text: /*===================== begin_copyright_notice ==================================
  
  Copyright (c) 2017 Intel Corporation
  
  Permission is hereby granted, free of charge, to any person obtaining a
  copy of this software and associated documentation files (the
  "Software"), to deal in the Software without restriction, including
  without limitation the rights to use, copy, modify, merge, publish,
  distribute, sublicense, and/or sell copies of the Software, and to
  permit persons to whom the Software is furnished to do so, subject to
  the following conditions:
  
  The above copyright notice and this permission notice shall be included
  in all copies or substantial portions of the Software.
  
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
  CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  
  
  ======================= end_copyright_notice ==================================*/
  
  #pragma once
  
  #include "AdaptorCommon/ImplicitArgs.hpp"
  #include "Compiler/Optimizer/OpenCLPasses/KernelArgs.hpp"
  #include "Compiler/MetaDataUtilsWrapper.h"
  #include "common/LLVMWarningsPush.hpp"
  #include <llvm/Pass.h>
  #include <llvm/IR/InstVisitor.h>
  #include <llvm/IR/Instruction.h>
  #include <llvm/Analysis/AssumptionCache.h>
  #include "common/LLVMWarningsPop.hpp"
  #include "Probe/Assertion.h"
  
  namespace IGC
  {
      // Too many stateful promotion will overwhelm the surface state
      // cache(32 entries per HDC), which will significally impact the
      // performace. Simplily disable stateful promotion after 32 args.
      constexpr uint maxPromotionCount = 32;
  
      class StatelessToStatefull : public llvm::FunctionPass, public llvm::InstVisitor<StatelessToStatefull>
      {
      public:
          typedef llvm::DenseMap<const KernelArg*, int> ArgInfoMap;
  
          static char ID;
  
          StatelessToStatefull(bool NoNegOffset = false);
  
          ~StatelessToStatefull() {}
  
          virtual void getAnalysisUsage(llvm::AnalysisUsage& AU) const override
          {
              AU.setPreservesCFG();
              AU.addRequired<MetaDataUtilsWrapper>();
              AU.addRequired<llvm::AssumptionCacheTracker>();
              AU.addRequired<CodeGenContextWrapper>();
          }
  
          virtual llvm::StringRef getPassName() const override
          {
              return "StatelessToStatefull";
          }
  
          virtual bool runOnFunction(llvm::Function& F) override;
  
          void visitLoadInst(llvm::LoadInst& I);
          void visitStoreInst(llvm::StoreInst& I);
          void visitCallInst(llvm::CallInst& I);
  
      private:
          llvm::CallInst* createBufferPtr(
              unsigned addrSpace, llvm::Constant* argNumber, llvm::Instruction* InsertBefore);
          bool pointerIsPositiveOffsetFromKernelArgument(
              llvm::Function* F, llvm::Value* V, llvm::Value*& offset, unsigned int& argNumber, const KernelArg*& kernelArg);
  
          // Check if the given gep can be traced back to any kernel argument.
          // return the kernel argument if found, otherwise return nullptr.
          // lastGep - the last gep of pointer address, nullptr if no GEP
          const KernelArg* gepIsFromKernelArgument(const llvm::PointerType& ptrType, llvm::GetElementPtrInst* gep);
  
          // check if the given pointer can be traced back to any kernel argument
          bool pointerIsFromKernelArgument(llvm::Value& ptr);
  
          bool getOffsetFromGEP(
              llvm::Function* F, llvm::SmallVector<llvm::GetElementPtrInst*, 4> GEPs,
              uint32_t argNumber, bool isImplicitArg, llvm::Value*& offset);
          llvm::Argument* getBufferOffsetArg(llvm::Function* F, uint32_t ArgNumber);
          void setPointerSizeTo32bit(int32_t AddrSpace, llvm::Module* M);
  
          void updateArgInfo(const KernelArg* KA, bool IsPositive);
          void finalizeArgInitialValue(llvm::Function* F);
  
          const KernelArg* getKernelArg(llvm::Value* Arg)
          {
              IGC_ASSERT_MESSAGE(m_pKernelArgs, "Should initialize it before use!");
              for (const KernelArg& arg : *m_pKernelArgs) {
                  if (arg.getArg() == Arg) {
                      return &arg;
                  }
              }
              return nullptr;
          }
  
          const KernelArg* getBufferOffsetKernelArg(const KernelArg* KA)
          {
              IGC_ASSERT_MESSAGE(m_pKernelArgs, "KernelArgs: should initialize it before use!");
              int argno = KA->getAssociatedArgNo();
              for (const KernelArg& arg : *m_pKernelArgs) {
                  if (arg.getArgType() == KernelArg::ArgType::IMPLICIT_BUFFER_OFFSET &&
                      arg.getAssociatedArgNo() == argno) {
                      return &arg;
                  }
              }
              return nullptr;
          }
  
          // When true, runtime can generate surface with buffer's original base (creation base)
          const bool m_hasBufferOffsetArg;
  
          // When m_hasBufferOffsetArg is true, optional buffer offset
          // can be on or off, which is indicated by this boolean flag.
          bool       m_hasOptionalBufferOffsetArg;
  
          // For historic reason, kernel ptrArgs, such as char*, short*, are assumed to
          // be aligned on DW (which is stronger than what OCL's natural alignment) in this
          // stateful optimization.  If this is not a case, this arg should be set to true!
          bool       m_hasSubDWAlignedPtrArg;
  
          // When true, every messages that are in ptrArg + offset will have offset >= 0.
          bool       m_hasPositivePointerOffset;
  
          llvm::AssumptionCacheTracker* m_ACT;
          llvm::AssumptionCache* getAC(llvm::Function* F)
          {
              return (m_ACT != nullptr ? &m_ACT->getAssumptionCache(*F)
                  : nullptr);
          }
  
          ImplicitArgs* m_pImplicitArgs;
          KernelArgs* m_pKernelArgs;
          ArgInfoMap   m_argsInfo;
          bool m_changed;
          std::unordered_set<const KernelArg*> m_promotedKernelArgs; // ptr args which have been promoted to stateful
      };
  
  }
  