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Diffstat (limited to 'lib/DebugInfo/GSYM/GsymReader.cpp')
| -rw-r--r-- | lib/DebugInfo/GSYM/GsymReader.cpp | 265 |
1 files changed, 265 insertions, 0 deletions
diff --git a/lib/DebugInfo/GSYM/GsymReader.cpp b/lib/DebugInfo/GSYM/GsymReader.cpp new file mode 100644 index 000000000000..1b448cf80b70 --- /dev/null +++ b/lib/DebugInfo/GSYM/GsymReader.cpp @@ -0,0 +1,265 @@ +//===- GsymReader.cpp -----------------------------------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "llvm/DebugInfo/GSYM/GsymReader.h" + +#include <assert.h> +#include <inttypes.h> +#include <stdio.h> +#include <stdlib.h> + +#include "llvm/DebugInfo/GSYM/GsymCreator.h" +#include "llvm/DebugInfo/GSYM/InlineInfo.h" +#include "llvm/DebugInfo/GSYM/LineTable.h" +#include "llvm/Support/BinaryStreamReader.h" +#include "llvm/Support/DataExtractor.h" +#include "llvm/Support/MemoryBuffer.h" + +using namespace llvm; +using namespace gsym; + +GsymReader::GsymReader(std::unique_ptr<MemoryBuffer> Buffer) : + MemBuffer(std::move(Buffer)), + Endian(support::endian::system_endianness()) {} + + GsymReader::GsymReader(GsymReader &&RHS) = default; + +GsymReader::~GsymReader() = default; + +llvm::Expected<GsymReader> GsymReader::openFile(StringRef Filename) { + // Open the input file and return an appropriate error if needed. + ErrorOr<std::unique_ptr<MemoryBuffer>> BuffOrErr = + MemoryBuffer::getFileOrSTDIN(Filename); + auto Err = BuffOrErr.getError(); + if (Err) + return llvm::errorCodeToError(Err); + return create(BuffOrErr.get()); +} + +llvm::Expected<GsymReader> GsymReader::copyBuffer(StringRef Bytes) { + auto MemBuffer = MemoryBuffer::getMemBufferCopy(Bytes, "GSYM bytes"); + return create(MemBuffer); +} + +llvm::Expected<llvm::gsym::GsymReader> +GsymReader::create(std::unique_ptr<MemoryBuffer> &MemBuffer) { + if (!MemBuffer.get()) + return createStringError(std::errc::invalid_argument, + "invalid memory buffer"); + GsymReader GR(std::move(MemBuffer)); + llvm::Error Err = GR.parse(); + if (Err) + return std::move(Err); + return std::move(GR); +} + +llvm::Error +GsymReader::parse() { + BinaryStreamReader FileData(MemBuffer->getBuffer(), + support::endian::system_endianness()); + // Check for the magic bytes. This file format is designed to be mmap'ed + // into a process and accessed as read only. This is done for performance + // and efficiency for symbolicating and parsing GSYM data. + if (FileData.readObject(Hdr)) + return createStringError(std::errc::invalid_argument, + "not enough data for a GSYM header"); + + const auto HostByteOrder = support::endian::system_endianness(); + switch (Hdr->Magic) { + case GSYM_MAGIC: + Endian = HostByteOrder; + break; + case GSYM_CIGAM: + // This is a GSYM file, but not native endianness. + Endian = sys::IsBigEndianHost ? support::little : support::big; + Swap.reset(new SwappedData); + break; + default: + return createStringError(std::errc::invalid_argument, + "not a GSYM file"); + } + + bool DataIsLittleEndian = HostByteOrder != support::little; + // Read a correctly byte swapped header if we need to. + if (Swap) { + DataExtractor Data(MemBuffer->getBuffer(), DataIsLittleEndian, 4); + if (auto ExpectedHdr = Header::decode(Data)) + Swap->Hdr = ExpectedHdr.get(); + else + return ExpectedHdr.takeError(); + Hdr = &Swap->Hdr; + } + + // Detect errors in the header and report any that are found. If we make it + // past this without errors, we know we have a good magic value, a supported + // version number, verified address offset size and a valid UUID size. + if (Error Err = Hdr->checkForError()) + return Err; + + if (!Swap) { + // This is the native endianness case that is most common and optimized for + // efficient lookups. Here we just grab pointers to the native data and + // use ArrayRef objects to allow efficient read only access. + + // Read the address offsets. + if (FileData.padToAlignment(Hdr->AddrOffSize) || + FileData.readArray(AddrOffsets, + Hdr->NumAddresses * Hdr->AddrOffSize)) + return createStringError(std::errc::invalid_argument, + "failed to read address table"); + + // Read the address info offsets. + if (FileData.padToAlignment(4) || + FileData.readArray(AddrInfoOffsets, Hdr->NumAddresses)) + return createStringError(std::errc::invalid_argument, + "failed to read address info offsets table"); + + // Read the file table. + uint32_t NumFiles = 0; + if (FileData.readInteger(NumFiles) || FileData.readArray(Files, NumFiles)) + return createStringError(std::errc::invalid_argument, + "failed to read file table"); + + // Get the string table. + FileData.setOffset(Hdr->StrtabOffset); + if (FileData.readFixedString(StrTab.Data, Hdr->StrtabSize)) + return createStringError(std::errc::invalid_argument, + "failed to read string table"); +} else { + // This is the non native endianness case that is not common and not + // optimized for lookups. Here we decode the important tables into local + // storage and then set the ArrayRef objects to point to these swapped + // copies of the read only data so lookups can be as efficient as possible. + DataExtractor Data(MemBuffer->getBuffer(), DataIsLittleEndian, 4); + + // Read the address offsets. + uint64_t Offset = alignTo(sizeof(Header), Hdr->AddrOffSize); + Swap->AddrOffsets.resize(Hdr->NumAddresses * Hdr->AddrOffSize); + switch (Hdr->AddrOffSize) { + case 1: + if (!Data.getU8(&Offset, Swap->AddrOffsets.data(), Hdr->NumAddresses)) + return createStringError(std::errc::invalid_argument, + "failed to read address table"); + break; + case 2: + if (!Data.getU16(&Offset, + reinterpret_cast<uint16_t *>(Swap->AddrOffsets.data()), + Hdr->NumAddresses)) + return createStringError(std::errc::invalid_argument, + "failed to read address table"); + break; + case 4: + if (!Data.getU32(&Offset, + reinterpret_cast<uint32_t *>(Swap->AddrOffsets.data()), + Hdr->NumAddresses)) + return createStringError(std::errc::invalid_argument, + "failed to read address table"); + break; + case 8: + if (!Data.getU64(&Offset, + reinterpret_cast<uint64_t *>(Swap->AddrOffsets.data()), + Hdr->NumAddresses)) + return createStringError(std::errc::invalid_argument, + "failed to read address table"); + } + AddrOffsets = ArrayRef<uint8_t>(Swap->AddrOffsets); + + // Read the address info offsets. + Offset = alignTo(Offset, 4); + Swap->AddrInfoOffsets.resize(Hdr->NumAddresses); + if (Data.getU32(&Offset, Swap->AddrInfoOffsets.data(), Hdr->NumAddresses)) + AddrInfoOffsets = ArrayRef<uint32_t>(Swap->AddrInfoOffsets); + else + return createStringError(std::errc::invalid_argument, + "failed to read address table"); + // Read the file table. + const uint32_t NumFiles = Data.getU32(&Offset); + if (NumFiles > 0) { + Swap->Files.resize(NumFiles); + if (Data.getU32(&Offset, &Swap->Files[0].Dir, NumFiles*2)) + Files = ArrayRef<FileEntry>(Swap->Files); + else + return createStringError(std::errc::invalid_argument, + "failed to read file table"); + } + // Get the string table. + StrTab.Data = MemBuffer->getBuffer().substr(Hdr->StrtabOffset, + Hdr->StrtabSize); + if (StrTab.Data.empty()) + return createStringError(std::errc::invalid_argument, + "failed to read string table"); + } + return Error::success(); + +} + +const Header &GsymReader::getHeader() const { + // The only way to get a GsymReader is from GsymReader::openFile(...) or + // GsymReader::copyBuffer() and the header must be valid and initialized to + // a valid pointer value, so the assert below should not trigger. + assert(Hdr); + return *Hdr; +} + +Optional<uint64_t> GsymReader::getAddress(size_t Index) const { + switch (Hdr->AddrOffSize) { + case 1: return addressForIndex<uint8_t>(Index); + case 2: return addressForIndex<uint16_t>(Index); + case 4: return addressForIndex<uint32_t>(Index); + case 8: return addressForIndex<uint64_t>(Index); + } + return llvm::None; +} + +Optional<uint64_t> GsymReader::getAddressInfoOffset(size_t Index) const { + const auto NumAddrInfoOffsets = AddrInfoOffsets.size(); + if (Index < NumAddrInfoOffsets) + return AddrInfoOffsets[Index]; + return llvm::None; +} + +Expected<uint64_t> +GsymReader::getAddressIndex(const uint64_t Addr) const { + if (Addr < Hdr->BaseAddress) + return createStringError(std::errc::invalid_argument, + "address 0x%" PRIx64 " not in GSYM", Addr); + const uint64_t AddrOffset = Addr - Hdr->BaseAddress; + switch (Hdr->AddrOffSize) { + case 1: return getAddressOffsetIndex<uint8_t>(AddrOffset); + case 2: return getAddressOffsetIndex<uint16_t>(AddrOffset); + case 4: return getAddressOffsetIndex<uint32_t>(AddrOffset); + case 8: return getAddressOffsetIndex<uint64_t>(AddrOffset); + default: break; + } + return createStringError(std::errc::invalid_argument, + "unsupported address offset size %u", + Hdr->AddrOffSize); +} + +llvm::Expected<FunctionInfo> GsymReader::getFunctionInfo(uint64_t Addr) const { + Expected<uint64_t> AddressIndex = getAddressIndex(Addr); + if (!AddressIndex) + return AddressIndex.takeError(); + // Address info offsets size should have been checked in parse(). + assert(*AddressIndex < AddrInfoOffsets.size()); + auto AddrInfoOffset = AddrInfoOffsets[*AddressIndex]; + DataExtractor Data(MemBuffer->getBuffer().substr(AddrInfoOffset), Endian, 4); + if (Optional<uint64_t> OptAddr = getAddress(*AddressIndex)) { + auto ExpectedFI = FunctionInfo::decode(Data, *OptAddr); + if (ExpectedFI) { + if (ExpectedFI->Range.contains(Addr) || ExpectedFI->Range.size() == 0) + return ExpectedFI; + return createStringError(std::errc::invalid_argument, + "address 0x%" PRIx64 " not in GSYM", Addr); + } + } + return createStringError(std::errc::invalid_argument, + "failed to extract address[%" PRIu64 "]", + *AddressIndex); +} |