xref: /trueos/contrib/llvm/tools/clang/lib/StaticAnalyzer/Core/MemRegion.cpp (revision 9cedb8bb69b89b0f0c529937247a6a80cabdbaec) 
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 
27 using namespace clang;
28 using namespace ento;
29 
30 //===----------------------------------------------------------------------===//
31 // MemRegion Construction.
32 //===----------------------------------------------------------------------===//
33 
34 template<typename RegionTy> struct MemRegionManagerTrait;
35 
36 template <typename RegionTy, typename A1>
37 RegionTy* 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 
57 template <typename RegionTy, typename A1>
58 RegionTy* 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 
75 template <typename RegionTy, typename A1, typename A2>
76 RegionTy* 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 
96 template <typename RegionTy, typename A1, typename A2>
97 RegionTy* 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 
115 template <typename RegionTy, typename A1, typename A2, typename A3>
116 RegionTy* 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 
~MemRegion()138 MemRegion::~MemRegion() {}
139 
~MemRegionManager()140 MemRegionManager::~MemRegionManager() {
141   // All regions and their data are BumpPtrAllocated.  No need to call
142   // their destructors.
143 }
144 
145 //===----------------------------------------------------------------------===//
146 // Basic methods.
147 //===----------------------------------------------------------------------===//
148 
isSubRegionOf(const MemRegion * R) const149 bool 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 
getMemRegionManager() const162 MemRegionManager* 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 
getStackFrame() const174 const 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 
getExtent(SValBuilder & svalBuilder) const183 DefinedOrUnknownSVal 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 
getExtent(SValBuilder & svalBuilder) const197 DefinedOrUnknownSVal 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 
getExtent(SValBuilder & svalBuilder) const216 DefinedOrUnknownSVal AllocaRegion::getExtent(SValBuilder &svalBuilder) const {
217   return nonloc::SymbolVal(svalBuilder.getSymbolManager().getExtentSymbol(this));
218 }
219 
getExtent(SValBuilder & svalBuilder) const220 DefinedOrUnknownSVal SymbolicRegion::getExtent(SValBuilder &svalBuilder) const {
221   return nonloc::SymbolVal(svalBuilder.getSymbolManager().getExtentSymbol(this));
222 }
223 
getExtent(SValBuilder & svalBuilder) const224 DefinedOrUnknownSVal StringRegion::getExtent(SValBuilder &svalBuilder) const {
225   return svalBuilder.makeIntVal(getStringLiteral()->getByteLength()+1,
226                                 svalBuilder.getArrayIndexType());
227 }
228 
ObjCIvarRegion(const ObjCIvarDecl * ivd,const MemRegion * sReg)229 ObjCIvarRegion::ObjCIvarRegion(const ObjCIvarDecl *ivd, const MemRegion* sReg)
230   : DeclRegion(ivd, sReg, ObjCIvarRegionKind) {}
231 
getDecl() const232 const ObjCIvarDecl *ObjCIvarRegion::getDecl() const {
233   return cast<ObjCIvarDecl>(D);
234 }
235 
getValueType() const236 QualType ObjCIvarRegion::getValueType() const {
237   return getDecl()->getType();
238 }
239 
getValueType() const240 QualType CXXBaseObjectRegion::getValueType() const {
241   return QualType(getDecl()->getTypeForDecl(), 0);
242 }
243 
244 //===----------------------------------------------------------------------===//
245 // FoldingSet profiling.
246 //===----------------------------------------------------------------------===//
247 
Profile(llvm::FoldingSetNodeID & ID) const248 void MemSpaceRegion::Profile(llvm::FoldingSetNodeID& ID) const {
249   ID.AddInteger((unsigned)getKind());
250 }
251 
Profile(llvm::FoldingSetNodeID & ID) const252 void StackSpaceRegion::Profile(llvm::FoldingSetNodeID &ID) const {
253   ID.AddInteger((unsigned)getKind());
254   ID.AddPointer(getStackFrame());
255 }
256 
Profile(llvm::FoldingSetNodeID & ID) const257 void StaticGlobalSpaceRegion::Profile(llvm::FoldingSetNodeID &ID) const {
258   ID.AddInteger((unsigned)getKind());
259   ID.AddPointer(getCodeRegion());
260 }
261 
ProfileRegion(llvm::FoldingSetNodeID & ID,const StringLiteral * Str,const MemRegion * superRegion)262 void 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 
ProfileRegion(llvm::FoldingSetNodeID & ID,const ObjCStringLiteral * Str,const MemRegion * superRegion)270 void 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 
ProfileRegion(llvm::FoldingSetNodeID & ID,const Expr * Ex,unsigned cnt,const MemRegion * superRegion)278 void 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 
Profile(llvm::FoldingSetNodeID & ID) const287 void AllocaRegion::Profile(llvm::FoldingSetNodeID& ID) const {
288   ProfileRegion(ID, Ex, Cnt, superRegion);
289 }
290 
Profile(llvm::FoldingSetNodeID & ID) const291 void CompoundLiteralRegion::Profile(llvm::FoldingSetNodeID& ID) const {
292   CompoundLiteralRegion::ProfileRegion(ID, CL, superRegion);
293 }
294 
ProfileRegion(llvm::FoldingSetNodeID & ID,const CompoundLiteralExpr * CL,const MemRegion * superRegion)295 void 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 
ProfileRegion(llvm::FoldingSetNodeID & ID,const PointerType * PT,const MemRegion * sRegion)303 void 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 
Profile(llvm::FoldingSetNodeID & ID) const311 void CXXThisRegion::Profile(llvm::FoldingSetNodeID &ID) const {
312   CXXThisRegion::ProfileRegion(ID, ThisPointerTy, superRegion);
313 }
314 
ProfileRegion(llvm::FoldingSetNodeID & ID,const ObjCIvarDecl * ivd,const MemRegion * superRegion)315 void ObjCIvarRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
316                                    const ObjCIvarDecl *ivd,
317                                    const MemRegion* superRegion) {
318   DeclRegion::ProfileRegion(ID, ivd, superRegion, ObjCIvarRegionKind);
319 }
320 
ProfileRegion(llvm::FoldingSetNodeID & ID,const Decl * D,const MemRegion * superRegion,Kind k)321 void 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 
Profile(llvm::FoldingSetNodeID & ID) const328 void DeclRegion::Profile(llvm::FoldingSetNodeID& ID) const {
329   DeclRegion::ProfileRegion(ID, D, superRegion, getKind());
330 }
331 
Profile(llvm::FoldingSetNodeID & ID) const332 void VarRegion::Profile(llvm::FoldingSetNodeID &ID) const {
333   VarRegion::ProfileRegion(ID, getDecl(), superRegion);
334 }
335 
ProfileRegion(llvm::FoldingSetNodeID & ID,SymbolRef sym,const MemRegion * sreg)336 void 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 
Profile(llvm::FoldingSetNodeID & ID) const343 void SymbolicRegion::Profile(llvm::FoldingSetNodeID& ID) const {
344   SymbolicRegion::ProfileRegion(ID, sym, getSuperRegion());
345 }
346 
ProfileRegion(llvm::FoldingSetNodeID & ID,QualType ElementType,SVal Idx,const MemRegion * superRegion)347 void 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 
Profile(llvm::FoldingSetNodeID & ID) const356 void ElementRegion::Profile(llvm::FoldingSetNodeID& ID) const {
357   ElementRegion::ProfileRegion(ID, ElementType, Index, superRegion);
358 }
359 
ProfileRegion(llvm::FoldingSetNodeID & ID,const NamedDecl * FD,const MemRegion *)360 void FunctionTextRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
361                                        const NamedDecl *FD,
362                                        const MemRegion*) {
363   ID.AddInteger(MemRegion::FunctionTextRegionKind);
364   ID.AddPointer(FD);
365 }
366 
Profile(llvm::FoldingSetNodeID & ID) const367 void FunctionTextRegion::Profile(llvm::FoldingSetNodeID& ID) const {
368   FunctionTextRegion::ProfileRegion(ID, FD, superRegion);
369 }
370 
ProfileRegion(llvm::FoldingSetNodeID & ID,const BlockDecl * BD,CanQualType,const AnalysisDeclContext * AC,const MemRegion *)371 void 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 
Profile(llvm::FoldingSetNodeID & ID) const379 void BlockTextRegion::Profile(llvm::FoldingSetNodeID& ID) const {
380   BlockTextRegion::ProfileRegion(ID, BD, locTy, AC, superRegion);
381 }
382 
ProfileRegion(llvm::FoldingSetNodeID & ID,const BlockTextRegion * BC,const LocationContext * LC,unsigned BlkCount,const MemRegion * sReg)383 void 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 
Profile(llvm::FoldingSetNodeID & ID) const395 void BlockDataRegion::Profile(llvm::FoldingSetNodeID& ID) const {
396   BlockDataRegion::ProfileRegion(ID, BC, LC, BlockCount, getSuperRegion());
397 }
398 
ProfileRegion(llvm::FoldingSetNodeID & ID,Expr const * Ex,const MemRegion * sReg)399 void CXXTempObjectRegion::ProfileRegion(llvm::FoldingSetNodeID &ID,
400                                         Expr const *Ex,
401                                         const MemRegion *sReg) {
402   ID.AddPointer(Ex);
403   ID.AddPointer(sReg);
404 }
405 
Profile(llvm::FoldingSetNodeID & ID) const406 void CXXTempObjectRegion::Profile(llvm::FoldingSetNodeID &ID) const {
407   ProfileRegion(ID, Ex, getSuperRegion());
408 }
409 
ProfileRegion(llvm::FoldingSetNodeID & ID,const CXXRecordDecl * RD,bool IsVirtual,const MemRegion * SReg)410 void 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 
Profile(llvm::FoldingSetNodeID & ID) const419 void CXXBaseObjectRegion::Profile(llvm::FoldingSetNodeID &ID) const {
420   ProfileRegion(ID, getDecl(), isVirtual(), superRegion);
421 }
422 
423 //===----------------------------------------------------------------------===//
424 // Region anchors.
425 //===----------------------------------------------------------------------===//
426 
anchor()427 void GlobalsSpaceRegion::anchor() { }
anchor()428 void HeapSpaceRegion::anchor() { }
anchor()429 void UnknownSpaceRegion::anchor() { }
anchor()430 void StackLocalsSpaceRegion::anchor() { }
anchor()431 void StackArgumentsSpaceRegion::anchor() { }
anchor()432 void TypedRegion::anchor() { }
anchor()433 void TypedValueRegion::anchor() { }
anchor()434 void CodeTextRegion::anchor() { }
anchor()435 void SubRegion::anchor() { }
436 
437 //===----------------------------------------------------------------------===//
438 // Region pretty-printing.
439 //===----------------------------------------------------------------------===//
440 
dump() const441 void MemRegion::dump() const {
442   dumpToStream(llvm::errs());
443 }
444 
getString() const445 std::string MemRegion::getString() const {
446   std::string s;
447   llvm::raw_string_ostream os(s);
448   dumpToStream(os);
449   return os.str();
450 }
451 
dumpToStream(raw_ostream & os) const452 void MemRegion::dumpToStream(raw_ostream &os) const {
453   os << "<Unknown Region>";
454 }
455 
dumpToStream(raw_ostream & os) const456 void AllocaRegion::dumpToStream(raw_ostream &os) const {
457   os << "alloca{" << (const void*) Ex << ',' << Cnt << '}';
458 }
459 
dumpToStream(raw_ostream & os) const460 void FunctionTextRegion::dumpToStream(raw_ostream &os) const {
461   os << "code{" << getDecl()->getDeclName().getAsString() << '}';
462 }
463 
dumpToStream(raw_ostream & os) const464 void BlockTextRegion::dumpToStream(raw_ostream &os) const {
465   os << "block_code{" << (const void*) this << '}';
466 }
467 
dumpToStream(raw_ostream & os) const468 void 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 
dumpToStream(raw_ostream & os) const479 void CompoundLiteralRegion::dumpToStream(raw_ostream &os) const {
480   // FIXME: More elaborate pretty-printing.
481   os << "{ " << (const void*) CL <<  " }";
482 }
483 
dumpToStream(raw_ostream & os) const484 void CXXTempObjectRegion::dumpToStream(raw_ostream &os) const {
485   os << "temp_object{" << getValueType().getAsString() << ','
486      << (const void*) Ex << '}';
487 }
488 
dumpToStream(raw_ostream & os) const489 void CXXBaseObjectRegion::dumpToStream(raw_ostream &os) const {
490   os << "base{" << superRegion << ',' << getDecl()->getName() << '}';
491 }
492 
dumpToStream(raw_ostream & os) const493 void CXXThisRegion::dumpToStream(raw_ostream &os) const {
494   os << "this";
495 }
496 
dumpToStream(raw_ostream & os) const497 void ElementRegion::dumpToStream(raw_ostream &os) const {
498   os << "element{" << superRegion << ','
499      << Index << ',' << getElementType().getAsString() << '}';
500 }
501 
dumpToStream(raw_ostream & os) const502 void FieldRegion::dumpToStream(raw_ostream &os) const {
503   os << superRegion << "->" << *getDecl();
504 }
505 
dumpToStream(raw_ostream & os) const506 void ObjCIvarRegion::dumpToStream(raw_ostream &os) const {
507   os << "ivar{" << superRegion << ',' << *getDecl() << '}';
508 }
509 
dumpToStream(raw_ostream & os) const510 void StringRegion::dumpToStream(raw_ostream &os) const {
511   Str->printPretty(os, 0, PrintingPolicy(getContext().getLangOpts()));
512 }
513 
dumpToStream(raw_ostream & os) const514 void ObjCStringRegion::dumpToStream(raw_ostream &os) const {
515   Str->printPretty(os, 0, PrintingPolicy(getContext().getLangOpts()));
516 }
517 
dumpToStream(raw_ostream & os) const518 void SymbolicRegion::dumpToStream(raw_ostream &os) const {
519   os << "SymRegion{" << sym << '}';
520 }
521 
dumpToStream(raw_ostream & os) const522 void VarRegion::dumpToStream(raw_ostream &os) const {
523   os << *cast<VarDecl>(D);
524 }
525 
dump() const526 void RegionRawOffset::dump() const {
527   dumpToStream(llvm::errs());
528 }
529 
dumpToStream(raw_ostream & os) const530 void RegionRawOffset::dumpToStream(raw_ostream &os) const {
531   os << "raw_offset{" << getRegion() << ',' << getOffset().getQuantity() << '}';
532 }
533 
dumpToStream(raw_ostream & os) const534 void StaticGlobalSpaceRegion::dumpToStream(raw_ostream &os) const {
535   os << "StaticGlobalsMemSpace{" << CR << '}';
536 }
537 
dumpToStream(raw_ostream & os) const538 void GlobalInternalSpaceRegion::dumpToStream(raw_ostream &os) const {
539   os << "GlobalInternalSpaceRegion";
540 }
541 
dumpToStream(raw_ostream & os) const542 void GlobalSystemSpaceRegion::dumpToStream(raw_ostream &os) const {
543   os << "GlobalSystemSpaceRegion";
544 }
545 
dumpToStream(raw_ostream & os) const546 void GlobalImmutableSpaceRegion::dumpToStream(raw_ostream &os) const {
547   os << "GlobalImmutableSpaceRegion";
548 }
549 
dumpToStream(raw_ostream & os) const550 void HeapSpaceRegion::dumpToStream(raw_ostream &os) const {
551   os << "HeapSpaceRegion";
552 }
553 
dumpToStream(raw_ostream & os) const554 void UnknownSpaceRegion::dumpToStream(raw_ostream &os) const {
555   os << "UnknownSpaceRegion";
556 }
557 
dumpToStream(raw_ostream & os) const558 void StackArgumentsSpaceRegion::dumpToStream(raw_ostream &os) const {
559   os << "StackArgumentsSpaceRegion";
560 }
561 
dumpToStream(raw_ostream & os) const562 void StackLocalsSpaceRegion::dumpToStream(raw_ostream &os) const {
563   os << "StackLocalsSpaceRegion";
564 }
565 
canPrintPretty() const566 bool MemRegion::canPrintPretty() const {
567   return canPrintPrettyAsExpr();
568 }
569 
canPrintPrettyAsExpr() const570 bool MemRegion::canPrintPrettyAsExpr() const {
571   return false;
572 }
573 
printPretty(raw_ostream & os) const574 void 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 
printPrettyAsExpr(raw_ostream & os) const582 void MemRegion::printPrettyAsExpr(raw_ostream &os) const {
583   llvm_unreachable("This region cannot be printed pretty.");
584   return;
585 }
586 
canPrintPrettyAsExpr() const587 bool VarRegion::canPrintPrettyAsExpr() const {
588   return true;
589 }
590 
printPrettyAsExpr(raw_ostream & os) const591 void VarRegion::printPrettyAsExpr(raw_ostream &os) const {
592   os << getDecl()->getName();
593 }
594 
canPrintPrettyAsExpr() const595 bool ObjCIvarRegion::canPrintPrettyAsExpr() const {
596   return true;
597 }
598 
printPrettyAsExpr(raw_ostream & os) const599 void ObjCIvarRegion::printPrettyAsExpr(raw_ostream &os) const {
600   os << getDecl()->getName();
601 }
602 
canPrintPretty() const603 bool FieldRegion::canPrintPretty() const {
604   return true;
605 }
606 
canPrintPrettyAsExpr() const607 bool FieldRegion::canPrintPrettyAsExpr() const {
608   return superRegion->canPrintPrettyAsExpr();
609 }
610 
printPrettyAsExpr(raw_ostream & os) const611 void FieldRegion::printPrettyAsExpr(raw_ostream &os) const {
612   assert(canPrintPrettyAsExpr());
613   superRegion->printPrettyAsExpr(os);
614   os << "." << getDecl()->getName();
615 }
616 
printPretty(raw_ostream & os) const617 void 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 
canPrintPrettyAsExpr() const628 bool CXXBaseObjectRegion::canPrintPrettyAsExpr() const {
629   return superRegion->canPrintPrettyAsExpr();
630 }
631 
printPrettyAsExpr(raw_ostream & os) const632 void CXXBaseObjectRegion::printPrettyAsExpr(raw_ostream &os) const {
633   superRegion->printPrettyAsExpr(os);
634 }
635 
636 //===----------------------------------------------------------------------===//
637 // MemRegionManager methods.
638 //===----------------------------------------------------------------------===//
639 
640 template <typename REG>
LazyAllocate(REG * & region)641 const 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 
650 template <typename REG, typename ARG>
LazyAllocate(REG * & region,ARG a)651 const 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 
660 const StackLocalsSpaceRegion*
getStackLocalsRegion(const StackFrameContext * STC)661 MemRegionManager::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 
673 const StackArgumentsSpaceRegion *
getStackArgumentsRegion(const StackFrameContext * STC)674 MemRegionManager::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 
686 const GlobalsSpaceRegion
getGlobalsRegion(MemRegion::Kind K,const CodeTextRegion * CR)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 
getHeapRegion()708 const HeapSpaceRegion *MemRegionManager::getHeapRegion() {
709   return LazyAllocate(heap);
710 }
711 
getUnknownRegion()712 const MemSpaceRegion *MemRegionManager::getUnknownRegion() {
713   return LazyAllocate(unknown);
714 }
715 
getCodeRegion()716 const MemSpaceRegion *MemRegionManager::getCodeRegion() {
717   return LazyAllocate(code);
718 }
719 
720 //===----------------------------------------------------------------------===//
721 // Constructing regions.
722 //===----------------------------------------------------------------------===//
getStringRegion(const StringLiteral * Str)723 const StringRegion* MemRegionManager::getStringRegion(const StringLiteral* Str){
724   return getSubRegion<StringRegion>(Str, getGlobalsRegion());
725 }
726 
727 const ObjCStringRegion *
getObjCStringRegion(const ObjCStringLiteral * Str)728 MemRegionManager::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.
735 static llvm::PointerUnion<const StackFrameContext *, const VarRegion *>
getStackOrCaptureRegionForDeclContext(const LocationContext * LC,const DeclContext * DC,const VarDecl * VD)736 getStackOrCaptureRegionForDeclContext(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 
getVarRegion(const VarDecl * D,const LocationContext * LC)763 const 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 
getVarRegion(const VarDecl * D,const MemRegion * superR)844 const VarRegion *MemRegionManager::getVarRegion(const VarDecl *D,
845                                                 const MemRegion *superR) {
846   return getSubRegion<VarRegion>(D, superR);
847 }
848 
849 const BlockDataRegion *
getBlockDataRegion(const BlockTextRegion * BC,const LocationContext * LC,unsigned blockCount)850 MemRegionManager::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 
877 const CXXTempObjectRegion *
getCXXStaticTempObjectRegion(const Expr * Ex)878 MemRegionManager::getCXXStaticTempObjectRegion(const Expr *Ex) {
879   return getSubRegion<CXXTempObjectRegion>(
880       Ex, getGlobalsRegion(MemRegion::GlobalInternalSpaceRegionKind, NULL));
881 }
882 
883 const CompoundLiteralRegion*
getCompoundLiteralRegion(const CompoundLiteralExpr * CL,const LocationContext * LC)884 MemRegionManager::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 
900 const ElementRegion*
getElementRegion(QualType elementType,NonLoc Idx,const MemRegion * superRegion,ASTContext & Ctx)901 MemRegionManager::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 
923 const FunctionTextRegion *
getFunctionTextRegion(const NamedDecl * FD)924 MemRegionManager::getFunctionTextRegion(const NamedDecl *FD) {
925   return getSubRegion<FunctionTextRegion>(FD, getCodeRegion());
926 }
927 
928 const BlockTextRegion *
getBlockTextRegion(const BlockDecl * BD,CanQualType locTy,AnalysisDeclContext * AC)929 MemRegionManager::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.
getSymbolicRegion(SymbolRef sym)936 const SymbolicRegion *MemRegionManager::getSymbolicRegion(SymbolRef sym) {
937   return getSubRegion<SymbolicRegion>(sym, getUnknownRegion());
938 }
939 
getSymbolicHeapRegion(SymbolRef Sym)940 const SymbolicRegion *MemRegionManager::getSymbolicHeapRegion(SymbolRef Sym) {
941   return getSubRegion<SymbolicRegion>(Sym, getHeapRegion());
942 }
943 
944 const FieldRegion*
getFieldRegion(const FieldDecl * d,const MemRegion * superRegion)945 MemRegionManager::getFieldRegion(const FieldDecl *d,
946                                  const MemRegion* superRegion){
947   return getSubRegion<FieldRegion>(d, superRegion);
948 }
949 
950 const ObjCIvarRegion*
getObjCIvarRegion(const ObjCIvarDecl * d,const MemRegion * superRegion)951 MemRegionManager::getObjCIvarRegion(const ObjCIvarDecl *d,
952                                     const MemRegion* superRegion) {
953   return getSubRegion<ObjCIvarRegion>(d, superRegion);
954 }
955 
956 const CXXTempObjectRegion*
getCXXTempObjectRegion(Expr const * E,LocationContext const * LC)957 MemRegionManager::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.
isValidBaseClass(const CXXRecordDecl * BaseClass,const TypedValueRegion * Super,bool IsVirtual)966 static 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 
988 const CXXBaseObjectRegion *
getCXXBaseObjectRegion(const CXXRecordDecl * RD,const MemRegion * Super,bool IsVirtual)989 MemRegionManager::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 
1010 const CXXThisRegion*
getCXXThisRegion(QualType thisPointerTy,const LocationContext * LC)1011 MemRegionManager::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 
1020 const AllocaRegion*
getAllocaRegion(const Expr * E,unsigned cnt,const LocationContext * LC)1021 MemRegionManager::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 
getMemorySpace() const1028 const 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 
hasStackStorage() const1040 bool MemRegion::hasStackStorage() const {
1041   return isa<StackSpaceRegion>(getMemorySpace());
1042 }
1043 
hasStackNonParametersStorage() const1044 bool MemRegion::hasStackNonParametersStorage() const {
1045   return isa<StackLocalsSpaceRegion>(getMemorySpace());
1046 }
1047 
hasStackParametersStorage() const1048 bool MemRegion::hasStackParametersStorage() const {
1049   return isa<StackArgumentsSpaceRegion>(getMemorySpace());
1050 }
1051 
hasGlobalsOrParametersStorage() const1052 bool 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.
getBaseRegion() const1060 const 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 
isSubRegionOf(const MemRegion * R) const1078 bool MemRegion::isSubRegionOf(const MemRegion *R) const {
1079   return false;
1080 }
1081 
1082 //===----------------------------------------------------------------------===//
1083 // View handling.
1084 //===----------------------------------------------------------------------===//
1085 
StripCasts(bool StripBaseCasts) const1086 const 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 
getSymbolicBase() const1108 const 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
IsCompleteType(ASTContext & Ctx,QualType Ty)1120 static 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 
getAsArrayOffset() const1130 RegionRawOffset 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
isImmediateBase(const CXXRecordDecl * Child,const CXXRecordDecl * Base)1174 static 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 
getAsOffset() const1189 RegionOffset 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 
1360 std::pair<const VarRegion *, const VarRegion *>
getCaptureRegions(const VarDecl * VD)1361 BlockDataRegion::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 
LazyInitializeReferencedVars()1383 void 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 
1420 BlockDataRegion::referenced_vars_iterator
referenced_vars_begin() const1421 BlockDataRegion::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 
1437 BlockDataRegion::referenced_vars_iterator
referenced_vars_end() const1438 BlockDataRegion::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 
getOriginalRegion(const VarRegion * R) const1454 const 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 
setTrait(SymbolRef Sym,InvalidationKinds IK)1468 void RegionAndSymbolInvalidationTraits::setTrait(SymbolRef Sym,
1469                                                  InvalidationKinds IK) {
1470   SymTraitsMap[Sym] |= IK;
1471 }
1472 
setTrait(const MemRegion * MR,InvalidationKinds IK)1473 void 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 
hasTrait(SymbolRef Sym,InvalidationKinds IK)1482 bool 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 
hasTrait(const MemRegion * MR,InvalidationKinds IK)1491 bool 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