lib/Object/MachOObjectFile.cpp

   1 //===- MachOObjectFile.cpp - Mach-O object file binding ---------*- C++ -*-===//
   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 defines the MachOObjectFile class, which binds the MachOObject
  11 // class to the generic ObjectFile wrapper.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "llvm/ADT/Triple.h"
  16 #include "llvm/Object/MachO.h"
  17 #include "llvm/Object/MachOFormat.h"
  18 #include "llvm/Support/Format.h"
  19 #include "llvm/Support/MemoryBuffer.h"
  20
  21 #include <cctype>
  22 #include <cstring>
  23 #include <limits>
  24
  25 using namespace llvm;
  26 using namespace object;
  27
  28 namespace llvm {
  29 namespace object {
  30
  31 MachOObjectFile::MachOObjectFile(MemoryBuffer *Object, MachOObject *MOO,
  32                                  error_code &ec)
  33     : ObjectFile(Binary::ID_MachO, Object, ec),
  34       MachOObj(MOO),
  35       RegisteredStringTable(std::numeric_limits<uint32_t>::max()) {
  36   DataRefImpl DRI;
  37   moveToNextSection(DRI);
  38   uint32_t LoadCommandCount = MachOObj->getHeader().NumLoadCommands;
  39   while (DRI.d.a < LoadCommandCount) {
  40     Sections.push_back(DRI);
  41     DRI.d.b++;
  42     moveToNextSection(DRI);
  43   }
  44 }
  45
  46
  47 ObjectFile *ObjectFile::createMachOObjectFile(MemoryBuffer *Buffer) {
  48   error_code ec;
  49   std::string Err;
  50   MachOObject *MachOObj = MachOObject::LoadFromBuffer(Buffer, &Err);
  51   if (!MachOObj)
  52     return NULL;
  53   return new MachOObjectFile(Buffer, MachOObj, ec);
  54 }
  55
  56 /*===-- Symbols -----------------------------------------------------------===*/
  57
  58 void MachOObjectFile::moveToNextSymbol(DataRefImpl &DRI) const {
  59   uint32_t LoadCommandCount = MachOObj->getHeader().NumLoadCommands;
  60   while (DRI.d.a < LoadCommandCount) {
  61     LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
  62     if (LCI.Command.Type == macho::LCT_Symtab) {
  63       InMemoryStruct<macho::SymtabLoadCommand> SymtabLoadCmd;
  64       MachOObj->ReadSymtabLoadCommand(LCI, SymtabLoadCmd);
  65       if (DRI.d.b < SymtabLoadCmd->NumSymbolTableEntries)
  66         return;
  67     }
  68
  69     DRI.d.a++;
  70     DRI.d.b = 0;
  71   }
  72 }
  73
  74 void MachOObjectFile::getSymbolTableEntry(DataRefImpl DRI,
  75     InMemoryStruct<macho::SymbolTableEntry> &Res) const {
  76   InMemoryStruct<macho::SymtabLoadCommand> SymtabLoadCmd;
  77   LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
  78   MachOObj->ReadSymtabLoadCommand(LCI, SymtabLoadCmd);
  79
  80   if (RegisteredStringTable != DRI.d.a) {
  81     MachOObj->RegisterStringTable(*SymtabLoadCmd);
  82     RegisteredStringTable = DRI.d.a;
  83   }
  84
  85   MachOObj->ReadSymbolTableEntry(SymtabLoadCmd->SymbolTableOffset, DRI.d.b,
  86                                  Res);
  87 }
  88
  89 void MachOObjectFile::getSymbol64TableEntry(DataRefImpl DRI,
  90     InMemoryStruct<macho::Symbol64TableEntry> &Res) const {
  91   InMemoryStruct<macho::SymtabLoadCommand> SymtabLoadCmd;
  92   LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
  93   MachOObj->ReadSymtabLoadCommand(LCI, SymtabLoadCmd);
  94
  95   if (RegisteredStringTable != DRI.d.a) {
  96     MachOObj->RegisterStringTable(*SymtabLoadCmd);
  97     RegisteredStringTable = DRI.d.a;
  98   }
  99
 100   MachOObj->ReadSymbol64TableEntry(SymtabLoadCmd->SymbolTableOffset, DRI.d.b,
 101                                    Res);
 102 }
 103
 104
 105 error_code MachOObjectFile::getSymbolNext(DataRefImpl DRI,
 106                                           SymbolRef &Result) const {
 107   DRI.d.b++;
 108   moveToNextSymbol(DRI);
 109   Result = SymbolRef(DRI, this);
 110   return object_error::success;
 111 }
 112
 113 error_code MachOObjectFile::getSymbolName(DataRefImpl DRI,
 114                                           StringRef &Result) const {
 115   if (MachOObj->is64Bit()) {
 116     InMemoryStruct<macho::Symbol64TableEntry> Entry;
 117     getSymbol64TableEntry(DRI, Entry);
 118     Result = MachOObj->getStringAtIndex(Entry->StringIndex);
 119   } else {
 120     InMemoryStruct<macho::SymbolTableEntry> Entry;
 121     getSymbolTableEntry(DRI, Entry);
 122     Result = MachOObj->getStringAtIndex(Entry->StringIndex);
 123   }
 124   return object_error::success;
 125 }
 126
 127 error_code MachOObjectFile::getSymbolFileOffset(DataRefImpl DRI,
 128                                                 uint64_t &Result) const {
 129   if (MachOObj->is64Bit()) {
 130     InMemoryStruct<macho::Symbol64TableEntry> Entry;
 131     getSymbol64TableEntry(DRI, Entry);
 132     Result = Entry->Value;
 133     if (Entry->SectionIndex) {
 134       InMemoryStruct<macho::Section64> Section;
 135       getSection64(Sections[Entry->SectionIndex-1], Section);
 136       Result += Section->Offset - Section->Address;
 137     }
 138   } else {
 139     InMemoryStruct<macho::SymbolTableEntry> Entry;
 140     getSymbolTableEntry(DRI, Entry);
 141     Result = Entry->Value;
 142     if (Entry->SectionIndex) {
 143       InMemoryStruct<macho::Section> Section;
 144       getSection(Sections[Entry->SectionIndex-1], Section);
 145       Result += Section->Offset - Section->Address;
 146     }
 147   }
 148
 149   return object_error::success;
 150 }
 151
 152 error_code MachOObjectFile::getSymbolAddress(DataRefImpl DRI,
 153                                              uint64_t &Result) const {
 154   if (MachOObj->is64Bit()) {
 155     InMemoryStruct<macho::Symbol64TableEntry> Entry;
 156     getSymbol64TableEntry(DRI, Entry);
 157     Result = Entry->Value;
 158   } else {
 159     InMemoryStruct<macho::SymbolTableEntry> Entry;
 160     getSymbolTableEntry(DRI, Entry);
 161     Result = Entry->Value;
 162   }
 163   return object_error::success;
 164 }
 165
 166 error_code MachOObjectFile::getSymbolSize(DataRefImpl DRI,
 167                                           uint64_t &Result) const {
 168   uint32_t LoadCommandCount = MachOObj->getHeader().NumLoadCommands;
 169   uint64_t BeginOffset;
 170   uint64_t EndOffset = 0;
 171   uint8_t SectionIndex;
 172   if (MachOObj->is64Bit()) {
 173     InMemoryStruct<macho::Symbol64TableEntry> Entry;
 174     getSymbol64TableEntry(DRI, Entry);
 175     BeginOffset = Entry->Value;
 176     SectionIndex = Entry->SectionIndex;
 177     if (!SectionIndex) {
 178       uint32_t flags = SymbolRef::SF_None;
 179       getSymbolFlags(DRI, flags);
 180       if (flags & SymbolRef::SF_Common)
 181         Result = Entry->Value;
 182       else
 183         Result = UnknownAddressOrSize;
 184       return object_error::success;
 185     }
 186     // Unfortunately symbols are unsorted so we need to touch all
 187     // symbols from load command
 188     DRI.d.b = 0;
 189     uint32_t Command = DRI.d.a;
 190     while (Command == DRI.d.a) {
 191       moveToNextSymbol(DRI);
 192       if (DRI.d.a < LoadCommandCount) {
 193         getSymbol64TableEntry(DRI, Entry);
 194         if (Entry->SectionIndex == SectionIndex && Entry->Value > BeginOffset)
 195           if (!EndOffset || Entry->Value < EndOffset)
 196             EndOffset = Entry->Value;
 197       }
 198       DRI.d.b++;
 199     }
 200   } else {
 201     InMemoryStruct<macho::SymbolTableEntry> Entry;
 202     getSymbolTableEntry(DRI, Entry);
 203     BeginOffset = Entry->Value;
 204     SectionIndex = Entry->SectionIndex;
 205     if (!SectionIndex) {
 206       uint32_t flags = SymbolRef::SF_None;
 207       getSymbolFlags(DRI, flags);
 208       if (flags & SymbolRef::SF_Common)
 209         Result = Entry->Value;
 210       else
 211         Result = UnknownAddressOrSize;
 212       return object_error::success;
 213     }
 214     // Unfortunately symbols are unsorted so we need to touch all
 215     // symbols from load command
 216     DRI.d.b = 0;
 217     uint32_t Command = DRI.d.a;
 218     while (Command == DRI.d.a) {
 219       moveToNextSymbol(DRI);
 220       if (DRI.d.a < LoadCommandCount) {
 221         getSymbolTableEntry(DRI, Entry);
 222         if (Entry->SectionIndex == SectionIndex && Entry->Value > BeginOffset)
 223           if (!EndOffset || Entry->Value < EndOffset)
 224             EndOffset = Entry->Value;
 225       }
 226       DRI.d.b++;
 227     }
 228   }
 229   if (!EndOffset) {
 230     uint64_t Size;
 231     getSectionSize(Sections[SectionIndex-1], Size);
 232     getSectionAddress(Sections[SectionIndex-1], EndOffset);
 233     EndOffset += Size;
 234   }
 235   Result = EndOffset - BeginOffset;
 236   return object_error::success;
 237 }
 238
 239 error_code MachOObjectFile::getSymbolNMTypeChar(DataRefImpl DRI,
 240                                                 char &Result) const {
 241   uint8_t Type, Flags;
 242   if (MachOObj->is64Bit()) {
 243     InMemoryStruct<macho::Symbol64TableEntry> Entry;
 244     getSymbol64TableEntry(DRI, Entry);
 245     Type = Entry->Type;
 246     Flags = Entry->Flags;
 247   } else {
 248     InMemoryStruct<macho::SymbolTableEntry> Entry;
 249     getSymbolTableEntry(DRI, Entry);
 250     Type = Entry->Type;
 251     Flags = Entry->Flags;
 252   }
 253
 254   char Char;
 255   switch (Type & macho::STF_TypeMask) {
 256     case macho::STT_Undefined:
 257       Char = 'u';
 258       break;
 259     case macho::STT_Absolute:
 260     case macho::STT_Section:
 261       Char = 's';
 262       break;
 263     default:
 264       Char = '?';
 265       break;
 266   }
 267
 268   if (Flags & (macho::STF_External | macho::STF_PrivateExtern))
 269     Char = toupper(Char);
 270   Result = Char;
 271   return object_error::success;
 272 }
 273
 274 error_code MachOObjectFile::getSymbolFlags(DataRefImpl DRI,
 275                                            uint32_t &Result) const {
 276   uint16_t MachOFlags;
 277   uint8_t MachOType;
 278   if (MachOObj->is64Bit()) {
 279     InMemoryStruct<macho::Symbol64TableEntry> Entry;
 280     getSymbol64TableEntry(DRI, Entry);
 281     MachOFlags = Entry->Flags;
 282     MachOType = Entry->Type;
 283   } else {
 284     InMemoryStruct<macho::SymbolTableEntry> Entry;
 285     getSymbolTableEntry(DRI, Entry);
 286     MachOFlags = Entry->Flags;
 287     MachOType = Entry->Type;
 288   }
 289
 290   // TODO: Correctly set SF_ThreadLocal
 291   Result = SymbolRef::SF_None;
 292
 293   if ((MachOType & MachO::NlistMaskType) == MachO::NListTypeUndefined)
 294     Result |= SymbolRef::SF_Undefined;
 295
 296   if (MachOFlags & macho::STF_StabsEntryMask)
 297     Result |= SymbolRef::SF_FormatSpecific;
 298
 299   if (MachOType & MachO::NlistMaskExternal) {
 300     Result |= SymbolRef::SF_Global;
 301     if ((MachOType & MachO::NlistMaskType) == MachO::NListTypeUndefined)
 302       Result |= SymbolRef::SF_Common;
 303   }
 304
 305   if (MachOFlags & (MachO::NListDescWeakRef | MachO::NListDescWeakDef))
 306     Result |= SymbolRef::SF_Weak;
 307
 308   if ((MachOType & MachO::NlistMaskType) == MachO::NListTypeAbsolute)
 309     Result |= SymbolRef::SF_Absolute;
 310
 311   return object_error::success;
 312 }
 313
 314 error_code MachOObjectFile::getSymbolSection(DataRefImpl Symb,
 315                                              section_iterator &Res) const {
 316   uint8_t index;
 317   if (MachOObj->is64Bit()) {
 318     InMemoryStruct<macho::Symbol64TableEntry> Entry;
 319     getSymbol64TableEntry(Symb, Entry);
 320     index = Entry->SectionIndex;
 321   } else {
 322     InMemoryStruct<macho::SymbolTableEntry> Entry;
 323     getSymbolTableEntry(Symb, Entry);
 324     index = Entry->SectionIndex;
 325   }
 326
 327   if (index == 0)
 328     Res = end_sections();
 329   else
 330     Res = section_iterator(SectionRef(Sections[index-1], this));
 331
 332   return object_error::success;
 333 }
 334
 335 error_code MachOObjectFile::getSymbolType(DataRefImpl Symb,
 336                                           SymbolRef::Type &Res) const {
 337   uint8_t n_type;
 338   if (MachOObj->is64Bit()) {
 339     InMemoryStruct<macho::Symbol64TableEntry> Entry;
 340     getSymbol64TableEntry(Symb, Entry);
 341     n_type = Entry->Type;
 342   } else {
 343     InMemoryStruct<macho::SymbolTableEntry> Entry;
 344     getSymbolTableEntry(Symb, Entry);
 345     n_type = Entry->Type;
 346   }
 347   Res = SymbolRef::ST_Other;
 348
 349   // If this is a STAB debugging symbol, we can do nothing more.
 350   if (n_type & MachO::NlistMaskStab) {
 351     Res = SymbolRef::ST_Debug;
 352     return object_error::success;
 353   }
 354
 355   switch (n_type & MachO::NlistMaskType) {
 356     case MachO::NListTypeUndefined :
 357       Res = SymbolRef::ST_Unknown;
 358       break;
 359     case MachO::NListTypeSection :
 360       Res = SymbolRef::ST_Function;
 361       break;
 362   }
 363   return object_error::success;
 364 }
 365
 366
 367 symbol_iterator MachOObjectFile::begin_symbols() const {
 368   // DRI.d.a = segment number; DRI.d.b = symbol index.
 369   DataRefImpl DRI;
 370   moveToNextSymbol(DRI);
 371   return symbol_iterator(SymbolRef(DRI, this));
 372 }
 373
 374 symbol_iterator MachOObjectFile::end_symbols() const {
 375   DataRefImpl DRI;
 376   DRI.d.a = MachOObj->getHeader().NumLoadCommands;
 377   return symbol_iterator(SymbolRef(DRI, this));
 378 }
 379
 380 symbol_iterator MachOObjectFile::begin_dynamic_symbols() const {
 381   // TODO: implement
 382   report_fatal_error("Dynamic symbols unimplemented in MachOObjectFile");
 383 }
 384
 385 symbol_iterator MachOObjectFile::end_dynamic_symbols() const {
 386   // TODO: implement
 387   report_fatal_error("Dynamic symbols unimplemented in MachOObjectFile");
 388 }
 389
 390 library_iterator MachOObjectFile::begin_libraries_needed() const {
 391   // TODO: implement
 392   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
 393 }
 394
 395 library_iterator MachOObjectFile::end_libraries_needed() const {
 396   // TODO: implement
 397   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
 398 }
 399
 400 StringRef MachOObjectFile::getLoadName() const {
 401   // TODO: Implement
 402   report_fatal_error("get_load_name() unimplemented in MachOObjectFile");
 403 }
 404
 405 /*===-- Sections ----------------------------------------------------------===*/
 406
 407 void MachOObjectFile::moveToNextSection(DataRefImpl &DRI) const {
 408   uint32_t LoadCommandCount = MachOObj->getHeader().NumLoadCommands;
 409   while (DRI.d.a < LoadCommandCount) {
 410     LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
 411     if (LCI.Command.Type == macho::LCT_Segment) {
 412       InMemoryStruct<macho::SegmentLoadCommand> SegmentLoadCmd;
 413       MachOObj->ReadSegmentLoadCommand(LCI, SegmentLoadCmd);
 414       if (DRI.d.b < SegmentLoadCmd->NumSections)
 415         return;
 416     } else if (LCI.Command.Type == macho::LCT_Segment64) {
 417       InMemoryStruct<macho::Segment64LoadCommand> Segment64LoadCmd;
 418       MachOObj->ReadSegment64LoadCommand(LCI, Segment64LoadCmd);
 419       if (DRI.d.b < Segment64LoadCmd->NumSections)
 420         return;
 421     }
 422
 423     DRI.d.a++;
 424     DRI.d.b = 0;
 425   }
 426 }
 427
 428 error_code MachOObjectFile::getSectionNext(DataRefImpl DRI,
 429                                            SectionRef &Result) const {
 430   DRI.d.b++;
 431   moveToNextSection(DRI);
 432   Result = SectionRef(DRI, this);
 433   return object_error::success;
 434 }
 435
 436 void
 437 MachOObjectFile::getSection(DataRefImpl DRI,
 438                             InMemoryStruct<macho::Section> &Res) const {
 439   InMemoryStruct<macho::SegmentLoadCommand> SLC;
 440   LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
 441   MachOObj->ReadSegmentLoadCommand(LCI, SLC);
 442   MachOObj->ReadSection(LCI, DRI.d.b, Res);
 443 }
 444
 445 std::size_t MachOObjectFile::getSectionIndex(DataRefImpl Sec) const {
 446   SectionList::const_iterator loc =
 447     std::find(Sections.begin(), Sections.end(), Sec);
 448   assert(loc != Sections.end() && "Sec is not a valid section!");
 449   return std::distance(Sections.begin(), loc);
 450 }
 451
 452 void
 453 MachOObjectFile::getSection64(DataRefImpl DRI,
 454                             InMemoryStruct<macho::Section64> &Res) const {
 455   InMemoryStruct<macho::Segment64LoadCommand> SLC;
 456   LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
 457   MachOObj->ReadSegment64LoadCommand(LCI, SLC);
 458   MachOObj->ReadSection64(LCI, DRI.d.b, Res);
 459 }
 460
 461 static bool is64BitLoadCommand(const MachOObject *MachOObj, DataRefImpl DRI) {
 462   LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
 463   if (LCI.Command.Type == macho::LCT_Segment64)
 464     return true;
 465   assert(LCI.Command.Type == macho::LCT_Segment && "Unexpected Type.");
 466   return false;
 467 }
 468
 469 error_code MachOObjectFile::getSectionName(DataRefImpl DRI,
 470                                            StringRef &Result) const {
 471   // FIXME: thread safety.
 472   static char result[34];
 473   if (is64BitLoadCommand(MachOObj, DRI)) {
 474     InMemoryStruct<macho::Segment64LoadCommand> SLC;
 475     LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
 476     MachOObj->ReadSegment64LoadCommand(LCI, SLC);
 477     InMemoryStruct<macho::Section64> Sect;
 478     MachOObj->ReadSection64(LCI, DRI.d.b, Sect);
 479
 480     strcpy(result, Sect->SegmentName);
 481     strcat(result, ",");
 482     strcat(result, Sect->Name);
 483   } else {
 484     InMemoryStruct<macho::SegmentLoadCommand> SLC;
 485     LoadCommandInfo LCI = MachOObj->getLoadCommandInfo(DRI.d.a);
 486     MachOObj->ReadSegmentLoadCommand(LCI, SLC);
 487     InMemoryStruct<macho::Section> Sect;
 488     MachOObj->ReadSection(LCI, DRI.d.b, Sect);
 489
 490     strcpy(result, Sect->SegmentName);
 491     strcat(result, ",");
 492     strcat(result, Sect->Name);
 493   }
 494   Result = StringRef(result);
 495   return object_error::success;
 496 }
 497
 498 error_code MachOObjectFile::getSectionAddress(DataRefImpl DRI,
 499                                               uint64_t &Result) const {
 500   if (is64BitLoadCommand(MachOObj, DRI)) {
 501     InMemoryStruct<macho::Section64> Sect;
 502     getSection64(DRI, Sect);
 503     Result = Sect->Address;
 504   } else {
 505     InMemoryStruct<macho::Section> Sect;
 506     getSection(DRI, Sect);
 507     Result = Sect->Address;
 508   }
 509   return object_error::success;
 510 }
 511
 512 error_code MachOObjectFile::getSectionSize(DataRefImpl DRI,
 513                                            uint64_t &Result) const {
 514   if (is64BitLoadCommand(MachOObj, DRI)) {
 515     InMemoryStruct<macho::Section64> Sect;
 516     getSection64(DRI, Sect);
 517     Result = Sect->Size;
 518   } else {
 519     InMemoryStruct<macho::Section> Sect;
 520     getSection(DRI, Sect);
 521     Result = Sect->Size;
 522   }
 523   return object_error::success;
 524 }
 525
 526 error_code MachOObjectFile::getSectionContents(DataRefImpl DRI,
 527                                                StringRef &Result) const {
 528   if (is64BitLoadCommand(MachOObj, DRI)) {
 529     InMemoryStruct<macho::Section64> Sect;
 530     getSection64(DRI, Sect);
 531     Result = MachOObj->getData(Sect->Offset, Sect->Size);
 532   } else {
 533     InMemoryStruct<macho::Section> Sect;
 534     getSection(DRI, Sect);
 535     Result = MachOObj->getData(Sect->Offset, Sect->Size);
 536   }
 537   return object_error::success;
 538 }
 539
 540 error_code MachOObjectFile::getSectionAlignment(DataRefImpl DRI,
 541                                                 uint64_t &Result) const {
 542   if (is64BitLoadCommand(MachOObj, DRI)) {
 543     InMemoryStruct<macho::Section64> Sect;
 544     getSection64(DRI, Sect);
 545     Result = uint64_t(1) << Sect->Align;
 546   } else {
 547     InMemoryStruct<macho::Section> Sect;
 548     getSection(DRI, Sect);
 549     Result = uint64_t(1) << Sect->Align;
 550   }
 551   return object_error::success;
 552 }
 553
 554 error_code MachOObjectFile::isSectionText(DataRefImpl DRI,
 555                                           bool &Result) const {
 556   if (is64BitLoadCommand(MachOObj, DRI)) {
 557     InMemoryStruct<macho::Section64> Sect;
 558     getSection64(DRI, Sect);
 559     Result = !strcmp(Sect->Name, "__text");
 560   } else {
 561     InMemoryStruct<macho::Section> Sect;
 562     getSection(DRI, Sect);
 563     Result = !strcmp(Sect->Name, "__text");
 564   }
 565   return object_error::success;
 566 }
 567
 568 error_code MachOObjectFile::isSectionData(DataRefImpl DRI,
 569                                           bool &Result) const {
 570   // FIXME: Unimplemented.
 571   Result = false;
 572   return object_error::success;
 573 }
 574
 575 error_code MachOObjectFile::isSectionBSS(DataRefImpl DRI,
 576                                          bool &Result) const {
 577   // FIXME: Unimplemented.
 578   Result = false;
 579   return object_error::success;
 580 }
 581
 582 error_code MachOObjectFile::isSectionRequiredForExecution(DataRefImpl Sec,
 583                                                           bool &Result) const {
 584   // FIXME: Unimplemented.
 585   Result = true;
 586   return object_error::success;
 587 }
 588
 589 error_code MachOObjectFile::isSectionVirtual(DataRefImpl Sec,
 590                                              bool &Result) const {
 591   // FIXME: Unimplemented.
 592   Result = false;
 593   return object_error::success;
 594 }
 595
 596 error_code MachOObjectFile::isSectionZeroInit(DataRefImpl DRI,
 597                                               bool &Result) const {
 598   if (MachOObj->is64Bit()) {
 599     InMemoryStruct<macho::Section64> Sect;
 600     getSection64(DRI, Sect);
 601     unsigned SectionType = Sect->Flags & MachO::SectionFlagMaskSectionType;
 602     Result = (SectionType == MachO::SectionTypeZeroFill ||
 603               SectionType == MachO::SectionTypeZeroFillLarge);
 604   } else {
 605     InMemoryStruct<macho::Section> Sect;
 606     getSection(DRI, Sect);
 607     unsigned SectionType = Sect->Flags & MachO::SectionFlagMaskSectionType;
 608     Result = (SectionType == MachO::SectionTypeZeroFill ||
 609               SectionType == MachO::SectionTypeZeroFillLarge);
 610   }
 611
 612   return object_error::success;
 613 }
 614
 615 error_code MachOObjectFile::isSectionReadOnlyData(DataRefImpl Sec,
 616                                                   bool &Result) const {
 617   // Consider using the code from isSectionText to look for __const sections.
 618   // Alternately, emit S_ATTR_PURE_INSTRUCTIONS and/or S_ATTR_SOME_INSTRUCTIONS
 619   // to use section attributes to distinguish code from data.
 620
 621   // FIXME: Unimplemented.
 622   Result = false;
 623   return object_error::success;
 624 }
 625
 626 error_code MachOObjectFile::sectionContainsSymbol(DataRefImpl Sec,
 627                                                   DataRefImpl Symb,
 628                                                   bool &Result) const {
 629   SymbolRef::Type ST;
 630   getSymbolType(Symb, ST);
 631   if (ST == SymbolRef::ST_Unknown) {
 632     Result = false;
 633     return object_error::success;
 634   }
 635
 636   uint64_t SectBegin, SectEnd;
 637   getSectionAddress(Sec, SectBegin);
 638   getSectionSize(Sec, SectEnd);
 639   SectEnd += SectBegin;
 640
 641   if (MachOObj->is64Bit()) {
 642     InMemoryStruct<macho::Symbol64TableEntry> Entry;
 643     getSymbol64TableEntry(Symb, Entry);
 644     uint64_t SymAddr= Entry->Value;
 645     Result = (SymAddr >= SectBegin) && (SymAddr < SectEnd);
 646   } else {
 647     InMemoryStruct<macho::SymbolTableEntry> Entry;
 648     getSymbolTableEntry(Symb, Entry);
 649     uint64_t SymAddr= Entry->Value;
 650     Result = (SymAddr >= SectBegin) && (SymAddr < SectEnd);
 651   }
 652
 653   return object_error::success;
 654 }
 655
 656 relocation_iterator MachOObjectFile::getSectionRelBegin(DataRefImpl Sec) const {
 657   DataRefImpl ret;
 658   ret.d.b = getSectionIndex(Sec);
 659   return relocation_iterator(RelocationRef(ret, this));
 660 }
 661 relocation_iterator MachOObjectFile::getSectionRelEnd(DataRefImpl Sec) const {
 662   uint32_t last_reloc;
 663   if (is64BitLoadCommand(MachOObj, Sec)) {
 664     InMemoryStruct<macho::Section64> Sect;
 665     getSection64(Sec, Sect);
 666     last_reloc = Sect->NumRelocationTableEntries;
 667   } else {
 668     InMemoryStruct<macho::Section> Sect;
 669     getSection(Sec, Sect);
 670     last_reloc = Sect->NumRelocationTableEntries;
 671   }
 672   DataRefImpl ret;
 673   ret.d.a = last_reloc;
 674   ret.d.b = getSectionIndex(Sec);
 675   return relocation_iterator(RelocationRef(ret, this));
 676 }
 677
 678 section_iterator MachOObjectFile::begin_sections() const {
 679   DataRefImpl DRI;
 680   moveToNextSection(DRI);
 681   return section_iterator(SectionRef(DRI, this));
 682 }
 683
 684 section_iterator MachOObjectFile::end_sections() const {
 685   DataRefImpl DRI;
 686   DRI.d.a = MachOObj->getHeader().NumLoadCommands;
 687   return section_iterator(SectionRef(DRI, this));
 688 }
 689
 690 /*===-- Relocations -------------------------------------------------------===*/
 691
 692 void MachOObjectFile::
 693 getRelocation(DataRefImpl Rel,
 694               InMemoryStruct<macho::RelocationEntry> &Res) const {
 695   uint32_t relOffset;
 696   if (MachOObj->is64Bit()) {
 697     InMemoryStruct<macho::Section64> Sect;
 698     getSection64(Sections[Rel.d.b], Sect);
 699     relOffset = Sect->RelocationTableOffset;
 700   } else {
 701     InMemoryStruct<macho::Section> Sect;
 702     getSection(Sections[Rel.d.b], Sect);
 703     relOffset = Sect->RelocationTableOffset;
 704   }
 705   MachOObj->ReadRelocationEntry(relOffset, Rel.d.a, Res);
 706 }
 707 error_code MachOObjectFile::getRelocationNext(DataRefImpl Rel,
 708                                               RelocationRef &Res) const {
 709   ++Rel.d.a;
 710   Res = RelocationRef(Rel, this);
 711   return object_error::success;
 712 }
 713 error_code MachOObjectFile::getRelocationAddress(DataRefImpl Rel,
 714                                                  uint64_t &Res) const {
 715   const uint8_t* sectAddress = 0;
 716   if (MachOObj->is64Bit()) {
 717     InMemoryStruct<macho::Section64> Sect;
 718     getSection64(Sections[Rel.d.b], Sect);
 719     sectAddress += Sect->Address;
 720   } else {
 721     InMemoryStruct<macho::Section> Sect;
 722     getSection(Sections[Rel.d.b], Sect);
 723     sectAddress += Sect->Address;
 724   }
 725   InMemoryStruct<macho::RelocationEntry> RE;
 726   getRelocation(Rel, RE);
 727
 728   unsigned Arch = getArch();
 729   bool isScattered = (Arch != Triple::x86_64) &&
 730                      (RE->Word0 & macho::RF_Scattered);
 731   uint64_t RelAddr = 0;
 732   if (isScattered)
 733     RelAddr = RE->Word0 & 0xFFFFFF;
 734   else
 735     RelAddr = RE->Word0;
 736
 737   Res = reinterpret_cast<uintptr_t>(sectAddress + RelAddr);
 738   return object_error::success;
 739 }
 740 error_code MachOObjectFile::getRelocationOffset(DataRefImpl Rel,
 741                                                 uint64_t &Res) const {
 742   InMemoryStruct<macho::RelocationEntry> RE;
 743   getRelocation(Rel, RE);
 744
 745   unsigned Arch = getArch();
 746   bool isScattered = (Arch != Triple::x86_64) &&
 747                      (RE->Word0 & macho::RF_Scattered);
 748   if (isScattered)
 749     Res = RE->Word0 & 0xFFFFFF;
 750   else
 751     Res = RE->Word0;
 752   return object_error::success;
 753 }
 754 error_code MachOObjectFile::getRelocationSymbol(DataRefImpl Rel,
 755                                                 SymbolRef &Res) const {
 756   InMemoryStruct<macho::RelocationEntry> RE;
 757   getRelocation(Rel, RE);
 758   uint32_t SymbolIdx = RE->Word1 & 0xffffff;
 759   bool isExtern = (RE->Word1 >> 27) & 1;
 760
 761   DataRefImpl Sym;
 762   moveToNextSymbol(Sym);
 763   if (isExtern) {
 764     for (unsigned i = 0; i < SymbolIdx; i++) {
 765       Sym.d.b++;
 766       moveToNextSymbol(Sym);
 767       assert(Sym.d.a < MachOObj->getHeader().NumLoadCommands &&
 768              "Relocation symbol index out of range!");
 769     }
 770   }
 771   Res = SymbolRef(Sym, this);
 772   return object_error::success;
 773 }
 774 error_code MachOObjectFile::getRelocationType(DataRefImpl Rel,
 775                                               uint64_t &Res) const {
 776   InMemoryStruct<macho::RelocationEntry> RE;
 777   getRelocation(Rel, RE);
 778   Res = RE->Word0;
 779   Res <<= 32;
 780   Res |= RE->Word1;
 781   return object_error::success;
 782 }
 783 error_code MachOObjectFile::getRelocationTypeName(DataRefImpl Rel,
 784                                           SmallVectorImpl<char> &Result) const {
 785   // TODO: Support scattered relocations.
 786   StringRef res;
 787   InMemoryStruct<macho::RelocationEntry> RE;
 788   getRelocation(Rel, RE);
 789
 790   unsigned Arch = getArch();
 791   bool isScattered = (Arch != Triple::x86_64) &&
 792                      (RE->Word0 & macho::RF_Scattered);
 793
 794   unsigned r_type;
 795   if (isScattered)
 796     r_type = (RE->Word0 >> 24) & 0xF;
 797   else
 798     r_type = (RE->Word1 >> 28) & 0xF;
 799
 800   switch (Arch) {
 801     case Triple::x86: {
 802       static const char *const Table[] =  {
 803         "GENERIC_RELOC_VANILLA",
 804         "GENERIC_RELOC_PAIR",
 805         "GENERIC_RELOC_SECTDIFF",
 806         "GENERIC_RELOC_PB_LA_PTR",
 807         "GENERIC_RELOC_LOCAL_SECTDIFF",
 808         "GENERIC_RELOC_TLV" };
 809
 810       if (r_type > 6)
 811         res = "Unknown";
 812       else
 813         res = Table[r_type];
 814       break;
 815     }
 816     case Triple::x86_64: {
 817       static const char *const Table[] =  {
 818         "X86_64_RELOC_UNSIGNED",
 819         "X86_64_RELOC_SIGNED",
 820         "X86_64_RELOC_BRANCH",
 821         "X86_64_RELOC_GOT_LOAD",
 822         "X86_64_RELOC_GOT",
 823         "X86_64_RELOC_SUBTRACTOR",
 824         "X86_64_RELOC_SIGNED_1",
 825         "X86_64_RELOC_SIGNED_2",
 826         "X86_64_RELOC_SIGNED_4",
 827         "X86_64_RELOC_TLV" };
 828
 829       if (r_type > 9)
 830         res = "Unknown";
 831       else
 832         res = Table[r_type];
 833       break;
 834     }
 835     case Triple::arm: {
 836       static const char *const Table[] =  {
 837         "ARM_RELOC_VANILLA",
 838         "ARM_RELOC_PAIR",
 839         "ARM_RELOC_SECTDIFF",
 840         "ARM_RELOC_LOCAL_SECTDIFF",
 841         "ARM_RELOC_PB_LA_PTR",
 842         "ARM_RELOC_BR24",
 843         "ARM_THUMB_RELOC_BR22",
 844         "ARM_THUMB_32BIT_BRANCH",
 845         "ARM_RELOC_HALF",
 846         "ARM_RELOC_HALF_SECTDIFF" };
 847
 848       if (r_type > 9)
 849         res = "Unknown";
 850       else
 851         res = Table[r_type];
 852       break;
 853     }
 854     case Triple::ppc: {
 855       static const char *const Table[] =  {
 856         "PPC_RELOC_VANILLA",
 857         "PPC_RELOC_PAIR",
 858         "PPC_RELOC_BR14",
 859         "PPC_RELOC_BR24",
 860         "PPC_RELOC_HI16",
 861         "PPC_RELOC_LO16",
 862         "PPC_RELOC_HA16",
 863         "PPC_RELOC_LO14",
 864         "PPC_RELOC_SECTDIFF",
 865         "PPC_RELOC_PB_LA_PTR",
 866         "PPC_RELOC_HI16_SECTDIFF",
 867         "PPC_RELOC_LO16_SECTDIFF",
 868         "PPC_RELOC_HA16_SECTDIFF",
 869         "PPC_RELOC_JBSR",
 870         "PPC_RELOC_LO14_SECTDIFF",
 871         "PPC_RELOC_LOCAL_SECTDIFF" };
 872
 873       res = Table[r_type];
 874       break;
 875     }
 876     case Triple::UnknownArch:
 877       res = "Unknown";
 878       break;
 879   }
 880   Result.append(res.begin(), res.end());
 881   return object_error::success;
 882 }
 883 error_code MachOObjectFile::getRelocationAdditionalInfo(DataRefImpl Rel,
 884                                                         int64_t &Res) const {
 885   InMemoryStruct<macho::RelocationEntry> RE;
 886   getRelocation(Rel, RE);
 887   bool isExtern = (RE->Word1 >> 27) & 1;
 888   Res = 0;
 889   if (!isExtern) {
 890     const uint8_t* sectAddress = base();
 891     if (MachOObj->is64Bit()) {
 892       InMemoryStruct<macho::Section64> Sect;
 893       getSection64(Sections[Rel.d.b], Sect);
 894       sectAddress += Sect->Offset;
 895     } else {
 896       InMemoryStruct<macho::Section> Sect;
 897       getSection(Sections[Rel.d.b], Sect);
 898       sectAddress += Sect->Offset;
 899     }
 900     Res = reinterpret_cast<uintptr_t>(sectAddress);
 901   }
 902   return object_error::success;
 903 }
 904
 905 // Helper to advance a section or symbol iterator multiple increments at a time.
 906 template<class T>
 907 error_code advance(T &it, size_t Val) {
 908   error_code ec;
 909   while (Val--) {
 910     it.increment(ec);
 911   }
 912   return ec;
 913 }
 914
 915 template<class T>
 916 void advanceTo(T &it, size_t Val) {
 917   if (error_code ec = advance(it, Val))
 918     report_fatal_error(ec.message());
 919 }
 920
 921 void MachOObjectFile::printRelocationTargetName(
 922                                      InMemoryStruct<macho::RelocationEntry>& RE,
 923                                      raw_string_ostream &fmt) const {
 924   unsigned Arch = getArch();
 925   bool isScattered = (Arch != Triple::x86_64) &&
 926                      (RE->Word0 & macho::RF_Scattered);
 927
 928   // Target of a scattered relocation is an address.  In the interest of
 929   // generating pretty output, scan through the symbol table looking for a
 930   // symbol that aligns with that address.  If we find one, print it.
 931   // Otherwise, we just print the hex address of the target.
 932   if (isScattered) {
 933     uint32_t Val = RE->Word1;
 934
 935     error_code ec;
 936     for (symbol_iterator SI = begin_symbols(), SE = end_symbols(); SI != SE;
 937         SI.increment(ec)) {
 938       if (ec) report_fatal_error(ec.message());
 939
 940       uint64_t Addr;
 941       StringRef Name;
 942
 943       if ((ec = SI->getAddress(Addr)))
 944         report_fatal_error(ec.message());
 945       if (Addr != Val) continue;
 946       if ((ec = SI->getName(Name)))
 947         report_fatal_error(ec.message());
 948       fmt << Name;
 949       return;
 950     }
 951
 952     // If we couldn't find a symbol that this relocation refers to, try
 953     // to find a section beginning instead.
 954     for (section_iterator SI = begin_sections(), SE = end_sections(); SI != SE;
 955          SI.increment(ec)) {
 956       if (ec) report_fatal_error(ec.message());
 957
 958       uint64_t Addr;
 959       StringRef Name;
 960
 961       if ((ec = SI->getAddress(Addr)))
 962         report_fatal_error(ec.message());
 963       if (Addr != Val) continue;
 964       if ((ec = SI->getName(Name)))
 965         report_fatal_error(ec.message());
 966       fmt << Name;
 967       return;
 968     }
 969
 970     fmt << format("0x%x", Val);
 971     return;
 972   }
 973
 974   StringRef S;
 975   bool isExtern = (RE->Word1 >> 27) & 1;
 976   uint32_t Val = RE->Word1 & 0xFFFFFF;
 977
 978   if (isExtern) {
 979     symbol_iterator SI = begin_symbols();
 980     advanceTo(SI, Val);
 981     SI->getName(S);
 982   } else {
 983     section_iterator SI = begin_sections();
 984     advanceTo(SI, Val);
 985     SI->getName(S);
 986   }
 987
 988   fmt << S;
 989 }
 990
 991 error_code MachOObjectFile::getRelocationValueString(DataRefImpl Rel,
 992                                           SmallVectorImpl<char> &Result) const {
 993   InMemoryStruct<macho::RelocationEntry> RE;
 994   getRelocation(Rel, RE);
 995
 996   unsigned Arch = getArch();
 997   bool isScattered = (Arch != Triple::x86_64) &&
 998                      (RE->Word0 & macho::RF_Scattered);
 999
1000   std::string fmtbuf;
1001   raw_string_ostream fmt(fmtbuf);
1002
1003   unsigned Type;
1004   if (isScattered)
1005     Type = (RE->Word0 >> 24) & 0xF;
1006   else
1007     Type = (RE->Word1 >> 28) & 0xF;
1008
1009   bool isPCRel;
1010   if (isScattered)
1011     isPCRel = ((RE->Word0 >> 30) & 1);
1012   else
1013     isPCRel = ((RE->Word1 >> 24) & 1);
1014
1015   // Determine any addends that should be displayed with the relocation.
1016   // These require decoding the relocation type, which is triple-specific.
1017
1018   // X86_64 has entirely custom relocation types.
1019   if (Arch == Triple::x86_64) {
1020     bool isPCRel = ((RE->Word1 >> 24) & 1);
1021
1022     switch (Type) {
1023       case macho::RIT_X86_64_GOTLoad:   // X86_64_RELOC_GOT_LOAD
1024       case macho::RIT_X86_64_GOT: {     // X86_64_RELOC_GOT
1025         printRelocationTargetName(RE, fmt);
1026         fmt << "@GOT";
1027         if (isPCRel) fmt << "PCREL";
1028         break;
1029       }
1030       case macho::RIT_X86_64_Subtractor: { // X86_64_RELOC_SUBTRACTOR
1031         InMemoryStruct<macho::RelocationEntry> RENext;
1032         DataRefImpl RelNext = Rel;
1033         RelNext.d.a++;
1034         getRelocation(RelNext, RENext);
1035
1036         // X86_64_SUBTRACTOR must be followed by a relocation of type
1037         // X86_64_RELOC_UNSIGNED.
1038         // NOTE: Scattered relocations don't exist on x86_64.
1039         unsigned RType = (RENext->Word1 >> 28) & 0xF;
1040         if (RType != 0)
1041           report_fatal_error("Expected X86_64_RELOC_UNSIGNED after "
1042                              "X86_64_RELOC_SUBTRACTOR.");
1043
1044         // The X86_64_RELOC_UNSIGNED contains the minuend symbol,
1045         // X86_64_SUBTRACTOR contains to the subtrahend.
1046         printRelocationTargetName(RENext, fmt);
1047         fmt << "-";
1048         printRelocationTargetName(RE, fmt);
1049       }
1050       case macho::RIT_X86_64_TLV:
1051         printRelocationTargetName(RE, fmt);
1052         fmt << "@TLV";
1053         if (isPCRel) fmt << "P";
1054         break;
1055       case macho::RIT_X86_64_Signed1: // X86_64_RELOC_SIGNED1
1056         printRelocationTargetName(RE, fmt);
1057         fmt << "-1";
1058         break;
1059       case macho::RIT_X86_64_Signed2: // X86_64_RELOC_SIGNED2
1060         printRelocationTargetName(RE, fmt);
1061         fmt << "-2";
1062         break;
1063       case macho::RIT_X86_64_Signed4: // X86_64_RELOC_SIGNED4
1064         printRelocationTargetName(RE, fmt);
1065         fmt << "-4";
1066         break;
1067       default:
1068         printRelocationTargetName(RE, fmt);
1069         break;
1070     }
1071   // X86 and ARM share some relocation types in common.
1072   } else if (Arch == Triple::x86 || Arch == Triple::arm) {
1073     // Generic relocation types...
1074     switch (Type) {
1075       case macho::RIT_Pair: // GENERIC_RELOC_PAIR - prints no info
1076         return object_error::success;
1077       case macho::RIT_Difference: { // GENERIC_RELOC_SECTDIFF
1078         InMemoryStruct<macho::RelocationEntry> RENext;
1079         DataRefImpl RelNext = Rel;
1080         RelNext.d.a++;
1081         getRelocation(RelNext, RENext);
1082
1083         // X86 sect diff's must be followed by a relocation of type
1084         // GENERIC_RELOC_PAIR.
1085         bool isNextScattered = (Arch != Triple::x86_64) &&
1086                                (RENext->Word0 & macho::RF_Scattered);
1087         unsigned RType;
1088         if (isNextScattered)
1089           RType = (RENext->Word0 >> 24) & 0xF;
1090         else
1091           RType = (RENext->Word1 >> 28) & 0xF;
1092         if (RType != 1)
1093           report_fatal_error("Expected GENERIC_RELOC_PAIR after "
1094                              "GENERIC_RELOC_SECTDIFF.");
1095
1096         printRelocationTargetName(RE, fmt);
1097         fmt << "-";
1098         printRelocationTargetName(RENext, fmt);
1099         break;
1100       }
1101     }
1102
1103     if (Arch == Triple::x86) {
1104       // All X86 relocations that need special printing were already
1105       // handled in the generic code.
1106       switch (Type) {
1107         case macho::RIT_Generic_LocalDifference:{// GENERIC_RELOC_LOCAL_SECTDIFF
1108           InMemoryStruct<macho::RelocationEntry> RENext;
1109           DataRefImpl RelNext = Rel;
1110           RelNext.d.a++;
1111           getRelocation(RelNext, RENext);
1112
1113           // X86 sect diff's must be followed by a relocation of type
1114           // GENERIC_RELOC_PAIR.
1115           bool isNextScattered = (Arch != Triple::x86_64) &&
1116                                (RENext->Word0 & macho::RF_Scattered);
1117           unsigned RType;
1118           if (isNextScattered)
1119             RType = (RENext->Word0 >> 24) & 0xF;
1120           else
1121             RType = (RENext->Word1 >> 28) & 0xF;
1122           if (RType != 1)
1123             report_fatal_error("Expected GENERIC_RELOC_PAIR after "
1124                                "GENERIC_RELOC_LOCAL_SECTDIFF.");
1125
1126           printRelocationTargetName(RE, fmt);
1127           fmt << "-";
1128           printRelocationTargetName(RENext, fmt);
1129           break;
1130         }
1131         case macho::RIT_Generic_TLV: {
1132           printRelocationTargetName(RE, fmt);
1133           fmt << "@TLV";
1134           if (isPCRel) fmt << "P";
1135           break;
1136         }
1137         default:
1138           printRelocationTargetName(RE, fmt);
1139       }
1140     } else { // ARM-specific relocations
1141       switch (Type) {
1142         case macho::RIT_ARM_Half:             // ARM_RELOC_HALF
1143         case macho::RIT_ARM_HalfDifference: { // ARM_RELOC_HALF_SECTDIFF
1144           // Half relocations steal a bit from the length field to encode
1145           // whether this is an upper16 or a lower16 relocation.
1146           bool isUpper;
1147           if (isScattered)
1148             isUpper = (RE->Word0 >> 28) & 1;
1149           else
1150             isUpper = (RE->Word1 >> 25) & 1;
1151
1152           if (isUpper)
1153             fmt << ":upper16:(";
1154           else
1155             fmt << ":lower16:(";
1156           printRelocationTargetName(RE, fmt);
1157
1158           InMemoryStruct<macho::RelocationEntry> RENext;
1159           DataRefImpl RelNext = Rel;
1160           RelNext.d.a++;
1161           getRelocation(RelNext, RENext);
1162
1163           // ARM half relocs must be followed by a relocation of type
1164           // ARM_RELOC_PAIR.
1165           bool isNextScattered = (Arch != Triple::x86_64) &&
1166                                  (RENext->Word0 & macho::RF_Scattered);
1167           unsigned RType;
1168           if (isNextScattered)
1169             RType = (RENext->Word0 >> 24) & 0xF;
1170           else
1171             RType = (RENext->Word1 >> 28) & 0xF;
1172
1173           if (RType != 1)
1174             report_fatal_error("Expected ARM_RELOC_PAIR after "
1175                                "GENERIC_RELOC_HALF");
1176
1177           // NOTE: The half of the target virtual address is stashed in the
1178           // address field of the secondary relocation, but we can't reverse
1179           // engineer the constant offset from it without decoding the movw/movt
1180           // instruction to find the other half in its immediate field.
1181
1182           // ARM_RELOC_HALF_SECTDIFF encodes the second section in the
1183           // symbol/section pointer of the follow-on relocation.
1184           if (Type == macho::RIT_ARM_HalfDifference) {
1185             fmt << "-";
1186             printRelocationTargetName(RENext, fmt);
1187           }
1188
1189           fmt << ")";
1190           break;
1191         }
1192         default: {
1193           printRelocationTargetName(RE, fmt);
1194         }
1195       }
1196     }
1197   } else
1198     printRelocationTargetName(RE, fmt);
1199
1200   fmt.flush();
1201   Result.append(fmtbuf.begin(), fmtbuf.end());
1202   return object_error::success;
1203 }
1204
1205 error_code MachOObjectFile::getRelocationHidden(DataRefImpl Rel,
1206                                                 bool &Result) const {
1207   InMemoryStruct<macho::RelocationEntry> RE;
1208   getRelocation(Rel, RE);
1209
1210   unsigned Arch = getArch();
1211   bool isScattered = (Arch != Triple::x86_64) &&
1212                      (RE->Word0 & macho::RF_Scattered);
1213   unsigned Type;
1214   if (isScattered)
1215     Type = (RE->Word0 >> 24) & 0xF;
1216   else
1217     Type = (RE->Word1 >> 28) & 0xF;
1218
1219   Result = false;
1220
1221   // On arches that use the generic relocations, GENERIC_RELOC_PAIR
1222   // is always hidden.
1223   if (Arch == Triple::x86 || Arch == Triple::arm) {
1224     if (Type == macho::RIT_Pair) Result = true;
1225   } else if (Arch == Triple::x86_64) {
1226     // On x86_64, X86_64_RELOC_UNSIGNED is hidden only when it follows
1227     // an X864_64_RELOC_SUBTRACTOR.
1228     if (Type == macho::RIT_X86_64_Unsigned && Rel.d.a > 0) {
1229       DataRefImpl RelPrev = Rel;
1230       RelPrev.d.a--;
1231       InMemoryStruct<macho::RelocationEntry> REPrev;
1232       getRelocation(RelPrev, REPrev);
1233
1234       unsigned PrevType = (REPrev->Word1 >> 28) & 0xF;
1235
1236       if (PrevType == macho::RIT_X86_64_Subtractor) Result = true;
1237     }
1238   }
1239
1240   return object_error::success;
1241 }
1242
1243 error_code MachOObjectFile::getLibraryNext(DataRefImpl LibData,
1244                                            LibraryRef &Res) const {
1245   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1246 }
1247
1248 error_code MachOObjectFile::getLibraryPath(DataRefImpl LibData,
1249                                            StringRef &Res) const {
1250   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1251 }
1252
1253
1254 /*===-- Miscellaneous -----------------------------------------------------===*/
1255
1256 uint8_t MachOObjectFile::getBytesInAddress() const {
1257   return MachOObj->is64Bit() ? 8 : 4;
1258 }
1259
1260 StringRef MachOObjectFile::getFileFormatName() const {
1261   if (!MachOObj->is64Bit()) {
1262     switch (MachOObj->getHeader().CPUType) {
1263     case llvm::MachO::CPUTypeI386:
1264       return "Mach-O 32-bit i386";
1265     case llvm::MachO::CPUTypeARM:
1266       return "Mach-O arm";
1267     case llvm::MachO::CPUTypePowerPC:
1268       return "Mach-O 32-bit ppc";
1269     default:
1270       assert((MachOObj->getHeader().CPUType & llvm::MachO::CPUArchABI64) == 0 &&
1271              "64-bit object file when we're not 64-bit?");
1272       return "Mach-O 32-bit unknown";
1273     }
1274   }
1275
1276   switch (MachOObj->getHeader().CPUType) {
1277   case llvm::MachO::CPUTypeX86_64:
1278     return "Mach-O 64-bit x86-64";
1279   case llvm::MachO::CPUTypePowerPC64:
1280     return "Mach-O 64-bit ppc64";
1281   default:
1282     assert((MachOObj->getHeader().CPUType & llvm::MachO::CPUArchABI64) == 1 &&
1283            "32-bit object file when we're 64-bit?");
1284     return "Mach-O 64-bit unknown";
1285   }
1286 }
1287
1288 unsigned MachOObjectFile::getArch() const {
1289   switch (MachOObj->getHeader().CPUType) {
1290   case llvm::MachO::CPUTypeI386:
1291     return Triple::x86;
1292   case llvm::MachO::CPUTypeX86_64:
1293     return Triple::x86_64;
1294   case llvm::MachO::CPUTypeARM:
1295     return Triple::arm;
1296   case llvm::MachO::CPUTypePowerPC:
1297     return Triple::ppc;
1298   case llvm::MachO::CPUTypePowerPC64:
1299     return Triple::ppc64;
1300   default:
1301     return Triple::UnknownArch;
1302   }
1303 }
1304
1305 } // end namespace object
1306 } // end namespace llvm