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

201 lines
6.5 KiB
C++

//===- ObjectFile.cpp - File format independent object file ---------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines a file format independent ObjectFile class.
//
//===----------------------------------------------------------------------===//
#include "llvm/Object/ObjectFile.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/BinaryFormat/Magic.h"
#include "llvm/Object/Binary.h"
#include "llvm/Object/COFF.h"
#include "llvm/Object/Error.h"
#include "llvm/Object/MachO.h"
#include "llvm/Object/Wasm.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ErrorOr.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <cstdint>
#include <memory>
#include <system_error>
using namespace llvm;
using namespace object;
raw_ostream &object::operator<<(raw_ostream &OS, const SectionedAddress &Addr) {
OS << "SectionedAddress{" << format_hex(Addr.Address, 10);
if (Addr.SectionIndex != SectionedAddress::UndefSection)
OS << ", " << Addr.SectionIndex;
return OS << "}";
}
void ObjectFile::anchor() {}
ObjectFile::ObjectFile(unsigned int Type, MemoryBufferRef Source)
: SymbolicFile(Type, Source) {}
bool SectionRef::containsSymbol(SymbolRef S) const {
Expected<section_iterator> SymSec = S.getSection();
if (!SymSec) {
// TODO: Actually report errors helpfully.
consumeError(SymSec.takeError());
return false;
}
return *this == **SymSec;
}
Expected<uint64_t> ObjectFile::getSymbolValue(DataRefImpl Ref) const {
if (Expected<uint32_t> FlagsOrErr = getSymbolFlags(Ref)) {
if (*FlagsOrErr & SymbolRef::SF_Undefined)
return 0;
if (*FlagsOrErr & SymbolRef::SF_Common)
return getCommonSymbolSize(Ref);
} else
// TODO: Test this error.
return FlagsOrErr.takeError();
return getSymbolValueImpl(Ref);
}
Error ObjectFile::printSymbolName(raw_ostream &OS, DataRefImpl Symb) const {
Expected<StringRef> Name = getSymbolName(Symb);
if (!Name)
return Name.takeError();
OS << *Name;
return Error::success();
}
uint32_t ObjectFile::getSymbolAlignment(DataRefImpl DRI) const { return 0; }
bool ObjectFile::isSectionBitcode(DataRefImpl Sec) const {
Expected<StringRef> NameOrErr = getSectionName(Sec);
if (NameOrErr)
return *NameOrErr == ".llvmbc";
consumeError(NameOrErr.takeError());
return false;
}
bool ObjectFile::isSectionStripped(DataRefImpl Sec) const { return false; }
bool ObjectFile::isBerkeleyText(DataRefImpl Sec) const {
return isSectionText(Sec);
}
bool ObjectFile::isBerkeleyData(DataRefImpl Sec) const {
return isSectionData(Sec);
}
bool ObjectFile::isDebugSection(StringRef SectionName) const {
return false;
}
Expected<section_iterator>
ObjectFile::getRelocatedSection(DataRefImpl Sec) const {
return section_iterator(SectionRef(Sec, this));
}
Triple ObjectFile::makeTriple() const {
Triple TheTriple;
auto Arch = getArch();
TheTriple.setArch(Triple::ArchType(Arch));
// For ARM targets, try to use the build attributes to build determine
// the build target. Target features are also added, but later during
// disassembly.
if (Arch == Triple::arm || Arch == Triple::armeb)
setARMSubArch(TheTriple);
// TheTriple defaults to ELF, and COFF doesn't have an environment:
// something we can do here is indicate that it is mach-o.
if (isMachO()) {
TheTriple.setObjectFormat(Triple::MachO);
} else if (isCOFF()) {
const auto COFFObj = cast<COFFObjectFile>(this);
if (COFFObj->getArch() == Triple::thumb)
TheTriple.setTriple("thumbv7-windows");
} else if (isXCOFF()) {
// XCOFF implies AIX.
TheTriple.setOS(Triple::AIX);
TheTriple.setObjectFormat(Triple::XCOFF);
}
return TheTriple;
}
Expected<std::unique_ptr<ObjectFile>>
ObjectFile::createObjectFile(MemoryBufferRef Object, file_magic Type,
bool InitContent) {
StringRef Data = Object.getBuffer();
if (Type == file_magic::unknown)
Type = identify_magic(Data);
switch (Type) {
case file_magic::unknown:
case file_magic::bitcode:
case file_magic::coff_cl_gl_object:
case file_magic::archive:
case file_magic::macho_universal_binary:
case file_magic::windows_resource:
case file_magic::pdb:
case file_magic::minidump:
return errorCodeToError(object_error::invalid_file_type);
case file_magic::tapi_file:
return errorCodeToError(object_error::invalid_file_type);
case file_magic::elf:
case file_magic::elf_relocatable:
case file_magic::elf_executable:
case file_magic::elf_shared_object:
case file_magic::elf_core:
return createELFObjectFile(Object, InitContent);
case file_magic::macho_object:
case file_magic::macho_executable:
case file_magic::macho_fixed_virtual_memory_shared_lib:
case file_magic::macho_core:
case file_magic::macho_preload_executable:
case file_magic::macho_dynamically_linked_shared_lib:
case file_magic::macho_dynamic_linker:
case file_magic::macho_bundle:
case file_magic::macho_dynamically_linked_shared_lib_stub:
case file_magic::macho_dsym_companion:
case file_magic::macho_kext_bundle:
return createMachOObjectFile(Object);
case file_magic::coff_object:
case file_magic::coff_import_library:
case file_magic::pecoff_executable:
return createCOFFObjectFile(Object);
case file_magic::xcoff_object_32:
return createXCOFFObjectFile(Object, Binary::ID_XCOFF32);
case file_magic::xcoff_object_64:
return createXCOFFObjectFile(Object, Binary::ID_XCOFF64);
case file_magic::wasm_object:
return createWasmObjectFile(Object);
}
llvm_unreachable("Unexpected Object File Type");
}
Expected<OwningBinary<ObjectFile>>
ObjectFile::createObjectFile(StringRef ObjectPath) {
ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
MemoryBuffer::getFile(ObjectPath);
if (std::error_code EC = FileOrErr.getError())
return errorCodeToError(EC);
std::unique_ptr<MemoryBuffer> Buffer = std::move(FileOrErr.get());
Expected<std::unique_ptr<ObjectFile>> ObjOrErr =
createObjectFile(Buffer->getMemBufferRef());
if (Error Err = ObjOrErr.takeError())
return std::move(Err);
std::unique_ptr<ObjectFile> Obj = std::move(ObjOrErr.get());
return OwningBinary<ObjectFile>(std::move(Obj), std::move(Buffer));
}