xref: /llvm-project/llvm/lib/Object/MachOObjectFile.cpp (revision 3cdeb17ff2515e4a1e331cc0eda8a886eceaf1c7) 
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/Object/MachO.h"
16 #include "llvm/ADT/Triple.h"
17 #include "llvm/Object/MachOFormat.h"
18 #include "llvm/Support/DataExtractor.h"
19 #include "llvm/Support/Format.h"
20 #include "llvm/Support/Host.h"
21 #include "llvm/Support/MemoryBuffer.h"
22 #include <cctype>
23 #include <cstring>
24 #include <limits>
25 
26 using namespace llvm;
27 using namespace object;
28 
29 namespace llvm {
30 namespace object {
31 
32 struct SymbolTableEntryBase {
33   uint32_t StringIndex;
34   uint8_t Type;
35   uint8_t SectionIndex;
36   uint16_t Flags;
37 };
38 
39 struct SectionBase {
40   char Name[16];
41   char SegmentName[16];
42 };
43 
44 template<typename T>
45 static void SwapValue(T &Value) {
46   Value = sys::SwapByteOrder(Value);
47 }
48 
49 template<typename T>
50 static void SwapStruct(T &Value);
51 
52 template<>
53 void SwapStruct(macho::RelocationEntry &H) {
54   SwapValue(H.Word0);
55   SwapValue(H.Word1);
56 }
57 
58 template<>
59 void SwapStruct(macho::LoadCommand &L) {
60   SwapValue(L.Type);
61   SwapValue(L.Size);
62 }
63 
64 template<>
65 void SwapStruct(SymbolTableEntryBase &S) {
66   SwapValue(S.StringIndex);
67   SwapValue(S.Flags);
68 }
69 
70 template<>
71 void SwapStruct(macho::Section &S) {
72   SwapValue(S.Address);
73   SwapValue(S.Size);
74   SwapValue(S.Offset);
75   SwapValue(S.Align);
76   SwapValue(S.RelocationTableOffset);
77   SwapValue(S.NumRelocationTableEntries);
78   SwapValue(S.Flags);
79   SwapValue(S.Reserved1);
80   SwapValue(S.Reserved2);
81 }
82 
83 template<>
84 void SwapStruct(macho::Section64 &S) {
85   SwapValue(S.Address);
86   SwapValue(S.Size);
87   SwapValue(S.Offset);
88   SwapValue(S.Align);
89   SwapValue(S.RelocationTableOffset);
90   SwapValue(S.NumRelocationTableEntries);
91   SwapValue(S.Flags);
92   SwapValue(S.Reserved1);
93   SwapValue(S.Reserved2);
94   SwapValue(S.Reserved3);
95 }
96 
97 template<>
98 void SwapStruct(macho::SymbolTableEntry &S) {
99   SwapValue(S.StringIndex);
100   SwapValue(S.Flags);
101   SwapValue(S.Value);
102 }
103 
104 template<>
105 void SwapStruct(macho::Symbol64TableEntry &S) {
106   SwapValue(S.StringIndex);
107   SwapValue(S.Flags);
108   SwapValue(S.Value);
109 }
110 
111 template<>
112 void SwapStruct(macho::Header &H) {
113   SwapValue(H.Magic);
114   SwapValue(H.CPUType);
115   SwapValue(H.CPUSubtype);
116   SwapValue(H.FileType);
117   SwapValue(H.NumLoadCommands);
118   SwapValue(H.SizeOfLoadCommands);
119   SwapValue(H.Flags);
120 }
121 
122 template<>
123 void SwapStruct(macho::SymtabLoadCommand &C) {
124   SwapValue(C.Type);
125   SwapValue(C.Size);
126   SwapValue(C.SymbolTableOffset);
127   SwapValue(C.NumSymbolTableEntries);
128   SwapValue(C.StringTableOffset);
129   SwapValue(C.StringTableSize);
130 }
131 
132 template<>
133 void SwapStruct(macho::LinkeditDataLoadCommand &C) {
134   SwapValue(C.Type);
135   SwapValue(C.Size);
136   SwapValue(C.DataOffset);
137   SwapValue(C.DataSize);
138 }
139 
140 template<>
141 void SwapStruct(macho::SegmentLoadCommand &C) {
142   SwapValue(C.Type);
143   SwapValue(C.Size);
144   SwapValue(C.VMAddress);
145   SwapValue(C.VMSize);
146   SwapValue(C.FileOffset);
147   SwapValue(C.FileSize);
148   SwapValue(C.MaxVMProtection);
149   SwapValue(C.InitialVMProtection);
150   SwapValue(C.NumSections);
151   SwapValue(C.Flags);
152 }
153 
154 template<>
155 void SwapStruct(macho::Segment64LoadCommand &C) {
156   SwapValue(C.Type);
157   SwapValue(C.Size);
158   SwapValue(C.VMAddress);
159   SwapValue(C.VMSize);
160   SwapValue(C.FileOffset);
161   SwapValue(C.FileSize);
162   SwapValue(C.MaxVMProtection);
163   SwapValue(C.InitialVMProtection);
164   SwapValue(C.NumSections);
165   SwapValue(C.Flags);
166 }
167 
168 template<typename T>
169 T getStruct(const MachOObjectFile *O, const char *P) {
170   T Cmd;
171   memcpy(&Cmd, P, sizeof(T));
172   if (O->isLittleEndian() != sys::IsLittleEndianHost)
173     SwapStruct(Cmd);
174   return Cmd;
175 }
176 
177 static macho::SegmentLoadCommand
178 getSegmentLoadCommand(const MachOObjectFile *O,
179                       const MachOObjectFile::LoadCommandInfo &L) {
180   return getStruct<macho::SegmentLoadCommand>(O, L.Ptr);
181 }
182 
183 static macho::Segment64LoadCommand
184 getSegment64LoadCommand(const MachOObjectFile *O,
185                         const MachOObjectFile::LoadCommandInfo &L) {
186   return getStruct<macho::Segment64LoadCommand>(O, L.Ptr);
187 }
188 
189 static uint32_t
190 getSegmentLoadCommandNumSections(const MachOObjectFile *O,
191                                  const MachOObjectFile::LoadCommandInfo &L) {
192   if (O->is64Bit()) {
193     macho::Segment64LoadCommand S = getSegment64LoadCommand(O, L);
194     return S.NumSections;
195   }
196   macho::SegmentLoadCommand S = getSegmentLoadCommand(O, L);
197   return S.NumSections;
198 }
199 
200 static const SectionBase *
201 getSectionBase(const MachOObjectFile *O, MachOObjectFile::LoadCommandInfo L,
202                unsigned Sec) {
203   uintptr_t CommandAddr = reinterpret_cast<uintptr_t>(L.Ptr);
204 
205   bool Is64 = O->is64Bit();
206   unsigned SegmentLoadSize = Is64 ? sizeof(macho::Segment64LoadCommand) :
207                                     sizeof(macho::SegmentLoadCommand);
208   unsigned SectionSize = Is64 ? sizeof(macho::Section64) :
209                                 sizeof(macho::Section);
210 
211   uintptr_t SectionAddr = CommandAddr + SegmentLoadSize + Sec * SectionSize;
212   return reinterpret_cast<const SectionBase*>(SectionAddr);
213 }
214 
215 static const char *getPtr(const MachOObjectFile *O, size_t Offset) {
216   return O->getData().substr(Offset, 1).data();
217 }
218 
219 static const char *getSymbolTableEntryPtr(const MachOObjectFile *O,
220                                           DataRefImpl DRI) {
221   macho::SymtabLoadCommand S = O->getSymtabLoadCommand();
222 
223   unsigned Index = DRI.d.b;
224 
225   unsigned SymbolTableEntrySize = O->is64Bit() ?
226     sizeof(macho::Symbol64TableEntry) :
227     sizeof(macho::SymbolTableEntry);
228 
229   uint64_t Offset = S.SymbolTableOffset + Index * SymbolTableEntrySize;
230   return getPtr(O, Offset);
231 }
232 
233 static SymbolTableEntryBase
234 getSymbolTableEntryBase(const MachOObjectFile *O, DataRefImpl DRI) {
235   const char *P = getSymbolTableEntryPtr(O, DRI);
236   return getStruct<SymbolTableEntryBase>(O, P);
237 }
238 
239 static StringRef parseSegmentOrSectionName(const char *P) {
240   if (P[15] == 0)
241     // Null terminated.
242     return P;
243   // Not null terminated, so this is a 16 char string.
244   return StringRef(P, 16);
245 }
246 
247 // Helper to advance a section or symbol iterator multiple increments at a time.
248 template<class T>
249 static error_code advance(T &it, size_t Val) {
250   error_code ec;
251   while (Val--) {
252     it.increment(ec);
253   }
254   return ec;
255 }
256 
257 template<class T>
258 static void advanceTo(T &it, size_t Val) {
259   if (error_code ec = advance(it, Val))
260     report_fatal_error(ec.message());
261 }
262 
263 static unsigned getCPUType(const MachOObjectFile *O) {
264   return O->getHeader().CPUType;
265 }
266 
267 static void printRelocationTargetName(const MachOObjectFile *O,
268                                       const macho::RelocationEntry &RE,
269                                       raw_string_ostream &fmt) {
270   bool IsScattered = O->isRelocationScattered(RE);
271 
272   // Target of a scattered relocation is an address.  In the interest of
273   // generating pretty output, scan through the symbol table looking for a
274   // symbol that aligns with that address.  If we find one, print it.
275   // Otherwise, we just print the hex address of the target.
276   if (IsScattered) {
277     uint32_t Val = O->getPlainRelocationSymbolNum(RE);
278 
279     error_code ec;
280     for (symbol_iterator SI = O->begin_symbols(), SE = O->end_symbols();
281          SI != SE; SI.increment(ec)) {
282       if (ec) report_fatal_error(ec.message());
283 
284       uint64_t Addr;
285       StringRef Name;
286 
287       if ((ec = SI->getAddress(Addr)))
288         report_fatal_error(ec.message());
289       if (Addr != Val) continue;
290       if ((ec = SI->getName(Name)))
291         report_fatal_error(ec.message());
292       fmt << Name;
293       return;
294     }
295 
296     // If we couldn't find a symbol that this relocation refers to, try
297     // to find a section beginning instead.
298     for (section_iterator SI = O->begin_sections(), SE = O->end_sections();
299          SI != SE; SI.increment(ec)) {
300       if (ec) report_fatal_error(ec.message());
301 
302       uint64_t Addr;
303       StringRef Name;
304 
305       if ((ec = SI->getAddress(Addr)))
306         report_fatal_error(ec.message());
307       if (Addr != Val) continue;
308       if ((ec = SI->getName(Name)))
309         report_fatal_error(ec.message());
310       fmt << Name;
311       return;
312     }
313 
314     fmt << format("0x%x", Val);
315     return;
316   }
317 
318   StringRef S;
319   bool isExtern = O->getPlainRelocationExternal(RE);
320   uint64_t Val = O->getAnyRelocationAddress(RE);
321 
322   if (isExtern) {
323     symbol_iterator SI = O->begin_symbols();
324     advanceTo(SI, Val);
325     SI->getName(S);
326   } else {
327     section_iterator SI = O->begin_sections();
328     advanceTo(SI, Val);
329     SI->getName(S);
330   }
331 
332   fmt << S;
333 }
334 
335 static uint32_t getPlainRelocationAddress(const macho::RelocationEntry &RE) {
336   return RE.Word0;
337 }
338 
339 static unsigned
340 getScatteredRelocationAddress(const macho::RelocationEntry &RE) {
341   return RE.Word0 & 0xffffff;
342 }
343 
344 static bool getPlainRelocationPCRel(const MachOObjectFile *O,
345                                     const macho::RelocationEntry &RE) {
346   if (O->isLittleEndian())
347     return (RE.Word1 >> 24) & 1;
348   return (RE.Word1 >> 7) & 1;
349 }
350 
351 static bool
352 getScatteredRelocationPCRel(const MachOObjectFile *O,
353                             const macho::RelocationEntry &RE) {
354   return (RE.Word0 >> 30) & 1;
355 }
356 
357 static unsigned getPlainRelocationLength(const MachOObjectFile *O,
358                                          const macho::RelocationEntry &RE) {
359   if (O->isLittleEndian())
360     return (RE.Word1 >> 25) & 3;
361   return (RE.Word1 >> 5) & 3;
362 }
363 
364 static unsigned
365 getScatteredRelocationLength(const macho::RelocationEntry &RE) {
366   return (RE.Word0 >> 28) & 3;
367 }
368 
369 static unsigned getPlainRelocationType(const MachOObjectFile *O,
370                                        const macho::RelocationEntry &RE) {
371   if (O->isLittleEndian())
372     return RE.Word1 >> 28;
373   return RE.Word1 & 0xf;
374 }
375 
376 static unsigned getScatteredRelocationType(const macho::RelocationEntry &RE) {
377   return (RE.Word0 >> 24) & 0xf;
378 }
379 
380 static uint32_t getSectionFlags(const MachOObjectFile *O,
381                                 DataRefImpl Sec) {
382   if (O->is64Bit()) {
383     macho::Section64 Sect = O->getSection64(Sec);
384     return Sect.Flags;
385   }
386   macho::Section Sect = O->getSection(Sec);
387   return Sect.Flags;
388 }
389 
390 MachOObjectFile::MachOObjectFile(MemoryBuffer *Object,
391                                  bool IsLittleEndian, bool Is64bits,
392                                  error_code &ec)
393     : ObjectFile(getMachOType(IsLittleEndian, Is64bits), Object),
394       SymtabLoadCmd(NULL) {
395   uint32_t LoadCommandCount = this->getHeader().NumLoadCommands;
396   macho::LoadCommandType SegmentLoadType = is64Bit() ?
397     macho::LCT_Segment64 : macho::LCT_Segment;
398 
399   MachOObjectFile::LoadCommandInfo Load = getFirstLoadCommandInfo();
400   for (unsigned I = 0; ; ++I) {
401     if (Load.C.Type == macho::LCT_Symtab) {
402       assert(!SymtabLoadCmd && "Multiple symbol tables");
403       SymtabLoadCmd = Load.Ptr;
404     }
405 
406     if (Load.C.Type == SegmentLoadType) {
407       uint32_t NumSections = getSegmentLoadCommandNumSections(this, Load);
408       for (unsigned J = 0; J < NumSections; ++J) {
409         const SectionBase *Sec = getSectionBase(this, Load, J);
410         Sections.push_back(reinterpret_cast<const char*>(Sec));
411       }
412     }
413 
414     if (I == LoadCommandCount - 1)
415       break;
416     else
417       Load = getNextLoadCommandInfo(Load);
418   }
419 }
420 
421 error_code MachOObjectFile::getSymbolNext(DataRefImpl Symb,
422                                           SymbolRef &Res) const {
423   Symb.d.b++;
424   Res = SymbolRef(Symb, this);
425   return object_error::success;
426 }
427 
428 error_code MachOObjectFile::getSymbolName(DataRefImpl Symb,
429                                           StringRef &Res) const {
430   macho::SymtabLoadCommand S = getSymtabLoadCommand();
431   const char *StringTable = getPtr(this, S.StringTableOffset);
432   SymbolTableEntryBase Entry = getSymbolTableEntryBase(this, Symb);
433   const char *Start = &StringTable[Entry.StringIndex];
434   Res = StringRef(Start);
435   return object_error::success;
436 }
437 
438 error_code MachOObjectFile::getSymbolAddress(DataRefImpl Symb,
439                                              uint64_t &Res) const {
440   if (is64Bit()) {
441     macho::Symbol64TableEntry Entry = getSymbol64TableEntry(Symb);
442     Res = Entry.Value;
443   } else {
444     macho::SymbolTableEntry Entry = getSymbolTableEntry(Symb);
445     Res = Entry.Value;
446   }
447   return object_error::success;
448 }
449 
450 error_code
451 MachOObjectFile::getSymbolFileOffset(DataRefImpl Symb,
452                                      uint64_t &Res) const {
453   SymbolTableEntryBase Entry = getSymbolTableEntryBase(this, Symb);
454   getSymbolAddress(Symb, Res);
455   if (Entry.SectionIndex) {
456     uint64_t Delta;
457     DataRefImpl SecRel;
458     SecRel.d.a = Entry.SectionIndex-1;
459     if (is64Bit()) {
460       macho::Section64 Sec = getSection64(SecRel);
461       Delta = Sec.Offset - Sec.Address;
462     } else {
463       macho::Section Sec = getSection(SecRel);
464       Delta = Sec.Offset - Sec.Address;
465     }
466 
467     Res += Delta;
468   }
469 
470   return object_error::success;
471 }
472 
473 error_code MachOObjectFile::getSymbolSize(DataRefImpl DRI,
474                                           uint64_t &Result) const {
475   uint64_t BeginOffset;
476   uint64_t EndOffset = 0;
477   uint8_t SectionIndex;
478 
479   SymbolTableEntryBase Entry = getSymbolTableEntryBase(this, DRI);
480   uint64_t Value;
481   getSymbolAddress(DRI, Value);
482 
483   BeginOffset = Value;
484 
485   SectionIndex = Entry.SectionIndex;
486   if (!SectionIndex) {
487     uint32_t flags = SymbolRef::SF_None;
488     this->getSymbolFlags(DRI, flags);
489     if (flags & SymbolRef::SF_Common)
490       Result = Value;
491     else
492       Result = UnknownAddressOrSize;
493     return object_error::success;
494   }
495   // Unfortunately symbols are unsorted so we need to touch all
496   // symbols from load command
497   macho::SymtabLoadCommand Symtab = getSymtabLoadCommand();
498   DRI.d.b = 0;
499   while (DRI.d.b <= Symtab.NumSymbolTableEntries) {
500     Entry = getSymbolTableEntryBase(this, DRI);
501     getSymbolAddress(DRI, Value);
502     if (Entry.SectionIndex == SectionIndex && Value > BeginOffset)
503       if (!EndOffset || Value < EndOffset)
504         EndOffset = Value;
505     DRI.d.b++;
506   }
507   if (!EndOffset) {
508     uint64_t Size;
509     DataRefImpl Sec;
510     Sec.d.a = SectionIndex-1;
511     getSectionSize(Sec, Size);
512     getSectionAddress(Sec, EndOffset);
513     EndOffset += Size;
514   }
515   Result = EndOffset - BeginOffset;
516   return object_error::success;
517 }
518 
519 error_code MachOObjectFile::getSymbolType(DataRefImpl Symb,
520                                           SymbolRef::Type &Res) const {
521   SymbolTableEntryBase Entry = getSymbolTableEntryBase(this, Symb);
522   uint8_t n_type = Entry.Type;
523 
524   Res = SymbolRef::ST_Other;
525 
526   // If this is a STAB debugging symbol, we can do nothing more.
527   if (n_type & MachO::NlistMaskStab) {
528     Res = SymbolRef::ST_Debug;
529     return object_error::success;
530   }
531 
532   switch (n_type & MachO::NlistMaskType) {
533     case MachO::NListTypeUndefined :
534       Res = SymbolRef::ST_Unknown;
535       break;
536     case MachO::NListTypeSection :
537       Res = SymbolRef::ST_Function;
538       break;
539   }
540   return object_error::success;
541 }
542 
543 error_code MachOObjectFile::getSymbolNMTypeChar(DataRefImpl Symb,
544                                                 char &Res) const {
545   SymbolTableEntryBase Entry = getSymbolTableEntryBase(this, Symb);
546   uint8_t Type = Entry.Type;
547   uint16_t Flags = Entry.Flags;
548 
549   char Char;
550   switch (Type & macho::STF_TypeMask) {
551     case macho::STT_Undefined:
552       Char = 'u';
553       break;
554     case macho::STT_Absolute:
555     case macho::STT_Section:
556       Char = 's';
557       break;
558     default:
559       Char = '?';
560       break;
561   }
562 
563   if (Flags & (macho::STF_External | macho::STF_PrivateExtern))
564     Char = toupper(static_cast<unsigned char>(Char));
565   Res = Char;
566   return object_error::success;
567 }
568 
569 error_code MachOObjectFile::getSymbolFlags(DataRefImpl DRI,
570                                            uint32_t &Result) const {
571   SymbolTableEntryBase Entry = getSymbolTableEntryBase(this, DRI);
572 
573   uint8_t MachOType = Entry.Type;
574   uint16_t MachOFlags = Entry.Flags;
575 
576   // TODO: Correctly set SF_ThreadLocal
577   Result = SymbolRef::SF_None;
578 
579   if ((MachOType & MachO::NlistMaskType) == MachO::NListTypeUndefined)
580     Result |= SymbolRef::SF_Undefined;
581 
582   if (MachOFlags & macho::STF_StabsEntryMask)
583     Result |= SymbolRef::SF_FormatSpecific;
584 
585   if (MachOType & MachO::NlistMaskExternal) {
586     Result |= SymbolRef::SF_Global;
587     if ((MachOType & MachO::NlistMaskType) == MachO::NListTypeUndefined)
588       Result |= SymbolRef::SF_Common;
589   }
590 
591   if (MachOFlags & (MachO::NListDescWeakRef | MachO::NListDescWeakDef))
592     Result |= SymbolRef::SF_Weak;
593 
594   if ((MachOType & MachO::NlistMaskType) == MachO::NListTypeAbsolute)
595     Result |= SymbolRef::SF_Absolute;
596 
597   return object_error::success;
598 }
599 
600 error_code
601 MachOObjectFile::getSymbolSection(DataRefImpl Symb,
602                                   section_iterator &Res) const {
603   SymbolTableEntryBase Entry = getSymbolTableEntryBase(this, Symb);
604   uint8_t index = Entry.SectionIndex;
605 
606   if (index == 0) {
607     Res = end_sections();
608   } else {
609     DataRefImpl DRI;
610     DRI.d.a = index - 1;
611     Res = section_iterator(SectionRef(DRI, this));
612   }
613 
614   return object_error::success;
615 }
616 
617 error_code MachOObjectFile::getSymbolValue(DataRefImpl Symb,
618                                                uint64_t &Val) const {
619   report_fatal_error("getSymbolValue unimplemented in MachOObjectFile");
620 }
621 
622 error_code MachOObjectFile::getSectionNext(DataRefImpl Sec,
623                                            SectionRef &Res) const {
624   Sec.d.a++;
625   Res = SectionRef(Sec, this);
626   return object_error::success;
627 }
628 
629 error_code
630 MachOObjectFile::getSectionName(DataRefImpl Sec,
631                                     StringRef &Result) const {
632   ArrayRef<char> Raw = getSectionRawName(Sec);
633   Result = parseSegmentOrSectionName(Raw.data());
634   return object_error::success;
635 }
636 
637 error_code
638 MachOObjectFile::getSectionAddress(DataRefImpl Sec,
639                                    uint64_t &Res) const {
640   if (is64Bit()) {
641     macho::Section64 Sect = getSection64(Sec);
642     Res = Sect.Address;
643   } else {
644     macho::Section Sect = getSection(Sec);
645     Res = Sect.Address;
646   }
647   return object_error::success;
648 }
649 
650 error_code
651 MachOObjectFile::getSectionSize(DataRefImpl Sec,
652                                 uint64_t &Res) const {
653   if (is64Bit()) {
654     macho::Section64 Sect = getSection64(Sec);
655     Res = Sect.Size;
656   } else {
657     macho::Section Sect = getSection(Sec);
658     Res = Sect.Size;
659   }
660 
661   return object_error::success;
662 }
663 
664 error_code
665 MachOObjectFile::getSectionContents(DataRefImpl Sec,
666                                     StringRef &Res) const {
667   uint32_t Offset;
668   uint64_t Size;
669 
670   if (is64Bit()) {
671     macho::Section64 Sect = getSection64(Sec);
672     Offset = Sect.Offset;
673     Size = Sect.Size;
674   } else {
675     macho::Section Sect =getSection(Sec);
676     Offset = Sect.Offset;
677     Size = Sect.Size;
678   }
679 
680   Res = this->getData().substr(Offset, Size);
681   return object_error::success;
682 }
683 
684 error_code
685 MachOObjectFile::getSectionAlignment(DataRefImpl Sec,
686                                          uint64_t &Res) const {
687   uint32_t Align;
688   if (is64Bit()) {
689     macho::Section64 Sect = getSection64(Sec);
690     Align = Sect.Align;
691   } else {
692     macho::Section Sect = getSection(Sec);
693     Align = Sect.Align;
694   }
695 
696   Res = uint64_t(1) << Align;
697   return object_error::success;
698 }
699 
700 error_code
701 MachOObjectFile::isSectionText(DataRefImpl Sec, bool &Res) const {
702   uint32_t Flags = getSectionFlags(this, Sec);
703   Res = Flags & macho::SF_PureInstructions;
704   return object_error::success;
705 }
706 
707 error_code MachOObjectFile::isSectionData(DataRefImpl DRI,
708                                               bool &Result) const {
709   // FIXME: Unimplemented.
710   Result = false;
711   return object_error::success;
712 }
713 
714 error_code MachOObjectFile::isSectionBSS(DataRefImpl DRI,
715                                              bool &Result) const {
716   // FIXME: Unimplemented.
717   Result = false;
718   return object_error::success;
719 }
720 
721 error_code
722 MachOObjectFile::isSectionRequiredForExecution(DataRefImpl Sec,
723                                                    bool &Result) const {
724   // FIXME: Unimplemented.
725   Result = true;
726   return object_error::success;
727 }
728 
729 error_code MachOObjectFile::isSectionVirtual(DataRefImpl Sec,
730                                                  bool &Result) const {
731   // FIXME: Unimplemented.
732   Result = false;
733   return object_error::success;
734 }
735 
736 error_code
737 MachOObjectFile::isSectionZeroInit(DataRefImpl Sec, bool &Res) const {
738   uint32_t Flags = getSectionFlags(this, Sec);
739   unsigned SectionType = Flags & MachO::SectionFlagMaskSectionType;
740   Res = SectionType == MachO::SectionTypeZeroFill ||
741     SectionType == MachO::SectionTypeZeroFillLarge;
742   return object_error::success;
743 }
744 
745 error_code MachOObjectFile::isSectionReadOnlyData(DataRefImpl Sec,
746                                                       bool &Result) const {
747   // Consider using the code from isSectionText to look for __const sections.
748   // Alternately, emit S_ATTR_PURE_INSTRUCTIONS and/or S_ATTR_SOME_INSTRUCTIONS
749   // to use section attributes to distinguish code from data.
750 
751   // FIXME: Unimplemented.
752   Result = false;
753   return object_error::success;
754 }
755 
756 error_code
757 MachOObjectFile::sectionContainsSymbol(DataRefImpl Sec,
758                                        DataRefImpl Symb,
759                                        bool &Result) const {
760   SymbolRef::Type ST;
761   this->getSymbolType(Symb, ST);
762   if (ST == SymbolRef::ST_Unknown) {
763     Result = false;
764     return object_error::success;
765   }
766 
767   uint64_t SectBegin, SectEnd;
768   getSectionAddress(Sec, SectBegin);
769   getSectionSize(Sec, SectEnd);
770   SectEnd += SectBegin;
771 
772   uint64_t SymAddr;
773   getSymbolAddress(Symb, SymAddr);
774   Result = (SymAddr >= SectBegin) && (SymAddr < SectEnd);
775 
776   return object_error::success;
777 }
778 
779 relocation_iterator MachOObjectFile::getSectionRelBegin(DataRefImpl Sec) const {
780   DataRefImpl ret;
781   ret.d.b = Sec.d.a;
782   return relocation_iterator(RelocationRef(ret, this));
783 }
784 
785 relocation_iterator
786 MachOObjectFile::getSectionRelEnd(DataRefImpl Sec) const {
787   uint32_t LastReloc;
788   if (is64Bit()) {
789     macho::Section64 Sect = getSection64(Sec);
790     LastReloc = Sect.NumRelocationTableEntries;
791   } else {
792     macho::Section Sect = getSection(Sec);
793     LastReloc = Sect.NumRelocationTableEntries;
794   }
795 
796   DataRefImpl Ret;
797   Ret.d.a = LastReloc;
798   Ret.d.b = Sec.d.a;
799   return relocation_iterator(RelocationRef(Ret, this));
800 }
801 
802 error_code MachOObjectFile::getRelocationNext(DataRefImpl Rel,
803                                                   RelocationRef &Res) const {
804   ++Rel.d.a;
805   Res = RelocationRef(Rel, this);
806   return object_error::success;
807 }
808 
809 error_code
810 MachOObjectFile::getRelocationAddress(DataRefImpl Rel,
811                                       uint64_t &Res) const {
812   uint64_t SectAddress;
813   DataRefImpl Sec;
814   Sec.d.a = Rel.d.b;
815   if (is64Bit()) {
816     macho::Section64 Sect = getSection64(Sec);
817     SectAddress = Sect.Address;
818   } else {
819     macho::Section Sect = getSection(Sec);
820     SectAddress = Sect.Address;
821   }
822 
823   macho::RelocationEntry RE = getRelocation(Rel);
824   uint64_t RelAddr = getAnyRelocationAddress(RE);
825   Res = SectAddress + RelAddr;
826   return object_error::success;
827 }
828 
829 error_code MachOObjectFile::getRelocationOffset(DataRefImpl Rel,
830                                                     uint64_t &Res) const {
831   macho::RelocationEntry RE = getRelocation(Rel);
832   Res = getAnyRelocationAddress(RE);
833   return object_error::success;
834 }
835 
836 error_code
837 MachOObjectFile::getRelocationSymbol(DataRefImpl Rel,
838                                          SymbolRef &Res) const {
839   macho::RelocationEntry RE = getRelocation(Rel);
840   uint32_t SymbolIdx = getPlainRelocationSymbolNum(RE);
841   bool isExtern = getPlainRelocationExternal(RE);
842 
843   DataRefImpl Sym;
844   if (isExtern) {
845     Sym.d.b = SymbolIdx;
846   }
847   Res = SymbolRef(Sym, this);
848   return object_error::success;
849 }
850 
851 error_code MachOObjectFile::getRelocationType(DataRefImpl Rel,
852                                                   uint64_t &Res) const {
853   macho::RelocationEntry RE = getRelocation(Rel);
854   Res = getAnyRelocationType(RE);
855   return object_error::success;
856 }
857 
858 error_code
859 MachOObjectFile::getRelocationTypeName(DataRefImpl Rel,
860                                        SmallVectorImpl<char> &Result) const {
861   StringRef res;
862   uint64_t RType;
863   getRelocationType(Rel, RType);
864 
865   unsigned Arch = this->getArch();
866 
867   switch (Arch) {
868     case Triple::x86: {
869       static const char *const Table[] =  {
870         "GENERIC_RELOC_VANILLA",
871         "GENERIC_RELOC_PAIR",
872         "GENERIC_RELOC_SECTDIFF",
873         "GENERIC_RELOC_PB_LA_PTR",
874         "GENERIC_RELOC_LOCAL_SECTDIFF",
875         "GENERIC_RELOC_TLV" };
876 
877       if (RType > 6)
878         res = "Unknown";
879       else
880         res = Table[RType];
881       break;
882     }
883     case Triple::x86_64: {
884       static const char *const Table[] =  {
885         "X86_64_RELOC_UNSIGNED",
886         "X86_64_RELOC_SIGNED",
887         "X86_64_RELOC_BRANCH",
888         "X86_64_RELOC_GOT_LOAD",
889         "X86_64_RELOC_GOT",
890         "X86_64_RELOC_SUBTRACTOR",
891         "X86_64_RELOC_SIGNED_1",
892         "X86_64_RELOC_SIGNED_2",
893         "X86_64_RELOC_SIGNED_4",
894         "X86_64_RELOC_TLV" };
895 
896       if (RType > 9)
897         res = "Unknown";
898       else
899         res = Table[RType];
900       break;
901     }
902     case Triple::arm: {
903       static const char *const Table[] =  {
904         "ARM_RELOC_VANILLA",
905         "ARM_RELOC_PAIR",
906         "ARM_RELOC_SECTDIFF",
907         "ARM_RELOC_LOCAL_SECTDIFF",
908         "ARM_RELOC_PB_LA_PTR",
909         "ARM_RELOC_BR24",
910         "ARM_THUMB_RELOC_BR22",
911         "ARM_THUMB_32BIT_BRANCH",
912         "ARM_RELOC_HALF",
913         "ARM_RELOC_HALF_SECTDIFF" };
914 
915       if (RType > 9)
916         res = "Unknown";
917       else
918         res = Table[RType];
919       break;
920     }
921     case Triple::ppc: {
922       static const char *const Table[] =  {
923         "PPC_RELOC_VANILLA",
924         "PPC_RELOC_PAIR",
925         "PPC_RELOC_BR14",
926         "PPC_RELOC_BR24",
927         "PPC_RELOC_HI16",
928         "PPC_RELOC_LO16",
929         "PPC_RELOC_HA16",
930         "PPC_RELOC_LO14",
931         "PPC_RELOC_SECTDIFF",
932         "PPC_RELOC_PB_LA_PTR",
933         "PPC_RELOC_HI16_SECTDIFF",
934         "PPC_RELOC_LO16_SECTDIFF",
935         "PPC_RELOC_HA16_SECTDIFF",
936         "PPC_RELOC_JBSR",
937         "PPC_RELOC_LO14_SECTDIFF",
938         "PPC_RELOC_LOCAL_SECTDIFF" };
939 
940       res = Table[RType];
941       break;
942     }
943     case Triple::UnknownArch:
944       res = "Unknown";
945       break;
946   }
947   Result.append(res.begin(), res.end());
948   return object_error::success;
949 }
950 
951 error_code MachOObjectFile::getRelocationAdditionalInfo(DataRefImpl Rel,
952                                                         int64_t &Res) const {
953   Res = 0;
954   return object_error::success;
955 }
956 
957 error_code
958 MachOObjectFile::getRelocationValueString(DataRefImpl Rel,
959                                         SmallVectorImpl<char> &Result) const {
960   macho::RelocationEntry RE = getRelocation(Rel);
961 
962   unsigned Arch = this->getArch();
963 
964   std::string fmtbuf;
965   raw_string_ostream fmt(fmtbuf);
966   unsigned Type = this->getAnyRelocationType(RE);
967   bool IsPCRel = this->getAnyRelocationPCRel(RE);
968 
969   // Determine any addends that should be displayed with the relocation.
970   // These require decoding the relocation type, which is triple-specific.
971 
972   // X86_64 has entirely custom relocation types.
973   if (Arch == Triple::x86_64) {
974     bool isPCRel = getAnyRelocationPCRel(RE);
975 
976     switch (Type) {
977       case macho::RIT_X86_64_GOTLoad:   // X86_64_RELOC_GOT_LOAD
978       case macho::RIT_X86_64_GOT: {     // X86_64_RELOC_GOT
979         printRelocationTargetName(this, RE, fmt);
980         fmt << "@GOT";
981         if (isPCRel) fmt << "PCREL";
982         break;
983       }
984       case macho::RIT_X86_64_Subtractor: { // X86_64_RELOC_SUBTRACTOR
985         DataRefImpl RelNext = Rel;
986         RelNext.d.a++;
987         macho::RelocationEntry RENext = getRelocation(RelNext);
988 
989         // X86_64_SUBTRACTOR must be followed by a relocation of type
990         // X86_64_RELOC_UNSIGNED.
991         // NOTE: Scattered relocations don't exist on x86_64.
992         unsigned RType = getAnyRelocationType(RENext);
993         if (RType != 0)
994           report_fatal_error("Expected X86_64_RELOC_UNSIGNED after "
995                              "X86_64_RELOC_SUBTRACTOR.");
996 
997         // The X86_64_RELOC_UNSIGNED contains the minuend symbol,
998         // X86_64_SUBTRACTOR contains to the subtrahend.
999         printRelocationTargetName(this, RENext, fmt);
1000         fmt << "-";
1001         printRelocationTargetName(this, RE, fmt);
1002         break;
1003       }
1004       case macho::RIT_X86_64_TLV:
1005         printRelocationTargetName(this, RE, fmt);
1006         fmt << "@TLV";
1007         if (isPCRel) fmt << "P";
1008         break;
1009       case macho::RIT_X86_64_Signed1: // X86_64_RELOC_SIGNED1
1010         printRelocationTargetName(this, RE, fmt);
1011         fmt << "-1";
1012         break;
1013       case macho::RIT_X86_64_Signed2: // X86_64_RELOC_SIGNED2
1014         printRelocationTargetName(this, RE, fmt);
1015         fmt << "-2";
1016         break;
1017       case macho::RIT_X86_64_Signed4: // X86_64_RELOC_SIGNED4
1018         printRelocationTargetName(this, RE, fmt);
1019         fmt << "-4";
1020         break;
1021       default:
1022         printRelocationTargetName(this, RE, fmt);
1023         break;
1024     }
1025   // X86 and ARM share some relocation types in common.
1026   } else if (Arch == Triple::x86 || Arch == Triple::arm) {
1027     // Generic relocation types...
1028     switch (Type) {
1029       case macho::RIT_Pair: // GENERIC_RELOC_PAIR - prints no info
1030         return object_error::success;
1031       case macho::RIT_Difference: { // GENERIC_RELOC_SECTDIFF
1032         DataRefImpl RelNext = Rel;
1033         RelNext.d.a++;
1034         macho::RelocationEntry RENext = getRelocation(RelNext);
1035 
1036         // X86 sect diff's must be followed by a relocation of type
1037         // GENERIC_RELOC_PAIR.
1038         unsigned RType = getAnyRelocationType(RENext);
1039 
1040         if (RType != 1)
1041           report_fatal_error("Expected GENERIC_RELOC_PAIR after "
1042                              "GENERIC_RELOC_SECTDIFF.");
1043 
1044         printRelocationTargetName(this, RE, fmt);
1045         fmt << "-";
1046         printRelocationTargetName(this, RENext, fmt);
1047         break;
1048       }
1049     }
1050 
1051     if (Arch == Triple::x86) {
1052       // All X86 relocations that need special printing were already
1053       // handled in the generic code.
1054       switch (Type) {
1055         case macho::RIT_Generic_LocalDifference:{// GENERIC_RELOC_LOCAL_SECTDIFF
1056           DataRefImpl RelNext = Rel;
1057           RelNext.d.a++;
1058           macho::RelocationEntry RENext = getRelocation(RelNext);
1059 
1060           // X86 sect diff's must be followed by a relocation of type
1061           // GENERIC_RELOC_PAIR.
1062           unsigned RType = getAnyRelocationType(RENext);
1063           if (RType != 1)
1064             report_fatal_error("Expected GENERIC_RELOC_PAIR after "
1065                                "GENERIC_RELOC_LOCAL_SECTDIFF.");
1066 
1067           printRelocationTargetName(this, RE, fmt);
1068           fmt << "-";
1069           printRelocationTargetName(this, RENext, fmt);
1070           break;
1071         }
1072         case macho::RIT_Generic_TLV: {
1073           printRelocationTargetName(this, RE, fmt);
1074           fmt << "@TLV";
1075           if (IsPCRel) fmt << "P";
1076           break;
1077         }
1078         default:
1079           printRelocationTargetName(this, RE, fmt);
1080       }
1081     } else { // ARM-specific relocations
1082       switch (Type) {
1083         case macho::RIT_ARM_Half:             // ARM_RELOC_HALF
1084         case macho::RIT_ARM_HalfDifference: { // ARM_RELOC_HALF_SECTDIFF
1085           // Half relocations steal a bit from the length field to encode
1086           // whether this is an upper16 or a lower16 relocation.
1087           bool isUpper = getAnyRelocationLength(RE) >> 1;
1088 
1089           if (isUpper)
1090             fmt << ":upper16:(";
1091           else
1092             fmt << ":lower16:(";
1093           printRelocationTargetName(this, RE, fmt);
1094 
1095           DataRefImpl RelNext = Rel;
1096           RelNext.d.a++;
1097           macho::RelocationEntry RENext = getRelocation(RelNext);
1098 
1099           // ARM half relocs must be followed by a relocation of type
1100           // ARM_RELOC_PAIR.
1101           unsigned RType = getAnyRelocationType(RENext);
1102           if (RType != 1)
1103             report_fatal_error("Expected ARM_RELOC_PAIR after "
1104                                "GENERIC_RELOC_HALF");
1105 
1106           // NOTE: The half of the target virtual address is stashed in the
1107           // address field of the secondary relocation, but we can't reverse
1108           // engineer the constant offset from it without decoding the movw/movt
1109           // instruction to find the other half in its immediate field.
1110 
1111           // ARM_RELOC_HALF_SECTDIFF encodes the second section in the
1112           // symbol/section pointer of the follow-on relocation.
1113           if (Type == macho::RIT_ARM_HalfDifference) {
1114             fmt << "-";
1115             printRelocationTargetName(this, RENext, fmt);
1116           }
1117 
1118           fmt << ")";
1119           break;
1120         }
1121         default: {
1122           printRelocationTargetName(this, RE, fmt);
1123         }
1124       }
1125     }
1126   } else
1127     printRelocationTargetName(this, RE, fmt);
1128 
1129   fmt.flush();
1130   Result.append(fmtbuf.begin(), fmtbuf.end());
1131   return object_error::success;
1132 }
1133 
1134 error_code
1135 MachOObjectFile::getRelocationHidden(DataRefImpl Rel,
1136                                      bool &Result) const {
1137   unsigned Arch = getArch();
1138   uint64_t Type;
1139   getRelocationType(Rel, Type);
1140 
1141   Result = false;
1142 
1143   // On arches that use the generic relocations, GENERIC_RELOC_PAIR
1144   // is always hidden.
1145   if (Arch == Triple::x86 || Arch == Triple::arm) {
1146     if (Type == macho::RIT_Pair) Result = true;
1147   } else if (Arch == Triple::x86_64) {
1148     // On x86_64, X86_64_RELOC_UNSIGNED is hidden only when it follows
1149     // an X864_64_RELOC_SUBTRACTOR.
1150     if (Type == macho::RIT_X86_64_Unsigned && Rel.d.a > 0) {
1151       DataRefImpl RelPrev = Rel;
1152       RelPrev.d.a--;
1153       uint64_t PrevType;
1154       getRelocationType(RelPrev, PrevType);
1155       if (PrevType == macho::RIT_X86_64_Subtractor)
1156         Result = true;
1157     }
1158   }
1159 
1160   return object_error::success;
1161 }
1162 
1163 error_code MachOObjectFile::getLibraryNext(DataRefImpl LibData,
1164                                                LibraryRef &Res) const {
1165   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1166 }
1167 
1168 error_code MachOObjectFile::getLibraryPath(DataRefImpl LibData,
1169                                                StringRef &Res) const {
1170   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1171 }
1172 
1173 symbol_iterator MachOObjectFile::begin_symbols() const {
1174   // DRI.d.a = segment number; DRI.d.b = symbol index.
1175   DataRefImpl DRI;
1176   return symbol_iterator(SymbolRef(DRI, this));
1177 }
1178 
1179 symbol_iterator MachOObjectFile::end_symbols() const {
1180   DataRefImpl DRI;
1181   if (SymtabLoadCmd) {
1182     macho::SymtabLoadCommand Symtab = getSymtabLoadCommand();
1183     DRI.d.b = Symtab.NumSymbolTableEntries;
1184   }
1185   return symbol_iterator(SymbolRef(DRI, this));
1186 }
1187 
1188 symbol_iterator MachOObjectFile::begin_dynamic_symbols() const {
1189   // TODO: implement
1190   report_fatal_error("Dynamic symbols unimplemented in MachOObjectFile");
1191 }
1192 
1193 symbol_iterator MachOObjectFile::end_dynamic_symbols() const {
1194   // TODO: implement
1195   report_fatal_error("Dynamic symbols unimplemented in MachOObjectFile");
1196 }
1197 
1198 section_iterator MachOObjectFile::begin_sections() const {
1199   DataRefImpl DRI;
1200   return section_iterator(SectionRef(DRI, this));
1201 }
1202 
1203 section_iterator MachOObjectFile::end_sections() const {
1204   DataRefImpl DRI;
1205   DRI.d.a = Sections.size();
1206   return section_iterator(SectionRef(DRI, this));
1207 }
1208 
1209 library_iterator MachOObjectFile::begin_libraries_needed() const {
1210   // TODO: implement
1211   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1212 }
1213 
1214 library_iterator MachOObjectFile::end_libraries_needed() const {
1215   // TODO: implement
1216   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1217 }
1218 
1219 uint8_t MachOObjectFile::getBytesInAddress() const {
1220   return is64Bit() ? 8 : 4;
1221 }
1222 
1223 StringRef MachOObjectFile::getFileFormatName() const {
1224   unsigned CPUType = getCPUType(this);
1225   if (!is64Bit()) {
1226     switch (CPUType) {
1227     case llvm::MachO::CPUTypeI386:
1228       return "Mach-O 32-bit i386";
1229     case llvm::MachO::CPUTypeARM:
1230       return "Mach-O arm";
1231     case llvm::MachO::CPUTypePowerPC:
1232       return "Mach-O 32-bit ppc";
1233     default:
1234       assert((CPUType & llvm::MachO::CPUArchABI64) == 0 &&
1235              "64-bit object file when we're not 64-bit?");
1236       return "Mach-O 32-bit unknown";
1237     }
1238   }
1239 
1240   // Make sure the cpu type has the correct mask.
1241   assert((CPUType & llvm::MachO::CPUArchABI64)
1242 	 == llvm::MachO::CPUArchABI64 &&
1243 	 "32-bit object file when we're 64-bit?");
1244 
1245   switch (CPUType) {
1246   case llvm::MachO::CPUTypeX86_64:
1247     return "Mach-O 64-bit x86-64";
1248   case llvm::MachO::CPUTypePowerPC64:
1249     return "Mach-O 64-bit ppc64";
1250   default:
1251     return "Mach-O 64-bit unknown";
1252   }
1253 }
1254 
1255 unsigned MachOObjectFile::getArch() const {
1256   switch (getCPUType(this)) {
1257   case llvm::MachO::CPUTypeI386:
1258     return Triple::x86;
1259   case llvm::MachO::CPUTypeX86_64:
1260     return Triple::x86_64;
1261   case llvm::MachO::CPUTypeARM:
1262     return Triple::arm;
1263   case llvm::MachO::CPUTypePowerPC:
1264     return Triple::ppc;
1265   case llvm::MachO::CPUTypePowerPC64:
1266     return Triple::ppc64;
1267   default:
1268     return Triple::UnknownArch;
1269   }
1270 }
1271 
1272 StringRef MachOObjectFile::getLoadName() const {
1273   // TODO: Implement
1274   report_fatal_error("get_load_name() unimplemented in MachOObjectFile");
1275 }
1276 
1277 StringRef
1278 MachOObjectFile::getSectionFinalSegmentName(DataRefImpl Sec) const {
1279   ArrayRef<char> Raw = getSectionRawFinalSegmentName(Sec);
1280   return parseSegmentOrSectionName(Raw.data());
1281 }
1282 
1283 ArrayRef<char>
1284 MachOObjectFile::getSectionRawName(DataRefImpl Sec) const {
1285   const SectionBase *Base =
1286     reinterpret_cast<const SectionBase*>(Sections[Sec.d.a]);
1287   return ArrayRef<char>(Base->Name);
1288 }
1289 
1290 ArrayRef<char>
1291 MachOObjectFile::getSectionRawFinalSegmentName(DataRefImpl Sec) const {
1292   const SectionBase *Base =
1293     reinterpret_cast<const SectionBase*>(Sections[Sec.d.a]);
1294   return ArrayRef<char>(Base->SegmentName);
1295 }
1296 
1297 bool
1298 MachOObjectFile::isRelocationScattered(const macho::RelocationEntry &RE)
1299   const {
1300   if (getCPUType(this) == llvm::MachO::CPUTypeX86_64)
1301     return false;
1302   return getPlainRelocationAddress(RE) & macho::RF_Scattered;
1303 }
1304 
1305 unsigned MachOObjectFile::getPlainRelocationSymbolNum(const macho::RelocationEntry &RE) const {
1306   if (isLittleEndian())
1307     return RE.Word1 & 0xffffff;
1308   return RE.Word1 >> 8;
1309 }
1310 
1311 bool MachOObjectFile::getPlainRelocationExternal(const macho::RelocationEntry &RE) const {
1312   if (isLittleEndian())
1313     return (RE.Word1 >> 27) & 1;
1314   return (RE.Word1 >> 4) & 1;
1315 }
1316 
1317 bool
1318 MachOObjectFile::getScatteredRelocationScattered(const macho::RelocationEntry &RE) const {
1319   return RE.Word0 >> 31;
1320 }
1321 
1322 uint32_t
1323 MachOObjectFile::getScatteredRelocationValue(const macho::RelocationEntry &RE) const {
1324   return RE.Word1;
1325 }
1326 
1327 unsigned
1328 MachOObjectFile::getAnyRelocationAddress(const macho::RelocationEntry &RE) const {
1329   if (isRelocationScattered(RE))
1330     return getScatteredRelocationAddress(RE);
1331   return getPlainRelocationAddress(RE);
1332 }
1333 
1334 unsigned
1335 MachOObjectFile::getAnyRelocationPCRel(const macho::RelocationEntry &RE) const {
1336   if (isRelocationScattered(RE))
1337     return getScatteredRelocationPCRel(this, RE);
1338   return getPlainRelocationPCRel(this, RE);
1339 }
1340 
1341 unsigned
1342 MachOObjectFile::getAnyRelocationLength(const macho::RelocationEntry &RE) const {
1343   if (isRelocationScattered(RE))
1344     return getScatteredRelocationLength(RE);
1345   return getPlainRelocationLength(this, RE);
1346 }
1347 
1348 unsigned
1349 MachOObjectFile::getAnyRelocationType(const macho::RelocationEntry &RE) const {
1350   if (isRelocationScattered(RE))
1351     return getScatteredRelocationType(RE);
1352   return getPlainRelocationType(this, RE);
1353 }
1354 
1355 MachOObjectFile::LoadCommandInfo
1356 MachOObjectFile::getFirstLoadCommandInfo() const {
1357   MachOObjectFile::LoadCommandInfo Load;
1358 
1359   unsigned HeaderSize = is64Bit() ? macho::Header64Size : macho::Header32Size;
1360   Load.Ptr = getPtr(this, HeaderSize);
1361   Load.C = getStruct<macho::LoadCommand>(this, Load.Ptr);
1362   return Load;
1363 }
1364 
1365 MachOObjectFile::LoadCommandInfo
1366 MachOObjectFile::getNextLoadCommandInfo(const LoadCommandInfo &L) const {
1367   MachOObjectFile::LoadCommandInfo Next;
1368   Next.Ptr = L.Ptr + L.C.Size;
1369   Next.C = getStruct<macho::LoadCommand>(this, Next.Ptr);
1370   return Next;
1371 }
1372 
1373 macho::Section MachOObjectFile::getSection(DataRefImpl DRI) const {
1374   return getStruct<macho::Section>(this, Sections[DRI.d.a]);
1375 }
1376 
1377 macho::Section64 MachOObjectFile::getSection64(DataRefImpl DRI) const {
1378   return getStruct<macho::Section64>(this, Sections[DRI.d.a]);
1379 }
1380 
1381 macho::SymbolTableEntry
1382 MachOObjectFile::getSymbolTableEntry(DataRefImpl DRI) const {
1383   const char *P = getSymbolTableEntryPtr(this, DRI);
1384   return getStruct<macho::SymbolTableEntry>(this, P);
1385 }
1386 
1387 macho::Symbol64TableEntry
1388 MachOObjectFile::getSymbol64TableEntry(DataRefImpl DRI) const {
1389   const char *P = getSymbolTableEntryPtr(this, DRI);
1390   return getStruct<macho::Symbol64TableEntry>(this, P);
1391 }
1392 
1393 macho::LinkeditDataLoadCommand
1394 MachOObjectFile::getLinkeditDataLoadCommand(const MachOObjectFile::LoadCommandInfo &L) const {
1395   return getStruct<macho::LinkeditDataLoadCommand>(this, L.Ptr);
1396 }
1397 
1398 macho::RelocationEntry
1399 MachOObjectFile::getRelocation(DataRefImpl Rel) const {
1400   uint32_t RelOffset;
1401   DataRefImpl Sec;
1402   Sec.d.a = Rel.d.b;
1403   if (is64Bit()) {
1404     macho::Section64 Sect = getSection64(Sec);
1405     RelOffset = Sect.RelocationTableOffset;
1406   } else {
1407     macho::Section Sect = getSection(Sec);
1408     RelOffset = Sect.RelocationTableOffset;
1409   }
1410 
1411   uint64_t Offset = RelOffset + Rel.d.a * sizeof(macho::RelocationEntry);
1412   return getStruct<macho::RelocationEntry>(this, getPtr(this, Offset));
1413 }
1414 
1415 macho::Header MachOObjectFile::getHeader() const {
1416   return getStruct<macho::Header>(this, getPtr(this, 0));
1417 }
1418 
1419 macho::SymtabLoadCommand
1420 MachOObjectFile::getSymtabLoadCommand() const {
1421   return getStruct<macho::SymtabLoadCommand>(this, SymtabLoadCmd);
1422 }
1423 
1424 bool MachOObjectFile::is64Bit() const {
1425   return getType() == getMachOType(false, true) ||
1426     getType() == getMachOType(true, true);
1427 }
1428 
1429 void MachOObjectFile::ReadULEB128s(uint64_t Index,
1430                                    SmallVectorImpl<uint64_t> &Out) const {
1431   DataExtractor extractor(ObjectFile::getData(), true, 0);
1432 
1433   uint32_t offset = Index;
1434   uint64_t data = 0;
1435   while (uint64_t delta = extractor.getULEB128(&offset)) {
1436     data += delta;
1437     Out.push_back(data);
1438   }
1439 }
1440 
1441 ObjectFile *ObjectFile::createMachOObjectFile(MemoryBuffer *Buffer) {
1442   StringRef Magic = Buffer->getBuffer().slice(0, 4);
1443   error_code ec;
1444   ObjectFile *Ret;
1445   if (Magic == "\xFE\xED\xFA\xCE")
1446     Ret = new MachOObjectFile(Buffer, false, false, ec);
1447   else if (Magic == "\xCE\xFA\xED\xFE")
1448     Ret = new MachOObjectFile(Buffer, true, false, ec);
1449   else if (Magic == "\xFE\xED\xFA\xCF")
1450     Ret = new MachOObjectFile(Buffer, false, true, ec);
1451   else if (Magic == "\xCF\xFA\xED\xFE")
1452     Ret = new MachOObjectFile(Buffer, true, true, ec);
1453   else
1454     return NULL;
1455 
1456   if (ec)
1457     return NULL;
1458   return Ret;
1459 }
1460 
1461 } // end namespace object
1462 } // end namespace llvm
1463