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Diffstat (limited to 'contrib/llvm/lib/ProfileData/CoverageMappingReader.cpp')
-rw-r--r-- | contrib/llvm/lib/ProfileData/CoverageMappingReader.cpp | 550 |
1 files changed, 550 insertions, 0 deletions
diff --git a/contrib/llvm/lib/ProfileData/CoverageMappingReader.cpp b/contrib/llvm/lib/ProfileData/CoverageMappingReader.cpp new file mode 100644 index 0000000..a0f82a0 --- /dev/null +++ b/contrib/llvm/lib/ProfileData/CoverageMappingReader.cpp @@ -0,0 +1,550 @@ +//=-- CoverageMappingReader.cpp - Code coverage mapping reader ----*- C++ -*-=// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file contains support for reading coverage mapping data for +// instrumentation based coverage. +// +//===----------------------------------------------------------------------===// + +#include "llvm/ProfileData/CoverageMappingReader.h" +#include "llvm/ADT/DenseSet.h" +#include "llvm/Object/MachOUniversal.h" +#include "llvm/Object/ObjectFile.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/Endian.h" +#include "llvm/Support/LEB128.h" +#include "llvm/Support/MathExtras.h" +#include "llvm/Support/raw_ostream.h" + +using namespace llvm; +using namespace coverage; +using namespace object; + +#define DEBUG_TYPE "coverage-mapping" + +void CoverageMappingIterator::increment() { + // Check if all the records were read or if an error occurred while reading + // the next record. + if (Reader->readNextRecord(Record)) + *this = CoverageMappingIterator(); +} + +std::error_code RawCoverageReader::readULEB128(uint64_t &Result) { + if (Data.size() < 1) + return coveragemap_error::truncated; + unsigned N = 0; + Result = decodeULEB128(reinterpret_cast<const uint8_t *>(Data.data()), &N); + if (N > Data.size()) + return coveragemap_error::malformed; + Data = Data.substr(N); + return std::error_code(); +} + +std::error_code RawCoverageReader::readIntMax(uint64_t &Result, + uint64_t MaxPlus1) { + if (auto Err = readULEB128(Result)) + return Err; + if (Result >= MaxPlus1) + return coveragemap_error::malformed; + return std::error_code(); +} + +std::error_code RawCoverageReader::readSize(uint64_t &Result) { + if (auto Err = readULEB128(Result)) + return Err; + // Sanity check the number. + if (Result > Data.size()) + return coveragemap_error::malformed; + return std::error_code(); +} + +std::error_code RawCoverageReader::readString(StringRef &Result) { + uint64_t Length; + if (auto Err = readSize(Length)) + return Err; + Result = Data.substr(0, Length); + Data = Data.substr(Length); + return std::error_code(); +} + +std::error_code 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 std::error_code(); +} + +std::error_code RawCoverageMappingReader::decodeCounter(unsigned Value, + Counter &C) { + auto Tag = Value & Counter::EncodingTagMask; + switch (Tag) { + case Counter::Zero: + C = Counter::getZero(); + return std::error_code(); + case Counter::CounterValueReference: + C = Counter::getCounter(Value >> Counter::EncodingTagBits); + return std::error_code(); + default: + break; + } + Tag -= Counter::Expression; + switch (Tag) { + case CounterExpression::Subtract: + case CounterExpression::Add: { + auto ID = Value >> Counter::EncodingTagBits; + if (ID >= Expressions.size()) + return coveragemap_error::malformed; + Expressions[ID].Kind = CounterExpression::ExprKind(Tag); + C = Counter::getExpression(ID); + break; + } + default: + return coveragemap_error::malformed; + } + return std::error_code(); +} + +std::error_code 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 std::error_code(); +} + +static const unsigned EncodingExpansionRegionBit = 1 + << Counter::EncodingTagBits; + +/// \brief 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. +std::error_code 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 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 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 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; + // 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(); + } + + 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"; + }); + + MappingRegions.push_back(CounterMappingRegion( + C, InferredFileID, ExpandedFileID, LineStart, ColumnStart, + LineStart + NumLines, ColumnEnd, Kind)); + } + return std::error_code(); +} + +std::error_code RawCoverageMappingReader::read() { + + // Read the virtual file mapping. + llvm::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 std::error_code(); +} + +std::error_code InstrProfSymtab::create(SectionRef &Section) { + if (auto Err = Section.getContents(Data)) + return Err; + Address = Section.getAddress(); + return std::error_code(); +} + +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); +} + +template <typename T, support::endianness Endian> +static std::error_code readCoverageMappingData( + InstrProfSymtab &ProfileNames, StringRef Data, + std::vector<BinaryCoverageReader::ProfileMappingRecord> &Records, + std::vector<StringRef> &Filenames) { + using namespace support; + llvm::DenseSet<T> UniqueFunctionMappingData; + + // Read the records in the coverage data section. + for (const char *Buf = Data.data(), *End = Buf + Data.size(); Buf < End;) { + if (Buf + 4 * sizeof(uint32_t) > End) + return coveragemap_error::malformed; + uint32_t NRecords = endian::readNext<uint32_t, Endian, unaligned>(Buf); + uint32_t FilenamesSize = endian::readNext<uint32_t, Endian, unaligned>(Buf); + uint32_t CoverageSize = endian::readNext<uint32_t, Endian, unaligned>(Buf); + uint32_t Version = endian::readNext<uint32_t, Endian, unaligned>(Buf); + + switch (Version) { + case CoverageMappingVersion1: + break; + default: + return coveragemap_error::unsupported_version; + } + + // Skip past the function records, saving the start and end for later. + const char *FunBuf = Buf; + Buf += NRecords * sizeof(coverage::CovMapFunctionRecord<T>); + const char *FunEnd = Buf; + + // Get the filenames. + if (Buf + FilenamesSize > End) + return coveragemap_error::malformed; + size_t FilenamesBegin = Filenames.size(); + RawCoverageFilenamesReader Reader(StringRef(Buf, FilenamesSize), Filenames); + if (auto Err = Reader.read()) + return 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 coveragemap_error::malformed; + // Each coverage map has an alignment of 8, so we need to adjust alignment + // before reading the next map. + Buf += alignmentAdjustment(Buf, 8); + + auto CFR = + reinterpret_cast<const coverage::CovMapFunctionRecord<T> *>(FunBuf); + while ((const char *)CFR < FunEnd) { + // Read the function information + T NamePtr = endian::byte_swap<T, Endian>(CFR->NamePtr); + uint32_t NameSize = endian::byte_swap<uint32_t, Endian>(CFR->NameSize); + uint32_t DataSize = endian::byte_swap<uint32_t, Endian>(CFR->DataSize); + uint64_t FuncHash = endian::byte_swap<uint64_t, Endian>(CFR->FuncHash); + CFR++; + + // Now use that to read the coverage data. + if (CovBuf + DataSize > CovEnd) + return coveragemap_error::malformed; + auto Mapping = StringRef(CovBuf, DataSize); + CovBuf += DataSize; + + // Ignore this record if we 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. + if (!UniqueFunctionMappingData.insert(NamePtr).second) + continue; + + // Finally, grab the name and create a record. + StringRef FuncName = ProfileNames.getFuncName(NamePtr, NameSize); + if (NameSize && FuncName.empty()) + return coveragemap_error::malformed; + Records.push_back(BinaryCoverageReader::ProfileMappingRecord( + CoverageMappingVersion(Version), FuncName, FuncHash, Mapping, + FilenamesBegin, Filenames.size() - FilenamesBegin)); + } + } + + return std::error_code(); +} + +static const char *TestingFormatMagic = "llvmcovmtestdata"; + +static std::error_code loadTestingFormat(StringRef Data, + InstrProfSymtab &ProfileNames, + StringRef &CoverageMapping, + uint8_t &BytesInAddress, + support::endianness &Endian) { + BytesInAddress = 8; + Endian = support::endianness::little; + + Data = Data.substr(StringRef(TestingFormatMagic).size()); + if (Data.size() < 1) + return coveragemap_error::truncated; + unsigned N = 0; + auto ProfileNamesSize = + decodeULEB128(reinterpret_cast<const uint8_t *>(Data.data()), &N); + if (N > Data.size()) + return coveragemap_error::malformed; + Data = Data.substr(N); + if (Data.size() < 1) + return coveragemap_error::truncated; + N = 0; + uint64_t Address = + decodeULEB128(reinterpret_cast<const uint8_t *>(Data.data()), &N); + if (N > Data.size()) + return coveragemap_error::malformed; + Data = Data.substr(N); + if (Data.size() < ProfileNamesSize) + return coveragemap_error::malformed; + ProfileNames.create(Data.substr(0, ProfileNamesSize), Address); + CoverageMapping = Data.substr(ProfileNamesSize); + return std::error_code(); +} + +static ErrorOr<SectionRef> lookupSection(ObjectFile &OF, StringRef Name) { + StringRef FoundName; + for (const auto &Section : OF.sections()) { + if (auto EC = Section.getName(FoundName)) + return EC; + if (FoundName == Name) + return Section; + } + return coveragemap_error::no_data_found; +} + +static std::error_code +loadBinaryFormat(MemoryBufferRef ObjectBuffer, InstrProfSymtab &ProfileNames, + StringRef &CoverageMapping, uint8_t &BytesInAddress, + support::endianness &Endian, StringRef Arch) { + auto BinOrErr = object::createBinary(ObjectBuffer); + if (std::error_code EC = BinOrErr.getError()) + return EC; + auto Bin = std::move(BinOrErr.get()); + std::unique_ptr<ObjectFile> OF; + if (auto *Universal = dyn_cast<object::MachOUniversalBinary>(Bin.get())) { + // If we have a universal binary, try to look up the object for the + // appropriate architecture. + auto ObjectFileOrErr = Universal->getObjectForArch(Arch); + if (std::error_code EC = ObjectFileOrErr.getError()) + return EC; + OF = std::move(ObjectFileOrErr.get()); + } else if (isa<object::ObjectFile>(Bin.get())) { + // For any other object file, upcast and take ownership. + OF.reset(cast<object::ObjectFile>(Bin.release())); + // If we've asked for a particular arch, make sure they match. + if (!Arch.empty() && OF->getArch() != Triple(Arch).getArch()) + return object_error::arch_not_found; + } else + // We can only handle object files. + return coveragemap_error::malformed; + + // The coverage uses native pointer sizes for the object it's written in. + BytesInAddress = OF->getBytesInAddress(); + Endian = OF->isLittleEndian() ? support::endianness::little + : support::endianness::big; + + // Look for the sections that we are interested in. + auto NamesSection = lookupSection(*OF, getInstrProfNameSectionName(false)); + if (auto EC = NamesSection.getError()) + return EC; + auto CoverageSection = + lookupSection(*OF, getInstrProfCoverageSectionName(false)); + if (auto EC = CoverageSection.getError()) + return EC; + + // Get the contents of the given sections. + if (std::error_code EC = CoverageSection->getContents(CoverageMapping)) + return EC; + if (std::error_code EC = ProfileNames.create(*NamesSection)) + return EC; + + return std::error_code(); +} + +ErrorOr<std::unique_ptr<BinaryCoverageReader>> +BinaryCoverageReader::create(std::unique_ptr<MemoryBuffer> &ObjectBuffer, + StringRef Arch) { + std::unique_ptr<BinaryCoverageReader> Reader(new BinaryCoverageReader()); + + InstrProfSymtab ProfileNames; + StringRef Coverage; + uint8_t BytesInAddress; + support::endianness Endian; + std::error_code EC; + if (ObjectBuffer->getBuffer().startswith(TestingFormatMagic)) + // This is a special format used for testing. + EC = loadTestingFormat(ObjectBuffer->getBuffer(), ProfileNames, Coverage, + BytesInAddress, Endian); + else + EC = loadBinaryFormat(ObjectBuffer->getMemBufferRef(), ProfileNames, + Coverage, BytesInAddress, Endian, Arch); + if (EC) + return EC; + + if (BytesInAddress == 4 && Endian == support::endianness::little) + EC = readCoverageMappingData<uint32_t, support::endianness::little>( + ProfileNames, Coverage, Reader->MappingRecords, Reader->Filenames); + else if (BytesInAddress == 4 && Endian == support::endianness::big) + EC = readCoverageMappingData<uint32_t, support::endianness::big>( + ProfileNames, Coverage, Reader->MappingRecords, Reader->Filenames); + else if (BytesInAddress == 8 && Endian == support::endianness::little) + EC = readCoverageMappingData<uint64_t, support::endianness::little>( + ProfileNames, Coverage, Reader->MappingRecords, Reader->Filenames); + else if (BytesInAddress == 8 && Endian == support::endianness::big) + EC = readCoverageMappingData<uint64_t, support::endianness::big>( + ProfileNames, Coverage, Reader->MappingRecords, Reader->Filenames); + else + return coveragemap_error::malformed; + if (EC) + return EC; + return std::move(Reader); +} + +std::error_code +BinaryCoverageReader::readNextRecord(CoverageMappingRecord &Record) { + if (CurrentRecord >= MappingRecords.size()) + return 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 std::error_code(); +} |