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 #include <cstdint> 20 #include <functional> 21 22 namespace llvm { 23 24 class AAResults; 25 class AssumptionCache; 26 class CallBase; 27 class CallInst; 28 class DominatorTree; 29 class Function; 30 class Instruction; 31 class LoadInst; 32 class MemCpyInst; 33 class MemMoveInst; 34 class MemorySSA; 35 class MemorySSAUpdater; 36 class MemSetInst; 37 class StoreInst; 38 class TargetLibraryInfo; 39 class Value; 40 41 class MemCpyOptPass : public PassInfoMixin<MemCpyOptPass> { 42 TargetLibraryInfo *TLI = nullptr; 43 AAResults *AA = nullptr; 44 AssumptionCache *AC = nullptr; 45 DominatorTree *DT = nullptr; 46 MemorySSA *MSSA = nullptr; 47 MemorySSAUpdater *MSSAU = nullptr; 48 49 public: 50 MemCpyOptPass() = default; 51 52 PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM); 53 54 // Glue for the old PM. 55 bool runImpl(Function &F, TargetLibraryInfo *TLI, AAResults *AA, 56 AssumptionCache *AC, DominatorTree *DT, MemorySSA *MSSA); 57 58 private: 59 // Helper functions 60 bool processStore(StoreInst *SI, BasicBlock::iterator &BBI); 61 bool processMemSet(MemSetInst *SI, BasicBlock::iterator &BBI); 62 bool processMemCpy(MemCpyInst *M, BasicBlock::iterator &BBI); 63 bool processMemMove(MemMoveInst *M); 64 bool performCallSlotOptzn(Instruction *cpyLoad, Instruction *cpyStore, 65 Value *cpyDst, Value *cpySrc, TypeSize cpyLen, 66 Align cpyAlign, CallInst *C); 67 bool processMemCpyMemCpyDependence(MemCpyInst *M, MemCpyInst *MDep); 68 bool processMemSetMemCpyDependence(MemCpyInst *MemCpy, MemSetInst *MemSet); 69 bool performMemCpyToMemSetOptzn(MemCpyInst *MemCpy, MemSetInst *MemSet); 70 bool processByValArgument(CallBase &CB, unsigned ArgNo); 71 Instruction *tryMergingIntoMemset(Instruction *I, Value *StartPtr, 72 Value *ByteVal); 73 bool moveUp(StoreInst *SI, Instruction *P, const LoadInst *LI); 74 75 void eraseInstruction(Instruction *I); 76 bool iterateOnFunction(Function &F); 77 }; 78 79 } // end namespace llvm 80 81 #endif // LLVM_TRANSFORMS_SCALAR_MEMCPYOPTIMIZER_H 82