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>
getRegion(const A1 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>
getSubRegion(const A1 a1,const MemRegion * superRegion)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>
getRegion(const A1 a1,const A2 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>
getSubRegion(const A1 a1,const A2 a2,const MemRegion * superRegion)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>
getSubRegion(const A1 a1,const A2 a2,const A3 a3,const MemRegion * superRegion)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,const MemRegion * sReg)383 void 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
Profile(llvm::FoldingSetNodeID & ID) const393 void BlockDataRegion::Profile(llvm::FoldingSetNodeID& ID) const {
394 BlockDataRegion::ProfileRegion(ID, BC, LC, getSuperRegion());
395 }
396
ProfileRegion(llvm::FoldingSetNodeID & ID,Expr const * Ex,const MemRegion * sReg)397 void CXXTempObjectRegion::ProfileRegion(llvm::FoldingSetNodeID &ID,
398 Expr const *Ex,
399 const MemRegion *sReg) {
400 ID.AddPointer(Ex);
401 ID.AddPointer(sReg);
402 }
403
Profile(llvm::FoldingSetNodeID & ID) const404 void CXXTempObjectRegion::Profile(llvm::FoldingSetNodeID &ID) const {
405 ProfileRegion(ID, Ex, getSuperRegion());
406 }
407
ProfileRegion(llvm::FoldingSetNodeID & ID,const CXXRecordDecl * RD,bool IsVirtual,const MemRegion * SReg)408 void 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
Profile(llvm::FoldingSetNodeID & ID) const417 void CXXBaseObjectRegion::Profile(llvm::FoldingSetNodeID &ID) const {
418 ProfileRegion(ID, getDecl(), isVirtual(), superRegion);
419 }
420
421 //===----------------------------------------------------------------------===//
422 // Region anchors.
423 //===----------------------------------------------------------------------===//
424
anchor()425 void GlobalsSpaceRegion::anchor() { }
anchor()426 void HeapSpaceRegion::anchor() { }
anchor()427 void UnknownSpaceRegion::anchor() { }
anchor()428 void StackLocalsSpaceRegion::anchor() { }
anchor()429 void StackArgumentsSpaceRegion::anchor() { }
anchor()430 void TypedRegion::anchor() { }
anchor()431 void TypedValueRegion::anchor() { }
anchor()432 void CodeTextRegion::anchor() { }
anchor()433 void SubRegion::anchor() { }
434
435 //===----------------------------------------------------------------------===//
436 // Region pretty-printing.
437 //===----------------------------------------------------------------------===//
438
dump() const439 void MemRegion::dump() const {
440 dumpToStream(llvm::errs());
441 }
442
getString() const443 std::string MemRegion::getString() const {
444 std::string s;
445 llvm::raw_string_ostream os(s);
446 dumpToStream(os);
447 return os.str();
448 }
449
dumpToStream(raw_ostream & os) const450 void MemRegion::dumpToStream(raw_ostream &os) const {
451 os << "<Unknown Region>";
452 }
453
dumpToStream(raw_ostream & os) const454 void AllocaRegion::dumpToStream(raw_ostream &os) const {
455 os << "alloca{" << (const void*) Ex << ',' << Cnt << '}';
456 }
457
dumpToStream(raw_ostream & os) const458 void FunctionTextRegion::dumpToStream(raw_ostream &os) const {
459 os << "code{" << getDecl()->getDeclName().getAsString() << '}';
460 }
461
dumpToStream(raw_ostream & os) const462 void BlockTextRegion::dumpToStream(raw_ostream &os) const {
463 os << "block_code{" << (const void*) this << '}';
464 }
465
dumpToStream(raw_ostream & os) const466 void BlockDataRegion::dumpToStream(raw_ostream &os) const {
467 os << "block_data{" << BC << '}';
468 }
469
dumpToStream(raw_ostream & os) const470 void CompoundLiteralRegion::dumpToStream(raw_ostream &os) const {
471 // FIXME: More elaborate pretty-printing.
472 os << "{ " << (const void*) CL << " }";
473 }
474
dumpToStream(raw_ostream & os) const475 void CXXTempObjectRegion::dumpToStream(raw_ostream &os) const {
476 os << "temp_object{" << getValueType().getAsString() << ','
477 << (const void*) Ex << '}';
478 }
479
dumpToStream(raw_ostream & os) const480 void CXXBaseObjectRegion::dumpToStream(raw_ostream &os) const {
481 os << "base{" << superRegion << ',' << getDecl()->getName() << '}';
482 }
483
dumpToStream(raw_ostream & os) const484 void CXXThisRegion::dumpToStream(raw_ostream &os) const {
485 os << "this";
486 }
487
dumpToStream(raw_ostream & os) const488 void ElementRegion::dumpToStream(raw_ostream &os) const {
489 os << "element{" << superRegion << ','
490 << Index << ',' << getElementType().getAsString() << '}';
491 }
492
dumpToStream(raw_ostream & os) const493 void FieldRegion::dumpToStream(raw_ostream &os) const {
494 os << superRegion << "->" << *getDecl();
495 }
496
dumpToStream(raw_ostream & os) const497 void ObjCIvarRegion::dumpToStream(raw_ostream &os) const {
498 os << "ivar{" << superRegion << ',' << *getDecl() << '}';
499 }
500
dumpToStream(raw_ostream & os) const501 void StringRegion::dumpToStream(raw_ostream &os) const {
502 Str->printPretty(os, 0, PrintingPolicy(getContext().getLangOpts()));
503 }
504
dumpToStream(raw_ostream & os) const505 void ObjCStringRegion::dumpToStream(raw_ostream &os) const {
506 Str->printPretty(os, 0, PrintingPolicy(getContext().getLangOpts()));
507 }
508
dumpToStream(raw_ostream & os) const509 void SymbolicRegion::dumpToStream(raw_ostream &os) const {
510 os << "SymRegion{" << sym << '}';
511 }
512
dumpToStream(raw_ostream & os) const513 void VarRegion::dumpToStream(raw_ostream &os) const {
514 os << *cast<VarDecl>(D);
515 }
516
dump() const517 void RegionRawOffset::dump() const {
518 dumpToStream(llvm::errs());
519 }
520
dumpToStream(raw_ostream & os) const521 void RegionRawOffset::dumpToStream(raw_ostream &os) const {
522 os << "raw_offset{" << getRegion() << ',' << getOffset().getQuantity() << '}';
523 }
524
dumpToStream(raw_ostream & os) const525 void StaticGlobalSpaceRegion::dumpToStream(raw_ostream &os) const {
526 os << "StaticGlobalsMemSpace{" << CR << '}';
527 }
528
dumpToStream(raw_ostream & os) const529 void GlobalInternalSpaceRegion::dumpToStream(raw_ostream &os) const {
530 os << "GlobalInternalSpaceRegion";
531 }
532
dumpToStream(raw_ostream & os) const533 void GlobalSystemSpaceRegion::dumpToStream(raw_ostream &os) const {
534 os << "GlobalSystemSpaceRegion";
535 }
536
dumpToStream(raw_ostream & os) const537 void GlobalImmutableSpaceRegion::dumpToStream(raw_ostream &os) const {
538 os << "GlobalImmutableSpaceRegion";
539 }
540
dumpToStream(raw_ostream & os) const541 void HeapSpaceRegion::dumpToStream(raw_ostream &os) const {
542 os << "HeapSpaceRegion";
543 }
544
dumpToStream(raw_ostream & os) const545 void UnknownSpaceRegion::dumpToStream(raw_ostream &os) const {
546 os << "UnknownSpaceRegion";
547 }
548
dumpToStream(raw_ostream & os) const549 void StackArgumentsSpaceRegion::dumpToStream(raw_ostream &os) const {
550 os << "StackArgumentsSpaceRegion";
551 }
552
dumpToStream(raw_ostream & os) const553 void StackLocalsSpaceRegion::dumpToStream(raw_ostream &os) const {
554 os << "StackLocalsSpaceRegion";
555 }
556
canPrintPretty() const557 bool MemRegion::canPrintPretty() const {
558 return canPrintPrettyAsExpr();
559 }
560
canPrintPrettyAsExpr() const561 bool MemRegion::canPrintPrettyAsExpr() const {
562 return false;
563 }
564
printPretty(raw_ostream & os) const565 void MemRegion::printPretty(raw_ostream &os) const {
566 assert(canPrintPretty() && "This region cannot be printed pretty.");
567 os << "'";
568 printPrettyAsExpr(os);
569 os << "'";
570 return;
571 }
572
printPrettyAsExpr(raw_ostream & os) const573 void MemRegion::printPrettyAsExpr(raw_ostream &os) const {
574 llvm_unreachable("This region cannot be printed pretty.");
575 return;
576 }
577
canPrintPrettyAsExpr() const578 bool VarRegion::canPrintPrettyAsExpr() const {
579 return true;
580 }
581
printPrettyAsExpr(raw_ostream & os) const582 void VarRegion::printPrettyAsExpr(raw_ostream &os) const {
583 os << getDecl()->getName();
584 }
585
canPrintPrettyAsExpr() const586 bool ObjCIvarRegion::canPrintPrettyAsExpr() const {
587 return true;
588 }
589
printPrettyAsExpr(raw_ostream & os) const590 void ObjCIvarRegion::printPrettyAsExpr(raw_ostream &os) const {
591 os << getDecl()->getName();
592 }
593
canPrintPretty() const594 bool FieldRegion::canPrintPretty() const {
595 return true;
596 }
597
canPrintPrettyAsExpr() const598 bool FieldRegion::canPrintPrettyAsExpr() const {
599 return superRegion->canPrintPrettyAsExpr();
600 }
601
printPrettyAsExpr(raw_ostream & os) const602 void FieldRegion::printPrettyAsExpr(raw_ostream &os) const {
603 assert(canPrintPrettyAsExpr());
604 superRegion->printPrettyAsExpr(os);
605 os << "." << getDecl()->getName();
606 }
607
printPretty(raw_ostream & os) const608 void FieldRegion::printPretty(raw_ostream &os) const {
609 if (canPrintPrettyAsExpr()) {
610 os << "\'";
611 printPrettyAsExpr(os);
612 os << "'";
613 } else {
614 os << "field " << "\'" << getDecl()->getName() << "'";
615 }
616 return;
617 }
618
canPrintPrettyAsExpr() const619 bool CXXBaseObjectRegion::canPrintPrettyAsExpr() const {
620 return superRegion->canPrintPrettyAsExpr();
621 }
622
printPrettyAsExpr(raw_ostream & os) const623 void CXXBaseObjectRegion::printPrettyAsExpr(raw_ostream &os) const {
624 superRegion->printPrettyAsExpr(os);
625 }
626
627 //===----------------------------------------------------------------------===//
628 // MemRegionManager methods.
629 //===----------------------------------------------------------------------===//
630
631 template <typename REG>
LazyAllocate(REG * & region)632 const REG *MemRegionManager::LazyAllocate(REG*& region) {
633 if (!region) {
634 region = (REG*) A.Allocate<REG>();
635 new (region) REG(this);
636 }
637
638 return region;
639 }
640
641 template <typename REG, typename ARG>
LazyAllocate(REG * & region,ARG a)642 const REG *MemRegionManager::LazyAllocate(REG*& region, ARG a) {
643 if (!region) {
644 region = (REG*) A.Allocate<REG>();
645 new (region) REG(this, a);
646 }
647
648 return region;
649 }
650
651 const StackLocalsSpaceRegion*
getStackLocalsRegion(const StackFrameContext * STC)652 MemRegionManager::getStackLocalsRegion(const StackFrameContext *STC) {
653 assert(STC);
654 StackLocalsSpaceRegion *&R = StackLocalsSpaceRegions[STC];
655
656 if (R)
657 return R;
658
659 R = A.Allocate<StackLocalsSpaceRegion>();
660 new (R) StackLocalsSpaceRegion(this, STC);
661 return R;
662 }
663
664 const StackArgumentsSpaceRegion *
getStackArgumentsRegion(const StackFrameContext * STC)665 MemRegionManager::getStackArgumentsRegion(const StackFrameContext *STC) {
666 assert(STC);
667 StackArgumentsSpaceRegion *&R = StackArgumentsSpaceRegions[STC];
668
669 if (R)
670 return R;
671
672 R = A.Allocate<StackArgumentsSpaceRegion>();
673 new (R) StackArgumentsSpaceRegion(this, STC);
674 return R;
675 }
676
677 const GlobalsSpaceRegion
getGlobalsRegion(MemRegion::Kind K,const CodeTextRegion * CR)678 *MemRegionManager::getGlobalsRegion(MemRegion::Kind K,
679 const CodeTextRegion *CR) {
680 if (!CR) {
681 if (K == MemRegion::GlobalSystemSpaceRegionKind)
682 return LazyAllocate(SystemGlobals);
683 if (K == MemRegion::GlobalImmutableSpaceRegionKind)
684 return LazyAllocate(ImmutableGlobals);
685 assert(K == MemRegion::GlobalInternalSpaceRegionKind);
686 return LazyAllocate(InternalGlobals);
687 }
688
689 assert(K == MemRegion::StaticGlobalSpaceRegionKind);
690 StaticGlobalSpaceRegion *&R = StaticsGlobalSpaceRegions[CR];
691 if (R)
692 return R;
693
694 R = A.Allocate<StaticGlobalSpaceRegion>();
695 new (R) StaticGlobalSpaceRegion(this, CR);
696 return R;
697 }
698
getHeapRegion()699 const HeapSpaceRegion *MemRegionManager::getHeapRegion() {
700 return LazyAllocate(heap);
701 }
702
getUnknownRegion()703 const MemSpaceRegion *MemRegionManager::getUnknownRegion() {
704 return LazyAllocate(unknown);
705 }
706
getCodeRegion()707 const MemSpaceRegion *MemRegionManager::getCodeRegion() {
708 return LazyAllocate(code);
709 }
710
711 //===----------------------------------------------------------------------===//
712 // Constructing regions.
713 //===----------------------------------------------------------------------===//
getStringRegion(const StringLiteral * Str)714 const StringRegion* MemRegionManager::getStringRegion(const StringLiteral* Str){
715 return getSubRegion<StringRegion>(Str, getGlobalsRegion());
716 }
717
718 const ObjCStringRegion *
getObjCStringRegion(const ObjCStringLiteral * Str)719 MemRegionManager::getObjCStringRegion(const ObjCStringLiteral* Str){
720 return getSubRegion<ObjCStringRegion>(Str, getGlobalsRegion());
721 }
722
723 /// Look through a chain of LocationContexts to either find the
724 /// StackFrameContext that matches a DeclContext, or find a VarRegion
725 /// for a variable captured by a block.
726 static llvm::PointerUnion<const StackFrameContext *, const VarRegion *>
getStackOrCaptureRegionForDeclContext(const LocationContext * LC,const DeclContext * DC,const VarDecl * VD)727 getStackOrCaptureRegionForDeclContext(const LocationContext *LC,
728 const DeclContext *DC,
729 const VarDecl *VD) {
730 while (LC) {
731 if (const StackFrameContext *SFC = dyn_cast<StackFrameContext>(LC)) {
732 if (cast<DeclContext>(SFC->getDecl()) == DC)
733 return SFC;
734 }
735 if (const BlockInvocationContext *BC =
736 dyn_cast<BlockInvocationContext>(LC)) {
737 const BlockDataRegion *BR =
738 static_cast<const BlockDataRegion*>(BC->getContextData());
739 // FIXME: This can be made more efficient.
740 for (BlockDataRegion::referenced_vars_iterator
741 I = BR->referenced_vars_begin(),
742 E = BR->referenced_vars_end(); I != E; ++I) {
743 if (const VarRegion *VR = dyn_cast<VarRegion>(I.getOriginalRegion()))
744 if (VR->getDecl() == VD)
745 return cast<VarRegion>(I.getCapturedRegion());
746 }
747 }
748
749 LC = LC->getParent();
750 }
751 return (const StackFrameContext*)0;
752 }
753
getVarRegion(const VarDecl * D,const LocationContext * LC)754 const VarRegion* MemRegionManager::getVarRegion(const VarDecl *D,
755 const LocationContext *LC) {
756 const MemRegion *sReg = 0;
757
758 if (D->hasGlobalStorage() && !D->isStaticLocal()) {
759
760 // First handle the globals defined in system headers.
761 if (C.getSourceManager().isInSystemHeader(D->getLocation())) {
762 // Whitelist the system globals which often DO GET modified, assume the
763 // rest are immutable.
764 if (D->getName().find("errno") != StringRef::npos)
765 sReg = getGlobalsRegion(MemRegion::GlobalSystemSpaceRegionKind);
766 else
767 sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
768
769 // Treat other globals as GlobalInternal unless they are constants.
770 } else {
771 QualType GQT = D->getType();
772 const Type *GT = GQT.getTypePtrOrNull();
773 // TODO: We could walk the complex types here and see if everything is
774 // constified.
775 if (GT && GQT.isConstQualified() && GT->isArithmeticType())
776 sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
777 else
778 sReg = getGlobalsRegion();
779 }
780
781 // Finally handle static locals.
782 } else {
783 // FIXME: Once we implement scope handling, we will need to properly lookup
784 // 'D' to the proper LocationContext.
785 const DeclContext *DC = D->getDeclContext();
786 llvm::PointerUnion<const StackFrameContext *, const VarRegion *> V =
787 getStackOrCaptureRegionForDeclContext(LC, DC, D);
788
789 if (V.is<const VarRegion*>())
790 return V.get<const VarRegion*>();
791
792 const StackFrameContext *STC = V.get<const StackFrameContext*>();
793
794 if (!STC)
795 sReg = getUnknownRegion();
796 else {
797 if (D->hasLocalStorage()) {
798 sReg = isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)
799 ? static_cast<const MemRegion*>(getStackArgumentsRegion(STC))
800 : static_cast<const MemRegion*>(getStackLocalsRegion(STC));
801 }
802 else {
803 assert(D->isStaticLocal());
804 const Decl *STCD = STC->getDecl();
805 if (isa<FunctionDecl>(STCD) || isa<ObjCMethodDecl>(STCD))
806 sReg = getGlobalsRegion(MemRegion::StaticGlobalSpaceRegionKind,
807 getFunctionTextRegion(cast<NamedDecl>(STCD)));
808 else if (const BlockDecl *BD = dyn_cast<BlockDecl>(STCD)) {
809 // FIXME: The fallback type here is totally bogus -- though it should
810 // never be queried, it will prevent uniquing with the real
811 // BlockTextRegion. Ideally we'd fix the AST so that we always had a
812 // signature.
813 QualType T;
814 if (const TypeSourceInfo *TSI = BD->getSignatureAsWritten())
815 T = TSI->getType();
816 else
817 T = getContext().getFunctionNoProtoType(getContext().VoidTy);
818
819 const BlockTextRegion *BTR =
820 getBlockTextRegion(BD, C.getCanonicalType(T),
821 STC->getAnalysisDeclContext());
822 sReg = getGlobalsRegion(MemRegion::StaticGlobalSpaceRegionKind,
823 BTR);
824 }
825 else {
826 sReg = getGlobalsRegion();
827 }
828 }
829 }
830 }
831
832 return getSubRegion<VarRegion>(D, sReg);
833 }
834
getVarRegion(const VarDecl * D,const MemRegion * superR)835 const VarRegion *MemRegionManager::getVarRegion(const VarDecl *D,
836 const MemRegion *superR) {
837 return getSubRegion<VarRegion>(D, superR);
838 }
839
840 const BlockDataRegion *
getBlockDataRegion(const BlockTextRegion * BC,const LocationContext * LC)841 MemRegionManager::getBlockDataRegion(const BlockTextRegion *BC,
842 const LocationContext *LC) {
843 const MemRegion *sReg = 0;
844 const BlockDecl *BD = BC->getDecl();
845 if (!BD->hasCaptures()) {
846 // This handles 'static' blocks.
847 sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
848 }
849 else {
850 if (LC) {
851 // FIXME: Once we implement scope handling, we want the parent region
852 // to be the scope.
853 const StackFrameContext *STC = LC->getCurrentStackFrame();
854 assert(STC);
855 sReg = getStackLocalsRegion(STC);
856 }
857 else {
858 // We allow 'LC' to be NULL for cases where want BlockDataRegions
859 // without context-sensitivity.
860 sReg = getUnknownRegion();
861 }
862 }
863
864 return getSubRegion<BlockDataRegion>(BC, LC, sReg);
865 }
866
867 const CXXTempObjectRegion *
getCXXStaticTempObjectRegion(const Expr * Ex)868 MemRegionManager::getCXXStaticTempObjectRegion(const Expr *Ex) {
869 return getSubRegion<CXXTempObjectRegion>(
870 Ex, getGlobalsRegion(MemRegion::GlobalInternalSpaceRegionKind, NULL));
871 }
872
873 const CompoundLiteralRegion*
getCompoundLiteralRegion(const CompoundLiteralExpr * CL,const LocationContext * LC)874 MemRegionManager::getCompoundLiteralRegion(const CompoundLiteralExpr *CL,
875 const LocationContext *LC) {
876
877 const MemRegion *sReg = 0;
878
879 if (CL->isFileScope())
880 sReg = getGlobalsRegion();
881 else {
882 const StackFrameContext *STC = LC->getCurrentStackFrame();
883 assert(STC);
884 sReg = getStackLocalsRegion(STC);
885 }
886
887 return getSubRegion<CompoundLiteralRegion>(CL, sReg);
888 }
889
890 const ElementRegion*
getElementRegion(QualType elementType,NonLoc Idx,const MemRegion * superRegion,ASTContext & Ctx)891 MemRegionManager::getElementRegion(QualType elementType, NonLoc Idx,
892 const MemRegion* superRegion,
893 ASTContext &Ctx){
894
895 QualType T = Ctx.getCanonicalType(elementType).getUnqualifiedType();
896
897 llvm::FoldingSetNodeID ID;
898 ElementRegion::ProfileRegion(ID, T, Idx, superRegion);
899
900 void *InsertPos;
901 MemRegion* data = Regions.FindNodeOrInsertPos(ID, InsertPos);
902 ElementRegion* R = cast_or_null<ElementRegion>(data);
903
904 if (!R) {
905 R = (ElementRegion*) A.Allocate<ElementRegion>();
906 new (R) ElementRegion(T, Idx, superRegion);
907 Regions.InsertNode(R, InsertPos);
908 }
909
910 return R;
911 }
912
913 const FunctionTextRegion *
getFunctionTextRegion(const NamedDecl * FD)914 MemRegionManager::getFunctionTextRegion(const NamedDecl *FD) {
915 return getSubRegion<FunctionTextRegion>(FD, getCodeRegion());
916 }
917
918 const BlockTextRegion *
getBlockTextRegion(const BlockDecl * BD,CanQualType locTy,AnalysisDeclContext * AC)919 MemRegionManager::getBlockTextRegion(const BlockDecl *BD, CanQualType locTy,
920 AnalysisDeclContext *AC) {
921 return getSubRegion<BlockTextRegion>(BD, locTy, AC, getCodeRegion());
922 }
923
924
925 /// getSymbolicRegion - Retrieve or create a "symbolic" memory region.
getSymbolicRegion(SymbolRef sym)926 const SymbolicRegion *MemRegionManager::getSymbolicRegion(SymbolRef sym) {
927 return getSubRegion<SymbolicRegion>(sym, getUnknownRegion());
928 }
929
getSymbolicHeapRegion(SymbolRef Sym)930 const SymbolicRegion *MemRegionManager::getSymbolicHeapRegion(SymbolRef Sym) {
931 return getSubRegion<SymbolicRegion>(Sym, getHeapRegion());
932 }
933
934 const FieldRegion*
getFieldRegion(const FieldDecl * d,const MemRegion * superRegion)935 MemRegionManager::getFieldRegion(const FieldDecl *d,
936 const MemRegion* superRegion){
937 return getSubRegion<FieldRegion>(d, superRegion);
938 }
939
940 const ObjCIvarRegion*
getObjCIvarRegion(const ObjCIvarDecl * d,const MemRegion * superRegion)941 MemRegionManager::getObjCIvarRegion(const ObjCIvarDecl *d,
942 const MemRegion* superRegion) {
943 return getSubRegion<ObjCIvarRegion>(d, superRegion);
944 }
945
946 const CXXTempObjectRegion*
getCXXTempObjectRegion(Expr const * E,LocationContext const * LC)947 MemRegionManager::getCXXTempObjectRegion(Expr const *E,
948 LocationContext const *LC) {
949 const StackFrameContext *SFC = LC->getCurrentStackFrame();
950 assert(SFC);
951 return getSubRegion<CXXTempObjectRegion>(E, getStackLocalsRegion(SFC));
952 }
953
954 /// Checks whether \p BaseClass is a valid virtual or direct non-virtual base
955 /// class of the type of \p Super.
isValidBaseClass(const CXXRecordDecl * BaseClass,const TypedValueRegion * Super,bool IsVirtual)956 static bool isValidBaseClass(const CXXRecordDecl *BaseClass,
957 const TypedValueRegion *Super,
958 bool IsVirtual) {
959 BaseClass = BaseClass->getCanonicalDecl();
960
961 const CXXRecordDecl *Class = Super->getValueType()->getAsCXXRecordDecl();
962 if (!Class)
963 return true;
964
965 if (IsVirtual)
966 return Class->isVirtuallyDerivedFrom(BaseClass);
967
968 for (CXXRecordDecl::base_class_const_iterator I = Class->bases_begin(),
969 E = Class->bases_end();
970 I != E; ++I) {
971 if (I->getType()->getAsCXXRecordDecl()->getCanonicalDecl() == BaseClass)
972 return true;
973 }
974
975 return false;
976 }
977
978 const CXXBaseObjectRegion *
getCXXBaseObjectRegion(const CXXRecordDecl * RD,const MemRegion * Super,bool IsVirtual)979 MemRegionManager::getCXXBaseObjectRegion(const CXXRecordDecl *RD,
980 const MemRegion *Super,
981 bool IsVirtual) {
982 if (isa<TypedValueRegion>(Super)) {
983 assert(isValidBaseClass(RD, dyn_cast<TypedValueRegion>(Super), IsVirtual));
984 (void)&isValidBaseClass;
985
986 if (IsVirtual) {
987 // Virtual base regions should not be layered, since the layout rules
988 // are different.
989 while (const CXXBaseObjectRegion *Base =
990 dyn_cast<CXXBaseObjectRegion>(Super)) {
991 Super = Base->getSuperRegion();
992 }
993 assert(Super && !isa<MemSpaceRegion>(Super));
994 }
995 }
996
997 return getSubRegion<CXXBaseObjectRegion>(RD, IsVirtual, Super);
998 }
999
1000 const CXXThisRegion*
getCXXThisRegion(QualType thisPointerTy,const LocationContext * LC)1001 MemRegionManager::getCXXThisRegion(QualType thisPointerTy,
1002 const LocationContext *LC) {
1003 const StackFrameContext *STC = LC->getCurrentStackFrame();
1004 assert(STC);
1005 const PointerType *PT = thisPointerTy->getAs<PointerType>();
1006 assert(PT);
1007 return getSubRegion<CXXThisRegion>(PT, getStackArgumentsRegion(STC));
1008 }
1009
1010 const AllocaRegion*
getAllocaRegion(const Expr * E,unsigned cnt,const LocationContext * LC)1011 MemRegionManager::getAllocaRegion(const Expr *E, unsigned cnt,
1012 const LocationContext *LC) {
1013 const StackFrameContext *STC = LC->getCurrentStackFrame();
1014 assert(STC);
1015 return getSubRegion<AllocaRegion>(E, cnt, getStackLocalsRegion(STC));
1016 }
1017
getMemorySpace() const1018 const MemSpaceRegion *MemRegion::getMemorySpace() const {
1019 const MemRegion *R = this;
1020 const SubRegion* SR = dyn_cast<SubRegion>(this);
1021
1022 while (SR) {
1023 R = SR->getSuperRegion();
1024 SR = dyn_cast<SubRegion>(R);
1025 }
1026
1027 return dyn_cast<MemSpaceRegion>(R);
1028 }
1029
hasStackStorage() const1030 bool MemRegion::hasStackStorage() const {
1031 return isa<StackSpaceRegion>(getMemorySpace());
1032 }
1033
hasStackNonParametersStorage() const1034 bool MemRegion::hasStackNonParametersStorage() const {
1035 return isa<StackLocalsSpaceRegion>(getMemorySpace());
1036 }
1037
hasStackParametersStorage() const1038 bool MemRegion::hasStackParametersStorage() const {
1039 return isa<StackArgumentsSpaceRegion>(getMemorySpace());
1040 }
1041
hasGlobalsOrParametersStorage() const1042 bool MemRegion::hasGlobalsOrParametersStorage() const {
1043 const MemSpaceRegion *MS = getMemorySpace();
1044 return isa<StackArgumentsSpaceRegion>(MS) ||
1045 isa<GlobalsSpaceRegion>(MS);
1046 }
1047
1048 // getBaseRegion strips away all elements and fields, and get the base region
1049 // of them.
getBaseRegion() const1050 const MemRegion *MemRegion::getBaseRegion() const {
1051 const MemRegion *R = this;
1052 while (true) {
1053 switch (R->getKind()) {
1054 case MemRegion::ElementRegionKind:
1055 case MemRegion::FieldRegionKind:
1056 case MemRegion::ObjCIvarRegionKind:
1057 case MemRegion::CXXBaseObjectRegionKind:
1058 R = cast<SubRegion>(R)->getSuperRegion();
1059 continue;
1060 default:
1061 break;
1062 }
1063 break;
1064 }
1065 return R;
1066 }
1067
isSubRegionOf(const MemRegion * R) const1068 bool MemRegion::isSubRegionOf(const MemRegion *R) const {
1069 return false;
1070 }
1071
1072 //===----------------------------------------------------------------------===//
1073 // View handling.
1074 //===----------------------------------------------------------------------===//
1075
StripCasts(bool StripBaseCasts) const1076 const MemRegion *MemRegion::StripCasts(bool StripBaseCasts) const {
1077 const MemRegion *R = this;
1078 while (true) {
1079 switch (R->getKind()) {
1080 case ElementRegionKind: {
1081 const ElementRegion *ER = cast<ElementRegion>(R);
1082 if (!ER->getIndex().isZeroConstant())
1083 return R;
1084 R = ER->getSuperRegion();
1085 break;
1086 }
1087 case CXXBaseObjectRegionKind:
1088 if (!StripBaseCasts)
1089 return R;
1090 R = cast<CXXBaseObjectRegion>(R)->getSuperRegion();
1091 break;
1092 default:
1093 return R;
1094 }
1095 }
1096 }
1097
getSymbolicBase() const1098 const SymbolicRegion *MemRegion::getSymbolicBase() const {
1099 const SubRegion *SubR = dyn_cast<SubRegion>(this);
1100
1101 while (SubR) {
1102 if (const SymbolicRegion *SymR = dyn_cast<SymbolicRegion>(SubR))
1103 return SymR;
1104 SubR = dyn_cast<SubRegion>(SubR->getSuperRegion());
1105 }
1106 return 0;
1107 }
1108
1109 // FIXME: Merge with the implementation of the same method in Store.cpp
IsCompleteType(ASTContext & Ctx,QualType Ty)1110 static bool IsCompleteType(ASTContext &Ctx, QualType Ty) {
1111 if (const RecordType *RT = Ty->getAs<RecordType>()) {
1112 const RecordDecl *D = RT->getDecl();
1113 if (!D->getDefinition())
1114 return false;
1115 }
1116
1117 return true;
1118 }
1119
getAsArrayOffset() const1120 RegionRawOffset ElementRegion::getAsArrayOffset() const {
1121 CharUnits offset = CharUnits::Zero();
1122 const ElementRegion *ER = this;
1123 const MemRegion *superR = NULL;
1124 ASTContext &C = getContext();
1125
1126 // FIXME: Handle multi-dimensional arrays.
1127
1128 while (ER) {
1129 superR = ER->getSuperRegion();
1130
1131 // FIXME: generalize to symbolic offsets.
1132 SVal index = ER->getIndex();
1133 if (Optional<nonloc::ConcreteInt> CI = index.getAs<nonloc::ConcreteInt>()) {
1134 // Update the offset.
1135 int64_t i = CI->getValue().getSExtValue();
1136
1137 if (i != 0) {
1138 QualType elemType = ER->getElementType();
1139
1140 // If we are pointing to an incomplete type, go no further.
1141 if (!IsCompleteType(C, elemType)) {
1142 superR = ER;
1143 break;
1144 }
1145
1146 CharUnits size = C.getTypeSizeInChars(elemType);
1147 offset += (i * size);
1148 }
1149
1150 // Go to the next ElementRegion (if any).
1151 ER = dyn_cast<ElementRegion>(superR);
1152 continue;
1153 }
1154
1155 return NULL;
1156 }
1157
1158 assert(superR && "super region cannot be NULL");
1159 return RegionRawOffset(superR, offset);
1160 }
1161
1162
1163 /// Returns true if \p Base is an immediate base class of \p Child
isImmediateBase(const CXXRecordDecl * Child,const CXXRecordDecl * Base)1164 static bool isImmediateBase(const CXXRecordDecl *Child,
1165 const CXXRecordDecl *Base) {
1166 // Note that we do NOT canonicalize the base class here, because
1167 // ASTRecordLayout doesn't either. If that leads us down the wrong path,
1168 // so be it; at least we won't crash.
1169 for (CXXRecordDecl::base_class_const_iterator I = Child->bases_begin(),
1170 E = Child->bases_end();
1171 I != E; ++I) {
1172 if (I->getType()->getAsCXXRecordDecl() == Base)
1173 return true;
1174 }
1175
1176 return false;
1177 }
1178
getAsOffset() const1179 RegionOffset MemRegion::getAsOffset() const {
1180 const MemRegion *R = this;
1181 const MemRegion *SymbolicOffsetBase = 0;
1182 int64_t Offset = 0;
1183
1184 while (1) {
1185 switch (R->getKind()) {
1186 case GenericMemSpaceRegionKind:
1187 case StackLocalsSpaceRegionKind:
1188 case StackArgumentsSpaceRegionKind:
1189 case HeapSpaceRegionKind:
1190 case UnknownSpaceRegionKind:
1191 case StaticGlobalSpaceRegionKind:
1192 case GlobalInternalSpaceRegionKind:
1193 case GlobalSystemSpaceRegionKind:
1194 case GlobalImmutableSpaceRegionKind:
1195 // Stores can bind directly to a region space to set a default value.
1196 assert(Offset == 0 && !SymbolicOffsetBase);
1197 goto Finish;
1198
1199 case FunctionTextRegionKind:
1200 case BlockTextRegionKind:
1201 case BlockDataRegionKind:
1202 // These will never have bindings, but may end up having values requested
1203 // if the user does some strange casting.
1204 if (Offset != 0)
1205 SymbolicOffsetBase = R;
1206 goto Finish;
1207
1208 case SymbolicRegionKind:
1209 case AllocaRegionKind:
1210 case CompoundLiteralRegionKind:
1211 case CXXThisRegionKind:
1212 case StringRegionKind:
1213 case ObjCStringRegionKind:
1214 case VarRegionKind:
1215 case CXXTempObjectRegionKind:
1216 // Usual base regions.
1217 goto Finish;
1218
1219 case ObjCIvarRegionKind:
1220 // This is a little strange, but it's a compromise between
1221 // ObjCIvarRegions having unknown compile-time offsets (when using the
1222 // non-fragile runtime) and yet still being distinct, non-overlapping
1223 // regions. Thus we treat them as "like" base regions for the purposes
1224 // of computing offsets.
1225 goto Finish;
1226
1227 case CXXBaseObjectRegionKind: {
1228 const CXXBaseObjectRegion *BOR = cast<CXXBaseObjectRegion>(R);
1229 R = BOR->getSuperRegion();
1230
1231 QualType Ty;
1232 bool RootIsSymbolic = false;
1233 if (const TypedValueRegion *TVR = dyn_cast<TypedValueRegion>(R)) {
1234 Ty = TVR->getDesugaredValueType(getContext());
1235 } else if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) {
1236 // If our base region is symbolic, we don't know what type it really is.
1237 // Pretend the type of the symbol is the true dynamic type.
1238 // (This will at least be self-consistent for the life of the symbol.)
1239 Ty = SR->getSymbol()->getType()->getPointeeType();
1240 RootIsSymbolic = true;
1241 }
1242
1243 const CXXRecordDecl *Child = Ty->getAsCXXRecordDecl();
1244 if (!Child) {
1245 // We cannot compute the offset of the base class.
1246 SymbolicOffsetBase = R;
1247 }
1248
1249 if (RootIsSymbolic) {
1250 // Base layers on symbolic regions may not be type-correct.
1251 // Double-check the inheritance here, and revert to a symbolic offset
1252 // if it's invalid (e.g. due to a reinterpret_cast).
1253 if (BOR->isVirtual()) {
1254 if (!Child->isVirtuallyDerivedFrom(BOR->getDecl()))
1255 SymbolicOffsetBase = R;
1256 } else {
1257 if (!isImmediateBase(Child, BOR->getDecl()))
1258 SymbolicOffsetBase = R;
1259 }
1260 }
1261
1262 // Don't bother calculating precise offsets if we already have a
1263 // symbolic offset somewhere in the chain.
1264 if (SymbolicOffsetBase)
1265 continue;
1266
1267 CharUnits BaseOffset;
1268 const ASTRecordLayout &Layout = getContext().getASTRecordLayout(Child);
1269 if (BOR->isVirtual())
1270 BaseOffset = Layout.getVBaseClassOffset(BOR->getDecl());
1271 else
1272 BaseOffset = Layout.getBaseClassOffset(BOR->getDecl());
1273
1274 // The base offset is in chars, not in bits.
1275 Offset += BaseOffset.getQuantity() * getContext().getCharWidth();
1276 break;
1277 }
1278 case ElementRegionKind: {
1279 const ElementRegion *ER = cast<ElementRegion>(R);
1280 R = ER->getSuperRegion();
1281
1282 QualType EleTy = ER->getValueType();
1283 if (!IsCompleteType(getContext(), EleTy)) {
1284 // We cannot compute the offset of the base class.
1285 SymbolicOffsetBase = R;
1286 continue;
1287 }
1288
1289 SVal Index = ER->getIndex();
1290 if (Optional<nonloc::ConcreteInt> CI =
1291 Index.getAs<nonloc::ConcreteInt>()) {
1292 // Don't bother calculating precise offsets if we already have a
1293 // symbolic offset somewhere in the chain.
1294 if (SymbolicOffsetBase)
1295 continue;
1296
1297 int64_t i = CI->getValue().getSExtValue();
1298 // This type size is in bits.
1299 Offset += i * getContext().getTypeSize(EleTy);
1300 } else {
1301 // We cannot compute offset for non-concrete index.
1302 SymbolicOffsetBase = R;
1303 }
1304 break;
1305 }
1306 case FieldRegionKind: {
1307 const FieldRegion *FR = cast<FieldRegion>(R);
1308 R = FR->getSuperRegion();
1309
1310 const RecordDecl *RD = FR->getDecl()->getParent();
1311 if (RD->isUnion() || !RD->isCompleteDefinition()) {
1312 // We cannot compute offset for incomplete type.
1313 // For unions, we could treat everything as offset 0, but we'd rather
1314 // treat each field as a symbolic offset so they aren't stored on top
1315 // of each other, since we depend on things in typed regions actually
1316 // matching their types.
1317 SymbolicOffsetBase = R;
1318 }
1319
1320 // Don't bother calculating precise offsets if we already have a
1321 // symbolic offset somewhere in the chain.
1322 if (SymbolicOffsetBase)
1323 continue;
1324
1325 // Get the field number.
1326 unsigned idx = 0;
1327 for (RecordDecl::field_iterator FI = RD->field_begin(),
1328 FE = RD->field_end(); FI != FE; ++FI, ++idx)
1329 if (FR->getDecl() == *FI)
1330 break;
1331
1332 const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
1333 // This is offset in bits.
1334 Offset += Layout.getFieldOffset(idx);
1335 break;
1336 }
1337 }
1338 }
1339
1340 Finish:
1341 if (SymbolicOffsetBase)
1342 return RegionOffset(SymbolicOffsetBase, RegionOffset::Symbolic);
1343 return RegionOffset(R, Offset);
1344 }
1345
1346 //===----------------------------------------------------------------------===//
1347 // BlockDataRegion
1348 //===----------------------------------------------------------------------===//
1349
1350 std::pair<const VarRegion *, const VarRegion *>
getCaptureRegions(const VarDecl * VD)1351 BlockDataRegion::getCaptureRegions(const VarDecl *VD) {
1352 MemRegionManager &MemMgr = *getMemRegionManager();
1353 const VarRegion *VR = 0;
1354 const VarRegion *OriginalVR = 0;
1355
1356 if (!VD->getAttr<BlocksAttr>() && VD->hasLocalStorage()) {
1357 VR = MemMgr.getVarRegion(VD, this);
1358 OriginalVR = MemMgr.getVarRegion(VD, LC);
1359 }
1360 else {
1361 if (LC) {
1362 VR = MemMgr.getVarRegion(VD, LC);
1363 OriginalVR = VR;
1364 }
1365 else {
1366 VR = MemMgr.getVarRegion(VD, MemMgr.getUnknownRegion());
1367 OriginalVR = MemMgr.getVarRegion(VD, LC);
1368 }
1369 }
1370 return std::make_pair(VR, OriginalVR);
1371 }
1372
LazyInitializeReferencedVars()1373 void BlockDataRegion::LazyInitializeReferencedVars() {
1374 if (ReferencedVars)
1375 return;
1376
1377 AnalysisDeclContext *AC = getCodeRegion()->getAnalysisDeclContext();
1378 AnalysisDeclContext::referenced_decls_iterator I, E;
1379 llvm::tie(I, E) = AC->getReferencedBlockVars(BC->getDecl());
1380
1381 if (I == E) {
1382 ReferencedVars = (void*) 0x1;
1383 return;
1384 }
1385
1386 MemRegionManager &MemMgr = *getMemRegionManager();
1387 llvm::BumpPtrAllocator &A = MemMgr.getAllocator();
1388 BumpVectorContext BC(A);
1389
1390 typedef BumpVector<const MemRegion*> VarVec;
1391 VarVec *BV = (VarVec*) A.Allocate<VarVec>();
1392 new (BV) VarVec(BC, E - I);
1393 VarVec *BVOriginal = (VarVec*) A.Allocate<VarVec>();
1394 new (BVOriginal) VarVec(BC, E - I);
1395
1396 for ( ; I != E; ++I) {
1397 const VarRegion *VR = 0;
1398 const VarRegion *OriginalVR = 0;
1399 llvm::tie(VR, OriginalVR) = getCaptureRegions(*I);
1400 assert(VR);
1401 assert(OriginalVR);
1402 BV->push_back(VR, BC);
1403 BVOriginal->push_back(OriginalVR, BC);
1404 }
1405
1406 ReferencedVars = BV;
1407 OriginalVars = BVOriginal;
1408 }
1409
1410 BlockDataRegion::referenced_vars_iterator
referenced_vars_begin() const1411 BlockDataRegion::referenced_vars_begin() const {
1412 const_cast<BlockDataRegion*>(this)->LazyInitializeReferencedVars();
1413
1414 BumpVector<const MemRegion*> *Vec =
1415 static_cast<BumpVector<const MemRegion*>*>(ReferencedVars);
1416
1417 if (Vec == (void*) 0x1)
1418 return BlockDataRegion::referenced_vars_iterator(0, 0);
1419
1420 BumpVector<const MemRegion*> *VecOriginal =
1421 static_cast<BumpVector<const MemRegion*>*>(OriginalVars);
1422
1423 return BlockDataRegion::referenced_vars_iterator(Vec->begin(),
1424 VecOriginal->begin());
1425 }
1426
1427 BlockDataRegion::referenced_vars_iterator
referenced_vars_end() const1428 BlockDataRegion::referenced_vars_end() const {
1429 const_cast<BlockDataRegion*>(this)->LazyInitializeReferencedVars();
1430
1431 BumpVector<const MemRegion*> *Vec =
1432 static_cast<BumpVector<const MemRegion*>*>(ReferencedVars);
1433
1434 if (Vec == (void*) 0x1)
1435 return BlockDataRegion::referenced_vars_iterator(0, 0);
1436
1437 BumpVector<const MemRegion*> *VecOriginal =
1438 static_cast<BumpVector<const MemRegion*>*>(OriginalVars);
1439
1440 return BlockDataRegion::referenced_vars_iterator(Vec->end(),
1441 VecOriginal->end());
1442 }
1443
getOriginalRegion(const VarRegion * R) const1444 const VarRegion *BlockDataRegion::getOriginalRegion(const VarRegion *R) const {
1445 for (referenced_vars_iterator I = referenced_vars_begin(),
1446 E = referenced_vars_end();
1447 I != E; ++I) {
1448 if (I.getCapturedRegion() == R)
1449 return I.getOriginalRegion();
1450 }
1451 return 0;
1452 }
1453