| //===-- CGProfile.cpp -----------------------------------------------------===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Transforms/Instrumentation/CGProfile.h" |
| |
| #include "llvm/ADT/MapVector.h" |
| #include "llvm/Analysis/BlockFrequencyInfo.h" |
| #include "llvm/Analysis/LazyBlockFrequencyInfo.h" |
| #include "llvm/Analysis/TargetTransformInfo.h" |
| #include "llvm/IR/Constants.h" |
| #include "llvm/IR/MDBuilder.h" |
| #include "llvm/IR/PassManager.h" |
| #include "llvm/ProfileData/InstrProf.h" |
| #include "llvm/Transforms/Instrumentation.h" |
| #include <optional> |
| |
| using namespace llvm; |
| |
| static bool |
| addModuleFlags(Module &M, |
| MapVector<std::pair<Function *, Function *>, uint64_t> &Counts) { |
| if (Counts.empty()) |
| return false; |
| |
| LLVMContext &Context = M.getContext(); |
| MDBuilder MDB(Context); |
| std::vector<Metadata *> Nodes; |
| |
| for (auto E : Counts) { |
| Metadata *Vals[] = {ValueAsMetadata::get(E.first.first), |
| ValueAsMetadata::get(E.first.second), |
| MDB.createConstant(ConstantInt::get( |
| Type::getInt64Ty(Context), E.second))}; |
| Nodes.push_back(MDNode::get(Context, Vals)); |
| } |
| |
| M.addModuleFlag(Module::Append, "CG Profile", |
| MDTuple::getDistinct(Context, Nodes)); |
| return true; |
| } |
| |
| static bool runCGProfilePass(Module &M, FunctionAnalysisManager &FAM, |
| bool InLTO) { |
| MapVector<std::pair<Function *, Function *>, uint64_t> Counts; |
| InstrProfSymtab Symtab; |
| auto UpdateCounts = [&](TargetTransformInfo &TTI, Function *F, |
| Function *CalledF, uint64_t NewCount) { |
| if (NewCount == 0) |
| return; |
| if (!CalledF || !TTI.isLoweredToCall(CalledF) || |
| CalledF->hasDLLImportStorageClass()) |
| return; |
| uint64_t &Count = Counts[std::make_pair(F, CalledF)]; |
| Count = SaturatingAdd(Count, NewCount); |
| }; |
| // Ignore error here. Indirect calls are ignored if this fails. |
| (void)(bool)Symtab.create(M, InLTO); |
| for (auto &F : M) { |
| // Avoid extra cost of running passes for BFI when the function doesn't have |
| // entry count. |
| if (F.isDeclaration() || !F.getEntryCount()) |
| continue; |
| auto &BFI = FAM.getResult<BlockFrequencyAnalysis>(F); |
| if (BFI.getEntryFreq() == BlockFrequency(0)) |
| continue; |
| TargetTransformInfo &TTI = FAM.getResult<TargetIRAnalysis>(F); |
| for (auto &BB : F) { |
| std::optional<uint64_t> BBCount = BFI.getBlockProfileCount(&BB); |
| if (!BBCount) |
| continue; |
| for (auto &I : BB) { |
| CallBase *CB = dyn_cast<CallBase>(&I); |
| if (!CB) |
| continue; |
| if (CB->isIndirectCall()) { |
| InstrProfValueData ValueData[8]; |
| uint32_t ActualNumValueData; |
| uint64_t TotalC; |
| if (!getValueProfDataFromInst(*CB, IPVK_IndirectCallTarget, 8, |
| ValueData, ActualNumValueData, TotalC)) |
| continue; |
| for (const auto &VD : |
| ArrayRef<InstrProfValueData>(ValueData, ActualNumValueData)) { |
| UpdateCounts(TTI, &F, Symtab.getFunction(VD.Value), VD.Count); |
| } |
| continue; |
| } |
| UpdateCounts(TTI, &F, CB->getCalledFunction(), *BBCount); |
| } |
| } |
| } |
| |
| return addModuleFlags(M, Counts); |
| } |
| |
| PreservedAnalyses CGProfilePass::run(Module &M, ModuleAnalysisManager &MAM) { |
| FunctionAnalysisManager &FAM = |
| MAM.getResult<FunctionAnalysisManagerModuleProxy>(M).getManager(); |
| runCGProfilePass(M, FAM, InLTO); |
| |
| return PreservedAnalyses::all(); |
| } |