contrib/llvm/include/llvm/Transforms/Scalar/MemCpyOptimizer.h

   1 //===---- MemCpyOptimizer.h - memcpy optimization ---------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This pass performs various transformations related to eliminating memcpy
  11 // calls, or transforming sets of stores into memset's.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #ifndef LLVM_TRANSFORMS_SCALAR_MEMCPYOPTIMIZER_H
  16 #define LLVM_TRANSFORMS_SCALAR_MEMCPYOPTIMIZER_H
  17
  18 #include "llvm/ADT/STLExtras.h"
  19 #include "llvm/Analysis/AliasAnalysis.h"
  20 #include "llvm/Analysis/AssumptionCache.h"
  21 #include "llvm/Analysis/GlobalsModRef.h"
  22 #include "llvm/Analysis/MemoryDependenceAnalysis.h"
  23 #include "llvm/Analysis/TargetLibraryInfo.h"
  24 #include "llvm/IR/Dominators.h"
  25 #include "llvm/IR/Function.h"
  26 #include "llvm/IR/Instructions.h"
  27 #include "llvm/IR/IntrinsicInst.h"
  28 #include "llvm/IR/PassManager.h"
  29
  30 namespace llvm {
  31
  32 class MemCpyOptPass : public PassInfoMixin<MemCpyOptPass> {
  33   MemoryDependenceResults *MD = nullptr;
  34   TargetLibraryInfo *TLI = nullptr;
  35   std::function<AliasAnalysis &()> LookupAliasAnalysis;
  36   std::function<AssumptionCache &()> LookupAssumptionCache;
  37   std::function<DominatorTree &()> LookupDomTree;
  38
  39 public:
  40   MemCpyOptPass() {}
  41   PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
  42   // Glue for the old PM.
  43   bool runImpl(Function &F, MemoryDependenceResults *MD_,
  44                TargetLibraryInfo *TLI_,
  45                std::function<AliasAnalysis &()> LookupAliasAnalysis_,
  46                std::function<AssumptionCache &()> LookupAssumptionCache_,
  47                std::function<DominatorTree &()> LookupDomTree_);
  48
  49 private:
  50   // Helper functions
  51   bool processStore(StoreInst *SI, BasicBlock::iterator &BBI);
  52   bool processMemSet(MemSetInst *SI, BasicBlock::iterator &BBI);
  53   bool processMemCpy(MemCpyInst *M);
  54   bool processMemMove(MemMoveInst *M);
  55   bool performCallSlotOptzn(Instruction *cpy, Value *cpyDst, Value *cpySrc,
  56                             uint64_t cpyLen, unsigned cpyAlign, CallInst *C);
  57   bool processMemCpyMemCpyDependence(MemCpyInst *M, MemCpyInst *MDep);
  58   bool processMemSetMemCpyDependence(MemCpyInst *M, MemSetInst *MDep);
  59   bool performMemCpyToMemSetOptzn(MemCpyInst *M, MemSetInst *MDep);
  60   bool processByValArgument(CallSite CS, unsigned ArgNo);
  61   Instruction *tryMergingIntoMemset(Instruction *I, Value *StartPtr,
  62                                     Value *ByteVal);
  63
  64   bool iterateOnFunction(Function &F);
  65 };
  66 }
  67
  68 #endif // LLVM_TRANSFORMS_SCALAR_MEMCPYOPTIMIZER_H