1//===-- llvm-objdump.cpp - Object file dumping utility for llvm -----------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This program is a utility that works like binutils "objdump", that is, it
11// dumps out a plethora of information about an object file depending on the
12// flags.
13//
14//===----------------------------------------------------------------------===//
15
16#include "llvm-objdump.h"
17#include "MCFunction.h"
18#include "llvm/Object/Archive.h"
19#include "llvm/Object/COFF.h"
20#include "llvm/Object/ObjectFile.h"
21#include "llvm/ADT/OwningPtr.h"
22#include "llvm/ADT/StringExtras.h"
23#include "llvm/ADT/Triple.h"
24#include "llvm/ADT/STLExtras.h"
25#include "llvm/MC/MCAsmInfo.h"
26#include "llvm/MC/MCDisassembler.h"
27#include "llvm/MC/MCInst.h"
28#include "llvm/MC/MCInstPrinter.h"
29#include "llvm/MC/MCInstrInfo.h"
30#include "llvm/MC/MCRegisterInfo.h"
31#include "llvm/MC/MCSubtargetInfo.h"
32#include "llvm/Support/Casting.h"
33#include "llvm/Support/CommandLine.h"
34#include "llvm/Support/Debug.h"
35#include "llvm/Support/FileSystem.h"
36#include "llvm/Support/Format.h"
37#include "llvm/Support/GraphWriter.h"
38#include "llvm/Support/Host.h"
39#include "llvm/Support/ManagedStatic.h"
40#include "llvm/Support/MemoryBuffer.h"
41#include "llvm/Support/MemoryObject.h"
42#include "llvm/Support/PrettyStackTrace.h"
43#include "llvm/Support/Signals.h"
44#include "llvm/Support/SourceMgr.h"
45#include "llvm/Support/TargetRegistry.h"
46#include "llvm/Support/TargetSelect.h"
47#include "llvm/Support/raw_ostream.h"
48#include "llvm/Support/system_error.h"
49#include <algorithm>
50#include <cctype>
51#include <cstring>
52using namespace llvm;
53using namespace object;
54
55static cl::list<std::string>
56InputFilenames(cl::Positional, cl::desc("<input object files>"),cl::ZeroOrMore);
57
58static cl::opt<bool>
59Disassemble("disassemble",
60  cl::desc("Display assembler mnemonics for the machine instructions"));
61static cl::alias
62Disassembled("d", cl::desc("Alias for --disassemble"),
63             cl::aliasopt(Disassemble));
64
65static cl::opt<bool>
66Relocations("r", cl::desc("Display the relocation entries in the file"));
67
68static cl::opt<bool>
69SectionContents("s", cl::desc("Display the content of each section"));
70
71static cl::opt<bool>
72SymbolTable("t", cl::desc("Display the symbol table"));
73
74static cl::opt<bool>
75MachO("macho", cl::desc("Use MachO specific object file parser"));
76static cl::alias
77MachOm("m", cl::desc("Alias for --macho"), cl::aliasopt(MachO));
78
79cl::opt<std::string>
80llvm::TripleName("triple", cl::desc("Target triple to disassemble for, "
81                                    "see -version for available targets"));
82
83cl::opt<std::string>
84llvm::ArchName("arch", cl::desc("Target arch to disassemble for, "
85                                "see -version for available targets"));
86
87static cl::opt<bool>
88SectionHeaders("section-headers", cl::desc("Display summaries of the headers "
89                                           "for each section."));
90static cl::alias
91SectionHeadersShort("headers", cl::desc("Alias for --section-headers"),
92                    cl::aliasopt(SectionHeaders));
93static cl::alias
94SectionHeadersShorter("h", cl::desc("Alias for --section-headers"),
95                      cl::aliasopt(SectionHeaders));
96
97static cl::list<std::string>
98MAttrs("mattr",
99  cl::CommaSeparated,
100  cl::desc("Target specific attributes"),
101  cl::value_desc("a1,+a2,-a3,..."));
102
103static StringRef ToolName;
104
105static bool error(error_code ec) {
106  if (!ec) return false;
107
108  outs() << ToolName << ": error reading file: " << ec.message() << ".\n";
109  outs().flush();
110  return true;
111}
112
113static const Target *getTarget(const ObjectFile *Obj = NULL) {
114  // Figure out the target triple.
115  llvm::Triple TheTriple("unknown-unknown-unknown");
116  if (TripleName.empty()) {
117    if (Obj)
118      TheTriple.setArch(Triple::ArchType(Obj->getArch()));
119  } else
120    TheTriple.setTriple(Triple::normalize(TripleName));
121
122  // Get the target specific parser.
123  std::string Error;
124  const Target *TheTarget = TargetRegistry::lookupTarget(ArchName, TheTriple,
125                                                         Error);
126  if (!TheTarget) {
127    errs() << ToolName << ": " << Error;
128    return 0;
129  }
130
131  // Update the triple name and return the found target.
132  TripleName = TheTriple.getTriple();
133  return TheTarget;
134}
135
136void llvm::StringRefMemoryObject::anchor() { }
137
138void llvm::DumpBytes(StringRef bytes) {
139  static const char hex_rep[] = "0123456789abcdef";
140  // FIXME: The real way to do this is to figure out the longest instruction
141  //        and align to that size before printing. I'll fix this when I get
142  //        around to outputting relocations.
143  // 15 is the longest x86 instruction
144  // 3 is for the hex rep of a byte + a space.
145  // 1 is for the null terminator.
146  enum { OutputSize = (15 * 3) + 1 };
147  char output[OutputSize];
148
149  assert(bytes.size() <= 15
150    && "DumpBytes only supports instructions of up to 15 bytes");
151  memset(output, ' ', sizeof(output));
152  unsigned index = 0;
153  for (StringRef::iterator i = bytes.begin(),
154                           e = bytes.end(); i != e; ++i) {
155    output[index] = hex_rep[(*i & 0xF0) >> 4];
156    output[index + 1] = hex_rep[*i & 0xF];
157    index += 3;
158  }
159
160  output[sizeof(output) - 1] = 0;
161  outs() << output;
162}
163
164static bool RelocAddressLess(RelocationRef a, RelocationRef b) {
165  uint64_t a_addr, b_addr;
166  if (error(a.getAddress(a_addr))) return false;
167  if (error(b.getAddress(b_addr))) return false;
168  return a_addr < b_addr;
169}
170
171static void DisassembleObject(const ObjectFile *Obj, bool InlineRelocs) {
172  const Target *TheTarget = getTarget(Obj);
173  // getTarget() will have already issued a diagnostic if necessary, so
174  // just bail here if it failed.
175  if (!TheTarget)
176    return;
177
178  // Package up features to be passed to target/subtarget
179  std::string FeaturesStr;
180  if (MAttrs.size()) {
181    SubtargetFeatures Features;
182    for (unsigned i = 0; i != MAttrs.size(); ++i)
183      Features.AddFeature(MAttrs[i]);
184    FeaturesStr = Features.getString();
185  }
186
187  error_code ec;
188  for (section_iterator i = Obj->begin_sections(),
189                        e = Obj->end_sections();
190                        i != e; i.increment(ec)) {
191    if (error(ec)) break;
192    bool text;
193    if (error(i->isText(text))) break;
194    if (!text) continue;
195
196    uint64_t SectionAddr;
197    if (error(i->getAddress(SectionAddr))) break;
198
199    // Make a list of all the symbols in this section.
200    std::vector<std::pair<uint64_t, StringRef> > Symbols;
201    for (symbol_iterator si = Obj->begin_symbols(),
202                         se = Obj->end_symbols();
203                         si != se; si.increment(ec)) {
204      bool contains;
205      if (!error(i->containsSymbol(*si, contains)) && contains) {
206        uint64_t Address;
207        if (error(si->getAddress(Address))) break;
208        Address -= SectionAddr;
209
210        StringRef Name;
211        if (error(si->getName(Name))) break;
212        Symbols.push_back(std::make_pair(Address, Name));
213      }
214    }
215
216    // Sort the symbols by address, just in case they didn't come in that way.
217    array_pod_sort(Symbols.begin(), Symbols.end());
218
219    // Make a list of all the relocations for this section.
220    std::vector<RelocationRef> Rels;
221    if (InlineRelocs) {
222      for (relocation_iterator ri = i->begin_relocations(),
223                               re = i->end_relocations();
224                               ri != re; ri.increment(ec)) {
225        if (error(ec)) break;
226        Rels.push_back(*ri);
227      }
228    }
229
230    // Sort relocations by address.
231    std::sort(Rels.begin(), Rels.end(), RelocAddressLess);
232
233    StringRef name;
234    if (error(i->getName(name))) break;
235    outs() << "Disassembly of section " << name << ':';
236
237    // If the section has no symbols just insert a dummy one and disassemble
238    // the whole section.
239    if (Symbols.empty())
240      Symbols.push_back(std::make_pair(0, name));
241
242    // Set up disassembler.
243    OwningPtr<const MCAsmInfo> AsmInfo(TheTarget->createMCAsmInfo(TripleName));
244
245    if (!AsmInfo) {
246      errs() << "error: no assembly info for target " << TripleName << "\n";
247      return;
248    }
249
250    OwningPtr<const MCSubtargetInfo> STI(
251      TheTarget->createMCSubtargetInfo(TripleName, "", FeaturesStr));
252
253    if (!STI) {
254      errs() << "error: no subtarget info for target " << TripleName << "\n";
255      return;
256    }
257
258    OwningPtr<const MCDisassembler> DisAsm(
259      TheTarget->createMCDisassembler(*STI));
260    if (!DisAsm) {
261      errs() << "error: no disassembler for target " << TripleName << "\n";
262      return;
263    }
264
265    OwningPtr<const MCRegisterInfo> MRI(TheTarget->createMCRegInfo(TripleName));
266    if (!MRI) {
267      errs() << "error: no register info for target " << TripleName << "\n";
268      return;
269    }
270
271    OwningPtr<const MCInstrInfo> MII(TheTarget->createMCInstrInfo());
272    if (!MII) {
273      errs() << "error: no instruction info for target " << TripleName << "\n";
274      return;
275    }
276
277    int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
278    OwningPtr<MCInstPrinter> IP(TheTarget->createMCInstPrinter(
279                                AsmPrinterVariant, *AsmInfo, *MII, *MRI, *STI));
280    if (!IP) {
281      errs() << "error: no instruction printer for target " << TripleName
282             << '\n';
283      return;
284    }
285
286    StringRef Bytes;
287    if (error(i->getContents(Bytes))) break;
288    StringRefMemoryObject memoryObject(Bytes);
289    uint64_t Size;
290    uint64_t Index;
291    uint64_t SectSize;
292    if (error(i->getSize(SectSize))) break;
293
294    std::vector<RelocationRef>::const_iterator rel_cur = Rels.begin();
295    std::vector<RelocationRef>::const_iterator rel_end = Rels.end();
296    // Disassemble symbol by symbol.
297    for (unsigned si = 0, se = Symbols.size(); si != se; ++si) {
298      uint64_t Start = Symbols[si].first;
299      uint64_t End;
300      // The end is either the size of the section or the beginning of the next
301      // symbol.
302      if (si == se - 1)
303        End = SectSize;
304      // Make sure this symbol takes up space.
305      else if (Symbols[si + 1].first != Start)
306        End = Symbols[si + 1].first - 1;
307      else
308        // This symbol has the same address as the next symbol. Skip it.
309        continue;
310
311      outs() << '\n' << Symbols[si].second << ":\n";
312
313#ifndef NDEBUG
314        raw_ostream &DebugOut = DebugFlag ? dbgs() : nulls();
315#else
316        raw_ostream &DebugOut = nulls();
317#endif
318
319      for (Index = Start; Index < End; Index += Size) {
320        MCInst Inst;
321
322        if (DisAsm->getInstruction(Inst, Size, memoryObject, Index,
323                                   DebugOut, nulls())) {
324          outs() << format("%8" PRIx64 ":\t", SectionAddr + Index);
325          DumpBytes(StringRef(Bytes.data() + Index, Size));
326          IP->printInst(&Inst, outs(), "");
327          outs() << "\n";
328        } else {
329          errs() << ToolName << ": warning: invalid instruction encoding\n";
330          if (Size == 0)
331            Size = 1; // skip illegible bytes
332        }
333
334        // Print relocation for instruction.
335        while (rel_cur != rel_end) {
336          bool hidden = false;
337          uint64_t addr;
338          SmallString<16> name;
339          SmallString<32> val;
340
341          // If this relocation is hidden, skip it.
342          if (error(rel_cur->getHidden(hidden))) goto skip_print_rel;
343          if (hidden) goto skip_print_rel;
344
345          if (error(rel_cur->getAddress(addr))) goto skip_print_rel;
346          // Stop when rel_cur's address is past the current instruction.
347          if (addr >= Index + Size) break;
348          if (error(rel_cur->getTypeName(name))) goto skip_print_rel;
349          if (error(rel_cur->getValueString(val))) goto skip_print_rel;
350
351          outs() << format("\t\t\t%8" PRIx64 ": ", SectionAddr + addr) << name
352                 << "\t" << val << "\n";
353
354        skip_print_rel:
355          ++rel_cur;
356        }
357      }
358    }
359  }
360}
361
362static void PrintRelocations(const ObjectFile *o) {
363  error_code ec;
364  for (section_iterator si = o->begin_sections(), se = o->end_sections();
365                                                  si != se; si.increment(ec)){
366    if (error(ec)) return;
367    if (si->begin_relocations() == si->end_relocations())
368      continue;
369    StringRef secname;
370    if (error(si->getName(secname))) continue;
371    outs() << "RELOCATION RECORDS FOR [" << secname << "]:\n";
372    for (relocation_iterator ri = si->begin_relocations(),
373                             re = si->end_relocations();
374                             ri != re; ri.increment(ec)) {
375      if (error(ec)) return;
376
377      bool hidden;
378      uint64_t address;
379      SmallString<32> relocname;
380      SmallString<32> valuestr;
381      if (error(ri->getHidden(hidden))) continue;
382      if (hidden) continue;
383      if (error(ri->getTypeName(relocname))) continue;
384      if (error(ri->getAddress(address))) continue;
385      if (error(ri->getValueString(valuestr))) continue;
386      outs() << address << " " << relocname << " " << valuestr << "\n";
387    }
388    outs() << "\n";
389  }
390}
391
392static void PrintSectionHeaders(const ObjectFile *o) {
393  outs() << "Sections:\n"
394            "Idx Name          Size      Address          Type\n";
395  error_code ec;
396  unsigned i = 0;
397  for (section_iterator si = o->begin_sections(), se = o->end_sections();
398                                                  si != se; si.increment(ec)) {
399    if (error(ec)) return;
400    StringRef Name;
401    if (error(si->getName(Name))) return;
402    uint64_t Address;
403    if (error(si->getAddress(Address))) return;
404    uint64_t Size;
405    if (error(si->getSize(Size))) return;
406    bool Text, Data, BSS;
407    if (error(si->isText(Text))) return;
408    if (error(si->isData(Data))) return;
409    if (error(si->isBSS(BSS))) return;
410    std::string Type = (std::string(Text ? "TEXT " : "") +
411                        (Data ? "DATA " : "") + (BSS ? "BSS" : ""));
412    outs() << format("%3d %-13s %09" PRIx64 " %017" PRIx64 " %s\n",
413                     i, Name.str().c_str(), Size, Address, Type.c_str());
414    ++i;
415  }
416}
417
418static void PrintSectionContents(const ObjectFile *o) {
419  error_code ec;
420  for (section_iterator si = o->begin_sections(),
421                        se = o->end_sections();
422                        si != se; si.increment(ec)) {
423    if (error(ec)) return;
424    StringRef Name;
425    StringRef Contents;
426    uint64_t BaseAddr;
427    if (error(si->getName(Name))) continue;
428    if (error(si->getContents(Contents))) continue;
429    if (error(si->getAddress(BaseAddr))) continue;
430
431    outs() << "Contents of section " << Name << ":\n";
432
433    // Dump out the content as hex and printable ascii characters.
434    for (std::size_t addr = 0, end = Contents.size(); addr < end; addr += 16) {
435      outs() << format(" %04" PRIx64 " ", BaseAddr + addr);
436      // Dump line of hex.
437      for (std::size_t i = 0; i < 16; ++i) {
438        if (i != 0 && i % 4 == 0)
439          outs() << ' ';
440        if (addr + i < end)
441          outs() << hexdigit((Contents[addr + i] >> 4) & 0xF, true)
442                 << hexdigit(Contents[addr + i] & 0xF, true);
443        else
444          outs() << "  ";
445      }
446      // Print ascii.
447      outs() << "  ";
448      for (std::size_t i = 0; i < 16 && addr + i < end; ++i) {
449        if (std::isprint(Contents[addr + i] & 0xFF))
450          outs() << Contents[addr + i];
451        else
452          outs() << ".";
453      }
454      outs() << "\n";
455    }
456  }
457}
458
459static void PrintCOFFSymbolTable(const COFFObjectFile *coff) {
460  const coff_file_header *header;
461  if (error(coff->getHeader(header))) return;
462  int aux_count = 0;
463  const coff_symbol *symbol = 0;
464  for (int i = 0, e = header->NumberOfSymbols; i != e; ++i) {
465    if (aux_count--) {
466      // Figure out which type of aux this is.
467      if (symbol->StorageClass == COFF::IMAGE_SYM_CLASS_STATIC
468          && symbol->Value == 0) { // Section definition.
469        const coff_aux_section_definition *asd;
470        if (error(coff->getAuxSymbol<coff_aux_section_definition>(i, asd)))
471          return;
472        outs() << "AUX "
473               << format("scnlen 0x%x nreloc %d nlnno %d checksum 0x%x "
474                         , unsigned(asd->Length)
475                         , unsigned(asd->NumberOfRelocations)
476                         , unsigned(asd->NumberOfLinenumbers)
477                         , unsigned(asd->CheckSum))
478               << format("assoc %d comdat %d\n"
479                         , unsigned(asd->Number)
480                         , unsigned(asd->Selection));
481      } else
482        outs() << "AUX Unknown\n";
483    } else {
484      StringRef name;
485      if (error(coff->getSymbol(i, symbol))) return;
486      if (error(coff->getSymbolName(symbol, name))) return;
487      outs() << "[" << format("%2d", i) << "]"
488             << "(sec " << format("%2d", int(symbol->SectionNumber)) << ")"
489             << "(fl 0x00)" // Flag bits, which COFF doesn't have.
490             << "(ty " << format("%3x", unsigned(symbol->Type)) << ")"
491             << "(scl " << format("%3x", unsigned(symbol->StorageClass)) << ") "
492             << "(nx " << unsigned(symbol->NumberOfAuxSymbols) << ") "
493             << "0x" << format("%08x", unsigned(symbol->Value)) << " "
494             << name << "\n";
495      aux_count = symbol->NumberOfAuxSymbols;
496    }
497  }
498}
499
500static void PrintSymbolTable(const ObjectFile *o) {
501  outs() << "SYMBOL TABLE:\n";
502
503  if (const COFFObjectFile *coff = dyn_cast<const COFFObjectFile>(o))
504    PrintCOFFSymbolTable(coff);
505  else {
506    error_code ec;
507    for (symbol_iterator si = o->begin_symbols(),
508                         se = o->end_symbols(); si != se; si.increment(ec)) {
509      if (error(ec)) return;
510      StringRef Name;
511      uint64_t Address;
512      SymbolRef::Type Type;
513      uint64_t Size;
514      uint32_t Flags;
515      section_iterator Section = o->end_sections();
516      if (error(si->getName(Name))) continue;
517      if (error(si->getAddress(Address))) continue;
518      if (error(si->getFlags(Flags))) continue;
519      if (error(si->getType(Type))) continue;
520      if (error(si->getSize(Size))) continue;
521      if (error(si->getSection(Section))) continue;
522
523      bool Global = Flags & SymbolRef::SF_Global;
524      bool Weak = Flags & SymbolRef::SF_Weak;
525      bool Absolute = Flags & SymbolRef::SF_Absolute;
526
527      if (Address == UnknownAddressOrSize)
528        Address = 0;
529      if (Size == UnknownAddressOrSize)
530        Size = 0;
531      char GlobLoc = ' ';
532      if (Type != SymbolRef::ST_Unknown)
533        GlobLoc = Global ? 'g' : 'l';
534      char Debug = (Type == SymbolRef::ST_Debug || Type == SymbolRef::ST_File)
535                   ? 'd' : ' ';
536      char FileFunc = ' ';
537      if (Type == SymbolRef::ST_File)
538        FileFunc = 'f';
539      else if (Type == SymbolRef::ST_Function)
540        FileFunc = 'F';
541
542      outs() << format("%08" PRIx64, Address) << " "
543             << GlobLoc // Local -> 'l', Global -> 'g', Neither -> ' '
544             << (Weak ? 'w' : ' ') // Weak?
545             << ' ' // Constructor. Not supported yet.
546             << ' ' // Warning. Not supported yet.
547             << ' ' // Indirect reference to another symbol.
548             << Debug // Debugging (d) or dynamic (D) symbol.
549             << FileFunc // Name of function (F), file (f) or object (O).
550             << ' ';
551      if (Absolute)
552        outs() << "*ABS*";
553      else if (Section == o->end_sections())
554        outs() << "*UND*";
555      else {
556        StringRef SectionName;
557        if (error(Section->getName(SectionName)))
558          SectionName = "";
559        outs() << SectionName;
560      }
561      outs() << '\t'
562             << format("%08" PRIx64 " ", Size)
563             << Name
564             << '\n';
565    }
566  }
567}
568
569static void DumpObject(const ObjectFile *o) {
570  outs() << '\n';
571  outs() << o->getFileName()
572         << ":\tfile format " << o->getFileFormatName() << "\n\n";
573
574  if (Disassemble)
575    DisassembleObject(o, Relocations);
576  if (Relocations && !Disassemble)
577    PrintRelocations(o);
578  if (SectionHeaders)
579    PrintSectionHeaders(o);
580  if (SectionContents)
581    PrintSectionContents(o);
582  if (SymbolTable)
583    PrintSymbolTable(o);
584}
585
586/// @brief Dump each object file in \a a;
587static void DumpArchive(const Archive *a) {
588  for (Archive::child_iterator i = a->begin_children(),
589                               e = a->end_children(); i != e; ++i) {
590    OwningPtr<Binary> child;
591    if (error_code ec = i->getAsBinary(child)) {
592      // Ignore non-object files.
593      if (ec != object_error::invalid_file_type)
594        errs() << ToolName << ": '" << a->getFileName() << "': " << ec.message()
595               << ".\n";
596      continue;
597    }
598    if (ObjectFile *o = dyn_cast<ObjectFile>(child.get()))
599      DumpObject(o);
600    else
601      errs() << ToolName << ": '" << a->getFileName() << "': "
602              << "Unrecognized file type.\n";
603  }
604}
605
606/// @brief Open file and figure out how to dump it.
607static void DumpInput(StringRef file) {
608  // If file isn't stdin, check that it exists.
609  if (file != "-" && !sys::fs::exists(file)) {
610    errs() << ToolName << ": '" << file << "': " << "No such file\n";
611    return;
612  }
613
614  if (MachO && Disassemble) {
615    DisassembleInputMachO(file);
616    return;
617  }
618
619  // Attempt to open the binary.
620  OwningPtr<Binary> binary;
621  if (error_code ec = createBinary(file, binary)) {
622    errs() << ToolName << ": '" << file << "': " << ec.message() << ".\n";
623    return;
624  }
625
626  if (Archive *a = dyn_cast<Archive>(binary.get()))
627    DumpArchive(a);
628  else if (ObjectFile *o = dyn_cast<ObjectFile>(binary.get()))
629    DumpObject(o);
630  else
631    errs() << ToolName << ": '" << file << "': " << "Unrecognized file type.\n";
632}
633
634int main(int argc, char **argv) {
635  // Print a stack trace if we signal out.
636  sys::PrintStackTraceOnErrorSignal();
637  PrettyStackTraceProgram X(argc, argv);
638  llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
639
640  // Initialize targets and assembly printers/parsers.
641  llvm::InitializeAllTargetInfos();
642  llvm::InitializeAllTargetMCs();
643  llvm::InitializeAllAsmParsers();
644  llvm::InitializeAllDisassemblers();
645
646  // Register the target printer for --version.
647  cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
648
649  cl::ParseCommandLineOptions(argc, argv, "llvm object file dumper\n");
650  TripleName = Triple::normalize(TripleName);
651
652  ToolName = argv[0];
653
654  // Defaults to a.out if no filenames specified.
655  if (InputFilenames.size() == 0)
656    InputFilenames.push_back("a.out");
657
658  if (!Disassemble
659      && !Relocations
660      && !SectionHeaders
661      && !SectionContents
662      && !SymbolTable) {
663    cl::PrintHelpMessage();
664    return 2;
665  }
666
667  std::for_each(InputFilenames.begin(), InputFilenames.end(),
668                DumpInput);
669
670  return 0;
671}
672