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Diffstat (limited to 'lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOI386.h')
| -rw-r--r-- | lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOI386.h | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOI386.h b/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOI386.h new file mode 100644 index 0000000..258b847 --- /dev/null +++ b/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOI386.h @@ -0,0 +1,261 @@ +//===---- RuntimeDyldMachOI386.h ---- MachO/I386 specific code. ---*- C++ -*-=// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_LIB_EXECUTIONENGINE_RUNTIMEDYLD_TARGETS_RUNTIMEDYLDMACHOI386_H +#define LLVM_LIB_EXECUTIONENGINE_RUNTIMEDYLD_TARGETS_RUNTIMEDYLDMACHOI386_H + +#include "../RuntimeDyldMachO.h" + +#define DEBUG_TYPE "dyld" + +namespace llvm { + +class RuntimeDyldMachOI386 + : public RuntimeDyldMachOCRTPBase<RuntimeDyldMachOI386> { +public: + + typedef uint32_t TargetPtrT; + + RuntimeDyldMachOI386(RTDyldMemoryManager *MM) + : RuntimeDyldMachOCRTPBase(MM) {} + + unsigned getMaxStubSize() override { return 0; } + + unsigned getStubAlignment() override { return 1; } + + relocation_iterator + processRelocationRef(unsigned SectionID, relocation_iterator RelI, + ObjectImage &ObjImg, ObjSectionToIDMap &ObjSectionToID, + const SymbolTableMap &Symbols, StubMap &Stubs) override { + const MachOObjectFile &Obj = + static_cast<const MachOObjectFile &>(*ObjImg.getObjectFile()); + MachO::any_relocation_info RelInfo = + Obj.getRelocation(RelI->getRawDataRefImpl()); + uint32_t RelType = Obj.getAnyRelocationType(RelInfo); + + if (Obj.isRelocationScattered(RelInfo)) { + if (RelType == MachO::GENERIC_RELOC_SECTDIFF || + RelType == MachO::GENERIC_RELOC_LOCAL_SECTDIFF) + return processSECTDIFFRelocation(SectionID, RelI, ObjImg, + ObjSectionToID); + else if (RelType == MachO::GENERIC_RELOC_VANILLA) + return processI386ScatteredVANILLA(SectionID, RelI, ObjImg, + ObjSectionToID); + llvm_unreachable("Unhandled scattered relocation."); + } + + RelocationEntry RE(getRelocationEntry(SectionID, ObjImg, RelI)); + RE.Addend = memcpyAddend(RE); + RelocationValueRef Value( + getRelocationValueRef(ObjImg, RelI, RE, ObjSectionToID, Symbols)); + + // Addends for external, PC-rel relocations on i386 point back to the zero + // offset. Calculate the final offset from the relocation target instead. + // This allows us to use the same logic for both external and internal + // relocations in resolveI386RelocationRef. + // bool IsExtern = Obj.getPlainRelocationExternal(RelInfo); + // if (IsExtern && RE.IsPCRel) { + // uint64_t RelocAddr = 0; + // RelI->getAddress(RelocAddr); + // Value.Addend += RelocAddr + 4; + // } + if (RE.IsPCRel) + makeValueAddendPCRel(Value, ObjImg, RelI, 1 << RE.Size); + + RE.Addend = Value.Offset; + + if (Value.SymbolName) + addRelocationForSymbol(RE, Value.SymbolName); + else + addRelocationForSection(RE, Value.SectionID); + + return ++RelI; + } + + void resolveRelocation(const RelocationEntry &RE, uint64_t Value) override { + DEBUG(dumpRelocationToResolve(RE, Value)); + + const SectionEntry &Section = Sections[RE.SectionID]; + uint8_t *LocalAddress = Section.Address + RE.Offset; + + if (RE.IsPCRel) { + uint64_t FinalAddress = Section.LoadAddress + RE.Offset; + Value -= FinalAddress + 4; // see MachOX86_64::resolveRelocation. + } + + switch (RE.RelType) { + default: + llvm_unreachable("Invalid relocation type!"); + case MachO::GENERIC_RELOC_VANILLA: + writeBytesUnaligned(Value + RE.Addend, LocalAddress, 1 << RE.Size); + break; + case MachO::GENERIC_RELOC_SECTDIFF: + case MachO::GENERIC_RELOC_LOCAL_SECTDIFF: { + uint64_t SectionABase = Sections[RE.Sections.SectionA].LoadAddress; + uint64_t SectionBBase = Sections[RE.Sections.SectionB].LoadAddress; + assert((Value == SectionABase || Value == SectionBBase) && + "Unexpected SECTDIFF relocation value."); + Value = SectionABase - SectionBBase + RE.Addend; + writeBytesUnaligned(Value, LocalAddress, 1 << RE.Size); + break; + } + case MachO::GENERIC_RELOC_PB_LA_PTR: + Error("Relocation type not implemented yet!"); + } + } + + void finalizeSection(ObjectImage &ObjImg, unsigned SectionID, + const SectionRef &Section) { + StringRef Name; + Section.getName(Name); + + if (Name == "__jump_table") + populateJumpTable(cast<MachOObjectFile>(*ObjImg.getObjectFile()), Section, + SectionID); + else if (Name == "__pointers") + populateIndirectSymbolPointersSection( + cast<MachOObjectFile>(*ObjImg.getObjectFile()), + Section, SectionID); + } + +private: + relocation_iterator + processSECTDIFFRelocation(unsigned SectionID, relocation_iterator RelI, + ObjectImage &Obj, + ObjSectionToIDMap &ObjSectionToID) { + const MachOObjectFile *MachO = + static_cast<const MachOObjectFile *>(Obj.getObjectFile()); + MachO::any_relocation_info RE = + MachO->getRelocation(RelI->getRawDataRefImpl()); + + SectionEntry &Section = Sections[SectionID]; + uint32_t RelocType = MachO->getAnyRelocationType(RE); + bool IsPCRel = MachO->getAnyRelocationPCRel(RE); + unsigned Size = MachO->getAnyRelocationLength(RE); + uint64_t Offset; + RelI->getOffset(Offset); + uint8_t *LocalAddress = Section.Address + Offset; + unsigned NumBytes = 1 << Size; + uint64_t Addend = readBytesUnaligned(LocalAddress, NumBytes); + + ++RelI; + MachO::any_relocation_info RE2 = + MachO->getRelocation(RelI->getRawDataRefImpl()); + + uint32_t AddrA = MachO->getScatteredRelocationValue(RE); + section_iterator SAI = getSectionByAddress(*MachO, AddrA); + assert(SAI != MachO->section_end() && "Can't find section for address A"); + uint64_t SectionABase = SAI->getAddress(); + uint64_t SectionAOffset = AddrA - SectionABase; + SectionRef SectionA = *SAI; + bool IsCode = SectionA.isText(); + uint32_t SectionAID = + findOrEmitSection(Obj, SectionA, IsCode, ObjSectionToID); + + uint32_t AddrB = MachO->getScatteredRelocationValue(RE2); + section_iterator SBI = getSectionByAddress(*MachO, AddrB); + assert(SBI != MachO->section_end() && "Can't find section for address B"); + uint64_t SectionBBase = SBI->getAddress(); + uint64_t SectionBOffset = AddrB - SectionBBase; + SectionRef SectionB = *SBI; + uint32_t SectionBID = + findOrEmitSection(Obj, SectionB, IsCode, ObjSectionToID); + + if (Addend != AddrA - AddrB) + Error("Unexpected SECTDIFF relocation addend."); + + DEBUG(dbgs() << "Found SECTDIFF: AddrA: " << AddrA << ", AddrB: " << AddrB + << ", Addend: " << Addend << ", SectionA ID: " << SectionAID + << ", SectionAOffset: " << SectionAOffset + << ", SectionB ID: " << SectionBID + << ", SectionBOffset: " << SectionBOffset << "\n"); + RelocationEntry R(SectionID, Offset, RelocType, 0, SectionAID, + SectionAOffset, SectionBID, SectionBOffset, IsPCRel, + Size); + + addRelocationForSection(R, SectionAID); + addRelocationForSection(R, SectionBID); + + return ++RelI; + } + + relocation_iterator processI386ScatteredVANILLA( + unsigned SectionID, relocation_iterator RelI, ObjectImage &Obj, + RuntimeDyldMachO::ObjSectionToIDMap &ObjSectionToID) { + const MachOObjectFile *MachO = + static_cast<const MachOObjectFile *>(Obj.getObjectFile()); + MachO::any_relocation_info RE = + MachO->getRelocation(RelI->getRawDataRefImpl()); + + SectionEntry &Section = Sections[SectionID]; + uint32_t RelocType = MachO->getAnyRelocationType(RE); + bool IsPCRel = MachO->getAnyRelocationPCRel(RE); + unsigned Size = MachO->getAnyRelocationLength(RE); + uint64_t Offset; + RelI->getOffset(Offset); + uint8_t *LocalAddress = Section.Address + Offset; + unsigned NumBytes = 1 << Size; + int64_t Addend = readBytesUnaligned(LocalAddress, NumBytes); + + unsigned SymbolBaseAddr = MachO->getScatteredRelocationValue(RE); + section_iterator TargetSI = getSectionByAddress(*MachO, SymbolBaseAddr); + assert(TargetSI != MachO->section_end() && "Can't find section for symbol"); + uint64_t SectionBaseAddr = TargetSI->getAddress(); + SectionRef TargetSection = *TargetSI; + bool IsCode = TargetSection.isText(); + uint32_t TargetSectionID = + findOrEmitSection(Obj, TargetSection, IsCode, ObjSectionToID); + + Addend -= SectionBaseAddr; + RelocationEntry R(SectionID, Offset, RelocType, Addend, IsPCRel, Size); + + addRelocationForSection(R, TargetSectionID); + + return ++RelI; + } + + // Populate stubs in __jump_table section. + void populateJumpTable(MachOObjectFile &Obj, const SectionRef &JTSection, + unsigned JTSectionID) { + assert(!Obj.is64Bit() && + "__jump_table section not supported in 64-bit MachO."); + + MachO::dysymtab_command DySymTabCmd = Obj.getDysymtabLoadCommand(); + MachO::section Sec32 = Obj.getSection(JTSection.getRawDataRefImpl()); + uint32_t JTSectionSize = Sec32.size; + unsigned FirstIndirectSymbol = Sec32.reserved1; + unsigned JTEntrySize = Sec32.reserved2; + unsigned NumJTEntries = JTSectionSize / JTEntrySize; + uint8_t *JTSectionAddr = getSectionAddress(JTSectionID); + unsigned JTEntryOffset = 0; + + assert((JTSectionSize % JTEntrySize) == 0 && + "Jump-table section does not contain a whole number of stubs?"); + + for (unsigned i = 0; i < NumJTEntries; ++i) { + unsigned SymbolIndex = + Obj.getIndirectSymbolTableEntry(DySymTabCmd, FirstIndirectSymbol + i); + symbol_iterator SI = Obj.getSymbolByIndex(SymbolIndex); + StringRef IndirectSymbolName; + SI->getName(IndirectSymbolName); + uint8_t *JTEntryAddr = JTSectionAddr + JTEntryOffset; + createStubFunction(JTEntryAddr); + RelocationEntry RE(JTSectionID, JTEntryOffset + 1, + MachO::GENERIC_RELOC_VANILLA, 0, true, 2); + addRelocationForSymbol(RE, IndirectSymbolName); + JTEntryOffset += JTEntrySize; + } + } + +}; +} + +#undef DEBUG_TYPE + +#endif |