llvm-6502/tools/obj2yaml/coff2yaml.cpp
David Majnemer f1198da05c MC: Add support for BigObj
Teach WinCOFFObjectWriter how to write -mbig-obj style object files;
these object files allow for more sections inside an object file.

Our support for BigObj is notably different from binutils and cl: we
implicitly upgrade object files to BigObj instead of asking the user to
compile the same file *again* but with another flag.  This matches up
with how LLVM treats ELF variants.

This was tested by forcing LLVM to always emit BigObj files and running
the entire test suite.  A specific test has also been added.

I've lowered the maximum number of sections in a normal COFF file,
VS "14" CTP 3 supports no more than 65279 sections.  This is important
otherwise we might not switch to BigObj quickly enough, leaving us with
a COFF file that we couldn't link.

yaml2obj support is all that remains to implement.

Differential Revision: http://reviews.llvm.org/D5349

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217812 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-15 19:42:42 +00:00

217 lines
7.7 KiB
C++

//===------ utils/obj2yaml.cpp - obj2yaml conversion tool -------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "obj2yaml.h"
#include "llvm/Object/COFF.h"
#include "llvm/Object/COFFYAML.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/YAMLTraits.h"
using namespace llvm;
namespace {
class COFFDumper {
const object::COFFObjectFile &Obj;
COFFYAML::Object YAMLObj;
void dumpHeader();
void dumpSections(unsigned numSections);
void dumpSymbols(unsigned numSymbols);
public:
COFFDumper(const object::COFFObjectFile &Obj);
COFFYAML::Object &getYAMLObj();
};
}
COFFDumper::COFFDumper(const object::COFFObjectFile &Obj) : Obj(Obj) {
dumpHeader();
dumpSections(Obj.getNumberOfSections());
dumpSymbols(Obj.getNumberOfSymbols());
}
void COFFDumper::dumpHeader() {
YAMLObj.Header.Machine = Obj.getMachine();
YAMLObj.Header.Characteristics = Obj.getCharacteristics();
}
void COFFDumper::dumpSections(unsigned NumSections) {
std::vector<COFFYAML::Section> &Sections = YAMLObj.Sections;
for (const auto &Section : Obj.sections()) {
const object::coff_section *Sect = Obj.getCOFFSection(Section);
COFFYAML::Section Sec;
Sec.Name = Sect->Name; // FIXME: check the null termination!
uint32_t Characteristics = Sect->Characteristics;
Sec.Header.Characteristics = Characteristics;
Sec.Alignment = 1 << (((Characteristics >> 20) & 0xf) - 1);
ArrayRef<uint8_t> sectionData;
Obj.getSectionContents(Sect, sectionData);
Sec.SectionData = yaml::BinaryRef(sectionData);
std::vector<COFFYAML::Relocation> Relocations;
for (const auto &Reloc : Section.relocations()) {
const object::coff_relocation *reloc = Obj.getCOFFRelocation(Reloc);
COFFYAML::Relocation Rel;
object::symbol_iterator Sym = Reloc.getSymbol();
Sym->getName(Rel.SymbolName);
Rel.VirtualAddress = reloc->VirtualAddress;
Rel.Type = reloc->Type;
Relocations.push_back(Rel);
}
Sec.Relocations = Relocations;
Sections.push_back(Sec);
}
}
static void
dumpFunctionDefinition(COFFYAML::Symbol *Sym,
const object::coff_aux_function_definition *ObjFD) {
COFF::AuxiliaryFunctionDefinition YAMLFD;
YAMLFD.TagIndex = ObjFD->TagIndex;
YAMLFD.TotalSize = ObjFD->TotalSize;
YAMLFD.PointerToLinenumber = ObjFD->PointerToLinenumber;
YAMLFD.PointerToNextFunction = ObjFD->PointerToNextFunction;
Sym->FunctionDefinition = YAMLFD;
}
static void
dumpbfAndEfLineInfo(COFFYAML::Symbol *Sym,
const object::coff_aux_bf_and_ef_symbol *ObjBES) {
COFF::AuxiliarybfAndefSymbol YAMLAAS;
YAMLAAS.Linenumber = ObjBES->Linenumber;
YAMLAAS.PointerToNextFunction = ObjBES->PointerToNextFunction;
Sym->bfAndefSymbol = YAMLAAS;
}
static void dumpWeakExternal(COFFYAML::Symbol *Sym,
const object::coff_aux_weak_external *ObjWE) {
COFF::AuxiliaryWeakExternal YAMLWE;
YAMLWE.TagIndex = ObjWE->TagIndex;
YAMLWE.Characteristics = ObjWE->Characteristics;
Sym->WeakExternal = YAMLWE;
}
static void
dumpSectionDefinition(COFFYAML::Symbol *Sym,
const object::coff_aux_section_definition *ObjSD,
bool IsBigObj) {
COFF::AuxiliarySectionDefinition YAMLASD;
int32_t AuxNumber = ObjSD->getNumber(IsBigObj);
YAMLASD.Length = ObjSD->Length;
YAMLASD.NumberOfRelocations = ObjSD->NumberOfRelocations;
YAMLASD.NumberOfLinenumbers = ObjSD->NumberOfLinenumbers;
YAMLASD.CheckSum = ObjSD->CheckSum;
YAMLASD.Number = AuxNumber;
YAMLASD.Selection = ObjSD->Selection;
Sym->SectionDefinition = YAMLASD;
}
static void
dumpCLRTokenDefinition(COFFYAML::Symbol *Sym,
const object::coff_aux_clr_token *ObjCLRToken) {
COFF::AuxiliaryCLRToken YAMLCLRToken;
YAMLCLRToken.AuxType = ObjCLRToken->AuxType;
YAMLCLRToken.SymbolTableIndex = ObjCLRToken->SymbolTableIndex;
Sym->CLRToken = YAMLCLRToken;
}
void COFFDumper::dumpSymbols(unsigned NumSymbols) {
std::vector<COFFYAML::Symbol> &Symbols = YAMLObj.Symbols;
for (const auto &S : Obj.symbols()) {
object::COFFSymbolRef Symbol = Obj.getCOFFSymbol(S);
COFFYAML::Symbol Sym;
Obj.getSymbolName(Symbol, Sym.Name);
Sym.SimpleType = COFF::SymbolBaseType(Symbol.getBaseType());
Sym.ComplexType = COFF::SymbolComplexType(Symbol.getComplexType());
Sym.Header.StorageClass = Symbol.getStorageClass();
Sym.Header.Value = Symbol.getValue();
Sym.Header.SectionNumber = Symbol.getSectionNumber();
Sym.Header.NumberOfAuxSymbols = Symbol.getNumberOfAuxSymbols();
if (Symbol.getNumberOfAuxSymbols() > 0) {
ArrayRef<uint8_t> AuxData = Obj.getSymbolAuxData(Symbol);
if (Symbol.isFunctionDefinition()) {
// This symbol represents a function definition.
assert(Symbol.getNumberOfAuxSymbols() == 1 &&
"Expected a single aux symbol to describe this function!");
const object::coff_aux_function_definition *ObjFD =
reinterpret_cast<const object::coff_aux_function_definition *>(
AuxData.data());
dumpFunctionDefinition(&Sym, ObjFD);
} else if (Symbol.isFunctionLineInfo()) {
// This symbol describes function line number information.
assert(Symbol.getNumberOfAuxSymbols() == 1 &&
"Expected a single aux symbol to describe this function!");
const object::coff_aux_bf_and_ef_symbol *ObjBES =
reinterpret_cast<const object::coff_aux_bf_and_ef_symbol *>(
AuxData.data());
dumpbfAndEfLineInfo(&Sym, ObjBES);
} else if (Symbol.isWeakExternal()) {
// This symbol represents a weak external definition.
assert(Symbol.getNumberOfAuxSymbols() == 1 &&
"Expected a single aux symbol to describe this weak symbol!");
const object::coff_aux_weak_external *ObjWE =
reinterpret_cast<const object::coff_aux_weak_external *>(
AuxData.data());
dumpWeakExternal(&Sym, ObjWE);
} else if (Symbol.isFileRecord()) {
// This symbol represents a file record.
Sym.File = StringRef(reinterpret_cast<const char *>(AuxData.data()),
Symbol.getNumberOfAuxSymbols() *
Obj.getSymbolTableEntrySize())
.rtrim(StringRef("\0", /*length=*/1));
} else if (Symbol.isSectionDefinition()) {
// This symbol represents a section definition.
assert(Symbol.getNumberOfAuxSymbols() == 1 &&
"Expected a single aux symbol to describe this section!");
const object::coff_aux_section_definition *ObjSD =
reinterpret_cast<const object::coff_aux_section_definition *>(
AuxData.data());
dumpSectionDefinition(&Sym, ObjSD, Symbol.isBigObj());
} else if (Symbol.isCLRToken()) {
// This symbol represents a CLR token definition.
assert(Symbol.getNumberOfAuxSymbols() == 1 &&
"Expected a single aux symbol to describe this CLR Token!");
const object::coff_aux_clr_token *ObjCLRToken =
reinterpret_cast<const object::coff_aux_clr_token *>(
AuxData.data());
dumpCLRTokenDefinition(&Sym, ObjCLRToken);
} else {
llvm_unreachable("Unhandled auxiliary symbol!");
}
}
Symbols.push_back(Sym);
}
}
COFFYAML::Object &COFFDumper::getYAMLObj() {
return YAMLObj;
}
std::error_code coff2yaml(raw_ostream &Out, const object::COFFObjectFile &Obj) {
COFFDumper Dumper(Obj);
yaml::Output Yout(Out);
Yout << Dumper.getYAMLObj();
return object::object_error::success;
}