//===- LazyBlockFrequencyInfo.cpp - Lazy Block Frequency Analysis ---------===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// // // This is an alternative analysis pass to BlockFrequencyInfoWrapperPass. The // difference is that with this pass the block frequencies are not computed when // the analysis pass is executed but rather when the BFI result is explicitly // requested by the analysis client. // //===----------------------------------------------------------------------===// #include "llvm/Analysis/LazyBlockFrequencyInfo.h" #include "llvm/Analysis/LazyBranchProbabilityInfo.h" #include "llvm/Analysis/LoopInfo.h" #include "llvm/IR/Dominators.h" #include "llvm/InitializePasses.h" using namespace llvm; #define DEBUG_TYPE "lazy-block-freq" INITIALIZE_PASS_BEGIN(LazyBlockFrequencyInfoPass, DEBUG_TYPE, "Lazy Block Frequency Analysis", true, true) INITIALIZE_PASS_DEPENDENCY(LazyBPIPass) INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass) INITIALIZE_PASS_END(LazyBlockFrequencyInfoPass, DEBUG_TYPE, "Lazy Block Frequency Analysis", true, true) char LazyBlockFrequencyInfoPass::ID = 0; LazyBlockFrequencyInfoPass::LazyBlockFrequencyInfoPass() : FunctionPass(ID) { initializeLazyBlockFrequencyInfoPassPass(*PassRegistry::getPassRegistry()); } void LazyBlockFrequencyInfoPass::print(raw_ostream &OS, const Module *) const { LBFI.getCalculated().print(OS); } void LazyBlockFrequencyInfoPass::getAnalysisUsage(AnalysisUsage &AU) const { LazyBranchProbabilityInfoPass::getLazyBPIAnalysisUsage(AU); // We require DT so it's available when LI is available. The LI updating code // asserts that DT is also present so if we don't make sure that we have DT // here, that assert will trigger. AU.addRequired<DominatorTreeWrapperPass>(); AU.addRequired<LoopInfoWrapperPass>(); AU.setPreservesAll(); } void LazyBlockFrequencyInfoPass::releaseMemory() { LBFI.releaseMemory(); } bool LazyBlockFrequencyInfoPass::runOnFunction(Function &F) { auto &BPIPass = getAnalysis<LazyBranchProbabilityInfoPass>(); LoopInfo &LI = getAnalysis<LoopInfoWrapperPass>().getLoopInfo(); LBFI.setAnalysis(&F, &BPIPass, &LI); return false; } void LazyBlockFrequencyInfoPass::getLazyBFIAnalysisUsage(AnalysisUsage &AU) { LazyBranchProbabilityInfoPass::getLazyBPIAnalysisUsage(AU); AU.addRequired<LazyBlockFrequencyInfoPass>(); AU.addRequired<LoopInfoWrapperPass>(); } void llvm::initializeLazyBFIPassPass(PassRegistry &Registry) { initializeLazyBPIPassPass(Registry); INITIALIZE_PASS_DEPENDENCY(LazyBlockFrequencyInfoPass); INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass); } |