1 //===- EarlyCSE.h - Simple and fast CSE pass --------------------*- 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 /// \file 10 /// This file provides the interface for a simple, fast CSE pass. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_TRANSFORMS_SCALAR_EARLYCSE_H 15 #define LLVM_TRANSFORMS_SCALAR_EARLYCSE_H 16 17 #include "llvm/IR/PassManager.h" 18 19 namespace llvm { 20 21 class Function; 22 23 /// A simple and fast domtree-based CSE pass. 24 /// 25 /// This pass does a simple depth-first walk over the dominator tree, 26 /// eliminating trivially redundant instructions and using instsimplify to 27 /// canonicalize things as it goes. It is intended to be fast and catch obvious 28 /// cases so that instcombine and other passes are more effective. It is 29 /// expected that a later pass of GVN will catch the interesting/hard cases. 30 struct EarlyCSEPass : PassInfoMixin<EarlyCSEPass> { UseMemorySSAEarlyCSEPass31 EarlyCSEPass(bool UseMemorySSA = false) : UseMemorySSA(UseMemorySSA) {} 32 33 /// Run the pass over the function. 34 PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM); 35 void printPipeline(raw_ostream &OS, 36 function_ref<StringRef(StringRef)> MapClassName2PassName); 37 38 bool UseMemorySSA; 39 }; 40 41 } // end namespace llvm 42 43 #endif // LLVM_TRANSFORMS_SCALAR_EARLYCSE_H 44