xref: /llvm-project/llvm/lib/Object/MachOObjectFile.cpp (revision 7247546ba3b17565ff59f76d31b69ac948459e32) 
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(NULL), DysymtabLoadCmd(NULL), DataInCodeLoadCmd(NULL) {
424   uint32_t LoadCommandCount = this->getHeader().ncmds;
425   MachO::LoadCommandType SegmentLoadType = is64Bit() ?
426     MachO::LC_SEGMENT_64 : MachO::LC_SEGMENT;
427 
428   MachOObjectFile::LoadCommandInfo Load = getFirstLoadCommandInfo();
429   for (unsigned I = 0; ; ++I) {
430     if (Load.C.cmd == MachO::LC_SYMTAB) {
431       assert(!SymtabLoadCmd && "Multiple symbol tables");
432       SymtabLoadCmd = Load.Ptr;
433     } else if (Load.C.cmd == MachO::LC_DYSYMTAB) {
434       assert(!DysymtabLoadCmd && "Multiple dynamic symbol tables");
435       DysymtabLoadCmd = Load.Ptr;
436     } else if (Load.C.cmd == MachO::LC_DATA_IN_CODE) {
437       assert(!DataInCodeLoadCmd && "Multiple data in code tables");
438       DataInCodeLoadCmd = Load.Ptr;
439     } else if (Load.C.cmd == SegmentLoadType) {
440       uint32_t NumSections = getSegmentLoadCommandNumSections(this, Load);
441       for (unsigned J = 0; J < NumSections; ++J) {
442         const char *Sec = getSectionPtr(this, Load, J);
443         Sections.push_back(Sec);
444       }
445     }
446 
447     if (I == LoadCommandCount - 1)
448       break;
449     else
450       Load = getNextLoadCommandInfo(Load);
451   }
452 }
453 
454 void MachOObjectFile::moveSymbolNext(DataRefImpl &Symb) const {
455   unsigned SymbolTableEntrySize = is64Bit() ?
456     sizeof(MachO::nlist_64) :
457     sizeof(MachO::nlist);
458   Symb.p += SymbolTableEntrySize;
459 }
460 
461 error_code MachOObjectFile::getSymbolName(DataRefImpl Symb,
462                                           StringRef &Res) const {
463   StringRef StringTable = getStringTableData();
464   nlist_base Entry = getSymbolTableEntryBase(this, Symb);
465   const char *Start = &StringTable.data()[Entry.n_strx];
466   Res = StringRef(Start);
467   return object_error::success;
468 }
469 
470 error_code MachOObjectFile::getSymbolAddress(DataRefImpl Symb,
471                                              uint64_t &Res) const {
472   if (is64Bit()) {
473     MachO::nlist_64 Entry = getSymbol64TableEntry(Symb);
474     Res = Entry.n_value;
475   } else {
476     MachO::nlist Entry = getSymbolTableEntry(Symb);
477     Res = Entry.n_value;
478   }
479   return object_error::success;
480 }
481 
482 error_code MachOObjectFile::getSymbolAlignment(DataRefImpl DRI,
483                                                uint32_t &Result) const {
484   uint32_t flags = getSymbolFlags(DRI);
485   if (flags & SymbolRef::SF_Common) {
486     nlist_base Entry = getSymbolTableEntryBase(this, DRI);
487     Result = 1 << MachO::GET_COMM_ALIGN(Entry.n_desc);
488   } else {
489     Result = 0;
490   }
491   return object_error::success;
492 }
493 
494 error_code MachOObjectFile::getSymbolSize(DataRefImpl DRI,
495                                           uint64_t &Result) const {
496   uint64_t BeginOffset;
497   uint64_t EndOffset = 0;
498   uint8_t SectionIndex;
499 
500   nlist_base Entry = getSymbolTableEntryBase(this, DRI);
501   uint64_t Value;
502   getSymbolAddress(DRI, Value);
503 
504   BeginOffset = Value;
505 
506   SectionIndex = Entry.n_sect;
507   if (!SectionIndex) {
508     uint32_t flags = getSymbolFlags(DRI);
509     if (flags & SymbolRef::SF_Common)
510       Result = Value;
511     else
512       Result = UnknownAddressOrSize;
513     return object_error::success;
514   }
515   // Unfortunately symbols are unsorted so we need to touch all
516   // symbols from load command
517   for (const SymbolRef &Symbol : symbols()) {
518     DataRefImpl DRI = Symbol.getRawDataRefImpl();
519     Entry = getSymbolTableEntryBase(this, DRI);
520     getSymbolAddress(DRI, Value);
521     if (Entry.n_sect == SectionIndex && Value > BeginOffset)
522       if (!EndOffset || Value < EndOffset)
523         EndOffset = Value;
524   }
525   if (!EndOffset) {
526     uint64_t Size;
527     DataRefImpl Sec;
528     Sec.d.a = SectionIndex-1;
529     getSectionSize(Sec, Size);
530     getSectionAddress(Sec, EndOffset);
531     EndOffset += Size;
532   }
533   Result = EndOffset - BeginOffset;
534   return object_error::success;
535 }
536 
537 error_code MachOObjectFile::getSymbolType(DataRefImpl Symb,
538                                           SymbolRef::Type &Res) const {
539   nlist_base Entry = getSymbolTableEntryBase(this, Symb);
540   uint8_t n_type = Entry.n_type;
541 
542   Res = SymbolRef::ST_Other;
543 
544   // If this is a STAB debugging symbol, we can do nothing more.
545   if (n_type & MachO::N_STAB) {
546     Res = SymbolRef::ST_Debug;
547     return object_error::success;
548   }
549 
550   switch (n_type & MachO::N_TYPE) {
551     case MachO::N_UNDF :
552       Res = SymbolRef::ST_Unknown;
553       break;
554     case MachO::N_SECT :
555       Res = SymbolRef::ST_Function;
556       break;
557   }
558   return object_error::success;
559 }
560 
561 uint32_t MachOObjectFile::getSymbolFlags(DataRefImpl DRI) const {
562   nlist_base Entry = getSymbolTableEntryBase(this, DRI);
563 
564   uint8_t MachOType = Entry.n_type;
565   uint16_t MachOFlags = Entry.n_desc;
566 
567   uint32_t Result = SymbolRef::SF_None;
568 
569   if ((MachOType & MachO::N_TYPE) == MachO::N_UNDF)
570     Result |= SymbolRef::SF_Undefined;
571 
572   if (MachOType & MachO::N_STAB)
573     Result |= SymbolRef::SF_FormatSpecific;
574 
575   if (MachOType & MachO::N_EXT) {
576     Result |= SymbolRef::SF_Global;
577     if ((MachOType & MachO::N_TYPE) == MachO::N_UNDF) {
578       uint64_t Value;
579       getSymbolAddress(DRI, Value);
580       if (Value)
581         Result |= SymbolRef::SF_Common;
582     }
583   }
584 
585   if (MachOFlags & (MachO::N_WEAK_REF | MachO::N_WEAK_DEF))
586     Result |= SymbolRef::SF_Weak;
587 
588   if ((MachOType & MachO::N_TYPE) == MachO::N_ABS)
589     Result |= SymbolRef::SF_Absolute;
590 
591   return Result;
592 }
593 
594 error_code
595 MachOObjectFile::getSymbolSection(DataRefImpl Symb,
596                                   section_iterator &Res) const {
597   nlist_base Entry = getSymbolTableEntryBase(this, Symb);
598   uint8_t index = Entry.n_sect;
599 
600   if (index == 0) {
601     Res = section_end();
602   } else {
603     DataRefImpl DRI;
604     DRI.d.a = index - 1;
605     Res = section_iterator(SectionRef(DRI, this));
606   }
607 
608   return object_error::success;
609 }
610 
611 void MachOObjectFile::moveSectionNext(DataRefImpl &Sec) const {
612   Sec.d.a++;
613 }
614 
615 error_code
616 MachOObjectFile::getSectionName(DataRefImpl Sec, StringRef &Result) const {
617   ArrayRef<char> Raw = getSectionRawName(Sec);
618   Result = parseSegmentOrSectionName(Raw.data());
619   return object_error::success;
620 }
621 
622 error_code
623 MachOObjectFile::getSectionAddress(DataRefImpl Sec, uint64_t &Res) const {
624   if (is64Bit()) {
625     MachO::section_64 Sect = getSection64(Sec);
626     Res = Sect.addr;
627   } else {
628     MachO::section Sect = getSection(Sec);
629     Res = Sect.addr;
630   }
631   return object_error::success;
632 }
633 
634 error_code
635 MachOObjectFile::getSectionSize(DataRefImpl Sec, uint64_t &Res) const {
636   if (is64Bit()) {
637     MachO::section_64 Sect = getSection64(Sec);
638     Res = Sect.size;
639   } else {
640     MachO::section Sect = getSection(Sec);
641     Res = Sect.size;
642   }
643 
644   return object_error::success;
645 }
646 
647 error_code
648 MachOObjectFile::getSectionContents(DataRefImpl Sec, StringRef &Res) const {
649   uint32_t Offset;
650   uint64_t Size;
651 
652   if (is64Bit()) {
653     MachO::section_64 Sect = getSection64(Sec);
654     Offset = Sect.offset;
655     Size = Sect.size;
656   } else {
657     MachO::section Sect = getSection(Sec);
658     Offset = Sect.offset;
659     Size = Sect.size;
660   }
661 
662   Res = this->getData().substr(Offset, Size);
663   return object_error::success;
664 }
665 
666 error_code
667 MachOObjectFile::getSectionAlignment(DataRefImpl Sec, uint64_t &Res) const {
668   uint32_t Align;
669   if (is64Bit()) {
670     MachO::section_64 Sect = getSection64(Sec);
671     Align = Sect.align;
672   } else {
673     MachO::section Sect = getSection(Sec);
674     Align = Sect.align;
675   }
676 
677   Res = uint64_t(1) << Align;
678   return object_error::success;
679 }
680 
681 error_code
682 MachOObjectFile::isSectionText(DataRefImpl Sec, bool &Res) const {
683   uint32_t Flags = getSectionFlags(this, Sec);
684   Res = Flags & MachO::S_ATTR_PURE_INSTRUCTIONS;
685   return object_error::success;
686 }
687 
688 error_code MachOObjectFile::isSectionData(DataRefImpl DRI, bool &Result) const {
689   // FIXME: Unimplemented.
690   Result = false;
691   return object_error::success;
692 }
693 
694 error_code MachOObjectFile::isSectionBSS(DataRefImpl DRI, bool &Result) const {
695   // FIXME: Unimplemented.
696   Result = false;
697   return object_error::success;
698 }
699 
700 error_code
701 MachOObjectFile::isSectionRequiredForExecution(DataRefImpl Sec,
702                                                bool &Result) const {
703   // FIXME: Unimplemented.
704   Result = true;
705   return object_error::success;
706 }
707 
708 error_code MachOObjectFile::isSectionVirtual(DataRefImpl Sec,
709                                              bool &Result) const {
710   // FIXME: Unimplemented.
711   Result = false;
712   return object_error::success;
713 }
714 
715 error_code
716 MachOObjectFile::isSectionZeroInit(DataRefImpl Sec, bool &Res) const {
717   uint32_t Flags = getSectionFlags(this, Sec);
718   unsigned SectionType = Flags & MachO::SECTION_TYPE;
719   Res = SectionType == MachO::S_ZEROFILL ||
720     SectionType == MachO::S_GB_ZEROFILL;
721   return object_error::success;
722 }
723 
724 error_code MachOObjectFile::isSectionReadOnlyData(DataRefImpl Sec,
725                                                   bool &Result) const {
726   // Consider using the code from isSectionText to look for __const sections.
727   // Alternately, emit S_ATTR_PURE_INSTRUCTIONS and/or S_ATTR_SOME_INSTRUCTIONS
728   // to use section attributes to distinguish code from data.
729 
730   // FIXME: Unimplemented.
731   Result = false;
732   return object_error::success;
733 }
734 
735 error_code
736 MachOObjectFile::sectionContainsSymbol(DataRefImpl Sec, DataRefImpl Symb,
737                                        bool &Result) const {
738   SymbolRef::Type ST;
739   this->getSymbolType(Symb, ST);
740   if (ST == SymbolRef::ST_Unknown) {
741     Result = false;
742     return object_error::success;
743   }
744 
745   uint64_t SectBegin, SectEnd;
746   getSectionAddress(Sec, SectBegin);
747   getSectionSize(Sec, SectEnd);
748   SectEnd += SectBegin;
749 
750   uint64_t SymAddr;
751   getSymbolAddress(Symb, SymAddr);
752   Result = (SymAddr >= SectBegin) && (SymAddr < SectEnd);
753 
754   return object_error::success;
755 }
756 
757 relocation_iterator MachOObjectFile::section_rel_begin(DataRefImpl Sec) const {
758   DataRefImpl Ret;
759   Ret.d.a = Sec.d.a;
760   Ret.d.b = 0;
761   return relocation_iterator(RelocationRef(Ret, this));
762 }
763 
764 relocation_iterator
765 MachOObjectFile::section_rel_end(DataRefImpl Sec) const {
766   uint32_t Num;
767   if (is64Bit()) {
768     MachO::section_64 Sect = getSection64(Sec);
769     Num = Sect.nreloc;
770   } else {
771     MachO::section Sect = getSection(Sec);
772     Num = Sect.nreloc;
773   }
774 
775   DataRefImpl Ret;
776   Ret.d.a = Sec.d.a;
777   Ret.d.b = Num;
778   return relocation_iterator(RelocationRef(Ret, this));
779 }
780 
781 void MachOObjectFile::moveRelocationNext(DataRefImpl &Rel) const {
782   ++Rel.d.b;
783 }
784 
785 error_code
786 MachOObjectFile::getRelocationAddress(DataRefImpl Rel, uint64_t &Res) const {
787   uint64_t Offset;
788   getRelocationOffset(Rel, Offset);
789 
790   DataRefImpl Sec;
791   Sec.d.a = Rel.d.a;
792   uint64_t SecAddress;
793   getSectionAddress(Sec, SecAddress);
794   Res = SecAddress + Offset;
795   return object_error::success;
796 }
797 
798 error_code MachOObjectFile::getRelocationOffset(DataRefImpl Rel,
799                                                 uint64_t &Res) const {
800   assert(getHeader().filetype == MachO::MH_OBJECT &&
801          "Only implemented for MH_OBJECT");
802   MachO::any_relocation_info RE = getRelocation(Rel);
803   Res = getAnyRelocationAddress(RE);
804   return object_error::success;
805 }
806 
807 symbol_iterator
808 MachOObjectFile::getRelocationSymbol(DataRefImpl Rel) const {
809   MachO::any_relocation_info RE = getRelocation(Rel);
810   uint32_t SymbolIdx = getPlainRelocationSymbolNum(RE);
811   bool isExtern = getPlainRelocationExternal(RE);
812   if (!isExtern)
813     return symbol_end();
814 
815   MachO::symtab_command S = getSymtabLoadCommand();
816   unsigned SymbolTableEntrySize = is64Bit() ?
817     sizeof(MachO::nlist_64) :
818     sizeof(MachO::nlist);
819   uint64_t Offset = S.symoff + SymbolIdx * SymbolTableEntrySize;
820   DataRefImpl Sym;
821   Sym.p = reinterpret_cast<uintptr_t>(getPtr(this, Offset));
822   return symbol_iterator(SymbolRef(Sym, this));
823 }
824 
825 error_code MachOObjectFile::getRelocationType(DataRefImpl Rel,
826                                               uint64_t &Res) const {
827   MachO::any_relocation_info RE = getRelocation(Rel);
828   Res = getAnyRelocationType(RE);
829   return object_error::success;
830 }
831 
832 error_code
833 MachOObjectFile::getRelocationTypeName(DataRefImpl Rel,
834                                        SmallVectorImpl<char> &Result) const {
835   StringRef res;
836   uint64_t RType;
837   getRelocationType(Rel, RType);
838 
839   unsigned Arch = this->getArch();
840 
841   switch (Arch) {
842     case Triple::x86: {
843       static const char *const Table[] =  {
844         "GENERIC_RELOC_VANILLA",
845         "GENERIC_RELOC_PAIR",
846         "GENERIC_RELOC_SECTDIFF",
847         "GENERIC_RELOC_PB_LA_PTR",
848         "GENERIC_RELOC_LOCAL_SECTDIFF",
849         "GENERIC_RELOC_TLV" };
850 
851       if (RType > 5)
852         res = "Unknown";
853       else
854         res = Table[RType];
855       break;
856     }
857     case Triple::x86_64: {
858       static const char *const Table[] =  {
859         "X86_64_RELOC_UNSIGNED",
860         "X86_64_RELOC_SIGNED",
861         "X86_64_RELOC_BRANCH",
862         "X86_64_RELOC_GOT_LOAD",
863         "X86_64_RELOC_GOT",
864         "X86_64_RELOC_SUBTRACTOR",
865         "X86_64_RELOC_SIGNED_1",
866         "X86_64_RELOC_SIGNED_2",
867         "X86_64_RELOC_SIGNED_4",
868         "X86_64_RELOC_TLV" };
869 
870       if (RType > 9)
871         res = "Unknown";
872       else
873         res = Table[RType];
874       break;
875     }
876     case Triple::arm: {
877       static const char *const Table[] =  {
878         "ARM_RELOC_VANILLA",
879         "ARM_RELOC_PAIR",
880         "ARM_RELOC_SECTDIFF",
881         "ARM_RELOC_LOCAL_SECTDIFF",
882         "ARM_RELOC_PB_LA_PTR",
883         "ARM_RELOC_BR24",
884         "ARM_THUMB_RELOC_BR22",
885         "ARM_THUMB_32BIT_BRANCH",
886         "ARM_RELOC_HALF",
887         "ARM_RELOC_HALF_SECTDIFF" };
888 
889       if (RType > 9)
890         res = "Unknown";
891       else
892         res = Table[RType];
893       break;
894     }
895     case Triple::arm64:
896     case Triple::aarch64: {
897       static const char *const Table[] = {
898         "ARM64_RELOC_UNSIGNED",           "ARM64_RELOC_SUBTRACTOR",
899         "ARM64_RELOC_BRANCH26",           "ARM64_RELOC_PAGE21",
900         "ARM64_RELOC_PAGEOFF12",          "ARM64_RELOC_GOT_LOAD_PAGE21",
901         "ARM64_RELOC_GOT_LOAD_PAGEOFF12", "ARM64_RELOC_POINTER_TO_GOT",
902         "ARM64_RELOC_TLVP_LOAD_PAGE21",   "ARM64_RELOC_TLVP_LOAD_PAGEOFF12",
903         "ARM64_RELOC_ADDEND"
904       };
905 
906       if (RType >= array_lengthof(Table))
907         res = "Unknown";
908       else
909         res = Table[RType];
910       break;
911     }
912     case Triple::ppc: {
913       static const char *const Table[] =  {
914         "PPC_RELOC_VANILLA",
915         "PPC_RELOC_PAIR",
916         "PPC_RELOC_BR14",
917         "PPC_RELOC_BR24",
918         "PPC_RELOC_HI16",
919         "PPC_RELOC_LO16",
920         "PPC_RELOC_HA16",
921         "PPC_RELOC_LO14",
922         "PPC_RELOC_SECTDIFF",
923         "PPC_RELOC_PB_LA_PTR",
924         "PPC_RELOC_HI16_SECTDIFF",
925         "PPC_RELOC_LO16_SECTDIFF",
926         "PPC_RELOC_HA16_SECTDIFF",
927         "PPC_RELOC_JBSR",
928         "PPC_RELOC_LO14_SECTDIFF",
929         "PPC_RELOC_LOCAL_SECTDIFF" };
930 
931       if (RType > 15)
932         res = "Unknown";
933       else
934         res = Table[RType];
935       break;
936     }
937     case Triple::UnknownArch:
938       res = "Unknown";
939       break;
940   }
941   Result.append(res.begin(), res.end());
942   return object_error::success;
943 }
944 
945 error_code
946 MachOObjectFile::getRelocationValueString(DataRefImpl Rel,
947                                           SmallVectorImpl<char> &Result) const {
948   MachO::any_relocation_info RE = getRelocation(Rel);
949 
950   unsigned Arch = this->getArch();
951 
952   std::string fmtbuf;
953   raw_string_ostream fmt(fmtbuf);
954   unsigned Type = this->getAnyRelocationType(RE);
955   bool IsPCRel = this->getAnyRelocationPCRel(RE);
956 
957   // Determine any addends that should be displayed with the relocation.
958   // These require decoding the relocation type, which is triple-specific.
959 
960   // X86_64 has entirely custom relocation types.
961   if (Arch == Triple::x86_64) {
962     bool isPCRel = getAnyRelocationPCRel(RE);
963 
964     switch (Type) {
965       case MachO::X86_64_RELOC_GOT_LOAD:
966       case MachO::X86_64_RELOC_GOT: {
967         printRelocationTargetName(this, RE, fmt);
968         fmt << "@GOT";
969         if (isPCRel) fmt << "PCREL";
970         break;
971       }
972       case MachO::X86_64_RELOC_SUBTRACTOR: {
973         DataRefImpl RelNext = Rel;
974         moveRelocationNext(RelNext);
975         MachO::any_relocation_info RENext = getRelocation(RelNext);
976 
977         // X86_64_RELOC_SUBTRACTOR must be followed by a relocation of type
978         // X86_64_RELOC_UNSIGNED.
979         // NOTE: Scattered relocations don't exist on x86_64.
980         unsigned RType = getAnyRelocationType(RENext);
981         if (RType != MachO::X86_64_RELOC_UNSIGNED)
982           report_fatal_error("Expected X86_64_RELOC_UNSIGNED after "
983                              "X86_64_RELOC_SUBTRACTOR.");
984 
985         // The X86_64_RELOC_UNSIGNED contains the minuend symbol;
986         // X86_64_RELOC_SUBTRACTOR contains the subtrahend.
987         printRelocationTargetName(this, RENext, fmt);
988         fmt << "-";
989         printRelocationTargetName(this, RE, fmt);
990         break;
991       }
992       case MachO::X86_64_RELOC_TLV:
993         printRelocationTargetName(this, RE, fmt);
994         fmt << "@TLV";
995         if (isPCRel) fmt << "P";
996         break;
997       case MachO::X86_64_RELOC_SIGNED_1:
998         printRelocationTargetName(this, RE, fmt);
999         fmt << "-1";
1000         break;
1001       case MachO::X86_64_RELOC_SIGNED_2:
1002         printRelocationTargetName(this, RE, fmt);
1003         fmt << "-2";
1004         break;
1005       case MachO::X86_64_RELOC_SIGNED_4:
1006         printRelocationTargetName(this, RE, fmt);
1007         fmt << "-4";
1008         break;
1009       default:
1010         printRelocationTargetName(this, RE, fmt);
1011         break;
1012     }
1013   // X86 and ARM share some relocation types in common.
1014   } else if (Arch == Triple::x86 || Arch == Triple::arm ||
1015              Arch == Triple::ppc) {
1016     // Generic relocation types...
1017     switch (Type) {
1018       case MachO::GENERIC_RELOC_PAIR: // prints no info
1019         return object_error::success;
1020       case MachO::GENERIC_RELOC_SECTDIFF: {
1021         DataRefImpl RelNext = Rel;
1022         moveRelocationNext(RelNext);
1023         MachO::any_relocation_info RENext = getRelocation(RelNext);
1024 
1025         // X86 sect diff's must be followed by a relocation of type
1026         // GENERIC_RELOC_PAIR.
1027         unsigned RType = getAnyRelocationType(RENext);
1028 
1029         if (RType != MachO::GENERIC_RELOC_PAIR)
1030           report_fatal_error("Expected GENERIC_RELOC_PAIR after "
1031                              "GENERIC_RELOC_SECTDIFF.");
1032 
1033         printRelocationTargetName(this, RE, fmt);
1034         fmt << "-";
1035         printRelocationTargetName(this, RENext, fmt);
1036         break;
1037       }
1038     }
1039 
1040     if (Arch == Triple::x86 || Arch == Triple::ppc) {
1041       switch (Type) {
1042         case MachO::GENERIC_RELOC_LOCAL_SECTDIFF: {
1043           DataRefImpl RelNext = Rel;
1044           moveRelocationNext(RelNext);
1045           MachO::any_relocation_info RENext = getRelocation(RelNext);
1046 
1047           // X86 sect diff's must be followed by a relocation of type
1048           // GENERIC_RELOC_PAIR.
1049           unsigned RType = getAnyRelocationType(RENext);
1050           if (RType != MachO::GENERIC_RELOC_PAIR)
1051             report_fatal_error("Expected GENERIC_RELOC_PAIR after "
1052                                "GENERIC_RELOC_LOCAL_SECTDIFF.");
1053 
1054           printRelocationTargetName(this, RE, fmt);
1055           fmt << "-";
1056           printRelocationTargetName(this, RENext, fmt);
1057           break;
1058         }
1059         case MachO::GENERIC_RELOC_TLV: {
1060           printRelocationTargetName(this, RE, fmt);
1061           fmt << "@TLV";
1062           if (IsPCRel) fmt << "P";
1063           break;
1064         }
1065         default:
1066           printRelocationTargetName(this, RE, fmt);
1067       }
1068     } else { // ARM-specific relocations
1069       switch (Type) {
1070         case MachO::ARM_RELOC_HALF:
1071         case MachO::ARM_RELOC_HALF_SECTDIFF: {
1072           // Half relocations steal a bit from the length field to encode
1073           // whether this is an upper16 or a lower16 relocation.
1074           bool isUpper = getAnyRelocationLength(RE) >> 1;
1075 
1076           if (isUpper)
1077             fmt << ":upper16:(";
1078           else
1079             fmt << ":lower16:(";
1080           printRelocationTargetName(this, RE, fmt);
1081 
1082           DataRefImpl RelNext = Rel;
1083           moveRelocationNext(RelNext);
1084           MachO::any_relocation_info RENext = getRelocation(RelNext);
1085 
1086           // ARM half relocs must be followed by a relocation of type
1087           // ARM_RELOC_PAIR.
1088           unsigned RType = getAnyRelocationType(RENext);
1089           if (RType != MachO::ARM_RELOC_PAIR)
1090             report_fatal_error("Expected ARM_RELOC_PAIR after "
1091                                "ARM_RELOC_HALF");
1092 
1093           // NOTE: The half of the target virtual address is stashed in the
1094           // address field of the secondary relocation, but we can't reverse
1095           // engineer the constant offset from it without decoding the movw/movt
1096           // instruction to find the other half in its immediate field.
1097 
1098           // ARM_RELOC_HALF_SECTDIFF encodes the second section in the
1099           // symbol/section pointer of the follow-on relocation.
1100           if (Type == MachO::ARM_RELOC_HALF_SECTDIFF) {
1101             fmt << "-";
1102             printRelocationTargetName(this, RENext, fmt);
1103           }
1104 
1105           fmt << ")";
1106           break;
1107         }
1108         default: {
1109           printRelocationTargetName(this, RE, fmt);
1110         }
1111       }
1112     }
1113   } else
1114     printRelocationTargetName(this, RE, fmt);
1115 
1116   fmt.flush();
1117   Result.append(fmtbuf.begin(), fmtbuf.end());
1118   return object_error::success;
1119 }
1120 
1121 error_code
1122 MachOObjectFile::getRelocationHidden(DataRefImpl Rel, bool &Result) const {
1123   unsigned Arch = getArch();
1124   uint64_t Type;
1125   getRelocationType(Rel, Type);
1126 
1127   Result = false;
1128 
1129   // On arches that use the generic relocations, GENERIC_RELOC_PAIR
1130   // is always hidden.
1131   if (Arch == Triple::x86 || Arch == Triple::arm || Arch == Triple::ppc) {
1132     if (Type == MachO::GENERIC_RELOC_PAIR) Result = true;
1133   } else if (Arch == Triple::x86_64) {
1134     // On x86_64, X86_64_RELOC_UNSIGNED is hidden only when it follows
1135     // an X86_64_RELOC_SUBTRACTOR.
1136     if (Type == MachO::X86_64_RELOC_UNSIGNED && Rel.d.a > 0) {
1137       DataRefImpl RelPrev = Rel;
1138       RelPrev.d.a--;
1139       uint64_t PrevType;
1140       getRelocationType(RelPrev, PrevType);
1141       if (PrevType == MachO::X86_64_RELOC_SUBTRACTOR)
1142         Result = true;
1143     }
1144   }
1145 
1146   return object_error::success;
1147 }
1148 
1149 error_code MachOObjectFile::getLibraryNext(DataRefImpl LibData,
1150                                            LibraryRef &Res) const {
1151   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1152 }
1153 
1154 error_code MachOObjectFile::getLibraryPath(DataRefImpl LibData,
1155                                            StringRef &Res) const {
1156   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1157 }
1158 
1159 basic_symbol_iterator MachOObjectFile::symbol_begin_impl() const {
1160   DataRefImpl DRI;
1161   if (!SymtabLoadCmd)
1162     return basic_symbol_iterator(SymbolRef(DRI, this));
1163 
1164   MachO::symtab_command Symtab = getSymtabLoadCommand();
1165   DRI.p = reinterpret_cast<uintptr_t>(getPtr(this, Symtab.symoff));
1166   return basic_symbol_iterator(SymbolRef(DRI, this));
1167 }
1168 
1169 basic_symbol_iterator MachOObjectFile::symbol_end_impl() const {
1170   DataRefImpl DRI;
1171   if (!SymtabLoadCmd)
1172     return basic_symbol_iterator(SymbolRef(DRI, this));
1173 
1174   MachO::symtab_command Symtab = getSymtabLoadCommand();
1175   unsigned SymbolTableEntrySize = is64Bit() ?
1176     sizeof(MachO::nlist_64) :
1177     sizeof(MachO::nlist);
1178   unsigned Offset = Symtab.symoff +
1179     Symtab.nsyms * SymbolTableEntrySize;
1180   DRI.p = reinterpret_cast<uintptr_t>(getPtr(this, Offset));
1181   return basic_symbol_iterator(SymbolRef(DRI, this));
1182 }
1183 
1184 section_iterator MachOObjectFile::section_begin() const {
1185   DataRefImpl DRI;
1186   return section_iterator(SectionRef(DRI, this));
1187 }
1188 
1189 section_iterator MachOObjectFile::section_end() const {
1190   DataRefImpl DRI;
1191   DRI.d.a = Sections.size();
1192   return section_iterator(SectionRef(DRI, this));
1193 }
1194 
1195 library_iterator MachOObjectFile::needed_library_begin() const {
1196   // TODO: implement
1197   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1198 }
1199 
1200 library_iterator MachOObjectFile::needed_library_end() const {
1201   // TODO: implement
1202   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1203 }
1204 
1205 uint8_t MachOObjectFile::getBytesInAddress() const {
1206   return is64Bit() ? 8 : 4;
1207 }
1208 
1209 StringRef MachOObjectFile::getFileFormatName() const {
1210   unsigned CPUType = getCPUType(this);
1211   if (!is64Bit()) {
1212     switch (CPUType) {
1213     case llvm::MachO::CPU_TYPE_I386:
1214       return "Mach-O 32-bit i386";
1215     case llvm::MachO::CPU_TYPE_ARM:
1216       return "Mach-O arm";
1217     case llvm::MachO::CPU_TYPE_POWERPC:
1218       return "Mach-O 32-bit ppc";
1219     default:
1220       assert((CPUType & llvm::MachO::CPU_ARCH_ABI64) == 0 &&
1221              "64-bit object file when we're not 64-bit?");
1222       return "Mach-O 32-bit unknown";
1223     }
1224   }
1225 
1226   // Make sure the cpu type has the correct mask.
1227   assert((CPUType & llvm::MachO::CPU_ARCH_ABI64)
1228          == llvm::MachO::CPU_ARCH_ABI64 &&
1229          "32-bit object file when we're 64-bit?");
1230 
1231   switch (CPUType) {
1232   case llvm::MachO::CPU_TYPE_X86_64:
1233     return "Mach-O 64-bit x86-64";
1234   case llvm::MachO::CPU_TYPE_ARM64:
1235     return "Mach-O arm64";
1236   case llvm::MachO::CPU_TYPE_POWERPC64:
1237     return "Mach-O 64-bit ppc64";
1238   default:
1239     return "Mach-O 64-bit unknown";
1240   }
1241 }
1242 
1243 Triple::ArchType MachOObjectFile::getArch(uint32_t CPUType) {
1244   switch (CPUType) {
1245   case llvm::MachO::CPU_TYPE_I386:
1246     return Triple::x86;
1247   case llvm::MachO::CPU_TYPE_X86_64:
1248     return Triple::x86_64;
1249   case llvm::MachO::CPU_TYPE_ARM:
1250     return Triple::arm;
1251   case llvm::MachO::CPU_TYPE_ARM64:
1252     return Triple::arm64;
1253   case llvm::MachO::CPU_TYPE_POWERPC:
1254     return Triple::ppc;
1255   case llvm::MachO::CPU_TYPE_POWERPC64:
1256     return Triple::ppc64;
1257   default:
1258     return Triple::UnknownArch;
1259   }
1260 }
1261 
1262 unsigned MachOObjectFile::getArch() const {
1263   return getArch(getCPUType(this));
1264 }
1265 
1266 StringRef MachOObjectFile::getLoadName() const {
1267   // TODO: Implement
1268   report_fatal_error("get_load_name() unimplemented in MachOObjectFile");
1269 }
1270 
1271 relocation_iterator MachOObjectFile::section_rel_begin(unsigned Index) const {
1272   DataRefImpl DRI;
1273   DRI.d.a = Index;
1274   return section_rel_begin(DRI);
1275 }
1276 
1277 relocation_iterator MachOObjectFile::section_rel_end(unsigned Index) const {
1278   DataRefImpl DRI;
1279   DRI.d.a = Index;
1280   return section_rel_end(DRI);
1281 }
1282 
1283 dice_iterator MachOObjectFile::begin_dices() const {
1284   DataRefImpl DRI;
1285   if (!DataInCodeLoadCmd)
1286     return dice_iterator(DiceRef(DRI, this));
1287 
1288   MachO::linkedit_data_command DicLC = getDataInCodeLoadCommand();
1289   DRI.p = reinterpret_cast<uintptr_t>(getPtr(this, DicLC.dataoff));
1290   return dice_iterator(DiceRef(DRI, this));
1291 }
1292 
1293 dice_iterator MachOObjectFile::end_dices() const {
1294   DataRefImpl DRI;
1295   if (!DataInCodeLoadCmd)
1296     return dice_iterator(DiceRef(DRI, this));
1297 
1298   MachO::linkedit_data_command DicLC = getDataInCodeLoadCommand();
1299   unsigned Offset = DicLC.dataoff + DicLC.datasize;
1300   DRI.p = reinterpret_cast<uintptr_t>(getPtr(this, Offset));
1301   return dice_iterator(DiceRef(DRI, this));
1302 }
1303 
1304 StringRef
1305 MachOObjectFile::getSectionFinalSegmentName(DataRefImpl Sec) const {
1306   ArrayRef<char> Raw = getSectionRawFinalSegmentName(Sec);
1307   return parseSegmentOrSectionName(Raw.data());
1308 }
1309 
1310 ArrayRef<char>
1311 MachOObjectFile::getSectionRawName(DataRefImpl Sec) const {
1312   const section_base *Base =
1313     reinterpret_cast<const section_base *>(Sections[Sec.d.a]);
1314   return ArrayRef<char>(Base->sectname);
1315 }
1316 
1317 ArrayRef<char>
1318 MachOObjectFile::getSectionRawFinalSegmentName(DataRefImpl Sec) const {
1319   const section_base *Base =
1320     reinterpret_cast<const section_base *>(Sections[Sec.d.a]);
1321   return ArrayRef<char>(Base->segname);
1322 }
1323 
1324 bool
1325 MachOObjectFile::isRelocationScattered(const MachO::any_relocation_info &RE)
1326   const {
1327   if (getCPUType(this) == MachO::CPU_TYPE_X86_64)
1328     return false;
1329   return getPlainRelocationAddress(RE) & MachO::R_SCATTERED;
1330 }
1331 
1332 unsigned MachOObjectFile::getPlainRelocationSymbolNum(
1333     const MachO::any_relocation_info &RE) const {
1334   if (isLittleEndian())
1335     return RE.r_word1 & 0xffffff;
1336   return RE.r_word1 >> 8;
1337 }
1338 
1339 bool MachOObjectFile::getPlainRelocationExternal(
1340     const MachO::any_relocation_info &RE) const {
1341   if (isLittleEndian())
1342     return (RE.r_word1 >> 27) & 1;
1343   return (RE.r_word1 >> 4) & 1;
1344 }
1345 
1346 bool MachOObjectFile::getScatteredRelocationScattered(
1347     const MachO::any_relocation_info &RE) const {
1348   return RE.r_word0 >> 31;
1349 }
1350 
1351 uint32_t MachOObjectFile::getScatteredRelocationValue(
1352     const MachO::any_relocation_info &RE) const {
1353   return RE.r_word1;
1354 }
1355 
1356 unsigned MachOObjectFile::getAnyRelocationAddress(
1357     const MachO::any_relocation_info &RE) const {
1358   if (isRelocationScattered(RE))
1359     return getScatteredRelocationAddress(RE);
1360   return getPlainRelocationAddress(RE);
1361 }
1362 
1363 unsigned MachOObjectFile::getAnyRelocationPCRel(
1364     const MachO::any_relocation_info &RE) const {
1365   if (isRelocationScattered(RE))
1366     return getScatteredRelocationPCRel(this, RE);
1367   return getPlainRelocationPCRel(this, RE);
1368 }
1369 
1370 unsigned MachOObjectFile::getAnyRelocationLength(
1371     const MachO::any_relocation_info &RE) const {
1372   if (isRelocationScattered(RE))
1373     return getScatteredRelocationLength(RE);
1374   return getPlainRelocationLength(this, RE);
1375 }
1376 
1377 unsigned
1378 MachOObjectFile::getAnyRelocationType(
1379                                    const MachO::any_relocation_info &RE) const {
1380   if (isRelocationScattered(RE))
1381     return getScatteredRelocationType(RE);
1382   return getPlainRelocationType(this, RE);
1383 }
1384 
1385 SectionRef
1386 MachOObjectFile::getRelocationSection(
1387                                    const MachO::any_relocation_info &RE) const {
1388   if (isRelocationScattered(RE) || getPlainRelocationExternal(RE))
1389     return *section_end();
1390   unsigned SecNum = getPlainRelocationSymbolNum(RE) - 1;
1391   DataRefImpl DRI;
1392   DRI.d.a = SecNum;
1393   return SectionRef(DRI, this);
1394 }
1395 
1396 MachOObjectFile::LoadCommandInfo
1397 MachOObjectFile::getFirstLoadCommandInfo() const {
1398   MachOObjectFile::LoadCommandInfo Load;
1399 
1400   unsigned HeaderSize = is64Bit() ? sizeof(MachO::mach_header_64) :
1401                                     sizeof(MachO::mach_header);
1402   Load.Ptr = getPtr(this, HeaderSize);
1403   Load.C = getStruct<MachO::load_command>(this, Load.Ptr);
1404   return Load;
1405 }
1406 
1407 MachOObjectFile::LoadCommandInfo
1408 MachOObjectFile::getNextLoadCommandInfo(const LoadCommandInfo &L) const {
1409   MachOObjectFile::LoadCommandInfo Next;
1410   Next.Ptr = L.Ptr + L.C.cmdsize;
1411   Next.C = getStruct<MachO::load_command>(this, Next.Ptr);
1412   return Next;
1413 }
1414 
1415 MachO::section MachOObjectFile::getSection(DataRefImpl DRI) const {
1416   return getStruct<MachO::section>(this, Sections[DRI.d.a]);
1417 }
1418 
1419 MachO::section_64 MachOObjectFile::getSection64(DataRefImpl DRI) const {
1420   return getStruct<MachO::section_64>(this, Sections[DRI.d.a]);
1421 }
1422 
1423 MachO::section MachOObjectFile::getSection(const LoadCommandInfo &L,
1424                                            unsigned Index) const {
1425   const char *Sec = getSectionPtr(this, L, Index);
1426   return getStruct<MachO::section>(this, Sec);
1427 }
1428 
1429 MachO::section_64 MachOObjectFile::getSection64(const LoadCommandInfo &L,
1430                                                 unsigned Index) const {
1431   const char *Sec = getSectionPtr(this, L, Index);
1432   return getStruct<MachO::section_64>(this, Sec);
1433 }
1434 
1435 MachO::nlist
1436 MachOObjectFile::getSymbolTableEntry(DataRefImpl DRI) const {
1437   const char *P = reinterpret_cast<const char *>(DRI.p);
1438   return getStruct<MachO::nlist>(this, P);
1439 }
1440 
1441 MachO::nlist_64
1442 MachOObjectFile::getSymbol64TableEntry(DataRefImpl DRI) const {
1443   const char *P = reinterpret_cast<const char *>(DRI.p);
1444   return getStruct<MachO::nlist_64>(this, P);
1445 }
1446 
1447 MachO::linkedit_data_command
1448 MachOObjectFile::getLinkeditDataLoadCommand(const LoadCommandInfo &L) const {
1449   return getStruct<MachO::linkedit_data_command>(this, L.Ptr);
1450 }
1451 
1452 MachO::segment_command
1453 MachOObjectFile::getSegmentLoadCommand(const LoadCommandInfo &L) const {
1454   return getStruct<MachO::segment_command>(this, L.Ptr);
1455 }
1456 
1457 MachO::segment_command_64
1458 MachOObjectFile::getSegment64LoadCommand(const LoadCommandInfo &L) const {
1459   return getStruct<MachO::segment_command_64>(this, L.Ptr);
1460 }
1461 
1462 MachO::linker_options_command
1463 MachOObjectFile::getLinkerOptionsLoadCommand(const LoadCommandInfo &L) const {
1464   return getStruct<MachO::linker_options_command>(this, L.Ptr);
1465 }
1466 
1467 MachO::version_min_command
1468 MachOObjectFile::getVersionMinLoadCommand(const LoadCommandInfo &L) const {
1469   return getStruct<MachO::version_min_command>(this, L.Ptr);
1470 }
1471 
1472 MachO::any_relocation_info
1473 MachOObjectFile::getRelocation(DataRefImpl Rel) const {
1474   DataRefImpl Sec;
1475   Sec.d.a = Rel.d.a;
1476   uint32_t Offset;
1477   if (is64Bit()) {
1478     MachO::section_64 Sect = getSection64(Sec);
1479     Offset = Sect.reloff;
1480   } else {
1481     MachO::section Sect = getSection(Sec);
1482     Offset = Sect.reloff;
1483   }
1484 
1485   auto P = reinterpret_cast<const MachO::any_relocation_info *>(
1486       getPtr(this, Offset)) + Rel.d.b;
1487   return getStruct<MachO::any_relocation_info>(
1488       this, reinterpret_cast<const char *>(P));
1489 }
1490 
1491 MachO::data_in_code_entry
1492 MachOObjectFile::getDice(DataRefImpl Rel) const {
1493   const char *P = reinterpret_cast<const char *>(Rel.p);
1494   return getStruct<MachO::data_in_code_entry>(this, P);
1495 }
1496 
1497 MachO::mach_header MachOObjectFile::getHeader() const {
1498   return getStruct<MachO::mach_header>(this, getPtr(this, 0));
1499 }
1500 
1501 MachO::mach_header_64 MachOObjectFile::getHeader64() const {
1502   return getStruct<MachO::mach_header_64>(this, getPtr(this, 0));
1503 }
1504 
1505 uint32_t MachOObjectFile::getIndirectSymbolTableEntry(
1506                                              const MachO::dysymtab_command &DLC,
1507                                              unsigned Index) const {
1508   uint64_t Offset = DLC.indirectsymoff + Index * sizeof(uint32_t);
1509   return getStruct<uint32_t>(this, getPtr(this, Offset));
1510 }
1511 
1512 MachO::data_in_code_entry
1513 MachOObjectFile::getDataInCodeTableEntry(uint32_t DataOffset,
1514                                          unsigned Index) const {
1515   uint64_t Offset = DataOffset + Index * sizeof(MachO::data_in_code_entry);
1516   return getStruct<MachO::data_in_code_entry>(this, getPtr(this, Offset));
1517 }
1518 
1519 MachO::symtab_command MachOObjectFile::getSymtabLoadCommand() const {
1520   return getStruct<MachO::symtab_command>(this, SymtabLoadCmd);
1521 }
1522 
1523 MachO::dysymtab_command MachOObjectFile::getDysymtabLoadCommand() const {
1524   return getStruct<MachO::dysymtab_command>(this, DysymtabLoadCmd);
1525 }
1526 
1527 MachO::linkedit_data_command
1528 MachOObjectFile::getDataInCodeLoadCommand() const {
1529   if (DataInCodeLoadCmd)
1530     return getStruct<MachO::linkedit_data_command>(this, DataInCodeLoadCmd);
1531 
1532   // If there is no DataInCodeLoadCmd return a load command with zero'ed fields.
1533   MachO::linkedit_data_command Cmd;
1534   Cmd.cmd = MachO::LC_DATA_IN_CODE;
1535   Cmd.cmdsize = sizeof(MachO::linkedit_data_command);
1536   Cmd.dataoff = 0;
1537   Cmd.datasize = 0;
1538   return Cmd;
1539 }
1540 
1541 StringRef MachOObjectFile::getStringTableData() const {
1542   MachO::symtab_command S = getSymtabLoadCommand();
1543   return getData().substr(S.stroff, S.strsize);
1544 }
1545 
1546 bool MachOObjectFile::is64Bit() const {
1547   return getType() == getMachOType(false, true) ||
1548     getType() == getMachOType(true, true);
1549 }
1550 
1551 void MachOObjectFile::ReadULEB128s(uint64_t Index,
1552                                    SmallVectorImpl<uint64_t> &Out) const {
1553   DataExtractor extractor(ObjectFile::getData(), true, 0);
1554 
1555   uint32_t offset = Index;
1556   uint64_t data = 0;
1557   while (uint64_t delta = extractor.getULEB128(&offset)) {
1558     data += delta;
1559     Out.push_back(data);
1560   }
1561 }
1562 
1563 ErrorOr<ObjectFile *> ObjectFile::createMachOObjectFile(MemoryBuffer *Buffer,
1564                                                         bool BufferOwned) {
1565   StringRef Magic = Buffer->getBuffer().slice(0, 4);
1566   error_code EC;
1567   std::unique_ptr<MachOObjectFile> Ret;
1568   if (Magic == "\xFE\xED\xFA\xCE")
1569     Ret.reset(new MachOObjectFile(Buffer, false, false, EC, BufferOwned));
1570   else if (Magic == "\xCE\xFA\xED\xFE")
1571     Ret.reset(new MachOObjectFile(Buffer, true, false, EC, BufferOwned));
1572   else if (Magic == "\xFE\xED\xFA\xCF")
1573     Ret.reset(new MachOObjectFile(Buffer, false, true, EC, BufferOwned));
1574   else if (Magic == "\xCF\xFA\xED\xFE")
1575     Ret.reset(new MachOObjectFile(Buffer, true, true, EC, BufferOwned));
1576   else {
1577     delete Buffer;
1578     return object_error::parse_failed;
1579   }
1580 
1581   if (EC)
1582     return EC;
1583   return Ret.release();
1584 }
1585 
1586 } // end namespace object
1587 } // end namespace llvm
1588