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Diffstat (limited to 'llvm/lib/ProfileData/InstrProf.cpp')
| -rw-r--r-- | llvm/lib/ProfileData/InstrProf.cpp | 1280 |
1 files changed, 1280 insertions, 0 deletions
diff --git a/llvm/lib/ProfileData/InstrProf.cpp b/llvm/lib/ProfileData/InstrProf.cpp new file mode 100644 index 000000000000..57d4fbc59f83 --- /dev/null +++ b/llvm/lib/ProfileData/InstrProf.cpp @@ -0,0 +1,1280 @@ +//===- InstrProf.cpp - Instrumented profiling format support --------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// This file contains support for clang's instrumentation based PGO and +// coverage. +// +//===----------------------------------------------------------------------===// + +#include "llvm/ProfileData/InstrProf.h" +#include "llvm/ADT/ArrayRef.h" +#include "llvm/ADT/SmallString.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/ADT/StringExtras.h" +#include "llvm/ADT/StringRef.h" +#include "llvm/ADT/Triple.h" +#include "llvm/IR/Constant.h" +#include "llvm/IR/Constants.h" +#include "llvm/IR/Function.h" +#include "llvm/IR/GlobalValue.h" +#include "llvm/IR/GlobalVariable.h" +#include "llvm/IR/Instruction.h" +#include "llvm/IR/LLVMContext.h" +#include "llvm/IR/MDBuilder.h" +#include "llvm/IR/Metadata.h" +#include "llvm/IR/Module.h" +#include "llvm/IR/Type.h" +#include "llvm/ProfileData/InstrProfReader.h" +#include "llvm/Support/Casting.h" +#include "llvm/Support/CommandLine.h" +#include "llvm/Support/Compiler.h" +#include "llvm/Support/Compression.h" +#include "llvm/Support/Endian.h" +#include "llvm/Support/Error.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/LEB128.h" +#include "llvm/Support/ManagedStatic.h" +#include "llvm/Support/MathExtras.h" +#include "llvm/Support/Path.h" +#include "llvm/Support/SwapByteOrder.h" +#include <algorithm> +#include <cassert> +#include <cstddef> +#include <cstdint> +#include <cstring> +#include <memory> +#include <string> +#include <system_error> +#include <utility> +#include <vector> + +using namespace llvm; + +static cl::opt<bool> StaticFuncFullModulePrefix( + "static-func-full-module-prefix", cl::init(true), cl::Hidden, + cl::desc("Use full module build paths in the profile counter names for " + "static functions.")); + +// This option is tailored to users that have different top-level directory in +// profile-gen and profile-use compilation. Users need to specific the number +// of levels to strip. A value larger than the number of directories in the +// source file will strip all the directory names and only leave the basename. +// +// Note current ThinLTO module importing for the indirect-calls assumes +// the source directory name not being stripped. A non-zero option value here +// can potentially prevent some inter-module indirect-call-promotions. +static cl::opt<unsigned> StaticFuncStripDirNamePrefix( + "static-func-strip-dirname-prefix", cl::init(0), cl::Hidden, + cl::desc("Strip specified level of directory name from source path in " + "the profile counter name for static functions.")); + +static std::string getInstrProfErrString(instrprof_error Err) { + switch (Err) { + case instrprof_error::success: + return "Success"; + case instrprof_error::eof: + return "End of File"; + case instrprof_error::unrecognized_format: + return "Unrecognized instrumentation profile encoding format"; + case instrprof_error::bad_magic: + return "Invalid instrumentation profile data (bad magic)"; + case instrprof_error::bad_header: + return "Invalid instrumentation profile data (file header is corrupt)"; + case instrprof_error::unsupported_version: + return "Unsupported instrumentation profile format version"; + case instrprof_error::unsupported_hash_type: + return "Unsupported instrumentation profile hash type"; + case instrprof_error::too_large: + return "Too much profile data"; + case instrprof_error::truncated: + return "Truncated profile data"; + case instrprof_error::malformed: + return "Malformed instrumentation profile data"; + case instrprof_error::unknown_function: + return "No profile data available for function"; + case instrprof_error::hash_mismatch: + return "Function control flow change detected (hash mismatch)"; + case instrprof_error::count_mismatch: + return "Function basic block count change detected (counter mismatch)"; + case instrprof_error::counter_overflow: + return "Counter overflow"; + case instrprof_error::value_site_count_mismatch: + return "Function value site count change detected (counter mismatch)"; + case instrprof_error::compress_failed: + return "Failed to compress data (zlib)"; + case instrprof_error::uncompress_failed: + return "Failed to uncompress data (zlib)"; + case instrprof_error::empty_raw_profile: + return "Empty raw profile file"; + case instrprof_error::zlib_unavailable: + return "Profile uses zlib compression but the profile reader was built without zlib support"; + } + llvm_unreachable("A value of instrprof_error has no message."); +} + +namespace { + +// FIXME: This class is only here to support the transition to llvm::Error. It +// will be removed once this transition is complete. Clients should prefer to +// deal with the Error value directly, rather than converting to error_code. +class InstrProfErrorCategoryType : public std::error_category { + const char *name() const noexcept override { return "llvm.instrprof"; } + + std::string message(int IE) const override { + return getInstrProfErrString(static_cast<instrprof_error>(IE)); + } +}; + +} // end anonymous namespace + +static ManagedStatic<InstrProfErrorCategoryType> ErrorCategory; + +const std::error_category &llvm::instrprof_category() { + return *ErrorCategory; +} + +namespace { + +const char *InstrProfSectNameCommon[] = { +#define INSTR_PROF_SECT_ENTRY(Kind, SectNameCommon, SectNameCoff, Prefix) \ + SectNameCommon, +#include "llvm/ProfileData/InstrProfData.inc" +}; + +const char *InstrProfSectNameCoff[] = { +#define INSTR_PROF_SECT_ENTRY(Kind, SectNameCommon, SectNameCoff, Prefix) \ + SectNameCoff, +#include "llvm/ProfileData/InstrProfData.inc" +}; + +const char *InstrProfSectNamePrefix[] = { +#define INSTR_PROF_SECT_ENTRY(Kind, SectNameCommon, SectNameCoff, Prefix) \ + Prefix, +#include "llvm/ProfileData/InstrProfData.inc" +}; + +} // namespace + +namespace llvm { + +std::string getInstrProfSectionName(InstrProfSectKind IPSK, + Triple::ObjectFormatType OF, + bool AddSegmentInfo) { + std::string SectName; + + if (OF == Triple::MachO && AddSegmentInfo) + SectName = InstrProfSectNamePrefix[IPSK]; + + if (OF == Triple::COFF) + SectName += InstrProfSectNameCoff[IPSK]; + else + SectName += InstrProfSectNameCommon[IPSK]; + + if (OF == Triple::MachO && IPSK == IPSK_data && AddSegmentInfo) + SectName += ",regular,live_support"; + + return SectName; +} + +void SoftInstrProfErrors::addError(instrprof_error IE) { + if (IE == instrprof_error::success) + return; + + if (FirstError == instrprof_error::success) + FirstError = IE; + + switch (IE) { + case instrprof_error::hash_mismatch: + ++NumHashMismatches; + break; + case instrprof_error::count_mismatch: + ++NumCountMismatches; + break; + case instrprof_error::counter_overflow: + ++NumCounterOverflows; + break; + case instrprof_error::value_site_count_mismatch: + ++NumValueSiteCountMismatches; + break; + default: + llvm_unreachable("Not a soft error"); + } +} + +std::string InstrProfError::message() const { + return getInstrProfErrString(Err); +} + +char InstrProfError::ID = 0; + +std::string getPGOFuncName(StringRef RawFuncName, + GlobalValue::LinkageTypes Linkage, + StringRef FileName, + uint64_t Version LLVM_ATTRIBUTE_UNUSED) { + return GlobalValue::getGlobalIdentifier(RawFuncName, Linkage, FileName); +} + +// Strip NumPrefix level of directory name from PathNameStr. If the number of +// directory separators is less than NumPrefix, strip all the directories and +// leave base file name only. +static StringRef stripDirPrefix(StringRef PathNameStr, uint32_t NumPrefix) { + uint32_t Count = NumPrefix; + uint32_t Pos = 0, LastPos = 0; + for (auto & CI : PathNameStr) { + ++Pos; + if (llvm::sys::path::is_separator(CI)) { + LastPos = Pos; + --Count; + } + if (Count == 0) + break; + } + return PathNameStr.substr(LastPos); +} + +// Return the PGOFuncName. This function has some special handling when called +// in LTO optimization. The following only applies when calling in LTO passes +// (when \c InLTO is true): LTO's internalization privatizes many global linkage +// symbols. This happens after value profile annotation, but those internal +// linkage functions should not have a source prefix. +// Additionally, for ThinLTO mode, exported internal functions are promoted +// and renamed. We need to ensure that the original internal PGO name is +// used when computing the GUID that is compared against the profiled GUIDs. +// To differentiate compiler generated internal symbols from original ones, +// PGOFuncName meta data are created and attached to the original internal +// symbols in the value profile annotation step +// (PGOUseFunc::annotateIndirectCallSites). If a symbol does not have the meta +// data, its original linkage must be non-internal. +std::string getPGOFuncName(const Function &F, bool InLTO, uint64_t Version) { + if (!InLTO) { + StringRef FileName(F.getParent()->getSourceFileName()); + uint32_t StripLevel = StaticFuncFullModulePrefix ? 0 : (uint32_t)-1; + if (StripLevel < StaticFuncStripDirNamePrefix) + StripLevel = StaticFuncStripDirNamePrefix; + if (StripLevel) + FileName = stripDirPrefix(FileName, StripLevel); + return getPGOFuncName(F.getName(), F.getLinkage(), FileName, Version); + } + + // In LTO mode (when InLTO is true), first check if there is a meta data. + if (MDNode *MD = getPGOFuncNameMetadata(F)) { + StringRef S = cast<MDString>(MD->getOperand(0))->getString(); + return S.str(); + } + + // If there is no meta data, the function must be a global before the value + // profile annotation pass. Its current linkage may be internal if it is + // internalized in LTO mode. + return getPGOFuncName(F.getName(), GlobalValue::ExternalLinkage, ""); +} + +StringRef getFuncNameWithoutPrefix(StringRef PGOFuncName, StringRef FileName) { + if (FileName.empty()) + return PGOFuncName; + // Drop the file name including ':'. See also getPGOFuncName. + if (PGOFuncName.startswith(FileName)) + PGOFuncName = PGOFuncName.drop_front(FileName.size() + 1); + return PGOFuncName; +} + +// \p FuncName is the string used as profile lookup key for the function. A +// symbol is created to hold the name. Return the legalized symbol name. +std::string getPGOFuncNameVarName(StringRef FuncName, + GlobalValue::LinkageTypes Linkage) { + std::string VarName = getInstrProfNameVarPrefix(); + VarName += FuncName; + + if (!GlobalValue::isLocalLinkage(Linkage)) + return VarName; + + // Now fix up illegal chars in local VarName that may upset the assembler. + const char *InvalidChars = "-:<>/\"'"; + size_t found = VarName.find_first_of(InvalidChars); + while (found != std::string::npos) { + VarName[found] = '_'; + found = VarName.find_first_of(InvalidChars, found + 1); + } + return VarName; +} + +GlobalVariable *createPGOFuncNameVar(Module &M, + GlobalValue::LinkageTypes Linkage, + StringRef PGOFuncName) { + // We generally want to match the function's linkage, but available_externally + // and extern_weak both have the wrong semantics, and anything that doesn't + // need to link across compilation units doesn't need to be visible at all. + if (Linkage == GlobalValue::ExternalWeakLinkage) + Linkage = GlobalValue::LinkOnceAnyLinkage; + else if (Linkage == GlobalValue::AvailableExternallyLinkage) + Linkage = GlobalValue::LinkOnceODRLinkage; + else if (Linkage == GlobalValue::InternalLinkage || + Linkage == GlobalValue::ExternalLinkage) + Linkage = GlobalValue::PrivateLinkage; + + auto *Value = + ConstantDataArray::getString(M.getContext(), PGOFuncName, false); + auto FuncNameVar = + new GlobalVariable(M, Value->getType(), true, Linkage, Value, + getPGOFuncNameVarName(PGOFuncName, Linkage)); + + // Hide the symbol so that we correctly get a copy for each executable. + if (!GlobalValue::isLocalLinkage(FuncNameVar->getLinkage())) + FuncNameVar->setVisibility(GlobalValue::HiddenVisibility); + + return FuncNameVar; +} + +GlobalVariable *createPGOFuncNameVar(Function &F, StringRef PGOFuncName) { + return createPGOFuncNameVar(*F.getParent(), F.getLinkage(), PGOFuncName); +} + +Error InstrProfSymtab::create(Module &M, bool InLTO) { + for (Function &F : M) { + // Function may not have a name: like using asm("") to overwrite the name. + // Ignore in this case. + if (!F.hasName()) + continue; + const std::string &PGOFuncName = getPGOFuncName(F, InLTO); + if (Error E = addFuncName(PGOFuncName)) + return E; + MD5FuncMap.emplace_back(Function::getGUID(PGOFuncName), &F); + // In ThinLTO, local function may have been promoted to global and have + // suffix added to the function name. We need to add the stripped function + // name to the symbol table so that we can find a match from profile. + if (InLTO) { + auto pos = PGOFuncName.find('.'); + if (pos != std::string::npos) { + const std::string &OtherFuncName = PGOFuncName.substr(0, pos); + if (Error E = addFuncName(OtherFuncName)) + return E; + MD5FuncMap.emplace_back(Function::getGUID(OtherFuncName), &F); + } + } + } + Sorted = false; + finalizeSymtab(); + return Error::success(); +} + +uint64_t InstrProfSymtab::getFunctionHashFromAddress(uint64_t Address) { + finalizeSymtab(); + auto It = partition_point(AddrToMD5Map, [=](std::pair<uint64_t, uint64_t> A) { + return A.first < Address; + }); + // Raw function pointer collected by value profiler may be from + // external functions that are not instrumented. They won't have + // mapping data to be used by the deserializer. Force the value to + // be 0 in this case. + if (It != AddrToMD5Map.end() && It->first == Address) + return (uint64_t)It->second; + return 0; +} + +Error collectPGOFuncNameStrings(ArrayRef<std::string> NameStrs, + bool doCompression, std::string &Result) { + assert(!NameStrs.empty() && "No name data to emit"); + + uint8_t Header[16], *P = Header; + std::string UncompressedNameStrings = + join(NameStrs.begin(), NameStrs.end(), getInstrProfNameSeparator()); + + assert(StringRef(UncompressedNameStrings) + .count(getInstrProfNameSeparator()) == (NameStrs.size() - 1) && + "PGO name is invalid (contains separator token)"); + + unsigned EncLen = encodeULEB128(UncompressedNameStrings.length(), P); + P += EncLen; + + auto WriteStringToResult = [&](size_t CompressedLen, StringRef InputStr) { + EncLen = encodeULEB128(CompressedLen, P); + P += EncLen; + char *HeaderStr = reinterpret_cast<char *>(&Header[0]); + unsigned HeaderLen = P - &Header[0]; + Result.append(HeaderStr, HeaderLen); + Result += InputStr; + return Error::success(); + }; + + if (!doCompression) { + return WriteStringToResult(0, UncompressedNameStrings); + } + + SmallString<128> CompressedNameStrings; + Error E = zlib::compress(StringRef(UncompressedNameStrings), + CompressedNameStrings, zlib::BestSizeCompression); + if (E) { + consumeError(std::move(E)); + return make_error<InstrProfError>(instrprof_error::compress_failed); + } + + return WriteStringToResult(CompressedNameStrings.size(), + CompressedNameStrings); +} + +StringRef getPGOFuncNameVarInitializer(GlobalVariable *NameVar) { + auto *Arr = cast<ConstantDataArray>(NameVar->getInitializer()); + StringRef NameStr = + Arr->isCString() ? Arr->getAsCString() : Arr->getAsString(); + return NameStr; +} + +Error collectPGOFuncNameStrings(ArrayRef<GlobalVariable *> NameVars, + std::string &Result, bool doCompression) { + std::vector<std::string> NameStrs; + for (auto *NameVar : NameVars) { + NameStrs.push_back(getPGOFuncNameVarInitializer(NameVar)); + } + return collectPGOFuncNameStrings( + NameStrs, zlib::isAvailable() && doCompression, Result); +} + +Error readPGOFuncNameStrings(StringRef NameStrings, InstrProfSymtab &Symtab) { + const uint8_t *P = NameStrings.bytes_begin(); + const uint8_t *EndP = NameStrings.bytes_end(); + while (P < EndP) { + uint32_t N; + uint64_t UncompressedSize = decodeULEB128(P, &N); + P += N; + uint64_t CompressedSize = decodeULEB128(P, &N); + P += N; + bool isCompressed = (CompressedSize != 0); + SmallString<128> UncompressedNameStrings; + StringRef NameStrings; + if (isCompressed) { + if (!llvm::zlib::isAvailable()) + return make_error<InstrProfError>(instrprof_error::zlib_unavailable); + + StringRef CompressedNameStrings(reinterpret_cast<const char *>(P), + CompressedSize); + if (Error E = + zlib::uncompress(CompressedNameStrings, UncompressedNameStrings, + UncompressedSize)) { + consumeError(std::move(E)); + return make_error<InstrProfError>(instrprof_error::uncompress_failed); + } + P += CompressedSize; + NameStrings = StringRef(UncompressedNameStrings.data(), + UncompressedNameStrings.size()); + } else { + NameStrings = + StringRef(reinterpret_cast<const char *>(P), UncompressedSize); + P += UncompressedSize; + } + // Now parse the name strings. + SmallVector<StringRef, 0> Names; + NameStrings.split(Names, getInstrProfNameSeparator()); + for (StringRef &Name : Names) + if (Error E = Symtab.addFuncName(Name)) + return E; + + while (P < EndP && *P == 0) + P++; + } + return Error::success(); +} + +void InstrProfRecord::accumulateCounts(CountSumOrPercent &Sum) const { + uint64_t FuncSum = 0; + Sum.NumEntries += Counts.size(); + for (size_t F = 0, E = Counts.size(); F < E; ++F) + FuncSum += Counts[F]; + Sum.CountSum += FuncSum; + + for (uint32_t VK = IPVK_First; VK <= IPVK_Last; ++VK) { + uint64_t KindSum = 0; + uint32_t NumValueSites = getNumValueSites(VK); + for (size_t I = 0; I < NumValueSites; ++I) { + uint32_t NV = getNumValueDataForSite(VK, I); + std::unique_ptr<InstrProfValueData[]> VD = getValueForSite(VK, I); + for (uint32_t V = 0; V < NV; V++) + KindSum += VD[V].Count; + } + Sum.ValueCounts[VK] += KindSum; + } +} + +void InstrProfValueSiteRecord::overlap(InstrProfValueSiteRecord &Input, + uint32_t ValueKind, + OverlapStats &Overlap, + OverlapStats &FuncLevelOverlap) { + this->sortByTargetValues(); + Input.sortByTargetValues(); + double Score = 0.0f, FuncLevelScore = 0.0f; + auto I = ValueData.begin(); + auto IE = ValueData.end(); + auto J = Input.ValueData.begin(); + auto JE = Input.ValueData.end(); + while (I != IE && J != JE) { + if (I->Value == J->Value) { + Score += OverlapStats::score(I->Count, J->Count, + Overlap.Base.ValueCounts[ValueKind], + Overlap.Test.ValueCounts[ValueKind]); + FuncLevelScore += OverlapStats::score( + I->Count, J->Count, FuncLevelOverlap.Base.ValueCounts[ValueKind], + FuncLevelOverlap.Test.ValueCounts[ValueKind]); + ++I; + } else if (I->Value < J->Value) { + ++I; + continue; + } + ++J; + } + Overlap.Overlap.ValueCounts[ValueKind] += Score; + FuncLevelOverlap.Overlap.ValueCounts[ValueKind] += FuncLevelScore; +} + +// Return false on mismatch. +void InstrProfRecord::overlapValueProfData(uint32_t ValueKind, + InstrProfRecord &Other, + OverlapStats &Overlap, + OverlapStats &FuncLevelOverlap) { + uint32_t ThisNumValueSites = getNumValueSites(ValueKind); + assert(ThisNumValueSites == Other.getNumValueSites(ValueKind)); + if (!ThisNumValueSites) + return; + + std::vector<InstrProfValueSiteRecord> &ThisSiteRecords = + getOrCreateValueSitesForKind(ValueKind); + MutableArrayRef<InstrProfValueSiteRecord> OtherSiteRecords = + Other.getValueSitesForKind(ValueKind); + for (uint32_t I = 0; I < ThisNumValueSites; I++) + ThisSiteRecords[I].overlap(OtherSiteRecords[I], ValueKind, Overlap, + FuncLevelOverlap); +} + +void InstrProfRecord::overlap(InstrProfRecord &Other, OverlapStats &Overlap, + OverlapStats &FuncLevelOverlap, + uint64_t ValueCutoff) { + // FuncLevel CountSum for other should already computed and nonzero. + assert(FuncLevelOverlap.Test.CountSum >= 1.0f); + accumulateCounts(FuncLevelOverlap.Base); + bool Mismatch = (Counts.size() != Other.Counts.size()); + + // Check if the value profiles mismatch. + if (!Mismatch) { + for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind) { + uint32_t ThisNumValueSites = getNumValueSites(Kind); + uint32_t OtherNumValueSites = Other.getNumValueSites(Kind); + if (ThisNumValueSites != OtherNumValueSites) { + Mismatch = true; + break; + } + } + } + if (Mismatch) { + Overlap.addOneMismatch(FuncLevelOverlap.Test); + return; + } + + // Compute overlap for value counts. + for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind) + overlapValueProfData(Kind, Other, Overlap, FuncLevelOverlap); + + double Score = 0.0; + uint64_t MaxCount = 0; + // Compute overlap for edge counts. + for (size_t I = 0, E = Other.Counts.size(); I < E; ++I) { + Score += OverlapStats::score(Counts[I], Other.Counts[I], + Overlap.Base.CountSum, Overlap.Test.CountSum); + MaxCount = std::max(Other.Counts[I], MaxCount); + } + Overlap.Overlap.CountSum += Score; + Overlap.Overlap.NumEntries += 1; + + if (MaxCount >= ValueCutoff) { + double FuncScore = 0.0; + for (size_t I = 0, E = Other.Counts.size(); I < E; ++I) + FuncScore += OverlapStats::score(Counts[I], Other.Counts[I], + FuncLevelOverlap.Base.CountSum, + FuncLevelOverlap.Test.CountSum); + FuncLevelOverlap.Overlap.CountSum = FuncScore; + FuncLevelOverlap.Overlap.NumEntries = Other.Counts.size(); + FuncLevelOverlap.Valid = true; + } +} + +void InstrProfValueSiteRecord::merge(InstrProfValueSiteRecord &Input, + uint64_t Weight, + function_ref<void(instrprof_error)> Warn) { + this->sortByTargetValues(); + Input.sortByTargetValues(); + auto I = ValueData.begin(); + auto IE = ValueData.end(); + for (auto J = Input.ValueData.begin(), JE = Input.ValueData.end(); J != JE; + ++J) { + while (I != IE && I->Value < J->Value) + ++I; + if (I != IE && I->Value == J->Value) { + bool Overflowed; + I->Count = SaturatingMultiplyAdd(J->Count, Weight, I->Count, &Overflowed); + if (Overflowed) + Warn(instrprof_error::counter_overflow); + ++I; + continue; + } + ValueData.insert(I, *J); + } +} + +void InstrProfValueSiteRecord::scale(uint64_t Weight, + function_ref<void(instrprof_error)> Warn) { + for (auto I = ValueData.begin(), IE = ValueData.end(); I != IE; ++I) { + bool Overflowed; + I->Count = SaturatingMultiply(I->Count, Weight, &Overflowed); + if (Overflowed) + Warn(instrprof_error::counter_overflow); + } +} + +// Merge Value Profile data from Src record to this record for ValueKind. +// Scale merged value counts by \p Weight. +void InstrProfRecord::mergeValueProfData( + uint32_t ValueKind, InstrProfRecord &Src, uint64_t Weight, + function_ref<void(instrprof_error)> Warn) { + uint32_t ThisNumValueSites = getNumValueSites(ValueKind); + uint32_t OtherNumValueSites = Src.getNumValueSites(ValueKind); + if (ThisNumValueSites != OtherNumValueSites) { + Warn(instrprof_error::value_site_count_mismatch); + return; + } + if (!ThisNumValueSites) + return; + std::vector<InstrProfValueSiteRecord> &ThisSiteRecords = + getOrCreateValueSitesForKind(ValueKind); + MutableArrayRef<InstrProfValueSiteRecord> OtherSiteRecords = + Src.getValueSitesForKind(ValueKind); + for (uint32_t I = 0; I < ThisNumValueSites; I++) + ThisSiteRecords[I].merge(OtherSiteRecords[I], Weight, Warn); +} + +void InstrProfRecord::merge(InstrProfRecord &Other, uint64_t Weight, + function_ref<void(instrprof_error)> Warn) { + // If the number of counters doesn't match we either have bad data + // or a hash collision. + if (Counts.size() != Other.Counts.size()) { + Warn(instrprof_error::count_mismatch); + return; + } + + for (size_t I = 0, E = Other.Counts.size(); I < E; ++I) { + bool Overflowed; + Counts[I] = + SaturatingMultiplyAdd(Other.Counts[I], Weight, Counts[I], &Overflowed); + if (Overflowed) + Warn(instrprof_error::counter_overflow); + } + + for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind) + mergeValueProfData(Kind, Other, Weight, Warn); +} + +void InstrProfRecord::scaleValueProfData( + uint32_t ValueKind, uint64_t Weight, + function_ref<void(instrprof_error)> Warn) { + for (auto &R : getValueSitesForKind(ValueKind)) + R.scale(Weight, Warn); +} + +void InstrProfRecord::scale(uint64_t Weight, + function_ref<void(instrprof_error)> Warn) { + for (auto &Count : this->Counts) { + bool Overflowed; + Count = SaturatingMultiply(Count, Weight, &Overflowed); + if (Overflowed) + Warn(instrprof_error::counter_overflow); + } + for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind) + scaleValueProfData(Kind, Weight, Warn); +} + +// Map indirect call target name hash to name string. +uint64_t InstrProfRecord::remapValue(uint64_t Value, uint32_t ValueKind, + InstrProfSymtab *SymTab) { + if (!SymTab) + return Value; + + if (ValueKind == IPVK_IndirectCallTarget) + return SymTab->getFunctionHashFromAddress(Value); + + return Value; +} + +void InstrProfRecord::addValueData(uint32_t ValueKind, uint32_t Site, + InstrProfValueData *VData, uint32_t N, + InstrProfSymtab *ValueMap) { + for (uint32_t I = 0; I < N; I++) { + VData[I].Value = remapValue(VData[I].Value, ValueKind, ValueMap); + } + std::vector<InstrProfValueSiteRecord> &ValueSites = + getOrCreateValueSitesForKind(ValueKind); + if (N == 0) + ValueSites.emplace_back(); + else + ValueSites.emplace_back(VData, VData + N); +} + +#define INSTR_PROF_COMMON_API_IMPL +#include "llvm/ProfileData/InstrProfData.inc" + +/*! + * ValueProfRecordClosure Interface implementation for InstrProfRecord + * class. These C wrappers are used as adaptors so that C++ code can be + * invoked as callbacks. + */ +uint32_t getNumValueKindsInstrProf(const void *Record) { + return reinterpret_cast<const InstrProfRecord *>(Record)->getNumValueKinds(); +} + +uint32_t getNumValueSitesInstrProf(const void *Record, uint32_t VKind) { + return reinterpret_cast<const InstrProfRecord *>(Record) + ->getNumValueSites(VKind); +} + +uint32_t getNumValueDataInstrProf(const void *Record, uint32_t VKind) { + return reinterpret_cast<const InstrProfRecord *>(Record) + ->getNumValueData(VKind); +} + +uint32_t getNumValueDataForSiteInstrProf(const void *R, uint32_t VK, + uint32_t S) { + return reinterpret_cast<const InstrProfRecord *>(R) + ->getNumValueDataForSite(VK, S); +} + +void getValueForSiteInstrProf(const void *R, InstrProfValueData *Dst, + uint32_t K, uint32_t S) { + reinterpret_cast<const InstrProfRecord *>(R)->getValueForSite(Dst, K, S); +} + +ValueProfData *allocValueProfDataInstrProf(size_t TotalSizeInBytes) { + ValueProfData *VD = + (ValueProfData *)(new (::operator new(TotalSizeInBytes)) ValueProfData()); + memset(VD, 0, TotalSizeInBytes); + return VD; +} + +static ValueProfRecordClosure InstrProfRecordClosure = { + nullptr, + getNumValueKindsInstrProf, + getNumValueSitesInstrProf, + getNumValueDataInstrProf, + getNumValueDataForSiteInstrProf, + nullptr, + getValueForSiteInstrProf, + allocValueProfDataInstrProf}; + +// Wrapper implementation using the closure mechanism. +uint32_t ValueProfData::getSize(const InstrProfRecord &Record) { + auto Closure = InstrProfRecordClosure; + Closure.Record = &Record; + return getValueProfDataSize(&Closure); +} + +// Wrapper implementation using the closure mechanism. +std::unique_ptr<ValueProfData> +ValueProfData::serializeFrom(const InstrProfRecord &Record) { + InstrProfRecordClosure.Record = &Record; + + std::unique_ptr<ValueProfData> VPD( + serializeValueProfDataFrom(&InstrProfRecordClosure, nullptr)); + return VPD; +} + +void ValueProfRecord::deserializeTo(InstrProfRecord &Record, + InstrProfSymtab *SymTab) { + Record.reserveSites(Kind, NumValueSites); + + InstrProfValueData *ValueData = getValueProfRecordValueData(this); + for (uint64_t VSite = 0; VSite < NumValueSites; ++VSite) { + uint8_t ValueDataCount = this->SiteCountArray[VSite]; + Record.addValueData(Kind, VSite, ValueData, ValueDataCount, SymTab); + ValueData += ValueDataCount; + } +} + +// For writing/serializing, Old is the host endianness, and New is +// byte order intended on disk. For Reading/deserialization, Old +// is the on-disk source endianness, and New is the host endianness. +void ValueProfRecord::swapBytes(support::endianness Old, + support::endianness New) { + using namespace support; + + if (Old == New) + return; + + if (getHostEndianness() != Old) { + sys::swapByteOrder<uint32_t>(NumValueSites); + sys::swapByteOrder<uint32_t>(Kind); + } + uint32_t ND = getValueProfRecordNumValueData(this); + InstrProfValueData *VD = getValueProfRecordValueData(this); + + // No need to swap byte array: SiteCountArrray. + for (uint32_t I = 0; I < ND; I++) { + sys::swapByteOrder<uint64_t>(VD[I].Value); + sys::swapByteOrder<uint64_t>(VD[I].Count); + } + if (getHostEndianness() == Old) { + sys::swapByteOrder<uint32_t>(NumValueSites); + sys::swapByteOrder<uint32_t>(Kind); + } +} + +void ValueProfData::deserializeTo(InstrProfRecord &Record, + InstrProfSymtab *SymTab) { + if (NumValueKinds == 0) + return; + + ValueProfRecord *VR = getFirstValueProfRecord(this); + for (uint32_t K = 0; K < NumValueKinds; K++) { + VR->deserializeTo(Record, SymTab); + VR = getValueProfRecordNext(VR); + } +} + +template <class T> +static T swapToHostOrder(const unsigned char *&D, support::endianness Orig) { + using namespace support; + + if (Orig == little) + return endian::readNext<T, little, unaligned>(D); + else + return endian::readNext<T, big, unaligned>(D); +} + +static std::unique_ptr<ValueProfData> allocValueProfData(uint32_t TotalSize) { + return std::unique_ptr<ValueProfData>(new (::operator new(TotalSize)) + ValueProfData()); +} + +Error ValueProfData::checkIntegrity() { + if (NumValueKinds > IPVK_Last + 1) + return make_error<InstrProfError>(instrprof_error::malformed); + // Total size needs to be mulltiple of quadword size. + if (TotalSize % sizeof(uint64_t)) + return make_error<InstrProfError>(instrprof_error::malformed); + + ValueProfRecord *VR = getFirstValueProfRecord(this); + for (uint32_t K = 0; K < this->NumValueKinds; K++) { + if (VR->Kind > IPVK_Last) + return make_error<InstrProfError>(instrprof_error::malformed); + VR = getValueProfRecordNext(VR); + if ((char *)VR - (char *)this > (ptrdiff_t)TotalSize) + return make_error<InstrProfError>(instrprof_error::malformed); + } + return Error::success(); +} + +Expected<std::unique_ptr<ValueProfData>> +ValueProfData::getValueProfData(const unsigned char *D, + const unsigned char *const BufferEnd, + support::endianness Endianness) { + using namespace support; + + if (D + sizeof(ValueProfData) > BufferEnd) + return make_error<InstrProfError>(instrprof_error::truncated); + + const unsigned char *Header = D; + uint32_t TotalSize = swapToHostOrder<uint32_t>(Header, Endianness); + if (D + TotalSize > BufferEnd) + return make_error<InstrProfError>(instrprof_error::too_large); + + std::unique_ptr<ValueProfData> VPD = allocValueProfData(TotalSize); + memcpy(VPD.get(), D, TotalSize); + // Byte swap. + VPD->swapBytesToHost(Endianness); + + Error E = VPD->checkIntegrity(); + if (E) + return std::move(E); + + return std::move(VPD); +} + +void ValueProfData::swapBytesToHost(support::endianness Endianness) { + using namespace support; + + if (Endianness == getHostEndianness()) + return; + + sys::swapByteOrder<uint32_t>(TotalSize); + sys::swapByteOrder<uint32_t>(NumValueKinds); + + ValueProfRecord *VR = getFirstValueProfRecord(this); + for (uint32_t K = 0; K < NumValueKinds; K++) { + VR->swapBytes(Endianness, getHostEndianness()); + VR = getValueProfRecordNext(VR); + } +} + +void ValueProfData::swapBytesFromHost(support::endianness Endianness) { + using namespace support; + + if (Endianness == getHostEndianness()) + return; + + ValueProfRecord *VR = getFirstValueProfRecord(this); + for (uint32_t K = 0; K < NumValueKinds; K++) { + ValueProfRecord *NVR = getValueProfRecordNext(VR); + VR->swapBytes(getHostEndianness(), Endianness); + VR = NVR; + } + sys::swapByteOrder<uint32_t>(TotalSize); + sys::swapByteOrder<uint32_t>(NumValueKinds); +} + +void annotateValueSite(Module &M, Instruction &Inst, + const InstrProfRecord &InstrProfR, + InstrProfValueKind ValueKind, uint32_t SiteIdx, + uint32_t MaxMDCount) { + uint32_t NV = InstrProfR.getNumValueDataForSite(ValueKind, SiteIdx); + if (!NV) + return; + + uint64_t Sum = 0; + std::unique_ptr<InstrProfValueData[]> VD = + InstrProfR.getValueForSite(ValueKind, SiteIdx, &Sum); + + ArrayRef<InstrProfValueData> VDs(VD.get(), NV); + annotateValueSite(M, Inst, VDs, Sum, ValueKind, MaxMDCount); +} + +void annotateValueSite(Module &M, Instruction &Inst, + ArrayRef<InstrProfValueData> VDs, + uint64_t Sum, InstrProfValueKind ValueKind, + uint32_t MaxMDCount) { + LLVMContext &Ctx = M.getContext(); + MDBuilder MDHelper(Ctx); + SmallVector<Metadata *, 3> Vals; + // Tag + Vals.push_back(MDHelper.createString("VP")); + // Value Kind + Vals.push_back(MDHelper.createConstant( + ConstantInt::get(Type::getInt32Ty(Ctx), ValueKind))); + // Total Count + Vals.push_back( + MDHelper.createConstant(ConstantInt::get(Type::getInt64Ty(Ctx), Sum))); + + // Value Profile Data + uint32_t MDCount = MaxMDCount; + for (auto &VD : VDs) { + Vals.push_back(MDHelper.createConstant( + ConstantInt::get(Type::getInt64Ty(Ctx), VD.Value))); + Vals.push_back(MDHelper.createConstant( + ConstantInt::get(Type::getInt64Ty(Ctx), VD.Count))); + if (--MDCount == 0) + break; + } + Inst.setMetadata(LLVMContext::MD_prof, MDNode::get(Ctx, Vals)); +} + +bool getValueProfDataFromInst(const Instruction &Inst, + InstrProfValueKind ValueKind, + uint32_t MaxNumValueData, + InstrProfValueData ValueData[], + uint32_t &ActualNumValueData, uint64_t &TotalC) { + MDNode *MD = Inst.getMetadata(LLVMContext::MD_prof); + if (!MD) + return false; + + unsigned NOps = MD->getNumOperands(); + + if (NOps < 5) + return false; + + // Operand 0 is a string tag "VP": + MDString *Tag = cast<MDString>(MD->getOperand(0)); + if (!Tag) + return false; + + if (!Tag->getString().equals("VP")) + return false; + + // Now check kind: + ConstantInt *KindInt = mdconst::dyn_extract<ConstantInt>(MD->getOperand(1)); + if (!KindInt) + return false; + if (KindInt->getZExtValue() != ValueKind) + return false; + + // Get total count + ConstantInt *TotalCInt = mdconst::dyn_extract<ConstantInt>(MD->getOperand(2)); + if (!TotalCInt) + return false; + TotalC = TotalCInt->getZExtValue(); + + ActualNumValueData = 0; + + for (unsigned I = 3; I < NOps; I += 2) { + if (ActualNumValueData >= MaxNumValueData) + break; + ConstantInt *Value = mdconst::dyn_extract<ConstantInt>(MD->getOperand(I)); + ConstantInt *Count = + mdconst::dyn_extract<ConstantInt>(MD->getOperand(I + 1)); + if (!Value || !Count) + return false; + ValueData[ActualNumValueData].Value = Value->getZExtValue(); + ValueData[ActualNumValueData].Count = Count->getZExtValue(); + ActualNumValueData++; + } + return true; +} + +MDNode *getPGOFuncNameMetadata(const Function &F) { + return F.getMetadata(getPGOFuncNameMetadataName()); +} + +void createPGOFuncNameMetadata(Function &F, StringRef PGOFuncName) { + // Only for internal linkage functions. + if (PGOFuncName == F.getName()) + return; + // Don't create duplicated meta-data. + if (getPGOFuncNameMetadata(F)) + return; + LLVMContext &C = F.getContext(); + MDNode *N = MDNode::get(C, MDString::get(C, PGOFuncName)); + F.setMetadata(getPGOFuncNameMetadataName(), N); +} + +bool needsComdatForCounter(const Function &F, const Module &M) { + if (F.hasComdat()) + return true; + + if (!Triple(M.getTargetTriple()).supportsCOMDAT()) + return false; + + // See createPGOFuncNameVar for more details. To avoid link errors, profile + // counters for function with available_externally linkage needs to be changed + // to linkonce linkage. On ELF based systems, this leads to weak symbols to be + // created. Without using comdat, duplicate entries won't be removed by the + // linker leading to increased data segement size and raw profile size. Even + // worse, since the referenced counter from profile per-function data object + // will be resolved to the common strong definition, the profile counts for + // available_externally functions will end up being duplicated in raw profile + // data. This can result in distorted profile as the counts of those dups + // will be accumulated by the profile merger. + GlobalValue::LinkageTypes Linkage = F.getLinkage(); + if (Linkage != GlobalValue::ExternalWeakLinkage && + Linkage != GlobalValue::AvailableExternallyLinkage) + return false; + + return true; +} + +// Check if INSTR_PROF_RAW_VERSION_VAR is defined. +bool isIRPGOFlagSet(const Module *M) { + auto IRInstrVar = + M->getNamedGlobal(INSTR_PROF_QUOTE(INSTR_PROF_RAW_VERSION_VAR)); + if (!IRInstrVar || IRInstrVar->isDeclaration() || + IRInstrVar->hasLocalLinkage()) + return false; + + // Check if the flag is set. + if (!IRInstrVar->hasInitializer()) + return false; + + auto *InitVal = dyn_cast_or_null<ConstantInt>(IRInstrVar->getInitializer()); + if (!InitVal) + return false; + return (InitVal->getZExtValue() & VARIANT_MASK_IR_PROF) != 0; +} + +// Check if we can safely rename this Comdat function. +bool canRenameComdatFunc(const Function &F, bool CheckAddressTaken) { + if (F.getName().empty()) + return false; + if (!needsComdatForCounter(F, *(F.getParent()))) + return false; + // Unsafe to rename the address-taken function (which can be used in + // function comparison). + if (CheckAddressTaken && F.hasAddressTaken()) + return false; + // Only safe to do if this function may be discarded if it is not used + // in the compilation unit. + if (!GlobalValue::isDiscardableIfUnused(F.getLinkage())) + return false; + + // For AvailableExternallyLinkage functions. + if (!F.hasComdat()) { + assert(F.getLinkage() == GlobalValue::AvailableExternallyLinkage); + return true; + } + return true; +} + +// Parse the value profile options. +void getMemOPSizeRangeFromOption(StringRef MemOPSizeRange, int64_t &RangeStart, + int64_t &RangeLast) { + static const int64_t DefaultMemOPSizeRangeStart = 0; + static const int64_t DefaultMemOPSizeRangeLast = 8; + RangeStart = DefaultMemOPSizeRangeStart; + RangeLast = DefaultMemOPSizeRangeLast; + + if (!MemOPSizeRange.empty()) { + auto Pos = MemOPSizeRange.find(':'); + if (Pos != std::string::npos) { + if (Pos > 0) + MemOPSizeRange.substr(0, Pos).getAsInteger(10, RangeStart); + if (Pos < MemOPSizeRange.size() - 1) + MemOPSizeRange.substr(Pos + 1).getAsInteger(10, RangeLast); + } else + MemOPSizeRange.getAsInteger(10, RangeLast); + } + assert(RangeLast >= RangeStart); +} + +// Create a COMDAT variable INSTR_PROF_RAW_VERSION_VAR to make the runtime +// aware this is an ir_level profile so it can set the version flag. +void createIRLevelProfileFlagVar(Module &M, bool IsCS) { + const StringRef VarName(INSTR_PROF_QUOTE(INSTR_PROF_RAW_VERSION_VAR)); + Type *IntTy64 = Type::getInt64Ty(M.getContext()); + uint64_t ProfileVersion = (INSTR_PROF_RAW_VERSION | VARIANT_MASK_IR_PROF); + if (IsCS) + ProfileVersion |= VARIANT_MASK_CSIR_PROF; + auto IRLevelVersionVariable = new GlobalVariable( + M, IntTy64, true, GlobalValue::WeakAnyLinkage, + Constant::getIntegerValue(IntTy64, APInt(64, ProfileVersion)), VarName); + IRLevelVersionVariable->setVisibility(GlobalValue::DefaultVisibility); + Triple TT(M.getTargetTriple()); + if (TT.supportsCOMDAT()) { + IRLevelVersionVariable->setLinkage(GlobalValue::ExternalLinkage); + IRLevelVersionVariable->setComdat(M.getOrInsertComdat(VarName)); + } +} + +// Create the variable for the profile file name. +void createProfileFileNameVar(Module &M, StringRef InstrProfileOutput) { + if (InstrProfileOutput.empty()) + return; + Constant *ProfileNameConst = + ConstantDataArray::getString(M.getContext(), InstrProfileOutput, true); + GlobalVariable *ProfileNameVar = new GlobalVariable( + M, ProfileNameConst->getType(), true, GlobalValue::WeakAnyLinkage, + ProfileNameConst, INSTR_PROF_QUOTE(INSTR_PROF_PROFILE_NAME_VAR)); + Triple TT(M.getTargetTriple()); + if (TT.supportsCOMDAT()) { + ProfileNameVar->setLinkage(GlobalValue::ExternalLinkage); + ProfileNameVar->setComdat(M.getOrInsertComdat( + StringRef(INSTR_PROF_QUOTE(INSTR_PROF_PROFILE_NAME_VAR)))); + } +} + +Error OverlapStats::accumulateCounts(const std::string &BaseFilename, + const std::string &TestFilename, + bool IsCS) { + auto getProfileSum = [IsCS](const std::string &Filename, + CountSumOrPercent &Sum) -> Error { + auto ReaderOrErr = InstrProfReader::create(Filename); + if (Error E = ReaderOrErr.takeError()) { + return E; + } + auto Reader = std::move(ReaderOrErr.get()); + Reader->accumulateCounts(Sum, IsCS); + return Error::success(); + }; + auto Ret = getProfileSum(BaseFilename, Base); + if (Ret) + return Ret; + Ret = getProfileSum(TestFilename, Test); + if (Ret) + return Ret; + this->BaseFilename = &BaseFilename; + this->TestFilename = &TestFilename; + Valid = true; + return Error::success(); +} + +void OverlapStats::addOneMismatch(const CountSumOrPercent &MismatchFunc) { + Mismatch.NumEntries += 1; + Mismatch.CountSum += MismatchFunc.CountSum / Test.CountSum; + for (unsigned I = 0; I < IPVK_Last - IPVK_First + 1; I++) { + if (Test.ValueCounts[I] >= 1.0f) + Mismatch.ValueCounts[I] += + MismatchFunc.ValueCounts[I] / Test.ValueCounts[I]; + } +} + +void OverlapStats::addOneUnique(const CountSumOrPercent &UniqueFunc) { + Unique.NumEntries += 1; + Unique.CountSum += UniqueFunc.CountSum / Test.CountSum; + for (unsigned I = 0; I < IPVK_Last - IPVK_First + 1; I++) { + if (Test.ValueCounts[I] >= 1.0f) + Unique.ValueCounts[I] += UniqueFunc.ValueCounts[I] / Test.ValueCounts[I]; + } +} + +void OverlapStats::dump(raw_fd_ostream &OS) const { + if (!Valid) + return; + + const char *EntryName = + (Level == ProgramLevel ? "functions" : "edge counters"); + if (Level == ProgramLevel) { + OS << "Profile overlap infomation for base_profile: " << *BaseFilename + << " and test_profile: " << *TestFilename << "\nProgram level:\n"; + } else { + OS << "Function level:\n" + << " Function: " << FuncName << " (Hash=" << FuncHash << ")\n"; + } + + OS << " # of " << EntryName << " overlap: " << Overlap.NumEntries << "\n"; + if (Mismatch.NumEntries) + OS << " # of " << EntryName << " mismatch: " << Mismatch.NumEntries + << "\n"; + if (Unique.NumEntries) + OS << " # of " << EntryName + << " only in test_profile: " << Unique.NumEntries << "\n"; + + OS << " Edge profile overlap: " << format("%.3f%%", Overlap.CountSum * 100) + << "\n"; + if (Mismatch.NumEntries) + OS << " Mismatched count percentage (Edge): " + << format("%.3f%%", Mismatch.CountSum * 100) << "\n"; + if (Unique.NumEntries) + OS << " Percentage of Edge profile only in test_profile: " + << format("%.3f%%", Unique.CountSum * 100) << "\n"; + OS << " Edge profile base count sum: " << format("%.0f", Base.CountSum) + << "\n" + << " Edge profile test count sum: " << format("%.0f", Test.CountSum) + << "\n"; + + for (unsigned I = 0; I < IPVK_Last - IPVK_First + 1; I++) { + if (Base.ValueCounts[I] < 1.0f && Test.ValueCounts[I] < 1.0f) + continue; + char ProfileKindName[20]; + switch (I) { + case IPVK_IndirectCallTarget: + strncpy(ProfileKindName, "IndirectCall", 19); + break; + case IPVK_MemOPSize: + strncpy(ProfileKindName, "MemOP", 19); + break; + default: + snprintf(ProfileKindName, 19, "VP[%d]", I); + break; + } + OS << " " << ProfileKindName + << " profile overlap: " << format("%.3f%%", Overlap.ValueCounts[I] * 100) + << "\n"; + if (Mismatch.NumEntries) + OS << " Mismatched count percentage (" << ProfileKindName + << "): " << format("%.3f%%", Mismatch.ValueCounts[I] * 100) << "\n"; + if (Unique.NumEntries) + OS << " Percentage of " << ProfileKindName + << " profile only in test_profile: " + << format("%.3f%%", Unique.ValueCounts[I] * 100) << "\n"; + OS << " " << ProfileKindName + << " profile base count sum: " << format("%.0f", Base.ValueCounts[I]) + << "\n" + << " " << ProfileKindName + << " profile test count sum: " << format("%.0f", Test.ValueCounts[I]) + << "\n"; + } +} + +} // end namespace llvm |
