1 //===- MemCpyOptimizer.h - memcpy optimization ------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This pass performs various transformations related to eliminating memcpy 10 // calls, or transforming sets of stores into memset's. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_TRANSFORMS_SCALAR_MEMCPYOPTIMIZER_H 15 #define LLVM_TRANSFORMS_SCALAR_MEMCPYOPTIMIZER_H 16 17 #include "llvm/IR/BasicBlock.h" 18 #include "llvm/IR/PassManager.h" 19 20 namespace llvm { 21 22 class AAResults; 23 class BatchAAResults; 24 class AssumptionCache; 25 class CallBase; 26 class CallInst; 27 class DominatorTree; 28 class Function; 29 class Instruction; 30 class LoadInst; 31 class MemCpyInst; 32 class MemMoveInst; 33 class MemorySSA; 34 class MemorySSAUpdater; 35 class MemSetInst; 36 class StoreInst; 37 class TargetLibraryInfo; 38 class Value; 39 40 class MemCpyOptPass : public PassInfoMixin<MemCpyOptPass> { 41 TargetLibraryInfo *TLI = nullptr; 42 AAResults *AA = nullptr; 43 AssumptionCache *AC = nullptr; 44 DominatorTree *DT = nullptr; 45 MemorySSA *MSSA = nullptr; 46 MemorySSAUpdater *MSSAU = nullptr; 47 48 public: 49 MemCpyOptPass() = default; 50 51 PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM); 52 53 // Glue for the old PM. 54 bool runImpl(Function &F, TargetLibraryInfo *TLI, AAResults *AA, 55 AssumptionCache *AC, DominatorTree *DT, MemorySSA *MSSA); 56 57 private: 58 // Helper functions 59 bool processStore(StoreInst *SI, BasicBlock::iterator &BBI); 60 bool processStoreOfLoad(StoreInst *SI, LoadInst *LI, const DataLayout &DL, 61 BasicBlock::iterator &BBI); 62 bool processMemSet(MemSetInst *SI, BasicBlock::iterator &BBI); 63 bool processMemCpy(MemCpyInst *M, BasicBlock::iterator &BBI); 64 bool processMemMove(MemMoveInst *M); 65 bool performCallSlotOptzn(Instruction *cpyLoad, Instruction *cpyStore, 66 Value *cpyDst, Value *cpySrc, TypeSize cpyLen, 67 Align cpyAlign, BatchAAResults &BAA, 68 std::function<CallInst *()> GetC); 69 bool processMemCpyMemCpyDependence(MemCpyInst *M, MemCpyInst *MDep, 70 BatchAAResults &BAA); 71 bool processMemSetMemCpyDependence(MemCpyInst *MemCpy, MemSetInst *MemSet, 72 BatchAAResults &BAA); 73 bool performMemCpyToMemSetOptzn(MemCpyInst *MemCpy, MemSetInst *MemSet, 74 BatchAAResults &BAA); 75 bool processByValArgument(CallBase &CB, unsigned ArgNo); 76 Instruction *tryMergingIntoMemset(Instruction *I, Value *StartPtr, 77 Value *ByteVal); 78 bool moveUp(StoreInst *SI, Instruction *P, const LoadInst *LI); 79 80 void eraseInstruction(Instruction *I); 81 bool iterateOnFunction(Function &F); 82 }; 83 84 } // end namespace llvm 85 86 #endif // LLVM_TRANSFORMS_SCALAR_MEMCPYOPTIMIZER_H 87