text: //===- PassManagerBuilder.cpp - Build Standard Pass -----------------------===//
  //
  // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
  // See https://llvm.org/LICENSE.txt for license information.
  // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  //
  //===----------------------------------------------------------------------===//
  //
  // This file defines the PassManagerBuilder class, which is used to set up a
  // "standard" optimization sequence suitable for languages like C and C++.
  //
  //===----------------------------------------------------------------------===//
  
  #include "llvm/Transforms/IPO/PassManagerBuilder.h"
  #include "llvm-c/Transforms/PassManagerBuilder.h"
  #include "llvm/ADT/STLExtras.h"
  #include "llvm/ADT/SmallVector.h"
  #include "llvm/Analysis/CFLAndersAliasAnalysis.h"
  #include "llvm/Analysis/CFLSteensAliasAnalysis.h"
  #include "llvm/Analysis/GlobalsModRef.h"
  #include "llvm/Analysis/ScopedNoAliasAA.h"
  #include "llvm/Analysis/TargetLibraryInfo.h"
  #include "llvm/Analysis/TypeBasedAliasAnalysis.h"
  #include "llvm/IR/LegacyPassManager.h"
  #include "llvm/Support/CommandLine.h"
  #include "llvm/Support/ManagedStatic.h"
  #include "llvm/Target/CGPassBuilderOption.h"
  #include "llvm/Transforms/AggressiveInstCombine/AggressiveInstCombine.h"
  #include "llvm/Transforms/IPO.h"
  #include "llvm/Transforms/IPO/Attributor.h"
  #include "llvm/Transforms/IPO/ForceFunctionAttrs.h"
  #include "llvm/Transforms/IPO/FunctionAttrs.h"
  #include "llvm/Transforms/IPO/InferFunctionAttrs.h"
  #include "llvm/Transforms/InstCombine/InstCombine.h"
  #include "llvm/Transforms/Instrumentation.h"
  #include "llvm/Transforms/Scalar.h"
  #include "llvm/Transforms/Scalar/GVN.h"
  #include "llvm/Transforms/Scalar/LICM.h"
  #include "llvm/Transforms/Scalar/LoopUnrollPass.h"
  #include "llvm/Transforms/Scalar/SimpleLoopUnswitch.h"
  #include "llvm/Transforms/Utils.h"
  #include "llvm/Transforms/Vectorize.h"
  
  using namespace llvm;
  
  namespace llvm {
  cl::opt<bool> RunPartialInlining("enable-partial-inlining", cl::init(false),
                                   cl::Hidden, cl::ZeroOrMore,
                                   cl::desc("Run Partial inlinining pass"));
  
  static cl::opt<bool>
  UseGVNAfterVectorization("use-gvn-after-vectorization",
    cl::init(false), cl::Hidden,
    cl::desc("Run GVN instead of Early CSE after vectorization passes"));
  
  cl::opt<bool> ExtraVectorizerPasses(
      "extra-vectorizer-passes", cl::init(false), cl::Hidden,
      cl::desc("Run cleanup optimization passes after vectorization."));
  
  static cl::opt<bool>
  RunLoopRerolling("reroll-loops", cl::Hidden,
                   cl::desc("Run the loop rerolling pass"));
  
  cl::opt<bool> RunNewGVN("enable-newgvn", cl::init(false), cl::Hidden,
                          cl::desc("Run the NewGVN pass"));
  
  // Experimental option to use CFL-AA
  static cl::opt<::CFLAAType>
      UseCFLAA("use-cfl-aa", cl::init(::CFLAAType::None), cl::Hidden,
               cl::desc("Enable the new, experimental CFL alias analysis"),
               cl::values(clEnumValN(::CFLAAType::None, "none", "Disable CFL-AA"),
                          clEnumValN(::CFLAAType::Steensgaard, "steens",
                                     "Enable unification-based CFL-AA"),
                          clEnumValN(::CFLAAType::Andersen, "anders",
                                     "Enable inclusion-based CFL-AA"),
                          clEnumValN(::CFLAAType::Both, "both",
                                     "Enable both variants of CFL-AA")));
  
  cl::opt<bool> EnableLoopInterchange(
      "enable-loopinterchange", cl::init(false), cl::Hidden,
      cl::desc("Enable the experimental LoopInterchange Pass"));
  
  cl::opt<bool> EnableUnrollAndJam("enable-unroll-and-jam", cl::init(false),
                                   cl::Hidden,
                                   cl::desc("Enable Unroll And Jam Pass"));
  
  cl::opt<bool> EnableLoopFlatten("enable-loop-flatten", cl::init(false),
                                  cl::Hidden,
                                  cl::desc("Enable the LoopFlatten Pass"));
  
  cl::opt<bool> EnableDFAJumpThreading("enable-dfa-jump-thread",
                                       cl::desc("Enable DFA jump threading."),
                                       cl::init(false), cl::Hidden);
  
  static cl::opt<bool>
      EnablePrepareForThinLTO("prepare-for-thinlto", cl::init(false), cl::Hidden,
                              cl::desc("Enable preparation for ThinLTO."));
  
  static cl::opt<bool>
      EnablePerformThinLTO("perform-thinlto", cl::init(false), cl::Hidden,
                           cl::desc("Enable performing ThinLTO."));
  
  cl::opt<bool> EnableHotColdSplit("hot-cold-split", cl::init(false),
      cl::ZeroOrMore, cl::desc("Enable hot-cold splitting pass"));
  
  cl::opt<bool> EnableIROutliner("ir-outliner", cl::init(false), cl::Hidden,
      cl::desc("Enable ir outliner pass"));
  
  static cl::opt<bool> UseLoopVersioningLICM(
      "enable-loop-versioning-licm", cl::init(false), cl::Hidden,
      cl::desc("Enable the experimental Loop Versioning LICM pass"));
  
  cl::opt<bool>
      DisablePreInliner("disable-preinline", cl::init(false), cl::Hidden,
                        cl::desc("Disable pre-instrumentation inliner"));
  
  cl::opt<int> PreInlineThreshold(
      "preinline-threshold", cl::Hidden, cl::init(75), cl::ZeroOrMore,
      cl::desc("Control the amount of inlining in pre-instrumentation inliner "
               "(default = 75)"));
  
  cl::opt<bool>
      EnableGVNHoist("enable-gvn-hoist", cl::init(false), cl::ZeroOrMore,
                     cl::desc("Enable the GVN hoisting pass (default = off)"));
  
  static cl::opt<bool>
      DisableLibCallsShrinkWrap("disable-libcalls-shrinkwrap", cl::init(false),
                                cl::Hidden,
                                cl::desc("Disable shrink-wrap library calls"));
  
  cl::opt<bool>
      EnableGVNSink("enable-gvn-sink", cl::init(false), cl::ZeroOrMore,
                    cl::desc("Enable the GVN sinking pass (default = off)"));
  
  // This option is used in simplifying testing SampleFDO optimizations for
  // profile loading.
  cl::opt<bool>
      EnableCHR("enable-chr", cl::init(true), cl::Hidden,
                cl::desc("Enable control height reduction optimization (CHR)"));
  
  cl::opt<bool> FlattenedProfileUsed(
      "flattened-profile-used", cl::init(false), cl::Hidden,
      cl::desc("Indicate the sample profile being used is flattened, i.e., "
               "no inline hierachy exists in the profile. "));
  
  cl::opt<bool> EnableOrderFileInstrumentation(
      "enable-order-file-instrumentation", cl::init(false), cl::Hidden,
      cl::desc("Enable order file instrumentation (default = off)"));
  
  cl::opt<bool> EnableMatrix(
      "enable-matrix", cl::init(false), cl::Hidden,
      cl::desc("Enable lowering of the matrix intrinsics"));
  
  cl::opt<bool> EnableConstraintElimination(
      "enable-constraint-elimination", cl::init(false), cl::Hidden,
      cl::desc(
          "Enable pass to eliminate conditions based on linear constraints."));
  
  cl::opt<bool> EnableFunctionSpecialization(
      "enable-function-specialization", cl::init(false), cl::Hidden,
      cl::desc("Enable Function Specialization pass"));
  
  cl::opt<AttributorRunOption> AttributorRun(
      "attributor-enable", cl::Hidden, cl::init(AttributorRunOption::NONE),
      cl::desc("Enable the attributor inter-procedural deduction pass."),
      cl::values(clEnumValN(AttributorRunOption::ALL, "all",
                            "enable all attributor runs"),
                 clEnumValN(AttributorRunOption::MODULE, "module",
                            "enable module-wide attributor runs"),
                 clEnumValN(AttributorRunOption::CGSCC, "cgscc",
                            "enable call graph SCC attributor runs"),
                 clEnumValN(AttributorRunOption::NONE, "none",
                            "disable attributor runs")));
  
  extern cl::opt<bool> EnableKnowledgeRetention;
  } // namespace llvm
  
  PassManagerBuilder::PassManagerBuilder() {
      OptLevel = 2;
      SizeLevel = 0;
      LibraryInfo = nullptr;
      Inliner = nullptr;
      DisableUnrollLoops = false;
      SLPVectorize = false;
      LoopVectorize = true;
      LoopsInterleaved = true;
      RerollLoops = RunLoopRerolling;
      NewGVN = RunNewGVN;
      LicmMssaOptCap = SetLicmMssaOptCap;
      LicmMssaNoAccForPromotionCap = SetLicmMssaNoAccForPromotionCap;
      DisableGVNLoadPRE = false;
      ForgetAllSCEVInLoopUnroll = ForgetSCEVInLoopUnroll;
      VerifyInput = false;
      VerifyOutput = false;
      MergeFunctions = false;
      SplitColdCode = false;
      PrepareForLTO = false;
      EnablePGOInstrGen = false;
      EnablePGOCSInstrGen = false;
      EnablePGOCSInstrUse = false;
      PGOInstrGen = "";
      PGOInstrUse = "";
      PGOSampleUse = "";
      PrepareForThinLTO = EnablePrepareForThinLTO;
      PerformThinLTO = EnablePerformThinLTO;
      DivergentTarget = false;
      CallGraphProfile = true;
  }
  
  PassManagerBuilder::~PassManagerBuilder() {
    delete LibraryInfo;
    delete Inliner;
  }
  
  /// Set of global extensions, automatically added as part of the standard set.
  static ManagedStatic<
      SmallVector<std::tuple<PassManagerBuilder::ExtensionPointTy,
                             PassManagerBuilder::ExtensionFn,
                             PassManagerBuilder::GlobalExtensionID>,
                  8>>
      GlobalExtensions;
  static PassManagerBuilder::GlobalExtensionID GlobalExtensionsCounter;
  
  /// Check if GlobalExtensions is constructed and not empty.
  /// Since GlobalExtensions is a managed static, calling 'empty()' will trigger
  /// the construction of the object.
  static bool GlobalExtensionsNotEmpty() {
    return GlobalExtensions.isConstructed() && !GlobalExtensions->empty();
  }
  
  PassManagerBuilder::GlobalExtensionID
  PassManagerBuilder::addGlobalExtension(PassManagerBuilder::ExtensionPointTy Ty,
                                         PassManagerBuilder::ExtensionFn Fn) {
    auto ExtensionID = GlobalExtensionsCounter++;
    GlobalExtensions->push_back(std::make_tuple(Ty, std::move(Fn), ExtensionID));
    return ExtensionID;
  }
  
  void PassManagerBuilder::removeGlobalExtension(
      PassManagerBuilder::GlobalExtensionID ExtensionID) {
    // RegisterStandardPasses may try to call this function after GlobalExtensions
    // has already been destroyed; doing so should not generate an error.
    if (!GlobalExtensions.isConstructed())
      return;
  
    auto GlobalExtension =
        llvm::find_if(*GlobalExtensions, [ExtensionID](const auto &elem) {
          return std::get<2>(elem) == ExtensionID;
        });
    assert(GlobalExtension != GlobalExtensions->end() &&
           "The extension ID to be removed should always be valid.");
  
    GlobalExtensions->erase(GlobalExtension);
  }
  
  void PassManagerBuilder::addExtension(ExtensionPointTy Ty, ExtensionFn Fn) {
    Extensions.push_back(std::make_pair(Ty, std::move(Fn)));
  }
  
  void PassManagerBuilder::addExtensionsToPM(ExtensionPointTy ETy,
                                             legacy::PassManagerBase &PM) const {
    if (GlobalExtensionsNotEmpty()) {
      for (auto &Ext : *GlobalExtensions) {
        if (std::get<0>(Ext) == ETy)
          std::get<1>(Ext)(*this, PM);
      }
    }
    for (unsigned i = 0, e = Extensions.size(); i != e; ++i)
      if (Extensions[i].first == ETy)
        Extensions[i].second(*this, PM);
  }
  
  void PassManagerBuilder::addInitialAliasAnalysisPasses(
      legacy::PassManagerBase &PM) const {
    switch (UseCFLAA) {
    case ::CFLAAType::Steensgaard:
      PM.add(createCFLSteensAAWrapperPass());
      break;
    case ::CFLAAType::Andersen:
      PM.add(createCFLAndersAAWrapperPass());
      break;
    case ::CFLAAType::Both:
      PM.add(createCFLSteensAAWrapperPass());
      PM.add(createCFLAndersAAWrapperPass());
      break;
    default:
      break;
    }
  
    // Add TypeBasedAliasAnalysis before BasicAliasAnalysis so that
    // BasicAliasAnalysis wins if they disagree. This is intended to help
    // support "obvious" type-punning idioms.
    PM.add(createTypeBasedAAWrapperPass());
    PM.add(createScopedNoAliasAAWrapperPass());
  }
  
  void PassManagerBuilder::populateFunctionPassManager(
      legacy::FunctionPassManager &FPM) {
    addExtensionsToPM(EP_EarlyAsPossible, FPM);
  
    // Add LibraryInfo if we have some.
    if (LibraryInfo)
      FPM.add(new TargetLibraryInfoWrapperPass(*LibraryInfo));
  
    // The backends do not handle matrix intrinsics currently.
    // Make sure they are also lowered in O0.
    // FIXME: A lightweight version of the pass should run in the backend
    //        pipeline on demand.
    if (EnableMatrix && OptLevel == 0)
      FPM.add(createLowerMatrixIntrinsicsMinimalPass());
  
    if (OptLevel == 0) return;
  
    addInitialAliasAnalysisPasses(FPM);
  
    // Lower llvm.expect to metadata before attempting transforms.
    // Compare/branch metadata may alter the behavior of passes like SimplifyCFG.
    FPM.add(createLowerExpectIntrinsicPass());
    FPM.add(createCFGSimplificationPass());
    FPM.add(createSROAPass());
    FPM.add(createEarlyCSEPass());
  }
  
  void PassManagerBuilder::addFunctionSimplificationPasses(
      legacy::PassManagerBase &MPM) {
    // Start of function pass.
    // Break up aggregate allocas, using SSAUpdater.
    assert(OptLevel >= 1 && "Calling function optimizer with no optimization level!");
    MPM.add(createSROAPass());
    MPM.add(createEarlyCSEPass(true /* Enable mem-ssa. */)); // Catch trivial redundancies
    if (EnableKnowledgeRetention)
      MPM.add(createAssumeSimplifyPass());
  
    if (OptLevel > 1) {
      if (EnableGVNHoist)
        MPM.add(createGVNHoistPass());
      if (EnableGVNSink) {
        MPM.add(createGVNSinkPass());
        MPM.add(createCFGSimplificationPass(
            SimplifyCFGOptions().convertSwitchRangeToICmp(true)));
      }
    }
  
    if (EnableConstraintElimination)
      MPM.add(createConstraintEliminationPass());
  
    if (OptLevel > 1) {
      // Speculative execution if the target has divergent branches; otherwise nop.
      MPM.add(createSpeculativeExecutionIfHasBranchDivergencePass());
  
      MPM.add(createJumpThreadingPass());         // Thread jumps.
      MPM.add(createCorrelatedValuePropagationPass()); // Propagate conditionals
    }
    MPM.add(
        createCFGSimplificationPass(SimplifyCFGOptions().convertSwitchRangeToICmp(
            true))); // Merge & remove BBs
    // Combine silly seq's
    if (OptLevel > 2)
      MPM.add(createAggressiveInstCombinerPass());
    MPM.add(createInstructionCombiningPass());
    if (SizeLevel == 0 && !DisableLibCallsShrinkWrap)
      MPM.add(createLibCallsShrinkWrapPass());
    addExtensionsToPM(EP_Peephole, MPM);
  
    // TODO: Investigate the cost/benefit of tail call elimination on debugging.
    if (OptLevel > 1)
      MPM.add(createTailCallEliminationPass()); // Eliminate tail calls
    MPM.add(
        createCFGSimplificationPass(SimplifyCFGOptions().convertSwitchRangeToICmp(
            true)));                            // Merge & remove BBs
    MPM.add(createReassociatePass());           // Reassociate expressions
  
    // The matrix extension can introduce large vector operations early, which can
    // benefit from running vector-combine early on.
    if (EnableMatrix)
      MPM.add(createVectorCombinePass());
  
    // Begin the loop pass pipeline.
  
    // The simple loop unswitch pass relies on separate cleanup passes. Schedule
    // them first so when we re-process a loop they run before other loop
    // passes.
    MPM.add(createLoopInstSimplifyPass());
    MPM.add(createLoopSimplifyCFGPass());
  
    // Try to remove as much code from the loop header as possible,
    // to reduce amount of IR that will have to be duplicated. However,
    // do not perform speculative hoisting the first time as LICM
    // will destroy metadata that may not need to be destroyed if run
    // after loop rotation.
    // TODO: Investigate promotion cap for O1.
    MPM.add(createLICMPass(LicmMssaOptCap, LicmMssaNoAccForPromotionCap,
                           /*AllowSpeculation=*/false));
    // Rotate Loop - disable header duplication at -Oz
    MPM.add(createLoopRotatePass(SizeLevel == 2 ? 0 : -1, PrepareForLTO));
    // TODO: Investigate promotion cap for O1.
    MPM.add(createLICMPass(LicmMssaOptCap, LicmMssaNoAccForPromotionCap,
                           /*AllowSpeculation=*/true));
    MPM.add(createSimpleLoopUnswitchLegacyPass(OptLevel == 3));
    // FIXME: We break the loop pass pipeline here in order to do full
    // simplifycfg. Eventually loop-simplifycfg should be enhanced to replace the
    // need for this.
    MPM.add(createCFGSimplificationPass(
        SimplifyCFGOptions().convertSwitchRangeToICmp(true)));
    MPM.add(createInstructionCombiningPass());
    // We resume loop passes creating a second loop pipeline here.
    if (EnableLoopFlatten) {
      MPM.add(createLoopFlattenPass()); // Flatten loops
      MPM.add(createLoopSimplifyCFGPass());
    }
    MPM.add(createLoopIdiomPass());             // Recognize idioms like memset.
    MPM.add(createIndVarSimplifyPass());        // Canonicalize indvars
    addExtensionsToPM(EP_LateLoopOptimizations, MPM);
    MPM.add(createLoopDeletionPass());          // Delete dead loops
  
    if (EnableLoopInterchange)
      MPM.add(createLoopInterchangePass()); // Interchange loops
  
    // Unroll small loops and perform peeling.
    MPM.add(createSimpleLoopUnrollPass(OptLevel, DisableUnrollLoops,
                                       ForgetAllSCEVInLoopUnroll));
    addExtensionsToPM(EP_LoopOptimizerEnd, MPM);
    // This ends the loop pass pipelines.
  
    // Break up allocas that may now be splittable after loop unrolling.
    MPM.add(createSROAPass());
  
    if (OptLevel > 1) {
      MPM.add(createMergedLoadStoreMotionPass()); // Merge ld/st in diamonds
      MPM.add(NewGVN ? createNewGVNPass()
                     : createGVNPass(DisableGVNLoadPRE)); // Remove redundancies
    }
    MPM.add(createSCCPPass());                  // Constant prop with SCCP
  
    if (EnableConstraintElimination)
      MPM.add(createConstraintEliminationPass());
  
    // Delete dead bit computations (instcombine runs after to fold away the dead
    // computations, and then ADCE will run later to exploit any new DCE
    // opportunities that creates).
    MPM.add(createBitTrackingDCEPass());        // Delete dead bit computations
  
    // Run instcombine after redundancy elimination to exploit opportunities
    // opened up by them.
    MPM.add(createInstructionCombiningPass());
    addExtensionsToPM(EP_Peephole, MPM);
    if (OptLevel > 1) {
      if (EnableDFAJumpThreading && SizeLevel == 0)
        MPM.add(createDFAJumpThreadingPass());
  
      MPM.add(createJumpThreadingPass());         // Thread jumps
      MPM.add(createCorrelatedValuePropagationPass());
    }
    MPM.add(createAggressiveDCEPass()); // Delete dead instructions
  
    MPM.add(createMemCpyOptPass());               // Remove memcpy / form memset
    // TODO: Investigate if this is too expensive at O1.
    if (OptLevel > 1) {
      MPM.add(createDeadStoreEliminationPass());  // Delete dead stores
      MPM.add(createLICMPass(LicmMssaOptCap, LicmMssaNoAccForPromotionCap,
                             /*AllowSpeculation=*/true));
    }
  
    addExtensionsToPM(EP_ScalarOptimizerLate, MPM);
  
    if (RerollLoops)
      MPM.add(createLoopRerollPass());
  
    // Merge & remove BBs and sink & hoist common instructions.
    MPM.add(createCFGSimplificationPass(
        SimplifyCFGOptions().hoistCommonInsts(true).sinkCommonInsts(true)));
    // Clean up after everything.
    MPM.add(createInstructionCombiningPass());
    addExtensionsToPM(EP_Peephole, MPM);
  
    if (EnableCHR && OptLevel >= 3 &&
        (!PGOInstrUse.empty() || !PGOSampleUse.empty() || EnablePGOCSInstrGen))
      MPM.add(createControlHeightReductionLegacyPass());
  }
  
  /// FIXME: Should LTO cause any differences to this set of passes?
  void PassManagerBuilder::addVectorPasses(legacy::PassManagerBase &PM,
                                           bool IsFullLTO) {
    PM.add(createLoopVectorizePass(!LoopsInterleaved, !LoopVectorize));
  
    if (IsFullLTO) {
      // The vectorizer may have significantly shortened a loop body; unroll
      // again. Unroll small loops to hide loop backedge latency and saturate any
      // parallel execution resources of an out-of-order processor. We also then
      // need to clean up redundancies and loop invariant code.
      // FIXME: It would be really good to use a loop-integrated instruction
      // combiner for cleanup here so that the unrolling and LICM can be pipelined
      // across the loop nests.
      // We do UnrollAndJam in a separate LPM to ensure it happens before unroll
      if (EnableUnrollAndJam && !DisableUnrollLoops)
        PM.add(createLoopUnrollAndJamPass(OptLevel));
      PM.add(createLoopUnrollPass(OptLevel, DisableUnrollLoops,
                                  ForgetAllSCEVInLoopUnroll));
      PM.add(createWarnMissedTransformationsPass());
    }
  
    if (!IsFullLTO) {
      // Eliminate loads by forwarding stores from the previous iteration to loads
      // of the current iteration.
      PM.add(createLoopLoadEliminationPass());
    }
    // Cleanup after the loop optimization passes.
    PM.add(createInstructionCombiningPass());
  
    if (OptLevel > 1 && ExtraVectorizerPasses) {
      // At higher optimization levels, try to clean up any runtime overlap and
      // alignment checks inserted by the vectorizer. We want to track correlated
      // runtime checks for two inner loops in the same outer loop, fold any
      // common computations, hoist loop-invariant aspects out of any outer loop,
      // and unswitch the runtime checks if possible. Once hoisted, we may have
      // dead (or speculatable) control flows or more combining opportunities.
      PM.add(createEarlyCSEPass());
      PM.add(createCorrelatedValuePropagationPass());
      PM.add(createInstructionCombiningPass());
      PM.add(createLICMPass(LicmMssaOptCap, LicmMssaNoAccForPromotionCap,
                            /*AllowSpeculation=*/true));
      PM.add(createSimpleLoopUnswitchLegacyPass());
      PM.add(createCFGSimplificationPass(
          SimplifyCFGOptions().convertSwitchRangeToICmp(true)));
      PM.add(createInstructionCombiningPass());
    }
  
    // Now that we've formed fast to execute loop structures, we do further
    // optimizations. These are run afterward as they might block doing complex
    // analyses and transforms such as what are needed for loop vectorization.
  
    // Cleanup after loop vectorization, etc. Simplification passes like CVP and
    // GVN, loop transforms, and others have already run, so it's now better to
    // convert to more optimized IR using more aggressive simplify CFG options.
    // The extra sinking transform can create larger basic blocks, so do this
    // before SLP vectorization.
    PM.add(createCFGSimplificationPass(SimplifyCFGOptions()
                                           .forwardSwitchCondToPhi(true)
                                           .convertSwitchRangeToICmp(true)
                                           .convertSwitchToLookupTable(true)
                                           .needCanonicalLoops(false)
                                           .hoistCommonInsts(true)
                                           .sinkCommonInsts(true)));
  
    if (IsFullLTO) {
      PM.add(createSCCPPass());                 // Propagate exposed constants
      PM.add(createInstructionCombiningPass()); // Clean up again
      PM.add(createBitTrackingDCEPass());
    }
  
    // Optimize parallel scalar instruction chains into SIMD instructions.
    if (SLPVectorize) {
      PM.add(createSLPVectorizerPass());
      if (OptLevel > 1 && ExtraVectorizerPasses)
        PM.add(createEarlyCSEPass());
    }
  
    // Enhance/cleanup vector code.
    PM.add(createVectorCombinePass());
  
    if (!IsFullLTO) {
      addExtensionsToPM(EP_Peephole, PM);
      PM.add(createInstructionCombiningPass());
  
      if (EnableUnrollAndJam && !DisableUnrollLoops) {
        // Unroll and Jam. We do this before unroll but need to be in a separate
        // loop pass manager in order for the outer loop to be processed by
        // unroll and jam before the inner loop is unrolled.
        PM.add(createLoopUnrollAndJamPass(OptLevel));
      }
  
      // Unroll small loops
      PM.add(createLoopUnrollPass(OptLevel, DisableUnrollLoops,
                                  ForgetAllSCEVInLoopUnroll));
  
      if (!DisableUnrollLoops) {
        // LoopUnroll may generate some redundency to cleanup.
        PM.add(createInstructionCombiningPass());
  
        // Runtime unrolling will introduce runtime check in loop prologue. If the
        // unrolled loop is a inner loop, then the prologue will be inside the
        // outer loop. LICM pass can help to promote the runtime check out if the
        // checked value is loop invariant.
        PM.add(createLICMPass(LicmMssaOptCap, LicmMssaNoAccForPromotionCap,
                              /*AllowSpeculation=*/true));
      }
  
      PM.add(createWarnMissedTransformationsPass());
    }
  
    // After vectorization and unrolling, assume intrinsics may tell us more
    // about pointer alignments.
    PM.add(createAlignmentFromAssumptionsPass());
  
    if (IsFullLTO)
      PM.add(createInstructionCombiningPass());
  }
  
  void PassManagerBuilder::populateModulePassManager(
      legacy::PassManagerBase &MPM) {
    MPM.add(createAnnotation2MetadataLegacyPass());
  
    if (!PGOSampleUse.empty()) {
      MPM.add(createPruneEHPass());
      // In ThinLTO mode, when flattened profile is used, all the available
      // profile information will be annotated in PreLink phase so there is
      // no need to load the profile again in PostLink.
      if (!(FlattenedProfileUsed && PerformThinLTO))
        MPM.add(createSampleProfileLoaderPass(PGOSampleUse));
    }
  
    // Allow forcing function attributes as a debugging and tuning aid.
    MPM.add(createForceFunctionAttrsLegacyPass());
  
    // If all optimizations are disabled, just run the always-inline pass and,
    // if enabled, the function merging pass.
    if (OptLevel == 0) {
      if (Inliner) {
        MPM.add(Inliner);
        Inliner = nullptr;
      }
  
      // FIXME: The BarrierNoopPass is a HACK! The inliner pass above implicitly
      // creates a CGSCC pass manager, but we don't want to add extensions into
      // that pass manager. To prevent this we insert a no-op module pass to reset
      // the pass manager to get the same behavior as EP_OptimizerLast in non-O0
      // builds. The function merging pass is
      if (MergeFunctions)
        MPM.add(createMergeFunctionsPass());
      else if (GlobalExtensionsNotEmpty() || !Extensions.empty())
        MPM.add(createBarrierNoopPass());
  
      if (PerformThinLTO) {
        MPM.add(createLowerTypeTestsPass(nullptr, nullptr, true));
        // Drop available_externally and unreferenced globals. This is necessary
        // with ThinLTO in order to avoid leaving undefined references to dead
        // globals in the object file.
        MPM.add(createEliminateAvailableExternallyPass());
        MPM.add(createGlobalDCEPass());
      }
  
      addExtensionsToPM(EP_EnabledOnOptLevel0, MPM);
  
      if (PrepareForLTO || PrepareForThinLTO) {
        MPM.add(createCanonicalizeAliasesPass());
        // Rename anon globals to be able to export them in the summary.
        // This has to be done after we add the extensions to the pass manager
        // as there could be passes (e.g. Adddress sanitizer) which introduce
        // new unnamed globals.
        MPM.add(createNameAnonGlobalPass());
      }
  
      MPM.add(createAnnotationRemarksLegacyPass());
      return;
    }
  
    // Add LibraryInfo if we have some.
    if (LibraryInfo)
      MPM.add(new TargetLibraryInfoWrapperPass(*LibraryInfo));
  
    addInitialAliasAnalysisPasses(MPM);
  
    // For ThinLTO there are two passes of indirect call promotion. The
    // first is during the compile phase when PerformThinLTO=false and
    // intra-module indirect call targets are promoted. The second is during
    // the ThinLTO backend when PerformThinLTO=true, when we promote imported
    // inter-module indirect calls. For that we perform indirect call promotion
    // earlier in the pass pipeline, here before globalopt. Otherwise imported
    // available_externally functions look unreferenced and are removed.
    if (PerformThinLTO) {
      MPM.add(createLowerTypeTestsPass(nullptr, nullptr, true));
    }
  
    // For SamplePGO in ThinLTO compile phase, we do not want to unroll loops
    // as it will change the CFG too much to make the 2nd profile annotation
    // in backend more difficult.
    bool PrepareForThinLTOUsingPGOSampleProfile =
        PrepareForThinLTO && !PGOSampleUse.empty();
    if (PrepareForThinLTOUsingPGOSampleProfile)
      DisableUnrollLoops = true;
  
    // Infer attributes about declarations if possible.
    MPM.add(createInferFunctionAttrsLegacyPass());
  
    // Infer attributes on declarations, call sites, arguments, etc.
    if (AttributorRun & AttributorRunOption::MODULE)
      MPM.add(createAttributorLegacyPass());
  
    addExtensionsToPM(EP_ModuleOptimizerEarly, MPM);
  
    if (OptLevel > 2)
      MPM.add(createCallSiteSplittingPass());
  
    // Propage constant function arguments by specializing the functions.
    if (OptLevel > 2 && EnableFunctionSpecialization)
      MPM.add(createFunctionSpecializationPass());
  
    MPM.add(createIPSCCPPass());          // IP SCCP
    MPM.add(createCalledValuePropagationPass());
  
    MPM.add(createGlobalOptimizerPass()); // Optimize out global vars
    // Promote any localized global vars.
    MPM.add(createPromoteMemoryToRegisterPass());
  
    MPM.add(createDeadArgEliminationPass()); // Dead argument elimination
  
    MPM.add(createInstructionCombiningPass()); // Clean up after IPCP & DAE
    addExtensionsToPM(EP_Peephole, MPM);
    MPM.add(
        createCFGSimplificationPass(SimplifyCFGOptions().convertSwitchRangeToICmp(
            true))); // Clean up after IPCP & DAE
  
    // We add a module alias analysis pass here. In part due to bugs in the
    // analysis infrastructure this "works" in that the analysis stays alive
    // for the entire SCC pass run below.
    MPM.add(createGlobalsAAWrapperPass());
  
    // Start of CallGraph SCC passes.
    MPM.add(createPruneEHPass()); // Remove dead EH info
    bool RunInliner = false;
    if (Inliner) {
      MPM.add(Inliner);
      Inliner = nullptr;
      RunInliner = true;
    }
  
    // Infer attributes on declarations, call sites, arguments, etc. for an SCC.
    if (AttributorRun & AttributorRunOption::CGSCC)
      MPM.add(createAttributorCGSCCLegacyPass());
  
    // Try to perform OpenMP specific optimizations. This is a (quick!) no-op if
    // there are no OpenMP runtime calls present in the module.
    if (OptLevel > 1)
      MPM.add(createOpenMPOptCGSCCLegacyPass());
  
    MPM.add(createPostOrderFunctionAttrsLegacyPass());
    if (OptLevel > 2)
      MPM.add(createArgumentPromotionPass()); // Scalarize uninlined fn args
  
    addExtensionsToPM(EP_CGSCCOptimizerLate, MPM);
    addFunctionSimplificationPasses(MPM);
  
    // FIXME: This is a HACK! The inliner pass above implicitly creates a CGSCC
    // pass manager that we are specifically trying to avoid. To prevent this
    // we must insert a no-op module pass to reset the pass manager.
    MPM.add(createBarrierNoopPass());
  
    if (RunPartialInlining)
      MPM.add(createPartialInliningPass());
  
    if (OptLevel > 1 && !PrepareForLTO && !PrepareForThinLTO)
      // Remove avail extern fns and globals definitions if we aren't
      // compiling an object file for later LTO. For LTO we want to preserve
      // these so they are eligible for inlining at link-time. Note if they
      // are unreferenced they will be removed by GlobalDCE later, so
      // this only impacts referenced available externally globals.
      // Eventually they will be suppressed during codegen, but eliminating
      // here enables more opportunity for GlobalDCE as it may make
      // globals referenced by available external functions dead
      // and saves running remaining passes on the eliminated functions.
      MPM.add(createEliminateAvailableExternallyPass());
  
    if (EnableOrderFileInstrumentation)
      MPM.add(createInstrOrderFilePass());
  
    MPM.add(createReversePostOrderFunctionAttrsPass());
  
    // The inliner performs some kind of dead code elimination as it goes,
    // but there are cases that are not really caught by it. We might
    // at some point consider teaching the inliner about them, but it
    // is OK for now to run GlobalOpt + GlobalDCE in tandem as their
    // benefits generally outweight the cost, making the whole pipeline
    // faster.
    if (RunInliner) {
      MPM.add(createGlobalOptimizerPass());
      MPM.add(createGlobalDCEPass());
    }
  
    // If we are planning to perform ThinLTO later, let's not bloat the code with
    // unrolling/vectorization/... now. We'll first run the inliner + CGSCC passes
    // during ThinLTO and perform the rest of the optimizations afterward.
    if (PrepareForThinLTO) {
      // Ensure we perform any last passes, but do so before renaming anonymous
      // globals in case the passes add any.
      addExtensionsToPM(EP_OptimizerLast, MPM);
      MPM.add(createCanonicalizeAliasesPass());
      // Rename anon globals to be able to export them in the summary.
      MPM.add(createNameAnonGlobalPass());
      return;
    }
  
    if (PerformThinLTO)
      // Optimize globals now when performing ThinLTO, this enables more
      // optimizations later.
      MPM.add(createGlobalOptimizerPass());
  
    // Scheduling LoopVersioningLICM when inlining is over, because after that
    // we may see more accurate aliasing. Reason to run this late is that too
    // early versioning may prevent further inlining due to increase of code
    // size. By placing it just after inlining other optimizations which runs
    // later might get benefit of no-alias assumption in clone loop.
    if (UseLoopVersioningLICM) {
      MPM.add(createLoopVersioningLICMPass());    // Do LoopVersioningLICM
      MPM.add(createLICMPass(LicmMssaOptCap, LicmMssaNoAccForPromotionCap,
                             /*AllowSpeculation=*/true));
    }
  
    // We add a fresh GlobalsModRef run at this point. This is particularly
    // useful as the above will have inlined, DCE'ed, and function-attr
    // propagated everything. We should at this point have a reasonably minimal
    // and richly annotated call graph. By computing aliasing and mod/ref
    // information for all local globals here, the late loop passes and notably
    // the vectorizer will be able to use them to help recognize vectorizable
    // memory operations.
    //
    // Note that this relies on a bug in the pass manager which preserves
    // a module analysis into a function pass pipeline (and throughout it) so
    // long as the first function pass doesn't invalidate the module analysis.
    // Thus both Float2Int and LoopRotate have to preserve AliasAnalysis for
    // this to work. Fortunately, it is trivial to preserve AliasAnalysis
    // (doing nothing preserves it as it is required to be conservatively
    // correct in the face of IR changes).
    MPM.add(createGlobalsAAWrapperPass());
  
    MPM.add(createFloat2IntPass());
    MPM.add(createLowerConstantIntrinsicsPass());
  
    if (EnableMatrix) {
      MPM.add(createLowerMatrixIntrinsicsPass());
      // CSE the pointer arithmetic of the column vectors.  This allows alias
      // analysis to establish no-aliasing between loads and stores of different
      // columns of the same matrix.
      MPM.add(createEarlyCSEPass(false));
    }
  
    addExtensionsToPM(EP_VectorizerStart, MPM);
  
    // Re-rotate loops in all our loop nests. These may have fallout out of
    // rotated form due to GVN or other transformations, and the vectorizer relies
    // on the rotated form. Disable header duplication at -Oz.
    MPM.add(createLoopRotatePass(SizeLevel == 2 ? 0 : -1, PrepareForLTO));
  
    // Distribute loops to allow partial vectorization.  I.e. isolate dependences
    // into separate loop that would otherwise inhibit vectorization.  This is
    // currently only performed for loops marked with the metadata
    // llvm.loop.distribute=true or when -enable-loop-distribute is specified.
    MPM.add(createLoopDistributePass());
  
    addVectorPasses(MPM, /* IsFullLTO */ false);
  
    // FIXME: We shouldn't bother with this anymore.
    MPM.add(createStripDeadPrototypesPass()); // Get rid of dead prototypes
  
    // GlobalOpt already deletes dead functions and globals, at -O2 try a
    // late pass of GlobalDCE.  It is capable of deleting dead cycles.
    if (OptLevel > 1) {
      MPM.add(createGlobalDCEPass());         // Remove dead fns and globals.
      MPM.add(createConstantMergePass());     // Merge dup global constants
    }
  
    // See comment in the new PM for justification of scheduling splitting at
    // this stage (\ref buildModuleSimplificationPipeline).
    if ((EnableHotColdSplit || SplitColdCode) &&
        !(PrepareForLTO || PrepareForThinLTO))
      MPM.add(createHotColdSplittingPass());
  
    if (EnableIROutliner)
      MPM.add(createIROutlinerPass());
  
    if (MergeFunctions)
      MPM.add(createMergeFunctionsPass());
  
    // Add Module flag "CG Profile" based on Branch Frequency Information.
    if (CallGraphProfile)
      MPM.add(createCGProfileLegacyPass());
  
    // LoopSink pass sinks instructions hoisted by LICM, which serves as a
    // canonicalization pass that enables other optimizations. As a result,
    // LoopSink pass needs to be a very late IR pass to avoid undoing LICM
    // result too early.
    MPM.add(createLoopSinkPass());
    // Get rid of LCSSA nodes.
    MPM.add(createInstSimplifyLegacyPass());
  
    // This hoists/decomposes div/rem ops. It should run after other sink/hoist
    // passes to avoid re-sinking, but before SimplifyCFG because it can allow
    // flattening of blocks.
    MPM.add(createDivRemPairsPass());
  
    // LoopSink (and other loop passes since the last simplifyCFG) might have
    // resulted in single-entry-single-exit or empty blocks. Clean up the CFG.
    MPM.add(createCFGSimplificationPass(
        SimplifyCFGOptions().convertSwitchRangeToICmp(true)));
  
    addExtensionsToPM(EP_OptimizerLast, MPM);
  
    if (PrepareForLTO) {
      MPM.add(createCanonicalizeAliasesPass());
      // Rename anon globals to be able to handle them in the summary
      MPM.add(createNameAnonGlobalPass());
    }
  
    MPM.add(createAnnotationRemarksLegacyPass());
  }
  
  void PassManagerBuilder::addLTOOptimizationPasses(legacy::PassManagerBase &PM) {
    // Load sample profile before running the LTO optimization pipeline.
    if (!PGOSampleUse.empty()) {
      PM.add(createPruneEHPass());
      PM.add(createSampleProfileLoaderPass(PGOSampleUse));
    }
  
    // Remove unused virtual tables to improve the quality of code generated by
    // whole-program devirtualization and bitset lowering.
    PM.add(createGlobalDCEPass());
  
    // Provide AliasAnalysis services for optimizations.
    addInitialAliasAnalysisPasses(PM);
  
    // Allow forcing function attributes as a debugging and tuning aid.
    PM.add(createForceFunctionAttrsLegacyPass());
  
    // Infer attributes about declarations if possible.
    PM.add(createInferFunctionAttrsLegacyPass());
  
    if (OptLevel > 1) {
      // Split call-site with more constrained arguments.
      PM.add(createCallSiteSplittingPass());
  
      // Propage constant function arguments by specializing the functions.
      if (EnableFunctionSpecialization && OptLevel > 2)
        PM.add(createFunctionSpecializationPass());
  
      // Propagate constants at call sites into the functions they call.  This
      // opens opportunities for globalopt (and inlining) by substituting function
      // pointers passed as arguments to direct uses of functions.
      PM.add(createIPSCCPPass());
  
      // Attach metadata to indirect call sites indicating the set of functions
      // they may target at run-time. This should follow IPSCCP.
      PM.add(createCalledValuePropagationPass());
  
      // Infer attributes on declarations, call sites, arguments, etc.
      if (AttributorRun & AttributorRunOption::MODULE)
        PM.add(createAttributorLegacyPass());
    }
  
    // Infer attributes about definitions. The readnone attribute in particular is
    // required for virtual constant propagation.
    PM.add(createPostOrderFunctionAttrsLegacyPass());
    PM.add(createReversePostOrderFunctionAttrsPass());
  
    // Split globals using inrange annotations on GEP indices. This can help
    // improve the quality of generated code when virtual constant propagation or
    // control flow integrity are enabled.
    PM.add(createGlobalSplitPass());
  
    // Apply whole-program devirtualization and virtual constant propagation.
    PM.add(createWholeProgramDevirtPass(ExportSummary, nullptr));
  
    // That's all we need at opt level 1.
    if (OptLevel == 1)
      return;
  
    // Now that we internalized some globals, see if we can hack on them!
    PM.add(createGlobalOptimizerPass());
    // Promote any localized global vars.
    PM.add(createPromoteMemoryToRegisterPass());
  
    // Linking modules together can lead to duplicated global constants, only
    // keep one copy of each constant.
    PM.add(createConstantMergePass());
  
    // Remove unused arguments from functions.
    PM.add(createDeadArgEliminationPass());
  
    // Reduce the code after globalopt and ipsccp.  Both can open up significant
    // simplification opportunities, and both can propagate functions through
    // function pointers.  When this happens, we often have to resolve varargs
    // calls, etc, so let instcombine do this.
    if (OptLevel > 2)
      PM.add(createAggressiveInstCombinerPass());
    PM.add(createInstructionCombiningPass());
    addExtensionsToPM(EP_Peephole, PM);
  
    // Inline small functions
    bool RunInliner = Inliner;
    if (RunInliner) {
      PM.add(Inliner);
      Inliner = nullptr;
    }
  
    PM.add(createPruneEHPass());   // Remove dead EH info.
  
    // Infer attributes on declarations, call sites, arguments, etc. for an SCC.
    if (AttributorRun & AttributorRunOption::CGSCC)
      PM.add(createAttributorCGSCCLegacyPass());
  
    // Try to perform OpenMP specific optimizations. This is a (quick!) no-op if
    // there are no OpenMP runtime calls present in the module.
    if (OptLevel > 1)
      PM.add(createOpenMPOptCGSCCLegacyPass());
  
    // Optimize globals again if we ran the inliner.
    if (RunInliner)
      PM.add(createGlobalOptimizerPass());
    PM.add(createGlobalDCEPass()); // Remove dead functions.
  
    // If we didn't decide to inline a function, check to see if we can
    // transform it to pass arguments by value instead of by reference.
    PM.add(createArgumentPromotionPass());
  
    // The IPO passes may leave cruft around.  Clean up after them.
    PM.add(createInstructionCombiningPass());
    addExtensionsToPM(EP_Peephole, PM);
    PM.add(createJumpThreadingPass(/*FreezeSelectCond*/ true));
  
    // Break up allocas
    PM.add(createSROAPass());
  
    // LTO provides additional opportunities for tailcall elimination due to
    // link-time inlining, and visibility of nocapture attribute.
    if (OptLevel > 1)
      PM.add(createTailCallEliminationPass());
  
    // Infer attributes on declarations, call sites, arguments, etc.
    PM.add(createPostOrderFunctionAttrsLegacyPass()); // Add nocapture.
    // Run a few AA driven optimizations here and now, to cleanup the code.
    PM.add(createGlobalsAAWrapperPass()); // IP alias analysis.
  
    PM.add(createLICMPass(LicmMssaOptCap, LicmMssaNoAccForPromotionCap,
                          /*AllowSpeculation=*/true));
    PM.add(NewGVN ? createNewGVNPass()
                  : createGVNPass(DisableGVNLoadPRE)); // Remove redundancies.
    PM.add(createMemCpyOptPass());            // Remove dead memcpys.
  
    // Nuke dead stores.
    PM.add(createDeadStoreEliminationPass());
    PM.add(createMergedLoadStoreMotionPass()); // Merge ld/st in diamonds.
  
    // More loops are countable; try to optimize them.
    if (EnableLoopFlatten)
      PM.add(createLoopFlattenPass());
    PM.add(createIndVarSimplifyPass());
    PM.add(createLoopDeletionPass());
    if (EnableLoopInterchange)
      PM.add(createLoopInterchangePass());
  
    if (EnableConstraintElimination)
      PM.add(createConstraintEliminationPass());
  
    // Unroll small loops and perform peeling.
    PM.add(createSimpleLoopUnrollPass(OptLevel, DisableUnrollLoops,
                                      ForgetAllSCEVInLoopUnroll));
    PM.add(createLoopDistributePass());
  
    addVectorPasses(PM, /* IsFullLTO */ true);
  
    addExtensionsToPM(EP_Peephole, PM);
  
    PM.add(createJumpThreadingPass(/*FreezeSelectCond*/ true));
  }
  
  void PassManagerBuilder::addLateLTOOptimizationPasses(
      legacy::PassManagerBase &PM) {
    // See comment in the new PM for justification of scheduling splitting at
    // this stage (\ref buildLTODefaultPipeline).
    if (EnableHotColdSplit || SplitColdCode)
      PM.add(createHotColdSplittingPass());
  
    // Delete basic blocks, which optimization passes may have killed.
    PM.add(
        createCFGSimplificationPass(SimplifyCFGOptions().hoistCommonInsts(true)));
  
    // Drop bodies of available externally objects to improve GlobalDCE.
    PM.add(createEliminateAvailableExternallyPass());
  
    // Now that we have optimized the program, discard unreachable functions.
    PM.add(createGlobalDCEPass());
  
    // FIXME: this is profitable (for compiler time) to do at -O0 too, but
    // currently it damages debug info.
    if (MergeFunctions)
      PM.add(createMergeFunctionsPass());
  }
  
  LLVMPassManagerBuilderRef LLVMPassManagerBuilderCreate() {
    PassManagerBuilder *PMB = new PassManagerBuilder();
    return wrap(PMB);
  }
  
  void LLVMPassManagerBuilderDispose(LLVMPassManagerBuilderRef PMB) {
    PassManagerBuilder *Builder = unwrap(PMB);
    delete Builder;
  }
  
  void
  LLVMPassManagerBuilderSetOptLevel(LLVMPassManagerBuilderRef PMB,
                                    unsigned OptLevel) {
    PassManagerBuilder *Builder = unwrap(PMB);
    Builder->OptLevel = OptLevel;
  }
  
  void
  LLVMPassManagerBuilderSetSizeLevel(LLVMPassManagerBuilderRef PMB,
                                     unsigned SizeLevel) {
    PassManagerBuilder *Builder = unwrap(PMB);
    Builder->SizeLevel = SizeLevel;
  }
  
  void
  LLVMPassManagerBuilderSetDisableUnitAtATime(LLVMPassManagerBuilderRef PMB,
                                              LLVMBool Value) {
    // NOTE: The DisableUnitAtATime switch has been removed.
  }
  
  void
  LLVMPassManagerBuilderSetDisableUnrollLoops(LLVMPassManagerBuilderRef PMB,
                                              LLVMBool Value) {
    PassManagerBuilder *Builder = unwrap(PMB);
    Builder->DisableUnrollLoops = Value;
  }
  
  void
  LLVMPassManagerBuilderSetDisableSimplifyLibCalls(LLVMPassManagerBuilderRef PMB,
                                                   LLVMBool Value) {
    // NOTE: The simplify-libcalls pass has been removed.
  }
  
  void
  LLVMPassManagerBuilderUseInlinerWithThreshold(LLVMPassManagerBuilderRef PMB,
                                                unsigned Threshold) {
    PassManagerBuilder *Builder = unwrap(PMB);
    Builder->Inliner = createFunctionInliningPass(Threshold);
  }
  
  void
  LLVMPassManagerBuilderPopulateFunctionPassManager(LLVMPassManagerBuilderRef PMB,
                                                    LLVMPassManagerRef PM) {
    PassManagerBuilder *Builder = unwrap(PMB);
    legacy::FunctionPassManager *FPM = unwrap<legacy::FunctionPassManager>(PM);
    Builder->populateFunctionPassManager(*FPM);
  }
  
  void
  LLVMPassManagerBuilderPopulateModulePassManager(LLVMPassManagerBuilderRef PMB,
                                                  LLVMPassManagerRef PM) {
    PassManagerBuilder *Builder = unwrap(PMB);
    legacy::PassManagerBase *MPM = unwrap(PM);
    Builder->populateModulePassManager(*MPM);
  }
  