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Diffstat (limited to 'contrib/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOARM.h')
-rw-r--r-- | contrib/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOARM.h | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/contrib/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOARM.h b/contrib/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOARM.h new file mode 100644 index 000000000000..1de994219824 --- /dev/null +++ b/contrib/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOARM.h @@ -0,0 +1,154 @@ +//===----- RuntimeDyldMachOARM.h ---- MachO/ARM 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_RUNTIMEDYLDMACHOARM_H +#define LLVM_RUNTIMEDYLDMACHOARM_H + +#include "../RuntimeDyldMachO.h" + +#define DEBUG_TYPE "dyld" + +namespace llvm { + +class RuntimeDyldMachOARM + : public RuntimeDyldMachOCRTPBase<RuntimeDyldMachOARM> { +public: + RuntimeDyldMachOARM(RTDyldMemoryManager *MM) : RuntimeDyldMachOCRTPBase(MM) {} + + unsigned getMaxStubSize() override { return 8; } + + unsigned getStubAlignment() override { return 4; } + + 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()); + + if (Obj.isRelocationScattered(RelInfo)) + return ++++RelI; + + RelocationEntry RE(getBasicRelocationEntry(SectionID, ObjImg, RelI)); + RelocationValueRef Value( + getRelocationValueRef(ObjImg, RelI, RE, ObjSectionToID, Symbols)); + + bool IsExtern = Obj.getPlainRelocationExternal(RelInfo); + if (!IsExtern && RE.IsPCRel) + makeValueAddendPCRel(Value, ObjImg, RelI); + + if ((RE.RelType & 0xf) == MachO::ARM_RELOC_BR24) + processBranchRelocation(RE, Value, Stubs); + else { + RE.Addend = Value.Addend; + if (Value.SymbolName) + addRelocationForSymbol(RE, Value.SymbolName); + else + addRelocationForSection(RE, Value.SectionID); + } + + return ++RelI; + } + + void resolveRelocation(const RelocationEntry &RE, uint64_t Value) { + DEBUG(dumpRelocationToResolve(RE, Value)); + const SectionEntry &Section = Sections[RE.SectionID]; + uint8_t *LocalAddress = Section.Address + RE.Offset; + + // If the relocation is PC-relative, the value to be encoded is the + // pointer difference. + if (RE.IsPCRel) { + uint64_t FinalAddress = Section.LoadAddress + RE.Offset; + Value -= FinalAddress; + // ARM PCRel relocations have an effective-PC offset of two instructions + // (four bytes in Thumb mode, 8 bytes in ARM mode). + // FIXME: For now, assume ARM mode. + Value -= 8; + } + + switch (RE.RelType) { + default: + llvm_unreachable("Invalid relocation type!"); + case MachO::ARM_RELOC_VANILLA: + writeBytesUnaligned(LocalAddress, Value, 1 << RE.Size); + break; + case MachO::ARM_RELOC_BR24: { + // Mask the value into the target address. We know instructions are + // 32-bit aligned, so we can do it all at once. + uint32_t *p = (uint32_t *)LocalAddress; + // The low two bits of the value are not encoded. + Value >>= 2; + // Mask the value to 24 bits. + uint64_t FinalValue = Value & 0xffffff; + // Check for overflow. + if (Value != FinalValue) { + Error("ARM BR24 relocation out of range."); + return; + } + // FIXME: If the destination is a Thumb function (and the instruction + // is a non-predicated BL instruction), we need to change it to a BLX + // instruction instead. + + // Insert the value into the instruction. + *p = (*p & ~0xffffff) | FinalValue; + break; + } + case MachO::ARM_THUMB_RELOC_BR22: + case MachO::ARM_THUMB_32BIT_BRANCH: + case MachO::ARM_RELOC_HALF: + case MachO::ARM_RELOC_HALF_SECTDIFF: + case MachO::ARM_RELOC_PAIR: + case MachO::ARM_RELOC_SECTDIFF: + case MachO::ARM_RELOC_LOCAL_SECTDIFF: + case MachO::ARM_RELOC_PB_LA_PTR: + Error("Relocation type not implemented yet!"); + return; + } + } + + void finalizeSection(ObjectImage &ObjImg, unsigned SectionID, + const SectionRef &Section) {} + +private: + void processBranchRelocation(const RelocationEntry &RE, + const RelocationValueRef &Value, + StubMap &Stubs) { + // This is an ARM branch relocation, need to use a stub function. + // Look up for existing stub. + SectionEntry &Section = Sections[RE.SectionID]; + RuntimeDyldMachO::StubMap::const_iterator i = Stubs.find(Value); + uint8_t *Addr; + if (i != Stubs.end()) { + Addr = Section.Address + i->second; + } else { + // Create a new stub function. + Stubs[Value] = Section.StubOffset; + uint8_t *StubTargetAddr = + createStubFunction(Section.Address + Section.StubOffset); + RelocationEntry StubRE(RE.SectionID, StubTargetAddr - Section.Address, + MachO::GENERIC_RELOC_VANILLA, Value.Addend); + if (Value.SymbolName) + addRelocationForSymbol(StubRE, Value.SymbolName); + else + addRelocationForSection(StubRE, Value.SectionID); + Addr = Section.Address + Section.StubOffset; + Section.StubOffset += getMaxStubSize(); + } + RelocationEntry TargetRE(Value.SectionID, RE.Offset, RE.RelType, 0, + RE.IsPCRel, RE.Size); + resolveRelocation(TargetRE, (uint64_t)Addr); + } +}; +} + +#undef DEBUG_TYPE + +#endif // LLVM_RUNTIMEDYLDMACHOARM_H |