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Diffstat (limited to 'llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp')
| -rw-r--r-- | llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp | 718 |
1 files changed, 0 insertions, 718 deletions
diff --git a/llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp b/llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp deleted file mode 100644 index 89e4cd7a0c4..00000000000 --- a/llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp +++ /dev/null @@ -1,718 +0,0 @@ -//===- PGOInstru.cpp - PGO Instrumentation --------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file implements PGO instrumentation using a minimum spanning tree based -// on the following paper. -// [1] Donald E. Knuth, Francis R. Stevenson. Optimal measurement of points -// for program frequency counts. BIT Numerical Mathematics 1973, Volume 13, -// Issue 3, pp 313-322 -// The idea of the algorithm based on the fact that for each node (except for -// the entry and exit), the sum of incoming edge counts equals the sum of -// outgoing edge counts. The count of edge on spanning tree can be derived from -// those edges not on the spanning tree. Knuth proves this method instruments -// the minimum number of edges. -// -// The minimal spanning tree here is actually a maximum weight tree -- on-tree -// edges have higher frequencies (most likely to execute). The idea is to -// instrument those less frequently executed edges which speeds up the -// instrumented binaries. -// -// This file contains two passes: -// (1) Pass PGOInstrumentationGen which instruments the IR to generate edge -// count profile, and -// (2) Pass PGOInstrumentationUse which reads the edge count profile and -// annotates the branch weight. -// These two passes are mutually exclusive, and they are called at the same -// compilation point (so they see the same IR). For PGOInstrumentationGen, -// the real work is done instrumentOneFunc(). For PGOInstrumentationUse, the -// real work in done in class PGOUseFunc and the profile is opened in module -// level and passed to each PGOUseFunc instance. -// The shared code for PGOInstrumentationGen and PGOInstrumentationUse is put -// in class FuncPGOInstrumentation. -// -// Class PGOEdge represents a CFG edge and some auxiliary information. Class -// BBInfo contains auxiliary information for a BB. These two classes are used -// in PGOGenFunc. Class PGOUseEdge and UseBBInfo are the derived class of -// PGOEdge and BBInfo, respectively. They contains extra data structure used -// in populating profile counters. -// The MST implementation is in Class CFGMST. -// -//===----------------------------------------------------------------------===// - -#include "llvm/Transforms/Instrumentation.h" -#include "llvm/ADT/Statistic.h" -#include "llvm/ADT/DenseMap.h" -#include "llvm/ADT/STLExtras.h" -#include "llvm/IR/InstIterator.h" -#include "llvm/IR/Instructions.h" -#include "llvm/IR/IntrinsicInst.h" -#include "llvm/IR/IRBuilder.h" -#include "llvm/IR/MDBuilder.h" -#include "llvm/IR/DiagnosticInfo.h" -#include "llvm/Pass.h" -#include "llvm/IR/Module.h" -#include "llvm/Support/Debug.h" -#include "llvm/Support/BranchProbability.h" -#include "llvm/Support/JamCRC.h" -#include "llvm/Transforms/Utils/BasicBlockUtils.h" -#include "llvm/ProfileData/InstrProfReader.h" -#include "llvm/Analysis/CFG.h" -#include "llvm/Analysis/BranchProbabilityInfo.h" -#include "llvm/Analysis/BlockFrequencyInfo.h" -#include <string> -#include <vector> -#include <utility> -#include "CFGMST.h" - -using namespace llvm; - -#define DEBUG_TYPE "pgo-instr" - -STATISTIC(NumOfPGOInstrument, "Number of edges instrumented."); -STATISTIC(NumOfPGOEdge, "Number of edges."); -STATISTIC(NumOfPGOBB, "Number of basic-blocks."); -STATISTIC(NumOfPGOSplit, "Number of critical edge splits."); -STATISTIC(NumOfPGOFunc, "Number of functions having valid profile counts."); -STATISTIC(NumOfPGOMismatch, "Number of functions having mismatch profile."); -STATISTIC(NumOfPGOMissing, "Number of functions without profile."); - -static cl::opt<std::string> - PGOProfileFile("pgo-profile-file", cl::init(""), cl::Hidden, - cl::value_desc("filename"), - cl::desc("Specify the path of profile data file")); - -namespace { -class PGOInstrumentationGen : public ModulePass { -public: - static char ID; - - PGOInstrumentationGen() : ModulePass(ID) { - initializePGOInstrumentationGenPass(*PassRegistry::getPassRegistry()); - } - - const char *getPassName() const override { - return "PGOInstrumentationGenPass"; - } - -private: - bool runOnModule(Module &M) override; - - void getAnalysisUsage(AnalysisUsage &AU) const override { - AU.addRequired<BlockFrequencyInfoWrapperPass>(); - AU.addRequired<BranchProbabilityInfoWrapperPass>(); - } -}; - -class PGOInstrumentationUse : public ModulePass { -public: - static char ID; - - // Provide the profile filename as the parameter. - PGOInstrumentationUse(StringRef Filename = StringRef("")) - : ModulePass(ID), ProfileFileName(Filename) { - if (!PGOProfileFile.empty()) - ProfileFileName = StringRef(PGOProfileFile); - initializePGOInstrumentationUsePass(*PassRegistry::getPassRegistry()); - } - - const char *getPassName() const override { - return "PGOInstrumentationUsePass"; - } - -private: - StringRef ProfileFileName; - std::unique_ptr<IndexedInstrProfReader> PGOReader; - bool runOnModule(Module &M) override; - - void getAnalysisUsage(AnalysisUsage &AU) const override { - AU.addRequired<BlockFrequencyInfoWrapperPass>(); - AU.addRequired<BranchProbabilityInfoWrapperPass>(); - } -}; -} // end anonymous namespace - -char PGOInstrumentationGen::ID = 0; -INITIALIZE_PASS_BEGIN(PGOInstrumentationGen, "pgo-instr-gen", - "PGO instrumentation.", false, false) -INITIALIZE_PASS_DEPENDENCY(BlockFrequencyInfoWrapperPass) -INITIALIZE_PASS_DEPENDENCY(BranchProbabilityInfoWrapperPass) -INITIALIZE_PASS_END(PGOInstrumentationGen, "pgo-instr-gen", - "PGO instrumentation.", false, false) - -ModulePass *llvm::createPGOInstrumentationGenPass() { - return new PGOInstrumentationGen(); -} - -char PGOInstrumentationUse::ID = 0; -INITIALIZE_PASS_BEGIN(PGOInstrumentationUse, "pgo-instr-use", - "Read PGO instrumentation profile.", false, false) -INITIALIZE_PASS_DEPENDENCY(BlockFrequencyInfoWrapperPass) -INITIALIZE_PASS_DEPENDENCY(BranchProbabilityInfoWrapperPass) -INITIALIZE_PASS_END(PGOInstrumentationUse, "pgo-instr-use", - "Read PGO instrumentation profile.", false, false) - -ModulePass *llvm::createPGOInstrumentationUsePass(StringRef Filename) { - return new PGOInstrumentationUse(Filename); -} - -namespace { -/// \brief An MST based instrumentation for PGO -/// -/// Implements a Minimum Spanning Tree (MST) based instrumentation for PGO -/// in the function level. -// -// This class implements the CFG edges. Note the CFG can be a multi-graph. -struct PGOEdge { - const BasicBlock *SrcBB; - const BasicBlock *DestBB; - uint64_t Weight; - bool InMST; - bool Removed; - bool IsCritical; - PGOEdge(const BasicBlock *Src, const BasicBlock *Dest, unsigned W = 1) - : SrcBB(Src), DestBB(Dest), Weight(W), InMST(false), Removed(false), - IsCritical(false) {} - // Return the information string of an edge. - const std::string infoString() const { - std::string Str = (Removed ? "-" : " "); - Str += (InMST ? " " : "*"); - Str += (IsCritical ? "c" : " "); - Str += " W=" + std::to_string(Weight); - return Str; - } -}; - -// This class stores the auxiliary information for each BB. -struct BBInfo { - BBInfo *Group; - uint32_t Index; - uint32_t Rank; - - BBInfo(unsigned IX) : Group(this), Index(IX), Rank(0) {} - - // Return the information string of this object. - const std::string infoString() const { - return "Index=" + std::to_string(Index); - } -}; - -// This class implements the CFG edges. Note the CFG can be a multi-graph. -template <class Edge, class BBInfo> class FuncPGOInstrumentation { -private: - Function &F; - void computeCFGHash(); - -public: - std::string FuncName; - GlobalVariable *FuncNameVar; - // CFG hash value for this function. - uint64_t FunctionHash; - - // The Minimum Spanning Tree of function CFG. - CFGMST<Edge, BBInfo> MST; - - // Give an edge, find the BB that will be instrumented. - // Return nullptr if there is no BB to be instrumented. - BasicBlock *getInstrBB(Edge *E); - - // Return the auxiliary BB information. - BBInfo &getBBInfo(const BasicBlock *BB) const { return MST.getBBInfo(BB); } - - // Dump edges and BB information. - void dumpInfo(std::string Str = "") const { - std::string Message = "Dump Function " + FuncName + " Hash: " + - std::to_string(FunctionHash) + "\t" + Str; - MST.dumpEdges(dbgs(), Message); - } - - FuncPGOInstrumentation(Function &Func, bool CreateGlobalVar = false, - BranchProbabilityInfo *BPI_ = nullptr, - BlockFrequencyInfo *BFI_ = nullptr) - : F(Func), FunctionHash(0), MST(F, BPI_, BFI_) { - FuncName = getPGOFuncName(F); - computeCFGHash(); - DEBUG(dumpInfo("after CFGMST")); - - NumOfPGOBB += MST.BBInfos.size(); - for (auto &Ei : MST.AllEdges) { - if (Ei->Removed) - continue; - NumOfPGOEdge++; - if (!Ei->InMST) - NumOfPGOInstrument++; - } - - if (CreateGlobalVar) - FuncNameVar = createPGOFuncNameVar(F, FuncName); - }; -}; - -// Compute Hash value for the CFG: the lower 32 bits are CRC32 of the index -// value of each BB in the CFG. The higher 32 bits record the number of edges. -template <class Edge, class BBInfo> -void FuncPGOInstrumentation<Edge, BBInfo>::computeCFGHash() { - std::vector<char> Indexes; - JamCRC JC; - for (auto &BB : F) { - const TerminatorInst *TI = BB.getTerminator(); - for (unsigned s = 0, e = TI->getNumSuccessors(); s != e; ++s) { - BasicBlock *Succ = TI->getSuccessor(s); - uint32_t Index = getBBInfo(Succ).Index; - for (int i = 0; i < 4; i++) - Indexes.push_back((char)(Index >> i)); - } - } - JC.update(Indexes); - FunctionHash = MST.AllEdges.size() << 32 | JC.getCRC(); -} - -template <class Edge, class BBInfo> -BasicBlock *FuncPGOInstrumentation<Edge, BBInfo>::getInstrBB(Edge *E) { - if (E->InMST || E->Removed) - return nullptr; - - BasicBlock *SrcBB = const_cast<BasicBlock *>(E->SrcBB); - BasicBlock *DestBB = const_cast<BasicBlock *>(E->DestBB); - // For a fake edge, instrument the real BB. - if (SrcBB == nullptr) - return DestBB; - if (DestBB == nullptr) - return SrcBB; - - // Instrument the SrcBB if it has a single successor, - // otherwise, the DestBB if this is not a critical edge. - TerminatorInst *TI = SrcBB->getTerminator(); - if (TI->getNumSuccessors() <= 1) - return SrcBB; - if (!E->IsCritical) - return DestBB; - - // For a critical edge, we have to split. Instrument the newly - // created BB. - NumOfPGOSplit++; - DEBUG(dbgs() << "Split critical edge: " << getBBInfo(SrcBB).Index << " --> " - << getBBInfo(DestBB).Index << "\n"); - unsigned SuccNum = GetSuccessorNumber(SrcBB, DestBB); - BasicBlock *InstrBB = SplitCriticalEdge(TI, SuccNum); - assert(InstrBB && "Critical edge is not split"); - - E->Removed = true; - return InstrBB; -} - -// Visit all edge and instrument the edges not in MST. -// Critical edges will be split. -static void instrumentOneFunc(Function &F, Module *M, - BranchProbabilityInfo *BPI, - BlockFrequencyInfo *BFI) { - unsigned NumCounters = 0; - FuncPGOInstrumentation<PGOEdge, BBInfo> FuncInfo(F, true, BPI, BFI); - for (auto &Ei : FuncInfo.MST.AllEdges) { - if (!Ei->InMST && !Ei->Removed) - NumCounters++; - } - - uint32_t j = 0; - for (auto &Ei : FuncInfo.MST.AllEdges) { - BasicBlock *InstrBB = FuncInfo.getInstrBB(Ei.get()); - if (!InstrBB) - continue; - - IRBuilder<> Builder(InstrBB, InstrBB->getFirstInsertionPt()); - assert(Builder.GetInsertPoint() != InstrBB->end() && - "Cannot get the Instrumentation point"); - auto *I8PtrTy = Type::getInt8PtrTy(M->getContext()); - Builder.CreateCall( - Intrinsic::getDeclaration(M, Intrinsic::instrprof_increment), - {llvm::ConstantExpr::getBitCast(FuncInfo.FuncNameVar, I8PtrTy), - Builder.getInt64(FuncInfo.FunctionHash), Builder.getInt32(NumCounters), - Builder.getInt32(j++)}); - } -} - -struct PGOUseEdge : public PGOEdge { - bool CountValid; - uint64_t CountValue; - PGOUseEdge(const BasicBlock *Src, const BasicBlock *Dest, unsigned W = 1) - : PGOEdge(Src, Dest, W), CountValid(false), CountValue(0) {} - - // Set edge count value - void setEdgeCount(uint64_t Value) { - CountValue = Value; - CountValid = true; - } - - // Return the information string for this object. - const std::string infoString() const { - if (!CountValid) - return PGOEdge::infoString(); - return PGOEdge::infoString() + " Count=" + std::to_string(CountValue); - } -}; - -typedef SmallVector<PGOUseEdge *, 2> DirectEdges; - -// This class stores the auxiliary information for each BB. -struct UseBBInfo : public BBInfo { - uint64_t CountValue; - bool CountValid; - int32_t UnknownCountInEdge; - int32_t UnknownCountOutEdge; - DirectEdges InEdges; - DirectEdges OutEdges; - UseBBInfo(unsigned IX) - : BBInfo(IX), CountValue(0), CountValid(false), UnknownCountInEdge(0), - UnknownCountOutEdge(0) {} - UseBBInfo(unsigned IX, uint64_t C) - : BBInfo(IX), CountValue(C), CountValid(true), UnknownCountInEdge(0), - UnknownCountOutEdge(0) {} - - // Set the profile count value for this BB. - void setBBInfoCount(uint64_t Value) { - CountValue = Value; - CountValid = true; - } - - // Return the information string of this object. - const std::string infoString() const { - if (!CountValid) - return BBInfo::infoString(); - return BBInfo::infoString() + " Count=" + std::to_string(CountValue); - } -}; - -// Sum up the count values for all the edges. -static uint64_t sumEdgeCount(const ArrayRef<PGOUseEdge *> Edges) { - uint64_t Total = 0; - for (auto &Ei : Edges) { - if (Ei->Removed) - continue; - Total += Ei->CountValue; - } - return Total; -} - -class PGOUseFunc { -private: - Function &F; - Module *M; - // This member stores the shared information with class PGOGenFunc. - FuncPGOInstrumentation<PGOUseEdge, UseBBInfo> FuncInfo; - - // Return the auxiliary BB information. - UseBBInfo &getBBInfo(const BasicBlock *BB) const { - return FuncInfo.getBBInfo(BB); - } - - // The maximum count value in the profile. This is only used in PGO use - // compilation. - uint64_t ProgramMaxCount; - - // Find the Instrumented BB and set the value. - void setInstrumentedCounts(const std::vector<uint64_t> &CountFromProfile); - - // Set the edge counter value for the unknown edge -- there should be only - // one unknown edge. - void setEdgeCount(DirectEdges &Edges, uint64_t Value); - - // Return FuncName string; - const std::string getFuncName() const { return FuncInfo.FuncName; } - - // Set the hot/cold inline hints based on the count values. - void applyFunctionAttributes(uint64_t EntryCount, uint64_t MaxCount) { - if (ProgramMaxCount == 0) - return; - // Threshold of the hot functions. - const BranchProbability HotFunctionThreshold(1, 100); - // Threshold of the cold functions. - const BranchProbability ColdFunctionThreshold(2, 10000); - if (EntryCount >= HotFunctionThreshold.scale(ProgramMaxCount)) - F.addFnAttr(llvm::Attribute::InlineHint); - else if (MaxCount <= ColdFunctionThreshold.scale(ProgramMaxCount)) - F.addFnAttr(llvm::Attribute::Cold); - } - -public: - PGOUseFunc(Function &Func, Module *Modu, - BranchProbabilityInfo *BPI_ = nullptr, - BlockFrequencyInfo *BFI_ = nullptr) - : F(Func), M(Modu), FuncInfo(Func, false, BPI_, BFI_) {} - - // Read counts for the instrumented BB from profile. - bool readCounters(IndexedInstrProfReader *PGOReader); - - // Populate the counts for all BBs. - void populateCounters(); - - // Set the branch weights based on the count values. - void setBranchWeights(); -}; - -// Visit all the edges and assign the count value for the instrumented -// edges and the BB. -void PGOUseFunc::setInstrumentedCounts( - const std::vector<uint64_t> &CountFromProfile) { - - // Use a worklist as we will update the vector during the iteration. - std::vector<PGOUseEdge *> WorkList; - for (auto &Ei : FuncInfo.MST.AllEdges) - WorkList.push_back(Ei.get()); - - uint32_t j = 0; - for (auto &Ei : WorkList) { - BasicBlock *InstrBB = FuncInfo.getInstrBB(Ei); - if (!InstrBB) - continue; - uint64_t CountValue = CountFromProfile[j++]; - if (!Ei->Removed) { - getBBInfo(InstrBB).setBBInfoCount(CountValue); - Ei->setEdgeCount(CountValue); - continue; - } - - // Need to add two new edges. - BasicBlock *SrcBB = const_cast<BasicBlock *>(Ei->SrcBB); - BasicBlock *DestBB = const_cast<BasicBlock *>(Ei->DestBB); - // Add new edge of SrcBB->InstrBB. - PGOUseEdge &NewEdge = FuncInfo.MST.addEdge(SrcBB, InstrBB, 0); - NewEdge.setEdgeCount(CountValue); - // Add new edge of InstrBB->DestBB. - PGOUseEdge &NewEdge1 = FuncInfo.MST.addEdge(InstrBB, DestBB, 0); - NewEdge1.setEdgeCount(CountValue); - NewEdge1.InMST = true; - getBBInfo(InstrBB).setBBInfoCount(CountValue); - } -} - -// Set the count value for the unknown edges. There should be one and only one -// unknown edge in Edges vector. -void PGOUseFunc::setEdgeCount(DirectEdges &Edges, uint64_t Value) { - for (auto &Ei : Edges) { - if (Ei->CountValid) - continue; - Ei->setEdgeCount(Value); - - getBBInfo(Ei->SrcBB).UnknownCountOutEdge--; - getBBInfo(Ei->DestBB).UnknownCountInEdge--; - return; - } - llvm_unreachable("Cannot find the unknown count edge"); -} - -// Read the profile from ProfileFileName and assign the value to the -// instrumented BB and the edges. This function also updates ProgramMaxCount. -// Return true if the profile are successfully read, and false on errors. -bool PGOUseFunc::readCounters(IndexedInstrProfReader *PGOReader) { - auto &Ctx = M->getContext(); - ErrorOr<InstrProfRecord> Result = - PGOReader->getInstrProfRecord(FuncInfo.FuncName, FuncInfo.FunctionHash); - if (std::error_code EC = Result.getError()) { - if (EC == instrprof_error::unknown_function) - NumOfPGOMissing++; - else if (EC == instrprof_error::hash_mismatch || - EC == llvm::instrprof_error::malformed) - NumOfPGOMismatch++; - - std::string Msg = EC.message() + std::string(" ") + F.getName().str(); - Ctx.diagnose( - DiagnosticInfoPGOProfile(M->getName().data(), Msg, DS_Warning)); - return false; - } - std::vector<uint64_t> &CountFromProfile = Result.get().Counts; - - NumOfPGOFunc++; - DEBUG(dbgs() << CountFromProfile.size() << " counts\n"); - uint64_t ValueSum = 0; - for (unsigned i = 0, e = CountFromProfile.size(); i < e; i++) { - DEBUG(dbgs() << " " << i << ": " << CountFromProfile[i] << "\n"); - ValueSum += CountFromProfile[i]; - } - - DEBUG(dbgs() << "SUM = " << ValueSum << "\n"); - - getBBInfo(nullptr).UnknownCountOutEdge = 2; - getBBInfo(nullptr).UnknownCountInEdge = 2; - - setInstrumentedCounts(CountFromProfile); - ProgramMaxCount = PGOReader->getMaximumFunctionCount(); - return true; -} - -// Populate the counters from instrumented BBs to all BBs. -// In the end of this operation, all BBs should have a valid count value. -void PGOUseFunc::populateCounters() { - // First set up Count variable for all BBs. - for (auto &Ei : FuncInfo.MST.AllEdges) { - if (Ei->Removed) - continue; - - const BasicBlock *SrcBB = Ei->SrcBB; - const BasicBlock *DestBB = Ei->DestBB; - UseBBInfo &SrcInfo = getBBInfo(SrcBB); - UseBBInfo &DestInfo = getBBInfo(DestBB); - SrcInfo.OutEdges.push_back(Ei.get()); - DestInfo.InEdges.push_back(Ei.get()); - SrcInfo.UnknownCountOutEdge++; - DestInfo.UnknownCountInEdge++; - - if (!Ei->CountValid) - continue; - DestInfo.UnknownCountInEdge--; - SrcInfo.UnknownCountOutEdge--; - } - - bool Changes = true; - unsigned NumPasses = 0; - while (Changes) { - NumPasses++; - Changes = false; - - // For efficient traversal, it's better to start from the end as most - // of the instrumented edges are at the end. - for (auto &BB : reverse(F)) { - UseBBInfo &Count = getBBInfo(&BB); - if (!Count.CountValid) { - if (Count.UnknownCountOutEdge == 0) { - Count.CountValue = sumEdgeCount(Count.OutEdges); - Count.CountValid = true; - Changes = true; - } else if (Count.UnknownCountInEdge == 0) { - Count.CountValue = sumEdgeCount(Count.InEdges); - Count.CountValid = true; - Changes = true; - } - } - if (Count.CountValid) { - if (Count.UnknownCountOutEdge == 1) { - uint64_t Total = Count.CountValue - sumEdgeCount(Count.OutEdges); - setEdgeCount(Count.OutEdges, Total); - Changes = true; - } - if (Count.UnknownCountInEdge == 1) { - uint64_t Total = Count.CountValue - sumEdgeCount(Count.InEdges); - setEdgeCount(Count.InEdges, Total); - Changes = true; - } - } - } - } - - DEBUG(dbgs() << "Populate counts in " << NumPasses << " passes.\n"); - // Assert every BB has a valid counter. - uint64_t FuncEntryCount = getBBInfo(&*F.begin()).CountValue; - uint64_t FuncMaxCount = FuncEntryCount; - for (auto &BB : F) { - assert(getBBInfo(&BB).CountValid && "BB count is not valid"); - uint64_t Count = getBBInfo(&BB).CountValue; - if (Count > FuncMaxCount) - FuncMaxCount = Count; - } - applyFunctionAttributes(FuncEntryCount, FuncMaxCount); - - DEBUG(FuncInfo.dumpInfo("after reading profile.")); -} - -// Assign the scaled count values to the BB with multiple out edges. -void PGOUseFunc::setBranchWeights() { - // Generate MD_prof metadata for every branch instruction. - DEBUG(dbgs() << "\nSetting branch weights.\n"); - MDBuilder MDB(M->getContext()); - for (auto &BB : F) { - TerminatorInst *TI = BB.getTerminator(); - if (TI->getNumSuccessors() < 2) - continue; - if (!isa<BranchInst>(TI) && !isa<SwitchInst>(TI)) - continue; - if (getBBInfo(&BB).CountValue == 0) - continue; - - // We have a non-zero Branch BB. - const UseBBInfo &BBCountInfo = getBBInfo(&BB); - unsigned Size = BBCountInfo.OutEdges.size(); - SmallVector<unsigned, 2> EdgeCounts(Size, 0); - uint64_t MaxCount = 0; - for (unsigned s = 0; s < Size; s++) { - const PGOUseEdge *E = BBCountInfo.OutEdges[s]; - const BasicBlock *SrcBB = E->SrcBB; - const BasicBlock *DestBB = E->DestBB; - if (DestBB == 0) - continue; - unsigned SuccNum = GetSuccessorNumber(SrcBB, DestBB); - uint64_t EdgeCount = E->CountValue; - if (EdgeCount > MaxCount) - MaxCount = EdgeCount; - EdgeCounts[SuccNum] = EdgeCount; - } - assert(MaxCount > 0 && "Bad max count"); - uint64_t Scale = calculateCountScale(MaxCount); - SmallVector<unsigned, 4> Weights; - for (const auto &ECI : EdgeCounts) - Weights.push_back(scaleBranchCount(ECI, Scale)); - - TI->setMetadata(llvm::LLVMContext::MD_prof, - MDB.createBranchWeights(Weights)); - DEBUG(dbgs() << "Weight is: "; for (const auto &W - : Weights) dbgs() - << W << " "; - dbgs() << "\n";); - } -} -} // end anonymous namespace - -bool PGOInstrumentationGen::runOnModule(Module &M) { - for (auto &F : M) { - if (F.isDeclaration()) - continue; - BranchProbabilityInfo *BPI = - &(getAnalysis<BranchProbabilityInfoWrapperPass>(F).getBPI()); - BlockFrequencyInfo *BFI = - &(getAnalysis<BlockFrequencyInfoWrapperPass>(F).getBFI()); - instrumentOneFunc(F, &M, BPI, BFI); - } - return true; -} - -static void setPGOCountOnFunc(PGOUseFunc &Func, - IndexedInstrProfReader *PGOReader) { - if (Func.readCounters(PGOReader)) { - Func.populateCounters(); - Func.setBranchWeights(); - } -} - -bool PGOInstrumentationUse::runOnModule(Module &M) { - DEBUG(dbgs() << "Read in profile counters: "); - auto &Ctx = M.getContext(); - // Read the counter array from file. - auto ReaderOrErr = IndexedInstrProfReader::create(ProfileFileName); - if (std::error_code EC = ReaderOrErr.getError()) { - Ctx.diagnose( - DiagnosticInfoPGOProfile(ProfileFileName.data(), EC.message())); - return false; - } - - PGOReader = std::move(ReaderOrErr.get()); - if (!PGOReader) { - Ctx.diagnose(DiagnosticInfoPGOProfile(ProfileFileName.data(), - "Cannot get PGOReader")); - return false; - } - - for (auto &F : M) { - if (F.isDeclaration()) - continue; - BranchProbabilityInfo *BPI = - &(getAnalysis<BranchProbabilityInfoWrapperPass>(F).getBPI()); - BlockFrequencyInfo *BFI = - &(getAnalysis<BlockFrequencyInfoWrapperPass>(F).getBFI()); - PGOUseFunc Func(F, &M, BPI, BFI); - setPGOCountOnFunc(Func, PGOReader.get()); - } - return true; -} |
