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 != nullptr) {
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() : nullptr;
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 assert(Str != nullptr && "Expecting non-null StringLiteral");
512 Str->printPretty(os, nullptr, PrintingPolicy(getContext().getLangOpts()));
513 }
514
dumpToStream(raw_ostream & os) const515 void ObjCStringRegion::dumpToStream(raw_ostream &os) const {
516 assert(Str != nullptr && "Expecting non-null ObjCStringLiteral");
517 Str->printPretty(os, nullptr, PrintingPolicy(getContext().getLangOpts()));
518 }
519
dumpToStream(raw_ostream & os) const520 void SymbolicRegion::dumpToStream(raw_ostream &os) const {
521 os << "SymRegion{" << sym << '}';
522 }
523
dumpToStream(raw_ostream & os) const524 void VarRegion::dumpToStream(raw_ostream &os) const {
525 os << *cast<VarDecl>(D);
526 }
527
dump() const528 void RegionRawOffset::dump() const {
529 dumpToStream(llvm::errs());
530 }
531
dumpToStream(raw_ostream & os) const532 void RegionRawOffset::dumpToStream(raw_ostream &os) const {
533 os << "raw_offset{" << getRegion() << ',' << getOffset().getQuantity() << '}';
534 }
535
dumpToStream(raw_ostream & os) const536 void StaticGlobalSpaceRegion::dumpToStream(raw_ostream &os) const {
537 os << "StaticGlobalsMemSpace{" << CR << '}';
538 }
539
dumpToStream(raw_ostream & os) const540 void GlobalInternalSpaceRegion::dumpToStream(raw_ostream &os) const {
541 os << "GlobalInternalSpaceRegion";
542 }
543
dumpToStream(raw_ostream & os) const544 void GlobalSystemSpaceRegion::dumpToStream(raw_ostream &os) const {
545 os << "GlobalSystemSpaceRegion";
546 }
547
dumpToStream(raw_ostream & os) const548 void GlobalImmutableSpaceRegion::dumpToStream(raw_ostream &os) const {
549 os << "GlobalImmutableSpaceRegion";
550 }
551
dumpToStream(raw_ostream & os) const552 void HeapSpaceRegion::dumpToStream(raw_ostream &os) const {
553 os << "HeapSpaceRegion";
554 }
555
dumpToStream(raw_ostream & os) const556 void UnknownSpaceRegion::dumpToStream(raw_ostream &os) const {
557 os << "UnknownSpaceRegion";
558 }
559
dumpToStream(raw_ostream & os) const560 void StackArgumentsSpaceRegion::dumpToStream(raw_ostream &os) const {
561 os << "StackArgumentsSpaceRegion";
562 }
563
dumpToStream(raw_ostream & os) const564 void StackLocalsSpaceRegion::dumpToStream(raw_ostream &os) const {
565 os << "StackLocalsSpaceRegion";
566 }
567
canPrintPretty() const568 bool MemRegion::canPrintPretty() const {
569 return canPrintPrettyAsExpr();
570 }
571
canPrintPrettyAsExpr() const572 bool MemRegion::canPrintPrettyAsExpr() const {
573 return false;
574 }
575
printPretty(raw_ostream & os) const576 void MemRegion::printPretty(raw_ostream &os) const {
577 assert(canPrintPretty() && "This region cannot be printed pretty.");
578 os << "'";
579 printPrettyAsExpr(os);
580 os << "'";
581 return;
582 }
583
printPrettyAsExpr(raw_ostream & os) const584 void MemRegion::printPrettyAsExpr(raw_ostream &os) const {
585 llvm_unreachable("This region cannot be printed pretty.");
586 return;
587 }
588
canPrintPrettyAsExpr() const589 bool VarRegion::canPrintPrettyAsExpr() const {
590 return true;
591 }
592
printPrettyAsExpr(raw_ostream & os) const593 void VarRegion::printPrettyAsExpr(raw_ostream &os) const {
594 os << getDecl()->getName();
595 }
596
canPrintPrettyAsExpr() const597 bool ObjCIvarRegion::canPrintPrettyAsExpr() const {
598 return true;
599 }
600
printPrettyAsExpr(raw_ostream & os) const601 void ObjCIvarRegion::printPrettyAsExpr(raw_ostream &os) const {
602 os << getDecl()->getName();
603 }
604
canPrintPretty() const605 bool FieldRegion::canPrintPretty() const {
606 return true;
607 }
608
canPrintPrettyAsExpr() const609 bool FieldRegion::canPrintPrettyAsExpr() const {
610 return superRegion->canPrintPrettyAsExpr();
611 }
612
printPrettyAsExpr(raw_ostream & os) const613 void FieldRegion::printPrettyAsExpr(raw_ostream &os) const {
614 assert(canPrintPrettyAsExpr());
615 superRegion->printPrettyAsExpr(os);
616 os << "." << getDecl()->getName();
617 }
618
printPretty(raw_ostream & os) const619 void FieldRegion::printPretty(raw_ostream &os) const {
620 if (canPrintPrettyAsExpr()) {
621 os << "\'";
622 printPrettyAsExpr(os);
623 os << "'";
624 } else {
625 os << "field " << "\'" << getDecl()->getName() << "'";
626 }
627 return;
628 }
629
canPrintPrettyAsExpr() const630 bool CXXBaseObjectRegion::canPrintPrettyAsExpr() const {
631 return superRegion->canPrintPrettyAsExpr();
632 }
633
printPrettyAsExpr(raw_ostream & os) const634 void CXXBaseObjectRegion::printPrettyAsExpr(raw_ostream &os) const {
635 superRegion->printPrettyAsExpr(os);
636 }
637
638 //===----------------------------------------------------------------------===//
639 // MemRegionManager methods.
640 //===----------------------------------------------------------------------===//
641
642 template <typename REG>
LazyAllocate(REG * & region)643 const REG *MemRegionManager::LazyAllocate(REG*& region) {
644 if (!region) {
645 region = (REG*) A.Allocate<REG>();
646 new (region) REG(this);
647 }
648
649 return region;
650 }
651
652 template <typename REG, typename ARG>
LazyAllocate(REG * & region,ARG a)653 const REG *MemRegionManager::LazyAllocate(REG*& region, ARG a) {
654 if (!region) {
655 region = (REG*) A.Allocate<REG>();
656 new (region) REG(this, a);
657 }
658
659 return region;
660 }
661
662 const StackLocalsSpaceRegion*
getStackLocalsRegion(const StackFrameContext * STC)663 MemRegionManager::getStackLocalsRegion(const StackFrameContext *STC) {
664 assert(STC);
665 StackLocalsSpaceRegion *&R = StackLocalsSpaceRegions[STC];
666
667 if (R)
668 return R;
669
670 R = A.Allocate<StackLocalsSpaceRegion>();
671 new (R) StackLocalsSpaceRegion(this, STC);
672 return R;
673 }
674
675 const StackArgumentsSpaceRegion *
getStackArgumentsRegion(const StackFrameContext * STC)676 MemRegionManager::getStackArgumentsRegion(const StackFrameContext *STC) {
677 assert(STC);
678 StackArgumentsSpaceRegion *&R = StackArgumentsSpaceRegions[STC];
679
680 if (R)
681 return R;
682
683 R = A.Allocate<StackArgumentsSpaceRegion>();
684 new (R) StackArgumentsSpaceRegion(this, STC);
685 return R;
686 }
687
688 const GlobalsSpaceRegion
getGlobalsRegion(MemRegion::Kind K,const CodeTextRegion * CR)689 *MemRegionManager::getGlobalsRegion(MemRegion::Kind K,
690 const CodeTextRegion *CR) {
691 if (!CR) {
692 if (K == MemRegion::GlobalSystemSpaceRegionKind)
693 return LazyAllocate(SystemGlobals);
694 if (K == MemRegion::GlobalImmutableSpaceRegionKind)
695 return LazyAllocate(ImmutableGlobals);
696 assert(K == MemRegion::GlobalInternalSpaceRegionKind);
697 return LazyAllocate(InternalGlobals);
698 }
699
700 assert(K == MemRegion::StaticGlobalSpaceRegionKind);
701 StaticGlobalSpaceRegion *&R = StaticsGlobalSpaceRegions[CR];
702 if (R)
703 return R;
704
705 R = A.Allocate<StaticGlobalSpaceRegion>();
706 new (R) StaticGlobalSpaceRegion(this, CR);
707 return R;
708 }
709
getHeapRegion()710 const HeapSpaceRegion *MemRegionManager::getHeapRegion() {
711 return LazyAllocate(heap);
712 }
713
getUnknownRegion()714 const MemSpaceRegion *MemRegionManager::getUnknownRegion() {
715 return LazyAllocate(unknown);
716 }
717
getCodeRegion()718 const MemSpaceRegion *MemRegionManager::getCodeRegion() {
719 return LazyAllocate(code);
720 }
721
722 //===----------------------------------------------------------------------===//
723 // Constructing regions.
724 //===----------------------------------------------------------------------===//
getStringRegion(const StringLiteral * Str)725 const StringRegion* MemRegionManager::getStringRegion(const StringLiteral* Str){
726 return getSubRegion<StringRegion>(Str, getGlobalsRegion());
727 }
728
729 const ObjCStringRegion *
getObjCStringRegion(const ObjCStringLiteral * Str)730 MemRegionManager::getObjCStringRegion(const ObjCStringLiteral* Str){
731 return getSubRegion<ObjCStringRegion>(Str, getGlobalsRegion());
732 }
733
734 /// Look through a chain of LocationContexts to either find the
735 /// StackFrameContext that matches a DeclContext, or find a VarRegion
736 /// for a variable captured by a block.
737 static llvm::PointerUnion<const StackFrameContext *, const VarRegion *>
getStackOrCaptureRegionForDeclContext(const LocationContext * LC,const DeclContext * DC,const VarDecl * VD)738 getStackOrCaptureRegionForDeclContext(const LocationContext *LC,
739 const DeclContext *DC,
740 const VarDecl *VD) {
741 while (LC) {
742 if (const StackFrameContext *SFC = dyn_cast<StackFrameContext>(LC)) {
743 if (cast<DeclContext>(SFC->getDecl()) == DC)
744 return SFC;
745 }
746 if (const BlockInvocationContext *BC =
747 dyn_cast<BlockInvocationContext>(LC)) {
748 const BlockDataRegion *BR =
749 static_cast<const BlockDataRegion*>(BC->getContextData());
750 // FIXME: This can be made more efficient.
751 for (BlockDataRegion::referenced_vars_iterator
752 I = BR->referenced_vars_begin(),
753 E = BR->referenced_vars_end(); I != E; ++I) {
754 if (const VarRegion *VR = dyn_cast<VarRegion>(I.getOriginalRegion()))
755 if (VR->getDecl() == VD)
756 return cast<VarRegion>(I.getCapturedRegion());
757 }
758 }
759
760 LC = LC->getParent();
761 }
762 return (const StackFrameContext *)nullptr;
763 }
764
getVarRegion(const VarDecl * D,const LocationContext * LC)765 const VarRegion* MemRegionManager::getVarRegion(const VarDecl *D,
766 const LocationContext *LC) {
767 const MemRegion *sReg = nullptr;
768
769 if (D->hasGlobalStorage() && !D->isStaticLocal()) {
770
771 // First handle the globals defined in system headers.
772 if (C.getSourceManager().isInSystemHeader(D->getLocation())) {
773 // Whitelist the system globals which often DO GET modified, assume the
774 // rest are immutable.
775 if (D->getName().find("errno") != StringRef::npos)
776 sReg = getGlobalsRegion(MemRegion::GlobalSystemSpaceRegionKind);
777 else
778 sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
779
780 // Treat other globals as GlobalInternal unless they are constants.
781 } else {
782 QualType GQT = D->getType();
783 const Type *GT = GQT.getTypePtrOrNull();
784 // TODO: We could walk the complex types here and see if everything is
785 // constified.
786 if (GT && GQT.isConstQualified() && GT->isArithmeticType())
787 sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
788 else
789 sReg = getGlobalsRegion();
790 }
791
792 // Finally handle static locals.
793 } else {
794 // FIXME: Once we implement scope handling, we will need to properly lookup
795 // 'D' to the proper LocationContext.
796 const DeclContext *DC = D->getDeclContext();
797 llvm::PointerUnion<const StackFrameContext *, const VarRegion *> V =
798 getStackOrCaptureRegionForDeclContext(LC, DC, D);
799
800 if (V.is<const VarRegion*>())
801 return V.get<const VarRegion*>();
802
803 const StackFrameContext *STC = V.get<const StackFrameContext*>();
804
805 if (!STC)
806 sReg = getUnknownRegion();
807 else {
808 if (D->hasLocalStorage()) {
809 sReg = isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)
810 ? static_cast<const MemRegion*>(getStackArgumentsRegion(STC))
811 : static_cast<const MemRegion*>(getStackLocalsRegion(STC));
812 }
813 else {
814 assert(D->isStaticLocal());
815 const Decl *STCD = STC->getDecl();
816 if (isa<FunctionDecl>(STCD) || isa<ObjCMethodDecl>(STCD))
817 sReg = getGlobalsRegion(MemRegion::StaticGlobalSpaceRegionKind,
818 getFunctionTextRegion(cast<NamedDecl>(STCD)));
819 else if (const BlockDecl *BD = dyn_cast<BlockDecl>(STCD)) {
820 // FIXME: The fallback type here is totally bogus -- though it should
821 // never be queried, it will prevent uniquing with the real
822 // BlockTextRegion. Ideally we'd fix the AST so that we always had a
823 // signature.
824 QualType T;
825 if (const TypeSourceInfo *TSI = BD->getSignatureAsWritten())
826 T = TSI->getType();
827 else
828 T = getContext().getFunctionNoProtoType(getContext().VoidTy);
829
830 const BlockTextRegion *BTR =
831 getBlockTextRegion(BD, C.getCanonicalType(T),
832 STC->getAnalysisDeclContext());
833 sReg = getGlobalsRegion(MemRegion::StaticGlobalSpaceRegionKind,
834 BTR);
835 }
836 else {
837 sReg = getGlobalsRegion();
838 }
839 }
840 }
841 }
842
843 return getSubRegion<VarRegion>(D, sReg);
844 }
845
getVarRegion(const VarDecl * D,const MemRegion * superR)846 const VarRegion *MemRegionManager::getVarRegion(const VarDecl *D,
847 const MemRegion *superR) {
848 return getSubRegion<VarRegion>(D, superR);
849 }
850
851 const BlockDataRegion *
getBlockDataRegion(const BlockTextRegion * BC,const LocationContext * LC,unsigned blockCount)852 MemRegionManager::getBlockDataRegion(const BlockTextRegion *BC,
853 const LocationContext *LC,
854 unsigned blockCount) {
855 const MemRegion *sReg = nullptr;
856 const BlockDecl *BD = BC->getDecl();
857 if (!BD->hasCaptures()) {
858 // This handles 'static' blocks.
859 sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
860 }
861 else {
862 if (LC) {
863 // FIXME: Once we implement scope handling, we want the parent region
864 // to be the scope.
865 const StackFrameContext *STC = LC->getCurrentStackFrame();
866 assert(STC);
867 sReg = getStackLocalsRegion(STC);
868 }
869 else {
870 // We allow 'LC' to be NULL for cases where want BlockDataRegions
871 // without context-sensitivity.
872 sReg = getUnknownRegion();
873 }
874 }
875
876 return getSubRegion<BlockDataRegion>(BC, LC, blockCount, sReg);
877 }
878
879 const CXXTempObjectRegion *
getCXXStaticTempObjectRegion(const Expr * Ex)880 MemRegionManager::getCXXStaticTempObjectRegion(const Expr *Ex) {
881 return getSubRegion<CXXTempObjectRegion>(
882 Ex, getGlobalsRegion(MemRegion::GlobalInternalSpaceRegionKind, nullptr));
883 }
884
885 const CompoundLiteralRegion*
getCompoundLiteralRegion(const CompoundLiteralExpr * CL,const LocationContext * LC)886 MemRegionManager::getCompoundLiteralRegion(const CompoundLiteralExpr *CL,
887 const LocationContext *LC) {
888
889 const MemRegion *sReg = nullptr;
890
891 if (CL->isFileScope())
892 sReg = getGlobalsRegion();
893 else {
894 const StackFrameContext *STC = LC->getCurrentStackFrame();
895 assert(STC);
896 sReg = getStackLocalsRegion(STC);
897 }
898
899 return getSubRegion<CompoundLiteralRegion>(CL, sReg);
900 }
901
902 const ElementRegion*
getElementRegion(QualType elementType,NonLoc Idx,const MemRegion * superRegion,ASTContext & Ctx)903 MemRegionManager::getElementRegion(QualType elementType, NonLoc Idx,
904 const MemRegion* superRegion,
905 ASTContext &Ctx){
906
907 QualType T = Ctx.getCanonicalType(elementType).getUnqualifiedType();
908
909 llvm::FoldingSetNodeID ID;
910 ElementRegion::ProfileRegion(ID, T, Idx, superRegion);
911
912 void *InsertPos;
913 MemRegion* data = Regions.FindNodeOrInsertPos(ID, InsertPos);
914 ElementRegion* R = cast_or_null<ElementRegion>(data);
915
916 if (!R) {
917 R = (ElementRegion*) A.Allocate<ElementRegion>();
918 new (R) ElementRegion(T, Idx, superRegion);
919 Regions.InsertNode(R, InsertPos);
920 }
921
922 return R;
923 }
924
925 const FunctionTextRegion *
getFunctionTextRegion(const NamedDecl * FD)926 MemRegionManager::getFunctionTextRegion(const NamedDecl *FD) {
927 return getSubRegion<FunctionTextRegion>(FD, getCodeRegion());
928 }
929
930 const BlockTextRegion *
getBlockTextRegion(const BlockDecl * BD,CanQualType locTy,AnalysisDeclContext * AC)931 MemRegionManager::getBlockTextRegion(const BlockDecl *BD, CanQualType locTy,
932 AnalysisDeclContext *AC) {
933 return getSubRegion<BlockTextRegion>(BD, locTy, AC, getCodeRegion());
934 }
935
936
937 /// getSymbolicRegion - Retrieve or create a "symbolic" memory region.
getSymbolicRegion(SymbolRef sym)938 const SymbolicRegion *MemRegionManager::getSymbolicRegion(SymbolRef sym) {
939 return getSubRegion<SymbolicRegion>(sym, getUnknownRegion());
940 }
941
getSymbolicHeapRegion(SymbolRef Sym)942 const SymbolicRegion *MemRegionManager::getSymbolicHeapRegion(SymbolRef Sym) {
943 return getSubRegion<SymbolicRegion>(Sym, getHeapRegion());
944 }
945
946 const FieldRegion*
getFieldRegion(const FieldDecl * d,const MemRegion * superRegion)947 MemRegionManager::getFieldRegion(const FieldDecl *d,
948 const MemRegion* superRegion){
949 return getSubRegion<FieldRegion>(d, superRegion);
950 }
951
952 const ObjCIvarRegion*
getObjCIvarRegion(const ObjCIvarDecl * d,const MemRegion * superRegion)953 MemRegionManager::getObjCIvarRegion(const ObjCIvarDecl *d,
954 const MemRegion* superRegion) {
955 return getSubRegion<ObjCIvarRegion>(d, superRegion);
956 }
957
958 const CXXTempObjectRegion*
getCXXTempObjectRegion(Expr const * E,LocationContext const * LC)959 MemRegionManager::getCXXTempObjectRegion(Expr const *E,
960 LocationContext const *LC) {
961 const StackFrameContext *SFC = LC->getCurrentStackFrame();
962 assert(SFC);
963 return getSubRegion<CXXTempObjectRegion>(E, getStackLocalsRegion(SFC));
964 }
965
966 /// Checks whether \p BaseClass is a valid virtual or direct non-virtual base
967 /// class of the type of \p Super.
isValidBaseClass(const CXXRecordDecl * BaseClass,const TypedValueRegion * Super,bool IsVirtual)968 static bool isValidBaseClass(const CXXRecordDecl *BaseClass,
969 const TypedValueRegion *Super,
970 bool IsVirtual) {
971 BaseClass = BaseClass->getCanonicalDecl();
972
973 const CXXRecordDecl *Class = Super->getValueType()->getAsCXXRecordDecl();
974 if (!Class)
975 return true;
976
977 if (IsVirtual)
978 return Class->isVirtuallyDerivedFrom(BaseClass);
979
980 for (const auto &I : Class->bases()) {
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 nullptr;
1117 }
1118
getAsArrayOffset() const1119 RegionRawOffset ElementRegion::getAsArrayOffset() const {
1120 CharUnits offset = CharUnits::Zero();
1121 const ElementRegion *ER = this;
1122 const MemRegion *superR = nullptr;
1123 ASTContext &C = getContext();
1124
1125 // FIXME: Handle multi-dimensional arrays.
1126
1127 while (ER) {
1128 superR = ER->getSuperRegion();
1129
1130 // FIXME: generalize to symbolic offsets.
1131 SVal index = ER->getIndex();
1132 if (Optional<nonloc::ConcreteInt> CI = index.getAs<nonloc::ConcreteInt>()) {
1133 // Update the offset.
1134 int64_t i = CI->getValue().getSExtValue();
1135
1136 if (i != 0) {
1137 QualType elemType = ER->getElementType();
1138
1139 // If we are pointing to an incomplete type, go no further.
1140 if (elemType->isIncompleteType()) {
1141 superR = ER;
1142 break;
1143 }
1144
1145 CharUnits size = C.getTypeSizeInChars(elemType);
1146 offset += (i * size);
1147 }
1148
1149 // Go to the next ElementRegion (if any).
1150 ER = dyn_cast<ElementRegion>(superR);
1151 continue;
1152 }
1153
1154 return nullptr;
1155 }
1156
1157 assert(superR && "super region cannot be NULL");
1158 return RegionRawOffset(superR, offset);
1159 }
1160
1161
1162 /// Returns true if \p Base is an immediate base class of \p Child
isImmediateBase(const CXXRecordDecl * Child,const CXXRecordDecl * Base)1163 static bool isImmediateBase(const CXXRecordDecl *Child,
1164 const CXXRecordDecl *Base) {
1165 // Note that we do NOT canonicalize the base class here, because
1166 // ASTRecordLayout doesn't either. If that leads us down the wrong path,
1167 // so be it; at least we won't crash.
1168 for (const auto &I : Child->bases()) {
1169 if (I.getType()->getAsCXXRecordDecl() == Base)
1170 return true;
1171 }
1172
1173 return false;
1174 }
1175
getAsOffset() const1176 RegionOffset MemRegion::getAsOffset() const {
1177 const MemRegion *R = this;
1178 const MemRegion *SymbolicOffsetBase = nullptr;
1179 int64_t Offset = 0;
1180
1181 while (1) {
1182 switch (R->getKind()) {
1183 case GenericMemSpaceRegionKind:
1184 case StackLocalsSpaceRegionKind:
1185 case StackArgumentsSpaceRegionKind:
1186 case HeapSpaceRegionKind:
1187 case UnknownSpaceRegionKind:
1188 case StaticGlobalSpaceRegionKind:
1189 case GlobalInternalSpaceRegionKind:
1190 case GlobalSystemSpaceRegionKind:
1191 case GlobalImmutableSpaceRegionKind:
1192 // Stores can bind directly to a region space to set a default value.
1193 assert(Offset == 0 && !SymbolicOffsetBase);
1194 goto Finish;
1195
1196 case FunctionTextRegionKind:
1197 case BlockTextRegionKind:
1198 case BlockDataRegionKind:
1199 // These will never have bindings, but may end up having values requested
1200 // if the user does some strange casting.
1201 if (Offset != 0)
1202 SymbolicOffsetBase = R;
1203 goto Finish;
1204
1205 case SymbolicRegionKind:
1206 case AllocaRegionKind:
1207 case CompoundLiteralRegionKind:
1208 case CXXThisRegionKind:
1209 case StringRegionKind:
1210 case ObjCStringRegionKind:
1211 case VarRegionKind:
1212 case CXXTempObjectRegionKind:
1213 // Usual base regions.
1214 goto Finish;
1215
1216 case ObjCIvarRegionKind:
1217 // This is a little strange, but it's a compromise between
1218 // ObjCIvarRegions having unknown compile-time offsets (when using the
1219 // non-fragile runtime) and yet still being distinct, non-overlapping
1220 // regions. Thus we treat them as "like" base regions for the purposes
1221 // of computing offsets.
1222 goto Finish;
1223
1224 case CXXBaseObjectRegionKind: {
1225 const CXXBaseObjectRegion *BOR = cast<CXXBaseObjectRegion>(R);
1226 R = BOR->getSuperRegion();
1227
1228 QualType Ty;
1229 bool RootIsSymbolic = false;
1230 if (const TypedValueRegion *TVR = dyn_cast<TypedValueRegion>(R)) {
1231 Ty = TVR->getDesugaredValueType(getContext());
1232 } else if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) {
1233 // If our base region is symbolic, we don't know what type it really is.
1234 // Pretend the type of the symbol is the true dynamic type.
1235 // (This will at least be self-consistent for the life of the symbol.)
1236 Ty = SR->getSymbol()->getType()->getPointeeType();
1237 RootIsSymbolic = true;
1238 }
1239
1240 const CXXRecordDecl *Child = Ty->getAsCXXRecordDecl();
1241 if (!Child) {
1242 // We cannot compute the offset of the base class.
1243 SymbolicOffsetBase = R;
1244 }
1245
1246 if (RootIsSymbolic) {
1247 // Base layers on symbolic regions may not be type-correct.
1248 // Double-check the inheritance here, and revert to a symbolic offset
1249 // if it's invalid (e.g. due to a reinterpret_cast).
1250 if (BOR->isVirtual()) {
1251 if (!Child->isVirtuallyDerivedFrom(BOR->getDecl()))
1252 SymbolicOffsetBase = R;
1253 } else {
1254 if (!isImmediateBase(Child, BOR->getDecl()))
1255 SymbolicOffsetBase = R;
1256 }
1257 }
1258
1259 // Don't bother calculating precise offsets if we already have a
1260 // symbolic offset somewhere in the chain.
1261 if (SymbolicOffsetBase)
1262 continue;
1263
1264 CharUnits BaseOffset;
1265 const ASTRecordLayout &Layout = getContext().getASTRecordLayout(Child);
1266 if (BOR->isVirtual())
1267 BaseOffset = Layout.getVBaseClassOffset(BOR->getDecl());
1268 else
1269 BaseOffset = Layout.getBaseClassOffset(BOR->getDecl());
1270
1271 // The base offset is in chars, not in bits.
1272 Offset += BaseOffset.getQuantity() * getContext().getCharWidth();
1273 break;
1274 }
1275 case ElementRegionKind: {
1276 const ElementRegion *ER = cast<ElementRegion>(R);
1277 R = ER->getSuperRegion();
1278
1279 QualType EleTy = ER->getValueType();
1280 if (EleTy->isIncompleteType()) {
1281 // We cannot compute the offset of the base class.
1282 SymbolicOffsetBase = R;
1283 continue;
1284 }
1285
1286 SVal Index = ER->getIndex();
1287 if (Optional<nonloc::ConcreteInt> CI =
1288 Index.getAs<nonloc::ConcreteInt>()) {
1289 // Don't bother calculating precise offsets if we already have a
1290 // symbolic offset somewhere in the chain.
1291 if (SymbolicOffsetBase)
1292 continue;
1293
1294 int64_t i = CI->getValue().getSExtValue();
1295 // This type size is in bits.
1296 Offset += i * getContext().getTypeSize(EleTy);
1297 } else {
1298 // We cannot compute offset for non-concrete index.
1299 SymbolicOffsetBase = R;
1300 }
1301 break;
1302 }
1303 case FieldRegionKind: {
1304 const FieldRegion *FR = cast<FieldRegion>(R);
1305 R = FR->getSuperRegion();
1306
1307 const RecordDecl *RD = FR->getDecl()->getParent();
1308 if (RD->isUnion() || !RD->isCompleteDefinition()) {
1309 // We cannot compute offset for incomplete type.
1310 // For unions, we could treat everything as offset 0, but we'd rather
1311 // treat each field as a symbolic offset so they aren't stored on top
1312 // of each other, since we depend on things in typed regions actually
1313 // matching their types.
1314 SymbolicOffsetBase = R;
1315 }
1316
1317 // Don't bother calculating precise offsets if we already have a
1318 // symbolic offset somewhere in the chain.
1319 if (SymbolicOffsetBase)
1320 continue;
1321
1322 // Get the field number.
1323 unsigned idx = 0;
1324 for (RecordDecl::field_iterator FI = RD->field_begin(),
1325 FE = RD->field_end(); FI != FE; ++FI, ++idx)
1326 if (FR->getDecl() == *FI)
1327 break;
1328
1329 const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
1330 // This is offset in bits.
1331 Offset += Layout.getFieldOffset(idx);
1332 break;
1333 }
1334 }
1335 }
1336
1337 Finish:
1338 if (SymbolicOffsetBase)
1339 return RegionOffset(SymbolicOffsetBase, RegionOffset::Symbolic);
1340 return RegionOffset(R, Offset);
1341 }
1342
1343 //===----------------------------------------------------------------------===//
1344 // BlockDataRegion
1345 //===----------------------------------------------------------------------===//
1346
1347 std::pair<const VarRegion *, const VarRegion *>
getCaptureRegions(const VarDecl * VD)1348 BlockDataRegion::getCaptureRegions(const VarDecl *VD) {
1349 MemRegionManager &MemMgr = *getMemRegionManager();
1350 const VarRegion *VR = nullptr;
1351 const VarRegion *OriginalVR = nullptr;
1352
1353 if (!VD->hasAttr<BlocksAttr>() && VD->hasLocalStorage()) {
1354 VR = MemMgr.getVarRegion(VD, this);
1355 OriginalVR = MemMgr.getVarRegion(VD, LC);
1356 }
1357 else {
1358 if (LC) {
1359 VR = MemMgr.getVarRegion(VD, LC);
1360 OriginalVR = VR;
1361 }
1362 else {
1363 VR = MemMgr.getVarRegion(VD, MemMgr.getUnknownRegion());
1364 OriginalVR = MemMgr.getVarRegion(VD, LC);
1365 }
1366 }
1367 return std::make_pair(VR, OriginalVR);
1368 }
1369
LazyInitializeReferencedVars()1370 void BlockDataRegion::LazyInitializeReferencedVars() {
1371 if (ReferencedVars)
1372 return;
1373
1374 AnalysisDeclContext *AC = getCodeRegion()->getAnalysisDeclContext();
1375 const auto &ReferencedBlockVars = AC->getReferencedBlockVars(BC->getDecl());
1376 auto NumBlockVars =
1377 std::distance(ReferencedBlockVars.begin(), ReferencedBlockVars.end());
1378
1379 if (NumBlockVars == 0) {
1380 ReferencedVars = (void*) 0x1;
1381 return;
1382 }
1383
1384 MemRegionManager &MemMgr = *getMemRegionManager();
1385 llvm::BumpPtrAllocator &A = MemMgr.getAllocator();
1386 BumpVectorContext BC(A);
1387
1388 typedef BumpVector<const MemRegion*> VarVec;
1389 VarVec *BV = (VarVec*) A.Allocate<VarVec>();
1390 new (BV) VarVec(BC, NumBlockVars);
1391 VarVec *BVOriginal = (VarVec*) A.Allocate<VarVec>();
1392 new (BVOriginal) VarVec(BC, NumBlockVars);
1393
1394 for (const VarDecl *VD : ReferencedBlockVars) {
1395 const VarRegion *VR = nullptr;
1396 const VarRegion *OriginalVR = nullptr;
1397 std::tie(VR, OriginalVR) = getCaptureRegions(VD);
1398 assert(VR);
1399 assert(OriginalVR);
1400 BV->push_back(VR, BC);
1401 BVOriginal->push_back(OriginalVR, BC);
1402 }
1403
1404 ReferencedVars = BV;
1405 OriginalVars = BVOriginal;
1406 }
1407
1408 BlockDataRegion::referenced_vars_iterator
referenced_vars_begin() const1409 BlockDataRegion::referenced_vars_begin() const {
1410 const_cast<BlockDataRegion*>(this)->LazyInitializeReferencedVars();
1411
1412 BumpVector<const MemRegion*> *Vec =
1413 static_cast<BumpVector<const MemRegion*>*>(ReferencedVars);
1414
1415 if (Vec == (void*) 0x1)
1416 return BlockDataRegion::referenced_vars_iterator(nullptr, nullptr);
1417
1418 BumpVector<const MemRegion*> *VecOriginal =
1419 static_cast<BumpVector<const MemRegion*>*>(OriginalVars);
1420
1421 return BlockDataRegion::referenced_vars_iterator(Vec->begin(),
1422 VecOriginal->begin());
1423 }
1424
1425 BlockDataRegion::referenced_vars_iterator
referenced_vars_end() const1426 BlockDataRegion::referenced_vars_end() const {
1427 const_cast<BlockDataRegion*>(this)->LazyInitializeReferencedVars();
1428
1429 BumpVector<const MemRegion*> *Vec =
1430 static_cast<BumpVector<const MemRegion*>*>(ReferencedVars);
1431
1432 if (Vec == (void*) 0x1)
1433 return BlockDataRegion::referenced_vars_iterator(nullptr, nullptr);
1434
1435 BumpVector<const MemRegion*> *VecOriginal =
1436 static_cast<BumpVector<const MemRegion*>*>(OriginalVars);
1437
1438 return BlockDataRegion::referenced_vars_iterator(Vec->end(),
1439 VecOriginal->end());
1440 }
1441
getOriginalRegion(const VarRegion * R) const1442 const VarRegion *BlockDataRegion::getOriginalRegion(const VarRegion *R) const {
1443 for (referenced_vars_iterator I = referenced_vars_begin(),
1444 E = referenced_vars_end();
1445 I != E; ++I) {
1446 if (I.getCapturedRegion() == R)
1447 return I.getOriginalRegion();
1448 }
1449 return nullptr;
1450 }
1451
1452 //===----------------------------------------------------------------------===//
1453 // RegionAndSymbolInvalidationTraits
1454 //===----------------------------------------------------------------------===//
1455
setTrait(SymbolRef Sym,InvalidationKinds IK)1456 void RegionAndSymbolInvalidationTraits::setTrait(SymbolRef Sym,
1457 InvalidationKinds IK) {
1458 SymTraitsMap[Sym] |= IK;
1459 }
1460
setTrait(const MemRegion * MR,InvalidationKinds IK)1461 void RegionAndSymbolInvalidationTraits::setTrait(const MemRegion *MR,
1462 InvalidationKinds IK) {
1463 assert(MR);
1464 if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(MR))
1465 setTrait(SR->getSymbol(), IK);
1466 else
1467 MRTraitsMap[MR] |= IK;
1468 }
1469
hasTrait(SymbolRef Sym,InvalidationKinds IK)1470 bool RegionAndSymbolInvalidationTraits::hasTrait(SymbolRef Sym,
1471 InvalidationKinds IK) {
1472 const_symbol_iterator I = SymTraitsMap.find(Sym);
1473 if (I != SymTraitsMap.end())
1474 return I->second & IK;
1475
1476 return false;
1477 }
1478
hasTrait(const MemRegion * MR,InvalidationKinds IK)1479 bool RegionAndSymbolInvalidationTraits::hasTrait(const MemRegion *MR,
1480 InvalidationKinds IK) {
1481 if (!MR)
1482 return false;
1483
1484 if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(MR))
1485 return hasTrait(SR->getSymbol(), IK);
1486
1487 const_region_iterator I = MRTraitsMap.find(MR);
1488 if (I != MRTraitsMap.end())
1489 return I->second & IK;
1490
1491 return false;
1492 }
1493