MemRegion.cpp revision d764e20189dbb42b38ada383a0a159f6adc0d56c 
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 (isa<IncompleteArrayType>(T))
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                                    const MemRegion *sReg) {
387  ID.AddInteger(MemRegion::BlockDataRegionKind);
388  ID.AddPointer(BC);
389  ID.AddPointer(LC);
390  ID.AddPointer(sReg);
391}
392
393void BlockDataRegion::Profile(llvm::FoldingSetNodeID& ID) const {
394  BlockDataRegion::ProfileRegion(ID, BC, LC, getSuperRegion());
395}
396
397void CXXTempObjectRegion::ProfileRegion(llvm::FoldingSetNodeID &ID,
398                                        Expr const *Ex,
399                                        const MemRegion *sReg) {
400  ID.AddPointer(Ex);
401  ID.AddPointer(sReg);
402}
403
404void CXXTempObjectRegion::Profile(llvm::FoldingSetNodeID &ID) const {
405  ProfileRegion(ID, Ex, getSuperRegion());
406}
407
408void CXXBaseObjectRegion::ProfileRegion(llvm::FoldingSetNodeID &ID,
409                                        const CXXRecordDecl *RD,
410                                        bool IsVirtual,
411                                        const MemRegion *SReg) {
412  ID.AddPointer(RD);
413  ID.AddBoolean(IsVirtual);
414  ID.AddPointer(SReg);
415}
416
417void CXXBaseObjectRegion::Profile(llvm::FoldingSetNodeID &ID) const {
418  ProfileRegion(ID, getDecl(), isVirtual(), superRegion);
419}
420
421//===----------------------------------------------------------------------===//
422// Region anchors.
423//===----------------------------------------------------------------------===//
424
425void GlobalsSpaceRegion::anchor() { }
426void HeapSpaceRegion::anchor() { }
427void UnknownSpaceRegion::anchor() { }
428void StackLocalsSpaceRegion::anchor() { }
429void StackArgumentsSpaceRegion::anchor() { }
430void TypedRegion::anchor() { }
431void TypedValueRegion::anchor() { }
432void CodeTextRegion::anchor() { }
433void SubRegion::anchor() { }
434
435//===----------------------------------------------------------------------===//
436// Region pretty-printing.
437//===----------------------------------------------------------------------===//
438
439void MemRegion::dump() const {
440  dumpToStream(llvm::errs());
441}
442
443std::string MemRegion::getString() const {
444  std::string s;
445  llvm::raw_string_ostream os(s);
446  dumpToStream(os);
447  return os.str();
448}
449
450void MemRegion::dumpToStream(raw_ostream &os) const {
451  os << "<Unknown Region>";
452}
453
454void AllocaRegion::dumpToStream(raw_ostream &os) const {
455  os << "alloca{" << (const void*) Ex << ',' << Cnt << '}';
456}
457
458void FunctionTextRegion::dumpToStream(raw_ostream &os) const {
459  os << "code{" << getDecl()->getDeclName().getAsString() << '}';
460}
461
462void BlockTextRegion::dumpToStream(raw_ostream &os) const {
463  os << "block_code{" << (const void*) this << '}';
464}
465
466void BlockDataRegion::dumpToStream(raw_ostream &os) const {
467  os << "block_data{" << BC << '}';
468}
469
470void CompoundLiteralRegion::dumpToStream(raw_ostream &os) const {
471  // FIXME: More elaborate pretty-printing.
472  os << "{ " << (const void*) CL <<  " }";
473}
474
475void CXXTempObjectRegion::dumpToStream(raw_ostream &os) const {
476  os << "temp_object{" << getValueType().getAsString() << ','
477     << (const void*) Ex << '}';
478}
479
480void CXXBaseObjectRegion::dumpToStream(raw_ostream &os) const {
481  os << "base{" << superRegion << ',' << getDecl()->getName() << '}';
482}
483
484void CXXThisRegion::dumpToStream(raw_ostream &os) const {
485  os << "this";
486}
487
488void ElementRegion::dumpToStream(raw_ostream &os) const {
489  os << "element{" << superRegion << ','
490     << Index << ',' << getElementType().getAsString() << '}';
491}
492
493void FieldRegion::dumpToStream(raw_ostream &os) const {
494  os << superRegion << "->" << *getDecl();
495}
496
497void ObjCIvarRegion::dumpToStream(raw_ostream &os) const {
498  os << "ivar{" << superRegion << ',' << *getDecl() << '}';
499}
500
501void StringRegion::dumpToStream(raw_ostream &os) const {
502  Str->printPretty(os, 0, PrintingPolicy(getContext().getLangOpts()));
503}
504
505void ObjCStringRegion::dumpToStream(raw_ostream &os) const {
506  Str->printPretty(os, 0, PrintingPolicy(getContext().getLangOpts()));
507}
508
509void SymbolicRegion::dumpToStream(raw_ostream &os) const {
510  os << "SymRegion{" << sym << '}';
511}
512
513void VarRegion::dumpToStream(raw_ostream &os) const {
514  os << *cast<VarDecl>(D);
515}
516
517void RegionRawOffset::dump() const {
518  dumpToStream(llvm::errs());
519}
520
521void RegionRawOffset::dumpToStream(raw_ostream &os) const {
522  os << "raw_offset{" << getRegion() << ',' << getOffset().getQuantity() << '}';
523}
524
525void StaticGlobalSpaceRegion::dumpToStream(raw_ostream &os) const {
526  os << "StaticGlobalsMemSpace{" << CR << '}';
527}
528
529void GlobalInternalSpaceRegion::dumpToStream(raw_ostream &os) const {
530  os << "GlobalInternalSpaceRegion";
531}
532
533void GlobalSystemSpaceRegion::dumpToStream(raw_ostream &os) const {
534  os << "GlobalSystemSpaceRegion";
535}
536
537void GlobalImmutableSpaceRegion::dumpToStream(raw_ostream &os) const {
538  os << "GlobalImmutableSpaceRegion";
539}
540
541void HeapSpaceRegion::dumpToStream(raw_ostream &os) const {
542  os << "HeapSpaceRegion";
543}
544
545void UnknownSpaceRegion::dumpToStream(raw_ostream &os) const {
546  os << "UnknownSpaceRegion";
547}
548
549void StackArgumentsSpaceRegion::dumpToStream(raw_ostream &os) const {
550  os << "StackArgumentsSpaceRegion";
551}
552
553void StackLocalsSpaceRegion::dumpToStream(raw_ostream &os) const {
554  os << "StackLocalsSpaceRegion";
555}
556
557bool MemRegion::canPrintPretty() const {
558  return false;
559}
560
561void MemRegion::printPretty(raw_ostream &os) const {
562  return;
563}
564
565bool VarRegion::canPrintPretty() const {
566  return true;
567}
568
569void VarRegion::printPretty(raw_ostream &os) const {
570  os << getDecl()->getName();
571}
572
573bool ObjCIvarRegion::canPrintPretty() const {
574  return true;
575}
576
577void ObjCIvarRegion::printPretty(raw_ostream &os) const {
578  os << getDecl()->getName();
579}
580
581bool FieldRegion::canPrintPretty() const {
582  return superRegion->canPrintPretty();
583}
584
585void FieldRegion::printPretty(raw_ostream &os) const {
586  superRegion->printPretty(os);
587  os << "." << getDecl()->getName();
588}
589
590//===----------------------------------------------------------------------===//
591// MemRegionManager methods.
592//===----------------------------------------------------------------------===//
593
594template <typename REG>
595const REG *MemRegionManager::LazyAllocate(REG*& region) {
596  if (!region) {
597    region = (REG*) A.Allocate<REG>();
598    new (region) REG(this);
599  }
600
601  return region;
602}
603
604template <typename REG, typename ARG>
605const REG *MemRegionManager::LazyAllocate(REG*& region, ARG a) {
606  if (!region) {
607    region = (REG*) A.Allocate<REG>();
608    new (region) REG(this, a);
609  }
610
611  return region;
612}
613
614const StackLocalsSpaceRegion*
615MemRegionManager::getStackLocalsRegion(const StackFrameContext *STC) {
616  assert(STC);
617  StackLocalsSpaceRegion *&R = StackLocalsSpaceRegions[STC];
618
619  if (R)
620    return R;
621
622  R = A.Allocate<StackLocalsSpaceRegion>();
623  new (R) StackLocalsSpaceRegion(this, STC);
624  return R;
625}
626
627const StackArgumentsSpaceRegion *
628MemRegionManager::getStackArgumentsRegion(const StackFrameContext *STC) {
629  assert(STC);
630  StackArgumentsSpaceRegion *&R = StackArgumentsSpaceRegions[STC];
631
632  if (R)
633    return R;
634
635  R = A.Allocate<StackArgumentsSpaceRegion>();
636  new (R) StackArgumentsSpaceRegion(this, STC);
637  return R;
638}
639
640const GlobalsSpaceRegion
641*MemRegionManager::getGlobalsRegion(MemRegion::Kind K,
642                                    const CodeTextRegion *CR) {
643  if (!CR) {
644    if (K == MemRegion::GlobalSystemSpaceRegionKind)
645      return LazyAllocate(SystemGlobals);
646    if (K == MemRegion::GlobalImmutableSpaceRegionKind)
647      return LazyAllocate(ImmutableGlobals);
648    assert(K == MemRegion::GlobalInternalSpaceRegionKind);
649    return LazyAllocate(InternalGlobals);
650  }
651
652  assert(K == MemRegion::StaticGlobalSpaceRegionKind);
653  StaticGlobalSpaceRegion *&R = StaticsGlobalSpaceRegions[CR];
654  if (R)
655    return R;
656
657  R = A.Allocate<StaticGlobalSpaceRegion>();
658  new (R) StaticGlobalSpaceRegion(this, CR);
659  return R;
660}
661
662const HeapSpaceRegion *MemRegionManager::getHeapRegion() {
663  return LazyAllocate(heap);
664}
665
666const MemSpaceRegion *MemRegionManager::getUnknownRegion() {
667  return LazyAllocate(unknown);
668}
669
670const MemSpaceRegion *MemRegionManager::getCodeRegion() {
671  return LazyAllocate(code);
672}
673
674//===----------------------------------------------------------------------===//
675// Constructing regions.
676//===----------------------------------------------------------------------===//
677const StringRegion* MemRegionManager::getStringRegion(const StringLiteral* Str){
678  return getSubRegion<StringRegion>(Str, getGlobalsRegion());
679}
680
681const ObjCStringRegion *
682MemRegionManager::getObjCStringRegion(const ObjCStringLiteral* Str){
683  return getSubRegion<ObjCStringRegion>(Str, getGlobalsRegion());
684}
685
686/// Look through a chain of LocationContexts to either find the
687/// StackFrameContext that matches a DeclContext, or find a VarRegion
688/// for a variable captured by a block.
689static llvm::PointerUnion<const StackFrameContext *, const VarRegion *>
690getStackOrCaptureRegionForDeclContext(const LocationContext *LC,
691                                      const DeclContext *DC,
692                                      const VarDecl *VD) {
693  while (LC) {
694    if (const StackFrameContext *SFC = dyn_cast<StackFrameContext>(LC)) {
695      if (cast<DeclContext>(SFC->getDecl()) == DC)
696        return SFC;
697    }
698    if (const BlockInvocationContext *BC =
699        dyn_cast<BlockInvocationContext>(LC)) {
700      const BlockDataRegion *BR =
701        static_cast<const BlockDataRegion*>(BC->getContextData());
702      // FIXME: This can be made more efficient.
703      for (BlockDataRegion::referenced_vars_iterator
704           I = BR->referenced_vars_begin(),
705           E = BR->referenced_vars_end(); I != E; ++I) {
706        if (const VarRegion *VR = dyn_cast<VarRegion>(I.getOriginalRegion()))
707          if (VR->getDecl() == VD)
708            return cast<VarRegion>(I.getCapturedRegion());
709      }
710    }
711
712    LC = LC->getParent();
713  }
714  return (const StackFrameContext*)0;
715}
716
717const VarRegion* MemRegionManager::getVarRegion(const VarDecl *D,
718                                                const LocationContext *LC) {
719  const MemRegion *sReg = 0;
720
721  if (D->hasGlobalStorage() && !D->isStaticLocal()) {
722
723    // First handle the globals defined in system headers.
724    if (C.getSourceManager().isInSystemHeader(D->getLocation())) {
725      // Whitelist the system globals which often DO GET modified, assume the
726      // rest are immutable.
727      if (D->getName().find("errno") != StringRef::npos)
728        sReg = getGlobalsRegion(MemRegion::GlobalSystemSpaceRegionKind);
729      else
730        sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
731
732    // Treat other globals as GlobalInternal unless they are constants.
733    } else {
734      QualType GQT = D->getType();
735      const Type *GT = GQT.getTypePtrOrNull();
736      // TODO: We could walk the complex types here and see if everything is
737      // constified.
738      if (GT && GQT.isConstQualified() && GT->isArithmeticType())
739        sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
740      else
741        sReg = getGlobalsRegion();
742    }
743
744  // Finally handle static locals.
745  } else {
746    // FIXME: Once we implement scope handling, we will need to properly lookup
747    // 'D' to the proper LocationContext.
748    const DeclContext *DC = D->getDeclContext();
749    llvm::PointerUnion<const StackFrameContext *, const VarRegion *> V =
750      getStackOrCaptureRegionForDeclContext(LC, DC, D);
751
752    if (V.is<const VarRegion*>())
753      return V.get<const VarRegion*>();
754
755    const StackFrameContext *STC = V.get<const StackFrameContext*>();
756
757    if (!STC)
758      sReg = getUnknownRegion();
759    else {
760      if (D->hasLocalStorage()) {
761        sReg = isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)
762               ? static_cast<const MemRegion*>(getStackArgumentsRegion(STC))
763               : static_cast<const MemRegion*>(getStackLocalsRegion(STC));
764      }
765      else {
766        assert(D->isStaticLocal());
767        const Decl *STCD = STC->getDecl();
768        if (isa<FunctionDecl>(STCD) || isa<ObjCMethodDecl>(STCD))
769          sReg = getGlobalsRegion(MemRegion::StaticGlobalSpaceRegionKind,
770                                  getFunctionTextRegion(cast<NamedDecl>(STCD)));
771        else if (const BlockDecl *BD = dyn_cast<BlockDecl>(STCD)) {
772          const BlockTextRegion *BTR =
773            getBlockTextRegion(BD,
774                     C.getCanonicalType(BD->getSignatureAsWritten()->getType()),
775                     STC->getAnalysisDeclContext());
776          sReg = getGlobalsRegion(MemRegion::StaticGlobalSpaceRegionKind,
777                                  BTR);
778        }
779        else {
780          sReg = getGlobalsRegion();
781        }
782      }
783    }
784  }
785
786  return getSubRegion<VarRegion>(D, sReg);
787}
788
789const VarRegion *MemRegionManager::getVarRegion(const VarDecl *D,
790                                                const MemRegion *superR) {
791  return getSubRegion<VarRegion>(D, superR);
792}
793
794const BlockDataRegion *
795MemRegionManager::getBlockDataRegion(const BlockTextRegion *BC,
796                                     const LocationContext *LC) {
797  const MemRegion *sReg = 0;
798  const BlockDecl *BD = BC->getDecl();
799  if (!BD->hasCaptures()) {
800    // This handles 'static' blocks.
801    sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
802  }
803  else {
804    if (LC) {
805      // FIXME: Once we implement scope handling, we want the parent region
806      // to be the scope.
807      const StackFrameContext *STC = LC->getCurrentStackFrame();
808      assert(STC);
809      sReg = getStackLocalsRegion(STC);
810    }
811    else {
812      // We allow 'LC' to be NULL for cases where want BlockDataRegions
813      // without context-sensitivity.
814      sReg = getUnknownRegion();
815    }
816  }
817
818  return getSubRegion<BlockDataRegion>(BC, LC, sReg);
819}
820
821const CompoundLiteralRegion*
822MemRegionManager::getCompoundLiteralRegion(const CompoundLiteralExpr *CL,
823                                           const LocationContext *LC) {
824
825  const MemRegion *sReg = 0;
826
827  if (CL->isFileScope())
828    sReg = getGlobalsRegion();
829  else {
830    const StackFrameContext *STC = LC->getCurrentStackFrame();
831    assert(STC);
832    sReg = getStackLocalsRegion(STC);
833  }
834
835  return getSubRegion<CompoundLiteralRegion>(CL, sReg);
836}
837
838const ElementRegion*
839MemRegionManager::getElementRegion(QualType elementType, NonLoc Idx,
840                                   const MemRegion* superRegion,
841                                   ASTContext &Ctx){
842
843  QualType T = Ctx.getCanonicalType(elementType).getUnqualifiedType();
844
845  llvm::FoldingSetNodeID ID;
846  ElementRegion::ProfileRegion(ID, T, Idx, superRegion);
847
848  void *InsertPos;
849  MemRegion* data = Regions.FindNodeOrInsertPos(ID, InsertPos);
850  ElementRegion* R = cast_or_null<ElementRegion>(data);
851
852  if (!R) {
853    R = (ElementRegion*) A.Allocate<ElementRegion>();
854    new (R) ElementRegion(T, Idx, superRegion);
855    Regions.InsertNode(R, InsertPos);
856  }
857
858  return R;
859}
860
861const FunctionTextRegion *
862MemRegionManager::getFunctionTextRegion(const NamedDecl *FD) {
863  return getSubRegion<FunctionTextRegion>(FD, getCodeRegion());
864}
865
866const BlockTextRegion *
867MemRegionManager::getBlockTextRegion(const BlockDecl *BD, CanQualType locTy,
868                                     AnalysisDeclContext *AC) {
869  return getSubRegion<BlockTextRegion>(BD, locTy, AC, getCodeRegion());
870}
871
872
873/// getSymbolicRegion - Retrieve or create a "symbolic" memory region.
874const SymbolicRegion *MemRegionManager::getSymbolicRegion(SymbolRef sym) {
875  return getSubRegion<SymbolicRegion>(sym, getUnknownRegion());
876}
877
878const SymbolicRegion *MemRegionManager::getSymbolicHeapRegion(SymbolRef Sym) {
879  return getSubRegion<SymbolicRegion>(Sym, getHeapRegion());
880}
881
882const FieldRegion*
883MemRegionManager::getFieldRegion(const FieldDecl *d,
884                                 const MemRegion* superRegion){
885  return getSubRegion<FieldRegion>(d, superRegion);
886}
887
888const ObjCIvarRegion*
889MemRegionManager::getObjCIvarRegion(const ObjCIvarDecl *d,
890                                    const MemRegion* superRegion) {
891  return getSubRegion<ObjCIvarRegion>(d, superRegion);
892}
893
894const CXXTempObjectRegion*
895MemRegionManager::getCXXTempObjectRegion(Expr const *E,
896                                         LocationContext const *LC) {
897  const StackFrameContext *SFC = LC->getCurrentStackFrame();
898  assert(SFC);
899  return getSubRegion<CXXTempObjectRegion>(E, getStackLocalsRegion(SFC));
900}
901
902/// Checks whether \p BaseClass is a valid virtual or direct non-virtual base
903/// class of the type of \p Super.
904static bool isValidBaseClass(const CXXRecordDecl *BaseClass,
905                             const TypedValueRegion *Super,
906                             bool IsVirtual) {
907  BaseClass = BaseClass->getCanonicalDecl();
908
909  const CXXRecordDecl *Class = Super->getValueType()->getAsCXXRecordDecl();
910  if (!Class)
911    return true;
912
913  if (IsVirtual)
914    return Class->isVirtuallyDerivedFrom(BaseClass);
915
916  for (CXXRecordDecl::base_class_const_iterator I = Class->bases_begin(),
917                                                E = Class->bases_end();
918       I != E; ++I) {
919    if (I->getType()->getAsCXXRecordDecl()->getCanonicalDecl() == BaseClass)
920      return true;
921  }
922
923  return false;
924}
925
926const CXXBaseObjectRegion *
927MemRegionManager::getCXXBaseObjectRegion(const CXXRecordDecl *RD,
928                                         const MemRegion *Super,
929                                         bool IsVirtual) {
930  if (isa<TypedValueRegion>(Super)) {
931    assert(isValidBaseClass(RD, dyn_cast<TypedValueRegion>(Super), IsVirtual));
932    (void)isValidBaseClass;
933
934    if (IsVirtual) {
935      // Virtual base regions should not be layered, since the layout rules
936      // are different.
937      while (const CXXBaseObjectRegion *Base =
938               dyn_cast<CXXBaseObjectRegion>(Super)) {
939        Super = Base->getSuperRegion();
940      }
941      assert(Super && !isa<MemSpaceRegion>(Super));
942    }
943  }
944
945  return getSubRegion<CXXBaseObjectRegion>(RD, IsVirtual, Super);
946}
947
948const CXXThisRegion*
949MemRegionManager::getCXXThisRegion(QualType thisPointerTy,
950                                   const LocationContext *LC) {
951  const StackFrameContext *STC = LC->getCurrentStackFrame();
952  assert(STC);
953  const PointerType *PT = thisPointerTy->getAs<PointerType>();
954  assert(PT);
955  return getSubRegion<CXXThisRegion>(PT, getStackArgumentsRegion(STC));
956}
957
958const AllocaRegion*
959MemRegionManager::getAllocaRegion(const Expr *E, unsigned cnt,
960                                  const LocationContext *LC) {
961  const StackFrameContext *STC = LC->getCurrentStackFrame();
962  assert(STC);
963  return getSubRegion<AllocaRegion>(E, cnt, getStackLocalsRegion(STC));
964}
965
966const MemSpaceRegion *MemRegion::getMemorySpace() const {
967  const MemRegion *R = this;
968  const SubRegion* SR = dyn_cast<SubRegion>(this);
969
970  while (SR) {
971    R = SR->getSuperRegion();
972    SR = dyn_cast<SubRegion>(R);
973  }
974
975  return dyn_cast<MemSpaceRegion>(R);
976}
977
978bool MemRegion::hasStackStorage() const {
979  return isa<StackSpaceRegion>(getMemorySpace());
980}
981
982bool MemRegion::hasStackNonParametersStorage() const {
983  return isa<StackLocalsSpaceRegion>(getMemorySpace());
984}
985
986bool MemRegion::hasStackParametersStorage() const {
987  return isa<StackArgumentsSpaceRegion>(getMemorySpace());
988}
989
990bool MemRegion::hasGlobalsOrParametersStorage() const {
991  const MemSpaceRegion *MS = getMemorySpace();
992  return isa<StackArgumentsSpaceRegion>(MS) ||
993         isa<GlobalsSpaceRegion>(MS);
994}
995
996// getBaseRegion strips away all elements and fields, and get the base region
997// of them.
998const MemRegion *MemRegion::getBaseRegion() const {
999  const MemRegion *R = this;
1000  while (true) {
1001    switch (R->getKind()) {
1002      case MemRegion::ElementRegionKind:
1003      case MemRegion::FieldRegionKind:
1004      case MemRegion::ObjCIvarRegionKind:
1005      case MemRegion::CXXBaseObjectRegionKind:
1006        R = cast<SubRegion>(R)->getSuperRegion();
1007        continue;
1008      default:
1009        break;
1010    }
1011    break;
1012  }
1013  return R;
1014}
1015
1016bool MemRegion::isSubRegionOf(const MemRegion *R) const {
1017  return false;
1018}
1019
1020//===----------------------------------------------------------------------===//
1021// View handling.
1022//===----------------------------------------------------------------------===//
1023
1024const MemRegion *MemRegion::StripCasts(bool StripBaseCasts) const {
1025  const MemRegion *R = this;
1026  while (true) {
1027    switch (R->getKind()) {
1028    case ElementRegionKind: {
1029      const ElementRegion *ER = cast<ElementRegion>(R);
1030      if (!ER->getIndex().isZeroConstant())
1031        return R;
1032      R = ER->getSuperRegion();
1033      break;
1034    }
1035    case CXXBaseObjectRegionKind:
1036      if (!StripBaseCasts)
1037        return R;
1038      R = cast<CXXBaseObjectRegion>(R)->getSuperRegion();
1039      break;
1040    default:
1041      return R;
1042    }
1043  }
1044}
1045
1046// FIXME: Merge with the implementation of the same method in Store.cpp
1047static bool IsCompleteType(ASTContext &Ctx, QualType Ty) {
1048  if (const RecordType *RT = Ty->getAs<RecordType>()) {
1049    const RecordDecl *D = RT->getDecl();
1050    if (!D->getDefinition())
1051      return false;
1052  }
1053
1054  return true;
1055}
1056
1057RegionRawOffset ElementRegion::getAsArrayOffset() const {
1058  CharUnits offset = CharUnits::Zero();
1059  const ElementRegion *ER = this;
1060  const MemRegion *superR = NULL;
1061  ASTContext &C = getContext();
1062
1063  // FIXME: Handle multi-dimensional arrays.
1064
1065  while (ER) {
1066    superR = ER->getSuperRegion();
1067
1068    // FIXME: generalize to symbolic offsets.
1069    SVal index = ER->getIndex();
1070    if (Optional<nonloc::ConcreteInt> CI = index.getAs<nonloc::ConcreteInt>()) {
1071      // Update the offset.
1072      int64_t i = CI->getValue().getSExtValue();
1073
1074      if (i != 0) {
1075        QualType elemType = ER->getElementType();
1076
1077        // If we are pointing to an incomplete type, go no further.
1078        if (!IsCompleteType(C, elemType)) {
1079          superR = ER;
1080          break;
1081        }
1082
1083        CharUnits size = C.getTypeSizeInChars(elemType);
1084        offset += (i * size);
1085      }
1086
1087      // Go to the next ElementRegion (if any).
1088      ER = dyn_cast<ElementRegion>(superR);
1089      continue;
1090    }
1091
1092    return NULL;
1093  }
1094
1095  assert(superR && "super region cannot be NULL");
1096  return RegionRawOffset(superR, offset);
1097}
1098
1099
1100/// Returns true if \p Base is an immediate base class of \p Child
1101static bool isImmediateBase(const CXXRecordDecl *Child,
1102                            const CXXRecordDecl *Base) {
1103  // Note that we do NOT canonicalize the base class here, because
1104  // ASTRecordLayout doesn't either. If that leads us down the wrong path,
1105  // so be it; at least we won't crash.
1106  for (CXXRecordDecl::base_class_const_iterator I = Child->bases_begin(),
1107                                                E = Child->bases_end();
1108       I != E; ++I) {
1109    if (I->getType()->getAsCXXRecordDecl() == Base)
1110      return true;
1111  }
1112
1113  return false;
1114}
1115
1116RegionOffset MemRegion::getAsOffset() const {
1117  const MemRegion *R = this;
1118  const MemRegion *SymbolicOffsetBase = 0;
1119  int64_t Offset = 0;
1120
1121  while (1) {
1122    switch (R->getKind()) {
1123    case GenericMemSpaceRegionKind:
1124    case StackLocalsSpaceRegionKind:
1125    case StackArgumentsSpaceRegionKind:
1126    case HeapSpaceRegionKind:
1127    case UnknownSpaceRegionKind:
1128    case StaticGlobalSpaceRegionKind:
1129    case GlobalInternalSpaceRegionKind:
1130    case GlobalSystemSpaceRegionKind:
1131    case GlobalImmutableSpaceRegionKind:
1132      // Stores can bind directly to a region space to set a default value.
1133      assert(Offset == 0 && !SymbolicOffsetBase);
1134      goto Finish;
1135
1136    case FunctionTextRegionKind:
1137    case BlockTextRegionKind:
1138    case BlockDataRegionKind:
1139      // These will never have bindings, but may end up having values requested
1140      // if the user does some strange casting.
1141      if (Offset != 0)
1142        SymbolicOffsetBase = R;
1143      goto Finish;
1144
1145    case SymbolicRegionKind:
1146    case AllocaRegionKind:
1147    case CompoundLiteralRegionKind:
1148    case CXXThisRegionKind:
1149    case StringRegionKind:
1150    case ObjCStringRegionKind:
1151    case VarRegionKind:
1152    case CXXTempObjectRegionKind:
1153      // Usual base regions.
1154      goto Finish;
1155
1156    case ObjCIvarRegionKind:
1157      // This is a little strange, but it's a compromise between
1158      // ObjCIvarRegions having unknown compile-time offsets (when using the
1159      // non-fragile runtime) and yet still being distinct, non-overlapping
1160      // regions. Thus we treat them as "like" base regions for the purposes
1161      // of computing offsets.
1162      goto Finish;
1163
1164    case CXXBaseObjectRegionKind: {
1165      const CXXBaseObjectRegion *BOR = cast<CXXBaseObjectRegion>(R);
1166      R = BOR->getSuperRegion();
1167
1168      QualType Ty;
1169      bool RootIsSymbolic = false;
1170      if (const TypedValueRegion *TVR = dyn_cast<TypedValueRegion>(R)) {
1171        Ty = TVR->getDesugaredValueType(getContext());
1172      } else if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) {
1173        // If our base region is symbolic, we don't know what type it really is.
1174        // Pretend the type of the symbol is the true dynamic type.
1175        // (This will at least be self-consistent for the life of the symbol.)
1176        Ty = SR->getSymbol()->getType()->getPointeeType();
1177        RootIsSymbolic = true;
1178      }
1179
1180      const CXXRecordDecl *Child = Ty->getAsCXXRecordDecl();
1181      if (!Child) {
1182        // We cannot compute the offset of the base class.
1183        SymbolicOffsetBase = R;
1184      }
1185
1186      if (RootIsSymbolic) {
1187        // Base layers on symbolic regions may not be type-correct.
1188        // Double-check the inheritance here, and revert to a symbolic offset
1189        // if it's invalid (e.g. due to a reinterpret_cast).
1190        if (BOR->isVirtual()) {
1191          if (!Child->isVirtuallyDerivedFrom(BOR->getDecl()))
1192            SymbolicOffsetBase = R;
1193        } else {
1194          if (!isImmediateBase(Child, BOR->getDecl()))
1195            SymbolicOffsetBase = R;
1196        }
1197      }
1198
1199      // Don't bother calculating precise offsets if we already have a
1200      // symbolic offset somewhere in the chain.
1201      if (SymbolicOffsetBase)
1202        continue;
1203
1204      CharUnits BaseOffset;
1205      const ASTRecordLayout &Layout = getContext().getASTRecordLayout(Child);
1206      if (BOR->isVirtual())
1207        BaseOffset = Layout.getVBaseClassOffset(BOR->getDecl());
1208      else
1209        BaseOffset = Layout.getBaseClassOffset(BOR->getDecl());
1210
1211      // The base offset is in chars, not in bits.
1212      Offset += BaseOffset.getQuantity() * getContext().getCharWidth();
1213      break;
1214    }
1215    case ElementRegionKind: {
1216      const ElementRegion *ER = cast<ElementRegion>(R);
1217      R = ER->getSuperRegion();
1218
1219      QualType EleTy = ER->getValueType();
1220      if (!IsCompleteType(getContext(), EleTy)) {
1221        // We cannot compute the offset of the base class.
1222        SymbolicOffsetBase = R;
1223        continue;
1224      }
1225
1226      SVal Index = ER->getIndex();
1227      if (Optional<nonloc::ConcreteInt> CI =
1228              Index.getAs<nonloc::ConcreteInt>()) {
1229        // Don't bother calculating precise offsets if we already have a
1230        // symbolic offset somewhere in the chain.
1231        if (SymbolicOffsetBase)
1232          continue;
1233
1234        int64_t i = CI->getValue().getSExtValue();
1235        // This type size is in bits.
1236        Offset += i * getContext().getTypeSize(EleTy);
1237      } else {
1238        // We cannot compute offset for non-concrete index.
1239        SymbolicOffsetBase = R;
1240      }
1241      break;
1242    }
1243    case FieldRegionKind: {
1244      const FieldRegion *FR = cast<FieldRegion>(R);
1245      R = FR->getSuperRegion();
1246
1247      const RecordDecl *RD = FR->getDecl()->getParent();
1248      if (RD->isUnion() || !RD->isCompleteDefinition()) {
1249        // We cannot compute offset for incomplete type.
1250        // For unions, we could treat everything as offset 0, but we'd rather
1251        // treat each field as a symbolic offset so they aren't stored on top
1252        // of each other, since we depend on things in typed regions actually
1253        // matching their types.
1254        SymbolicOffsetBase = R;
1255      }
1256
1257      // Don't bother calculating precise offsets if we already have a
1258      // symbolic offset somewhere in the chain.
1259      if (SymbolicOffsetBase)
1260        continue;
1261
1262      // Get the field number.
1263      unsigned idx = 0;
1264      for (RecordDecl::field_iterator FI = RD->field_begin(),
1265             FE = RD->field_end(); FI != FE; ++FI, ++idx)
1266        if (FR->getDecl() == *FI)
1267          break;
1268
1269      const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
1270      // This is offset in bits.
1271      Offset += Layout.getFieldOffset(idx);
1272      break;
1273    }
1274    }
1275  }
1276
1277 Finish:
1278  if (SymbolicOffsetBase)
1279    return RegionOffset(SymbolicOffsetBase, RegionOffset::Symbolic);
1280  return RegionOffset(R, Offset);
1281}
1282
1283//===----------------------------------------------------------------------===//
1284// BlockDataRegion
1285//===----------------------------------------------------------------------===//
1286
1287std::pair<const VarRegion *, const VarRegion *>
1288BlockDataRegion::getCaptureRegions(const VarDecl *VD) {
1289  MemRegionManager &MemMgr = *getMemRegionManager();
1290  const VarRegion *VR = 0;
1291  const VarRegion *OriginalVR = 0;
1292
1293  if (!VD->getAttr<BlocksAttr>() && VD->hasLocalStorage()) {
1294    VR = MemMgr.getVarRegion(VD, this);
1295    OriginalVR = MemMgr.getVarRegion(VD, LC);
1296  }
1297  else {
1298    if (LC) {
1299      VR = MemMgr.getVarRegion(VD, LC);
1300      OriginalVR = VR;
1301    }
1302    else {
1303      VR = MemMgr.getVarRegion(VD, MemMgr.getUnknownRegion());
1304      OriginalVR = MemMgr.getVarRegion(VD, LC);
1305    }
1306  }
1307  return std::make_pair(VR, OriginalVR);
1308}
1309
1310void BlockDataRegion::LazyInitializeReferencedVars() {
1311  if (ReferencedVars)
1312    return;
1313
1314  AnalysisDeclContext *AC = getCodeRegion()->getAnalysisDeclContext();
1315  AnalysisDeclContext::referenced_decls_iterator I, E;
1316  llvm::tie(I, E) = AC->getReferencedBlockVars(BC->getDecl());
1317
1318  if (I == E) {
1319    ReferencedVars = (void*) 0x1;
1320    return;
1321  }
1322
1323  MemRegionManager &MemMgr = *getMemRegionManager();
1324  llvm::BumpPtrAllocator &A = MemMgr.getAllocator();
1325  BumpVectorContext BC(A);
1326
1327  typedef BumpVector<const MemRegion*> VarVec;
1328  VarVec *BV = (VarVec*) A.Allocate<VarVec>();
1329  new (BV) VarVec(BC, E - I);
1330  VarVec *BVOriginal = (VarVec*) A.Allocate<VarVec>();
1331  new (BVOriginal) VarVec(BC, E - I);
1332
1333  for ( ; I != E; ++I) {
1334    const VarRegion *VR = 0;
1335    const VarRegion *OriginalVR = 0;
1336    llvm::tie(VR, OriginalVR) = getCaptureRegions(*I);
1337    assert(VR);
1338    assert(OriginalVR);
1339    BV->push_back(VR, BC);
1340    BVOriginal->push_back(OriginalVR, BC);
1341  }
1342
1343  ReferencedVars = BV;
1344  OriginalVars = BVOriginal;
1345}
1346
1347BlockDataRegion::referenced_vars_iterator
1348BlockDataRegion::referenced_vars_begin() const {
1349  const_cast<BlockDataRegion*>(this)->LazyInitializeReferencedVars();
1350
1351  BumpVector<const MemRegion*> *Vec =
1352    static_cast<BumpVector<const MemRegion*>*>(ReferencedVars);
1353
1354  if (Vec == (void*) 0x1)
1355    return BlockDataRegion::referenced_vars_iterator(0, 0);
1356
1357  BumpVector<const MemRegion*> *VecOriginal =
1358    static_cast<BumpVector<const MemRegion*>*>(OriginalVars);
1359
1360  return BlockDataRegion::referenced_vars_iterator(Vec->begin(),
1361                                                   VecOriginal->begin());
1362}
1363
1364BlockDataRegion::referenced_vars_iterator
1365BlockDataRegion::referenced_vars_end() const {
1366  const_cast<BlockDataRegion*>(this)->LazyInitializeReferencedVars();
1367
1368  BumpVector<const MemRegion*> *Vec =
1369    static_cast<BumpVector<const MemRegion*>*>(ReferencedVars);
1370
1371  if (Vec == (void*) 0x1)
1372    return BlockDataRegion::referenced_vars_iterator(0, 0);
1373
1374  BumpVector<const MemRegion*> *VecOriginal =
1375    static_cast<BumpVector<const MemRegion*>*>(OriginalVars);
1376
1377  return BlockDataRegion::referenced_vars_iterator(Vec->end(),
1378                                                   VecOriginal->end());
1379}
1380
1381const VarRegion *BlockDataRegion::getOriginalRegion(const VarRegion *R) const {
1382  for (referenced_vars_iterator I = referenced_vars_begin(),
1383                                E = referenced_vars_end();
1384       I != E; ++I) {
1385    if (I.getCapturedRegion() == R)
1386      return I.getOriginalRegion();
1387  }
1388  return 0;
1389}
1390