forked from llvm/llvm-project
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathMachOObjectFile.cpp
2532 lines (2242 loc) · 79.1 KB
/
MachOObjectFile.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
//===- MachOObjectFile.cpp - Mach-O object file binding ---------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the MachOObjectFile class, which binds the MachOObject
// class to the generic ObjectFile wrapper.
//
//===----------------------------------------------------------------------===//
#include "llvm/Object/MachO.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Support/DataExtractor.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/Host.h"
#include "llvm/Support/LEB128.h"
#include "llvm/Support/MachO.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/raw_ostream.h"
#include <cctype>
#include <cstring>
#include <limits>
using namespace llvm;
using namespace object;
namespace {
struct section_base {
char sectname[16];
char segname[16];
};
}
template<typename T>
static T getStruct(const MachOObjectFile *O, const char *P) {
T Cmd;
memcpy(&Cmd, P, sizeof(T));
if (O->isLittleEndian() != sys::IsLittleEndianHost)
MachO::swapStruct(Cmd);
return Cmd;
}
static uint32_t
getSegmentLoadCommandNumSections(const MachOObjectFile *O,
const MachOObjectFile::LoadCommandInfo &L) {
if (O->is64Bit()) {
MachO::segment_command_64 S = O->getSegment64LoadCommand(L);
return S.nsects;
}
MachO::segment_command S = O->getSegmentLoadCommand(L);
return S.nsects;
}
static bool isPageZeroSegment(const MachOObjectFile *O,
const MachOObjectFile::LoadCommandInfo &L) {
if (O->is64Bit()) {
MachO::segment_command_64 S = O->getSegment64LoadCommand(L);
return StringRef("__PAGEZERO").equals(S.segname);
}
MachO::segment_command S = O->getSegmentLoadCommand(L);
return StringRef("__PAGEZERO").equals(S.segname);
}
static const char *
getSectionPtr(const MachOObjectFile *O, MachOObjectFile::LoadCommandInfo L,
unsigned Sec) {
uintptr_t CommandAddr = reinterpret_cast<uintptr_t>(L.Ptr);
bool Is64 = O->is64Bit();
unsigned SegmentLoadSize = Is64 ? sizeof(MachO::segment_command_64) :
sizeof(MachO::segment_command);
unsigned SectionSize = Is64 ? sizeof(MachO::section_64) :
sizeof(MachO::section);
uintptr_t SectionAddr = CommandAddr + SegmentLoadSize + Sec * SectionSize;
return reinterpret_cast<const char*>(SectionAddr);
}
static const char *getPtr(const MachOObjectFile *O, size_t Offset) {
return O->getData().substr(Offset, 1).data();
}
static MachO::nlist_base
getSymbolTableEntryBase(const MachOObjectFile *O, DataRefImpl DRI) {
const char *P = reinterpret_cast<const char *>(DRI.p);
return getStruct<MachO::nlist_base>(O, P);
}
static StringRef parseSegmentOrSectionName(const char *P) {
if (P[15] == 0)
// Null terminated.
return P;
// Not null terminated, so this is a 16 char string.
return StringRef(P, 16);
}
// Helper to advance a section or symbol iterator multiple increments at a time.
template<class T>
static void advance(T &it, size_t Val) {
while (Val--)
++it;
}
static unsigned getCPUType(const MachOObjectFile *O) {
return O->getHeader().cputype;
}
static void printRelocationTargetName(const MachOObjectFile *O,
const MachO::any_relocation_info &RE,
raw_string_ostream &fmt) {
bool IsScattered = O->isRelocationScattered(RE);
// Target of a scattered relocation is an address. In the interest of
// generating pretty output, scan through the symbol table looking for a
// symbol that aligns with that address. If we find one, print it.
// Otherwise, we just print the hex address of the target.
if (IsScattered) {
uint32_t Val = O->getPlainRelocationSymbolNum(RE);
for (const SymbolRef &Symbol : O->symbols()) {
std::error_code ec;
uint64_t Addr;
StringRef Name;
if ((ec = Symbol.getAddress(Addr)))
report_fatal_error(ec.message());
if (Addr != Val)
continue;
if ((ec = Symbol.getName(Name)))
report_fatal_error(ec.message());
fmt << Name;
return;
}
// If we couldn't find a symbol that this relocation refers to, try
// to find a section beginning instead.
for (const SectionRef &Section : O->sections()) {
std::error_code ec;
StringRef Name;
uint64_t Addr = Section.getAddress();
if (Addr != Val)
continue;
if ((ec = Section.getName(Name)))
report_fatal_error(ec.message());
fmt << Name;
return;
}
fmt << format("0x%x", Val);
return;
}
StringRef S;
bool isExtern = O->getPlainRelocationExternal(RE);
uint64_t Val = O->getPlainRelocationSymbolNum(RE);
if (isExtern) {
symbol_iterator SI = O->symbol_begin();
advance(SI, Val);
SI->getName(S);
} else {
section_iterator SI = O->section_begin();
// Adjust for the fact that sections are 1-indexed.
advance(SI, Val - 1);
SI->getName(S);
}
fmt << S;
}
static uint32_t
getPlainRelocationAddress(const MachO::any_relocation_info &RE) {
return RE.r_word0;
}
static unsigned
getScatteredRelocationAddress(const MachO::any_relocation_info &RE) {
return RE.r_word0 & 0xffffff;
}
static bool getPlainRelocationPCRel(const MachOObjectFile *O,
const MachO::any_relocation_info &RE) {
if (O->isLittleEndian())
return (RE.r_word1 >> 24) & 1;
return (RE.r_word1 >> 7) & 1;
}
static bool
getScatteredRelocationPCRel(const MachOObjectFile *O,
const MachO::any_relocation_info &RE) {
return (RE.r_word0 >> 30) & 1;
}
static unsigned getPlainRelocationLength(const MachOObjectFile *O,
const MachO::any_relocation_info &RE) {
if (O->isLittleEndian())
return (RE.r_word1 >> 25) & 3;
return (RE.r_word1 >> 5) & 3;
}
static unsigned
getScatteredRelocationLength(const MachO::any_relocation_info &RE) {
return (RE.r_word0 >> 28) & 3;
}
static unsigned getPlainRelocationType(const MachOObjectFile *O,
const MachO::any_relocation_info &RE) {
if (O->isLittleEndian())
return RE.r_word1 >> 28;
return RE.r_word1 & 0xf;
}
static uint32_t getSectionFlags(const MachOObjectFile *O,
DataRefImpl Sec) {
if (O->is64Bit()) {
MachO::section_64 Sect = O->getSection64(Sec);
return Sect.flags;
}
MachO::section Sect = O->getSection(Sec);
return Sect.flags;
}
MachOObjectFile::MachOObjectFile(MemoryBufferRef Object, bool IsLittleEndian,
bool Is64bits, std::error_code &EC)
: ObjectFile(getMachOType(IsLittleEndian, Is64bits), Object),
SymtabLoadCmd(nullptr), DysymtabLoadCmd(nullptr),
DataInCodeLoadCmd(nullptr), DyldInfoLoadCmd(nullptr),
UuidLoadCmd(nullptr), HasPageZeroSegment(false) {
uint32_t LoadCommandCount = this->getHeader().ncmds;
MachO::LoadCommandType SegmentLoadType = is64Bit() ?
MachO::LC_SEGMENT_64 : MachO::LC_SEGMENT;
MachOObjectFile::LoadCommandInfo Load = getFirstLoadCommandInfo();
for (unsigned I = 0; ; ++I) {
if (Load.C.cmd == MachO::LC_SYMTAB) {
// Multiple symbol tables
if (SymtabLoadCmd) {
EC = object_error::parse_failed;
return;
}
SymtabLoadCmd = Load.Ptr;
} else if (Load.C.cmd == MachO::LC_DYSYMTAB) {
// Multiple dynamic symbol tables
if (DysymtabLoadCmd) {
EC = object_error::parse_failed;
return;
}
DysymtabLoadCmd = Load.Ptr;
} else if (Load.C.cmd == MachO::LC_DATA_IN_CODE) {
// Multiple data in code tables
if (DataInCodeLoadCmd) {
EC = object_error::parse_failed;
return;
}
DataInCodeLoadCmd = Load.Ptr;
} else if (Load.C.cmd == MachO::LC_DYLD_INFO ||
Load.C.cmd == MachO::LC_DYLD_INFO_ONLY) {
// Multiple dyldinfo load commands
if (DyldInfoLoadCmd) {
EC = object_error::parse_failed;
return;
}
DyldInfoLoadCmd = Load.Ptr;
} else if (Load.C.cmd == MachO::LC_UUID) {
// Multiple UUID load commands
if (UuidLoadCmd) {
EC = object_error::parse_failed;
return;
}
UuidLoadCmd = Load.Ptr;
} else if (Load.C.cmd == SegmentLoadType) {
uint32_t NumSections = getSegmentLoadCommandNumSections(this, Load);
for (unsigned J = 0; J < NumSections; ++J) {
const char *Sec = getSectionPtr(this, Load, J);
Sections.push_back(Sec);
}
if (isPageZeroSegment(this, Load))
HasPageZeroSegment = true;
} else if (Load.C.cmd == MachO::LC_LOAD_DYLIB ||
Load.C.cmd == MachO::LC_LOAD_WEAK_DYLIB ||
Load.C.cmd == MachO::LC_LAZY_LOAD_DYLIB ||
Load.C.cmd == MachO::LC_REEXPORT_DYLIB ||
Load.C.cmd == MachO::LC_LOAD_UPWARD_DYLIB) {
Libraries.push_back(Load.Ptr);
}
if (I == LoadCommandCount - 1)
break;
else
Load = getNextLoadCommandInfo(Load);
}
}
void MachOObjectFile::moveSymbolNext(DataRefImpl &Symb) const {
unsigned SymbolTableEntrySize = is64Bit() ?
sizeof(MachO::nlist_64) :
sizeof(MachO::nlist);
Symb.p += SymbolTableEntrySize;
}
std::error_code MachOObjectFile::getSymbolName(DataRefImpl Symb,
StringRef &Res) const {
StringRef StringTable = getStringTableData();
MachO::nlist_base Entry = getSymbolTableEntryBase(this, Symb);
const char *Start = &StringTable.data()[Entry.n_strx];
Res = StringRef(Start);
return object_error::success;
}
// getIndirectName() returns the name of the alias'ed symbol who's string table
// index is in the n_value field.
std::error_code MachOObjectFile::getIndirectName(DataRefImpl Symb,
StringRef &Res) const {
StringRef StringTable = getStringTableData();
uint64_t NValue;
if (is64Bit()) {
MachO::nlist_64 Entry = getSymbol64TableEntry(Symb);
NValue = Entry.n_value;
if ((Entry.n_type & MachO::N_TYPE) != MachO::N_INDR)
return object_error::parse_failed;
} else {
MachO::nlist Entry = getSymbolTableEntry(Symb);
NValue = Entry.n_value;
if ((Entry.n_type & MachO::N_TYPE) != MachO::N_INDR)
return object_error::parse_failed;
}
if (NValue >= StringTable.size())
return object_error::parse_failed;
const char *Start = &StringTable.data()[NValue];
Res = StringRef(Start);
return object_error::success;
}
std::error_code MachOObjectFile::getSymbolAddress(DataRefImpl Symb,
uint64_t &Res) const {
if (is64Bit()) {
MachO::nlist_64 Entry = getSymbol64TableEntry(Symb);
if ((Entry.n_type & MachO::N_TYPE) == MachO::N_UNDF &&
Entry.n_value == 0)
Res = UnknownAddressOrSize;
else
Res = Entry.n_value;
} else {
MachO::nlist Entry = getSymbolTableEntry(Symb);
if ((Entry.n_type & MachO::N_TYPE) == MachO::N_UNDF &&
Entry.n_value == 0)
Res = UnknownAddressOrSize;
else
Res = Entry.n_value;
}
return object_error::success;
}
std::error_code MachOObjectFile::getSymbolAlignment(DataRefImpl DRI,
uint32_t &Result) const {
uint32_t flags = getSymbolFlags(DRI);
if (flags & SymbolRef::SF_Common) {
MachO::nlist_base Entry = getSymbolTableEntryBase(this, DRI);
Result = 1 << MachO::GET_COMM_ALIGN(Entry.n_desc);
} else {
Result = 0;
}
return object_error::success;
}
std::error_code MachOObjectFile::getSymbolSize(DataRefImpl DRI,
uint64_t &Result) const {
uint64_t BeginOffset;
uint64_t EndOffset = 0;
uint8_t SectionIndex;
MachO::nlist_base Entry = getSymbolTableEntryBase(this, DRI);
uint64_t Value;
getSymbolAddress(DRI, Value);
if (Value == UnknownAddressOrSize) {
Result = UnknownAddressOrSize;
return object_error::success;
}
BeginOffset = Value;
SectionIndex = Entry.n_sect;
if (!SectionIndex) {
uint32_t flags = getSymbolFlags(DRI);
if (flags & SymbolRef::SF_Common)
Result = Value;
else
Result = UnknownAddressOrSize;
return object_error::success;
}
// Unfortunately symbols are unsorted so we need to touch all
// symbols from load command
for (const SymbolRef &Symbol : symbols()) {
DataRefImpl DRI = Symbol.getRawDataRefImpl();
Entry = getSymbolTableEntryBase(this, DRI);
getSymbolAddress(DRI, Value);
if (Value == UnknownAddressOrSize)
continue;
if (Entry.n_sect == SectionIndex && Value > BeginOffset)
if (!EndOffset || Value < EndOffset)
EndOffset = Value;
}
if (!EndOffset) {
DataRefImpl Sec;
Sec.d.a = SectionIndex-1;
uint64_t Size = getSectionSize(Sec);
EndOffset = getSectionAddress(Sec);
EndOffset += Size;
}
Result = EndOffset - BeginOffset;
return object_error::success;
}
std::error_code MachOObjectFile::getSymbolType(DataRefImpl Symb,
SymbolRef::Type &Res) const {
MachO::nlist_base Entry = getSymbolTableEntryBase(this, Symb);
uint8_t n_type = Entry.n_type;
Res = SymbolRef::ST_Other;
// If this is a STAB debugging symbol, we can do nothing more.
if (n_type & MachO::N_STAB) {
Res = SymbolRef::ST_Debug;
return object_error::success;
}
switch (n_type & MachO::N_TYPE) {
case MachO::N_UNDF :
Res = SymbolRef::ST_Unknown;
break;
case MachO::N_SECT :
Res = SymbolRef::ST_Function;
break;
}
return object_error::success;
}
uint32_t MachOObjectFile::getSymbolFlags(DataRefImpl DRI) const {
MachO::nlist_base Entry = getSymbolTableEntryBase(this, DRI);
uint8_t MachOType = Entry.n_type;
uint16_t MachOFlags = Entry.n_desc;
uint32_t Result = SymbolRef::SF_None;
if ((MachOType & MachO::N_TYPE) == MachO::N_UNDF)
Result |= SymbolRef::SF_Undefined;
if ((MachOType & MachO::N_TYPE) == MachO::N_INDR)
Result |= SymbolRef::SF_Indirect;
if (MachOType & MachO::N_STAB)
Result |= SymbolRef::SF_FormatSpecific;
if (MachOType & MachO::N_EXT) {
Result |= SymbolRef::SF_Global;
if ((MachOType & MachO::N_TYPE) == MachO::N_UNDF) {
uint64_t Value;
getSymbolAddress(DRI, Value);
if (Value && Value != UnknownAddressOrSize)
Result |= SymbolRef::SF_Common;
}
}
if (MachOFlags & (MachO::N_WEAK_REF | MachO::N_WEAK_DEF))
Result |= SymbolRef::SF_Weak;
if (MachOFlags & (MachO::N_ARM_THUMB_DEF))
Result |= SymbolRef::SF_Thumb;
if ((MachOType & MachO::N_TYPE) == MachO::N_ABS)
Result |= SymbolRef::SF_Absolute;
return Result;
}
std::error_code MachOObjectFile::getSymbolSection(DataRefImpl Symb,
section_iterator &Res) const {
MachO::nlist_base Entry = getSymbolTableEntryBase(this, Symb);
uint8_t index = Entry.n_sect;
if (index == 0) {
Res = section_end();
} else {
DataRefImpl DRI;
DRI.d.a = index - 1;
Res = section_iterator(SectionRef(DRI, this));
}
return object_error::success;
}
void MachOObjectFile::moveSectionNext(DataRefImpl &Sec) const {
Sec.d.a++;
}
std::error_code MachOObjectFile::getSectionName(DataRefImpl Sec,
StringRef &Result) const {
ArrayRef<char> Raw = getSectionRawName(Sec);
Result = parseSegmentOrSectionName(Raw.data());
return object_error::success;
}
uint64_t MachOObjectFile::getSectionAddress(DataRefImpl Sec) const {
if (is64Bit())
return getSection64(Sec).addr;
return getSection(Sec).addr;
}
uint64_t MachOObjectFile::getSectionSize(DataRefImpl Sec) const {
if (is64Bit())
return getSection64(Sec).size;
return getSection(Sec).size;
}
std::error_code MachOObjectFile::getSectionContents(DataRefImpl Sec,
StringRef &Res) const {
uint32_t Offset;
uint64_t Size;
if (is64Bit()) {
MachO::section_64 Sect = getSection64(Sec);
Offset = Sect.offset;
Size = Sect.size;
} else {
MachO::section Sect = getSection(Sec);
Offset = Sect.offset;
Size = Sect.size;
}
Res = this->getData().substr(Offset, Size);
return object_error::success;
}
uint64_t MachOObjectFile::getSectionAlignment(DataRefImpl Sec) const {
uint32_t Align;
if (is64Bit()) {
MachO::section_64 Sect = getSection64(Sec);
Align = Sect.align;
} else {
MachO::section Sect = getSection(Sec);
Align = Sect.align;
}
return uint64_t(1) << Align;
}
bool MachOObjectFile::isSectionText(DataRefImpl Sec) const {
uint32_t Flags = getSectionFlags(this, Sec);
return Flags & MachO::S_ATTR_PURE_INSTRUCTIONS;
}
bool MachOObjectFile::isSectionData(DataRefImpl Sec) const {
uint32_t Flags = getSectionFlags(this, Sec);
unsigned SectionType = Flags & MachO::SECTION_TYPE;
return !(Flags & MachO::S_ATTR_PURE_INSTRUCTIONS) &&
!(SectionType == MachO::S_ZEROFILL ||
SectionType == MachO::S_GB_ZEROFILL);
}
bool MachOObjectFile::isSectionBSS(DataRefImpl Sec) const {
uint32_t Flags = getSectionFlags(this, Sec);
unsigned SectionType = Flags & MachO::SECTION_TYPE;
return !(Flags & MachO::S_ATTR_PURE_INSTRUCTIONS) &&
(SectionType == MachO::S_ZEROFILL ||
SectionType == MachO::S_GB_ZEROFILL);
}
bool MachOObjectFile::isSectionRequiredForExecution(DataRefImpl Sect) const {
// FIXME: Unimplemented.
return true;
}
bool MachOObjectFile::isSectionVirtual(DataRefImpl Sec) const {
// FIXME: Unimplemented.
return false;
}
bool MachOObjectFile::isSectionZeroInit(DataRefImpl Sec) const {
uint32_t Flags = getSectionFlags(this, Sec);
unsigned SectionType = Flags & MachO::SECTION_TYPE;
return SectionType == MachO::S_ZEROFILL ||
SectionType == MachO::S_GB_ZEROFILL;
}
bool MachOObjectFile::isSectionReadOnlyData(DataRefImpl Sec) const {
// Consider using the code from isSectionText to look for __const sections.
// Alternately, emit S_ATTR_PURE_INSTRUCTIONS and/or S_ATTR_SOME_INSTRUCTIONS
// to use section attributes to distinguish code from data.
// FIXME: Unimplemented.
return false;
}
bool MachOObjectFile::sectionContainsSymbol(DataRefImpl Sec,
DataRefImpl Symb) const {
SymbolRef::Type ST;
this->getSymbolType(Symb, ST);
if (ST == SymbolRef::ST_Unknown)
return false;
uint64_t SectBegin = getSectionAddress(Sec);
uint64_t SectEnd = getSectionSize(Sec);
SectEnd += SectBegin;
uint64_t SymAddr;
getSymbolAddress(Symb, SymAddr);
return (SymAddr >= SectBegin) && (SymAddr < SectEnd);
}
relocation_iterator MachOObjectFile::section_rel_begin(DataRefImpl Sec) const {
DataRefImpl Ret;
Ret.d.a = Sec.d.a;
Ret.d.b = 0;
return relocation_iterator(RelocationRef(Ret, this));
}
relocation_iterator
MachOObjectFile::section_rel_end(DataRefImpl Sec) const {
uint32_t Num;
if (is64Bit()) {
MachO::section_64 Sect = getSection64(Sec);
Num = Sect.nreloc;
} else {
MachO::section Sect = getSection(Sec);
Num = Sect.nreloc;
}
DataRefImpl Ret;
Ret.d.a = Sec.d.a;
Ret.d.b = Num;
return relocation_iterator(RelocationRef(Ret, this));
}
void MachOObjectFile::moveRelocationNext(DataRefImpl &Rel) const {
++Rel.d.b;
}
std::error_code MachOObjectFile::getRelocationAddress(DataRefImpl Rel,
uint64_t &Res) const {
uint64_t Offset;
getRelocationOffset(Rel, Offset);
DataRefImpl Sec;
Sec.d.a = Rel.d.a;
uint64_t SecAddress = getSectionAddress(Sec);
Res = SecAddress + Offset;
return object_error::success;
}
std::error_code MachOObjectFile::getRelocationOffset(DataRefImpl Rel,
uint64_t &Res) const {
assert(getHeader().filetype == MachO::MH_OBJECT &&
"Only implemented for MH_OBJECT");
MachO::any_relocation_info RE = getRelocation(Rel);
Res = getAnyRelocationAddress(RE);
return object_error::success;
}
symbol_iterator
MachOObjectFile::getRelocationSymbol(DataRefImpl Rel) const {
MachO::any_relocation_info RE = getRelocation(Rel);
if (isRelocationScattered(RE))
return symbol_end();
uint32_t SymbolIdx = getPlainRelocationSymbolNum(RE);
bool isExtern = getPlainRelocationExternal(RE);
if (!isExtern)
return symbol_end();
MachO::symtab_command S = getSymtabLoadCommand();
unsigned SymbolTableEntrySize = is64Bit() ?
sizeof(MachO::nlist_64) :
sizeof(MachO::nlist);
uint64_t Offset = S.symoff + SymbolIdx * SymbolTableEntrySize;
DataRefImpl Sym;
Sym.p = reinterpret_cast<uintptr_t>(getPtr(this, Offset));
return symbol_iterator(SymbolRef(Sym, this));
}
std::error_code MachOObjectFile::getRelocationType(DataRefImpl Rel,
uint64_t &Res) const {
MachO::any_relocation_info RE = getRelocation(Rel);
Res = getAnyRelocationType(RE);
return object_error::success;
}
std::error_code
MachOObjectFile::getRelocationTypeName(DataRefImpl Rel,
SmallVectorImpl<char> &Result) const {
StringRef res;
uint64_t RType;
getRelocationType(Rel, RType);
unsigned Arch = this->getArch();
switch (Arch) {
case Triple::x86: {
static const char *const Table[] = {
"GENERIC_RELOC_VANILLA",
"GENERIC_RELOC_PAIR",
"GENERIC_RELOC_SECTDIFF",
"GENERIC_RELOC_PB_LA_PTR",
"GENERIC_RELOC_LOCAL_SECTDIFF",
"GENERIC_RELOC_TLV" };
if (RType > 5)
res = "Unknown";
else
res = Table[RType];
break;
}
case Triple::x86_64: {
static const char *const Table[] = {
"X86_64_RELOC_UNSIGNED",
"X86_64_RELOC_SIGNED",
"X86_64_RELOC_BRANCH",
"X86_64_RELOC_GOT_LOAD",
"X86_64_RELOC_GOT",
"X86_64_RELOC_SUBTRACTOR",
"X86_64_RELOC_SIGNED_1",
"X86_64_RELOC_SIGNED_2",
"X86_64_RELOC_SIGNED_4",
"X86_64_RELOC_TLV" };
if (RType > 9)
res = "Unknown";
else
res = Table[RType];
break;
}
case Triple::arm: {
static const char *const Table[] = {
"ARM_RELOC_VANILLA",
"ARM_RELOC_PAIR",
"ARM_RELOC_SECTDIFF",
"ARM_RELOC_LOCAL_SECTDIFF",
"ARM_RELOC_PB_LA_PTR",
"ARM_RELOC_BR24",
"ARM_THUMB_RELOC_BR22",
"ARM_THUMB_32BIT_BRANCH",
"ARM_RELOC_HALF",
"ARM_RELOC_HALF_SECTDIFF" };
if (RType > 9)
res = "Unknown";
else
res = Table[RType];
break;
}
case Triple::aarch64: {
static const char *const Table[] = {
"ARM64_RELOC_UNSIGNED", "ARM64_RELOC_SUBTRACTOR",
"ARM64_RELOC_BRANCH26", "ARM64_RELOC_PAGE21",
"ARM64_RELOC_PAGEOFF12", "ARM64_RELOC_GOT_LOAD_PAGE21",
"ARM64_RELOC_GOT_LOAD_PAGEOFF12", "ARM64_RELOC_POINTER_TO_GOT",
"ARM64_RELOC_TLVP_LOAD_PAGE21", "ARM64_RELOC_TLVP_LOAD_PAGEOFF12",
"ARM64_RELOC_ADDEND"
};
if (RType >= array_lengthof(Table))
res = "Unknown";
else
res = Table[RType];
break;
}
case Triple::ppc: {
static const char *const Table[] = {
"PPC_RELOC_VANILLA",
"PPC_RELOC_PAIR",
"PPC_RELOC_BR14",
"PPC_RELOC_BR24",
"PPC_RELOC_HI16",
"PPC_RELOC_LO16",
"PPC_RELOC_HA16",
"PPC_RELOC_LO14",
"PPC_RELOC_SECTDIFF",
"PPC_RELOC_PB_LA_PTR",
"PPC_RELOC_HI16_SECTDIFF",
"PPC_RELOC_LO16_SECTDIFF",
"PPC_RELOC_HA16_SECTDIFF",
"PPC_RELOC_JBSR",
"PPC_RELOC_LO14_SECTDIFF",
"PPC_RELOC_LOCAL_SECTDIFF" };
if (RType > 15)
res = "Unknown";
else
res = Table[RType];
break;
}
case Triple::UnknownArch:
res = "Unknown";
break;
}
Result.append(res.begin(), res.end());
return object_error::success;
}
std::error_code
MachOObjectFile::getRelocationValueString(DataRefImpl Rel,
SmallVectorImpl<char> &Result) const {
MachO::any_relocation_info RE = getRelocation(Rel);
unsigned Arch = this->getArch();
std::string fmtbuf;
raw_string_ostream fmt(fmtbuf);
unsigned Type = this->getAnyRelocationType(RE);
bool IsPCRel = this->getAnyRelocationPCRel(RE);
// Determine any addends that should be displayed with the relocation.
// These require decoding the relocation type, which is triple-specific.
// X86_64 has entirely custom relocation types.
if (Arch == Triple::x86_64) {
bool isPCRel = getAnyRelocationPCRel(RE);
switch (Type) {
case MachO::X86_64_RELOC_GOT_LOAD:
case MachO::X86_64_RELOC_GOT: {
printRelocationTargetName(this, RE, fmt);
fmt << "@GOT";
if (isPCRel) fmt << "PCREL";
break;
}
case MachO::X86_64_RELOC_SUBTRACTOR: {
DataRefImpl RelNext = Rel;
moveRelocationNext(RelNext);
MachO::any_relocation_info RENext = getRelocation(RelNext);
// X86_64_RELOC_SUBTRACTOR must be followed by a relocation of type
// X86_64_RELOC_UNSIGNED.
// NOTE: Scattered relocations don't exist on x86_64.
unsigned RType = getAnyRelocationType(RENext);
if (RType != MachO::X86_64_RELOC_UNSIGNED)
report_fatal_error("Expected X86_64_RELOC_UNSIGNED after "
"X86_64_RELOC_SUBTRACTOR.");
// The X86_64_RELOC_UNSIGNED contains the minuend symbol;
// X86_64_RELOC_SUBTRACTOR contains the subtrahend.
printRelocationTargetName(this, RENext, fmt);
fmt << "-";
printRelocationTargetName(this, RE, fmt);
break;
}
case MachO::X86_64_RELOC_TLV:
printRelocationTargetName(this, RE, fmt);
fmt << "@TLV";
if (isPCRel) fmt << "P";
break;
case MachO::X86_64_RELOC_SIGNED_1:
printRelocationTargetName(this, RE, fmt);
fmt << "-1";
break;
case MachO::X86_64_RELOC_SIGNED_2:
printRelocationTargetName(this, RE, fmt);
fmt << "-2";
break;
case MachO::X86_64_RELOC_SIGNED_4:
printRelocationTargetName(this, RE, fmt);
fmt << "-4";
break;
default:
printRelocationTargetName(this, RE, fmt);
break;
}
// X86 and ARM share some relocation types in common.
} else if (Arch == Triple::x86 || Arch == Triple::arm ||
Arch == Triple::ppc) {
// Generic relocation types...
switch (Type) {
case MachO::GENERIC_RELOC_PAIR: // prints no info
return object_error::success;
case MachO::GENERIC_RELOC_SECTDIFF: {
DataRefImpl RelNext = Rel;
moveRelocationNext(RelNext);
MachO::any_relocation_info RENext = getRelocation(RelNext);
// X86 sect diff's must be followed by a relocation of type
// GENERIC_RELOC_PAIR.
unsigned RType = getAnyRelocationType(RENext);
if (RType != MachO::GENERIC_RELOC_PAIR)
report_fatal_error("Expected GENERIC_RELOC_PAIR after "
"GENERIC_RELOC_SECTDIFF.");
printRelocationTargetName(this, RE, fmt);
fmt << "-";
printRelocationTargetName(this, RENext, fmt);
break;
}
}
if (Arch == Triple::x86 || Arch == Triple::ppc) {
switch (Type) {
case MachO::GENERIC_RELOC_LOCAL_SECTDIFF: {
DataRefImpl RelNext = Rel;
moveRelocationNext(RelNext);
MachO::any_relocation_info RENext = getRelocation(RelNext);
// X86 sect diff's must be followed by a relocation of type
// GENERIC_RELOC_PAIR.
unsigned RType = getAnyRelocationType(RENext);
if (RType != MachO::GENERIC_RELOC_PAIR)
report_fatal_error("Expected GENERIC_RELOC_PAIR after "
"GENERIC_RELOC_LOCAL_SECTDIFF.");
printRelocationTargetName(this, RE, fmt);
fmt << "-";
printRelocationTargetName(this, RENext, fmt);
break;
}
case MachO::GENERIC_RELOC_TLV: {
printRelocationTargetName(this, RE, fmt);
fmt << "@TLV";
if (IsPCRel) fmt << "P";
break;
}
default:
printRelocationTargetName(this, RE, fmt);
}
} else { // ARM-specific relocations
switch (Type) {
case MachO::ARM_RELOC_HALF:
case MachO::ARM_RELOC_HALF_SECTDIFF: {
// Half relocations steal a bit from the length field to encode
// whether this is an upper16 or a lower16 relocation.
bool isUpper = getAnyRelocationLength(RE) >> 1;
if (isUpper)
fmt << ":upper16:(";
else
fmt << ":lower16:(";
printRelocationTargetName(this, RE, fmt);
DataRefImpl RelNext = Rel;
moveRelocationNext(RelNext);
MachO::any_relocation_info RENext = getRelocation(RelNext);
// ARM half relocs must be followed by a relocation of type
// ARM_RELOC_PAIR.
unsigned RType = getAnyRelocationType(RENext);
if (RType != MachO::ARM_RELOC_PAIR)
report_fatal_error("Expected ARM_RELOC_PAIR after "
"ARM_RELOC_HALF");
// NOTE: The half of the target virtual address is stashed in the
// address field of the secondary relocation, but we can't reverse
// engineer the constant offset from it without decoding the movw/movt
// instruction to find the other half in its immediate field.
// ARM_RELOC_HALF_SECTDIFF encodes the second section in the
// symbol/section pointer of the follow-on relocation.
if (Type == MachO::ARM_RELOC_HALF_SECTDIFF) {
fmt << "-";
printRelocationTargetName(this, RENext, fmt);
}
fmt << ")";
break;
}
default: {
printRelocationTargetName(this, RE, fmt);
}
}
}
} else
printRelocationTargetName(this, RE, fmt);
fmt.flush();
Result.append(fmtbuf.begin(), fmtbuf.end());
return object_error::success;
}
std::error_code MachOObjectFile::getRelocationHidden(DataRefImpl Rel,
bool &Result) const {
unsigned Arch = getArch();
uint64_t Type;
getRelocationType(Rel, Type);
Result = false;
// On arches that use the generic relocations, GENERIC_RELOC_PAIR
// is always hidden.
if (Arch == Triple::x86 || Arch == Triple::arm || Arch == Triple::ppc) {
if (Type == MachO::GENERIC_RELOC_PAIR) Result = true;
} else if (Arch == Triple::x86_64) {
// On x86_64, X86_64_RELOC_UNSIGNED is hidden only when it follows
// an X86_64_RELOC_SUBTRACTOR.
if (Type == MachO::X86_64_RELOC_UNSIGNED && Rel.d.a > 0) {