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