| //===-- ProfileGenerator.cpp - Profile Generator ---------------*- C++ -*-===// |
| // |
| // 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 "ProfileGenerator.h" |
| #include "ErrorHandling.h" |
| #include "ProfiledBinary.h" |
| #include "llvm/ProfileData/ProfileCommon.h" |
| #include <float.h> |
| #include <unordered_set> |
| |
| cl::opt<std::string> OutputFilename("output", cl::value_desc("output"), |
| cl::Required, |
| cl::desc("Output profile file")); |
| static cl::alias OutputA("o", cl::desc("Alias for --output"), |
| cl::aliasopt(OutputFilename)); |
| |
| static cl::opt<SampleProfileFormat> OutputFormat( |
| "format", cl::desc("Format of output profile"), cl::init(SPF_Ext_Binary), |
| cl::values( |
| clEnumValN(SPF_Binary, "binary", "Binary encoding (default)"), |
| clEnumValN(SPF_Compact_Binary, "compbinary", "Compact binary encoding"), |
| clEnumValN(SPF_Ext_Binary, "extbinary", "Extensible binary encoding"), |
| clEnumValN(SPF_Text, "text", "Text encoding"), |
| clEnumValN(SPF_GCC, "gcc", |
| "GCC encoding (only meaningful for -sample)"))); |
| |
| cl::opt<bool> UseMD5( |
| "use-md5", cl::init(false), cl::Hidden, |
| cl::desc("Use md5 to represent function names in the output profile (only " |
| "meaningful for -extbinary)")); |
| |
| static cl::opt<bool> PopulateProfileSymbolList( |
| "populate-profile-symbol-list", cl::init(false), cl::Hidden, |
| cl::desc("Populate profile symbol list (only meaningful for -extbinary)")); |
| |
| static cl::opt<bool> FillZeroForAllFuncs( |
| "fill-zero-for-all-funcs", cl::init(false), cl::Hidden, |
| cl::desc("Attribute all functions' range with zero count " |
| "even it's not hit by any samples.")); |
| |
| static cl::opt<int32_t, true> RecursionCompression( |
| "compress-recursion", |
| cl::desc("Compressing recursion by deduplicating adjacent frame " |
| "sequences up to the specified size. -1 means no size limit."), |
| cl::Hidden, |
| cl::location(llvm::sampleprof::CSProfileGenerator::MaxCompressionSize)); |
| |
| static cl::opt<bool> CSProfMergeColdContext( |
| "csprof-merge-cold-context", cl::init(true), cl::ZeroOrMore, |
| cl::desc("If the total count of context profile is smaller than " |
| "the threshold, it will be merged into context-less base " |
| "profile.")); |
| |
| static cl::opt<bool> CSProfTrimColdContext( |
| "csprof-trim-cold-context", cl::init(false), cl::ZeroOrMore, |
| cl::desc("If the total count of the profile after all merge is done " |
| "is still smaller than threshold, it will be trimmed.")); |
| |
| static cl::opt<uint32_t> CSProfMaxColdContextDepth( |
| "csprof-max-cold-context-depth", cl::init(1), cl::ZeroOrMore, |
| cl::desc("Keep the last K contexts while merging cold profile. 1 means the " |
| "context-less base profile")); |
| |
| static cl::opt<int, true> CSProfMaxContextDepth( |
| "csprof-max-context-depth", cl::ZeroOrMore, |
| cl::desc("Keep the last K contexts while merging profile. -1 means no " |
| "depth limit."), |
| cl::location(llvm::sampleprof::CSProfileGenerator::MaxContextDepth)); |
| |
| static cl::opt<double> HotFunctionDensityThreshold( |
| "hot-function-density-threshold", llvm::cl::init(1000), |
| llvm::cl::desc( |
| "specify density threshold for hot functions (default: 1000)"), |
| llvm::cl::Optional); |
| static cl::opt<bool> ShowDensity("show-density", llvm::cl::init(false), |
| llvm::cl::desc("show profile density details"), |
| llvm::cl::Optional); |
| |
| extern cl::opt<int> ProfileSummaryCutoffHot; |
| |
| using namespace llvm; |
| using namespace sampleprof; |
| |
| namespace llvm { |
| namespace sampleprof { |
| |
| // Initialize the MaxCompressionSize to -1 which means no size limit |
| int32_t CSProfileGenerator::MaxCompressionSize = -1; |
| |
| int CSProfileGenerator::MaxContextDepth = -1; |
| |
| bool ProfileGeneratorBase::UseFSDiscriminator = false; |
| |
| std::unique_ptr<ProfileGeneratorBase> |
| ProfileGeneratorBase::create(ProfiledBinary *Binary, |
| const ContextSampleCounterMap &SampleCounters, |
| bool ProfileIsCS) { |
| std::unique_ptr<ProfileGeneratorBase> Generator; |
| if (ProfileIsCS) { |
| if (Binary->useFSDiscriminator()) |
| exitWithError("FS discriminator is not supported in CS profile."); |
| Generator.reset(new CSProfileGenerator(Binary, SampleCounters)); |
| } else { |
| Generator.reset(new ProfileGenerator(Binary, SampleCounters)); |
| } |
| ProfileGeneratorBase::UseFSDiscriminator = Binary->useFSDiscriminator(); |
| FunctionSamples::ProfileIsFS = Binary->useFSDiscriminator(); |
| |
| return Generator; |
| } |
| |
| void ProfileGeneratorBase::write(std::unique_ptr<SampleProfileWriter> Writer, |
| SampleProfileMap &ProfileMap) { |
| // Populate profile symbol list if extended binary format is used. |
| ProfileSymbolList SymbolList; |
| |
| if (PopulateProfileSymbolList && OutputFormat == SPF_Ext_Binary) { |
| Binary->populateSymbolListFromDWARF(SymbolList); |
| Writer->setProfileSymbolList(&SymbolList); |
| } |
| |
| if (std::error_code EC = Writer->write(ProfileMap)) |
| exitWithError(std::move(EC)); |
| } |
| |
| void ProfileGeneratorBase::write() { |
| auto WriterOrErr = SampleProfileWriter::create(OutputFilename, OutputFormat); |
| if (std::error_code EC = WriterOrErr.getError()) |
| exitWithError(EC, OutputFilename); |
| |
| if (UseMD5) { |
| if (OutputFormat != SPF_Ext_Binary) |
| WithColor::warning() << "-use-md5 is ignored. Specify " |
| "--format=extbinary to enable it\n"; |
| else |
| WriterOrErr.get()->setUseMD5(); |
| } |
| |
| write(std::move(WriterOrErr.get()), ProfileMap); |
| } |
| |
| void ProfileGeneratorBase::showDensitySuggestion(double Density) { |
| if (Density == 0.0) |
| WithColor::warning() << "The --profile-summary-cutoff-hot option may be " |
| "set too low. Please check your command.\n"; |
| else if (Density < HotFunctionDensityThreshold) |
| WithColor::warning() |
| << "AutoFDO is estimated to optimize better with " |
| << format("%.1f", HotFunctionDensityThreshold / Density) |
| << "x more samples. Please consider increasing sampling rate or " |
| "profiling for longer duration to get more samples.\n"; |
| |
| if (ShowDensity) |
| outs() << "Minimum profile density for hot functions with top " |
| << format("%.2f", |
| static_cast<double>(ProfileSummaryCutoffHot.getValue()) / |
| 10000) |
| << "% total samples: " << format("%.1f", Density) << "\n"; |
| } |
| |
| double ProfileGeneratorBase::calculateDensity(const SampleProfileMap &Profiles, |
| uint64_t HotCntThreshold) { |
| double Density = DBL_MAX; |
| std::vector<const FunctionSamples *> HotFuncs; |
| for (auto &I : Profiles) { |
| auto &FuncSamples = I.second; |
| if (FuncSamples.getTotalSamples() < HotCntThreshold) |
| continue; |
| HotFuncs.emplace_back(&FuncSamples); |
| } |
| |
| for (auto *FuncSamples : HotFuncs) { |
| auto *Func = Binary->getBinaryFunction(FuncSamples->getName()); |
| if (!Func) |
| continue; |
| uint64_t FuncSize = Func->getFuncSize(); |
| if (FuncSize == 0) |
| continue; |
| Density = |
| std::min(Density, static_cast<double>(FuncSamples->getTotalSamples()) / |
| FuncSize); |
| } |
| |
| return Density == DBL_MAX ? 0.0 : Density; |
| } |
| |
| void ProfileGeneratorBase::findDisjointRanges(RangeSample &DisjointRanges, |
| const RangeSample &Ranges) { |
| |
| /* |
| Regions may overlap with each other. Using the boundary info, find all |
| disjoint ranges and their sample count. BoundaryPoint contains the count |
| multiple samples begin/end at this points. |
| |
| |<--100-->| Sample1 |
| |<------200------>| Sample2 |
| A B C |
| |
| In the example above, |
| Sample1 begins at A, ends at B, its value is 100. |
| Sample2 beings at A, ends at C, its value is 200. |
| For A, BeginCount is the sum of sample begins at A, which is 300 and no |
| samples ends at A, so EndCount is 0. |
| Then boundary points A, B, and C with begin/end counts are: |
| A: (300, 0) |
| B: (0, 100) |
| C: (0, 200) |
| */ |
| struct BoundaryPoint { |
| // Sum of sample counts beginning at this point |
| uint64_t BeginCount = UINT64_MAX; |
| // Sum of sample counts ending at this point |
| uint64_t EndCount = UINT64_MAX; |
| // Is the begin point of a zero range. |
| bool IsZeroRangeBegin = false; |
| // Is the end point of a zero range. |
| bool IsZeroRangeEnd = false; |
| |
| void addBeginCount(uint64_t Count) { |
| if (BeginCount == UINT64_MAX) |
| BeginCount = 0; |
| BeginCount += Count; |
| } |
| |
| void addEndCount(uint64_t Count) { |
| if (EndCount == UINT64_MAX) |
| EndCount = 0; |
| EndCount += Count; |
| } |
| }; |
| |
| /* |
| For the above example. With boundary points, follwing logic finds two |
| disjoint region of |
| |
| [A,B]: 300 |
| [B+1,C]: 200 |
| |
| If there is a boundary point that both begin and end, the point itself |
| becomes a separate disjoint region. For example, if we have original |
| ranges of |
| |
| |<--- 100 --->| |
| |<--- 200 --->| |
| A B C |
| |
| there are three boundary points with their begin/end counts of |
| |
| A: (100, 0) |
| B: (200, 100) |
| C: (0, 200) |
| |
| the disjoint ranges would be |
| |
| [A, B-1]: 100 |
| [B, B]: 300 |
| [B+1, C]: 200. |
| |
| Example for zero value range: |
| |
| |<--- 100 --->| |
| |<--- 200 --->| |
| |<--------------- 0 ----------------->| |
| A B C D E F |
| |
| [A, B-1] : 0 |
| [B, C] : 100 |
| [C+1, D-1]: 0 |
| [D, E] : 200 |
| [E+1, F] : 0 |
| */ |
| std::map<uint64_t, BoundaryPoint> Boundaries; |
| |
| for (auto Item : Ranges) { |
| assert(Item.first.first <= Item.first.second && |
| "Invalid instruction range"); |
| auto &BeginPoint = Boundaries[Item.first.first]; |
| auto &EndPoint = Boundaries[Item.first.second]; |
| uint64_t Count = Item.second; |
| |
| BeginPoint.addBeginCount(Count); |
| EndPoint.addEndCount(Count); |
| if (Count == 0) { |
| BeginPoint.IsZeroRangeBegin = true; |
| EndPoint.IsZeroRangeEnd = true; |
| } |
| } |
| |
| // Use UINT64_MAX to indicate there is no existing range between BeginAddress |
| // and the next valid address |
| uint64_t BeginAddress = UINT64_MAX; |
| int ZeroRangeDepth = 0; |
| uint64_t Count = 0; |
| for (auto Item : Boundaries) { |
| uint64_t Address = Item.first; |
| BoundaryPoint &Point = Item.second; |
| if (Point.BeginCount != UINT64_MAX) { |
| if (BeginAddress != UINT64_MAX) |
| DisjointRanges[{BeginAddress, Address - 1}] = Count; |
| Count += Point.BeginCount; |
| BeginAddress = Address; |
| ZeroRangeDepth += Point.IsZeroRangeBegin; |
| } |
| if (Point.EndCount != UINT64_MAX) { |
| assert((BeginAddress != UINT64_MAX) && |
| "First boundary point cannot be 'end' point"); |
| DisjointRanges[{BeginAddress, Address}] = Count; |
| assert(Count >= Point.EndCount && "Mismatched live ranges"); |
| Count -= Point.EndCount; |
| BeginAddress = Address + 1; |
| ZeroRangeDepth -= Point.IsZeroRangeEnd; |
| // If the remaining count is zero and it's no longer in a zero range, this |
| // means we consume all the ranges before, thus mark BeginAddress as |
| // UINT64_MAX. e.g. supposing we have two non-overlapping ranges: |
| // [<---- 10 ---->] |
| // [<---- 20 ---->] |
| // A B C D |
| // The BeginAddress(B+1) will reset to invalid(UINT64_MAX), so we won't |
| // have the [B+1, C-1] zero range. |
| if (Count == 0 && ZeroRangeDepth == 0) |
| BeginAddress = UINT64_MAX; |
| } |
| } |
| } |
| |
| void ProfileGeneratorBase::updateBodySamplesforFunctionProfile( |
| FunctionSamples &FunctionProfile, const SampleContextFrame &LeafLoc, |
| uint64_t Count) { |
| // Use the maximum count of samples with same line location |
| uint32_t Discriminator = getBaseDiscriminator(LeafLoc.Location.Discriminator); |
| |
| // Use duplication factor to compensated for loop unroll/vectorization. |
| // Note that this is only needed when we're taking MAX of the counts at |
| // the location instead of SUM. |
| Count *= getDuplicationFactor(LeafLoc.Location.Discriminator); |
| |
| ErrorOr<uint64_t> R = |
| FunctionProfile.findSamplesAt(LeafLoc.Location.LineOffset, Discriminator); |
| |
| uint64_t PreviousCount = R ? R.get() : 0; |
| if (PreviousCount <= Count) { |
| FunctionProfile.addBodySamples(LeafLoc.Location.LineOffset, Discriminator, |
| Count - PreviousCount); |
| } |
| } |
| |
| void ProfileGeneratorBase::updateTotalSamples() { |
| for (auto &Item : ProfileMap) { |
| FunctionSamples &FunctionProfile = Item.second; |
| FunctionProfile.updateTotalSamples(); |
| } |
| } |
| |
| FunctionSamples & |
| ProfileGenerator::getTopLevelFunctionProfile(StringRef FuncName) { |
| SampleContext Context(FuncName); |
| auto Ret = ProfileMap.emplace(Context, FunctionSamples()); |
| if (Ret.second) { |
| FunctionSamples &FProfile = Ret.first->second; |
| FProfile.setContext(Context); |
| } |
| return Ret.first->second; |
| } |
| |
| void ProfileGenerator::generateProfile() { |
| if (Binary->usePseudoProbes()) { |
| // TODO: Support probe based profile generation |
| } else { |
| generateLineNumBasedProfile(); |
| } |
| postProcessProfiles(); |
| } |
| |
| void ProfileGenerator::postProcessProfiles() { |
| computeSummaryAndThreshold(); |
| calculateAndShowDensity(ProfileMap); |
| } |
| |
| void ProfileGenerator::generateLineNumBasedProfile() { |
| assert(SampleCounters.size() == 1 && |
| "Must have one entry for profile generation."); |
| const SampleCounter &SC = SampleCounters.begin()->second; |
| // Fill in function body samples |
| populateBodySamplesForAllFunctions(SC.RangeCounter); |
| // Fill in boundary sample counts as well as call site samples for calls |
| populateBoundarySamplesForAllFunctions(SC.BranchCounter); |
| |
| updateTotalSamples(); |
| } |
| |
| FunctionSamples &ProfileGenerator::getLeafFrameProfile( |
| const SampleContextFrameVector &FrameVec) { |
| // Get top level profile |
| FunctionSamples *FunctionProfile = |
| &getTopLevelFunctionProfile(FrameVec[0].FuncName); |
| |
| for (size_t I = 1; I < FrameVec.size(); I++) { |
| LineLocation Callsite( |
| FrameVec[I - 1].Location.LineOffset, |
| getBaseDiscriminator(FrameVec[I - 1].Location.Discriminator)); |
| FunctionSamplesMap &SamplesMap = |
| FunctionProfile->functionSamplesAt(Callsite); |
| auto Ret = |
| SamplesMap.emplace(FrameVec[I].FuncName.str(), FunctionSamples()); |
| if (Ret.second) { |
| SampleContext Context(FrameVec[I].FuncName); |
| Ret.first->second.setContext(Context); |
| } |
| FunctionProfile = &Ret.first->second; |
| } |
| |
| return *FunctionProfile; |
| } |
| |
| RangeSample |
| ProfileGenerator::preprocessRangeCounter(const RangeSample &RangeCounter) { |
| RangeSample Ranges(RangeCounter.begin(), RangeCounter.end()); |
| if (FillZeroForAllFuncs) { |
| for (auto &FuncI : Binary->getAllBinaryFunctions()) { |
| for (auto &R : FuncI.second.Ranges) { |
| Ranges[{R.first, R.second - 1}] += 0; |
| } |
| } |
| } else { |
| // For each range, we search for all ranges of the function it belongs to |
| // and initialize it with zero count, so it remains zero if doesn't hit any |
| // samples. This is to be consistent with compiler that interpret zero count |
| // as unexecuted(cold). |
| for (auto I : RangeCounter) { |
| uint64_t StartOffset = I.first.first; |
| for (const auto &Range : Binary->getRangesForOffset(StartOffset)) |
| Ranges[{Range.first, Range.second - 1}] += 0; |
| } |
| } |
| RangeSample DisjointRanges; |
| findDisjointRanges(DisjointRanges, Ranges); |
| return DisjointRanges; |
| } |
| |
| void ProfileGenerator::populateBodySamplesForAllFunctions( |
| const RangeSample &RangeCounter) { |
| for (auto Range : preprocessRangeCounter(RangeCounter)) { |
| uint64_t RangeBegin = Binary->offsetToVirtualAddr(Range.first.first); |
| uint64_t RangeEnd = Binary->offsetToVirtualAddr(Range.first.second); |
| uint64_t Count = Range.second; |
| |
| InstructionPointer IP(Binary, RangeBegin, true); |
| // Disjoint ranges may have range in the middle of two instr, |
| // e.g. If Instr1 at Addr1, and Instr2 at Addr2, disjoint range |
| // can be Addr1+1 to Addr2-1. We should ignore such range. |
| if (IP.Address > RangeEnd) |
| continue; |
| |
| do { |
| uint64_t Offset = Binary->virtualAddrToOffset(IP.Address); |
| const SampleContextFrameVector &FrameVec = |
| Binary->getFrameLocationStack(Offset); |
| if (!FrameVec.empty()) { |
| FunctionSamples &FunctionProfile = getLeafFrameProfile(FrameVec); |
| updateBodySamplesforFunctionProfile(FunctionProfile, FrameVec.back(), |
| Count); |
| } |
| } while (IP.advance() && IP.Address <= RangeEnd); |
| } |
| } |
| |
| StringRef ProfileGeneratorBase::getCalleeNameForOffset(uint64_t TargetOffset) { |
| // Get the function range by branch target if it's a call branch. |
| auto *FRange = Binary->findFuncRangeForStartOffset(TargetOffset); |
| |
| // We won't accumulate sample count for a range whose start is not the real |
| // function entry such as outlined function or inner labels. |
| if (!FRange || !FRange->IsFuncEntry) |
| return StringRef(); |
| |
| return FunctionSamples::getCanonicalFnName(FRange->getFuncName()); |
| } |
| |
| void ProfileGenerator::populateBoundarySamplesForAllFunctions( |
| const BranchSample &BranchCounters) { |
| for (auto Entry : BranchCounters) { |
| uint64_t SourceOffset = Entry.first.first; |
| uint64_t TargetOffset = Entry.first.second; |
| uint64_t Count = Entry.second; |
| assert(Count != 0 && "Unexpected zero weight branch"); |
| |
| StringRef CalleeName = getCalleeNameForOffset(TargetOffset); |
| if (CalleeName.size() == 0) |
| continue; |
| // Record called target sample and its count. |
| const SampleContextFrameVector &FrameVec = |
| Binary->getFrameLocationStack(SourceOffset); |
| if (!FrameVec.empty()) { |
| FunctionSamples &FunctionProfile = getLeafFrameProfile(FrameVec); |
| FunctionProfile.addCalledTargetSamples( |
| FrameVec.back().Location.LineOffset, |
| getBaseDiscriminator(FrameVec.back().Location.Discriminator), |
| CalleeName, Count); |
| } |
| // Add head samples for callee. |
| FunctionSamples &CalleeProfile = getTopLevelFunctionProfile(CalleeName); |
| CalleeProfile.addHeadSamples(Count); |
| } |
| } |
| |
| void ProfileGeneratorBase::calculateAndShowDensity( |
| const SampleProfileMap &Profiles) { |
| double Density = calculateDensity(Profiles, HotCountThreshold); |
| showDensitySuggestion(Density); |
| } |
| |
| FunctionSamples &CSProfileGenerator::getFunctionProfileForContext( |
| const SampleContextFrameVector &Context, bool WasLeafInlined) { |
| auto I = ProfileMap.find(SampleContext(Context)); |
| if (I == ProfileMap.end()) { |
| // Save the new context for future references. |
| SampleContextFrames NewContext = *Contexts.insert(Context).first; |
| SampleContext FContext(NewContext, RawContext); |
| auto Ret = ProfileMap.emplace(FContext, FunctionSamples()); |
| if (WasLeafInlined) |
| FContext.setAttribute(ContextWasInlined); |
| FunctionSamples &FProfile = Ret.first->second; |
| FProfile.setContext(FContext); |
| return Ret.first->second; |
| } |
| return I->second; |
| } |
| |
| void CSProfileGenerator::generateProfile() { |
| FunctionSamples::ProfileIsCS = true; |
| |
| if (Binary->getTrackFuncContextSize()) |
| computeSizeForProfiledFunctions(); |
| |
| if (Binary->usePseudoProbes()) { |
| // Enable pseudo probe functionalities in SampleProf |
| FunctionSamples::ProfileIsProbeBased = true; |
| generateProbeBasedProfile(); |
| } else { |
| generateLineNumBasedProfile(); |
| } |
| postProcessProfiles(); |
| } |
| |
| void CSProfileGenerator::computeSizeForProfiledFunctions() { |
| // Hash map to deduplicate the function range and the item is a pair of |
| // function start and end offset. |
| std::unordered_map<uint64_t, uint64_t> AggregatedRanges; |
| // Go through all the ranges in the CS counters, use the start of the range to |
| // look up the function it belongs and record the function range. |
| for (const auto &CI : SampleCounters) { |
| for (auto Item : CI.second.RangeCounter) { |
| // FIXME: Filter the bogus crossing function range. |
| uint64_t StartOffset = Item.first.first; |
| // Note that a function can be spilt into multiple ranges, so get all |
| // ranges of the function. |
| for (const auto &Range : Binary->getRangesForOffset(StartOffset)) |
| AggregatedRanges[Range.first] = Range.second; |
| } |
| } |
| |
| for (auto I : AggregatedRanges) { |
| uint64_t StartOffset = I.first; |
| uint64_t EndOffset = I.second; |
| Binary->computeInlinedContextSizeForRange(StartOffset, EndOffset); |
| } |
| } |
| |
| void CSProfileGenerator::generateLineNumBasedProfile() { |
| for (const auto &CI : SampleCounters) { |
| const StringBasedCtxKey *CtxKey = |
| dyn_cast<StringBasedCtxKey>(CI.first.getPtr()); |
| // Get or create function profile for the range |
| FunctionSamples &FunctionProfile = |
| getFunctionProfileForContext(CtxKey->Context, CtxKey->WasLeafInlined); |
| |
| // Fill in function body samples |
| populateBodySamplesForFunction(FunctionProfile, CI.second.RangeCounter); |
| // Fill in boundary sample counts as well as call site samples for calls |
| populateBoundarySamplesForFunction(CtxKey->Context, FunctionProfile, |
| CI.second.BranchCounter); |
| } |
| // Fill in call site value sample for inlined calls and also use context to |
| // infer missing samples. Since we don't have call count for inlined |
| // functions, we estimate it from inlinee's profile using the entry of the |
| // body sample. |
| populateInferredFunctionSamples(); |
| |
| updateTotalSamples(); |
| } |
| |
| void CSProfileGenerator::populateBodySamplesForFunction( |
| FunctionSamples &FunctionProfile, const RangeSample &RangeCounter) { |
| // Compute disjoint ranges first, so we can use MAX |
| // for calculating count for each location. |
| RangeSample Ranges; |
| findDisjointRanges(Ranges, RangeCounter); |
| for (auto Range : Ranges) { |
| uint64_t RangeBegin = Binary->offsetToVirtualAddr(Range.first.first); |
| uint64_t RangeEnd = Binary->offsetToVirtualAddr(Range.first.second); |
| uint64_t Count = Range.second; |
| // Disjoint ranges have introduce zero-filled gap that |
| // doesn't belong to current context, filter them out. |
| if (Count == 0) |
| continue; |
| |
| InstructionPointer IP(Binary, RangeBegin, true); |
| // Disjoint ranges may have range in the middle of two instr, |
| // e.g. If Instr1 at Addr1, and Instr2 at Addr2, disjoint range |
| // can be Addr1+1 to Addr2-1. We should ignore such range. |
| if (IP.Address > RangeEnd) |
| continue; |
| |
| do { |
| uint64_t Offset = Binary->virtualAddrToOffset(IP.Address); |
| auto LeafLoc = Binary->getInlineLeafFrameLoc(Offset); |
| if (LeafLoc.hasValue()) { |
| // Recording body sample for this specific context |
| updateBodySamplesforFunctionProfile(FunctionProfile, *LeafLoc, Count); |
| } |
| } while (IP.advance() && IP.Address <= RangeEnd); |
| } |
| } |
| |
| void CSProfileGenerator::populateBoundarySamplesForFunction( |
| SampleContextFrames ContextId, FunctionSamples &FunctionProfile, |
| const BranchSample &BranchCounters) { |
| |
| for (auto Entry : BranchCounters) { |
| uint64_t SourceOffset = Entry.first.first; |
| uint64_t TargetOffset = Entry.first.second; |
| uint64_t Count = Entry.second; |
| assert(Count != 0 && "Unexpected zero weight branch"); |
| |
| StringRef CalleeName = getCalleeNameForOffset(TargetOffset); |
| if (CalleeName.size() == 0) |
| continue; |
| |
| // Record called target sample and its count |
| auto LeafLoc = Binary->getInlineLeafFrameLoc(SourceOffset); |
| if (!LeafLoc.hasValue()) |
| continue; |
| FunctionProfile.addCalledTargetSamples( |
| LeafLoc->Location.LineOffset, |
| getBaseDiscriminator(LeafLoc->Location.Discriminator), CalleeName, |
| Count); |
| |
| // Record head sample for called target(callee) |
| SampleContextFrameVector CalleeCtx(ContextId.begin(), ContextId.end()); |
| assert(CalleeCtx.back().FuncName == LeafLoc->FuncName && |
| "Leaf function name doesn't match"); |
| CalleeCtx.back() = *LeafLoc; |
| CalleeCtx.emplace_back(CalleeName, LineLocation(0, 0)); |
| FunctionSamples &CalleeProfile = getFunctionProfileForContext(CalleeCtx); |
| CalleeProfile.addHeadSamples(Count); |
| } |
| } |
| |
| static SampleContextFrame |
| getCallerContext(SampleContextFrames CalleeContext, |
| SampleContextFrameVector &CallerContext) { |
| assert(CalleeContext.size() > 1 && "Unexpected empty context"); |
| CalleeContext = CalleeContext.drop_back(); |
| CallerContext.assign(CalleeContext.begin(), CalleeContext.end()); |
| SampleContextFrame CallerFrame = CallerContext.back(); |
| CallerContext.back().Location = LineLocation(0, 0); |
| return CallerFrame; |
| } |
| |
| void CSProfileGenerator::populateInferredFunctionSamples() { |
| for (const auto &Item : ProfileMap) { |
| const auto &CalleeContext = Item.first; |
| const FunctionSamples &CalleeProfile = Item.second; |
| |
| // If we already have head sample counts, we must have value profile |
| // for call sites added already. Skip to avoid double counting. |
| if (CalleeProfile.getHeadSamples()) |
| continue; |
| // If we don't have context, nothing to do for caller's call site. |
| // This could happen for entry point function. |
| if (CalleeContext.isBaseContext()) |
| continue; |
| |
| // Infer Caller's frame loc and context ID through string splitting |
| SampleContextFrameVector CallerContextId; |
| SampleContextFrame &&CallerLeafFrameLoc = |
| getCallerContext(CalleeContext.getContextFrames(), CallerContextId); |
| SampleContextFrames CallerContext(CallerContextId); |
| |
| // It's possible that we haven't seen any sample directly in the caller, |
| // in which case CallerProfile will not exist. But we can't modify |
| // ProfileMap while iterating it. |
| // TODO: created function profile for those callers too |
| if (ProfileMap.find(CallerContext) == ProfileMap.end()) |
| continue; |
| FunctionSamples &CallerProfile = ProfileMap[CallerContext]; |
| |
| // Since we don't have call count for inlined functions, we |
| // estimate it from inlinee's profile using entry body sample. |
| uint64_t EstimatedCallCount = CalleeProfile.getEntrySamples(); |
| // If we don't have samples with location, use 1 to indicate live. |
| if (!EstimatedCallCount && !CalleeProfile.getBodySamples().size()) |
| EstimatedCallCount = 1; |
| CallerProfile.addCalledTargetSamples( |
| CallerLeafFrameLoc.Location.LineOffset, |
| CallerLeafFrameLoc.Location.Discriminator, |
| CalleeProfile.getContext().getName(), EstimatedCallCount); |
| CallerProfile.addBodySamples(CallerLeafFrameLoc.Location.LineOffset, |
| CallerLeafFrameLoc.Location.Discriminator, |
| EstimatedCallCount); |
| } |
| } |
| |
| void CSProfileGenerator::postProcessProfiles() { |
| // Compute hot/cold threshold based on profile. This will be used for cold |
| // context profile merging/trimming. |
| computeSummaryAndThreshold(); |
| |
| // Run global pre-inliner to adjust/merge context profile based on estimated |
| // inline decisions. |
| if (EnableCSPreInliner) { |
| CSPreInliner(ProfileMap, *Binary, HotCountThreshold, ColdCountThreshold) |
| .run(); |
| // Turn off the profile merger by default unless it is explicitly enabled. |
| if (!CSProfMergeColdContext.getNumOccurrences()) |
| CSProfMergeColdContext = false; |
| } |
| |
| // Trim and merge cold context profile using cold threshold above. |
| if (CSProfTrimColdContext || CSProfMergeColdContext) { |
| SampleContextTrimmer(ProfileMap) |
| .trimAndMergeColdContextProfiles( |
| HotCountThreshold, CSProfTrimColdContext, CSProfMergeColdContext, |
| CSProfMaxColdContextDepth, EnableCSPreInliner); |
| } |
| |
| // Merge function samples of CS profile to calculate profile density. |
| sampleprof::SampleProfileMap ContextLessProfiles; |
| for (const auto &I : ProfileMap) { |
| ContextLessProfiles[I.second.getName()].merge(I.second); |
| } |
| |
| calculateAndShowDensity(ContextLessProfiles); |
| } |
| |
| void ProfileGeneratorBase::computeSummaryAndThreshold() { |
| SampleProfileSummaryBuilder Builder(ProfileSummaryBuilder::DefaultCutoffs); |
| auto Summary = Builder.computeSummaryForProfiles(ProfileMap); |
| HotCountThreshold = ProfileSummaryBuilder::getHotCountThreshold( |
| (Summary->getDetailedSummary())); |
| ColdCountThreshold = ProfileSummaryBuilder::getColdCountThreshold( |
| (Summary->getDetailedSummary())); |
| } |
| |
| // Helper function to extract context prefix string stack |
| // Extract context stack for reusing, leaf context stack will |
| // be added compressed while looking up function profile |
| static void extractPrefixContextStack( |
| SampleContextFrameVector &ContextStack, |
| const SmallVectorImpl<const MCDecodedPseudoProbe *> &Probes, |
| ProfiledBinary *Binary) { |
| for (const auto *P : Probes) { |
| Binary->getInlineContextForProbe(P, ContextStack, true); |
| } |
| } |
| |
| void CSProfileGenerator::generateProbeBasedProfile() { |
| for (const auto &CI : SampleCounters) { |
| const ProbeBasedCtxKey *CtxKey = |
| dyn_cast<ProbeBasedCtxKey>(CI.first.getPtr()); |
| SampleContextFrameVector ContextStack; |
| extractPrefixContextStack(ContextStack, CtxKey->Probes, Binary); |
| // Fill in function body samples from probes, also infer caller's samples |
| // from callee's probe |
| populateBodySamplesWithProbes(CI.second.RangeCounter, ContextStack); |
| // Fill in boundary samples for a call probe |
| populateBoundarySamplesWithProbes(CI.second.BranchCounter, ContextStack); |
| } |
| } |
| |
| void CSProfileGenerator::extractProbesFromRange(const RangeSample &RangeCounter, |
| ProbeCounterMap &ProbeCounter) { |
| RangeSample Ranges; |
| findDisjointRanges(Ranges, RangeCounter); |
| for (const auto &Range : Ranges) { |
| uint64_t RangeBegin = Binary->offsetToVirtualAddr(Range.first.first); |
| uint64_t RangeEnd = Binary->offsetToVirtualAddr(Range.first.second); |
| uint64_t Count = Range.second; |
| // Disjoint ranges have introduce zero-filled gap that |
| // doesn't belong to current context, filter them out. |
| if (Count == 0) |
| continue; |
| |
| InstructionPointer IP(Binary, RangeBegin, true); |
| // Disjoint ranges may have range in the middle of two instr, |
| // e.g. If Instr1 at Addr1, and Instr2 at Addr2, disjoint range |
| // can be Addr1+1 to Addr2-1. We should ignore such range. |
| if (IP.Address > RangeEnd) |
| continue; |
| |
| do { |
| const AddressProbesMap &Address2ProbesMap = |
| Binary->getAddress2ProbesMap(); |
| auto It = Address2ProbesMap.find(IP.Address); |
| if (It != Address2ProbesMap.end()) { |
| for (const auto &Probe : It->second) { |
| if (!Probe.isBlock()) |
| continue; |
| ProbeCounter[&Probe] += Count; |
| } |
| } |
| } while (IP.advance() && IP.Address <= RangeEnd); |
| } |
| } |
| |
| void CSProfileGenerator::populateBodySamplesWithProbes( |
| const RangeSample &RangeCounter, SampleContextFrames ContextStack) { |
| ProbeCounterMap ProbeCounter; |
| // Extract the top frame probes by looking up each address among the range in |
| // the Address2ProbeMap |
| extractProbesFromRange(RangeCounter, ProbeCounter); |
| std::unordered_map<MCDecodedPseudoProbeInlineTree *, |
| std::unordered_set<FunctionSamples *>> |
| FrameSamples; |
| for (auto PI : ProbeCounter) { |
| const MCDecodedPseudoProbe *Probe = PI.first; |
| uint64_t Count = PI.second; |
| FunctionSamples &FunctionProfile = |
| getFunctionProfileForLeafProbe(ContextStack, Probe); |
| // Record the current frame and FunctionProfile whenever samples are |
| // collected for non-danglie probes. This is for reporting all of the |
| // zero count probes of the frame later. |
| FrameSamples[Probe->getInlineTreeNode()].insert(&FunctionProfile); |
| FunctionProfile.addBodySamplesForProbe(Probe->getIndex(), Count); |
| FunctionProfile.addTotalSamples(Count); |
| if (Probe->isEntry()) { |
| FunctionProfile.addHeadSamples(Count); |
| // Look up for the caller's function profile |
| const auto *InlinerDesc = Binary->getInlinerDescForProbe(Probe); |
| SampleContextFrames CalleeContextId = |
| FunctionProfile.getContext().getContextFrames(); |
| if (InlinerDesc != nullptr && CalleeContextId.size() > 1) { |
| // Since the context id will be compressed, we have to use callee's |
| // context id to infer caller's context id to ensure they share the |
| // same context prefix. |
| SampleContextFrameVector CallerContextId; |
| SampleContextFrame &&CallerLeafFrameLoc = |
| getCallerContext(CalleeContextId, CallerContextId); |
| uint64_t CallerIndex = CallerLeafFrameLoc.Location.LineOffset; |
| assert(CallerIndex && |
| "Inferred caller's location index shouldn't be zero!"); |
| FunctionSamples &CallerProfile = |
| getFunctionProfileForContext(CallerContextId); |
| CallerProfile.setFunctionHash(InlinerDesc->FuncHash); |
| CallerProfile.addBodySamples(CallerIndex, 0, Count); |
| CallerProfile.addTotalSamples(Count); |
| CallerProfile.addCalledTargetSamples( |
| CallerIndex, 0, FunctionProfile.getContext().getName(), Count); |
| } |
| } |
| } |
| |
| // Assign zero count for remaining probes without sample hits to |
| // differentiate from probes optimized away, of which the counts are unknown |
| // and will be inferred by the compiler. |
| for (auto &I : FrameSamples) { |
| for (auto *FunctionProfile : I.second) { |
| for (auto *Probe : I.first->getProbes()) { |
| FunctionProfile->addBodySamplesForProbe(Probe->getIndex(), 0); |
| } |
| } |
| } |
| } |
| |
| void CSProfileGenerator::populateBoundarySamplesWithProbes( |
| const BranchSample &BranchCounter, SampleContextFrames ContextStack) { |
| for (auto BI : BranchCounter) { |
| uint64_t SourceOffset = BI.first.first; |
| uint64_t TargetOffset = BI.first.second; |
| uint64_t Count = BI.second; |
| uint64_t SourceAddress = Binary->offsetToVirtualAddr(SourceOffset); |
| const MCDecodedPseudoProbe *CallProbe = |
| Binary->getCallProbeForAddr(SourceAddress); |
| if (CallProbe == nullptr) |
| continue; |
| FunctionSamples &FunctionProfile = |
| getFunctionProfileForLeafProbe(ContextStack, CallProbe); |
| FunctionProfile.addBodySamples(CallProbe->getIndex(), 0, Count); |
| FunctionProfile.addTotalSamples(Count); |
| StringRef CalleeName = getCalleeNameForOffset(TargetOffset); |
| if (CalleeName.size() == 0) |
| continue; |
| FunctionProfile.addCalledTargetSamples(CallProbe->getIndex(), 0, CalleeName, |
| Count); |
| } |
| } |
| |
| FunctionSamples &CSProfileGenerator::getFunctionProfileForLeafProbe( |
| SampleContextFrames ContextStack, const MCDecodedPseudoProbe *LeafProbe) { |
| |
| // Explicitly copy the context for appending the leaf context |
| SampleContextFrameVector NewContextStack(ContextStack.begin(), |
| ContextStack.end()); |
| Binary->getInlineContextForProbe(LeafProbe, NewContextStack, true); |
| // For leaf inlined context with the top frame, we should strip off the top |
| // frame's probe id, like: |
| // Inlined stack: [foo:1, bar:2], the ContextId will be "foo:1 @ bar" |
| auto LeafFrame = NewContextStack.back(); |
| LeafFrame.Location = LineLocation(0, 0); |
| NewContextStack.pop_back(); |
| // Compress the context string except for the leaf frame |
| CSProfileGenerator::compressRecursionContext(NewContextStack); |
| CSProfileGenerator::trimContext(NewContextStack); |
| NewContextStack.push_back(LeafFrame); |
| |
| const auto *FuncDesc = Binary->getFuncDescForGUID(LeafProbe->getGuid()); |
| bool WasLeafInlined = LeafProbe->getInlineTreeNode()->hasInlineSite(); |
| FunctionSamples &FunctionProile = |
| getFunctionProfileForContext(NewContextStack, WasLeafInlined); |
| FunctionProile.setFunctionHash(FuncDesc->FuncHash); |
| return FunctionProile; |
| } |
| |
| } // end namespace sampleprof |
| } // end namespace llvm |
