xref: /llvm-project/llvm/lib/Object/MachOObjectFile.cpp (revision 7d602f7a77fd099bd7936dba70fba4e93b68dd5f) 
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 {
31   struct section_base {
32     char sectname[16];
33     char segname[16];
34   };
35 }
36 
37 template<typename T>
38 static T getStruct(const MachOObjectFile *O, const char *P) {
39   T Cmd;
40   memcpy(&Cmd, P, sizeof(T));
41   if (O->isLittleEndian() != sys::IsLittleEndianHost)
42     MachO::swapStruct(Cmd);
43   return Cmd;
44 }
45 
46 static uint32_t
47 getSegmentLoadCommandNumSections(const MachOObjectFile *O,
48                                  const MachOObjectFile::LoadCommandInfo &L) {
49   if (O->is64Bit()) {
50     MachO::segment_command_64 S = O->getSegment64LoadCommand(L);
51     return S.nsects;
52   }
53   MachO::segment_command S = O->getSegmentLoadCommand(L);
54   return S.nsects;
55 }
56 
57 static const char *
58 getSectionPtr(const MachOObjectFile *O, MachOObjectFile::LoadCommandInfo L,
59               unsigned Sec) {
60   uintptr_t CommandAddr = reinterpret_cast<uintptr_t>(L.Ptr);
61 
62   bool Is64 = O->is64Bit();
63   unsigned SegmentLoadSize = Is64 ? sizeof(MachO::segment_command_64) :
64                                     sizeof(MachO::segment_command);
65   unsigned SectionSize = Is64 ? sizeof(MachO::section_64) :
66                                 sizeof(MachO::section);
67 
68   uintptr_t SectionAddr = CommandAddr + SegmentLoadSize + Sec * SectionSize;
69   return reinterpret_cast<const char*>(SectionAddr);
70 }
71 
72 static const char *getPtr(const MachOObjectFile *O, size_t Offset) {
73   return O->getData().substr(Offset, 1).data();
74 }
75 
76 static MachO::nlist_base
77 getSymbolTableEntryBase(const MachOObjectFile *O, DataRefImpl DRI) {
78   const char *P = reinterpret_cast<const char *>(DRI.p);
79   return getStruct<MachO::nlist_base>(O, P);
80 }
81 
82 static StringRef parseSegmentOrSectionName(const char *P) {
83   if (P[15] == 0)
84     // Null terminated.
85     return P;
86   // Not null terminated, so this is a 16 char string.
87   return StringRef(P, 16);
88 }
89 
90 // Helper to advance a section or symbol iterator multiple increments at a time.
91 template<class T>
92 static void advance(T &it, size_t Val) {
93   while (Val--)
94     ++it;
95 }
96 
97 static unsigned getCPUType(const MachOObjectFile *O) {
98   return O->getHeader().cputype;
99 }
100 
101 static void printRelocationTargetName(const MachOObjectFile *O,
102                                       const MachO::any_relocation_info &RE,
103                                       raw_string_ostream &fmt) {
104   bool IsScattered = O->isRelocationScattered(RE);
105 
106   // Target of a scattered relocation is an address.  In the interest of
107   // generating pretty output, scan through the symbol table looking for a
108   // symbol that aligns with that address.  If we find one, print it.
109   // Otherwise, we just print the hex address of the target.
110   if (IsScattered) {
111     uint32_t Val = O->getPlainRelocationSymbolNum(RE);
112 
113     for (const SymbolRef &Symbol : O->symbols()) {
114       std::error_code ec;
115       uint64_t Addr;
116       StringRef Name;
117 
118       if ((ec = Symbol.getAddress(Addr)))
119         report_fatal_error(ec.message());
120       if (Addr != Val)
121         continue;
122       if ((ec = Symbol.getName(Name)))
123         report_fatal_error(ec.message());
124       fmt << Name;
125       return;
126     }
127 
128     // If we couldn't find a symbol that this relocation refers to, try
129     // to find a section beginning instead.
130     for (const SectionRef &Section : O->sections()) {
131       std::error_code ec;
132       uint64_t Addr;
133       StringRef Name;
134 
135       if ((ec = Section.getAddress(Addr)))
136         report_fatal_error(ec.message());
137       if (Addr != Val)
138         continue;
139       if ((ec = Section.getName(Name)))
140         report_fatal_error(ec.message());
141       fmt << Name;
142       return;
143     }
144 
145     fmt << format("0x%x", Val);
146     return;
147   }
148 
149   StringRef S;
150   bool isExtern = O->getPlainRelocationExternal(RE);
151   uint64_t Val = O->getPlainRelocationSymbolNum(RE);
152 
153   if (isExtern) {
154     symbol_iterator SI = O->symbol_begin();
155     advance(SI, Val);
156     SI->getName(S);
157   } else {
158     section_iterator SI = O->section_begin();
159     // Adjust for the fact that sections are 1-indexed.
160     advance(SI, Val - 1);
161     SI->getName(S);
162   }
163 
164   fmt << S;
165 }
166 
167 static uint32_t
168 getPlainRelocationAddress(const MachO::any_relocation_info &RE) {
169   return RE.r_word0;
170 }
171 
172 static unsigned
173 getScatteredRelocationAddress(const MachO::any_relocation_info &RE) {
174   return RE.r_word0 & 0xffffff;
175 }
176 
177 static bool getPlainRelocationPCRel(const MachOObjectFile *O,
178                                     const MachO::any_relocation_info &RE) {
179   if (O->isLittleEndian())
180     return (RE.r_word1 >> 24) & 1;
181   return (RE.r_word1 >> 7) & 1;
182 }
183 
184 static bool
185 getScatteredRelocationPCRel(const MachOObjectFile *O,
186                             const MachO::any_relocation_info &RE) {
187   return (RE.r_word0 >> 30) & 1;
188 }
189 
190 static unsigned getPlainRelocationLength(const MachOObjectFile *O,
191                                          const MachO::any_relocation_info &RE) {
192   if (O->isLittleEndian())
193     return (RE.r_word1 >> 25) & 3;
194   return (RE.r_word1 >> 5) & 3;
195 }
196 
197 static unsigned
198 getScatteredRelocationLength(const MachO::any_relocation_info &RE) {
199   return (RE.r_word0 >> 28) & 3;
200 }
201 
202 static unsigned getPlainRelocationType(const MachOObjectFile *O,
203                                        const MachO::any_relocation_info &RE) {
204   if (O->isLittleEndian())
205     return RE.r_word1 >> 28;
206   return RE.r_word1 & 0xf;
207 }
208 
209 static unsigned
210 getScatteredRelocationType(const MachO::any_relocation_info &RE) {
211   return (RE.r_word0 >> 24) & 0xf;
212 }
213 
214 static uint32_t getSectionFlags(const MachOObjectFile *O,
215                                 DataRefImpl Sec) {
216   if (O->is64Bit()) {
217     MachO::section_64 Sect = O->getSection64(Sec);
218     return Sect.flags;
219   }
220   MachO::section Sect = O->getSection(Sec);
221   return Sect.flags;
222 }
223 
224 MachOObjectFile::MachOObjectFile(std::unique_ptr<MemoryBuffer> Object,
225                                  bool IsLittleEndian, bool Is64bits,
226                                  std::error_code &EC)
227     : ObjectFile(getMachOType(IsLittleEndian, Is64bits), std::move(Object)),
228       SymtabLoadCmd(nullptr), DysymtabLoadCmd(nullptr),
229       DataInCodeLoadCmd(nullptr) {
230   uint32_t LoadCommandCount = this->getHeader().ncmds;
231   MachO::LoadCommandType SegmentLoadType = is64Bit() ?
232     MachO::LC_SEGMENT_64 : MachO::LC_SEGMENT;
233 
234   MachOObjectFile::LoadCommandInfo Load = getFirstLoadCommandInfo();
235   for (unsigned I = 0; ; ++I) {
236     if (Load.C.cmd == MachO::LC_SYMTAB) {
237       assert(!SymtabLoadCmd && "Multiple symbol tables");
238       SymtabLoadCmd = Load.Ptr;
239     } else if (Load.C.cmd == MachO::LC_DYSYMTAB) {
240       assert(!DysymtabLoadCmd && "Multiple dynamic symbol tables");
241       DysymtabLoadCmd = Load.Ptr;
242     } else if (Load.C.cmd == MachO::LC_DATA_IN_CODE) {
243       assert(!DataInCodeLoadCmd && "Multiple data in code tables");
244       DataInCodeLoadCmd = Load.Ptr;
245     } else if (Load.C.cmd == SegmentLoadType) {
246       uint32_t NumSections = getSegmentLoadCommandNumSections(this, Load);
247       for (unsigned J = 0; J < NumSections; ++J) {
248         const char *Sec = getSectionPtr(this, Load, J);
249         Sections.push_back(Sec);
250       }
251     } else if (Load.C.cmd == MachO::LC_LOAD_DYLIB ||
252                Load.C.cmd == MachO::LC_LOAD_WEAK_DYLIB ||
253                Load.C.cmd == MachO::LC_LAZY_LOAD_DYLIB ||
254                Load.C.cmd == MachO::LC_REEXPORT_DYLIB ||
255                Load.C.cmd == MachO::LC_LOAD_UPWARD_DYLIB) {
256       Libraries.push_back(Load.Ptr);
257     }
258 
259     if (I == LoadCommandCount - 1)
260       break;
261     else
262       Load = getNextLoadCommandInfo(Load);
263   }
264 }
265 
266 void MachOObjectFile::moveSymbolNext(DataRefImpl &Symb) const {
267   unsigned SymbolTableEntrySize = is64Bit() ?
268     sizeof(MachO::nlist_64) :
269     sizeof(MachO::nlist);
270   Symb.p += SymbolTableEntrySize;
271 }
272 
273 std::error_code MachOObjectFile::getSymbolName(DataRefImpl Symb,
274                                                StringRef &Res) const {
275   StringRef StringTable = getStringTableData();
276   MachO::nlist_base Entry = getSymbolTableEntryBase(this, Symb);
277   const char *Start = &StringTable.data()[Entry.n_strx];
278   Res = StringRef(Start);
279   return object_error::success;
280 }
281 
282 // getIndirectName() returns the name of the alias'ed symbol who's string table
283 // index is in the n_value field.
284 std::error_code MachOObjectFile::getIndirectName(DataRefImpl Symb,
285                                                  StringRef &Res) const {
286   StringRef StringTable = getStringTableData();
287   uint64_t NValue;
288   if (is64Bit()) {
289     MachO::nlist_64 Entry = getSymbol64TableEntry(Symb);
290     NValue = Entry.n_value;
291     if ((Entry.n_type & MachO::N_TYPE) != MachO::N_INDR)
292       return object_error::parse_failed;
293   } else {
294     MachO::nlist Entry = getSymbolTableEntry(Symb);
295     NValue = Entry.n_value;
296     if ((Entry.n_type & MachO::N_TYPE) != MachO::N_INDR)
297       return object_error::parse_failed;
298   }
299   if (NValue >= StringTable.size())
300     return object_error::parse_failed;
301   const char *Start = &StringTable.data()[NValue];
302   Res = StringRef(Start);
303   return object_error::success;
304 }
305 
306 std::error_code MachOObjectFile::getSymbolAddress(DataRefImpl Symb,
307                                                   uint64_t &Res) const {
308   if (is64Bit()) {
309     MachO::nlist_64 Entry = getSymbol64TableEntry(Symb);
310     if ((Entry.n_type & MachO::N_TYPE) == MachO::N_UNDF &&
311         Entry.n_value == 0)
312       Res = UnknownAddressOrSize;
313     else
314       Res = Entry.n_value;
315   } else {
316     MachO::nlist Entry = getSymbolTableEntry(Symb);
317     if ((Entry.n_type & MachO::N_TYPE) == MachO::N_UNDF &&
318         Entry.n_value == 0)
319       Res = UnknownAddressOrSize;
320     else
321       Res = Entry.n_value;
322   }
323   return object_error::success;
324 }
325 
326 std::error_code MachOObjectFile::getSymbolAlignment(DataRefImpl DRI,
327                                                     uint32_t &Result) const {
328   uint32_t flags = getSymbolFlags(DRI);
329   if (flags & SymbolRef::SF_Common) {
330     MachO::nlist_base Entry = getSymbolTableEntryBase(this, DRI);
331     Result = 1 << MachO::GET_COMM_ALIGN(Entry.n_desc);
332   } else {
333     Result = 0;
334   }
335   return object_error::success;
336 }
337 
338 std::error_code MachOObjectFile::getSymbolSize(DataRefImpl DRI,
339                                                uint64_t &Result) const {
340   uint64_t BeginOffset;
341   uint64_t EndOffset = 0;
342   uint8_t SectionIndex;
343 
344   MachO::nlist_base Entry = getSymbolTableEntryBase(this, DRI);
345   uint64_t Value;
346   getSymbolAddress(DRI, Value);
347   if (Value == UnknownAddressOrSize) {
348     Result = UnknownAddressOrSize;
349     return object_error::success;
350   }
351 
352   BeginOffset = Value;
353 
354   SectionIndex = Entry.n_sect;
355   if (!SectionIndex) {
356     uint32_t flags = getSymbolFlags(DRI);
357     if (flags & SymbolRef::SF_Common)
358       Result = Value;
359     else
360       Result = UnknownAddressOrSize;
361     return object_error::success;
362   }
363   // Unfortunately symbols are unsorted so we need to touch all
364   // symbols from load command
365   for (const SymbolRef &Symbol : symbols()) {
366     DataRefImpl DRI = Symbol.getRawDataRefImpl();
367     Entry = getSymbolTableEntryBase(this, DRI);
368     getSymbolAddress(DRI, Value);
369     if (Value == UnknownAddressOrSize)
370       continue;
371     if (Entry.n_sect == SectionIndex && Value > BeginOffset)
372       if (!EndOffset || Value < EndOffset)
373         EndOffset = Value;
374   }
375   if (!EndOffset) {
376     uint64_t Size;
377     DataRefImpl Sec;
378     Sec.d.a = SectionIndex-1;
379     getSectionSize(Sec, Size);
380     getSectionAddress(Sec, EndOffset);
381     EndOffset += Size;
382   }
383   Result = EndOffset - BeginOffset;
384   return object_error::success;
385 }
386 
387 std::error_code MachOObjectFile::getSymbolType(DataRefImpl Symb,
388                                                SymbolRef::Type &Res) const {
389   MachO::nlist_base Entry = getSymbolTableEntryBase(this, Symb);
390   uint8_t n_type = Entry.n_type;
391 
392   Res = SymbolRef::ST_Other;
393 
394   // If this is a STAB debugging symbol, we can do nothing more.
395   if (n_type & MachO::N_STAB) {
396     Res = SymbolRef::ST_Debug;
397     return object_error::success;
398   }
399 
400   switch (n_type & MachO::N_TYPE) {
401     case MachO::N_UNDF :
402       Res = SymbolRef::ST_Unknown;
403       break;
404     case MachO::N_SECT :
405       Res = SymbolRef::ST_Function;
406       break;
407   }
408   return object_error::success;
409 }
410 
411 uint32_t MachOObjectFile::getSymbolFlags(DataRefImpl DRI) const {
412   MachO::nlist_base Entry = getSymbolTableEntryBase(this, DRI);
413 
414   uint8_t MachOType = Entry.n_type;
415   uint16_t MachOFlags = Entry.n_desc;
416 
417   uint32_t Result = SymbolRef::SF_None;
418 
419   if ((MachOType & MachO::N_TYPE) == MachO::N_UNDF)
420     Result |= SymbolRef::SF_Undefined;
421 
422   if ((MachOType & MachO::N_TYPE) == MachO::N_INDR)
423     Result |= SymbolRef::SF_Indirect;
424 
425   if (MachOType & MachO::N_STAB)
426     Result |= SymbolRef::SF_FormatSpecific;
427 
428   if (MachOType & MachO::N_EXT) {
429     Result |= SymbolRef::SF_Global;
430     if ((MachOType & MachO::N_TYPE) == MachO::N_UNDF) {
431       uint64_t Value;
432       getSymbolAddress(DRI, Value);
433       if (Value && Value != UnknownAddressOrSize)
434         Result |= SymbolRef::SF_Common;
435     }
436   }
437 
438   if (MachOFlags & (MachO::N_WEAK_REF | MachO::N_WEAK_DEF))
439     Result |= SymbolRef::SF_Weak;
440 
441   if ((MachOType & MachO::N_TYPE) == MachO::N_ABS)
442     Result |= SymbolRef::SF_Absolute;
443 
444   return Result;
445 }
446 
447 std::error_code MachOObjectFile::getSymbolSection(DataRefImpl Symb,
448                                                   section_iterator &Res) const {
449   MachO::nlist_base Entry = getSymbolTableEntryBase(this, Symb);
450   uint8_t index = Entry.n_sect;
451 
452   if (index == 0) {
453     Res = section_end();
454   } else {
455     DataRefImpl DRI;
456     DRI.d.a = index - 1;
457     Res = section_iterator(SectionRef(DRI, this));
458   }
459 
460   return object_error::success;
461 }
462 
463 void MachOObjectFile::moveSectionNext(DataRefImpl &Sec) const {
464   Sec.d.a++;
465 }
466 
467 std::error_code MachOObjectFile::getSectionName(DataRefImpl Sec,
468                                                 StringRef &Result) const {
469   ArrayRef<char> Raw = getSectionRawName(Sec);
470   Result = parseSegmentOrSectionName(Raw.data());
471   return object_error::success;
472 }
473 
474 std::error_code MachOObjectFile::getSectionAddress(DataRefImpl Sec,
475                                                    uint64_t &Res) const {
476   if (is64Bit()) {
477     MachO::section_64 Sect = getSection64(Sec);
478     Res = Sect.addr;
479   } else {
480     MachO::section Sect = getSection(Sec);
481     Res = Sect.addr;
482   }
483   return object_error::success;
484 }
485 
486 std::error_code MachOObjectFile::getSectionSize(DataRefImpl Sec,
487                                                 uint64_t &Res) const {
488   if (is64Bit()) {
489     MachO::section_64 Sect = getSection64(Sec);
490     Res = Sect.size;
491   } else {
492     MachO::section Sect = getSection(Sec);
493     Res = Sect.size;
494   }
495 
496   return object_error::success;
497 }
498 
499 std::error_code MachOObjectFile::getSectionContents(DataRefImpl Sec,
500                                                     StringRef &Res) const {
501   uint32_t Offset;
502   uint64_t Size;
503 
504   if (is64Bit()) {
505     MachO::section_64 Sect = getSection64(Sec);
506     Offset = Sect.offset;
507     Size = Sect.size;
508   } else {
509     MachO::section Sect = getSection(Sec);
510     Offset = Sect.offset;
511     Size = Sect.size;
512   }
513 
514   Res = this->getData().substr(Offset, Size);
515   return object_error::success;
516 }
517 
518 std::error_code MachOObjectFile::getSectionAlignment(DataRefImpl Sec,
519                                                      uint64_t &Res) const {
520   uint32_t Align;
521   if (is64Bit()) {
522     MachO::section_64 Sect = getSection64(Sec);
523     Align = Sect.align;
524   } else {
525     MachO::section Sect = getSection(Sec);
526     Align = Sect.align;
527   }
528 
529   Res = uint64_t(1) << Align;
530   return object_error::success;
531 }
532 
533 std::error_code MachOObjectFile::isSectionText(DataRefImpl Sec,
534                                                bool &Res) const {
535   uint32_t Flags = getSectionFlags(this, Sec);
536   Res = Flags & MachO::S_ATTR_PURE_INSTRUCTIONS;
537   return object_error::success;
538 }
539 
540 std::error_code MachOObjectFile::isSectionData(DataRefImpl Sec,
541                                                bool &Result) const {
542   uint32_t Flags = getSectionFlags(this, Sec);
543   unsigned SectionType = Flags & MachO::SECTION_TYPE;
544   Result = !(Flags & MachO::S_ATTR_PURE_INSTRUCTIONS) &&
545            !(SectionType == MachO::S_ZEROFILL ||
546              SectionType == MachO::S_GB_ZEROFILL);
547   return object_error::success;
548 }
549 
550 std::error_code MachOObjectFile::isSectionBSS(DataRefImpl Sec,
551                                               bool &Result) const {
552   uint32_t Flags = getSectionFlags(this, Sec);
553   unsigned SectionType = Flags & MachO::SECTION_TYPE;
554   Result = !(Flags & MachO::S_ATTR_PURE_INSTRUCTIONS) &&
555            (SectionType == MachO::S_ZEROFILL ||
556             SectionType == MachO::S_GB_ZEROFILL);
557   return object_error::success;
558 }
559 
560 std::error_code
561 MachOObjectFile::isSectionRequiredForExecution(DataRefImpl Sec,
562                                                bool &Result) const {
563   // FIXME: Unimplemented.
564   Result = true;
565   return object_error::success;
566 }
567 
568 std::error_code MachOObjectFile::isSectionVirtual(DataRefImpl Sec,
569                                                   bool &Result) const {
570   // FIXME: Unimplemented.
571   Result = false;
572   return object_error::success;
573 }
574 
575 std::error_code MachOObjectFile::isSectionZeroInit(DataRefImpl Sec,
576                                                    bool &Res) const {
577   uint32_t Flags = getSectionFlags(this, Sec);
578   unsigned SectionType = Flags & MachO::SECTION_TYPE;
579   Res = SectionType == MachO::S_ZEROFILL ||
580     SectionType == MachO::S_GB_ZEROFILL;
581   return object_error::success;
582 }
583 
584 std::error_code MachOObjectFile::isSectionReadOnlyData(DataRefImpl Sec,
585                                                        bool &Result) const {
586   // Consider using the code from isSectionText to look for __const sections.
587   // Alternately, emit S_ATTR_PURE_INSTRUCTIONS and/or S_ATTR_SOME_INSTRUCTIONS
588   // to use section attributes to distinguish code from data.
589 
590   // FIXME: Unimplemented.
591   Result = false;
592   return object_error::success;
593 }
594 
595 std::error_code MachOObjectFile::sectionContainsSymbol(DataRefImpl Sec,
596                                                        DataRefImpl Symb,
597                                                        bool &Result) const {
598   SymbolRef::Type ST;
599   this->getSymbolType(Symb, ST);
600   if (ST == SymbolRef::ST_Unknown) {
601     Result = false;
602     return object_error::success;
603   }
604 
605   uint64_t SectBegin, SectEnd;
606   getSectionAddress(Sec, SectBegin);
607   getSectionSize(Sec, SectEnd);
608   SectEnd += SectBegin;
609 
610   uint64_t SymAddr;
611   getSymbolAddress(Symb, SymAddr);
612   Result = (SymAddr >= SectBegin) && (SymAddr < SectEnd);
613 
614   return object_error::success;
615 }
616 
617 relocation_iterator MachOObjectFile::section_rel_begin(DataRefImpl Sec) const {
618   DataRefImpl Ret;
619   Ret.d.a = Sec.d.a;
620   Ret.d.b = 0;
621   return relocation_iterator(RelocationRef(Ret, this));
622 }
623 
624 relocation_iterator
625 MachOObjectFile::section_rel_end(DataRefImpl Sec) const {
626   uint32_t Num;
627   if (is64Bit()) {
628     MachO::section_64 Sect = getSection64(Sec);
629     Num = Sect.nreloc;
630   } else {
631     MachO::section Sect = getSection(Sec);
632     Num = Sect.nreloc;
633   }
634 
635   DataRefImpl Ret;
636   Ret.d.a = Sec.d.a;
637   Ret.d.b = Num;
638   return relocation_iterator(RelocationRef(Ret, this));
639 }
640 
641 void MachOObjectFile::moveRelocationNext(DataRefImpl &Rel) const {
642   ++Rel.d.b;
643 }
644 
645 std::error_code MachOObjectFile::getRelocationAddress(DataRefImpl Rel,
646                                                       uint64_t &Res) const {
647   uint64_t Offset;
648   getRelocationOffset(Rel, Offset);
649 
650   DataRefImpl Sec;
651   Sec.d.a = Rel.d.a;
652   uint64_t SecAddress;
653   getSectionAddress(Sec, SecAddress);
654   Res = SecAddress + Offset;
655   return object_error::success;
656 }
657 
658 std::error_code MachOObjectFile::getRelocationOffset(DataRefImpl Rel,
659                                                      uint64_t &Res) const {
660   assert(getHeader().filetype == MachO::MH_OBJECT &&
661          "Only implemented for MH_OBJECT");
662   MachO::any_relocation_info RE = getRelocation(Rel);
663   Res = getAnyRelocationAddress(RE);
664   return object_error::success;
665 }
666 
667 symbol_iterator
668 MachOObjectFile::getRelocationSymbol(DataRefImpl Rel) const {
669   MachO::any_relocation_info RE = getRelocation(Rel);
670   if (isRelocationScattered(RE))
671     return symbol_end();
672 
673   uint32_t SymbolIdx = getPlainRelocationSymbolNum(RE);
674   bool isExtern = getPlainRelocationExternal(RE);
675   if (!isExtern)
676     return symbol_end();
677 
678   MachO::symtab_command S = getSymtabLoadCommand();
679   unsigned SymbolTableEntrySize = is64Bit() ?
680     sizeof(MachO::nlist_64) :
681     sizeof(MachO::nlist);
682   uint64_t Offset = S.symoff + SymbolIdx * SymbolTableEntrySize;
683   DataRefImpl Sym;
684   Sym.p = reinterpret_cast<uintptr_t>(getPtr(this, Offset));
685   return symbol_iterator(SymbolRef(Sym, this));
686 }
687 
688 std::error_code MachOObjectFile::getRelocationType(DataRefImpl Rel,
689                                                    uint64_t &Res) const {
690   MachO::any_relocation_info RE = getRelocation(Rel);
691   Res = getAnyRelocationType(RE);
692   return object_error::success;
693 }
694 
695 std::error_code
696 MachOObjectFile::getRelocationTypeName(DataRefImpl Rel,
697                                        SmallVectorImpl<char> &Result) const {
698   StringRef res;
699   uint64_t RType;
700   getRelocationType(Rel, RType);
701 
702   unsigned Arch = this->getArch();
703 
704   switch (Arch) {
705     case Triple::x86: {
706       static const char *const Table[] =  {
707         "GENERIC_RELOC_VANILLA",
708         "GENERIC_RELOC_PAIR",
709         "GENERIC_RELOC_SECTDIFF",
710         "GENERIC_RELOC_PB_LA_PTR",
711         "GENERIC_RELOC_LOCAL_SECTDIFF",
712         "GENERIC_RELOC_TLV" };
713 
714       if (RType > 5)
715         res = "Unknown";
716       else
717         res = Table[RType];
718       break;
719     }
720     case Triple::x86_64: {
721       static const char *const Table[] =  {
722         "X86_64_RELOC_UNSIGNED",
723         "X86_64_RELOC_SIGNED",
724         "X86_64_RELOC_BRANCH",
725         "X86_64_RELOC_GOT_LOAD",
726         "X86_64_RELOC_GOT",
727         "X86_64_RELOC_SUBTRACTOR",
728         "X86_64_RELOC_SIGNED_1",
729         "X86_64_RELOC_SIGNED_2",
730         "X86_64_RELOC_SIGNED_4",
731         "X86_64_RELOC_TLV" };
732 
733       if (RType > 9)
734         res = "Unknown";
735       else
736         res = Table[RType];
737       break;
738     }
739     case Triple::arm: {
740       static const char *const Table[] =  {
741         "ARM_RELOC_VANILLA",
742         "ARM_RELOC_PAIR",
743         "ARM_RELOC_SECTDIFF",
744         "ARM_RELOC_LOCAL_SECTDIFF",
745         "ARM_RELOC_PB_LA_PTR",
746         "ARM_RELOC_BR24",
747         "ARM_THUMB_RELOC_BR22",
748         "ARM_THUMB_32BIT_BRANCH",
749         "ARM_RELOC_HALF",
750         "ARM_RELOC_HALF_SECTDIFF" };
751 
752       if (RType > 9)
753         res = "Unknown";
754       else
755         res = Table[RType];
756       break;
757     }
758     case Triple::arm64:
759     case Triple::aarch64: {
760       static const char *const Table[] = {
761         "ARM64_RELOC_UNSIGNED",           "ARM64_RELOC_SUBTRACTOR",
762         "ARM64_RELOC_BRANCH26",           "ARM64_RELOC_PAGE21",
763         "ARM64_RELOC_PAGEOFF12",          "ARM64_RELOC_GOT_LOAD_PAGE21",
764         "ARM64_RELOC_GOT_LOAD_PAGEOFF12", "ARM64_RELOC_POINTER_TO_GOT",
765         "ARM64_RELOC_TLVP_LOAD_PAGE21",   "ARM64_RELOC_TLVP_LOAD_PAGEOFF12",
766         "ARM64_RELOC_ADDEND"
767       };
768 
769       if (RType >= array_lengthof(Table))
770         res = "Unknown";
771       else
772         res = Table[RType];
773       break;
774     }
775     case Triple::ppc: {
776       static const char *const Table[] =  {
777         "PPC_RELOC_VANILLA",
778         "PPC_RELOC_PAIR",
779         "PPC_RELOC_BR14",
780         "PPC_RELOC_BR24",
781         "PPC_RELOC_HI16",
782         "PPC_RELOC_LO16",
783         "PPC_RELOC_HA16",
784         "PPC_RELOC_LO14",
785         "PPC_RELOC_SECTDIFF",
786         "PPC_RELOC_PB_LA_PTR",
787         "PPC_RELOC_HI16_SECTDIFF",
788         "PPC_RELOC_LO16_SECTDIFF",
789         "PPC_RELOC_HA16_SECTDIFF",
790         "PPC_RELOC_JBSR",
791         "PPC_RELOC_LO14_SECTDIFF",
792         "PPC_RELOC_LOCAL_SECTDIFF" };
793 
794       if (RType > 15)
795         res = "Unknown";
796       else
797         res = Table[RType];
798       break;
799     }
800     case Triple::UnknownArch:
801       res = "Unknown";
802       break;
803   }
804   Result.append(res.begin(), res.end());
805   return object_error::success;
806 }
807 
808 std::error_code
809 MachOObjectFile::getRelocationValueString(DataRefImpl Rel,
810                                           SmallVectorImpl<char> &Result) const {
811   MachO::any_relocation_info RE = getRelocation(Rel);
812 
813   unsigned Arch = this->getArch();
814 
815   std::string fmtbuf;
816   raw_string_ostream fmt(fmtbuf);
817   unsigned Type = this->getAnyRelocationType(RE);
818   bool IsPCRel = this->getAnyRelocationPCRel(RE);
819 
820   // Determine any addends that should be displayed with the relocation.
821   // These require decoding the relocation type, which is triple-specific.
822 
823   // X86_64 has entirely custom relocation types.
824   if (Arch == Triple::x86_64) {
825     bool isPCRel = getAnyRelocationPCRel(RE);
826 
827     switch (Type) {
828       case MachO::X86_64_RELOC_GOT_LOAD:
829       case MachO::X86_64_RELOC_GOT: {
830         printRelocationTargetName(this, RE, fmt);
831         fmt << "@GOT";
832         if (isPCRel) fmt << "PCREL";
833         break;
834       }
835       case MachO::X86_64_RELOC_SUBTRACTOR: {
836         DataRefImpl RelNext = Rel;
837         moveRelocationNext(RelNext);
838         MachO::any_relocation_info RENext = getRelocation(RelNext);
839 
840         // X86_64_RELOC_SUBTRACTOR must be followed by a relocation of type
841         // X86_64_RELOC_UNSIGNED.
842         // NOTE: Scattered relocations don't exist on x86_64.
843         unsigned RType = getAnyRelocationType(RENext);
844         if (RType != MachO::X86_64_RELOC_UNSIGNED)
845           report_fatal_error("Expected X86_64_RELOC_UNSIGNED after "
846                              "X86_64_RELOC_SUBTRACTOR.");
847 
848         // The X86_64_RELOC_UNSIGNED contains the minuend symbol;
849         // X86_64_RELOC_SUBTRACTOR contains the subtrahend.
850         printRelocationTargetName(this, RENext, fmt);
851         fmt << "-";
852         printRelocationTargetName(this, RE, fmt);
853         break;
854       }
855       case MachO::X86_64_RELOC_TLV:
856         printRelocationTargetName(this, RE, fmt);
857         fmt << "@TLV";
858         if (isPCRel) fmt << "P";
859         break;
860       case MachO::X86_64_RELOC_SIGNED_1:
861         printRelocationTargetName(this, RE, fmt);
862         fmt << "-1";
863         break;
864       case MachO::X86_64_RELOC_SIGNED_2:
865         printRelocationTargetName(this, RE, fmt);
866         fmt << "-2";
867         break;
868       case MachO::X86_64_RELOC_SIGNED_4:
869         printRelocationTargetName(this, RE, fmt);
870         fmt << "-4";
871         break;
872       default:
873         printRelocationTargetName(this, RE, fmt);
874         break;
875     }
876   // X86 and ARM share some relocation types in common.
877   } else if (Arch == Triple::x86 || Arch == Triple::arm ||
878              Arch == Triple::ppc) {
879     // Generic relocation types...
880     switch (Type) {
881       case MachO::GENERIC_RELOC_PAIR: // prints no info
882         return object_error::success;
883       case MachO::GENERIC_RELOC_SECTDIFF: {
884         DataRefImpl RelNext = Rel;
885         moveRelocationNext(RelNext);
886         MachO::any_relocation_info RENext = getRelocation(RelNext);
887 
888         // X86 sect diff's must be followed by a relocation of type
889         // GENERIC_RELOC_PAIR.
890         unsigned RType = getAnyRelocationType(RENext);
891 
892         if (RType != MachO::GENERIC_RELOC_PAIR)
893           report_fatal_error("Expected GENERIC_RELOC_PAIR after "
894                              "GENERIC_RELOC_SECTDIFF.");
895 
896         printRelocationTargetName(this, RE, fmt);
897         fmt << "-";
898         printRelocationTargetName(this, RENext, fmt);
899         break;
900       }
901     }
902 
903     if (Arch == Triple::x86 || Arch == Triple::ppc) {
904       switch (Type) {
905         case MachO::GENERIC_RELOC_LOCAL_SECTDIFF: {
906           DataRefImpl RelNext = Rel;
907           moveRelocationNext(RelNext);
908           MachO::any_relocation_info RENext = getRelocation(RelNext);
909 
910           // X86 sect diff's must be followed by a relocation of type
911           // GENERIC_RELOC_PAIR.
912           unsigned RType = getAnyRelocationType(RENext);
913           if (RType != MachO::GENERIC_RELOC_PAIR)
914             report_fatal_error("Expected GENERIC_RELOC_PAIR after "
915                                "GENERIC_RELOC_LOCAL_SECTDIFF.");
916 
917           printRelocationTargetName(this, RE, fmt);
918           fmt << "-";
919           printRelocationTargetName(this, RENext, fmt);
920           break;
921         }
922         case MachO::GENERIC_RELOC_TLV: {
923           printRelocationTargetName(this, RE, fmt);
924           fmt << "@TLV";
925           if (IsPCRel) fmt << "P";
926           break;
927         }
928         default:
929           printRelocationTargetName(this, RE, fmt);
930       }
931     } else { // ARM-specific relocations
932       switch (Type) {
933         case MachO::ARM_RELOC_HALF:
934         case MachO::ARM_RELOC_HALF_SECTDIFF: {
935           // Half relocations steal a bit from the length field to encode
936           // whether this is an upper16 or a lower16 relocation.
937           bool isUpper = getAnyRelocationLength(RE) >> 1;
938 
939           if (isUpper)
940             fmt << ":upper16:(";
941           else
942             fmt << ":lower16:(";
943           printRelocationTargetName(this, RE, fmt);
944 
945           DataRefImpl RelNext = Rel;
946           moveRelocationNext(RelNext);
947           MachO::any_relocation_info RENext = getRelocation(RelNext);
948 
949           // ARM half relocs must be followed by a relocation of type
950           // ARM_RELOC_PAIR.
951           unsigned RType = getAnyRelocationType(RENext);
952           if (RType != MachO::ARM_RELOC_PAIR)
953             report_fatal_error("Expected ARM_RELOC_PAIR after "
954                                "ARM_RELOC_HALF");
955 
956           // NOTE: The half of the target virtual address is stashed in the
957           // address field of the secondary relocation, but we can't reverse
958           // engineer the constant offset from it without decoding the movw/movt
959           // instruction to find the other half in its immediate field.
960 
961           // ARM_RELOC_HALF_SECTDIFF encodes the second section in the
962           // symbol/section pointer of the follow-on relocation.
963           if (Type == MachO::ARM_RELOC_HALF_SECTDIFF) {
964             fmt << "-";
965             printRelocationTargetName(this, RENext, fmt);
966           }
967 
968           fmt << ")";
969           break;
970         }
971         default: {
972           printRelocationTargetName(this, RE, fmt);
973         }
974       }
975     }
976   } else
977     printRelocationTargetName(this, RE, fmt);
978 
979   fmt.flush();
980   Result.append(fmtbuf.begin(), fmtbuf.end());
981   return object_error::success;
982 }
983 
984 std::error_code MachOObjectFile::getRelocationHidden(DataRefImpl Rel,
985                                                      bool &Result) const {
986   unsigned Arch = getArch();
987   uint64_t Type;
988   getRelocationType(Rel, Type);
989 
990   Result = false;
991 
992   // On arches that use the generic relocations, GENERIC_RELOC_PAIR
993   // is always hidden.
994   if (Arch == Triple::x86 || Arch == Triple::arm || Arch == Triple::ppc) {
995     if (Type == MachO::GENERIC_RELOC_PAIR) Result = true;
996   } else if (Arch == Triple::x86_64) {
997     // On x86_64, X86_64_RELOC_UNSIGNED is hidden only when it follows
998     // an X86_64_RELOC_SUBTRACTOR.
999     if (Type == MachO::X86_64_RELOC_UNSIGNED && Rel.d.a > 0) {
1000       DataRefImpl RelPrev = Rel;
1001       RelPrev.d.a--;
1002       uint64_t PrevType;
1003       getRelocationType(RelPrev, PrevType);
1004       if (PrevType == MachO::X86_64_RELOC_SUBTRACTOR)
1005         Result = true;
1006     }
1007   }
1008 
1009   return object_error::success;
1010 }
1011 
1012 std::error_code MachOObjectFile::getLibraryNext(DataRefImpl LibData,
1013                                                 LibraryRef &Res) const {
1014   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1015 }
1016 
1017 std::error_code MachOObjectFile::getLibraryPath(DataRefImpl LibData,
1018                                                 StringRef &Res) const {
1019   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1020 }
1021 
1022 //
1023 // guessLibraryShortName() is passed a name of a dynamic library and returns a
1024 // guess on what the short name is.  Then name is returned as a substring of the
1025 // StringRef Name passed in.  The name of the dynamic library is recognized as
1026 // a framework if it has one of the two following forms:
1027 //      Foo.framework/Versions/A/Foo
1028 //      Foo.framework/Foo
1029 // Where A and Foo can be any string.  And may contain a trailing suffix
1030 // starting with an underbar.  If the Name is recognized as a framework then
1031 // isFramework is set to true else it is set to false.  If the Name has a
1032 // suffix then Suffix is set to the substring in Name that contains the suffix
1033 // else it is set to a NULL StringRef.
1034 //
1035 // The Name of the dynamic library is recognized as a library name if it has
1036 // one of the two following forms:
1037 //      libFoo.A.dylib
1038 //      libFoo.dylib
1039 // The library may have a suffix trailing the name Foo of the form:
1040 //      libFoo_profile.A.dylib
1041 //      libFoo_profile.dylib
1042 //
1043 // The Name of the dynamic library is also recognized as a library name if it
1044 // has the following form:
1045 //      Foo.qtx
1046 //
1047 // If the Name of the dynamic library is none of the forms above then a NULL
1048 // StringRef is returned.
1049 //
1050 StringRef MachOObjectFile::guessLibraryShortName(StringRef Name,
1051                                                  bool &isFramework,
1052                                                  StringRef &Suffix) {
1053   StringRef Foo, F, DotFramework, V, Dylib, Lib, Dot, Qtx;
1054   size_t a, b, c, d, Idx;
1055 
1056   isFramework = false;
1057   Suffix = StringRef();
1058 
1059   // Pull off the last component and make Foo point to it
1060   a = Name.rfind('/');
1061   if (a == Name.npos || a == 0)
1062     goto guess_library;
1063   Foo = Name.slice(a+1, Name.npos);
1064 
1065   // Look for a suffix starting with a '_'
1066   Idx = Foo.rfind('_');
1067   if (Idx != Foo.npos && Foo.size() >= 2) {
1068     Suffix = Foo.slice(Idx, Foo.npos);
1069     Foo = Foo.slice(0, Idx);
1070   }
1071 
1072   // First look for the form Foo.framework/Foo
1073   b = Name.rfind('/', a);
1074   if (b == Name.npos)
1075     Idx = 0;
1076   else
1077     Idx = b+1;
1078   F = Name.slice(Idx, Idx + Foo.size());
1079   DotFramework = Name.slice(Idx + Foo.size(),
1080                             Idx + Foo.size() + sizeof(".framework/")-1);
1081   if (F == Foo && DotFramework == ".framework/") {
1082     isFramework = true;
1083     return Foo;
1084   }
1085 
1086   // Next look for the form Foo.framework/Versions/A/Foo
1087   if (b == Name.npos)
1088     goto guess_library;
1089   c =  Name.rfind('/', b);
1090   if (c == Name.npos || c == 0)
1091     goto guess_library;
1092   V = Name.slice(c+1, Name.npos);
1093   if (!V.startswith("Versions/"))
1094     goto guess_library;
1095   d =  Name.rfind('/', c);
1096   if (d == Name.npos)
1097     Idx = 0;
1098   else
1099     Idx = d+1;
1100   F = Name.slice(Idx, Idx + Foo.size());
1101   DotFramework = Name.slice(Idx + Foo.size(),
1102                             Idx + Foo.size() + sizeof(".framework/")-1);
1103   if (F == Foo && DotFramework == ".framework/") {
1104     isFramework = true;
1105     return Foo;
1106   }
1107 
1108 guess_library:
1109   // pull off the suffix after the "." and make a point to it
1110   a = Name.rfind('.');
1111   if (a == Name.npos || a == 0)
1112     return StringRef();
1113   Dylib = Name.slice(a, Name.npos);
1114   if (Dylib != ".dylib")
1115     goto guess_qtx;
1116 
1117   // First pull off the version letter for the form Foo.A.dylib if any.
1118   if (a >= 3) {
1119     Dot = Name.slice(a-2, a-1);
1120     if (Dot == ".")
1121       a = a - 2;
1122   }
1123 
1124   b = Name.rfind('/', a);
1125   if (b == Name.npos)
1126     b = 0;
1127   else
1128     b = b+1;
1129   // ignore any suffix after an underbar like Foo_profile.A.dylib
1130   Idx = Name.find('_', b);
1131   if (Idx != Name.npos && Idx != b) {
1132     Lib = Name.slice(b, Idx);
1133     Suffix = Name.slice(Idx, a);
1134   }
1135   else
1136     Lib = Name.slice(b, a);
1137   // There are incorrect library names of the form:
1138   // libATS.A_profile.dylib so check for these.
1139   if (Lib.size() >= 3) {
1140     Dot = Lib.slice(Lib.size()-2, Lib.size()-1);
1141     if (Dot == ".")
1142       Lib = Lib.slice(0, Lib.size()-2);
1143   }
1144   return Lib;
1145 
1146 guess_qtx:
1147   Qtx = Name.slice(a, Name.npos);
1148   if (Qtx != ".qtx")
1149     return StringRef();
1150   b = Name.rfind('/', a);
1151   if (b == Name.npos)
1152     Lib = Name.slice(0, a);
1153   else
1154     Lib = Name.slice(b+1, a);
1155   // There are library names of the form: QT.A.qtx so check for these.
1156   if (Lib.size() >= 3) {
1157     Dot = Lib.slice(Lib.size()-2, Lib.size()-1);
1158     if (Dot == ".")
1159       Lib = Lib.slice(0, Lib.size()-2);
1160   }
1161   return Lib;
1162 }
1163 
1164 // getLibraryShortNameByIndex() is used to get the short name of the library
1165 // for an undefined symbol in a linked Mach-O binary that was linked with the
1166 // normal two-level namespace default (that is MH_TWOLEVEL in the header).
1167 // It is passed the index (0 - based) of the library as translated from
1168 // GET_LIBRARY_ORDINAL (1 - based).
1169 std::error_code MachOObjectFile::getLibraryShortNameByIndex(unsigned Index,
1170                                                             StringRef &Res) {
1171   if (Index >= Libraries.size())
1172     return object_error::parse_failed;
1173 
1174   MachO::dylib_command D =
1175     getStruct<MachO::dylib_command>(this, Libraries[Index]);
1176   if (D.dylib.name >= D.cmdsize)
1177     return object_error::parse_failed;
1178 
1179   // If the cache of LibrariesShortNames is not built up do that first for
1180   // all the Libraries.
1181   if (LibrariesShortNames.size() == 0) {
1182     for (unsigned i = 0; i < Libraries.size(); i++) {
1183       MachO::dylib_command D =
1184         getStruct<MachO::dylib_command>(this, Libraries[i]);
1185       if (D.dylib.name >= D.cmdsize) {
1186         LibrariesShortNames.push_back(StringRef());
1187         continue;
1188       }
1189       const char *P = (const char *)(Libraries[i]) + D.dylib.name;
1190       StringRef Name = StringRef(P);
1191       StringRef Suffix;
1192       bool isFramework;
1193       StringRef shortName = guessLibraryShortName(Name, isFramework, Suffix);
1194       if (shortName == StringRef())
1195         LibrariesShortNames.push_back(Name);
1196       else
1197         LibrariesShortNames.push_back(shortName);
1198     }
1199   }
1200 
1201   Res = LibrariesShortNames[Index];
1202   return object_error::success;
1203 }
1204 
1205 basic_symbol_iterator MachOObjectFile::symbol_begin_impl() const {
1206   return getSymbolByIndex(0);
1207 }
1208 
1209 basic_symbol_iterator MachOObjectFile::symbol_end_impl() const {
1210   DataRefImpl DRI;
1211   if (!SymtabLoadCmd)
1212     return basic_symbol_iterator(SymbolRef(DRI, this));
1213 
1214   MachO::symtab_command Symtab = getSymtabLoadCommand();
1215   unsigned SymbolTableEntrySize = is64Bit() ?
1216     sizeof(MachO::nlist_64) :
1217     sizeof(MachO::nlist);
1218   unsigned Offset = Symtab.symoff +
1219     Symtab.nsyms * SymbolTableEntrySize;
1220   DRI.p = reinterpret_cast<uintptr_t>(getPtr(this, Offset));
1221   return basic_symbol_iterator(SymbolRef(DRI, this));
1222 }
1223 
1224 basic_symbol_iterator MachOObjectFile::getSymbolByIndex(unsigned Index) const {
1225   DataRefImpl DRI;
1226   if (!SymtabLoadCmd)
1227     return basic_symbol_iterator(SymbolRef(DRI, this));
1228 
1229   MachO::symtab_command Symtab = getSymtabLoadCommand();
1230   assert(Index < Symtab.nsyms && "Requested symbol index is out of range.");
1231   unsigned SymbolTableEntrySize =
1232     is64Bit() ? sizeof(MachO::nlist_64) : sizeof(MachO::nlist);
1233   DRI.p = reinterpret_cast<uintptr_t>(getPtr(this, Symtab.symoff));
1234   DRI.p += Index * SymbolTableEntrySize;
1235   return basic_symbol_iterator(SymbolRef(DRI, this));
1236 }
1237 
1238 section_iterator MachOObjectFile::section_begin() const {
1239   DataRefImpl DRI;
1240   return section_iterator(SectionRef(DRI, this));
1241 }
1242 
1243 section_iterator MachOObjectFile::section_end() const {
1244   DataRefImpl DRI;
1245   DRI.d.a = Sections.size();
1246   return section_iterator(SectionRef(DRI, this));
1247 }
1248 
1249 library_iterator MachOObjectFile::needed_library_begin() const {
1250   // TODO: implement
1251   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1252 }
1253 
1254 library_iterator MachOObjectFile::needed_library_end() const {
1255   // TODO: implement
1256   report_fatal_error("Needed libraries unimplemented in MachOObjectFile");
1257 }
1258 
1259 uint8_t MachOObjectFile::getBytesInAddress() const {
1260   return is64Bit() ? 8 : 4;
1261 }
1262 
1263 StringRef MachOObjectFile::getFileFormatName() const {
1264   unsigned CPUType = getCPUType(this);
1265   if (!is64Bit()) {
1266     switch (CPUType) {
1267     case llvm::MachO::CPU_TYPE_I386:
1268       return "Mach-O 32-bit i386";
1269     case llvm::MachO::CPU_TYPE_ARM:
1270       return "Mach-O arm";
1271     case llvm::MachO::CPU_TYPE_POWERPC:
1272       return "Mach-O 32-bit ppc";
1273     default:
1274       assert((CPUType & llvm::MachO::CPU_ARCH_ABI64) == 0 &&
1275              "64-bit object file when we're not 64-bit?");
1276       return "Mach-O 32-bit unknown";
1277     }
1278   }
1279 
1280   // Make sure the cpu type has the correct mask.
1281   assert((CPUType & llvm::MachO::CPU_ARCH_ABI64)
1282          == llvm::MachO::CPU_ARCH_ABI64 &&
1283          "32-bit object file when we're 64-bit?");
1284 
1285   switch (CPUType) {
1286   case llvm::MachO::CPU_TYPE_X86_64:
1287     return "Mach-O 64-bit x86-64";
1288   case llvm::MachO::CPU_TYPE_ARM64:
1289     return "Mach-O arm64";
1290   case llvm::MachO::CPU_TYPE_POWERPC64:
1291     return "Mach-O 64-bit ppc64";
1292   default:
1293     return "Mach-O 64-bit unknown";
1294   }
1295 }
1296 
1297 Triple::ArchType MachOObjectFile::getArch(uint32_t CPUType) {
1298   switch (CPUType) {
1299   case llvm::MachO::CPU_TYPE_I386:
1300     return Triple::x86;
1301   case llvm::MachO::CPU_TYPE_X86_64:
1302     return Triple::x86_64;
1303   case llvm::MachO::CPU_TYPE_ARM:
1304     return Triple::arm;
1305   case llvm::MachO::CPU_TYPE_ARM64:
1306     return Triple::arm64;
1307   case llvm::MachO::CPU_TYPE_POWERPC:
1308     return Triple::ppc;
1309   case llvm::MachO::CPU_TYPE_POWERPC64:
1310     return Triple::ppc64;
1311   default:
1312     return Triple::UnknownArch;
1313   }
1314 }
1315 
1316 Triple MachOObjectFile::getArch(uint32_t CPUType, uint32_t CPUSubType) {
1317   switch (CPUType) {
1318   case MachO::CPU_TYPE_I386:
1319     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
1320     case MachO::CPU_SUBTYPE_I386_ALL:
1321       return Triple("i386-apple-darwin");
1322     default:
1323       return Triple();
1324     }
1325   case MachO::CPU_TYPE_X86_64:
1326     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
1327     case MachO::CPU_SUBTYPE_X86_64_ALL:
1328       return Triple("x86_64-apple-darwin");
1329     case MachO::CPU_SUBTYPE_X86_64_H:
1330       return Triple("x86_64h-apple-darwin");
1331     default:
1332       return Triple();
1333     }
1334   case MachO::CPU_TYPE_ARM:
1335     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
1336     case MachO::CPU_SUBTYPE_ARM_V4T:
1337       return Triple("armv4t-apple-darwin");
1338     case MachO::CPU_SUBTYPE_ARM_V5TEJ:
1339       return Triple("armv5e-apple-darwin");
1340     case MachO::CPU_SUBTYPE_ARM_V6:
1341       return Triple("armv6-apple-darwin");
1342     case MachO::CPU_SUBTYPE_ARM_V6M:
1343       return Triple("armv6m-apple-darwin");
1344     case MachO::CPU_SUBTYPE_ARM_V7EM:
1345       return Triple("armv7em-apple-darwin");
1346     case MachO::CPU_SUBTYPE_ARM_V7K:
1347       return Triple("armv7k-apple-darwin");
1348     case MachO::CPU_SUBTYPE_ARM_V7M:
1349       return Triple("armv7m-apple-darwin");
1350     case MachO::CPU_SUBTYPE_ARM_V7S:
1351       return Triple("armv7s-apple-darwin");
1352     default:
1353       return Triple();
1354     }
1355   case MachO::CPU_TYPE_ARM64:
1356     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
1357     case MachO::CPU_SUBTYPE_ARM64_ALL:
1358       return Triple("arm64-apple-darwin");
1359     default:
1360       return Triple();
1361     }
1362   case MachO::CPU_TYPE_POWERPC:
1363     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
1364     case MachO::CPU_SUBTYPE_POWERPC_ALL:
1365       return Triple("ppc-apple-darwin");
1366     default:
1367       return Triple();
1368     }
1369   case MachO::CPU_TYPE_POWERPC64:
1370     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
1371     case MachO::CPU_SUBTYPE_POWERPC_ALL:
1372       return Triple("ppc64-apple-darwin");
1373     default:
1374       return Triple();
1375     }
1376   default:
1377     return Triple();
1378   }
1379 }
1380 
1381 Triple MachOObjectFile::getHostArch() {
1382   return Triple(sys::getDefaultTargetTriple());
1383 }
1384 
1385 Triple MachOObjectFile::getArch(StringRef ArchFlag) {
1386   if (ArchFlag == "i386")
1387     return Triple("i386-apple-darwin");
1388   else if (ArchFlag == "x86_64")
1389     return Triple("x86_64-apple-darwin");
1390   else if (ArchFlag == "x86_64h")
1391     return Triple("x86_64h-apple-darwin");
1392   else if (ArchFlag == "armv4t" || ArchFlag == "arm")
1393     return Triple("armv4t-apple-darwin");
1394   else if (ArchFlag == "armv5e")
1395     return Triple("armv5e-apple-darwin");
1396   else if (ArchFlag == "armv6")
1397     return Triple("armv6-apple-darwin");
1398   else if (ArchFlag == "armv6m")
1399     return Triple("armv6m-apple-darwin");
1400   else if (ArchFlag == "armv7em")
1401     return Triple("armv7em-apple-darwin");
1402   else if (ArchFlag == "armv7k")
1403     return Triple("armv7k-apple-darwin");
1404   else if (ArchFlag == "armv7k")
1405     return Triple("armv7m-apple-darwin");
1406   else if (ArchFlag == "armv7s")
1407     return Triple("armv7s-apple-darwin");
1408   else if (ArchFlag == "arm64")
1409     return Triple("arm64-apple-darwin");
1410   else if (ArchFlag == "ppc")
1411     return Triple("ppc-apple-darwin");
1412   else if (ArchFlag == "ppc64")
1413     return Triple("ppc64-apple-darwin");
1414   else
1415     return Triple();
1416 }
1417 
1418 unsigned MachOObjectFile::getArch() const {
1419   return getArch(getCPUType(this));
1420 }
1421 
1422 StringRef MachOObjectFile::getLoadName() const {
1423   // TODO: Implement
1424   report_fatal_error("get_load_name() unimplemented in MachOObjectFile");
1425 }
1426 
1427 relocation_iterator MachOObjectFile::section_rel_begin(unsigned Index) const {
1428   DataRefImpl DRI;
1429   DRI.d.a = Index;
1430   return section_rel_begin(DRI);
1431 }
1432 
1433 relocation_iterator MachOObjectFile::section_rel_end(unsigned Index) const {
1434   DataRefImpl DRI;
1435   DRI.d.a = Index;
1436   return section_rel_end(DRI);
1437 }
1438 
1439 dice_iterator MachOObjectFile::begin_dices() const {
1440   DataRefImpl DRI;
1441   if (!DataInCodeLoadCmd)
1442     return dice_iterator(DiceRef(DRI, this));
1443 
1444   MachO::linkedit_data_command DicLC = getDataInCodeLoadCommand();
1445   DRI.p = reinterpret_cast<uintptr_t>(getPtr(this, DicLC.dataoff));
1446   return dice_iterator(DiceRef(DRI, this));
1447 }
1448 
1449 dice_iterator MachOObjectFile::end_dices() const {
1450   DataRefImpl DRI;
1451   if (!DataInCodeLoadCmd)
1452     return dice_iterator(DiceRef(DRI, this));
1453 
1454   MachO::linkedit_data_command DicLC = getDataInCodeLoadCommand();
1455   unsigned Offset = DicLC.dataoff + DicLC.datasize;
1456   DRI.p = reinterpret_cast<uintptr_t>(getPtr(this, Offset));
1457   return dice_iterator(DiceRef(DRI, this));
1458 }
1459 
1460 StringRef
1461 MachOObjectFile::getSectionFinalSegmentName(DataRefImpl Sec) const {
1462   ArrayRef<char> Raw = getSectionRawFinalSegmentName(Sec);
1463   return parseSegmentOrSectionName(Raw.data());
1464 }
1465 
1466 ArrayRef<char>
1467 MachOObjectFile::getSectionRawName(DataRefImpl Sec) const {
1468   const section_base *Base =
1469     reinterpret_cast<const section_base *>(Sections[Sec.d.a]);
1470   return ArrayRef<char>(Base->sectname);
1471 }
1472 
1473 ArrayRef<char>
1474 MachOObjectFile::getSectionRawFinalSegmentName(DataRefImpl Sec) const {
1475   const section_base *Base =
1476     reinterpret_cast<const section_base *>(Sections[Sec.d.a]);
1477   return ArrayRef<char>(Base->segname);
1478 }
1479 
1480 bool
1481 MachOObjectFile::isRelocationScattered(const MachO::any_relocation_info &RE)
1482   const {
1483   if (getCPUType(this) == MachO::CPU_TYPE_X86_64)
1484     return false;
1485   return getPlainRelocationAddress(RE) & MachO::R_SCATTERED;
1486 }
1487 
1488 unsigned MachOObjectFile::getPlainRelocationSymbolNum(
1489     const MachO::any_relocation_info &RE) const {
1490   if (isLittleEndian())
1491     return RE.r_word1 & 0xffffff;
1492   return RE.r_word1 >> 8;
1493 }
1494 
1495 bool MachOObjectFile::getPlainRelocationExternal(
1496     const MachO::any_relocation_info &RE) const {
1497   if (isLittleEndian())
1498     return (RE.r_word1 >> 27) & 1;
1499   return (RE.r_word1 >> 4) & 1;
1500 }
1501 
1502 bool MachOObjectFile::getScatteredRelocationScattered(
1503     const MachO::any_relocation_info &RE) const {
1504   return RE.r_word0 >> 31;
1505 }
1506 
1507 uint32_t MachOObjectFile::getScatteredRelocationValue(
1508     const MachO::any_relocation_info &RE) const {
1509   return RE.r_word1;
1510 }
1511 
1512 unsigned MachOObjectFile::getAnyRelocationAddress(
1513     const MachO::any_relocation_info &RE) const {
1514   if (isRelocationScattered(RE))
1515     return getScatteredRelocationAddress(RE);
1516   return getPlainRelocationAddress(RE);
1517 }
1518 
1519 unsigned MachOObjectFile::getAnyRelocationPCRel(
1520     const MachO::any_relocation_info &RE) const {
1521   if (isRelocationScattered(RE))
1522     return getScatteredRelocationPCRel(this, RE);
1523   return getPlainRelocationPCRel(this, RE);
1524 }
1525 
1526 unsigned MachOObjectFile::getAnyRelocationLength(
1527     const MachO::any_relocation_info &RE) const {
1528   if (isRelocationScattered(RE))
1529     return getScatteredRelocationLength(RE);
1530   return getPlainRelocationLength(this, RE);
1531 }
1532 
1533 unsigned
1534 MachOObjectFile::getAnyRelocationType(
1535                                    const MachO::any_relocation_info &RE) const {
1536   if (isRelocationScattered(RE))
1537     return getScatteredRelocationType(RE);
1538   return getPlainRelocationType(this, RE);
1539 }
1540 
1541 SectionRef
1542 MachOObjectFile::getRelocationSection(
1543                                    const MachO::any_relocation_info &RE) const {
1544   if (isRelocationScattered(RE) || getPlainRelocationExternal(RE))
1545     return *section_end();
1546   unsigned SecNum = getPlainRelocationSymbolNum(RE) - 1;
1547   DataRefImpl DRI;
1548   DRI.d.a = SecNum;
1549   return SectionRef(DRI, this);
1550 }
1551 
1552 MachOObjectFile::LoadCommandInfo
1553 MachOObjectFile::getFirstLoadCommandInfo() const {
1554   MachOObjectFile::LoadCommandInfo Load;
1555 
1556   unsigned HeaderSize = is64Bit() ? sizeof(MachO::mach_header_64) :
1557                                     sizeof(MachO::mach_header);
1558   Load.Ptr = getPtr(this, HeaderSize);
1559   Load.C = getStruct<MachO::load_command>(this, Load.Ptr);
1560   return Load;
1561 }
1562 
1563 MachOObjectFile::LoadCommandInfo
1564 MachOObjectFile::getNextLoadCommandInfo(const LoadCommandInfo &L) const {
1565   MachOObjectFile::LoadCommandInfo Next;
1566   Next.Ptr = L.Ptr + L.C.cmdsize;
1567   Next.C = getStruct<MachO::load_command>(this, Next.Ptr);
1568   return Next;
1569 }
1570 
1571 MachO::section MachOObjectFile::getSection(DataRefImpl DRI) const {
1572   return getStruct<MachO::section>(this, Sections[DRI.d.a]);
1573 }
1574 
1575 MachO::section_64 MachOObjectFile::getSection64(DataRefImpl DRI) const {
1576   return getStruct<MachO::section_64>(this, Sections[DRI.d.a]);
1577 }
1578 
1579 MachO::section MachOObjectFile::getSection(const LoadCommandInfo &L,
1580                                            unsigned Index) const {
1581   const char *Sec = getSectionPtr(this, L, Index);
1582   return getStruct<MachO::section>(this, Sec);
1583 }
1584 
1585 MachO::section_64 MachOObjectFile::getSection64(const LoadCommandInfo &L,
1586                                                 unsigned Index) const {
1587   const char *Sec = getSectionPtr(this, L, Index);
1588   return getStruct<MachO::section_64>(this, Sec);
1589 }
1590 
1591 MachO::nlist
1592 MachOObjectFile::getSymbolTableEntry(DataRefImpl DRI) const {
1593   const char *P = reinterpret_cast<const char *>(DRI.p);
1594   return getStruct<MachO::nlist>(this, P);
1595 }
1596 
1597 MachO::nlist_64
1598 MachOObjectFile::getSymbol64TableEntry(DataRefImpl DRI) const {
1599   const char *P = reinterpret_cast<const char *>(DRI.p);
1600   return getStruct<MachO::nlist_64>(this, P);
1601 }
1602 
1603 MachO::linkedit_data_command
1604 MachOObjectFile::getLinkeditDataLoadCommand(const LoadCommandInfo &L) const {
1605   return getStruct<MachO::linkedit_data_command>(this, L.Ptr);
1606 }
1607 
1608 MachO::segment_command
1609 MachOObjectFile::getSegmentLoadCommand(const LoadCommandInfo &L) const {
1610   return getStruct<MachO::segment_command>(this, L.Ptr);
1611 }
1612 
1613 MachO::segment_command_64
1614 MachOObjectFile::getSegment64LoadCommand(const LoadCommandInfo &L) const {
1615   return getStruct<MachO::segment_command_64>(this, L.Ptr);
1616 }
1617 
1618 MachO::linker_options_command
1619 MachOObjectFile::getLinkerOptionsLoadCommand(const LoadCommandInfo &L) const {
1620   return getStruct<MachO::linker_options_command>(this, L.Ptr);
1621 }
1622 
1623 MachO::version_min_command
1624 MachOObjectFile::getVersionMinLoadCommand(const LoadCommandInfo &L) const {
1625   return getStruct<MachO::version_min_command>(this, L.Ptr);
1626 }
1627 
1628 MachO::dylib_command
1629 MachOObjectFile::getDylibIDLoadCommand(const LoadCommandInfo &L) const {
1630   return getStruct<MachO::dylib_command>(this, L.Ptr);
1631 }
1632 
1633 
1634 MachO::any_relocation_info
1635 MachOObjectFile::getRelocation(DataRefImpl Rel) const {
1636   DataRefImpl Sec;
1637   Sec.d.a = Rel.d.a;
1638   uint32_t Offset;
1639   if (is64Bit()) {
1640     MachO::section_64 Sect = getSection64(Sec);
1641     Offset = Sect.reloff;
1642   } else {
1643     MachO::section Sect = getSection(Sec);
1644     Offset = Sect.reloff;
1645   }
1646 
1647   auto P = reinterpret_cast<const MachO::any_relocation_info *>(
1648       getPtr(this, Offset)) + Rel.d.b;
1649   return getStruct<MachO::any_relocation_info>(
1650       this, reinterpret_cast<const char *>(P));
1651 }
1652 
1653 MachO::data_in_code_entry
1654 MachOObjectFile::getDice(DataRefImpl Rel) const {
1655   const char *P = reinterpret_cast<const char *>(Rel.p);
1656   return getStruct<MachO::data_in_code_entry>(this, P);
1657 }
1658 
1659 MachO::mach_header MachOObjectFile::getHeader() const {
1660   return getStruct<MachO::mach_header>(this, getPtr(this, 0));
1661 }
1662 
1663 MachO::mach_header_64 MachOObjectFile::getHeader64() const {
1664   return getStruct<MachO::mach_header_64>(this, getPtr(this, 0));
1665 }
1666 
1667 uint32_t MachOObjectFile::getIndirectSymbolTableEntry(
1668                                              const MachO::dysymtab_command &DLC,
1669                                              unsigned Index) const {
1670   uint64_t Offset = DLC.indirectsymoff + Index * sizeof(uint32_t);
1671   return getStruct<uint32_t>(this, getPtr(this, Offset));
1672 }
1673 
1674 MachO::data_in_code_entry
1675 MachOObjectFile::getDataInCodeTableEntry(uint32_t DataOffset,
1676                                          unsigned Index) const {
1677   uint64_t Offset = DataOffset + Index * sizeof(MachO::data_in_code_entry);
1678   return getStruct<MachO::data_in_code_entry>(this, getPtr(this, Offset));
1679 }
1680 
1681 MachO::symtab_command MachOObjectFile::getSymtabLoadCommand() const {
1682   return getStruct<MachO::symtab_command>(this, SymtabLoadCmd);
1683 }
1684 
1685 MachO::dysymtab_command MachOObjectFile::getDysymtabLoadCommand() const {
1686   return getStruct<MachO::dysymtab_command>(this, DysymtabLoadCmd);
1687 }
1688 
1689 MachO::linkedit_data_command
1690 MachOObjectFile::getDataInCodeLoadCommand() const {
1691   if (DataInCodeLoadCmd)
1692     return getStruct<MachO::linkedit_data_command>(this, DataInCodeLoadCmd);
1693 
1694   // If there is no DataInCodeLoadCmd return a load command with zero'ed fields.
1695   MachO::linkedit_data_command Cmd;
1696   Cmd.cmd = MachO::LC_DATA_IN_CODE;
1697   Cmd.cmdsize = sizeof(MachO::linkedit_data_command);
1698   Cmd.dataoff = 0;
1699   Cmd.datasize = 0;
1700   return Cmd;
1701 }
1702 
1703 StringRef MachOObjectFile::getStringTableData() const {
1704   MachO::symtab_command S = getSymtabLoadCommand();
1705   return getData().substr(S.stroff, S.strsize);
1706 }
1707 
1708 bool MachOObjectFile::is64Bit() const {
1709   return getType() == getMachOType(false, true) ||
1710     getType() == getMachOType(true, true);
1711 }
1712 
1713 void MachOObjectFile::ReadULEB128s(uint64_t Index,
1714                                    SmallVectorImpl<uint64_t> &Out) const {
1715   DataExtractor extractor(ObjectFile::getData(), true, 0);
1716 
1717   uint32_t offset = Index;
1718   uint64_t data = 0;
1719   while (uint64_t delta = extractor.getULEB128(&offset)) {
1720     data += delta;
1721     Out.push_back(data);
1722   }
1723 }
1724 
1725 ErrorOr<ObjectFile *>
1726 ObjectFile::createMachOObjectFile(std::unique_ptr<MemoryBuffer> &Buffer) {
1727   StringRef Magic = Buffer->getBuffer().slice(0, 4);
1728   std::error_code EC;
1729   std::unique_ptr<MachOObjectFile> Ret;
1730   if (Magic == "\xFE\xED\xFA\xCE")
1731     Ret.reset(new MachOObjectFile(std::move(Buffer), false, false, EC));
1732   else if (Magic == "\xCE\xFA\xED\xFE")
1733     Ret.reset(new MachOObjectFile(std::move(Buffer), true, false, EC));
1734   else if (Magic == "\xFE\xED\xFA\xCF")
1735     Ret.reset(new MachOObjectFile(std::move(Buffer), false, true, EC));
1736   else if (Magic == "\xCF\xFA\xED\xFE")
1737     Ret.reset(new MachOObjectFile(std::move(Buffer), true, true, EC));
1738   else
1739     return object_error::parse_failed;
1740 
1741   if (EC)
1742     return EC;
1743   return Ret.release();
1744 }
1745 
1746