Index: include/llvm/IR/DiagnosticInfo.h =================================================================== --- include/llvm/IR/DiagnosticInfo.h +++ include/llvm/IR/DiagnosticInfo.h @@ -60,6 +60,7 @@ DK_OptimizationRemarkAnalysisAliasing, DK_OptimizationFailure, DK_MIRParser, + DK_PGOProfile, DK_FirstPluginKind }; @@ -250,6 +251,31 @@ const Twine &Msg; }; +/// Diagnostic information for the PGO profiler. +class DiagnosticInfoPGOProfile : public DiagnosticInfo { +public: + DiagnosticInfoPGOProfile(const char *FileName, const Twine &Msg, + DiagnosticSeverity Severity = DS_Error) + : DiagnosticInfo(DK_PGOProfile, Severity), FileName(FileName), Msg(Msg) {} + + /// \see DiagnosticInfo::print. + void print(DiagnosticPrinter &DP) const override; + + static bool classof(const DiagnosticInfo *DI) { + return DI->getKind() == DK_PGOProfile; + } + + const char *getFileName() const { return FileName; } + const Twine &getMsg() const { return Msg; } + +private: + /// Name of the input file associated with this diagnostic. + const char *FileName; + + /// Message to report. + const Twine &Msg; +}; + /// Common features for diagnostics dealing with optimization remarks. class DiagnosticInfoOptimizationBase : public DiagnosticInfo { public: Index: include/llvm/InitializePasses.h =================================================================== --- include/llvm/InitializePasses.h +++ include/llvm/InitializePasses.h @@ -117,6 +117,8 @@ void initializeExpandPostRAPass(PassRegistry&); void initializeAAResultsWrapperPassPass(PassRegistry &); void initializeGCOVProfilerPass(PassRegistry&); +void initializePGOInstrumentationGenPass(PassRegistry&); +void initializePGOInstrumentationUsePass(PassRegistry&); void initializeInstrProfilingPass(PassRegistry&); void initializeAddressSanitizerPass(PassRegistry&); void initializeAddressSanitizerModulePass(PassRegistry&); Index: include/llvm/LinkAllPasses.h =================================================================== --- include/llvm/LinkAllPasses.h +++ include/llvm/LinkAllPasses.h @@ -85,6 +85,8 @@ (void) llvm::createDomOnlyViewerPass(); (void) llvm::createDomViewerPass(); (void) llvm::createGCOVProfilerPass(); + (void) llvm::createPGOInstrumentationGenPass(); + (void) llvm::createPGOInstrumentationUsePass(); (void) llvm::createInstrProfilingPass(); (void) llvm::createFunctionInliningPass(); (void) llvm::createAlwaysInlinerPass(); Index: include/llvm/Transforms/Instrumentation.h =================================================================== --- include/llvm/Transforms/Instrumentation.h +++ include/llvm/Transforms/Instrumentation.h @@ -79,6 +79,11 @@ ModulePass *createGCOVProfilerPass(const GCOVOptions &Options = GCOVOptions::getDefault()); +// PGO Instrumention +ModulePass *createPGOInstrumentationGenPass(); +ModulePass * +createPGOInstrumentationUsePass(StringRef Filename = StringRef("")); + /// Options for the frontend instrumentation based profiling pass. struct InstrProfOptions { InstrProfOptions() : NoRedZone(false) {} @@ -149,6 +154,24 @@ /// protect against stack-based overflow vulnerabilities. FunctionPass *createSafeStackPass(const TargetMachine *TM = nullptr); +/// \brief Calculate what to divide by to scale counts. +/// +/// Given the maximum count, calculate a divisor that will scale all the +/// weights to strictly less than UINT32_MAX. +static inline uint64_t calculateCountScale(uint64_t MaxCount) { + return MaxCount < UINT32_MAX ? 1 : MaxCount / UINT32_MAX + 1; +} + +/// \brief Scale an individual branch count. +/// +/// Scale a 64-bit weight down to 32-bits using \c Scale. +/// +static inline uint32_t scaleBranchCount(uint64_t Count, uint64_t Scale) { + uint64_t Scaled = Count / Scale; + assert(Scaled <= UINT32_MAX && "overflow 32-bits"); + return Scaled; +} + } // End llvm namespace #endif Index: lib/IR/DiagnosticInfo.cpp =================================================================== --- lib/IR/DiagnosticInfo.cpp +++ lib/IR/DiagnosticInfo.cpp @@ -132,6 +132,12 @@ DP << getMsg(); } +void DiagnosticInfoPGOProfile::print(DiagnosticPrinter &DP) const { + if (getFileName()) + DP << getFileName() << ": "; + DP << getMsg(); +} + bool DiagnosticInfoOptimizationBase::isLocationAvailable() const { return getDebugLoc(); } Index: lib/Transforms/Instrumentation/CFGMST.h =================================================================== --- /dev/null +++ lib/Transforms/Instrumentation/CFGMST.h @@ -0,0 +1,217 @@ +//===-- CFGMST.h - Minimum Spanning Tree for CFG ----------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements a Union-find algorithm to compute Minimum Spanning Tree +// for a given CFG. +// +//===----------------------------------------------------------------------===// + +#include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/STLExtras.h" +#include "llvm/Analysis/BlockFrequencyInfo.h" +#include "llvm/Analysis/BranchProbabilityInfo.h" +#include "llvm/Analysis/CFG.h" +#include "llvm/Support/BranchProbability.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/raw_ostream.h" +#include "llvm/Transforms/Utils/BasicBlockUtils.h" +#include +#include +#include + +namespace llvm { + +#define DEBUG_TYPE "cfgmst" + +/// \brief An union-find based Minimum Spanning Tree for CFG +/// +/// Implements a Union-find algorithm to compute Minimum Spanning Tree +/// for a given CFG. +template class CFGMST { +public: + Function &F; + + // Store all the edges in CFG. It may contain some stale edges + // when Removed is set. + std::vector> AllEdges; + + // This map records the auxiliary information for each BB. + DenseMap> BBInfos; + + // Find the root group of the G and compress the path from G to the root. + BBInfo *findAndCompressGroup(BBInfo *G) { + if (G->Group != G) + G->Group = findAndCompressGroup(static_cast(G->Group)); + return static_cast(G->Group); + } + + // Union BB1 and BB2 into the same group and return true. + // Returns false if BB1 and BB2 are already in the same group. + bool unionGroups(const BasicBlock *BB1, const BasicBlock *BB2) { + BBInfo *BB1G = findAndCompressGroup(&getBBInfo(BB1)); + BBInfo *BB2G = findAndCompressGroup(&getBBInfo(BB2)); + + if (BB1G == BB2G) + return false; + + // Make the smaller rank tree a direct child or the root of high rank tree. + if (BB1G->Rank < BB2G->Rank) + BB1G->Group = BB2G; + else { + BB2G->Group = BB1G; + // If the ranks are the same, increment root of one tree by one. + if (BB1G->Rank == BB2G->Rank) + BB1G->Rank++; + } + return true; + } + + // Give BB, return the auxiliary information. + BBInfo &getBBInfo(const BasicBlock *BB) const { + auto It = BBInfos.find(BB); + assert(It->second.get() != nullptr); + return *It->second.get(); + } + + // Traverse the CFG using a stack. Find all the edges and assign the weight. + // Edges with large weight will be put into MST first so they are less likely + // to be instrumented. + void buildEdges() { + DEBUG(dbgs() << "Build Edge on " << F.getName() << "\n"); + + const BasicBlock *BB = &(F.getEntryBlock()); + uint64_t EntryWeight = (BFI != nullptr ? BFI->getEntryFreq() : 2); + // Add a fake edge to the entry. + addEdge(nullptr, BB, EntryWeight); + + // Special handling for single BB functions. + if (succ_empty(BB)) { + addEdge(BB, nullptr, EntryWeight); + return; + } + + static const uint32_t CriticalEdgeMultiplier = 1000; + + for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) { + TerminatorInst *TI = BB->getTerminator(); + uint64_t BBWeight = + (BFI != nullptr ? BFI->getBlockFreq(&*BB).getFrequency() : 2); + uint64_t Weight = 2; + if (int successors = TI->getNumSuccessors()) { + for (int i = 0; i != successors; ++i) { + BasicBlock *TargetBB = TI->getSuccessor(i); + bool Critical = isCriticalEdge(TI, i); + uint64_t scaleFactor = BBWeight; + if (Critical) { + if (scaleFactor < UINT64_MAX / CriticalEdgeMultiplier) + scaleFactor *= CriticalEdgeMultiplier; + else + scaleFactor = UINT64_MAX; + } + if (BPI != nullptr) + Weight = BPI->getEdgeProbability(&*BB, TargetBB).scale(scaleFactor); + addEdge(&*BB, TargetBB, Weight).IsCritical = Critical; + DEBUG(dbgs() << " Edge: from " << BB->getName() << " to " + << TargetBB->getName() << " w=" << Weight << "\n"); + } + } else { + addEdge(&*BB, nullptr, BBWeight); + DEBUG(dbgs() << " Edge: from " << BB->getName() << " to exit" + << " w = " << BBWeight << "\n"); + } + } + } + + // Sort CFG edges based on its weight. + void sortEdgesByWeight() { + std::stable_sort(AllEdges.begin(), AllEdges.end(), + [](const std::unique_ptr &Edge1, + const std::unique_ptr &Edge2) { + return Edge1->Weight > Edge2->Weight; + }); + } + + // Traverse all the edges and compute the Minimum Weight Spanning Tree + // using union-find algorithm. + void computeMinimumSpanningTree() { + // First, put all the critical edge with landing-pad as the Dest to MST. + // This works around the insufficient support of critical edges split + // when destination BB is a landing pad. + for (auto &Ei : AllEdges) { + if (Ei->Removed) + continue; + if (Ei->IsCritical) { + if (Ei->DestBB && Ei->DestBB->isLandingPad()) { + if (unionGroups(Ei->SrcBB, Ei->DestBB)) + Ei->InMST = true; + } + } + } + + for (auto &Ei : AllEdges) { + if (Ei->Removed) + continue; + if (unionGroups(Ei->SrcBB, Ei->DestBB)) + Ei->InMST = true; + } + } + + // Dump the Debug information about the instrumentation. + void dumpEdges(raw_ostream &OS, const Twine &Message) const { + if (!Message.str().empty()) + OS << Message << "\n"; + OS << " Number of Basic Blocks: " << BBInfos.size() << "\n"; + for (auto &BI : BBInfos) { + const BasicBlock *BB = BI.first; + OS << " BB: " << (BB == nullptr ? "FakeNode" : BB->getName()) << " " + << BI.second->infoString() << "\n"; + } + + OS << " Number of Edges: " << AllEdges.size() + << " (*: Instrument, C: CriticalEdge, -: Removed)\n"; + uint32_t Count = 0; + for (auto &EI : AllEdges) + OS << " Edge " << Count++ << ": " << getBBInfo(EI->SrcBB).Index << "-->" + << getBBInfo(EI->DestBB).Index << EI->infoString() << "\n"; + } + + // Add an edge to AllEdges with weight W. + Edge &addEdge(const BasicBlock *Src, const BasicBlock *Dest, uint64_t W) { + uint32_t Index = BBInfos.size(); + auto Iter = BBInfos.end(); + bool Inserted; + std::tie(Iter, Inserted) = BBInfos.insert(std::make_pair(Src, nullptr)); + if (Inserted) { + // Newly inserted, update the real info. + Iter->second = std::move(llvm::make_unique(Index)); + Index++; + } + std::tie(Iter, Inserted) = BBInfos.insert(std::make_pair(Dest, nullptr)); + if (Inserted) + // Newly inserted, update the real info. + Iter->second = std::move(llvm::make_unique(Index)); + AllEdges.emplace_back(new Edge(Src, Dest, W)); + return *AllEdges.back(); + } + + BranchProbabilityInfo *BPI; + BlockFrequencyInfo *BFI; + +public: + CFGMST(Function &Func, BranchProbabilityInfo *BPI_ = nullptr, + BlockFrequencyInfo *BFI_ = nullptr) + : F(Func), BPI(BPI_), BFI(BFI_) { + buildEdges(); + sortEdgesByWeight(); + computeMinimumSpanningTree(); + } +}; + +#undef DEBUG_TYPE // "cfgmst" +} // end namespace llvm Index: lib/Transforms/Instrumentation/CMakeLists.txt =================================================================== --- lib/Transforms/Instrumentation/CMakeLists.txt +++ lib/Transforms/Instrumentation/CMakeLists.txt @@ -6,6 +6,7 @@ MemorySanitizer.cpp Instrumentation.cpp InstrProfiling.cpp + PGOInstrumentation.cpp SafeStack.cpp SanitizerCoverage.cpp ThreadSanitizer.cpp Index: lib/Transforms/Instrumentation/Instrumentation.cpp =================================================================== --- lib/Transforms/Instrumentation/Instrumentation.cpp +++ lib/Transforms/Instrumentation/Instrumentation.cpp @@ -60,6 +60,8 @@ initializeAddressSanitizerModulePass(Registry); initializeBoundsCheckingPass(Registry); initializeGCOVProfilerPass(Registry); + initializePGOInstrumentationGenPass(Registry); + initializePGOInstrumentationUsePass(Registry); initializeInstrProfilingPass(Registry); initializeMemorySanitizerPass(Registry); initializeThreadSanitizerPass(Registry); Index: lib/Transforms/Instrumentation/LLVMBuild.txt =================================================================== --- lib/Transforms/Instrumentation/LLVMBuild.txt +++ lib/Transforms/Instrumentation/LLVMBuild.txt @@ -19,4 +19,4 @@ type = Library name = Instrumentation parent = Transforms -required_libraries = Analysis Core MC Support TransformUtils +required_libraries = Analysis Core MC Support TransformUtils ProfileData Index: lib/Transforms/Instrumentation/PGOInstrumentation.cpp =================================================================== --- /dev/null +++ lib/Transforms/Instrumentation/PGOInstrumentation.cpp @@ -0,0 +1,718 @@ +//===-- PGOInstrumentation.cpp - MST-based 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 (more likely to execute). The idea is to +// instrument those less frequently executed edges to reduce the runtime +// overhead of 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 weights. +// To get the precise counter information, These two passes need to invoke at +// the same compilation point (so they see the same IR). For pass +// PGOInstrumentationGen, the real work is done in instrumentOneFunc(). For +// pass 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 each BB. These two classes are used +// in pass PGOInstrumentationGen. 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 (CFGMST.h). +// +//===----------------------------------------------------------------------===// + +#include "llvm/Transforms/Instrumentation.h" +#include "CFGMST.h" +#include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/Statistic.h" +#include "llvm/Analysis/BlockFrequencyInfo.h" +#include "llvm/Analysis/BranchProbabilityInfo.h" +#include "llvm/Analysis/CFG.h" +#include "llvm/IR/DiagnosticInfo.h" +#include "llvm/IR/IRBuilder.h" +#include "llvm/IR/InstIterator.h" +#include "llvm/IR/Instructions.h" +#include "llvm/IR/IntrinsicInst.h" +#include "llvm/IR/MDBuilder.h" +#include "llvm/IR/Module.h" +#include "llvm/Pass.h" +#include "llvm/ProfileData/InstrProfReader.h" +#include "llvm/Support/BranchProbability.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/JamCRC.h" +#include "llvm/Transforms/Utils/BasicBlockUtils.h" +#include +#include +#include + +using namespace llvm; + +#define DEBUG_TYPE "pgo-instrumentation" + +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."); + +// Command line option to specify the file to read profile from. This is +// mainly used for testing. +static cl::opt + PGOTestProfileFile("pgo-test-profile-file", cl::init(""), cl::Hidden, + cl::value_desc("filename"), + cl::desc("Specify the path of profile data file. This is" + "mainly for test purpose.")); + +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(); + } +}; + +class PGOInstrumentationUse : public ModulePass { +public: + static char ID; + + // Provide the profile filename as the parameter. + PGOInstrumentationUse(std::string Filename = "") + : ModulePass(ID), ProfileFileName(Filename) { + if (!PGOTestProfileFile.empty()) + ProfileFileName = PGOTestProfileFile; + initializePGOInstrumentationUsePass(*PassRegistry::getPassRegistry()); + } + + const char *getPassName() const override { + return "PGOInstrumentationUsePass"; + } + +private: + std::string ProfileFileName; + std::unique_ptr PGOReader; + bool runOnModule(Module &M) override; + + void getAnalysisUsage(AnalysisUsage &AU) const override { + AU.addRequired(); + } +}; +} // 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.str()); +} + +namespace { +/// \brief An MST based instrumentation for PGO +/// +/// Implements a Minimum Spanning Tree (MST) based instrumentation for PGO +/// in the function level. +struct PGOEdge { + // This class implements the CFG edges. Note the CFG can be a multi-graph. + // So there might be multiple edges with same SrcBB and DestBB. + 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 { + return (Twine(Removed ? "-" : " ") + (InMST ? " " : "*") + + (IsCritical ? "c" : " ") + " W=" + Twine(Weight)).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 (Twine("Index=") + Twine(Index)).str(); + } +}; + +// This class implements the CFG edges. Note the CFG can be a multi-graph. +template 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 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 { + MST.dumpEdges(dbgs(), Twine("Dump Function ") + FuncName + " Hash: " + + Twine(FunctionHash) + "\t" + Str); + } + + 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 &E : MST.AllEdges) { + if (E->Removed) + continue; + NumOfPGOEdge++; + if (!E->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 +void FuncPGOInstrumentation::computeCFGHash() { + std::vector Indexes; + JamCRC JC; + for (auto &BB : F) { + const TerminatorInst *TI = BB.getTerminator(); + for (unsigned I = 0, E = TI->getNumSuccessors(); I != E; ++I) { + BasicBlock *Succ = TI->getSuccessor(I); + uint32_t Index = getBBInfo(Succ).Index; + for (int J = 0; J < 4; J++) + Indexes.push_back((char)(Index >> (J * 8))); + } + } + JC.update(Indexes); + FunctionHash = (uint64_t)MST.AllEdges.size() << 32 | JC.getCRC(); +} + +// Given a CFG E to be instrumented, find which BB to place the instrumented +// code. The function will split the critical edge if necessary. +template +BasicBlock *FuncPGOInstrumentation::getInstrBB(Edge *E) { + if (E->InMST || E->Removed) + return nullptr; + + BasicBlock *SrcBB = const_cast(E->SrcBB); + BasicBlock *DestBB = const_cast(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 FuncInfo(F, true, BPI, BFI); + for (auto &E : FuncInfo.MST.AllEdges) { + if (!E->InMST && !E->Removed) + NumCounters++; + } + + uint32_t I = 0; + for (auto &E : FuncInfo.MST.AllEdges) { + BasicBlock *InstrBB = FuncInfo.getInstrBB(E.get()); + if (!InstrBB) + continue; + + IRBuilder<> Builder(InstrBB, InstrBB->getFirstInsertionPt()); + assert(Builder.GetInsertPoint() != InstrBB->end() && + "Cannot get the Instrumentation point"); + Type *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(I++)}); + } +} + +// This class represents a CFG edge in profile use compilation. +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 (Twine(PGOEdge::infoString()) + " Count=" + Twine(CountValue)).str(); + } +}; + +typedef SmallVector 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 (Twine(BBInfo::infoString()) + " Count=" + Twine(CountValue)).str(); + } +}; + +// Sum up the count values for all the edges. +static uint64_t sumEdgeCount(const ArrayRef Edges) { + uint64_t Total = 0; + for (auto &E : Edges) { + if (E->Removed) + continue; + Total += E->CountValue; + } + return Total; +} + +class PGOUseFunc { +private: + Function &F; + Module *M; + // This member stores the shared information with class PGOGenFunc. + FuncPGOInstrumentation 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 &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. + // FIXME: This function should be removed once the functionality in + // the inliner is implemented. + 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 &CountFromProfile) { + + // Use a worklist as we will update the vector during the iteration. + std::vector WorkList; + for (auto &E : FuncInfo.MST.AllEdges) + WorkList.push_back(E.get()); + + uint32_t I = 0; + for (auto &E : WorkList) { + BasicBlock *InstrBB = FuncInfo.getInstrBB(E); + if (!InstrBB) + continue; + uint64_t CountValue = CountFromProfile[I++]; + if (!E->Removed) { + getBBInfo(InstrBB).setBBInfoCount(CountValue); + E->setEdgeCount(CountValue); + continue; + } + + // Need to add two new edges. + BasicBlock *SrcBB = const_cast(E->SrcBB); + BasicBlock *DestBB = const_cast(E->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 edge. There should be one and only one +// unknown edge in Edges vector. +void PGOUseFunc::setEdgeCount(DirectEdges &Edges, uint64_t Value) { + for (auto &E : Edges) { + if (E->CountValid) + continue; + E->setEdgeCount(Value); + + getBBInfo(E->SrcBB).UnknownCountOutEdge--; + getBBInfo(E->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 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 &CountFromProfile = Result.get().Counts; + + NumOfPGOFunc++; + DEBUG(dbgs() << CountFromProfile.size() << " counts\n"); + uint64_t ValueSum = 0; + for (unsigned I = 0, S = CountFromProfile.size(); I < S; 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 &E : FuncInfo.MST.AllEdges) { + if (E->Removed) + continue; + + const BasicBlock *SrcBB = E->SrcBB; + const BasicBlock *DestBB = E->DestBB; + UseBBInfo &SrcInfo = getBBInfo(SrcBB); + UseBBInfo &DestInfo = getBBInfo(DestBB); + SrcInfo.OutEdges.push_back(E.get()); + DestInfo.InEdges.push_back(E.get()); + SrcInfo.UnknownCountOutEdge++; + DestInfo.UnknownCountInEdge++; + + if (!E->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(TI) && !isa(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 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 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(F).getBPI()); + BlockFrequencyInfo *BFI = + &(getAnalysis(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(F).getBPI()); + BlockFrequencyInfo *BFI = + &(getAnalysis(F).getBFI()); + PGOUseFunc Func(F, &M, BPI, BFI); + setPGOCountOnFunc(Func, PGOReader.get()); + } + return true; +} Index: test/Transforms/PGOProfile/Inputs/branch1.proftext =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/Inputs/branch1.proftext @@ -0,0 +1,6 @@ +test_br_1 +25571299074 +2 +3 +2 + Index: test/Transforms/PGOProfile/Inputs/branch2.proftext =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/Inputs/branch2.proftext @@ -0,0 +1,6 @@ +test_br_2 +29667547796 +2 +1 +1 + Index: test/Transforms/PGOProfile/Inputs/criticaledge.proftext =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/Inputs/criticaledge.proftext @@ -0,0 +1,17 @@ +test_criticalEdge +82323253069 +8 +2 +1 +2 +2 +0 +1 +2 +1 + +:bar +12884901887 +1 +7 + Index: test/Transforms/PGOProfile/Inputs/diag.proftext =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/Inputs/diag.proftext @@ -0,0 +1,5 @@ +foo +12884999999 +1 +1 + Index: test/Transforms/PGOProfile/Inputs/landingpad.proftext =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/Inputs/landingpad.proftext @@ -0,0 +1,14 @@ +foo +59130013419 +4 +3 +1 +2 +0 + +bar +24868915205 +2 +1 +2 + Index: test/Transforms/PGOProfile/Inputs/loop1.proftext =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/Inputs/loop1.proftext @@ -0,0 +1,6 @@ +test_simple_for +34137660316 +2 +96 +4 + Index: test/Transforms/PGOProfile/Inputs/loop2.proftext =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/Inputs/loop2.proftext @@ -0,0 +1,7 @@ +test_nested_for +53929068288 +3 +33 +10 +6 + Index: test/Transforms/PGOProfile/Inputs/switch.proftext =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/Inputs/switch.proftext @@ -0,0 +1,8 @@ +test_switch +46200943743 +4 +0 +5 +2 +3 + Index: test/Transforms/PGOProfile/branch1.ll =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/branch1.ll @@ -0,0 +1,30 @@ +; RUN: opt < %s -pgo-instr-gen -S | FileCheck %s --check-prefix=GEN +; RUN: llvm-profdata merge %S/Inputs/branch1.proftext -o %T/branch1.profdata +; RUN: opt < %s -pgo-instr-use -pgo-test-profile-file=%T/branch1.profdata -S | FileCheck %s --check-prefix=USE +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +; GEN: @__llvm_profile_name_test_br_1 = private constant [9 x i8] c"test_br_1" + +define i32 @test_br_1(i32 %i) { +entry: +; GEN: entry: +; GEN-NOT: llvm.instrprof.increment + %cmp = icmp sgt i32 %i, 0 + br i1 %cmp, label %if.then, label %if.end +; USE: br i1 %cmp, label %if.then, label %if.end +; USE-SAME: !prof ![[BW_ENTRY:[0-9]+]] +; USE: ![[BW_ENTRY]] = !{!"branch_weights", i32 2, i32 1} + +if.then: +; GEN: if.then: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([9 x i8], [9 x i8]* @__llvm_profile_name_test_br_1, i32 0, i32 0), i64 25571299074, i32 2, i32 1) + %add = add nsw i32 %i, 2 + br label %if.end + +if.end: +; GEN: if.end: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([9 x i8], [9 x i8]* @__llvm_profile_name_test_br_1, i32 0, i32 0), i64 25571299074, i32 2, i32 0) + %retv = phi i32 [ %add, %if.then ], [ %i, %entry ] + ret i32 %retv +} Index: test/Transforms/PGOProfile/branch2.ll =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/branch2.ll @@ -0,0 +1,37 @@ +; RUN: opt < %s -pgo-instr-gen -S | FileCheck %s --check-prefix=GEN +; RUN: llvm-profdata merge %S/Inputs/branch2.proftext -o %T/branch2.profdata +; RUN: opt < %s -pgo-instr-use -pgo-test-profile-file=%T/branch2.profdata -S | FileCheck %s --check-prefix=USE +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +; GEN: @__llvm_profile_name_test_br_2 = private constant [9 x i8] c"test_br_2" + +define i32 @test_br_2(i32 %i) { +entry: +; GEN: entry: +; GEN-NOT: llvm.instrprof.increment + %cmp = icmp sgt i32 %i, 0 + br i1 %cmp, label %if.then, label %if.else +; USE: br i1 %cmp, label %if.then, label %if.else +; USE-SAME: !prof ![[BW_ENTRY:[0-9]+]] +; USE: ![[BW_ENTRY]] = !{!"branch_weights", i32 1, i32 1} + +if.then: +; GEN: if.then: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([9 x i8], [9 x i8]* @__llvm_profile_name_test_br_2, i32 0, i32 0), i64 29667547796, i32 2, i32 0) + %add = add nsw i32 %i, 2 + br label %if.end + +if.else: +; GEN: if.else: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([9 x i8], [9 x i8]* @__llvm_profile_name_test_br_2, i32 0, i32 0), i64 29667547796, i32 2, i32 1) + %sub = sub nsw i32 %i, 2 + br label %if.end + +if.end: +; GEN: if.end: +; GEN-NOT: llvm.instrprof.increment + %retv = phi i32 [ %add, %if.then ], [ %sub, %if.else ] + ret i32 %retv +; GEN: ret +} Index: test/Transforms/PGOProfile/criticaledge.ll =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/criticaledge.ll @@ -0,0 +1,108 @@ +; RUN: opt < %s -pgo-instr-gen -S | FileCheck %s --check-prefix=GEN +; RUN: llvm-profdata merge %S/Inputs/criticaledge.proftext -o %T/criticaledge.profdata +; RUN: opt < %s -pgo-instr-use -pgo-test-profile-file=%T/criticaledge.profdata -S | FileCheck %s --check-prefix=USE +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +; GEN: @__llvm_profile_name_test_criticalEdge = private constant [17 x i8] c"test_criticalEdge" +; GEN: @"__llvm_profile_name_:bar" = private constant [11 x i8] c":bar" + +define i32 @test_criticalEdge(i32 %i, i32 %j) { +entry: +; CHECK: entry: +; GEN-NOT: call void @llvm.instrprof.increment + switch i32 %i, label %sw.default [ + i32 1, label %sw.bb + i32 2, label %sw.bb1 + i32 3, label %sw.bb2 + i32 4, label %sw.bb2 +; CHECK: i32 3, label %entry.sw.bb2_crit_edge +; CHECK: i32 4, label %entry.sw.bb2_crit_edge1 + i32 5, label %sw.bb2 + ] +; USE: ] +; USE-SAME: !prof ![[BW_SWITCH:[0-9]+]] + +; CHECK: entry.sw.bb2_crit_edge1: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([17 x i8], [17 x i8]* @__llvm_profile_name_test_criticalEdge, i32 0, i32 0), i64 82323253069, i32 8, i32 1) +; CHECK: br label %sw.bb2 + +; CHECK: entry.sw.bb2_crit_edge: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([17 x i8], [17 x i8]* @__llvm_profile_name_test_criticalEdge, i32 0, i32 0), i64 82323253069, i32 8, i32 0) +; CHECK: br label %sw.bb2 + +sw.bb: +; GEN: sw.bb: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([17 x i8], [17 x i8]* @__llvm_profile_name_test_criticalEdge, i32 0, i32 0), i64 82323253069, i32 8, i32 5) + %call = call i32 @bar(i32 2) + br label %sw.epilog + +sw.bb1: +; GEN: sw.bb1: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([17 x i8], [17 x i8]* @__llvm_profile_name_test_criticalEdge, i32 0, i32 0), i64 82323253069, i32 8, i32 4) + %call2 = call i32 @bar(i32 1024) + br label %sw.epilog + +sw.bb2: +; GEN: sw.bb2: +; GEN-NOT: call void @llvm.instrprof.increment + %cmp = icmp eq i32 %j, 2 + br i1 %cmp, label %if.then, label %if.end +; USE: br i1 %cmp, label %if.then, label %if.end +; USE-SAME: !prof ![[BW_SW_BB2:[0-9]+]] + +if.then: +; GEN: if.then: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([17 x i8], [17 x i8]* @__llvm_profile_name_test_criticalEdge, i32 0, i32 0), i64 82323253069, i32 8, i32 2) + %call4 = call i32 @bar(i32 4) + br label %return + +if.end: +; GEN: if.end: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([17 x i8], [17 x i8]* @__llvm_profile_name_test_criticalEdge, i32 0, i32 0), i64 82323253069, i32 8, i32 3) + %call5 = call i32 @bar(i32 8) + br label %sw.epilog + +sw.default: +; GEN: sw.default: +; GEN-NOT: call void @llvm.instrprof.increment + %call6 = call i32 @bar(i32 32) + %cmp7 = icmp sgt i32 %j, 10 + br i1 %cmp7, label %if.then8, label %if.end9 +; USE: br i1 %cmp7, label %if.then8, label %if.end9 +; USE-SAME: !prof ![[BW_SW_DEFAULT:[0-9]+]] + +if.then8: +; GEN: if.then8: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([17 x i8], [17 x i8]* @__llvm_profile_name_test_criticalEdge, i32 0, i32 0), i64 82323253069, i32 8, i32 7) + %add = add nsw i32 %call6, 10 + br label %if.end9 + +if.end9: +; GEN: if.end9: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([17 x i8], [17 x i8]* @__llvm_profile_name_test_criticalEdge, i32 0, i32 0), i64 82323253069, i32 8, i32 6) + %res.0 = phi i32 [ %add, %if.then8 ], [ %call6, %sw.default ] + br label %sw.epilog + +sw.epilog: +; GEN: sw.epilog: +; GEN-NOT: call void @llvm.instrprof.increment + %res.1 = phi i32 [ %res.0, %if.end9 ], [ %call5, %if.end ], [ %call2, %sw.bb1 ], [ %call, %sw.bb ] + br label %return + +return: +; GEN: return: +; GEN-NOT: call void @llvm.instrprof.increment + %retval = phi i32 [ %res.1, %sw.epilog ], [ %call4, %if.then ] + ret i32 %retval +} + +define internal i32 @bar(i32 %i) { +entry: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([11 x i8], [11 x i8]* @"__llvm_profile_name_:bar", i32 0, i32 0), i64 12884901887, i32 1, i32 0) + ret i32 %i +} + +; USE: ![[BW_SWITCH]] = !{!"branch_weights", i32 2, i32 1, i32 0, i32 2, i32 1, i32 1} +; USE: ![[BW_SW_BB2]] = !{!"branch_weights", i32 2, i32 2} +; USE: ![[BW_SW_DEFAULT]] = !{!"branch_weights", i32 1, i32 1} Index: test/Transforms/PGOProfile/diag_mismatch.ll =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/diag_mismatch.ll @@ -0,0 +1,12 @@ +; RUN: llvm-profdata merge %S/Inputs/diag.proftext -o %T/diag.profdata +; RUN: opt < %s -pgo-instr-use -pgo-test-profile-file=%T/diag.profdata -S 2>&1 | FileCheck %s + +; CHECK: Function control flow change detected (hash mismatch) foo + +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +define i32 @foo() { +entry: + ret i32 0 +} Index: test/Transforms/PGOProfile/diag_no_funcprofdata.ll =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/diag_no_funcprofdata.ll @@ -0,0 +1,12 @@ +; RUN: llvm-profdata merge %S/Inputs/diag.proftext -o %T/diag.profdata +; RUN: opt < %s -pgo-instr-use -pgo-test-profile-file=%T/diag.profdata -S 2>&1 | FileCheck %s + +; CHECK: No profile data available for function bar + +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +define i32 @bar() { +entry: + ret i32 0 +} Index: test/Transforms/PGOProfile/diag_no_profile.ll =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/diag_no_profile.ll @@ -0,0 +1,9 @@ +; RUN: not opt < %s -pgo-instr-use -pgo-test-profile-file=%T/notexisting.profdata -S 2>&1 + +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +define i32 @foo() { +entry: + ret i32 0 +} Index: test/Transforms/PGOProfile/landingpad.ll =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/landingpad.ll @@ -0,0 +1,124 @@ +; RUN: opt < %s -pgo-instr-gen -S | FileCheck %s --check-prefix=GEN +; RUN: llvm-profdata merge %S/Inputs/landingpad.proftext -o %T/landingpad.profdata +; RUN: opt < %s -pgo-instr-use -pgo-test-profile-file=%T/landingpad.profdata -S | FileCheck %s --check-prefix=USE +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +@val = global i32 0, align 4 +@_ZTIi = external constant i8* +; GEN: @__llvm_profile_name_bar = private constant [3 x i8] c"bar" +; GEN: @__llvm_profile_name_foo = private constant [3 x i8] c"foo" + +define i32 @bar(i32 %i) { +entry: +; GEN: entry: +; GEN-NOT: call void @llvm.instrprof.increment + %rem = srem i32 %i, 3 + %tobool = icmp ne i32 %rem, 0 + br i1 %tobool, label %if.then, label %if.end +; USE: br i1 %tobool, label %if.then, label %if.end +; USE-SAME: !prof ![[BW_BAR_ENTRY:[0-9]+]] + +if.then: +; GEN: if.then: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @__llvm_profile_name_bar, i32 0, i32 0), i64 24868915205, i32 2, i32 1) + %exception = call i8* @__cxa_allocate_exception(i64 4) + %tmp = bitcast i8* %exception to i32* + store i32 %i, i32* %tmp, align 16 + call void @__cxa_throw(i8* %exception, i8* bitcast (i8** @_ZTIi to i8*), i8* null) + unreachable + +if.end: +; GEN: if.end: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @__llvm_profile_name_bar, i32 0, i32 0), i64 24868915205, i32 2, i32 0) + ret i32 0 +} + +declare i8* @__cxa_allocate_exception(i64) + +declare void @__cxa_throw(i8*, i8*, i8*) + +define i32 @foo(i32 %i) personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) { +entry: +; GEN: entry: +; GEN-NOT: call void @llvm.instrprof.increment + %rem = srem i32 %i, 2 + %tobool = icmp ne i32 %rem, 0 + br i1 %tobool, label %if.then, label %if.end +; USE: br i1 %tobool, label %if.then, label %if.end +; USE-SAME: !prof ![[BW_FOO_ENTRY:[0-9]+]] + +if.then: +; GEN: if.then: +; GEN-NOT: call void @llvm.instrprof.increment + %mul = mul nsw i32 %i, 7 + %call = invoke i32 @bar(i32 %mul) + to label %invoke.cont unwind label %lpad + +invoke.cont: +; GEN: invoke.cont: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @__llvm_profile_name_foo, i32 0, i32 0), i64 59130013419, i32 4, i32 1) + br label %if.end + +lpad: +; GEN: lpad: +; GEN-NOT: call void @llvm.instrprof.increment + %tmp = landingpad { i8*, i32 } + catch i8* bitcast (i8** @_ZTIi to i8*) + %tmp1 = extractvalue { i8*, i32 } %tmp, 0 + %tmp2 = extractvalue { i8*, i32 } %tmp, 1 + br label %catch.dispatch + +catch.dispatch: +; GEN: catch.dispatch: +; GEN-NOT: call void @llvm.instrprof.increment + %tmp3 = call i32 @llvm.eh.typeid.for(i8* bitcast (i8** @_ZTIi to i8*)) + %matches = icmp eq i32 %tmp2, %tmp3 + br i1 %matches, label %catch, label %eh.resume +; USE: br i1 %matches, label %catch, label %eh.resume +; USE-SAME: !prof ![[BW_CATCH_DISPATCH:[0-9]+]] + +catch: +; GEN: catch: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @__llvm_profile_name_foo, i32 0, i32 0), i64 59130013419, i32 4, i32 2) + %tmp4 = call i8* @__cxa_begin_catch(i8* %tmp1) + %tmp5 = bitcast i8* %tmp4 to i32* + %tmp6 = load i32, i32* %tmp5, align 4 + %tmp7 = load i32, i32* @val, align 4 + %sub = sub nsw i32 %tmp7, %tmp6 + store i32 %sub, i32* @val, align 4 + call void @__cxa_end_catch() + br label %try.cont + +try.cont: +; GEN: try.cont: +; GEN-NOT: call void @llvm.instrprof.increment + ret i32 -1 + +if.end: +; GEN: if.end: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @__llvm_profile_name_foo, i32 0, i32 0), i64 59130013419, i32 4, i32 0) + %tmp8 = load i32, i32* @val, align 4 + %add = add nsw i32 %tmp8, %i + store i32 %add, i32* @val, align 4 + br label %try.cont + +eh.resume: +; GEN: eh.resume: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @__llvm_profile_name_foo, i32 0, i32 0), i64 59130013419, i32 4, i32 3) + %lpad.val = insertvalue { i8*, i32 } undef, i8* %tmp1, 0 + %lpad.val3 = insertvalue { i8*, i32 } %lpad.val, i32 %tmp2, 1 + resume { i8*, i32 } %lpad.val3 +} + +declare i32 @__gxx_personality_v0(...) + +declare i32 @llvm.eh.typeid.for(i8*) + +declare i8* @__cxa_begin_catch(i8*) + +declare void @__cxa_end_catch() + +; USE: ![[BW_BAR_ENTRY]] = !{!"branch_weights", i32 2, i32 1} +; USE: ![[BW_FOO_ENTRY]] = !{!"branch_weights", i32 3, i32 2} +; USE: ![[BW_CATCH_DISPATCH]] = !{!"branch_weights", i32 2, i32 0} Index: test/Transforms/PGOProfile/loop1.ll =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/loop1.ll @@ -0,0 +1,42 @@ +; RUN: opt < %s -pgo-instr-gen -S | FileCheck %s --check-prefix=GEN +; RUN: llvm-profdata merge %S/Inputs/loop1.proftext -o %T/loop1.profdata +; RUN: opt < %s -pgo-instr-use -pgo-test-profile-file=%T/loop1.profdata -S | FileCheck %s --check-prefix=USE +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +; GEN: @__llvm_profile_name_test_simple_for = private constant [15 x i8] c"test_simple_for" + +define i32 @test_simple_for(i32 %n) { +entry: +; GEN: entry: +; GEN-NOT: call void @llvm.instrprof.increment + br label %for.cond + +for.cond: +; GEN: for.cond: +; GEN-NOT: call void @llvm.instrprof.increment + %i = phi i32 [ 0, %entry ], [ %inc1, %for.inc ] + %sum = phi i32 [ 1, %entry ], [ %inc, %for.inc ] + %cmp = icmp slt i32 %i, %n + br i1 %cmp, label %for.body, label %for.end +; USE: br i1 %cmp, label %for.body, label %for.end +; USE-SAME: !prof ![[BW_FOR_COND:[0-9]+]] +; USE: ![[BW_FOR_COND]] = !{!"branch_weights", i32 96, i32 4} + +for.body: +; GEN: for.body: +; GEN-NOT: call void @llvm.instrprof.increment + %inc = add nsw i32 %sum, 1 + br label %for.inc + +for.inc: +; GEN: for.inc: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([15 x i8], [15 x i8]* @__llvm_profile_name_test_simple_for, i32 0, i32 0), i64 34137660316, i32 2, i32 0) + %inc1 = add nsw i32 %i, 1 + br label %for.cond + +for.end: +; GEN: for.end: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([15 x i8], [15 x i8]* @__llvm_profile_name_test_simple_for, i32 0, i32 0), i64 34137660316, i32 2, i32 1) + ret i32 %sum +} Index: test/Transforms/PGOProfile/loop2.ll =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/loop2.ll @@ -0,0 +1,70 @@ +; RUN: opt < %s -pgo-instr-gen -S | FileCheck %s --check-prefix=GEN +; RUN: llvm-profdata merge %S/Inputs/loop2.proftext -o %T/loop2.profdata +; RUN: opt < %s -pgo-instr-use -pgo-test-profile-file=%T/loop2.profdata -S | FileCheck %s --check-prefix=USE +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +; GEN: @__llvm_profile_name_test_nested_for = private constant [15 x i8] c"test_nested_for" + +define i32 @test_nested_for(i32 %r, i32 %s) { +entry: +; GEN: entry: +; GEN-NOT: call void @llvm.instrprof.increment + br label %for.cond.outer + +for.cond.outer: +; GEN: for.cond.outer: +; GEN-NOT: call void @llvm.instrprof.increment + %i.0 = phi i32 [ 0, %entry ], [ %inc.2, %for.inc.outer ] + %sum.0 = phi i32 [ 1, %entry ], [ %sum.1, %for.inc.outer ] + %cmp = icmp slt i32 %i.0, %r + br i1 %cmp, label %for.body.outer, label %for.end.outer +; USE: br i1 %cmp, label %for.body.outer, label %for.end.outer +; USE-SAME: !prof ![[BW_FOR_COND_OUTER:[0-9]+]] + +for.body.outer: +; GEN: for.body.outer: +; GEN-NOT: call void @llvm.instrprof.increment + br label %for.cond.inner + +for.cond.inner: +; GEN: for.cond.inner: +; GEN-NOT: call void @llvm.instrprof.increment + %j.0 = phi i32 [ 0, %for.body.outer ], [ %inc.1, %for.inc.inner ] + %sum.1 = phi i32 [ %sum.0, %for.body.outer ], [ %inc, %for.inc.inner ] + %cmp2 = icmp slt i32 %j.0, %s + br i1 %cmp2, label %for.body.inner, label %for.end.inner +; USE: br i1 %cmp2, label %for.body.inner, label %for.end.inner +; USE-SAME: !prof ![[BW_FOR_COND_INNER:[0-9]+]] + +for.body.inner: +; GEN: for.body.inner: +; GEN-NOT: call void @llvm.instrprof.increment + %inc = add nsw i32 %sum.1, 1 + br label %for.inc.inner + +for.inc.inner: +; GEN: for.inc.inner: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([15 x i8], [15 x i8]* @__llvm_profile_name_test_nested_for, i32 0, i32 0), i64 53929068288, i32 3, i32 0) + %inc.1 = add nsw i32 %j.0, 1 + br label %for.cond.inner + +for.end.inner: +; GEN: for.end.inner: + br label %for.inc.outer + +for.inc.outer: +; GEN: for.inc.outer: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([15 x i8], [15 x i8]* @__llvm_profile_name_test_nested_for, i32 0, i32 0), i64 53929068288, i32 3, i32 1) + %inc.2 = add nsw i32 %i.0, 1 + br label %for.cond.outer + +for.end.outer: +; GEN: for.end.outer: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([15 x i8], [15 x i8]* @__llvm_profile_name_test_nested_for, i32 0, i32 0), i64 53929068288, i32 3, i32 2) + ret i32 %sum.0 +} + +; USE-DAG: ![[BW_FOR_COND_OUTER]] = !{!"branch_weights", i32 10, i32 6} +; USE-DAG: ![[BW_FOR_COND_INNER]] = !{!"branch_weights", i32 33, i32 10} + Index: test/Transforms/PGOProfile/single_bb.ll =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/single_bb.ll @@ -0,0 +1,12 @@ +; RUN: opt < %s -pgo-instr-gen -S | FileCheck %s --check-prefix=GEN +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +; GEN: @__llvm_profile_name_single_bb = private constant [9 x i8] c"single_bb" + +define i32 @single_bb() { +entry: +; GEN: entry: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([9 x i8], [9 x i8]* @__llvm_profile_name_single_bb, i32 0, i32 0), i64 12884901887, i32 1, i32 0) + ret i32 0 +} Index: test/Transforms/PGOProfile/switch.ll =================================================================== --- /dev/null +++ test/Transforms/PGOProfile/switch.ll @@ -0,0 +1,47 @@ +; RUN: opt < %s -pgo-instr-gen -S | FileCheck %s --check-prefix=GEN +; RUN: llvm-profdata merge %S/Inputs/switch.proftext -o %T/switch.profdata +; RUN: opt < %s -pgo-instr-use -pgo-test-profile-file=%T/switch.profdata -S | FileCheck %s --check-prefix=USE +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +; GEN: @__llvm_profile_name_test_switch = private constant [11 x i8] c"test_switch" + +define void @test_switch(i32 %i) { +entry: +; GEN: entry: +; GEN-NOT: call void @llvm.instrprof.increment + switch i32 %i, label %sw.default [ + i32 1, label %sw.bb + i32 2, label %sw.bb1 + i32 3, label %sw.bb2 + ] +; USE: ] +; USE-SAME: !prof ![[BW_SWITCH:[0-9]+]] +; USE: ![[BW_SWITCH]] = !{!"branch_weights", i32 3, i32 2, i32 0, i32 5} + +sw.bb: +; GEN: sw.bb: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([11 x i8], [11 x i8]* @__llvm_profile_name_test_switch, i32 0, i32 0), i64 46200943743, i32 4, i32 2) + br label %sw.epilog + +sw.bb1: +; GEN: sw.bb1: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([11 x i8], [11 x i8]* @__llvm_profile_name_test_switch, i32 0, i32 0), i64 46200943743, i32 4, i32 0) + br label %sw.epilog + +sw.bb2: +; GEN: sw.bb2: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([11 x i8], [11 x i8]* @__llvm_profile_name_test_switch, i32 0, i32 0), i64 46200943743, i32 4, i32 1) + br label %sw.epilog + +sw.default: +; GEN: sw.default: +; GEN: call void @llvm.instrprof.increment(i8* getelementptr inbounds ([11 x i8], [11 x i8]* @__llvm_profile_name_test_switch, i32 0, i32 0), i64 46200943743, i32 4, i32 3) + br label %sw.epilog + +sw.epilog: +; GEN: sw.epilog: +; GEN-NOT: call void @llvm.instrprof.increment + ret void +; GEN: ret void +}