namespace llvm {
+static unsigned char *processFDE(unsigned char *P, intptr_t DeltaForText, intptr_t DeltaForEH) {
+ uint32_t Length = *((uint32_t*)P);
+ P += 4;
+ unsigned char *Ret = P + Length;
+ uint32_t Offset = *((uint32_t*)P);
+ if (Offset == 0) // is a CIE
+ return Ret;
+
+ P += 4;
+ intptr_t FDELocation = *((intptr_t*)P);
+ intptr_t NewLocation = FDELocation - DeltaForText;
+ *((intptr_t*)P) = NewLocation;
+ P += sizeof(intptr_t);
+
+ // Skip the FDE address range
+ P += sizeof(intptr_t);
+
+ uint8_t Augmentationsize = *P;
+ P += 1;
+ if (Augmentationsize != 0) {
+ intptr_t LSDA = *((intptr_t*)P);
+ intptr_t NewLSDA = LSDA - DeltaForEH;
+ *((intptr_t*)P) = NewLSDA;
+ }
+
+ return Ret;
+}
+
+static intptr_t computeDelta(SectionEntry *A, SectionEntry *B) {
+ intptr_t ObjDistance = A->ObjAddress - B->ObjAddress;
+ intptr_t MemDistance = A->LoadAddress - B->LoadAddress;
+ return ObjDistance - MemDistance;
+}
+
+StringRef RuntimeDyldMachO::getEHFrameSection() {
+ SectionEntry *Text = NULL;
+ SectionEntry *EHFrame = NULL;
+ SectionEntry *ExceptTab = NULL;
+ for (int i = 0, e = Sections.size(); i != e; ++i) {
+ if (Sections[i].Name == "__eh_frame")
+ EHFrame = &Sections[i];
+ else if (Sections[i].Name == "__text")
+ Text = &Sections[i];
+ else if (Sections[i].Name == "__gcc_except_tab")
+ ExceptTab = &Sections[i];
+ }
+ if (Text == NULL || EHFrame == NULL)
+ return StringRef();
+
+ intptr_t DeltaForText = computeDelta(Text, EHFrame);
+ intptr_t DeltaForEH = 0;
+ if (ExceptTab)
+ DeltaForEH = computeDelta(ExceptTab, EHFrame);
+
+ unsigned char *P = EHFrame->Address;
+ unsigned char *End = P + EHFrame->Size;
+ do {
+ P = processFDE(P, DeltaForText, DeltaForEH);
+ } while(P != End);
+
+ return StringRef((char*)EHFrame->Address, EHFrame->Size);
+}
+
+// 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 RuntimeDyldMachO::resolveRelocation(const RelocationEntry &RE,
+ uint64_t Value) {
+ const SectionEntry &Section = Sections[RE.SectionID];
+ return resolveRelocation(Section, RE.Offset, Value, RE.RelType, RE.Addend,
+ RE.IsPCRel, RE.Size);
+}
+
void RuntimeDyldMachO::resolveRelocation(const SectionEntry &Section,
uint64_t Offset,
uint64_t Value,
uint32_t Type,
- int64_t Addend) {
+ int64_t Addend,
+ bool isPCRel,
+ unsigned LogSize) {
uint8_t *LocalAddress = Section.Address + Offset;
uint64_t FinalAddress = Section.LoadAddress + Offset;
- bool isPCRel = (Type >> 24) & 1;
- unsigned MachoType = (Type >> 28) & 0xf;
- unsigned Size = 1 << ((Type >> 25) & 3);
+ unsigned MachoType = Type;
+ unsigned Size = 1 << LogSize;
DEBUG(dbgs() << "resolveRelocation LocalAddress: "
<< format("%p", LocalAddress)
switch (Type) {
default:
llvm_unreachable("Invalid relocation type!");
- case macho::RIT_Vanilla: {
+ case MachO::GENERIC_RELOC_VANILLA: {
uint8_t *p = LocalAddress;
uint64_t ValueToWrite = Value + Addend;
for (unsigned i = 0; i < Size; ++i) {
}
return false;
}
- case macho::RIT_Difference:
- case macho::RIT_Generic_LocalDifference:
- case macho::RIT_Generic_PreboundLazyPointer:
+ case MachO::GENERIC_RELOC_SECTDIFF:
+ case MachO::GENERIC_RELOC_LOCAL_SECTDIFF:
+ case MachO::GENERIC_RELOC_PB_LA_PTR:
return Error("Relocation type not implemented yet!");
}
}
switch(Type) {
default:
llvm_unreachable("Invalid relocation type!");
- case macho::RIT_X86_64_Signed1:
- case macho::RIT_X86_64_Signed2:
- case macho::RIT_X86_64_Signed4:
- case macho::RIT_X86_64_Signed:
- case macho::RIT_X86_64_Unsigned:
- case macho::RIT_X86_64_Branch: {
+ 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: {
Value += Addend;
// Mask in the target value a byte at a time (we don't have an alignment
// guarantee for the target address, so this is safest).
}
return false;
}
- case macho::RIT_X86_64_GOTLoad:
- case macho::RIT_X86_64_GOT:
- case macho::RIT_X86_64_Subtractor:
- case macho::RIT_X86_64_TLV:
+ 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:
return Error("Relocation type not implemented yet!");
}
}
switch(Type) {
default:
llvm_unreachable("Invalid relocation type!");
- case macho::RIT_Vanilla: {
+ case MachO::ARM_RELOC_VANILLA: {
// Mask in the target value a byte at a time (we don't have an alignment
// guarantee for the target address, so this is safest).
uint8_t *p = (uint8_t*)LocalAddress;
}
break;
}
- case macho::RIT_ARM_Branch24Bit: {
+ 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;
*p = (*p & ~0xffffff) | Value;
break;
}
- case macho::RIT_ARM_ThumbBranch22Bit:
- case macho::RIT_ARM_ThumbBranch32Bit:
- case macho::RIT_ARM_Half:
- case macho::RIT_ARM_HalfDifference:
- case macho::RIT_Pair:
- case macho::RIT_Difference:
- case macho::RIT_ARM_LocalDifference:
- case macho::RIT_ARM_PreboundLazyPointer:
+ 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:
return Error("Relocation type not implemented yet!");
}
return false;
}
void RuntimeDyldMachO::processRelocationRef(unsigned SectionID,
- relocation_iterator RelI,
+ RelocationRef RelI,
ObjectImage &Obj,
ObjSectionToIDMap &ObjSectionToID,
const SymbolTableMap &Symbols,
StubMap &Stubs) {
const ObjectFile *OF = Obj.getObjectFile();
const MachOObjectFile *MachO = static_cast<const MachOObjectFile*>(OF);
- macho::RelocationEntry RE = MachO->getRelocation(RelI->getRawDataRefImpl());
+ MachO::any_relocation_info RE= MachO->getRelocation(RelI.getRawDataRefImpl());
uint32_t RelType = MachO->getAnyRelocationType(RE);
+
+ // FIXME: Properly handle scattered relocations.
+ // For now, optimistically skip these: they can often be ignored, as
+ // the static linker will already have applied the relocation, and it
+ // only needs to be reapplied if symbols move relative to one another.
+ // Note: This will fail horribly where the relocations *do* need to be
+ // applied, but that was already the case.
+ if (MachO->isRelocationScattered(RE))
+ return;
+
RelocationValueRef Value;
SectionEntry &Section = Sections[SectionID];
bool isExtern = MachO->getPlainRelocationExternal(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 = 0;
+ memcpy(&Addend, LocalAddress, NumBytes);
+
if (isExtern) {
// Obtain the symbol name which is referenced in the relocation
- SymbolRef Symbol;
- RelI->getSymbol(Symbol);
+ symbol_iterator Symbol = RelI.getSymbol();
StringRef TargetName;
- Symbol.getName(TargetName);
+ Symbol->getName(TargetName);
// First search for the symbol in the local symbol table
SymbolTableMap::const_iterator lsi = Symbols.find(TargetName.data());
if (lsi != Symbols.end()) {
Value.SectionID = lsi->second.first;
- Value.Addend = lsi->second.second;
+ Value.Addend = lsi->second.second + Addend;
} else {
// Search for the symbol in the global symbol table
SymbolTableMap::const_iterator gsi = GlobalSymbolTable.find(TargetName.data());
if (gsi != GlobalSymbolTable.end()) {
Value.SectionID = gsi->second.first;
- Value.Addend = gsi->second.second;
- } else
+ Value.Addend = gsi->second.second + Addend;
+ } else {
Value.SymbolName = TargetName.data();
+ Value.Addend = Addend;
+ }
}
} else {
- error_code err;
- uint8_t sectionIndex = static_cast<uint8_t>(RelType & 0xFF);
- section_iterator si = Obj.begin_sections(),
- se = Obj.end_sections();
- for (uint8_t i = 1; i < sectionIndex; i++) {
- error_code err;
- si.increment(err);
- if (si == se)
- break;
- }
- assert(si != se && "No section containing relocation!");
- Value.SectionID = findOrEmitSection(Obj, *si, true, ObjSectionToID);
- Value.Addend = 0;
- // FIXME: The size and type of the relocation determines if we can
- // encode an Addend in the target location itself, and if so, how many
- // bytes we should read in order to get it. We don't yet support doing
- // that, and just assuming it's sizeof(intptr_t) is blatantly wrong.
- //Value.Addend = *(const intptr_t *)Target;
- if (Value.Addend) {
- // The MachO addend is an offset from the current section. We need it
- // to be an offset from the destination section
- Value.Addend += Section.ObjAddress - Sections[Value.SectionID].ObjAddress;
- }
+ SectionRef Sec = MachO->getRelocationSection(RE);
+ Value.SectionID = findOrEmitSection(Obj, Sec, true, ObjSectionToID);
+ uint64_t Addr;
+ Sec.getAddress(Addr);
+ Value.Addend = Addend - Addr;
}
- uint64_t Offset;
- RelI->getOffset(Offset);
- if (Arch == Triple::arm && (RelType & 0xf) == macho::RIT_ARM_Branch24Bit) {
+ if (Arch == Triple::x86_64 && (RelType == MachO::X86_64_RELOC_GOT ||
+ RelType == MachO::X86_64_RELOC_GOT_LOAD)) {
+ assert(IsPCRel);
+ assert(Size == 2);
+ 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 RE(SectionID, Section.StubOffset,
+ MachO::X86_64_RELOC_UNSIGNED, 0, false, 3);
+ if (Value.SymbolName)
+ addRelocationForSymbol(RE, Value.SymbolName);
+ else
+ addRelocationForSection(RE, Value.SectionID);
+ Section.StubOffset += 8;
+ Addr = GOTEntry;
+ }
+ resolveRelocation(Section, Offset, (uint64_t)Addr,
+ MachO::X86_64_RELOC_UNSIGNED, Value.Addend, true, 2);
+ } else if (Arch == Triple::arm &&
+ (RelType & 0xf) == MachO::ARM_RELOC_BR24) {
// This is an ARM branch relocation, need to use a stub function.
// Look up for existing stub.
if (i != Stubs.end())
resolveRelocation(Section, Offset,
(uint64_t)Section.Address + i->second,
- RelType, 0);
+ RelType, 0, IsPCRel, Size);
else {
// Create a new stub function.
Stubs[Value] = Section.StubOffset;
uint8_t *StubTargetAddr = createStubFunction(Section.Address +
Section.StubOffset);
RelocationEntry RE(SectionID, StubTargetAddr - Section.Address,
- macho::RIT_Vanilla, Value.Addend);
+ MachO::GENERIC_RELOC_VANILLA, Value.Addend);
if (Value.SymbolName)
addRelocationForSymbol(RE, Value.SymbolName);
else
addRelocationForSection(RE, Value.SectionID);
resolveRelocation(Section, Offset,
(uint64_t)Section.Address + Section.StubOffset,
- RelType, 0);
+ RelType, 0, IsPCRel, Size);
Section.StubOffset += getMaxStubSize();
}
} else {
- RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
+ RelocationEntry RE(SectionID, Offset, RelType, Value.Addend,
+ IsPCRel, Size);
if (Value.SymbolName)
addRelocationForSymbol(RE, Value.SymbolName);
else