diff options
Diffstat (limited to 'llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFX86_64.cpp')
| -rw-r--r-- | llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFX86_64.cpp | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFX86_64.cpp b/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFX86_64.cpp new file mode 100644 index 00000000000..342eb136494 --- /dev/null +++ b/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFX86_64.cpp @@ -0,0 +1,189 @@ +//===-- RuntimeDyldCOFFX86_64.cpp - COFF/X86_64 specific code ---*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// COFF x86_x64 support for MC-JIT runtime dynamic linker. +// +//===----------------------------------------------------------------------===// + +#include "RuntimeDyldCOFFX86_64.h" + +#define DEBUG_TYPE "dyld" + +namespace llvm { + +void RuntimeDyldCOFFX86_64::registerEHFrames() { + if (!MemMgr) + return; + for (auto const &EHFrameSID : UnregisteredEHFrameSections) { + uint8_t *EHFrameAddr = Sections[EHFrameSID].Address; + uint64_t EHFrameLoadAddr = Sections[EHFrameSID].LoadAddress; + size_t EHFrameSize = Sections[EHFrameSID].Size; + MemMgr->registerEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize); + RegisteredEHFrameSections.push_back(EHFrameSID); + } + UnregisteredEHFrameSections.clear(); +} + +void RuntimeDyldCOFFX86_64::deregisterEHFrames() { + // Stub +} + +// The target location for the relocation is described by RE.SectionID and +// RE.Offset. RE.SectionID can be used to find the SectionEntry. Each +// SectionEntry has three members describing its location. +// SectionEntry::Address is the address at which the section has been loaded +// into memory in the current (host) process. SectionEntry::LoadAddress is the +// address that the section will have in the target process. +// SectionEntry::ObjAddress is the address of the bits for this section in the +// original emitted object image (also in the current address space). +// +// Relocations will be applied as if the section were loaded at +// SectionEntry::LoadAddress, but they will be applied at an address based +// on SectionEntry::Address. SectionEntry::ObjAddress will be used to refer to +// Target memory contents if they are required for value calculations. +// +// The Value parameter here is the load address of the symbol for the +// relocation to be applied. For relocations which refer to symbols in the +// current object Value will be the LoadAddress of the section in which +// the symbol resides (RE.Addend provides additional information about the +// symbol location). For external symbols, Value will be the address of the +// symbol in the target address space. +void RuntimeDyldCOFFX86_64::resolveRelocation(const RelocationEntry &RE, + uint64_t Value) { + const SectionEntry &Section = Sections[RE.SectionID]; + uint8_t *Target = Section.Address + RE.Offset; + + switch (RE.RelType) { + + case COFF::IMAGE_REL_AMD64_REL32: + case COFF::IMAGE_REL_AMD64_REL32_1: + case COFF::IMAGE_REL_AMD64_REL32_2: + case COFF::IMAGE_REL_AMD64_REL32_3: + case COFF::IMAGE_REL_AMD64_REL32_4: + case COFF::IMAGE_REL_AMD64_REL32_5: { + uint32_t *TargetAddress = (uint32_t *)Target; + uint64_t FinalAddress = Section.LoadAddress + RE.Offset; + // Delta is the distance from the start of the reloc to the end of the + // instruction with the reloc. + uint64_t Delta = 4 + (RE.RelType - COFF::IMAGE_REL_AMD64_REL32); + Value -= FinalAddress + Delta; + uint64_t Result = Value + RE.Addend; + assert(((int64_t)Result <= INT32_MAX) && "Relocation overflow"); + assert(((int64_t)Result >= INT32_MIN) && "Relocation underflow"); + *TargetAddress = Result; + break; + } + + case COFF::IMAGE_REL_AMD64_ADDR32NB: { + // Note ADDR32NB requires a well-established notion of + // image base. This address must be less than or equal + // to every section's load address, and all sections must be + // within a 32 bit offset from the base. + // + // For now we just set these to zero. + uint32_t *TargetAddress = (uint32_t *)Target; + *TargetAddress = 0; + break; + } + + case COFF::IMAGE_REL_AMD64_ADDR64: { + uint64_t *TargetAddress = (uint64_t *)Target; + *TargetAddress = Value + RE.Addend; + break; + } + + default: + llvm_unreachable("Relocation type not implemented yet!"); + break; + } +} + +relocation_iterator RuntimeDyldCOFFX86_64::processRelocationRef( + unsigned SectionID, relocation_iterator RelI, const ObjectFile &Obj, + ObjSectionToIDMap &ObjSectionToID, StubMap &Stubs) { + + // Find the symbol referred to in the relocation, and + // get its section and offset. + // + // Insist for now that all symbols be resolvable within + // the scope of this object file. + symbol_iterator Symbol = RelI->getSymbol(); + if (Symbol == Obj.symbol_end()) + report_fatal_error("Unknown symbol in relocation"); + unsigned TargetSectionID = 0; + uint64_t TargetOffset = UnknownAddressOrSize; + const COFFObjectFile *COFFObj = cast<COFFObjectFile>(&Obj); + section_iterator SecI(Obj.section_end()); + Symbol->getSection(SecI); + if (SecI == Obj.section_end()) + report_fatal_error("Unknown section in relocation"); + bool IsCode = SecI->isText(); + TargetSectionID = findOrEmitSection(Obj, *SecI, IsCode, ObjSectionToID); + TargetOffset = getSymbolOffset(*Symbol); + + // Determine the Addend used to adjust the relocation value. + uint64_t RelType; + Check(RelI->getType(RelType)); + uint64_t Offset; + Check(RelI->getOffset(Offset)); + uint64_t Addend = 0; + SectionEntry &Section = Sections[SectionID]; + uintptr_t ObjTarget = Section.ObjAddress + Offset; + + switch (RelType) { + + case COFF::IMAGE_REL_AMD64_REL32: + case COFF::IMAGE_REL_AMD64_REL32_1: + case COFF::IMAGE_REL_AMD64_REL32_2: + case COFF::IMAGE_REL_AMD64_REL32_3: + case COFF::IMAGE_REL_AMD64_REL32_4: + case COFF::IMAGE_REL_AMD64_REL32_5: + case COFF::IMAGE_REL_AMD64_ADDR32NB: { + uint32_t *Displacement = (uint32_t *)ObjTarget; + Addend = *Displacement; + break; + } + + case COFF::IMAGE_REL_AMD64_ADDR64: { + uint64_t *Displacement = (uint64_t *)ObjTarget; + Addend = *Displacement; + break; + } + + default: + break; + } + + StringRef TargetName; + Symbol->getName(TargetName); + DEBUG(dbgs() << "\t\tIn Section " << SectionID << " Offset " << Offset + << " RelType: " << RelType << " TargetName: " << TargetName + << " Addend " << Addend << "\n"); + + RelocationEntry RE(SectionID, Offset, RelType, TargetOffset + Addend); + addRelocationForSection(RE, TargetSectionID); + + return ++RelI; +} + +void RuntimeDyldCOFFX86_64::finalizeLoad(const ObjectFile &Obj, + ObjSectionToIDMap &SectionMap) { + // Look for and record the EH frame section IDs. + for (const auto &SectionPair : SectionMap) { + const SectionRef &Section = SectionPair.first; + StringRef Name; + Check(Section.getName(Name)); + // Note unwind info is split across .pdata and .xdata, so this + // may not be sufficiently general for all users. + if (Name == ".xdata") { + UnregisteredEHFrameSections.push_back(SectionPair.second); + } + } +} +} |
