCurrentDebugLocation(LLVMBuilderRef Builder) {
LLVMContext &Context = unwrap(Builder)->getContext();
return wrap(MetadataAsValue::get(
Context, unwrap(Builder)->getCurrentDebugLocation().getAsMDNode()));
}
void LLVMSetInstDebugLocation(LLVMBuilderRef Builder, LLVMValueRef Inst) {
unwrap(Builder)->SetInstDebugLocation(unwrap<Instruction>(Inst));
}
/*--.. Instruction builders ................................................--*/
LLVMValueRef LLVMBuildRetVoid(LLVMBuilderRef B) {
return wrap(unwrap(B)->CreateRetVoid());
}
LLVMValueRef LLVMBuildRet(LLVMBuilderRef B, LLVMValueRef V) {
return wrap(unwrap(B)->CreateRet(unwrap(V)));
}
LLVMValueRef LLVMBuildAggregateRet(LLVMBuilderRef B, LLVMValueRef *RetVals,
unsigned N) {
return wrap(unwrap(B)->CreateAggregateRet(unwrap(RetVals), N));
}
LLVMValueRef LLVMBuildBr(LLVMBuilderRef B, LLVMBasicBlockRef Dest) {
return wrap(unwrap(B)->CreateBr(unwrap(Dest)));
}
LLVMValueRef LLVMBuildCondBr(LLVMBuilderRef B, LLVMValueRef If,
LLVMBasicBlockRef Then, LLVMBasicBlockRef Else) {
return wrap(unwrap(B)->CreateCondBr(unwrap(If), unwrap(Then), unwrap(Else)));
}
LLVMValueRef LLVMBuildSwitch(LLVMBuilderRef B, LLVMValueRef V,
LLVMBasicBlockRef Else, unsigned NumCases) {
return wrap(unwrap(B)->CreateSwitch(unwrap(V), unwrap(Else), NumCases));
}
LLVMValueRef LLVMBuildIndirectBr(LLVMBuilderRef B, LLVMValueRef Addr,
unsigned NumDests) {
return wrap(unwrap(B)->CreateIndirectBr(unwrap(Addr), NumDests));
}
LLVMValueRef LLVMBuildInvoke(LLVMBuilderRef B, LLVMValueRef Fn,
LLVMValueRef *Args, unsigned NumArgs,
LLVMBasicBlockRef Then, LLVMBasicBlockRef Catch,
const char *Name) {
return wrap(unwrap(B)->CreateInvoke(unwrap(Fn), unwrap(Then), unwrap(Catch),
makeArrayRef(unwrap(Args), NumArgs),
Name));
}
LLVMValueRef LLVMBuildLandingPad(LLVMBuilderRef B, LLVMTypeRef Ty,
unsigned NumClauses, const char *Name) {
return wrap(unwrap(B)->CreateLandingPad(unwrap(Ty), NumClauses, Name));
}
LLVMValueRef LLVMBuildResume(LLVMBuilderRef B, LLVMValueRef Exn) {
return wrap(unwrap(B)->CreateResume(unwrap(Exn)));
}
LLVMValueRef LLVMBuildUnreachable(LLVMBuilderRef B) {
return wrap(unwrap(B)->CreateUnreachable());
}
void LLVMAddCase(LLVMValueRef Switch, LLVMValueRef OnVal,
LLVMBasicBlockRef Dest) {
unwrap<SwitchInst>(Switch)->addCase(unwrap<ConstantInt>(OnVal), unwrap(Dest));
}
void LLVMAddDestination(LLVMValueRef IndirectBr, LLVMBasicBlockRef Dest) {
unwrap<IndirectBrInst>(IndirectBr)->addDestination(unwrap(Dest));
}
void LLVMAddClause(LLVMValueRef LandingPad, LLVMValueRef ClauseVal) {
unwrap<LandingPadInst>(LandingPad)->
addClause(cast<Constant>(unwrap(ClauseVal)));
}
void LLVMSetCleanup(LLVMValueRef LandingPad, LLVMBool Val) {
unwrap<LandingPadInst>(LandingPad)->setCleanup(Val);
}
/*--.. Arithmetic ..........................................................--*/
LLVMValueRef LLVMBuildAdd(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateAdd(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildNSWAdd(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateNSWAdd(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildNUWAdd(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateNUWAdd(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildFAdd(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateFAdd(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildSub(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateSub(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildNSWSub(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateNSWSub(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildNUWSub(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateNUWSub(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildFSub(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateFSub(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildMul(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateMul(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildNSWMul(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateNSWMul(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildNUWMul(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateNUWMul(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildFMul(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateFMul(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildUDiv(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateUDiv(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildSDiv(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateSDiv(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildExactSDiv(LLVMBuilderRef B, LLVMValueRef LHS,
LLVMValueRef RHS, const char *Name) {
return wrap(unwrap(B)->CreateExactSDiv(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildFDiv(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateFDiv(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildURem(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateURem(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildSRem(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateSRem(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildFRem(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateFRem(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildShl(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateShl(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildLShr(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateLShr(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildAShr(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateAShr(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildAnd(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateAnd(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildOr(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateOr(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildXor(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateXor(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildBinOp(LLVMBuilderRef B, LLVMOpcode Op,
LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateBinOp(Instruction::BinaryOps(map_from_llvmopcode(Op)), unwrap(LHS),
unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildNeg(LLVMBuilderRef B, LLVMValueRef V, const char *Name) {
return wrap(unwrap(B)->CreateNeg(unwrap(V), Name));
}
LLVMValueRef LLVMBuildNSWNeg(LLVMBuilderRef B, LLVMValueRef V,
const char *Name) {
return wrap(unwrap(B)->CreateNSWNeg(unwrap(V), Name));
}
LLVMValueRef LLVMBuildNUWNeg(LLVMBuilderRef B, LLVMValueRef V,
const char *Name) {
return wrap(unwrap(B)->CreateNUWNeg(unwrap(V), Name));
}
LLVMValueRef LLVMBuildFNeg(LLVMBuilderRef B, LLVMValueRef V, const char *Name) {
return wrap(unwrap(B)->CreateFNeg(unwrap(V), Name));
}
LLVMValueRef LLVMBuildNot(LLVMBuilderRef B, LLVMValueRef V, const char *Name) {
return wrap(unwrap(B)->CreateNot(unwrap(V), Name));
}
/*--.. Memory ..............................................................--*/
LLVMValueRef LLVMBuildMalloc(LLVMBuilderRef B, LLVMTypeRef Ty,
const char *Name) {
Type* ITy = Type::getInt32Ty(unwrap(B)->GetInsertBlock()->getContext());
Constant* AllocSize = ConstantExpr::getSizeOf(unwrap(Ty));
AllocSize = ConstantExpr::getTruncOrBitCast(AllocSize, ITy);
Instruction* Malloc = CallInst::CreateMalloc(unwrap(B)->GetInsertBlock(),
ITy, unwrap(Ty), AllocSize,
nullptr, nullptr, "");
return wrap(unwrap(B)->Insert(Malloc, Twine(Name)));
}
LLVMValueRef LLVMBuildArrayMalloc(LLVMBuilderRef B, LLVMTypeRef Ty,
LLVMValueRef Val, const char *Name) {
Type* ITy = Type::getInt32Ty(unwrap(B)->GetInsertBlock()->getContext());
Constant* AllocSize = ConstantExpr::getSizeOf(unwrap(Ty));
AllocSize = ConstantExpr::getTruncOrBitCast(AllocSize, ITy);
Instruction* Malloc = CallInst::CreateMalloc(unwrap(B)->GetInsertBlock(),
ITy, unwrap(Ty), AllocSize,
unwrap(Val), nullptr, "");
return wrap(unwrap(B)->Insert(Malloc, Twine(Name)));
}
LLVMValueRef LLVMBuildAlloca(LLVMBuilderRef B, LLVMTypeRef Ty,
const char *Name) {
return wrap(unwrap(B)->CreateAlloca(unwrap(Ty), nullptr, Name));
}
LLVMValueRef LLVMBuildArrayAlloca(LLVMBuilderRef B, LLVMTypeRef Ty,
LLVMValueRef Val, const char *Name) {
return wrap(unwrap(B)->CreateAlloca(unwrap(Ty), unwrap(Val), Name));
}
LLVMValueRef LLVMBuildFree(LLVMBuilderRef B, LLVMValueRef PointerVal) {
return wrap(unwrap(B)->Insert(
CallInst::CreateFree(unwrap(PointerVal), unwrap(B)->GetInsertBlock())));
}
LLVMValueRef LLVMBuildLoad(LLVMBuilderRef B, LLVMValueRef PointerVal,
const char *Name) {
return wrap(unwrap(B)->CreateLoad(unwrap(PointerVal), Name));
}
LLVMValueRef LLVMBuildStore(LLVMBuilderRef B, LLVMValueRef Val,
LLVMValueRef PointerVal) {
return wrap(unwrap(B)->CreateStore(unwrap(Val), unwrap(PointerVal)));
}
static AtomicOrdering mapFromLLVMOrdering(LLVMAtomicOrdering Ordering) {
switch (Ordering) {
case LLVMAtomicOrderingNotAtomic: return NotAtomic;
case LLVMAtomicOrderingUnordered: return Unordered;
case LLVMAtomicOrderingMonotonic: return Monotonic;
case LLVMAtomicOrderingAcquire: return Acquire;
case LLVMAtomicOrderingRelease: return Release;
case LLVMAtomicOrderingAcquireRelease: return AcquireRelease;
case LLVMAtomicOrderingSequentiallyConsistent:
return SequentiallyConsistent;
}
llvm_unreachable("Invalid LLVMAtomicOrdering value!");
}
LLVMValueRef LLVMBuildFence(LLVMBuilderRef B, LLVMAtomicOrdering Ordering,
LLVMBool isSingleThread, const char *Name) {
return wrap(
unwrap(B)->CreateFence(mapFromLLVMOrdering(Ordering),
isSingleThread ? SingleThread : CrossThread,
Name));
}
LLVMValueRef LLVMBuildGEP(LLVMBuilderRef B, LLVMValueRef Pointer,
LLVMValueRef *Indices, unsigned NumIndices,
const char *Name) {
ArrayRef<Value *> IdxList(unwrap(Indices), NumIndices);
return wrap(unwrap(B)->CreateGEP(nullptr, unwrap(Pointer), IdxList, Name));
}
LLVMValueRef LLVMBuildInBoundsGEP(LLVMBuilderRef B, LLVMValueRef Pointer,
LLVMValueRef *Indices, unsigned NumIndices,
const char *Name) {
ArrayRef<Value *> IdxList(unwrap(Indices), NumIndices);
return wrap(
unwrap(B)->CreateInBoundsGEP(nullptr, unwrap(Pointer), IdxList, Name));
}
LLVMValueRef LLVMBuildStructGEP(LLVMBuilderRef B, LLVMValueRef Pointer,
unsigned Idx, const char *Name) {
return wrap(unwrap(B)->CreateStructGEP(nullptr, unwrap(Pointer), Idx, Name));
}
LLVMValueRef LLVMBuildGlobalString(LLVMBuilderRef B, const char *Str,
const char *Name) {
return wrap(unwrap(B)->CreateGlobalString(Str, Name));
}
LLVMValueRef LLVMBuildGlobalStringPtr(LLVMBuilderRef B, const char *Str,
const char *Name) {
return wrap(unwrap(B)->CreateGlobalStringPtr(Str, Name));
}
LLVMBool LLVMGetVolatile(LLVMValueRef MemAccessInst) {
Value *P = unwrap<Value>(MemAccessInst);
if (LoadInst *LI = dyn_cast<LoadInst>(P))
return LI->isVolatile();
return cast<StoreInst>(P)->isVolatile();
}
void LLVMSetVolatile(LLVMValueRef MemAccessInst, LLVMBool isVolatile) {
Value *P = unwrap<Value>(MemAccessInst);
if (LoadInst *LI = dyn_cast<LoadInst>(P))
return LI->setVolatile(isVolatile);
return cast<StoreInst>(P)->setVolatile(isVolatile);
}
/*--.. Casts ...............................................................--*/
LLVMValueRef LLVMBuildTrunc(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateTrunc(unwrap(Val), unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildZExt(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateZExt(unwrap(Val), unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildSExt(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateSExt(unwrap(Val), unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildFPToUI(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateFPToUI(unwrap(Val), unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildFPToSI(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateFPToSI(unwrap(Val), unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildUIToFP(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateUIToFP(unwrap(Val), unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildSIToFP(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateSIToFP(unwrap(Val), unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildFPTrunc(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateFPTrunc(unwrap(Val), unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildFPExt(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateFPExt(unwrap(Val), unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildPtrToInt(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreatePtrToInt(unwrap(Val), unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildIntToPtr(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateIntToPtr(unwrap(Val), unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildBitCast(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateBitCast(unwrap(Val), unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildAddrSpaceCast(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateAddrSpaceCast(unwrap(Val), unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildZExtOrBitCast(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateZExtOrBitCast(unwrap(Val), unwrap(DestTy),
Name));
}
LLVMValueRef LLVMBuildSExtOrBitCast(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateSExtOrBitCast(unwrap(Val), unwrap(DestTy),
Name));
}
LLVMValueRef LLVMBuildTruncOrBitCast(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateTruncOrBitCast(unwrap(Val), unwrap(DestTy),
Name));
}
LLVMValueRef LLVMBuildCast(LLVMBuilderRef B, LLVMOpcode Op, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateCast(Instruction::CastOps(map_from_llvmopcode(Op)), unwrap(Val),
unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildPointerCast(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreatePointerCast(unwrap(Val), unwrap(DestTy), Name));
}
LLVMValueRef LLVMBuildIntCast(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateIntCast(unwrap(Val), unwrap(DestTy),
/*isSigned*/true, Name));
}
LLVMValueRef LLVMBuildFPCast(LLVMBuilderRef B, LLVMValueRef Val,
LLVMTypeRef DestTy, const char *Name) {
return wrap(unwrap(B)->CreateFPCast(unwrap(Val), unwrap(DestTy), Name));
}
/*--.. Comparisons .........................................................--*/
LLVMValueRef LLVMBuildICmp(LLVMBuilderRef B, LLVMIntPredicate Op,
LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateICmp(static_cast<ICmpInst::Predicate>(Op),
unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildFCmp(LLVMBuilderRef B, LLVMRealPredicate Op,
LLVMValueRef LHS, LLVMValueRef RHS,
const char *Name) {
return wrap(unwrap(B)->CreateFCmp(static_cast<FCmpInst::Predicate>(Op),
unwrap(LHS), unwrap(RHS), Name));
}
/*--.. Miscellaneous instructions ..........................................--*/
LLVMValueRef LLVMBuildPhi(LLVMBuilderRef B, LLVMTypeRef Ty, const char *Name) {
return wrap(unwrap(B)->CreatePHI(unwrap(Ty), 0, Name));
}
LLVMValueRef LLVMBuildCall(LLVMBuilderRef B, LLVMValueRef Fn,
LLVMValueRef *Args, unsigned NumArgs,
const char *Name) {
return wrap(unwrap(B)->CreateCall(unwrap(Fn),
makeArrayRef(unwrap(Args), NumArgs),
Name));
}
LLVMValueRef LLVMBuildSelect(LLVMBuilderRef B, LLVMValueRef If,
LLVMValueRef Then, LLVMValueRef Else,
const char *Name) {
return wrap(unwrap(B)->CreateSelect(unwrap(If), unwrap(Then), unwrap(Else),
Name));
}
LLVMValueRef LLVMBuildVAArg(LLVMBuilderRef B, LLVMValueRef List,
LLVMTypeRef Ty, const char *Name) {
return wrap(unwrap(B)->CreateVAArg(unwrap(List), unwrap(Ty), Name));
}
LLVMValueRef LLVMBuildExtractElement(LLVMBuilderRef B, LLVMValueRef VecVal,
LLVMValueRef Index, const char *Name) {
return wrap(unwrap(B)->CreateExtractElement(unwrap(VecVal), unwrap(Index),
Name));
}
LLVMValueRef LLVMBuildInsertElement(LLVMBuilderRef B, LLVMValueRef VecVal,
LLVMValueRef EltVal, LLVMValueRef Index,
const char *Name) {
return wrap(unwrap(B)->CreateInsertElement(unwrap(VecVal), unwrap(EltVal),
unwrap(Index), Name));
}
LLVMValueRef LLVMBuildShuffleVector(LLVMBuilderRef B, LLVMValueRef V1,
LLVMValueRef V2, LLVMValueRef Mask,
const char *Name) {
return wrap(unwrap(B)->CreateShuffleVector(unwrap(V1), unwrap(V2),
unwrap(Mask), Name));
}
LLVMValueRef LLVMBuildExtractValue(LLVMBuilderRef B, LLVMValueRef AggVal,
unsigned Index, const char *Name) {
return wrap(unwrap(B)->CreateExtractValue(unwrap(AggVal), Index, Name));
}
LLVMValueRef LLVMBuildInsertValue(LLVMBuilderRef B, LLVMValueRef AggVal,
LLVMValueRef EltVal, unsigned Index,
const char *Name) {
return wrap(unwrap(B)->CreateInsertValue(unwrap(AggVal), unwrap(EltVal),
Index, Name));
}
LLVMValueRef LLVMBuildIsNull(LLVMBuilderRef B, LLVMValueRef Val,
const char *Name) {
return wrap(unwrap(B)->CreateIsNull(unwrap(Val), Name));
}
LLVMValueRef LLVMBuildIsNotNull(LLVMBuilderRef B, LLVMValueRef Val,
const char *Name) {
return wrap(unwrap(B)->CreateIsNotNull(unwrap(Val), Name));
}
LLVMValueRef LLVMBuildPtrDiff(LLVMBuilderRef B, LLVMValueRef LHS,
LLVMValueRef RHS, const char *Name) {
return wrap(unwrap(B)->CreatePtrDiff(unwrap(LHS), unwrap(RHS), Name));
}
LLVMValueRef LLVMBuildAtomicRMW(LLVMBuilderRef B,LLVMAtomicRMWBinOp op,
LLVMValueRef PTR, LLVMValueRef Val,
LLVMAtomicOrdering ordering,
LLVMBool singleThread) {
AtomicRMWInst::BinOp intop;
switch (op) {
case LLVMAtomicRMWBinOpXchg: intop = AtomicRMWInst::Xchg; break;
case LLVMAtomicRMWBinOpAdd: intop = AtomicRMWInst::Add; break;
case LLVMAtomicRMWBinOpSub: intop = AtomicRMWInst::Sub; break;
case LLVMAtomicRMWBinOpAnd: intop = AtomicRMWInst::And; break;
case LLVMAtomicRMWBinOpNand: intop = AtomicRMWInst::Nand; break;
case LLVMAtomicRMWBinOpOr: intop = AtomicRMWInst::Or; break;
case LLVMAtomicRMWBinOpXor: intop = AtomicRMWInst::Xor; break;
case LLVMAtomicRMWBinOpMax: intop = AtomicRMWInst::Max; break;
case LLVMAtomicRMWBinOpMin: intop = AtomicRMWInst::Min; break;
case LLVMAtomicRMWBinOpUMax: intop = AtomicRMWInst::UMax; break;
case LLVMAtomicRMWBinOpUMin: intop = AtomicRMWInst::UMin; break;
}
return wrap(unwrap(B)->CreateAtomicRMW(intop, unwrap(PTR), unwrap(Val),
mapFromLLVMOrdering(ordering), singleThread ? SingleThread : CrossThread));
}
/*===-- Module providers --------------------------------------------------===*/
LLVMModuleProviderRef
LLVMCreateModuleProviderForExistingModule(LLVMModuleRef M) {
return reinterpret_cast<LLVMModuleProviderRef>(M);
}
void LLVMDisposeModuleProvider(LLVMModuleProviderRef MP) {
delete unwrap(MP);
}
/*===-- Memory buffers ----------------------------------------------------===*/
LLVMBool LLVMCreateMemoryBufferWithContentsOfFile(
const char *Path,
LLVMMemoryBufferRef *OutMemBuf,
char **OutMessage) {
ErrorOr<std::unique_ptr<MemoryBuffer>> MBOrErr = MemoryBuffer::getFile(Path);
if (std::error_code EC = MBOrErr.getError()) {
*OutMessage = strdup(EC.message().c_str());
return 1;
}
*OutMemBuf = wrap(MBOrErr.get().release());
return 0;
}
LLVMBool LLVMCreateMemoryBufferWithSTDIN(LLVMMemoryBufferRef *OutMemBuf,
char **OutMessage) {
ErrorOr<std::unique_ptr<MemoryBuffer>> MBOrErr = MemoryBuffer::getSTDIN();
if (std::error_code EC = MBOrErr.getError()) {
*OutMessage = strdup(EC.message().c_str());
return 1;
}
*OutMemBuf = wrap(MBOrErr.get().release());
return 0;
}
LLVMMemoryBufferRef LLVMCreateMemoryBufferWithMemoryRange(
const char *InputData,
size_t InputDataLength,
const char *BufferName,
LLVMBool RequiresNullTerminator) {
return wrap(MemoryBuffer::getMemBuffer(StringRef(InputData, InputDataLength),
StringRef(BufferName),
RequiresNullTerminator).release());
}
LLVMMemoryBufferRef LLVMCreateMemoryBufferWithMemoryRangeCopy(
const char *InputData,
size_t InputDataLength,
const char *BufferName) {
return wrap(
MemoryBuffer::getMemBufferCopy(StringRef(InputData, InputDataLength),
StringRef(BufferName)).release());
}
const char *LLVMGetBufferStart(LLVMMemoryBufferRef MemBuf) {
return unwrap(MemBuf)->getBufferStart();
}
size_t LLVMGetBufferSize(LLVMMemoryBufferRef MemBuf) {
return unwrap(MemBuf)->getBufferSize();
}
void LLVMDisposeMemoryBuffer(LLVMMemoryBufferRef MemBuf) {
delete unwrap(MemBuf);
}
/*===-- Pass Registry -----------------------------------------------------===*/
LLVMPassRegistryRef LLVMGetGlobalPassRegistry(void) {
return wrap(PassRegistry::getPassRegistry());
}
/*===-- Pass Manager ------------------------------------------------------===*/
LLVMPassManagerRef LLVMCreatePassManager() {
return wrap(new legacy::PassManager());
}
LLVMPassManagerRef LLVMCreateFunctionPassManagerForModule(LLVMModuleRef M) {
return wrap(new legacy::FunctionPassManager(unwrap(M)));
}
LLVMPassManagerRef LLVMCreateFunctionPassManager(LLVMModuleProviderRef P) {
return LLVMCreateFunctionPassManagerForModule(
reinterpret_cast<LLVMModuleRef>(P));
}
LLVMBool LLVMRunPassManager(LLVMPassManagerRef PM, LLVMModuleRef M) {
return unwrap<legacy::PassManager>(PM)->run(*unwrap(M));
}
LLVMBool LLVMInitializeFunctionPassManager(LLVMPassManagerRef FPM) {
return unwrap<legacy::FunctionPassManager>(FPM)->doInitialization();
}
LLVMBool LLVMRunFunctionPassManager(LLVMPassManagerRef FPM, LLVMValueRef F) {
return unwrap<legacy::FunctionPassManager>(FPM)->run(*unwrap<Function>(F));
}
LLVMBool LLVMFinalizeFunctionPassManager(LLVMPassManagerRef FPM) {
return unwrap<legacy::FunctionPassManager>(FPM)->doFinalization();
}
void LLVMDisposePassManager(LLVMPassManagerRef PM) {
delete unwrap(PM);
}
/*===-- Threading ------------------------------------------------------===*/
LLVMBool LLVMStartMultithreaded() {
return LLVMIsMultithreaded();
}
void LLVMStopMultithreaded() {
}
LLVMBool LLVMIsMultithreaded() {
return llvm_is_multithreaded();
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/DataLayout.cpp | //===-- DataLayout.cpp - Data size & alignment routines --------------------==//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines layout properties related to datatype size/offset/alignment
// information.
//
// This structure should be created once, filled in if the defaults are not
// correct and then passed around by const&. None of the members functions
// require modification to the object.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/DataLayout.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/Triple.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/Mutex.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <cstdlib>
using namespace llvm;
//===----------------------------------------------------------------------===//
// Support for StructLayout
//===----------------------------------------------------------------------===//
StructLayout::StructLayout(StructType *ST, const DataLayout &DL) {
assert(!ST->isOpaque() && "Cannot get layout of opaque structs");
StructAlignment = 0;
StructSize = 0;
NumElements = ST->getNumElements();
// Loop over each of the elements, placing them in memory.
for (unsigned i = 0, e = NumElements; i != e; ++i) {
Type *Ty = ST->getElementType(i);
unsigned TyAlign = ST->isPacked() ? 1 : DL.getABITypeAlignment(Ty);
// Add padding if necessary to align the data element properly.
if ((StructSize & (TyAlign-1)) != 0)
StructSize = RoundUpToAlignment(StructSize, TyAlign);
// Keep track of maximum alignment constraint.
StructAlignment = std::max(TyAlign, StructAlignment);
MemberOffsets[i] = StructSize;
StructSize += DL.getTypeAllocSize(Ty); // Consume space for this data item
}
// Empty structures have alignment of 1 byte.
if (StructAlignment == 0) StructAlignment = 1;
// Add padding to the end of the struct so that it could be put in an array
// and all array elements would be aligned correctly.
if ((StructSize & (StructAlignment-1)) != 0)
StructSize = RoundUpToAlignment(StructSize, StructAlignment);
}
/// getElementContainingOffset - Given a valid offset into the structure,
/// return the structure index that contains it.
unsigned StructLayout::getElementContainingOffset(uint64_t Offset) const {
const uint64_t *SI =
std::upper_bound(&MemberOffsets[0], &MemberOffsets[NumElements], Offset);
assert(SI != &MemberOffsets[0] && "Offset not in structure type!");
--SI;
assert(*SI <= Offset && "upper_bound didn't work");
assert((SI == &MemberOffsets[0] || *(SI-1) <= Offset) &&
(SI+1 == &MemberOffsets[NumElements] || *(SI+1) > Offset) &&
"Upper bound didn't work!");
// Multiple fields can have the same offset if any of them are zero sized.
// For example, in { i32, [0 x i32], i32 }, searching for offset 4 will stop
// at the i32 element, because it is the last element at that offset. This is
// the right one to return, because anything after it will have a higher
// offset, implying that this element is non-empty.
return SI-&MemberOffsets[0];
}
//===----------------------------------------------------------------------===//
// LayoutAlignElem, LayoutAlign support
//===----------------------------------------------------------------------===//
LayoutAlignElem
LayoutAlignElem::get(AlignTypeEnum align_type, unsigned abi_align,
unsigned pref_align, uint32_t bit_width) {
assert(abi_align <= pref_align && "Preferred alignment worse than ABI!");
LayoutAlignElem retval;
retval.AlignType = align_type;
retval.ABIAlign = abi_align;
retval.PrefAlign = pref_align;
retval.TypeBitWidth = bit_width;
return retval;
}
bool
LayoutAlignElem::operator==(const LayoutAlignElem &rhs) const {
return (AlignType == rhs.AlignType
&& ABIAlign == rhs.ABIAlign
&& PrefAlign == rhs.PrefAlign
&& TypeBitWidth == rhs.TypeBitWidth);
}
const LayoutAlignElem
DataLayout::InvalidAlignmentElem = { INVALID_ALIGN, 0, 0, 0 };
//===----------------------------------------------------------------------===//
// PointerAlignElem, PointerAlign support
//===----------------------------------------------------------------------===//
PointerAlignElem
PointerAlignElem::get(uint32_t AddressSpace, unsigned ABIAlign,
unsigned PrefAlign, uint32_t TypeByteWidth) {
assert(ABIAlign <= PrefAlign && "Preferred alignment worse than ABI!");
PointerAlignElem retval;
retval.AddressSpace = AddressSpace;
retval.ABIAlign = ABIAlign;
retval.PrefAlign = PrefAlign;
retval.TypeByteWidth = TypeByteWidth;
return retval;
}
bool
PointerAlignElem::operator==(const PointerAlignElem &rhs) const {
return (ABIAlign == rhs.ABIAlign
&& AddressSpace == rhs.AddressSpace
&& PrefAlign == rhs.PrefAlign
&& TypeByteWidth == rhs.TypeByteWidth);
}
const PointerAlignElem
DataLayout::InvalidPointerElem = { 0U, 0U, 0U, ~0U };
//===----------------------------------------------------------------------===//
// DataLayout Class Implementation
//===----------------------------------------------------------------------===//
const char *DataLayout::getManglingComponent(const Triple &T) {
if (T.isOSBinFormatMachO())
return "-m:o";
if (T.isOSWindows() && T.isOSBinFormatCOFF())
return T.getArch() == Triple::x86 ? "-m:x" : "-m:w";
return "-m:e";
}
static const LayoutAlignElem DefaultAlignments[] = {
{ INTEGER_ALIGN, 1, 1, 1 }, // i1
{ INTEGER_ALIGN, 8, 1, 1 }, // i8
{ INTEGER_ALIGN, 16, 2, 2 }, // i16
{ INTEGER_ALIGN, 32, 4, 4 }, // i32
{ INTEGER_ALIGN, 64, 4, 8 }, // i64
{ FLOAT_ALIGN, 16, 2, 2 }, // half
{ FLOAT_ALIGN, 32, 4, 4 }, // float
{ FLOAT_ALIGN, 64, 8, 8 }, // double
{ FLOAT_ALIGN, 128, 16, 16 }, // ppcf128, quad, ...
{ VECTOR_ALIGN, 64, 8, 8 }, // v2i32, v1i64, ...
{ VECTOR_ALIGN, 128, 16, 16 }, // v16i8, v8i16, v4i32, ...
{ AGGREGATE_ALIGN, 0, 0, 8 } // struct
};
void DataLayout::reset(StringRef Desc) {
clear();
LayoutMap = nullptr;
BigEndian = false;
StackNaturalAlign = 0;
ManglingMode = MM_None;
for (const LayoutAlignElem &E : DefaultAlignments) {
setAlignment((AlignTypeEnum)E.AlignType, E.ABIAlign, E.PrefAlign,
E.TypeBitWidth);
}
setPointerAlignment(0, 8, 8, 8);
parseSpecifier(Desc);
}
/// Checked version of split, to ensure mandatory subparts.
static std::pair<StringRef, StringRef> split(StringRef Str, char Separator) {
assert(!Str.empty() && "parse error, string can't be empty here");
std::pair<StringRef, StringRef> Split = Str.split(Separator);
if (Split.second.empty() && Split.first != Str)
report_fatal_error("Trailing separator in datalayout string");
if (!Split.second.empty() && Split.first.empty())
report_fatal_error("Expected token before separator in datalayout string");
return Split;
}
/// Get an unsigned integer, including error checks.
static unsigned getInt(StringRef R) {
unsigned Result;
bool error = R.getAsInteger(10, Result); (void)error;
if (error)
report_fatal_error("not a number, or does not fit in an unsigned int");
return Result;
}
/// Convert bits into bytes. Assert if not a byte width multiple.
static unsigned inBytes(unsigned Bits) {
if (Bits % 8)
report_fatal_error("number of bits must be a byte width multiple");
return Bits / 8;
}
void DataLayout::parseSpecifier(StringRef Desc) {
StringRepresentation = Desc;
while (!Desc.empty()) {
// Split at '-'.
std::pair<StringRef, StringRef> Split = split(Desc, '-');
Desc = Split.second;
// Split at ':'.
Split = split(Split.first, ':');
// Aliases used below.
StringRef &Tok = Split.first; // Current token.
StringRef &Rest = Split.second; // The rest of the string.
char Specifier = Tok.front();
Tok = Tok.substr(1);
switch (Specifier) {
case 's':
// Ignored for backward compatibility.
// FIXME: remove this on LLVM 4.0.
break;
case 'E':
BigEndian = true;
break;
case 'e':
BigEndian = false;
break;
case 'p': {
// Address space.
unsigned AddrSpace = Tok.empty() ? 0 : getInt(Tok);
if (!isUInt<24>(AddrSpace))
report_fatal_error("Invalid address space, must be a 24bit integer");
// Size.
if (Rest.empty())
report_fatal_error(
"Missing size specification for pointer in datalayout string");
Split = split(Rest, ':');
unsigned PointerMemSize = inBytes(getInt(Tok));
if (!PointerMemSize)
report_fatal_error("Invalid pointer size of 0 bytes");
// ABI alignment.
if (Rest.empty())
report_fatal_error(
"Missing alignment specification for pointer in datalayout string");
Split = split(Rest, ':');
unsigned PointerABIAlign = inBytes(getInt(Tok));
if (!isPowerOf2_64(PointerABIAlign))
report_fatal_error(
"Pointer ABI alignment must be a power of 2");
// Preferred alignment.
unsigned PointerPrefAlign = PointerABIAlign;
if (!Rest.empty()) {
Split = split(Rest, ':');
PointerPrefAlign = inBytes(getInt(Tok));
if (!isPowerOf2_64(PointerPrefAlign))
report_fatal_error(
"Pointer preferred alignment must be a power of 2");
}
setPointerAlignment(AddrSpace, PointerABIAlign, PointerPrefAlign,
PointerMemSize);
break;
}
case 'i':
case 'v':
case 'f':
case 'a': {
AlignTypeEnum AlignType;
switch (Specifier) {
default:
case 'i': AlignType = INTEGER_ALIGN; break;
case 'v': AlignType = VECTOR_ALIGN; break;
case 'f': AlignType = FLOAT_ALIGN; break;
case 'a': AlignType = AGGREGATE_ALIGN; break;
}
// Bit size.
unsigned Size = Tok.empty() ? 0 : getInt(Tok);
if (AlignType == AGGREGATE_ALIGN && Size != 0)
report_fatal_error(
"Sized aggregate specification in datalayout string");
// ABI alignment.
if (Rest.empty())
report_fatal_error(
"Missing alignment specification in datalayout string");
Split = split(Rest, ':');
unsigned ABIAlign = inBytes(getInt(Tok));
if (AlignType != AGGREGATE_ALIGN && !ABIAlign)
report_fatal_error(
"ABI alignment specification must be >0 for non-aggregate types");
// Preferred alignment.
unsigned PrefAlign = ABIAlign;
if (!Rest.empty()) {
Split = split(Rest, ':');
PrefAlign = inBytes(getInt(Tok));
}
setAlignment(AlignType, ABIAlign, PrefAlign, Size);
break;
}
case 'n': // Native integer types.
for (;;) {
unsigned Width = getInt(Tok);
if (Width == 0)
report_fatal_error(
"Zero width native integer type in datalayout string");
LegalIntWidths.push_back(Width);
if (Rest.empty())
break;
Split = split(Rest, ':');
}
break;
case 'S': { // Stack natural alignment.
StackNaturalAlign = inBytes(getInt(Tok));
break;
}
case 'm':
if (!Tok.empty())
report_fatal_error("Unexpected trailing characters after mangling specifier in datalayout string");
if (Rest.empty())
report_fatal_error("Expected mangling specifier in datalayout string");
if (Rest.size() > 1)
report_fatal_error("Unknown mangling specifier in datalayout string");
switch(Rest[0]) {
default:
report_fatal_error("Unknown mangling in datalayout string");
case 'e':
ManglingMode = MM_ELF;
break;
case 'o':
ManglingMode = MM_MachO;
break;
case 'm':
ManglingMode = MM_Mips;
break;
case 'w':
ManglingMode = MM_WinCOFF;
break;
case 'x':
ManglingMode = MM_WinCOFFX86;
break;
}
break;
default:
report_fatal_error("Unknown specifier in datalayout string");
break;
}
}
}
DataLayout::DataLayout(const Module *M) : LayoutMap(nullptr) {
init(M);
}
void DataLayout::init(const Module *M) { *this = M->getDataLayout(); }
bool DataLayout::operator==(const DataLayout &Other) const {
bool Ret = BigEndian == Other.BigEndian &&
StackNaturalAlign == Other.StackNaturalAlign &&
ManglingMode == Other.ManglingMode &&
LegalIntWidths == Other.LegalIntWidths &&
Alignments == Other.Alignments && Pointers == Other.Pointers;
// Note: getStringRepresentation() might differs, it is not canonicalized
return Ret;
}
void
DataLayout::setAlignment(AlignTypeEnum align_type, unsigned abi_align,
unsigned pref_align, uint32_t bit_width) {
if (!isUInt<24>(bit_width))
report_fatal_error("Invalid bit width, must be a 24bit integer");
if (!isUInt<16>(abi_align))
report_fatal_error("Invalid ABI alignment, must be a 16bit integer");
if (!isUInt<16>(pref_align))
report_fatal_error("Invalid preferred alignment, must be a 16bit integer");
if (abi_align != 0 && !isPowerOf2_64(abi_align))
report_fatal_error("Invalid ABI alignment, must be a power of 2");
if (pref_align != 0 && !isPowerOf2_64(pref_align))
report_fatal_error("Invalid preferred alignment, must be a power of 2");
if (pref_align < abi_align)
report_fatal_error(
"Preferred alignment cannot be less than the ABI alignment");
for (LayoutAlignElem &Elem : Alignments) {
if (Elem.AlignType == (unsigned)align_type &&
Elem.TypeBitWidth == bit_width) {
// Update the abi, preferred alignments.
Elem.ABIAlign = abi_align;
Elem.PrefAlign = pref_align;
return;
}
}
Alignments.push_back(LayoutAlignElem::get(align_type, abi_align,
pref_align, bit_width));
}
DataLayout::PointersTy::iterator
DataLayout::findPointerLowerBound(uint32_t AddressSpace) {
return std::lower_bound(Pointers.begin(), Pointers.end(), AddressSpace,
[](const PointerAlignElem &A, uint32_t AddressSpace) {
return A.AddressSpace < AddressSpace;
});
}
void DataLayout::setPointerAlignment(uint32_t AddrSpace, unsigned ABIAlign,
unsigned PrefAlign,
uint32_t TypeByteWidth) {
if (PrefAlign < ABIAlign)
report_fatal_error(
"Preferred alignment cannot be less than the ABI alignment");
PointersTy::iterator I = findPointerLowerBound(AddrSpace);
if (I == Pointers.end() || I->AddressSpace != AddrSpace) {
Pointers.insert(I, PointerAlignElem::get(AddrSpace, ABIAlign, PrefAlign,
TypeByteWidth));
} else {
I->ABIAlign = ABIAlign;
I->PrefAlign = PrefAlign;
I->TypeByteWidth = TypeByteWidth;
}
}
/// getAlignmentInfo - Return the alignment (either ABI if ABIInfo = true or
/// preferred if ABIInfo = false) the layout wants for the specified datatype.
unsigned DataLayout::getAlignmentInfo(AlignTypeEnum AlignType,
uint32_t BitWidth, bool ABIInfo,
Type *Ty) const {
// Check to see if we have an exact match and remember the best match we see.
int BestMatchIdx = -1;
int LargestInt = -1;
for (unsigned i = 0, e = Alignments.size(); i != e; ++i) {
if (Alignments[i].AlignType == (unsigned)AlignType &&
Alignments[i].TypeBitWidth == BitWidth)
return ABIInfo ? Alignments[i].ABIAlign : Alignments[i].PrefAlign;
// The best match so far depends on what we're looking for.
if (AlignType == INTEGER_ALIGN &&
Alignments[i].AlignType == INTEGER_ALIGN) {
// The "best match" for integers is the smallest size that is larger than
// the BitWidth requested.
if (Alignments[i].TypeBitWidth > BitWidth && (BestMatchIdx == -1 ||
Alignments[i].TypeBitWidth < Alignments[BestMatchIdx].TypeBitWidth))
BestMatchIdx = i;
// However, if there isn't one that's larger, then we must use the
// largest one we have (see below)
if (LargestInt == -1 ||
Alignments[i].TypeBitWidth > Alignments[LargestInt].TypeBitWidth)
LargestInt = i;
}
}
// Okay, we didn't find an exact solution. Fall back here depending on what
// is being looked for.
if (BestMatchIdx == -1) {
// If we didn't find an integer alignment, fall back on most conservative.
if (AlignType == INTEGER_ALIGN) {
BestMatchIdx = LargestInt;
} else if (AlignType == VECTOR_ALIGN) {
// By default, use natural alignment for vector types. This is consistent
// with what clang and llvm-gcc do.
unsigned Align = getTypeAllocSize(cast<VectorType>(Ty)->getElementType());
Align *= cast<VectorType>(Ty)->getNumElements();
// If the alignment is not a power of 2, round up to the next power of 2.
// This happens for non-power-of-2 length vectors.
if (Align & (Align-1))
Align = NextPowerOf2(Align);
return Align;
}
}
// If we still couldn't find a reasonable default alignment, fall back
// to a simple heuristic that the alignment is the first power of two
// greater-or-equal to the store size of the type. This is a reasonable
// approximation of reality, and if the user wanted something less
// less conservative, they should have specified it explicitly in the data
// layout.
if (BestMatchIdx == -1) {
unsigned Align = getTypeStoreSize(Ty);
if (Align & (Align-1))
Align = NextPowerOf2(Align);
return Align;
}
// Since we got a "best match" index, just return it.
return ABIInfo ? Alignments[BestMatchIdx].ABIAlign
: Alignments[BestMatchIdx].PrefAlign;
}
namespace {
class StructLayoutMap {
typedef DenseMap<StructType*, StructLayout*> LayoutInfoTy;
LayoutInfoTy LayoutInfo;
public:
~StructLayoutMap() {
// Remove any layouts.
for (const auto &I : LayoutInfo) {
StructLayout *Value = I.second;
Value->~StructLayout();
::operator delete(Value); // HLSL Change: Use overridable operator delete
}
}
StructLayout *&operator[](StructType *STy) {
return LayoutInfo[STy];
}
};
} // end anonymous namespace
void DataLayout::clear() {
LegalIntWidths.clear();
Alignments.clear();
Pointers.clear();
delete static_cast<StructLayoutMap *>(LayoutMap);
LayoutMap = nullptr;
}
DataLayout::~DataLayout() {
clear();
}
const StructLayout *DataLayout::getStructLayout(StructType *Ty) const {
if (!LayoutMap)
LayoutMap = new StructLayoutMap();
StructLayoutMap *STM = static_cast<StructLayoutMap*>(LayoutMap);
StructLayout *&SL = (*STM)[Ty];
if (SL) return SL;
// Otherwise, create the struct layout. Because it is variable length, we
// malloc it, then use placement new.
int NumElts = Ty->getNumElements();
StructLayout *L =
(StructLayout *)::operator new(sizeof(StructLayout)+(NumElts-1) * sizeof(uint64_t)); // HLSL Change: Use overridable operator new
// Set SL before calling StructLayout's ctor. The ctor could cause other
// entries to be added to TheMap, invalidating our reference.
SL = L;
new (L) StructLayout(Ty, *this);
return L;
}
unsigned DataLayout::getPointerABIAlignment(unsigned AS) const {
PointersTy::const_iterator I = findPointerLowerBound(AS);
if (I == Pointers.end() || I->AddressSpace != AS) {
I = findPointerLowerBound(0);
assert(I->AddressSpace == 0);
}
return I->ABIAlign;
}
unsigned DataLayout::getPointerPrefAlignment(unsigned AS) const {
PointersTy::const_iterator I = findPointerLowerBound(AS);
if (I == Pointers.end() || I->AddressSpace != AS) {
I = findPointerLowerBound(0);
assert(I->AddressSpace == 0);
}
return I->PrefAlign;
}
unsigned DataLayout::getPointerSize(unsigned AS) const {
PointersTy::const_iterator I = findPointerLowerBound(AS);
if (I == Pointers.end() || I->AddressSpace != AS) {
I = findPointerLowerBound(0);
assert(I->AddressSpace == 0);
}
return I->TypeByteWidth;
}
unsigned DataLayout::getPointerTypeSizeInBits(Type *Ty) const {
assert(Ty->isPtrOrPtrVectorTy() &&
"This should only be called with a pointer or pointer vector type");
if (Ty->isPointerTy())
return getTypeSizeInBits(Ty);
return getTypeSizeInBits(Ty->getScalarType());
}
/*!
\param abi_or_pref Flag that determines which alignment is returned. true
returns the ABI alignment, false returns the preferred alignment.
\param Ty The underlying type for which alignment is determined.
Get the ABI (\a abi_or_pref == true) or preferred alignment (\a abi_or_pref
== false) for the requested type \a Ty.
*/
unsigned DataLayout::getAlignment(Type *Ty, bool abi_or_pref) const {
int AlignType = -1;
assert(Ty->isSized() && "Cannot getTypeInfo() on a type that is unsized!");
switch (Ty->getTypeID()) {
// Early escape for the non-numeric types.
case Type::LabelTyID:
return (abi_or_pref
? getPointerABIAlignment(0)
: getPointerPrefAlignment(0));
case Type::PointerTyID: {
unsigned AS = cast<PointerType>(Ty)->getAddressSpace();
return (abi_or_pref
? getPointerABIAlignment(AS)
: getPointerPrefAlignment(AS));
}
case Type::ArrayTyID:
return getAlignment(cast<ArrayType>(Ty)->getElementType(), abi_or_pref);
case Type::StructTyID: {
// Packed structure types always have an ABI alignment of one.
if (cast<StructType>(Ty)->isPacked() && abi_or_pref)
return 1;
// Get the layout annotation... which is lazily created on demand.
const StructLayout *Layout = getStructLayout(cast<StructType>(Ty));
unsigned Align = getAlignmentInfo(AGGREGATE_ALIGN, 0, abi_or_pref, Ty);
return std::max(Align, Layout->getAlignment());
}
case Type::IntegerTyID:
AlignType = INTEGER_ALIGN;
break;
case Type::HalfTyID:
case Type::FloatTyID:
case Type::DoubleTyID:
// PPC_FP128TyID and FP128TyID have different data contents, but the
// same size and alignment, so they look the same here.
case Type::PPC_FP128TyID:
case Type::FP128TyID:
case Type::X86_FP80TyID:
AlignType = FLOAT_ALIGN;
break;
case Type::X86_MMXTyID:
case Type::VectorTyID:
AlignType = VECTOR_ALIGN;
// HLSL Change Begins.
return getAlignment(Ty->getVectorElementType(), abi_or_pref);
// HLSL Change Ends.
break;
default:
llvm_unreachable("Bad type for getAlignment!!!");
}
return getAlignmentInfo((AlignTypeEnum)AlignType, getTypeSizeInBits(Ty),
abi_or_pref, Ty);
}
unsigned DataLayout::getABITypeAlignment(Type *Ty) const {
return getAlignment(Ty, true);
}
/// getABIIntegerTypeAlignment - Return the minimum ABI-required alignment for
/// an integer type of the specified bitwidth.
unsigned DataLayout::getABIIntegerTypeAlignment(unsigned BitWidth) const {
return getAlignmentInfo(INTEGER_ALIGN, BitWidth, true, nullptr);
}
unsigned DataLayout::getPrefTypeAlignment(Type *Ty) const {
return getAlignment(Ty, false);
}
unsigned DataLayout::getPreferredTypeAlignmentShift(Type *Ty) const {
unsigned Align = getPrefTypeAlignment(Ty);
assert(!(Align & (Align-1)) && "Alignment is not a power of two!");
return Log2_32(Align);
}
IntegerType *DataLayout::getIntPtrType(LLVMContext &C,
unsigned AddressSpace) const {
return IntegerType::get(C, getPointerSizeInBits(AddressSpace));
}
Type *DataLayout::getIntPtrType(Type *Ty) const {
assert(Ty->isPtrOrPtrVectorTy() &&
"Expected a pointer or pointer vector type.");
unsigned NumBits = getPointerTypeSizeInBits(Ty);
IntegerType *IntTy = IntegerType::get(Ty->getContext(), NumBits);
if (VectorType *VecTy = dyn_cast<VectorType>(Ty))
return VectorType::get(IntTy, VecTy->getNumElements());
return IntTy;
}
Type *DataLayout::getSmallestLegalIntType(LLVMContext &C, unsigned Width) const {
for (unsigned LegalIntWidth : LegalIntWidths)
if (Width <= LegalIntWidth)
return Type::getIntNTy(C, LegalIntWidth);
return nullptr;
}
unsigned DataLayout::getLargestLegalIntTypeSize() const {
auto Max = std::max_element(LegalIntWidths.begin(), LegalIntWidths.end());
return Max != LegalIntWidths.end() ? *Max : 0;
}
uint64_t DataLayout::getIndexedOffset(Type *ptrTy,
ArrayRef<Value *> Indices) const {
Type *Ty = ptrTy;
assert(Ty->isPointerTy() && "Illegal argument for getIndexedOffset()");
uint64_t Result = 0;
generic_gep_type_iterator<Value* const*>
TI = gep_type_begin(ptrTy, Indices);
for (unsigned CurIDX = 0, EndIDX = Indices.size(); CurIDX != EndIDX;
++CurIDX, ++TI) {
if (StructType *STy = dyn_cast<StructType>(*TI)) {
assert(Indices[CurIDX]->getType() ==
Type::getInt32Ty(ptrTy->getContext()) &&
"Illegal struct idx");
unsigned FieldNo = cast<ConstantInt>(Indices[CurIDX])->getZExtValue();
// Get structure layout information...
const StructLayout *Layout = getStructLayout(STy);
// Add in the offset, as calculated by the structure layout info...
Result += Layout->getElementOffset(FieldNo);
// Update Ty to refer to current element
Ty = STy->getElementType(FieldNo);
} else {
// Update Ty to refer to current element
Ty = cast<SequentialType>(Ty)->getElementType();
// Get the array index and the size of each array element.
if (int64_t arrayIdx = cast<ConstantInt>(Indices[CurIDX])->getSExtValue())
Result += (uint64_t)arrayIdx * getTypeAllocSize(Ty);
}
}
return Result;
}
/// getPreferredAlignment - Return the preferred alignment of the specified
/// global. This includes an explicitly requested alignment (if the global
/// has one).
unsigned DataLayout::getPreferredAlignment(const GlobalVariable *GV) const {
Type *ElemType = GV->getType()->getElementType();
unsigned Alignment = getPrefTypeAlignment(ElemType);
unsigned GVAlignment = GV->getAlignment();
if (GVAlignment >= Alignment) {
Alignment = GVAlignment;
} else if (GVAlignment != 0) {
Alignment = std::max(GVAlignment, getABITypeAlignment(ElemType));
}
if (GV->hasInitializer() && GVAlignment == 0) {
if (Alignment < 16) {
// If the global is not external, see if it is large. If so, give it a
// larger alignment.
if (getTypeSizeInBits(ElemType) > 128)
Alignment = 16; // 16-byte alignment.
}
}
return Alignment;
}
/// getPreferredAlignmentLog - Return the preferred alignment of the
/// specified global, returned in log form. This includes an explicitly
/// requested alignment (if the global has one).
unsigned DataLayout::getPreferredAlignmentLog(const GlobalVariable *GV) const {
return Log2_32(getPreferredAlignment(GV));
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/PassRegistry.cpp | //===- PassRegistry.cpp - Pass Registration Implementation ----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the PassRegistry, with which passes are registered on
// initialization, and supports the PassManager in dependency resolution.
//
//===----------------------------------------------------------------------===//
#include "llvm/PassRegistry.h"
#include "llvm/IR/Function.h"
#include "llvm/PassSupport.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/RWMutex.h"
#include <vector>
using namespace llvm;
#ifdef LLVM_ON_WIN32
// HLSL Change Starts - managed statics are tied to DLL lifetime
// Passes exist only in dxcompiler.dll or in a tool like opt that is updated.
//
// These usage patterns imply the following:
// - llvm_shutdown need not allow resurrection, as it's only called at the
// end of main() or at DLL-unload time, and
// - because there is a fixed number of passes (dynamic loading is currently
// unsupported), there is no need to make this thread-safe.
//
// A simple global initialized at DllMain-time will do (still does more work
// than we should likely perform though).
static uint32_t g_PassRegistryTid;
extern "C" uint32_t __stdcall GetCurrentThreadId(void);
static void CheckThreadId() {
if (g_PassRegistryTid == 0)
g_PassRegistryTid = GetCurrentThreadId();
else
assert(g_PassRegistryTid == GetCurrentThreadId() &&
"else updating PassRegistry from incorrect thread");
}
// HLSL Change Ends
#endif
// FIXME: We use ManagedStatic to erase the pass registrar on shutdown.
// Unfortunately, passes are registered with static ctors, and having
// llvm_shutdown clear this map prevents successful resurrection after
// llvm_shutdown is run. Ideally we should find a solution so that we don't
// leak the map, AND can still resurrect after shutdown.
static ManagedStatic<PassRegistry> PassRegistryObj;
PassRegistry *PassRegistry::getPassRegistry() {
return &*PassRegistryObj;
}
//===----------------------------------------------------------------------===//
// Accessors
//
PassRegistry::~PassRegistry() {}
const PassInfo *PassRegistry::getPassInfo(const void *TI) const {
#ifndef LLVM_ON_WIN32 // HLSL Change
sys::SmartScopedReader<true> Guard(Lock);
#endif
MapType::const_iterator I = PassInfoMap.find(TI);
return I != PassInfoMap.end() ? I->second : nullptr;
}
const PassInfo *PassRegistry::getPassInfo(StringRef Arg) const {
#ifndef LLVM_ON_WIN32 // HLSL Change
sys::SmartScopedReader<true> Guard(Lock);
#endif
StringMapType::const_iterator I = PassInfoStringMap.find(Arg);
return I != PassInfoStringMap.end() ? I->second : nullptr;
}
//===----------------------------------------------------------------------===//
// Pass Registration mechanism
//
void PassRegistry::registerPass(const PassInfo &PI, bool ShouldFree) {
#ifdef LLVM_ON_WIN32 // HLSL Change
CheckThreadId();
#else
sys::SmartScopedReader<true> Guard(Lock);
#endif
bool Inserted =
PassInfoMap.insert(std::make_pair(PI.getTypeInfo(), &PI)).second;
assert(Inserted && "Pass registered multiple times!");
(void)Inserted;
PassInfoStringMap[PI.getPassArgument()] = &PI;
// Notify any listeners.
for (auto *Listener : Listeners)
Listener->passRegistered(&PI);
if (ShouldFree)
ToFree.push_back(std::unique_ptr<const PassInfo>(&PI));
}
void PassRegistry::enumerateWith(PassRegistrationListener *L) {
#ifndef LLVM_ON_WIN32 // HLSL Change
sys::SmartScopedReader<true> Guard(Lock);
#endif
for (auto PassInfoPair : PassInfoMap)
L->passEnumerate(PassInfoPair.second);
}
/// Analysis Group Mechanisms.
void PassRegistry::registerAnalysisGroup(const void *InterfaceID,
const void *PassID,
PassInfo &Registeree, bool isDefault,
bool ShouldFree) {
PassInfo *InterfaceInfo = const_cast<PassInfo *>(getPassInfo(InterfaceID));
if (!InterfaceInfo) {
// First reference to Interface, register it now.
registerPass(Registeree);
InterfaceInfo = &Registeree;
}
assert(Registeree.isAnalysisGroup() &&
"Trying to join an analysis group that is a normal pass!");
if (PassID) {
PassInfo *ImplementationInfo = const_cast<PassInfo *>(getPassInfo(PassID));
assert(ImplementationInfo &&
"Must register pass before adding to AnalysisGroup!");
#ifdef LLVM_ON_WIN32 // HLSL Change
CheckThreadId();
#else
sys::SmartScopedReader<true> Guard(Lock);
#endif
// Make sure we keep track of the fact that the implementation implements
// the interface.
ImplementationInfo->addInterfaceImplemented(InterfaceInfo);
if (isDefault) {
assert(InterfaceInfo->getNormalCtor() == nullptr &&
"Default implementation for analysis group already specified!");
assert(
ImplementationInfo->getNormalCtor() &&
"Cannot specify pass as default if it does not have a default ctor");
InterfaceInfo->setNormalCtor(ImplementationInfo->getNormalCtor());
InterfaceInfo->setTargetMachineCtor(
ImplementationInfo->getTargetMachineCtor());
}
}
if (ShouldFree)
ToFree.push_back(std::unique_ptr<const PassInfo>(&Registeree));
}
void PassRegistry::addRegistrationListener(PassRegistrationListener *L) {
#ifdef LLVM_ON_WIN32 // HLSL Change
CheckThreadId();
#else
sys::SmartScopedReader<true> Guard(Lock);
#endif
Listeners.push_back(L);
}
void PassRegistry::removeRegistrationListener(PassRegistrationListener *L) {
#ifdef LLVM_ON_WIN32 // HLSL Change
CheckThreadId();
#else
sys::SmartScopedReader<true> Guard(Lock);
#endif
auto I = std::find(Listeners.begin(), Listeners.end(), L);
Listeners.erase(I);
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/Value.cpp | //===-- Value.cpp - Implement the Value class -----------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the Value, ValueHandle, and User classes.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/Value.h"
#include "LLVMContextImpl.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/Constant.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/InstrTypes.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Operator.h"
#include "llvm/IR/Statepoint.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/IR/ValueSymbolTable.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/raw_ostream.h"
#include <exception> // HLSL Change - add header.
#include <algorithm>
using namespace llvm;
//===----------------------------------------------------------------------===//
// Value Class
//===----------------------------------------------------------------------===//
static inline Type *checkType(Type *Ty) {
assert(Ty && "Value defined with a null type: Error!");
return Ty;
}
Value::Value(Type *ty, unsigned scid)
: VTy(checkType(ty)), UseList(nullptr), SubclassID(scid),
HasValueHandle(0), SubclassOptionalData(0), SubclassData(0),
NumUserOperands(0), IsUsedByMD(false), HasName(false) {
// FIXME: Why isn't this in the subclass gunk??
// Note, we cannot call isa<CallInst> before the CallInst has been
// constructed.
if (SubclassID == Instruction::Call || SubclassID == Instruction::Invoke)
assert((VTy->isFirstClassType() || VTy->isVoidTy() || VTy->isStructTy()) &&
"invalid CallInst type!");
else if (SubclassID != BasicBlockVal &&
(SubclassID < ConstantFirstVal || SubclassID > ConstantLastVal))
assert((VTy->isFirstClassType() || VTy->isVoidTy()) &&
"Cannot create non-first-class values except for constants!");
}
Value::~Value() {
// Notify all ValueHandles (if present) that this value is going away.
if (HasValueHandle)
ValueHandleBase::ValueIsDeleted(this);
if (isUsedByMetadata())
ValueAsMetadata::handleDeletion(this);
#ifndef NDEBUG // Only in -g mode...
// Check to make sure that there are no uses of this value that are still
// around when the value is destroyed. If there are, then we have a dangling
// reference and something is wrong. This code is here to print out where
// the value is still being referenced.
//
if (!use_empty()) {
dbgs() << "While deleting: " << *VTy << " %" << getName() << "\n";
for (auto *U : users())
dbgs() << "Use still stuck around after Def is destroyed:" << *U << "\n";
}
#endif
assert(use_empty() && "Uses remain when a value is destroyed!");
// If this value is named, destroy the name. This should not be in a symtab
// at this point.
destroyValueName();
}
void Value::destroyValueName() {
ValueName *Name = getValueName();
if (Name)
Name->Destroy();
setValueName(nullptr);
}
bool Value::hasNUses(unsigned N) const {
const_use_iterator UI = use_begin(), E = use_end();
for (; N; --N, ++UI)
if (UI == E) return false; // Too few.
return UI == E;
}
bool Value::hasNUsesOrMore(unsigned N) const {
const_use_iterator UI = use_begin(), E = use_end();
for (; N; --N, ++UI)
if (UI == E) return false; // Too few.
return true;
}
bool Value::isUsedInBasicBlock(const BasicBlock *BB) const {
// This can be computed either by scanning the instructions in BB, or by
// scanning the use list of this Value. Both lists can be very long, but
// usually one is quite short.
//
// Scan both lists simultaneously until one is exhausted. This limits the
// search to the shorter list.
BasicBlock::const_iterator BI = BB->begin(), BE = BB->end();
const_user_iterator UI = user_begin(), UE = user_end();
for (; BI != BE && UI != UE; ++BI, ++UI) {
// Scan basic block: Check if this Value is used by the instruction at BI.
if (std::find(BI->op_begin(), BI->op_end(), this) != BI->op_end())
return true;
// Scan use list: Check if the use at UI is in BB.
const Instruction *User = dyn_cast<Instruction>(*UI);
if (User && User->getParent() == BB)
return true;
}
return false;
}
unsigned Value::getNumUses() const {
return (unsigned)std::distance(use_begin(), use_end());
}
static bool getSymTab(Value *V, ValueSymbolTable *&ST) {
ST = nullptr;
if (Instruction *I = dyn_cast<Instruction>(V)) {
if (BasicBlock *P = I->getParent())
if (Function *PP = P->getParent())
ST = &PP->getValueSymbolTable();
} else if (BasicBlock *BB = dyn_cast<BasicBlock>(V)) {
if (Function *P = BB->getParent())
ST = &P->getValueSymbolTable();
} else if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
if (Module *P = GV->getParent())
ST = &P->getValueSymbolTable();
} else if (Argument *A = dyn_cast<Argument>(V)) {
if (Function *P = A->getParent())
ST = &P->getValueSymbolTable();
} else {
assert(isa<Constant>(V) && "Unknown value type!");
return true; // no name is setable for this.
}
return false;
}
ValueName *Value::getValueName() const {
if (!HasName) return nullptr;
LLVMContext &Ctx = getContext();
auto I = Ctx.pImpl->ValueNames.find(this);
assert(I != Ctx.pImpl->ValueNames.end() &&
"No name entry found!");
return I->second;
}
void Value::setValueName(ValueName *VN) {
LLVMContext &Ctx = getContext();
assert(HasName == (bool)Ctx.pImpl->ValueNames.count(this) && // HLSL Change - bool == int
"HasName bit out of sync!");
if (!VN) {
if (HasName)
Ctx.pImpl->ValueNames.erase(this);
HasName = false;
return;
}
// HLSL Change Begin: try/catch to not leak VN on exceptions
try {
Ctx.pImpl->ValueNames[this] = VN;
}
catch (...) {
VN->Destroy();
throw;
}
// HLSL Change End
HasName = true; // HLSL Change - only set this to true after assignment
}
StringRef Value::getName() const {
// Make sure the empty string is still a C string. For historical reasons,
// some clients want to call .data() on the result and expect it to be null
// terminated.
if (!hasName())
return StringRef("", 0);
return getValueName()->getKey();
}
void Value::setNameImpl(const Twine &NewName) {
// Fast path for common IRBuilder case of setName("") when there is no name.
if (NewName.isTriviallyEmpty() && !hasName())
return;
SmallString<256> NameData;
StringRef NameRef = NewName.toStringRef(NameData);
assert(NameRef.find_first_of(0) == StringRef::npos &&
"Null bytes are not allowed in names");
// Name isn't changing?
if (getName() == NameRef)
return;
assert(!getType()->isVoidTy() && "Cannot assign a name to void values!");
// Get the symbol table to update for this object.
ValueSymbolTable *ST;
if (getSymTab(this, ST))
return; // Cannot set a name on this value (e.g. constant).
if (!ST) { // No symbol table to update? Just do the change.
if (NameRef.empty()) {
// Free the name for this value.
destroyValueName();
return;
}
// NOTE: Could optimize for the case the name is shrinking to not deallocate
// then reallocated.
destroyValueName();
// Create the new name.
setValueName(ValueName::Create(NameRef));
getValueName()->setValue(this);
return;
}
// NOTE: Could optimize for the case the name is shrinking to not deallocate
// then reallocated.
if (hasName()) {
// Remove old name.
ST->removeValueName(getValueName());
destroyValueName();
if (NameRef.empty())
return;
}
// Name is changing to something new.
setValueName(ST->createValueName(NameRef, this));
}
void Value::setName(const Twine &NewName) {
setNameImpl(NewName);
if (Function *F = dyn_cast<Function>(this))
F->recalculateIntrinsicID();
}
void Value::takeName(Value *V) {
ValueSymbolTable *ST = nullptr;
// If this value has a name, drop it.
if (hasName()) {
// Get the symtab this is in.
if (getSymTab(this, ST)) {
// We can't set a name on this value, but we need to clear V's name if
// it has one.
if (V->hasName()) V->setName("");
return; // Cannot set a name on this value (e.g. constant).
}
// Remove old name.
if (ST)
ST->removeValueName(getValueName());
destroyValueName();
}
// Now we know that this has no name.
// If V has no name either, we're done.
if (!V->hasName()) return;
// Get this's symtab if we didn't before.
if (!ST) {
if (getSymTab(this, ST)) {
// Clear V's name.
V->setName("");
return; // Cannot set a name on this value (e.g. constant).
}
}
// Get V's ST, this should always succed, because V has a name.
ValueSymbolTable *VST;
bool Failure = getSymTab(V, VST);
assert(!Failure && "V has a name, so it should have a ST!"); (void)Failure;
// If these values are both in the same symtab, we can do this very fast.
// This works even if both values have no symtab yet.
if (ST == VST) {
// Take the name!
setValueName(V->getValueName());
V->setValueName(nullptr);
getValueName()->setValue(this);
return;
}
// Otherwise, things are slightly more complex. Remove V's name from VST and
// then reinsert it into ST.
if (VST)
VST->removeValueName(V->getValueName());
setValueName(V->getValueName());
V->setValueName(nullptr);
getValueName()->setValue(this);
if (ST)
ST->reinsertValue(this);
}
#ifndef NDEBUG
static bool contains(SmallPtrSetImpl<ConstantExpr *> &Cache, ConstantExpr *Expr,
Constant *C) {
if (!Cache.insert(Expr).second)
return false;
for (auto &O : Expr->operands()) {
if (O == C)
return true;
auto *CE = dyn_cast<ConstantExpr>(O);
if (!CE)
continue;
if (contains(Cache, CE, C))
return true;
}
return false;
}
static bool contains(Value *Expr, Value *V) {
if (Expr == V)
return true;
auto *C = dyn_cast<Constant>(V);
if (!C)
return false;
auto *CE = dyn_cast<ConstantExpr>(Expr);
if (!CE)
return false;
SmallPtrSet<ConstantExpr *, 4> Cache;
return contains(Cache, CE, C);
}
#endif
void Value::replaceAllUsesWith(Value *New) {
assert(New && "Value::replaceAllUsesWith(<null>) is invalid!");
assert(!contains(New, this) &&
"this->replaceAllUsesWith(expr(this)) is NOT valid!");
assert(New->getType() == getType() &&
"replaceAllUses of value with new value of different type!");
// Notify all ValueHandles (if present) that this value is going away.
if (HasValueHandle)
ValueHandleBase::ValueIsRAUWd(this, New);
if (isUsedByMetadata())
ValueAsMetadata::handleRAUW(this, New);
while (!use_empty()) {
Use &U = *UseList;
// Must handle Constants specially, we cannot call replaceUsesOfWith on a
// constant because they are uniqued.
if (auto *C = dyn_cast<Constant>(U.getUser())) {
if (!isa<GlobalValue>(C)) {
C->handleOperandChange(this, New, &U);
continue;
}
}
U.set(New);
}
if (BasicBlock *BB = dyn_cast<BasicBlock>(this))
BB->replaceSuccessorsPhiUsesWith(cast<BasicBlock>(New));
}
// Like replaceAllUsesWith except it does not handle constants or basic blocks.
// This routine leaves uses within BB.
void Value::replaceUsesOutsideBlock(Value *New, BasicBlock *BB) {
assert(New && "Value::replaceUsesOutsideBlock(<null>, BB) is invalid!");
assert(!contains(New, this) &&
"this->replaceUsesOutsideBlock(expr(this), BB) is NOT valid!");
assert(New->getType() == getType() &&
"replaceUses of value with new value of different type!");
assert(BB && "Basic block that may contain a use of 'New' must be defined\n");
use_iterator UI = use_begin(), E = use_end();
for (; UI != E;) {
Use &U = *UI;
++UI;
auto *Usr = dyn_cast<Instruction>(U.getUser());
if (Usr && Usr->getParent() == BB)
continue;
U.set(New);
}
return;
}
namespace {
// Various metrics for how much to strip off of pointers.
enum PointerStripKind {
PSK_ZeroIndices,
PSK_ZeroIndicesAndAliases,
PSK_InBoundsConstantIndices,
PSK_InBounds
};
template <PointerStripKind StripKind>
static Value *stripPointerCastsAndOffsets(Value *V) {
if (!V->getType()->isPointerTy())
return V;
// Even though we don't look through PHI nodes, we could be called on an
// instruction in an unreachable block, which may be on a cycle.
SmallPtrSet<Value *, 4> Visited;
Visited.insert(V);
do {
if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
switch (StripKind) {
case PSK_ZeroIndicesAndAliases:
case PSK_ZeroIndices:
if (!GEP->hasAllZeroIndices())
return V;
break;
case PSK_InBoundsConstantIndices:
if (!GEP->hasAllConstantIndices())
return V;
LLVM_FALLTHROUGH; // HLSL Change
case PSK_InBounds:
if (!GEP->isInBounds())
return V;
break;
}
V = GEP->getPointerOperand();
} else if (Operator::getOpcode(V) == Instruction::BitCast ||
Operator::getOpcode(V) == Instruction::AddrSpaceCast) {
V = cast<Operator>(V)->getOperand(0);
} else if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) {
if (StripKind == PSK_ZeroIndices || GA->mayBeOverridden())
return V;
V = GA->getAliasee();
} else {
return V;
}
assert(V->getType()->isPointerTy() && "Unexpected operand type!");
} while (Visited.insert(V).second);
return V;
}
} // namespace
Value *Value::stripPointerCasts() {
return stripPointerCastsAndOffsets<PSK_ZeroIndicesAndAliases>(this);
}
Value *Value::stripPointerCastsNoFollowAliases() {
return stripPointerCastsAndOffsets<PSK_ZeroIndices>(this);
}
Value *Value::stripInBoundsConstantOffsets() {
return stripPointerCastsAndOffsets<PSK_InBoundsConstantIndices>(this);
}
Value *Value::stripAndAccumulateInBoundsConstantOffsets(const DataLayout &DL,
APInt &Offset) {
if (!getType()->isPointerTy())
return this;
assert(Offset.getBitWidth() == DL.getPointerSizeInBits(cast<PointerType>(
getType())->getAddressSpace()) &&
"The offset must have exactly as many bits as our pointer.");
// Even though we don't look through PHI nodes, we could be called on an
// instruction in an unreachable block, which may be on a cycle.
SmallPtrSet<Value *, 4> Visited;
Visited.insert(this);
Value *V = this;
do {
if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
if (!GEP->isInBounds())
return V;
APInt GEPOffset(Offset);
if (!GEP->accumulateConstantOffset(DL, GEPOffset))
return V;
Offset = GEPOffset;
V = GEP->getPointerOperand();
} else if (Operator::getOpcode(V) == Instruction::BitCast ||
Operator::getOpcode(V) == Instruction::AddrSpaceCast) {
V = cast<Operator>(V)->getOperand(0);
} else if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) {
V = GA->getAliasee();
} else {
return V;
}
assert(V->getType()->isPointerTy() && "Unexpected operand type!");
} while (Visited.insert(V).second);
return V;
}
Value *Value::stripInBoundsOffsets() {
return stripPointerCastsAndOffsets<PSK_InBounds>(this);
}
Value *Value::DoPHITranslation(const BasicBlock *CurBB,
const BasicBlock *PredBB) {
PHINode *PN = dyn_cast<PHINode>(this);
if (PN && PN->getParent() == CurBB)
return PN->getIncomingValueForBlock(PredBB);
return this;
}
LLVMContext &Value::getContext() const { return VTy->getContext(); }
void Value::reverseUseList() {
if (!UseList || !UseList->Next)
// No need to reverse 0 or 1 uses.
return;
Use *Head = UseList;
Use *Current = UseList->Next;
Head->Next = nullptr;
while (Current) {
Use *Next = Current->Next;
Current->Next = Head;
Head->setPrev(&Current->Next);
Head = Current;
Current = Next;
}
UseList = Head;
Head->setPrev(&UseList);
}
//===----------------------------------------------------------------------===//
// ValueHandleBase Class
//===----------------------------------------------------------------------===//
void ValueHandleBase::AddToExistingUseList(ValueHandleBase **List) {
assert(List && "Handle list is null?");
// Splice ourselves into the list.
Next = *List;
*List = this;
setPrevPtr(List);
if (Next) {
Next->setPrevPtr(&Next);
assert(getValPtr() == Next->getValPtr() && "Added to wrong list?");
}
}
void ValueHandleBase::AddToExistingUseListAfter(ValueHandleBase *List) {
assert(List && "Must insert after existing node");
Next = List->Next;
setPrevPtr(&List->Next);
List->Next = this;
if (Next)
Next->setPrevPtr(&Next);
}
void ValueHandleBase::AddToUseList() {
assert(getValPtr() && "Null pointer doesn't have a use list!");
LLVMContextImpl *pImpl = getValPtr()->getContext().pImpl;
if (getValPtr()->HasValueHandle) {
// If this value already has a ValueHandle, then it must be in the
// ValueHandles map already.
ValueHandleBase *&Entry = pImpl->ValueHandles[getValPtr()];
assert(Entry && "Value doesn't have any handles?");
AddToExistingUseList(&Entry);
return;
}
// Ok, it doesn't have any handles yet, so we must insert it into the
// DenseMap. However, doing this insertion could cause the DenseMap to
// reallocate itself, which would invalidate all of the PrevP pointers that
// point into the old table. Handle this by checking for reallocation and
// updating the stale pointers only if needed.
DenseMap<Value*, ValueHandleBase*> &Handles = pImpl->ValueHandles;
const void *OldBucketPtr = Handles.getPointerIntoBucketsArray();
ValueHandleBase *&Entry = Handles[getValPtr()];
assert(!Entry && "Value really did already have handles?");
AddToExistingUseList(&Entry);
getValPtr()->HasValueHandle = true;
// If reallocation didn't happen or if this was the first insertion, don't
// walk the table.
if (Handles.isPointerIntoBucketsArray(OldBucketPtr) ||
Handles.size() == 1) {
return;
}
// Okay, reallocation did happen. Fix the Prev Pointers.
for (DenseMap<Value*, ValueHandleBase*>::iterator I = Handles.begin(),
E = Handles.end(); I != E; ++I) {
assert(I->second && I->first == I->second->getValPtr() &&
"List invariant broken!");
I->second->setPrevPtr(&I->second);
}
}
void ValueHandleBase::RemoveFromUseList() {
assert(getValPtr() &&
(std::current_exception() == nullptr ||
getValPtr()->HasValueHandle) && // HLSL Change
"Pointer doesn't have a use list!");
if (!getValPtr()->HasValueHandle)
return; // HLSL Change
// Unlink this from its use list.
ValueHandleBase **PrevPtr = getPrevPtr();
assert(*PrevPtr == this && "List invariant broken");
*PrevPtr = Next;
if (Next) {
assert(Next->getPrevPtr() == &Next && "List invariant broken");
Next->setPrevPtr(PrevPtr);
return;
}
// If the Next pointer was null, then it is possible that this was the last
// ValueHandle watching VP. If so, delete its entry from the ValueHandles
// map.
LLVMContextImpl *pImpl = getValPtr()->getContext().pImpl;
DenseMap<Value*, ValueHandleBase*> &Handles = pImpl->ValueHandles;
if (Handles.isPointerIntoBucketsArray(PrevPtr)) {
Handles.erase(getValPtr());
getValPtr()->HasValueHandle = false;
}
}
void ValueHandleBase::ValueIsDeleted(Value *V) {
assert(V->HasValueHandle && "Should only be called if ValueHandles present");
// Get the linked list base, which is guaranteed to exist since the
// HasValueHandle flag is set.
LLVMContextImpl *pImpl = V->getContext().pImpl;
ValueHandleBase *Entry = pImpl->ValueHandles[V];
assert(Entry && "Value bit set but no entries exist");
// We use a local ValueHandleBase as an iterator so that ValueHandles can add
// and remove themselves from the list without breaking our iteration. This
// is not really an AssertingVH; we just have to give ValueHandleBase a kind.
// Note that we deliberately do not the support the case when dropping a value
// handle results in a new value handle being permanently added to the list
// (as might occur in theory for CallbackVH's): the new value handle will not
// be processed and the checking code will mete out righteous punishment if
// the handle is still present once we have finished processing all the other
// value handles (it is fine to momentarily add then remove a value handle).
for (ValueHandleBase Iterator(Assert, *Entry); Entry; Entry = Iterator.Next) {
Iterator.RemoveFromUseList();
Iterator.AddToExistingUseListAfter(Entry);
assert(Entry->Next == &Iterator && "Loop invariant broken.");
switch (Entry->getKind()) {
case Assert:
break;
case Weak:
case WeakTracking:
// WeakTracking just goes to null, which will unlink it from the list.
Entry->operator=(nullptr);
break;
case Callback:
// Forward to the subclass's implementation.
static_cast<CallbackVH*>(Entry)->deleted();
break;
}
}
// All callbacks, weak references, and assertingVHs should be dropped by now.
if (V->HasValueHandle) {
#ifndef NDEBUG // Only in +Asserts mode...
dbgs() << "While deleting: " << *V->getType() << " %" << V->getName()
<< "\n";
if (pImpl->ValueHandles[V]->getKind() == Assert)
llvm_unreachable("An asserting value handle still pointed to this"
" value!");
#endif
llvm_unreachable("All references to V were not removed?");
}
}
void ValueHandleBase::ValueIsRAUWd(Value *Old, Value *New) {
assert(Old->HasValueHandle &&"Should only be called if ValueHandles present");
assert(Old != New && "Changing value into itself!");
assert(Old->getType() == New->getType() &&
"replaceAllUses of value with new value of different type!");
// Get the linked list base, which is guaranteed to exist since the
// HasValueHandle flag is set.
LLVMContextImpl *pImpl = Old->getContext().pImpl;
ValueHandleBase *Entry = pImpl->ValueHandles[Old];
assert(Entry && "Value bit set but no entries exist");
// We use a local ValueHandleBase as an iterator so that
// ValueHandles can add and remove themselves from the list without
// breaking our iteration. This is not really an AssertingVH; we
// just have to give ValueHandleBase some kind.
for (ValueHandleBase Iterator(Assert, *Entry); Entry; Entry = Iterator.Next) {
Iterator.RemoveFromUseList();
Iterator.AddToExistingUseListAfter(Entry);
assert(Entry->Next == &Iterator && "Loop invariant broken.");
switch (Entry->getKind()) {
case Assert:
case Weak:
// Asserting and Weak handles do not follow RAUW implicitly.
break;
case WeakTracking:
// Weak goes to the new value, which will unlink it from Old's list.
Entry->operator=(New);
break;
case Callback:
// Forward to the subclass's implementation.
static_cast<CallbackVH*>(Entry)->allUsesReplacedWith(New);
break;
}
}
#ifndef NDEBUG
// If any new weak value handles were added while processing the
// list, then complain about it now.
if (Old->HasValueHandle)
for (Entry = pImpl->ValueHandles[Old]; Entry; Entry = Entry->Next)
switch (Entry->getKind()) {
case WeakTracking:
dbgs() << "After RAUW from " << *Old->getType() << " %"
<< Old->getName() << " to " << *New->getType() << " %"
<< New->getName() << "\n";
llvm_unreachable(
"A weak tracking value handle still pointed to the old value!\n");
default:
break;
}
#endif
}
// Pin the vtable to this file.
void CallbackVH::anchor() {}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/LegacyPassManager.cpp | //===- LegacyPassManager.cpp - LLVM Pass Infrastructure Implementation ----===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the legacy LLVM Pass Manager infrastructure.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/IRPrintingPasses.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/IR/LegacyPassManagers.h"
#include "llvm/IR/LegacyPassNameParser.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/Mutex.h"
#include "llvm/Support/TimeValue.h"
#include "llvm/Support/Timer.h"
#include "llvm/Support/TimeProfiler.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <map>
using namespace llvm;
using namespace llvm::legacy;
// See PassManagers.h for Pass Manager infrastructure overview.
//===----------------------------------------------------------------------===//
// Pass debugging information. Often it is useful to find out what pass is
// running when a crash occurs in a utility. When this library is compiled with
// debugging on, a command line option (--debug-pass) is enabled that causes the
// pass name to be printed before it executes.
//
namespace {
// Different debug levels that can be enabled...
enum PassDebugLevel {
Disabled, Arguments, Structure, Executions, Details
};
}
#if 0 // HLSL Change Starts - option pending
static cl::opt<enum PassDebugLevel>
PassDebugging("debug-pass", cl::Hidden,
cl::desc("Print PassManager debugging information"),
cl::values(
clEnumVal(Disabled , "disable debug output"),
clEnumVal(Arguments , "print pass arguments to pass to 'opt'"),
clEnumVal(Structure , "print pass structure before run()"),
clEnumVal(Executions, "print pass name before it is executed"),
clEnumVal(Details , "print pass details when it is executed"),
clEnumValEnd));
#else
static const PassDebugLevel PassDebugging = PassDebugLevel::Disabled;
#endif // HLSL Change Ends
namespace {
typedef llvm::cl::list<const llvm::PassInfo *, bool, PassNameParser>
PassOptionList;
}
#if 0 // HLSL Change Starts - option pending
// Print IR out before/after specified passes.
static PassOptionList
PrintBefore("print-before",
llvm::cl::desc("Print IR before specified passes"),
cl::Hidden);
static PassOptionList
PrintAfter("print-after",
llvm::cl::desc("Print IR after specified passes"),
cl::Hidden);
static cl::opt<bool>
PrintBeforeAll("print-before-all",
llvm::cl::desc("Print IR before each pass"),
cl::init(false));
static cl::opt<bool>
PrintAfterAll("print-after-all",
llvm::cl::desc("Print IR after each pass"),
cl::init(false));
#endif // HLSL Change Ends
/// This is a helper to determine whether to print IR before or
/// after a pass.
#if 0 // HLSL Change
static bool ShouldPrintBeforeOrAfterPass(const PassInfo *PI,
PassOptionList &PassesToPrint) {
for (auto *PassInf : PassesToPrint) {
if (PassInf)
if (PassInf->getPassArgument() == PI->getPassArgument()) {
return true;
}
}
return false;
}
/// This is a utility to check whether a pass should have IR dumped
/// before it.
static bool ShouldPrintBeforePass(const PassInfo *PI) {
return PrintBeforeAll || ShouldPrintBeforeOrAfterPass(PI, PrintBefore);
}
/// This is a utility to check whether a pass should have IR dumped
/// after it.
static bool ShouldPrintAfterPass(const PassInfo *PI) {
return PrintAfterAll || ShouldPrintBeforeOrAfterPass(PI, PrintAfter);
}
#endif // HLSL Change Ends
/// isPassDebuggingExecutionsOrMore - Return true if -debug-pass=Executions
/// or higher is specified.
bool PMDataManager::isPassDebuggingExecutionsOrMore() const {
return PassDebugging >= Executions;
}
void PassManagerPrettyStackEntry::print(raw_ostream &OS) const {
if (!V && !M)
OS << "Releasing pass '";
else
OS << "Running pass '";
OS << P->getPassName() << "'";
if (M) {
OS << " on module '" << M->getModuleIdentifier() << "'.\n";
return;
}
if (!V) {
OS << '\n';
return;
}
OS << " on ";
if (isa<Function>(V))
OS << "function";
else if (isa<BasicBlock>(V))
OS << "basic block";
else
OS << "value";
OS << " '";
V->printAsOperand(OS, /*PrintTy=*/false, M);
OS << "'\n";
}
namespace {
//===----------------------------------------------------------------------===//
// BBPassManager
//
/// BBPassManager manages BasicBlockPass. It batches all the
/// pass together and sequence them to process one basic block before
/// processing next basic block.
class BBPassManager : public PMDataManager, public FunctionPass {
public:
static char ID;
explicit BBPassManager()
: PMDataManager(), FunctionPass(ID) {}
/// Execute all of the passes scheduled for execution. Keep track of
/// whether any of the passes modifies the function, and if so, return true.
bool runOnFunction(Function &F) override;
/// Pass Manager itself does not invalidate any analysis info.
void getAnalysisUsage(AnalysisUsage &Info) const override {
Info.setPreservesAll();
}
bool doInitialization(Module &M) override;
bool doInitialization(Function &F);
bool doFinalization(Module &M) override;
bool doFinalization(Function &F);
PMDataManager *getAsPMDataManager() override { return this; }
Pass *getAsPass() override { return this; }
StringRef getPassName() const override {
return "BasicBlock Pass Manager";
}
// Print passes managed by this manager
void dumpPassStructure(unsigned Offset) override {
dbgs().indent(Offset*2) << "BasicBlockPass Manager\n";
for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
BasicBlockPass *BP = getContainedPass(Index);
BP->dumpPassStructure(Offset + 1);
dumpLastUses(BP, Offset+1);
}
}
BasicBlockPass *getContainedPass(unsigned N) {
assert(N < PassVector.size() && "Pass number out of range!");
BasicBlockPass *BP = static_cast<BasicBlockPass *>(PassVector[N]);
return BP;
}
PassManagerType getPassManagerType() const override {
return PMT_BasicBlockPassManager;
}
};
char BBPassManager::ID = 0;
} // End anonymous namespace
namespace llvm {
namespace legacy {
//===----------------------------------------------------------------------===//
// FunctionPassManagerImpl
//
/// FunctionPassManagerImpl manages FPPassManagers
class FunctionPassManagerImpl : public Pass,
public PMDataManager,
public PMTopLevelManager {
virtual void anchor();
private:
bool wasRun;
public:
static char ID;
explicit FunctionPassManagerImpl() :
Pass(PT_PassManager, ID), PMDataManager(),
PMTopLevelManager(new FPPassManager()), wasRun(false) {}
/// \copydoc FunctionPassManager::add()
void add(Pass *P) {
schedulePass(P);
}
/// createPrinterPass - Get a function printer pass.
Pass *createPrinterPass(raw_ostream &O,
const std::string &Banner) const override {
return createPrintFunctionPass(O, Banner);
}
// Prepare for running an on the fly pass, freeing memory if needed
// from a previous run.
void releaseMemoryOnTheFly();
/// run - Execute all of the passes scheduled for execution. Keep track of
/// whether any of the passes modifies the module, and if so, return true.
bool run(Function &F);
/// doInitialization - Run all of the initializers for the function passes.
///
bool doInitialization(Module &M) override;
/// doFinalization - Run all of the finalizers for the function passes.
///
bool doFinalization(Module &M) override;
PMDataManager *getAsPMDataManager() override { return this; }
Pass *getAsPass() override { return this; }
PassManagerType getTopLevelPassManagerType() override {
return PMT_FunctionPassManager;
}
/// Pass Manager itself does not invalidate any analysis info.
void getAnalysisUsage(AnalysisUsage &Info) const override {
Info.setPreservesAll();
}
FPPassManager *getContainedManager(unsigned N) {
assert(N < PassManagers.size() && "Pass number out of range!");
FPPassManager *FP = static_cast<FPPassManager *>(PassManagers[N]);
return FP;
}
};
void FunctionPassManagerImpl::anchor() {}
char FunctionPassManagerImpl::ID = 0;
} // End of legacy namespace
} // End of llvm namespace
namespace {
//===----------------------------------------------------------------------===//
// MPPassManager
//
/// MPPassManager manages ModulePasses and function pass managers.
/// It batches all Module passes and function pass managers together and
/// sequences them to process one module.
class MPPassManager : public Pass, public PMDataManager {
public:
static char ID;
explicit MPPassManager() :
Pass(PT_PassManager, ID), PMDataManager() { }
// Delete on the fly managers.
~MPPassManager() override {
for (auto &OnTheFlyManager : OnTheFlyManagers) {
FunctionPassManagerImpl *FPP = OnTheFlyManager.second;
delete FPP;
}
}
/// createPrinterPass - Get a module printer pass.
Pass *createPrinterPass(raw_ostream &O,
const std::string &Banner) const override {
return createPrintModulePass(O, Banner);
}
/// run - Execute all of the passes scheduled for execution. Keep track of
/// whether any of the passes modifies the module, and if so, return true.
bool runOnModule(Module &M);
using llvm::Pass::doInitialization;
using llvm::Pass::doFinalization;
/// doInitialization - Run all of the initializers for the module passes.
///
bool doInitialization();
/// doFinalization - Run all of the finalizers for the module passes.
///
bool doFinalization();
/// Pass Manager itself does not invalidate any analysis info.
void getAnalysisUsage(AnalysisUsage &Info) const override {
Info.setPreservesAll();
}
/// Add RequiredPass into list of lower level passes required by pass P.
/// RequiredPass is run on the fly by Pass Manager when P requests it
/// through getAnalysis interface.
void addLowerLevelRequiredPass(Pass *P, Pass *RequiredPass) override;
/// Return function pass corresponding to PassInfo PI, that is
/// required by module pass MP. Instantiate analysis pass, by using
/// its runOnFunction() for function F.
Pass* getOnTheFlyPass(Pass *MP, AnalysisID PI, Function &F) override;
StringRef getPassName() const override {
return "Module Pass Manager";
}
PMDataManager *getAsPMDataManager() override { return this; }
Pass *getAsPass() override { return this; }
// Print passes managed by this manager
void dumpPassStructure(unsigned Offset) override {
dbgs().indent(Offset*2) << "ModulePass Manager\n";
for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
ModulePass *MP = getContainedPass(Index);
MP->dumpPassStructure(Offset + 1);
std::map<Pass *, FunctionPassManagerImpl *>::const_iterator I =
OnTheFlyManagers.find(MP);
if (I != OnTheFlyManagers.end())
I->second->dumpPassStructure(Offset + 2);
dumpLastUses(MP, Offset+1);
}
}
ModulePass *getContainedPass(unsigned N) {
assert(N < PassVector.size() && "Pass number out of range!");
return static_cast<ModulePass *>(PassVector[N]);
}
PassManagerType getPassManagerType() const override {
return PMT_ModulePassManager;
}
private:
/// Collection of on the fly FPPassManagers. These managers manage
/// function passes that are required by module passes.
std::map<Pass *, FunctionPassManagerImpl *> OnTheFlyManagers;
};
char MPPassManager::ID = 0;
} // End anonymous namespace
namespace llvm {
namespace legacy {
//===----------------------------------------------------------------------===//
// PassManagerImpl
//
/// PassManagerImpl manages MPPassManagers
class PassManagerImpl : public Pass,
public PMDataManager,
public PMTopLevelManager {
virtual void anchor();
public:
static char ID;
explicit PassManagerImpl() :
Pass(PT_PassManager, ID), PMDataManager(),
PMTopLevelManager(new MPPassManager()) {}
/// \copydoc PassManager::add()
void add(Pass *P) {
schedulePass(P);
}
/// createPrinterPass - Get a module printer pass.
Pass *createPrinterPass(raw_ostream &O,
const std::string &Banner) const override {
return createPrintModulePass(O, Banner);
}
/// run - Execute all of the passes scheduled for execution. Keep track of
/// whether any of the passes modifies the module, and if so, return true.
bool run(Module &M);
using llvm::Pass::doInitialization;
using llvm::Pass::doFinalization;
/// doInitialization - Run all of the initializers for the module passes.
///
bool doInitialization();
/// doFinalization - Run all of the finalizers for the module passes.
///
bool doFinalization();
/// Pass Manager itself does not invalidate any analysis info.
void getAnalysisUsage(AnalysisUsage &Info) const override {
Info.setPreservesAll();
}
PMDataManager *getAsPMDataManager() override { return this; }
Pass *getAsPass() override { return this; }
PassManagerType getTopLevelPassManagerType() override {
return PMT_ModulePassManager;
}
MPPassManager *getContainedManager(unsigned N) {
assert(N < PassManagers.size() && "Pass number out of range!");
MPPassManager *MP = static_cast<MPPassManager *>(PassManagers[N]);
return MP;
}
};
void PassManagerImpl::anchor() {}
char PassManagerImpl::ID = 0;
} // End of legacy namespace
} // End of llvm namespace
namespace {
//===----------------------------------------------------------------------===//
/// TimingInfo Class - This class is used to calculate information about the
/// amount of time each pass takes to execute. This only happens when
/// -time-passes is enabled on the command line.
///
static ManagedStatic<sys::SmartMutex<true> > TimingInfoMutex;
class TimingInfo {
DenseMap<Pass*, Timer*> TimingData;
TimerGroup TG;
public:
// Use 'create' member to get this.
TimingInfo() : TG("... Pass execution timing report ...") {}
// TimingDtor - Print out information about timing information
~TimingInfo() {
// Delete all of the timers, which accumulate their info into the
// TimerGroup.
for (auto &I : TimingData)
delete I.second;
// TimerGroup is deleted next, printing the report.
}
// createTheTimeInfo - This method either initializes the TheTimeInfo pointer
// to a non-null value (if the -time-passes option is enabled) or it leaves it
// null. It may be called multiple times.
static void createTheTimeInfo();
/// getPassTimer - Return the timer for the specified pass if it exists.
Timer *getPassTimer(Pass *P) {
if (P->getAsPMDataManager())
return nullptr;
sys::SmartScopedLock<true> Lock(*TimingInfoMutex);
Timer *&T = TimingData[P];
if (!T)
T = new Timer(P->getPassName(), TG);
return T;
}
};
} // End of anon namespace
static TimingInfo *TheTimeInfo;
//===----------------------------------------------------------------------===//
// PMTopLevelManager implementation
/// Initialize top level manager. Create first pass manager.
PMTopLevelManager::PMTopLevelManager(PMDataManager *PMDM) {
PMDM->setTopLevelManager(this);
addPassManager(PMDM);
activeStack.push(PMDM);
}
/// Set pass P as the last user of the given analysis passes.
void
PMTopLevelManager::setLastUser(ArrayRef<Pass*> AnalysisPasses, Pass *P) {
unsigned PDepth = 0;
if (P->getResolver())
PDepth = P->getResolver()->getPMDataManager().getDepth();
for (Pass *AP : AnalysisPasses) {
LastUser[AP] = P;
if (P == AP)
continue;
// Update the last users of passes that are required transitive by AP.
AnalysisUsage *AnUsage = findAnalysisUsage(AP);
const AnalysisUsage::VectorType &IDs = AnUsage->getRequiredTransitiveSet();
SmallVector<Pass *, 12> LastUses;
SmallVector<Pass *, 12> LastPMUses;
for (AnalysisUsage::VectorType::const_iterator I = IDs.begin(),
E = IDs.end(); I != E; ++I) {
Pass *AnalysisPass = findAnalysisPass(*I);
assert(AnalysisPass && "Expected analysis pass to exist.");
AnalysisResolver *AR = AnalysisPass->getResolver();
assert(AR && "Expected analysis resolver to exist.");
unsigned APDepth = AR->getPMDataManager().getDepth();
if (PDepth == APDepth)
LastUses.push_back(AnalysisPass);
else if (PDepth > APDepth)
LastPMUses.push_back(AnalysisPass);
}
setLastUser(LastUses, P);
// If this pass has a corresponding pass manager, push higher level
// analysis to this pass manager.
if (P->getResolver())
setLastUser(LastPMUses, P->getResolver()->getPMDataManager().getAsPass());
// If AP is the last user of other passes then make P last user of
// such passes.
for (DenseMap<Pass *, Pass *>::iterator LUI = LastUser.begin(),
LUE = LastUser.end(); LUI != LUE; ++LUI) {
if (LUI->second == AP)
// DenseMap iterator is not invalidated here because
// this is just updating existing entries.
LastUser[LUI->first] = P;
}
}
}
/// Collect passes whose last user is P
void PMTopLevelManager::collectLastUses(SmallVectorImpl<Pass *> &LastUses,
Pass *P) {
DenseMap<Pass *, SmallPtrSet<Pass *, 8> >::iterator DMI =
InversedLastUser.find(P);
if (DMI == InversedLastUser.end())
return;
SmallPtrSet<Pass *, 8> &LU = DMI->second;
for (Pass *LUP : LU) {
LastUses.push_back(LUP);
}
}
AnalysisUsage *PMTopLevelManager::findAnalysisUsage(Pass *P) {
AnalysisUsage *AnUsage = nullptr;
DenseMap<Pass *, AnalysisUsage *>::iterator DMI = AnUsageMap.find(P);
if (DMI != AnUsageMap.end())
AnUsage = DMI->second;
else {
AnUsage = new AnalysisUsage();
std::unique_ptr<AnalysisUsage> AnUsagePtr(AnUsage); // HLSL Change - unique_ptr until added
P->getAnalysisUsage(*AnUsage);
AnUsageMap[P] = AnUsage;
AnUsagePtr.release(); // HLSL Change
}
return AnUsage;
}
/// Schedule pass P for execution. Make sure that passes required by
/// P are run before P is run. Update analysis info maintained by
/// the manager. Remove dead passes. This is a recursive function.
void PMTopLevelManager::schedulePass(Pass *P) {
// TODO : Allocate function manager for this pass, other wise required set
// may be inserted into previous function manager
std::unique_ptr<Pass> PPtr(P); // take ownership locally until we pass it on
// Give pass a chance to prepare the stage.
P->preparePassManager(activeStack);
// If P is an analysis pass and it is available then do not
// generate the analysis again. Stale analysis info should not be
// available at this point.
const PassInfo *PI = findAnalysisPassInfo(P->getPassID());
if (PI && PI->isAnalysis() && findAnalysisPass(P->getPassID())) {
// delete P; // HLSL Change - let PPtr take care of this
return;
}
AnalysisUsage *AnUsage = findAnalysisUsage(P);
bool checkAnalysis = true;
while (checkAnalysis) {
checkAnalysis = false;
const AnalysisUsage::VectorType &RequiredSet = AnUsage->getRequiredSet();
for (AnalysisUsage::VectorType::const_iterator I = RequiredSet.begin(),
E = RequiredSet.end(); I != E; ++I) {
Pass *AnalysisPass = findAnalysisPass(*I);
if (!AnalysisPass) {
const PassInfo *PI = findAnalysisPassInfo(*I);
if (!PI) {
// Pass P is not in the global PassRegistry
dbgs() << "Pass '" << P->getPassName() << "' is not initialized." << "\n";
dbgs() << "Verify if there is a pass dependency cycle." << "\n";
dbgs() << "Required Passes:" << "\n";
for (AnalysisUsage::VectorType::const_iterator I2 = RequiredSet.begin(),
E = RequiredSet.end(); I2 != E && I2 != I; ++I2) {
Pass *AnalysisPass2 = findAnalysisPass(*I2);
if (AnalysisPass2) {
dbgs() << "\t" << AnalysisPass2->getPassName() << "\n";
} else {
dbgs() << "\t" << "Error: Required pass not found! Possible causes:" << "\n";
dbgs() << "\t\t" << "- Pass misconfiguration (e.g.: missing macros)" << "\n";
dbgs() << "\t\t" << "- Corruption of the global PassRegistry" << "\n";
}
}
}
assert(PI && "Expected required passes to be initialized");
AnalysisPass = PI->createPass();
if (P->getPotentialPassManagerType () ==
AnalysisPass->getPotentialPassManagerType())
// Schedule analysis pass that is managed by the same pass manager.
schedulePass(AnalysisPass);
else if (P->getPotentialPassManagerType () >
AnalysisPass->getPotentialPassManagerType()) {
// Schedule analysis pass that is managed by a new manager.
schedulePass(AnalysisPass);
// Recheck analysis passes to ensure that required analyses that
// are already checked are still available.
checkAnalysis = true;
} else
// Do not schedule this analysis. Lower level analysis
// passes are run on the fly.
delete AnalysisPass;
}
}
}
// Now all required passes are available.
if (ImmutablePass *IP = P->getAsImmutablePass()) {
// P is a immutable pass and it will be managed by this
// top level manager. Set up analysis resolver to connect them.
PMDataManager *DM = getAsPMDataManager();
AnalysisResolver *AR = new AnalysisResolver(*DM);
P->setResolver(AR); // HLSL Comment - P takes ownership of AR here
DM->initializeAnalysisImpl(P);
addImmutablePass(IP);
PPtr.release(); // HLSL Change
DM->recordAvailableAnalysis(IP);
return;
}
// HLSL Change - begin
class direct_stderr_stream : public raw_ostream {
uint64_t current_pos() const override { return 0; }
/// See raw_ostream::write_impl.
void write_impl(const char *Ptr, size_t Size) override {
fwrite(Ptr, Size, 1, stderr);
}
};
static direct_stderr_stream stderr_stream;
auto ShouldPrint =
[](const PassInfo *PI, bool AllOpt, std::set<std::string> &ByNameOpt) {
return AllOpt ||
(ByNameOpt.size() && ByNameOpt.count(PI->getPassArgument()));
};
if (PI && !PI->isAnalysis() &&
ShouldPrint(PI, this->HLSLPrintBeforeAll, this->HLSLPrintBefore)) {
Pass *PP = P->createPrinterPass(stderr_stream,
std::string("*** IR Dump Before ") +
P->getPassName().str() + " (" +
PI->getPassArgument() + ") ***");
PP->assignPassManager(activeStack, getTopLevelPassManagerType());
}
// HLSL Change - end
// Add the requested pass to the best available pass manager.
PPtr.release(); // HLSL Change - assignPassManager takes ownership
P->assignPassManager(activeStack, getTopLevelPassManagerType());
// HLSL Change - begin
if (PI && !PI->isAnalysis() &&
ShouldPrint(PI, this->HLSLPrintAfterAll, this->HLSLPrintAfter)) {
Pass *PP = P->createPrinterPass(stderr_stream,
std::string("*** IR Dump After ") +
P->getPassName().str() + " (" +
PI->getPassArgument() + ") ***");
PP->assignPassManager(activeStack, getTopLevelPassManagerType());
}
// HLSL Change - end
}
/// Find the pass that implements Analysis AID. Search immutable
/// passes and all pass managers. If desired pass is not found
/// then return NULL.
Pass *PMTopLevelManager::findAnalysisPass(AnalysisID AID) {
// Check pass managers
for (PMDataManager *PassManager : PassManagers)
if (Pass *P = PassManager->findAnalysisPass(AID, false))
return P;
// Check other pass managers
for (PMDataManager *IndirectPassManager : IndirectPassManagers)
if (Pass *P = IndirectPassManager->findAnalysisPass(AID, false))
return P;
// Check the immutable passes. Iterate in reverse order so that we find
// the most recently registered passes first.
for (auto I = ImmutablePasses.rbegin(), E = ImmutablePasses.rend(); I != E;
++I) {
AnalysisID PI = (*I)->getPassID();
if (PI == AID)
return *I;
// If Pass not found then check the interfaces implemented by Immutable Pass
const PassInfo *PassInf = findAnalysisPassInfo(PI);
assert(PassInf && "Expected all immutable passes to be initialized");
const std::vector<const PassInfo*> &ImmPI =
PassInf->getInterfacesImplemented();
for (const PassInfo *PI : ImmPI)
if (PI->getTypeInfo() == AID)
return *I;
}
return nullptr;
}
const PassInfo *PMTopLevelManager::findAnalysisPassInfo(AnalysisID AID) const {
const PassInfo *&PI = AnalysisPassInfos[AID];
if (!PI)
PI = PassRegistry::getPassRegistry()->getPassInfo(AID);
else
assert(PI == PassRegistry::getPassRegistry()->getPassInfo(AID) &&
"The pass info pointer changed for an analysis ID!");
return PI;
}
// Print passes managed by this top level manager.
void PMTopLevelManager::dumpPasses() const {
if (PassDebugging < Structure)
return;
// Print out the immutable passes
for (unsigned i = 0, e = ImmutablePasses.size(); i != e; ++i) {
ImmutablePasses[i]->dumpPassStructure(0);
}
// Every class that derives from PMDataManager also derives from Pass
// (sometimes indirectly), but there's no inheritance relationship
// between PMDataManager and Pass, so we have to getAsPass to get
// from a PMDataManager* to a Pass*.
for (PMDataManager *Manager : PassManagers)
Manager->getAsPass()->dumpPassStructure(1);
}
void PMTopLevelManager::dumpArguments() const {
if (PassDebugging < Arguments)
return;
dbgs() << "Pass Arguments: ";
for (SmallVectorImpl<ImmutablePass *>::const_iterator I =
ImmutablePasses.begin(), E = ImmutablePasses.end(); I != E; ++I)
if (const PassInfo *PI = findAnalysisPassInfo((*I)->getPassID())) {
assert(PI && "Expected all immutable passes to be initialized");
if (!PI->isAnalysisGroup())
dbgs() << " -" << PI->getPassArgument();
}
for (SmallVectorImpl<PMDataManager *>::const_iterator I =
PassManagers.begin(), E = PassManagers.end(); I != E; ++I)
(*I)->dumpPassArguments();
dbgs() << "\n";
}
void PMTopLevelManager::initializeAllAnalysisInfo() {
for (SmallVectorImpl<PMDataManager *>::iterator I = PassManagers.begin(),
E = PassManagers.end(); I != E; ++I)
(*I)->initializeAnalysisInfo();
// Initailize other pass managers
for (SmallVectorImpl<PMDataManager *>::iterator
I = IndirectPassManagers.begin(), E = IndirectPassManagers.end();
I != E; ++I)
(*I)->initializeAnalysisInfo();
for (DenseMap<Pass *, Pass *>::iterator DMI = LastUser.begin(),
DME = LastUser.end(); DMI != DME; ++DMI) {
DenseMap<Pass *, SmallPtrSet<Pass *, 8> >::iterator InvDMI =
InversedLastUser.find(DMI->second);
if (InvDMI != InversedLastUser.end()) {
SmallPtrSet<Pass *, 8> &L = InvDMI->second;
L.insert(DMI->first);
} else {
SmallPtrSet<Pass *, 8> L; L.insert(DMI->first);
InversedLastUser[DMI->second] = L;
}
}
}
/// Destructor
PMTopLevelManager::~PMTopLevelManager() {
for (SmallVectorImpl<PMDataManager *>::iterator I = PassManagers.begin(),
E = PassManagers.end(); I != E; ++I)
delete *I;
for (SmallVectorImpl<ImmutablePass *>::iterator
I = ImmutablePasses.begin(), E = ImmutablePasses.end(); I != E; ++I)
delete *I;
for (DenseMap<Pass *, AnalysisUsage *>::iterator DMI = AnUsageMap.begin(),
DME = AnUsageMap.end(); DMI != DME; ++DMI)
delete DMI->second;
}
//===----------------------------------------------------------------------===//
// PMDataManager implementation
/// Augement AvailableAnalysis by adding analysis made available by pass P.
void PMDataManager::recordAvailableAnalysis(Pass *P) {
AnalysisID PI = P->getPassID();
AvailableAnalysis[PI] = P;
assert(!AvailableAnalysis.empty());
// This pass is the current implementation of all of the interfaces it
// implements as well.
const PassInfo *PInf = TPM->findAnalysisPassInfo(PI);
if (!PInf) return;
const std::vector<const PassInfo*> &II = PInf->getInterfacesImplemented();
for (unsigned i = 0, e = II.size(); i != e; ++i)
AvailableAnalysis[II[i]->getTypeInfo()] = P;
}
// Return true if P preserves high level analysis used by other
// passes managed by this manager
bool PMDataManager::preserveHigherLevelAnalysis(Pass *P) {
AnalysisUsage *AnUsage = TPM->findAnalysisUsage(P);
if (AnUsage->getPreservesAll())
return true;
const AnalysisUsage::VectorType &PreservedSet = AnUsage->getPreservedSet();
for (SmallVectorImpl<Pass *>::iterator I = HigherLevelAnalysis.begin(),
E = HigherLevelAnalysis.end(); I != E; ++I) {
Pass *P1 = *I;
if (P1->getAsImmutablePass() == nullptr &&
std::find(PreservedSet.begin(), PreservedSet.end(),
P1->getPassID()) ==
PreservedSet.end())
return false;
}
return true;
}
/// verifyPreservedAnalysis -- Verify analysis preserved by pass P.
void PMDataManager::verifyPreservedAnalysis(Pass *P) {
// Don't do this unless assertions are enabled.
#ifdef NDEBUG
return;
#endif
AnalysisUsage *AnUsage = TPM->findAnalysisUsage(P);
const AnalysisUsage::VectorType &PreservedSet = AnUsage->getPreservedSet();
// Verify preserved analysis
for (AnalysisUsage::VectorType::const_iterator I = PreservedSet.begin(),
E = PreservedSet.end(); I != E; ++I) {
AnalysisID AID = *I;
if (Pass *AP = findAnalysisPass(AID, true)) {
TimeRegion PassTimer(getPassTimer(AP));
AP->verifyAnalysis();
}
}
}
/// Remove Analysis not preserved by Pass P
void PMDataManager::removeNotPreservedAnalysis(Pass *P) {
AnalysisUsage *AnUsage = TPM->findAnalysisUsage(P);
if (AnUsage->getPreservesAll())
return;
const AnalysisUsage::VectorType &PreservedSet = AnUsage->getPreservedSet();
for (DenseMap<AnalysisID, Pass*>::iterator I = AvailableAnalysis.begin(),
E = AvailableAnalysis.end(); I != E; ) {
DenseMap<AnalysisID, Pass*>::iterator Info = I++;
if (Info->second->getAsImmutablePass() == nullptr &&
std::find(PreservedSet.begin(), PreservedSet.end(), Info->first) ==
PreservedSet.end()) {
// Remove this analysis
if (PassDebugging >= Details) {
Pass *S = Info->second;
dbgs() << " -- '" << P->getPassName() << "' is not preserving '";
dbgs() << S->getPassName() << "'\n";
}
AvailableAnalysis.erase(Info);
}
}
// Check inherited analysis also. If P is not preserving analysis
// provided by parent manager then remove it here.
for (unsigned Index = 0; Index < PMT_Last; ++Index) {
if (!InheritedAnalysis[Index])
continue;
for (DenseMap<AnalysisID, Pass*>::iterator
I = InheritedAnalysis[Index]->begin(),
E = InheritedAnalysis[Index]->end(); I != E; ) {
DenseMap<AnalysisID, Pass *>::iterator Info = I++;
if (Info->second->getAsImmutablePass() == nullptr &&
std::find(PreservedSet.begin(), PreservedSet.end(), Info->first) ==
PreservedSet.end()) {
// Remove this analysis
if (PassDebugging >= Details) {
Pass *S = Info->second;
dbgs() << " -- '" << P->getPassName() << "' is not preserving '";
dbgs() << S->getPassName() << "'\n";
}
InheritedAnalysis[Index]->erase(Info);
}
}
}
}
/// Remove analysis passes that are not used any longer
void PMDataManager::removeDeadPasses(Pass *P, StringRef Msg,
enum PassDebuggingString DBG_STR) {
SmallVector<Pass *, 12> DeadPasses;
// If this is a on the fly manager then it does not have TPM.
if (!TPM)
return;
TPM->collectLastUses(DeadPasses, P);
if (PassDebugging >= Details && !DeadPasses.empty()) {
dbgs() << " -*- '" << P->getPassName();
dbgs() << "' is the last user of following pass instances.";
dbgs() << " Free these instances\n";
}
for (SmallVectorImpl<Pass *>::iterator I = DeadPasses.begin(),
E = DeadPasses.end(); I != E; ++I)
freePass(*I, Msg, DBG_STR);
}
void PMDataManager::freePass(Pass *P, StringRef Msg,
enum PassDebuggingString DBG_STR) {
dumpPassInfo(P, FREEING_MSG, DBG_STR, Msg);
{
// If the pass crashes releasing memory, remember this.
PassManagerPrettyStackEntry X(P);
TimeRegion PassTimer(getPassTimer(P));
P->releaseMemory();
}
AnalysisID PI = P->getPassID();
if (const PassInfo *PInf = TPM->findAnalysisPassInfo(PI)) {
// Remove the pass itself (if it is not already removed).
AvailableAnalysis.erase(PI);
// Remove all interfaces this pass implements, for which it is also
// listed as the available implementation.
const std::vector<const PassInfo*> &II = PInf->getInterfacesImplemented();
for (unsigned i = 0, e = II.size(); i != e; ++i) {
DenseMap<AnalysisID, Pass*>::iterator Pos =
AvailableAnalysis.find(II[i]->getTypeInfo());
if (Pos != AvailableAnalysis.end() && Pos->second == P)
AvailableAnalysis.erase(Pos);
}
}
}
/// Add pass P into the PassVector. Update
/// AvailableAnalysis appropriately if ProcessAnalysis is true.
void PMDataManager::add(Pass *P, bool ProcessAnalysis) {
std::unique_ptr<Pass> PPtr(P); // HLSL Change - take ownership of P
// This manager is going to manage pass P. Set up analysis resolver
// to connect them.
AnalysisResolver *AR = new AnalysisResolver(*this);
P->setResolver(AR); // HLSL Note: setResolver takes onwership of AR
// If a FunctionPass F is the last user of ModulePass info M
// then the F's manager, not F, records itself as a last user of M.
SmallVector<Pass *, 12> TransferLastUses;
if (!ProcessAnalysis) {
// Add pass
PassVector.push_back(P);
PPtr.release(); // HLSL Change
return;
}
// At the moment, this pass is the last user of all required passes.
SmallVector<Pass *, 12> LastUses;
SmallVector<Pass *, 8> RequiredPasses;
SmallVector<AnalysisID, 8> ReqAnalysisNotAvailable;
unsigned PDepth = this->getDepth();
collectRequiredAnalysis(RequiredPasses,
ReqAnalysisNotAvailable, P);
for (SmallVectorImpl<Pass *>::iterator I = RequiredPasses.begin(),
E = RequiredPasses.end(); I != E; ++I) {
Pass *PRequired = *I;
unsigned RDepth = 0;
assert(PRequired->getResolver() && "Analysis Resolver is not set");
PMDataManager &DM = PRequired->getResolver()->getPMDataManager();
RDepth = DM.getDepth();
if (PDepth == RDepth)
LastUses.push_back(PRequired);
else if (PDepth > RDepth) {
// Let the parent claim responsibility of last use
TransferLastUses.push_back(PRequired);
// Keep track of higher level analysis used by this manager.
HigherLevelAnalysis.push_back(PRequired);
} else
llvm_unreachable("Unable to accommodate Required Pass");
}
// Set P as P's last user until someone starts using P.
// However, if P is a Pass Manager then it does not need
// to record its last user.
if (!P->getAsPMDataManager())
LastUses.push_back(P);
TPM->setLastUser(LastUses, P);
if (!TransferLastUses.empty()) {
Pass *My_PM = getAsPass();
TPM->setLastUser(TransferLastUses, My_PM);
TransferLastUses.clear();
}
// Now, take care of required analyses that are not available.
for (SmallVectorImpl<AnalysisID>::iterator
I = ReqAnalysisNotAvailable.begin(),
E = ReqAnalysisNotAvailable.end() ;I != E; ++I) {
const PassInfo *PI = TPM->findAnalysisPassInfo(*I);
Pass *AnalysisPass = PI->createPass();
this->addLowerLevelRequiredPass(P, AnalysisPass);
}
// Take a note of analysis required and made available by this pass.
// Remove the analysis not preserved by this pass
removeNotPreservedAnalysis(P);
recordAvailableAnalysis(P);
// Add pass
PassVector.push_back(P);
PPtr.release(); // HLSL Change
}
/// Populate RP with analysis pass that are required by
/// pass P and are available. Populate RP_NotAvail with analysis
/// pass that are required by pass P but are not available.
void PMDataManager::collectRequiredAnalysis(SmallVectorImpl<Pass *> &RP,
SmallVectorImpl<AnalysisID> &RP_NotAvail,
Pass *P) {
AnalysisUsage *AnUsage = TPM->findAnalysisUsage(P);
const AnalysisUsage::VectorType &RequiredSet = AnUsage->getRequiredSet();
for (AnalysisUsage::VectorType::const_iterator
I = RequiredSet.begin(), E = RequiredSet.end(); I != E; ++I) {
if (Pass *AnalysisPass = findAnalysisPass(*I, true))
RP.push_back(AnalysisPass);
else
RP_NotAvail.push_back(*I);
}
const AnalysisUsage::VectorType &IDs = AnUsage->getRequiredTransitiveSet();
for (AnalysisUsage::VectorType::const_iterator I = IDs.begin(),
E = IDs.end(); I != E; ++I) {
if (Pass *AnalysisPass = findAnalysisPass(*I, true))
RP.push_back(AnalysisPass);
else
RP_NotAvail.push_back(*I);
}
}
// All Required analyses should be available to the pass as it runs! Here
// we fill in the AnalysisImpls member of the pass so that it can
// successfully use the getAnalysis() method to retrieve the
// implementations it needs.
//
void PMDataManager::initializeAnalysisImpl(Pass *P) {
AnalysisUsage *AnUsage = TPM->findAnalysisUsage(P);
for (AnalysisUsage::VectorType::const_iterator
I = AnUsage->getRequiredSet().begin(),
E = AnUsage->getRequiredSet().end(); I != E; ++I) {
Pass *Impl = findAnalysisPass(*I, true);
if (!Impl)
// This may be analysis pass that is initialized on the fly.
// If that is not the case then it will raise an assert when it is used.
continue;
AnalysisResolver *AR = P->getResolver();
assert(AR && "Analysis Resolver is not set");
AR->addAnalysisImplsPair(*I, Impl);
}
}
/// Find the pass that implements Analysis AID. If desired pass is not found
/// then return NULL.
Pass *PMDataManager::findAnalysisPass(AnalysisID AID, bool SearchParent) {
// Check if AvailableAnalysis map has one entry.
DenseMap<AnalysisID, Pass*>::const_iterator I = AvailableAnalysis.find(AID);
if (I != AvailableAnalysis.end())
return I->second;
// Search Parents through TopLevelManager
if (SearchParent)
return TPM->findAnalysisPass(AID);
return nullptr;
}
// Print list of passes that are last used by P.
void PMDataManager::dumpLastUses(Pass *P, unsigned Offset) const{
SmallVector<Pass *, 12> LUses;
// If this is a on the fly manager then it does not have TPM.
if (!TPM)
return;
TPM->collectLastUses(LUses, P);
for (SmallVectorImpl<Pass *>::iterator I = LUses.begin(),
E = LUses.end(); I != E; ++I) {
dbgs() << "--" << std::string(Offset*2, ' ');
(*I)->dumpPassStructure(0);
}
}
void PMDataManager::dumpPassArguments() const {
for (SmallVectorImpl<Pass *>::const_iterator I = PassVector.begin(),
E = PassVector.end(); I != E; ++I) {
if (PMDataManager *PMD = (*I)->getAsPMDataManager())
PMD->dumpPassArguments();
else
if (const PassInfo *PI =
TPM->findAnalysisPassInfo((*I)->getPassID()))
if (!PI->isAnalysisGroup())
dbgs() << " -" << PI->getPassArgument();
}
}
void PMDataManager::dumpPassInfo(Pass *P, enum PassDebuggingString S1,
enum PassDebuggingString S2,
StringRef Msg) {
if (PassDebugging < Executions)
return;
dbgs() << "[" << sys::TimeValue::now().str() << "] " << (void *)this
<< std::string(getDepth() * 2 + 1, ' ');
switch (S1) {
case EXECUTION_MSG:
dbgs() << "Executing Pass '" << P->getPassName();
break;
case MODIFICATION_MSG:
dbgs() << "Made Modification '" << P->getPassName();
break;
case FREEING_MSG:
dbgs() << " Freeing Pass '" << P->getPassName();
break;
default:
break;
}
switch (S2) {
case ON_BASICBLOCK_MSG:
dbgs() << "' on BasicBlock '" << Msg << "'...\n";
break;
case ON_FUNCTION_MSG:
dbgs() << "' on Function '" << Msg << "'...\n";
break;
case ON_MODULE_MSG:
dbgs() << "' on Module '" << Msg << "'...\n";
break;
case ON_REGION_MSG:
dbgs() << "' on Region '" << Msg << "'...\n";
break;
case ON_LOOP_MSG:
dbgs() << "' on Loop '" << Msg << "'...\n";
break;
case ON_CG_MSG:
dbgs() << "' on Call Graph Nodes '" << Msg << "'...\n";
break;
default:
break;
}
}
void PMDataManager::dumpRequiredSet(const Pass *P) const {
if (PassDebugging < Details)
return;
AnalysisUsage analysisUsage;
P->getAnalysisUsage(analysisUsage);
dumpAnalysisUsage("Required", P, analysisUsage.getRequiredSet());
}
void PMDataManager::dumpPreservedSet(const Pass *P) const {
if (PassDebugging < Details)
return;
AnalysisUsage analysisUsage;
P->getAnalysisUsage(analysisUsage);
dumpAnalysisUsage("Preserved", P, analysisUsage.getPreservedSet());
}
void PMDataManager::dumpAnalysisUsage(StringRef Msg, const Pass *P,
const AnalysisUsage::VectorType &Set) const {
assert(PassDebugging >= Details);
if (Set.empty())
return;
dbgs() << (const void*)P << std::string(getDepth()*2+3, ' ') << Msg << " Analyses:";
for (unsigned i = 0; i != Set.size(); ++i) {
if (i) dbgs() << ',';
const PassInfo *PInf = TPM->findAnalysisPassInfo(Set[i]);
if (!PInf) {
// Some preserved passes, such as AliasAnalysis, may not be initialized by
// all drivers.
dbgs() << " Uninitialized Pass";
continue;
}
dbgs() << ' ' << PInf->getPassName();
}
dbgs() << '\n';
}
/// Add RequiredPass into list of lower level passes required by pass P.
/// RequiredPass is run on the fly by Pass Manager when P requests it
/// through getAnalysis interface.
/// This should be handled by specific pass manager.
void PMDataManager::addLowerLevelRequiredPass(Pass *P, Pass *RequiredPass) {
if (TPM) {
TPM->dumpArguments();
TPM->dumpPasses();
}
// Module Level pass may required Function Level analysis info
// (e.g. dominator info). Pass manager uses on the fly function pass manager
// to provide this on demand. In that case, in Pass manager terminology,
// module level pass is requiring lower level analysis info managed by
// lower level pass manager.
// When Pass manager is not able to order required analysis info, Pass manager
// checks whether any lower level manager will be able to provide this
// analysis info on demand or not.
#ifndef NDEBUG
dbgs() << "Unable to schedule '" << RequiredPass->getPassName();
dbgs() << "' required by '" << P->getPassName() << "'\n";
#endif
llvm_unreachable("Unable to schedule pass");
}
Pass *PMDataManager::getOnTheFlyPass(Pass *P, AnalysisID PI, Function &F) {
llvm_unreachable("Unable to find on the fly pass");
}
// Destructor
PMDataManager::~PMDataManager() {
for (SmallVectorImpl<Pass *>::iterator I = PassVector.begin(),
E = PassVector.end(); I != E; ++I)
delete *I;
}
//===----------------------------------------------------------------------===//
// NOTE: Is this the right place to define this method ?
// getAnalysisIfAvailable - Return analysis result or null if it doesn't exist.
Pass *AnalysisResolver::getAnalysisIfAvailable(AnalysisID ID, bool dir) const {
return PM.findAnalysisPass(ID, dir);
}
Pass *AnalysisResolver::findImplPass(Pass *P, AnalysisID AnalysisPI,
Function &F) {
return PM.getOnTheFlyPass(P, AnalysisPI, F);
}
//===----------------------------------------------------------------------===//
// BBPassManager implementation
/// Execute all of the passes scheduled for execution by invoking
/// runOnBasicBlock method. Keep track of whether any of the passes modifies
/// the function, and if so, return true.
bool BBPassManager::runOnFunction(Function &F) {
if (F.isDeclaration())
return false;
bool Changed = doInitialization(F);
for (Function::iterator I = F.begin(), E = F.end(); I != E; ++I)
for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
BasicBlockPass *BP = getContainedPass(Index);
bool LocalChanged = false;
dumpPassInfo(BP, EXECUTION_MSG, ON_BASICBLOCK_MSG, I->getName());
dumpRequiredSet(BP);
initializeAnalysisImpl(BP);
{
// If the pass crashes, remember this.
PassManagerPrettyStackEntry X(BP, *I);
TimeRegion PassTimer(getPassTimer(BP));
LocalChanged |= BP->runOnBasicBlock(*I);
}
Changed |= LocalChanged;
if (LocalChanged)
dumpPassInfo(BP, MODIFICATION_MSG, ON_BASICBLOCK_MSG,
I->getName());
dumpPreservedSet(BP);
verifyPreservedAnalysis(BP);
removeNotPreservedAnalysis(BP);
recordAvailableAnalysis(BP);
removeDeadPasses(BP, I->getName(), ON_BASICBLOCK_MSG);
}
return doFinalization(F) || Changed;
}
// Implement doInitialization and doFinalization
bool BBPassManager::doInitialization(Module &M) {
bool Changed = false;
for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index)
Changed |= getContainedPass(Index)->doInitialization(M);
return Changed;
}
bool BBPassManager::doFinalization(Module &M) {
bool Changed = false;
for (int Index = getNumContainedPasses() - 1; Index >= 0; --Index)
Changed |= getContainedPass(Index)->doFinalization(M);
return Changed;
}
bool BBPassManager::doInitialization(Function &F) {
bool Changed = false;
for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
BasicBlockPass *BP = getContainedPass(Index);
Changed |= BP->doInitialization(F);
}
return Changed;
}
bool BBPassManager::doFinalization(Function &F) {
bool Changed = false;
for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
BasicBlockPass *BP = getContainedPass(Index);
Changed |= BP->doFinalization(F);
}
return Changed;
}
//===----------------------------------------------------------------------===//
// FunctionPassManager implementation
/// Create new Function pass manager
FunctionPassManager::FunctionPassManager(Module *m) : M(m) {
FPM = new FunctionPassManagerImpl();
// FPM is the top level manager.
FPM->setTopLevelManager(FPM);
AnalysisResolver *AR = new (std::nothrow)AnalysisResolver(*FPM); // HLSL Change: nothrow and recover
if (!AR) {
delete FPM;
throw std::bad_alloc();
}
FPM->setResolver(AR);
}
FunctionPassManager::~FunctionPassManager() {
delete FPM;
}
void FunctionPassManager::add(Pass *P) {
// HLSL Change Starts
FPM->HLSLPrintBeforeAll = this->HLSLPrintBeforeAll;
FPM->HLSLPrintBefore = this->HLSLPrintBefore;
FPM->HLSLPrintAfterAll = this->HLSLPrintAfterAll;
FPM->HLSLPrintAfter = this->HLSLPrintAfter;
std::unique_ptr<Pass> PPtr(P); // take ownership of P, even on failure paths
if (TrackPassOS) {
P->dumpConfig(*TrackPassOS);
(*TrackPassOS) << '\n';
}
PPtr.release();
// HLSL Change Ends
FPM->add(P);
}
/// run - Execute all of the passes scheduled for execution. Keep
/// track of whether any of the passes modifies the function, and if
/// so, return true.
///
bool FunctionPassManager::run(Function &F) {
if (std::error_code EC = F.materialize())
report_fatal_error("Error reading bitcode file: " + EC.message());
return FPM->run(F);
}
/// doInitialization - Run all of the initializers for the function passes.
///
bool FunctionPassManager::doInitialization() {
return FPM->doInitialization(*M);
}
/// doFinalization - Run all of the finalizers for the function passes.
///
bool FunctionPassManager::doFinalization() {
return FPM->doFinalization(*M);
}
//===----------------------------------------------------------------------===//
// FunctionPassManagerImpl implementation
//
bool FunctionPassManagerImpl::doInitialization(Module &M) {
bool Changed = false;
dumpArguments();
dumpPasses();
for (ImmutablePass *ImPass : getImmutablePasses())
Changed |= ImPass->doInitialization(M);
for (unsigned Index = 0; Index < getNumContainedManagers(); ++Index)
Changed |= getContainedManager(Index)->doInitialization(M);
return Changed;
}
bool FunctionPassManagerImpl::doFinalization(Module &M) {
bool Changed = false;
for (int Index = getNumContainedManagers() - 1; Index >= 0; --Index)
Changed |= getContainedManager(Index)->doFinalization(M);
for (ImmutablePass *ImPass : getImmutablePasses())
Changed |= ImPass->doFinalization(M);
return Changed;
}
/// cleanup - After running all passes, clean up pass manager cache.
void FPPassManager::cleanup() {
for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
FunctionPass *FP = getContainedPass(Index);
AnalysisResolver *AR = FP->getResolver();
assert(AR && "Analysis Resolver is not set");
AR->clearAnalysisImpls();
}
}
void FunctionPassManagerImpl::releaseMemoryOnTheFly() {
if (!wasRun)
return;
for (unsigned Index = 0; Index < getNumContainedManagers(); ++Index) {
FPPassManager *FPPM = getContainedManager(Index);
for (unsigned Index = 0; Index < FPPM->getNumContainedPasses(); ++Index) {
FPPM->getContainedPass(Index)->releaseMemory();
}
}
wasRun = false;
}
// Execute all the passes managed by this top level manager.
// Return true if any function is modified by a pass.
bool FunctionPassManagerImpl::run(Function &F) {
bool Changed = false;
TimingInfo::createTheTimeInfo();
initializeAllAnalysisInfo();
for (unsigned Index = 0; Index < getNumContainedManagers(); ++Index) {
Changed |= getContainedManager(Index)->runOnFunction(F);
F.getContext().yield();
}
for (unsigned Index = 0; Index < getNumContainedManagers(); ++Index)
getContainedManager(Index)->cleanup();
wasRun = true;
return Changed;
}
//===----------------------------------------------------------------------===//
// FPPassManager implementation
char FPPassManager::ID = 0;
/// Print passes managed by this manager
void FPPassManager::dumpPassStructure(unsigned Offset) {
dbgs().indent(Offset*2) << "FunctionPass Manager\n";
for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
FunctionPass *FP = getContainedPass(Index);
FP->dumpPassStructure(Offset + 1);
dumpLastUses(FP, Offset+1);
}
}
/// Execute all of the passes scheduled for execution by invoking
/// runOnFunction method. Keep track of whether any of the passes modifies
/// the function, and if so, return true.
bool FPPassManager::runOnFunction(Function &F) {
if (F.isDeclaration())
return false;
bool Changed = false;
// Collect inherited analysis from Module level pass manager.
populateInheritedAnalysis(TPM->activeStack);
// HLSL Change Begin - Support hierarchial time tracing.
llvm::TimeTraceScope FunctionScope("OptFunction", F.getName());
// HLSL Change End
for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
FunctionPass *FP = getContainedPass(Index);
bool LocalChanged = false;
// HLSL Change Begin - Support hierarchial time tracing.
llvm::TimeTraceScope PassScope("RunFunctionPass", FP->getPassName());
// HLSL Change End - Support hierarchial time tracing.
dumpPassInfo(FP, EXECUTION_MSG, ON_FUNCTION_MSG, F.getName());
dumpRequiredSet(FP);
initializeAnalysisImpl(FP);
{
PassManagerPrettyStackEntry X(FP, F);
TimeRegion PassTimer(getPassTimer(FP));
LocalChanged |= FP->runOnFunction(F);
}
Changed |= LocalChanged;
if (LocalChanged)
dumpPassInfo(FP, MODIFICATION_MSG, ON_FUNCTION_MSG, F.getName());
dumpPreservedSet(FP);
verifyPreservedAnalysis(FP);
removeNotPreservedAnalysis(FP);
recordAvailableAnalysis(FP);
removeDeadPasses(FP, F.getName(), ON_FUNCTION_MSG);
}
return Changed;
}
bool FPPassManager::runOnModule(Module &M) {
bool Changed = false;
llvm::TimeTraceScope TimeScope("OptModule", M.getName());
for (Function &F : M)
Changed |= runOnFunction(F);
return Changed;
}
bool FPPassManager::doInitialization(Module &M) {
bool Changed = false;
for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index)
Changed |= getContainedPass(Index)->doInitialization(M);
return Changed;
}
bool FPPassManager::doFinalization(Module &M) {
bool Changed = false;
for (int Index = getNumContainedPasses() - 1; Index >= 0; --Index)
Changed |= getContainedPass(Index)->doFinalization(M);
return Changed;
}
//===----------------------------------------------------------------------===//
// MPPassManager implementation
/// Execute all of the passes scheduled for execution by invoking
/// runOnModule method. Keep track of whether any of the passes modifies
/// the module, and if so, return true.
bool
MPPassManager::runOnModule(Module &M) {
llvm::TimeTraceScope TimeScope("OptModule", M.getName());
bool Changed = false;
// Initialize on-the-fly passes
for (auto &OnTheFlyManager : OnTheFlyManagers) {
FunctionPassManagerImpl *FPP = OnTheFlyManager.second;
Changed |= FPP->doInitialization(M);
}
// Initialize module passes
for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index)
Changed |= getContainedPass(Index)->doInitialization(M);
for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
ModulePass *MP = getContainedPass(Index);
bool LocalChanged = false;
llvm::TimeTraceScope PassScope("RunModulePass", MP->getPassName());
dumpPassInfo(MP, EXECUTION_MSG, ON_MODULE_MSG, M.getModuleIdentifier());
dumpRequiredSet(MP);
initializeAnalysisImpl(MP);
{
PassManagerPrettyStackEntry X(MP, M);
TimeRegion PassTimer(getPassTimer(MP));
LocalChanged |= MP->runOnModule(M);
}
Changed |= LocalChanged;
if (LocalChanged)
dumpPassInfo(MP, MODIFICATION_MSG, ON_MODULE_MSG,
M.getModuleIdentifier());
dumpPreservedSet(MP);
verifyPreservedAnalysis(MP);
removeNotPreservedAnalysis(MP);
recordAvailableAnalysis(MP);
removeDeadPasses(MP, M.getModuleIdentifier(), ON_MODULE_MSG);
}
// Finalize module passes
for (int Index = getNumContainedPasses() - 1; Index >= 0; --Index)
Changed |= getContainedPass(Index)->doFinalization(M);
// Finalize on-the-fly passes
for (auto &OnTheFlyManager : OnTheFlyManagers) {
FunctionPassManagerImpl *FPP = OnTheFlyManager.second;
// We don't know when is the last time an on-the-fly pass is run,
// so we need to releaseMemory / finalize here
FPP->releaseMemoryOnTheFly();
Changed |= FPP->doFinalization(M);
}
return Changed;
}
/// Add RequiredPass into list of lower level passes required by pass P.
/// RequiredPass is run on the fly by Pass Manager when P requests it
/// through getAnalysis interface.
void MPPassManager::addLowerLevelRequiredPass(Pass *P, Pass *RequiredPass) {
assert(P->getPotentialPassManagerType() == PMT_ModulePassManager &&
"Unable to handle Pass that requires lower level Analysis pass");
assert((P->getPotentialPassManagerType() <
RequiredPass->getPotentialPassManagerType()) &&
"Unable to handle Pass that requires lower level Analysis pass");
if (!RequiredPass)
return;
FunctionPassManagerImpl *FPP = OnTheFlyManagers[P];
if (!FPP) {
FPP = new FunctionPassManagerImpl();
// FPP is the top level manager.
FPP->setTopLevelManager(FPP);
OnTheFlyManagers[P] = FPP;
}
const PassInfo *RequiredPassPI =
TPM->findAnalysisPassInfo(RequiredPass->getPassID());
Pass *FoundPass = nullptr;
if (RequiredPassPI && RequiredPassPI->isAnalysis()) {
FoundPass =
((PMTopLevelManager*)FPP)->findAnalysisPass(RequiredPass->getPassID());
}
if (!FoundPass) {
FoundPass = RequiredPass;
// This should be guaranteed to add RequiredPass to the passmanager given
// that we checked for an available analysis above.
FPP->add(RequiredPass);
}
// Register P as the last user of FoundPass or RequiredPass.
SmallVector<Pass *, 1> LU;
LU.push_back(FoundPass);
FPP->setLastUser(LU, P);
}
/// Return function pass corresponding to PassInfo PI, that is
/// required by module pass MP. Instantiate analysis pass, by using
/// its runOnFunction() for function F.
Pass* MPPassManager::getOnTheFlyPass(Pass *MP, AnalysisID PI, Function &F){
FunctionPassManagerImpl *FPP = OnTheFlyManagers[MP];
assert(FPP && "Unable to find on the fly pass");
FPP->releaseMemoryOnTheFly();
FPP->run(F);
return ((PMTopLevelManager*)FPP)->findAnalysisPass(PI);
}
//===----------------------------------------------------------------------===//
// PassManagerImpl implementation
//
/// run - Execute all of the passes scheduled for execution. Keep track of
/// whether any of the passes modifies the module, and if so, return true.
bool PassManagerImpl::run(Module &M) {
bool Changed = false;
TimingInfo::createTheTimeInfo();
dumpArguments();
dumpPasses();
for (ImmutablePass *ImPass : getImmutablePasses())
Changed |= ImPass->doInitialization(M);
initializeAllAnalysisInfo();
for (unsigned Index = 0; Index < getNumContainedManagers(); ++Index) {
Changed |= getContainedManager(Index)->runOnModule(M);
M.getContext().yield();
}
for (ImmutablePass *ImPass : getImmutablePasses())
Changed |= ImPass->doFinalization(M);
return Changed;
}
//===----------------------------------------------------------------------===//
// PassManager implementation
/// Create new pass manager
PassManager::PassManager() {
PM = new PassManagerImpl();
// PM is the top level manager
PM->setTopLevelManager(PM);
}
PassManager::~PassManager() {
delete PM;
}
void PassManager::add(Pass *P) {
// HLSL Change Starts
PM->HLSLPrintBeforeAll = this->HLSLPrintBeforeAll;
PM->HLSLPrintBefore = this->HLSLPrintBefore;
PM->HLSLPrintAfterAll = this->HLSLPrintAfterAll;
PM->HLSLPrintAfter = this->HLSLPrintAfter;
std::unique_ptr<Pass> PPtr(P); // take ownership of P, even on failure paths
if (TrackPassOS) {
P->dumpConfig(*TrackPassOS);
(*TrackPassOS) << '\n';
}
PPtr.release();
// HLSL Change Ends
PM->add(P);
}
/// run - Execute all of the passes scheduled for execution. Keep track of
/// whether any of the passes modifies the module, and if so, return true.
bool PassManager::run(Module &M) {
return PM->run(M);
}
//===----------------------------------------------------------------------===//
// TimingInfo implementation
bool llvm::TimePassesIsEnabled = false;
#if 0 // HLSL Change Starts - option pending
static cl::opt<bool,true>
EnableTiming("time-passes", cl::location(TimePassesIsEnabled),
cl::desc("Time each pass, printing elapsed time for each on exit"));
#endif
// createTheTimeInfo - This method either initializes the TheTimeInfo pointer to
// a non-null value (if the -time-passes option is enabled) or it leaves it
// null. It may be called multiple times.
void TimingInfo::createTheTimeInfo() {
if (!TimePassesIsEnabled || TheTimeInfo) return;
// Constructed the first time this is called, iff -time-passes is enabled.
// This guarantees that the object will be constructed before static globals,
// thus it will be destroyed before them.
static ManagedStatic<TimingInfo> TTI;
TheTimeInfo = &*TTI;
}
/// If TimingInfo is enabled then start pass timer.
Timer *llvm::getPassTimer(Pass *P) {
if (TheTimeInfo)
return TheTimeInfo->getPassTimer(P);
return nullptr;
}
//===----------------------------------------------------------------------===//
// PMStack implementation
//
// Pop Pass Manager from the stack and clear its analysis info.
void PMStack::pop() {
PMDataManager *Top = this->top();
Top->initializeAnalysisInfo();
S.pop_back();
}
// Push PM on the stack and set its top level manager.
void PMStack::push(PMDataManager *PM) {
assert(PM && "Unable to push. Pass Manager expected");
assert(PM->getDepth()==0 && "Pass Manager depth set too early");
if (!this->empty()) {
assert(PM->getPassManagerType() > this->top()->getPassManagerType()
&& "pushing bad pass manager to PMStack");
PMTopLevelManager *TPM = this->top()->getTopLevelManager();
assert(TPM && "Unable to find top level manager");
TPM->addIndirectPassManager(PM);
PM->setTopLevelManager(TPM);
PM->setDepth(this->top()->getDepth()+1);
} else {
assert((PM->getPassManagerType() == PMT_ModulePassManager
|| PM->getPassManagerType() == PMT_FunctionPassManager)
&& "pushing bad pass manager to PMStack");
PM->setDepth(1);
}
S.push_back(PM);
}
// Dump content of the pass manager stack.
void PMStack::dump() const {
for (PMDataManager *Manager : S)
dbgs() << Manager->getAsPass()->getPassName() << ' ';
if (!S.empty())
dbgs() << '\n';
}
/// Find appropriate Module Pass Manager in the PM Stack and
/// add self into that manager.
void ModulePass::assignPassManager(PMStack &PMS,
PassManagerType PreferredType) {
// Find Module Pass Manager
while (!PMS.empty()) {
PassManagerType TopPMType = PMS.top()->getPassManagerType();
if (TopPMType == PreferredType)
break; // We found desired pass manager
else if (TopPMType > PMT_ModulePassManager)
PMS.pop(); // Pop children pass managers
else
break;
}
assert(!PMS.empty() && "Unable to find appropriate Pass Manager");
PMS.top()->add(this);
}
/// Find appropriate Function Pass Manager or Call Graph Pass Manager
/// in the PM Stack and add self into that manager.
void FunctionPass::assignPassManager(PMStack &PMS,
PassManagerType PreferredType) {
std::unique_ptr<FunctionPass> thisPtr(this); // HLSL Change
// Find Function Pass Manager
while (!PMS.empty()) {
if (PMS.top()->getPassManagerType() > PMT_FunctionPassManager)
PMS.pop();
else
break;
}
// Create new Function Pass Manager if needed.
FPPassManager *FPP;
if (PMS.top()->getPassManagerType() == PMT_FunctionPassManager) {
FPP = (FPPassManager *)PMS.top();
} else {
assert(!PMS.empty() && "Unable to create Function Pass Manager");
PMDataManager *PMD = PMS.top();
// [1] Create new Function Pass Manager
FPP = new FPPassManager();
std::unique_ptr<FPPassManager> NewFPP(FPP); // HLSL Change
FPP->populateInheritedAnalysis(PMS);
// [2] Set up new manager's top level manager
PMTopLevelManager *TPM = PMD->getTopLevelManager();
TPM->addIndirectPassManager(FPP);
// [3] Assign manager to manage this new manager. This may create
// and push new managers into PMS
NewFPP.release(); // HLSL Change: assignPassManager transfers ownership of 'this'...
FPP->assignPassManager(PMS, PMD->getPassManagerType());
// [4] Push new manager into PMS
PMS.push(FPP);
}
// Assign FPP as the manager of this pass.
thisPtr.release();
FPP->add(this);
}
/// Find appropriate Basic Pass Manager or Call Graph Pass Manager
/// in the PM Stack and add self into that manager.
void BasicBlockPass::assignPassManager(PMStack &PMS,
PassManagerType PreferredType) {
BBPassManager *BBP;
// Basic Pass Manager is a leaf pass manager. It does not handle
// any other pass manager.
if (!PMS.empty() &&
PMS.top()->getPassManagerType() == PMT_BasicBlockPassManager) {
BBP = (BBPassManager *)PMS.top();
} else {
// If leaf manager is not Basic Block Pass manager then create new
// basic Block Pass manager.
assert(!PMS.empty() && "Unable to create BasicBlock Pass Manager");
PMDataManager *PMD = PMS.top();
// [1] Create new Basic Block Manager
BBP = new BBPassManager();
// [2] Set up new manager's top level manager
// Basic Block Pass Manager does not live by itself
PMTopLevelManager *TPM = PMD->getTopLevelManager();
TPM->addIndirectPassManager(BBP);
// [3] Assign manager to manage this new manager. This may create
// and push new managers into PMS
BBP->assignPassManager(PMS, PreferredType);
// [4] Push new manager into PMS
PMS.push(BBP);
}
// Assign BBP as the manager of this pass.
BBP->add(this);
}
PassManagerBase::~PassManagerBase() {}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/InlineAsm.cpp | //===-- InlineAsm.cpp - Implement the InlineAsm class ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the InlineAsm class.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/InlineAsm.h"
#include "ConstantsContext.h"
#include "LLVMContextImpl.h"
#include "llvm/IR/DerivedTypes.h"
#include <algorithm>
#include <cctype>
using namespace llvm;
// Implement the first virtual method in this class in this file so the
// InlineAsm vtable is emitted here.
InlineAsm::~InlineAsm() {
}
InlineAsm *InlineAsm::get(FunctionType *Ty, StringRef AsmString,
StringRef Constraints, bool hasSideEffects,
bool isAlignStack, AsmDialect asmDialect) {
InlineAsmKeyType Key(AsmString, Constraints, hasSideEffects, isAlignStack,
asmDialect);
LLVMContextImpl *pImpl = Ty->getContext().pImpl;
return pImpl->InlineAsms.getOrCreate(PointerType::getUnqual(Ty), Key);
}
InlineAsm::InlineAsm(PointerType *Ty, const std::string &asmString,
const std::string &constraints, bool hasSideEffects,
bool isAlignStack, AsmDialect asmDialect)
: Value(Ty, Value::InlineAsmVal),
AsmString(asmString), Constraints(constraints),
HasSideEffects(hasSideEffects), IsAlignStack(isAlignStack),
Dialect(asmDialect) {
// Do various checks on the constraint string and type.
assert(Verify(getFunctionType(), constraints) &&
"Function type not legal for constraints!");
}
void InlineAsm::destroyConstant() {
getType()->getContext().pImpl->InlineAsms.remove(this);
delete this;
}
FunctionType *InlineAsm::getFunctionType() const {
return cast<FunctionType>(getType()->getElementType());
}
///Default constructor.
InlineAsm::ConstraintInfo::ConstraintInfo() :
Type(isInput), isEarlyClobber(false),
MatchingInput(-1), isCommutative(false),
isIndirect(false), isMultipleAlternative(false),
currentAlternativeIndex(0) {
}
/// Parse - Analyze the specified string (e.g. "==&{eax}") and fill in the
/// fields in this structure. If the constraint string is not understood,
/// return true, otherwise return false.
bool InlineAsm::ConstraintInfo::Parse(StringRef Str,
InlineAsm::ConstraintInfoVector &ConstraintsSoFar) {
StringRef::iterator I = Str.begin(), E = Str.end();
unsigned multipleAlternativeCount = Str.count('|') + 1;
unsigned multipleAlternativeIndex = 0;
ConstraintCodeVector *pCodes = &Codes;
// Initialize
isMultipleAlternative = multipleAlternativeCount > 1;
if (isMultipleAlternative) {
multipleAlternatives.resize(multipleAlternativeCount);
pCodes = &multipleAlternatives[0].Codes;
}
Type = isInput;
isEarlyClobber = false;
MatchingInput = -1;
isCommutative = false;
isIndirect = false;
currentAlternativeIndex = 0;
// Parse prefixes.
if (*I == '~') {
Type = isClobber;
++I;
// '{' must immediately follow '~'.
if (I != E && *I != '{')
return true;
} else if (*I == '=') {
++I;
Type = isOutput;
}
if (*I == '*') {
isIndirect = true;
++I;
}
if (I == E) return true; // Just a prefix, like "==" or "~".
// Parse the modifiers.
bool DoneWithModifiers = false;
while (!DoneWithModifiers) {
switch (*I) {
default:
DoneWithModifiers = true;
break;
case '&': // Early clobber.
if (Type != isOutput || // Cannot early clobber anything but output.
isEarlyClobber) // Reject &&&&&&
return true;
isEarlyClobber = true;
break;
case '%': // Commutative.
if (Type == isClobber || // Cannot commute clobbers.
isCommutative) // Reject %%%%%
return true;
isCommutative = true;
break;
case '#': // Comment.
case '*': // Register preferencing.
return true; // Not supported.
}
if (!DoneWithModifiers) {
++I;
if (I == E) return true; // Just prefixes and modifiers!
}
}
// Parse the various constraints.
while (I != E) {
if (*I == '{') { // Physical register reference.
// Find the end of the register name.
StringRef::iterator ConstraintEnd = std::find(I+1, E, '}');
if (ConstraintEnd == E) return true; // "{foo"
pCodes->push_back(std::string(I, ConstraintEnd+1));
I = ConstraintEnd+1;
} else if (isdigit(static_cast<unsigned char>(*I))) { // Matching Constraint
// Maximal munch numbers.
StringRef::iterator NumStart = I;
while (I != E && isdigit(static_cast<unsigned char>(*I)))
++I;
pCodes->push_back(std::string(NumStart, I));
unsigned N = atoi(pCodes->back().c_str());
// Check that this is a valid matching constraint!
if (N >= ConstraintsSoFar.size() || ConstraintsSoFar[N].Type != isOutput||
Type != isInput)
return true; // Invalid constraint number.
// If Operand N already has a matching input, reject this. An output
// can't be constrained to the same value as multiple inputs.
if (isMultipleAlternative) {
InlineAsm::SubConstraintInfo &scInfo =
ConstraintsSoFar[N].multipleAlternatives[multipleAlternativeIndex];
if (scInfo.MatchingInput != -1)
return true;
// Note that operand #n has a matching input.
scInfo.MatchingInput = ConstraintsSoFar.size();
} else {
if (ConstraintsSoFar[N].hasMatchingInput() &&
(size_t)ConstraintsSoFar[N].MatchingInput !=
ConstraintsSoFar.size())
return true;
// Note that operand #n has a matching input.
ConstraintsSoFar[N].MatchingInput = ConstraintsSoFar.size();
}
} else if (*I == '|') {
multipleAlternativeIndex++;
pCodes = &multipleAlternatives[multipleAlternativeIndex].Codes;
++I;
} else if (*I == '^') {
// Multi-letter constraint
// FIXME: For now assuming these are 2-character constraints.
pCodes->push_back(std::string(I+1, I+3));
I += 3;
} else {
// Single letter constraint.
pCodes->push_back(std::string(I, I+1));
++I;
}
}
return false;
}
/// selectAlternative - Point this constraint to the alternative constraint
/// indicated by the index.
void InlineAsm::ConstraintInfo::selectAlternative(unsigned index) {
if (index < multipleAlternatives.size()) {
currentAlternativeIndex = index;
InlineAsm::SubConstraintInfo &scInfo =
multipleAlternatives[currentAlternativeIndex];
MatchingInput = scInfo.MatchingInput;
Codes = scInfo.Codes;
}
}
InlineAsm::ConstraintInfoVector
InlineAsm::ParseConstraints(StringRef Constraints) {
ConstraintInfoVector Result;
// Scan the constraints string.
for (StringRef::iterator I = Constraints.begin(),
E = Constraints.end(); I != E; ) {
ConstraintInfo Info;
// Find the end of this constraint.
StringRef::iterator ConstraintEnd = std::find(I, E, ',');
if (ConstraintEnd == I || // Empty constraint like ",,"
Info.Parse(StringRef(I, ConstraintEnd-I), Result)) {
Result.clear(); // Erroneous constraint?
break;
}
Result.push_back(Info);
// ConstraintEnd may be either the next comma or the end of the string. In
// the former case, we skip the comma.
I = ConstraintEnd;
if (I != E) {
++I;
if (I == E) {
Result.clear();
break;
} // don't allow "xyz,"
}
}
return Result;
}
/// Verify - Verify that the specified constraint string is reasonable for the
/// specified function type, and otherwise validate the constraint string.
bool InlineAsm::Verify(FunctionType *Ty, StringRef ConstStr) {
if (Ty->isVarArg()) return false;
ConstraintInfoVector Constraints = ParseConstraints(ConstStr);
// Error parsing constraints.
if (Constraints.empty() && !ConstStr.empty()) return false;
unsigned NumOutputs = 0, NumInputs = 0, NumClobbers = 0;
unsigned NumIndirect = 0;
for (unsigned i = 0, e = Constraints.size(); i != e; ++i) {
switch (Constraints[i].Type) {
case InlineAsm::isOutput:
if ((NumInputs-NumIndirect) != 0 || NumClobbers != 0)
return false; // outputs before inputs and clobbers.
if (!Constraints[i].isIndirect) {
++NumOutputs;
break;
}
++NumIndirect;
// FALLTHROUGH for Indirect Outputs.
LLVM_FALLTHROUGH; // HLSL Change
case InlineAsm::isInput:
if (NumClobbers) return false; // inputs before clobbers.
++NumInputs;
break;
case InlineAsm::isClobber:
++NumClobbers;
break;
}
}
switch (NumOutputs) {
case 0:
if (!Ty->getReturnType()->isVoidTy()) return false;
break;
case 1:
if (Ty->getReturnType()->isStructTy()) return false;
break;
default:
StructType *STy = dyn_cast<StructType>(Ty->getReturnType());
if (!STy || STy->getNumElements() != NumOutputs)
return false;
break;
}
if (Ty->getNumParams() != NumInputs) return false;
return true;
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/GVMaterializer.cpp | //===-- GVMaterializer.cpp - Base implementation for GV materializers -----===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Minimal implementation of the abstract interface for materializing
// GlobalValues.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/GVMaterializer.h"
using namespace llvm;
GVMaterializer::~GVMaterializer() {}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/Verifier.cpp | //===-- Verifier.cpp - Implement the Module Verifier -----------------------==//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the function verifier interface, that can be used for some
// sanity checking of input to the system.
//
// Note that this does not provide full `Java style' security and verifications,
// instead it just tries to ensure that code is well-formed.
//
// * Both of a binary operator's parameters are of the same type
// * Verify that the indices of mem access instructions match other operands
// * Verify that arithmetic and other things are only performed on first-class
// types. Verify that shifts & logicals only happen on integrals f.e.
// * All of the constants in a switch statement are of the correct type
// * The code is in valid SSA form
// * It should be illegal to put a label into any other type (like a structure)
// or to return one. [except constant arrays!]
// * Only phi nodes can be self referential: 'add i32 %0, %0 ; <int>:0' is bad
// * PHI nodes must have an entry for each predecessor, with no extras.
// * PHI nodes must be the first thing in a basic block, all grouped together
// * PHI nodes must have at least one entry
// * All basic blocks should only end with terminator insts, not contain them
// * The entry node to a function must not have predecessors
// * All Instructions must be embedded into a basic block
// * Functions cannot take a void-typed parameter
// * Verify that a function's argument list agrees with it's declared type.
// * It is illegal to specify a name for a void value.
// * It is illegal to have a internal global value with no initializer
// * It is illegal to have a ret instruction that returns a value that does not
// agree with the function return value type.
// * Function call argument types match the function prototype
// * A landing pad is defined by a landingpad instruction, and can be jumped to
// only by the unwind edge of an invoke instruction.
// * A landingpad instruction must be the first non-PHI instruction in the
// block.
// * All landingpad instructions must use the same personality function with
// the same function.
// * All other things that are tested by asserts spread about the code...
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/Verifier.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/ConstantRange.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/InlineAsm.h"
#include "llvm/IR/InstIterator.h"
#include "llvm/IR/InstVisitor.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/PassManager.h"
#include "llvm/IR/Statepoint.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <cstdarg>
using namespace llvm;
#if 0 // HLSL Change Starts - option pending
static cl::opt<bool> VerifyDebugInfo("verify-debug-info", cl::init(true));
#endif // HLSL Change Ends
namespace {
struct VerifierSupport {
raw_ostream &OS;
const Module *M;
/// \brief Track the brokenness of the module while recursively visiting.
bool Broken;
explicit VerifierSupport(raw_ostream &OS)
: OS(OS), M(nullptr), Broken(false) {}
private:
void Write(const Value *V) {
if (!V)
return;
if (isa<Instruction>(V)) {
OS << *V << '\n';
} else {
V->printAsOperand(OS, true, M);
OS << '\n';
}
}
void Write(ImmutableCallSite CS) {
Write(CS.getInstruction());
}
void Write(const Metadata *MD) {
if (!MD)
return;
MD->print(OS, M);
OS << '\n';
}
template <class T> void Write(const MDTupleTypedArrayWrapper<T> &MD) {
Write(MD.get());
}
void Write(const NamedMDNode *NMD) {
if (!NMD)
return;
NMD->print(OS);
OS << '\n';
}
void Write(Type *T) {
if (!T)
return;
OS << ' ' << *T;
}
void Write(const Comdat *C) {
if (!C)
return;
OS << *C;
}
template <typename T1, typename... Ts>
void WriteTs(const T1 &V1, const Ts &... Vs) {
Write(V1);
WriteTs(Vs...);
}
template <typename... Ts> void WriteTs() {}
public:
/// \brief A check failed, so printout out the condition and the message.
///
/// This provides a nice place to put a breakpoint if you want to see why
/// something is not correct.
void CheckFailed(const Twine &Message) {
OS << Message << '\n';
Broken = true;
}
/// \brief A check failed (with values to print).
///
/// This calls the Message-only version so that the above is easier to set a
/// breakpoint on.
template <typename T1, typename... Ts>
void CheckFailed(const Twine &Message, const T1 &V1, const Ts &... Vs) {
CheckFailed(Message);
WriteTs(V1, Vs...);
}
};
class Verifier : public InstVisitor<Verifier>, VerifierSupport {
friend class InstVisitor<Verifier>;
LLVMContext *Context;
DominatorTree DT;
/// \brief When verifying a basic block, keep track of all of the
/// instructions we have seen so far.
///
/// This allows us to do efficient dominance checks for the case when an
/// instruction has an operand that is an instruction in the same block.
SmallPtrSet<Instruction *, 16> InstsInThisBlock;
/// \brief Keep track of the metadata nodes that have been checked already.
SmallPtrSet<const Metadata *, 32> MDNodes;
/// \brief Track unresolved string-based type references.
SmallDenseMap<const MDString *, const MDNode *, 32> UnresolvedTypeRefs;
/// \brief Whether we've seen a call to @llvm.localescape in this function
/// already.
bool SawFrameEscape;
/// Stores the count of how many objects were passed to llvm.localescape for a
/// given function and the largest index passed to llvm.localrecover.
DenseMap<Function *, std::pair<unsigned, unsigned>> FrameEscapeInfo;
public:
explicit Verifier(raw_ostream &OS)
: VerifierSupport(OS), Context(nullptr), SawFrameEscape(false) {}
bool verify(const Function &F) {
M = F.getParent();
Context = &M->getContext();
// First ensure the function is well-enough formed to compute dominance
// information.
if (F.empty()) {
OS << "Function '" << F.getName()
<< "' does not contain an entry block!\n";
return false;
}
for (Function::const_iterator I = F.begin(), E = F.end(); I != E; ++I) {
if (I->empty() || !I->back().isTerminator()) {
OS << "Basic Block in function '" << F.getName()
<< "' does not have terminator!\n";
I->printAsOperand(OS, true);
OS << "\n";
return false;
}
}
// Now directly compute a dominance tree. We don't rely on the pass
// manager to provide this as it isolates us from a potentially
// out-of-date dominator tree and makes it significantly more complex to
// run this code outside of a pass manager.
// FIXME: It's really gross that we have to cast away constness here.
DT.recalculate(const_cast<Function &>(F));
Broken = false;
// FIXME: We strip const here because the inst visitor strips const.
visit(const_cast<Function &>(F));
InstsInThisBlock.clear();
SawFrameEscape = false;
return !Broken;
}
bool verify(const Module &M) {
this->M = &M;
Context = &M.getContext();
Broken = false;
// Scan through, checking all of the external function's linkage now...
for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
visitGlobalValue(*I);
// Check to make sure function prototypes are okay.
if (I->isDeclaration())
visitFunction(*I);
}
// Now that we've visited every function, verify that we never asked to
// recover a frame index that wasn't escaped.
verifyFrameRecoverIndices();
for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I)
visitGlobalVariable(*I);
for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
I != E; ++I)
visitGlobalAlias(*I);
for (Module::const_named_metadata_iterator I = M.named_metadata_begin(),
E = M.named_metadata_end();
I != E; ++I)
visitNamedMDNode(*I);
for (const StringMapEntry<Comdat> &SMEC : M.getComdatSymbolTable())
visitComdat(SMEC.getValue());
visitModuleFlags(M);
visitModuleIdents(M);
// Verify type referneces last.
verifyTypeRefs();
return !Broken;
}
private:
// Verification methods...
void visitGlobalValue(const GlobalValue &GV);
void visitGlobalVariable(const GlobalVariable &GV);
void visitGlobalAlias(const GlobalAlias &GA);
void visitAliaseeSubExpr(const GlobalAlias &A, const Constant &C);
void visitAliaseeSubExpr(SmallPtrSetImpl<const GlobalAlias *> &Visited,
const GlobalAlias &A, const Constant &C);
void visitNamedMDNode(const NamedMDNode &NMD);
void visitMDNode(const MDNode &MD);
void visitMetadataAsValue(const MetadataAsValue &MD, Function *F);
void visitValueAsMetadata(const ValueAsMetadata &MD, Function *F);
void visitComdat(const Comdat &C);
void visitModuleIdents(const Module &M);
void visitModuleFlags(const Module &M);
void visitModuleFlag(const MDNode *Op,
DenseMap<const MDString *, const MDNode *> &SeenIDs,
SmallVectorImpl<const MDNode *> &Requirements);
void visitFunction(const Function &F);
void visitBasicBlock(BasicBlock &BB);
void visitRangeMetadata(Instruction& I, MDNode* Range, Type* Ty);
template <class Ty> bool isValidMetadataArray(const MDTuple &N);
#define HANDLE_SPECIALIZED_MDNODE_LEAF(CLASS) void visit##CLASS(const CLASS &N);
#include "llvm/IR/Metadata.def"
void visitDIScope(const DIScope &N);
void visitDIDerivedTypeBase(const DIDerivedTypeBase &N);
void visitDIVariable(const DIVariable &N);
void visitDILexicalBlockBase(const DILexicalBlockBase &N);
void visitDITemplateParameter(const DITemplateParameter &N);
void visitTemplateParams(const MDNode &N, const Metadata &RawParams);
/// \brief Check for a valid string-based type reference.
///
/// Checks if \c MD is a string-based type reference. If it is, keeps track
/// of it (and its user, \c N) for error messages later.
bool isValidUUID(const MDNode &N, const Metadata *MD);
/// \brief Check for a valid type reference.
///
/// Checks for subclasses of \a DIType, or \a isValidUUID().
bool isTypeRef(const MDNode &N, const Metadata *MD);
/// \brief Check for a valid scope reference.
///
/// Checks for subclasses of \a DIScope, or \a isValidUUID().
bool isScopeRef(const MDNode &N, const Metadata *MD);
/// \brief Check for a valid debug info reference.
///
/// Checks for subclasses of \a DINode, or \a isValidUUID().
bool isDIRef(const MDNode &N, const Metadata *MD);
// InstVisitor overrides...
using InstVisitor<Verifier>::visit;
void visit(Instruction &I);
void visitTruncInst(TruncInst &I);
void visitZExtInst(ZExtInst &I);
void visitSExtInst(SExtInst &I);
void visitFPTruncInst(FPTruncInst &I);
void visitFPExtInst(FPExtInst &I);
void visitFPToUIInst(FPToUIInst &I);
void visitFPToSIInst(FPToSIInst &I);
void visitUIToFPInst(UIToFPInst &I);
void visitSIToFPInst(SIToFPInst &I);
void visitIntToPtrInst(IntToPtrInst &I);
void visitPtrToIntInst(PtrToIntInst &I);
void visitBitCastInst(BitCastInst &I);
void visitAddrSpaceCastInst(AddrSpaceCastInst &I);
void visitPHINode(PHINode &PN);
void visitBinaryOperator(BinaryOperator &B);
void visitICmpInst(ICmpInst &IC);
void visitFCmpInst(FCmpInst &FC);
void visitExtractElementInst(ExtractElementInst &EI);
void visitInsertElementInst(InsertElementInst &EI);
void visitShuffleVectorInst(ShuffleVectorInst &EI);
void visitVAArgInst(VAArgInst &VAA) { visitInstruction(VAA); }
void visitCallInst(CallInst &CI);
void visitInvokeInst(InvokeInst &II);
void visitGetElementPtrInst(GetElementPtrInst &GEP);
void visitLoadInst(LoadInst &LI);
void visitStoreInst(StoreInst &SI);
void verifyDominatesUse(Instruction &I, unsigned i);
void visitInstruction(Instruction &I);
void visitTerminatorInst(TerminatorInst &I);
void visitBranchInst(BranchInst &BI);
void visitReturnInst(ReturnInst &RI);
void visitSwitchInst(SwitchInst &SI);
void visitIndirectBrInst(IndirectBrInst &BI);
void visitSelectInst(SelectInst &SI);
void visitUserOp1(Instruction &I);
void visitUserOp2(Instruction &I) { visitUserOp1(I); }
void visitIntrinsicCallSite(Intrinsic::ID ID, CallSite CS);
template <class DbgIntrinsicTy>
void visitDbgIntrinsic(StringRef Kind, DbgIntrinsicTy &DII);
void visitAtomicCmpXchgInst(AtomicCmpXchgInst &CXI);
void visitAtomicRMWInst(AtomicRMWInst &RMWI);
void visitFenceInst(FenceInst &FI);
void visitAllocaInst(AllocaInst &AI);
void visitExtractValueInst(ExtractValueInst &EVI);
void visitInsertValueInst(InsertValueInst &IVI);
void visitLandingPadInst(LandingPadInst &LPI);
void VerifyCallSite(CallSite CS);
void verifyMustTailCall(CallInst &CI);
bool PerformTypeCheck(Intrinsic::ID ID, Function *F, Type *Ty, int VT,
unsigned ArgNo, std::string &Suffix);
bool VerifyIntrinsicType(Type *Ty, ArrayRef<Intrinsic::IITDescriptor> &Infos,
SmallVectorImpl<Type *> &ArgTys);
bool VerifyIntrinsicIsVarArg(bool isVarArg,
ArrayRef<Intrinsic::IITDescriptor> &Infos);
bool VerifyAttributeCount(AttributeSet Attrs, unsigned Params);
void VerifyAttributeTypes(AttributeSet Attrs, unsigned Idx, bool isFunction,
const Value *V);
void VerifyParameterAttrs(AttributeSet Attrs, unsigned Idx, Type *Ty,
bool isReturnValue, const Value *V);
void VerifyFunctionAttrs(FunctionType *FT, AttributeSet Attrs,
const Value *V);
void VerifyFunctionMetadata(
const SmallVector<std::pair<unsigned, MDNode *>, 4> MDs);
void VerifyConstantExprBitcastType(const ConstantExpr *CE);
void VerifyStatepoint(ImmutableCallSite CS);
void verifyFrameRecoverIndices();
// Module-level debug info verification...
void verifyTypeRefs();
template <class MapTy>
void verifyBitPieceExpression(const DbgInfoIntrinsic &I,
const MapTy &TypeRefs);
void visitUnresolvedTypeRef(const MDString *S, const MDNode *N);
};
} // End anonymous namespace
// Assert - We know that cond should be true, if not print an error message.
#define Assert(C, ...) \
do { if (!(C)) { CheckFailed(__VA_ARGS__); return; } } while (0)
void Verifier::visit(Instruction &I) {
for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
Assert(I.getOperand(i) != nullptr, "Operand is null", &I);
InstVisitor<Verifier>::visit(I);
}
void Verifier::visitGlobalValue(const GlobalValue &GV) {
Assert(!GV.isDeclaration() || GV.hasExternalLinkage() ||
GV.hasExternalWeakLinkage(),
"Global is external, but doesn't have external or weak linkage!", &GV);
Assert(GV.getAlignment() <= Value::MaximumAlignment,
"huge alignment values are unsupported", &GV);
Assert(!GV.hasAppendingLinkage() || isa<GlobalVariable>(GV),
"Only global variables can have appending linkage!", &GV);
if (GV.hasAppendingLinkage()) {
const GlobalVariable *GVar = dyn_cast<GlobalVariable>(&GV);
Assert(GVar && GVar->getValueType()->isArrayTy(),
"Only global arrays can have appending linkage!", GVar);
}
if (GV.isDeclarationForLinker())
Assert(!GV.hasComdat(), "Declaration may not be in a Comdat!", &GV);
}
void Verifier::visitGlobalVariable(const GlobalVariable &GV) {
if (GV.hasInitializer()) {
Assert(GV.getInitializer()->getType() == GV.getType()->getElementType(),
"Global variable initializer type does not match global "
"variable type!",
&GV);
// If the global has common linkage, it must have a zero initializer and
// cannot be constant.
if (GV.hasCommonLinkage()) {
Assert(GV.getInitializer()->isNullValue(),
"'common' global must have a zero initializer!", &GV);
Assert(!GV.isConstant(), "'common' global may not be marked constant!",
&GV);
Assert(!GV.hasComdat(), "'common' global may not be in a Comdat!", &GV);
}
} else {
Assert(GV.hasExternalLinkage() || GV.hasExternalWeakLinkage(),
"invalid linkage type for global declaration", &GV);
}
if (GV.hasName() && (GV.getName() == "llvm.global_ctors" ||
GV.getName() == "llvm.global_dtors")) {
Assert(!GV.hasInitializer() || GV.hasAppendingLinkage(),
"invalid linkage for intrinsic global variable", &GV);
// Don't worry about emitting an error for it not being an array,
// visitGlobalValue will complain on appending non-array.
if (ArrayType *ATy = dyn_cast<ArrayType>(GV.getValueType())) {
StructType *STy = dyn_cast<StructType>(ATy->getElementType());
PointerType *FuncPtrTy =
FunctionType::get(Type::getVoidTy(*Context), false)->getPointerTo();
// FIXME: Reject the 2-field form in LLVM 4.0.
Assert(STy &&
(STy->getNumElements() == 2 || STy->getNumElements() == 3) &&
STy->getTypeAtIndex(0u)->isIntegerTy(32) &&
STy->getTypeAtIndex(1) == FuncPtrTy,
"wrong type for intrinsic global variable", &GV);
if (STy->getNumElements() == 3) {
Type *ETy = STy->getTypeAtIndex(2);
Assert(ETy->isPointerTy() &&
cast<PointerType>(ETy)->getElementType()->isIntegerTy(8),
"wrong type for intrinsic global variable", &GV);
}
}
}
if (GV.hasName() && (GV.getName() == "llvm.used" ||
GV.getName() == "llvm.compiler.used")) {
Assert(!GV.hasInitializer() || GV.hasAppendingLinkage(),
"invalid linkage for intrinsic global variable", &GV);
Type *GVType = GV.getValueType();
if (ArrayType *ATy = dyn_cast<ArrayType>(GVType)) {
PointerType *PTy = dyn_cast<PointerType>(ATy->getElementType());
Assert(PTy, "wrong type for intrinsic global variable", &GV);
if (GV.hasInitializer()) {
const Constant *Init = GV.getInitializer();
const ConstantArray *InitArray = dyn_cast<ConstantArray>(Init);
Assert(InitArray, "wrong initalizer for intrinsic global variable",
Init);
for (unsigned i = 0, e = InitArray->getNumOperands(); i != e; ++i) {
Value *V = Init->getOperand(i)->stripPointerCastsNoFollowAliases();
Assert(isa<GlobalVariable>(V) || isa<Function>(V) ||
isa<GlobalAlias>(V),
"invalid llvm.used member", V);
Assert(V->hasName(), "members of llvm.used must be named", V);
}
}
}
}
Assert(!GV.hasDLLImportStorageClass() ||
(GV.isDeclaration() && GV.hasExternalLinkage()) ||
GV.hasAvailableExternallyLinkage(),
"Global is marked as dllimport, but not external", &GV);
if (!GV.hasInitializer()) {
visitGlobalValue(GV);
return;
}
// Walk any aggregate initializers looking for bitcasts between address spaces
SmallPtrSet<const Value *, 4> Visited;
SmallVector<const Value *, 4> WorkStack;
WorkStack.push_back(cast<Value>(GV.getInitializer()));
while (!WorkStack.empty()) {
const Value *V = WorkStack.pop_back_val();
if (!Visited.insert(V).second)
continue;
if (const User *U = dyn_cast<User>(V)) {
WorkStack.append(U->op_begin(), U->op_end());
}
if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
VerifyConstantExprBitcastType(CE);
if (Broken)
return;
}
}
visitGlobalValue(GV);
}
void Verifier::visitAliaseeSubExpr(const GlobalAlias &GA, const Constant &C) {
SmallPtrSet<const GlobalAlias*, 4> Visited;
Visited.insert(&GA);
visitAliaseeSubExpr(Visited, GA, C);
}
void Verifier::visitAliaseeSubExpr(SmallPtrSetImpl<const GlobalAlias*> &Visited,
const GlobalAlias &GA, const Constant &C) {
if (const auto *GV = dyn_cast<GlobalValue>(&C)) {
Assert(!GV->isDeclaration(), "Alias must point to a definition", &GA);
if (const auto *GA2 = dyn_cast<GlobalAlias>(GV)) {
Assert(Visited.insert(GA2).second, "Aliases cannot form a cycle", &GA);
Assert(!GA2->mayBeOverridden(), "Alias cannot point to a weak alias",
&GA);
} else {
// Only continue verifying subexpressions of GlobalAliases.
// Do not recurse into global initializers.
return;
}
}
if (const auto *CE = dyn_cast<ConstantExpr>(&C))
VerifyConstantExprBitcastType(CE);
for (const Use &U : C.operands()) {
Value *V = &*U;
if (const auto *GA2 = dyn_cast<GlobalAlias>(V))
visitAliaseeSubExpr(Visited, GA, *GA2->getAliasee());
else if (const auto *C2 = dyn_cast<Constant>(V))
visitAliaseeSubExpr(Visited, GA, *C2);
}
}
void Verifier::visitGlobalAlias(const GlobalAlias &GA) {
Assert(GlobalAlias::isValidLinkage(GA.getLinkage()),
"Alias should have private, internal, linkonce, weak, linkonce_odr, "
"weak_odr, or external linkage!",
&GA);
const Constant *Aliasee = GA.getAliasee();
Assert(Aliasee, "Aliasee cannot be NULL!", &GA);
Assert(GA.getType() == Aliasee->getType(),
"Alias and aliasee types should match!", &GA);
Assert(isa<GlobalValue>(Aliasee) || isa<ConstantExpr>(Aliasee),
"Aliasee should be either GlobalValue or ConstantExpr", &GA);
visitAliaseeSubExpr(GA, *Aliasee);
visitGlobalValue(GA);
}
void Verifier::visitNamedMDNode(const NamedMDNode &NMD) {
for (unsigned i = 0, e = NMD.getNumOperands(); i != e; ++i) {
MDNode *MD = NMD.getOperand(i);
if (NMD.getName() == "llvm.dbg.cu") {
Assert(MD && isa<DICompileUnit>(MD), "invalid compile unit", &NMD, MD);
}
if (!MD)
continue;
visitMDNode(*MD);
}
}
void Verifier::visitMDNode(const MDNode &MD) {
// Only visit each node once. Metadata can be mutually recursive, so this
// avoids infinite recursion here, as well as being an optimization.
if (!MDNodes.insert(&MD).second)
return;
switch (MD.getMetadataID()) {
default:
llvm_unreachable("Invalid MDNode subclass");
case Metadata::MDTupleKind:
break;
#define HANDLE_SPECIALIZED_MDNODE_LEAF(CLASS) \
case Metadata::CLASS##Kind: \
visit##CLASS(cast<CLASS>(MD)); \
break;
#include "llvm/IR/Metadata.def"
}
for (unsigned i = 0, e = MD.getNumOperands(); i != e; ++i) {
Metadata *Op = MD.getOperand(i);
if (!Op)
continue;
Assert(!isa<LocalAsMetadata>(Op), "Invalid operand for global metadata!",
&MD, Op);
if (auto *N = dyn_cast<MDNode>(Op)) {
visitMDNode(*N);
continue;
}
if (auto *V = dyn_cast<ValueAsMetadata>(Op)) {
visitValueAsMetadata(*V, nullptr);
continue;
}
}
// Check these last, so we diagnose problems in operands first.
Assert(!MD.isTemporary(), "Expected no forward declarations!", &MD);
Assert(MD.isResolved(), "All nodes should be resolved!", &MD);
}
void Verifier::visitValueAsMetadata(const ValueAsMetadata &MD, Function *F) {
Assert(MD.getValue(), "Expected valid value", &MD);
Assert(!MD.getValue()->getType()->isMetadataTy(),
"Unexpected metadata round-trip through values", &MD, MD.getValue());
auto *L = dyn_cast<LocalAsMetadata>(&MD);
if (!L)
return;
Assert(F, "function-local metadata used outside a function", L);
// If this was an instruction, bb, or argument, verify that it is in the
// function that we expect.
Function *ActualF = nullptr;
if (Instruction *I = dyn_cast<Instruction>(L->getValue())) {
Assert(I->getParent(), "function-local metadata not in basic block", L, I);
ActualF = I->getParent()->getParent();
} else if (BasicBlock *BB = dyn_cast<BasicBlock>(L->getValue()))
ActualF = BB->getParent();
else if (Argument *A = dyn_cast<Argument>(L->getValue()))
ActualF = A->getParent();
assert(ActualF && "Unimplemented function local metadata case!");
Assert(ActualF == F, "function-local metadata used in wrong function", L);
}
void Verifier::visitMetadataAsValue(const MetadataAsValue &MDV, Function *F) {
Metadata *MD = MDV.getMetadata();
if (auto *N = dyn_cast<MDNode>(MD)) {
visitMDNode(*N);
return;
}
// Only visit each node once. Metadata can be mutually recursive, so this
// avoids infinite recursion here, as well as being an optimization.
if (!MDNodes.insert(MD).second)
return;
if (auto *V = dyn_cast<ValueAsMetadata>(MD))
visitValueAsMetadata(*V, F);
}
bool Verifier::isValidUUID(const MDNode &N, const Metadata *MD) {
auto *S = dyn_cast<MDString>(MD);
if (!S)
return false;
if (S->getString().empty())
return false;
// Keep track of names of types referenced via UUID so we can check that they
// actually exist.
UnresolvedTypeRefs.insert(std::make_pair(S, &N));
return true;
}
/// \brief Check if a value can be a reference to a type.
bool Verifier::isTypeRef(const MDNode &N, const Metadata *MD) {
return !MD || isValidUUID(N, MD) || isa<DIType>(MD);
}
/// \brief Check if a value can be a ScopeRef.
bool Verifier::isScopeRef(const MDNode &N, const Metadata *MD) {
return !MD || isValidUUID(N, MD) || isa<DIScope>(MD);
}
/// \brief Check if a value can be a debug info ref.
bool Verifier::isDIRef(const MDNode &N, const Metadata *MD) {
return !MD || isValidUUID(N, MD) || isa<DINode>(MD);
}
template <class Ty>
bool isValidMetadataArrayImpl(const MDTuple &N, bool AllowNull) {
for (Metadata *MD : N.operands()) {
if (MD) {
if (!isa<Ty>(MD))
return false;
} else {
if (!AllowNull)
return false;
}
}
return true;
}
template <class Ty>
bool isValidMetadataArray(const MDTuple &N) {
return isValidMetadataArrayImpl<Ty>(N, /* AllowNull */ false);
}
template <class Ty>
bool isValidMetadataNullArray(const MDTuple &N) {
return isValidMetadataArrayImpl<Ty>(N, /* AllowNull */ true);
}
void Verifier::visitDILocation(const DILocation &N) {
Assert(N.getRawScope() && isa<DILocalScope>(N.getRawScope()),
"location requires a valid scope", &N, N.getRawScope());
if (auto *IA = N.getRawInlinedAt())
Assert(isa<DILocation>(IA), "inlined-at should be a location", &N, IA);
}
void Verifier::visitGenericDINode(const GenericDINode &N) {
Assert(N.getTag(), "invalid tag", &N);
}
void Verifier::visitDIScope(const DIScope &N) {
if (auto *F = N.getRawFile())
Assert(isa<DIFile>(F), "invalid file", &N, F);
}
void Verifier::visitDISubrange(const DISubrange &N) {
Assert(N.getTag() == dwarf::DW_TAG_subrange_type, "invalid tag", &N);
Assert(N.getCount() >= -1, "invalid subrange count", &N);
}
void Verifier::visitDIEnumerator(const DIEnumerator &N) {
Assert(N.getTag() == dwarf::DW_TAG_enumerator, "invalid tag", &N);
}
void Verifier::visitDIBasicType(const DIBasicType &N) {
Assert(N.getTag() == dwarf::DW_TAG_base_type ||
N.getTag() == dwarf::DW_TAG_unspecified_type,
"invalid tag", &N);
}
void Verifier::visitDIDerivedTypeBase(const DIDerivedTypeBase &N) {
// Common scope checks.
visitDIScope(N);
Assert(isScopeRef(N, N.getScope()), "invalid scope", &N, N.getScope());
Assert(isTypeRef(N, N.getBaseType()), "invalid base type", &N,
N.getBaseType());
// FIXME: Sink this into the subclass verifies.
if (!N.getFile() || N.getFile()->getFilename().empty()) {
// Check whether the filename is allowed to be empty.
uint16_t Tag = N.getTag();
Assert(
Tag == dwarf::DW_TAG_const_type || Tag == dwarf::DW_TAG_volatile_type ||
Tag == dwarf::DW_TAG_pointer_type ||
Tag == dwarf::DW_TAG_ptr_to_member_type ||
Tag == dwarf::DW_TAG_reference_type ||
Tag == dwarf::DW_TAG_rvalue_reference_type ||
Tag == dwarf::DW_TAG_restrict_type ||
Tag == dwarf::DW_TAG_array_type ||
Tag == dwarf::DW_TAG_enumeration_type ||
Tag == dwarf::DW_TAG_subroutine_type ||
Tag == dwarf::DW_TAG_inheritance || Tag == dwarf::DW_TAG_friend ||
Tag == dwarf::DW_TAG_structure_type ||
Tag == dwarf::DW_TAG_member || Tag == dwarf::DW_TAG_typedef,
"derived/composite type requires a filename", &N, N.getFile());
}
}
void Verifier::visitDIDerivedType(const DIDerivedType &N) {
// Common derived type checks.
visitDIDerivedTypeBase(N);
Assert(N.getTag() == dwarf::DW_TAG_typedef ||
N.getTag() == dwarf::DW_TAG_pointer_type ||
N.getTag() == dwarf::DW_TAG_ptr_to_member_type ||
N.getTag() == dwarf::DW_TAG_reference_type ||
N.getTag() == dwarf::DW_TAG_rvalue_reference_type ||
N.getTag() == dwarf::DW_TAG_const_type ||
N.getTag() == dwarf::DW_TAG_volatile_type ||
N.getTag() == dwarf::DW_TAG_restrict_type ||
N.getTag() == dwarf::DW_TAG_member ||
N.getTag() == dwarf::DW_TAG_inheritance ||
N.getTag() == dwarf::DW_TAG_friend,
"invalid tag", &N);
if (N.getTag() == dwarf::DW_TAG_ptr_to_member_type) {
Assert(isTypeRef(N, N.getExtraData()), "invalid pointer to member type", &N,
N.getExtraData());
}
}
static bool hasConflictingReferenceFlags(unsigned Flags) {
return (Flags & DINode::FlagLValueReference) &&
(Flags & DINode::FlagRValueReference);
}
void Verifier::visitTemplateParams(const MDNode &N, const Metadata &RawParams) {
auto *Params = dyn_cast<MDTuple>(&RawParams);
Assert(Params, "invalid template params", &N, &RawParams);
for (Metadata *Op : Params->operands()) {
Assert(Op && isa<DITemplateParameter>(Op), "invalid template parameter", &N,
Params, Op);
}
}
void Verifier::visitDICompositeType(const DICompositeType &N) {
// Common derived type checks.
visitDIDerivedTypeBase(N);
Assert(N.getTag() == dwarf::DW_TAG_array_type ||
N.getTag() == dwarf::DW_TAG_structure_type ||
N.getTag() == dwarf::DW_TAG_union_type ||
N.getTag() == dwarf::DW_TAG_enumeration_type ||
N.getTag() == dwarf::DW_TAG_subroutine_type ||
N.getTag() == dwarf::DW_TAG_class_type,
"invalid tag", &N);
Assert(!N.getRawElements() || isa<MDTuple>(N.getRawElements()),
"invalid composite elements", &N, N.getRawElements());
Assert(isTypeRef(N, N.getRawVTableHolder()), "invalid vtable holder", &N,
N.getRawVTableHolder());
Assert(!N.getRawElements() || isa<MDTuple>(N.getRawElements()),
"invalid composite elements", &N, N.getRawElements());
Assert(!hasConflictingReferenceFlags(N.getFlags()), "invalid reference flags",
&N);
if (auto *Params = N.getRawTemplateParams())
visitTemplateParams(N, *Params);
}
void Verifier::visitDISubroutineType(const DISubroutineType &N) {
Assert(N.getTag() == dwarf::DW_TAG_subroutine_type, "invalid tag", &N);
if (auto *Types = N.getRawTypeArray()) {
Assert(isa<MDTuple>(Types), "invalid composite elements", &N, Types);
for (Metadata *Ty : N.getTypeArray()->operands()) {
Assert(isTypeRef(N, Ty), "invalid subroutine type ref", &N, Types, Ty);
}
}
Assert(!hasConflictingReferenceFlags(N.getFlags()), "invalid reference flags",
&N);
}
void Verifier::visitDIFile(const DIFile &N) {
Assert(N.getTag() == dwarf::DW_TAG_file_type, "invalid tag", &N);
}
void Verifier::visitDICompileUnit(const DICompileUnit &N) {
Assert(N.getTag() == dwarf::DW_TAG_compile_unit, "invalid tag", &N);
// Don't bother verifying the compilation directory or producer string
// as those could be empty.
Assert(N.getRawFile() && isa<DIFile>(N.getRawFile()), "invalid file", &N,
N.getRawFile());
Assert(!N.getFile()->getFilename().empty(), "invalid filename", &N,
N.getFile());
if (auto *Array = N.getRawEnumTypes()) {
Assert(isa<MDTuple>(Array), "invalid enum list", &N, Array);
for (Metadata *Op : N.getEnumTypes()->operands()) {
auto *Enum = dyn_cast_or_null<DICompositeType>(Op);
Assert(Enum && Enum->getTag() == dwarf::DW_TAG_enumeration_type,
"invalid enum type", &N, N.getEnumTypes(), Op);
}
}
if (auto *Array = N.getRawRetainedTypes()) {
Assert(isa<MDTuple>(Array), "invalid retained type list", &N, Array);
for (Metadata *Op : N.getRetainedTypes()->operands()) {
Assert(Op && isa<DIType>(Op), "invalid retained type", &N, Op);
}
}
if (auto *Array = N.getRawSubprograms()) {
Assert(isa<MDTuple>(Array), "invalid subprogram list", &N, Array);
for (Metadata *Op : N.getSubprograms()->operands()) {
Assert(Op && isa<DISubprogram>(Op), "invalid subprogram ref", &N, Op);
}
}
if (auto *Array = N.getRawGlobalVariables()) {
Assert(isa<MDTuple>(Array), "invalid global variable list", &N, Array);
for (Metadata *Op : N.getGlobalVariables()->operands()) {
Assert(Op && isa<DIGlobalVariable>(Op), "invalid global variable ref", &N,
Op);
}
}
if (auto *Array = N.getRawImportedEntities()) {
Assert(isa<MDTuple>(Array), "invalid imported entity list", &N, Array);
for (Metadata *Op : N.getImportedEntities()->operands()) {
Assert(Op && isa<DIImportedEntity>(Op), "invalid imported entity ref", &N,
Op);
}
}
}
void Verifier::visitDISubprogram(const DISubprogram &N) {
Assert(N.getTag() == dwarf::DW_TAG_subprogram, "invalid tag", &N);
Assert(isScopeRef(N, N.getRawScope()), "invalid scope", &N, N.getRawScope());
if (auto *T = N.getRawType())
Assert(isa<DISubroutineType>(T), "invalid subroutine type", &N, T);
Assert(isTypeRef(N, N.getRawContainingType()), "invalid containing type", &N,
N.getRawContainingType());
if (auto *RawF = N.getRawFunction()) {
auto *FMD = dyn_cast<ConstantAsMetadata>(RawF);
auto *F = FMD ? FMD->getValue() : nullptr;
auto *FT = F ? dyn_cast<PointerType>(F->getType()) : nullptr;
Assert(F && FT && isa<FunctionType>(FT->getElementType()),
"invalid function", &N, F, FT);
}
if (auto *Params = N.getRawTemplateParams())
visitTemplateParams(N, *Params);
if (auto *S = N.getRawDeclaration()) {
Assert(isa<DISubprogram>(S) && !cast<DISubprogram>(S)->isDefinition(),
"invalid subprogram declaration", &N, S);
}
if (auto *RawVars = N.getRawVariables()) {
auto *Vars = dyn_cast<MDTuple>(RawVars);
Assert(Vars, "invalid variable list", &N, RawVars);
for (Metadata *Op : Vars->operands()) {
Assert(Op && isa<DILocalVariable>(Op), "invalid local variable", &N, Vars,
Op);
}
}
Assert(!hasConflictingReferenceFlags(N.getFlags()), "invalid reference flags",
&N);
auto *F = N.getFunction();
if (!F)
return;
// Check that all !dbg attachments lead to back to N (or, at least, another
// subprogram that describes the same function).
//
// FIXME: Check this incrementally while visiting !dbg attachments.
// FIXME: Only check when N is the canonical subprogram for F.
SmallPtrSet<const MDNode *, 32> Seen;
for (auto &BB : *F)
for (auto &I : BB) {
// Be careful about using DILocation here since we might be dealing with
// broken code (this is the Verifier after all).
DILocation *DL =
dyn_cast_or_null<DILocation>(I.getDebugLoc().getAsMDNode());
if (!DL)
continue;
if (!Seen.insert(DL).second)
continue;
DILocalScope *Scope = DL->getInlinedAtScope();
if (Scope && !Seen.insert(Scope).second)
continue;
DISubprogram *SP = Scope ? Scope->getSubprogram() : nullptr;
if (SP && !Seen.insert(SP).second)
continue;
// FIXME: Once N is canonical, check "SP == &N".
Assert(SP->describes(F),
"!dbg attachment points at wrong subprogram for function", &N, F,
&I, DL, Scope, SP);
}
}
void Verifier::visitDILexicalBlockBase(const DILexicalBlockBase &N) {
Assert(N.getTag() == dwarf::DW_TAG_lexical_block, "invalid tag", &N);
Assert(N.getRawScope() && isa<DILocalScope>(N.getRawScope()),
"invalid local scope", &N, N.getRawScope());
}
void Verifier::visitDILexicalBlock(const DILexicalBlock &N) {
visitDILexicalBlockBase(N);
Assert(N.getLine() || !N.getColumn(),
"cannot have column info without line info", &N);
}
void Verifier::visitDILexicalBlockFile(const DILexicalBlockFile &N) {
visitDILexicalBlockBase(N);
}
void Verifier::visitDINamespace(const DINamespace &N) {
Assert(N.getTag() == dwarf::DW_TAG_namespace, "invalid tag", &N);
if (auto *S = N.getRawScope())
Assert(isa<DIScope>(S), "invalid scope ref", &N, S);
}
void Verifier::visitDIModule(const DIModule &N) {
Assert(N.getTag() == dwarf::DW_TAG_module, "invalid tag", &N);
Assert(!N.getName().empty(), "anonymous module", &N);
}
void Verifier::visitDITemplateParameter(const DITemplateParameter &N) {
Assert(isTypeRef(N, N.getType()), "invalid type ref", &N, N.getType());
}
void Verifier::visitDITemplateTypeParameter(const DITemplateTypeParameter &N) {
visitDITemplateParameter(N);
Assert(N.getTag() == dwarf::DW_TAG_template_type_parameter, "invalid tag",
&N);
}
void Verifier::visitDITemplateValueParameter(
const DITemplateValueParameter &N) {
visitDITemplateParameter(N);
Assert(N.getTag() == dwarf::DW_TAG_template_value_parameter ||
N.getTag() == dwarf::DW_TAG_GNU_template_template_param ||
N.getTag() == dwarf::DW_TAG_GNU_template_parameter_pack,
"invalid tag", &N);
}
void Verifier::visitDIVariable(const DIVariable &N) {
if (auto *S = N.getRawScope())
Assert(isa<DIScope>(S), "invalid scope", &N, S);
Assert(isTypeRef(N, N.getRawType()), "invalid type ref", &N, N.getRawType());
if (auto *F = N.getRawFile())
Assert(isa<DIFile>(F), "invalid file", &N, F);
}
void Verifier::visitDIGlobalVariable(const DIGlobalVariable &N) {
// Checks common to all variables.
visitDIVariable(N);
Assert(N.getTag() == dwarf::DW_TAG_variable, "invalid tag", &N);
Assert(!N.getName().empty(), "missing global variable name", &N);
if (auto *V = N.getRawVariable()) {
Assert(isa<ConstantAsMetadata>(V) &&
!isa<Function>(cast<ConstantAsMetadata>(V)->getValue()),
"invalid global varaible ref", &N, V);
}
if (auto *Member = N.getRawStaticDataMemberDeclaration()) {
Assert(isa<DIDerivedType>(Member), "invalid static data member declaration",
&N, Member);
}
}
void Verifier::visitDILocalVariable(const DILocalVariable &N) {
// Checks common to all variables.
visitDIVariable(N);
Assert(N.getTag() == dwarf::DW_TAG_auto_variable ||
N.getTag() == dwarf::DW_TAG_arg_variable,
"invalid tag", &N);
Assert(N.getRawScope() && isa<DILocalScope>(N.getRawScope()),
"local variable requires a valid scope", &N, N.getRawScope());
}
void Verifier::visitDIExpression(const DIExpression &N) {
Assert(N.isValid(), "invalid expression", &N);
}
void Verifier::visitDIObjCProperty(const DIObjCProperty &N) {
Assert(N.getTag() == dwarf::DW_TAG_APPLE_property, "invalid tag", &N);
if (auto *T = N.getRawType())
Assert(isTypeRef(N, T), "invalid type ref", &N, T);
if (auto *F = N.getRawFile())
Assert(isa<DIFile>(F), "invalid file", &N, F);
}
void Verifier::visitDIImportedEntity(const DIImportedEntity &N) {
Assert(N.getTag() == dwarf::DW_TAG_imported_module ||
N.getTag() == dwarf::DW_TAG_imported_declaration,
"invalid tag", &N);
if (auto *S = N.getRawScope())
Assert(isa<DIScope>(S), "invalid scope for imported entity", &N, S);
Assert(isDIRef(N, N.getEntity()), "invalid imported entity", &N,
N.getEntity());
}
void Verifier::visitComdat(const Comdat &C) {
// The Module is invalid if the GlobalValue has private linkage. Entities
// with private linkage don't have entries in the symbol table.
if (const GlobalValue *GV = M->getNamedValue(C.getName()))
Assert(!GV->hasPrivateLinkage(), "comdat global value has private linkage",
GV);
}
void Verifier::visitModuleIdents(const Module &M) {
const NamedMDNode *Idents = M.getNamedMetadata("llvm.ident");
if (!Idents)
return;
// llvm.ident takes a list of metadata entry. Each entry has only one string.
// Scan each llvm.ident entry and make sure that this requirement is met.
for (unsigned i = 0, e = Idents->getNumOperands(); i != e; ++i) {
const MDNode *N = Idents->getOperand(i);
Assert(N->getNumOperands() == 1,
"incorrect number of operands in llvm.ident metadata", N);
Assert(dyn_cast_or_null<MDString>(N->getOperand(0)),
("invalid value for llvm.ident metadata entry operand"
"(the operand should be a string)"),
N->getOperand(0));
}
}
void Verifier::visitModuleFlags(const Module &M) {
const NamedMDNode *Flags = M.getModuleFlagsMetadata();
if (!Flags) return;
// Scan each flag, and track the flags and requirements.
DenseMap<const MDString*, const MDNode*> SeenIDs;
SmallVector<const MDNode*, 16> Requirements;
for (unsigned I = 0, E = Flags->getNumOperands(); I != E; ++I) {
visitModuleFlag(Flags->getOperand(I), SeenIDs, Requirements);
}
// Validate that the requirements in the module are valid.
for (unsigned I = 0, E = Requirements.size(); I != E; ++I) {
const MDNode *Requirement = Requirements[I];
const MDString *Flag = cast<MDString>(Requirement->getOperand(0));
const Metadata *ReqValue = Requirement->getOperand(1);
const MDNode *Op = SeenIDs.lookup(Flag);
if (!Op) {
CheckFailed("invalid requirement on flag, flag is not present in module",
Flag);
continue;
}
if (Op->getOperand(2) != ReqValue) {
CheckFailed(("invalid requirement on flag, "
"flag does not have the required value"),
Flag);
continue;
}
}
}
void
Verifier::visitModuleFlag(const MDNode *Op,
DenseMap<const MDString *, const MDNode *> &SeenIDs,
SmallVectorImpl<const MDNode *> &Requirements) {
// Each module flag should have three arguments, the merge behavior (a
// constant int), the flag ID (an MDString), and the value.
Assert(Op->getNumOperands() == 3,
"incorrect number of operands in module flag", Op);
Module::ModFlagBehavior MFB;
if (!Module::isValidModFlagBehavior(Op->getOperand(0), MFB)) {
Assert(
mdconst::dyn_extract_or_null<ConstantInt>(Op->getOperand(0)),
"invalid behavior operand in module flag (expected constant integer)",
Op->getOperand(0));
Assert(false,
"invalid behavior operand in module flag (unexpected constant)",
Op->getOperand(0));
}
MDString *ID = dyn_cast_or_null<MDString>(Op->getOperand(1));
Assert(ID, "invalid ID operand in module flag (expected metadata string)",
Op->getOperand(1));
// Sanity check the values for behaviors with additional requirements.
switch (MFB) {
case Module::Error:
case Module::Warning:
case Module::Override:
// These behavior types accept any value.
break;
case Module::Require: {
// The value should itself be an MDNode with two operands, a flag ID (an
// MDString), and a value.
MDNode *Value = dyn_cast<MDNode>(Op->getOperand(2));
Assert(Value && Value->getNumOperands() == 2,
"invalid value for 'require' module flag (expected metadata pair)",
Op->getOperand(2));
Assert(isa<MDString>(Value->getOperand(0)),
("invalid value for 'require' module flag "
"(first value operand should be a string)"),
Value->getOperand(0));
// Append it to the list of requirements, to check once all module flags are
// scanned.
Requirements.push_back(Value);
break;
}
case Module::Append:
case Module::AppendUnique: {
// These behavior types require the operand be an MDNode.
Assert(isa<MDNode>(Op->getOperand(2)),
"invalid value for 'append'-type module flag "
"(expected a metadata node)",
Op->getOperand(2));
break;
}
}
// Unless this is a "requires" flag, check the ID is unique.
if (MFB != Module::Require) {
bool Inserted = SeenIDs.insert(std::make_pair(ID, Op)).second;
Assert(Inserted,
"module flag identifiers must be unique (or of 'require' type)", ID);
}
}
void Verifier::VerifyAttributeTypes(AttributeSet Attrs, unsigned Idx,
bool isFunction, const Value *V) {
unsigned Slot = ~0U;
for (unsigned I = 0, E = Attrs.getNumSlots(); I != E; ++I)
if (Attrs.getSlotIndex(I) == Idx) {
Slot = I;
break;
}
assert(Slot != ~0U && "Attribute set inconsistency!");
for (AttributeSet::iterator I = Attrs.begin(Slot), E = Attrs.end(Slot);
I != E; ++I) {
if (I->isStringAttribute())
continue;
if (I->getKindAsEnum() == Attribute::NoReturn ||
I->getKindAsEnum() == Attribute::NoUnwind ||
I->getKindAsEnum() == Attribute::NoInline ||
I->getKindAsEnum() == Attribute::AlwaysInline ||
I->getKindAsEnum() == Attribute::OptimizeForSize ||
I->getKindAsEnum() == Attribute::StackProtect ||
I->getKindAsEnum() == Attribute::StackProtectReq ||
I->getKindAsEnum() == Attribute::StackProtectStrong ||
I->getKindAsEnum() == Attribute::SafeStack ||
I->getKindAsEnum() == Attribute::NoRedZone ||
I->getKindAsEnum() == Attribute::NoImplicitFloat ||
I->getKindAsEnum() == Attribute::Naked ||
I->getKindAsEnum() == Attribute::InlineHint ||
I->getKindAsEnum() == Attribute::StackAlignment ||
I->getKindAsEnum() == Attribute::UWTable ||
I->getKindAsEnum() == Attribute::NonLazyBind ||
I->getKindAsEnum() == Attribute::ReturnsTwice ||
I->getKindAsEnum() == Attribute::SanitizeAddress ||
I->getKindAsEnum() == Attribute::SanitizeThread ||
I->getKindAsEnum() == Attribute::SanitizeMemory ||
I->getKindAsEnum() == Attribute::MinSize ||
I->getKindAsEnum() == Attribute::NoDuplicate ||
I->getKindAsEnum() == Attribute::Builtin ||
I->getKindAsEnum() == Attribute::NoBuiltin ||
I->getKindAsEnum() == Attribute::Cold ||
I->getKindAsEnum() == Attribute::OptimizeNone ||
I->getKindAsEnum() == Attribute::JumpTable ||
I->getKindAsEnum() == Attribute::Convergent ||
I->getKindAsEnum() == Attribute::ArgMemOnly) {
if (!isFunction) {
CheckFailed("Attribute '" + I->getAsString() +
"' only applies to functions!", V);
return;
}
} else if (I->getKindAsEnum() == Attribute::ReadOnly ||
I->getKindAsEnum() == Attribute::ReadNone) {
if (Idx == 0) {
CheckFailed("Attribute '" + I->getAsString() +
"' does not apply to function returns");
return;
}
} else if (isFunction) {
CheckFailed("Attribute '" + I->getAsString() +
"' does not apply to functions!", V);
return;
}
}
}
// VerifyParameterAttrs - Check the given attributes for an argument or return
// value of the specified type. The value V is printed in error messages.
void Verifier::VerifyParameterAttrs(AttributeSet Attrs, unsigned Idx, Type *Ty,
bool isReturnValue, const Value *V) {
if (!Attrs.hasAttributes(Idx))
return;
VerifyAttributeTypes(Attrs, Idx, false, V);
if (isReturnValue)
Assert(!Attrs.hasAttribute(Idx, Attribute::ByVal) &&
!Attrs.hasAttribute(Idx, Attribute::Nest) &&
!Attrs.hasAttribute(Idx, Attribute::StructRet) &&
!Attrs.hasAttribute(Idx, Attribute::NoCapture) &&
!Attrs.hasAttribute(Idx, Attribute::Returned) &&
!Attrs.hasAttribute(Idx, Attribute::InAlloca),
"Attributes 'byval', 'inalloca', 'nest', 'sret', 'nocapture', and "
"'returned' do not apply to return values!",
V);
// Check for mutually incompatible attributes. Only inreg is compatible with
// sret.
unsigned AttrCount = 0;
AttrCount += Attrs.hasAttribute(Idx, Attribute::ByVal);
AttrCount += Attrs.hasAttribute(Idx, Attribute::InAlloca);
AttrCount += Attrs.hasAttribute(Idx, Attribute::StructRet) ||
Attrs.hasAttribute(Idx, Attribute::InReg);
AttrCount += Attrs.hasAttribute(Idx, Attribute::Nest);
Assert(AttrCount <= 1, "Attributes 'byval', 'inalloca', 'inreg', 'nest', "
"and 'sret' are incompatible!",
V);
Assert(!(Attrs.hasAttribute(Idx, Attribute::InAlloca) &&
Attrs.hasAttribute(Idx, Attribute::ReadOnly)),
"Attributes "
"'inalloca and readonly' are incompatible!",
V);
Assert(!(Attrs.hasAttribute(Idx, Attribute::StructRet) &&
Attrs.hasAttribute(Idx, Attribute::Returned)),
"Attributes "
"'sret and returned' are incompatible!",
V);
Assert(!(Attrs.hasAttribute(Idx, Attribute::ZExt) &&
Attrs.hasAttribute(Idx, Attribute::SExt)),
"Attributes "
"'zeroext and signext' are incompatible!",
V);
Assert(!(Attrs.hasAttribute(Idx, Attribute::ReadNone) &&
Attrs.hasAttribute(Idx, Attribute::ReadOnly)),
"Attributes "
"'readnone and readonly' are incompatible!",
V);
Assert(!(Attrs.hasAttribute(Idx, Attribute::NoInline) &&
Attrs.hasAttribute(Idx, Attribute::AlwaysInline)),
"Attributes "
"'noinline and alwaysinline' are incompatible!",
V);
Assert(!AttrBuilder(Attrs, Idx)
.overlaps(AttributeFuncs::typeIncompatible(Ty)),
"Wrong types for attribute: " +
AttributeSet::get(*Context, Idx,
AttributeFuncs::typeIncompatible(Ty)).getAsString(Idx),
V);
if (PointerType *PTy = dyn_cast<PointerType>(Ty)) {
SmallPtrSet<const Type*, 4> Visited;
if (!PTy->getElementType()->isSized(&Visited)) {
Assert(!Attrs.hasAttribute(Idx, Attribute::ByVal) &&
!Attrs.hasAttribute(Idx, Attribute::InAlloca),
"Attributes 'byval' and 'inalloca' do not support unsized types!",
V);
}
} else {
Assert(!Attrs.hasAttribute(Idx, Attribute::ByVal),
"Attribute 'byval' only applies to parameters with pointer type!",
V);
}
}
// VerifyFunctionAttrs - Check parameter attributes against a function type.
// The value V is printed in error messages.
void Verifier::VerifyFunctionAttrs(FunctionType *FT, AttributeSet Attrs,
const Value *V) {
if (Attrs.isEmpty())
return;
bool SawNest = false;
bool SawReturned = false;
bool SawSRet = false;
for (unsigned i = 0, e = Attrs.getNumSlots(); i != e; ++i) {
unsigned Idx = Attrs.getSlotIndex(i);
Type *Ty;
if (Idx == 0)
Ty = FT->getReturnType();
else if (Idx-1 < FT->getNumParams())
Ty = FT->getParamType(Idx-1);
else
break; // VarArgs attributes, verified elsewhere.
VerifyParameterAttrs(Attrs, Idx, Ty, Idx == 0, V);
if (Idx == 0)
continue;
if (Attrs.hasAttribute(Idx, Attribute::Nest)) {
Assert(!SawNest, "More than one parameter has attribute nest!", V);
SawNest = true;
}
if (Attrs.hasAttribute(Idx, Attribute::Returned)) {
Assert(!SawReturned, "More than one parameter has attribute returned!",
V);
Assert(Ty->canLosslesslyBitCastTo(FT->getReturnType()),
"Incompatible "
"argument and return types for 'returned' attribute",
V);
SawReturned = true;
}
if (Attrs.hasAttribute(Idx, Attribute::StructRet)) {
Assert(!SawSRet, "Cannot have multiple 'sret' parameters!", V);
Assert(Idx == 1 || Idx == 2,
"Attribute 'sret' is not on first or second parameter!", V);
SawSRet = true;
}
if (Attrs.hasAttribute(Idx, Attribute::InAlloca)) {
Assert(Idx == FT->getNumParams(), "inalloca isn't on the last parameter!",
V);
}
}
if (!Attrs.hasAttributes(AttributeSet::FunctionIndex))
return;
VerifyAttributeTypes(Attrs, AttributeSet::FunctionIndex, true, V);
Assert(
!(Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::ReadNone) &&
Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::ReadOnly)),
"Attributes 'readnone and readonly' are incompatible!", V);
Assert(
!(Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::NoInline) &&
Attrs.hasAttribute(AttributeSet::FunctionIndex,
Attribute::AlwaysInline)),
"Attributes 'noinline and alwaysinline' are incompatible!", V);
if (Attrs.hasAttribute(AttributeSet::FunctionIndex,
Attribute::OptimizeNone)) {
Assert(Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::NoInline),
"Attribute 'optnone' requires 'noinline'!", V);
Assert(!Attrs.hasAttribute(AttributeSet::FunctionIndex,
Attribute::OptimizeForSize),
"Attributes 'optsize and optnone' are incompatible!", V);
Assert(!Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::MinSize),
"Attributes 'minsize and optnone' are incompatible!", V);
}
if (Attrs.hasAttribute(AttributeSet::FunctionIndex,
Attribute::JumpTable)) {
const GlobalValue *GV = cast<GlobalValue>(V);
Assert(GV->hasUnnamedAddr(),
"Attribute 'jumptable' requires 'unnamed_addr'", V);
}
}
void Verifier::VerifyFunctionMetadata(
const SmallVector<std::pair<unsigned, MDNode *>, 4> MDs) {
if (MDs.empty())
return;
for (unsigned i = 0; i < MDs.size(); i++) {
if (MDs[i].first == LLVMContext::MD_prof) {
MDNode *MD = MDs[i].second;
Assert(MD->getNumOperands() == 2,
"!prof annotations should have exactly 2 operands", MD);
// Check first operand.
Assert(MD->getOperand(0) != nullptr, "first operand should not be null",
MD);
Assert(isa<MDString>(MD->getOperand(0)),
"expected string with name of the !prof annotation", MD);
MDString *MDS = cast<MDString>(MD->getOperand(0));
StringRef ProfName = MDS->getString();
Assert(ProfName.equals("function_entry_count"),
"first operand should be 'function_entry_count'", MD);
// Check second operand.
Assert(MD->getOperand(1) != nullptr, "second operand should not be null",
MD);
Assert(isa<ConstantAsMetadata>(MD->getOperand(1)),
"expected integer argument to function_entry_count", MD);
}
}
}
void Verifier::VerifyConstantExprBitcastType(const ConstantExpr *CE) {
if (CE->getOpcode() != Instruction::BitCast)
return;
Assert(CastInst::castIsValid(Instruction::BitCast, CE->getOperand(0),
CE->getType()),
"Invalid bitcast", CE);
}
bool Verifier::VerifyAttributeCount(AttributeSet Attrs, unsigned Params) {
if (Attrs.getNumSlots() == 0)
return true;
unsigned LastSlot = Attrs.getNumSlots() - 1;
unsigned LastIndex = Attrs.getSlotIndex(LastSlot);
if (LastIndex <= Params
|| (LastIndex == AttributeSet::FunctionIndex
&& (LastSlot == 0 || Attrs.getSlotIndex(LastSlot - 1) <= Params)))
return true;
return false;
}
/// \brief Verify that statepoint intrinsic is well formed.
void Verifier::VerifyStatepoint(ImmutableCallSite CS) {
assert(CS.getCalledFunction() &&
CS.getCalledFunction()->getIntrinsicID() ==
Intrinsic::experimental_gc_statepoint);
const Instruction &CI = *CS.getInstruction();
Assert(!CS.doesNotAccessMemory() && !CS.onlyReadsMemory() &&
!CS.onlyAccessesArgMemory(),
"gc.statepoint must read and write all memory to preserve "
"reordering restrictions required by safepoint semantics",
&CI);
const Value *IDV = CS.getArgument(0);
Assert(isa<ConstantInt>(IDV), "gc.statepoint ID must be a constant integer",
&CI);
const Value *NumPatchBytesV = CS.getArgument(1);
Assert(isa<ConstantInt>(NumPatchBytesV),
"gc.statepoint number of patchable bytes must be a constant integer",
&CI);
const int64_t NumPatchBytes =
cast<ConstantInt>(NumPatchBytesV)->getSExtValue();
assert(isInt<32>(NumPatchBytes) && "NumPatchBytesV is an i32!");
Assert(NumPatchBytes >= 0, "gc.statepoint number of patchable bytes must be "
"positive",
&CI);
const Value *Target = CS.getArgument(2);
const PointerType *PT = dyn_cast<PointerType>(Target->getType());
Assert(PT && PT->getElementType()->isFunctionTy(),
"gc.statepoint callee must be of function pointer type", &CI, Target);
FunctionType *TargetFuncType = cast<FunctionType>(PT->getElementType());
if (NumPatchBytes)
Assert(isa<ConstantPointerNull>(Target->stripPointerCasts()),
"gc.statepoint must have null as call target if number of patchable "
"bytes is non zero",
&CI);
const Value *NumCallArgsV = CS.getArgument(3);
Assert(isa<ConstantInt>(NumCallArgsV),
"gc.statepoint number of arguments to underlying call "
"must be constant integer",
&CI);
const int NumCallArgs = cast<ConstantInt>(NumCallArgsV)->getZExtValue();
Assert(NumCallArgs >= 0,
"gc.statepoint number of arguments to underlying call "
"must be positive",
&CI);
const int NumParams = (int)TargetFuncType->getNumParams();
if (TargetFuncType->isVarArg()) {
Assert(NumCallArgs >= NumParams,
"gc.statepoint mismatch in number of vararg call args", &CI);
// TODO: Remove this limitation
Assert(TargetFuncType->getReturnType()->isVoidTy(),
"gc.statepoint doesn't support wrapping non-void "
"vararg functions yet",
&CI);
} else
Assert(NumCallArgs == NumParams,
"gc.statepoint mismatch in number of call args", &CI);
const Value *FlagsV = CS.getArgument(4);
Assert(isa<ConstantInt>(FlagsV),
"gc.statepoint flags must be constant integer", &CI);
const uint64_t Flags = cast<ConstantInt>(FlagsV)->getZExtValue();
Assert((Flags & ~(uint64_t)StatepointFlags::MaskAll) == 0,
"unknown flag used in gc.statepoint flags argument", &CI);
// Verify that the types of the call parameter arguments match
// the type of the wrapped callee.
for (int i = 0; i < NumParams; i++) {
Type *ParamType = TargetFuncType->getParamType(i);
Type *ArgType = CS.getArgument(5 + i)->getType();
Assert(ArgType == ParamType,
"gc.statepoint call argument does not match wrapped "
"function type",
&CI);
}
const int EndCallArgsInx = 4 + NumCallArgs;
const Value *NumTransitionArgsV = CS.getArgument(EndCallArgsInx+1);
Assert(isa<ConstantInt>(NumTransitionArgsV),
"gc.statepoint number of transition arguments "
"must be constant integer",
&CI);
const int NumTransitionArgs =
cast<ConstantInt>(NumTransitionArgsV)->getZExtValue();
Assert(NumTransitionArgs >= 0,
"gc.statepoint number of transition arguments must be positive", &CI);
const int EndTransitionArgsInx = EndCallArgsInx + 1 + NumTransitionArgs;
const Value *NumDeoptArgsV = CS.getArgument(EndTransitionArgsInx+1);
Assert(isa<ConstantInt>(NumDeoptArgsV),
"gc.statepoint number of deoptimization arguments "
"must be constant integer",
&CI);
const int NumDeoptArgs = cast<ConstantInt>(NumDeoptArgsV)->getZExtValue();
Assert(NumDeoptArgs >= 0, "gc.statepoint number of deoptimization arguments "
"must be positive",
&CI);
const int ExpectedNumArgs =
7 + NumCallArgs + NumTransitionArgs + NumDeoptArgs;
Assert(ExpectedNumArgs <= (int)CS.arg_size(),
"gc.statepoint too few arguments according to length fields", &CI);
// Check that the only uses of this gc.statepoint are gc.result or
// gc.relocate calls which are tied to this statepoint and thus part
// of the same statepoint sequence
for (const User *U : CI.users()) {
const CallInst *Call = dyn_cast<const CallInst>(U);
Assert(Call, "illegal use of statepoint token", &CI, U);
if (!Call) continue;
Assert(isGCRelocate(Call) || isGCResult(Call),
"gc.result or gc.relocate are the only value uses"
"of a gc.statepoint",
&CI, U);
if (isGCResult(Call)) {
Assert(Call->getArgOperand(0) == &CI,
"gc.result connected to wrong gc.statepoint", &CI, Call);
} else if (isGCRelocate(Call)) {
Assert(Call->getArgOperand(0) == &CI,
"gc.relocate connected to wrong gc.statepoint", &CI, Call);
}
}
// Note: It is legal for a single derived pointer to be listed multiple
// times. It's non-optimal, but it is legal. It can also happen after
// insertion if we strip a bitcast away.
// Note: It is really tempting to check that each base is relocated and
// that a derived pointer is never reused as a base pointer. This turns
// out to be problematic since optimizations run after safepoint insertion
// can recognize equality properties that the insertion logic doesn't know
// about. See example statepoint.ll in the verifier subdirectory
}
void Verifier::verifyFrameRecoverIndices() {
for (auto &Counts : FrameEscapeInfo) {
Function *F = Counts.first;
unsigned EscapedObjectCount = Counts.second.first;
unsigned MaxRecoveredIndex = Counts.second.second;
Assert(MaxRecoveredIndex <= EscapedObjectCount,
"all indices passed to llvm.localrecover must be less than the "
"number of arguments passed ot llvm.localescape in the parent "
"function",
F);
}
}
// visitFunction - Verify that a function is ok.
//
void Verifier::visitFunction(const Function &F) {
// Check function arguments.
FunctionType *FT = F.getFunctionType();
unsigned NumArgs = F.arg_size();
Assert(Context == &F.getContext(),
"Function context does not match Module context!", &F);
Assert(!F.hasCommonLinkage(), "Functions may not have common linkage", &F);
Assert(FT->getNumParams() == NumArgs,
"# formal arguments must match # of arguments for function type!", &F,
FT);
Assert(F.getReturnType()->isFirstClassType() ||
F.getReturnType()->isVoidTy() || F.getReturnType()->isStructTy(),
"Functions cannot return aggregate values!", &F);
Assert(!F.hasStructRetAttr() || F.getReturnType()->isVoidTy(),
"Invalid struct return type!", &F);
AttributeSet Attrs = F.getAttributes();
Assert(VerifyAttributeCount(Attrs, FT->getNumParams()),
"Attribute after last parameter!", &F);
// Check function attributes.
VerifyFunctionAttrs(FT, Attrs, &F);
// On function declarations/definitions, we do not support the builtin
// attribute. We do not check this in VerifyFunctionAttrs since that is
// checking for Attributes that can/can not ever be on functions.
Assert(!Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::Builtin),
"Attribute 'builtin' can only be applied to a callsite.", &F);
// Check that this function meets the restrictions on this calling convention.
// Sometimes varargs is used for perfectly forwarding thunks, so some of these
// restrictions can be lifted.
switch (F.getCallingConv()) {
default:
case CallingConv::C:
break;
case CallingConv::Fast:
case CallingConv::Cold:
case CallingConv::Intel_OCL_BI:
case CallingConv::PTX_Kernel:
case CallingConv::PTX_Device:
Assert(!F.isVarArg(), "Calling convention does not support varargs or "
"perfect forwarding!",
&F);
break;
}
bool isLLVMdotName = F.getName().size() >= 5 &&
F.getName().substr(0, 5) == "llvm.";
// Check that the argument values match the function type for this function...
unsigned i = 0;
for (Function::const_arg_iterator I = F.arg_begin(), E = F.arg_end(); I != E;
++I, ++i) {
Assert(I->getType() == FT->getParamType(i),
"Argument value does not match function argument type!", I,
FT->getParamType(i));
Assert(I->getType()->isFirstClassType(),
"Function arguments must have first-class types!", I);
if (!isLLVMdotName)
Assert(!I->getType()->isMetadataTy(),
"Function takes metadata but isn't an intrinsic", I, &F);
}
// Get the function metadata attachments.
SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
F.getAllMetadata(MDs);
assert(F.hasMetadata() != MDs.empty() && "Bit out-of-sync");
VerifyFunctionMetadata(MDs);
if (F.isMaterializable()) {
// Function has a body somewhere we can't see.
Assert(MDs.empty(), "unmaterialized function cannot have metadata", &F,
MDs.empty() ? nullptr : MDs.front().second);
} else if (F.isDeclaration()) {
Assert(F.hasExternalLinkage() || F.hasExternalWeakLinkage(),
"invalid linkage type for function declaration", &F);
Assert(MDs.empty(), "function without a body cannot have metadata", &F,
MDs.empty() ? nullptr : MDs.front().second);
Assert(!F.hasPersonalityFn(),
"Function declaration shouldn't have a personality routine", &F);
} else {
// Verify that this function (which has a body) is not named "llvm.*". It
// is not legal to define intrinsics.
Assert(!isLLVMdotName, "llvm intrinsics cannot be defined!", &F);
// Check the entry node
const BasicBlock *Entry = &F.getEntryBlock();
Assert(pred_empty(Entry),
"Entry block to function must not have predecessors!", Entry);
// The address of the entry block cannot be taken, unless it is dead.
if (Entry->hasAddressTaken()) {
Assert(!BlockAddress::lookup(Entry)->isConstantUsed(),
"blockaddress may not be used with the entry block!", Entry);
}
// Visit metadata attachments.
for (const auto &I : MDs)
visitMDNode(*I.second);
}
// If this function is actually an intrinsic, verify that it is only used in
// direct call/invokes, never having its "address taken".
if (F.getIntrinsicID()) {
const User *U;
if (F.hasAddressTaken(&U))
Assert(0, "Invalid user of intrinsic instruction!", U);
}
Assert(!F.hasDLLImportStorageClass() ||
(F.isDeclaration() && F.hasExternalLinkage()) ||
F.hasAvailableExternallyLinkage(),
"Function is marked as dllimport, but not external.", &F);
}
// verifyBasicBlock - Verify that a basic block is well formed...
//
void Verifier::visitBasicBlock(BasicBlock &BB) {
InstsInThisBlock.clear();
// Ensure that basic blocks have terminators!
Assert(BB.getTerminator(), "Basic Block does not have terminator!", &BB);
// Check constraints that this basic block imposes on all of the PHI nodes in
// it.
if (isa<PHINode>(BB.front())) {
SmallVector<BasicBlock*, 8> Preds(pred_begin(&BB), pred_end(&BB));
SmallVector<std::pair<BasicBlock*, Value*>, 8> Values;
std::sort(Preds.begin(), Preds.end());
PHINode *PN;
for (BasicBlock::iterator I = BB.begin(); (PN = dyn_cast<PHINode>(I));++I) {
// Ensure that PHI nodes have at least one entry!
Assert(PN->getNumIncomingValues() != 0,
"PHI nodes must have at least one entry. If the block is dead, "
"the PHI should be removed!",
PN);
Assert(PN->getNumIncomingValues() == Preds.size(),
"PHINode should have one entry for each predecessor of its "
"parent basic block!",
PN);
// Get and sort all incoming values in the PHI node...
Values.clear();
Values.reserve(PN->getNumIncomingValues());
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
Values.push_back(std::make_pair(PN->getIncomingBlock(i),
PN->getIncomingValue(i)));
std::sort(Values.begin(), Values.end());
for (unsigned i = 0, e = Values.size(); i != e; ++i) {
// Check to make sure that if there is more than one entry for a
// particular basic block in this PHI node, that the incoming values are
// all identical.
//
Assert(i == 0 || Values[i].first != Values[i - 1].first ||
Values[i].second == Values[i - 1].second,
"PHI node has multiple entries for the same basic block with "
"different incoming values!",
PN, Values[i].first, Values[i].second, Values[i - 1].second);
// Check to make sure that the predecessors and PHI node entries are
// matched up.
Assert(Values[i].first == Preds[i],
"PHI node entries do not match predecessors!", PN,
Values[i].first, Preds[i]);
}
}
}
// Check that all instructions have their parent pointers set up correctly.
for (auto &I : BB)
{
Assert(I.getParent() == &BB, "Instruction has bogus parent pointer!");
}
}
void Verifier::visitTerminatorInst(TerminatorInst &I) {
// Ensure that terminators only exist at the end of the basic block.
Assert(&I == I.getParent()->getTerminator(),
"Terminator found in the middle of a basic block!", I.getParent());
visitInstruction(I);
}
void Verifier::visitBranchInst(BranchInst &BI) {
if (BI.isConditional()) {
Assert(BI.getCondition()->getType()->isIntegerTy(1),
"Branch condition is not 'i1' type!", &BI, BI.getCondition());
}
visitTerminatorInst(BI);
}
void Verifier::visitReturnInst(ReturnInst &RI) {
Function *F = RI.getParent()->getParent();
unsigned N = RI.getNumOperands();
if (F->getReturnType()->isVoidTy())
Assert(N == 0,
"Found return instr that returns non-void in Function of void "
"return type!",
&RI, F->getReturnType());
else
Assert(N == 1 && F->getReturnType() == RI.getOperand(0)->getType(),
"Function return type does not match operand "
"type of return inst!",
&RI, F->getReturnType());
// Check to make sure that the return value has necessary properties for
// terminators...
visitTerminatorInst(RI);
}
void Verifier::visitSwitchInst(SwitchInst &SI) {
// Check to make sure that all of the constants in the switch instruction
// have the same type as the switched-on value.
Type *SwitchTy = SI.getCondition()->getType();
SmallPtrSet<ConstantInt*, 32> Constants;
for (SwitchInst::CaseIt i = SI.case_begin(), e = SI.case_end(); i != e; ++i) {
Assert(i.getCaseValue()->getType() == SwitchTy,
"Switch constants must all be same type as switch value!", &SI);
Assert(Constants.insert(i.getCaseValue()).second,
"Duplicate integer as switch case", &SI, i.getCaseValue());
}
visitTerminatorInst(SI);
}
void Verifier::visitIndirectBrInst(IndirectBrInst &BI) {
Assert(BI.getAddress()->getType()->isPointerTy(),
"Indirectbr operand must have pointer type!", &BI);
for (unsigned i = 0, e = BI.getNumDestinations(); i != e; ++i)
Assert(BI.getDestination(i)->getType()->isLabelTy(),
"Indirectbr destinations must all have pointer type!", &BI);
visitTerminatorInst(BI);
}
void Verifier::visitSelectInst(SelectInst &SI) {
Assert(!SelectInst::areInvalidOperands(SI.getOperand(0), SI.getOperand(1),
SI.getOperand(2)),
"Invalid operands for select instruction!", &SI);
Assert(SI.getTrueValue()->getType() == SI.getType(),
"Select values must have same type as select instruction!", &SI);
visitInstruction(SI);
}
/// visitUserOp1 - User defined operators shouldn't live beyond the lifetime of
/// a pass, if any exist, it's an error.
///
void Verifier::visitUserOp1(Instruction &I) {
Assert(0, "User-defined operators should not live outside of a pass!", &I);
}
void Verifier::visitTruncInst(TruncInst &I) {
// Get the source and destination types
Type *SrcTy = I.getOperand(0)->getType();
Type *DestTy = I.getType();
// Get the size of the types in bits, we'll need this later
unsigned SrcBitSize = SrcTy->getScalarSizeInBits();
unsigned DestBitSize = DestTy->getScalarSizeInBits();
Assert(SrcTy->isIntOrIntVectorTy(), "Trunc only operates on integer", &I);
Assert(DestTy->isIntOrIntVectorTy(), "Trunc only produces integer", &I);
Assert(SrcTy->isVectorTy() == DestTy->isVectorTy(),
"trunc source and destination must both be a vector or neither", &I);
Assert(SrcBitSize > DestBitSize, "DestTy too big for Trunc", &I);
visitInstruction(I);
}
void Verifier::visitZExtInst(ZExtInst &I) {
// Get the source and destination types
Type *SrcTy = I.getOperand(0)->getType();
Type *DestTy = I.getType();
// Get the size of the types in bits, we'll need this later
Assert(SrcTy->isIntOrIntVectorTy(), "ZExt only operates on integer", &I);
Assert(DestTy->isIntOrIntVectorTy(), "ZExt only produces an integer", &I);
Assert(SrcTy->isVectorTy() == DestTy->isVectorTy(),
"zext source and destination must both be a vector or neither", &I);
unsigned SrcBitSize = SrcTy->getScalarSizeInBits();
unsigned DestBitSize = DestTy->getScalarSizeInBits();
Assert(SrcBitSize < DestBitSize, "Type too small for ZExt", &I);
visitInstruction(I);
}
void Verifier::visitSExtInst(SExtInst &I) {
// Get the source and destination types
Type *SrcTy = I.getOperand(0)->getType();
Type *DestTy = I.getType();
// Get the size of the types in bits, we'll need this later
unsigned SrcBitSize = SrcTy->getScalarSizeInBits();
unsigned DestBitSize = DestTy->getScalarSizeInBits();
Assert(SrcTy->isIntOrIntVectorTy(), "SExt only operates on integer", &I);
Assert(DestTy->isIntOrIntVectorTy(), "SExt only produces an integer", &I);
Assert(SrcTy->isVectorTy() == DestTy->isVectorTy(),
"sext source and destination must both be a vector or neither", &I);
Assert(SrcBitSize < DestBitSize, "Type too small for SExt", &I);
visitInstruction(I);
}
void Verifier::visitFPTruncInst(FPTruncInst &I) {
// Get the source and destination types
Type *SrcTy = I.getOperand(0)->getType();
Type *DestTy = I.getType();
// Get the size of the types in bits, we'll need this later
unsigned SrcBitSize = SrcTy->getScalarSizeInBits();
unsigned DestBitSize = DestTy->getScalarSizeInBits();
Assert(SrcTy->isFPOrFPVectorTy(), "FPTrunc only operates on FP", &I);
Assert(DestTy->isFPOrFPVectorTy(), "FPTrunc only produces an FP", &I);
Assert(SrcTy->isVectorTy() == DestTy->isVectorTy(),
"fptrunc source and destination must both be a vector or neither", &I);
Assert(SrcBitSize > DestBitSize, "DestTy too big for FPTrunc", &I);
visitInstruction(I);
}
void Verifier::visitFPExtInst(FPExtInst &I) {
// Get the source and destination types
Type *SrcTy = I.getOperand(0)->getType();
Type *DestTy = I.getType();
// Get the size of the types in bits, we'll need this later
unsigned SrcBitSize = SrcTy->getScalarSizeInBits();
unsigned DestBitSize = DestTy->getScalarSizeInBits();
Assert(SrcTy->isFPOrFPVectorTy(), "FPExt only operates on FP", &I);
Assert(DestTy->isFPOrFPVectorTy(), "FPExt only produces an FP", &I);
Assert(SrcTy->isVectorTy() == DestTy->isVectorTy(),
"fpext source and destination must both be a vector or neither", &I);
Assert(SrcBitSize < DestBitSize, "DestTy too small for FPExt", &I);
visitInstruction(I);
}
void Verifier::visitUIToFPInst(UIToFPInst &I) {
// Get the source and destination types
Type *SrcTy = I.getOperand(0)->getType();
Type *DestTy = I.getType();
bool SrcVec = SrcTy->isVectorTy();
bool DstVec = DestTy->isVectorTy();
Assert(SrcVec == DstVec,
"UIToFP source and dest must both be vector or scalar", &I);
Assert(SrcTy->isIntOrIntVectorTy(),
"UIToFP source must be integer or integer vector", &I);
Assert(DestTy->isFPOrFPVectorTy(), "UIToFP result must be FP or FP vector",
&I);
if (SrcVec && DstVec)
Assert(cast<VectorType>(SrcTy)->getNumElements() ==
cast<VectorType>(DestTy)->getNumElements(),
"UIToFP source and dest vector length mismatch", &I);
visitInstruction(I);
}
void Verifier::visitSIToFPInst(SIToFPInst &I) {
// Get the source and destination types
Type *SrcTy = I.getOperand(0)->getType();
Type *DestTy = I.getType();
bool SrcVec = SrcTy->isVectorTy();
bool DstVec = DestTy->isVectorTy();
Assert(SrcVec == DstVec,
"SIToFP source and dest must both be vector or scalar", &I);
Assert(SrcTy->isIntOrIntVectorTy(),
"SIToFP source must be integer or integer vector", &I);
Assert(DestTy->isFPOrFPVectorTy(), "SIToFP result must be FP or FP vector",
&I);
if (SrcVec && DstVec)
Assert(cast<VectorType>(SrcTy)->getNumElements() ==
cast<VectorType>(DestTy)->getNumElements(),
"SIToFP source and dest vector length mismatch", &I);
visitInstruction(I);
}
void Verifier::visitFPToUIInst(FPToUIInst &I) {
// Get the source and destination types
Type *SrcTy = I.getOperand(0)->getType();
Type *DestTy = I.getType();
bool SrcVec = SrcTy->isVectorTy();
bool DstVec = DestTy->isVectorTy();
Assert(SrcVec == DstVec,
"FPToUI source and dest must both be vector or scalar", &I);
Assert(SrcTy->isFPOrFPVectorTy(), "FPToUI source must be FP or FP vector",
&I);
Assert(DestTy->isIntOrIntVectorTy(),
"FPToUI result must be integer or integer vector", &I);
if (SrcVec && DstVec)
Assert(cast<VectorType>(SrcTy)->getNumElements() ==
cast<VectorType>(DestTy)->getNumElements(),
"FPToUI source and dest vector length mismatch", &I);
visitInstruction(I);
}
void Verifier::visitFPToSIInst(FPToSIInst &I) {
// Get the source and destination types
Type *SrcTy = I.getOperand(0)->getType();
Type *DestTy = I.getType();
bool SrcVec = SrcTy->isVectorTy();
bool DstVec = DestTy->isVectorTy();
Assert(SrcVec == DstVec,
"FPToSI source and dest must both be vector or scalar", &I);
Assert(SrcTy->isFPOrFPVectorTy(), "FPToSI source must be FP or FP vector",
&I);
Assert(DestTy->isIntOrIntVectorTy(),
"FPToSI result must be integer or integer vector", &I);
if (SrcVec && DstVec)
Assert(cast<VectorType>(SrcTy)->getNumElements() ==
cast<VectorType>(DestTy)->getNumElements(),
"FPToSI source and dest vector length mismatch", &I);
visitInstruction(I);
}
void Verifier::visitPtrToIntInst(PtrToIntInst &I) {
// Get the source and destination types
Type *SrcTy = I.getOperand(0)->getType();
Type *DestTy = I.getType();
Assert(SrcTy->getScalarType()->isPointerTy(),
"PtrToInt source must be pointer", &I);
Assert(DestTy->getScalarType()->isIntegerTy(),
"PtrToInt result must be integral", &I);
Assert(SrcTy->isVectorTy() == DestTy->isVectorTy(), "PtrToInt type mismatch",
&I);
if (SrcTy->isVectorTy()) {
VectorType *VSrc = dyn_cast<VectorType>(SrcTy);
VectorType *VDest = dyn_cast<VectorType>(DestTy);
Assert(VSrc->getNumElements() == VDest->getNumElements(),
"PtrToInt Vector width mismatch", &I);
}
visitInstruction(I);
}
void Verifier::visitIntToPtrInst(IntToPtrInst &I) {
// Get the source and destination types
Type *SrcTy = I.getOperand(0)->getType();
Type *DestTy = I.getType();
Assert(SrcTy->getScalarType()->isIntegerTy(),
"IntToPtr source must be an integral", &I);
Assert(DestTy->getScalarType()->isPointerTy(),
"IntToPtr result must be a pointer", &I);
Assert(SrcTy->isVectorTy() == DestTy->isVectorTy(), "IntToPtr type mismatch",
&I);
if (SrcTy->isVectorTy()) {
VectorType *VSrc = dyn_cast<VectorType>(SrcTy);
VectorType *VDest = dyn_cast<VectorType>(DestTy);
Assert(VSrc->getNumElements() == VDest->getNumElements(),
"IntToPtr Vector width mismatch", &I);
}
visitInstruction(I);
}
void Verifier::visitBitCastInst(BitCastInst &I) {
Assert(
CastInst::castIsValid(Instruction::BitCast, I.getOperand(0), I.getType()),
"Invalid bitcast", &I);
visitInstruction(I);
}
void Verifier::visitAddrSpaceCastInst(AddrSpaceCastInst &I) {
Type *SrcTy = I.getOperand(0)->getType();
Type *DestTy = I.getType();
Assert(SrcTy->isPtrOrPtrVectorTy(), "AddrSpaceCast source must be a pointer",
&I);
Assert(DestTy->isPtrOrPtrVectorTy(), "AddrSpaceCast result must be a pointer",
&I);
Assert(SrcTy->getPointerAddressSpace() != DestTy->getPointerAddressSpace(),
"AddrSpaceCast must be between different address spaces", &I);
if (SrcTy->isVectorTy())
Assert(SrcTy->getVectorNumElements() == DestTy->getVectorNumElements(),
"AddrSpaceCast vector pointer number of elements mismatch", &I);
visitInstruction(I);
}
/// visitPHINode - Ensure that a PHI node is well formed.
///
void Verifier::visitPHINode(PHINode &PN) {
// Ensure that the PHI nodes are all grouped together at the top of the block.
// This can be tested by checking whether the instruction before this is
// either nonexistent (because this is begin()) or is a PHI node. If not,
// then there is some other instruction before a PHI.
Assert(&PN == &PN.getParent()->front() ||
isa<PHINode>(--BasicBlock::iterator(&PN)),
"PHI nodes not grouped at top of basic block!", &PN, PN.getParent());
// Check that all of the values of the PHI node have the same type as the
// result, and that the incoming blocks are really basic blocks.
for (Value *IncValue : PN.incoming_values()) {
Assert(PN.getType() == IncValue->getType(),
"PHI node operands are not the same type as the result!", &PN);
}
// All other PHI node constraints are checked in the visitBasicBlock method.
visitInstruction(PN);
}
void Verifier::VerifyCallSite(CallSite CS) {
Instruction *I = CS.getInstruction();
Assert(CS.getCalledValue()->getType()->isPointerTy(),
"Called function must be a pointer!", I);
PointerType *FPTy = cast<PointerType>(CS.getCalledValue()->getType());
Assert(FPTy->getElementType()->isFunctionTy(),
"Called function is not pointer to function type!", I);
Assert(FPTy->getElementType() == CS.getFunctionType(),
"Called function is not the same type as the call!", I);
FunctionType *FTy = CS.getFunctionType();
// Verify that the correct number of arguments are being passed
if (FTy->isVarArg())
Assert(CS.arg_size() >= FTy->getNumParams(),
"Called function requires more parameters than were provided!", I);
else
Assert(CS.arg_size() == FTy->getNumParams(),
"Incorrect number of arguments passed to called function!", I);
// Verify that all arguments to the call match the function type.
for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
Assert(CS.getArgument(i)->getType() == FTy->getParamType(i),
"Call parameter type does not match function signature!",
CS.getArgument(i), FTy->getParamType(i), I);
AttributeSet Attrs = CS.getAttributes();
Assert(VerifyAttributeCount(Attrs, CS.arg_size()),
"Attribute after last parameter!", I);
// Verify call attributes.
VerifyFunctionAttrs(FTy, Attrs, I);
// Conservatively check the inalloca argument.
// We have a bug if we can find that there is an underlying alloca without
// inalloca.
if (CS.hasInAllocaArgument()) {
Value *InAllocaArg = CS.getArgument(FTy->getNumParams() - 1);
if (auto AI = dyn_cast<AllocaInst>(InAllocaArg->stripInBoundsOffsets()))
Assert(AI->isUsedWithInAlloca(),
"inalloca argument for call has mismatched alloca", AI, I);
}
if (FTy->isVarArg()) {
// FIXME? is 'nest' even legal here?
bool SawNest = false;
bool SawReturned = false;
for (unsigned Idx = 1; Idx < 1 + FTy->getNumParams(); ++Idx) {
if (Attrs.hasAttribute(Idx, Attribute::Nest))
SawNest = true;
if (Attrs.hasAttribute(Idx, Attribute::Returned))
SawReturned = true;
}
// Check attributes on the varargs part.
for (unsigned Idx = 1 + FTy->getNumParams(); Idx <= CS.arg_size(); ++Idx) {
Type *Ty = CS.getArgument(Idx-1)->getType();
VerifyParameterAttrs(Attrs, Idx, Ty, false, I);
if (Attrs.hasAttribute(Idx, Attribute::Nest)) {
Assert(!SawNest, "More than one parameter has attribute nest!", I);
SawNest = true;
}
if (Attrs.hasAttribute(Idx, Attribute::Returned)) {
Assert(!SawReturned, "More than one parameter has attribute returned!",
I);
Assert(Ty->canLosslesslyBitCastTo(FTy->getReturnType()),
"Incompatible argument and return types for 'returned' "
"attribute",
I);
SawReturned = true;
}
Assert(!Attrs.hasAttribute(Idx, Attribute::StructRet),
"Attribute 'sret' cannot be used for vararg call arguments!", I);
if (Attrs.hasAttribute(Idx, Attribute::InAlloca))
Assert(Idx == CS.arg_size(), "inalloca isn't on the last argument!", I);
}
}
// Verify that there's no metadata unless it's a direct call to an intrinsic.
if (CS.getCalledFunction() == nullptr ||
!CS.getCalledFunction()->getName().startswith("llvm.")) {
for (FunctionType::param_iterator PI = FTy->param_begin(),
PE = FTy->param_end(); PI != PE; ++PI)
Assert(!(*PI)->isMetadataTy(),
"Function has metadata parameter but isn't an intrinsic", I);
}
if (Function *F = CS.getCalledFunction())
if (Intrinsic::ID ID = (Intrinsic::ID)F->getIntrinsicID())
visitIntrinsicCallSite(ID, CS);
visitInstruction(*I);
}
/// Two types are "congruent" if they are identical, or if they are both pointer
/// types with different pointee types and the same address space.
static bool isTypeCongruent(Type *L, Type *R) {
if (L == R)
return true;
PointerType *PL = dyn_cast<PointerType>(L);
PointerType *PR = dyn_cast<PointerType>(R);
if (!PL || !PR)
return false;
return PL->getAddressSpace() == PR->getAddressSpace();
}
static AttrBuilder getParameterABIAttributes(int I, AttributeSet Attrs) {
static const Attribute::AttrKind ABIAttrs[] = {
Attribute::StructRet, Attribute::ByVal, Attribute::InAlloca,
Attribute::InReg, Attribute::Returned};
AttrBuilder Copy;
for (auto AK : ABIAttrs) {
if (Attrs.hasAttribute(I + 1, AK))
Copy.addAttribute(AK);
}
if (Attrs.hasAttribute(I + 1, Attribute::Alignment))
Copy.addAlignmentAttr(Attrs.getParamAlignment(I + 1));
return Copy;
}
void Verifier::verifyMustTailCall(CallInst &CI) {
Assert(!CI.isInlineAsm(), "cannot use musttail call with inline asm", &CI);
// - The caller and callee prototypes must match. Pointer types of
// parameters or return types may differ in pointee type, but not
// address space.
Function *F = CI.getParent()->getParent();
FunctionType *CallerTy = F->getFunctionType();
FunctionType *CalleeTy = CI.getFunctionType();
Assert(CallerTy->getNumParams() == CalleeTy->getNumParams(),
"cannot guarantee tail call due to mismatched parameter counts", &CI);
Assert(CallerTy->isVarArg() == CalleeTy->isVarArg(),
"cannot guarantee tail call due to mismatched varargs", &CI);
Assert(isTypeCongruent(CallerTy->getReturnType(), CalleeTy->getReturnType()),
"cannot guarantee tail call due to mismatched return types", &CI);
for (int I = 0, E = CallerTy->getNumParams(); I != E; ++I) {
Assert(
isTypeCongruent(CallerTy->getParamType(I), CalleeTy->getParamType(I)),
"cannot guarantee tail call due to mismatched parameter types", &CI);
}
// - The calling conventions of the caller and callee must match.
Assert(F->getCallingConv() == CI.getCallingConv(),
"cannot guarantee tail call due to mismatched calling conv", &CI);
// - All ABI-impacting function attributes, such as sret, byval, inreg,
// returned, and inalloca, must match.
AttributeSet CallerAttrs = F->getAttributes();
AttributeSet CalleeAttrs = CI.getAttributes();
for (int I = 0, E = CallerTy->getNumParams(); I != E; ++I) {
AttrBuilder CallerABIAttrs = getParameterABIAttributes(I, CallerAttrs);
AttrBuilder CalleeABIAttrs = getParameterABIAttributes(I, CalleeAttrs);
Assert(CallerABIAttrs == CalleeABIAttrs,
"cannot guarantee tail call due to mismatched ABI impacting "
"function attributes",
&CI, CI.getOperand(I));
}
// - The call must immediately precede a :ref:`ret <i_ret>` instruction,
// or a pointer bitcast followed by a ret instruction.
// - The ret instruction must return the (possibly bitcasted) value
// produced by the call or void.
Value *RetVal = &CI;
Instruction *Next = CI.getNextNode();
// Handle the optional bitcast.
if (BitCastInst *BI = dyn_cast_or_null<BitCastInst>(Next)) {
Assert(BI->getOperand(0) == RetVal,
"bitcast following musttail call must use the call", BI);
RetVal = BI;
Next = BI->getNextNode();
}
// Check the return.
ReturnInst *Ret = dyn_cast_or_null<ReturnInst>(Next);
Assert(Ret, "musttail call must be precede a ret with an optional bitcast",
&CI);
Assert(!Ret->getReturnValue() || Ret->getReturnValue() == RetVal,
"musttail call result must be returned", Ret);
}
void Verifier::visitCallInst(CallInst &CI) {
VerifyCallSite(&CI);
if (CI.isMustTailCall())
verifyMustTailCall(CI);
}
void Verifier::visitInvokeInst(InvokeInst &II) {
VerifyCallSite(&II);
// Verify that there is a landingpad instruction as the first non-PHI
// instruction of the 'unwind' destination.
Assert(II.getUnwindDest()->isLandingPad(),
"The unwind destination does not have a landingpad instruction!", &II);
visitTerminatorInst(II);
}
/// visitBinaryOperator - Check that both arguments to the binary operator are
/// of the same type!
///
void Verifier::visitBinaryOperator(BinaryOperator &B) {
Assert(B.getOperand(0)->getType() == B.getOperand(1)->getType(),
"Both operands to a binary operator are not of the same type!", &B);
switch (B.getOpcode()) {
// Check that integer arithmetic operators are only used with
// integral operands.
case Instruction::Add:
case Instruction::Sub:
case Instruction::Mul:
case Instruction::SDiv:
case Instruction::UDiv:
case Instruction::SRem:
case Instruction::URem:
Assert(B.getType()->isIntOrIntVectorTy(),
"Integer arithmetic operators only work with integral types!", &B);
Assert(B.getType() == B.getOperand(0)->getType(),
"Integer arithmetic operators must have same type "
"for operands and result!",
&B);
break;
// Check that floating-point arithmetic operators are only used with
// floating-point operands.
case Instruction::FAdd:
case Instruction::FSub:
case Instruction::FMul:
case Instruction::FDiv:
case Instruction::FRem:
Assert(B.getType()->isFPOrFPVectorTy(),
"Floating-point arithmetic operators only work with "
"floating-point types!",
&B);
Assert(B.getType() == B.getOperand(0)->getType(),
"Floating-point arithmetic operators must have same type "
"for operands and result!",
&B);
break;
// Check that logical operators are only used with integral operands.
case Instruction::And:
case Instruction::Or:
case Instruction::Xor:
Assert(B.getType()->isIntOrIntVectorTy(),
"Logical operators only work with integral types!", &B);
Assert(B.getType() == B.getOperand(0)->getType(),
"Logical operators must have same type for operands and result!",
&B);
break;
case Instruction::Shl:
case Instruction::LShr:
case Instruction::AShr:
Assert(B.getType()->isIntOrIntVectorTy(),
"Shifts only work with integral types!", &B);
Assert(B.getType() == B.getOperand(0)->getType(),
"Shift return type must be same as operands!", &B);
break;
default:
llvm_unreachable("Unknown BinaryOperator opcode!");
}
visitInstruction(B);
}
void Verifier::visitICmpInst(ICmpInst &IC) {
// Check that the operands are the same type
Type *Op0Ty = IC.getOperand(0)->getType();
Type *Op1Ty = IC.getOperand(1)->getType();
Assert(Op0Ty == Op1Ty,
"Both operands to ICmp instruction are not of the same type!", &IC);
// Check that the operands are the right type
Assert(Op0Ty->isIntOrIntVectorTy() || Op0Ty->getScalarType()->isPointerTy(),
"Invalid operand types for ICmp instruction", &IC);
// Check that the predicate is valid.
Assert(IC.getPredicate() >= CmpInst::FIRST_ICMP_PREDICATE &&
IC.getPredicate() <= CmpInst::LAST_ICMP_PREDICATE,
"Invalid predicate in ICmp instruction!", &IC);
visitInstruction(IC);
}
void Verifier::visitFCmpInst(FCmpInst &FC) {
// Check that the operands are the same type
Type *Op0Ty = FC.getOperand(0)->getType();
Type *Op1Ty = FC.getOperand(1)->getType();
Assert(Op0Ty == Op1Ty,
"Both operands to FCmp instruction are not of the same type!", &FC);
// Check that the operands are the right type
Assert(Op0Ty->isFPOrFPVectorTy(),
"Invalid operand types for FCmp instruction", &FC);
// Check that the predicate is valid.
Assert(FC.getPredicate() >= CmpInst::FIRST_FCMP_PREDICATE &&
FC.getPredicate() <= CmpInst::LAST_FCMP_PREDICATE,
"Invalid predicate in FCmp instruction!", &FC);
visitInstruction(FC);
}
void Verifier::visitExtractElementInst(ExtractElementInst &EI) {
Assert(
ExtractElementInst::isValidOperands(EI.getOperand(0), EI.getOperand(1)),
"Invalid extractelement operands!", &EI);
visitInstruction(EI);
}
void Verifier::visitInsertElementInst(InsertElementInst &IE) {
Assert(InsertElementInst::isValidOperands(IE.getOperand(0), IE.getOperand(1),
IE.getOperand(2)),
"Invalid insertelement operands!", &IE);
visitInstruction(IE);
}
void Verifier::visitShuffleVectorInst(ShuffleVectorInst &SV) {
Assert(ShuffleVectorInst::isValidOperands(SV.getOperand(0), SV.getOperand(1),
SV.getOperand(2)),
"Invalid shufflevector operands!", &SV);
visitInstruction(SV);
}
void Verifier::visitGetElementPtrInst(GetElementPtrInst &GEP) {
Type *TargetTy = GEP.getPointerOperandType()->getScalarType();
Assert(isa<PointerType>(TargetTy),
"GEP base pointer is not a vector or a vector of pointers", &GEP);
Assert(GEP.getSourceElementType()->isSized(), "GEP into unsized type!", &GEP);
SmallVector<Value*, 16> Idxs(GEP.idx_begin(), GEP.idx_end());
Type *ElTy =
GetElementPtrInst::getIndexedType(GEP.getSourceElementType(), Idxs);
Assert(ElTy, "Invalid indices for GEP pointer type!", &GEP);
Assert(GEP.getType()->getScalarType()->isPointerTy() &&
GEP.getResultElementType() == ElTy,
"GEP is not of right type for indices!", &GEP, ElTy);
if (GEP.getType()->isVectorTy()) {
// Additional checks for vector GEPs.
unsigned GEPWidth = GEP.getType()->getVectorNumElements();
if (GEP.getPointerOperandType()->isVectorTy())
Assert(GEPWidth == GEP.getPointerOperandType()->getVectorNumElements(),
"Vector GEP result width doesn't match operand's", &GEP);
for (unsigned i = 0, e = Idxs.size(); i != e; ++i) {
Type *IndexTy = Idxs[i]->getType();
if (IndexTy->isVectorTy()) {
unsigned IndexWidth = IndexTy->getVectorNumElements();
Assert(IndexWidth == GEPWidth, "Invalid GEP index vector width", &GEP);
}
Assert(IndexTy->getScalarType()->isIntegerTy(),
"All GEP indices should be of integer type");
}
}
visitInstruction(GEP);
}
static bool isContiguous(const ConstantRange &A, const ConstantRange &B) {
return A.getUpper() == B.getLower() || A.getLower() == B.getUpper();
}
void Verifier::visitRangeMetadata(Instruction& I,
MDNode* Range, Type* Ty) {
assert(Range &&
Range == I.getMetadata(LLVMContext::MD_range) &&
"precondition violation");
unsigned NumOperands = Range->getNumOperands();
Assert(NumOperands % 2 == 0, "Unfinished range!", Range);
unsigned NumRanges = NumOperands / 2;
Assert(NumRanges >= 1, "It should have at least one range!", Range);
ConstantRange LastRange(1); // Dummy initial value
for (unsigned i = 0; i < NumRanges; ++i) {
ConstantInt *Low =
mdconst::dyn_extract<ConstantInt>(Range->getOperand(2 * i));
Assert(Low, "The lower limit must be an integer!", Low);
ConstantInt *High =
mdconst::dyn_extract<ConstantInt>(Range->getOperand(2 * i + 1));
Assert(High, "The upper limit must be an integer!", High);
Assert(High->getType() == Low->getType() && High->getType() == Ty,
"Range types must match instruction type!", &I);
APInt HighV = High->getValue();
APInt LowV = Low->getValue();
ConstantRange CurRange(LowV, HighV);
Assert(!CurRange.isEmptySet() && !CurRange.isFullSet(),
"Range must not be empty!", Range);
if (i != 0) {
Assert(CurRange.intersectWith(LastRange).isEmptySet(),
"Intervals are overlapping", Range);
Assert(LowV.sgt(LastRange.getLower()), "Intervals are not in order",
Range);
Assert(!isContiguous(CurRange, LastRange), "Intervals are contiguous",
Range);
}
LastRange = ConstantRange(LowV, HighV);
}
if (NumRanges > 2) {
APInt FirstLow =
mdconst::dyn_extract<ConstantInt>(Range->getOperand(0))->getValue();
APInt FirstHigh =
mdconst::dyn_extract<ConstantInt>(Range->getOperand(1))->getValue();
ConstantRange FirstRange(FirstLow, FirstHigh);
Assert(FirstRange.intersectWith(LastRange).isEmptySet(),
"Intervals are overlapping", Range);
Assert(!isContiguous(FirstRange, LastRange), "Intervals are contiguous",
Range);
}
}
void Verifier::visitLoadInst(LoadInst &LI) {
PointerType *PTy = dyn_cast<PointerType>(LI.getOperand(0)->getType());
Assert(PTy, "Load operand must be a pointer.", &LI);
Type *ElTy = LI.getType();
Assert(LI.getAlignment() <= Value::MaximumAlignment,
"huge alignment values are unsupported", &LI);
if (LI.isAtomic()) {
Assert(LI.getOrdering() != Release && LI.getOrdering() != AcquireRelease,
"Load cannot have Release ordering", &LI);
Assert(LI.getAlignment() != 0,
"Atomic load must specify explicit alignment", &LI);
if (!ElTy->isPointerTy()) {
Assert(ElTy->isIntegerTy(), "atomic load operand must have integer type!",
&LI, ElTy);
unsigned Size = ElTy->getPrimitiveSizeInBits();
Assert(Size >= 8 && !(Size & (Size - 1)),
"atomic load operand must be power-of-two byte-sized integer", &LI,
ElTy);
}
} else {
Assert(LI.getSynchScope() == CrossThread,
"Non-atomic load cannot have SynchronizationScope specified", &LI);
}
visitInstruction(LI);
}
void Verifier::visitStoreInst(StoreInst &SI) {
PointerType *PTy = dyn_cast<PointerType>(SI.getOperand(1)->getType());
Assert(PTy, "Store operand must be a pointer.", &SI);
Type *ElTy = PTy->getElementType();
Assert(ElTy == SI.getOperand(0)->getType(),
"Stored value type does not match pointer operand type!", &SI, ElTy);
Assert(SI.getAlignment() <= Value::MaximumAlignment,
"huge alignment values are unsupported", &SI);
if (SI.isAtomic()) {
Assert(SI.getOrdering() != Acquire && SI.getOrdering() != AcquireRelease,
"Store cannot have Acquire ordering", &SI);
Assert(SI.getAlignment() != 0,
"Atomic store must specify explicit alignment", &SI);
if (!ElTy->isPointerTy()) {
Assert(ElTy->isIntegerTy(),
"atomic store operand must have integer type!", &SI, ElTy);
unsigned Size = ElTy->getPrimitiveSizeInBits();
Assert(Size >= 8 && !(Size & (Size - 1)),
"atomic store operand must be power-of-two byte-sized integer",
&SI, ElTy);
}
} else {
Assert(SI.getSynchScope() == CrossThread,
"Non-atomic store cannot have SynchronizationScope specified", &SI);
}
visitInstruction(SI);
}
void Verifier::visitAllocaInst(AllocaInst &AI) {
SmallPtrSet<const Type*, 4> Visited;
PointerType *PTy = AI.getType();
Assert(PTy->getAddressSpace() == 0,
"Allocation instruction pointer not in the generic address space!",
&AI);
Assert(AI.getAllocatedType()->isSized(&Visited),
"Cannot allocate unsized type", &AI);
Assert(AI.getArraySize()->getType()->isIntegerTy(),
"Alloca array size must have integer type", &AI);
Assert(AI.getAlignment() <= Value::MaximumAlignment,
"huge alignment values are unsupported", &AI);
visitInstruction(AI);
}
void Verifier::visitAtomicCmpXchgInst(AtomicCmpXchgInst &CXI) {
// FIXME: more conditions???
Assert(CXI.getSuccessOrdering() != NotAtomic,
"cmpxchg instructions must be atomic.", &CXI);
Assert(CXI.getFailureOrdering() != NotAtomic,
"cmpxchg instructions must be atomic.", &CXI);
Assert(CXI.getSuccessOrdering() != Unordered,
"cmpxchg instructions cannot be unordered.", &CXI);
Assert(CXI.getFailureOrdering() != Unordered,
"cmpxchg instructions cannot be unordered.", &CXI);
Assert(CXI.getSuccessOrdering() >= CXI.getFailureOrdering(),
"cmpxchg instructions be at least as constrained on success as fail",
&CXI);
Assert(CXI.getFailureOrdering() != Release &&
CXI.getFailureOrdering() != AcquireRelease,
"cmpxchg failure ordering cannot include release semantics", &CXI);
PointerType *PTy = dyn_cast<PointerType>(CXI.getOperand(0)->getType());
Assert(PTy, "First cmpxchg operand must be a pointer.", &CXI);
Type *ElTy = PTy->getElementType();
Assert(ElTy->isIntegerTy(), "cmpxchg operand must have integer type!", &CXI,
ElTy);
unsigned Size = ElTy->getPrimitiveSizeInBits();
Assert(Size >= 8 && !(Size & (Size - 1)),
"cmpxchg operand must be power-of-two byte-sized integer", &CXI, ElTy);
Assert(ElTy == CXI.getOperand(1)->getType(),
"Expected value type does not match pointer operand type!", &CXI,
ElTy);
Assert(ElTy == CXI.getOperand(2)->getType(),
"Stored value type does not match pointer operand type!", &CXI, ElTy);
visitInstruction(CXI);
}
void Verifier::visitAtomicRMWInst(AtomicRMWInst &RMWI) {
Assert(RMWI.getOrdering() != NotAtomic,
"atomicrmw instructions must be atomic.", &RMWI);
Assert(RMWI.getOrdering() != Unordered,
"atomicrmw instructions cannot be unordered.", &RMWI);
PointerType *PTy = dyn_cast<PointerType>(RMWI.getOperand(0)->getType());
Assert(PTy, "First atomicrmw operand must be a pointer.", &RMWI);
Type *ElTy = PTy->getElementType();
Assert(ElTy->isIntegerTy(), "atomicrmw operand must have integer type!",
&RMWI, ElTy);
unsigned Size = ElTy->getPrimitiveSizeInBits();
Assert(Size >= 8 && !(Size & (Size - 1)),
"atomicrmw operand must be power-of-two byte-sized integer", &RMWI,
ElTy);
Assert(ElTy == RMWI.getOperand(1)->getType(),
"Argument value type does not match pointer operand type!", &RMWI,
ElTy);
Assert(AtomicRMWInst::FIRST_BINOP <= RMWI.getOperation() &&
RMWI.getOperation() <= AtomicRMWInst::LAST_BINOP,
"Invalid binary operation!", &RMWI);
visitInstruction(RMWI);
}
void Verifier::visitFenceInst(FenceInst &FI) {
const AtomicOrdering Ordering = FI.getOrdering();
Assert(Ordering == Acquire || Ordering == Release ||
Ordering == AcquireRelease || Ordering == SequentiallyConsistent,
"fence instructions may only have "
"acquire, release, acq_rel, or seq_cst ordering.",
&FI);
visitInstruction(FI);
}
void Verifier::visitExtractValueInst(ExtractValueInst &EVI) {
Assert(ExtractValueInst::getIndexedType(EVI.getAggregateOperand()->getType(),
EVI.getIndices()) == EVI.getType(),
"Invalid ExtractValueInst operands!", &EVI);
visitInstruction(EVI);
}
void Verifier::visitInsertValueInst(InsertValueInst &IVI) {
Assert(ExtractValueInst::getIndexedType(IVI.getAggregateOperand()->getType(),
IVI.getIndices()) ==
IVI.getOperand(1)->getType(),
"Invalid InsertValueInst operands!", &IVI);
visitInstruction(IVI);
}
void Verifier::visitLandingPadInst(LandingPadInst &LPI) {
BasicBlock *BB = LPI.getParent();
// The landingpad instruction is ill-formed if it doesn't have any clauses and
// isn't a cleanup.
Assert(LPI.getNumClauses() > 0 || LPI.isCleanup(),
"LandingPadInst needs at least one clause or to be a cleanup.", &LPI);
// The landingpad instruction defines its parent as a landing pad block. The
// landing pad block may be branched to only by the unwind edge of an invoke.
for (pred_iterator I = pred_begin(BB), E = pred_end(BB); I != E; ++I) {
const InvokeInst *II = dyn_cast<InvokeInst>((*I)->getTerminator());
Assert(II && II->getUnwindDest() == BB && II->getNormalDest() != BB,
"Block containing LandingPadInst must be jumped to "
"only by the unwind edge of an invoke.",
&LPI);
}
Function *F = LPI.getParent()->getParent();
Assert(F->hasPersonalityFn(),
"LandingPadInst needs to be in a function with a personality.", &LPI);
// The landingpad instruction must be the first non-PHI instruction in the
// block.
Assert(LPI.getParent()->getLandingPadInst() == &LPI,
"LandingPadInst not the first non-PHI instruction in the block.",
&LPI);
for (unsigned i = 0, e = LPI.getNumClauses(); i < e; ++i) {
Constant *Clause = LPI.getClause(i);
if (LPI.isCatch(i)) {
Assert(isa<PointerType>(Clause->getType()),
"Catch operand does not have pointer type!", &LPI);
} else {
Assert(LPI.isFilter(i), "Clause is neither catch nor filter!", &LPI);
Assert(isa<ConstantArray>(Clause) || isa<ConstantAggregateZero>(Clause),
"Filter operand is not an array of constants!", &LPI);
}
}
visitInstruction(LPI);
}
void Verifier::verifyDominatesUse(Instruction &I, unsigned i) {
Instruction *Op = cast<Instruction>(I.getOperand(i));
// If the we have an invalid invoke, don't try to compute the dominance.
// We already reject it in the invoke specific checks and the dominance
// computation doesn't handle multiple edges.
if (InvokeInst *II = dyn_cast<InvokeInst>(Op)) {
if (II->getNormalDest() == II->getUnwindDest())
return;
}
const Use &U = I.getOperandUse(i);
Assert(InstsInThisBlock.count(Op) || DT.dominates(Op, U),
"Instruction does not dominate all uses!", Op, &I);
}
/// verifyInstruction - Verify that an instruction is well formed.
///
void Verifier::visitInstruction(Instruction &I) {
BasicBlock *BB = I.getParent();
Assert(BB, "Instruction not embedded in basic block!", &I);
if (!isa<PHINode>(I)) { // Check that non-phi nodes are not self referential
for (User *U : I.users()) {
Assert(U != (User *)&I || !DT.isReachableFromEntry(BB),
"Only PHI nodes may reference their own value!", &I);
}
}
// Check that void typed values don't have names
Assert(!I.getType()->isVoidTy() || !I.hasName(),
"Instruction has a name, but provides a void value!", &I);
// Check that the return value of the instruction is either void or a legal
// value type.
Assert(I.getType()->isVoidTy() || I.getType()->isFirstClassType(),
"Instruction returns a non-scalar type!", &I);
// Check that the instruction doesn't produce metadata. Calls are already
// checked against the callee type.
Assert(!I.getType()->isMetadataTy() || isa<CallInst>(I) || isa<InvokeInst>(I),
"Invalid use of metadata!", &I);
// Check that all uses of the instruction, if they are instructions
// themselves, actually have parent basic blocks. If the use is not an
// instruction, it is an error!
for (Use &U : I.uses()) {
if (Instruction *Used = dyn_cast<Instruction>(U.getUser()))
Assert(Used->getParent() != nullptr,
"Instruction referencing"
" instruction not embedded in a basic block!",
&I, Used);
else {
CheckFailed("Use of instruction is not an instruction!", U);
return;
}
}
for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i) {
Assert(I.getOperand(i) != nullptr, "Instruction has null operand!", &I);
// Check to make sure that only first-class-values are operands to
// instructions.
if (!I.getOperand(i)->getType()->isFirstClassType()) {
Assert(0, "Instruction operands must be first-class values!", &I);
}
if (Function *F = dyn_cast<Function>(I.getOperand(i))) {
// Check to make sure that the "address of" an intrinsic function is never
// taken.
Assert(
!F->isIntrinsic() ||
i == (isa<CallInst>(I) ? e - 1 : isa<InvokeInst>(I) ? e - 3 : 0),
"Cannot take the address of an intrinsic!", &I);
Assert(
!F->isIntrinsic() || isa<CallInst>(I) ||
F->getIntrinsicID() == Intrinsic::donothing ||
F->getIntrinsicID() == Intrinsic::experimental_patchpoint_void ||
F->getIntrinsicID() == Intrinsic::experimental_patchpoint_i64 ||
F->getIntrinsicID() == Intrinsic::experimental_gc_statepoint,
"Cannot invoke an intrinsinc other than"
" donothing or patchpoint",
&I);
Assert(F->getParent() == M, "Referencing function in another module!",
&I);
} else if (BasicBlock *OpBB = dyn_cast<BasicBlock>(I.getOperand(i))) {
Assert(OpBB->getParent() == BB->getParent(),
"Referring to a basic block in another function!", &I);
} else if (Argument *OpArg = dyn_cast<Argument>(I.getOperand(i))) {
Assert(OpArg->getParent() == BB->getParent(),
"Referring to an argument in another function!", &I);
} else if (GlobalValue *GV = dyn_cast<GlobalValue>(I.getOperand(i))) {
Assert(GV->getParent() == M, "Referencing global in another module!", &I);
} else if (isa<Instruction>(I.getOperand(i))) {
verifyDominatesUse(I, i);
} else if (isa<InlineAsm>(I.getOperand(i))) {
Assert((i + 1 == e && isa<CallInst>(I)) ||
(i + 3 == e && isa<InvokeInst>(I)),
"Cannot take the address of an inline asm!", &I);
} else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(I.getOperand(i))) {
if (CE->getType()->isPtrOrPtrVectorTy()) {
// If we have a ConstantExpr pointer, we need to see if it came from an
// illegal bitcast (inttoptr <constant int> )
SmallVector<const ConstantExpr *, 4> Stack;
SmallPtrSet<const ConstantExpr *, 4> Visited;
Stack.push_back(CE);
while (!Stack.empty()) {
const ConstantExpr *V = Stack.pop_back_val();
if (!Visited.insert(V).second)
continue;
VerifyConstantExprBitcastType(V);
for (unsigned I = 0, N = V->getNumOperands(); I != N; ++I) {
if (ConstantExpr *Op = dyn_cast<ConstantExpr>(V->getOperand(I)))
Stack.push_back(Op);
}
}
}
}
}
if (MDNode *MD = I.getMetadata(LLVMContext::MD_fpmath)) {
Assert(I.getType()->isFPOrFPVectorTy(),
"fpmath requires a floating point result!", &I);
Assert(MD->getNumOperands() == 1, "fpmath takes one operand!", &I);
if (ConstantFP *CFP0 =
mdconst::dyn_extract_or_null<ConstantFP>(MD->getOperand(0))) {
APFloat Accuracy = CFP0->getValueAPF();
Assert(Accuracy.isFiniteNonZero() && !Accuracy.isNegative(),
"fpmath accuracy not a positive number!", &I);
} else {
Assert(false, "invalid fpmath accuracy!", &I);
}
}
if (MDNode *Range = I.getMetadata(LLVMContext::MD_range)) {
Assert(isa<LoadInst>(I) || isa<CallInst>(I) || isa<InvokeInst>(I),
"Ranges are only for loads, calls and invokes!", &I);
visitRangeMetadata(I, Range, I.getType());
}
if (I.getMetadata(LLVMContext::MD_nonnull)) {
Assert(I.getType()->isPointerTy(), "nonnull applies only to pointer types",
&I);
Assert(isa<LoadInst>(I),
"nonnull applies only to load instructions, use attributes"
" for calls or invokes",
&I);
}
if (MDNode *N = I.getDebugLoc().getAsMDNode()) {
Assert(isa<DILocation>(N), "invalid !dbg metadata attachment", &I, N);
visitMDNode(*N);
}
InstsInThisBlock.insert(&I);
}
/// VerifyIntrinsicType - Verify that the specified type (which comes from an
/// intrinsic argument or return value) matches the type constraints specified
/// by the .td file (e.g. an "any integer" argument really is an integer).
///
/// This return true on error but does not print a message.
bool Verifier::VerifyIntrinsicType(Type *Ty,
ArrayRef<Intrinsic::IITDescriptor> &Infos,
SmallVectorImpl<Type*> &ArgTys) {
using namespace Intrinsic;
// If we ran out of descriptors, there are too many arguments.
if (Infos.empty()) return true;
IITDescriptor D = Infos.front();
Infos = Infos.slice(1);
switch (D.Kind) {
case IITDescriptor::Void: return !Ty->isVoidTy();
case IITDescriptor::VarArg: return true;
case IITDescriptor::MMX: return !Ty->isX86_MMXTy();
case IITDescriptor::Metadata: return !Ty->isMetadataTy();
case IITDescriptor::Half: return !Ty->isHalfTy();
case IITDescriptor::Float: return !Ty->isFloatTy();
case IITDescriptor::Double: return !Ty->isDoubleTy();
case IITDescriptor::Integer: return !Ty->isIntegerTy(D.Integer_Width);
case IITDescriptor::Vector: {
VectorType *VT = dyn_cast<VectorType>(Ty);
return !VT || VT->getNumElements() != D.Vector_Width ||
VerifyIntrinsicType(VT->getElementType(), Infos, ArgTys);
}
case IITDescriptor::Pointer: {
PointerType *PT = dyn_cast<PointerType>(Ty);
return !PT || PT->getAddressSpace() != D.Pointer_AddressSpace ||
VerifyIntrinsicType(PT->getElementType(), Infos, ArgTys);
}
case IITDescriptor::Struct: {
StructType *ST = dyn_cast<StructType>(Ty);
if (!ST || ST->getNumElements() != D.Struct_NumElements)
return true;
for (unsigned i = 0, e = D.Struct_NumElements; i != e; ++i)
if (VerifyIntrinsicType(ST->getElementType(i), Infos, ArgTys))
return true;
return false;
}
case IITDescriptor::Argument:
// Two cases here - If this is the second occurrence of an argument, verify
// that the later instance matches the previous instance.
if (D.getArgumentNumber() < ArgTys.size())
return Ty != ArgTys[D.getArgumentNumber()];
// Otherwise, if this is the first instance of an argument, record it and
// verify the "Any" kind.
assert(D.getArgumentNumber() == ArgTys.size() && "Table consistency error");
ArgTys.push_back(Ty);
switch (D.getArgumentKind()) {
case IITDescriptor::AK_Any: return false; // Success
case IITDescriptor::AK_AnyInteger: return !Ty->isIntOrIntVectorTy();
case IITDescriptor::AK_AnyFloat: return !Ty->isFPOrFPVectorTy();
case IITDescriptor::AK_AnyVector: return !isa<VectorType>(Ty);
case IITDescriptor::AK_AnyPointer: return !isa<PointerType>(Ty);
}
llvm_unreachable("all argument kinds not covered");
case IITDescriptor::ExtendArgument: {
// This may only be used when referring to a previous vector argument.
if (D.getArgumentNumber() >= ArgTys.size())
return true;
Type *NewTy = ArgTys[D.getArgumentNumber()];
if (VectorType *VTy = dyn_cast<VectorType>(NewTy))
NewTy = VectorType::getExtendedElementVectorType(VTy);
else if (IntegerType *ITy = dyn_cast<IntegerType>(NewTy))
NewTy = IntegerType::get(ITy->getContext(), 2 * ITy->getBitWidth());
else
return true;
return Ty != NewTy;
}
case IITDescriptor::TruncArgument: {
// This may only be used when referring to a previous vector argument.
if (D.getArgumentNumber() >= ArgTys.size())
return true;
Type *NewTy = ArgTys[D.getArgumentNumber()];
if (VectorType *VTy = dyn_cast<VectorType>(NewTy))
NewTy = VectorType::getTruncatedElementVectorType(VTy);
else if (IntegerType *ITy = dyn_cast<IntegerType>(NewTy))
NewTy = IntegerType::get(ITy->getContext(), ITy->getBitWidth() / 2);
else
return true;
return Ty != NewTy;
}
case IITDescriptor::HalfVecArgument:
// This may only be used when referring to a previous vector argument.
return D.getArgumentNumber() >= ArgTys.size() ||
!isa<VectorType>(ArgTys[D.getArgumentNumber()]) ||
VectorType::getHalfElementsVectorType(
cast<VectorType>(ArgTys[D.getArgumentNumber()])) != Ty;
case IITDescriptor::SameVecWidthArgument: {
if (D.getArgumentNumber() >= ArgTys.size())
return true;
VectorType * ReferenceType =
dyn_cast<VectorType>(ArgTys[D.getArgumentNumber()]);
VectorType *ThisArgType = dyn_cast<VectorType>(Ty);
if (!ThisArgType || !ReferenceType ||
(ReferenceType->getVectorNumElements() !=
ThisArgType->getVectorNumElements()))
return true;
return VerifyIntrinsicType(ThisArgType->getVectorElementType(),
Infos, ArgTys);
}
case IITDescriptor::PtrToArgument: {
if (D.getArgumentNumber() >= ArgTys.size())
return true;
Type * ReferenceType = ArgTys[D.getArgumentNumber()];
PointerType *ThisArgType = dyn_cast<PointerType>(Ty);
return (!ThisArgType || ThisArgType->getElementType() != ReferenceType);
}
case IITDescriptor::VecOfPtrsToElt: {
if (D.getArgumentNumber() >= ArgTys.size())
return true;
VectorType * ReferenceType =
dyn_cast<VectorType> (ArgTys[D.getArgumentNumber()]);
VectorType *ThisArgVecTy = dyn_cast<VectorType>(Ty);
if (!ThisArgVecTy || !ReferenceType ||
(ReferenceType->getVectorNumElements() !=
ThisArgVecTy->getVectorNumElements()))
return true;
PointerType *ThisArgEltTy =
dyn_cast<PointerType>(ThisArgVecTy->getVectorElementType());
if (!ThisArgEltTy)
return true;
return ThisArgEltTy->getElementType() !=
ReferenceType->getVectorElementType();
}
}
llvm_unreachable("unhandled");
}
/// \brief Verify if the intrinsic has variable arguments.
/// This method is intended to be called after all the fixed arguments have been
/// verified first.
///
/// This method returns true on error and does not print an error message.
bool
Verifier::VerifyIntrinsicIsVarArg(bool isVarArg,
ArrayRef<Intrinsic::IITDescriptor> &Infos) {
using namespace Intrinsic;
// If there are no descriptors left, then it can't be a vararg.
if (Infos.empty())
return isVarArg;
// There should be only one descriptor remaining at this point.
if (Infos.size() != 1)
return true;
// Check and verify the descriptor.
IITDescriptor D = Infos.front();
Infos = Infos.slice(1);
if (D.Kind == IITDescriptor::VarArg)
return !isVarArg;
return true;
}
/// Allow intrinsics to be verified in different ways.
void Verifier::visitIntrinsicCallSite(Intrinsic::ID ID, CallSite CS) {
Function *IF = CS.getCalledFunction();
Assert(IF->isDeclaration(), "Intrinsic functions should never be defined!",
IF);
// Verify that the intrinsic prototype lines up with what the .td files
// describe.
FunctionType *IFTy = IF->getFunctionType();
bool IsVarArg = IFTy->isVarArg();
SmallVector<Intrinsic::IITDescriptor, 8> Table;
getIntrinsicInfoTableEntries(ID, Table);
ArrayRef<Intrinsic::IITDescriptor> TableRef = Table;
SmallVector<Type *, 4> ArgTys;
Assert(!VerifyIntrinsicType(IFTy->getReturnType(), TableRef, ArgTys),
"Intrinsic has incorrect return type!", IF);
for (unsigned i = 0, e = IFTy->getNumParams(); i != e; ++i)
Assert(!VerifyIntrinsicType(IFTy->getParamType(i), TableRef, ArgTys),
"Intrinsic has incorrect argument type!", IF);
// Verify if the intrinsic call matches the vararg property.
if (IsVarArg)
Assert(!VerifyIntrinsicIsVarArg(IsVarArg, TableRef),
"Intrinsic was not defined with variable arguments!", IF);
else
Assert(!VerifyIntrinsicIsVarArg(IsVarArg, TableRef),
"Callsite was not defined with variable arguments!", IF);
// All descriptors should be absorbed by now.
Assert(TableRef.empty(), "Intrinsic has too few arguments!", IF);
// Now that we have the intrinsic ID and the actual argument types (and we
// know they are legal for the intrinsic!) get the intrinsic name through the
// usual means. This allows us to verify the mangling of argument types into
// the name.
const std::string ExpectedName = Intrinsic::getName(ID, ArgTys);
Assert(ExpectedName == IF->getName(),
"Intrinsic name not mangled correctly for type arguments! "
"Should be: " +
ExpectedName,
IF);
// If the intrinsic takes MDNode arguments, verify that they are either global
// or are local to *this* function.
for (Value *V : CS.args())
if (auto *MD = dyn_cast<MetadataAsValue>(V))
visitMetadataAsValue(*MD, CS.getCaller());
switch (ID) {
default:
break;
case Intrinsic::ctlz: // llvm.ctlz
case Intrinsic::cttz: // llvm.cttz
Assert(isa<ConstantInt>(CS.getArgOperand(1)),
"is_zero_undef argument of bit counting intrinsics must be a "
"constant int",
CS);
break;
case Intrinsic::dbg_declare: // llvm.dbg.declare
Assert(isa<MetadataAsValue>(CS.getArgOperand(0)),
"invalid llvm.dbg.declare intrinsic call 1", CS);
visitDbgIntrinsic("declare", cast<DbgDeclareInst>(*CS.getInstruction()));
break;
case Intrinsic::dbg_value: // llvm.dbg.value
visitDbgIntrinsic("value", cast<DbgValueInst>(*CS.getInstruction()));
break;
case Intrinsic::memcpy:
case Intrinsic::memmove:
case Intrinsic::memset: {
ConstantInt *AlignCI = dyn_cast<ConstantInt>(CS.getArgOperand(3));
Assert(AlignCI,
"alignment argument of memory intrinsics must be a constant int",
CS);
const APInt &AlignVal = AlignCI->getValue();
Assert(AlignCI->isZero() || AlignVal.isPowerOf2(),
"alignment argument of memory intrinsics must be a power of 2", CS);
Assert(isa<ConstantInt>(CS.getArgOperand(4)),
"isvolatile argument of memory intrinsics must be a constant int",
CS);
break;
}
case Intrinsic::gcroot:
case Intrinsic::gcwrite:
case Intrinsic::gcread:
if (ID == Intrinsic::gcroot) {
AllocaInst *AI =
dyn_cast<AllocaInst>(CS.getArgOperand(0)->stripPointerCasts());
Assert(AI, "llvm.gcroot parameter #1 must be an alloca.", CS);
Assert(isa<Constant>(CS.getArgOperand(1)),
"llvm.gcroot parameter #2 must be a constant.", CS);
if (!AI->getAllocatedType()->isPointerTy()) {
Assert(!isa<ConstantPointerNull>(CS.getArgOperand(1)),
"llvm.gcroot parameter #1 must either be a pointer alloca, "
"or argument #2 must be a non-null constant.",
CS);
}
}
Assert(CS.getParent()->getParent()->hasGC(),
"Enclosing function does not use GC.", CS);
break;
case Intrinsic::init_trampoline:
Assert(isa<Function>(CS.getArgOperand(1)->stripPointerCasts()),
"llvm.init_trampoline parameter #2 must resolve to a function.",
CS);
break;
case Intrinsic::prefetch:
Assert(isa<ConstantInt>(CS.getArgOperand(1)) &&
isa<ConstantInt>(CS.getArgOperand(2)) &&
cast<ConstantInt>(CS.getArgOperand(1))->getZExtValue() < 2 &&
cast<ConstantInt>(CS.getArgOperand(2))->getZExtValue() < 4,
"invalid arguments to llvm.prefetch", CS);
break;
case Intrinsic::stackprotector:
Assert(isa<AllocaInst>(CS.getArgOperand(1)->stripPointerCasts()),
"llvm.stackprotector parameter #2 must resolve to an alloca.", CS);
break;
case Intrinsic::lifetime_start:
case Intrinsic::lifetime_end:
case Intrinsic::invariant_start:
Assert(isa<ConstantInt>(CS.getArgOperand(0)),
"size argument of memory use markers must be a constant integer",
CS);
break;
case Intrinsic::invariant_end:
Assert(isa<ConstantInt>(CS.getArgOperand(1)),
"llvm.invariant.end parameter #2 must be a constant integer", CS);
break;
case Intrinsic::localescape: {
BasicBlock *BB = CS.getParent();
Assert(BB == &BB->getParent()->front(),
"llvm.localescape used outside of entry block", CS);
Assert(!SawFrameEscape,
"multiple calls to llvm.localescape in one function", CS);
for (Value *Arg : CS.args()) {
if (isa<ConstantPointerNull>(Arg))
continue; // Null values are allowed as placeholders.
auto *AI = dyn_cast<AllocaInst>(Arg->stripPointerCasts());
Assert(AI && AI->isStaticAlloca(),
"llvm.localescape only accepts static allocas", CS);
}
FrameEscapeInfo[BB->getParent()].first = CS.getNumArgOperands();
SawFrameEscape = true;
break;
}
case Intrinsic::localrecover: {
Value *FnArg = CS.getArgOperand(0)->stripPointerCasts();
Function *Fn = dyn_cast<Function>(FnArg);
Assert(Fn && !Fn->isDeclaration(),
"llvm.localrecover first "
"argument must be function defined in this module",
CS);
auto *IdxArg = dyn_cast<ConstantInt>(CS.getArgOperand(2));
Assert(IdxArg, "idx argument of llvm.localrecover must be a constant int",
CS);
auto &Entry = FrameEscapeInfo[Fn];
Entry.second = unsigned(
std::max(uint64_t(Entry.second), IdxArg->getLimitedValue(~0U) + 1));
break;
}
case Intrinsic::experimental_gc_statepoint:
Assert(!CS.isInlineAsm(),
"gc.statepoint support for inline assembly unimplemented", CS);
Assert(CS.getParent()->getParent()->hasGC(),
"Enclosing function does not use GC.", CS);
VerifyStatepoint(CS);
break;
case Intrinsic::experimental_gc_result_int:
case Intrinsic::experimental_gc_result_float:
case Intrinsic::experimental_gc_result_ptr:
case Intrinsic::experimental_gc_result: {
Assert(CS.getParent()->getParent()->hasGC(),
"Enclosing function does not use GC.", CS);
// Are we tied to a statepoint properly?
CallSite StatepointCS(CS.getArgOperand(0));
const Function *StatepointFn =
StatepointCS.getInstruction() ? StatepointCS.getCalledFunction() : nullptr;
Assert(StatepointFn && StatepointFn->isDeclaration() &&
StatepointFn->getIntrinsicID() ==
Intrinsic::experimental_gc_statepoint,
"gc.result operand #1 must be from a statepoint", CS,
CS.getArgOperand(0));
// Assert that result type matches wrapped callee.
const Value *Target = StatepointCS.getArgument(2);
const PointerType *PT = cast<PointerType>(Target->getType());
const FunctionType *TargetFuncType =
cast<FunctionType>(PT->getElementType());
Assert(CS.getType() == TargetFuncType->getReturnType(),
"gc.result result type does not match wrapped callee", CS);
break;
}
case Intrinsic::experimental_gc_relocate: {
Assert(CS.getNumArgOperands() == 3, "wrong number of arguments", CS);
// Check that this relocate is correctly tied to the statepoint
// This is case for relocate on the unwinding path of an invoke statepoint
if (ExtractValueInst *ExtractValue =
dyn_cast<ExtractValueInst>(CS.getArgOperand(0))) {
Assert(isa<LandingPadInst>(ExtractValue->getAggregateOperand()),
"gc relocate on unwind path incorrectly linked to the statepoint",
CS);
const BasicBlock *InvokeBB =
ExtractValue->getParent()->getUniquePredecessor();
// Landingpad relocates should have only one predecessor with invoke
// statepoint terminator
Assert(InvokeBB, "safepoints should have unique landingpads",
ExtractValue->getParent());
Assert(InvokeBB->getTerminator(), "safepoint block should be well formed",
InvokeBB);
Assert(isStatepoint(InvokeBB->getTerminator()),
"gc relocate should be linked to a statepoint", InvokeBB);
}
else {
// In all other cases relocate should be tied to the statepoint directly.
// This covers relocates on a normal return path of invoke statepoint and
// relocates of a call statepoint
auto Token = CS.getArgOperand(0);
Assert(isa<Instruction>(Token) && isStatepoint(cast<Instruction>(Token)),
"gc relocate is incorrectly tied to the statepoint", CS, Token);
}
// Verify rest of the relocate arguments
GCRelocateOperands Ops(CS);
ImmutableCallSite StatepointCS(Ops.getStatepoint());
// Both the base and derived must be piped through the safepoint
Value* Base = CS.getArgOperand(1);
Assert(isa<ConstantInt>(Base),
"gc.relocate operand #2 must be integer offset", CS);
Value* Derived = CS.getArgOperand(2);
Assert(isa<ConstantInt>(Derived),
"gc.relocate operand #3 must be integer offset", CS);
const int BaseIndex = cast<ConstantInt>(Base)->getZExtValue();
const int DerivedIndex = cast<ConstantInt>(Derived)->getZExtValue();
// Check the bounds
Assert(0 <= BaseIndex && BaseIndex < (int)StatepointCS.arg_size(),
"gc.relocate: statepoint base index out of bounds", CS);
Assert(0 <= DerivedIndex && DerivedIndex < (int)StatepointCS.arg_size(),
"gc.relocate: statepoint derived index out of bounds", CS);
// Check that BaseIndex and DerivedIndex fall within the 'gc parameters'
// section of the statepoint's argument
Assert(StatepointCS.arg_size() > 0,
"gc.statepoint: insufficient arguments");
Assert(isa<ConstantInt>(StatepointCS.getArgument(3)),
"gc.statement: number of call arguments must be constant integer");
const unsigned NumCallArgs =
cast<ConstantInt>(StatepointCS.getArgument(3))->getZExtValue();
Assert(StatepointCS.arg_size() > NumCallArgs + 5,
"gc.statepoint: mismatch in number of call arguments");
Assert(isa<ConstantInt>(StatepointCS.getArgument(NumCallArgs + 5)),
"gc.statepoint: number of transition arguments must be "
"a constant integer");
const int NumTransitionArgs =
cast<ConstantInt>(StatepointCS.getArgument(NumCallArgs + 5))
->getZExtValue();
const int DeoptArgsStart = 4 + NumCallArgs + 1 + NumTransitionArgs + 1;
Assert(isa<ConstantInt>(StatepointCS.getArgument(DeoptArgsStart)),
"gc.statepoint: number of deoptimization arguments must be "
"a constant integer");
const int NumDeoptArgs =
cast<ConstantInt>(StatepointCS.getArgument(DeoptArgsStart))->getZExtValue();
const int GCParamArgsStart = DeoptArgsStart + 1 + NumDeoptArgs;
const int GCParamArgsEnd = StatepointCS.arg_size();
Assert(GCParamArgsStart <= BaseIndex && BaseIndex < GCParamArgsEnd,
"gc.relocate: statepoint base index doesn't fall within the "
"'gc parameters' section of the statepoint call",
CS);
Assert(GCParamArgsStart <= DerivedIndex && DerivedIndex < GCParamArgsEnd,
"gc.relocate: statepoint derived index doesn't fall within the "
"'gc parameters' section of the statepoint call",
CS);
// Relocated value must be a pointer type, but gc_relocate does not need to return the
// same pointer type as the relocated pointer. It can be casted to the correct type later
// if it's desired. However, they must have the same address space.
GCRelocateOperands Operands(CS);
Assert(Operands.getDerivedPtr()->getType()->isPointerTy(),
"gc.relocate: relocated value must be a gc pointer", CS);
// gc_relocate return type must be a pointer type, and is verified earlier in
// VerifyIntrinsicType().
Assert(cast<PointerType>(CS.getType())->getAddressSpace() ==
cast<PointerType>(Operands.getDerivedPtr()->getType())->getAddressSpace(),
"gc.relocate: relocating a pointer shouldn't change its address space", CS);
break;
}
};
}
/// \brief Carefully grab the subprogram from a local scope.
///
/// This carefully grabs the subprogram from a local scope, avoiding the
/// built-in assertions that would typically fire.
static DISubprogram *getSubprogram(Metadata *LocalScope) {
if (!LocalScope)
return nullptr;
if (auto *SP = dyn_cast<DISubprogram>(LocalScope))
return SP;
if (auto *LB = dyn_cast<DILexicalBlockBase>(LocalScope))
return getSubprogram(LB->getRawScope());
// Just return null; broken scope chains are checked elsewhere.
assert(!isa<DILocalScope>(LocalScope) && "Unknown type of local scope");
return nullptr;
}
template <class DbgIntrinsicTy>
void Verifier::visitDbgIntrinsic(StringRef Kind, DbgIntrinsicTy &DII) {
auto *MD = cast<MetadataAsValue>(DII.getArgOperand(0))->getMetadata();
Assert(isa<ValueAsMetadata>(MD) ||
(isa<MDNode>(MD) && !cast<MDNode>(MD)->getNumOperands()),
"invalid llvm.dbg." + Kind + " intrinsic address/value", &DII, MD);
Assert(isa<DILocalVariable>(DII.getRawVariable()),
"invalid llvm.dbg." + Kind + " intrinsic variable", &DII,
DII.getRawVariable());
Assert(isa<DIExpression>(DII.getRawExpression()),
"invalid llvm.dbg." + Kind + " intrinsic expression", &DII,
DII.getRawExpression());
// Ignore broken !dbg attachments; they're checked elsewhere.
if (MDNode *N = DII.getDebugLoc().getAsMDNode())
if (!isa<DILocation>(N))
return;
BasicBlock *BB = DII.getParent();
Function *F = BB ? BB->getParent() : nullptr;
// The scopes for variables and !dbg attachments must agree.
DILocalVariable *Var = DII.getVariable();
DILocation *Loc = DII.getDebugLoc();
Assert(Loc, "llvm.dbg." + Kind + " intrinsic requires a !dbg attachment",
&DII, BB, F);
DISubprogram *VarSP = getSubprogram(Var->getRawScope());
DISubprogram *LocSP = getSubprogram(Loc->getRawScope());
if (!VarSP || !LocSP)
return; // Broken scope chains are checked elsewhere.
Assert(VarSP == LocSP, "mismatched subprogram between llvm.dbg." + Kind +
" variable and !dbg attachment",
&DII, BB, F, Var, Var->getScope()->getSubprogram(), Loc,
Loc->getScope()->getSubprogram());
}
template <class MapTy>
static uint64_t getVariableSize(const DILocalVariable &V, const MapTy &Map) {
// Be careful of broken types (checked elsewhere).
const Metadata *RawType = V.getRawType();
while (RawType) {
// Try to get the size directly.
if (auto *T = dyn_cast<DIType>(RawType))
if (uint64_t Size = T->getSizeInBits())
return Size;
if (auto *DT = dyn_cast<DIDerivedType>(RawType)) {
// Look at the base type.
RawType = DT->getRawBaseType();
continue;
}
if (auto *S = dyn_cast<MDString>(RawType)) {
// Don't error on missing types (checked elsewhere).
RawType = Map.lookup(S);
continue;
}
// Missing type or size.
break;
}
// Fail gracefully.
return 0;
}
template <class MapTy>
void Verifier::verifyBitPieceExpression(const DbgInfoIntrinsic &I,
const MapTy &TypeRefs) {
DILocalVariable *V;
DIExpression *E;
if (auto *DVI = dyn_cast<DbgValueInst>(&I)) {
V = dyn_cast_or_null<DILocalVariable>(DVI->getRawVariable());
E = dyn_cast_or_null<DIExpression>(DVI->getRawExpression());
} else {
auto *DDI = cast<DbgDeclareInst>(&I);
V = dyn_cast_or_null<DILocalVariable>(DDI->getRawVariable());
E = dyn_cast_or_null<DIExpression>(DDI->getRawExpression());
}
// We don't know whether this intrinsic verified correctly.
if (!V || !E || !E->isValid())
return;
// Nothing to do if this isn't a bit piece expression.
if (!E->isBitPiece())
return;
// The frontend helps out GDB by emitting the members of local anonymous
// unions as artificial local variables with shared storage. When SROA splits
// the storage for artificial local variables that are smaller than the entire
// union, the overhang piece will be outside of the allotted space for the
// variable and this check fails.
// FIXME: Remove this check as soon as clang stops doing this; it hides bugs.
if (V->isArtificial())
return;
// If there's no size, the type is broken, but that should be checked
// elsewhere.
uint64_t VarSize = getVariableSize(*V, TypeRefs);
if (!VarSize)
return;
unsigned PieceSize = E->getBitPieceSize();
unsigned PieceOffset = E->getBitPieceOffset();
Assert(PieceSize + PieceOffset <= VarSize,
"piece is larger than or outside of variable", &I, V, E);
Assert(PieceSize != VarSize, "piece covers entire variable", &I, V, E);
}
void Verifier::visitUnresolvedTypeRef(const MDString *S, const MDNode *N) {
// This is in its own function so we get an error for each bad type ref (not
// just the first).
Assert(false, "unresolved type ref", S, N);
}
void Verifier::verifyTypeRefs() {
auto *CUs = M->getNamedMetadata("llvm.dbg.cu");
if (!CUs)
return;
// Visit all the compile units again to map the type references.
SmallDenseMap<const MDString *, const DIType *, 32> TypeRefs;
for (auto *CU : CUs->operands())
if (auto Ts = cast<DICompileUnit>(CU)->getRetainedTypes())
for (DIType *Op : Ts)
if (auto *T = dyn_cast<DICompositeType>(Op))
if (auto *S = T->getRawIdentifier()) {
UnresolvedTypeRefs.erase(S);
TypeRefs.insert(std::make_pair(S, T));
}
// Verify debug info intrinsic bit piece expressions. This needs a second
// pass through the intructions, since we haven't built TypeRefs yet when
// verifying functions, and simply queuing the DbgInfoIntrinsics to evaluate
// later/now would queue up some that could be later deleted.
for (const Function &F : *M)
for (const BasicBlock &BB : F)
for (const Instruction &I : BB)
if (auto *DII = dyn_cast<DbgInfoIntrinsic>(&I))
verifyBitPieceExpression(*DII, TypeRefs);
// Return early if all typerefs were resolved.
if (UnresolvedTypeRefs.empty())
return;
// Sort the unresolved references by name so the output is deterministic.
typedef std::pair<const MDString *, const MDNode *> TypeRef;
SmallVector<TypeRef, 32> Unresolved(UnresolvedTypeRefs.begin(),
UnresolvedTypeRefs.end());
std::sort(Unresolved.begin(), Unresolved.end(),
[](const TypeRef &LHS, const TypeRef &RHS) {
return LHS.first->getString() < RHS.first->getString();
});
// Visit the unresolved refs (printing out the errors).
for (const TypeRef &TR : Unresolved)
visitUnresolvedTypeRef(TR.first, TR.second);
}
//===----------------------------------------------------------------------===//
// Implement the public interfaces to this file...
//===----------------------------------------------------------------------===//
bool llvm::verifyFunction(const Function &f, raw_ostream *OS) {
Function &F = const_cast<Function &>(f);
assert(!F.isDeclaration() && "Cannot verify external functions");
raw_null_ostream NullStr;
Verifier V(OS ? *OS : NullStr);
// Note that this function's return value is inverted from what you would
// expect of a function called "verify".
return !V.verify(F);
}
bool llvm::verifyModule(const Module &M, raw_ostream *OS) {
raw_null_ostream NullStr;
Verifier V(OS ? *OS : NullStr);
bool Broken = false;
for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I)
if (!I->isDeclaration() && !I->isMaterializable())
Broken |= !V.verify(*I);
// Note that this function's return value is inverted from what you would
// expect of a function called "verify".
return !V.verify(M) || Broken;
}
namespace {
struct VerifierLegacyPass : public FunctionPass {
static char ID;
Verifier V;
bool FatalErrors;
VerifierLegacyPass() : FunctionPass(ID), V(dbgs()), FatalErrors(true) {
initializeVerifierLegacyPassPass(*PassRegistry::getPassRegistry());
}
explicit VerifierLegacyPass(bool FatalErrors)
: FunctionPass(ID), V(dbgs()), FatalErrors(FatalErrors) {
initializeVerifierLegacyPassPass(*PassRegistry::getPassRegistry());
}
bool runOnFunction(Function &F) override {
return false;
if (!V.verify(F) && FatalErrors)
report_fatal_error("Broken function found, compilation aborted!");
return false;
}
bool doFinalization(Module &M) override {
if (!V.verify(M) && FatalErrors)
report_fatal_error("Broken module found, compilation aborted!");
return false;
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.setPreservesAll();
}
};
}
char VerifierLegacyPass::ID = 0;
INITIALIZE_PASS(VerifierLegacyPass, "verify", "Module Verifier", false, false)
FunctionPass *llvm::createVerifierPass(bool FatalErrors) {
return new VerifierLegacyPass(FatalErrors);
}
PreservedAnalyses VerifierPass::run(Module &M) {
if (verifyModule(M, &dbgs()) && FatalErrors)
report_fatal_error("Broken module found, compilation aborted!");
return PreservedAnalyses::all();
}
PreservedAnalyses VerifierPass::run(Function &F) {
if (verifyFunction(F, &dbgs()) && FatalErrors)
report_fatal_error("Broken function found, compilation aborted!");
return PreservedAnalyses::all();
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/Metadata.cpp | //===- Metadata.cpp - Implement Metadata classes --------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the Metadata classes.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/Metadata.h"
#include "LLVMContextImpl.h"
#include "MetadataImpl.h"
#include "SymbolTableListTraitsImpl.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/IR/ConstantRange.h"
#include "llvm/IR/DebugInfoMetadata.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/ValueHandle.h"
using namespace llvm;
MetadataAsValue::MetadataAsValue(Type *Ty, Metadata *MD)
: Value(Ty, MetadataAsValueVal), MD(MD) {
track();
}
MetadataAsValue::~MetadataAsValue() {
getType()->getContext().pImpl->MetadataAsValues.erase(MD);
untrack();
}
/// \brief Canonicalize metadata arguments to intrinsics.
///
/// To support bitcode upgrades (and assembly semantic sugar) for \a
/// MetadataAsValue, we need to canonicalize certain metadata.
///
/// - nullptr is replaced by an empty MDNode.
/// - An MDNode with a single null operand is replaced by an empty MDNode.
/// - An MDNode whose only operand is a \a ConstantAsMetadata gets skipped.
///
/// This maintains readability of bitcode from when metadata was a type of
/// value, and these bridges were unnecessary.
static Metadata *canonicalizeMetadataForValue(LLVMContext &Context,
Metadata *MD) {
if (!MD)
// !{}
return MDNode::get(Context, None);
// Return early if this isn't a single-operand MDNode.
auto *N = dyn_cast<MDNode>(MD);
if (!N || N->getNumOperands() != 1)
return MD;
if (!N->getOperand(0))
// !{}
return MDNode::get(Context, None);
if (auto *C = dyn_cast<ConstantAsMetadata>(N->getOperand(0)))
// Look through the MDNode.
return C;
return MD;
}
MetadataAsValue *MetadataAsValue::get(LLVMContext &Context, Metadata *MD) {
MD = canonicalizeMetadataForValue(Context, MD);
auto *&Entry = Context.pImpl->MetadataAsValues[MD];
if (!Entry)
Entry = new MetadataAsValue(Type::getMetadataTy(Context), MD);
return Entry;
}
MetadataAsValue *MetadataAsValue::getIfExists(LLVMContext &Context,
Metadata *MD) {
MD = canonicalizeMetadataForValue(Context, MD);
auto &Store = Context.pImpl->MetadataAsValues;
return Store.lookup(MD);
}
void MetadataAsValue::handleChangedMetadata(Metadata *MD) {
LLVMContext &Context = getContext();
MD = canonicalizeMetadataForValue(Context, MD);
auto &Store = Context.pImpl->MetadataAsValues;
// Stop tracking the old metadata.
Store.erase(this->MD);
untrack();
this->MD = nullptr;
// Start tracking MD, or RAUW if necessary.
auto *&Entry = Store[MD];
if (Entry) {
replaceAllUsesWith(Entry);
delete this;
return;
}
this->MD = MD;
track();
Entry = this;
}
void MetadataAsValue::track() {
if (MD)
MetadataTracking::track(&MD, *MD, *this);
}
void MetadataAsValue::untrack() {
if (MD)
MetadataTracking::untrack(MD);
}
void ReplaceableMetadataImpl::addRef(void *Ref, OwnerTy Owner) {
bool WasInserted =
UseMap.insert(std::make_pair(Ref, std::make_pair(Owner, NextIndex)))
.second;
(void)WasInserted;
assert(WasInserted && "Expected to add a reference");
++NextIndex;
assert(NextIndex != 0 && "Unexpected overflow");
}
void ReplaceableMetadataImpl::dropRef(void *Ref) {
bool WasErased = UseMap.erase(Ref);
(void)WasErased;
// assert(WasErased && "Expected to drop a reference"); // HLSL Change - not while cleaning up OOM
}
void ReplaceableMetadataImpl::moveRef(void *Ref, void *New,
const Metadata &MD) {
auto I = UseMap.find(Ref);
assert(I != UseMap.end() && "Expected to move a reference");
auto OwnerAndIndex = I->second;
UseMap.erase(I);
bool WasInserted = UseMap.insert(std::make_pair(New, OwnerAndIndex)).second;
(void)WasInserted;
assert(WasInserted && "Expected to add a reference");
// Check that the references are direct if there's no owner.
(void)MD;
assert((OwnerAndIndex.first || *static_cast<Metadata **>(Ref) == &MD) &&
"Reference without owner must be direct");
assert((OwnerAndIndex.first || *static_cast<Metadata **>(New) == &MD) &&
"Reference without owner must be direct");
}
void ReplaceableMetadataImpl::replaceAllUsesWith(Metadata *MD) {
assert(!(MD && isa<MDNode>(MD) && cast<MDNode>(MD)->isTemporary()) &&
"Expected non-temp node");
if (UseMap.empty())
return;
// Copy out uses since UseMap will get touched below.
typedef std::pair<void *, std::pair<OwnerTy, uint64_t>> UseTy;
SmallVector<UseTy, 8> Uses(UseMap.begin(), UseMap.end());
std::sort(Uses.begin(), Uses.end(), [](const UseTy &L, const UseTy &R) {
return L.second.second < R.second.second;
});
for (const auto &Pair : Uses) {
// Check that this Ref hasn't disappeared after RAUW (when updating a
// previous Ref).
if (!UseMap.count(Pair.first))
continue;
OwnerTy Owner = Pair.second.first;
if (!Owner) {
// Update unowned tracking references directly.
Metadata *&Ref = *static_cast<Metadata **>(Pair.first);
Ref = MD;
if (MD)
MetadataTracking::track(Ref);
UseMap.erase(Pair.first);
continue;
}
// Check for MetadataAsValue.
if (Owner.is<MetadataAsValue *>()) {
Owner.get<MetadataAsValue *>()->handleChangedMetadata(MD);
continue;
}
// There's a Metadata owner -- dispatch.
Metadata *OwnerMD = Owner.get<Metadata *>();
switch (OwnerMD->getMetadataID()) {
#define HANDLE_METADATA_LEAF(CLASS) \
case Metadata::CLASS##Kind: \
cast<CLASS>(OwnerMD)->handleChangedOperand(Pair.first, MD); \
continue;
#include "llvm/IR/Metadata.def"
default:
llvm_unreachable("Invalid metadata subclass");
}
}
assert(UseMap.empty() && "Expected all uses to be replaced");
}
void ReplaceableMetadataImpl::resolveAllUses(bool ResolveUsers) {
if (UseMap.empty())
return;
if (!ResolveUsers) {
UseMap.clear();
return;
}
// Copy out uses since UseMap could get touched below.
typedef std::pair<void *, std::pair<OwnerTy, uint64_t>> UseTy;
SmallVector<UseTy, 8> Uses(UseMap.begin(), UseMap.end());
std::sort(Uses.begin(), Uses.end(), [](const UseTy &L, const UseTy &R) {
return L.second.second < R.second.second;
});
UseMap.clear();
for (const auto &Pair : Uses) {
auto Owner = Pair.second.first;
if (!Owner)
continue;
if (Owner.is<MetadataAsValue *>())
continue;
// Resolve MDNodes that point at this.
auto *OwnerMD = dyn_cast<MDNode>(Owner.get<Metadata *>());
if (!OwnerMD)
continue;
if (OwnerMD->isResolved())
continue;
OwnerMD->decrementUnresolvedOperandCount();
}
}
static Function *getLocalFunction(Value *V) {
assert(V && "Expected value");
if (auto *A = dyn_cast<Argument>(V))
return A->getParent();
if (BasicBlock *BB = cast<Instruction>(V)->getParent())
return BB->getParent();
return nullptr;
}
ValueAsMetadata *ValueAsMetadata::get(Value *V) {
assert(V && "Unexpected null Value");
auto &Context = V->getContext();
auto *&Entry = Context.pImpl->ValuesAsMetadata[V];
if (!Entry) {
assert((isa<Constant>(V) || isa<Argument>(V) || isa<Instruction>(V)) &&
"Expected constant or function-local value");
assert(!V->IsUsedByMD &&
"Expected this to be the only metadata use");
V->IsUsedByMD = true;
if (auto *C = dyn_cast<Constant>(V))
Entry = new ConstantAsMetadata(C);
else
Entry = new LocalAsMetadata(V);
}
return Entry;
}
ValueAsMetadata *ValueAsMetadata::getIfExists(Value *V) {
assert(V && "Unexpected null Value");
return V->getContext().pImpl->ValuesAsMetadata.lookup(V);
}
void ValueAsMetadata::handleDeletion(Value *V) {
assert(V && "Expected valid value");
auto &Store = V->getType()->getContext().pImpl->ValuesAsMetadata;
auto I = Store.find(V);
if (I == Store.end())
return;
// Remove old entry from the map.
ValueAsMetadata *MD = I->second;
// assert(MD && "Expected valid metadata"); // HLSL Change - MD might be nullptr under OOM
// assert(MD->getValue() == V && "Expected valid mapping"); // HLSL Change - MD might be nullptr under OOM
Store.erase(I);
// Delete the metadata.
if (MD) MD->replaceAllUsesWith(nullptr); // HLSL Change - MD might be nullptr under OOM
delete MD;
}
void ValueAsMetadata::handleRAUW(Value *From, Value *To) {
assert(From && "Expected valid value");
assert(To && "Expected valid value");
assert(From != To && "Expected changed value");
assert(From->getType() == To->getType() && "Unexpected type change");
LLVMContext &Context = From->getType()->getContext();
auto &Store = Context.pImpl->ValuesAsMetadata;
auto I = Store.find(From);
if (I == Store.end()) {
assert(!From->IsUsedByMD &&
"Expected From not to be used by metadata");
return;
}
// Remove old entry from the map.
assert(From->IsUsedByMD &&
"Expected From to be used by metadata");
From->IsUsedByMD = false;
ValueAsMetadata *MD = I->second;
assert(MD && "Expected valid metadata");
assert(MD->getValue() == From && "Expected valid mapping");
Store.erase(I);
if (isa<LocalAsMetadata>(MD)) {
if (auto *C = dyn_cast<Constant>(To)) {
// Local became a constant.
MD->replaceAllUsesWith(ConstantAsMetadata::get(C));
delete MD;
return;
}
if (getLocalFunction(From) && getLocalFunction(To) &&
getLocalFunction(From) != getLocalFunction(To)) {
// Function changed.
MD->replaceAllUsesWith(nullptr);
delete MD;
return;
}
} else if (!isa<Constant>(To)) {
// Changed to function-local value.
MD->replaceAllUsesWith(nullptr);
delete MD;
return;
}
auto *&Entry = Store[To];
if (Entry) {
// The target already exists.
MD->replaceAllUsesWith(Entry);
delete MD;
return;
}
// Update MD in place (and update the map entry).
assert(!To->IsUsedByMD &&
"Expected this to be the only metadata use");
To->IsUsedByMD = true;
MD->V = To;
Entry = MD;
}
//===----------------------------------------------------------------------===//
// MDString implementation.
//
MDString *MDString::get(LLVMContext &Context, StringRef Str) {
auto &Store = Context.pImpl->MDStringCache;
auto I = Store.find(Str);
if (I != Store.end())
return &I->second;
auto *Entry =
StringMapEntry<MDString>::Create(Str, Store.getAllocator(), MDString());
// HLSL Change Begin: Don't leak on insertion failure
try {
bool WasInserted = Store.insert(Entry);
(void)WasInserted;
assert(WasInserted && "Expected entry to be inserted");
}
catch (...) {
Entry->Destroy();
throw;
}
// HLSL Change End
Entry->second.Entry = Entry;
return &Entry->second;
}
StringRef MDString::getString() const {
assert(Entry && "Expected to find string map entry");
return Entry->first();
}
//===----------------------------------------------------------------------===//
// MDNode implementation.
//
// Assert that the MDNode types will not be unaligned by the objects
// prepended to them.
#define HANDLE_MDNODE_LEAF(CLASS) \
static_assert( \
llvm::AlignOf<uint64_t>::Alignment >= llvm::AlignOf<CLASS>::Alignment, \
"Alignment is insufficient after objects prepended to " #CLASS);
#include "llvm/IR/Metadata.def"
void *MDNode::operator new(size_t Size, unsigned NumOps) {
size_t OpSize = NumOps * sizeof(MDOperand);
// uint64_t is the most aligned type we need support (ensured by static_assert
// above)
OpSize = RoundUpToAlignment(OpSize, llvm::alignOf<uint64_t>());
void *Ptr = reinterpret_cast<char *>(::operator new(OpSize + Size)) + OpSize;
MDOperand *O = static_cast<MDOperand *>(Ptr);
for (MDOperand *E = O - NumOps; O != E; --O)
(void)new (O - 1) MDOperand;
return Ptr;
}
void MDNode::operator delete(void *Mem) {
MDNode *N = static_cast<MDNode *>(Mem);
size_t OpSize = N->NumOperands * sizeof(MDOperand);
OpSize = RoundUpToAlignment(OpSize, llvm::alignOf<uint64_t>());
MDOperand *O = static_cast<MDOperand *>(Mem);
for (MDOperand *E = O - N->NumOperands; O != E; --O)
(O - 1)->~MDOperand();
::operator delete(reinterpret_cast<char *>(Mem) - OpSize);
}
MDNode::MDNode(LLVMContext &Context, unsigned ID, StorageType Storage,
ArrayRef<Metadata *> Ops1, ArrayRef<Metadata *> Ops2)
: Metadata(ID, Storage), NumOperands(Ops1.size() + Ops2.size()),
NumUnresolved(0), Context(Context) {
unsigned Op = 0;
for (Metadata *MD : Ops1)
setOperand(Op++, MD);
for (Metadata *MD : Ops2)
setOperand(Op++, MD);
if (isDistinct())
return;
if (isUniqued())
// Check whether any operands are unresolved, requiring re-uniquing. If
// not, don't support RAUW.
if (!countUnresolvedOperands())
return;
this->Context.makeReplaceable(make_unique<ReplaceableMetadataImpl>(Context));
}
TempMDNode MDNode::clone() const {
switch (getMetadataID()) {
default:
llvm_unreachable("Invalid MDNode subclass");
#define HANDLE_MDNODE_LEAF(CLASS) \
case CLASS##Kind: \
return cast<CLASS>(this)->cloneImpl();
#include "llvm/IR/Metadata.def"
}
}
static bool isOperandUnresolved(Metadata *Op) {
if (auto *N = dyn_cast_or_null<MDNode>(Op))
return !N->isResolved();
return false;
}
unsigned MDNode::countUnresolvedOperands() {
assert(NumUnresolved == 0 && "Expected unresolved ops to be uncounted");
NumUnresolved = std::count_if(op_begin(), op_end(), isOperandUnresolved);
return NumUnresolved;
}
void MDNode::makeUniqued() {
assert(isTemporary() && "Expected this to be temporary");
assert(!isResolved() && "Expected this to be unresolved");
// Enable uniquing callbacks.
for (auto &Op : mutable_operands())
Op.reset(Op.get(), this);
// Make this 'uniqued'.
Storage = Uniqued;
if (!countUnresolvedOperands())
resolve();
assert(isUniqued() && "Expected this to be uniqued");
}
void MDNode::makeDistinct() {
assert(isTemporary() && "Expected this to be temporary");
assert(!isResolved() && "Expected this to be unresolved");
// Pretend to be uniqued, resolve the node, and then store in distinct table.
Storage = Uniqued;
resolve();
storeDistinctInContext();
assert(isDistinct() && "Expected this to be distinct");
assert(isResolved() && "Expected this to be resolved");
}
void MDNode::resolve() {
assert(isUniqued() && "Expected this to be uniqued");
assert(!isResolved() && "Expected this to be unresolved");
// Move the map, so that this immediately looks resolved.
auto Uses = Context.takeReplaceableUses();
NumUnresolved = 0;
assert(isResolved() && "Expected this to be resolved");
// Drop RAUW support.
Uses->resolveAllUses();
}
void MDNode::resolveAfterOperandChange(Metadata *Old, Metadata *New) {
assert(NumUnresolved != 0 && "Expected unresolved operands");
// Check if an operand was resolved.
if (!isOperandUnresolved(Old)) {
if (isOperandUnresolved(New))
// An operand was un-resolved!
++NumUnresolved;
} else if (!isOperandUnresolved(New))
decrementUnresolvedOperandCount();
}
void MDNode::decrementUnresolvedOperandCount() {
if (!--NumUnresolved)
// Last unresolved operand has just been resolved.
resolve();
}
void MDNode::resolveCycles() {
if (isResolved())
return;
// Resolve this node immediately.
resolve();
// Resolve all operands.
for (const auto &Op : operands()) {
auto *N = dyn_cast_or_null<MDNode>(Op);
if (!N)
continue;
assert(!N->isTemporary() &&
"Expected all forward declarations to be resolved");
if (!N->isResolved())
N->resolveCycles();
}
}
static bool hasSelfReference(MDNode *N) {
for (Metadata *MD : N->operands())
if (MD == N)
return true;
return false;
}
MDNode *MDNode::replaceWithPermanentImpl() {
if (hasSelfReference(this))
return replaceWithDistinctImpl();
return replaceWithUniquedImpl();
}
MDNode *MDNode::replaceWithUniquedImpl() {
// Try to uniquify in place.
MDNode *UniquedNode = uniquify();
if (UniquedNode == this) {
makeUniqued();
return this;
}
// Collision, so RAUW instead.
replaceAllUsesWith(UniquedNode);
deleteAsSubclass();
return UniquedNode;
}
MDNode *MDNode::replaceWithDistinctImpl() {
makeDistinct();
return this;
}
void MDTuple::recalculateHash() {
setHash(MDTupleInfo::KeyTy::calculateHash(this));
}
void MDNode::dropAllReferences() {
for (unsigned I = 0, E = NumOperands; I != E; ++I)
setOperand(I, nullptr);
if (!isResolved()) {
Context.getReplaceableUses()->resolveAllUses(/* ResolveUsers */ false);
(void)Context.takeReplaceableUses();
}
}
void MDNode::handleChangedOperand(void *Ref, Metadata *New) {
unsigned Op = static_cast<MDOperand *>(Ref) - op_begin();
assert(Op < getNumOperands() && "Expected valid operand");
if (!isUniqued()) {
// This node is not uniqued. Just set the operand and be done with it.
setOperand(Op, New);
return;
}
// This node is uniqued.
eraseFromStore();
Metadata *Old = getOperand(Op);
setOperand(Op, New);
// Drop uniquing for self-reference cycles.
if (New == this) {
if (!isResolved())
resolve();
storeDistinctInContext();
return;
}
// Re-unique the node.
auto *Uniqued = uniquify();
if (Uniqued == this) {
if (!isResolved())
resolveAfterOperandChange(Old, New);
return;
}
// Collision.
if (!isResolved()) {
// Still unresolved, so RAUW.
//
// First, clear out all operands to prevent any recursion (similar to
// dropAllReferences(), but we still need the use-list).
for (unsigned O = 0, E = getNumOperands(); O != E; ++O)
setOperand(O, nullptr);
Context.getReplaceableUses()->replaceAllUsesWith(Uniqued);
deleteAsSubclass();
return;
}
// Store in non-uniqued form if RAUW isn't possible.
storeDistinctInContext();
}
void MDNode::deleteAsSubclass() {
switch (getMetadataID()) {
default:
llvm_unreachable("Invalid subclass of MDNode");
#define HANDLE_MDNODE_LEAF(CLASS) \
case CLASS##Kind: \
delete cast<CLASS>(this); \
break;
#include "llvm/IR/Metadata.def"
}
}
template <class T, class InfoT>
static T *uniquifyImpl(T *N, DenseSet<T *, InfoT> &Store) {
if (T *U = getUniqued(Store, N))
return U;
Store.insert(N);
return N;
}
template <class NodeTy> struct MDNode::HasCachedHash {
typedef char Yes[1];
typedef char No[2];
template <class U, U Val> struct SFINAE {};
template <class U>
static Yes &check(SFINAE<void (U::*)(unsigned), &U::setHash> *);
template <class U> static No &check(...);
static const bool value = sizeof(check<NodeTy>(nullptr)) == sizeof(Yes);
};
MDNode *MDNode::uniquify() {
assert(!hasSelfReference(this) && "Cannot uniquify a self-referencing node");
// Try to insert into uniquing store.
switch (getMetadataID()) {
default:
llvm_unreachable("Invalid subclass of MDNode");
#define HANDLE_MDNODE_LEAF(CLASS) \
case CLASS##Kind: { \
CLASS *SubclassThis = cast<CLASS>(this); \
std::integral_constant<bool, HasCachedHash<CLASS>::value> \
ShouldRecalculateHash; \
dispatchRecalculateHash(SubclassThis, ShouldRecalculateHash); \
return uniquifyImpl(SubclassThis, getContext().pImpl->CLASS##s); \
}
#include "llvm/IR/Metadata.def"
}
}
void MDNode::eraseFromStore() {
switch (getMetadataID()) {
default:
llvm_unreachable("Invalid subclass of MDNode");
#define HANDLE_MDNODE_LEAF(CLASS) \
case CLASS##Kind: \
getContext().pImpl->CLASS##s.erase(cast<CLASS>(this)); \
break;
#include "llvm/IR/Metadata.def"
}
}
MDTuple *MDTuple::getImpl(LLVMContext &Context, ArrayRef<Metadata *> MDs,
StorageType Storage, bool ShouldCreate) {
unsigned Hash = 0;
if (Storage == Uniqued) {
MDTupleInfo::KeyTy Key(MDs);
if (auto *N = getUniqued(Context.pImpl->MDTuples, Key))
return N;
if (!ShouldCreate)
return nullptr;
Hash = Key.getHash();
} else {
assert(ShouldCreate && "Expected non-uniqued nodes to always be created");
}
// HLSL Change - guard with try/catch
MDTuple *MDTuplePtr(new (MDs.size()) MDTuple(Context, Storage, Hash, MDs));
MDTuple *Result;
try {
Result = storeImpl(MDTuplePtr, Storage, Context.pImpl->MDTuples);
} catch (...) {
MDTuplePtr->deleteAsSubclass();
throw;
}
return Result;
}
void MDNode::deleteTemporary(MDNode *N) {
assert(N->isTemporary() && "Expected temporary node");
N->replaceAllUsesWith(nullptr);
N->deleteAsSubclass();
}
void MDNode::storeDistinctInContext() {
assert(isResolved() && "Expected resolved nodes");
Storage = Distinct;
// Reset the hash.
switch (getMetadataID()) {
default:
llvm_unreachable("Invalid subclass of MDNode");
#define HANDLE_MDNODE_LEAF(CLASS) \
case CLASS##Kind: { \
std::integral_constant<bool, HasCachedHash<CLASS>::value> ShouldResetHash; \
dispatchResetHash(cast<CLASS>(this), ShouldResetHash); \
break; \
}
#include "llvm/IR/Metadata.def"
}
getContext().pImpl->DistinctMDNodes.insert(this);
}
void MDNode::replaceOperandWith(unsigned I, Metadata *New) {
if (getOperand(I) == New)
return;
if (!isUniqued()) {
setOperand(I, New);
return;
}
handleChangedOperand(mutable_begin() + I, New);
}
void MDNode::setOperand(unsigned I, Metadata *New) {
assert(I < NumOperands);
mutable_begin()[I].reset(New, isUniqued() ? this : nullptr);
}
/// \brief Get a node, or a self-reference that looks like it.
///
/// Special handling for finding self-references, for use by \a
/// MDNode::concatenate() and \a MDNode::intersect() to maintain behaviour from
/// when self-referencing nodes were still uniqued. If the first operand has
/// the same operands as \c Ops, return the first operand instead.
static MDNode *getOrSelfReference(LLVMContext &Context,
ArrayRef<Metadata *> Ops) {
if (!Ops.empty())
if (MDNode *N = dyn_cast_or_null<MDNode>(Ops[0]))
if (N->getNumOperands() == Ops.size() && N == N->getOperand(0)) {
for (unsigned I = 1, E = Ops.size(); I != E; ++I)
if (Ops[I] != N->getOperand(I))
return MDNode::get(Context, Ops);
return N;
}
return MDNode::get(Context, Ops);
}
MDNode *MDNode::concatenate(MDNode *A, MDNode *B) {
if (!A)
return B;
if (!B)
return A;
SmallVector<Metadata *, 4> MDs;
MDs.reserve(A->getNumOperands() + B->getNumOperands());
MDs.append(A->op_begin(), A->op_end());
MDs.append(B->op_begin(), B->op_end());
// FIXME: This preserves long-standing behaviour, but is it really the right
// behaviour? Or was that an unintended side-effect of node uniquing?
return getOrSelfReference(A->getContext(), MDs);
}
MDNode *MDNode::intersect(MDNode *A, MDNode *B) {
if (!A || !B)
return nullptr;
SmallVector<Metadata *, 4> MDs;
for (Metadata *MD : A->operands())
if (std::find(B->op_begin(), B->op_end(), MD) != B->op_end())
MDs.push_back(MD);
// FIXME: This preserves long-standing behaviour, but is it really the right
// behaviour? Or was that an unintended side-effect of node uniquing?
return getOrSelfReference(A->getContext(), MDs);
}
MDNode *MDNode::getMostGenericAliasScope(MDNode *A, MDNode *B) {
if (!A || !B)
return nullptr;
SmallVector<Metadata *, 4> MDs(B->op_begin(), B->op_end());
for (Metadata *MD : A->operands())
if (std::find(B->op_begin(), B->op_end(), MD) == B->op_end())
MDs.push_back(MD);
// FIXME: This preserves long-standing behaviour, but is it really the right
// behaviour? Or was that an unintended side-effect of node uniquing?
return getOrSelfReference(A->getContext(), MDs);
}
MDNode *MDNode::getMostGenericFPMath(MDNode *A, MDNode *B) {
if (!A || !B)
return nullptr;
APFloat AVal = mdconst::extract<ConstantFP>(A->getOperand(0))->getValueAPF();
APFloat BVal = mdconst::extract<ConstantFP>(B->getOperand(0))->getValueAPF();
if (AVal.compare(BVal) == APFloat::cmpLessThan)
return A;
return B;
}
static bool isContiguous(const ConstantRange &A, const ConstantRange &B) {
return A.getUpper() == B.getLower() || A.getLower() == B.getUpper();
}
static bool canBeMerged(const ConstantRange &A, const ConstantRange &B) {
return !A.intersectWith(B).isEmptySet() || isContiguous(A, B);
}
static bool tryMergeRange(SmallVectorImpl<ConstantInt *> &EndPoints,
ConstantInt *Low, ConstantInt *High) {
ConstantRange NewRange(Low->getValue(), High->getValue());
unsigned Size = EndPoints.size();
APInt LB = EndPoints[Size - 2]->getValue();
APInt LE = EndPoints[Size - 1]->getValue();
ConstantRange LastRange(LB, LE);
if (canBeMerged(NewRange, LastRange)) {
ConstantRange Union = LastRange.unionWith(NewRange);
Type *Ty = High->getType();
EndPoints[Size - 2] =
cast<ConstantInt>(ConstantInt::get(Ty, Union.getLower()));
EndPoints[Size - 1] =
cast<ConstantInt>(ConstantInt::get(Ty, Union.getUpper()));
return true;
}
return false;
}
static void addRange(SmallVectorImpl<ConstantInt *> &EndPoints,
ConstantInt *Low, ConstantInt *High) {
if (!EndPoints.empty())
if (tryMergeRange(EndPoints, Low, High))
return;
EndPoints.push_back(Low);
EndPoints.push_back(High);
}
MDNode *MDNode::getMostGenericRange(MDNode *A, MDNode *B) {
// Given two ranges, we want to compute the union of the ranges. This
// is slightly complitade by having to combine the intervals and merge
// the ones that overlap.
if (!A || !B)
return nullptr;
if (A == B)
return A;
// First, walk both lists in older of the lower boundary of each interval.
// At each step, try to merge the new interval to the last one we adedd.
SmallVector<ConstantInt *, 4> EndPoints;
int AI = 0;
int BI = 0;
int AN = A->getNumOperands() / 2;
int BN = B->getNumOperands() / 2;
while (AI < AN && BI < BN) {
ConstantInt *ALow = mdconst::extract<ConstantInt>(A->getOperand(2 * AI));
ConstantInt *BLow = mdconst::extract<ConstantInt>(B->getOperand(2 * BI));
if (ALow->getValue().slt(BLow->getValue())) {
addRange(EndPoints, ALow,
mdconst::extract<ConstantInt>(A->getOperand(2 * AI + 1)));
++AI;
} else {
addRange(EndPoints, BLow,
mdconst::extract<ConstantInt>(B->getOperand(2 * BI + 1)));
++BI;
}
}
while (AI < AN) {
addRange(EndPoints, mdconst::extract<ConstantInt>(A->getOperand(2 * AI)),
mdconst::extract<ConstantInt>(A->getOperand(2 * AI + 1)));
++AI;
}
while (BI < BN) {
addRange(EndPoints, mdconst::extract<ConstantInt>(B->getOperand(2 * BI)),
mdconst::extract<ConstantInt>(B->getOperand(2 * BI + 1)));
++BI;
}
// If we have more than 2 ranges (4 endpoints) we have to try to merge
// the last and first ones.
unsigned Size = EndPoints.size();
if (Size > 4) {
ConstantInt *FB = EndPoints[0];
ConstantInt *FE = EndPoints[1];
if (tryMergeRange(EndPoints, FB, FE)) {
for (unsigned i = 0; i < Size - 2; ++i) {
EndPoints[i] = EndPoints[i + 2];
}
EndPoints.resize(Size - 2);
}
}
// If in the end we have a single range, it is possible that it is now the
// full range. Just drop the metadata in that case.
if (EndPoints.size() == 2) {
ConstantRange Range(EndPoints[0]->getValue(), EndPoints[1]->getValue());
if (Range.isFullSet())
return nullptr;
}
SmallVector<Metadata *, 4> MDs;
MDs.reserve(EndPoints.size());
for (auto *I : EndPoints)
MDs.push_back(ConstantAsMetadata::get(I));
return MDNode::get(A->getContext(), MDs);
}
//===----------------------------------------------------------------------===//
// NamedMDNode implementation.
//
static SmallVector<TrackingMDRef, 4> &getNMDOps(void *Operands) {
return *(SmallVector<TrackingMDRef, 4> *)Operands;
}
NamedMDNode::NamedMDNode(const Twine &N)
: Name(N.str()), Parent(nullptr),
Operands(new SmallVector<TrackingMDRef, 4>()) {}
NamedMDNode::~NamedMDNode() {
dropAllReferences();
delete &getNMDOps(Operands);
}
unsigned NamedMDNode::getNumOperands() const {
return (unsigned)getNMDOps(Operands).size();
}
MDNode *NamedMDNode::getOperand(unsigned i) const {
assert(i < getNumOperands() && "Invalid Operand number!");
auto *N = getNMDOps(Operands)[i].get();
return cast_or_null<MDNode>(N);
}
void NamedMDNode::addOperand(MDNode *M) { getNMDOps(Operands).emplace_back(M); }
void NamedMDNode::setOperand(unsigned I, MDNode *New) {
assert(I < getNumOperands() && "Invalid operand number");
getNMDOps(Operands)[I].reset(New);
}
void NamedMDNode::eraseFromParent() {
getParent()->eraseNamedMetadata(this);
}
void NamedMDNode::dropAllReferences() {
getNMDOps(Operands).clear();
}
StringRef NamedMDNode::getName() const {
return StringRef(Name);
}
//===----------------------------------------------------------------------===//
// Instruction Metadata method implementations.
//
void MDAttachmentMap::set(unsigned ID, MDNode &MD) {
for (auto &I : Attachments)
if (I.first == ID) {
I.second.reset(&MD);
return;
}
Attachments.emplace_back(std::piecewise_construct, std::make_tuple(ID),
std::make_tuple(&MD));
}
void MDAttachmentMap::erase(unsigned ID) {
if (empty())
return;
// Common case is one/last value.
if (Attachments.back().first == ID) {
Attachments.pop_back();
return;
}
for (auto I = Attachments.begin(), E = std::prev(Attachments.end()); I != E;
++I)
if (I->first == ID) {
*I = std::move(Attachments.back());
Attachments.pop_back();
return;
}
}
MDNode *MDAttachmentMap::lookup(unsigned ID) const {
for (const auto &I : Attachments)
if (I.first == ID)
return I.second;
return nullptr;
}
void MDAttachmentMap::getAll(
SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
Result.append(Attachments.begin(), Attachments.end());
// Sort the resulting array so it is stable.
if (Result.size() > 1)
array_pod_sort(Result.begin(), Result.end());
}
void Instruction::setMetadata(StringRef Kind, MDNode *Node) {
if (!Node && !hasMetadata())
return;
setMetadata(getContext().getMDKindID(Kind), Node);
}
MDNode *Instruction::getMetadataImpl(StringRef Kind) const {
unsigned KindID = 0;
#if 0 // HLSL Change Starts
return getMetadataImpl(getContext().getMDKindID(Kind))
#else
// Calling special function to check for existence of string id,
// so it doesn't get instantiated in the context.
if (getContext().findMDKindID(Kind, &KindID))
return getMetadataImpl(KindID);
return nullptr;
#endif // HLSL Change Ends
}
void Instruction::dropUnknownMetadata(ArrayRef<unsigned> KnownIDs) {
SmallSet<unsigned, 5> KnownSet;
KnownSet.insert(KnownIDs.begin(), KnownIDs.end());
// Drop debug if needed
if (KnownSet.erase(LLVMContext::MD_dbg))
DbgLoc = DebugLoc();
if (!hasMetadataHashEntry())
return; // Nothing to remove!
auto &InstructionMetadata = getContext().pImpl->InstructionMetadata;
if (KnownSet.empty()) {
// Just drop our entry at the store.
InstructionMetadata.erase(this);
setHasMetadataHashEntry(false);
return;
}
auto &Info = InstructionMetadata[this];
Info.remove_if([&KnownSet](const std::pair<unsigned, TrackingMDNodeRef> &I) {
return !KnownSet.count(I.first);
});
if (Info.empty()) {
// Drop our entry at the store.
InstructionMetadata.erase(this);
setHasMetadataHashEntry(false);
}
}
/// setMetadata - Set the metadata of of the specified kind to the specified
/// node. This updates/replaces metadata if already present, or removes it if
/// Node is null.
void Instruction::setMetadata(unsigned KindID, MDNode *Node) {
if (!Node && !hasMetadata())
return;
// Handle 'dbg' as a special case since it is not stored in the hash table.
if (KindID == LLVMContext::MD_dbg) {
DbgLoc = DebugLoc(Node);
return;
}
// Handle the case when we're adding/updating metadata on an instruction.
if (Node) {
auto &Info = getContext().pImpl->InstructionMetadata[this];
assert(!Info.empty() == hasMetadataHashEntry() &&
"HasMetadata bit is wonked");
if (Info.empty())
setHasMetadataHashEntry(true);
Info.set(KindID, *Node);
return;
}
// Otherwise, we're removing metadata from an instruction.
assert((hasMetadataHashEntry() ==
(getContext().pImpl->InstructionMetadata.count(this) > 0)) &&
"HasMetadata bit out of date!");
if (!hasMetadataHashEntry())
return; // Nothing to remove!
auto &Info = getContext().pImpl->InstructionMetadata[this];
// Handle removal of an existing value.
Info.erase(KindID);
if (!Info.empty())
return;
getContext().pImpl->InstructionMetadata.erase(this);
setHasMetadataHashEntry(false);
}
void Instruction::setAAMetadata(const AAMDNodes &N) {
setMetadata(LLVMContext::MD_tbaa, N.TBAA);
setMetadata(LLVMContext::MD_alias_scope, N.Scope);
setMetadata(LLVMContext::MD_noalias, N.NoAlias);
}
MDNode *Instruction::getMetadataImpl(unsigned KindID) const {
// Handle 'dbg' as a special case since it is not stored in the hash table.
if (KindID == LLVMContext::MD_dbg)
return DbgLoc.getAsMDNode();
if (!hasMetadataHashEntry())
return nullptr;
auto &Info = getContext().pImpl->InstructionMetadata[this];
assert(!Info.empty() && "bit out of sync with hash table");
return Info.lookup(KindID);
}
void Instruction::getAllMetadataImpl(
SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
Result.clear();
// Handle 'dbg' as a special case since it is not stored in the hash table.
if (DbgLoc) {
Result.push_back(
std::make_pair((unsigned)LLVMContext::MD_dbg, DbgLoc.getAsMDNode()));
if (!hasMetadataHashEntry()) return;
}
assert(hasMetadataHashEntry() &&
getContext().pImpl->InstructionMetadata.count(this) &&
"Shouldn't have called this");
const auto &Info = getContext().pImpl->InstructionMetadata.find(this)->second;
assert(!Info.empty() && "Shouldn't have called this");
Info.getAll(Result);
}
void Instruction::getAllMetadataOtherThanDebugLocImpl(
SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
Result.clear();
assert(hasMetadataHashEntry() &&
getContext().pImpl->InstructionMetadata.count(this) &&
"Shouldn't have called this");
const auto &Info = getContext().pImpl->InstructionMetadata.find(this)->second;
assert(!Info.empty() && "Shouldn't have called this");
Info.getAll(Result);
}
/// clearMetadataHashEntries - Clear all hashtable-based metadata from
/// this instruction.
void Instruction::clearMetadataHashEntries() {
assert(hasMetadataHashEntry() && "Caller should check");
getContext().pImpl->InstructionMetadata.erase(this);
setHasMetadataHashEntry(false);
}
MDNode *Function::getMetadata(unsigned KindID) const {
if (!hasMetadata())
return nullptr;
return getContext().pImpl->FunctionMetadata[this].lookup(KindID);
}
MDNode *Function::getMetadata(StringRef Kind) const {
if (!hasMetadata())
return nullptr;
return getMetadata(getContext().getMDKindID(Kind));
}
void Function::setMetadata(unsigned KindID, MDNode *MD) {
if (MD) {
if (!hasMetadata())
setHasMetadataHashEntry(true);
getContext().pImpl->FunctionMetadata[this].set(KindID, *MD);
return;
}
// Nothing to unset.
if (!hasMetadata())
return;
auto &Store = getContext().pImpl->FunctionMetadata[this];
Store.erase(KindID);
if (Store.empty())
clearMetadata();
}
void Function::setMetadata(StringRef Kind, MDNode *MD) {
if (!MD && !hasMetadata())
return;
setMetadata(getContext().getMDKindID(Kind), MD);
}
void Function::getAllMetadata(
SmallVectorImpl<std::pair<unsigned, MDNode *>> &MDs) const {
MDs.clear();
if (!hasMetadata())
return;
getContext().pImpl->FunctionMetadata[this].getAll(MDs);
}
void Function::dropUnknownMetadata(ArrayRef<unsigned> KnownIDs) {
if (!hasMetadata())
return;
if (KnownIDs.empty()) {
clearMetadata();
return;
}
SmallSet<unsigned, 5> KnownSet;
KnownSet.insert(KnownIDs.begin(), KnownIDs.end());
auto &Store = getContext().pImpl->FunctionMetadata[this];
assert(!Store.empty());
Store.remove_if([&KnownSet](const std::pair<unsigned, TrackingMDNodeRef> &I) {
return !KnownSet.count(I.first);
});
if (Store.empty())
clearMetadata();
}
void Function::clearMetadata() {
if (!hasMetadata())
return;
getContext().pImpl->FunctionMetadata.erase(this);
setHasMetadataHashEntry(false);
}
|
0 | repos/DirectXShaderCompiler/lib | repos/DirectXShaderCompiler/lib/IR/Statepoint.cpp | //===-- IR/Statepoint.cpp -- gc.statepoint utilities --- -----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/Function.h"
#include "llvm/IR/Constant.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Statepoint.h"
#include "llvm/Support/CommandLine.h"
using namespace llvm;
bool llvm::isStatepoint(const ImmutableCallSite &CS) {
if (!CS.getInstruction()) {
// This is not a call site
return false;
}
const Function *F = CS.getCalledFunction();
return (F && F->getIntrinsicID() == Intrinsic::experimental_gc_statepoint);
}
bool llvm::isStatepoint(const Value *inst) {
if (isa<InvokeInst>(inst) || isa<CallInst>(inst)) {
ImmutableCallSite CS(inst);
return isStatepoint(CS);
}
return false;
}
bool llvm::isStatepoint(const Value &inst) {
return isStatepoint(&inst);
}
bool llvm::isGCRelocate(const ImmutableCallSite &CS) {
if (!CS.getInstruction()) {
// This is not a call site
return false;
}
return isGCRelocate(CS.getInstruction());
}
bool llvm::isGCRelocate(const Value *inst) {
if (const CallInst *call = dyn_cast<CallInst>(inst)) {
if (const Function *F = call->getCalledFunction()) {
return F->getIntrinsicID() == Intrinsic::experimental_gc_relocate;
}
}
return false;
}
bool llvm::isGCResult(const ImmutableCallSite &CS) {
if (!CS.getInstruction()) {
// This is not a call site
return false;
}
return isGCResult(CS.getInstruction());
}
bool llvm::isGCResult(const Value *inst) {
if (const CallInst *call = dyn_cast<CallInst>(inst)) {
if (Function *F = call->getCalledFunction()) {
return (F->getIntrinsicID() == Intrinsic::experimental_gc_result_int ||
F->getIntrinsicID() == Intrinsic::experimental_gc_result_float ||
F->getIntrinsicID() == Intrinsic::experimental_gc_result_ptr ||
F->getIntrinsicID() == Intrinsic::experimental_gc_result);
}
}
return false;
}
|
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