llvm-6502/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOX86_64.h
Lang Hames f0ad482410 [MCJIT] Rewrite RuntimeDyldMachO and its derived classes to use the 'Offset'
field of RelocationValueRef, rather than the 'Addend' field.

This is consistent with RuntimeDyldELF's use of RelocationValueRef, and more
consistent with the semantics of the data being stored (the offset from the
start of a section or symbol).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217328 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-07 04:03:32 +00:00

137 lines
4.6 KiB
C++

//===-- RuntimeDyldMachOX86_64.h ---- MachO/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.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_EXECUTIONENGINE_RUNTIMEDYLD_TARGETS_RUNTIMEDYLDMACHOX86_64_H
#define LLVM_LIB_EXECUTIONENGINE_RUNTIMEDYLD_TARGETS_RUNTIMEDYLDMACHOX86_64_H
#include "../RuntimeDyldMachO.h"
#define DEBUG_TYPE "dyld"
namespace llvm {
class RuntimeDyldMachOX86_64
: public RuntimeDyldMachOCRTPBase<RuntimeDyldMachOX86_64> {
public:
typedef uint64_t TargetPtrT;
RuntimeDyldMachOX86_64(RTDyldMemoryManager *MM)
: RuntimeDyldMachOCRTPBase(MM) {}
unsigned getMaxStubSize() override { return 8; }
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());
assert(!Obj.isRelocationScattered(RelInfo) &&
"Scattered relocations not supported on X86_64");
RelocationEntry RE(getRelocationEntry(SectionID, ObjImg, RelI));
RE.Addend = memcpyAddend(RE);
RelocationValueRef Value(
getRelocationValueRef(ObjImg, RelI, RE, ObjSectionToID, Symbols));
bool IsExtern = Obj.getPlainRelocationExternal(RelInfo);
if (!IsExtern && RE.IsPCRel)
makeValueAddendPCRel(Value, ObjImg, RelI, 1 << RE.Size);
if (RE.RelType == MachO::X86_64_RELOC_GOT ||
RE.RelType == MachO::X86_64_RELOC_GOT_LOAD)
processGOTRelocation(RE, Value, Stubs);
else {
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 the relocation is PC-relative, the value to be encoded is the
// pointer difference.
if (RE.IsPCRel) {
// FIXME: It seems this value needs to be adjusted by 4 for an effective
// PC address. Is that expected? Only for branches, perhaps?
uint64_t FinalAddress = Section.LoadAddress + RE.Offset;
Value -= FinalAddress + 4;
}
switch (RE.RelType) {
default:
llvm_unreachable("Invalid relocation type!");
case MachO::X86_64_RELOC_SIGNED_1:
case MachO::X86_64_RELOC_SIGNED_2:
case MachO::X86_64_RELOC_SIGNED_4:
case MachO::X86_64_RELOC_SIGNED:
case MachO::X86_64_RELOC_UNSIGNED:
case MachO::X86_64_RELOC_BRANCH:
writeBytesUnaligned(Value + RE.Addend, LocalAddress, 1 << RE.Size);
break;
case MachO::X86_64_RELOC_GOT_LOAD:
case MachO::X86_64_RELOC_GOT:
case MachO::X86_64_RELOC_SUBTRACTOR:
case MachO::X86_64_RELOC_TLV:
Error("Relocation type not implemented yet!");
}
}
void finalizeSection(ObjectImage &ObjImg, unsigned SectionID,
const SectionRef &Section) {}
private:
void processGOTRelocation(const RelocationEntry &RE,
RelocationValueRef &Value, StubMap &Stubs) {
SectionEntry &Section = Sections[RE.SectionID];
assert(RE.IsPCRel);
assert(RE.Size == 2);
Value.Offset -= RE.Addend;
RuntimeDyldMachO::StubMap::const_iterator i = Stubs.find(Value);
uint8_t *Addr;
if (i != Stubs.end()) {
Addr = Section.Address + i->second;
} else {
Stubs[Value] = Section.StubOffset;
uint8_t *GOTEntry = Section.Address + Section.StubOffset;
RelocationEntry GOTRE(RE.SectionID, Section.StubOffset,
MachO::X86_64_RELOC_UNSIGNED, Value.Offset, false,
3);
if (Value.SymbolName)
addRelocationForSymbol(GOTRE, Value.SymbolName);
else
addRelocationForSection(GOTRE, Value.SectionID);
Section.StubOffset += 8;
Addr = GOTEntry;
}
RelocationEntry TargetRE(RE.SectionID, RE.Offset,
MachO::X86_64_RELOC_UNSIGNED, RE.Addend, true, 2);
resolveRelocation(TargetRE, (uint64_t)Addr);
}
};
}
#undef DEBUG_TYPE
#endif