aboutsummaryrefslogtreecommitdiffstats
path: root/include/clang/Basic/TargetInfo.h
blob: 9a3bb986930ef728ebc4cd257916897d933f577f (plain) (blame)
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
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
//===--- TargetInfo.h - Expose information about the target -----*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
///
/// \file
/// Defines the clang::TargetInfo interface.
///
//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_BASIC_TARGETINFO_H
#define LLVM_CLANG_BASIC_TARGETINFO_H

#include "clang/Basic/AddressSpaces.h"
#include "clang/Basic/LLVM.h"
#include "clang/Basic/Specifiers.h"
#include "clang/Basic/TargetCXXABI.h"
#include "clang/Basic/TargetOptions.h"
#include "llvm/ADT/APFloat.h"
#include "llvm/ADT/APInt.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/IntrusiveRefCntPtr.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Support/DataTypes.h"
#include "llvm/Support/VersionTuple.h"
#include <cassert>
#include <string>
#include <vector>

namespace llvm {
struct fltSemantics;
class DataLayout;
}

namespace clang {
class DiagnosticsEngine;
class LangOptions;
class CodeGenOptions;
class MacroBuilder;
class QualType;
class SourceLocation;
class SourceManager;

namespace Builtin { struct Info; }

/// Fields controlling how types are laid out in memory; these may need to
/// be copied for targets like AMDGPU that base their ABIs on an auxiliary
/// CPU target.
struct TransferrableTargetInfo {
  unsigned char PointerWidth, PointerAlign;
  unsigned char BoolWidth, BoolAlign;
  unsigned char IntWidth, IntAlign;
  unsigned char HalfWidth, HalfAlign;
  unsigned char FloatWidth, FloatAlign;
  unsigned char DoubleWidth, DoubleAlign;
  unsigned char LongDoubleWidth, LongDoubleAlign, Float128Align;
  unsigned char LargeArrayMinWidth, LargeArrayAlign;
  unsigned char LongWidth, LongAlign;
  unsigned char LongLongWidth, LongLongAlign;

  // Fixed point bit widths
  unsigned char ShortAccumWidth, ShortAccumAlign;
  unsigned char AccumWidth, AccumAlign;
  unsigned char LongAccumWidth, LongAccumAlign;
  unsigned char ShortFractWidth, ShortFractAlign;
  unsigned char FractWidth, FractAlign;
  unsigned char LongFractWidth, LongFractAlign;

  // If true, unsigned fixed point types have the same number of fractional bits
  // as their signed counterparts, forcing the unsigned types to have one extra
  // bit of padding. Otherwise, unsigned fixed point types have
  // one more fractional bit than its corresponding signed type. This is false
  // by default.
  bool PaddingOnUnsignedFixedPoint;

  // Fixed point integral and fractional bit sizes
  // Saturated types share the same integral/fractional bits as their
  // corresponding unsaturated types.
  // For simplicity, the fractional bits in a _Fract type will be one less the
  // width of that _Fract type. This leaves all signed _Fract types having no
  // padding and unsigned _Fract types will only have 1 bit of padding after the
  // sign if PaddingOnUnsignedFixedPoint is set.
  unsigned char ShortAccumScale;
  unsigned char AccumScale;
  unsigned char LongAccumScale;

  unsigned char SuitableAlign;
  unsigned char DefaultAlignForAttributeAligned;
  unsigned char MinGlobalAlign;

  unsigned short NewAlign;
  unsigned short MaxVectorAlign;
  unsigned short MaxTLSAlign;

  const llvm::fltSemantics *HalfFormat, *FloatFormat, *DoubleFormat,
    *LongDoubleFormat, *Float128Format;

  ///===---- Target Data Type Query Methods -------------------------------===//
  enum IntType {
    NoInt = 0,
    SignedChar,
    UnsignedChar,
    SignedShort,
    UnsignedShort,
    SignedInt,
    UnsignedInt,
    SignedLong,
    UnsignedLong,
    SignedLongLong,
    UnsignedLongLong
  };

  enum RealType {
    NoFloat = 255,
    Float = 0,
    Double,
    LongDouble,
    Float128
  };
protected:
  IntType SizeType, IntMaxType, PtrDiffType, IntPtrType, WCharType,
          WIntType, Char16Type, Char32Type, Int64Type, SigAtomicType,
          ProcessIDType;

  /// Whether Objective-C's built-in boolean type should be signed char.
  ///
  /// Otherwise, when this flag is not set, the normal built-in boolean type is
  /// used.
  unsigned UseSignedCharForObjCBool : 1;

  /// Control whether the alignment of bit-field types is respected when laying
  /// out structures. If true, then the alignment of the bit-field type will be
  /// used to (a) impact the alignment of the containing structure, and (b)
  /// ensure that the individual bit-field will not straddle an alignment
  /// boundary.
  unsigned UseBitFieldTypeAlignment : 1;

  /// Whether zero length bitfields (e.g., int : 0;) force alignment of
  /// the next bitfield.
  ///
  /// If the alignment of the zero length bitfield is greater than the member
  /// that follows it, `bar', `bar' will be aligned as the type of the
  /// zero-length bitfield.
  unsigned UseZeroLengthBitfieldAlignment : 1;

  ///  Whether explicit bit field alignment attributes are honored.
  unsigned UseExplicitBitFieldAlignment : 1;

  /// If non-zero, specifies a fixed alignment value for bitfields that follow
  /// zero length bitfield, regardless of the zero length bitfield type.
  unsigned ZeroLengthBitfieldBoundary;
};

/// Exposes information about the current target.
///
class TargetInfo : public virtual TransferrableTargetInfo,
                   public RefCountedBase<TargetInfo> {
  std::shared_ptr<TargetOptions> TargetOpts;
  llvm::Triple Triple;
protected:
  // Target values set by the ctor of the actual target implementation.  Default
  // values are specified by the TargetInfo constructor.
  bool BigEndian;
  bool TLSSupported;
  bool VLASupported;
  bool NoAsmVariants;  // True if {|} are normal characters.
  bool HasLegalHalfType; // True if the backend supports operations on the half
                         // LLVM IR type.
  bool HasFloat128;
  bool HasFloat16;

  unsigned char MaxAtomicPromoteWidth, MaxAtomicInlineWidth;
  unsigned short SimdDefaultAlign;
  std::unique_ptr<llvm::DataLayout> DataLayout;
  const char *MCountName;
  unsigned char RegParmMax, SSERegParmMax;
  TargetCXXABI TheCXXABI;
  const LangASMap *AddrSpaceMap;

  mutable StringRef PlatformName;
  mutable VersionTuple PlatformMinVersion;

  unsigned HasAlignMac68kSupport : 1;
  unsigned RealTypeUsesObjCFPRet : 3;
  unsigned ComplexLongDoubleUsesFP2Ret : 1;

  unsigned HasBuiltinMSVaList : 1;

  unsigned IsRenderScriptTarget : 1;

  unsigned HasAArch64SVETypes : 1;

  // TargetInfo Constructor.  Default initializes all fields.
  TargetInfo(const llvm::Triple &T);

  void resetDataLayout(StringRef DL);

public:
  /// Construct a target for the given options.
  ///
  /// \param Opts - The options to use to initialize the target. The target may
  /// modify the options to canonicalize the target feature information to match
  /// what the backend expects.
  static TargetInfo *
  CreateTargetInfo(DiagnosticsEngine &Diags,
                   const std::shared_ptr<TargetOptions> &Opts);

  virtual ~TargetInfo();

  /// Retrieve the target options.
  TargetOptions &getTargetOpts() const {
    assert(TargetOpts && "Missing target options");
    return *TargetOpts;
  }

  /// The different kinds of __builtin_va_list types defined by
  /// the target implementation.
  enum BuiltinVaListKind {
    /// typedef char* __builtin_va_list;
    CharPtrBuiltinVaList = 0,

    /// typedef void* __builtin_va_list;
    VoidPtrBuiltinVaList,

    /// __builtin_va_list as defined by the AArch64 ABI
    /// http://infocenter.arm.com/help/topic/com.arm.doc.ihi0055a/IHI0055A_aapcs64.pdf
    AArch64ABIBuiltinVaList,

    /// __builtin_va_list as defined by the PNaCl ABI:
    /// http://www.chromium.org/nativeclient/pnacl/bitcode-abi#TOC-Machine-Types
    PNaClABIBuiltinVaList,

    /// __builtin_va_list as defined by the Power ABI:
    /// https://www.power.org
    ///        /resources/downloads/Power-Arch-32-bit-ABI-supp-1.0-Embedded.pdf
    PowerABIBuiltinVaList,

    /// __builtin_va_list as defined by the x86-64 ABI:
    /// http://refspecs.linuxbase.org/elf/x86_64-abi-0.21.pdf
    X86_64ABIBuiltinVaList,

    /// __builtin_va_list as defined by ARM AAPCS ABI
    /// http://infocenter.arm.com
    //        /help/topic/com.arm.doc.ihi0042d/IHI0042D_aapcs.pdf
    AAPCSABIBuiltinVaList,

    // typedef struct __va_list_tag
    //   {
    //     long __gpr;
    //     long __fpr;
    //     void *__overflow_arg_area;
    //     void *__reg_save_area;
    //   } va_list[1];
    SystemZBuiltinVaList
  };

protected:
  /// Specify if mangling based on address space map should be used or
  /// not for language specific address spaces
  bool UseAddrSpaceMapMangling;

public:
  IntType getSizeType() const { return SizeType; }
  IntType getSignedSizeType() const {
    switch (SizeType) {
    case UnsignedShort:
      return SignedShort;
    case UnsignedInt:
      return SignedInt;
    case UnsignedLong:
      return SignedLong;
    case UnsignedLongLong:
      return SignedLongLong;
    default:
      llvm_unreachable("Invalid SizeType");
    }
  }
  IntType getIntMaxType() const { return IntMaxType; }
  IntType getUIntMaxType() const {
    return getCorrespondingUnsignedType(IntMaxType);
  }
  IntType getPtrDiffType(unsigned AddrSpace) const {
    return AddrSpace == 0 ? PtrDiffType : getPtrDiffTypeV(AddrSpace);
  }
  IntType getUnsignedPtrDiffType(unsigned AddrSpace) const {
    return getCorrespondingUnsignedType(getPtrDiffType(AddrSpace));
  }
  IntType getIntPtrType() const { return IntPtrType; }
  IntType getUIntPtrType() const {
    return getCorrespondingUnsignedType(IntPtrType);
  }
  IntType getWCharType() const { return WCharType; }
  IntType getWIntType() const { return WIntType; }
  IntType getChar16Type() const { return Char16Type; }
  IntType getChar32Type() const { return Char32Type; }
  IntType getInt64Type() const { return Int64Type; }
  IntType getUInt64Type() const {
    return getCorrespondingUnsignedType(Int64Type);
  }
  IntType getSigAtomicType() const { return SigAtomicType; }
  IntType getProcessIDType() const { return ProcessIDType; }

  static IntType getCorrespondingUnsignedType(IntType T) {
    switch (T) {
    case SignedChar:
      return UnsignedChar;
    case SignedShort:
      return UnsignedShort;
    case SignedInt:
      return UnsignedInt;
    case SignedLong:
      return UnsignedLong;
    case SignedLongLong:
      return UnsignedLongLong;
    default:
      llvm_unreachable("Unexpected signed integer type");
    }
  }

  /// In the event this target uses the same number of fractional bits for its
  /// unsigned types as it does with its signed counterparts, there will be
  /// exactly one bit of padding.
  /// Return true if unsigned fixed point types have padding for this target.
  bool doUnsignedFixedPointTypesHavePadding() const {
    return PaddingOnUnsignedFixedPoint;
  }

  /// Return the width (in bits) of the specified integer type enum.
  ///
  /// For example, SignedInt -> getIntWidth().
  unsigned getTypeWidth(IntType T) const;

  /// Return integer type with specified width.
  virtual IntType getIntTypeByWidth(unsigned BitWidth, bool IsSigned) const;

  /// Return the smallest integer type with at least the specified width.
  virtual IntType getLeastIntTypeByWidth(unsigned BitWidth,
                                         bool IsSigned) const;

  /// Return floating point type with specified width.
  RealType getRealTypeByWidth(unsigned BitWidth) const;

  /// Return the alignment (in bits) of the specified integer type enum.
  ///
  /// For example, SignedInt -> getIntAlign().
  unsigned getTypeAlign(IntType T) const;

  /// Returns true if the type is signed; false otherwise.
  static bool isTypeSigned(IntType T);

  /// Return the width of pointers on this target, for the
  /// specified address space.
  uint64_t getPointerWidth(unsigned AddrSpace) const {
    return AddrSpace == 0 ? PointerWidth : getPointerWidthV(AddrSpace);
  }
  uint64_t getPointerAlign(unsigned AddrSpace) const {
    return AddrSpace == 0 ? PointerAlign : getPointerAlignV(AddrSpace);
  }

  /// Return the maximum width of pointers on this target.
  virtual uint64_t getMaxPointerWidth() const {
    return PointerWidth;
  }

  /// Get integer value for null pointer.
  /// \param AddrSpace address space of pointee in source language.
  virtual uint64_t getNullPointerValue(LangAS AddrSpace) const { return 0; }

  /// Return the size of '_Bool' and C++ 'bool' for this target, in bits.
  unsigned getBoolWidth() const { return BoolWidth; }

  /// Return the alignment of '_Bool' and C++ 'bool' for this target.
  unsigned getBoolAlign() const { return BoolAlign; }

  unsigned getCharWidth() const { return 8; } // FIXME
  unsigned getCharAlign() const { return 8; } // FIXME

  /// Return the size of 'signed short' and 'unsigned short' for this
  /// target, in bits.
  unsigned getShortWidth() const { return 16; } // FIXME

  /// Return the alignment of 'signed short' and 'unsigned short' for
  /// this target.
  unsigned getShortAlign() const { return 16; } // FIXME

  /// getIntWidth/Align - Return the size of 'signed int' and 'unsigned int' for
  /// this target, in bits.
  unsigned getIntWidth() const { return IntWidth; }
  unsigned getIntAlign() const { return IntAlign; }

  /// getLongWidth/Align - Return the size of 'signed long' and 'unsigned long'
  /// for this target, in bits.
  unsigned getLongWidth() const { return LongWidth; }
  unsigned getLongAlign() const { return LongAlign; }

  /// getLongLongWidth/Align - Return the size of 'signed long long' and
  /// 'unsigned long long' for this target, in bits.
  unsigned getLongLongWidth() const { return LongLongWidth; }
  unsigned getLongLongAlign() const { return LongLongAlign; }

  /// getShortAccumWidth/Align - Return the size of 'signed short _Accum' and
  /// 'unsigned short _Accum' for this target, in bits.
  unsigned getShortAccumWidth() const { return ShortAccumWidth; }
  unsigned getShortAccumAlign() const { return ShortAccumAlign; }

  /// getAccumWidth/Align - Return the size of 'signed _Accum' and
  /// 'unsigned _Accum' for this target, in bits.
  unsigned getAccumWidth() const { return AccumWidth; }
  unsigned getAccumAlign() const { return AccumAlign; }

  /// getLongAccumWidth/Align - Return the size of 'signed long _Accum' and
  /// 'unsigned long _Accum' for this target, in bits.
  unsigned getLongAccumWidth() const { return LongAccumWidth; }
  unsigned getLongAccumAlign() const { return LongAccumAlign; }

  /// getShortFractWidth/Align - Return the size of 'signed short _Fract' and
  /// 'unsigned short _Fract' for this target, in bits.
  unsigned getShortFractWidth() const { return ShortFractWidth; }
  unsigned getShortFractAlign() const { return ShortFractAlign; }

  /// getFractWidth/Align - Return the size of 'signed _Fract' and
  /// 'unsigned _Fract' for this target, in bits.
  unsigned getFractWidth() const { return FractWidth; }
  unsigned getFractAlign() const { return FractAlign; }

  /// getLongFractWidth/Align - Return the size of 'signed long _Fract' and
  /// 'unsigned long _Fract' for this target, in bits.
  unsigned getLongFractWidth() const { return LongFractWidth; }
  unsigned getLongFractAlign() const { return LongFractAlign; }

  /// getShortAccumScale/IBits - Return the number of fractional/integral bits
  /// in a 'signed short _Accum' type.
  unsigned getShortAccumScale() const { return ShortAccumScale; }
  unsigned getShortAccumIBits() const {
    return ShortAccumWidth - ShortAccumScale - 1;
  }

  /// getAccumScale/IBits - Return the number of fractional/integral bits
  /// in a 'signed _Accum' type.
  unsigned getAccumScale() const { return AccumScale; }
  unsigned getAccumIBits() const { return AccumWidth - AccumScale - 1; }

  /// getLongAccumScale/IBits - Return the number of fractional/integral bits
  /// in a 'signed long _Accum' type.
  unsigned getLongAccumScale() const { return LongAccumScale; }
  unsigned getLongAccumIBits() const {
    return LongAccumWidth - LongAccumScale - 1;
  }

  /// getUnsignedShortAccumScale/IBits - Return the number of
  /// fractional/integral bits in a 'unsigned short _Accum' type.
  unsigned getUnsignedShortAccumScale() const {
    return PaddingOnUnsignedFixedPoint ? ShortAccumScale : ShortAccumScale + 1;
  }
  unsigned getUnsignedShortAccumIBits() const {
    return PaddingOnUnsignedFixedPoint
               ? getShortAccumIBits()
               : ShortAccumWidth - getUnsignedShortAccumScale();
  }

  /// getUnsignedAccumScale/IBits - Return the number of fractional/integral
  /// bits in a 'unsigned _Accum' type.
  unsigned getUnsignedAccumScale() const {
    return PaddingOnUnsignedFixedPoint ? AccumScale : AccumScale + 1;
  }
  unsigned getUnsignedAccumIBits() const {
    return PaddingOnUnsignedFixedPoint ? getAccumIBits()
                                       : AccumWidth - getUnsignedAccumScale();
  }

  /// getUnsignedLongAccumScale/IBits - Return the number of fractional/integral
  /// bits in a 'unsigned long _Accum' type.
  unsigned getUnsignedLongAccumScale() const {
    return PaddingOnUnsignedFixedPoint ? LongAccumScale : LongAccumScale + 1;
  }
  unsigned getUnsignedLongAccumIBits() const {
    return PaddingOnUnsignedFixedPoint
               ? getLongAccumIBits()
               : LongAccumWidth - getUnsignedLongAccumScale();
  }

  /// getShortFractScale - Return the number of fractional bits
  /// in a 'signed short _Fract' type.
  unsigned getShortFractScale() const { return ShortFractWidth - 1; }

  /// getFractScale - Return the number of fractional bits
  /// in a 'signed _Fract' type.
  unsigned getFractScale() const { return FractWidth - 1; }

  /// getLongFractScale - Return the number of fractional bits
  /// in a 'signed long _Fract' type.
  unsigned getLongFractScale() const { return LongFractWidth - 1; }

  /// getUnsignedShortFractScale - Return the number of fractional bits
  /// in a 'unsigned short _Fract' type.
  unsigned getUnsignedShortFractScale() const {
    return PaddingOnUnsignedFixedPoint ? getShortFractScale()
                                       : getShortFractScale() + 1;
  }

  /// getUnsignedFractScale - Return the number of fractional bits
  /// in a 'unsigned _Fract' type.
  unsigned getUnsignedFractScale() const {
    return PaddingOnUnsignedFixedPoint ? getFractScale() : getFractScale() + 1;
  }

  /// getUnsignedLongFractScale - Return the number of fractional bits
  /// in a 'unsigned long _Fract' type.
  unsigned getUnsignedLongFractScale() const {
    return PaddingOnUnsignedFixedPoint ? getLongFractScale()
                                       : getLongFractScale() + 1;
  }

  /// Determine whether the __int128 type is supported on this target.
  virtual bool hasInt128Type() const {
    return (getPointerWidth(0) >= 64) || getTargetOpts().ForceEnableInt128;
  } // FIXME

  /// Determine whether _Float16 is supported on this target.
  virtual bool hasLegalHalfType() const { return HasLegalHalfType; }

  /// Determine whether the __float128 type is supported on this target.
  virtual bool hasFloat128Type() const { return HasFloat128; }

  /// Determine whether the _Float16 type is supported on this target.
  virtual bool hasFloat16Type() const { return HasFloat16; }

  /// Return the alignment that is suitable for storing any
  /// object with a fundamental alignment requirement.
  unsigned getSuitableAlign() const { return SuitableAlign; }

  /// Return the default alignment for __attribute__((aligned)) on
  /// this target, to be used if no alignment value is specified.
  unsigned getDefaultAlignForAttributeAligned() const {
    return DefaultAlignForAttributeAligned;
  }

  /// getMinGlobalAlign - Return the minimum alignment of a global variable,
  /// unless its alignment is explicitly reduced via attributes.
  virtual unsigned getMinGlobalAlign (uint64_t) const {
    return MinGlobalAlign;
  }

  /// Return the largest alignment for which a suitably-sized allocation with
  /// '::operator new(size_t)' is guaranteed to produce a correctly-aligned
  /// pointer.
  unsigned getNewAlign() const {
    return NewAlign ? NewAlign : std::max(LongDoubleAlign, LongLongAlign);
  }

  /// getWCharWidth/Align - Return the size of 'wchar_t' for this target, in
  /// bits.
  unsigned getWCharWidth() const { return getTypeWidth(WCharType); }
  unsigned getWCharAlign() const { return getTypeAlign(WCharType); }

  /// getChar16Width/Align - Return the size of 'char16_t' for this target, in
  /// bits.
  unsigned getChar16Width() const { return getTypeWidth(Char16Type); }
  unsigned getChar16Align() const { return getTypeAlign(Char16Type); }

  /// getChar32Width/Align - Return the size of 'char32_t' for this target, in
  /// bits.
  unsigned getChar32Width() const { return getTypeWidth(Char32Type); }
  unsigned getChar32Align() const { return getTypeAlign(Char32Type); }

  /// getHalfWidth/Align/Format - Return the size/align/format of 'half'.
  unsigned getHalfWidth() const { return HalfWidth; }
  unsigned getHalfAlign() const { return HalfAlign; }
  const llvm::fltSemantics &getHalfFormat() const { return *HalfFormat; }

  /// getFloatWidth/Align/Format - Return the size/align/format of 'float'.
  unsigned getFloatWidth() const { return FloatWidth; }
  unsigned getFloatAlign() const { return FloatAlign; }
  const llvm::fltSemantics &getFloatFormat() const { return *FloatFormat; }

  /// getDoubleWidth/Align/Format - Return the size/align/format of 'double'.
  unsigned getDoubleWidth() const { return DoubleWidth; }
  unsigned getDoubleAlign() const { return DoubleAlign; }
  const llvm::fltSemantics &getDoubleFormat() const { return *DoubleFormat; }

  /// getLongDoubleWidth/Align/Format - Return the size/align/format of 'long
  /// double'.
  unsigned getLongDoubleWidth() const { return LongDoubleWidth; }
  unsigned getLongDoubleAlign() const { return LongDoubleAlign; }
  const llvm::fltSemantics &getLongDoubleFormat() const {
    return *LongDoubleFormat;
  }

  /// getFloat128Width/Align/Format - Return the size/align/format of
  /// '__float128'.
  unsigned getFloat128Width() const { return 128; }
  unsigned getFloat128Align() const { return Float128Align; }
  const llvm::fltSemantics &getFloat128Format() const {
    return *Float128Format;
  }

  /// Return the mangled code of long double.
  virtual const char *getLongDoubleMangling() const { return "e"; }

  /// Return the mangled code of __float128.
  virtual const char *getFloat128Mangling() const { return "g"; }

  /// Return the value for the C99 FLT_EVAL_METHOD macro.
  virtual unsigned getFloatEvalMethod() const { return 0; }

  // getLargeArrayMinWidth/Align - Return the minimum array size that is
  // 'large' and its alignment.
  unsigned getLargeArrayMinWidth() const { return LargeArrayMinWidth; }
  unsigned getLargeArrayAlign() const { return LargeArrayAlign; }

  /// Return the maximum width lock-free atomic operation which will
  /// ever be supported for the given target
  unsigned getMaxAtomicPromoteWidth() const { return MaxAtomicPromoteWidth; }
  /// Return the maximum width lock-free atomic operation which can be
  /// inlined given the supported features of the given target.
  unsigned getMaxAtomicInlineWidth() const { return MaxAtomicInlineWidth; }
  /// Set the maximum inline or promote width lock-free atomic operation
  /// for the given target.
  virtual void setMaxAtomicWidth() {}
  /// Returns true if the given target supports lock-free atomic
  /// operations at the specified width and alignment.
  virtual bool hasBuiltinAtomic(uint64_t AtomicSizeInBits,
                                uint64_t AlignmentInBits) const {
    return AtomicSizeInBits <= AlignmentInBits &&
           AtomicSizeInBits <= getMaxAtomicInlineWidth() &&
           (AtomicSizeInBits <= getCharWidth() ||
            llvm::isPowerOf2_64(AtomicSizeInBits / getCharWidth()));
  }

  /// Return the maximum vector alignment supported for the given target.
  unsigned getMaxVectorAlign() const { return MaxVectorAlign; }
  /// Return default simd alignment for the given target. Generally, this
  /// value is type-specific, but this alignment can be used for most of the
  /// types for the given target.
  unsigned getSimdDefaultAlign() const { return SimdDefaultAlign; }

  /// Return the alignment (in bits) of the thrown exception object. This is
  /// only meaningful for targets that allocate C++ exceptions in a system
  /// runtime, such as those using the Itanium C++ ABI.
  virtual unsigned getExnObjectAlignment() const {
    // Itanium says that an _Unwind_Exception has to be "double-word"
    // aligned (and thus the end of it is also so-aligned), meaning 16
    // bytes.  Of course, that was written for the actual Itanium,
    // which is a 64-bit platform.  Classically, the ABI doesn't really
    // specify the alignment on other platforms, but in practice
    // libUnwind declares the struct with __attribute__((aligned)), so
    // we assume that alignment here.  (It's generally 16 bytes, but
    // some targets overwrite it.)
    return getDefaultAlignForAttributeAligned();
  }

  /// Return the size of intmax_t and uintmax_t for this target, in bits.
  unsigned getIntMaxTWidth() const {
    return getTypeWidth(IntMaxType);
  }

  // Return the size of unwind_word for this target.
  virtual unsigned getUnwindWordWidth() const { return getPointerWidth(0); }

  /// Return the "preferred" register width on this target.
  virtual unsigned getRegisterWidth() const {
    // Currently we assume the register width on the target matches the pointer
    // width, we can introduce a new variable for this if/when some target wants
    // it.
    return PointerWidth;
  }

  /// Returns the name of the mcount instrumentation function.
  const char *getMCountName() const {
    return MCountName;
  }

  /// Check if the Objective-C built-in boolean type should be signed
  /// char.
  ///
  /// Otherwise, if this returns false, the normal built-in boolean type
  /// should also be used for Objective-C.
  bool useSignedCharForObjCBool() const {
    return UseSignedCharForObjCBool;
  }
  void noSignedCharForObjCBool() {
    UseSignedCharForObjCBool = false;
  }

  /// Check whether the alignment of bit-field types is respected
  /// when laying out structures.
  bool useBitFieldTypeAlignment() const {
    return UseBitFieldTypeAlignment;
  }

  /// Check whether zero length bitfields should force alignment of
  /// the next member.
  bool useZeroLengthBitfieldAlignment() const {
    return UseZeroLengthBitfieldAlignment;
  }

  /// Get the fixed alignment value in bits for a member that follows
  /// a zero length bitfield.
  unsigned getZeroLengthBitfieldBoundary() const {
    return ZeroLengthBitfieldBoundary;
  }

  /// Check whether explicit bitfield alignment attributes should be
  //  honored, as in "__attribute__((aligned(2))) int b : 1;".
  bool useExplicitBitFieldAlignment() const {
    return UseExplicitBitFieldAlignment;
  }

  /// Check whether this target support '\#pragma options align=mac68k'.
  bool hasAlignMac68kSupport() const {
    return HasAlignMac68kSupport;
  }

  /// Return the user string for the specified integer type enum.
  ///
  /// For example, SignedShort -> "short".
  static const char *getTypeName(IntType T);

  /// Return the constant suffix for the specified integer type enum.
  ///
  /// For example, SignedLong -> "L".
  const char *getTypeConstantSuffix(IntType T) const;

  /// Return the printf format modifier for the specified
  /// integer type enum.
  ///
  /// For example, SignedLong -> "l".
  static const char *getTypeFormatModifier(IntType T);

  /// Check whether the given real type should use the "fpret" flavor of
  /// Objective-C message passing on this target.
  bool useObjCFPRetForRealType(RealType T) const {
    return RealTypeUsesObjCFPRet & (1 << T);
  }

  /// Check whether _Complex long double should use the "fp2ret" flavor
  /// of Objective-C message passing on this target.
  bool useObjCFP2RetForComplexLongDouble() const {
    return ComplexLongDoubleUsesFP2Ret;
  }

  /// Check whether llvm intrinsics such as llvm.convert.to.fp16 should be used
  /// to convert to and from __fp16.
  /// FIXME: This function should be removed once all targets stop using the
  /// conversion intrinsics.
  virtual bool useFP16ConversionIntrinsics() const {
    return true;
  }

  /// Specify if mangling based on address space map should be used or
  /// not for language specific address spaces
  bool useAddressSpaceMapMangling() const {
    return UseAddrSpaceMapMangling;
  }

  ///===---- Other target property query methods --------------------------===//

  /// Appends the target-specific \#define values for this
  /// target set to the specified buffer.
  virtual void getTargetDefines(const LangOptions &Opts,
                                MacroBuilder &Builder) const = 0;


  /// Return information about target-specific builtins for
  /// the current primary target, and info about which builtins are non-portable
  /// across the current set of primary and secondary targets.
  virtual ArrayRef<Builtin::Info> getTargetBuiltins() const = 0;

  /// The __builtin_clz* and __builtin_ctz* built-in
  /// functions are specified to have undefined results for zero inputs, but
  /// on targets that support these operations in a way that provides
  /// well-defined results for zero without loss of performance, it is a good
  /// idea to avoid optimizing based on that undef behavior.
  virtual bool isCLZForZeroUndef() const { return true; }

  /// Returns the kind of __builtin_va_list type that should be used
  /// with this target.
  virtual BuiltinVaListKind getBuiltinVaListKind() const = 0;

  /// Returns whether or not type \c __builtin_ms_va_list type is
  /// available on this target.
  bool hasBuiltinMSVaList() const { return HasBuiltinMSVaList; }

  /// Returns true for RenderScript.
  bool isRenderScriptTarget() const { return IsRenderScriptTarget; }

  /// Returns whether or not the AArch64 SVE built-in types are
  /// available on this target.
  bool hasAArch64SVETypes() const { return HasAArch64SVETypes; }

  /// Returns whether the passed in string is a valid clobber in an
  /// inline asm statement.
  ///
  /// This is used by Sema.
  bool isValidClobber(StringRef Name) const;

  /// Returns whether the passed in string is a valid register name
  /// according to GCC.
  ///
  /// This is used by Sema for inline asm statements.
  virtual bool isValidGCCRegisterName(StringRef Name) const;

  /// Returns the "normalized" GCC register name.
  ///
  /// ReturnCannonical true will return the register name without any additions
  /// such as "{}" or "%" in it's canonical form, for example:
  /// ReturnCanonical = true and Name = "rax", will return "ax".
  StringRef getNormalizedGCCRegisterName(StringRef Name,
                                         bool ReturnCanonical = false) const;

  /// Extracts a register from the passed constraint (if it is a
  /// single-register constraint) and the asm label expression related to a
  /// variable in the input or output list of an inline asm statement.
  ///
  /// This function is used by Sema in order to diagnose conflicts between
  /// the clobber list and the input/output lists.
  virtual StringRef getConstraintRegister(StringRef Constraint,
                                          StringRef Expression) const {
    return "";
  }

  struct ConstraintInfo {
    enum {
      CI_None = 0x00,
      CI_AllowsMemory = 0x01,
      CI_AllowsRegister = 0x02,
      CI_ReadWrite = 0x04,         // "+r" output constraint (read and write).
      CI_HasMatchingInput = 0x08,  // This output operand has a matching input.
      CI_ImmediateConstant = 0x10, // This operand must be an immediate constant
      CI_EarlyClobber = 0x20,      // "&" output constraint (early clobber).
    };
    unsigned Flags;
    int TiedOperand;
    struct {
      int Min;
      int Max;
      bool isConstrained;
    } ImmRange;
    llvm::SmallSet<int, 4> ImmSet;

    std::string ConstraintStr;  // constraint: "=rm"
    std::string Name;           // Operand name: [foo] with no []'s.
  public:
    ConstraintInfo(StringRef ConstraintStr, StringRef Name)
        : Flags(0), TiedOperand(-1), ConstraintStr(ConstraintStr.str()),
          Name(Name.str()) {
      ImmRange.Min = ImmRange.Max = 0;
      ImmRange.isConstrained = false;
    }

    const std::string &getConstraintStr() const { return ConstraintStr; }
    const std::string &getName() const { return Name; }
    bool isReadWrite() const { return (Flags & CI_ReadWrite) != 0; }
    bool earlyClobber() { return (Flags & CI_EarlyClobber) != 0; }
    bool allowsRegister() const { return (Flags & CI_AllowsRegister) != 0; }
    bool allowsMemory() const { return (Flags & CI_AllowsMemory) != 0; }

    /// Return true if this output operand has a matching
    /// (tied) input operand.
    bool hasMatchingInput() const { return (Flags & CI_HasMatchingInput) != 0; }

    /// Return true if this input operand is a matching
    /// constraint that ties it to an output operand.
    ///
    /// If this returns true then getTiedOperand will indicate which output
    /// operand this is tied to.
    bool hasTiedOperand() const { return TiedOperand != -1; }
    unsigned getTiedOperand() const {
      assert(hasTiedOperand() && "Has no tied operand!");
      return (unsigned)TiedOperand;
    }

    bool requiresImmediateConstant() const {
      return (Flags & CI_ImmediateConstant) != 0;
    }
    bool isValidAsmImmediate(const llvm::APInt &Value) const {
      if (!ImmSet.empty())
        return Value.isSignedIntN(32) &&
               ImmSet.count(Value.getZExtValue()) != 0;
      return !ImmRange.isConstrained ||
             (Value.sge(ImmRange.Min) && Value.sle(ImmRange.Max));
    }

    void setIsReadWrite() { Flags |= CI_ReadWrite; }
    void setEarlyClobber() { Flags |= CI_EarlyClobber; }
    void setAllowsMemory() { Flags |= CI_AllowsMemory; }
    void setAllowsRegister() { Flags |= CI_AllowsRegister; }
    void setHasMatchingInput() { Flags |= CI_HasMatchingInput; }
    void setRequiresImmediate(int Min, int Max) {
      Flags |= CI_ImmediateConstant;
      ImmRange.Min = Min;
      ImmRange.Max = Max;
      ImmRange.isConstrained = true;
    }
    void setRequiresImmediate(llvm::ArrayRef<int> Exacts) {
      Flags |= CI_ImmediateConstant;
      for (int Exact : Exacts)
        ImmSet.insert(Exact);
    }
    void setRequiresImmediate(int Exact) {
      Flags |= CI_ImmediateConstant;
      ImmSet.insert(Exact);
    }
    void setRequiresImmediate() {
      Flags |= CI_ImmediateConstant;
    }

    /// Indicate that this is an input operand that is tied to
    /// the specified output operand.
    ///
    /// Copy over the various constraint information from the output.
    void setTiedOperand(unsigned N, ConstraintInfo &Output) {
      Output.setHasMatchingInput();
      Flags = Output.Flags;
      TiedOperand = N;
      // Don't copy Name or constraint string.
    }
  };

  /// Validate register name used for global register variables.
  ///
  /// This function returns true if the register passed in RegName can be used
  /// for global register variables on this target. In addition, it returns
  /// true in HasSizeMismatch if the size of the register doesn't match the
  /// variable size passed in RegSize.
  virtual bool validateGlobalRegisterVariable(StringRef RegName,
                                              unsigned RegSize,
                                              bool &HasSizeMismatch) const {
    HasSizeMismatch = false;
    return true;
  }

  // validateOutputConstraint, validateInputConstraint - Checks that
  // a constraint is valid and provides information about it.
  // FIXME: These should return a real error instead of just true/false.
  bool validateOutputConstraint(ConstraintInfo &Info) const;
  bool validateInputConstraint(MutableArrayRef<ConstraintInfo> OutputConstraints,
                               ConstraintInfo &info) const;

  virtual bool validateOutputSize(StringRef /*Constraint*/,
                                  unsigned /*Size*/) const {
    return true;
  }

  virtual bool validateInputSize(StringRef /*Constraint*/,
                                 unsigned /*Size*/) const {
    return true;
  }
  virtual bool
  validateConstraintModifier(StringRef /*Constraint*/,
                             char /*Modifier*/,
                             unsigned /*Size*/,
                             std::string &/*SuggestedModifier*/) const {
    return true;
  }
  virtual bool
  validateAsmConstraint(const char *&Name,
                        TargetInfo::ConstraintInfo &info) const = 0;

  bool resolveSymbolicName(const char *&Name,
                           ArrayRef<ConstraintInfo> OutputConstraints,
                           unsigned &Index) const;

  // Constraint parm will be left pointing at the last character of
  // the constraint.  In practice, it won't be changed unless the
  // constraint is longer than one character.
  virtual std::string convertConstraint(const char *&Constraint) const {
    // 'p' defaults to 'r', but can be overridden by targets.
    if (*Constraint == 'p')
      return std::string("r");
    return std::string(1, *Constraint);
  }

  /// Returns a string of target-specific clobbers, in LLVM format.
  virtual const char *getClobbers() const = 0;

  /// Returns true if NaN encoding is IEEE 754-2008.
  /// Only MIPS allows a different encoding.
  virtual bool isNan2008() const {
    return true;
  }

  /// Returns the target triple of the primary target.
  const llvm::Triple &getTriple() const {
    return Triple;
  }

  const llvm::DataLayout &getDataLayout() const {
    assert(DataLayout && "Uninitialized DataLayout!");
    return *DataLayout;
  }

  struct GCCRegAlias {
    const char * const Aliases[5];
    const char * const Register;
  };

  struct AddlRegName {
    const char * const Names[5];
    const unsigned RegNum;
  };

  /// Does this target support "protected" visibility?
  ///
  /// Any target which dynamic libraries will naturally support
  /// something like "default" (meaning that the symbol is visible
  /// outside this shared object) and "hidden" (meaning that it isn't)
  /// visibilities, but "protected" is really an ELF-specific concept
  /// with weird semantics designed around the convenience of dynamic
  /// linker implementations.  Which is not to suggest that there's
  /// consistent target-independent semantics for "default" visibility
  /// either; the entire thing is pretty badly mangled.
  virtual bool hasProtectedVisibility() const { return true; }

  /// An optional hook that targets can implement to perform semantic
  /// checking on attribute((section("foo"))) specifiers.
  ///
  /// In this case, "foo" is passed in to be checked.  If the section
  /// specifier is invalid, the backend should return a non-empty string
  /// that indicates the problem.
  ///
  /// This hook is a simple quality of implementation feature to catch errors
  /// and give good diagnostics in cases when the assembler or code generator
  /// would otherwise reject the section specifier.
  ///
  virtual std::string isValidSectionSpecifier(StringRef SR) const {
    return "";
  }

  /// Set forced language options.
  ///
  /// Apply changes to the target information with respect to certain
  /// language options which change the target configuration and adjust
  /// the language based on the target options where applicable.
  virtual void adjust(LangOptions &Opts);

  /// Adjust target options based on codegen options.
  virtual void adjustTargetOptions(const CodeGenOptions &CGOpts,
                                   TargetOptions &TargetOpts) const {}

  /// Initialize the map with the default set of target features for the
  /// CPU this should include all legal feature strings on the target.
  ///
  /// \return False on error (invalid features).
  virtual bool initFeatureMap(llvm::StringMap<bool> &Features,
                              DiagnosticsEngine &Diags, StringRef CPU,
                              const std::vector<std::string> &FeatureVec) const;

  /// Get the ABI currently in use.
  virtual StringRef getABI() const { return StringRef(); }

  /// Get the C++ ABI currently in use.
  TargetCXXABI getCXXABI() const {
    return TheCXXABI;
  }

  /// Target the specified CPU.
  ///
  /// \return  False on error (invalid CPU name).
  virtual bool setCPU(const std::string &Name) {
    return false;
  }

  /// Fill a SmallVectorImpl with the valid values to setCPU.
  virtual void fillValidCPUList(SmallVectorImpl<StringRef> &Values) const {}

  /// brief Determine whether this TargetInfo supports the given CPU name.
  virtual bool isValidCPUName(StringRef Name) const {
    return true;
  }

  /// Use the specified ABI.
  ///
  /// \return False on error (invalid ABI name).
  virtual bool setABI(const std::string &Name) {
    return false;
  }

  /// Use the specified unit for FP math.
  ///
  /// \return False on error (invalid unit name).
  virtual bool setFPMath(StringRef Name) {
    return false;
  }

  /// Enable or disable a specific target feature;
  /// the feature name must be valid.
  virtual void setFeatureEnabled(llvm::StringMap<bool> &Features,
                                 StringRef Name,
                                 bool Enabled) const {
    Features[Name] = Enabled;
  }

  /// Determine whether this TargetInfo supports the given feature.
  virtual bool isValidFeatureName(StringRef Feature) const {
    return true;
  }

  /// Perform initialization based on the user configured
  /// set of features (e.g., +sse4).
  ///
  /// The list is guaranteed to have at most one entry per feature.
  ///
  /// The target may modify the features list, to change which options are
  /// passed onwards to the backend.
  /// FIXME: This part should be fixed so that we can change handleTargetFeatures
  /// to merely a TargetInfo initialization routine.
  ///
  /// \return  False on error.
  virtual bool handleTargetFeatures(std::vector<std::string> &Features,
                                    DiagnosticsEngine &Diags) {
    return true;
  }

  /// Determine whether the given target has the given feature.
  virtual bool hasFeature(StringRef Feature) const {
    return false;
  }

  /// Identify whether this target supports multiversioning of functions,
  /// which requires support for cpu_supports and cpu_is functionality.
  bool supportsMultiVersioning() const {
    return getTriple().getArch() == llvm::Triple::x86 ||
           getTriple().getArch() == llvm::Triple::x86_64;
  }

  /// Identify whether this target supports IFuncs.
  bool supportsIFunc() const { return getTriple().isOSBinFormatELF(); }

  // Validate the contents of the __builtin_cpu_supports(const char*)
  // argument.
  virtual bool validateCpuSupports(StringRef Name) const { return false; }

  // Return the target-specific priority for features/cpus/vendors so
  // that they can be properly sorted for checking.
  virtual unsigned multiVersionSortPriority(StringRef Name) const {
    return 0;
  }

  // Validate the contents of the __builtin_cpu_is(const char*)
  // argument.
  virtual bool validateCpuIs(StringRef Name) const { return false; }

  // Validate a cpu_dispatch/cpu_specific CPU option, which is a different list
  // from cpu_is, since it checks via features rather than CPUs directly.
  virtual bool validateCPUSpecificCPUDispatch(StringRef Name) const {
    return false;
  }

  // Get the character to be added for mangling purposes for cpu_specific.
  virtual char CPUSpecificManglingCharacter(StringRef Name) const {
    llvm_unreachable(
        "cpu_specific Multiversioning not implemented on this target");
  }

  // Get a list of the features that make up the CPU option for
  // cpu_specific/cpu_dispatch so that it can be passed to llvm as optimization
  // options.
  virtual void getCPUSpecificCPUDispatchFeatures(
      StringRef Name, llvm::SmallVectorImpl<StringRef> &Features) const {
    llvm_unreachable(
        "cpu_specific Multiversioning not implemented on this target");
  }

  // Returns maximal number of args passed in registers.
  unsigned getRegParmMax() const {
    assert(RegParmMax < 7 && "RegParmMax value is larger than AST can handle");
    return RegParmMax;
  }

  /// Whether the target supports thread-local storage.
  bool isTLSSupported() const {
    return TLSSupported;
  }

  /// Return the maximum alignment (in bits) of a TLS variable
  ///
  /// Gets the maximum alignment (in bits) of a TLS variable on this target.
  /// Returns zero if there is no such constraint.
  unsigned short getMaxTLSAlign() const {
    return MaxTLSAlign;
  }

  /// Whether target supports variable-length arrays.
  bool isVLASupported() const { return VLASupported; }

  /// Whether the target supports SEH __try.
  bool isSEHTrySupported() const {
    return getTriple().isOSWindows() &&
           (getTriple().getArch() == llvm::Triple::x86 ||
            getTriple().getArch() == llvm::Triple::x86_64 ||
            getTriple().getArch() == llvm::Triple::aarch64);
  }

  /// Return true if {|} are normal characters in the asm string.
  ///
  /// If this returns false (the default), then {abc|xyz} is syntax
  /// that says that when compiling for asm variant #0, "abc" should be
  /// generated, but when compiling for asm variant #1, "xyz" should be
  /// generated.
  bool hasNoAsmVariants() const {
    return NoAsmVariants;
  }

  /// Return the register number that __builtin_eh_return_regno would
  /// return with the specified argument.
  /// This corresponds with TargetLowering's getExceptionPointerRegister
  /// and getExceptionSelectorRegister in the backend.
  virtual int getEHDataRegisterNumber(unsigned RegNo) const {
    return -1;
  }

  /// Return the section to use for C++ static initialization functions.
  virtual const char *getStaticInitSectionSpecifier() const {
    return nullptr;
  }

  const LangASMap &getAddressSpaceMap() const { return *AddrSpaceMap; }

  /// Map from the address space field in builtin description strings to the
  /// language address space.
  virtual LangAS getOpenCLBuiltinAddressSpace(unsigned AS) const {
    return getLangASFromTargetAS(AS);
  }

  /// Map from the address space field in builtin description strings to the
  /// language address space.
  virtual LangAS getCUDABuiltinAddressSpace(unsigned AS) const {
    return getLangASFromTargetAS(AS);
  }

  /// Return an AST address space which can be used opportunistically
  /// for constant global memory. It must be possible to convert pointers into
  /// this address space to LangAS::Default. If no such address space exists,
  /// this may return None, and such optimizations will be disabled.
  virtual llvm::Optional<LangAS> getConstantAddressSpace() const {
    return LangAS::Default;
  }

  /// Retrieve the name of the platform as it is used in the
  /// availability attribute.
  StringRef getPlatformName() const { return PlatformName; }

  /// Retrieve the minimum desired version of the platform, to
  /// which the program should be compiled.
  VersionTuple getPlatformMinVersion() const { return PlatformMinVersion; }

  bool isBigEndian() const { return BigEndian; }
  bool isLittleEndian() const { return !BigEndian; }

  /// Gets the default calling convention for the given target and
  /// declaration context.
  virtual CallingConv getDefaultCallingConv() const {
    // Not all targets will specify an explicit calling convention that we can
    // express.  This will always do the right thing, even though it's not
    // an explicit calling convention.
    return CC_C;
  }

  enum CallingConvCheckResult {
    CCCR_OK,
    CCCR_Warning,
    CCCR_Ignore,
    CCCR_Error,
  };

  /// Determines whether a given calling convention is valid for the
  /// target. A calling convention can either be accepted, produce a warning
  /// and be substituted with the default calling convention, or (someday)
  /// produce an error (such as using thiscall on a non-instance function).
  virtual CallingConvCheckResult checkCallingConvention(CallingConv CC) const {
    switch (CC) {
      default:
        return CCCR_Warning;
      case CC_C:
        return CCCR_OK;
    }
  }

  enum CallingConvKind {
    CCK_Default,
    CCK_ClangABI4OrPS4,
    CCK_MicrosoftWin64
  };

  virtual CallingConvKind getCallingConvKind(bool ClangABICompat4) const;

  /// Controls if __builtin_longjmp / __builtin_setjmp can be lowered to
  /// llvm.eh.sjlj.longjmp / llvm.eh.sjlj.setjmp.
  virtual bool hasSjLjLowering() const {
    return false;
  }

  /// Check if the target supports CFProtection branch.
  virtual bool
  checkCFProtectionBranchSupported(DiagnosticsEngine &Diags) const;

  /// Check if the target supports CFProtection branch.
  virtual bool
  checkCFProtectionReturnSupported(DiagnosticsEngine &Diags) const;

  /// Whether target allows to overalign ABI-specified preferred alignment
  virtual bool allowsLargerPreferedTypeAlignment() const { return true; }

  /// Set supported OpenCL extensions and optional core features.
  virtual void setSupportedOpenCLOpts() {}

  /// Set supported OpenCL extensions as written on command line
  virtual void setOpenCLExtensionOpts() {
    for (const auto &Ext : getTargetOpts().OpenCLExtensionsAsWritten) {
      getTargetOpts().SupportedOpenCLOptions.support(Ext);
    }
  }

  /// Get supported OpenCL extensions and optional core features.
  OpenCLOptions &getSupportedOpenCLOpts() {
    return getTargetOpts().SupportedOpenCLOptions;
  }

  /// Get const supported OpenCL extensions and optional core features.
  const OpenCLOptions &getSupportedOpenCLOpts() const {
      return getTargetOpts().SupportedOpenCLOptions;
  }

  enum OpenCLTypeKind {
    OCLTK_Default,
    OCLTK_ClkEvent,
    OCLTK_Event,
    OCLTK_Image,
    OCLTK_Pipe,
    OCLTK_Queue,
    OCLTK_ReserveID,
    OCLTK_Sampler,
  };

  /// Get address space for OpenCL type.
  virtual LangAS getOpenCLTypeAddrSpace(OpenCLTypeKind TK) const;

  /// \returns Target specific vtbl ptr address space.
  virtual unsigned getVtblPtrAddressSpace() const {
    return 0;
  }

  /// \returns If a target requires an address within a target specific address
  /// space \p AddressSpace to be converted in order to be used, then return the
  /// corresponding target specific DWARF address space.
  ///
  /// \returns Otherwise return None and no conversion will be emitted in the
  /// DWARF.
  virtual Optional<unsigned> getDWARFAddressSpace(unsigned AddressSpace) const {
    return None;
  }

  /// \returns The version of the SDK which was used during the compilation if
  /// one was specified, or an empty version otherwise.
  const llvm::VersionTuple &getSDKVersion() const {
    return getTargetOpts().SDKVersion;
  }

  /// Check the target is valid after it is fully initialized.
  virtual bool validateTarget(DiagnosticsEngine &Diags) const {
    return true;
  }

  virtual void setAuxTarget(const TargetInfo *Aux) {}

protected:
  /// Copy type and layout related info.
  void copyAuxTarget(const TargetInfo *Aux);
  virtual uint64_t getPointerWidthV(unsigned AddrSpace) const {
    return PointerWidth;
  }
  virtual uint64_t getPointerAlignV(unsigned AddrSpace) const {
    return PointerAlign;
  }
  virtual enum IntType getPtrDiffTypeV(unsigned AddrSpace) const {
    return PtrDiffType;
  }
  virtual ArrayRef<const char *> getGCCRegNames() const = 0;
  virtual ArrayRef<GCCRegAlias> getGCCRegAliases() const = 0;
  virtual ArrayRef<AddlRegName> getGCCAddlRegNames() const {
    return None;
  }

 private:
  // Assert the values for the fractional and integral bits for each fixed point
  // type follow the restrictions given in clause 6.2.6.3 of N1169.
  void CheckFixedPointBits() const;
};

}  // end namespace clang

#endif