MemRegion.cpp revision 3eb52bb5d791630f926ff2226dae25012315ad9a 
1//== MemRegion.cpp - Abstract memory regions for static analysis --*- C++ -*--//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file defines MemRegion and its subclasses.  MemRegion defines a
11//  partially-typed abstraction of memory useful for path-sensitive dataflow
12//  analyses.
13//
14//===----------------------------------------------------------------------===//
15
16#include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h"
17#include "clang/AST/Attr.h"
18#include "clang/AST/CharUnits.h"
19#include "clang/AST/DeclObjC.h"
20#include "clang/AST/RecordLayout.h"
21#include "clang/Analysis/AnalysisContext.h"
22#include "clang/Analysis/Support/BumpVector.h"
23#include "clang/Basic/SourceManager.h"
24#include "clang/StaticAnalyzer/Core/PathSensitive/SValBuilder.h"
25#include "llvm/Support/raw_ostream.h"
26
27using namespace clang;
28using namespace ento;
29
30//===----------------------------------------------------------------------===//
31// MemRegion Construction.
32//===----------------------------------------------------------------------===//
33
34template<typename RegionTy> struct MemRegionManagerTrait;
35
36template <typename RegionTy, typename A1>
37RegionTy* MemRegionManager::getRegion(const A1 a1) {
38
39  const typename MemRegionManagerTrait<RegionTy>::SuperRegionTy *superRegion =
40  MemRegionManagerTrait<RegionTy>::getSuperRegion(*this, a1);
41
42  llvm::FoldingSetNodeID ID;
43  RegionTy::ProfileRegion(ID, a1, superRegion);
44  void *InsertPos;
45  RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID,
46                                                                   InsertPos));
47
48  if (!R) {
49    R = (RegionTy*) A.Allocate<RegionTy>();
50    new (R) RegionTy(a1, superRegion);
51    Regions.InsertNode(R, InsertPos);
52  }
53
54  return R;
55}
56
57template <typename RegionTy, typename A1>
58RegionTy* MemRegionManager::getSubRegion(const A1 a1,
59                                         const MemRegion *superRegion) {
60  llvm::FoldingSetNodeID ID;
61  RegionTy::ProfileRegion(ID, a1, superRegion);
62  void *InsertPos;
63  RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID,
64                                                                   InsertPos));
65
66  if (!R) {
67    R = (RegionTy*) A.Allocate<RegionTy>();
68    new (R) RegionTy(a1, superRegion);
69    Regions.InsertNode(R, InsertPos);
70  }
71
72  return R;
73}
74
75template <typename RegionTy, typename A1, typename A2>
76RegionTy* MemRegionManager::getRegion(const A1 a1, const A2 a2) {
77
78  const typename MemRegionManagerTrait<RegionTy>::SuperRegionTy *superRegion =
79  MemRegionManagerTrait<RegionTy>::getSuperRegion(*this, a1, a2);
80
81  llvm::FoldingSetNodeID ID;
82  RegionTy::ProfileRegion(ID, a1, a2, superRegion);
83  void *InsertPos;
84  RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID,
85                                                                   InsertPos));
86
87  if (!R) {
88    R = (RegionTy*) A.Allocate<RegionTy>();
89    new (R) RegionTy(a1, a2, superRegion);
90    Regions.InsertNode(R, InsertPos);
91  }
92
93  return R;
94}
95
96template <typename RegionTy, typename A1, typename A2>
97RegionTy* MemRegionManager::getSubRegion(const A1 a1, const A2 a2,
98                                         const MemRegion *superRegion) {
99
100  llvm::FoldingSetNodeID ID;
101  RegionTy::ProfileRegion(ID, a1, a2, superRegion);
102  void *InsertPos;
103  RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID,
104                                                                   InsertPos));
105
106  if (!R) {
107    R = (RegionTy*) A.Allocate<RegionTy>();
108    new (R) RegionTy(a1, a2, superRegion);
109    Regions.InsertNode(R, InsertPos);
110  }
111
112  return R;
113}
114
115template <typename RegionTy, typename A1, typename A2, typename A3>
116RegionTy* MemRegionManager::getSubRegion(const A1 a1, const A2 a2, const A3 a3,
117                                         const MemRegion *superRegion) {
118
119  llvm::FoldingSetNodeID ID;
120  RegionTy::ProfileRegion(ID, a1, a2, a3, superRegion);
121  void *InsertPos;
122  RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID,
123                                                                   InsertPos));
124
125  if (!R) {
126    R = (RegionTy*) A.Allocate<RegionTy>();
127    new (R) RegionTy(a1, a2, a3, superRegion);
128    Regions.InsertNode(R, InsertPos);
129  }
130
131  return R;
132}
133
134//===----------------------------------------------------------------------===//
135// Object destruction.
136//===----------------------------------------------------------------------===//
137
138MemRegion::~MemRegion() {}
139
140MemRegionManager::~MemRegionManager() {
141  // All regions and their data are BumpPtrAllocated.  No need to call
142  // their destructors.
143}
144
145//===----------------------------------------------------------------------===//
146// Basic methods.
147//===----------------------------------------------------------------------===//
148
149bool SubRegion::isSubRegionOf(const MemRegion* R) const {
150  const MemRegion* r = getSuperRegion();
151  while (r != 0) {
152    if (r == R)
153      return true;
154    if (const SubRegion* sr = dyn_cast<SubRegion>(r))
155      r = sr->getSuperRegion();
156    else
157      break;
158  }
159  return false;
160}
161
162MemRegionManager* SubRegion::getMemRegionManager() const {
163  const SubRegion* r = this;
164  do {
165    const MemRegion *superRegion = r->getSuperRegion();
166    if (const SubRegion *sr = dyn_cast<SubRegion>(superRegion)) {
167      r = sr;
168      continue;
169    }
170    return superRegion->getMemRegionManager();
171  } while (1);
172}
173
174const StackFrameContext *VarRegion::getStackFrame() const {
175  const StackSpaceRegion *SSR = dyn_cast<StackSpaceRegion>(getMemorySpace());
176  return SSR ? SSR->getStackFrame() : NULL;
177}
178
179//===----------------------------------------------------------------------===//
180// Region extents.
181//===----------------------------------------------------------------------===//
182
183DefinedOrUnknownSVal TypedValueRegion::getExtent(SValBuilder &svalBuilder) const {
184  ASTContext &Ctx = svalBuilder.getContext();
185  QualType T = getDesugaredValueType(Ctx);
186
187  if (isa<VariableArrayType>(T))
188    return nonloc::SymbolVal(svalBuilder.getSymbolManager().getExtentSymbol(this));
189  if (T->isIncompleteType())
190    return UnknownVal();
191
192  CharUnits size = Ctx.getTypeSizeInChars(T);
193  QualType sizeTy = svalBuilder.getArrayIndexType();
194  return svalBuilder.makeIntVal(size.getQuantity(), sizeTy);
195}
196
197DefinedOrUnknownSVal FieldRegion::getExtent(SValBuilder &svalBuilder) const {
198  // Force callers to deal with bitfields explicitly.
199  if (getDecl()->isBitField())
200    return UnknownVal();
201
202  DefinedOrUnknownSVal Extent = DeclRegion::getExtent(svalBuilder);
203
204  // A zero-length array at the end of a struct often stands for dynamically-
205  // allocated extra memory.
206  if (Extent.isZeroConstant()) {
207    QualType T = getDesugaredValueType(svalBuilder.getContext());
208
209    if (isa<ConstantArrayType>(T))
210      return UnknownVal();
211  }
212
213  return Extent;
214}
215
216DefinedOrUnknownSVal AllocaRegion::getExtent(SValBuilder &svalBuilder) const {
217  return nonloc::SymbolVal(svalBuilder.getSymbolManager().getExtentSymbol(this));
218}
219
220DefinedOrUnknownSVal SymbolicRegion::getExtent(SValBuilder &svalBuilder) const {
221  return nonloc::SymbolVal(svalBuilder.getSymbolManager().getExtentSymbol(this));
222}
223
224DefinedOrUnknownSVal StringRegion::getExtent(SValBuilder &svalBuilder) const {
225  return svalBuilder.makeIntVal(getStringLiteral()->getByteLength()+1,
226                                svalBuilder.getArrayIndexType());
227}
228
229ObjCIvarRegion::ObjCIvarRegion(const ObjCIvarDecl *ivd, const MemRegion* sReg)
230  : DeclRegion(ivd, sReg, ObjCIvarRegionKind) {}
231
232const ObjCIvarDecl *ObjCIvarRegion::getDecl() const {
233  return cast<ObjCIvarDecl>(D);
234}
235
236QualType ObjCIvarRegion::getValueType() const {
237  return getDecl()->getType();
238}
239
240QualType CXXBaseObjectRegion::getValueType() const {
241  return QualType(getDecl()->getTypeForDecl(), 0);
242}
243
244//===----------------------------------------------------------------------===//
245// FoldingSet profiling.
246//===----------------------------------------------------------------------===//
247
248void MemSpaceRegion::Profile(llvm::FoldingSetNodeID& ID) const {
249  ID.AddInteger((unsigned)getKind());
250}
251
252void StackSpaceRegion::Profile(llvm::FoldingSetNodeID &ID) const {
253  ID.AddInteger((unsigned)getKind());
254  ID.AddPointer(getStackFrame());
255}
256
257void StaticGlobalSpaceRegion::Profile(llvm::FoldingSetNodeID &ID) const {
258  ID.AddInteger((unsigned)getKind());
259  ID.AddPointer(getCodeRegion());
260}
261
262void StringRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
263                                 const StringLiteral* Str,
264                                 const MemRegion* superRegion) {
265  ID.AddInteger((unsigned) StringRegionKind);
266  ID.AddPointer(Str);
267  ID.AddPointer(superRegion);
268}
269
270void ObjCStringRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
271                                     const ObjCStringLiteral* Str,
272                                     const MemRegion* superRegion) {
273  ID.AddInteger((unsigned) ObjCStringRegionKind);
274  ID.AddPointer(Str);
275  ID.AddPointer(superRegion);
276}
277
278void AllocaRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
279                                 const Expr *Ex, unsigned cnt,
280                                 const MemRegion *superRegion) {
281  ID.AddInteger((unsigned) AllocaRegionKind);
282  ID.AddPointer(Ex);
283  ID.AddInteger(cnt);
284  ID.AddPointer(superRegion);
285}
286
287void AllocaRegion::Profile(llvm::FoldingSetNodeID& ID) const {
288  ProfileRegion(ID, Ex, Cnt, superRegion);
289}
290
291void CompoundLiteralRegion::Profile(llvm::FoldingSetNodeID& ID) const {
292  CompoundLiteralRegion::ProfileRegion(ID, CL, superRegion);
293}
294
295void CompoundLiteralRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
296                                          const CompoundLiteralExpr *CL,
297                                          const MemRegion* superRegion) {
298  ID.AddInteger((unsigned) CompoundLiteralRegionKind);
299  ID.AddPointer(CL);
300  ID.AddPointer(superRegion);
301}
302
303void CXXThisRegion::ProfileRegion(llvm::FoldingSetNodeID &ID,
304                                  const PointerType *PT,
305                                  const MemRegion *sRegion) {
306  ID.AddInteger((unsigned) CXXThisRegionKind);
307  ID.AddPointer(PT);
308  ID.AddPointer(sRegion);
309}
310
311void CXXThisRegion::Profile(llvm::FoldingSetNodeID &ID) const {
312  CXXThisRegion::ProfileRegion(ID, ThisPointerTy, superRegion);
313}
314
315void ObjCIvarRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
316                                   const ObjCIvarDecl *ivd,
317                                   const MemRegion* superRegion) {
318  DeclRegion::ProfileRegion(ID, ivd, superRegion, ObjCIvarRegionKind);
319}
320
321void DeclRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, const Decl *D,
322                               const MemRegion* superRegion, Kind k) {
323  ID.AddInteger((unsigned) k);
324  ID.AddPointer(D);
325  ID.AddPointer(superRegion);
326}
327
328void DeclRegion::Profile(llvm::FoldingSetNodeID& ID) const {
329  DeclRegion::ProfileRegion(ID, D, superRegion, getKind());
330}
331
332void VarRegion::Profile(llvm::FoldingSetNodeID &ID) const {
333  VarRegion::ProfileRegion(ID, getDecl(), superRegion);
334}
335
336void SymbolicRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, SymbolRef sym,
337                                   const MemRegion *sreg) {
338  ID.AddInteger((unsigned) MemRegion::SymbolicRegionKind);
339  ID.Add(sym);
340  ID.AddPointer(sreg);
341}
342
343void SymbolicRegion::Profile(llvm::FoldingSetNodeID& ID) const {
344  SymbolicRegion::ProfileRegion(ID, sym, getSuperRegion());
345}
346
347void ElementRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
348                                  QualType ElementType, SVal Idx,
349                                  const MemRegion* superRegion) {
350  ID.AddInteger(MemRegion::ElementRegionKind);
351  ID.Add(ElementType);
352  ID.AddPointer(superRegion);
353  Idx.Profile(ID);
354}
355
356void ElementRegion::Profile(llvm::FoldingSetNodeID& ID) const {
357  ElementRegion::ProfileRegion(ID, ElementType, Index, superRegion);
358}
359
360void FunctionTextRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
361                                       const NamedDecl *FD,
362                                       const MemRegion*) {
363  ID.AddInteger(MemRegion::FunctionTextRegionKind);
364  ID.AddPointer(FD);
365}
366
367void FunctionTextRegion::Profile(llvm::FoldingSetNodeID& ID) const {
368  FunctionTextRegion::ProfileRegion(ID, FD, superRegion);
369}
370
371void BlockTextRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
372                                    const BlockDecl *BD, CanQualType,
373                                    const AnalysisDeclContext *AC,
374                                    const MemRegion*) {
375  ID.AddInteger(MemRegion::BlockTextRegionKind);
376  ID.AddPointer(BD);
377}
378
379void BlockTextRegion::Profile(llvm::FoldingSetNodeID& ID) const {
380  BlockTextRegion::ProfileRegion(ID, BD, locTy, AC, superRegion);
381}
382
383void BlockDataRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
384                                    const BlockTextRegion *BC,
385                                    const LocationContext *LC,
386                                    unsigned BlkCount,
387                                    const MemRegion *sReg) {
388  ID.AddInteger(MemRegion::BlockDataRegionKind);
389  ID.AddPointer(BC);
390  ID.AddPointer(LC);
391  ID.AddInteger(BlkCount);
392  ID.AddPointer(sReg);
393}
394
395void BlockDataRegion::Profile(llvm::FoldingSetNodeID& ID) const {
396  BlockDataRegion::ProfileRegion(ID, BC, LC, BlockCount, getSuperRegion());
397}
398
399void CXXTempObjectRegion::ProfileRegion(llvm::FoldingSetNodeID &ID,
400                                        Expr const *Ex,
401                                        const MemRegion *sReg) {
402  ID.AddPointer(Ex);
403  ID.AddPointer(sReg);
404}
405
406void CXXTempObjectRegion::Profile(llvm::FoldingSetNodeID &ID) const {
407  ProfileRegion(ID, Ex, getSuperRegion());
408}
409
410void CXXBaseObjectRegion::ProfileRegion(llvm::FoldingSetNodeID &ID,
411                                        const CXXRecordDecl *RD,
412                                        bool IsVirtual,
413                                        const MemRegion *SReg) {
414  ID.AddPointer(RD);
415  ID.AddBoolean(IsVirtual);
416  ID.AddPointer(SReg);
417}
418
419void CXXBaseObjectRegion::Profile(llvm::FoldingSetNodeID &ID) const {
420  ProfileRegion(ID, getDecl(), isVirtual(), superRegion);
421}
422
423//===----------------------------------------------------------------------===//
424// Region anchors.
425//===----------------------------------------------------------------------===//
426
427void GlobalsSpaceRegion::anchor() { }
428void HeapSpaceRegion::anchor() { }
429void UnknownSpaceRegion::anchor() { }
430void StackLocalsSpaceRegion::anchor() { }
431void StackArgumentsSpaceRegion::anchor() { }
432void TypedRegion::anchor() { }
433void TypedValueRegion::anchor() { }
434void CodeTextRegion::anchor() { }
435void SubRegion::anchor() { }
436
437//===----------------------------------------------------------------------===//
438// Region pretty-printing.
439//===----------------------------------------------------------------------===//
440
441void MemRegion::dump() const {
442  dumpToStream(llvm::errs());
443}
444
445std::string MemRegion::getString() const {
446  std::string s;
447  llvm::raw_string_ostream os(s);
448  dumpToStream(os);
449  return os.str();
450}
451
452void MemRegion::dumpToStream(raw_ostream &os) const {
453  os << "<Unknown Region>";
454}
455
456void AllocaRegion::dumpToStream(raw_ostream &os) const {
457  os << "alloca{" << (const void*) Ex << ',' << Cnt << '}';
458}
459
460void FunctionTextRegion::dumpToStream(raw_ostream &os) const {
461  os << "code{" << getDecl()->getDeclName().getAsString() << '}';
462}
463
464void BlockTextRegion::dumpToStream(raw_ostream &os) const {
465  os << "block_code{" << (const void*) this << '}';
466}
467
468void BlockDataRegion::dumpToStream(raw_ostream &os) const {
469  os << "block_data{" << BC;
470  os << "; ";
471  for (BlockDataRegion::referenced_vars_iterator
472         I = referenced_vars_begin(),
473         E = referenced_vars_end(); I != E; ++I)
474    os << "(" << I.getCapturedRegion() << "," <<
475                 I.getOriginalRegion() << ") ";
476  os << '}';
477}
478
479void CompoundLiteralRegion::dumpToStream(raw_ostream &os) const {
480  // FIXME: More elaborate pretty-printing.
481  os << "{ " << (const void*) CL <<  " }";
482}
483
484void CXXTempObjectRegion::dumpToStream(raw_ostream &os) const {
485  os << "temp_object{" << getValueType().getAsString() << ','
486     << (const void*) Ex << '}';
487}
488
489void CXXBaseObjectRegion::dumpToStream(raw_ostream &os) const {
490  os << "base{" << superRegion << ',' << getDecl()->getName() << '}';
491}
492
493void CXXThisRegion::dumpToStream(raw_ostream &os) const {
494  os << "this";
495}
496
497void ElementRegion::dumpToStream(raw_ostream &os) const {
498  os << "element{" << superRegion << ','
499     << Index << ',' << getElementType().getAsString() << '}';
500}
501
502void FieldRegion::dumpToStream(raw_ostream &os) const {
503  os << superRegion << "->" << *getDecl();
504}
505
506void ObjCIvarRegion::dumpToStream(raw_ostream &os) const {
507  os << "ivar{" << superRegion << ',' << *getDecl() << '}';
508}
509
510void StringRegion::dumpToStream(raw_ostream &os) const {
511  Str->printPretty(os, 0, PrintingPolicy(getContext().getLangOpts()));
512}
513
514void ObjCStringRegion::dumpToStream(raw_ostream &os) const {
515  Str->printPretty(os, 0, PrintingPolicy(getContext().getLangOpts()));
516}
517
518void SymbolicRegion::dumpToStream(raw_ostream &os) const {
519  os << "SymRegion{" << sym << '}';
520}
521
522void VarRegion::dumpToStream(raw_ostream &os) const {
523  os << *cast<VarDecl>(D);
524}
525
526void RegionRawOffset::dump() const {
527  dumpToStream(llvm::errs());
528}
529
530void RegionRawOffset::dumpToStream(raw_ostream &os) const {
531  os << "raw_offset{" << getRegion() << ',' << getOffset().getQuantity() << '}';
532}
533
534void StaticGlobalSpaceRegion::dumpToStream(raw_ostream &os) const {
535  os << "StaticGlobalsMemSpace{" << CR << '}';
536}
537
538void GlobalInternalSpaceRegion::dumpToStream(raw_ostream &os) const {
539  os << "GlobalInternalSpaceRegion";
540}
541
542void GlobalSystemSpaceRegion::dumpToStream(raw_ostream &os) const {
543  os << "GlobalSystemSpaceRegion";
544}
545
546void GlobalImmutableSpaceRegion::dumpToStream(raw_ostream &os) const {
547  os << "GlobalImmutableSpaceRegion";
548}
549
550void HeapSpaceRegion::dumpToStream(raw_ostream &os) const {
551  os << "HeapSpaceRegion";
552}
553
554void UnknownSpaceRegion::dumpToStream(raw_ostream &os) const {
555  os << "UnknownSpaceRegion";
556}
557
558void StackArgumentsSpaceRegion::dumpToStream(raw_ostream &os) const {
559  os << "StackArgumentsSpaceRegion";
560}
561
562void StackLocalsSpaceRegion::dumpToStream(raw_ostream &os) const {
563  os << "StackLocalsSpaceRegion";
564}
565
566bool MemRegion::canPrintPretty() const {
567  return canPrintPrettyAsExpr();
568}
569
570bool MemRegion::canPrintPrettyAsExpr() const {
571  return false;
572}
573
574void MemRegion::printPretty(raw_ostream &os) const {
575  assert(canPrintPretty() && "This region cannot be printed pretty.");
576  os << "'";
577  printPrettyAsExpr(os);
578  os << "'";
579  return;
580}
581
582void MemRegion::printPrettyAsExpr(raw_ostream &os) const {
583  llvm_unreachable("This region cannot be printed pretty.");
584  return;
585}
586
587bool VarRegion::canPrintPrettyAsExpr() const {
588  return true;
589}
590
591void VarRegion::printPrettyAsExpr(raw_ostream &os) const {
592  os << getDecl()->getName();
593}
594
595bool ObjCIvarRegion::canPrintPrettyAsExpr() const {
596  return true;
597}
598
599void ObjCIvarRegion::printPrettyAsExpr(raw_ostream &os) const {
600  os << getDecl()->getName();
601}
602
603bool FieldRegion::canPrintPretty() const {
604  return true;
605}
606
607bool FieldRegion::canPrintPrettyAsExpr() const {
608  return superRegion->canPrintPrettyAsExpr();
609}
610
611void FieldRegion::printPrettyAsExpr(raw_ostream &os) const {
612  assert(canPrintPrettyAsExpr());
613  superRegion->printPrettyAsExpr(os);
614  os << "." << getDecl()->getName();
615}
616
617void FieldRegion::printPretty(raw_ostream &os) const {
618  if (canPrintPrettyAsExpr()) {
619    os << "\'";
620    printPrettyAsExpr(os);
621    os << "'";
622  } else {
623    os << "field " << "\'" << getDecl()->getName() << "'";
624  }
625  return;
626}
627
628bool CXXBaseObjectRegion::canPrintPrettyAsExpr() const {
629  return superRegion->canPrintPrettyAsExpr();
630}
631
632void CXXBaseObjectRegion::printPrettyAsExpr(raw_ostream &os) const {
633  superRegion->printPrettyAsExpr(os);
634}
635
636//===----------------------------------------------------------------------===//
637// MemRegionManager methods.
638//===----------------------------------------------------------------------===//
639
640template <typename REG>
641const REG *MemRegionManager::LazyAllocate(REG*& region) {
642  if (!region) {
643    region = (REG*) A.Allocate<REG>();
644    new (region) REG(this);
645  }
646
647  return region;
648}
649
650template <typename REG, typename ARG>
651const REG *MemRegionManager::LazyAllocate(REG*& region, ARG a) {
652  if (!region) {
653    region = (REG*) A.Allocate<REG>();
654    new (region) REG(this, a);
655  }
656
657  return region;
658}
659
660const StackLocalsSpaceRegion*
661MemRegionManager::getStackLocalsRegion(const StackFrameContext *STC) {
662  assert(STC);
663  StackLocalsSpaceRegion *&R = StackLocalsSpaceRegions[STC];
664
665  if (R)
666    return R;
667
668  R = A.Allocate<StackLocalsSpaceRegion>();
669  new (R) StackLocalsSpaceRegion(this, STC);
670  return R;
671}
672
673const StackArgumentsSpaceRegion *
674MemRegionManager::getStackArgumentsRegion(const StackFrameContext *STC) {
675  assert(STC);
676  StackArgumentsSpaceRegion *&R = StackArgumentsSpaceRegions[STC];
677
678  if (R)
679    return R;
680
681  R = A.Allocate<StackArgumentsSpaceRegion>();
682  new (R) StackArgumentsSpaceRegion(this, STC);
683  return R;
684}
685
686const GlobalsSpaceRegion
687*MemRegionManager::getGlobalsRegion(MemRegion::Kind K,
688                                    const CodeTextRegion *CR) {
689  if (!CR) {
690    if (K == MemRegion::GlobalSystemSpaceRegionKind)
691      return LazyAllocate(SystemGlobals);
692    if (K == MemRegion::GlobalImmutableSpaceRegionKind)
693      return LazyAllocate(ImmutableGlobals);
694    assert(K == MemRegion::GlobalInternalSpaceRegionKind);
695    return LazyAllocate(InternalGlobals);
696  }
697
698  assert(K == MemRegion::StaticGlobalSpaceRegionKind);
699  StaticGlobalSpaceRegion *&R = StaticsGlobalSpaceRegions[CR];
700  if (R)
701    return R;
702
703  R = A.Allocate<StaticGlobalSpaceRegion>();
704  new (R) StaticGlobalSpaceRegion(this, CR);
705  return R;
706}
707
708const HeapSpaceRegion *MemRegionManager::getHeapRegion() {
709  return LazyAllocate(heap);
710}
711
712const MemSpaceRegion *MemRegionManager::getUnknownRegion() {
713  return LazyAllocate(unknown);
714}
715
716const MemSpaceRegion *MemRegionManager::getCodeRegion() {
717  return LazyAllocate(code);
718}
719
720//===----------------------------------------------------------------------===//
721// Constructing regions.
722//===----------------------------------------------------------------------===//
723const StringRegion* MemRegionManager::getStringRegion(const StringLiteral* Str){
724  return getSubRegion<StringRegion>(Str, getGlobalsRegion());
725}
726
727const ObjCStringRegion *
728MemRegionManager::getObjCStringRegion(const ObjCStringLiteral* Str){
729  return getSubRegion<ObjCStringRegion>(Str, getGlobalsRegion());
730}
731
732/// Look through a chain of LocationContexts to either find the
733/// StackFrameContext that matches a DeclContext, or find a VarRegion
734/// for a variable captured by a block.
735static llvm::PointerUnion<const StackFrameContext *, const VarRegion *>
736getStackOrCaptureRegionForDeclContext(const LocationContext *LC,
737                                      const DeclContext *DC,
738                                      const VarDecl *VD) {
739  while (LC) {
740    if (const StackFrameContext *SFC = dyn_cast<StackFrameContext>(LC)) {
741      if (cast<DeclContext>(SFC->getDecl()) == DC)
742        return SFC;
743    }
744    if (const BlockInvocationContext *BC =
745        dyn_cast<BlockInvocationContext>(LC)) {
746      const BlockDataRegion *BR =
747        static_cast<const BlockDataRegion*>(BC->getContextData());
748      // FIXME: This can be made more efficient.
749      for (BlockDataRegion::referenced_vars_iterator
750           I = BR->referenced_vars_begin(),
751           E = BR->referenced_vars_end(); I != E; ++I) {
752        if (const VarRegion *VR = dyn_cast<VarRegion>(I.getOriginalRegion()))
753          if (VR->getDecl() == VD)
754            return cast<VarRegion>(I.getCapturedRegion());
755      }
756    }
757
758    LC = LC->getParent();
759  }
760  return (const StackFrameContext*)0;
761}
762
763const VarRegion* MemRegionManager::getVarRegion(const VarDecl *D,
764                                                const LocationContext *LC) {
765  const MemRegion *sReg = 0;
766
767  if (D->hasGlobalStorage() && !D->isStaticLocal()) {
768
769    // First handle the globals defined in system headers.
770    if (C.getSourceManager().isInSystemHeader(D->getLocation())) {
771      // Whitelist the system globals which often DO GET modified, assume the
772      // rest are immutable.
773      if (D->getName().find("errno") != StringRef::npos)
774        sReg = getGlobalsRegion(MemRegion::GlobalSystemSpaceRegionKind);
775      else
776        sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
777
778    // Treat other globals as GlobalInternal unless they are constants.
779    } else {
780      QualType GQT = D->getType();
781      const Type *GT = GQT.getTypePtrOrNull();
782      // TODO: We could walk the complex types here and see if everything is
783      // constified.
784      if (GT && GQT.isConstQualified() && GT->isArithmeticType())
785        sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
786      else
787        sReg = getGlobalsRegion();
788    }
789
790  // Finally handle static locals.
791  } else {
792    // FIXME: Once we implement scope handling, we will need to properly lookup
793    // 'D' to the proper LocationContext.
794    const DeclContext *DC = D->getDeclContext();
795    llvm::PointerUnion<const StackFrameContext *, const VarRegion *> V =
796      getStackOrCaptureRegionForDeclContext(LC, DC, D);
797
798    if (V.is<const VarRegion*>())
799      return V.get<const VarRegion*>();
800
801    const StackFrameContext *STC = V.get<const StackFrameContext*>();
802
803    if (!STC)
804      sReg = getUnknownRegion();
805    else {
806      if (D->hasLocalStorage()) {
807        sReg = isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)
808               ? static_cast<const MemRegion*>(getStackArgumentsRegion(STC))
809               : static_cast<const MemRegion*>(getStackLocalsRegion(STC));
810      }
811      else {
812        assert(D->isStaticLocal());
813        const Decl *STCD = STC->getDecl();
814        if (isa<FunctionDecl>(STCD) || isa<ObjCMethodDecl>(STCD))
815          sReg = getGlobalsRegion(MemRegion::StaticGlobalSpaceRegionKind,
816                                  getFunctionTextRegion(cast<NamedDecl>(STCD)));
817        else if (const BlockDecl *BD = dyn_cast<BlockDecl>(STCD)) {
818          // FIXME: The fallback type here is totally bogus -- though it should
819          // never be queried, it will prevent uniquing with the real
820          // BlockTextRegion. Ideally we'd fix the AST so that we always had a
821          // signature.
822          QualType T;
823          if (const TypeSourceInfo *TSI = BD->getSignatureAsWritten())
824            T = TSI->getType();
825          else
826            T = getContext().getFunctionNoProtoType(getContext().VoidTy);
827
828          const BlockTextRegion *BTR =
829            getBlockTextRegion(BD, C.getCanonicalType(T),
830                               STC->getAnalysisDeclContext());
831          sReg = getGlobalsRegion(MemRegion::StaticGlobalSpaceRegionKind,
832                                  BTR);
833        }
834        else {
835          sReg = getGlobalsRegion();
836        }
837      }
838    }
839  }
840
841  return getSubRegion<VarRegion>(D, sReg);
842}
843
844const VarRegion *MemRegionManager::getVarRegion(const VarDecl *D,
845                                                const MemRegion *superR) {
846  return getSubRegion<VarRegion>(D, superR);
847}
848
849const BlockDataRegion *
850MemRegionManager::getBlockDataRegion(const BlockTextRegion *BC,
851                                     const LocationContext *LC,
852                                     unsigned blockCount) {
853  const MemRegion *sReg = 0;
854  const BlockDecl *BD = BC->getDecl();
855  if (!BD->hasCaptures()) {
856    // This handles 'static' blocks.
857    sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
858  }
859  else {
860    if (LC) {
861      // FIXME: Once we implement scope handling, we want the parent region
862      // to be the scope.
863      const StackFrameContext *STC = LC->getCurrentStackFrame();
864      assert(STC);
865      sReg = getStackLocalsRegion(STC);
866    }
867    else {
868      // We allow 'LC' to be NULL for cases where want BlockDataRegions
869      // without context-sensitivity.
870      sReg = getUnknownRegion();
871    }
872  }
873
874  return getSubRegion<BlockDataRegion>(BC, LC, blockCount, sReg);
875}
876
877const CXXTempObjectRegion *
878MemRegionManager::getCXXStaticTempObjectRegion(const Expr *Ex) {
879  return getSubRegion<CXXTempObjectRegion>(
880      Ex, getGlobalsRegion(MemRegion::GlobalInternalSpaceRegionKind, NULL));
881}
882
883const CompoundLiteralRegion*
884MemRegionManager::getCompoundLiteralRegion(const CompoundLiteralExpr *CL,
885                                           const LocationContext *LC) {
886
887  const MemRegion *sReg = 0;
888
889  if (CL->isFileScope())
890    sReg = getGlobalsRegion();
891  else {
892    const StackFrameContext *STC = LC->getCurrentStackFrame();
893    assert(STC);
894    sReg = getStackLocalsRegion(STC);
895  }
896
897  return getSubRegion<CompoundLiteralRegion>(CL, sReg);
898}
899
900const ElementRegion*
901MemRegionManager::getElementRegion(QualType elementType, NonLoc Idx,
902                                   const MemRegion* superRegion,
903                                   ASTContext &Ctx){
904
905  QualType T = Ctx.getCanonicalType(elementType).getUnqualifiedType();
906
907  llvm::FoldingSetNodeID ID;
908  ElementRegion::ProfileRegion(ID, T, Idx, superRegion);
909
910  void *InsertPos;
911  MemRegion* data = Regions.FindNodeOrInsertPos(ID, InsertPos);
912  ElementRegion* R = cast_or_null<ElementRegion>(data);
913
914  if (!R) {
915    R = (ElementRegion*) A.Allocate<ElementRegion>();
916    new (R) ElementRegion(T, Idx, superRegion);
917    Regions.InsertNode(R, InsertPos);
918  }
919
920  return R;
921}
922
923const FunctionTextRegion *
924MemRegionManager::getFunctionTextRegion(const NamedDecl *FD) {
925  return getSubRegion<FunctionTextRegion>(FD, getCodeRegion());
926}
927
928const BlockTextRegion *
929MemRegionManager::getBlockTextRegion(const BlockDecl *BD, CanQualType locTy,
930                                     AnalysisDeclContext *AC) {
931  return getSubRegion<BlockTextRegion>(BD, locTy, AC, getCodeRegion());
932}
933
934
935/// getSymbolicRegion - Retrieve or create a "symbolic" memory region.
936const SymbolicRegion *MemRegionManager::getSymbolicRegion(SymbolRef sym) {
937  return getSubRegion<SymbolicRegion>(sym, getUnknownRegion());
938}
939
940const SymbolicRegion *MemRegionManager::getSymbolicHeapRegion(SymbolRef Sym) {
941  return getSubRegion<SymbolicRegion>(Sym, getHeapRegion());
942}
943
944const FieldRegion*
945MemRegionManager::getFieldRegion(const FieldDecl *d,
946                                 const MemRegion* superRegion){
947  return getSubRegion<FieldRegion>(d, superRegion);
948}
949
950const ObjCIvarRegion*
951MemRegionManager::getObjCIvarRegion(const ObjCIvarDecl *d,
952                                    const MemRegion* superRegion) {
953  return getSubRegion<ObjCIvarRegion>(d, superRegion);
954}
955
956const CXXTempObjectRegion*
957MemRegionManager::getCXXTempObjectRegion(Expr const *E,
958                                         LocationContext const *LC) {
959  const StackFrameContext *SFC = LC->getCurrentStackFrame();
960  assert(SFC);
961  return getSubRegion<CXXTempObjectRegion>(E, getStackLocalsRegion(SFC));
962}
963
964/// Checks whether \p BaseClass is a valid virtual or direct non-virtual base
965/// class of the type of \p Super.
966static bool isValidBaseClass(const CXXRecordDecl *BaseClass,
967                             const TypedValueRegion *Super,
968                             bool IsVirtual) {
969  BaseClass = BaseClass->getCanonicalDecl();
970
971  const CXXRecordDecl *Class = Super->getValueType()->getAsCXXRecordDecl();
972  if (!Class)
973    return true;
974
975  if (IsVirtual)
976    return Class->isVirtuallyDerivedFrom(BaseClass);
977
978  for (CXXRecordDecl::base_class_const_iterator I = Class->bases_begin(),
979                                                E = Class->bases_end();
980       I != E; ++I) {
981    if (I->getType()->getAsCXXRecordDecl()->getCanonicalDecl() == BaseClass)
982      return true;
983  }
984
985  return false;
986}
987
988const CXXBaseObjectRegion *
989MemRegionManager::getCXXBaseObjectRegion(const CXXRecordDecl *RD,
990                                         const MemRegion *Super,
991                                         bool IsVirtual) {
992  if (isa<TypedValueRegion>(Super)) {
993    assert(isValidBaseClass(RD, dyn_cast<TypedValueRegion>(Super), IsVirtual));
994    (void)&isValidBaseClass;
995
996    if (IsVirtual) {
997      // Virtual base regions should not be layered, since the layout rules
998      // are different.
999      while (const CXXBaseObjectRegion *Base =
1000               dyn_cast<CXXBaseObjectRegion>(Super)) {
1001        Super = Base->getSuperRegion();
1002      }
1003      assert(Super && !isa<MemSpaceRegion>(Super));
1004    }
1005  }
1006
1007  return getSubRegion<CXXBaseObjectRegion>(RD, IsVirtual, Super);
1008}
1009
1010const CXXThisRegion*
1011MemRegionManager::getCXXThisRegion(QualType thisPointerTy,
1012                                   const LocationContext *LC) {
1013  const StackFrameContext *STC = LC->getCurrentStackFrame();
1014  assert(STC);
1015  const PointerType *PT = thisPointerTy->getAs<PointerType>();
1016  assert(PT);
1017  return getSubRegion<CXXThisRegion>(PT, getStackArgumentsRegion(STC));
1018}
1019
1020const AllocaRegion*
1021MemRegionManager::getAllocaRegion(const Expr *E, unsigned cnt,
1022                                  const LocationContext *LC) {
1023  const StackFrameContext *STC = LC->getCurrentStackFrame();
1024  assert(STC);
1025  return getSubRegion<AllocaRegion>(E, cnt, getStackLocalsRegion(STC));
1026}
1027
1028const MemSpaceRegion *MemRegion::getMemorySpace() const {
1029  const MemRegion *R = this;
1030  const SubRegion* SR = dyn_cast<SubRegion>(this);
1031
1032  while (SR) {
1033    R = SR->getSuperRegion();
1034    SR = dyn_cast<SubRegion>(R);
1035  }
1036
1037  return dyn_cast<MemSpaceRegion>(R);
1038}
1039
1040bool MemRegion::hasStackStorage() const {
1041  return isa<StackSpaceRegion>(getMemorySpace());
1042}
1043
1044bool MemRegion::hasStackNonParametersStorage() const {
1045  return isa<StackLocalsSpaceRegion>(getMemorySpace());
1046}
1047
1048bool MemRegion::hasStackParametersStorage() const {
1049  return isa<StackArgumentsSpaceRegion>(getMemorySpace());
1050}
1051
1052bool MemRegion::hasGlobalsOrParametersStorage() const {
1053  const MemSpaceRegion *MS = getMemorySpace();
1054  return isa<StackArgumentsSpaceRegion>(MS) ||
1055         isa<GlobalsSpaceRegion>(MS);
1056}
1057
1058// getBaseRegion strips away all elements and fields, and get the base region
1059// of them.
1060const MemRegion *MemRegion::getBaseRegion() const {
1061  const MemRegion *R = this;
1062  while (true) {
1063    switch (R->getKind()) {
1064      case MemRegion::ElementRegionKind:
1065      case MemRegion::FieldRegionKind:
1066      case MemRegion::ObjCIvarRegionKind:
1067      case MemRegion::CXXBaseObjectRegionKind:
1068        R = cast<SubRegion>(R)->getSuperRegion();
1069        continue;
1070      default:
1071        break;
1072    }
1073    break;
1074  }
1075  return R;
1076}
1077
1078bool MemRegion::isSubRegionOf(const MemRegion *R) const {
1079  return false;
1080}
1081
1082//===----------------------------------------------------------------------===//
1083// View handling.
1084//===----------------------------------------------------------------------===//
1085
1086const MemRegion *MemRegion::StripCasts(bool StripBaseCasts) const {
1087  const MemRegion *R = this;
1088  while (true) {
1089    switch (R->getKind()) {
1090    case ElementRegionKind: {
1091      const ElementRegion *ER = cast<ElementRegion>(R);
1092      if (!ER->getIndex().isZeroConstant())
1093        return R;
1094      R = ER->getSuperRegion();
1095      break;
1096    }
1097    case CXXBaseObjectRegionKind:
1098      if (!StripBaseCasts)
1099        return R;
1100      R = cast<CXXBaseObjectRegion>(R)->getSuperRegion();
1101      break;
1102    default:
1103      return R;
1104    }
1105  }
1106}
1107
1108const SymbolicRegion *MemRegion::getSymbolicBase() const {
1109  const SubRegion *SubR = dyn_cast<SubRegion>(this);
1110
1111  while (SubR) {
1112    if (const SymbolicRegion *SymR = dyn_cast<SymbolicRegion>(SubR))
1113      return SymR;
1114    SubR = dyn_cast<SubRegion>(SubR->getSuperRegion());
1115  }
1116  return 0;
1117}
1118
1119// FIXME: Merge with the implementation of the same method in Store.cpp
1120static bool IsCompleteType(ASTContext &Ctx, QualType Ty) {
1121  if (const RecordType *RT = Ty->getAs<RecordType>()) {
1122    const RecordDecl *D = RT->getDecl();
1123    if (!D->getDefinition())
1124      return false;
1125  }
1126
1127  return true;
1128}
1129
1130RegionRawOffset ElementRegion::getAsArrayOffset() const {
1131  CharUnits offset = CharUnits::Zero();
1132  const ElementRegion *ER = this;
1133  const MemRegion *superR = NULL;
1134  ASTContext &C = getContext();
1135
1136  // FIXME: Handle multi-dimensional arrays.
1137
1138  while (ER) {
1139    superR = ER->getSuperRegion();
1140
1141    // FIXME: generalize to symbolic offsets.
1142    SVal index = ER->getIndex();
1143    if (Optional<nonloc::ConcreteInt> CI = index.getAs<nonloc::ConcreteInt>()) {
1144      // Update the offset.
1145      int64_t i = CI->getValue().getSExtValue();
1146
1147      if (i != 0) {
1148        QualType elemType = ER->getElementType();
1149
1150        // If we are pointing to an incomplete type, go no further.
1151        if (!IsCompleteType(C, elemType)) {
1152          superR = ER;
1153          break;
1154        }
1155
1156        CharUnits size = C.getTypeSizeInChars(elemType);
1157        offset += (i * size);
1158      }
1159
1160      // Go to the next ElementRegion (if any).
1161      ER = dyn_cast<ElementRegion>(superR);
1162      continue;
1163    }
1164
1165    return NULL;
1166  }
1167
1168  assert(superR && "super region cannot be NULL");
1169  return RegionRawOffset(superR, offset);
1170}
1171
1172
1173/// Returns true if \p Base is an immediate base class of \p Child
1174static bool isImmediateBase(const CXXRecordDecl *Child,
1175                            const CXXRecordDecl *Base) {
1176  // Note that we do NOT canonicalize the base class here, because
1177  // ASTRecordLayout doesn't either. If that leads us down the wrong path,
1178  // so be it; at least we won't crash.
1179  for (CXXRecordDecl::base_class_const_iterator I = Child->bases_begin(),
1180                                                E = Child->bases_end();
1181       I != E; ++I) {
1182    if (I->getType()->getAsCXXRecordDecl() == Base)
1183      return true;
1184  }
1185
1186  return false;
1187}
1188
1189RegionOffset MemRegion::getAsOffset() const {
1190  const MemRegion *R = this;
1191  const MemRegion *SymbolicOffsetBase = 0;
1192  int64_t Offset = 0;
1193
1194  while (1) {
1195    switch (R->getKind()) {
1196    case GenericMemSpaceRegionKind:
1197    case StackLocalsSpaceRegionKind:
1198    case StackArgumentsSpaceRegionKind:
1199    case HeapSpaceRegionKind:
1200    case UnknownSpaceRegionKind:
1201    case StaticGlobalSpaceRegionKind:
1202    case GlobalInternalSpaceRegionKind:
1203    case GlobalSystemSpaceRegionKind:
1204    case GlobalImmutableSpaceRegionKind:
1205      // Stores can bind directly to a region space to set a default value.
1206      assert(Offset == 0 && !SymbolicOffsetBase);
1207      goto Finish;
1208
1209    case FunctionTextRegionKind:
1210    case BlockTextRegionKind:
1211    case BlockDataRegionKind:
1212      // These will never have bindings, but may end up having values requested
1213      // if the user does some strange casting.
1214      if (Offset != 0)
1215        SymbolicOffsetBase = R;
1216      goto Finish;
1217
1218    case SymbolicRegionKind:
1219    case AllocaRegionKind:
1220    case CompoundLiteralRegionKind:
1221    case CXXThisRegionKind:
1222    case StringRegionKind:
1223    case ObjCStringRegionKind:
1224    case VarRegionKind:
1225    case CXXTempObjectRegionKind:
1226      // Usual base regions.
1227      goto Finish;
1228
1229    case ObjCIvarRegionKind:
1230      // This is a little strange, but it's a compromise between
1231      // ObjCIvarRegions having unknown compile-time offsets (when using the
1232      // non-fragile runtime) and yet still being distinct, non-overlapping
1233      // regions. Thus we treat them as "like" base regions for the purposes
1234      // of computing offsets.
1235      goto Finish;
1236
1237    case CXXBaseObjectRegionKind: {
1238      const CXXBaseObjectRegion *BOR = cast<CXXBaseObjectRegion>(R);
1239      R = BOR->getSuperRegion();
1240
1241      QualType Ty;
1242      bool RootIsSymbolic = false;
1243      if (const TypedValueRegion *TVR = dyn_cast<TypedValueRegion>(R)) {
1244        Ty = TVR->getDesugaredValueType(getContext());
1245      } else if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) {
1246        // If our base region is symbolic, we don't know what type it really is.
1247        // Pretend the type of the symbol is the true dynamic type.
1248        // (This will at least be self-consistent for the life of the symbol.)
1249        Ty = SR->getSymbol()->getType()->getPointeeType();
1250        RootIsSymbolic = true;
1251      }
1252
1253      const CXXRecordDecl *Child = Ty->getAsCXXRecordDecl();
1254      if (!Child) {
1255        // We cannot compute the offset of the base class.
1256        SymbolicOffsetBase = R;
1257      }
1258
1259      if (RootIsSymbolic) {
1260        // Base layers on symbolic regions may not be type-correct.
1261        // Double-check the inheritance here, and revert to a symbolic offset
1262        // if it's invalid (e.g. due to a reinterpret_cast).
1263        if (BOR->isVirtual()) {
1264          if (!Child->isVirtuallyDerivedFrom(BOR->getDecl()))
1265            SymbolicOffsetBase = R;
1266        } else {
1267          if (!isImmediateBase(Child, BOR->getDecl()))
1268            SymbolicOffsetBase = R;
1269        }
1270      }
1271
1272      // Don't bother calculating precise offsets if we already have a
1273      // symbolic offset somewhere in the chain.
1274      if (SymbolicOffsetBase)
1275        continue;
1276
1277      CharUnits BaseOffset;
1278      const ASTRecordLayout &Layout = getContext().getASTRecordLayout(Child);
1279      if (BOR->isVirtual())
1280        BaseOffset = Layout.getVBaseClassOffset(BOR->getDecl());
1281      else
1282        BaseOffset = Layout.getBaseClassOffset(BOR->getDecl());
1283
1284      // The base offset is in chars, not in bits.
1285      Offset += BaseOffset.getQuantity() * getContext().getCharWidth();
1286      break;
1287    }
1288    case ElementRegionKind: {
1289      const ElementRegion *ER = cast<ElementRegion>(R);
1290      R = ER->getSuperRegion();
1291
1292      QualType EleTy = ER->getValueType();
1293      if (!IsCompleteType(getContext(), EleTy)) {
1294        // We cannot compute the offset of the base class.
1295        SymbolicOffsetBase = R;
1296        continue;
1297      }
1298
1299      SVal Index = ER->getIndex();
1300      if (Optional<nonloc::ConcreteInt> CI =
1301              Index.getAs<nonloc::ConcreteInt>()) {
1302        // Don't bother calculating precise offsets if we already have a
1303        // symbolic offset somewhere in the chain.
1304        if (SymbolicOffsetBase)
1305          continue;
1306
1307        int64_t i = CI->getValue().getSExtValue();
1308        // This type size is in bits.
1309        Offset += i * getContext().getTypeSize(EleTy);
1310      } else {
1311        // We cannot compute offset for non-concrete index.
1312        SymbolicOffsetBase = R;
1313      }
1314      break;
1315    }
1316    case FieldRegionKind: {
1317      const FieldRegion *FR = cast<FieldRegion>(R);
1318      R = FR->getSuperRegion();
1319
1320      const RecordDecl *RD = FR->getDecl()->getParent();
1321      if (RD->isUnion() || !RD->isCompleteDefinition()) {
1322        // We cannot compute offset for incomplete type.
1323        // For unions, we could treat everything as offset 0, but we'd rather
1324        // treat each field as a symbolic offset so they aren't stored on top
1325        // of each other, since we depend on things in typed regions actually
1326        // matching their types.
1327        SymbolicOffsetBase = R;
1328      }
1329
1330      // Don't bother calculating precise offsets if we already have a
1331      // symbolic offset somewhere in the chain.
1332      if (SymbolicOffsetBase)
1333        continue;
1334
1335      // Get the field number.
1336      unsigned idx = 0;
1337      for (RecordDecl::field_iterator FI = RD->field_begin(),
1338             FE = RD->field_end(); FI != FE; ++FI, ++idx)
1339        if (FR->getDecl() == *FI)
1340          break;
1341
1342      const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
1343      // This is offset in bits.
1344      Offset += Layout.getFieldOffset(idx);
1345      break;
1346    }
1347    }
1348  }
1349
1350 Finish:
1351  if (SymbolicOffsetBase)
1352    return RegionOffset(SymbolicOffsetBase, RegionOffset::Symbolic);
1353  return RegionOffset(R, Offset);
1354}
1355
1356//===----------------------------------------------------------------------===//
1357// BlockDataRegion
1358//===----------------------------------------------------------------------===//
1359
1360std::pair<const VarRegion *, const VarRegion *>
1361BlockDataRegion::getCaptureRegions(const VarDecl *VD) {
1362  MemRegionManager &MemMgr = *getMemRegionManager();
1363  const VarRegion *VR = 0;
1364  const VarRegion *OriginalVR = 0;
1365
1366  if (!VD->getAttr<BlocksAttr>() && VD->hasLocalStorage()) {
1367    VR = MemMgr.getVarRegion(VD, this);
1368    OriginalVR = MemMgr.getVarRegion(VD, LC);
1369  }
1370  else {
1371    if (LC) {
1372      VR = MemMgr.getVarRegion(VD, LC);
1373      OriginalVR = VR;
1374    }
1375    else {
1376      VR = MemMgr.getVarRegion(VD, MemMgr.getUnknownRegion());
1377      OriginalVR = MemMgr.getVarRegion(VD, LC);
1378    }
1379  }
1380  return std::make_pair(VR, OriginalVR);
1381}
1382
1383void BlockDataRegion::LazyInitializeReferencedVars() {
1384  if (ReferencedVars)
1385    return;
1386
1387  AnalysisDeclContext *AC = getCodeRegion()->getAnalysisDeclContext();
1388  AnalysisDeclContext::referenced_decls_iterator I, E;
1389  llvm::tie(I, E) = AC->getReferencedBlockVars(BC->getDecl());
1390
1391  if (I == E) {
1392    ReferencedVars = (void*) 0x1;
1393    return;
1394  }
1395
1396  MemRegionManager &MemMgr = *getMemRegionManager();
1397  llvm::BumpPtrAllocator &A = MemMgr.getAllocator();
1398  BumpVectorContext BC(A);
1399
1400  typedef BumpVector<const MemRegion*> VarVec;
1401  VarVec *BV = (VarVec*) A.Allocate<VarVec>();
1402  new (BV) VarVec(BC, E - I);
1403  VarVec *BVOriginal = (VarVec*) A.Allocate<VarVec>();
1404  new (BVOriginal) VarVec(BC, E - I);
1405
1406  for ( ; I != E; ++I) {
1407    const VarRegion *VR = 0;
1408    const VarRegion *OriginalVR = 0;
1409    llvm::tie(VR, OriginalVR) = getCaptureRegions(*I);
1410    assert(VR);
1411    assert(OriginalVR);
1412    BV->push_back(VR, BC);
1413    BVOriginal->push_back(OriginalVR, BC);
1414  }
1415
1416  ReferencedVars = BV;
1417  OriginalVars = BVOriginal;
1418}
1419
1420BlockDataRegion::referenced_vars_iterator
1421BlockDataRegion::referenced_vars_begin() const {
1422  const_cast<BlockDataRegion*>(this)->LazyInitializeReferencedVars();
1423
1424  BumpVector<const MemRegion*> *Vec =
1425    static_cast<BumpVector<const MemRegion*>*>(ReferencedVars);
1426
1427  if (Vec == (void*) 0x1)
1428    return BlockDataRegion::referenced_vars_iterator(0, 0);
1429
1430  BumpVector<const MemRegion*> *VecOriginal =
1431    static_cast<BumpVector<const MemRegion*>*>(OriginalVars);
1432
1433  return BlockDataRegion::referenced_vars_iterator(Vec->begin(),
1434                                                   VecOriginal->begin());
1435}
1436
1437BlockDataRegion::referenced_vars_iterator
1438BlockDataRegion::referenced_vars_end() const {
1439  const_cast<BlockDataRegion*>(this)->LazyInitializeReferencedVars();
1440
1441  BumpVector<const MemRegion*> *Vec =
1442    static_cast<BumpVector<const MemRegion*>*>(ReferencedVars);
1443
1444  if (Vec == (void*) 0x1)
1445    return BlockDataRegion::referenced_vars_iterator(0, 0);
1446
1447  BumpVector<const MemRegion*> *VecOriginal =
1448    static_cast<BumpVector<const MemRegion*>*>(OriginalVars);
1449
1450  return BlockDataRegion::referenced_vars_iterator(Vec->end(),
1451                                                   VecOriginal->end());
1452}
1453
1454const VarRegion *BlockDataRegion::getOriginalRegion(const VarRegion *R) const {
1455  for (referenced_vars_iterator I = referenced_vars_begin(),
1456                                E = referenced_vars_end();
1457       I != E; ++I) {
1458    if (I.getCapturedRegion() == R)
1459      return I.getOriginalRegion();
1460  }
1461  return 0;
1462}
1463
1464//===----------------------------------------------------------------------===//
1465// RegionAndSymbolInvalidationTraits
1466//===----------------------------------------------------------------------===//
1467
1468void RegionAndSymbolInvalidationTraits::setTrait(SymbolRef Sym,
1469                                                 InvalidationKinds IK) {
1470  SymTraitsMap[Sym] |= IK;
1471}
1472
1473void RegionAndSymbolInvalidationTraits::setTrait(const MemRegion *MR,
1474                                                 InvalidationKinds IK) {
1475  assert(MR);
1476  if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(MR))
1477    setTrait(SR->getSymbol(), IK);
1478  else
1479    MRTraitsMap[MR] |= IK;
1480}
1481
1482bool RegionAndSymbolInvalidationTraits::hasTrait(SymbolRef Sym,
1483                                                 InvalidationKinds IK) {
1484  const_symbol_iterator I = SymTraitsMap.find(Sym);
1485  if (I != SymTraitsMap.end())
1486    return I->second & IK;
1487
1488  return false;
1489}
1490
1491bool RegionAndSymbolInvalidationTraits::hasTrait(const MemRegion *MR,
1492                                                 InvalidationKinds IK) {
1493  if (!MR)
1494    return false;
1495
1496  if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(MR))
1497    return hasTrait(SR->getSymbol(), IK);
1498
1499  const_region_iterator I = MRTraitsMap.find(MR);
1500  if (I != MRTraitsMap.end())
1501    return I->second & IK;
1502
1503  return false;
1504}
1505