tools/llvm-objdump/MachODump.cpp

   1 //===-- MachODump.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 file implements the MachO-specific dumper for llvm-objdump.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm-objdump.h"
  15 #include "MCFunction.h"
  16 #include "llvm/Support/MachO.h"
  17 #include "llvm/Object/MachOObject.h"
  18 #include "llvm/ADT/OwningPtr.h"
  19 #include "llvm/ADT/Triple.h"
  20 #include "llvm/ADT/STLExtras.h"
  21 #include "llvm/DebugInfo/DIContext.h"
  22 #include "llvm/MC/MCAsmInfo.h"
  23 #include "llvm/MC/MCDisassembler.h"
  24 #include "llvm/MC/MCInst.h"
  25 #include "llvm/MC/MCInstPrinter.h"
  26 #include "llvm/MC/MCInstrAnalysis.h"
  27 #include "llvm/MC/MCInstrDesc.h"
  28 #include "llvm/MC/MCInstrInfo.h"
  29 #include "llvm/MC/MCSubtargetInfo.h"
  30 #include "llvm/Support/CommandLine.h"
  31 #include "llvm/Support/Debug.h"
  32 #include "llvm/Support/Format.h"
  33 #include "llvm/Support/GraphWriter.h"
  34 #include "llvm/Support/MemoryBuffer.h"
  35 #include "llvm/Support/TargetRegistry.h"
  36 #include "llvm/Support/TargetSelect.h"
  37 #include "llvm/Support/raw_ostream.h"
  38 #include "llvm/Support/system_error.h"
  39 #include <algorithm>
  40 #include <cstring>
  41 using namespace llvm;
  42 using namespace object;
  43
  44 static cl::opt<bool>
  45   CFG("cfg", cl::desc("Create a CFG for every symbol in the object file and"
  46                       "write it to a graphviz file (MachO-only)"));
  47
  48 static cl::opt<bool>
  49   UseDbg("g", cl::desc("Print line information from debug info if available"));
  50
  51 static cl::opt<std::string>
  52   DSYMFile("dsym", cl::desc("Use .dSYM file for debug info"));
  53
  54 static const Target *GetTarget(const MachOObject *MachOObj) {
  55   // Figure out the target triple.
  56   llvm::Triple TT("unknown-unknown-unknown");
  57   switch (MachOObj->getHeader().CPUType) {
  58   case llvm::MachO::CPUTypeI386:
  59     TT.setArch(Triple::ArchType(Triple::x86));
  60     break;
  61   case llvm::MachO::CPUTypeX86_64:
  62     TT.setArch(Triple::ArchType(Triple::x86_64));
  63     break;
  64   case llvm::MachO::CPUTypeARM:
  65     TT.setArch(Triple::ArchType(Triple::arm));
  66     break;
  67   case llvm::MachO::CPUTypePowerPC:
  68     TT.setArch(Triple::ArchType(Triple::ppc));
  69     break;
  70   case llvm::MachO::CPUTypePowerPC64:
  71     TT.setArch(Triple::ArchType(Triple::ppc64));
  72     break;
  73   }
  74
  75   TripleName = TT.str();
  76
  77   // Get the target specific parser.
  78   std::string Error;
  79   const Target *TheTarget = TargetRegistry::lookupTarget(TripleName, Error);
  80   if (TheTarget)
  81     return TheTarget;
  82
  83   errs() << "llvm-objdump: error: unable to get target for '" << TripleName
  84          << "', see --version and --triple.\n";
  85   return 0;
  86 }
  87
  88 struct Section {
  89   char Name[16];
  90   uint64_t Address;
  91   uint64_t Size;
  92   uint32_t Offset;
  93   uint32_t NumRelocs;
  94   uint64_t RelocTableOffset;
  95 };
  96
  97 struct Symbol {
  98   uint64_t Value;
  99   uint32_t StringIndex;
 100   uint8_t SectionIndex;
 101   bool operator<(const Symbol &RHS) const { return Value < RHS.Value; }
 102 };
 103
 104 template <typename T>
 105 static Section copySection(const T &Sect) {
 106   Section S;
 107   memcpy(S.Name, Sect->Name, 16);
 108   S.Address = Sect->Address;
 109   S.Size = Sect->Size;
 110   S.Offset = Sect->Offset;
 111   S.NumRelocs = Sect->NumRelocationTableEntries;
 112   S.RelocTableOffset = Sect->RelocationTableOffset;
 113   return S;
 114 }
 115
 116 template <typename T>
 117 static Symbol copySymbol(const T &STE) {
 118   Symbol S;
 119   S.StringIndex = STE->StringIndex;
 120   S.SectionIndex = STE->SectionIndex;
 121   S.Value = STE->Value;
 122   return S;
 123 }
 124
 125 // Print additional information about an address, if available.
 126 static void DumpAddress(uint64_t Address, ArrayRef<Section> Sections,
 127                         MachOObject *MachOObj, raw_ostream &OS) {
 128   for (unsigned i = 0; i != Sections.size(); ++i) {
 129     uint64_t addr = Address-Sections[i].Address;
 130     if (Sections[i].Address <= Address &&
 131         Sections[i].Address + Sections[i].Size > Address) {
 132       StringRef bytes = MachOObj->getData(Sections[i].Offset,
 133                                           Sections[i].Size);
 134       // Print constant strings.
 135       if (!strcmp(Sections[i].Name, "__cstring"))
 136         OS << '"' << bytes.substr(addr, bytes.find('\0', addr)) << '"';
 137       // Print constant CFStrings.
 138       if (!strcmp(Sections[i].Name, "__cfstring"))
 139         OS << "@\"" << bytes.substr(addr, bytes.find('\0', addr)) << '"';
 140     }
 141   }
 142 }
 143
 144 typedef std::map<uint64_t, MCFunction*> FunctionMapTy;
 145 typedef SmallVector<MCFunction, 16> FunctionListTy;
 146 static void createMCFunctionAndSaveCalls(StringRef Name,
 147                                          const MCDisassembler *DisAsm,
 148                                          MemoryObject &Object, uint64_t Start,
 149                                          uint64_t End,
 150                                          MCInstrAnalysis *InstrAnalysis,
 151                                          uint64_t Address,
 152                                          raw_ostream &DebugOut,
 153                                          FunctionMapTy &FunctionMap,
 154                                          FunctionListTy &Functions) {
 155   SmallVector<uint64_t, 16> Calls;
 156   MCFunction f =
 157     MCFunction::createFunctionFromMC(Name, DisAsm, Object, Start, End,
 158                                      InstrAnalysis, DebugOut, Calls);
 159   Functions.push_back(f);
 160   FunctionMap[Address] = &Functions.back();
 161
 162   // Add the gathered callees to the map.
 163   for (unsigned i = 0, e = Calls.size(); i != e; ++i)
 164     FunctionMap.insert(std::make_pair(Calls[i], (MCFunction*)0));
 165 }
 166
 167 // Write a graphviz file for the CFG inside an MCFunction.
 168 static void emitDOTFile(const char *FileName, const MCFunction &f,
 169                         MCInstPrinter *IP) {
 170   // Start a new dot file.
 171   std::string Error;
 172   raw_fd_ostream Out(FileName, Error);
 173   if (!Error.empty()) {
 174     errs() << "llvm-objdump: warning: " << Error << '\n';
 175     return;
 176   }
 177
 178   Out << "digraph " << f.getName() << " {\n";
 179   Out << "graph [ rankdir = \"LR\" ];\n";
 180   for (MCFunction::iterator i = f.begin(), e = f.end(); i != e; ++i) {
 181     bool hasPreds = false;
 182     // Only print blocks that have predecessors.
 183     // FIXME: Slow.
 184     for (MCFunction::iterator pi = f.begin(), pe = f.end(); pi != pe;
 185         ++pi)
 186       if (pi->second.contains(i->first)) {
 187         hasPreds = true;
 188         break;
 189       }
 190
 191     if (!hasPreds && i != f.begin())
 192       continue;
 193
 194     Out << '"' << i->first << "\" [ label=\"<a>";
 195     // Print instructions.
 196     for (unsigned ii = 0, ie = i->second.getInsts().size(); ii != ie;
 197         ++ii) {
 198       // Escape special chars and print the instruction in mnemonic form.
 199       std::string Str;
 200       raw_string_ostream OS(Str);
 201       IP->printInst(&i->second.getInsts()[ii].Inst, OS, "");
 202       Out << DOT::EscapeString(OS.str()) << '|';
 203     }
 204     Out << "<o>\" shape=\"record\" ];\n";
 205
 206     // Add edges.
 207     for (MCBasicBlock::succ_iterator si = i->second.succ_begin(),
 208         se = i->second.succ_end(); si != se; ++si)
 209       Out << i->first << ":o -> " << *si <<":a\n";
 210   }
 211   Out << "}\n";
 212 }
 213
 214 static void getSectionsAndSymbols(const macho::Header &Header,
 215                                   MachOObject *MachOObj,
 216                              InMemoryStruct<macho::SymtabLoadCommand> *SymtabLC,
 217                                   std::vector<Section> &Sections,
 218                                   std::vector<Symbol> &Symbols,
 219                                   SmallVectorImpl<uint64_t> &FoundFns) {
 220   // Make a list of all symbols in the object file.
 221   for (unsigned i = 0; i != Header.NumLoadCommands; ++i) {
 222     const MachOObject::LoadCommandInfo &LCI = MachOObj->getLoadCommandInfo(i);
 223     if (LCI.Command.Type == macho::LCT_Segment) {
 224       InMemoryStruct<macho::SegmentLoadCommand> SegmentLC;
 225       MachOObj->ReadSegmentLoadCommand(LCI, SegmentLC);
 226
 227       // Store the sections in this segment.
 228       for (unsigned SectNum = 0; SectNum != SegmentLC->NumSections; ++SectNum) {
 229         InMemoryStruct<macho::Section> Sect;
 230         MachOObj->ReadSection(LCI, SectNum, Sect);
 231         Sections.push_back(copySection(Sect));
 232
 233       }
 234     } else if (LCI.Command.Type == macho::LCT_Segment64) {
 235       InMemoryStruct<macho::Segment64LoadCommand> Segment64LC;
 236       MachOObj->ReadSegment64LoadCommand(LCI, Segment64LC);
 237
 238       // Store the sections in this segment.
 239       for (unsigned SectNum = 0; SectNum != Segment64LC->NumSections;
 240           ++SectNum) {
 241         InMemoryStruct<macho::Section64> Sect64;
 242         MachOObj->ReadSection64(LCI, SectNum, Sect64);
 243         Sections.push_back(copySection(Sect64));
 244       }
 245     } else if (LCI.Command.Type == macho::LCT_FunctionStarts) {
 246       // We found a function starts segment, parse the addresses for later
 247       // consumption.
 248       InMemoryStruct<macho::LinkeditDataLoadCommand> LLC;
 249       MachOObj->ReadLinkeditDataLoadCommand(LCI, LLC);
 250
 251       MachOObj->ReadULEB128s(LLC->DataOffset, FoundFns);
 252     }
 253   }
 254   // Store the symbols.
 255   if (SymtabLC) {
 256     for (unsigned i = 0; i != (*SymtabLC)->NumSymbolTableEntries; ++i) {
 257       if (MachOObj->is64Bit()) {
 258         InMemoryStruct<macho::Symbol64TableEntry> STE;
 259         MachOObj->ReadSymbol64TableEntry((*SymtabLC)->SymbolTableOffset, i,
 260                                          STE);
 261         Symbols.push_back(copySymbol(STE));
 262       } else {
 263         InMemoryStruct<macho::SymbolTableEntry> STE;
 264         MachOObj->ReadSymbolTableEntry((*SymtabLC)->SymbolTableOffset, i,
 265                                        STE);
 266         Symbols.push_back(copySymbol(STE));
 267       }
 268     }
 269   }
 270 }
 271
 272 void llvm::DisassembleInputMachO(StringRef Filename) {
 273   OwningPtr<MemoryBuffer> Buff;
 274
 275   if (error_code ec = MemoryBuffer::getFileOrSTDIN(Filename, Buff)) {
 276     errs() << "llvm-objdump: " << Filename << ": " << ec.message() << "\n";
 277     return;
 278   }
 279
 280   OwningPtr<MachOObject> MachOObj(MachOObject::LoadFromBuffer(Buff.take()));
 281
 282   const Target *TheTarget = GetTarget(MachOObj.get());
 283   if (!TheTarget) {
 284     // GetTarget prints out stuff.
 285     return;
 286   }
 287   const MCInstrInfo *InstrInfo = TheTarget->createMCInstrInfo();
 288   OwningPtr<MCInstrAnalysis>
 289     InstrAnalysis(TheTarget->createMCInstrAnalysis(InstrInfo));
 290
 291   // Set up disassembler.
 292   OwningPtr<const MCAsmInfo> AsmInfo(TheTarget->createMCAsmInfo(TripleName));
 293   OwningPtr<const MCSubtargetInfo>
 294     STI(TheTarget->createMCSubtargetInfo(TripleName, "", ""));
 295   OwningPtr<const MCDisassembler> DisAsm(TheTarget->createMCDisassembler(*STI));
 296   int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
 297   OwningPtr<MCInstPrinter> IP(TheTarget->createMCInstPrinter(
 298                               AsmPrinterVariant, *AsmInfo, *STI));
 299
 300   if (!InstrAnalysis || !AsmInfo || !STI || !DisAsm || !IP) {
 301     errs() << "error: couldn't initialize disassembler for target "
 302            << TripleName << '\n';
 303     return;
 304   }
 305
 306   outs() << '\n' << Filename << ":\n\n";
 307
 308   const macho::Header &Header = MachOObj->getHeader();
 309
 310   const MachOObject::LoadCommandInfo *SymtabLCI = 0;
 311   // First, find the symbol table segment.
 312   for (unsigned i = 0; i != Header.NumLoadCommands; ++i) {
 313     const MachOObject::LoadCommandInfo &LCI = MachOObj->getLoadCommandInfo(i);
 314     if (LCI.Command.Type == macho::LCT_Symtab) {
 315       SymtabLCI = &LCI;
 316       break;
 317     }
 318   }
 319
 320   // Read and register the symbol table data.
 321   InMemoryStruct<macho::SymtabLoadCommand> SymtabLC;
 322   MachOObj->ReadSymtabLoadCommand(*SymtabLCI, SymtabLC);
 323   MachOObj->RegisterStringTable(*SymtabLC);
 324
 325   std::vector<Section> Sections;
 326   std::vector<Symbol> Symbols;
 327   SmallVector<uint64_t, 8> FoundFns;
 328
 329   getSectionsAndSymbols(Header, MachOObj.get(), &SymtabLC, Sections, Symbols,
 330                         FoundFns);
 331
 332   // Make a copy of the unsorted symbol list. FIXME: duplication
 333   std::vector<Symbol> UnsortedSymbols(Symbols);
 334   // Sort the symbols by address, just in case they didn't come in that way.
 335   array_pod_sort(Symbols.begin(), Symbols.end());
 336
 337 #ifndef NDEBUG
 338   raw_ostream &DebugOut = DebugFlag ? dbgs() : nulls();
 339 #else
 340   raw_ostream &DebugOut = nulls();
 341 #endif
 342
 343   StringRef DebugAbbrevSection, DebugInfoSection, DebugArangesSection,
 344             DebugLineSection, DebugStrSection;
 345   OwningPtr<DIContext> diContext;
 346   OwningPtr<MachOObject> DSYMObj;
 347   MachOObject *DbgInfoObj = MachOObj.get();
 348   // Try to find debug info and set up the DIContext for it.
 349   if (UseDbg) {
 350     ArrayRef<Section> DebugSections = Sections;
 351     std::vector<Section> DSYMSections;
 352
 353     // A separate DSym file path was specified, parse it as a macho file,
 354     // get the sections and supply it to the section name parsing machinery.
 355     if (!DSYMFile.empty()) {
 356       OwningPtr<MemoryBuffer> Buf;
 357       if (error_code ec = MemoryBuffer::getFileOrSTDIN(DSYMFile.c_str(), Buf)) {
 358         errs() << "llvm-objdump: " << Filename << ": " << ec.message() << '\n';
 359         return;
 360       }
 361       DSYMObj.reset(MachOObject::LoadFromBuffer(Buf.take()));
 362       const macho::Header &Header = DSYMObj->getHeader();
 363
 364       std::vector<Symbol> Symbols;
 365       SmallVector<uint64_t, 8> FoundFns;
 366       getSectionsAndSymbols(Header, DSYMObj.get(), 0, DSYMSections, Symbols,
 367                             FoundFns);
 368       DebugSections = DSYMSections;
 369       DbgInfoObj = DSYMObj.get();
 370     }
 371
 372     // Find the named debug info sections.
 373     for (unsigned SectIdx = 0; SectIdx != DebugSections.size(); SectIdx++) {
 374       if (!strcmp(DebugSections[SectIdx].Name, "__debug_abbrev"))
 375         DebugAbbrevSection = DbgInfoObj->getData(DebugSections[SectIdx].Offset,
 376                                                  DebugSections[SectIdx].Size);
 377       else if (!strcmp(DebugSections[SectIdx].Name, "__debug_info"))
 378         DebugInfoSection = DbgInfoObj->getData(DebugSections[SectIdx].Offset,
 379                                                DebugSections[SectIdx].Size);
 380       else if (!strcmp(DebugSections[SectIdx].Name, "__debug_aranges"))
 381         DebugArangesSection = DbgInfoObj->getData(DebugSections[SectIdx].Offset,
 382                                                   DebugSections[SectIdx].Size);
 383       else if (!strcmp(DebugSections[SectIdx].Name, "__debug_line"))
 384         DebugLineSection = DbgInfoObj->getData(DebugSections[SectIdx].Offset,
 385                                                DebugSections[SectIdx].Size);
 386       else if (!strcmp(DebugSections[SectIdx].Name, "__debug_str"))
 387         DebugStrSection = DbgInfoObj->getData(DebugSections[SectIdx].Offset,
 388                                               DebugSections[SectIdx].Size);
 389     }
 390
 391     // Setup the DIContext.
 392     diContext.reset(DIContext::getDWARFContext(DbgInfoObj->isLittleEndian(),
 393                                                DebugInfoSection,
 394                                                DebugAbbrevSection,
 395                                                DebugArangesSection,
 396                                                DebugLineSection,
 397                                                DebugStrSection));
 398   }
 399
 400   FunctionMapTy FunctionMap;
 401   FunctionListTy Functions;
 402
 403   for (unsigned SectIdx = 0; SectIdx != Sections.size(); SectIdx++) {
 404     if (strcmp(Sections[SectIdx].Name, "__text"))
 405       continue; // Skip non-text sections
 406
 407     // Insert the functions from the function starts segment into our map.
 408     uint64_t VMAddr = Sections[SectIdx].Address - Sections[SectIdx].Offset;
 409     for (unsigned i = 0, e = FoundFns.size(); i != e; ++i)
 410       FunctionMap.insert(std::make_pair(FoundFns[i]+VMAddr, (MCFunction*)0));
 411
 412     StringRef Bytes = MachOObj->getData(Sections[SectIdx].Offset,
 413                                         Sections[SectIdx].Size);
 414     StringRefMemoryObject memoryObject(Bytes);
 415     bool symbolTableWorked = false;
 416
 417     // Parse relocations.
 418     std::vector<std::pair<uint64_t, uint32_t> > Relocs;
 419     for (unsigned j = 0; j != Sections[SectIdx].NumRelocs; ++j) {
 420       InMemoryStruct<macho::RelocationEntry> RE;
 421       MachOObj->ReadRelocationEntry(Sections[SectIdx].RelocTableOffset, j, RE);
 422       Relocs.push_back(std::make_pair(RE->Word0, RE->Word1 & 0xffffff));
 423     }
 424     array_pod_sort(Relocs.begin(), Relocs.end());
 425
 426     // Disassemble symbol by symbol.
 427     for (unsigned SymIdx = 0; SymIdx != Symbols.size(); SymIdx++) {
 428       // Make sure the symbol is defined in this section.
 429       if ((unsigned)Symbols[SymIdx].SectionIndex - 1 != SectIdx)
 430         continue;
 431
 432       // Start at the address of the symbol relative to the section's address.
 433       uint64_t Start = Symbols[SymIdx].Value - Sections[SectIdx].Address;
 434       // Stop disassembling either at the beginning of the next symbol or at
 435       // the end of the section.
 436       uint64_t End = (SymIdx+1 == Symbols.size() ||
 437           Symbols[SymIdx].SectionIndex != Symbols[SymIdx+1].SectionIndex) ?
 438           Sections[SectIdx].Size :
 439           Symbols[SymIdx+1].Value - Sections[SectIdx].Address;
 440       uint64_t Size;
 441
 442       if (Start >= End)
 443         continue;
 444
 445       symbolTableWorked = true;
 446
 447       if (!CFG) {
 448         // Normal disassembly, print addresses, bytes and mnemonic form.
 449         outs() << MachOObj->getStringAtIndex(Symbols[SymIdx].StringIndex)
 450           << ":\n";
 451         DILineInfo lastLine;
 452         for (uint64_t Index = Start; Index < End; Index += Size) {
 453           MCInst Inst;
 454
 455           if (DisAsm->getInstruction(Inst, Size, memoryObject, Index,
 456                                      DebugOut, nulls())) {
 457             outs() << format("%8llx:\t", Sections[SectIdx].Address + Index);
 458             DumpBytes(StringRef(Bytes.data() + Index, Size));
 459             IP->printInst(&Inst, outs(), "");
 460
 461             // Print debug info.
 462             if (diContext) {
 463               DILineInfo dli =
 464                 diContext->getLineInfoForAddress(Sections[SectIdx].Address +
 465                                                  Index);
 466               // Print valid line info if it changed.
 467               if (dli != lastLine && dli.getLine() != 0)
 468                 outs() << "\t## " << dli.getFileName() << ':'
 469                        << dli.getLine() << ':' << dli.getColumn();
 470               lastLine = dli;
 471             }
 472             outs() << "\n";
 473           } else {
 474             errs() << "llvm-objdump: warning: invalid instruction encoding\n";
 475             if (Size == 0)
 476               Size = 1; // skip illegible bytes
 477           }
 478         }
 479       } else {
 480         // Create CFG and use it for disassembly.
 481         createMCFunctionAndSaveCalls(
 482             MachOObj->getStringAtIndex(Symbols[SymIdx].StringIndex),
 483             DisAsm.get(), memoryObject, Start, End, InstrAnalysis.get(),
 484             Start, DebugOut, FunctionMap, Functions);
 485       }
 486     }
 487
 488     if (CFG) {
 489       if (!symbolTableWorked) {
 490         // Reading the symbol table didn't work, create a big __TEXT symbol.
 491         createMCFunctionAndSaveCalls("__TEXT", DisAsm.get(), memoryObject,
 492                                      0, Sections[SectIdx].Size,
 493                                      InstrAnalysis.get(),
 494                                      Sections[SectIdx].Offset, DebugOut,
 495                                      FunctionMap, Functions);
 496       }
 497       for (std::map<uint64_t, MCFunction*>::iterator mi = FunctionMap.begin(),
 498            me = FunctionMap.end(); mi != me; ++mi)
 499         if (mi->second == 0) {
 500           // Create functions for the remaining callees we have gathered,
 501           // but we didn't find a name for them.
 502           SmallVector<uint64_t, 16> Calls;
 503           MCFunction f =
 504             MCFunction::createFunctionFromMC("unknown", DisAsm.get(),
 505                                              memoryObject, mi->first,
 506                                              Sections[SectIdx].Size,
 507                                              InstrAnalysis.get(), DebugOut,
 508                                              Calls);
 509           Functions.push_back(f);
 510           mi->second = &Functions.back();
 511           for (unsigned i = 0, e = Calls.size(); i != e; ++i) {
 512             std::pair<uint64_t, MCFunction*> p(Calls[i], (MCFunction*)0);
 513             if (FunctionMap.insert(p).second)
 514               mi = FunctionMap.begin();
 515           }
 516         }
 517
 518       DenseSet<uint64_t> PrintedBlocks;
 519       for (unsigned ffi = 0, ffe = Functions.size(); ffi != ffe; ++ffi) {
 520         MCFunction &f = Functions[ffi];
 521         for (MCFunction::iterator fi = f.begin(), fe = f.end(); fi != fe; ++fi){
 522           if (!PrintedBlocks.insert(fi->first).second)
 523             continue; // We already printed this block.
 524
 525           // We assume a block has predecessors when it's the first block after
 526           // a symbol.
 527           bool hasPreds = FunctionMap.find(fi->first) != FunctionMap.end();
 528
 529           // See if this block has predecessors.
 530           // FIXME: Slow.
 531           for (MCFunction::iterator pi = f.begin(), pe = f.end(); pi != pe;
 532               ++pi)
 533             if (pi->second.contains(fi->first)) {
 534               hasPreds = true;
 535               break;
 536             }
 537
 538           // No predecessors, this is a data block. Print as .byte directives.
 539           if (!hasPreds) {
 540             uint64_t End = llvm::next(fi) == fe ? Sections[SectIdx].Size :
 541                                                   llvm::next(fi)->first;
 542             outs() << "# " << End-fi->first << " bytes of data:\n";
 543             for (unsigned pos = fi->first; pos != End; ++pos) {
 544               outs() << format("%8x:\t", Sections[SectIdx].Address + pos);
 545               DumpBytes(StringRef(Bytes.data() + pos, 1));
 546               outs() << format("\t.byte 0x%02x\n", (uint8_t)Bytes[pos]);
 547             }
 548             continue;
 549           }
 550
 551           if (fi->second.contains(fi->first)) // Print a header for simple loops
 552             outs() << "# Loop begin:\n";
 553
 554           DILineInfo lastLine;
 555           // Walk over the instructions and print them.
 556           for (unsigned ii = 0, ie = fi->second.getInsts().size(); ii != ie;
 557                ++ii) {
 558             const MCDecodedInst &Inst = fi->second.getInsts()[ii];
 559
 560             // If there's a symbol at this address, print its name.
 561             if (FunctionMap.find(Sections[SectIdx].Address + Inst.Address) !=
 562                 FunctionMap.end())
 563               outs() << FunctionMap[Sections[SectIdx].Address + Inst.Address]->
 564                                                              getName() << ":\n";
 565
 566             outs() << format("%8llx:\t", Sections[SectIdx].Address +
 567                                          Inst.Address);
 568             DumpBytes(StringRef(Bytes.data() + Inst.Address, Inst.Size));
 569
 570             if (fi->second.contains(fi->first)) // Indent simple loops.
 571               outs() << '\t';
 572
 573             IP->printInst(&Inst.Inst, outs(), "");
 574
 575             // Look for relocations inside this instructions, if there is one
 576             // print its target and additional information if available.
 577             for (unsigned j = 0; j != Relocs.size(); ++j)
 578               if (Relocs[j].first >= Sections[SectIdx].Address + Inst.Address &&
 579                   Relocs[j].first < Sections[SectIdx].Address + Inst.Address +
 580                                     Inst.Size) {
 581                 outs() << "\t# "
 582                    << MachOObj->getStringAtIndex(
 583                                   UnsortedSymbols[Relocs[j].second].StringIndex)
 584                    << ' ';
 585                 DumpAddress(UnsortedSymbols[Relocs[j].second].Value, Sections,
 586                             MachOObj.get(), outs());
 587               }
 588
 589             // If this instructions contains an address, see if we can evaluate
 590             // it and print additional information.
 591             uint64_t targ = InstrAnalysis->evaluateBranch(Inst.Inst,
 592                                                           Inst.Address,
 593                                                           Inst.Size);
 594             if (targ != -1ULL)
 595               DumpAddress(targ, Sections, MachOObj.get(), outs());
 596
 597             // Print debug info.
 598             if (diContext) {
 599               DILineInfo dli =
 600                 diContext->getLineInfoForAddress(Sections[SectIdx].Address +
 601                                                  Inst.Address);
 602               // Print valid line info if it changed.
 603               if (dli != lastLine && dli.getLine() != 0)
 604                 outs() << "\t## " << dli.getFileName() << ':'
 605                        << dli.getLine() << ':' << dli.getColumn();
 606               lastLine = dli;
 607             }
 608
 609             outs() << '\n';
 610           }
 611         }
 612
 613         emitDOTFile((f.getName().str() + ".dot").c_str(), f, IP.get());
 614       }
 615     }
 616   }
 617 }