static void getSectionsAndSymbols(const macho::Header &Header,
MachOObjectFile *MachOObj,
InMemoryStruct<macho::SymtabLoadCommand> *SymtabLC,
std::vector<SectionRef> &Sections,
std::vector<SymbolRef> &Symbols,
SmallVectorImpl<uint64_t> &FoundFns) {
error_code ec;
for (symbol_iterator SI = MachOObj->begin_symbols(),
SE = MachOObj->end_symbols(); SI != SE; SI.increment(ec))
Symbols.push_back(*SI);
for (section_iterator SI = MachOObj->begin_sections(),
SE = MachOObj->end_sections(); SI != SE; SI.increment(ec)) {
SectionRef SR = *SI;
StringRef SectName;
SR.getName(SectName);
Sections.push_back(*SI);
}
for (unsigned i = 0; i != Header.NumLoadCommands; ++i) {
const MachOObject::LoadCommandInfo &LCI =
MachOObj->getObject()->getLoadCommandInfo(i);
if (LCI.Command.Type == macho::LCT_FunctionStarts) {
// We found a function starts segment, parse the addresses for later
// consumption.
InMemoryStruct<macho::LinkeditDataLoadCommand> LLC;
MachOObj->getObject()->ReadLinkeditDataLoadCommand(LCI, LLC);
MachOObj->getObject()->ReadULEB128s(LLC->DataOffset, FoundFns);
}
}
}
/// Given a relocation from __compact_unwind, consisting of the RelocationRef
/// and data being relocated, determine the best base Name and Addend to use for
/// display purposes.
///
/// 1. An Extern relocation will directly reference a symbol (and the data is
/// then already an addend), so use that.
/// 2. Otherwise the data is an offset in the object file's layout; try to find
// a symbol before it in the same section, and use the offset from there.
/// 3. Finally, if all that fails, fall back to an offset from the start of the
/// referenced section.
static void findUnwindRelocNameAddend(const MachOObjectFile *Obj,
std::map<uint64_t, SymbolRef> &Symbols,
const RelocationRef &Reloc,
uint64_t Addr,
StringRef &Name, uint64_t &Addend) {
if (Reloc.getSymbol() != Obj->symbol_end()) {
Reloc.getSymbol()->getName(Name);
Addend = Addr;
return;
}
auto RE = Obj->getRelocation(Reloc.getRawDataRefImpl());
SectionRef RelocSection = Obj->getRelocationSection(RE);
uint64_t SectionAddr;
RelocSection.getAddress(SectionAddr);
auto Sym = Symbols.upper_bound(Addr);
if (Sym == Symbols.begin()) {
// The first symbol in the object is after this reference, the best we can
// do is section-relative notation.
RelocSection.getName(Name);
Addend = Addr - SectionAddr;
return;
}
// Go back one so that SymbolAddress <= Addr.
--Sym;
section_iterator SymSection = Obj->section_end();
Sym->second.getSection(SymSection);
if (RelocSection == *SymSection) {
// There's a valid symbol in the same section before this reference.
Sym->second.getName(Name);
Addend = Addr - Sym->first;
return;
}
// There is a symbol before this reference, but it's in a different
// section. Probably not helpful to mention it, so use the section name.
RelocSection.getName(Name);
Addend = Addr - SectionAddr;
}
explicit section(const SectionRef& sec) {
StringRef name;
if(error_code err = sec.getName(name))
llvm_binary_fail(err);
this->name_ = name.str();
if (error_code err = sec.getAddress(this->addr_))
llvm_binary_fail(err);
if (error_code err = sec.getSize(this->size_))
llvm_binary_fail(err);
}
static void
getSectionsAndSymbols(const MachO::mach_header Header,
MachOObjectFile *MachOObj,
std::vector<SectionRef> &Sections,
std::vector<SymbolRef> &Symbols,
SmallVectorImpl<uint64_t> &FoundFns,
uint64_t &BaseSegmentAddress) {
for (symbol_iterator SI = MachOObj->symbol_begin(),
SE = MachOObj->symbol_end();
SI != SE; ++SI)
Symbols.push_back(*SI);
for (section_iterator SI = MachOObj->section_begin(),
SE = MachOObj->section_end();
SI != SE; ++SI) {
SectionRef SR = *SI;
StringRef SectName;
SR.getName(SectName);
Sections.push_back(*SI);
}
MachOObjectFile::LoadCommandInfo Command =
MachOObj->getFirstLoadCommandInfo();
bool BaseSegmentAddressSet = false;
for (unsigned i = 0; ; ++i) {
if (Command.C.cmd == MachO::LC_FUNCTION_STARTS) {
// We found a function starts segment, parse the addresses for later
// consumption.
MachO::linkedit_data_command LLC =
MachOObj->getLinkeditDataLoadCommand(Command);
MachOObj->ReadULEB128s(LLC.dataoff, FoundFns);
}
else if (Command.C.cmd == MachO::LC_SEGMENT) {
MachO::segment_command SLC =
MachOObj->getSegmentLoadCommand(Command);
StringRef SegName = SLC.segname;
if(!BaseSegmentAddressSet && SegName != "__PAGEZERO") {
BaseSegmentAddressSet = true;
BaseSegmentAddress = SLC.vmaddr;
}
}
if (i == Header.ncmds - 1)
break;
else
Command = MachOObj->getNextLoadCommandInfo(Command);
}
}
/// Return true if the provided section is an offload section and return the
/// triple by reference.
static bool IsOffloadSection(SectionRef CurSection,
StringRef &OffloadTriple) {
StringRef SectionName;
CurSection.getName(SectionName);
if (SectionName.empty())
return false;
// If it does not start with the reserved suffix, just skip this section.
if (!SectionName.startswith(OFFLOAD_BUNDLER_MAGIC_STR))
return false;
// Return the triple that is right after the reserved prefix.
OffloadTriple = SectionName.substr(sizeof(OFFLOAD_BUNDLER_MAGIC_STR) - 1);
return true;
}
static void
getSectionsAndSymbols(const macho::Header Header,
MachOObjectFile *MachOObj,
std::vector<SectionRef> &Sections,
std::vector<SymbolRef> &Symbols,
SmallVectorImpl<uint64_t> &FoundFns) {
error_code ec;
for (symbol_iterator SI = MachOObj->begin_symbols(),
SE = MachOObj->end_symbols(); SI != SE; SI.increment(ec))
Symbols.push_back(*SI);
for (section_iterator SI = MachOObj->begin_sections(),
SE = MachOObj->end_sections(); SI != SE; SI.increment(ec)) {
SectionRef SR = *SI;
StringRef SectName;
SR.getName(SectName);
Sections.push_back(*SI);
}
MachOObjectFile::LoadCommandInfo Command =
MachOObj->getFirstLoadCommandInfo();
for (unsigned i = 0; ; ++i) {
if (Command.C.Type == macho::LCT_FunctionStarts) {
// We found a function starts segment, parse the addresses for later
// consumption.
macho::LinkeditDataLoadCommand LLC =
MachOObj->getLinkeditDataLoadCommand(Command);
MachOObj->ReadULEB128s(LLC.DataOffset, FoundFns);
}
if (i == Header.NumLoadCommands - 1)
break;
else
Command = MachOObj->getNextLoadCommandInfo(Command);
}
}
unsigned RuntimeDyldImpl::emitSection(ObjectImage &Obj,
const SectionRef &Section,
bool IsCode) {
unsigned StubBufSize = 0,
StubSize = getMaxStubSize();
error_code err;
if (StubSize > 0) {
for (relocation_iterator i = Section.begin_relocations(),
e = Section.end_relocations(); i != e; i.increment(err), Check(err))
StubBufSize += StubSize;
}
StringRef data;
uint64_t Alignment64;
Check(Section.getContents(data));
Check(Section.getAlignment(Alignment64));
unsigned Alignment = (unsigned)Alignment64 & 0xffffffffL;
bool IsRequired;
bool IsVirtual;
bool IsZeroInit;
uint64_t DataSize;
StringRef Name;
Check(Section.isRequiredForExecution(IsRequired));
Check(Section.isVirtual(IsVirtual));
Check(Section.isZeroInit(IsZeroInit));
Check(Section.getSize(DataSize));
Check(Section.getName(Name));
unsigned Allocate;
unsigned SectionID = Sections.size();
uint8_t *Addr;
const char *pData = 0;
// Some sections, such as debug info, don't need to be loaded for execution.
// Leave those where they are.
if (IsRequired) {
Allocate = DataSize + StubBufSize;
Addr = IsCode
? MemMgr->allocateCodeSection(Allocate, Alignment, SectionID)
: MemMgr->allocateDataSection(Allocate, Alignment, SectionID);
if (!Addr)
report_fatal_error("Unable to allocate section memory!");
// Virtual sections have no data in the object image, so leave pData = 0
if (!IsVirtual)
pData = data.data();
// Zero-initialize or copy the data from the image
if (IsZeroInit || IsVirtual)
memset(Addr, 0, DataSize);
else
memcpy(Addr, pData, DataSize);
DEBUG(dbgs() << "emitSection SectionID: " << SectionID
<< " Name: " << Name
<< " obj addr: " << format("%p", pData)
<< " new addr: " << format("%p", Addr)
<< " DataSize: " << DataSize
<< " StubBufSize: " << StubBufSize
<< " Allocate: " << Allocate
<< "\n");
Obj.updateSectionAddress(Section, (uint64_t)Addr);
}
else {
// Even if we didn't load the section, we need to record an entry for it
// to handle later processing (and by 'handle' I mean don't do anything
// with these sections).
Allocate = 0;
Addr = 0;
DEBUG(dbgs() << "emitSection SectionID: " << SectionID
<< " Name: " << Name
<< " obj addr: " << format("%p", data.data())
<< " new addr: 0"
<< " DataSize: " << DataSize
<< " StubBufSize: " << StubBufSize
<< " Allocate: " << Allocate
<< "\n");
}
Sections.push_back(SectionEntry(Name, Addr, Allocate, DataSize,
(uintptr_t)pData));
return SectionID;
}
unsigned RuntimeDyldImpl::emitSection(ObjectImage &Obj,
const SectionRef &Section,
bool IsCode) {
unsigned StubBufSize = 0,
StubSize = getMaxStubSize();
error_code err;
const ObjectFile *ObjFile = Obj.getObjectFile();
// FIXME: this is an inefficient way to handle this. We should computed the
// necessary section allocation size in loadObject by walking all the sections
// once.
if (StubSize > 0) {
for (section_iterator SI = ObjFile->begin_sections(),
SE = ObjFile->end_sections();
SI != SE; SI.increment(err), Check(err)) {
section_iterator RelSecI = SI->getRelocatedSection();
if (!(RelSecI == Section))
continue;
for (relocation_iterator I = SI->begin_relocations(),
E = SI->end_relocations(); I != E; I.increment(err), Check(err)) {
StubBufSize += StubSize;
}
}
}
StringRef data;
uint64_t Alignment64;
Check(Section.getContents(data));
Check(Section.getAlignment(Alignment64));
unsigned Alignment = (unsigned)Alignment64 & 0xffffffffL;
bool IsRequired;
bool IsVirtual;
bool IsZeroInit;
bool IsReadOnly;
uint64_t DataSize;
StringRef Name;
Check(Section.isRequiredForExecution(IsRequired));
Check(Section.isVirtual(IsVirtual));
Check(Section.isZeroInit(IsZeroInit));
Check(Section.isReadOnlyData(IsReadOnly));
Check(Section.getSize(DataSize));
Check(Section.getName(Name));
if (StubSize > 0) {
unsigned StubAlignment = getStubAlignment();
unsigned EndAlignment = (DataSize | Alignment) & -(DataSize | Alignment);
if (StubAlignment > EndAlignment)
StubBufSize += StubAlignment - EndAlignment;
}
unsigned Allocate;
unsigned SectionID = Sections.size();
uint8_t *Addr;
const char *pData = 0;
// Some sections, such as debug info, don't need to be loaded for execution.
// Leave those where they are.
if (IsRequired) {
Allocate = DataSize + StubBufSize;
Addr = IsCode
? MemMgr->allocateCodeSection(Allocate, Alignment, SectionID)
: MemMgr->allocateDataSection(Allocate, Alignment, SectionID, IsReadOnly);
if (!Addr)
report_fatal_error("Unable to allocate section memory!");
// Virtual sections have no data in the object image, so leave pData = 0
if (!IsVirtual)
pData = data.data();
// Zero-initialize or copy the data from the image
if (IsZeroInit || IsVirtual)
memset(Addr, 0, DataSize);
else
memcpy(Addr, pData, DataSize);
DEBUG(dbgs() << "emitSection SectionID: " << SectionID
<< " Name: " << Name
<< " obj addr: " << format("%p", pData)
<< " new addr: " << format("%p", Addr)
<< " DataSize: " << DataSize
<< " StubBufSize: " << StubBufSize
<< " Allocate: " << Allocate
<< "\n");
Obj.updateSectionAddress(Section, (uint64_t)Addr);
}
else {
// Even if we didn't load the section, we need to record an entry for it
// to handle later processing (and by 'handle' I mean don't do anything
// with these sections).
Allocate = 0;
Addr = 0;
DEBUG(dbgs() << "emitSection SectionID: " << SectionID
<< " Name: " << Name
<< " obj addr: " << format("%p", data.data())
<< " new addr: 0"
<< " DataSize: " << DataSize
<< " StubBufSize: " << StubBufSize
<< " Allocate: " << Allocate
<< "\n");
}
Sections.push_back(SectionEntry(Name, Addr, DataSize, (uintptr_t)pData));
return SectionID;
}
unsigned RuntimeDyldImpl::emitSection(ObjectImage &Obj,
const SectionRef &Section, bool IsCode) {
StringRef data;
uint64_t Alignment64;
Check(Section.getContents(data));
Check(Section.getAlignment(Alignment64));
unsigned Alignment = (unsigned)Alignment64 & 0xffffffffL;
bool IsRequired;
bool IsVirtual;
bool IsZeroInit;
bool IsReadOnly;
uint64_t DataSize;
unsigned PaddingSize = 0;
unsigned StubBufSize = 0;
StringRef Name;
Check(Section.isRequiredForExecution(IsRequired));
Check(Section.isVirtual(IsVirtual));
Check(Section.isZeroInit(IsZeroInit));
Check(Section.isReadOnlyData(IsReadOnly));
Check(Section.getSize(DataSize));
Check(Section.getName(Name));
StubBufSize = computeSectionStubBufSize(Obj, Section);
// The .eh_frame section (at least on Linux) needs an extra four bytes padded
// with zeroes added at the end. For MachO objects, this section has a
// slightly different name, so this won't have any effect for MachO objects.
if (Name == ".eh_frame")
PaddingSize = 4;
uintptr_t Allocate;
unsigned SectionID = Sections.size();
uint8_t *Addr;
const char *pData = 0;
// Some sections, such as debug info, don't need to be loaded for execution.
// Leave those where they are.
if (IsRequired) {
Allocate = DataSize + PaddingSize + StubBufSize;
Addr = IsCode ? MemMgr->allocateCodeSection(Allocate, Alignment, SectionID,
Name)
: MemMgr->allocateDataSection(Allocate, Alignment, SectionID,
Name, IsReadOnly);
if (!Addr)
report_fatal_error("Unable to allocate section memory!");
// Virtual sections have no data in the object image, so leave pData = 0
if (!IsVirtual)
pData = data.data();
// Zero-initialize or copy the data from the image
if (IsZeroInit || IsVirtual)
memset(Addr, 0, DataSize);
else
memcpy(Addr, pData, DataSize);
// Fill in any extra bytes we allocated for padding
if (PaddingSize != 0) {
memset(Addr + DataSize, 0, PaddingSize);
// Update the DataSize variable so that the stub offset is set correctly.
DataSize += PaddingSize;
}
DEBUG(dbgs() << "emitSection SectionID: " << SectionID << " Name: " << Name
<< " obj addr: " << format("%p", pData)
<< " new addr: " << format("%p", Addr)
<< " DataSize: " << DataSize << " StubBufSize: " << StubBufSize
<< " Allocate: " << Allocate << "\n");
Obj.updateSectionAddress(Section, (uint64_t)Addr);
} else {
// Even if we didn't load the section, we need to record an entry for it
// to handle later processing (and by 'handle' I mean don't do anything
// with these sections).
Allocate = 0;
Addr = 0;
DEBUG(dbgs() << "emitSection SectionID: " << SectionID << " Name: " << Name
<< " obj addr: " << format("%p", data.data()) << " new addr: 0"
<< " DataSize: " << DataSize << " StubBufSize: " << StubBufSize
<< " Allocate: " << Allocate << "\n");
}
Sections.push_back(SectionEntry(Name, Addr, DataSize, (uintptr_t)pData));
return SectionID;
}
error_or<std::string> getName(const SectionRef &sec) {
StringRef name;
if (error_code ec = sec.getName(name))
return failure(ec.message());
return success(name.str());
}
