llvm-project/llvm/lib/Object/MachOObjectFile.cpp

1337 lines
42 KiB
C++

//===- MachOObjectFile.cpp - Mach-O object file binding ---------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the MachOObjectFile class, which binds the MachOObject
// class to the generic ObjectFile wrapper.
//
//===----------------------------------------------------------------------===//
#include "llvm/Object/MachO.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Object/MachOFormat.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/MemoryBuffer.h"
#include <cctype>
#include <cstring>
#include <limits>
using namespace llvm;
using namespace object;
namespace llvm {
namespace object {
MachOObjectFile::MachOObjectFile(MemoryBuffer *Object, MachOObject *MOO,
error_code &ec)
: ObjectFile(Binary::ID_MachO, Object, ec),
MachOObj(MOO),
RegisteredStringTable(std::numeric_limits<uint32_t>::max()) {
DataRefImpl DRI;
moveToNextSection(DRI);
uint32_t LoadCommandCount = MachOObj->getHeader().NumLoadCommands;
while (DRI.d.a < LoadCommandCount) {
Sections.push_back(DRI);
DRI.d.b++;
moveToNextSection(DRI);
}
}
ObjectFile *ObjectFile::createMachOObjectFile(MemoryBuffer *Buffer) {
error_code ec;
std::string Err;
MachOObject *MachOObj = MachOObject::LoadFromBuffer(Buffer, &Err);
if (!MachOObj)
return NULL;
// MachOObject takes ownership of the Buffer we passed to it, and
// MachOObjectFile does, too, so we need to make sure they don't get the
// same object. A MemoryBuffer is cheap (it's just a reference to memory,
// not a copy of the memory itself), so just make a new copy here for
// the MachOObjectFile.
MemoryBuffer *NewBuffer =
MemoryBuffer::getMemBuffer(Buffer->getBuffer(),
Buffer->getBufferIdentifier(), false);
return new MachOObjectFile(NewBuffer, MachOObj, ec);
}
/*===-- Symbols -----------------------------------------------------------===*/
void MachOObjectFile::moveToNextSymbol(DataRefImpl &DRI) const {
uint32_t LoadCommandCount = MachOObj->getHeader().NumLoadCommands;
while (DRI.d.a < LoadCommandCount) {
LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
if (LCI.Command.Type == macho::LCT_Symtab) {
InMemoryStruct<macho::SymtabLoadCommand> SymtabLoadCmd;
MachOObj->ReadSymtabLoadCommand(LCI, SymtabLoadCmd);
if (DRI.d.b < SymtabLoadCmd->NumSymbolTableEntries)
return;
}
DRI.d.a++;
DRI.d.b = 0;
}
}
void MachOObjectFile::getSymbolTableEntry(DataRefImpl DRI,
InMemoryStruct<macho::SymbolTableEntry> &Res) const {
InMemoryStruct<macho::SymtabLoadCommand> SymtabLoadCmd;
LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
MachOObj->ReadSymtabLoadCommand(LCI, SymtabLoadCmd);
if (RegisteredStringTable != DRI.d.a) {
MachOObj->RegisterStringTable(*SymtabLoadCmd);
RegisteredStringTable = DRI.d.a;
}
MachOObj->ReadSymbolTableEntry(SymtabLoadCmd->SymbolTableOffset, DRI.d.b,
Res);
}
void MachOObjectFile::getSymbol64TableEntry(DataRefImpl DRI,
InMemoryStruct<macho::Symbol64TableEntry> &Res) const {
InMemoryStruct<macho::SymtabLoadCommand> SymtabLoadCmd;
LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
MachOObj->ReadSymtabLoadCommand(LCI, SymtabLoadCmd);
if (RegisteredStringTable != DRI.d.a) {
MachOObj->RegisterStringTable(*SymtabLoadCmd);
RegisteredStringTable = DRI.d.a;
}
MachOObj->ReadSymbol64TableEntry(SymtabLoadCmd->SymbolTableOffset, DRI.d.b,
Res);
}
error_code MachOObjectFile::getSymbolNext(DataRefImpl DRI,
SymbolRef &Result) const {
DRI.d.b++;
moveToNextSymbol(DRI);
Result = SymbolRef(DRI, this);
return object_error::success;
}
error_code MachOObjectFile::getSymbolName(DataRefImpl DRI,
StringRef &Result) const {
if (MachOObj->is64Bit()) {
InMemoryStruct<macho::Symbol64TableEntry> Entry;
getSymbol64TableEntry(DRI, Entry);
Result = MachOObj->getStringAtIndex(Entry->StringIndex);
} else {
InMemoryStruct<macho::SymbolTableEntry> Entry;
getSymbolTableEntry(DRI, Entry);
Result = MachOObj->getStringAtIndex(Entry->StringIndex);
}
return object_error::success;
}
error_code MachOObjectFile::getSymbolFileOffset(DataRefImpl DRI,
uint64_t &Result) const {
if (MachOObj->is64Bit()) {
InMemoryStruct<macho::Symbol64TableEntry> Entry;
getSymbol64TableEntry(DRI, Entry);
Result = Entry->Value;
if (Entry->SectionIndex) {
InMemoryStruct<macho::Section64> Section;
getSection64(Sections[Entry->SectionIndex-1], Section);
Result += Section->Offset - Section->Address;
}
} else {
InMemoryStruct<macho::SymbolTableEntry> Entry;
getSymbolTableEntry(DRI, Entry);
Result = Entry->Value;
if (Entry->SectionIndex) {
InMemoryStruct<macho::Section> Section;
getSection(Sections[Entry->SectionIndex-1], Section);
Result += Section->Offset - Section->Address;
}
}
return object_error::success;
}
error_code MachOObjectFile::getSymbolAddress(DataRefImpl DRI,
uint64_t &Result) const {
if (MachOObj->is64Bit()) {
InMemoryStruct<macho::Symbol64TableEntry> Entry;
getSymbol64TableEntry(DRI, Entry);
Result = Entry->Value;
} else {
InMemoryStruct<macho::SymbolTableEntry> Entry;
getSymbolTableEntry(DRI, Entry);
Result = Entry->Value;
}
return object_error::success;
}
error_code MachOObjectFile::getSymbolSize(DataRefImpl DRI,
uint64_t &Result) const {
uint32_t LoadCommandCount = MachOObj->getHeader().NumLoadCommands;
uint64_t BeginOffset;
uint64_t EndOffset = 0;
uint8_t SectionIndex;
if (MachOObj->is64Bit()) {
InMemoryStruct<macho::Symbol64TableEntry> Entry;
getSymbol64TableEntry(DRI, Entry);
BeginOffset = Entry->Value;
SectionIndex = Entry->SectionIndex;
if (!SectionIndex) {
uint32_t flags = SymbolRef::SF_None;
getSymbolFlags(DRI, flags);
if (flags & SymbolRef::SF_Common)
Result = Entry->Value;
else
Result = UnknownAddressOrSize;
return object_error::success;
}
// Unfortunately symbols are unsorted so we need to touch all
// symbols from load command
DRI.d.b = 0;
uint32_t Command = DRI.d.a;
while (Command == DRI.d.a) {
moveToNextSymbol(DRI);
if (DRI.d.a < LoadCommandCount) {
getSymbol64TableEntry(DRI, Entry);
if (Entry->SectionIndex == SectionIndex && Entry->Value > BeginOffset)
if (!EndOffset || Entry->Value < EndOffset)
EndOffset = Entry->Value;
}
DRI.d.b++;
}
} else {
InMemoryStruct<macho::SymbolTableEntry> Entry;
getSymbolTableEntry(DRI, Entry);
BeginOffset = Entry->Value;
SectionIndex = Entry->SectionIndex;
if (!SectionIndex) {
uint32_t flags = SymbolRef::SF_None;
getSymbolFlags(DRI, flags);
if (flags & SymbolRef::SF_Common)
Result = Entry->Value;
else
Result = UnknownAddressOrSize;
return object_error::success;
}
// Unfortunately symbols are unsorted so we need to touch all
// symbols from load command
DRI.d.b = 0;
uint32_t Command = DRI.d.a;
while (Command == DRI.d.a) {
moveToNextSymbol(DRI);
if (DRI.d.a < LoadCommandCount) {
getSymbolTableEntry(DRI, Entry);
if (Entry->SectionIndex == SectionIndex && Entry->Value > BeginOffset)
if (!EndOffset || Entry->Value < EndOffset)
EndOffset = Entry->Value;
}
DRI.d.b++;
}
}
if (!EndOffset) {
uint64_t Size;
getSectionSize(Sections[SectionIndex-1], Size);
getSectionAddress(Sections[SectionIndex-1], EndOffset);
EndOffset += Size;
}
Result = EndOffset - BeginOffset;
return object_error::success;
}
error_code MachOObjectFile::getSymbolNMTypeChar(DataRefImpl DRI,
char &Result) const {
uint8_t Type, Flags;
if (MachOObj->is64Bit()) {
InMemoryStruct<macho::Symbol64TableEntry> Entry;
getSymbol64TableEntry(DRI, Entry);
Type = Entry->Type;
Flags = Entry->Flags;
} else {
InMemoryStruct<macho::SymbolTableEntry> Entry;
getSymbolTableEntry(DRI, Entry);
Type = Entry->Type;
Flags = Entry->Flags;
}
char Char;
switch (Type & macho::STF_TypeMask) {
case macho::STT_Undefined:
Char = 'u';
break;
case macho::STT_Absolute:
case macho::STT_Section:
Char = 's';
break;
default:
Char = '?';
break;
}
if (Flags & (macho::STF_External | macho::STF_PrivateExtern))
Char = toupper(Char);
Result = Char;
return object_error::success;
}
error_code MachOObjectFile::getSymbolFlags(DataRefImpl DRI,
uint32_t &Result) const {
uint16_t MachOFlags;
uint8_t MachOType;
if (MachOObj->is64Bit()) {
InMemoryStruct<macho::Symbol64TableEntry> Entry;
getSymbol64TableEntry(DRI, Entry);
MachOFlags = Entry->Flags;
MachOType = Entry->Type;
} else {
InMemoryStruct<macho::SymbolTableEntry> Entry;
getSymbolTableEntry(DRI, Entry);
MachOFlags = Entry->Flags;
MachOType = Entry->Type;
}
// TODO: Correctly set SF_ThreadLocal
Result = SymbolRef::SF_None;
if ((MachOType & MachO::NlistMaskType) == MachO::NListTypeUndefined)
Result |= SymbolRef::SF_Undefined;
if (MachOFlags & macho::STF_StabsEntryMask)
Result |= SymbolRef::SF_FormatSpecific;
if (MachOType & MachO::NlistMaskExternal) {
Result |= SymbolRef::SF_Global;
if ((MachOType & MachO::NlistMaskType) == MachO::NListTypeUndefined)
Result |= SymbolRef::SF_Common;
}
if (MachOFlags & (MachO::NListDescWeakRef | MachO::NListDescWeakDef))
Result |= SymbolRef::SF_Weak;
if ((MachOType & MachO::NlistMaskType) == MachO::NListTypeAbsolute)
Result |= SymbolRef::SF_Absolute;
return object_error::success;
}
error_code MachOObjectFile::getSymbolSection(DataRefImpl Symb,
section_iterator &Res) const {
uint8_t index;
if (MachOObj->is64Bit()) {
InMemoryStruct<macho::Symbol64TableEntry> Entry;
getSymbol64TableEntry(Symb, Entry);
index = Entry->SectionIndex;
} else {
InMemoryStruct<macho::SymbolTableEntry> Entry;
getSymbolTableEntry(Symb, Entry);
index = Entry->SectionIndex;
}
if (index == 0)
Res = end_sections();
else
Res = section_iterator(SectionRef(Sections[index-1], this));
return object_error::success;
}
error_code MachOObjectFile::getSymbolType(DataRefImpl Symb,
SymbolRef::Type &Res) const {
uint8_t n_type;
if (MachOObj->is64Bit()) {
InMemoryStruct<macho::Symbol64TableEntry> Entry;
getSymbol64TableEntry(Symb, Entry);
n_type = Entry->Type;
} else {
InMemoryStruct<macho::SymbolTableEntry> Entry;
getSymbolTableEntry(Symb, Entry);
n_type = Entry->Type;
}
Res = SymbolRef::ST_Other;
// If this is a STAB debugging symbol, we can do nothing more.
if (n_type & MachO::NlistMaskStab) {
Res = SymbolRef::ST_Debug;
return object_error::success;
}
switch (n_type & MachO::NlistMaskType) {
case MachO::NListTypeUndefined :
Res = SymbolRef::ST_Unknown;
break;
case MachO::NListTypeSection :
Res = SymbolRef::ST_Function;
break;
}
return object_error::success;
}
error_code MachOObjectFile::getSymbolValue(DataRefImpl Symb,
uint64_t &Val) const {
report_fatal_error("getSymbolValue unimplemented in MachOObjectFile");
}
symbol_iterator MachOObjectFile::begin_symbols() const {
// DRI.d.a = segment number; DRI.d.b = symbol index.
DataRefImpl DRI;
moveToNextSymbol(DRI);
return symbol_iterator(SymbolRef(DRI, this));
}
symbol_iterator MachOObjectFile::end_symbols() const {
DataRefImpl DRI;
DRI.d.a = MachOObj->getHeader().NumLoadCommands;
return symbol_iterator(SymbolRef(DRI, this));
}
symbol_iterator MachOObjectFile::begin_dynamic_symbols() const {
// TODO: implement
report_fatal_error("Dynamic symbols unimplemented in MachOObjectFile");
}
symbol_iterator MachOObjectFile::end_dynamic_symbols() const {
// TODO: implement
report_fatal_error("Dynamic symbols unimplemented in MachOObjectFile");
}
library_iterator MachOObjectFile::begin_libraries_needed() const {
// TODO: implement
report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
}
library_iterator MachOObjectFile::end_libraries_needed() const {
// TODO: implement
report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
}
StringRef MachOObjectFile::getLoadName() const {
// TODO: Implement
report_fatal_error("get_load_name() unimplemented in MachOObjectFile");
}
/*===-- Sections ----------------------------------------------------------===*/
void MachOObjectFile::moveToNextSection(DataRefImpl &DRI) const {
uint32_t LoadCommandCount = MachOObj->getHeader().NumLoadCommands;
while (DRI.d.a < LoadCommandCount) {
LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
if (LCI.Command.Type == macho::LCT_Segment) {
InMemoryStruct<macho::SegmentLoadCommand> SegmentLoadCmd;
MachOObj->ReadSegmentLoadCommand(LCI, SegmentLoadCmd);
if (DRI.d.b < SegmentLoadCmd->NumSections)
return;
} else if (LCI.Command.Type == macho::LCT_Segment64) {
InMemoryStruct<macho::Segment64LoadCommand> Segment64LoadCmd;
MachOObj->ReadSegment64LoadCommand(LCI, Segment64LoadCmd);
if (DRI.d.b < Segment64LoadCmd->NumSections)
return;
}
DRI.d.a++;
DRI.d.b = 0;
}
}
error_code MachOObjectFile::getSectionNext(DataRefImpl DRI,
SectionRef &Result) const {
DRI.d.b++;
moveToNextSection(DRI);
Result = SectionRef(DRI, this);
return object_error::success;
}
void
MachOObjectFile::getSection(DataRefImpl DRI,
InMemoryStruct<macho::Section> &Res) const {
LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
MachOObj->ReadSection(LCI, DRI.d.b, Res);
}
std::size_t MachOObjectFile::getSectionIndex(DataRefImpl Sec) const {
SectionList::const_iterator loc =
std::find(Sections.begin(), Sections.end(), Sec);
assert(loc != Sections.end() && "Sec is not a valid section!");
return std::distance(Sections.begin(), loc);
}
void
MachOObjectFile::getSection64(DataRefImpl DRI,
InMemoryStruct<macho::Section64> &Res) const {
LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
MachOObj->ReadSection64(LCI, DRI.d.b, Res);
}
static bool is64BitLoadCommand(const MachOObject *MachOObj, DataRefImpl DRI) {
LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
if (LCI.Command.Type == macho::LCT_Segment64)
return true;
assert(LCI.Command.Type == macho::LCT_Segment && "Unexpected Type.");
return false;
}
static StringRef parseSegmentOrSectionName(const char *P) {
if (P[15] == 0)
// Null terminated.
return P;
// Not null terminated, so this is a 16 char string.
return StringRef(P, 16);
}
error_code MachOObjectFile::getSectionName(DataRefImpl DRI,
StringRef &Result) const {
if (is64BitLoadCommand(MachOObj.get(), DRI)) {
LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
unsigned SectionOffset = LCI.Offset + sizeof(macho::Segment64LoadCommand) +
DRI.d.b * sizeof(macho::Section64);
StringRef Data = MachOObj->getData(SectionOffset, sizeof(macho::Section64));
const macho::Section64 *sec =
reinterpret_cast<const macho::Section64*>(Data.data());
Result = parseSegmentOrSectionName(sec->Name);
} else {
LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
unsigned SectionOffset = LCI.Offset + sizeof(macho::SegmentLoadCommand) +
DRI.d.b * sizeof(macho::Section);
StringRef Data = MachOObj->getData(SectionOffset, sizeof(macho::Section));
const macho::Section *sec =
reinterpret_cast<const macho::Section*>(Data.data());
Result = parseSegmentOrSectionName(sec->Name);
}
return object_error::success;
}
error_code MachOObjectFile::getSectionFinalSegmentName(DataRefImpl Sec,
StringRef &Res) const {
if (is64BitLoadCommand(MachOObj.get(), Sec)) {
LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(Sec.d.a);
unsigned SectionOffset = LCI.Offset + sizeof(macho::Segment64LoadCommand) +
Sec.d.b * sizeof(macho::Section64);
StringRef Data = MachOObj->getData(SectionOffset, sizeof(macho::Section64));
const macho::Section64 *sec =
reinterpret_cast<const macho::Section64*>(Data.data());
Res = parseSegmentOrSectionName(sec->SegmentName);
} else {
LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(Sec.d.a);
unsigned SectionOffset = LCI.Offset + sizeof(macho::SegmentLoadCommand) +
Sec.d.b * sizeof(macho::Section);
StringRef Data = MachOObj->getData(SectionOffset, sizeof(macho::Section));
const macho::Section *sec =
reinterpret_cast<const macho::Section*>(Data.data());
Res = parseSegmentOrSectionName(sec->SegmentName);
}
return object_error::success;
}
error_code MachOObjectFile::getSectionAddress(DataRefImpl DRI,
uint64_t &Result) const {
if (is64BitLoadCommand(MachOObj.get(), DRI)) {
InMemoryStruct<macho::Section64> Sect;
getSection64(DRI, Sect);
Result = Sect->Address;
} else {
InMemoryStruct<macho::Section> Sect;
getSection(DRI, Sect);
Result = Sect->Address;
}
return object_error::success;
}
error_code MachOObjectFile::getSectionSize(DataRefImpl DRI,
uint64_t &Result) const {
if (is64BitLoadCommand(MachOObj.get(), DRI)) {
InMemoryStruct<macho::Section64> Sect;
getSection64(DRI, Sect);
Result = Sect->Size;
} else {
InMemoryStruct<macho::Section> Sect;
getSection(DRI, Sect);
Result = Sect->Size;
}
return object_error::success;
}
error_code MachOObjectFile::getSectionContents(DataRefImpl DRI,
StringRef &Result) const {
if (is64BitLoadCommand(MachOObj.get(), DRI)) {
InMemoryStruct<macho::Section64> Sect;
getSection64(DRI, Sect);
Result = MachOObj->getData(Sect->Offset, Sect->Size);
} else {
InMemoryStruct<macho::Section> Sect;
getSection(DRI, Sect);
Result = MachOObj->getData(Sect->Offset, Sect->Size);
}
return object_error::success;
}
error_code MachOObjectFile::getSectionAlignment(DataRefImpl DRI,
uint64_t &Result) const {
if (is64BitLoadCommand(MachOObj.get(), DRI)) {
InMemoryStruct<macho::Section64> Sect;
getSection64(DRI, Sect);
Result = uint64_t(1) << Sect->Align;
} else {
InMemoryStruct<macho::Section> Sect;
getSection(DRI, Sect);
Result = uint64_t(1) << Sect->Align;
}
return object_error::success;
}
error_code MachOObjectFile::isSectionText(DataRefImpl DRI,
bool &Result) const {
if (is64BitLoadCommand(MachOObj.get(), DRI)) {
InMemoryStruct<macho::Section64> Sect;
getSection64(DRI, Sect);
Result = Sect->Flags & macho::SF_PureInstructions;
} else {
InMemoryStruct<macho::Section> Sect;
getSection(DRI, Sect);
Result = Sect->Flags & macho::SF_PureInstructions;
}
return object_error::success;
}
error_code MachOObjectFile::isSectionData(DataRefImpl DRI,
bool &Result) const {
// FIXME: Unimplemented.
Result = false;
return object_error::success;
}
error_code MachOObjectFile::isSectionBSS(DataRefImpl DRI,
bool &Result) const {
// FIXME: Unimplemented.
Result = false;
return object_error::success;
}
error_code MachOObjectFile::isSectionRequiredForExecution(DataRefImpl Sec,
bool &Result) const {
// FIXME: Unimplemented.
Result = true;
return object_error::success;
}
error_code MachOObjectFile::isSectionVirtual(DataRefImpl Sec,
bool &Result) const {
// FIXME: Unimplemented.
Result = false;
return object_error::success;
}
error_code MachOObjectFile::isSectionZeroInit(DataRefImpl DRI,
bool &Result) const {
if (MachOObj->is64Bit()) {
InMemoryStruct<macho::Section64> Sect;
getSection64(DRI, Sect);
unsigned SectionType = Sect->Flags & MachO::SectionFlagMaskSectionType;
Result = (SectionType == MachO::SectionTypeZeroFill ||
SectionType == MachO::SectionTypeZeroFillLarge);
} else {
InMemoryStruct<macho::Section> Sect;
getSection(DRI, Sect);
unsigned SectionType = Sect->Flags & MachO::SectionFlagMaskSectionType;
Result = (SectionType == MachO::SectionTypeZeroFill ||
SectionType == MachO::SectionTypeZeroFillLarge);
}
return object_error::success;
}
error_code MachOObjectFile::isSectionReadOnlyData(DataRefImpl Sec,
bool &Result) const {
// Consider using the code from isSectionText to look for __const sections.
// Alternately, emit S_ATTR_PURE_INSTRUCTIONS and/or S_ATTR_SOME_INSTRUCTIONS
// to use section attributes to distinguish code from data.
// FIXME: Unimplemented.
Result = false;
return object_error::success;
}
error_code MachOObjectFile::sectionContainsSymbol(DataRefImpl Sec,
DataRefImpl Symb,
bool &Result) const {
SymbolRef::Type ST;
getSymbolType(Symb, ST);
if (ST == SymbolRef::ST_Unknown) {
Result = false;
return object_error::success;
}
uint64_t SectBegin, SectEnd;
getSectionAddress(Sec, SectBegin);
getSectionSize(Sec, SectEnd);
SectEnd += SectBegin;
if (MachOObj->is64Bit()) {
InMemoryStruct<macho::Symbol64TableEntry> Entry;
getSymbol64TableEntry(Symb, Entry);
uint64_t SymAddr= Entry->Value;
Result = (SymAddr >= SectBegin) && (SymAddr < SectEnd);
} else {
InMemoryStruct<macho::SymbolTableEntry> Entry;
getSymbolTableEntry(Symb, Entry);
uint64_t SymAddr= Entry->Value;
Result = (SymAddr >= SectBegin) && (SymAddr < SectEnd);
}
return object_error::success;
}
relocation_iterator MachOObjectFile::getSectionRelBegin(DataRefImpl Sec) const {
DataRefImpl ret;
ret.d.b = getSectionIndex(Sec);
return relocation_iterator(RelocationRef(ret, this));
}
relocation_iterator MachOObjectFile::getSectionRelEnd(DataRefImpl Sec) const {
uint32_t last_reloc;
if (is64BitLoadCommand(MachOObj.get(), Sec)) {
InMemoryStruct<macho::Section64> Sect;
getSection64(Sec, Sect);
last_reloc = Sect->NumRelocationTableEntries;
} else {
InMemoryStruct<macho::Section> Sect;
getSection(Sec, Sect);
last_reloc = Sect->NumRelocationTableEntries;
}
DataRefImpl ret;
ret.d.a = last_reloc;
ret.d.b = getSectionIndex(Sec);
return relocation_iterator(RelocationRef(ret, this));
}
section_iterator MachOObjectFile::begin_sections() const {
DataRefImpl DRI;
moveToNextSection(DRI);
return section_iterator(SectionRef(DRI, this));
}
section_iterator MachOObjectFile::end_sections() const {
DataRefImpl DRI;
DRI.d.a = MachOObj->getHeader().NumLoadCommands;
return section_iterator(SectionRef(DRI, this));
}
/*===-- Relocations -------------------------------------------------------===*/
void MachOObjectFile::
getRelocation(DataRefImpl Rel,
InMemoryStruct<macho::RelocationEntry> &Res) const {
uint32_t relOffset;
if (MachOObj->is64Bit()) {
InMemoryStruct<macho::Section64> Sect;
getSection64(Sections[Rel.d.b], Sect);
relOffset = Sect->RelocationTableOffset;
} else {
InMemoryStruct<macho::Section> Sect;
getSection(Sections[Rel.d.b], Sect);
relOffset = Sect->RelocationTableOffset;
}
MachOObj->ReadRelocationEntry(relOffset, Rel.d.a, Res);
}
error_code MachOObjectFile::getRelocationNext(DataRefImpl Rel,
RelocationRef &Res) const {
++Rel.d.a;
Res = RelocationRef(Rel, this);
return object_error::success;
}
error_code MachOObjectFile::getRelocationAddress(DataRefImpl Rel,
uint64_t &Res) const {
const uint8_t* sectAddress = 0;
if (MachOObj->is64Bit()) {
InMemoryStruct<macho::Section64> Sect;
getSection64(Sections[Rel.d.b], Sect);
sectAddress += Sect->Address;
} else {
InMemoryStruct<macho::Section> Sect;
getSection(Sections[Rel.d.b], Sect);
sectAddress += Sect->Address;
}
InMemoryStruct<macho::RelocationEntry> RE;
getRelocation(Rel, RE);
unsigned Arch = getArch();
bool isScattered = (Arch != Triple::x86_64) &&
(RE->Word0 & macho::RF_Scattered);
uint64_t RelAddr = 0;
if (isScattered)
RelAddr = RE->Word0 & 0xFFFFFF;
else
RelAddr = RE->Word0;
Res = reinterpret_cast<uintptr_t>(sectAddress + RelAddr);
return object_error::success;
}
error_code MachOObjectFile::getRelocationOffset(DataRefImpl Rel,
uint64_t &Res) const {
InMemoryStruct<macho::RelocationEntry> RE;
getRelocation(Rel, RE);
unsigned Arch = getArch();
bool isScattered = (Arch != Triple::x86_64) &&
(RE->Word0 & macho::RF_Scattered);
if (isScattered)
Res = RE->Word0 & 0xFFFFFF;
else
Res = RE->Word0;
return object_error::success;
}
error_code MachOObjectFile::getRelocationSymbol(DataRefImpl Rel,
SymbolRef &Res) const {
InMemoryStruct<macho::RelocationEntry> RE;
getRelocation(Rel, RE);
uint32_t SymbolIdx = RE->Word1 & 0xffffff;
bool isExtern = (RE->Word1 >> 27) & 1;
DataRefImpl Sym;
moveToNextSymbol(Sym);
if (isExtern) {
for (unsigned i = 0; i < SymbolIdx; i++) {
Sym.d.b++;
moveToNextSymbol(Sym);
assert(Sym.d.a < MachOObj->getHeader().NumLoadCommands &&
"Relocation symbol index out of range!");
}
}
Res = SymbolRef(Sym, this);
return object_error::success;
}
error_code MachOObjectFile::getRelocationType(DataRefImpl Rel,
uint64_t &Res) const {
InMemoryStruct<macho::RelocationEntry> RE;
getRelocation(Rel, RE);
Res = RE->Word0;
Res <<= 32;
Res |= RE->Word1;
return object_error::success;
}
error_code MachOObjectFile::getRelocationTypeName(DataRefImpl Rel,
SmallVectorImpl<char> &Result) const {
// TODO: Support scattered relocations.
StringRef res;
InMemoryStruct<macho::RelocationEntry> RE;
getRelocation(Rel, RE);
unsigned Arch = getArch();
bool isScattered = (Arch != Triple::x86_64) &&
(RE->Word0 & macho::RF_Scattered);
unsigned r_type;
if (isScattered)
r_type = (RE->Word0 >> 24) & 0xF;
else
r_type = (RE->Word1 >> 28) & 0xF;
switch (Arch) {
case Triple::x86: {
static const char *const Table[] = {
"GENERIC_RELOC_VANILLA",
"GENERIC_RELOC_PAIR",
"GENERIC_RELOC_SECTDIFF",
"GENERIC_RELOC_PB_LA_PTR",
"GENERIC_RELOC_LOCAL_SECTDIFF",
"GENERIC_RELOC_TLV" };
if (r_type > 6)
res = "Unknown";
else
res = Table[r_type];
break;
}
case Triple::x86_64: {
static const char *const Table[] = {
"X86_64_RELOC_UNSIGNED",
"X86_64_RELOC_SIGNED",
"X86_64_RELOC_BRANCH",
"X86_64_RELOC_GOT_LOAD",
"X86_64_RELOC_GOT",
"X86_64_RELOC_SUBTRACTOR",
"X86_64_RELOC_SIGNED_1",
"X86_64_RELOC_SIGNED_2",
"X86_64_RELOC_SIGNED_4",
"X86_64_RELOC_TLV" };
if (r_type > 9)
res = "Unknown";
else
res = Table[r_type];
break;
}
case Triple::arm: {
static const char *const Table[] = {
"ARM_RELOC_VANILLA",
"ARM_RELOC_PAIR",
"ARM_RELOC_SECTDIFF",
"ARM_RELOC_LOCAL_SECTDIFF",
"ARM_RELOC_PB_LA_PTR",
"ARM_RELOC_BR24",
"ARM_THUMB_RELOC_BR22",
"ARM_THUMB_32BIT_BRANCH",
"ARM_RELOC_HALF",
"ARM_RELOC_HALF_SECTDIFF" };
if (r_type > 9)
res = "Unknown";
else
res = Table[r_type];
break;
}
case Triple::ppc: {
static const char *const Table[] = {
"PPC_RELOC_VANILLA",
"PPC_RELOC_PAIR",
"PPC_RELOC_BR14",
"PPC_RELOC_BR24",
"PPC_RELOC_HI16",
"PPC_RELOC_LO16",
"PPC_RELOC_HA16",
"PPC_RELOC_LO14",
"PPC_RELOC_SECTDIFF",
"PPC_RELOC_PB_LA_PTR",
"PPC_RELOC_HI16_SECTDIFF",
"PPC_RELOC_LO16_SECTDIFF",
"PPC_RELOC_HA16_SECTDIFF",
"PPC_RELOC_JBSR",
"PPC_RELOC_LO14_SECTDIFF",
"PPC_RELOC_LOCAL_SECTDIFF" };
res = Table[r_type];
break;
}
case Triple::UnknownArch:
res = "Unknown";
break;
}
Result.append(res.begin(), res.end());
return object_error::success;
}
error_code MachOObjectFile::getRelocationAdditionalInfo(DataRefImpl Rel,
int64_t &Res) const {
InMemoryStruct<macho::RelocationEntry> RE;
getRelocation(Rel, RE);
bool isExtern = (RE->Word1 >> 27) & 1;
Res = 0;
if (!isExtern) {
const uint8_t* sectAddress = base();
if (MachOObj->is64Bit()) {
InMemoryStruct<macho::Section64> Sect;
getSection64(Sections[Rel.d.b], Sect);
sectAddress += Sect->Offset;
} else {
InMemoryStruct<macho::Section> Sect;
getSection(Sections[Rel.d.b], Sect);
sectAddress += Sect->Offset;
}
Res = reinterpret_cast<uintptr_t>(sectAddress);
}
return object_error::success;
}
// Helper to advance a section or symbol iterator multiple increments at a time.
template<class T>
error_code advance(T &it, size_t Val) {
error_code ec;
while (Val--) {
it.increment(ec);
}
return ec;
}
template<class T>
void advanceTo(T &it, size_t Val) {
if (error_code ec = advance(it, Val))
report_fatal_error(ec.message());
}
void MachOObjectFile::printRelocationTargetName(
InMemoryStruct<macho::RelocationEntry>& RE,
raw_string_ostream &fmt) const {
unsigned Arch = getArch();
bool isScattered = (Arch != Triple::x86_64) &&
(RE->Word0 & macho::RF_Scattered);
// Target of a scattered relocation is an address. In the interest of
// generating pretty output, scan through the symbol table looking for a
// symbol that aligns with that address. If we find one, print it.
// Otherwise, we just print the hex address of the target.
if (isScattered) {
uint32_t Val = RE->Word1;
error_code ec;
for (symbol_iterator SI = begin_symbols(), SE = end_symbols(); SI != SE;
SI.increment(ec)) {
if (ec) report_fatal_error(ec.message());
uint64_t Addr;
StringRef Name;
if ((ec = SI->getAddress(Addr)))
report_fatal_error(ec.message());
if (Addr != Val) continue;
if ((ec = SI->getName(Name)))
report_fatal_error(ec.message());
fmt << Name;
return;
}
// If we couldn't find a symbol that this relocation refers to, try
// to find a section beginning instead.
for (section_iterator SI = begin_sections(), SE = end_sections(); SI != SE;
SI.increment(ec)) {
if (ec) report_fatal_error(ec.message());
uint64_t Addr;
StringRef Name;
if ((ec = SI->getAddress(Addr)))
report_fatal_error(ec.message());
if (Addr != Val) continue;
if ((ec = SI->getName(Name)))
report_fatal_error(ec.message());
fmt << Name;
return;
}
fmt << format("0x%x", Val);
return;
}
StringRef S;
bool isExtern = (RE->Word1 >> 27) & 1;
uint32_t Val = RE->Word1 & 0xFFFFFF;
if (isExtern) {
symbol_iterator SI = begin_symbols();
advanceTo(SI, Val);
SI->getName(S);
} else {
section_iterator SI = begin_sections();
advanceTo(SI, Val);
SI->getName(S);
}
fmt << S;
}
error_code MachOObjectFile::getRelocationValueString(DataRefImpl Rel,
SmallVectorImpl<char> &Result) const {
InMemoryStruct<macho::RelocationEntry> RE;
getRelocation(Rel, RE);
unsigned Arch = getArch();
bool isScattered = (Arch != Triple::x86_64) &&
(RE->Word0 & macho::RF_Scattered);
std::string fmtbuf;
raw_string_ostream fmt(fmtbuf);
unsigned Type;
if (isScattered)
Type = (RE->Word0 >> 24) & 0xF;
else
Type = (RE->Word1 >> 28) & 0xF;
bool isPCRel;
if (isScattered)
isPCRel = ((RE->Word0 >> 30) & 1);
else
isPCRel = ((RE->Word1 >> 24) & 1);
// Determine any addends that should be displayed with the relocation.
// These require decoding the relocation type, which is triple-specific.
// X86_64 has entirely custom relocation types.
if (Arch == Triple::x86_64) {
bool isPCRel = ((RE->Word1 >> 24) & 1);
switch (Type) {
case macho::RIT_X86_64_GOTLoad: // X86_64_RELOC_GOT_LOAD
case macho::RIT_X86_64_GOT: { // X86_64_RELOC_GOT
printRelocationTargetName(RE, fmt);
fmt << "@GOT";
if (isPCRel) fmt << "PCREL";
break;
}
case macho::RIT_X86_64_Subtractor: { // X86_64_RELOC_SUBTRACTOR
InMemoryStruct<macho::RelocationEntry> RENext;
DataRefImpl RelNext = Rel;
RelNext.d.a++;
getRelocation(RelNext, RENext);
// X86_64_SUBTRACTOR must be followed by a relocation of type
// X86_64_RELOC_UNSIGNED.
// NOTE: Scattered relocations don't exist on x86_64.
unsigned RType = (RENext->Word1 >> 28) & 0xF;
if (RType != 0)
report_fatal_error("Expected X86_64_RELOC_UNSIGNED after "
"X86_64_RELOC_SUBTRACTOR.");
// The X86_64_RELOC_UNSIGNED contains the minuend symbol,
// X86_64_SUBTRACTOR contains to the subtrahend.
printRelocationTargetName(RENext, fmt);
fmt << "-";
printRelocationTargetName(RE, fmt);
}
case macho::RIT_X86_64_TLV:
printRelocationTargetName(RE, fmt);
fmt << "@TLV";
if (isPCRel) fmt << "P";
break;
case macho::RIT_X86_64_Signed1: // X86_64_RELOC_SIGNED1
printRelocationTargetName(RE, fmt);
fmt << "-1";
break;
case macho::RIT_X86_64_Signed2: // X86_64_RELOC_SIGNED2
printRelocationTargetName(RE, fmt);
fmt << "-2";
break;
case macho::RIT_X86_64_Signed4: // X86_64_RELOC_SIGNED4
printRelocationTargetName(RE, fmt);
fmt << "-4";
break;
default:
printRelocationTargetName(RE, fmt);
break;
}
// X86 and ARM share some relocation types in common.
} else if (Arch == Triple::x86 || Arch == Triple::arm) {
// Generic relocation types...
switch (Type) {
case macho::RIT_Pair: // GENERIC_RELOC_PAIR - prints no info
return object_error::success;
case macho::RIT_Difference: { // GENERIC_RELOC_SECTDIFF
InMemoryStruct<macho::RelocationEntry> RENext;
DataRefImpl RelNext = Rel;
RelNext.d.a++;
getRelocation(RelNext, RENext);
// X86 sect diff's must be followed by a relocation of type
// GENERIC_RELOC_PAIR.
bool isNextScattered = (Arch != Triple::x86_64) &&
(RENext->Word0 & macho::RF_Scattered);
unsigned RType;
if (isNextScattered)
RType = (RENext->Word0 >> 24) & 0xF;
else
RType = (RENext->Word1 >> 28) & 0xF;
if (RType != 1)
report_fatal_error("Expected GENERIC_RELOC_PAIR after "
"GENERIC_RELOC_SECTDIFF.");
printRelocationTargetName(RE, fmt);
fmt << "-";
printRelocationTargetName(RENext, fmt);
break;
}
}
if (Arch == Triple::x86) {
// All X86 relocations that need special printing were already
// handled in the generic code.
switch (Type) {
case macho::RIT_Generic_LocalDifference:{// GENERIC_RELOC_LOCAL_SECTDIFF
InMemoryStruct<macho::RelocationEntry> RENext;
DataRefImpl RelNext = Rel;
RelNext.d.a++;
getRelocation(RelNext, RENext);
// X86 sect diff's must be followed by a relocation of type
// GENERIC_RELOC_PAIR.
bool isNextScattered = (Arch != Triple::x86_64) &&
(RENext->Word0 & macho::RF_Scattered);
unsigned RType;
if (isNextScattered)
RType = (RENext->Word0 >> 24) & 0xF;
else
RType = (RENext->Word1 >> 28) & 0xF;
if (RType != 1)
report_fatal_error("Expected GENERIC_RELOC_PAIR after "
"GENERIC_RELOC_LOCAL_SECTDIFF.");
printRelocationTargetName(RE, fmt);
fmt << "-";
printRelocationTargetName(RENext, fmt);
break;
}
case macho::RIT_Generic_TLV: {
printRelocationTargetName(RE, fmt);
fmt << "@TLV";
if (isPCRel) fmt << "P";
break;
}
default:
printRelocationTargetName(RE, fmt);
}
} else { // ARM-specific relocations
switch (Type) {
case macho::RIT_ARM_Half: // ARM_RELOC_HALF
case macho::RIT_ARM_HalfDifference: { // ARM_RELOC_HALF_SECTDIFF
// Half relocations steal a bit from the length field to encode
// whether this is an upper16 or a lower16 relocation.
bool isUpper;
if (isScattered)
isUpper = (RE->Word0 >> 28) & 1;
else
isUpper = (RE->Word1 >> 25) & 1;
if (isUpper)
fmt << ":upper16:(";
else
fmt << ":lower16:(";
printRelocationTargetName(RE, fmt);
InMemoryStruct<macho::RelocationEntry> RENext;
DataRefImpl RelNext = Rel;
RelNext.d.a++;
getRelocation(RelNext, RENext);
// ARM half relocs must be followed by a relocation of type
// ARM_RELOC_PAIR.
bool isNextScattered = (Arch != Triple::x86_64) &&
(RENext->Word0 & macho::RF_Scattered);
unsigned RType;
if (isNextScattered)
RType = (RENext->Word0 >> 24) & 0xF;
else
RType = (RENext->Word1 >> 28) & 0xF;
if (RType != 1)
report_fatal_error("Expected ARM_RELOC_PAIR after "
"GENERIC_RELOC_HALF");
// NOTE: The half of the target virtual address is stashed in the
// address field of the secondary relocation, but we can't reverse
// engineer the constant offset from it without decoding the movw/movt
// instruction to find the other half in its immediate field.
// ARM_RELOC_HALF_SECTDIFF encodes the second section in the
// symbol/section pointer of the follow-on relocation.
if (Type == macho::RIT_ARM_HalfDifference) {
fmt << "-";
printRelocationTargetName(RENext, fmt);
}
fmt << ")";
break;
}
default: {
printRelocationTargetName(RE, fmt);
}
}
}
} else
printRelocationTargetName(RE, fmt);
fmt.flush();
Result.append(fmtbuf.begin(), fmtbuf.end());
return object_error::success;
}
error_code MachOObjectFile::getRelocationHidden(DataRefImpl Rel,
bool &Result) const {
InMemoryStruct<macho::RelocationEntry> RE;
getRelocation(Rel, RE);
unsigned Arch = getArch();
bool isScattered = (Arch != Triple::x86_64) &&
(RE->Word0 & macho::RF_Scattered);
unsigned Type;
if (isScattered)
Type = (RE->Word0 >> 24) & 0xF;
else
Type = (RE->Word1 >> 28) & 0xF;
Result = false;
// On arches that use the generic relocations, GENERIC_RELOC_PAIR
// is always hidden.
if (Arch == Triple::x86 || Arch == Triple::arm) {
if (Type == macho::RIT_Pair) Result = true;
} else if (Arch == Triple::x86_64) {
// On x86_64, X86_64_RELOC_UNSIGNED is hidden only when it follows
// an X864_64_RELOC_SUBTRACTOR.
if (Type == macho::RIT_X86_64_Unsigned && Rel.d.a > 0) {
DataRefImpl RelPrev = Rel;
RelPrev.d.a--;
InMemoryStruct<macho::RelocationEntry> REPrev;
getRelocation(RelPrev, REPrev);
unsigned PrevType = (REPrev->Word1 >> 28) & 0xF;
if (PrevType == macho::RIT_X86_64_Subtractor) Result = true;
}
}
return object_error::success;
}
error_code MachOObjectFile::getLibraryNext(DataRefImpl LibData,
LibraryRef &Res) const {
report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
}
error_code MachOObjectFile::getLibraryPath(DataRefImpl LibData,
StringRef &Res) const {
report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
}
/*===-- Miscellaneous -----------------------------------------------------===*/
uint8_t MachOObjectFile::getBytesInAddress() const {
return MachOObj->is64Bit() ? 8 : 4;
}
StringRef MachOObjectFile::getFileFormatName() const {
if (!MachOObj->is64Bit()) {
switch (MachOObj->getHeader().CPUType) {
case llvm::MachO::CPUTypeI386:
return "Mach-O 32-bit i386";
case llvm::MachO::CPUTypeARM:
return "Mach-O arm";
case llvm::MachO::CPUTypePowerPC:
return "Mach-O 32-bit ppc";
default:
assert((MachOObj->getHeader().CPUType & llvm::MachO::CPUArchABI64) == 0 &&
"64-bit object file when we're not 64-bit?");
return "Mach-O 32-bit unknown";
}
}
switch (MachOObj->getHeader().CPUType) {
case llvm::MachO::CPUTypeX86_64:
return "Mach-O 64-bit x86-64";
case llvm::MachO::CPUTypePowerPC64:
return "Mach-O 64-bit ppc64";
default:
assert((MachOObj->getHeader().CPUType & llvm::MachO::CPUArchABI64) == 1 &&
"32-bit object file when we're 64-bit?");
return "Mach-O 64-bit unknown";
}
}
unsigned MachOObjectFile::getArch() const {
switch (MachOObj->getHeader().CPUType) {
case llvm::MachO::CPUTypeI386:
return Triple::x86;
case llvm::MachO::CPUTypeX86_64:
return Triple::x86_64;
case llvm::MachO::CPUTypeARM:
return Triple::arm;
case llvm::MachO::CPUTypePowerPC:
return Triple::ppc;
case llvm::MachO::CPUTypePowerPC64:
return Triple::ppc64;
default:
return Triple::UnknownArch;
}
}
} // end namespace object
} // end namespace llvm