//===- 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/Config/config.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 #include #include #include #include #include #include #include #include #include using namespace llvm; static cl::opt 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 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::invalid_prof: return "Invalid profile created. Please file a bug " "at: " BUG_REPORT_URL " and include the profraw files that caused this error."; 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(IE)); } }; } // end anonymous namespace static ManagedStatic 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 { cl::opt DoInstrProfNameCompression( "enable-name-compression", cl::desc("Enable name/filename string compression"), cl::init(true)); 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(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 = std::string(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 ".llvm." 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. // // We may have other suffixes similar as ".llvm." which are needed to // be stripped before the matching, but ".__uniq." suffix which is used // to differentiate internal linkage functions in different modules // should be kept. Now this is the only suffix with the pattern ".xxx" // which is kept before matching. const std::string UniqSuffix = ".__uniq."; auto pos = PGOFuncName.find(UniqSuffix); // Search '.' after ".__uniq." if ".__uniq." exists, otherwise // search '.' from the beginning. if (pos != std::string::npos) pos += UniqSuffix.length(); else pos = 0; pos = PGOFuncName.find('.', pos); if (pos != std::string::npos && pos != 0) { 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 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 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(&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(instrprof_error::compress_failed); } return WriteStringToResult(CompressedNameStrings.size(), CompressedNameStrings); } StringRef getPGOFuncNameVarInitializer(GlobalVariable *NameVar) { auto *Arr = cast(NameVar->getInitializer()); StringRef NameStr = Arr->isCString() ? Arr->getAsCString() : Arr->getAsString(); return NameStr; } Error collectPGOFuncNameStrings(ArrayRef NameVars, std::string &Result, bool doCompression) { std::vector NameStrs; for (auto *NameVar : NameVars) { NameStrs.push_back(std::string(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(instrprof_error::zlib_unavailable); StringRef CompressedNameStrings(reinterpret_cast(P), CompressedSize); if (Error E = zlib::uncompress(CompressedNameStrings, UncompressedNameStrings, UncompressedSize)) { consumeError(std::move(E)); return make_error(instrprof_error::uncompress_failed); } P += CompressedSize; NameStrings = StringRef(UncompressedNameStrings.data(), UncompressedNameStrings.size()); } else { NameStrings = StringRef(reinterpret_cast(P), UncompressedSize); P += UncompressedSize; } // Now parse the name strings. SmallVector 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 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 &ThisSiteRecords = getOrCreateValueSitesForKind(ValueKind); MutableArrayRef 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 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 N, uint64_t D, function_ref Warn) { for (auto I = ValueData.begin(), IE = ValueData.end(); I != IE; ++I) { bool Overflowed; I->Count = SaturatingMultiply(I->Count, N, &Overflowed) / D; 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 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 &ThisSiteRecords = getOrCreateValueSitesForKind(ValueKind); MutableArrayRef 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 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 N, uint64_t D, function_ref Warn) { for (auto &R : getValueSitesForKind(ValueKind)) R.scale(N, D, Warn); } void InstrProfRecord::scale(uint64_t N, uint64_t D, function_ref Warn) { assert(D != 0 && "D cannot be 0"); for (auto &Count : this->Counts) { bool Overflowed; Count = SaturatingMultiply(Count, N, &Overflowed) / D; if (Overflowed) Warn(instrprof_error::counter_overflow); } for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind) scaleValueProfData(Kind, N, D, 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 &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(Record)->getNumValueKinds(); } uint32_t getNumValueSitesInstrProf(const void *Record, uint32_t VKind) { return reinterpret_cast(Record) ->getNumValueSites(VKind); } uint32_t getNumValueDataInstrProf(const void *Record, uint32_t VKind) { return reinterpret_cast(Record) ->getNumValueData(VKind); } uint32_t getNumValueDataForSiteInstrProf(const void *R, uint32_t VK, uint32_t S) { return reinterpret_cast(R) ->getNumValueDataForSite(VK, S); } void getValueForSiteInstrProf(const void *R, InstrProfValueData *Dst, uint32_t K, uint32_t S) { reinterpret_cast(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::serializeFrom(const InstrProfRecord &Record) { InstrProfRecordClosure.Record = &Record; std::unique_ptr 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(NumValueSites); sys::swapByteOrder(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(VD[I].Value); sys::swapByteOrder(VD[I].Count); } if (getHostEndianness() == Old) { sys::swapByteOrder(NumValueSites); sys::swapByteOrder(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 static T swapToHostOrder(const unsigned char *&D, support::endianness Orig) { using namespace support; if (Orig == little) return endian::readNext(D); else return endian::readNext(D); } static std::unique_ptr allocValueProfData(uint32_t TotalSize) { return std::unique_ptr(new (::operator new(TotalSize)) ValueProfData()); } Error ValueProfData::checkIntegrity() { if (NumValueKinds > IPVK_Last + 1) return make_error(instrprof_error::malformed); // Total size needs to be mulltiple of quadword size. if (TotalSize % sizeof(uint64_t)) return make_error(instrprof_error::malformed); ValueProfRecord *VR = getFirstValueProfRecord(this); for (uint32_t K = 0; K < this->NumValueKinds; K++) { if (VR->Kind > IPVK_Last) return make_error(instrprof_error::malformed); VR = getValueProfRecordNext(VR); if ((char *)VR - (char *)this > (ptrdiff_t)TotalSize) return make_error(instrprof_error::malformed); } return Error::success(); } Expected> 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(instrprof_error::truncated); const unsigned char *Header = D; uint32_t TotalSize = swapToHostOrder(Header, Endianness); if (D + TotalSize > BufferEnd) return make_error(instrprof_error::too_large); std::unique_ptr 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(TotalSize); sys::swapByteOrder(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(TotalSize); sys::swapByteOrder(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 VD = InstrProfR.getValueForSite(ValueKind, SiteIdx, &Sum); ArrayRef VDs(VD.get(), NV); annotateValueSite(M, Inst, VDs, Sum, ValueKind, MaxMDCount); } void annotateValueSite(Module &M, Instruction &Inst, ArrayRef VDs, uint64_t Sum, InstrProfValueKind ValueKind, uint32_t MaxMDCount) { LLVMContext &Ctx = M.getContext(); MDBuilder MDHelper(Ctx); SmallVector 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, bool GetNoICPValue) { 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(MD->getOperand(0)); if (!Tag) return false; if (!Tag->getString().equals("VP")) return false; // Now check kind: ConstantInt *KindInt = mdconst::dyn_extract(MD->getOperand(1)); if (!KindInt) return false; if (KindInt->getZExtValue() != ValueKind) return false; // Get total count ConstantInt *TotalCInt = mdconst::dyn_extract(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(MD->getOperand(I)); ConstantInt *Count = mdconst::dyn_extract(MD->getOperand(I + 1)); if (!Value || !Count) return false; uint64_t CntValue = Count->getZExtValue(); if (!GetNoICPValue && (CntValue == NOMORE_ICP_MAGICNUM)) continue; ValueData[ActualNumValueData].Value = Value->getZExtValue(); ValueData[ActualNumValueData].Count = CntValue; 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(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; } // 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, bool InstrEntryBBEnabled) { 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; if (InstrEntryBBEnabled) ProfileVersion |= VARIANT_MASK_INSTR_ENTRY; 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