diff options
Diffstat (limited to 'llvm/lib/Object/MachOObjectFile.cpp')
| -rw-r--r-- | llvm/lib/Object/MachOObjectFile.cpp | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/llvm/lib/Object/MachOObjectFile.cpp b/llvm/lib/Object/MachOObjectFile.cpp index c6815ea..7e7e8c4 100644 --- a/llvm/lib/Object/MachOObjectFile.cpp +++ b/llvm/lib/Object/MachOObjectFile.cpp @@ -17,6 +17,7 @@ #include "llvm/ADT/StringSwitch.h" #include "llvm/ADT/Triple.h" #include "llvm/Support/DataExtractor.h" +#include "llvm/Support/Debug.h" #include "llvm/Support/Format.h" #include "llvm/Support/Host.h" #include "llvm/Support/LEB128.h" @@ -1688,6 +1689,177 @@ iterator_range<export_iterator> MachOObjectFile::exports() const { } +MachORebaseEntry::MachORebaseEntry(ArrayRef<uint8_t> Bytes, bool is64Bit) + : Opcodes(Bytes), Ptr(Bytes.begin()), SegmentOffset(0), SegmentIndex(0), + RemainingLoopCount(0), AdvanceAmount(0), RebaseType(0), + PointerSize(is64Bit ? 8 : 4), Malformed(false), Done(false) {} + +void MachORebaseEntry::moveToFirst() { + Ptr = Opcodes.begin(); + moveNext(); +} + +void MachORebaseEntry::moveToEnd() { + Ptr = Opcodes.end(); + RemainingLoopCount = 0; + Done = true; +} + +void MachORebaseEntry::moveNext() { + // If in the middle of some loop, move to next rebasing in loop. + SegmentOffset += AdvanceAmount; + if (RemainingLoopCount) { + --RemainingLoopCount; + return; + } + if (Ptr == Opcodes.end()) { + Done = true; + return; + } + bool More = true; + while (More && !Malformed) { + // Parse next opcode and set up next loop. + uint8_t Byte = *Ptr++; + uint8_t ImmValue = Byte & MachO::REBASE_IMMEDIATE_MASK; + uint8_t Opcode = Byte & MachO::REBASE_OPCODE_MASK; + switch (Opcode) { + case MachO::REBASE_OPCODE_DONE: + More = false; + Done = true; + moveToEnd(); + DEBUG_WITH_TYPE("mach-o-rebase", llvm::dbgs() << "REBASE_OPCODE_DONE\n"); + break; + case MachO::REBASE_OPCODE_SET_TYPE_IMM: + RebaseType = ImmValue; + DEBUG_WITH_TYPE( + "mach-o-rebase", + llvm::dbgs() << "REBASE_OPCODE_SET_TYPE_IMM: " + << "RebaseType=" << (int) RebaseType << "\n"); + break; + case MachO::REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB: + SegmentIndex = ImmValue; + SegmentOffset = readULEB128(); + DEBUG_WITH_TYPE( + "mach-o-rebase", + llvm::dbgs() << "REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB: " + << "SegmentIndex=" << SegmentIndex << ", " + << format("SegmentOffset=0x%06X", SegmentOffset) + << "\n"); + break; + case MachO::REBASE_OPCODE_ADD_ADDR_ULEB: + SegmentOffset += readULEB128(); + DEBUG_WITH_TYPE("mach-o-rebase", + llvm::dbgs() << "REBASE_OPCODE_ADD_ADDR_ULEB: " + << format("SegmentOffset=0x%06X", + SegmentOffset) << "\n"); + break; + case MachO::REBASE_OPCODE_ADD_ADDR_IMM_SCALED: + SegmentOffset += ImmValue * PointerSize; + DEBUG_WITH_TYPE("mach-o-rebase", + llvm::dbgs() << "REBASE_OPCODE_ADD_ADDR_IMM_SCALED: " + << format("SegmentOffset=0x%06X", + SegmentOffset) << "\n"); + break; + case MachO::REBASE_OPCODE_DO_REBASE_IMM_TIMES: + AdvanceAmount = PointerSize; + RemainingLoopCount = ImmValue - 1; + DEBUG_WITH_TYPE( + "mach-o-rebase", + llvm::dbgs() << "REBASE_OPCODE_DO_REBASE_IMM_TIMES: " + << format("SegmentOffset=0x%06X", SegmentOffset) + << ", AdvanceAmount=" << AdvanceAmount + << ", RemainingLoopCount=" << RemainingLoopCount + << "\n"); + return; + case MachO::REBASE_OPCODE_DO_REBASE_ULEB_TIMES: + AdvanceAmount = PointerSize; + RemainingLoopCount = readULEB128() - 1; + DEBUG_WITH_TYPE( + "mach-o-rebase", + llvm::dbgs() << "REBASE_OPCODE_DO_REBASE_ULEB_TIMES: " + << format("SegmentOffset=0x%06X", SegmentOffset) + << ", AdvanceAmount=" << AdvanceAmount + << ", RemainingLoopCount=" << RemainingLoopCount + << "\n"); + return; + case MachO::REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB: + AdvanceAmount = readULEB128() + PointerSize; + RemainingLoopCount = 0; + DEBUG_WITH_TYPE( + "mach-o-rebase", + llvm::dbgs() << "REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB: " + << format("SegmentOffset=0x%06X", SegmentOffset) + << ", AdvanceAmount=" << AdvanceAmount + << ", RemainingLoopCount=" << RemainingLoopCount + << "\n"); + return; + case MachO::REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_ULEB: + RemainingLoopCount = readULEB128() - 1; + AdvanceAmount = readULEB128() + PointerSize; + DEBUG_WITH_TYPE( + "mach-o-rebase", + llvm::dbgs() << "REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_ULEB: " + << format("SegmentOffset=0x%06X", SegmentOffset) + << ", AdvanceAmount=" << AdvanceAmount + << ", RemainingLoopCount=" << RemainingLoopCount + << "\n"); + return; + default: + Malformed = true; + } + } +} + +uint64_t MachORebaseEntry::readULEB128() { + unsigned Count; + uint64_t Result = decodeULEB128(Ptr, &Count); + Ptr += Count; + if (Ptr > Opcodes.end()) { + Ptr = Opcodes.end(); + Malformed = true; + } + return Result; +} + +uint32_t MachORebaseEntry::segmentIndex() const { return SegmentIndex; } + +uint64_t MachORebaseEntry::segmentOffset() const { return SegmentOffset; } + +StringRef MachORebaseEntry::typeName() const { + switch (RebaseType) { + case MachO::REBASE_TYPE_POINTER: + return "pointer"; + case MachO::REBASE_TYPE_TEXT_ABSOLUTE32: + return "text abs32"; + case MachO::REBASE_TYPE_TEXT_PCREL32: + return "text rel32"; + } + return "unknown"; +} + +bool MachORebaseEntry::operator==(const MachORebaseEntry &Other) const { + assert(Opcodes == Other.Opcodes && "compare iterators of different files"); + return (Ptr == Other.Ptr) && + (RemainingLoopCount == Other.RemainingLoopCount) && + (Done == Other.Done); +} + +iterator_range<rebase_iterator> +MachOObjectFile::rebaseTable(ArrayRef<uint8_t> Opcodes, bool is64) { + MachORebaseEntry Start(Opcodes, is64); + Start.moveToFirst(); + + MachORebaseEntry Finish(Opcodes, is64); + Finish.moveToEnd(); + + return iterator_range<rebase_iterator>(rebase_iterator(Start), + rebase_iterator(Finish)); +} + +iterator_range<rebase_iterator> MachOObjectFile::rebaseTable() const { + return rebaseTable(getDyldInfoRebaseOpcodes(), is64Bit()); +} + StringRef MachOObjectFile::getSectionFinalSegmentName(DataRefImpl Sec) const { ArrayRef<char> Raw = getSectionRawFinalSegmentName(Sec); |