llvm-6502/tools/llvm-objdump/MachODump.cpp
Kevin Enderby 54154f3bf1 Teach llvm-objdump with the -macho parser how to use the data in code table
from the LC_DATA_IN_CODE load command.  And when disassembling print
the data in code formatted for the kind of data it and not disassemble those
bytes.

I added the format specific functionality to the derived class MachOObjectFile
since these tables only appears in Mach-O object files. This is my first
attempt to modify the libObject stuff so if folks have better suggestions
how to fit this in or suggestions on the implementation please let me know.

rdar://11791371


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183424 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-06 17:20:50 +00:00

470 lines
16 KiB
C++

//===-- MachODump.cpp - Object file dumping utility for llvm --------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the MachO-specific dumper for llvm-objdump.
//
//===----------------------------------------------------------------------===//
#include "llvm-objdump.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/Triple.h"
#include "llvm/DebugInfo/DIContext.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCDisassembler.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCInstPrinter.h"
#include "llvm/MC/MCInstrAnalysis.h"
#include "llvm/MC/MCInstrDesc.h"
#include "llvm/MC/MCInstrInfo.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/Object/MachO.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/GraphWriter.h"
#include "llvm/Support/MachO.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/TargetSelect.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/system_error.h"
#include <algorithm>
#include <cstring>
using namespace llvm;
using namespace object;
static cl::opt<bool>
UseDbg("g", cl::desc("Print line information from debug info if available"));
static cl::opt<std::string>
DSYMFile("dsym", cl::desc("Use .dSYM file for debug info"));
static const Target *GetTarget(const MachOObjectFile *MachOObj) {
// Figure out the target triple.
if (TripleName.empty()) {
llvm::Triple TT("unknown-unknown-unknown");
TT.setArch(Triple::ArchType(MachOObj->getArch()));
TripleName = TT.str();
}
// Get the target specific parser.
std::string Error;
const Target *TheTarget = TargetRegistry::lookupTarget(TripleName, Error);
if (TheTarget)
return TheTarget;
errs() << "llvm-objdump: error: unable to get target for '" << TripleName
<< "', see --version and --triple.\n";
return 0;
}
struct SymbolSorter {
bool operator()(const SymbolRef &A, const SymbolRef &B) {
SymbolRef::Type AType, BType;
A.getType(AType);
B.getType(BType);
uint64_t AAddr, BAddr;
if (AType != SymbolRef::ST_Function)
AAddr = 0;
else
A.getAddress(AAddr);
if (BType != SymbolRef::ST_Function)
BAddr = 0;
else
B.getAddress(BAddr);
return AAddr < BAddr;
}
};
// Types for the storted data in code table that is built before disassembly
// and the predicate function to sort them.
typedef std::pair<uint64_t, DiceRef> DiceTableEntry;
typedef std::vector<DiceTableEntry> DiceTable;
typedef DiceTable::iterator dice_table_iterator;
static bool
compareDiceTableEntries(const DiceTableEntry i,
const DiceTableEntry j) {
return i.first == j.first;
}
static void DumpDataInCode(const char *bytes, uint64_t Size,
unsigned short Kind) {
uint64_t Value;
switch (Kind) {
case macho::Data:
switch (Size) {
case 4:
Value = bytes[3] << 24 |
bytes[2] << 16 |
bytes[1] << 8 |
bytes[0];
outs() << "\t.long " << Value;
break;
case 2:
Value = bytes[1] << 8 |
bytes[0];
outs() << "\t.short " << Value;
break;
case 1:
Value = bytes[0];
outs() << "\t.byte " << Value;
break;
}
outs() << "\t@ KIND_DATA\n";
break;
case macho::JumpTable8:
Value = bytes[0];
outs() << "\t.byte " << Value << "\t@ KIND_JUMP_TABLE8";
break;
case macho::JumpTable16:
Value = bytes[1] << 8 |
bytes[0];
outs() << "\t.short " << Value << "\t@ KIND_JUMP_TABLE16";
break;
case macho::JumpTable32:
Value = bytes[3] << 24 |
bytes[2] << 16 |
bytes[1] << 8 |
bytes[0];
outs() << "\t.long " << Value << "\t@ KIND_JUMP_TABLE32";
break;
default:
outs() << "\t@ data in code kind = " << Kind << "\n";
break;
}
}
static void
getSectionsAndSymbols(const macho::Header Header,
MachOObjectFile *MachOObj,
std::vector<SectionRef> &Sections,
std::vector<SymbolRef> &Symbols,
SmallVectorImpl<uint64_t> &FoundFns,
uint64_t &BaseSegmentAddress) {
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();
bool BaseSegmentAddressSet = false;
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);
}
else if (Command.C.Type == macho::LCT_Segment) {
macho::SegmentLoadCommand SLC =
MachOObj->getSegmentLoadCommand(Command);
StringRef SegName = SLC.Name;
if(!BaseSegmentAddressSet && SegName != "__PAGEZERO") {
BaseSegmentAddressSet = true;
BaseSegmentAddress = SLC.VMAddress;
}
}
if (i == Header.NumLoadCommands - 1)
break;
else
Command = MachOObj->getNextLoadCommandInfo(Command);
}
}
static void DisassembleInputMachO2(StringRef Filename,
MachOObjectFile *MachOOF);
void llvm::DisassembleInputMachO(StringRef Filename) {
OwningPtr<MemoryBuffer> Buff;
if (error_code ec = MemoryBuffer::getFileOrSTDIN(Filename, Buff)) {
errs() << "llvm-objdump: " << Filename << ": " << ec.message() << "\n";
return;
}
OwningPtr<MachOObjectFile> MachOOF(static_cast<MachOObjectFile*>(
ObjectFile::createMachOObjectFile(Buff.take())));
DisassembleInputMachO2(Filename, MachOOF.get());
}
static void DisassembleInputMachO2(StringRef Filename,
MachOObjectFile *MachOOF) {
const Target *TheTarget = GetTarget(MachOOF);
if (!TheTarget) {
// GetTarget prints out stuff.
return;
}
OwningPtr<const MCInstrInfo> InstrInfo(TheTarget->createMCInstrInfo());
OwningPtr<MCInstrAnalysis>
InstrAnalysis(TheTarget->createMCInstrAnalysis(InstrInfo.get()));
// Set up disassembler.
OwningPtr<const MCRegisterInfo> MRI(TheTarget->createMCRegInfo(TripleName));
OwningPtr<const MCAsmInfo> AsmInfo(
TheTarget->createMCAsmInfo(*MRI, TripleName));
OwningPtr<const MCSubtargetInfo>
STI(TheTarget->createMCSubtargetInfo(TripleName, "", ""));
OwningPtr<const MCDisassembler> DisAsm(TheTarget->createMCDisassembler(*STI));
int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
OwningPtr<MCInstPrinter>
IP(TheTarget->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, *InstrInfo,
*MRI, *STI));
if (!InstrAnalysis || !AsmInfo || !STI || !DisAsm || !IP) {
errs() << "error: couldn't initialize disassembler for target "
<< TripleName << '\n';
return;
}
outs() << '\n' << Filename << ":\n\n";
macho::Header Header = MachOOF->getHeader();
// FIXME: FoundFns isn't used anymore. Using symbols/LC_FUNCTION_STARTS to
// determine function locations will eventually go in MCObjectDisassembler.
// FIXME: Using the -cfg command line option, this code used to be able to
// annotate relocations with the referenced symbol's name, and if this was
// inside a __[cf]string section, the data it points to. This is now replaced
// by the upcoming MCSymbolizer, which needs the appropriate setup done above.
std::vector<SectionRef> Sections;
std::vector<SymbolRef> Symbols;
SmallVector<uint64_t, 8> FoundFns;
uint64_t BaseSegmentAddress;
getSectionsAndSymbols(Header, MachOOF, Sections, Symbols, FoundFns,
BaseSegmentAddress);
// Make a copy of the unsorted symbol list. FIXME: duplication
std::vector<SymbolRef> UnsortedSymbols(Symbols);
// Sort the symbols by address, just in case they didn't come in that way.
std::sort(Symbols.begin(), Symbols.end(), SymbolSorter());
// Build a data in code table that is sorted on by the address of each entry.
uint64_t BaseAddress = 0;
if (Header.FileType == macho::HFT_Object)
Sections[0].getAddress(BaseAddress);
else
BaseAddress = BaseSegmentAddress;
DiceTable Dices;
error_code ec;
for (dice_iterator DI = MachOOF->begin_dices(), DE = MachOOF->end_dices();
DI != DE; DI.increment(ec)){
uint32_t Offset;
DI->getOffset(Offset);
Dices.push_back(std::make_pair(BaseAddress + Offset, *DI));
}
array_pod_sort(Dices.begin(), Dices.end());
#ifndef NDEBUG
raw_ostream &DebugOut = DebugFlag ? dbgs() : nulls();
#else
raw_ostream &DebugOut = nulls();
#endif
OwningPtr<DIContext> diContext;
ObjectFile *DbgObj = MachOOF;
// Try to find debug info and set up the DIContext for it.
if (UseDbg) {
// A separate DSym file path was specified, parse it as a macho file,
// get the sections and supply it to the section name parsing machinery.
if (!DSYMFile.empty()) {
OwningPtr<MemoryBuffer> Buf;
if (error_code ec = MemoryBuffer::getFileOrSTDIN(DSYMFile.c_str(), Buf)) {
errs() << "llvm-objdump: " << Filename << ": " << ec.message() << '\n';
return;
}
DbgObj = ObjectFile::createMachOObjectFile(Buf.take());
}
// Setup the DIContext
diContext.reset(DIContext::getDWARFContext(DbgObj));
}
for (unsigned SectIdx = 0; SectIdx != Sections.size(); SectIdx++) {
bool SectIsText = false;
Sections[SectIdx].isText(SectIsText);
if (SectIsText == false)
continue;
StringRef SectName;
if (Sections[SectIdx].getName(SectName) ||
SectName != "__text")
continue; // Skip non-text sections
DataRefImpl DR = Sections[SectIdx].getRawDataRefImpl();
StringRef SegmentName = MachOOF->getSectionFinalSegmentName(DR);
if (SegmentName != "__TEXT")
continue;
StringRef Bytes;
Sections[SectIdx].getContents(Bytes);
StringRefMemoryObject memoryObject(Bytes);
bool symbolTableWorked = false;
// Parse relocations.
std::vector<std::pair<uint64_t, SymbolRef> > Relocs;
error_code ec;
for (relocation_iterator RI = Sections[SectIdx].begin_relocations(),
RE = Sections[SectIdx].end_relocations(); RI != RE; RI.increment(ec)) {
uint64_t RelocOffset, SectionAddress;
RI->getOffset(RelocOffset);
Sections[SectIdx].getAddress(SectionAddress);
RelocOffset -= SectionAddress;
symbol_iterator RelocSym = RI->getSymbol();
Relocs.push_back(std::make_pair(RelocOffset, *RelocSym));
}
array_pod_sort(Relocs.begin(), Relocs.end());
// Disassemble symbol by symbol.
for (unsigned SymIdx = 0; SymIdx != Symbols.size(); SymIdx++) {
StringRef SymName;
Symbols[SymIdx].getName(SymName);
SymbolRef::Type ST;
Symbols[SymIdx].getType(ST);
if (ST != SymbolRef::ST_Function)
continue;
// Make sure the symbol is defined in this section.
bool containsSym = false;
Sections[SectIdx].containsSymbol(Symbols[SymIdx], containsSym);
if (!containsSym)
continue;
// Start at the address of the symbol relative to the section's address.
uint64_t SectionAddress = 0;
uint64_t Start = 0;
Sections[SectIdx].getAddress(SectionAddress);
Symbols[SymIdx].getAddress(Start);
Start -= SectionAddress;
// Stop disassembling either at the beginning of the next symbol or at
// the end of the section.
bool containsNextSym = false;
uint64_t NextSym = 0;
uint64_t NextSymIdx = SymIdx+1;
while (Symbols.size() > NextSymIdx) {
SymbolRef::Type NextSymType;
Symbols[NextSymIdx].getType(NextSymType);
if (NextSymType == SymbolRef::ST_Function) {
Sections[SectIdx].containsSymbol(Symbols[NextSymIdx],
containsNextSym);
Symbols[NextSymIdx].getAddress(NextSym);
NextSym -= SectionAddress;
break;
}
++NextSymIdx;
}
uint64_t SectSize;
Sections[SectIdx].getSize(SectSize);
uint64_t End = containsNextSym ? NextSym : SectSize;
uint64_t Size;
symbolTableWorked = true;
outs() << SymName << ":\n";
DILineInfo lastLine;
for (uint64_t Index = Start; Index < End; Index += Size) {
MCInst Inst;
uint64_t SectAddress = 0;
Sections[SectIdx].getAddress(SectAddress);
outs() << format("%8" PRIx64 ":\t", SectAddress + Index);
// Check the data in code table here to see if this is data not an
// instruction to be disassembled.
DiceTable Dice;
Dice.push_back(std::make_pair(SectAddress + Index, DiceRef()));
dice_table_iterator DTI = std::search(Dices.begin(), Dices.end(),
Dice.begin(), Dice.end(),
compareDiceTableEntries);
if (DTI != Dices.end()){
uint16_t Length;
DTI->second.getLength(Length);
DumpBytes(StringRef(Bytes.data() + Index, Length));
uint16_t Kind;
DTI->second.getKind(Kind);
DumpDataInCode(Bytes.data() + Index, Length, Kind);
continue;
}
if (DisAsm->getInstruction(Inst, Size, memoryObject, Index,
DebugOut, nulls())) {
DumpBytes(StringRef(Bytes.data() + Index, Size));
IP->printInst(&Inst, outs(), "");
// Print debug info.
if (diContext) {
DILineInfo dli =
diContext->getLineInfoForAddress(SectAddress + Index);
// Print valid line info if it changed.
if (dli != lastLine && dli.getLine() != 0)
outs() << "\t## " << dli.getFileName() << ':'
<< dli.getLine() << ':' << dli.getColumn();
lastLine = dli;
}
outs() << "\n";
} else {
errs() << "llvm-objdump: warning: invalid instruction encoding\n";
if (Size == 0)
Size = 1; // skip illegible bytes
}
}
}
if (!symbolTableWorked) {
// Reading the symbol table didn't work, disassemble the whole section.
uint64_t SectAddress;
Sections[SectIdx].getAddress(SectAddress);
uint64_t SectSize;
Sections[SectIdx].getSize(SectSize);
uint64_t InstSize;
for (uint64_t Index = 0; Index < SectSize; Index += InstSize) {
MCInst Inst;
if (DisAsm->getInstruction(Inst, InstSize, memoryObject, Index,
DebugOut, nulls())) {
outs() << format("%8" PRIx64 ":\t", SectAddress + Index);
DumpBytes(StringRef(Bytes.data() + Index, InstSize));
IP->printInst(&Inst, outs(), "");
outs() << "\n";
} else {
errs() << "llvm-objdump: warning: invalid instruction encoding\n";
if (InstSize == 0)
InstSize = 1; // skip illegible bytes
}
}
}
}
}