1 //===- LazyBranchProbabilityInfo.cpp - Lazy Branch Probability Analysis ---===// 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 is an alternative analysis pass to BranchProbabilityInfoWrapperPass. 11 // The difference is that with this pass the branch probabilities are not 12 // computed when the analysis pass is executed but rather when the BPI results 13 // is explicitly requested by the analysis client. 14 // 15 //===----------------------------------------------------------------------===// 16 17 #include "llvm/Analysis/LazyBranchProbabilityInfo.h" 18 #include "llvm/Analysis/LoopInfo.h" 19 #include "llvm/Analysis/TargetLibraryInfo.h" 20 21 using namespace llvm; 22 23 #define DEBUG_TYPE "lazy-branch-prob" 24 25 INITIALIZE_PASS_BEGIN(LazyBranchProbabilityInfoPass, DEBUG_TYPE, 26 "Lazy Branch Probability Analysis", true, true) 27 INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass) 28 INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass) 29 INITIALIZE_PASS_END(LazyBranchProbabilityInfoPass, DEBUG_TYPE, 30 "Lazy Branch Probability Analysis", true, true) 31 32 char LazyBranchProbabilityInfoPass::ID = 0; 33 34 LazyBranchProbabilityInfoPass::LazyBranchProbabilityInfoPass() 35 : FunctionPass(ID) { 36 initializeLazyBranchProbabilityInfoPassPass(*PassRegistry::getPassRegistry()); 37 } 38 39 void LazyBranchProbabilityInfoPass::print(raw_ostream &OS, 40 const Module *) const { 41 LBPI->getCalculated().print(OS); 42 } 43 44 void LazyBranchProbabilityInfoPass::getAnalysisUsage(AnalysisUsage &AU) const { 45 AU.addRequired<LoopInfoWrapperPass>(); 46 AU.addRequired<TargetLibraryInfoWrapperPass>(); 47 AU.setPreservesAll(); 48 } 49 50 void LazyBranchProbabilityInfoPass::releaseMemory() { LBPI.reset(); } 51 52 bool LazyBranchProbabilityInfoPass::runOnFunction(Function &F) { 53 LoopInfo &LI = getAnalysis<LoopInfoWrapperPass>().getLoopInfo(); 54 TargetLibraryInfo &TLI = getAnalysis<TargetLibraryInfoWrapperPass>().getTLI(); 55 LBPI = llvm::make_unique<LazyBranchProbabilityInfo>(&F, &LI, &TLI); 56 return false; 57 } 58 59 void LazyBranchProbabilityInfoPass::getLazyBPIAnalysisUsage(AnalysisUsage &AU) { 60 AU.addRequired<LazyBranchProbabilityInfoPass>(); 61 AU.addRequired<LoopInfoWrapperPass>(); 62 AU.addRequired<TargetLibraryInfoWrapperPass>(); 63 } 64 65 void llvm::initializeLazyBPIPassPass(PassRegistry &Registry) { 66 INITIALIZE_PASS_DEPENDENCY(LazyBranchProbabilityInfoPass); 67 INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass); 68 INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass); 69 } 70