diff options
Diffstat (limited to 'llvm/lib/ProfileData/Coverage/CoverageMappingReader.cpp')
| -rw-r--r-- | llvm/lib/ProfileData/Coverage/CoverageMappingReader.cpp | 831 |
1 files changed, 831 insertions, 0 deletions
diff --git a/llvm/lib/ProfileData/Coverage/CoverageMappingReader.cpp b/llvm/lib/ProfileData/Coverage/CoverageMappingReader.cpp new file mode 100644 index 000000000000..679ff3525eeb --- /dev/null +++ b/llvm/lib/ProfileData/Coverage/CoverageMappingReader.cpp @@ -0,0 +1,831 @@ +//===- CoverageMappingReader.cpp - Code coverage mapping reader -----------===// +// +// 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 reading coverage mapping data for +// instrumentation based coverage. +// +//===----------------------------------------------------------------------===// + +#include "llvm/ProfileData/Coverage/CoverageMappingReader.h" +#include "llvm/ADT/ArrayRef.h" +#include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/ADT/StringRef.h" +#include "llvm/ADT/Triple.h" +#include "llvm/Object/Binary.h" +#include "llvm/Object/Error.h" +#include "llvm/Object/MachOUniversal.h" +#include "llvm/Object/ObjectFile.h" +#include "llvm/Object/COFF.h" +#include "llvm/ProfileData/InstrProf.h" +#include "llvm/Support/Casting.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/Endian.h" +#include "llvm/Support/Error.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/LEB128.h" +#include "llvm/Support/MathExtras.h" +#include "llvm/Support/raw_ostream.h" +#include <vector> + +using namespace llvm; +using namespace coverage; +using namespace object; + +#define DEBUG_TYPE "coverage-mapping" + +void CoverageMappingIterator::increment() { + if (ReadErr != coveragemap_error::success) + return; + + // Check if all the records were read or if an error occurred while reading + // the next record. + if (auto E = Reader->readNextRecord(Record)) + handleAllErrors(std::move(E), [&](const CoverageMapError &CME) { + if (CME.get() == coveragemap_error::eof) + *this = CoverageMappingIterator(); + else + ReadErr = CME.get(); + }); +} + +Error RawCoverageReader::readULEB128(uint64_t &Result) { + if (Data.empty()) + return make_error<CoverageMapError>(coveragemap_error::truncated); + unsigned N = 0; + Result = decodeULEB128(Data.bytes_begin(), &N); + if (N > Data.size()) + return make_error<CoverageMapError>(coveragemap_error::malformed); + Data = Data.substr(N); + return Error::success(); +} + +Error RawCoverageReader::readIntMax(uint64_t &Result, uint64_t MaxPlus1) { + if (auto Err = readULEB128(Result)) + return Err; + if (Result >= MaxPlus1) + return make_error<CoverageMapError>(coveragemap_error::malformed); + return Error::success(); +} + +Error RawCoverageReader::readSize(uint64_t &Result) { + if (auto Err = readULEB128(Result)) + return Err; + // Sanity check the number. + if (Result > Data.size()) + return make_error<CoverageMapError>(coveragemap_error::malformed); + return Error::success(); +} + +Error RawCoverageReader::readString(StringRef &Result) { + uint64_t Length; + if (auto Err = readSize(Length)) + return Err; + Result = Data.substr(0, Length); + Data = Data.substr(Length); + return Error::success(); +} + +Error RawCoverageFilenamesReader::read() { + uint64_t NumFilenames; + if (auto Err = readSize(NumFilenames)) + return Err; + for (size_t I = 0; I < NumFilenames; ++I) { + StringRef Filename; + if (auto Err = readString(Filename)) + return Err; + Filenames.push_back(Filename); + } + return Error::success(); +} + +Error RawCoverageMappingReader::decodeCounter(unsigned Value, Counter &C) { + auto Tag = Value & Counter::EncodingTagMask; + switch (Tag) { + case Counter::Zero: + C = Counter::getZero(); + return Error::success(); + case Counter::CounterValueReference: + C = Counter::getCounter(Value >> Counter::EncodingTagBits); + return Error::success(); + default: + break; + } + Tag -= Counter::Expression; + switch (Tag) { + case CounterExpression::Subtract: + case CounterExpression::Add: { + auto ID = Value >> Counter::EncodingTagBits; + if (ID >= Expressions.size()) + return make_error<CoverageMapError>(coveragemap_error::malformed); + Expressions[ID].Kind = CounterExpression::ExprKind(Tag); + C = Counter::getExpression(ID); + break; + } + default: + return make_error<CoverageMapError>(coveragemap_error::malformed); + } + return Error::success(); +} + +Error RawCoverageMappingReader::readCounter(Counter &C) { + uint64_t EncodedCounter; + if (auto Err = + readIntMax(EncodedCounter, std::numeric_limits<unsigned>::max())) + return Err; + if (auto Err = decodeCounter(EncodedCounter, C)) + return Err; + return Error::success(); +} + +static const unsigned EncodingExpansionRegionBit = 1 + << Counter::EncodingTagBits; + +/// Read the sub-array of regions for the given inferred file id. +/// \param NumFileIDs the number of file ids that are defined for this +/// function. +Error RawCoverageMappingReader::readMappingRegionsSubArray( + std::vector<CounterMappingRegion> &MappingRegions, unsigned InferredFileID, + size_t NumFileIDs) { + uint64_t NumRegions; + if (auto Err = readSize(NumRegions)) + return Err; + unsigned LineStart = 0; + for (size_t I = 0; I < NumRegions; ++I) { + Counter C; + CounterMappingRegion::RegionKind Kind = CounterMappingRegion::CodeRegion; + + // Read the combined counter + region kind. + uint64_t EncodedCounterAndRegion; + if (auto Err = readIntMax(EncodedCounterAndRegion, + std::numeric_limits<unsigned>::max())) + return Err; + unsigned Tag = EncodedCounterAndRegion & Counter::EncodingTagMask; + uint64_t ExpandedFileID = 0; + if (Tag != Counter::Zero) { + if (auto Err = decodeCounter(EncodedCounterAndRegion, C)) + return Err; + } else { + // Is it an expansion region? + if (EncodedCounterAndRegion & EncodingExpansionRegionBit) { + Kind = CounterMappingRegion::ExpansionRegion; + ExpandedFileID = EncodedCounterAndRegion >> + Counter::EncodingCounterTagAndExpansionRegionTagBits; + if (ExpandedFileID >= NumFileIDs) + return make_error<CoverageMapError>(coveragemap_error::malformed); + } else { + switch (EncodedCounterAndRegion >> + Counter::EncodingCounterTagAndExpansionRegionTagBits) { + case CounterMappingRegion::CodeRegion: + // Don't do anything when we have a code region with a zero counter. + break; + case CounterMappingRegion::SkippedRegion: + Kind = CounterMappingRegion::SkippedRegion; + break; + default: + return make_error<CoverageMapError>(coveragemap_error::malformed); + } + } + } + + // Read the source range. + uint64_t LineStartDelta, ColumnStart, NumLines, ColumnEnd; + if (auto Err = + readIntMax(LineStartDelta, std::numeric_limits<unsigned>::max())) + return Err; + if (auto Err = readULEB128(ColumnStart)) + return Err; + if (ColumnStart > std::numeric_limits<unsigned>::max()) + return make_error<CoverageMapError>(coveragemap_error::malformed); + if (auto Err = readIntMax(NumLines, std::numeric_limits<unsigned>::max())) + return Err; + if (auto Err = readIntMax(ColumnEnd, std::numeric_limits<unsigned>::max())) + return Err; + LineStart += LineStartDelta; + + // If the high bit of ColumnEnd is set, this is a gap region. + if (ColumnEnd & (1U << 31)) { + Kind = CounterMappingRegion::GapRegion; + ColumnEnd &= ~(1U << 31); + } + + // Adjust the column locations for the empty regions that are supposed to + // cover whole lines. Those regions should be encoded with the + // column range (1 -> std::numeric_limits<unsigned>::max()), but because + // the encoded std::numeric_limits<unsigned>::max() is several bytes long, + // we set the column range to (0 -> 0) to ensure that the column start and + // column end take up one byte each. + // The std::numeric_limits<unsigned>::max() is used to represent a column + // position at the end of the line without knowing the length of that line. + if (ColumnStart == 0 && ColumnEnd == 0) { + ColumnStart = 1; + ColumnEnd = std::numeric_limits<unsigned>::max(); + } + + LLVM_DEBUG({ + dbgs() << "Counter in file " << InferredFileID << " " << LineStart << ":" + << ColumnStart << " -> " << (LineStart + NumLines) << ":" + << ColumnEnd << ", "; + if (Kind == CounterMappingRegion::ExpansionRegion) + dbgs() << "Expands to file " << ExpandedFileID; + else + CounterMappingContext(Expressions).dump(C, dbgs()); + dbgs() << "\n"; + }); + + auto CMR = CounterMappingRegion(C, InferredFileID, ExpandedFileID, + LineStart, ColumnStart, + LineStart + NumLines, ColumnEnd, Kind); + if (CMR.startLoc() > CMR.endLoc()) + return make_error<CoverageMapError>(coveragemap_error::malformed); + MappingRegions.push_back(CMR); + } + return Error::success(); +} + +Error RawCoverageMappingReader::read() { + // Read the virtual file mapping. + SmallVector<unsigned, 8> VirtualFileMapping; + uint64_t NumFileMappings; + if (auto Err = readSize(NumFileMappings)) + return Err; + for (size_t I = 0; I < NumFileMappings; ++I) { + uint64_t FilenameIndex; + if (auto Err = readIntMax(FilenameIndex, TranslationUnitFilenames.size())) + return Err; + VirtualFileMapping.push_back(FilenameIndex); + } + + // Construct the files using unique filenames and virtual file mapping. + for (auto I : VirtualFileMapping) { + Filenames.push_back(TranslationUnitFilenames[I]); + } + + // Read the expressions. + uint64_t NumExpressions; + if (auto Err = readSize(NumExpressions)) + return Err; + // Create an array of dummy expressions that get the proper counters + // when the expressions are read, and the proper kinds when the counters + // are decoded. + Expressions.resize( + NumExpressions, + CounterExpression(CounterExpression::Subtract, Counter(), Counter())); + for (size_t I = 0; I < NumExpressions; ++I) { + if (auto Err = readCounter(Expressions[I].LHS)) + return Err; + if (auto Err = readCounter(Expressions[I].RHS)) + return Err; + } + + // Read the mapping regions sub-arrays. + for (unsigned InferredFileID = 0, S = VirtualFileMapping.size(); + InferredFileID < S; ++InferredFileID) { + if (auto Err = readMappingRegionsSubArray(MappingRegions, InferredFileID, + VirtualFileMapping.size())) + return Err; + } + + // Set the counters for the expansion regions. + // i.e. Counter of expansion region = counter of the first region + // from the expanded file. + // Perform multiple passes to correctly propagate the counters through + // all the nested expansion regions. + SmallVector<CounterMappingRegion *, 8> FileIDExpansionRegionMapping; + FileIDExpansionRegionMapping.resize(VirtualFileMapping.size(), nullptr); + for (unsigned Pass = 1, S = VirtualFileMapping.size(); Pass < S; ++Pass) { + for (auto &R : MappingRegions) { + if (R.Kind != CounterMappingRegion::ExpansionRegion) + continue; + assert(!FileIDExpansionRegionMapping[R.ExpandedFileID]); + FileIDExpansionRegionMapping[R.ExpandedFileID] = &R; + } + for (auto &R : MappingRegions) { + if (FileIDExpansionRegionMapping[R.FileID]) { + FileIDExpansionRegionMapping[R.FileID]->Count = R.Count; + FileIDExpansionRegionMapping[R.FileID] = nullptr; + } + } + } + + return Error::success(); +} + +Expected<bool> RawCoverageMappingDummyChecker::isDummy() { + // A dummy coverage mapping data consists of just one region with zero count. + uint64_t NumFileMappings; + if (Error Err = readSize(NumFileMappings)) + return std::move(Err); + if (NumFileMappings != 1) + return false; + // We don't expect any specific value for the filename index, just skip it. + uint64_t FilenameIndex; + if (Error Err = + readIntMax(FilenameIndex, std::numeric_limits<unsigned>::max())) + return std::move(Err); + uint64_t NumExpressions; + if (Error Err = readSize(NumExpressions)) + return std::move(Err); + if (NumExpressions != 0) + return false; + uint64_t NumRegions; + if (Error Err = readSize(NumRegions)) + return std::move(Err); + if (NumRegions != 1) + return false; + uint64_t EncodedCounterAndRegion; + if (Error Err = readIntMax(EncodedCounterAndRegion, + std::numeric_limits<unsigned>::max())) + return std::move(Err); + unsigned Tag = EncodedCounterAndRegion & Counter::EncodingTagMask; + return Tag == Counter::Zero; +} + +Error InstrProfSymtab::create(SectionRef &Section) { + Expected<StringRef> DataOrErr = Section.getContents(); + if (!DataOrErr) + return DataOrErr.takeError(); + Data = *DataOrErr; + Address = Section.getAddress(); + + // If this is a linked PE/COFF file, then we have to skip over the null byte + // that is allocated in the .lprfn$A section in the LLVM profiling runtime. + const ObjectFile *Obj = Section.getObject(); + if (isa<COFFObjectFile>(Obj) && !Obj->isRelocatableObject()) + Data = Data.drop_front(1); + + return Error::success(); +} + +StringRef InstrProfSymtab::getFuncName(uint64_t Pointer, size_t Size) { + if (Pointer < Address) + return StringRef(); + auto Offset = Pointer - Address; + if (Offset + Size > Data.size()) + return StringRef(); + return Data.substr(Pointer - Address, Size); +} + +// Check if the mapping data is a dummy, i.e. is emitted for an unused function. +static Expected<bool> isCoverageMappingDummy(uint64_t Hash, StringRef Mapping) { + // The hash value of dummy mapping records is always zero. + if (Hash) + return false; + return RawCoverageMappingDummyChecker(Mapping).isDummy(); +} + +namespace { + +struct CovMapFuncRecordReader { + virtual ~CovMapFuncRecordReader() = default; + + // The interface to read coverage mapping function records for a module. + // + // \p Buf points to the buffer containing the \c CovHeader of the coverage + // mapping data associated with the module. + // + // Returns a pointer to the next \c CovHeader if it exists, or a pointer + // greater than \p End if not. + virtual Expected<const char *> readFunctionRecords(const char *Buf, + const char *End) = 0; + + template <class IntPtrT, support::endianness Endian> + static Expected<std::unique_ptr<CovMapFuncRecordReader>> + get(CovMapVersion Version, InstrProfSymtab &P, + std::vector<BinaryCoverageReader::ProfileMappingRecord> &R, + std::vector<StringRef> &F); +}; + +// A class for reading coverage mapping function records for a module. +template <CovMapVersion Version, class IntPtrT, support::endianness Endian> +class VersionedCovMapFuncRecordReader : public CovMapFuncRecordReader { + using FuncRecordType = + typename CovMapTraits<Version, IntPtrT>::CovMapFuncRecordType; + using NameRefType = typename CovMapTraits<Version, IntPtrT>::NameRefType; + + // Maps function's name references to the indexes of their records + // in \c Records. + DenseMap<NameRefType, size_t> FunctionRecords; + InstrProfSymtab &ProfileNames; + std::vector<StringRef> &Filenames; + std::vector<BinaryCoverageReader::ProfileMappingRecord> &Records; + + // Add the record to the collection if we don't already have a record that + // points to the same function name. This is useful to ignore the redundant + // records for the functions with ODR linkage. + // In addition, prefer records with real coverage mapping data to dummy + // records, which were emitted for inline functions which were seen but + // not used in the corresponding translation unit. + Error insertFunctionRecordIfNeeded(const FuncRecordType *CFR, + StringRef Mapping, size_t FilenamesBegin) { + uint64_t FuncHash = CFR->template getFuncHash<Endian>(); + NameRefType NameRef = CFR->template getFuncNameRef<Endian>(); + auto InsertResult = + FunctionRecords.insert(std::make_pair(NameRef, Records.size())); + if (InsertResult.second) { + StringRef FuncName; + if (Error Err = CFR->template getFuncName<Endian>(ProfileNames, FuncName)) + return Err; + if (FuncName.empty()) + return make_error<InstrProfError>(instrprof_error::malformed); + Records.emplace_back(Version, FuncName, FuncHash, Mapping, FilenamesBegin, + Filenames.size() - FilenamesBegin); + return Error::success(); + } + // Update the existing record if it's a dummy and the new record is real. + size_t OldRecordIndex = InsertResult.first->second; + BinaryCoverageReader::ProfileMappingRecord &OldRecord = + Records[OldRecordIndex]; + Expected<bool> OldIsDummyExpected = isCoverageMappingDummy( + OldRecord.FunctionHash, OldRecord.CoverageMapping); + if (Error Err = OldIsDummyExpected.takeError()) + return Err; + if (!*OldIsDummyExpected) + return Error::success(); + Expected<bool> NewIsDummyExpected = + isCoverageMappingDummy(FuncHash, Mapping); + if (Error Err = NewIsDummyExpected.takeError()) + return Err; + if (*NewIsDummyExpected) + return Error::success(); + OldRecord.FunctionHash = FuncHash; + OldRecord.CoverageMapping = Mapping; + OldRecord.FilenamesBegin = FilenamesBegin; + OldRecord.FilenamesSize = Filenames.size() - FilenamesBegin; + return Error::success(); + } + +public: + VersionedCovMapFuncRecordReader( + InstrProfSymtab &P, + std::vector<BinaryCoverageReader::ProfileMappingRecord> &R, + std::vector<StringRef> &F) + : ProfileNames(P), Filenames(F), Records(R) {} + + ~VersionedCovMapFuncRecordReader() override = default; + + Expected<const char *> readFunctionRecords(const char *Buf, + const char *End) override { + using namespace support; + + if (Buf + sizeof(CovMapHeader) > End) + return make_error<CoverageMapError>(coveragemap_error::malformed); + auto CovHeader = reinterpret_cast<const CovMapHeader *>(Buf); + uint32_t NRecords = CovHeader->getNRecords<Endian>(); + uint32_t FilenamesSize = CovHeader->getFilenamesSize<Endian>(); + uint32_t CoverageSize = CovHeader->getCoverageSize<Endian>(); + assert((CovMapVersion)CovHeader->getVersion<Endian>() == Version); + Buf = reinterpret_cast<const char *>(CovHeader + 1); + + // Skip past the function records, saving the start and end for later. + const char *FunBuf = Buf; + Buf += NRecords * sizeof(FuncRecordType); + const char *FunEnd = Buf; + + // Get the filenames. + if (Buf + FilenamesSize > End) + return make_error<CoverageMapError>(coveragemap_error::malformed); + size_t FilenamesBegin = Filenames.size(); + RawCoverageFilenamesReader Reader(StringRef(Buf, FilenamesSize), Filenames); + if (auto Err = Reader.read()) + return std::move(Err); + Buf += FilenamesSize; + + // We'll read the coverage mapping records in the loop below. + const char *CovBuf = Buf; + Buf += CoverageSize; + const char *CovEnd = Buf; + + if (Buf > End) + return make_error<CoverageMapError>(coveragemap_error::malformed); + // Each coverage map has an alignment of 8, so we need to adjust alignment + // before reading the next map. + Buf += offsetToAlignedAddr(Buf, Align(8)); + + auto CFR = reinterpret_cast<const FuncRecordType *>(FunBuf); + while ((const char *)CFR < FunEnd) { + // Read the function information + uint32_t DataSize = CFR->template getDataSize<Endian>(); + + // Now use that to read the coverage data. + if (CovBuf + DataSize > CovEnd) + return make_error<CoverageMapError>(coveragemap_error::malformed); + auto Mapping = StringRef(CovBuf, DataSize); + CovBuf += DataSize; + + if (Error Err = + insertFunctionRecordIfNeeded(CFR, Mapping, FilenamesBegin)) + return std::move(Err); + CFR++; + } + return Buf; + } +}; + +} // end anonymous namespace + +template <class IntPtrT, support::endianness Endian> +Expected<std::unique_ptr<CovMapFuncRecordReader>> CovMapFuncRecordReader::get( + CovMapVersion Version, InstrProfSymtab &P, + std::vector<BinaryCoverageReader::ProfileMappingRecord> &R, + std::vector<StringRef> &F) { + using namespace coverage; + + switch (Version) { + case CovMapVersion::Version1: + return std::make_unique<VersionedCovMapFuncRecordReader< + CovMapVersion::Version1, IntPtrT, Endian>>(P, R, F); + case CovMapVersion::Version2: + case CovMapVersion::Version3: + // Decompress the name data. + if (Error E = P.create(P.getNameData())) + return std::move(E); + if (Version == CovMapVersion::Version2) + return std::make_unique<VersionedCovMapFuncRecordReader< + CovMapVersion::Version2, IntPtrT, Endian>>(P, R, F); + else + return std::make_unique<VersionedCovMapFuncRecordReader< + CovMapVersion::Version3, IntPtrT, Endian>>(P, R, F); + } + llvm_unreachable("Unsupported version"); +} + +template <typename T, support::endianness Endian> +static Error readCoverageMappingData( + InstrProfSymtab &ProfileNames, StringRef Data, + std::vector<BinaryCoverageReader::ProfileMappingRecord> &Records, + std::vector<StringRef> &Filenames) { + using namespace coverage; + + // Read the records in the coverage data section. + auto CovHeader = + reinterpret_cast<const CovMapHeader *>(Data.data()); + CovMapVersion Version = (CovMapVersion)CovHeader->getVersion<Endian>(); + if (Version > CovMapVersion::CurrentVersion) + return make_error<CoverageMapError>(coveragemap_error::unsupported_version); + Expected<std::unique_ptr<CovMapFuncRecordReader>> ReaderExpected = + CovMapFuncRecordReader::get<T, Endian>(Version, ProfileNames, Records, + Filenames); + if (Error E = ReaderExpected.takeError()) + return E; + auto Reader = std::move(ReaderExpected.get()); + for (const char *Buf = Data.data(), *End = Buf + Data.size(); Buf < End;) { + auto NextHeaderOrErr = Reader->readFunctionRecords(Buf, End); + if (auto E = NextHeaderOrErr.takeError()) + return E; + Buf = NextHeaderOrErr.get(); + } + return Error::success(); +} + +static const char *TestingFormatMagic = "llvmcovmtestdata"; + +Expected<std::unique_ptr<BinaryCoverageReader>> +BinaryCoverageReader::createCoverageReaderFromBuffer( + StringRef Coverage, InstrProfSymtab &&ProfileNames, uint8_t BytesInAddress, + support::endianness Endian) { + std::unique_ptr<BinaryCoverageReader> Reader(new BinaryCoverageReader()); + Reader->ProfileNames = std::move(ProfileNames); + if (BytesInAddress == 4 && Endian == support::endianness::little) { + if (Error E = + readCoverageMappingData<uint32_t, support::endianness::little>( + Reader->ProfileNames, Coverage, Reader->MappingRecords, + Reader->Filenames)) + return std::move(E); + } else if (BytesInAddress == 4 && Endian == support::endianness::big) { + if (Error E = readCoverageMappingData<uint32_t, support::endianness::big>( + Reader->ProfileNames, Coverage, Reader->MappingRecords, + Reader->Filenames)) + return std::move(E); + } else if (BytesInAddress == 8 && Endian == support::endianness::little) { + if (Error E = + readCoverageMappingData<uint64_t, support::endianness::little>( + Reader->ProfileNames, Coverage, Reader->MappingRecords, + Reader->Filenames)) + return std::move(E); + } else if (BytesInAddress == 8 && Endian == support::endianness::big) { + if (Error E = readCoverageMappingData<uint64_t, support::endianness::big>( + Reader->ProfileNames, Coverage, Reader->MappingRecords, + Reader->Filenames)) + return std::move(E); + } else + return make_error<CoverageMapError>(coveragemap_error::malformed); + return std::move(Reader); +} + +static Expected<std::unique_ptr<BinaryCoverageReader>> +loadTestingFormat(StringRef Data) { + uint8_t BytesInAddress = 8; + support::endianness Endian = support::endianness::little; + + Data = Data.substr(StringRef(TestingFormatMagic).size()); + if (Data.empty()) + return make_error<CoverageMapError>(coveragemap_error::truncated); + unsigned N = 0; + uint64_t ProfileNamesSize = decodeULEB128(Data.bytes_begin(), &N); + if (N > Data.size()) + return make_error<CoverageMapError>(coveragemap_error::malformed); + Data = Data.substr(N); + if (Data.empty()) + return make_error<CoverageMapError>(coveragemap_error::truncated); + N = 0; + uint64_t Address = decodeULEB128(Data.bytes_begin(), &N); + if (N > Data.size()) + return make_error<CoverageMapError>(coveragemap_error::malformed); + Data = Data.substr(N); + if (Data.size() < ProfileNamesSize) + return make_error<CoverageMapError>(coveragemap_error::malformed); + InstrProfSymtab ProfileNames; + if (Error E = ProfileNames.create(Data.substr(0, ProfileNamesSize), Address)) + return std::move(E); + StringRef CoverageMapping = Data.substr(ProfileNamesSize); + // Skip the padding bytes because coverage map data has an alignment of 8. + if (CoverageMapping.empty()) + return make_error<CoverageMapError>(coveragemap_error::truncated); + size_t Pad = offsetToAlignedAddr(CoverageMapping.data(), Align(8)); + if (CoverageMapping.size() < Pad) + return make_error<CoverageMapError>(coveragemap_error::malformed); + CoverageMapping = CoverageMapping.substr(Pad); + return BinaryCoverageReader::createCoverageReaderFromBuffer( + CoverageMapping, std::move(ProfileNames), BytesInAddress, Endian); +} + +static Expected<SectionRef> lookupSection(ObjectFile &OF, StringRef Name) { + // On COFF, the object file section name may end in "$M". This tells the + // linker to sort these sections between "$A" and "$Z". The linker removes the + // dollar and everything after it in the final binary. Do the same to match. + bool IsCOFF = isa<COFFObjectFile>(OF); + auto stripSuffix = [IsCOFF](StringRef N) { + return IsCOFF ? N.split('$').first : N; + }; + Name = stripSuffix(Name); + + for (const auto &Section : OF.sections()) { + Expected<StringRef> NameOrErr = Section.getName(); + if (!NameOrErr) + return NameOrErr.takeError(); + if (stripSuffix(*NameOrErr) == Name) + return Section; + } + return make_error<CoverageMapError>(coveragemap_error::no_data_found); +} + +static Expected<std::unique_ptr<BinaryCoverageReader>> +loadBinaryFormat(std::unique_ptr<Binary> Bin, StringRef Arch) { + std::unique_ptr<ObjectFile> OF; + if (auto *Universal = dyn_cast<MachOUniversalBinary>(Bin.get())) { + // If we have a universal binary, try to look up the object for the + // appropriate architecture. + auto ObjectFileOrErr = Universal->getMachOObjectForArch(Arch); + if (!ObjectFileOrErr) + return ObjectFileOrErr.takeError(); + OF = std::move(ObjectFileOrErr.get()); + } else if (isa<ObjectFile>(Bin.get())) { + // For any other object file, upcast and take ownership. + OF.reset(cast<ObjectFile>(Bin.release())); + // If we've asked for a particular arch, make sure they match. + if (!Arch.empty() && OF->getArch() != Triple(Arch).getArch()) + return errorCodeToError(object_error::arch_not_found); + } else + // We can only handle object files. + return make_error<CoverageMapError>(coveragemap_error::malformed); + + // The coverage uses native pointer sizes for the object it's written in. + uint8_t BytesInAddress = OF->getBytesInAddress(); + support::endianness Endian = OF->isLittleEndian() + ? support::endianness::little + : support::endianness::big; + + // Look for the sections that we are interested in. + auto ObjFormat = OF->getTripleObjectFormat(); + auto NamesSection = + lookupSection(*OF, getInstrProfSectionName(IPSK_name, ObjFormat, + /*AddSegmentInfo=*/false)); + if (auto E = NamesSection.takeError()) + return std::move(E); + auto CoverageSection = + lookupSection(*OF, getInstrProfSectionName(IPSK_covmap, ObjFormat, + /*AddSegmentInfo=*/false)); + if (auto E = CoverageSection.takeError()) + return std::move(E); + + // Get the contents of the given sections. + auto CoverageMappingOrErr = CoverageSection->getContents(); + if (!CoverageMappingOrErr) + return CoverageMappingOrErr.takeError(); + + InstrProfSymtab ProfileNames; + if (Error E = ProfileNames.create(*NamesSection)) + return std::move(E); + + return BinaryCoverageReader::createCoverageReaderFromBuffer( + CoverageMappingOrErr.get(), std::move(ProfileNames), BytesInAddress, + Endian); +} + +Expected<std::vector<std::unique_ptr<BinaryCoverageReader>>> +BinaryCoverageReader::create( + MemoryBufferRef ObjectBuffer, StringRef Arch, + SmallVectorImpl<std::unique_ptr<MemoryBuffer>> &ObjectFileBuffers) { + std::vector<std::unique_ptr<BinaryCoverageReader>> Readers; + + if (ObjectBuffer.getBuffer().startswith(TestingFormatMagic)) { + // This is a special format used for testing. + auto ReaderOrErr = loadTestingFormat(ObjectBuffer.getBuffer()); + if (!ReaderOrErr) + return ReaderOrErr.takeError(); + Readers.push_back(std::move(ReaderOrErr.get())); + return std::move(Readers); + } + + auto BinOrErr = createBinary(ObjectBuffer); + if (!BinOrErr) + return BinOrErr.takeError(); + std::unique_ptr<Binary> Bin = std::move(BinOrErr.get()); + + // MachO universal binaries which contain archives need to be treated as + // archives, not as regular binaries. + if (auto *Universal = dyn_cast<MachOUniversalBinary>(Bin.get())) { + for (auto &ObjForArch : Universal->objects()) { + // Skip slices within the universal binary which target the wrong arch. + std::string ObjArch = ObjForArch.getArchFlagName(); + if (Arch != ObjArch) + continue; + + auto ArchiveOrErr = ObjForArch.getAsArchive(); + if (!ArchiveOrErr) { + // If this is not an archive, try treating it as a regular object. + consumeError(ArchiveOrErr.takeError()); + break; + } + + return BinaryCoverageReader::create( + ArchiveOrErr.get()->getMemoryBufferRef(), Arch, ObjectFileBuffers); + } + } + + // Load coverage out of archive members. + if (auto *Ar = dyn_cast<Archive>(Bin.get())) { + Error Err = Error::success(); + for (auto &Child : Ar->children(Err)) { + Expected<MemoryBufferRef> ChildBufOrErr = Child.getMemoryBufferRef(); + if (!ChildBufOrErr) + return ChildBufOrErr.takeError(); + + auto ChildReadersOrErr = BinaryCoverageReader::create( + ChildBufOrErr.get(), Arch, ObjectFileBuffers); + if (!ChildReadersOrErr) + return ChildReadersOrErr.takeError(); + for (auto &Reader : ChildReadersOrErr.get()) + Readers.push_back(std::move(Reader)); + } + if (Err) + return std::move(Err); + + // Thin archives reference object files outside of the archive file, i.e. + // files which reside in memory not owned by the caller. Transfer ownership + // to the caller. + if (Ar->isThin()) + for (auto &Buffer : Ar->takeThinBuffers()) + ObjectFileBuffers.push_back(std::move(Buffer)); + + return std::move(Readers); + } + + auto ReaderOrErr = loadBinaryFormat(std::move(Bin), Arch); + if (!ReaderOrErr) + return ReaderOrErr.takeError(); + Readers.push_back(std::move(ReaderOrErr.get())); + return std::move(Readers); +} + +Error BinaryCoverageReader::readNextRecord(CoverageMappingRecord &Record) { + if (CurrentRecord >= MappingRecords.size()) + return make_error<CoverageMapError>(coveragemap_error::eof); + + FunctionsFilenames.clear(); + Expressions.clear(); + MappingRegions.clear(); + auto &R = MappingRecords[CurrentRecord]; + RawCoverageMappingReader Reader( + R.CoverageMapping, + makeArrayRef(Filenames).slice(R.FilenamesBegin, R.FilenamesSize), + FunctionsFilenames, Expressions, MappingRegions); + if (auto Err = Reader.read()) + return Err; + + Record.FunctionName = R.FunctionName; + Record.FunctionHash = R.FunctionHash; + Record.Filenames = FunctionsFilenames; + Record.Expressions = Expressions; + Record.MappingRegions = MappingRegions; + + ++CurrentRecord; + return Error::success(); +} |