aboutsummaryrefslogtreecommitdiffstats
path: root/include/clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h
blob: 071e35085a5f93f6a0620e18186c56a7e7ef3849 (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
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
//==- MemRegion.h - Abstract memory regions for static analysis -*- 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
//
//===----------------------------------------------------------------------===//
//
//  This file defines MemRegion and its subclasses.  MemRegion defines a
//  partially-typed abstraction of memory useful for path-sensitive dataflow
//  analyses.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_MEMREGION_H
#define LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_MEMREGION_H

#include "clang/AST/ASTContext.h"
#include "clang/AST/CharUnits.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/DeclarationName.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExprObjC.h"
#include "clang/AST/Type.h"
#include "clang/Analysis/AnalysisDeclContext.h"
#include "clang/Basic/LLVM.h"
#include "clang/Basic/SourceLocation.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/SymExpr.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/FoldingSet.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/PointerIntPair.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/Casting.h"
#include <cassert>
#include <cstdint>
#include <limits>
#include <string>
#include <utility>

namespace clang {

class AnalysisDeclContext;
class CXXRecordDecl;
class Decl;
class LocationContext;
class StackFrameContext;

namespace ento {

class CodeTextRegion;
class MemRegion;
class MemRegionManager;
class MemSpaceRegion;
class SValBuilder;
class SymbolicRegion;
class VarRegion;

/// Represent a region's offset within the top level base region.
class RegionOffset {
  /// The base region.
  const MemRegion *R = nullptr;

  /// The bit offset within the base region. Can be negative.
  int64_t Offset;

public:
  // We're using a const instead of an enumeration due to the size required;
  // Visual Studio will only create enumerations of size int, not long long.
  static const int64_t Symbolic = std::numeric_limits<int64_t>::max();

  RegionOffset() = default;
  RegionOffset(const MemRegion *r, int64_t off) : R(r), Offset(off) {}

  const MemRegion *getRegion() const { return R; }

  bool hasSymbolicOffset() const { return Offset == Symbolic; }

  int64_t getOffset() const {
    assert(!hasSymbolicOffset());
    return Offset;
  }

  bool isValid() const { return R; }
};

//===----------------------------------------------------------------------===//
// Base region classes.
//===----------------------------------------------------------------------===//

/// MemRegion - The root abstract class for all memory regions.
class MemRegion : public llvm::FoldingSetNode {
public:
  enum Kind {
#define REGION(Id, Parent) Id ## Kind,
#define REGION_RANGE(Id, First, Last) BEGIN_##Id = First, END_##Id = Last,
#include "clang/StaticAnalyzer/Core/PathSensitive/Regions.def"
  };

private:
  const Kind kind;
  mutable Optional<RegionOffset> cachedOffset;

protected:
  MemRegion(Kind k) : kind(k) {}
  virtual ~MemRegion();

public:
  ASTContext &getContext() const;

  virtual void Profile(llvm::FoldingSetNodeID& ID) const = 0;

  virtual MemRegionManager* getMemRegionManager() const = 0;

  const MemSpaceRegion *getMemorySpace() const;

  const MemRegion *getBaseRegion() const;

  /// Recursively retrieve the region of the most derived class instance of
  /// regions of C++ base class instances.
  const MemRegion *getMostDerivedObjectRegion() const;

  /// Check if the region is a subregion of the given region.
  /// Each region is a subregion of itself.
  virtual bool isSubRegionOf(const MemRegion *R) const;

  const MemRegion *StripCasts(bool StripBaseAndDerivedCasts = true) const;

  /// If this is a symbolic region, returns the region. Otherwise,
  /// goes up the base chain looking for the first symbolic base region.
  const SymbolicRegion *getSymbolicBase() const;

  bool hasGlobalsOrParametersStorage() const;

  bool hasStackStorage() const;

  bool hasStackNonParametersStorage() const;

  bool hasStackParametersStorage() const;

  /// Compute the offset within the top level memory object.
  RegionOffset getAsOffset() const;

  /// Get a string representation of a region for debug use.
  std::string getString() const;

  virtual void dumpToStream(raw_ostream &os) const;

  void dump() const;

  /// Returns true if this region can be printed in a user-friendly way.
  virtual bool canPrintPretty() const;

  /// Print the region for use in diagnostics.
  virtual void printPretty(raw_ostream &os) const;

  /// Returns true if this region's textual representation can be used
  /// as part of a larger expression.
  virtual bool canPrintPrettyAsExpr() const;

  /// Print the region as expression.
  ///
  /// When this region represents a subexpression, the method is for printing
  /// an expression containing it.
  virtual void printPrettyAsExpr(raw_ostream &os) const;

  Kind getKind() const { return kind; }

  template<typename RegionTy> const RegionTy* getAs() const;

  virtual bool isBoundable() const { return false; }

  /// Get descriptive name for memory region. The name is obtained from
  /// the variable/field declaration retrieved from the memory region.
  /// Regions that point to an element of an array are returned as: "arr[0]".
  /// Regions that point to a struct are returned as: "st.var".
  //
  /// \param UseQuotes Set if the name should be quoted.
  ///
  /// \returns variable name for memory region
  std::string getDescriptiveName(bool UseQuotes = true) const;

  /// Retrieve source range from memory region. The range retrieval
  /// is based on the decl obtained from the memory region.
  /// For a VarRegion the range of the base region is returned.
  /// For a FieldRegion the range of the field is returned.
  /// If no declaration is found, an empty source range is returned.
  /// The client is responsible for checking if the returned range is valid.
  ///
  /// \returns source range for declaration retrieved from memory region
  SourceRange sourceRange() const;
};

/// MemSpaceRegion - A memory region that represents a "memory space";
///  for example, the set of global variables, the stack frame, etc.
class MemSpaceRegion : public MemRegion {
protected:
  MemRegionManager *Mgr;

  MemSpaceRegion(MemRegionManager *mgr, Kind k) : MemRegion(k), Mgr(mgr) {
    assert(classof(this));
    assert(mgr);
  }

  MemRegionManager* getMemRegionManager() const override { return Mgr; }

public:
  bool isBoundable() const override { return false; }

  void Profile(llvm::FoldingSetNodeID &ID) const override;

  static bool classof(const MemRegion *R) {
    Kind k = R->getKind();
    return k >= BEGIN_MEMSPACES && k <= END_MEMSPACES;
  }
};

/// CodeSpaceRegion - The memory space that holds the executable code of
/// functions and blocks.
class CodeSpaceRegion : public MemSpaceRegion {
  friend class MemRegionManager;

  CodeSpaceRegion(MemRegionManager *mgr)
      : MemSpaceRegion(mgr, CodeSpaceRegionKind) {}

public:
  void dumpToStream(raw_ostream &os) const override;

  static bool classof(const MemRegion *R) {
    return R->getKind() == CodeSpaceRegionKind;
  }
};

class GlobalsSpaceRegion : public MemSpaceRegion {
  virtual void anchor();

protected:
  GlobalsSpaceRegion(MemRegionManager *mgr, Kind k) : MemSpaceRegion(mgr, k) {
    assert(classof(this));
  }

public:
  static bool classof(const MemRegion *R) {
    Kind k = R->getKind();
    return k >= BEGIN_GLOBAL_MEMSPACES && k <= END_GLOBAL_MEMSPACES;
  }
};

/// The region of the static variables within the current CodeTextRegion
/// scope.
///
/// Currently, only the static locals are placed there, so we know that these
/// variables do not get invalidated by calls to other functions.
class StaticGlobalSpaceRegion : public GlobalsSpaceRegion {
  friend class MemRegionManager;

  const CodeTextRegion *CR;

  StaticGlobalSpaceRegion(MemRegionManager *mgr, const CodeTextRegion *cr)
      : GlobalsSpaceRegion(mgr, StaticGlobalSpaceRegionKind), CR(cr) {
    assert(cr);
  }

public:
  void Profile(llvm::FoldingSetNodeID &ID) const override;

  void dumpToStream(raw_ostream &os) const override;

  const CodeTextRegion *getCodeRegion() const { return CR; }

  static bool classof(const MemRegion *R) {
    return R->getKind() == StaticGlobalSpaceRegionKind;
  }
};

/// The region for all the non-static global variables.
///
/// This class is further split into subclasses for efficient implementation of
/// invalidating a set of related global values as is done in
/// RegionStoreManager::invalidateRegions (instead of finding all the dependent
/// globals, we invalidate the whole parent region).
class NonStaticGlobalSpaceRegion : public GlobalsSpaceRegion {
  void anchor() override;

protected:
  NonStaticGlobalSpaceRegion(MemRegionManager *mgr, Kind k)
      : GlobalsSpaceRegion(mgr, k) {
    assert(classof(this));
  }

public:
  static bool classof(const MemRegion *R) {
    Kind k = R->getKind();
    return k >= BEGIN_NON_STATIC_GLOBAL_MEMSPACES &&
           k <= END_NON_STATIC_GLOBAL_MEMSPACES;
  }
};

/// The region containing globals which are defined in system/external
/// headers and are considered modifiable by system calls (ex: errno).
class GlobalSystemSpaceRegion : public NonStaticGlobalSpaceRegion {
  friend class MemRegionManager;

  GlobalSystemSpaceRegion(MemRegionManager *mgr)
      : NonStaticGlobalSpaceRegion(mgr, GlobalSystemSpaceRegionKind) {}

public:
  void dumpToStream(raw_ostream &os) const override;

  static bool classof(const MemRegion *R) {
    return R->getKind() == GlobalSystemSpaceRegionKind;
  }
};

/// The region containing globals which are considered not to be modified
/// or point to data which could be modified as a result of a function call
/// (system or internal). Ex: Const global scalars would be modeled as part of
/// this region. This region also includes most system globals since they have
/// low chance of being modified.
class GlobalImmutableSpaceRegion : public NonStaticGlobalSpaceRegion {
  friend class MemRegionManager;

  GlobalImmutableSpaceRegion(MemRegionManager *mgr)
      : NonStaticGlobalSpaceRegion(mgr, GlobalImmutableSpaceRegionKind) {}

public:
  void dumpToStream(raw_ostream &os) const override;

  static bool classof(const MemRegion *R) {
    return R->getKind() == GlobalImmutableSpaceRegionKind;
  }
};

/// The region containing globals which can be modified by calls to
/// "internally" defined functions - (for now just) functions other then system
/// calls.
class GlobalInternalSpaceRegion : public NonStaticGlobalSpaceRegion {
  friend class MemRegionManager;

  GlobalInternalSpaceRegion(MemRegionManager *mgr)
      : NonStaticGlobalSpaceRegion(mgr, GlobalInternalSpaceRegionKind) {}

public:
  void dumpToStream(raw_ostream &os) const override;

  static bool classof(const MemRegion *R) {
    return R->getKind() == GlobalInternalSpaceRegionKind;
  }
};

class HeapSpaceRegion : public MemSpaceRegion {
  friend class MemRegionManager;

  HeapSpaceRegion(MemRegionManager *mgr)
      : MemSpaceRegion(mgr, HeapSpaceRegionKind) {}

public:
  void dumpToStream(raw_ostream &os) const override;

  static bool classof(const MemRegion *R) {
    return R->getKind() == HeapSpaceRegionKind;
  }
};

class UnknownSpaceRegion : public MemSpaceRegion {
  friend class MemRegionManager;

  UnknownSpaceRegion(MemRegionManager *mgr)
      : MemSpaceRegion(mgr, UnknownSpaceRegionKind) {}

public:
  void dumpToStream(raw_ostream &os) const override;

  static bool classof(const MemRegion *R) {
    return R->getKind() == UnknownSpaceRegionKind;
  }
};

class StackSpaceRegion : public MemSpaceRegion {
  virtual void anchor();

  const StackFrameContext *SFC;

protected:
  StackSpaceRegion(MemRegionManager *mgr, Kind k, const StackFrameContext *sfc)
      : MemSpaceRegion(mgr, k), SFC(sfc) {
    assert(classof(this));
    assert(sfc);
  }

public:
  const StackFrameContext *getStackFrame() const { return SFC; }

  void Profile(llvm::FoldingSetNodeID &ID) const override;

  static bool classof(const MemRegion *R) {
    Kind k = R->getKind();
    return k >= BEGIN_STACK_MEMSPACES && k <= END_STACK_MEMSPACES;
  }
};

class StackLocalsSpaceRegion : public StackSpaceRegion {
  friend class MemRegionManager;

  StackLocalsSpaceRegion(MemRegionManager *mgr, const StackFrameContext *sfc)
      : StackSpaceRegion(mgr, StackLocalsSpaceRegionKind, sfc) {}

public:
  void dumpToStream(raw_ostream &os) const override;

  static bool classof(const MemRegion *R) {
    return R->getKind() == StackLocalsSpaceRegionKind;
  }
};

class StackArgumentsSpaceRegion : public StackSpaceRegion {
private:
  friend class MemRegionManager;

  StackArgumentsSpaceRegion(MemRegionManager *mgr, const StackFrameContext *sfc)
      : StackSpaceRegion(mgr, StackArgumentsSpaceRegionKind, sfc) {}

public:
  void dumpToStream(raw_ostream &os) const override;

  static bool classof(const MemRegion *R) {
    return R->getKind() == StackArgumentsSpaceRegionKind;
  }
};

/// SubRegion - A region that subsets another larger region.  Most regions
///  are subclasses of SubRegion.
class SubRegion : public MemRegion {
  virtual void anchor();

protected:
  const MemRegion* superRegion;

  SubRegion(const MemRegion *sReg, Kind k) : MemRegion(k), superRegion(sReg) {
    assert(classof(this));
    assert(sReg);
  }

public:
  const MemRegion* getSuperRegion() const {
    return superRegion;
  }

  /// getExtent - Returns the size of the region in bytes.
  virtual DefinedOrUnknownSVal getExtent(SValBuilder &svalBuilder) const {
    return UnknownVal();
  }

  MemRegionManager* getMemRegionManager() const override;

  bool isSubRegionOf(const MemRegion* R) const override;

  static bool classof(const MemRegion* R) {
    return R->getKind() > END_MEMSPACES;
  }
};

//===----------------------------------------------------------------------===//
// MemRegion subclasses.
//===----------------------------------------------------------------------===//

/// AllocaRegion - A region that represents an untyped blob of bytes created
///  by a call to 'alloca'.
class AllocaRegion : public SubRegion {
  friend class MemRegionManager;

  // Block counter. Used to distinguish different pieces of memory allocated by
  // alloca at the same call site.
  unsigned Cnt;

  const Expr *Ex;

  AllocaRegion(const Expr *ex, unsigned cnt, const MemSpaceRegion *superRegion)
      : SubRegion(superRegion, AllocaRegionKind), Cnt(cnt), Ex(ex) {
    assert(Ex);
  }

  static void ProfileRegion(llvm::FoldingSetNodeID& ID, const Expr *Ex,
                            unsigned Cnt, const MemRegion *superRegion);

public:
  const Expr *getExpr() const { return Ex; }

  bool isBoundable() const override { return true; }

  DefinedOrUnknownSVal getExtent(SValBuilder &svalBuilder) const override;

  void Profile(llvm::FoldingSetNodeID& ID) const override;

  void dumpToStream(raw_ostream &os) const override;

  static bool classof(const MemRegion* R) {
    return R->getKind() == AllocaRegionKind;
  }
};

/// TypedRegion - An abstract class representing regions that are typed.
class TypedRegion : public SubRegion {
  void anchor() override;

protected:
  TypedRegion(const MemRegion *sReg, Kind k) : SubRegion(sReg, k) {
    assert(classof(this));
  }

public:
  virtual QualType getLocationType() const = 0;

  QualType getDesugaredLocationType(ASTContext &Context) const {
    return getLocationType().getDesugaredType(Context);
  }

  bool isBoundable() const override { return true; }

  static bool classof(const MemRegion* R) {
    unsigned k = R->getKind();
    return k >= BEGIN_TYPED_REGIONS && k <= END_TYPED_REGIONS;
  }
};

/// TypedValueRegion - An abstract class representing regions having a typed value.
class TypedValueRegion : public TypedRegion {
  void anchor() override;

protected:
  TypedValueRegion(const MemRegion* sReg, Kind k) : TypedRegion(sReg, k) {
    assert(classof(this));
  }

public:
  virtual QualType getValueType() const = 0;

  QualType getLocationType() const override {
    // FIXME: We can possibly optimize this later to cache this value.
    QualType T = getValueType();
    ASTContext &ctx = getContext();
    if (T->getAs<ObjCObjectType>())
      return ctx.getObjCObjectPointerType(T);
    return ctx.getPointerType(getValueType());
  }

  QualType getDesugaredValueType(ASTContext &Context) const {
    QualType T = getValueType();
    return T.getTypePtrOrNull() ? T.getDesugaredType(Context) : T;
  }

  DefinedOrUnknownSVal getExtent(SValBuilder &svalBuilder) const override;

  static bool classof(const MemRegion* R) {
    unsigned k = R->getKind();
    return k >= BEGIN_TYPED_VALUE_REGIONS && k <= END_TYPED_VALUE_REGIONS;
  }
};

class CodeTextRegion : public TypedRegion {
  void anchor() override;

protected:
  CodeTextRegion(const MemSpaceRegion *sreg, Kind k) : TypedRegion(sreg, k) {
    assert(classof(this));
  }

public:
  bool isBoundable() const override { return false; }

  static bool classof(const MemRegion* R) {
    Kind k = R->getKind();
    return k >= BEGIN_CODE_TEXT_REGIONS && k <= END_CODE_TEXT_REGIONS;
  }
};

/// FunctionCodeRegion - A region that represents code texts of function.
class FunctionCodeRegion : public CodeTextRegion {
  friend class MemRegionManager;

  const NamedDecl *FD;

  FunctionCodeRegion(const NamedDecl *fd, const CodeSpaceRegion* sreg)
      : CodeTextRegion(sreg, FunctionCodeRegionKind), FD(fd) {
    assert(isa<ObjCMethodDecl>(fd) || isa<FunctionDecl>(fd));
  }

  static void ProfileRegion(llvm::FoldingSetNodeID& ID, const NamedDecl *FD,
                            const MemRegion*);

public:
  QualType getLocationType() const override {
    const ASTContext &Ctx = getContext();
    if (const auto *D = dyn_cast<FunctionDecl>(FD)) {
      return Ctx.getPointerType(D->getType());
    }

    assert(isa<ObjCMethodDecl>(FD));
    assert(false && "Getting the type of ObjCMethod is not supported yet");

    // TODO: We might want to return a different type here (ex: id (*ty)(...))
    //       depending on how it is used.
    return {};
  }

  const NamedDecl *getDecl() const {
    return FD;
  }

  void dumpToStream(raw_ostream &os) const override;

  void Profile(llvm::FoldingSetNodeID& ID) const override;

  static bool classof(const MemRegion* R) {
    return R->getKind() == FunctionCodeRegionKind;
  }
};

/// BlockCodeRegion - A region that represents code texts of blocks (closures).
///  Blocks are represented with two kinds of regions.  BlockCodeRegions
///  represent the "code", while BlockDataRegions represent instances of blocks,
///  which correspond to "code+data".  The distinction is important, because
///  like a closure a block captures the values of externally referenced
///  variables.
class BlockCodeRegion : public CodeTextRegion {
  friend class MemRegionManager;

  const BlockDecl *BD;
  AnalysisDeclContext *AC;
  CanQualType locTy;

  BlockCodeRegion(const BlockDecl *bd, CanQualType lTy,
                  AnalysisDeclContext *ac, const CodeSpaceRegion* sreg)
      : CodeTextRegion(sreg, BlockCodeRegionKind), BD(bd), AC(ac), locTy(lTy) {
    assert(bd);
    assert(ac);
    assert(lTy->getTypePtr()->isBlockPointerType());
  }

  static void ProfileRegion(llvm::FoldingSetNodeID& ID, const BlockDecl *BD,
                            CanQualType, const AnalysisDeclContext*,
                            const MemRegion*);

public:
  QualType getLocationType() const override {
    return locTy;
  }

  const BlockDecl *getDecl() const {
    return BD;
  }

  AnalysisDeclContext *getAnalysisDeclContext() const { return AC; }

  void dumpToStream(raw_ostream &os) const override;

  void Profile(llvm::FoldingSetNodeID& ID) const override;

  static bool classof(const MemRegion* R) {
    return R->getKind() == BlockCodeRegionKind;
  }
};

/// BlockDataRegion - A region that represents a block instance.
///  Blocks are represented with two kinds of regions.  BlockCodeRegions
///  represent the "code", while BlockDataRegions represent instances of blocks,
///  which correspond to "code+data".  The distinction is important, because
///  like a closure a block captures the values of externally referenced
///  variables.
class BlockDataRegion : public TypedRegion {
  friend class MemRegionManager;

  const BlockCodeRegion *BC;
  const LocationContext *LC; // Can be null
  unsigned BlockCount;
  void *ReferencedVars = nullptr;
  void *OriginalVars = nullptr;

  BlockDataRegion(const BlockCodeRegion *bc, const LocationContext *lc,
                  unsigned count, const MemSpaceRegion *sreg)
      : TypedRegion(sreg, BlockDataRegionKind), BC(bc), LC(lc),
        BlockCount(count) {
    assert(bc);
    assert(lc);
    assert(isa<GlobalImmutableSpaceRegion>(sreg) ||
           isa<StackLocalsSpaceRegion>(sreg) ||
           isa<UnknownSpaceRegion>(sreg));
  }

  static void ProfileRegion(llvm::FoldingSetNodeID&, const BlockCodeRegion *,
                            const LocationContext *, unsigned,
                            const MemRegion *);

public:
  const BlockCodeRegion *getCodeRegion() const { return BC; }

  const BlockDecl *getDecl() const { return BC->getDecl(); }

  QualType getLocationType() const override { return BC->getLocationType(); }

  class referenced_vars_iterator {
    const MemRegion * const *R;
    const MemRegion * const *OriginalR;

  public:
    explicit referenced_vars_iterator(const MemRegion * const *r,
                                      const MemRegion * const *originalR)
        : R(r), OriginalR(originalR) {}

    const VarRegion *getCapturedRegion() const {
      return cast<VarRegion>(*R);
    }

    const VarRegion *getOriginalRegion() const {
      return cast<VarRegion>(*OriginalR);
    }

    bool operator==(const referenced_vars_iterator &I) const {
      assert((R == nullptr) == (I.R == nullptr));
      return I.R == R;
    }

    bool operator!=(const referenced_vars_iterator &I) const {
      assert((R == nullptr) == (I.R == nullptr));
      return I.R != R;
    }

    referenced_vars_iterator &operator++() {
      ++R;
      ++OriginalR;
      return *this;
    }
  };

  /// Return the original region for a captured region, if
  /// one exists.
  const VarRegion *getOriginalRegion(const VarRegion *VR) const;

  referenced_vars_iterator referenced_vars_begin() const;
  referenced_vars_iterator referenced_vars_end() const;

  void dumpToStream(raw_ostream &os) const override;

  void Profile(llvm::FoldingSetNodeID& ID) const override;

  static bool classof(const MemRegion* R) {
    return R->getKind() == BlockDataRegionKind;
  }

private:
  void LazyInitializeReferencedVars();
  std::pair<const VarRegion *, const VarRegion *>
  getCaptureRegions(const VarDecl *VD);
};

/// SymbolicRegion - A special, "non-concrete" region. Unlike other region
///  classes, SymbolicRegion represents a region that serves as an alias for
///  either a real region, a NULL pointer, etc.  It essentially is used to
///  map the concept of symbolic values into the domain of regions.  Symbolic
///  regions do not need to be typed.
class SymbolicRegion : public SubRegion {
  friend class MemRegionManager;

  const SymbolRef sym;

  SymbolicRegion(const SymbolRef s, const MemSpaceRegion *sreg)
      : SubRegion(sreg, SymbolicRegionKind), sym(s) {
    // Because pointer arithmetic is represented by ElementRegion layers,
    // the base symbol here should not contain any arithmetic.
    assert(s && isa<SymbolData>(s));
    assert(s->getType()->isAnyPointerType() ||
           s->getType()->isReferenceType() ||
           s->getType()->isBlockPointerType());
    assert(isa<UnknownSpaceRegion>(sreg) || isa<HeapSpaceRegion>(sreg));
  }

public:
  SymbolRef getSymbol() const { return sym; }

  bool isBoundable() const override { return true; }

  DefinedOrUnknownSVal getExtent(SValBuilder &svalBuilder) const override;

  void Profile(llvm::FoldingSetNodeID& ID) const override;

  static void ProfileRegion(llvm::FoldingSetNodeID& ID,
                            SymbolRef sym,
                            const MemRegion* superRegion);

  void dumpToStream(raw_ostream &os) const override;

  static bool classof(const MemRegion* R) {
    return R->getKind() == SymbolicRegionKind;
  }
};

/// StringRegion - Region associated with a StringLiteral.
class StringRegion : public TypedValueRegion {
  friend class MemRegionManager;

  const StringLiteral *Str;

  StringRegion(const StringLiteral *str, const GlobalInternalSpaceRegion *sreg)
      : TypedValueRegion(sreg, StringRegionKind), Str(str) {
    assert(str);
  }

  static void ProfileRegion(llvm::FoldingSetNodeID &ID,
                            const StringLiteral *Str,
                            const MemRegion *superRegion);

public:
  const StringLiteral *getStringLiteral() const { return Str; }

  QualType getValueType() const override { return Str->getType(); }

  DefinedOrUnknownSVal getExtent(SValBuilder &svalBuilder) const override;

  bool isBoundable() const override { return false; }

  void Profile(llvm::FoldingSetNodeID& ID) const override {
    ProfileRegion(ID, Str, superRegion);
  }

  void dumpToStream(raw_ostream &os) const override;

  static bool classof(const MemRegion* R) {
    return R->getKind() == StringRegionKind;
  }
};

/// The region associated with an ObjCStringLiteral.
class ObjCStringRegion : public TypedValueRegion {
  friend class MemRegionManager;

  const ObjCStringLiteral *Str;

  ObjCStringRegion(const ObjCStringLiteral *str,
                   const GlobalInternalSpaceRegion *sreg)
      : TypedValueRegion(sreg, ObjCStringRegionKind), Str(str) {
    assert(str);
  }

  static void ProfileRegion(llvm::FoldingSetNodeID &ID,
                            const ObjCStringLiteral *Str,
                            const MemRegion *superRegion);

public:
  const ObjCStringLiteral *getObjCStringLiteral() const { return Str; }

  QualType getValueType() const override { return Str->getType(); }

  bool isBoundable() const override { return false; }

  void Profile(llvm::FoldingSetNodeID& ID) const override {
    ProfileRegion(ID, Str, superRegion);
  }

  void dumpToStream(raw_ostream &os) const override;

  static bool classof(const MemRegion* R) {
    return R->getKind() == ObjCStringRegionKind;
  }
};

/// CompoundLiteralRegion - A memory region representing a compound literal.
///   Compound literals are essentially temporaries that are stack allocated
///   or in the global constant pool.
class CompoundLiteralRegion : public TypedValueRegion {
  friend class MemRegionManager;

  const CompoundLiteralExpr *CL;

  CompoundLiteralRegion(const CompoundLiteralExpr *cl,
                        const MemSpaceRegion *sReg)
      : TypedValueRegion(sReg, CompoundLiteralRegionKind), CL(cl) {
    assert(cl);
    assert(isa<GlobalInternalSpaceRegion>(sReg) ||
           isa<StackLocalsSpaceRegion>(sReg));
  }

  static void ProfileRegion(llvm::FoldingSetNodeID& ID,
                            const CompoundLiteralExpr *CL,
                            const MemRegion* superRegion);

public:
  QualType getValueType() const override { return CL->getType(); }

  bool isBoundable() const override { return !CL->isFileScope(); }

  void Profile(llvm::FoldingSetNodeID& ID) const override;

  void dumpToStream(raw_ostream &os) const override;

  const CompoundLiteralExpr *getLiteralExpr() const { return CL; }

  static bool classof(const MemRegion* R) {
    return R->getKind() == CompoundLiteralRegionKind;
  }
};

class DeclRegion : public TypedValueRegion {
protected:
  const ValueDecl *D;

  DeclRegion(const ValueDecl *d, const MemRegion *sReg, Kind k)
      : TypedValueRegion(sReg, k), D(d) {
    assert(classof(this));
    assert(d && d->isCanonicalDecl());
  }

  static void ProfileRegion(llvm::FoldingSetNodeID& ID, const Decl *D,
                      const MemRegion* superRegion, Kind k);

public:
  const ValueDecl *getDecl() const { return D; }
  void Profile(llvm::FoldingSetNodeID& ID) const override;

  static bool classof(const MemRegion* R) {
    unsigned k = R->getKind();
    return k >= BEGIN_DECL_REGIONS && k <= END_DECL_REGIONS;
  }
};

class VarRegion : public DeclRegion {
  friend class MemRegionManager;

  // Constructors and private methods.
  VarRegion(const VarDecl *vd, const MemRegion *sReg)
      : DeclRegion(vd, sReg, VarRegionKind) {
    // VarRegion appears in unknown space when it's a block variable as seen
    // from a block using it, when this block is analyzed at top-level.
    // Other block variables appear within block data regions,
    // which, unlike everything else on this list, are not memory spaces.
    assert(isa<GlobalsSpaceRegion>(sReg) || isa<StackSpaceRegion>(sReg) ||
           isa<BlockDataRegion>(sReg) || isa<UnknownSpaceRegion>(sReg));
  }

  static void ProfileRegion(llvm::FoldingSetNodeID& ID, const VarDecl *VD,
                            const MemRegion *superRegion) {
    DeclRegion::ProfileRegion(ID, VD, superRegion, VarRegionKind);
  }

public:
  void Profile(llvm::FoldingSetNodeID& ID) const override;

  const VarDecl *getDecl() const { return cast<VarDecl>(D); }

  const StackFrameContext *getStackFrame() const;

  QualType getValueType() const override {
    // FIXME: We can cache this if needed.
    return getDecl()->getType();
  }

  void dumpToStream(raw_ostream &os) const override;

  bool canPrintPrettyAsExpr() const override;

  void printPrettyAsExpr(raw_ostream &os) const override;

  static bool classof(const MemRegion* R) {
    return R->getKind() == VarRegionKind;
  }
};

/// CXXThisRegion - Represents the region for the implicit 'this' parameter
///  in a call to a C++ method.  This region doesn't represent the object
///  referred to by 'this', but rather 'this' itself.
class CXXThisRegion : public TypedValueRegion {
  friend class MemRegionManager;

  CXXThisRegion(const PointerType *thisPointerTy,
                const StackArgumentsSpaceRegion *sReg)
      : TypedValueRegion(sReg, CXXThisRegionKind),
        ThisPointerTy(thisPointerTy) {
    assert(ThisPointerTy->getPointeeType()->getAsCXXRecordDecl() &&
           "Invalid region type!");
  }

  static void ProfileRegion(llvm::FoldingSetNodeID &ID,
                            const PointerType *PT,
                            const MemRegion *sReg);

public:
  void Profile(llvm::FoldingSetNodeID &ID) const override;

  QualType getValueType() const override {
    return QualType(ThisPointerTy, 0);
  }

  void dumpToStream(raw_ostream &os) const override;

  static bool classof(const MemRegion* R) {
    return R->getKind() == CXXThisRegionKind;
  }

private:
  const PointerType *ThisPointerTy;
};

class FieldRegion : public DeclRegion {
  friend class MemRegionManager;

  FieldRegion(const FieldDecl *fd, const SubRegion* sReg)
      : DeclRegion(fd, sReg, FieldRegionKind) {}

  static void ProfileRegion(llvm::FoldingSetNodeID& ID, const FieldDecl *FD,
                            const MemRegion* superRegion) {
    DeclRegion::ProfileRegion(ID, FD, superRegion, FieldRegionKind);
  }

public:
  const FieldDecl *getDecl() const { return cast<FieldDecl>(D); }

  QualType getValueType() const override {
    // FIXME: We can cache this if needed.
    return getDecl()->getType();
  }

  DefinedOrUnknownSVal getExtent(SValBuilder &svalBuilder) const override;

  void dumpToStream(raw_ostream &os) const override;

  bool canPrintPretty() const override;
  void printPretty(raw_ostream &os) const override;
  bool canPrintPrettyAsExpr() const override;
  void printPrettyAsExpr(raw_ostream &os) const override;

  static bool classof(const MemRegion* R) {
    return R->getKind() == FieldRegionKind;
  }
};

class ObjCIvarRegion : public DeclRegion {
  friend class MemRegionManager;

  ObjCIvarRegion(const ObjCIvarDecl *ivd, const SubRegion *sReg);

  static void ProfileRegion(llvm::FoldingSetNodeID& ID, const ObjCIvarDecl *ivd,
                            const MemRegion* superRegion);

public:
  const ObjCIvarDecl *getDecl() const;
  QualType getValueType() const override;

  bool canPrintPrettyAsExpr() const override;
  void printPrettyAsExpr(raw_ostream &os) const override;

  void dumpToStream(raw_ostream &os) const override;

  static bool classof(const MemRegion* R) {
    return R->getKind() == ObjCIvarRegionKind;
  }
};

//===----------------------------------------------------------------------===//
// Auxiliary data classes for use with MemRegions.
//===----------------------------------------------------------------------===//

class RegionRawOffset {
  friend class ElementRegion;

  const MemRegion *Region;
  CharUnits Offset;

  RegionRawOffset(const MemRegion* reg, CharUnits offset = CharUnits::Zero())
      : Region(reg), Offset(offset) {}

public:
  // FIXME: Eventually support symbolic offsets.
  CharUnits getOffset() const { return Offset; }
  const MemRegion *getRegion() const { return Region; }

  void dumpToStream(raw_ostream &os) const;
  void dump() const;
};

/// ElementRegion is used to represent both array elements and casts.
class ElementRegion : public TypedValueRegion {
  friend class MemRegionManager;

  QualType ElementType;
  NonLoc Index;

  ElementRegion(QualType elementType, NonLoc Idx, const SubRegion *sReg)
      : TypedValueRegion(sReg, ElementRegionKind), ElementType(elementType),
        Index(Idx) {
    assert((!Idx.getAs<nonloc::ConcreteInt>() ||
            Idx.castAs<nonloc::ConcreteInt>().getValue().isSigned()) &&
           "The index must be signed");
    assert(!elementType.isNull() && !elementType->isVoidType() &&
           "Invalid region type!");
  }

  static void ProfileRegion(llvm::FoldingSetNodeID& ID, QualType elementType,
                            SVal Idx, const MemRegion* superRegion);

public:
  NonLoc getIndex() const { return Index; }

  QualType getValueType() const override { return ElementType; }

  QualType getElementType() const { return ElementType; }

  /// Compute the offset within the array. The array might also be a subobject.
  RegionRawOffset getAsArrayOffset() const;

  void dumpToStream(raw_ostream &os) const override;

  void Profile(llvm::FoldingSetNodeID& ID) const override;

  static bool classof(const MemRegion* R) {
    return R->getKind() == ElementRegionKind;
  }
};

// C++ temporary object associated with an expression.
class CXXTempObjectRegion : public TypedValueRegion {
  friend class MemRegionManager;

  Expr const *Ex;

  CXXTempObjectRegion(Expr const *E, MemSpaceRegion const *sReg)
      : TypedValueRegion(sReg, CXXTempObjectRegionKind), Ex(E) {
    assert(E);
    assert(isa<StackLocalsSpaceRegion>(sReg) ||
           isa<GlobalInternalSpaceRegion>(sReg));
  }

  static void ProfileRegion(llvm::FoldingSetNodeID &ID,
                            Expr const *E, const MemRegion *sReg);

public:
  const Expr *getExpr() const { return Ex; }

  QualType getValueType() const override { return Ex->getType(); }

  void dumpToStream(raw_ostream &os) const override;

  void Profile(llvm::FoldingSetNodeID &ID) const override;

  static bool classof(const MemRegion* R) {
    return R->getKind() == CXXTempObjectRegionKind;
  }
};

// CXXBaseObjectRegion represents a base object within a C++ object. It is
// identified by the base class declaration and the region of its parent object.
class CXXBaseObjectRegion : public TypedValueRegion {
  friend class MemRegionManager;

  llvm::PointerIntPair<const CXXRecordDecl *, 1, bool> Data;

  CXXBaseObjectRegion(const CXXRecordDecl *RD, bool IsVirtual,
                      const SubRegion *SReg)
      : TypedValueRegion(SReg, CXXBaseObjectRegionKind), Data(RD, IsVirtual) {
    assert(RD);
  }

  static void ProfileRegion(llvm::FoldingSetNodeID &ID, const CXXRecordDecl *RD,
                            bool IsVirtual, const MemRegion *SReg);

public:
  const CXXRecordDecl *getDecl() const { return Data.getPointer(); }
  bool isVirtual() const { return Data.getInt(); }

  QualType getValueType() const override;

  void dumpToStream(raw_ostream &os) const override;

  void Profile(llvm::FoldingSetNodeID &ID) const override;

  bool canPrintPrettyAsExpr() const override;

  void printPrettyAsExpr(raw_ostream &os) const override;

  static bool classof(const MemRegion *region) {
    return region->getKind() == CXXBaseObjectRegionKind;
  }
};

// CXXDerivedObjectRegion represents a derived-class object that surrounds
// a C++ object. It is identified by the derived class declaration and the
// region of its parent object. It is a bit counter-intuitive (but not otherwise
// unseen) that this region represents a larger segment of memory that its
// super-region.
class CXXDerivedObjectRegion : public TypedValueRegion {
  friend class MemRegionManager;

  const CXXRecordDecl *DerivedD;

  CXXDerivedObjectRegion(const CXXRecordDecl *DerivedD, const SubRegion *SReg)
      : TypedValueRegion(SReg, CXXDerivedObjectRegionKind), DerivedD(DerivedD) {
    assert(DerivedD);
    // In case of a concrete region, it should always be possible to model
    // the base-to-derived cast by undoing a previous derived-to-base cast,
    // otherwise the cast is most likely ill-formed.
    assert(SReg->getSymbolicBase() &&
           "Should have unwrapped a base region instead!");
  }

  static void ProfileRegion(llvm::FoldingSetNodeID &ID, const CXXRecordDecl *RD,
                            const MemRegion *SReg);

public:
  const CXXRecordDecl *getDecl() const { return DerivedD; }

  QualType getValueType() const override;

  void dumpToStream(raw_ostream &os) const override;

  void Profile(llvm::FoldingSetNodeID &ID) const override;

  bool canPrintPrettyAsExpr() const override;

  void printPrettyAsExpr(raw_ostream &os) const override;

  static bool classof(const MemRegion *region) {
    return region->getKind() == CXXDerivedObjectRegionKind;
  }
};

template<typename RegionTy>
const RegionTy* MemRegion::getAs() const {
  if (const auto *RT = dyn_cast<RegionTy>(this))
    return RT;

  return nullptr;
}

//===----------------------------------------------------------------------===//
// MemRegionManager - Factory object for creating regions.
//===----------------------------------------------------------------------===//

class MemRegionManager {
  ASTContext &C;
  llvm::BumpPtrAllocator& A;
  llvm::FoldingSet<MemRegion> Regions;

  GlobalInternalSpaceRegion *InternalGlobals = nullptr;
  GlobalSystemSpaceRegion *SystemGlobals = nullptr;
  GlobalImmutableSpaceRegion *ImmutableGlobals = nullptr;

  llvm::DenseMap<const StackFrameContext *, StackLocalsSpaceRegion *>
    StackLocalsSpaceRegions;
  llvm::DenseMap<const StackFrameContext *, StackArgumentsSpaceRegion *>
    StackArgumentsSpaceRegions;
  llvm::DenseMap<const CodeTextRegion *, StaticGlobalSpaceRegion *>
    StaticsGlobalSpaceRegions;

  HeapSpaceRegion *heap = nullptr;
  UnknownSpaceRegion *unknown = nullptr;
  CodeSpaceRegion *code = nullptr;

public:
  MemRegionManager(ASTContext &c, llvm::BumpPtrAllocator &a) : C(c), A(a) {}
  ~MemRegionManager();

  ASTContext &getContext() { return C; }

  llvm::BumpPtrAllocator &getAllocator() { return A; }

  /// getStackLocalsRegion - Retrieve the memory region associated with the
  ///  specified stack frame.
  const StackLocalsSpaceRegion *
  getStackLocalsRegion(const StackFrameContext *STC);

  /// getStackArgumentsRegion - Retrieve the memory region associated with
  ///  function/method arguments of the specified stack frame.
  const StackArgumentsSpaceRegion *
  getStackArgumentsRegion(const StackFrameContext *STC);

  /// getGlobalsRegion - Retrieve the memory region associated with
  ///  global variables.
  const GlobalsSpaceRegion *getGlobalsRegion(
      MemRegion::Kind K = MemRegion::GlobalInternalSpaceRegionKind,
      const CodeTextRegion *R = nullptr);

  /// getHeapRegion - Retrieve the memory region associated with the
  ///  generic "heap".
  const HeapSpaceRegion *getHeapRegion();

  /// getUnknownRegion - Retrieve the memory region associated with unknown
  /// memory space.
  const UnknownSpaceRegion *getUnknownRegion();

  const CodeSpaceRegion *getCodeRegion();

  /// getAllocaRegion - Retrieve a region associated with a call to alloca().
  const AllocaRegion *getAllocaRegion(const Expr *Ex, unsigned Cnt,
                                      const LocationContext *LC);

  /// getCompoundLiteralRegion - Retrieve the region associated with a
  ///  given CompoundLiteral.
  const CompoundLiteralRegion*
  getCompoundLiteralRegion(const CompoundLiteralExpr *CL,
                           const LocationContext *LC);

  /// getCXXThisRegion - Retrieve the [artificial] region associated with the
  ///  parameter 'this'.
  const CXXThisRegion *getCXXThisRegion(QualType thisPointerTy,
                                        const LocationContext *LC);

  /// Retrieve or create a "symbolic" memory region.
  const SymbolicRegion* getSymbolicRegion(SymbolRef Sym);

  /// Return a unique symbolic region belonging to heap memory space.
  const SymbolicRegion *getSymbolicHeapRegion(SymbolRef sym);

  const StringRegion *getStringRegion(const StringLiteral *Str);

  const ObjCStringRegion *getObjCStringRegion(const ObjCStringLiteral *Str);

  /// getVarRegion - Retrieve or create the memory region associated with
  ///  a specified VarDecl and LocationContext.
  const VarRegion* getVarRegion(const VarDecl *D, const LocationContext *LC);

  /// getVarRegion - Retrieve or create the memory region associated with
  ///  a specified VarDecl and super region.
  const VarRegion *getVarRegion(const VarDecl *D, const MemRegion *superR);

  /// getElementRegion - Retrieve the memory region associated with the
  ///  associated element type, index, and super region.
  const ElementRegion *getElementRegion(QualType elementType, NonLoc Idx,
                                        const SubRegion *superRegion,
                                        ASTContext &Ctx);

  const ElementRegion *getElementRegionWithSuper(const ElementRegion *ER,
                                                 const SubRegion *superRegion) {
    return getElementRegion(ER->getElementType(), ER->getIndex(),
                            superRegion, ER->getContext());
  }

  /// getFieldRegion - Retrieve or create the memory region associated with
  ///  a specified FieldDecl.  'superRegion' corresponds to the containing
  ///  memory region (which typically represents the memory representing
  ///  a structure or class).
  const FieldRegion *getFieldRegion(const FieldDecl *fd,
                                    const SubRegion* superRegion);

  const FieldRegion *getFieldRegionWithSuper(const FieldRegion *FR,
                                             const SubRegion *superRegion) {
    return getFieldRegion(FR->getDecl(), superRegion);
  }

  /// getObjCIvarRegion - Retrieve or create the memory region associated with
  ///   a specified Objective-c instance variable.  'superRegion' corresponds
  ///   to the containing region (which typically represents the Objective-C
  ///   object).
  const ObjCIvarRegion *getObjCIvarRegion(const ObjCIvarDecl *ivd,
                                          const SubRegion* superRegion);

  const CXXTempObjectRegion *getCXXTempObjectRegion(Expr const *Ex,
                                                    LocationContext const *LC);

  /// Create a CXXBaseObjectRegion with the given base class for region
  /// \p Super.
  ///
  /// The type of \p Super is assumed be a class deriving from \p BaseClass.
  const CXXBaseObjectRegion *
  getCXXBaseObjectRegion(const CXXRecordDecl *BaseClass, const SubRegion *Super,
                         bool IsVirtual);

  /// Create a CXXBaseObjectRegion with the same CXXRecordDecl but a different
  /// super region.
  const CXXBaseObjectRegion *
  getCXXBaseObjectRegionWithSuper(const CXXBaseObjectRegion *baseReg,
                                  const SubRegion *superRegion) {
    return getCXXBaseObjectRegion(baseReg->getDecl(), superRegion,
                                  baseReg->isVirtual());
  }

  /// Create a CXXDerivedObjectRegion with the given derived class for region
  /// \p Super. This should not be used for casting an existing
  /// CXXBaseObjectRegion back to the derived type; instead, CXXBaseObjectRegion
  /// should be removed.
  const CXXDerivedObjectRegion *
  getCXXDerivedObjectRegion(const CXXRecordDecl *BaseClass,
                            const SubRegion *Super);

  const FunctionCodeRegion *getFunctionCodeRegion(const NamedDecl *FD);
  const BlockCodeRegion *getBlockCodeRegion(const BlockDecl *BD,
                                            CanQualType locTy,
                                            AnalysisDeclContext *AC);

  /// getBlockDataRegion - Get the memory region associated with an instance
  ///  of a block.  Unlike many other MemRegions, the LocationContext*
  ///  argument is allowed to be NULL for cases where we have no known
  ///  context.
  const BlockDataRegion *getBlockDataRegion(const BlockCodeRegion *bc,
                                            const LocationContext *lc,
                                            unsigned blockCount);

  /// Create a CXXTempObjectRegion for temporaries which are lifetime-extended
  /// by static references. This differs from getCXXTempObjectRegion in the
  /// super-region used.
  const CXXTempObjectRegion *getCXXStaticTempObjectRegion(const Expr *Ex);

private:
  template <typename RegionTy, typename SuperTy,
            typename Arg1Ty>
  RegionTy* getSubRegion(const Arg1Ty arg1,
                         const SuperTy* superRegion);

  template <typename RegionTy, typename SuperTy,
            typename Arg1Ty, typename Arg2Ty>
  RegionTy* getSubRegion(const Arg1Ty arg1, const Arg2Ty arg2,
                         const SuperTy* superRegion);

  template <typename RegionTy, typename SuperTy,
            typename Arg1Ty, typename Arg2Ty, typename Arg3Ty>
  RegionTy* getSubRegion(const Arg1Ty arg1, const Arg2Ty arg2,
                         const Arg3Ty arg3,
                         const SuperTy* superRegion);

  template <typename REG>
  const REG* LazyAllocate(REG*& region);

  template <typename REG, typename ARG>
  const REG* LazyAllocate(REG*& region, ARG a);
};

//===----------------------------------------------------------------------===//
// Out-of-line member definitions.
//===----------------------------------------------------------------------===//

inline ASTContext &MemRegion::getContext() const {
  return getMemRegionManager()->getContext();
}

//===----------------------------------------------------------------------===//
// Means for storing region/symbol handling traits.
//===----------------------------------------------------------------------===//

/// Information about invalidation for a particular region/symbol.
class RegionAndSymbolInvalidationTraits {
  using StorageTypeForKinds = unsigned char;

  llvm::DenseMap<const MemRegion *, StorageTypeForKinds> MRTraitsMap;
  llvm::DenseMap<SymbolRef, StorageTypeForKinds> SymTraitsMap;

  using const_region_iterator =
      llvm::DenseMap<const MemRegion *, StorageTypeForKinds>::const_iterator;
  using const_symbol_iterator =
      llvm::DenseMap<SymbolRef, StorageTypeForKinds>::const_iterator;

public:
  /// Describes different invalidation traits.
  enum InvalidationKinds {
    /// Tells that a region's contents is not changed.
    TK_PreserveContents = 0x1,

    /// Suppress pointer-escaping of a region.
    TK_SuppressEscape = 0x2,

    // Do not invalidate super region.
    TK_DoNotInvalidateSuperRegion = 0x4,

    /// When applied to a MemSpaceRegion, indicates the entire memory space
    /// should be invalidated.
    TK_EntireMemSpace = 0x8

    // Do not forget to extend StorageTypeForKinds if number of traits exceed
    // the number of bits StorageTypeForKinds can store.
  };

  void setTrait(SymbolRef Sym, InvalidationKinds IK);
  void setTrait(const MemRegion *MR, InvalidationKinds IK);
  bool hasTrait(SymbolRef Sym, InvalidationKinds IK) const;
  bool hasTrait(const MemRegion *MR, InvalidationKinds IK) const;
};

//===----------------------------------------------------------------------===//
// Pretty-printing regions.
//===----------------------------------------------------------------------===//
inline raw_ostream &operator<<(raw_ostream &os, const MemRegion *R) {
  R->dumpToStream(os);
  return os;
}

} // namespace ento

} // namespace clang

#endif // LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_MEMREGION_H