xref: /llvm-project/llvm/lib/Object/MachOObjectFile.cpp (revision fcbed5af67002c45cf1e02149fa466ef58a5cded) 
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/STLExtras.h"
17 #include "llvm/ADT/Triple.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 "llvm/Support/raw_ostream.h"
23 #include <cctype>
24 #include <cstring>
25 #include <limits>
26 
27 using namespace llvm;
28 using namespace object;
29 
30 namespace llvm {
31 namespace object {
32 
33 struct nlist_base {
34   uint32_t n_strx;
35   uint8_t n_type;
36   uint8_t n_sect;
37   uint16_t n_desc;
38 };
39 
40 struct section_base {
41   char sectname[16];
42   char segname[16];
43 };
44 
45 template<typename T>
46 static void SwapValue(T &Value) {
47   Value = sys::SwapByteOrder(Value);
48 }
49 
50 template<typename T>
51 static void SwapStruct(T &Value);
52 
53 template<>
54 void SwapStruct(MachO::any_relocation_info &H) {
55   SwapValue(H.r_word0);
56   SwapValue(H.r_word1);
57 }
58 
59 template<>
60 void SwapStruct(MachO::load_command &L) {
61   SwapValue(L.cmd);
62   SwapValue(L.cmdsize);
63 }
64 
65 template<>
66 void SwapStruct(nlist_base &S) {
67   SwapValue(S.n_strx);
68   SwapValue(S.n_desc);
69 }
70 
71 template<>
72 void SwapStruct(MachO::section &S) {
73   SwapValue(S.addr);
74   SwapValue(S.size);
75   SwapValue(S.offset);
76   SwapValue(S.align);
77   SwapValue(S.reloff);
78   SwapValue(S.nreloc);
79   SwapValue(S.flags);
80   SwapValue(S.reserved1);
81   SwapValue(S.reserved2);
82 }
83 
84 template<>
85 void SwapStruct(MachO::section_64 &S) {
86   SwapValue(S.addr);
87   SwapValue(S.size);
88   SwapValue(S.offset);
89   SwapValue(S.align);
90   SwapValue(S.reloff);
91   SwapValue(S.nreloc);
92   SwapValue(S.flags);
93   SwapValue(S.reserved1);
94   SwapValue(S.reserved2);
95   SwapValue(S.reserved3);
96 }
97 
98 template<>
99 void SwapStruct(MachO::nlist &S) {
100   SwapValue(S.n_strx);
101   SwapValue(S.n_desc);
102   SwapValue(S.n_value);
103 }
104 
105 template<>
106 void SwapStruct(MachO::nlist_64 &S) {
107   SwapValue(S.n_strx);
108   SwapValue(S.n_desc);
109   SwapValue(S.n_value);
110 }
111 
112 template<>
113 void SwapStruct(MachO::mach_header &H) {
114   SwapValue(H.magic);
115   SwapValue(H.cputype);
116   SwapValue(H.cpusubtype);
117   SwapValue(H.filetype);
118   SwapValue(H.ncmds);
119   SwapValue(H.sizeofcmds);
120   SwapValue(H.flags);
121 }
122 
123 template<>
124 void SwapStruct(MachO::mach_header_64 &H) {
125   SwapValue(H.magic);
126   SwapValue(H.cputype);
127   SwapValue(H.cpusubtype);
128   SwapValue(H.filetype);
129   SwapValue(H.ncmds);
130   SwapValue(H.sizeofcmds);
131   SwapValue(H.flags);
132   SwapValue(H.reserved);
133 }
134 
135 template<>
136 void SwapStruct(MachO::symtab_command &C) {
137   SwapValue(C.cmd);
138   SwapValue(C.cmdsize);
139   SwapValue(C.symoff);
140   SwapValue(C.nsyms);
141   SwapValue(C.stroff);
142   SwapValue(C.strsize);
143 }
144 
145 template<>
146 void SwapStruct(MachO::dysymtab_command &C) {
147   SwapValue(C.cmd);
148   SwapValue(C.cmdsize);
149   SwapValue(C.ilocalsym);
150   SwapValue(C.nlocalsym);
151   SwapValue(C.iextdefsym);
152   SwapValue(C.nextdefsym);
153   SwapValue(C.iundefsym);
154   SwapValue(C.nundefsym);
155   SwapValue(C.tocoff);
156   SwapValue(C.ntoc);
157   SwapValue(C.modtaboff);
158   SwapValue(C.nmodtab);
159   SwapValue(C.extrefsymoff);
160   SwapValue(C.nextrefsyms);
161   SwapValue(C.indirectsymoff);
162   SwapValue(C.nindirectsyms);
163   SwapValue(C.extreloff);
164   SwapValue(C.nextrel);
165   SwapValue(C.locreloff);
166   SwapValue(C.nlocrel);
167 }
168 
169 template<>
170 void SwapStruct(MachO::linkedit_data_command &C) {
171   SwapValue(C.cmd);
172   SwapValue(C.cmdsize);
173   SwapValue(C.dataoff);
174   SwapValue(C.datasize);
175 }
176 
177 template<>
178 void SwapStruct(MachO::segment_command &C) {
179   SwapValue(C.cmd);
180   SwapValue(C.cmdsize);
181   SwapValue(C.vmaddr);
182   SwapValue(C.vmsize);
183   SwapValue(C.fileoff);
184   SwapValue(C.filesize);
185   SwapValue(C.maxprot);
186   SwapValue(C.initprot);
187   SwapValue(C.nsects);
188   SwapValue(C.flags);
189 }
190 
191 template<>
192 void SwapStruct(MachO::segment_command_64 &C) {
193   SwapValue(C.cmd);
194   SwapValue(C.cmdsize);
195   SwapValue(C.vmaddr);
196   SwapValue(C.vmsize);
197   SwapValue(C.fileoff);
198   SwapValue(C.filesize);
199   SwapValue(C.maxprot);
200   SwapValue(C.initprot);
201   SwapValue(C.nsects);
202   SwapValue(C.flags);
203 }
204 
205 template<>
206 void SwapStruct(uint32_t &C) {
207   SwapValue(C);
208 }
209 
210 template<>
211 void SwapStruct(MachO::linker_options_command &C) {
212   SwapValue(C.cmd);
213   SwapValue(C.cmdsize);
214   SwapValue(C.count);
215 }
216 
217 template<>
218 void SwapStruct(MachO::version_min_command&C) {
219   SwapValue(C.cmd);
220   SwapValue(C.cmdsize);
221   SwapValue(C.version);
222   SwapValue(C.reserved);
223 }
224 
225 template<>
226 void SwapStruct(MachO::data_in_code_entry &C) {
227   SwapValue(C.offset);
228   SwapValue(C.length);
229   SwapValue(C.kind);
230 }
231 
232 template<typename T>
233 T getStruct(const MachOObjectFile *O, const char *P) {
234   T Cmd;
235   memcpy(&Cmd, P, sizeof(T));
236   if (O->isLittleEndian() != sys::IsLittleEndianHost)
237     SwapStruct(Cmd);
238   return Cmd;
239 }
240 
241 static uint32_t
242 getSegmentLoadCommandNumSections(const MachOObjectFile *O,
243                                  const MachOObjectFile::LoadCommandInfo &L) {
244   if (O->is64Bit()) {
245     MachO::segment_command_64 S = O->getSegment64LoadCommand(L);
246     return S.nsects;
247   }
248   MachO::segment_command S = O->getSegmentLoadCommand(L);
249   return S.nsects;
250 }
251 
252 static const char *
253 getSectionPtr(const MachOObjectFile *O, MachOObjectFile::LoadCommandInfo L,
254               unsigned Sec) {
255   uintptr_t CommandAddr = reinterpret_cast<uintptr_t>(L.Ptr);
256 
257   bool Is64 = O->is64Bit();
258   unsigned SegmentLoadSize = Is64 ? sizeof(MachO::segment_command_64) :
259                                     sizeof(MachO::segment_command);
260   unsigned SectionSize = Is64 ? sizeof(MachO::section_64) :
261                                 sizeof(MachO::section);
262 
263   uintptr_t SectionAddr = CommandAddr + SegmentLoadSize + Sec * SectionSize;
264   return reinterpret_cast<const char*>(SectionAddr);
265 }
266 
267 static const char *getPtr(const MachOObjectFile *O, size_t Offset) {
268   return O->getData().substr(Offset, 1).data();
269 }
270 
271 static nlist_base
272 getSymbolTableEntryBase(const MachOObjectFile *O, DataRefImpl DRI) {
273   const char *P = reinterpret_cast<const char *>(DRI.p);
274   return getStruct<nlist_base>(O, P);
275 }
276 
277 static StringRef parseSegmentOrSectionName(const char *P) {
278   if (P[15] == 0)
279     // Null terminated.
280     return P;
281   // Not null terminated, so this is a 16 char string.
282   return StringRef(P, 16);
283 }
284 
285 // Helper to advance a section or symbol iterator multiple increments at a time.
286 template<class T>
287 static void advance(T &it, size_t Val) {
288   while (Val--)
289     ++it;
290 }
291 
292 static unsigned getCPUType(const MachOObjectFile *O) {
293   return O->getHeader().cputype;
294 }
295 
296 static void printRelocationTargetName(const MachOObjectFile *O,
297                                       const MachO::any_relocation_info &RE,
298                                       raw_string_ostream &fmt) {
299   bool IsScattered = O->isRelocationScattered(RE);
300 
301   // Target of a scattered relocation is an address.  In the interest of
302   // generating pretty output, scan through the symbol table looking for a
303   // symbol that aligns with that address.  If we find one, print it.
304   // Otherwise, we just print the hex address of the target.
305   if (IsScattered) {
306     uint32_t Val = O->getPlainRelocationSymbolNum(RE);
307 
308     for (const SymbolRef &Symbol : O->symbols()) {
309       error_code ec;
310       uint64_t Addr;
311       StringRef Name;
312 
313       if ((ec = Symbol.getAddress(Addr)))
314         report_fatal_error(ec.message());
315       if (Addr != Val)
316         continue;
317       if ((ec = Symbol.getName(Name)))
318         report_fatal_error(ec.message());
319       fmt << Name;
320       return;
321     }
322 
323     // If we couldn't find a symbol that this relocation refers to, try
324     // to find a section beginning instead.
325     for (const SectionRef &Section : O->sections()) {
326       error_code ec;
327       uint64_t Addr;
328       StringRef Name;
329 
330       if ((ec = Section.getAddress(Addr)))
331         report_fatal_error(ec.message());
332       if (Addr != Val)
333         continue;
334       if ((ec = Section.getName(Name)))
335         report_fatal_error(ec.message());
336       fmt << Name;
337       return;
338     }
339 
340     fmt << format("0x%x", Val);
341     return;
342   }
343 
344   StringRef S;
345   bool isExtern = O->getPlainRelocationExternal(RE);
346   uint64_t Val = O->getPlainRelocationSymbolNum(RE);
347 
348   if (isExtern) {
349     symbol_iterator SI = O->symbol_begin();
350     advance(SI, Val);
351     SI->getName(S);
352   } else {
353     section_iterator SI = O->section_begin();
354     // Adjust for the fact that sections are 1-indexed.
355     advance(SI, Val - 1);
356     SI->getName(S);
357   }
358 
359   fmt << S;
360 }
361 
362 static uint32_t
363 getPlainRelocationAddress(const MachO::any_relocation_info &RE) {
364   return RE.r_word0;
365 }
366 
367 static unsigned
368 getScatteredRelocationAddress(const MachO::any_relocation_info &RE) {
369   return RE.r_word0 & 0xffffff;
370 }
371 
372 static bool getPlainRelocationPCRel(const MachOObjectFile *O,
373                                     const MachO::any_relocation_info &RE) {
374   if (O->isLittleEndian())
375     return (RE.r_word1 >> 24) & 1;
376   return (RE.r_word1 >> 7) & 1;
377 }
378 
379 static bool
380 getScatteredRelocationPCRel(const MachOObjectFile *O,
381                             const MachO::any_relocation_info &RE) {
382   return (RE.r_word0 >> 30) & 1;
383 }
384 
385 static unsigned getPlainRelocationLength(const MachOObjectFile *O,
386                                          const MachO::any_relocation_info &RE) {
387   if (O->isLittleEndian())
388     return (RE.r_word1 >> 25) & 3;
389   return (RE.r_word1 >> 5) & 3;
390 }
391 
392 static unsigned
393 getScatteredRelocationLength(const MachO::any_relocation_info &RE) {
394   return (RE.r_word0 >> 28) & 3;
395 }
396 
397 static unsigned getPlainRelocationType(const MachOObjectFile *O,
398                                        const MachO::any_relocation_info &RE) {
399   if (O->isLittleEndian())
400     return RE.r_word1 >> 28;
401   return RE.r_word1 & 0xf;
402 }
403 
404 static unsigned
405 getScatteredRelocationType(const MachO::any_relocation_info &RE) {
406   return (RE.r_word0 >> 24) & 0xf;
407 }
408 
409 static uint32_t getSectionFlags(const MachOObjectFile *O,
410                                 DataRefImpl Sec) {
411   if (O->is64Bit()) {
412     MachO::section_64 Sect = O->getSection64(Sec);
413     return Sect.flags;
414   }
415   MachO::section Sect = O->getSection(Sec);
416   return Sect.flags;
417 }
418 
419 MachOObjectFile::MachOObjectFile(MemoryBuffer *Object, bool IsLittleEndian,
420                                  bool Is64bits, error_code &EC,
421                                  bool BufferOwned)
422     : ObjectFile(getMachOType(IsLittleEndian, Is64bits), Object, BufferOwned),
423       SymtabLoadCmd(nullptr), DysymtabLoadCmd(nullptr),
424       DataInCodeLoadCmd(nullptr) {
425   uint32_t LoadCommandCount = this->getHeader().ncmds;
426   MachO::LoadCommandType SegmentLoadType = is64Bit() ?
427     MachO::LC_SEGMENT_64 : MachO::LC_SEGMENT;
428 
429   MachOObjectFile::LoadCommandInfo Load = getFirstLoadCommandInfo();
430   for (unsigned I = 0; ; ++I) {
431     if (Load.C.cmd == MachO::LC_SYMTAB) {
432       assert(!SymtabLoadCmd && "Multiple symbol tables");
433       SymtabLoadCmd = Load.Ptr;
434     } else if (Load.C.cmd == MachO::LC_DYSYMTAB) {
435       assert(!DysymtabLoadCmd && "Multiple dynamic symbol tables");
436       DysymtabLoadCmd = Load.Ptr;
437     } else if (Load.C.cmd == MachO::LC_DATA_IN_CODE) {
438       assert(!DataInCodeLoadCmd && "Multiple data in code tables");
439       DataInCodeLoadCmd = Load.Ptr;
440     } else if (Load.C.cmd == SegmentLoadType) {
441       uint32_t NumSections = getSegmentLoadCommandNumSections(this, Load);
442       for (unsigned J = 0; J < NumSections; ++J) {
443         const char *Sec = getSectionPtr(this, Load, J);
444         Sections.push_back(Sec);
445       }
446     }
447 
448     if (I == LoadCommandCount - 1)
449       break;
450     else
451       Load = getNextLoadCommandInfo(Load);
452   }
453 }
454 
455 void MachOObjectFile::moveSymbolNext(DataRefImpl &Symb) const {
456   unsigned SymbolTableEntrySize = is64Bit() ?
457     sizeof(MachO::nlist_64) :
458     sizeof(MachO::nlist);
459   Symb.p += SymbolTableEntrySize;
460 }
461 
462 error_code MachOObjectFile::getSymbolName(DataRefImpl Symb,
463                                           StringRef &Res) const {
464   StringRef StringTable = getStringTableData();
465   nlist_base Entry = getSymbolTableEntryBase(this, Symb);
466   const char *Start = &StringTable.data()[Entry.n_strx];
467   Res = StringRef(Start);
468   return object_error::success;
469 }
470 
471 error_code MachOObjectFile::getSymbolAddress(DataRefImpl Symb,
472                                              uint64_t &Res) const {
473   if (is64Bit()) {
474     MachO::nlist_64 Entry = getSymbol64TableEntry(Symb);
475     Res = Entry.n_value;
476   } else {
477     MachO::nlist Entry = getSymbolTableEntry(Symb);
478     Res = Entry.n_value;
479   }
480   return object_error::success;
481 }
482 
483 error_code MachOObjectFile::getSymbolAlignment(DataRefImpl DRI,
484                                                uint32_t &Result) const {
485   uint32_t flags = getSymbolFlags(DRI);
486   if (flags & SymbolRef::SF_Common) {
487     nlist_base Entry = getSymbolTableEntryBase(this, DRI);
488     Result = 1 << MachO::GET_COMM_ALIGN(Entry.n_desc);
489   } else {
490     Result = 0;
491   }
492   return object_error::success;
493 }
494 
495 error_code MachOObjectFile::getSymbolSize(DataRefImpl DRI,
496                                           uint64_t &Result) const {
497   uint64_t BeginOffset;
498   uint64_t EndOffset = 0;
499   uint8_t SectionIndex;
500 
501   nlist_base Entry = getSymbolTableEntryBase(this, DRI);
502   uint64_t Value;
503   getSymbolAddress(DRI, Value);
504 
505   BeginOffset = Value;
506 
507   SectionIndex = Entry.n_sect;
508   if (!SectionIndex) {
509     uint32_t flags = getSymbolFlags(DRI);
510     if (flags & SymbolRef::SF_Common)
511       Result = Value;
512     else
513       Result = UnknownAddressOrSize;
514     return object_error::success;
515   }
516   // Unfortunately symbols are unsorted so we need to touch all
517   // symbols from load command
518   for (const SymbolRef &Symbol : symbols()) {
519     DataRefImpl DRI = Symbol.getRawDataRefImpl();
520     Entry = getSymbolTableEntryBase(this, DRI);
521     getSymbolAddress(DRI, Value);
522     if (Entry.n_sect == SectionIndex && Value > BeginOffset)
523       if (!EndOffset || Value < EndOffset)
524         EndOffset = Value;
525   }
526   if (!EndOffset) {
527     uint64_t Size;
528     DataRefImpl Sec;
529     Sec.d.a = SectionIndex-1;
530     getSectionSize(Sec, Size);
531     getSectionAddress(Sec, EndOffset);
532     EndOffset += Size;
533   }
534   Result = EndOffset - BeginOffset;
535   return object_error::success;
536 }
537 
538 error_code MachOObjectFile::getSymbolType(DataRefImpl Symb,
539                                           SymbolRef::Type &Res) const {
540   nlist_base Entry = getSymbolTableEntryBase(this, Symb);
541   uint8_t n_type = Entry.n_type;
542 
543   Res = SymbolRef::ST_Other;
544 
545   // If this is a STAB debugging symbol, we can do nothing more.
546   if (n_type & MachO::N_STAB) {
547     Res = SymbolRef::ST_Debug;
548     return object_error::success;
549   }
550 
551   switch (n_type & MachO::N_TYPE) {
552     case MachO::N_UNDF :
553       Res = SymbolRef::ST_Unknown;
554       break;
555     case MachO::N_SECT :
556       Res = SymbolRef::ST_Function;
557       break;
558   }
559   return object_error::success;
560 }
561 
562 uint32_t MachOObjectFile::getSymbolFlags(DataRefImpl DRI) const {
563   nlist_base Entry = getSymbolTableEntryBase(this, DRI);
564 
565   uint8_t MachOType = Entry.n_type;
566   uint16_t MachOFlags = Entry.n_desc;
567 
568   uint32_t Result = SymbolRef::SF_None;
569 
570   if ((MachOType & MachO::N_TYPE) == MachO::N_UNDF)
571     Result |= SymbolRef::SF_Undefined;
572 
573   if (MachOType & MachO::N_STAB)
574     Result |= SymbolRef::SF_FormatSpecific;
575 
576   if (MachOType & MachO::N_EXT) {
577     Result |= SymbolRef::SF_Global;
578     if ((MachOType & MachO::N_TYPE) == MachO::N_UNDF) {
579       uint64_t Value;
580       getSymbolAddress(DRI, Value);
581       if (Value)
582         Result |= SymbolRef::SF_Common;
583     }
584   }
585 
586   if (MachOFlags & (MachO::N_WEAK_REF | MachO::N_WEAK_DEF))
587     Result |= SymbolRef::SF_Weak;
588 
589   if ((MachOType & MachO::N_TYPE) == MachO::N_ABS)
590     Result |= SymbolRef::SF_Absolute;
591 
592   return Result;
593 }
594 
595 error_code
596 MachOObjectFile::getSymbolSection(DataRefImpl Symb,
597                                   section_iterator &Res) const {
598   nlist_base Entry = getSymbolTableEntryBase(this, Symb);
599   uint8_t index = Entry.n_sect;
600 
601   if (index == 0) {
602     Res = section_end();
603   } else {
604     DataRefImpl DRI;
605     DRI.d.a = index - 1;
606     Res = section_iterator(SectionRef(DRI, this));
607   }
608 
609   return object_error::success;
610 }
611 
612 void MachOObjectFile::moveSectionNext(DataRefImpl &Sec) const {
613   Sec.d.a++;
614 }
615 
616 error_code
617 MachOObjectFile::getSectionName(DataRefImpl Sec, StringRef &Result) const {
618   ArrayRef<char> Raw = getSectionRawName(Sec);
619   Result = parseSegmentOrSectionName(Raw.data());
620   return object_error::success;
621 }
622 
623 error_code
624 MachOObjectFile::getSectionAddress(DataRefImpl Sec, uint64_t &Res) const {
625   if (is64Bit()) {
626     MachO::section_64 Sect = getSection64(Sec);
627     Res = Sect.addr;
628   } else {
629     MachO::section Sect = getSection(Sec);
630     Res = Sect.addr;
631   }
632   return object_error::success;
633 }
634 
635 error_code
636 MachOObjectFile::getSectionSize(DataRefImpl Sec, uint64_t &Res) const {
637   if (is64Bit()) {
638     MachO::section_64 Sect = getSection64(Sec);
639     Res = Sect.size;
640   } else {
641     MachO::section Sect = getSection(Sec);
642     Res = Sect.size;
643   }
644 
645   return object_error::success;
646 }
647 
648 error_code
649 MachOObjectFile::getSectionContents(DataRefImpl Sec, StringRef &Res) const {
650   uint32_t Offset;
651   uint64_t Size;
652 
653   if (is64Bit()) {
654     MachO::section_64 Sect = getSection64(Sec);
655     Offset = Sect.offset;
656     Size = Sect.size;
657   } else {
658     MachO::section Sect = getSection(Sec);
659     Offset = Sect.offset;
660     Size = Sect.size;
661   }
662 
663   Res = this->getData().substr(Offset, Size);
664   return object_error::success;
665 }
666 
667 error_code
668 MachOObjectFile::getSectionAlignment(DataRefImpl Sec, uint64_t &Res) const {
669   uint32_t Align;
670   if (is64Bit()) {
671     MachO::section_64 Sect = getSection64(Sec);
672     Align = Sect.align;
673   } else {
674     MachO::section Sect = getSection(Sec);
675     Align = Sect.align;
676   }
677 
678   Res = uint64_t(1) << Align;
679   return object_error::success;
680 }
681 
682 error_code
683 MachOObjectFile::isSectionText(DataRefImpl Sec, bool &Res) const {
684   uint32_t Flags = getSectionFlags(this, Sec);
685   Res = Flags & MachO::S_ATTR_PURE_INSTRUCTIONS;
686   return object_error::success;
687 }
688 
689 error_code MachOObjectFile::isSectionData(DataRefImpl Sec, bool &Result) const {
690   uint32_t Flags = getSectionFlags(this, Sec);
691   unsigned SectionType = Flags & MachO::SECTION_TYPE;
692   Result = !(Flags & MachO::S_ATTR_PURE_INSTRUCTIONS) &&
693            !(SectionType == MachO::S_ZEROFILL ||
694              SectionType == MachO::S_GB_ZEROFILL);
695   return object_error::success;
696 }
697 
698 error_code MachOObjectFile::isSectionBSS(DataRefImpl Sec, bool &Result) const {
699   uint32_t Flags = getSectionFlags(this, Sec);
700   unsigned SectionType = Flags & MachO::SECTION_TYPE;
701   Result = !(Flags & MachO::S_ATTR_PURE_INSTRUCTIONS) &&
702            (SectionType == MachO::S_ZEROFILL ||
703             SectionType == MachO::S_GB_ZEROFILL);
704   return object_error::success;
705 }
706 
707 error_code
708 MachOObjectFile::isSectionRequiredForExecution(DataRefImpl Sec,
709                                                bool &Result) const {
710   // FIXME: Unimplemented.
711   Result = true;
712   return object_error::success;
713 }
714 
715 error_code MachOObjectFile::isSectionVirtual(DataRefImpl Sec,
716                                              bool &Result) const {
717   // FIXME: Unimplemented.
718   Result = false;
719   return object_error::success;
720 }
721 
722 error_code
723 MachOObjectFile::isSectionZeroInit(DataRefImpl Sec, bool &Res) const {
724   uint32_t Flags = getSectionFlags(this, Sec);
725   unsigned SectionType = Flags & MachO::SECTION_TYPE;
726   Res = SectionType == MachO::S_ZEROFILL ||
727     SectionType == MachO::S_GB_ZEROFILL;
728   return object_error::success;
729 }
730 
731 error_code MachOObjectFile::isSectionReadOnlyData(DataRefImpl Sec,
732                                                   bool &Result) const {
733   // Consider using the code from isSectionText to look for __const sections.
734   // Alternately, emit S_ATTR_PURE_INSTRUCTIONS and/or S_ATTR_SOME_INSTRUCTIONS
735   // to use section attributes to distinguish code from data.
736 
737   // FIXME: Unimplemented.
738   Result = false;
739   return object_error::success;
740 }
741 
742 error_code
743 MachOObjectFile::sectionContainsSymbol(DataRefImpl Sec, DataRefImpl Symb,
744                                        bool &Result) const {
745   SymbolRef::Type ST;
746   this->getSymbolType(Symb, ST);
747   if (ST == SymbolRef::ST_Unknown) {
748     Result = false;
749     return object_error::success;
750   }
751 
752   uint64_t SectBegin, SectEnd;
753   getSectionAddress(Sec, SectBegin);
754   getSectionSize(Sec, SectEnd);
755   SectEnd += SectBegin;
756 
757   uint64_t SymAddr;
758   getSymbolAddress(Symb, SymAddr);
759   Result = (SymAddr >= SectBegin) && (SymAddr < SectEnd);
760 
761   return object_error::success;
762 }
763 
764 relocation_iterator MachOObjectFile::section_rel_begin(DataRefImpl Sec) const {
765   DataRefImpl Ret;
766   Ret.d.a = Sec.d.a;
767   Ret.d.b = 0;
768   return relocation_iterator(RelocationRef(Ret, this));
769 }
770 
771 relocation_iterator
772 MachOObjectFile::section_rel_end(DataRefImpl Sec) const {
773   uint32_t Num;
774   if (is64Bit()) {
775     MachO::section_64 Sect = getSection64(Sec);
776     Num = Sect.nreloc;
777   } else {
778     MachO::section Sect = getSection(Sec);
779     Num = Sect.nreloc;
780   }
781 
782   DataRefImpl Ret;
783   Ret.d.a = Sec.d.a;
784   Ret.d.b = Num;
785   return relocation_iterator(RelocationRef(Ret, this));
786 }
787 
788 void MachOObjectFile::moveRelocationNext(DataRefImpl &Rel) const {
789   ++Rel.d.b;
790 }
791 
792 error_code
793 MachOObjectFile::getRelocationAddress(DataRefImpl Rel, uint64_t &Res) const {
794   uint64_t Offset;
795   getRelocationOffset(Rel, Offset);
796 
797   DataRefImpl Sec;
798   Sec.d.a = Rel.d.a;
799   uint64_t SecAddress;
800   getSectionAddress(Sec, SecAddress);
801   Res = SecAddress + Offset;
802   return object_error::success;
803 }
804 
805 error_code MachOObjectFile::getRelocationOffset(DataRefImpl Rel,
806                                                 uint64_t &Res) const {
807   assert(getHeader().filetype == MachO::MH_OBJECT &&
808          "Only implemented for MH_OBJECT");
809   MachO::any_relocation_info RE = getRelocation(Rel);
810   Res = getAnyRelocationAddress(RE);
811   return object_error::success;
812 }
813 
814 symbol_iterator
815 MachOObjectFile::getRelocationSymbol(DataRefImpl Rel) const {
816   MachO::any_relocation_info RE = getRelocation(Rel);
817   uint32_t SymbolIdx = getPlainRelocationSymbolNum(RE);
818   bool isExtern = getPlainRelocationExternal(RE);
819   if (!isExtern)
820     return symbol_end();
821 
822   MachO::symtab_command S = getSymtabLoadCommand();
823   unsigned SymbolTableEntrySize = is64Bit() ?
824     sizeof(MachO::nlist_64) :
825     sizeof(MachO::nlist);
826   uint64_t Offset = S.symoff + SymbolIdx * SymbolTableEntrySize;
827   DataRefImpl Sym;
828   Sym.p = reinterpret_cast<uintptr_t>(getPtr(this, Offset));
829   return symbol_iterator(SymbolRef(Sym, this));
830 }
831 
832 error_code MachOObjectFile::getRelocationType(DataRefImpl Rel,
833                                               uint64_t &Res) const {
834   MachO::any_relocation_info RE = getRelocation(Rel);
835   Res = getAnyRelocationType(RE);
836   return object_error::success;
837 }
838 
839 error_code
840 MachOObjectFile::getRelocationTypeName(DataRefImpl Rel,
841                                        SmallVectorImpl<char> &Result) const {
842   StringRef res;
843   uint64_t RType;
844   getRelocationType(Rel, RType);
845 
846   unsigned Arch = this->getArch();
847 
848   switch (Arch) {
849     case Triple::x86: {
850       static const char *const Table[] =  {
851         "GENERIC_RELOC_VANILLA",
852         "GENERIC_RELOC_PAIR",
853         "GENERIC_RELOC_SECTDIFF",
854         "GENERIC_RELOC_PB_LA_PTR",
855         "GENERIC_RELOC_LOCAL_SECTDIFF",
856         "GENERIC_RELOC_TLV" };
857 
858       if (RType > 5)
859         res = "Unknown";
860       else
861         res = Table[RType];
862       break;
863     }
864     case Triple::x86_64: {
865       static const char *const Table[] =  {
866         "X86_64_RELOC_UNSIGNED",
867         "X86_64_RELOC_SIGNED",
868         "X86_64_RELOC_BRANCH",
869         "X86_64_RELOC_GOT_LOAD",
870         "X86_64_RELOC_GOT",
871         "X86_64_RELOC_SUBTRACTOR",
872         "X86_64_RELOC_SIGNED_1",
873         "X86_64_RELOC_SIGNED_2",
874         "X86_64_RELOC_SIGNED_4",
875         "X86_64_RELOC_TLV" };
876 
877       if (RType > 9)
878         res = "Unknown";
879       else
880         res = Table[RType];
881       break;
882     }
883     case Triple::arm: {
884       static const char *const Table[] =  {
885         "ARM_RELOC_VANILLA",
886         "ARM_RELOC_PAIR",
887         "ARM_RELOC_SECTDIFF",
888         "ARM_RELOC_LOCAL_SECTDIFF",
889         "ARM_RELOC_PB_LA_PTR",
890         "ARM_RELOC_BR24",
891         "ARM_THUMB_RELOC_BR22",
892         "ARM_THUMB_32BIT_BRANCH",
893         "ARM_RELOC_HALF",
894         "ARM_RELOC_HALF_SECTDIFF" };
895 
896       if (RType > 9)
897         res = "Unknown";
898       else
899         res = Table[RType];
900       break;
901     }
902     case Triple::arm64:
903     case Triple::aarch64: {
904       static const char *const Table[] = {
905         "ARM64_RELOC_UNSIGNED",           "ARM64_RELOC_SUBTRACTOR",
906         "ARM64_RELOC_BRANCH26",           "ARM64_RELOC_PAGE21",
907         "ARM64_RELOC_PAGEOFF12",          "ARM64_RELOC_GOT_LOAD_PAGE21",
908         "ARM64_RELOC_GOT_LOAD_PAGEOFF12", "ARM64_RELOC_POINTER_TO_GOT",
909         "ARM64_RELOC_TLVP_LOAD_PAGE21",   "ARM64_RELOC_TLVP_LOAD_PAGEOFF12",
910         "ARM64_RELOC_ADDEND"
911       };
912 
913       if (RType >= array_lengthof(Table))
914         res = "Unknown";
915       else
916         res = Table[RType];
917       break;
918     }
919     case Triple::ppc: {
920       static const char *const Table[] =  {
921         "PPC_RELOC_VANILLA",
922         "PPC_RELOC_PAIR",
923         "PPC_RELOC_BR14",
924         "PPC_RELOC_BR24",
925         "PPC_RELOC_HI16",
926         "PPC_RELOC_LO16",
927         "PPC_RELOC_HA16",
928         "PPC_RELOC_LO14",
929         "PPC_RELOC_SECTDIFF",
930         "PPC_RELOC_PB_LA_PTR",
931         "PPC_RELOC_HI16_SECTDIFF",
932         "PPC_RELOC_LO16_SECTDIFF",
933         "PPC_RELOC_HA16_SECTDIFF",
934         "PPC_RELOC_JBSR",
935         "PPC_RELOC_LO14_SECTDIFF",
936         "PPC_RELOC_LOCAL_SECTDIFF" };
937 
938       if (RType > 15)
939         res = "Unknown";
940       else
941         res = Table[RType];
942       break;
943     }
944     case Triple::UnknownArch:
945       res = "Unknown";
946       break;
947   }
948   Result.append(res.begin(), res.end());
949   return object_error::success;
950 }
951 
952 error_code
953 MachOObjectFile::getRelocationValueString(DataRefImpl Rel,
954                                           SmallVectorImpl<char> &Result) const {
955   MachO::any_relocation_info RE = getRelocation(Rel);
956 
957   unsigned Arch = this->getArch();
958 
959   std::string fmtbuf;
960   raw_string_ostream fmt(fmtbuf);
961   unsigned Type = this->getAnyRelocationType(RE);
962   bool IsPCRel = this->getAnyRelocationPCRel(RE);
963 
964   // Determine any addends that should be displayed with the relocation.
965   // These require decoding the relocation type, which is triple-specific.
966 
967   // X86_64 has entirely custom relocation types.
968   if (Arch == Triple::x86_64) {
969     bool isPCRel = getAnyRelocationPCRel(RE);
970 
971     switch (Type) {
972       case MachO::X86_64_RELOC_GOT_LOAD:
973       case MachO::X86_64_RELOC_GOT: {
974         printRelocationTargetName(this, RE, fmt);
975         fmt << "@GOT";
976         if (isPCRel) fmt << "PCREL";
977         break;
978       }
979       case MachO::X86_64_RELOC_SUBTRACTOR: {
980         DataRefImpl RelNext = Rel;
981         moveRelocationNext(RelNext);
982         MachO::any_relocation_info RENext = getRelocation(RelNext);
983 
984         // X86_64_RELOC_SUBTRACTOR must be followed by a relocation of type
985         // X86_64_RELOC_UNSIGNED.
986         // NOTE: Scattered relocations don't exist on x86_64.
987         unsigned RType = getAnyRelocationType(RENext);
988         if (RType != MachO::X86_64_RELOC_UNSIGNED)
989           report_fatal_error("Expected X86_64_RELOC_UNSIGNED after "
990                              "X86_64_RELOC_SUBTRACTOR.");
991 
992         // The X86_64_RELOC_UNSIGNED contains the minuend symbol;
993         // X86_64_RELOC_SUBTRACTOR contains the subtrahend.
994         printRelocationTargetName(this, RENext, fmt);
995         fmt << "-";
996         printRelocationTargetName(this, RE, fmt);
997         break;
998       }
999       case MachO::X86_64_RELOC_TLV:
1000         printRelocationTargetName(this, RE, fmt);
1001         fmt << "@TLV";
1002         if (isPCRel) fmt << "P";
1003         break;
1004       case MachO::X86_64_RELOC_SIGNED_1:
1005         printRelocationTargetName(this, RE, fmt);
1006         fmt << "-1";
1007         break;
1008       case MachO::X86_64_RELOC_SIGNED_2:
1009         printRelocationTargetName(this, RE, fmt);
1010         fmt << "-2";
1011         break;
1012       case MachO::X86_64_RELOC_SIGNED_4:
1013         printRelocationTargetName(this, RE, fmt);
1014         fmt << "-4";
1015         break;
1016       default:
1017         printRelocationTargetName(this, RE, fmt);
1018         break;
1019     }
1020   // X86 and ARM share some relocation types in common.
1021   } else if (Arch == Triple::x86 || Arch == Triple::arm ||
1022              Arch == Triple::ppc) {
1023     // Generic relocation types...
1024     switch (Type) {
1025       case MachO::GENERIC_RELOC_PAIR: // prints no info
1026         return object_error::success;
1027       case MachO::GENERIC_RELOC_SECTDIFF: {
1028         DataRefImpl RelNext = Rel;
1029         moveRelocationNext(RelNext);
1030         MachO::any_relocation_info RENext = getRelocation(RelNext);
1031 
1032         // X86 sect diff's must be followed by a relocation of type
1033         // GENERIC_RELOC_PAIR.
1034         unsigned RType = getAnyRelocationType(RENext);
1035 
1036         if (RType != MachO::GENERIC_RELOC_PAIR)
1037           report_fatal_error("Expected GENERIC_RELOC_PAIR after "
1038                              "GENERIC_RELOC_SECTDIFF.");
1039 
1040         printRelocationTargetName(this, RE, fmt);
1041         fmt << "-";
1042         printRelocationTargetName(this, RENext, fmt);
1043         break;
1044       }
1045     }
1046 
1047     if (Arch == Triple::x86 || Arch == Triple::ppc) {
1048       switch (Type) {
1049         case MachO::GENERIC_RELOC_LOCAL_SECTDIFF: {
1050           DataRefImpl RelNext = Rel;
1051           moveRelocationNext(RelNext);
1052           MachO::any_relocation_info RENext = getRelocation(RelNext);
1053 
1054           // X86 sect diff's must be followed by a relocation of type
1055           // GENERIC_RELOC_PAIR.
1056           unsigned RType = getAnyRelocationType(RENext);
1057           if (RType != MachO::GENERIC_RELOC_PAIR)
1058             report_fatal_error("Expected GENERIC_RELOC_PAIR after "
1059                                "GENERIC_RELOC_LOCAL_SECTDIFF.");
1060 
1061           printRelocationTargetName(this, RE, fmt);
1062           fmt << "-";
1063           printRelocationTargetName(this, RENext, fmt);
1064           break;
1065         }
1066         case MachO::GENERIC_RELOC_TLV: {
1067           printRelocationTargetName(this, RE, fmt);
1068           fmt << "@TLV";
1069           if (IsPCRel) fmt << "P";
1070           break;
1071         }
1072         default:
1073           printRelocationTargetName(this, RE, fmt);
1074       }
1075     } else { // ARM-specific relocations
1076       switch (Type) {
1077         case MachO::ARM_RELOC_HALF:
1078         case MachO::ARM_RELOC_HALF_SECTDIFF: {
1079           // Half relocations steal a bit from the length field to encode
1080           // whether this is an upper16 or a lower16 relocation.
1081           bool isUpper = getAnyRelocationLength(RE) >> 1;
1082 
1083           if (isUpper)
1084             fmt << ":upper16:(";
1085           else
1086             fmt << ":lower16:(";
1087           printRelocationTargetName(this, RE, fmt);
1088 
1089           DataRefImpl RelNext = Rel;
1090           moveRelocationNext(RelNext);
1091           MachO::any_relocation_info RENext = getRelocation(RelNext);
1092 
1093           // ARM half relocs must be followed by a relocation of type
1094           // ARM_RELOC_PAIR.
1095           unsigned RType = getAnyRelocationType(RENext);
1096           if (RType != MachO::ARM_RELOC_PAIR)
1097             report_fatal_error("Expected ARM_RELOC_PAIR after "
1098                                "ARM_RELOC_HALF");
1099 
1100           // NOTE: The half of the target virtual address is stashed in the
1101           // address field of the secondary relocation, but we can't reverse
1102           // engineer the constant offset from it without decoding the movw/movt
1103           // instruction to find the other half in its immediate field.
1104 
1105           // ARM_RELOC_HALF_SECTDIFF encodes the second section in the
1106           // symbol/section pointer of the follow-on relocation.
1107           if (Type == MachO::ARM_RELOC_HALF_SECTDIFF) {
1108             fmt << "-";
1109             printRelocationTargetName(this, RENext, fmt);
1110           }
1111 
1112           fmt << ")";
1113           break;
1114         }
1115         default: {
1116           printRelocationTargetName(this, RE, fmt);
1117         }
1118       }
1119     }
1120   } else
1121     printRelocationTargetName(this, RE, fmt);
1122 
1123   fmt.flush();
1124   Result.append(fmtbuf.begin(), fmtbuf.end());
1125   return object_error::success;
1126 }
1127 
1128 error_code
1129 MachOObjectFile::getRelocationHidden(DataRefImpl Rel, bool &Result) const {
1130   unsigned Arch = getArch();
1131   uint64_t Type;
1132   getRelocationType(Rel, Type);
1133 
1134   Result = false;
1135 
1136   // On arches that use the generic relocations, GENERIC_RELOC_PAIR
1137   // is always hidden.
1138   if (Arch == Triple::x86 || Arch == Triple::arm || Arch == Triple::ppc) {
1139     if (Type == MachO::GENERIC_RELOC_PAIR) Result = true;
1140   } else if (Arch == Triple::x86_64) {
1141     // On x86_64, X86_64_RELOC_UNSIGNED is hidden only when it follows
1142     // an X86_64_RELOC_SUBTRACTOR.
1143     if (Type == MachO::X86_64_RELOC_UNSIGNED && Rel.d.a > 0) {
1144       DataRefImpl RelPrev = Rel;
1145       RelPrev.d.a--;
1146       uint64_t PrevType;
1147       getRelocationType(RelPrev, PrevType);
1148       if (PrevType == MachO::X86_64_RELOC_SUBTRACTOR)
1149         Result = true;
1150     }
1151   }
1152 
1153   return object_error::success;
1154 }
1155 
1156 error_code MachOObjectFile::getLibraryNext(DataRefImpl LibData,
1157                                            LibraryRef &Res) const {
1158   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1159 }
1160 
1161 error_code MachOObjectFile::getLibraryPath(DataRefImpl LibData,
1162                                            StringRef &Res) const {
1163   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1164 }
1165 
1166 basic_symbol_iterator MachOObjectFile::symbol_begin_impl() const {
1167   return getSymbolByIndex(0);
1168 }
1169 
1170 basic_symbol_iterator MachOObjectFile::symbol_end_impl() const {
1171   DataRefImpl DRI;
1172   if (!SymtabLoadCmd)
1173     return basic_symbol_iterator(SymbolRef(DRI, this));
1174 
1175   MachO::symtab_command Symtab = getSymtabLoadCommand();
1176   unsigned SymbolTableEntrySize = is64Bit() ?
1177     sizeof(MachO::nlist_64) :
1178     sizeof(MachO::nlist);
1179   unsigned Offset = Symtab.symoff +
1180     Symtab.nsyms * SymbolTableEntrySize;
1181   DRI.p = reinterpret_cast<uintptr_t>(getPtr(this, Offset));
1182   return basic_symbol_iterator(SymbolRef(DRI, this));
1183 }
1184 
1185 basic_symbol_iterator MachOObjectFile::getSymbolByIndex(unsigned Index) const {
1186   DataRefImpl DRI;
1187   if (!SymtabLoadCmd)
1188     return basic_symbol_iterator(SymbolRef(DRI, this));
1189 
1190   MachO::symtab_command Symtab = getSymtabLoadCommand();
1191   assert(Index < Symtab.nsyms && "Requested symbol index is out of range.");
1192   unsigned SymbolTableEntrySize =
1193     is64Bit() ? sizeof(MachO::nlist_64) : sizeof(MachO::nlist);
1194   DRI.p = reinterpret_cast<uintptr_t>(getPtr(this, Symtab.symoff));
1195   DRI.p += Index * SymbolTableEntrySize;
1196   return basic_symbol_iterator(SymbolRef(DRI, this));
1197 }
1198 
1199 section_iterator MachOObjectFile::section_begin() const {
1200   DataRefImpl DRI;
1201   return section_iterator(SectionRef(DRI, this));
1202 }
1203 
1204 section_iterator MachOObjectFile::section_end() const {
1205   DataRefImpl DRI;
1206   DRI.d.a = Sections.size();
1207   return section_iterator(SectionRef(DRI, this));
1208 }
1209 
1210 library_iterator MachOObjectFile::needed_library_begin() const {
1211   // TODO: implement
1212   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1213 }
1214 
1215 library_iterator MachOObjectFile::needed_library_end() const {
1216   // TODO: implement
1217   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1218 }
1219 
1220 uint8_t MachOObjectFile::getBytesInAddress() const {
1221   return is64Bit() ? 8 : 4;
1222 }
1223 
1224 StringRef MachOObjectFile::getFileFormatName() const {
1225   unsigned CPUType = getCPUType(this);
1226   if (!is64Bit()) {
1227     switch (CPUType) {
1228     case llvm::MachO::CPU_TYPE_I386:
1229       return "Mach-O 32-bit i386";
1230     case llvm::MachO::CPU_TYPE_ARM:
1231       return "Mach-O arm";
1232     case llvm::MachO::CPU_TYPE_POWERPC:
1233       return "Mach-O 32-bit ppc";
1234     default:
1235       assert((CPUType & llvm::MachO::CPU_ARCH_ABI64) == 0 &&
1236              "64-bit object file when we're not 64-bit?");
1237       return "Mach-O 32-bit unknown";
1238     }
1239   }
1240 
1241   // Make sure the cpu type has the correct mask.
1242   assert((CPUType & llvm::MachO::CPU_ARCH_ABI64)
1243          == llvm::MachO::CPU_ARCH_ABI64 &&
1244          "32-bit object file when we're 64-bit?");
1245 
1246   switch (CPUType) {
1247   case llvm::MachO::CPU_TYPE_X86_64:
1248     return "Mach-O 64-bit x86-64";
1249   case llvm::MachO::CPU_TYPE_ARM64:
1250     return "Mach-O arm64";
1251   case llvm::MachO::CPU_TYPE_POWERPC64:
1252     return "Mach-O 64-bit ppc64";
1253   default:
1254     return "Mach-O 64-bit unknown";
1255   }
1256 }
1257 
1258 Triple::ArchType MachOObjectFile::getArch(uint32_t CPUType) {
1259   switch (CPUType) {
1260   case llvm::MachO::CPU_TYPE_I386:
1261     return Triple::x86;
1262   case llvm::MachO::CPU_TYPE_X86_64:
1263     return Triple::x86_64;
1264   case llvm::MachO::CPU_TYPE_ARM:
1265     return Triple::arm;
1266   case llvm::MachO::CPU_TYPE_ARM64:
1267     return Triple::arm64;
1268   case llvm::MachO::CPU_TYPE_POWERPC:
1269     return Triple::ppc;
1270   case llvm::MachO::CPU_TYPE_POWERPC64:
1271     return Triple::ppc64;
1272   default:
1273     return Triple::UnknownArch;
1274   }
1275 }
1276 
1277 unsigned MachOObjectFile::getArch() const {
1278   return getArch(getCPUType(this));
1279 }
1280 
1281 StringRef MachOObjectFile::getLoadName() const {
1282   // TODO: Implement
1283   report_fatal_error("get_load_name() unimplemented in MachOObjectFile");
1284 }
1285 
1286 relocation_iterator MachOObjectFile::section_rel_begin(unsigned Index) const {
1287   DataRefImpl DRI;
1288   DRI.d.a = Index;
1289   return section_rel_begin(DRI);
1290 }
1291 
1292 relocation_iterator MachOObjectFile::section_rel_end(unsigned Index) const {
1293   DataRefImpl DRI;
1294   DRI.d.a = Index;
1295   return section_rel_end(DRI);
1296 }
1297 
1298 dice_iterator MachOObjectFile::begin_dices() const {
1299   DataRefImpl DRI;
1300   if (!DataInCodeLoadCmd)
1301     return dice_iterator(DiceRef(DRI, this));
1302 
1303   MachO::linkedit_data_command DicLC = getDataInCodeLoadCommand();
1304   DRI.p = reinterpret_cast<uintptr_t>(getPtr(this, DicLC.dataoff));
1305   return dice_iterator(DiceRef(DRI, this));
1306 }
1307 
1308 dice_iterator MachOObjectFile::end_dices() const {
1309   DataRefImpl DRI;
1310   if (!DataInCodeLoadCmd)
1311     return dice_iterator(DiceRef(DRI, this));
1312 
1313   MachO::linkedit_data_command DicLC = getDataInCodeLoadCommand();
1314   unsigned Offset = DicLC.dataoff + DicLC.datasize;
1315   DRI.p = reinterpret_cast<uintptr_t>(getPtr(this, Offset));
1316   return dice_iterator(DiceRef(DRI, this));
1317 }
1318 
1319 StringRef
1320 MachOObjectFile::getSectionFinalSegmentName(DataRefImpl Sec) const {
1321   ArrayRef<char> Raw = getSectionRawFinalSegmentName(Sec);
1322   return parseSegmentOrSectionName(Raw.data());
1323 }
1324 
1325 ArrayRef<char>
1326 MachOObjectFile::getSectionRawName(DataRefImpl Sec) const {
1327   const section_base *Base =
1328     reinterpret_cast<const section_base *>(Sections[Sec.d.a]);
1329   return ArrayRef<char>(Base->sectname);
1330 }
1331 
1332 ArrayRef<char>
1333 MachOObjectFile::getSectionRawFinalSegmentName(DataRefImpl Sec) const {
1334   const section_base *Base =
1335     reinterpret_cast<const section_base *>(Sections[Sec.d.a]);
1336   return ArrayRef<char>(Base->segname);
1337 }
1338 
1339 bool
1340 MachOObjectFile::isRelocationScattered(const MachO::any_relocation_info &RE)
1341   const {
1342   if (getCPUType(this) == MachO::CPU_TYPE_X86_64)
1343     return false;
1344   return getPlainRelocationAddress(RE) & MachO::R_SCATTERED;
1345 }
1346 
1347 unsigned MachOObjectFile::getPlainRelocationSymbolNum(
1348     const MachO::any_relocation_info &RE) const {
1349   if (isLittleEndian())
1350     return RE.r_word1 & 0xffffff;
1351   return RE.r_word1 >> 8;
1352 }
1353 
1354 bool MachOObjectFile::getPlainRelocationExternal(
1355     const MachO::any_relocation_info &RE) const {
1356   if (isLittleEndian())
1357     return (RE.r_word1 >> 27) & 1;
1358   return (RE.r_word1 >> 4) & 1;
1359 }
1360 
1361 bool MachOObjectFile::getScatteredRelocationScattered(
1362     const MachO::any_relocation_info &RE) const {
1363   return RE.r_word0 >> 31;
1364 }
1365 
1366 uint32_t MachOObjectFile::getScatteredRelocationValue(
1367     const MachO::any_relocation_info &RE) const {
1368   return RE.r_word1;
1369 }
1370 
1371 unsigned MachOObjectFile::getAnyRelocationAddress(
1372     const MachO::any_relocation_info &RE) const {
1373   if (isRelocationScattered(RE))
1374     return getScatteredRelocationAddress(RE);
1375   return getPlainRelocationAddress(RE);
1376 }
1377 
1378 unsigned MachOObjectFile::getAnyRelocationPCRel(
1379     const MachO::any_relocation_info &RE) const {
1380   if (isRelocationScattered(RE))
1381     return getScatteredRelocationPCRel(this, RE);
1382   return getPlainRelocationPCRel(this, RE);
1383 }
1384 
1385 unsigned MachOObjectFile::getAnyRelocationLength(
1386     const MachO::any_relocation_info &RE) const {
1387   if (isRelocationScattered(RE))
1388     return getScatteredRelocationLength(RE);
1389   return getPlainRelocationLength(this, RE);
1390 }
1391 
1392 unsigned
1393 MachOObjectFile::getAnyRelocationType(
1394                                    const MachO::any_relocation_info &RE) const {
1395   if (isRelocationScattered(RE))
1396     return getScatteredRelocationType(RE);
1397   return getPlainRelocationType(this, RE);
1398 }
1399 
1400 SectionRef
1401 MachOObjectFile::getRelocationSection(
1402                                    const MachO::any_relocation_info &RE) const {
1403   if (isRelocationScattered(RE) || getPlainRelocationExternal(RE))
1404     return *section_end();
1405   unsigned SecNum = getPlainRelocationSymbolNum(RE) - 1;
1406   DataRefImpl DRI;
1407   DRI.d.a = SecNum;
1408   return SectionRef(DRI, this);
1409 }
1410 
1411 MachOObjectFile::LoadCommandInfo
1412 MachOObjectFile::getFirstLoadCommandInfo() const {
1413   MachOObjectFile::LoadCommandInfo Load;
1414 
1415   unsigned HeaderSize = is64Bit() ? sizeof(MachO::mach_header_64) :
1416                                     sizeof(MachO::mach_header);
1417   Load.Ptr = getPtr(this, HeaderSize);
1418   Load.C = getStruct<MachO::load_command>(this, Load.Ptr);
1419   return Load;
1420 }
1421 
1422 MachOObjectFile::LoadCommandInfo
1423 MachOObjectFile::getNextLoadCommandInfo(const LoadCommandInfo &L) const {
1424   MachOObjectFile::LoadCommandInfo Next;
1425   Next.Ptr = L.Ptr + L.C.cmdsize;
1426   Next.C = getStruct<MachO::load_command>(this, Next.Ptr);
1427   return Next;
1428 }
1429 
1430 MachO::section MachOObjectFile::getSection(DataRefImpl DRI) const {
1431   return getStruct<MachO::section>(this, Sections[DRI.d.a]);
1432 }
1433 
1434 MachO::section_64 MachOObjectFile::getSection64(DataRefImpl DRI) const {
1435   return getStruct<MachO::section_64>(this, Sections[DRI.d.a]);
1436 }
1437 
1438 MachO::section MachOObjectFile::getSection(const LoadCommandInfo &L,
1439                                            unsigned Index) const {
1440   const char *Sec = getSectionPtr(this, L, Index);
1441   return getStruct<MachO::section>(this, Sec);
1442 }
1443 
1444 MachO::section_64 MachOObjectFile::getSection64(const LoadCommandInfo &L,
1445                                                 unsigned Index) const {
1446   const char *Sec = getSectionPtr(this, L, Index);
1447   return getStruct<MachO::section_64>(this, Sec);
1448 }
1449 
1450 MachO::nlist
1451 MachOObjectFile::getSymbolTableEntry(DataRefImpl DRI) const {
1452   const char *P = reinterpret_cast<const char *>(DRI.p);
1453   return getStruct<MachO::nlist>(this, P);
1454 }
1455 
1456 MachO::nlist_64
1457 MachOObjectFile::getSymbol64TableEntry(DataRefImpl DRI) const {
1458   const char *P = reinterpret_cast<const char *>(DRI.p);
1459   return getStruct<MachO::nlist_64>(this, P);
1460 }
1461 
1462 MachO::linkedit_data_command
1463 MachOObjectFile::getLinkeditDataLoadCommand(const LoadCommandInfo &L) const {
1464   return getStruct<MachO::linkedit_data_command>(this, L.Ptr);
1465 }
1466 
1467 MachO::segment_command
1468 MachOObjectFile::getSegmentLoadCommand(const LoadCommandInfo &L) const {
1469   return getStruct<MachO::segment_command>(this, L.Ptr);
1470 }
1471 
1472 MachO::segment_command_64
1473 MachOObjectFile::getSegment64LoadCommand(const LoadCommandInfo &L) const {
1474   return getStruct<MachO::segment_command_64>(this, L.Ptr);
1475 }
1476 
1477 MachO::linker_options_command
1478 MachOObjectFile::getLinkerOptionsLoadCommand(const LoadCommandInfo &L) const {
1479   return getStruct<MachO::linker_options_command>(this, L.Ptr);
1480 }
1481 
1482 MachO::version_min_command
1483 MachOObjectFile::getVersionMinLoadCommand(const LoadCommandInfo &L) const {
1484   return getStruct<MachO::version_min_command>(this, L.Ptr);
1485 }
1486 
1487 MachO::any_relocation_info
1488 MachOObjectFile::getRelocation(DataRefImpl Rel) const {
1489   DataRefImpl Sec;
1490   Sec.d.a = Rel.d.a;
1491   uint32_t Offset;
1492   if (is64Bit()) {
1493     MachO::section_64 Sect = getSection64(Sec);
1494     Offset = Sect.reloff;
1495   } else {
1496     MachO::section Sect = getSection(Sec);
1497     Offset = Sect.reloff;
1498   }
1499 
1500   auto P = reinterpret_cast<const MachO::any_relocation_info *>(
1501       getPtr(this, Offset)) + Rel.d.b;
1502   return getStruct<MachO::any_relocation_info>(
1503       this, reinterpret_cast<const char *>(P));
1504 }
1505 
1506 MachO::data_in_code_entry
1507 MachOObjectFile::getDice(DataRefImpl Rel) const {
1508   const char *P = reinterpret_cast<const char *>(Rel.p);
1509   return getStruct<MachO::data_in_code_entry>(this, P);
1510 }
1511 
1512 MachO::mach_header MachOObjectFile::getHeader() const {
1513   return getStruct<MachO::mach_header>(this, getPtr(this, 0));
1514 }
1515 
1516 MachO::mach_header_64 MachOObjectFile::getHeader64() const {
1517   return getStruct<MachO::mach_header_64>(this, getPtr(this, 0));
1518 }
1519 
1520 uint32_t MachOObjectFile::getIndirectSymbolTableEntry(
1521                                              const MachO::dysymtab_command &DLC,
1522                                              unsigned Index) const {
1523   uint64_t Offset = DLC.indirectsymoff + Index * sizeof(uint32_t);
1524   return getStruct<uint32_t>(this, getPtr(this, Offset));
1525 }
1526 
1527 MachO::data_in_code_entry
1528 MachOObjectFile::getDataInCodeTableEntry(uint32_t DataOffset,
1529                                          unsigned Index) const {
1530   uint64_t Offset = DataOffset + Index * sizeof(MachO::data_in_code_entry);
1531   return getStruct<MachO::data_in_code_entry>(this, getPtr(this, Offset));
1532 }
1533 
1534 MachO::symtab_command MachOObjectFile::getSymtabLoadCommand() const {
1535   return getStruct<MachO::symtab_command>(this, SymtabLoadCmd);
1536 }
1537 
1538 MachO::dysymtab_command MachOObjectFile::getDysymtabLoadCommand() const {
1539   return getStruct<MachO::dysymtab_command>(this, DysymtabLoadCmd);
1540 }
1541 
1542 MachO::linkedit_data_command
1543 MachOObjectFile::getDataInCodeLoadCommand() const {
1544   if (DataInCodeLoadCmd)
1545     return getStruct<MachO::linkedit_data_command>(this, DataInCodeLoadCmd);
1546 
1547   // If there is no DataInCodeLoadCmd return a load command with zero'ed fields.
1548   MachO::linkedit_data_command Cmd;
1549   Cmd.cmd = MachO::LC_DATA_IN_CODE;
1550   Cmd.cmdsize = sizeof(MachO::linkedit_data_command);
1551   Cmd.dataoff = 0;
1552   Cmd.datasize = 0;
1553   return Cmd;
1554 }
1555 
1556 StringRef MachOObjectFile::getStringTableData() const {
1557   MachO::symtab_command S = getSymtabLoadCommand();
1558   return getData().substr(S.stroff, S.strsize);
1559 }
1560 
1561 bool MachOObjectFile::is64Bit() const {
1562   return getType() == getMachOType(false, true) ||
1563     getType() == getMachOType(true, true);
1564 }
1565 
1566 void MachOObjectFile::ReadULEB128s(uint64_t Index,
1567                                    SmallVectorImpl<uint64_t> &Out) const {
1568   DataExtractor extractor(ObjectFile::getData(), true, 0);
1569 
1570   uint32_t offset = Index;
1571   uint64_t data = 0;
1572   while (uint64_t delta = extractor.getULEB128(&offset)) {
1573     data += delta;
1574     Out.push_back(data);
1575   }
1576 }
1577 
1578 ErrorOr<ObjectFile *> ObjectFile::createMachOObjectFile(MemoryBuffer *Buffer,
1579                                                         bool BufferOwned) {
1580   StringRef Magic = Buffer->getBuffer().slice(0, 4);
1581   error_code EC;
1582   std::unique_ptr<MachOObjectFile> Ret;
1583   if (Magic == "\xFE\xED\xFA\xCE")
1584     Ret.reset(new MachOObjectFile(Buffer, false, false, EC, BufferOwned));
1585   else if (Magic == "\xCE\xFA\xED\xFE")
1586     Ret.reset(new MachOObjectFile(Buffer, true, false, EC, BufferOwned));
1587   else if (Magic == "\xFE\xED\xFA\xCF")
1588     Ret.reset(new MachOObjectFile(Buffer, false, true, EC, BufferOwned));
1589   else if (Magic == "\xCF\xFA\xED\xFE")
1590     Ret.reset(new MachOObjectFile(Buffer, true, true, EC, BufferOwned));
1591   else {
1592     delete Buffer;
1593     return object_error::parse_failed;
1594   }
1595 
1596   if (EC)
1597     return EC;
1598   return Ret.release();
1599 }
1600 
1601 } // end namespace object
1602 } // end namespace llvm
1603