1 //===- InstructionNamer.cpp - Give anonymous instructions names -----------===// 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 is a little utility pass that gives instructions names, this is mostly 10 // useful when diffing the effect of an optimization because deleting an 11 // unnamed instruction can change all other instruction numbering, making the 12 // diff very noisy. 13 // 14 //===----------------------------------------------------------------------===// 15 16 #include "llvm/Transforms/Utils/InstructionNamer.h" 17 #include "llvm/IR/Function.h" 18 #include "llvm/IR/PassManager.h" 19 #include "llvm/IR/Type.h" 20 #include "llvm/InitializePasses.h" 21 #include "llvm/Pass.h" 22 #include "llvm/Transforms/Utils.h" 23 24 using namespace llvm; 25 26 namespace { 27 void nameInstructions(Function &F) { 28 for (auto &Arg : F.args()) { 29 if (!Arg.hasName()) 30 Arg.setName("arg"); 31 } 32 33 for (BasicBlock &BB : F) { 34 if (!BB.hasName()) 35 BB.setName("bb"); 36 37 for (Instruction &I : BB) { 38 if (!I.hasName() && !I.getType()->isVoidTy()) 39 I.setName("i"); 40 } 41 } 42 } 43 44 struct InstNamer : public FunctionPass { 45 static char ID; // Pass identification, replacement for typeid 46 InstNamer() : FunctionPass(ID) { 47 initializeInstNamerPass(*PassRegistry::getPassRegistry()); 48 } 49 50 void getAnalysisUsage(AnalysisUsage &Info) const override { 51 Info.setPreservesAll(); 52 } 53 54 bool runOnFunction(Function &F) override { 55 nameInstructions(F); 56 return true; 57 } 58 }; 59 60 char InstNamer::ID = 0; 61 } // namespace 62 63 INITIALIZE_PASS(InstNamer, "instnamer", 64 "Assign names to anonymous instructions", false, false) 65 char &llvm::InstructionNamerID = InstNamer::ID; 66 //===----------------------------------------------------------------------===// 67 // 68 // InstructionNamer - Give any unnamed non-void instructions "tmp" names. 69 // 70 FunctionPass *llvm::createInstructionNamerPass() { 71 return new InstNamer(); 72 } 73 74 PreservedAnalyses InstructionNamerPass::run(Function &F, 75 FunctionAnalysisManager &FAM) { 76 nameInstructions(F); 77 return PreservedAnalyses::all(); 78 } 79