clang  3.7.0
RegionStore.cpp
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1 //== RegionStore.cpp - Field-sensitive store model --------------*- 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 a basic region store model. In this model, we do have field
11 // sensitivity. But we assume nothing about the heap shape. So recursive data
12 // structures are largely ignored. Basically we do 1-limiting analysis.
13 // Parameter pointers are assumed with no aliasing. Pointee objects of
14 // parameters are created lazily.
15 //
16 //===----------------------------------------------------------------------===//
17 #include "clang/AST/Attr.h"
18 #include "clang/AST/CharUnits.h"
21 #include "clang/Basic/TargetInfo.h"
28 #include "llvm/ADT/ImmutableList.h"
29 #include "llvm/ADT/ImmutableMap.h"
30 #include "llvm/ADT/Optional.h"
31 #include "llvm/Support/raw_ostream.h"
32 
33 using namespace clang;
34 using namespace ento;
35 
36 //===----------------------------------------------------------------------===//
37 // Representation of binding keys.
38 //===----------------------------------------------------------------------===//
39 
40 namespace {
41 class BindingKey {
42 public:
43  enum Kind { Default = 0x0, Direct = 0x1 };
44 private:
45  enum { Symbolic = 0x2 };
46 
47  llvm::PointerIntPair<const MemRegion *, 2> P;
48  uint64_t Data;
49 
50  /// Create a key for a binding to region \p r, which has a symbolic offset
51  /// from region \p Base.
52  explicit BindingKey(const SubRegion *r, const SubRegion *Base, Kind k)
53  : P(r, k | Symbolic), Data(reinterpret_cast<uintptr_t>(Base)) {
54  assert(r && Base && "Must have known regions.");
55  assert(getConcreteOffsetRegion() == Base && "Failed to store base region");
56  }
57 
58  /// Create a key for a binding at \p offset from base region \p r.
59  explicit BindingKey(const MemRegion *r, uint64_t offset, Kind k)
60  : P(r, k), Data(offset) {
61  assert(r && "Must have known regions.");
62  assert(getOffset() == offset && "Failed to store offset");
63  assert((r == r->getBaseRegion() || isa<ObjCIvarRegion>(r)) && "Not a base");
64  }
65 public:
66 
67  bool isDirect() const { return P.getInt() & Direct; }
68  bool hasSymbolicOffset() const { return P.getInt() & Symbolic; }
69 
70  const MemRegion *getRegion() const { return P.getPointer(); }
71  uint64_t getOffset() const {
72  assert(!hasSymbolicOffset());
73  return Data;
74  }
75 
76  const SubRegion *getConcreteOffsetRegion() const {
77  assert(hasSymbolicOffset());
78  return reinterpret_cast<const SubRegion *>(static_cast<uintptr_t>(Data));
79  }
80 
81  const MemRegion *getBaseRegion() const {
82  if (hasSymbolicOffset())
83  return getConcreteOffsetRegion()->getBaseRegion();
84  return getRegion()->getBaseRegion();
85  }
86 
87  void Profile(llvm::FoldingSetNodeID& ID) const {
88  ID.AddPointer(P.getOpaqueValue());
89  ID.AddInteger(Data);
90  }
91 
92  static BindingKey Make(const MemRegion *R, Kind k);
93 
94  bool operator<(const BindingKey &X) const {
95  if (P.getOpaqueValue() < X.P.getOpaqueValue())
96  return true;
97  if (P.getOpaqueValue() > X.P.getOpaqueValue())
98  return false;
99  return Data < X.Data;
100  }
101 
102  bool operator==(const BindingKey &X) const {
103  return P.getOpaqueValue() == X.P.getOpaqueValue() &&
104  Data == X.Data;
105  }
106 
107  void dump() const;
108 };
109 } // end anonymous namespace
110 
111 BindingKey BindingKey::Make(const MemRegion *R, Kind k) {
112  const RegionOffset &RO = R->getAsOffset();
113  if (RO.hasSymbolicOffset())
114  return BindingKey(cast<SubRegion>(R), cast<SubRegion>(RO.getRegion()), k);
115 
116  return BindingKey(RO.getRegion(), RO.getOffset(), k);
117 }
118 
119 namespace llvm {
120  static inline
121  raw_ostream &operator<<(raw_ostream &os, BindingKey K) {
122  os << '(' << K.getRegion();
123  if (!K.hasSymbolicOffset())
124  os << ',' << K.getOffset();
125  os << ',' << (K.isDirect() ? "direct" : "default")
126  << ')';
127  return os;
128  }
129 
130  template <typename T> struct isPodLike;
131  template <> struct isPodLike<BindingKey> {
132  static const bool value = true;
133  };
134 } // end llvm namespace
135 
136 LLVM_DUMP_METHOD void BindingKey::dump() const { llvm::errs() << *this; }
137 
138 //===----------------------------------------------------------------------===//
139 // Actual Store type.
140 //===----------------------------------------------------------------------===//
141 
143 typedef llvm::ImmutableMapRef<BindingKey, SVal> ClusterBindingsRef;
144 typedef std::pair<BindingKey, SVal> BindingPair;
145 
148 
149 namespace {
150 class RegionBindingsRef : public llvm::ImmutableMapRef<const MemRegion *,
151  ClusterBindings> {
152  ClusterBindings::Factory &CBFactory;
153 public:
154  typedef llvm::ImmutableMapRef<const MemRegion *, ClusterBindings>
155  ParentTy;
156 
157  RegionBindingsRef(ClusterBindings::Factory &CBFactory,
158  const RegionBindings::TreeTy *T,
159  RegionBindings::TreeTy::Factory *F)
160  : llvm::ImmutableMapRef<const MemRegion *, ClusterBindings>(T, F),
161  CBFactory(CBFactory) {}
162 
163  RegionBindingsRef(const ParentTy &P, ClusterBindings::Factory &CBFactory)
164  : llvm::ImmutableMapRef<const MemRegion *, ClusterBindings>(P),
165  CBFactory(CBFactory) {}
166 
167  RegionBindingsRef add(key_type_ref K, data_type_ref D) const {
168  return RegionBindingsRef(static_cast<const ParentTy*>(this)->add(K, D),
169  CBFactory);
170  }
171 
172  RegionBindingsRef remove(key_type_ref K) const {
173  return RegionBindingsRef(static_cast<const ParentTy*>(this)->remove(K),
174  CBFactory);
175  }
176 
177  RegionBindingsRef addBinding(BindingKey K, SVal V) const;
178 
179  RegionBindingsRef addBinding(const MemRegion *R,
180  BindingKey::Kind k, SVal V) const;
181 
182  RegionBindingsRef &operator=(const RegionBindingsRef &X) {
183  *static_cast<ParentTy*>(this) = X;
184  return *this;
185  }
186 
187  const SVal *lookup(BindingKey K) const;
188  const SVal *lookup(const MemRegion *R, BindingKey::Kind k) const;
189  const ClusterBindings *lookup(const MemRegion *R) const {
190  return static_cast<const ParentTy*>(this)->lookup(R);
191  }
192 
193  RegionBindingsRef removeBinding(BindingKey K);
194 
195  RegionBindingsRef removeBinding(const MemRegion *R,
196  BindingKey::Kind k);
197 
198  RegionBindingsRef removeBinding(const MemRegion *R) {
199  return removeBinding(R, BindingKey::Direct).
200  removeBinding(R, BindingKey::Default);
201  }
202 
203  Optional<SVal> getDirectBinding(const MemRegion *R) const;
204 
205  /// getDefaultBinding - Returns an SVal* representing an optional default
206  /// binding associated with a region and its subregions.
207  Optional<SVal> getDefaultBinding(const MemRegion *R) const;
208 
209  /// Return the internal tree as a Store.
210  Store asStore() const {
211  return asImmutableMap().getRootWithoutRetain();
212  }
213 
214  void dump(raw_ostream &OS, const char *nl) const {
215  for (iterator I = begin(), E = end(); I != E; ++I) {
216  const ClusterBindings &Cluster = I.getData();
217  for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end();
218  CI != CE; ++CI) {
219  OS << ' ' << CI.getKey() << " : " << CI.getData() << nl;
220  }
221  OS << nl;
222  }
223  }
224 
225  LLVM_DUMP_METHOD void dump() const { dump(llvm::errs(), "\n"); }
226 };
227 } // end anonymous namespace
228 
229 typedef const RegionBindingsRef& RegionBindingsConstRef;
230 
231 Optional<SVal> RegionBindingsRef::getDirectBinding(const MemRegion *R) const {
232  return Optional<SVal>::create(lookup(R, BindingKey::Direct));
233 }
234 
235 Optional<SVal> RegionBindingsRef::getDefaultBinding(const MemRegion *R) const {
236  if (R->isBoundable())
237  if (const TypedValueRegion *TR = dyn_cast<TypedValueRegion>(R))
238  if (TR->getValueType()->isUnionType())
239  return UnknownVal();
240 
241  return Optional<SVal>::create(lookup(R, BindingKey::Default));
242 }
243 
244 RegionBindingsRef RegionBindingsRef::addBinding(BindingKey K, SVal V) const {
245  const MemRegion *Base = K.getBaseRegion();
246 
247  const ClusterBindings *ExistingCluster = lookup(Base);
248  ClusterBindings Cluster = (ExistingCluster ? *ExistingCluster
249  : CBFactory.getEmptyMap());
250 
251  ClusterBindings NewCluster = CBFactory.add(Cluster, K, V);
252  return add(Base, NewCluster);
253 }
254 
255 
256 RegionBindingsRef RegionBindingsRef::addBinding(const MemRegion *R,
257  BindingKey::Kind k,
258  SVal V) const {
259  return addBinding(BindingKey::Make(R, k), V);
260 }
261 
262 const SVal *RegionBindingsRef::lookup(BindingKey K) const {
263  const ClusterBindings *Cluster = lookup(K.getBaseRegion());
264  if (!Cluster)
265  return nullptr;
266  return Cluster->lookup(K);
267 }
268 
269 const SVal *RegionBindingsRef::lookup(const MemRegion *R,
270  BindingKey::Kind k) const {
271  return lookup(BindingKey::Make(R, k));
272 }
273 
274 RegionBindingsRef RegionBindingsRef::removeBinding(BindingKey K) {
275  const MemRegion *Base = K.getBaseRegion();
276  const ClusterBindings *Cluster = lookup(Base);
277  if (!Cluster)
278  return *this;
279 
280  ClusterBindings NewCluster = CBFactory.remove(*Cluster, K);
281  if (NewCluster.isEmpty())
282  return remove(Base);
283  return add(Base, NewCluster);
284 }
285 
286 RegionBindingsRef RegionBindingsRef::removeBinding(const MemRegion *R,
287  BindingKey::Kind k){
288  return removeBinding(BindingKey::Make(R, k));
289 }
290 
291 //===----------------------------------------------------------------------===//
292 // Fine-grained control of RegionStoreManager.
293 //===----------------------------------------------------------------------===//
294 
295 namespace {
296 struct minimal_features_tag {};
297 struct maximal_features_tag {};
298 
299 class RegionStoreFeatures {
300  bool SupportsFields;
301 public:
302  RegionStoreFeatures(minimal_features_tag) :
303  SupportsFields(false) {}
304 
305  RegionStoreFeatures(maximal_features_tag) :
306  SupportsFields(true) {}
307 
308  void enableFields(bool t) { SupportsFields = t; }
309 
310  bool supportsFields() const { return SupportsFields; }
311 };
312 }
313 
314 //===----------------------------------------------------------------------===//
315 // Main RegionStore logic.
316 //===----------------------------------------------------------------------===//
317 
318 namespace {
319 class invalidateRegionsWorker;
320 
321 class RegionStoreManager : public StoreManager {
322 public:
323  const RegionStoreFeatures Features;
324 
325  RegionBindings::Factory RBFactory;
326  mutable ClusterBindings::Factory CBFactory;
327 
328  typedef std::vector<SVal> SValListTy;
329 private:
330  typedef llvm::DenseMap<const LazyCompoundValData *,
331  SValListTy> LazyBindingsMapTy;
332  LazyBindingsMapTy LazyBindingsMap;
333 
334  /// The largest number of fields a struct can have and still be
335  /// considered "small".
336  ///
337  /// This is currently used to decide whether or not it is worth "forcing" a
338  /// LazyCompoundVal on bind.
339  ///
340  /// This is controlled by 'region-store-small-struct-limit' option.
341  /// To disable all small-struct-dependent behavior, set the option to "0".
342  unsigned SmallStructLimit;
343 
344  /// \brief A helper used to populate the work list with the given set of
345  /// regions.
346  void populateWorkList(invalidateRegionsWorker &W,
347  ArrayRef<SVal> Values,
348  InvalidatedRegions *TopLevelRegions);
349 
350 public:
351  RegionStoreManager(ProgramStateManager& mgr, const RegionStoreFeatures &f)
352  : StoreManager(mgr), Features(f),
353  RBFactory(mgr.getAllocator()), CBFactory(mgr.getAllocator()),
354  SmallStructLimit(0) {
355  if (SubEngine *Eng = StateMgr.getOwningEngine()) {
356  AnalyzerOptions &Options = Eng->getAnalysisManager().options;
357  SmallStructLimit =
358  Options.getOptionAsInteger("region-store-small-struct-limit", 2);
359  }
360  }
361 
362 
363  /// setImplicitDefaultValue - Set the default binding for the provided
364  /// MemRegion to the value implicitly defined for compound literals when
365  /// the value is not specified.
366  RegionBindingsRef setImplicitDefaultValue(RegionBindingsConstRef B,
367  const MemRegion *R, QualType T);
368 
369  /// ArrayToPointer - Emulates the "decay" of an array to a pointer
370  /// type. 'Array' represents the lvalue of the array being decayed
371  /// to a pointer, and the returned SVal represents the decayed
372  /// version of that lvalue (i.e., a pointer to the first element of
373  /// the array). This is called by ExprEngine when evaluating
374  /// casts from arrays to pointers.
375  SVal ArrayToPointer(Loc Array, QualType ElementTy) override;
376 
377  StoreRef getInitialStore(const LocationContext *InitLoc) override {
378  return StoreRef(RBFactory.getEmptyMap().getRootWithoutRetain(), *this);
379  }
380 
381  //===-------------------------------------------------------------------===//
382  // Binding values to regions.
383  //===-------------------------------------------------------------------===//
384  RegionBindingsRef invalidateGlobalRegion(MemRegion::Kind K,
385  const Expr *Ex,
386  unsigned Count,
387  const LocationContext *LCtx,
388  RegionBindingsRef B,
389  InvalidatedRegions *Invalidated);
390 
391  StoreRef invalidateRegions(Store store,
392  ArrayRef<SVal> Values,
393  const Expr *E, unsigned Count,
394  const LocationContext *LCtx,
395  const CallEvent *Call,
396  InvalidatedSymbols &IS,
398  InvalidatedRegions *Invalidated,
399  InvalidatedRegions *InvalidatedTopLevel) override;
400 
401  bool scanReachableSymbols(Store S, const MemRegion *R,
402  ScanReachableSymbols &Callbacks) override;
403 
404  RegionBindingsRef removeSubRegionBindings(RegionBindingsConstRef B,
405  const SubRegion *R);
406 
407 public: // Part of public interface to class.
408 
409  StoreRef Bind(Store store, Loc LV, SVal V) override {
410  return StoreRef(bind(getRegionBindings(store), LV, V).asStore(), *this);
411  }
412 
413  RegionBindingsRef bind(RegionBindingsConstRef B, Loc LV, SVal V);
414 
415  // BindDefault is only used to initialize a region with a default value.
416  StoreRef BindDefault(Store store, const MemRegion *R, SVal V) override {
417  RegionBindingsRef B = getRegionBindings(store);
418  assert(!B.lookup(R, BindingKey::Direct));
419 
420  BindingKey Key = BindingKey::Make(R, BindingKey::Default);
421  if (B.lookup(Key)) {
422  const SubRegion *SR = cast<SubRegion>(R);
423  assert(SR->getAsOffset().getOffset() ==
424  SR->getSuperRegion()->getAsOffset().getOffset() &&
425  "A default value must come from a super-region");
426  B = removeSubRegionBindings(B, SR);
427  } else {
428  B = B.addBinding(Key, V);
429  }
430 
431  return StoreRef(B.asImmutableMap().getRootWithoutRetain(), *this);
432  }
433 
434  /// Attempt to extract the fields of \p LCV and bind them to the struct region
435  /// \p R.
436  ///
437  /// This path is used when it seems advantageous to "force" loading the values
438  /// within a LazyCompoundVal to bind memberwise to the struct region, rather
439  /// than using a Default binding at the base of the entire region. This is a
440  /// heuristic attempting to avoid building long chains of LazyCompoundVals.
441  ///
442  /// \returns The updated store bindings, or \c None if binding non-lazily
443  /// would be too expensive.
445  const TypedValueRegion *R,
446  const RecordDecl *RD,
448 
449  /// BindStruct - Bind a compound value to a structure.
450  RegionBindingsRef bindStruct(RegionBindingsConstRef B,
451  const TypedValueRegion* R, SVal V);
452 
453  /// BindVector - Bind a compound value to a vector.
454  RegionBindingsRef bindVector(RegionBindingsConstRef B,
455  const TypedValueRegion* R, SVal V);
456 
457  RegionBindingsRef bindArray(RegionBindingsConstRef B,
458  const TypedValueRegion* R,
459  SVal V);
460 
461  /// Clears out all bindings in the given region and assigns a new value
462  /// as a Default binding.
463  RegionBindingsRef bindAggregate(RegionBindingsConstRef B,
464  const TypedRegion *R,
465  SVal DefaultVal);
466 
467  /// \brief Create a new store with the specified binding removed.
468  /// \param ST the original store, that is the basis for the new store.
469  /// \param L the location whose binding should be removed.
470  StoreRef killBinding(Store ST, Loc L) override;
471 
472  void incrementReferenceCount(Store store) override {
473  getRegionBindings(store).manualRetain();
474  }
475 
476  /// If the StoreManager supports it, decrement the reference count of
477  /// the specified Store object. If the reference count hits 0, the memory
478  /// associated with the object is recycled.
479  void decrementReferenceCount(Store store) override {
480  getRegionBindings(store).manualRelease();
481  }
482 
483  bool includedInBindings(Store store, const MemRegion *region) const override;
484 
485  /// \brief Return the value bound to specified location in a given state.
486  ///
487  /// The high level logic for this method is this:
488  /// getBinding (L)
489  /// if L has binding
490  /// return L's binding
491  /// else if L is in killset
492  /// return unknown
493  /// else
494  /// if L is on stack or heap
495  /// return undefined
496  /// else
497  /// return symbolic
498  SVal getBinding(Store S, Loc L, QualType T) override {
499  return getBinding(getRegionBindings(S), L, T);
500  }
501 
502  SVal getBinding(RegionBindingsConstRef B, Loc L, QualType T = QualType());
503 
504  SVal getBindingForElement(RegionBindingsConstRef B, const ElementRegion *R);
505 
506  SVal getBindingForField(RegionBindingsConstRef B, const FieldRegion *R);
507 
508  SVal getBindingForObjCIvar(RegionBindingsConstRef B, const ObjCIvarRegion *R);
509 
510  SVal getBindingForVar(RegionBindingsConstRef B, const VarRegion *R);
511 
512  SVal getBindingForLazySymbol(const TypedValueRegion *R);
513 
514  SVal getBindingForFieldOrElementCommon(RegionBindingsConstRef B,
515  const TypedValueRegion *R,
516  QualType Ty);
517 
518  SVal getLazyBinding(const SubRegion *LazyBindingRegion,
519  RegionBindingsRef LazyBinding);
520 
521  /// Get bindings for the values in a struct and return a CompoundVal, used
522  /// when doing struct copy:
523  /// struct s x, y;
524  /// x = y;
525  /// y's value is retrieved by this method.
526  SVal getBindingForStruct(RegionBindingsConstRef B, const TypedValueRegion *R);
527  SVal getBindingForArray(RegionBindingsConstRef B, const TypedValueRegion *R);
528  NonLoc createLazyBinding(RegionBindingsConstRef B, const TypedValueRegion *R);
529 
530  /// Used to lazily generate derived symbols for bindings that are defined
531  /// implicitly by default bindings in a super region.
532  ///
533  /// Note that callers may need to specially handle LazyCompoundVals, which
534  /// are returned as is in case the caller needs to treat them differently.
535  Optional<SVal> getBindingForDerivedDefaultValue(RegionBindingsConstRef B,
536  const MemRegion *superR,
537  const TypedValueRegion *R,
538  QualType Ty);
539 
540  /// Get the state and region whose binding this region \p R corresponds to.
541  ///
542  /// If there is no lazy binding for \p R, the returned value will have a null
543  /// \c second. Note that a null pointer can represents a valid Store.
544  std::pair<Store, const SubRegion *>
545  findLazyBinding(RegionBindingsConstRef B, const SubRegion *R,
546  const SubRegion *originalRegion);
547 
548  /// Returns the cached set of interesting SVals contained within a lazy
549  /// binding.
550  ///
551  /// The precise value of "interesting" is determined for the purposes of
552  /// RegionStore's internal analysis. It must always contain all regions and
553  /// symbols, but may omit constants and other kinds of SVal.
554  const SValListTy &getInterestingValues(nonloc::LazyCompoundVal LCV);
555 
556  //===------------------------------------------------------------------===//
557  // State pruning.
558  //===------------------------------------------------------------------===//
559 
560  /// removeDeadBindings - Scans the RegionStore of 'state' for dead values.
561  /// It returns a new Store with these values removed.
562  StoreRef removeDeadBindings(Store store, const StackFrameContext *LCtx,
563  SymbolReaper& SymReaper) override;
564 
565  //===------------------------------------------------------------------===//
566  // Region "extents".
567  //===------------------------------------------------------------------===//
568 
569  // FIXME: This method will soon be eliminated; see the note in Store.h.
570  DefinedOrUnknownSVal getSizeInElements(ProgramStateRef state,
571  const MemRegion* R,
572  QualType EleTy) override;
573 
574  //===------------------------------------------------------------------===//
575  // Utility methods.
576  //===------------------------------------------------------------------===//
577 
578  RegionBindingsRef getRegionBindings(Store store) const {
579  return RegionBindingsRef(CBFactory,
580  static_cast<const RegionBindings::TreeTy*>(store),
581  RBFactory.getTreeFactory());
582  }
583 
584  void print(Store store, raw_ostream &Out, const char* nl,
585  const char *sep) override;
586 
587  void iterBindings(Store store, BindingsHandler& f) override {
588  RegionBindingsRef B = getRegionBindings(store);
589  for (RegionBindingsRef::iterator I = B.begin(), E = B.end(); I != E; ++I) {
590  const ClusterBindings &Cluster = I.getData();
591  for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end();
592  CI != CE; ++CI) {
593  const BindingKey &K = CI.getKey();
594  if (!K.isDirect())
595  continue;
596  if (const SubRegion *R = dyn_cast<SubRegion>(K.getRegion())) {
597  // FIXME: Possibly incorporate the offset?
598  if (!f.HandleBinding(*this, store, R, CI.getData()))
599  return;
600  }
601  }
602  }
603  }
604 };
605 
606 } // end anonymous namespace
607 
608 //===----------------------------------------------------------------------===//
609 // RegionStore creation.
610 //===----------------------------------------------------------------------===//
611 
612 std::unique_ptr<StoreManager>
614  RegionStoreFeatures F = maximal_features_tag();
615  return llvm::make_unique<RegionStoreManager>(StMgr, F);
616 }
617 
618 std::unique_ptr<StoreManager>
620  RegionStoreFeatures F = minimal_features_tag();
621  F.enableFields(true);
622  return llvm::make_unique<RegionStoreManager>(StMgr, F);
623 }
624 
625 
626 //===----------------------------------------------------------------------===//
627 // Region Cluster analysis.
628 //===----------------------------------------------------------------------===//
629 
630 namespace {
631 /// Used to determine which global regions are automatically included in the
632 /// initial worklist of a ClusterAnalysis.
634  /// Don't include any global regions.
635  GFK_None,
636  /// Only include system globals.
637  GFK_SystemOnly,
638  /// Include all global regions.
639  GFK_All
640 };
641 
642 template <typename DERIVED>
643 class ClusterAnalysis {
644 protected:
645  typedef llvm::DenseMap<const MemRegion *, const ClusterBindings *> ClusterMap;
646  typedef const MemRegion * WorkListElement;
648 
649  llvm::SmallPtrSet<const ClusterBindings *, 16> Visited;
650 
651  WorkList WL;
652 
653  RegionStoreManager &RM;
654  ASTContext &Ctx;
655  SValBuilder &svalBuilder;
656 
657  RegionBindingsRef B;
658 
659 private:
660  GlobalsFilterKind GlobalsFilter;
661 
662 protected:
663  const ClusterBindings *getCluster(const MemRegion *R) {
664  return B.lookup(R);
665  }
666 
667  /// Returns true if the memory space of the given region is one of the global
668  /// regions specially included at the start of analysis.
669  bool isInitiallyIncludedGlobalRegion(const MemRegion *R) {
670  switch (GlobalsFilter) {
671  case GFK_None:
672  return false;
673  case GFK_SystemOnly:
674  return isa<GlobalSystemSpaceRegion>(R->getMemorySpace());
675  case GFK_All:
676  return isa<NonStaticGlobalSpaceRegion>(R->getMemorySpace());
677  }
678 
679  llvm_unreachable("unknown globals filter");
680  }
681 
682 public:
683  ClusterAnalysis(RegionStoreManager &rm, ProgramStateManager &StateMgr,
684  RegionBindingsRef b, GlobalsFilterKind GFK)
685  : RM(rm), Ctx(StateMgr.getContext()),
686  svalBuilder(StateMgr.getSValBuilder()),
687  B(b), GlobalsFilter(GFK) {}
688 
689  RegionBindingsRef getRegionBindings() const { return B; }
690 
691  bool isVisited(const MemRegion *R) {
692  return Visited.count(getCluster(R));
693  }
694 
695  void GenerateClusters() {
696  // Scan the entire set of bindings and record the region clusters.
697  for (RegionBindingsRef::iterator RI = B.begin(), RE = B.end();
698  RI != RE; ++RI){
699  const MemRegion *Base = RI.getKey();
700 
701  const ClusterBindings &Cluster = RI.getData();
702  assert(!Cluster.isEmpty() && "Empty clusters should be removed");
703  static_cast<DERIVED*>(this)->VisitAddedToCluster(Base, Cluster);
704 
705  // If this is an interesting global region, add it the work list up front.
706  if (isInitiallyIncludedGlobalRegion(Base))
707  AddToWorkList(WorkListElement(Base), &Cluster);
708  }
709  }
710 
711  bool AddToWorkList(WorkListElement E, const ClusterBindings *C) {
712  if (C && !Visited.insert(C).second)
713  return false;
714  WL.push_back(E);
715  return true;
716  }
717 
718  bool AddToWorkList(const MemRegion *R) {
719  const MemRegion *BaseR = R->getBaseRegion();
720  return AddToWorkList(WorkListElement(BaseR), getCluster(BaseR));
721  }
722 
723  void RunWorkList() {
724  while (!WL.empty()) {
725  WorkListElement E = WL.pop_back_val();
726  const MemRegion *BaseR = E;
727 
728  static_cast<DERIVED*>(this)->VisitCluster(BaseR, getCluster(BaseR));
729  }
730  }
731 
732  void VisitAddedToCluster(const MemRegion *baseR, const ClusterBindings &C) {}
733  void VisitCluster(const MemRegion *baseR, const ClusterBindings *C) {}
734 
735  void VisitCluster(const MemRegion *BaseR, const ClusterBindings *C,
736  bool Flag) {
737  static_cast<DERIVED*>(this)->VisitCluster(BaseR, C);
738  }
739 };
740 }
741 
742 //===----------------------------------------------------------------------===//
743 // Binding invalidation.
744 //===----------------------------------------------------------------------===//
745 
746 bool RegionStoreManager::scanReachableSymbols(Store S, const MemRegion *R,
747  ScanReachableSymbols &Callbacks) {
748  assert(R == R->getBaseRegion() && "Should only be called for base regions");
749  RegionBindingsRef B = getRegionBindings(S);
750  const ClusterBindings *Cluster = B.lookup(R);
751 
752  if (!Cluster)
753  return true;
754 
755  for (ClusterBindings::iterator RI = Cluster->begin(), RE = Cluster->end();
756  RI != RE; ++RI) {
757  if (!Callbacks.scan(RI.getData()))
758  return false;
759  }
760 
761  return true;
762 }
763 
764 static inline bool isUnionField(const FieldRegion *FR) {
765  return FR->getDecl()->getParent()->isUnion();
766 }
767 
769 
770 static void getSymbolicOffsetFields(BindingKey K, FieldVector &Fields) {
771  assert(K.hasSymbolicOffset() && "Not implemented for concrete offset keys");
772 
773  const MemRegion *Base = K.getConcreteOffsetRegion();
774  const MemRegion *R = K.getRegion();
775 
776  while (R != Base) {
777  if (const FieldRegion *FR = dyn_cast<FieldRegion>(R))
778  if (!isUnionField(FR))
779  Fields.push_back(FR->getDecl());
780 
781  R = cast<SubRegion>(R)->getSuperRegion();
782  }
783 }
784 
785 static bool isCompatibleWithFields(BindingKey K, const FieldVector &Fields) {
786  assert(K.hasSymbolicOffset() && "Not implemented for concrete offset keys");
787 
788  if (Fields.empty())
789  return true;
790 
791  FieldVector FieldsInBindingKey;
792  getSymbolicOffsetFields(K, FieldsInBindingKey);
793 
794  ptrdiff_t Delta = FieldsInBindingKey.size() - Fields.size();
795  if (Delta >= 0)
796  return std::equal(FieldsInBindingKey.begin() + Delta,
797  FieldsInBindingKey.end(),
798  Fields.begin());
799  else
800  return std::equal(FieldsInBindingKey.begin(), FieldsInBindingKey.end(),
801  Fields.begin() - Delta);
802 }
803 
804 /// Collects all bindings in \p Cluster that may refer to bindings within
805 /// \p Top.
806 ///
807 /// Each binding is a pair whose \c first is the key (a BindingKey) and whose
808 /// \c second is the value (an SVal).
809 ///
810 /// The \p IncludeAllDefaultBindings parameter specifies whether to include
811 /// default bindings that may extend beyond \p Top itself, e.g. if \p Top is
812 /// an aggregate within a larger aggregate with a default binding.
813 static void
815  SValBuilder &SVB, const ClusterBindings &Cluster,
816  const SubRegion *Top, BindingKey TopKey,
817  bool IncludeAllDefaultBindings) {
818  FieldVector FieldsInSymbolicSubregions;
819  if (TopKey.hasSymbolicOffset()) {
820  getSymbolicOffsetFields(TopKey, FieldsInSymbolicSubregions);
821  Top = cast<SubRegion>(TopKey.getConcreteOffsetRegion());
822  TopKey = BindingKey::Make(Top, BindingKey::Default);
823  }
824 
825  // Find the length (in bits) of the region being invalidated.
826  uint64_t Length = UINT64_MAX;
827  SVal Extent = Top->getExtent(SVB);
828  if (Optional<nonloc::ConcreteInt> ExtentCI =
829  Extent.getAs<nonloc::ConcreteInt>()) {
830  const llvm::APSInt &ExtentInt = ExtentCI->getValue();
831  assert(ExtentInt.isNonNegative() || ExtentInt.isUnsigned());
832  // Extents are in bytes but region offsets are in bits. Be careful!
833  Length = ExtentInt.getLimitedValue() * SVB.getContext().getCharWidth();
834  } else if (const FieldRegion *FR = dyn_cast<FieldRegion>(Top)) {
835  if (FR->getDecl()->isBitField())
836  Length = FR->getDecl()->getBitWidthValue(SVB.getContext());
837  }
838 
839  for (ClusterBindings::iterator I = Cluster.begin(), E = Cluster.end();
840  I != E; ++I) {
841  BindingKey NextKey = I.getKey();
842  if (NextKey.getRegion() == TopKey.getRegion()) {
843  // FIXME: This doesn't catch the case where we're really invalidating a
844  // region with a symbolic offset. Example:
845  // R: points[i].y
846  // Next: points[0].x
847 
848  if (NextKey.getOffset() > TopKey.getOffset() &&
849  NextKey.getOffset() - TopKey.getOffset() < Length) {
850  // Case 1: The next binding is inside the region we're invalidating.
851  // Include it.
852  Bindings.push_back(*I);
853 
854  } else if (NextKey.getOffset() == TopKey.getOffset()) {
855  // Case 2: The next binding is at the same offset as the region we're
856  // invalidating. In this case, we need to leave default bindings alone,
857  // since they may be providing a default value for a regions beyond what
858  // we're invalidating.
859  // FIXME: This is probably incorrect; consider invalidating an outer
860  // struct whose first field is bound to a LazyCompoundVal.
861  if (IncludeAllDefaultBindings || NextKey.isDirect())
862  Bindings.push_back(*I);
863  }
864 
865  } else if (NextKey.hasSymbolicOffset()) {
866  const MemRegion *Base = NextKey.getConcreteOffsetRegion();
867  if (Top->isSubRegionOf(Base)) {
868  // Case 3: The next key is symbolic and we just changed something within
869  // its concrete region. We don't know if the binding is still valid, so
870  // we'll be conservative and include it.
871  if (IncludeAllDefaultBindings || NextKey.isDirect())
872  if (isCompatibleWithFields(NextKey, FieldsInSymbolicSubregions))
873  Bindings.push_back(*I);
874  } else if (const SubRegion *BaseSR = dyn_cast<SubRegion>(Base)) {
875  // Case 4: The next key is symbolic, but we changed a known
876  // super-region. In this case the binding is certainly included.
877  if (Top == Base || BaseSR->isSubRegionOf(Top))
878  if (isCompatibleWithFields(NextKey, FieldsInSymbolicSubregions))
879  Bindings.push_back(*I);
880  }
881  }
882  }
883 }
884 
885 static void
887  SValBuilder &SVB, const ClusterBindings &Cluster,
888  const SubRegion *Top, bool IncludeAllDefaultBindings) {
889  collectSubRegionBindings(Bindings, SVB, Cluster, Top,
890  BindingKey::Make(Top, BindingKey::Default),
891  IncludeAllDefaultBindings);
892 }
893 
894 RegionBindingsRef
895 RegionStoreManager::removeSubRegionBindings(RegionBindingsConstRef B,
896  const SubRegion *Top) {
897  BindingKey TopKey = BindingKey::Make(Top, BindingKey::Default);
898  const MemRegion *ClusterHead = TopKey.getBaseRegion();
899 
900  if (Top == ClusterHead) {
901  // We can remove an entire cluster's bindings all in one go.
902  return B.remove(Top);
903  }
904 
905  const ClusterBindings *Cluster = B.lookup(ClusterHead);
906  if (!Cluster) {
907  // If we're invalidating a region with a symbolic offset, we need to make
908  // sure we don't treat the base region as uninitialized anymore.
909  if (TopKey.hasSymbolicOffset()) {
910  const SubRegion *Concrete = TopKey.getConcreteOffsetRegion();
911  return B.addBinding(Concrete, BindingKey::Default, UnknownVal());
912  }
913  return B;
914  }
915 
917  collectSubRegionBindings(Bindings, svalBuilder, *Cluster, Top, TopKey,
918  /*IncludeAllDefaultBindings=*/false);
919 
920  ClusterBindingsRef Result(*Cluster, CBFactory);
921  for (SmallVectorImpl<BindingPair>::const_iterator I = Bindings.begin(),
922  E = Bindings.end();
923  I != E; ++I)
924  Result = Result.remove(I->first);
925 
926  // If we're invalidating a region with a symbolic offset, we need to make sure
927  // we don't treat the base region as uninitialized anymore.
928  // FIXME: This isn't very precise; see the example in
929  // collectSubRegionBindings.
930  if (TopKey.hasSymbolicOffset()) {
931  const SubRegion *Concrete = TopKey.getConcreteOffsetRegion();
932  Result = Result.add(BindingKey::Make(Concrete, BindingKey::Default),
933  UnknownVal());
934  }
935 
936  if (Result.isEmpty())
937  return B.remove(ClusterHead);
938  return B.add(ClusterHead, Result.asImmutableMap());
939 }
940 
941 namespace {
942 class invalidateRegionsWorker : public ClusterAnalysis<invalidateRegionsWorker>
943 {
944  const Expr *Ex;
945  unsigned Count;
946  const LocationContext *LCtx;
947  InvalidatedSymbols &IS;
950 public:
951  invalidateRegionsWorker(RegionStoreManager &rm,
952  ProgramStateManager &stateMgr,
953  RegionBindingsRef b,
954  const Expr *ex, unsigned count,
955  const LocationContext *lctx,
956  InvalidatedSymbols &is,
959  GlobalsFilterKind GFK)
960  : ClusterAnalysis<invalidateRegionsWorker>(rm, stateMgr, b, GFK),
961  Ex(ex), Count(count), LCtx(lctx), IS(is), ITraits(ITraitsIn), Regions(r){}
962 
963  void VisitCluster(const MemRegion *baseR, const ClusterBindings *C);
964  void VisitBinding(SVal V);
965 };
966 }
967 
968 void invalidateRegionsWorker::VisitBinding(SVal V) {
969  // A symbol? Mark it touched by the invalidation.
970  if (SymbolRef Sym = V.getAsSymbol())
971  IS.insert(Sym);
972 
973  if (const MemRegion *R = V.getAsRegion()) {
974  AddToWorkList(R);
975  return;
976  }
977 
978  // Is it a LazyCompoundVal? All references get invalidated as well.
981 
982  const RegionStoreManager::SValListTy &Vals = RM.getInterestingValues(*LCS);
983 
984  for (RegionStoreManager::SValListTy::const_iterator I = Vals.begin(),
985  E = Vals.end();
986  I != E; ++I)
987  VisitBinding(*I);
988 
989  return;
990  }
991 }
992 
993 void invalidateRegionsWorker::VisitCluster(const MemRegion *baseR,
994  const ClusterBindings *C) {
995 
996  bool PreserveRegionsContents =
997  ITraits.hasTrait(baseR,
999 
1000  if (C) {
1001  for (ClusterBindings::iterator I = C->begin(), E = C->end(); I != E; ++I)
1002  VisitBinding(I.getData());
1003 
1004  // Invalidate regions contents.
1005  if (!PreserveRegionsContents)
1006  B = B.remove(baseR);
1007  }
1008 
1009  // BlockDataRegion? If so, invalidate captured variables that are passed
1010  // by reference.
1011  if (const BlockDataRegion *BR = dyn_cast<BlockDataRegion>(baseR)) {
1013  BI = BR->referenced_vars_begin(), BE = BR->referenced_vars_end() ;
1014  BI != BE; ++BI) {
1015  const VarRegion *VR = BI.getCapturedRegion();
1016  const VarDecl *VD = VR->getDecl();
1017  if (VD->hasAttr<BlocksAttr>() || !VD->hasLocalStorage()) {
1018  AddToWorkList(VR);
1019  }
1020  else if (Loc::isLocType(VR->getValueType())) {
1021  // Map the current bindings to a Store to retrieve the value
1022  // of the binding. If that binding itself is a region, we should
1023  // invalidate that region. This is because a block may capture
1024  // a pointer value, but the thing pointed by that pointer may
1025  // get invalidated.
1026  SVal V = RM.getBinding(B, loc::MemRegionVal(VR));
1027  if (Optional<Loc> L = V.getAs<Loc>()) {
1028  if (const MemRegion *LR = L->getAsRegion())
1029  AddToWorkList(LR);
1030  }
1031  }
1032  }
1033  return;
1034  }
1035 
1036  // Symbolic region?
1037  if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(baseR))
1038  IS.insert(SR->getSymbol());
1039 
1040  // Nothing else should be done in the case when we preserve regions context.
1041  if (PreserveRegionsContents)
1042  return;
1043 
1044  // Otherwise, we have a normal data region. Record that we touched the region.
1045  if (Regions)
1046  Regions->push_back(baseR);
1047 
1048  if (isa<AllocaRegion>(baseR) || isa<SymbolicRegion>(baseR)) {
1049  // Invalidate the region by setting its default value to
1050  // conjured symbol. The type of the symbol is irrelevant.
1052  svalBuilder.conjureSymbolVal(baseR, Ex, LCtx, Ctx.IntTy, Count);
1053  B = B.addBinding(baseR, BindingKey::Default, V);
1054  return;
1055  }
1056 
1057  if (!baseR->isBoundable())
1058  return;
1059 
1060  const TypedValueRegion *TR = cast<TypedValueRegion>(baseR);
1061  QualType T = TR->getValueType();
1062 
1063  if (isInitiallyIncludedGlobalRegion(baseR)) {
1064  // If the region is a global and we are invalidating all globals,
1065  // erasing the entry is good enough. This causes all globals to be lazily
1066  // symbolicated from the same base symbol.
1067  return;
1068  }
1069 
1070  if (T->isStructureOrClassType()) {
1071  // Invalidate the region by setting its default value to
1072  // conjured symbol. The type of the symbol is irrelevant.
1073  DefinedOrUnknownSVal V = svalBuilder.conjureSymbolVal(baseR, Ex, LCtx,
1074  Ctx.IntTy, Count);
1075  B = B.addBinding(baseR, BindingKey::Default, V);
1076  return;
1077  }
1078 
1079  if (const ArrayType *AT = Ctx.getAsArrayType(T)) {
1080  // Set the default value of the array to conjured symbol.
1082  svalBuilder.conjureSymbolVal(baseR, Ex, LCtx,
1083  AT->getElementType(), Count);
1084  B = B.addBinding(baseR, BindingKey::Default, V);
1085  return;
1086  }
1087 
1088  DefinedOrUnknownSVal V = svalBuilder.conjureSymbolVal(baseR, Ex, LCtx,
1089  T,Count);
1090  assert(SymbolManager::canSymbolicate(T) || V.isUnknown());
1091  B = B.addBinding(baseR, BindingKey::Direct, V);
1092 }
1093 
1094 RegionBindingsRef
1095 RegionStoreManager::invalidateGlobalRegion(MemRegion::Kind K,
1096  const Expr *Ex,
1097  unsigned Count,
1098  const LocationContext *LCtx,
1099  RegionBindingsRef B,
1100  InvalidatedRegions *Invalidated) {
1101  // Bind the globals memory space to a new symbol that we will use to derive
1102  // the bindings for all globals.
1103  const GlobalsSpaceRegion *GS = MRMgr.getGlobalsRegion(K);
1104  SVal V = svalBuilder.conjureSymbolVal(/* SymbolTag = */ (const void*) GS, Ex, LCtx,
1105  /* type does not matter */ Ctx.IntTy,
1106  Count);
1107 
1108  B = B.removeBinding(GS)
1109  .addBinding(BindingKey::Make(GS, BindingKey::Default), V);
1110 
1111  // Even if there are no bindings in the global scope, we still need to
1112  // record that we touched it.
1113  if (Invalidated)
1114  Invalidated->push_back(GS);
1115 
1116  return B;
1117 }
1118 
1119 void RegionStoreManager::populateWorkList(invalidateRegionsWorker &W,
1120  ArrayRef<SVal> Values,
1121  InvalidatedRegions *TopLevelRegions) {
1122  for (ArrayRef<SVal>::iterator I = Values.begin(),
1123  E = Values.end(); I != E; ++I) {
1124  SVal V = *I;
1127 
1128  const SValListTy &Vals = getInterestingValues(*LCS);
1129 
1130  for (SValListTy::const_iterator I = Vals.begin(),
1131  E = Vals.end(); I != E; ++I) {
1132  // Note: the last argument is false here because these are
1133  // non-top-level regions.
1134  if (const MemRegion *R = (*I).getAsRegion())
1135  W.AddToWorkList(R);
1136  }
1137  continue;
1138  }
1139 
1140  if (const MemRegion *R = V.getAsRegion()) {
1141  if (TopLevelRegions)
1142  TopLevelRegions->push_back(R);
1143  W.AddToWorkList(R);
1144  continue;
1145  }
1146  }
1147 }
1148 
1149 StoreRef
1150 RegionStoreManager::invalidateRegions(Store store,
1151  ArrayRef<SVal> Values,
1152  const Expr *Ex, unsigned Count,
1153  const LocationContext *LCtx,
1154  const CallEvent *Call,
1155  InvalidatedSymbols &IS,
1157  InvalidatedRegions *TopLevelRegions,
1158  InvalidatedRegions *Invalidated) {
1159  GlobalsFilterKind GlobalsFilter;
1160  if (Call) {
1161  if (Call->isInSystemHeader())
1162  GlobalsFilter = GFK_SystemOnly;
1163  else
1164  GlobalsFilter = GFK_All;
1165  } else {
1166  GlobalsFilter = GFK_None;
1167  }
1168 
1169  RegionBindingsRef B = getRegionBindings(store);
1170  invalidateRegionsWorker W(*this, StateMgr, B, Ex, Count, LCtx, IS, ITraits,
1171  Invalidated, GlobalsFilter);
1172 
1173  // Scan the bindings and generate the clusters.
1174  W.GenerateClusters();
1175 
1176  // Add the regions to the worklist.
1177  populateWorkList(W, Values, TopLevelRegions);
1178 
1179  W.RunWorkList();
1180 
1181  // Return the new bindings.
1182  B = W.getRegionBindings();
1183 
1184  // For calls, determine which global regions should be invalidated and
1185  // invalidate them. (Note that function-static and immutable globals are never
1186  // invalidated by this.)
1187  // TODO: This could possibly be more precise with modules.
1188  switch (GlobalsFilter) {
1189  case GFK_All:
1190  B = invalidateGlobalRegion(MemRegion::GlobalInternalSpaceRegionKind,
1191  Ex, Count, LCtx, B, Invalidated);
1192  // FALLTHROUGH
1193  case GFK_SystemOnly:
1194  B = invalidateGlobalRegion(MemRegion::GlobalSystemSpaceRegionKind,
1195  Ex, Count, LCtx, B, Invalidated);
1196  // FALLTHROUGH
1197  case GFK_None:
1198  break;
1199  }
1200 
1201  return StoreRef(B.asStore(), *this);
1202 }
1203 
1204 //===----------------------------------------------------------------------===//
1205 // Extents for regions.
1206 //===----------------------------------------------------------------------===//
1207 
1209 RegionStoreManager::getSizeInElements(ProgramStateRef state,
1210  const MemRegion *R,
1211  QualType EleTy) {
1212  SVal Size = cast<SubRegion>(R)->getExtent(svalBuilder);
1213  const llvm::APSInt *SizeInt = svalBuilder.getKnownValue(state, Size);
1214  if (!SizeInt)
1215  return UnknownVal();
1216 
1217  CharUnits RegionSize = CharUnits::fromQuantity(SizeInt->getSExtValue());
1218 
1219  if (Ctx.getAsVariableArrayType(EleTy)) {
1220  // FIXME: We need to track extra state to properly record the size
1221  // of VLAs. Returning UnknownVal here, however, is a stop-gap so that
1222  // we don't have a divide-by-zero below.
1223  return UnknownVal();
1224  }
1225 
1226  CharUnits EleSize = Ctx.getTypeSizeInChars(EleTy);
1227 
1228  // If a variable is reinterpreted as a type that doesn't fit into a larger
1229  // type evenly, round it down.
1230  // This is a signed value, since it's used in arithmetic with signed indices.
1231  return svalBuilder.makeIntVal(RegionSize / EleSize, false);
1232 }
1233 
1234 //===----------------------------------------------------------------------===//
1235 // Location and region casting.
1236 //===----------------------------------------------------------------------===//
1237 
1238 /// ArrayToPointer - Emulates the "decay" of an array to a pointer
1239 /// type. 'Array' represents the lvalue of the array being decayed
1240 /// to a pointer, and the returned SVal represents the decayed
1241 /// version of that lvalue (i.e., a pointer to the first element of
1242 /// the array). This is called by ExprEngine when evaluating casts
1243 /// from arrays to pointers.
1244 SVal RegionStoreManager::ArrayToPointer(Loc Array, QualType T) {
1245  if (!Array.getAs<loc::MemRegionVal>())
1246  return UnknownVal();
1247 
1248  const MemRegion* R = Array.castAs<loc::MemRegionVal>().getRegion();
1249  NonLoc ZeroIdx = svalBuilder.makeZeroArrayIndex();
1250  return loc::MemRegionVal(MRMgr.getElementRegion(T, ZeroIdx, R, Ctx));
1251 }
1252 
1253 //===----------------------------------------------------------------------===//
1254 // Loading values from regions.
1255 //===----------------------------------------------------------------------===//
1256 
1257 SVal RegionStoreManager::getBinding(RegionBindingsConstRef B, Loc L, QualType T) {
1258  assert(!L.getAs<UnknownVal>() && "location unknown");
1259  assert(!L.getAs<UndefinedVal>() && "location undefined");
1260 
1261  // For access to concrete addresses, return UnknownVal. Checks
1262  // for null dereferences (and similar errors) are done by checkers, not
1263  // the Store.
1264  // FIXME: We can consider lazily symbolicating such memory, but we really
1265  // should defer this when we can reason easily about symbolicating arrays
1266  // of bytes.
1267  if (L.getAs<loc::ConcreteInt>()) {
1268  return UnknownVal();
1269  }
1270  if (!L.getAs<loc::MemRegionVal>()) {
1271  return UnknownVal();
1272  }
1273 
1274  const MemRegion *MR = L.castAs<loc::MemRegionVal>().getRegion();
1275 
1276  if (isa<AllocaRegion>(MR) ||
1277  isa<SymbolicRegion>(MR) ||
1278  isa<CodeTextRegion>(MR)) {
1279  if (T.isNull()) {
1280  if (const TypedRegion *TR = dyn_cast<TypedRegion>(MR))
1281  T = TR->getLocationType();
1282  else {
1283  const SymbolicRegion *SR = cast<SymbolicRegion>(MR);
1284  T = SR->getSymbol()->getType();
1285  }
1286  }
1287  MR = GetElementZeroRegion(MR, T);
1288  }
1289 
1290  // FIXME: Perhaps this method should just take a 'const MemRegion*' argument
1291  // instead of 'Loc', and have the other Loc cases handled at a higher level.
1292  const TypedValueRegion *R = cast<TypedValueRegion>(MR);
1293  QualType RTy = R->getValueType();
1294 
1295  // FIXME: we do not yet model the parts of a complex type, so treat the
1296  // whole thing as "unknown".
1297  if (RTy->isAnyComplexType())
1298  return UnknownVal();
1299 
1300  // FIXME: We should eventually handle funny addressing. e.g.:
1301  //
1302  // int x = ...;
1303  // int *p = &x;
1304  // char *q = (char*) p;
1305  // char c = *q; // returns the first byte of 'x'.
1306  //
1307  // Such funny addressing will occur due to layering of regions.
1308  if (RTy->isStructureOrClassType())
1309  return getBindingForStruct(B, R);
1310 
1311  // FIXME: Handle unions.
1312  if (RTy->isUnionType())
1313  return createLazyBinding(B, R);
1314 
1315  if (RTy->isArrayType()) {
1316  if (RTy->isConstantArrayType())
1317  return getBindingForArray(B, R);
1318  else
1319  return UnknownVal();
1320  }
1321 
1322  // FIXME: handle Vector types.
1323  if (RTy->isVectorType())
1324  return UnknownVal();
1325 
1326  if (const FieldRegion* FR = dyn_cast<FieldRegion>(R))
1327  return CastRetrievedVal(getBindingForField(B, FR), FR, T, false);
1328 
1329  if (const ElementRegion* ER = dyn_cast<ElementRegion>(R)) {
1330  // FIXME: Here we actually perform an implicit conversion from the loaded
1331  // value to the element type. Eventually we want to compose these values
1332  // more intelligently. For example, an 'element' can encompass multiple
1333  // bound regions (e.g., several bound bytes), or could be a subset of
1334  // a larger value.
1335  return CastRetrievedVal(getBindingForElement(B, ER), ER, T, false);
1336  }
1337 
1338  if (const ObjCIvarRegion *IVR = dyn_cast<ObjCIvarRegion>(R)) {
1339  // FIXME: Here we actually perform an implicit conversion from the loaded
1340  // value to the ivar type. What we should model is stores to ivars
1341  // that blow past the extent of the ivar. If the address of the ivar is
1342  // reinterpretted, it is possible we stored a different value that could
1343  // fit within the ivar. Either we need to cast these when storing them
1344  // or reinterpret them lazily (as we do here).
1345  return CastRetrievedVal(getBindingForObjCIvar(B, IVR), IVR, T, false);
1346  }
1347 
1348  if (const VarRegion *VR = dyn_cast<VarRegion>(R)) {
1349  // FIXME: Here we actually perform an implicit conversion from the loaded
1350  // value to the variable type. What we should model is stores to variables
1351  // that blow past the extent of the variable. If the address of the
1352  // variable is reinterpretted, it is possible we stored a different value
1353  // that could fit within the variable. Either we need to cast these when
1354  // storing them or reinterpret them lazily (as we do here).
1355  return CastRetrievedVal(getBindingForVar(B, VR), VR, T, false);
1356  }
1357 
1358  const SVal *V = B.lookup(R, BindingKey::Direct);
1359 
1360  // Check if the region has a binding.
1361  if (V)
1362  return *V;
1363 
1364  // The location does not have a bound value. This means that it has
1365  // the value it had upon its creation and/or entry to the analyzed
1366  // function/method. These are either symbolic values or 'undefined'.
1367  if (R->hasStackNonParametersStorage()) {
1368  // All stack variables are considered to have undefined values
1369  // upon creation. All heap allocated blocks are considered to
1370  // have undefined values as well unless they are explicitly bound
1371  // to specific values.
1372  return UndefinedVal();
1373  }
1374 
1375  // All other values are symbolic.
1376  return svalBuilder.getRegionValueSymbolVal(R);
1377 }
1378 
1380  QualType RegionTy;
1381  if (const TypedValueRegion *TVR = dyn_cast<TypedValueRegion>(R))
1382  RegionTy = TVR->getValueType();
1383 
1384  if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R))
1385  RegionTy = SR->getSymbol()->getType();
1386 
1387  return RegionTy;
1388 }
1389 
1390 /// Checks to see if store \p B has a lazy binding for region \p R.
1391 ///
1392 /// If \p AllowSubregionBindings is \c false, a lazy binding will be rejected
1393 /// if there are additional bindings within \p R.
1394 ///
1395 /// Note that unlike RegionStoreManager::findLazyBinding, this will not search
1396 /// for lazy bindings for super-regions of \p R.
1399  const SubRegion *R, bool AllowSubregionBindings) {
1400  Optional<SVal> V = B.getDefaultBinding(R);
1401  if (!V)
1402  return None;
1403 
1405  if (!LCV)
1406  return None;
1407 
1408  // If the LCV is for a subregion, the types might not match, and we shouldn't
1409  // reuse the binding.
1410  QualType RegionTy = getUnderlyingType(R);
1411  if (!RegionTy.isNull() &&
1412  !RegionTy->isVoidPointerType()) {
1413  QualType SourceRegionTy = LCV->getRegion()->getValueType();
1414  if (!SVB.getContext().hasSameUnqualifiedType(RegionTy, SourceRegionTy))
1415  return None;
1416  }
1417 
1418  if (!AllowSubregionBindings) {
1419  // If there are any other bindings within this region, we shouldn't reuse
1420  // the top-level binding.
1422  collectSubRegionBindings(Bindings, SVB, *B.lookup(R->getBaseRegion()), R,
1423  /*IncludeAllDefaultBindings=*/true);
1424  if (Bindings.size() > 1)
1425  return None;
1426  }
1427 
1428  return *LCV;
1429 }
1430 
1431 
1432 std::pair<Store, const SubRegion *>
1433 RegionStoreManager::findLazyBinding(RegionBindingsConstRef B,
1434  const SubRegion *R,
1435  const SubRegion *originalRegion) {
1436  if (originalRegion != R) {
1438  getExistingLazyBinding(svalBuilder, B, R, true))
1439  return std::make_pair(V->getStore(), V->getRegion());
1440  }
1441 
1442  typedef std::pair<Store, const SubRegion *> StoreRegionPair;
1443  StoreRegionPair Result = StoreRegionPair();
1444 
1445  if (const ElementRegion *ER = dyn_cast<ElementRegion>(R)) {
1446  Result = findLazyBinding(B, cast<SubRegion>(ER->getSuperRegion()),
1447  originalRegion);
1448 
1449  if (Result.second)
1450  Result.second = MRMgr.getElementRegionWithSuper(ER, Result.second);
1451 
1452  } else if (const FieldRegion *FR = dyn_cast<FieldRegion>(R)) {
1453  Result = findLazyBinding(B, cast<SubRegion>(FR->getSuperRegion()),
1454  originalRegion);
1455 
1456  if (Result.second)
1457  Result.second = MRMgr.getFieldRegionWithSuper(FR, Result.second);
1458 
1459  } else if (const CXXBaseObjectRegion *BaseReg =
1460  dyn_cast<CXXBaseObjectRegion>(R)) {
1461  // C++ base object region is another kind of region that we should blast
1462  // through to look for lazy compound value. It is like a field region.
1463  Result = findLazyBinding(B, cast<SubRegion>(BaseReg->getSuperRegion()),
1464  originalRegion);
1465 
1466  if (Result.second)
1467  Result.second = MRMgr.getCXXBaseObjectRegionWithSuper(BaseReg,
1468  Result.second);
1469  }
1470 
1471  return Result;
1472 }
1473 
1474 SVal RegionStoreManager::getBindingForElement(RegionBindingsConstRef B,
1475  const ElementRegion* R) {
1476  // We do not currently model bindings of the CompoundLiteralregion.
1477  if (isa<CompoundLiteralRegion>(R->getBaseRegion()))
1478  return UnknownVal();
1479 
1480  // Check if the region has a binding.
1481  if (const Optional<SVal> &V = B.getDirectBinding(R))
1482  return *V;
1483 
1484  const MemRegion* superR = R->getSuperRegion();
1485 
1486  // Check if the region is an element region of a string literal.
1487  if (const StringRegion *StrR=dyn_cast<StringRegion>(superR)) {
1488  // FIXME: Handle loads from strings where the literal is treated as
1489  // an integer, e.g., *((unsigned int*)"hello")
1490  QualType T = Ctx.getAsArrayType(StrR->getValueType())->getElementType();
1491  if (!Ctx.hasSameUnqualifiedType(T, R->getElementType()))
1492  return UnknownVal();
1493 
1494  const StringLiteral *Str = StrR->getStringLiteral();
1495  SVal Idx = R->getIndex();
1497  int64_t i = CI->getValue().getSExtValue();
1498  // Abort on string underrun. This can be possible by arbitrary
1499  // clients of getBindingForElement().
1500  if (i < 0)
1501  return UndefinedVal();
1502  int64_t length = Str->getLength();
1503  // Technically, only i == length is guaranteed to be null.
1504  // However, such overflows should be caught before reaching this point;
1505  // the only time such an access would be made is if a string literal was
1506  // used to initialize a larger array.
1507  char c = (i >= length) ? '\0' : Str->getCodeUnit(i);
1508  return svalBuilder.makeIntVal(c, T);
1509  }
1510  }
1511 
1512  // Check for loads from a code text region. For such loads, just give up.
1513  if (isa<CodeTextRegion>(superR))
1514  return UnknownVal();
1515 
1516  // Handle the case where we are indexing into a larger scalar object.
1517  // For example, this handles:
1518  // int x = ...
1519  // char *y = &x;
1520  // return *y;
1521  // FIXME: This is a hack, and doesn't do anything really intelligent yet.
1522  const RegionRawOffset &O = R->getAsArrayOffset();
1523 
1524  // If we cannot reason about the offset, return an unknown value.
1525  if (!O.getRegion())
1526  return UnknownVal();
1527 
1528  if (const TypedValueRegion *baseR =
1529  dyn_cast_or_null<TypedValueRegion>(O.getRegion())) {
1530  QualType baseT = baseR->getValueType();
1531  if (baseT->isScalarType()) {
1532  QualType elemT = R->getElementType();
1533  if (elemT->isScalarType()) {
1534  if (Ctx.getTypeSizeInChars(baseT) >= Ctx.getTypeSizeInChars(elemT)) {
1535  if (const Optional<SVal> &V = B.getDirectBinding(superR)) {
1536  if (SymbolRef parentSym = V->getAsSymbol())
1537  return svalBuilder.getDerivedRegionValueSymbolVal(parentSym, R);
1538 
1539  if (V->isUnknownOrUndef())
1540  return *V;
1541  // Other cases: give up. We are indexing into a larger object
1542  // that has some value, but we don't know how to handle that yet.
1543  return UnknownVal();
1544  }
1545  }
1546  }
1547  }
1548  }
1549  return getBindingForFieldOrElementCommon(B, R, R->getElementType());
1550 }
1551 
1552 SVal RegionStoreManager::getBindingForField(RegionBindingsConstRef B,
1553  const FieldRegion* R) {
1554 
1555  // Check if the region has a binding.
1556  if (const Optional<SVal> &V = B.getDirectBinding(R))
1557  return *V;
1558 
1559  QualType Ty = R->getValueType();
1560  return getBindingForFieldOrElementCommon(B, R, Ty);
1561 }
1562 
1564 RegionStoreManager::getBindingForDerivedDefaultValue(RegionBindingsConstRef B,
1565  const MemRegion *superR,
1566  const TypedValueRegion *R,
1567  QualType Ty) {
1568 
1569  if (const Optional<SVal> &D = B.getDefaultBinding(superR)) {
1570  const SVal &val = D.getValue();
1571  if (SymbolRef parentSym = val.getAsSymbol())
1572  return svalBuilder.getDerivedRegionValueSymbolVal(parentSym, R);
1573 
1574  if (val.isZeroConstant())
1575  return svalBuilder.makeZeroVal(Ty);
1576 
1577  if (val.isUnknownOrUndef())
1578  return val;
1579 
1580  // Lazy bindings are usually handled through getExistingLazyBinding().
1581  // We should unify these two code paths at some point.
1582  if (val.getAs<nonloc::LazyCompoundVal>())
1583  return val;
1584 
1585  llvm_unreachable("Unknown default value");
1586  }
1587 
1588  return None;
1589 }
1590 
1591 SVal RegionStoreManager::getLazyBinding(const SubRegion *LazyBindingRegion,
1592  RegionBindingsRef LazyBinding) {
1593  SVal Result;
1594  if (const ElementRegion *ER = dyn_cast<ElementRegion>(LazyBindingRegion))
1595  Result = getBindingForElement(LazyBinding, ER);
1596  else
1597  Result = getBindingForField(LazyBinding,
1598  cast<FieldRegion>(LazyBindingRegion));
1599 
1600  // FIXME: This is a hack to deal with RegionStore's inability to distinguish a
1601  // default value for /part/ of an aggregate from a default value for the
1602  // /entire/ aggregate. The most common case of this is when struct Outer
1603  // has as its first member a struct Inner, which is copied in from a stack
1604  // variable. In this case, even if the Outer's default value is symbolic, 0,
1605  // or unknown, it gets overridden by the Inner's default value of undefined.
1606  //
1607  // This is a general problem -- if the Inner is zero-initialized, the Outer
1608  // will now look zero-initialized. The proper way to solve this is with a
1609  // new version of RegionStore that tracks the extent of a binding as well
1610  // as the offset.
1611  //
1612  // This hack only takes care of the undefined case because that can very
1613  // quickly result in a warning.
1614  if (Result.isUndef())
1615  Result = UnknownVal();
1616 
1617  return Result;
1618 }
1619 
1620 SVal
1621 RegionStoreManager::getBindingForFieldOrElementCommon(RegionBindingsConstRef B,
1622  const TypedValueRegion *R,
1623  QualType Ty) {
1624 
1625  // At this point we have already checked in either getBindingForElement or
1626  // getBindingForField if 'R' has a direct binding.
1627 
1628  // Lazy binding?
1629  Store lazyBindingStore = nullptr;
1630  const SubRegion *lazyBindingRegion = nullptr;
1631  std::tie(lazyBindingStore, lazyBindingRegion) = findLazyBinding(B, R, R);
1632  if (lazyBindingRegion)
1633  return getLazyBinding(lazyBindingRegion,
1634  getRegionBindings(lazyBindingStore));
1635 
1636  // Record whether or not we see a symbolic index. That can completely
1637  // be out of scope of our lookup.
1638  bool hasSymbolicIndex = false;
1639 
1640  // FIXME: This is a hack to deal with RegionStore's inability to distinguish a
1641  // default value for /part/ of an aggregate from a default value for the
1642  // /entire/ aggregate. The most common case of this is when struct Outer
1643  // has as its first member a struct Inner, which is copied in from a stack
1644  // variable. In this case, even if the Outer's default value is symbolic, 0,
1645  // or unknown, it gets overridden by the Inner's default value of undefined.
1646  //
1647  // This is a general problem -- if the Inner is zero-initialized, the Outer
1648  // will now look zero-initialized. The proper way to solve this is with a
1649  // new version of RegionStore that tracks the extent of a binding as well
1650  // as the offset.
1651  //
1652  // This hack only takes care of the undefined case because that can very
1653  // quickly result in a warning.
1654  bool hasPartialLazyBinding = false;
1655 
1656  const SubRegion *SR = dyn_cast<SubRegion>(R);
1657  while (SR) {
1658  const MemRegion *Base = SR->getSuperRegion();
1659  if (Optional<SVal> D = getBindingForDerivedDefaultValue(B, Base, R, Ty)) {
1660  if (D->getAs<nonloc::LazyCompoundVal>()) {
1661  hasPartialLazyBinding = true;
1662  break;
1663  }
1664 
1665  return *D;
1666  }
1667 
1668  if (const ElementRegion *ER = dyn_cast<ElementRegion>(Base)) {
1669  NonLoc index = ER->getIndex();
1670  if (!index.isConstant())
1671  hasSymbolicIndex = true;
1672  }
1673 
1674  // If our super region is a field or element itself, walk up the region
1675  // hierarchy to see if there is a default value installed in an ancestor.
1676  SR = dyn_cast<SubRegion>(Base);
1677  }
1678 
1679  if (R->hasStackNonParametersStorage()) {
1680  if (isa<ElementRegion>(R)) {
1681  // Currently we don't reason specially about Clang-style vectors. Check
1682  // if superR is a vector and if so return Unknown.
1683  if (const TypedValueRegion *typedSuperR =
1684  dyn_cast<TypedValueRegion>(R->getSuperRegion())) {
1685  if (typedSuperR->getValueType()->isVectorType())
1686  return UnknownVal();
1687  }
1688  }
1689 
1690  // FIXME: We also need to take ElementRegions with symbolic indexes into
1691  // account. This case handles both directly accessing an ElementRegion
1692  // with a symbolic offset, but also fields within an element with
1693  // a symbolic offset.
1694  if (hasSymbolicIndex)
1695  return UnknownVal();
1696 
1697  if (!hasPartialLazyBinding)
1698  return UndefinedVal();
1699  }
1700 
1701  // All other values are symbolic.
1702  return svalBuilder.getRegionValueSymbolVal(R);
1703 }
1704 
1705 SVal RegionStoreManager::getBindingForObjCIvar(RegionBindingsConstRef B,
1706  const ObjCIvarRegion* R) {
1707  // Check if the region has a binding.
1708  if (const Optional<SVal> &V = B.getDirectBinding(R))
1709  return *V;
1710 
1711  const MemRegion *superR = R->getSuperRegion();
1712 
1713  // Check if the super region has a default binding.
1714  if (const Optional<SVal> &V = B.getDefaultBinding(superR)) {
1715  if (SymbolRef parentSym = V->getAsSymbol())
1716  return svalBuilder.getDerivedRegionValueSymbolVal(parentSym, R);
1717 
1718  // Other cases: give up.
1719  return UnknownVal();
1720  }
1721 
1722  return getBindingForLazySymbol(R);
1723 }
1724 
1725 SVal RegionStoreManager::getBindingForVar(RegionBindingsConstRef B,
1726  const VarRegion *R) {
1727 
1728  // Check if the region has a binding.
1729  if (const Optional<SVal> &V = B.getDirectBinding(R))
1730  return *V;
1731 
1732  // Lazily derive a value for the VarRegion.
1733  const VarDecl *VD = R->getDecl();
1734  const MemSpaceRegion *MS = R->getMemorySpace();
1735 
1736  // Arguments are always symbolic.
1737  if (isa<StackArgumentsSpaceRegion>(MS))
1738  return svalBuilder.getRegionValueSymbolVal(R);
1739 
1740  // Is 'VD' declared constant? If so, retrieve the constant value.
1741  if (VD->getType().isConstQualified())
1742  if (const Expr *Init = VD->getInit())
1743  if (Optional<SVal> V = svalBuilder.getConstantVal(Init))
1744  return *V;
1745 
1746  // This must come after the check for constants because closure-captured
1747  // constant variables may appear in UnknownSpaceRegion.
1748  if (isa<UnknownSpaceRegion>(MS))
1749  return svalBuilder.getRegionValueSymbolVal(R);
1750 
1751  if (isa<GlobalsSpaceRegion>(MS)) {
1752  QualType T = VD->getType();
1753 
1754  // Function-scoped static variables are default-initialized to 0; if they
1755  // have an initializer, it would have been processed by now.
1756  if (isa<StaticGlobalSpaceRegion>(MS))
1757  return svalBuilder.makeZeroVal(T);
1758 
1759  if (Optional<SVal> V = getBindingForDerivedDefaultValue(B, MS, R, T)) {
1760  assert(!V->getAs<nonloc::LazyCompoundVal>());
1761  return V.getValue();
1762  }
1763 
1764  return svalBuilder.getRegionValueSymbolVal(R);
1765  }
1766 
1767  return UndefinedVal();
1768 }
1769 
1770 SVal RegionStoreManager::getBindingForLazySymbol(const TypedValueRegion *R) {
1771  // All other values are symbolic.
1772  return svalBuilder.getRegionValueSymbolVal(R);
1773 }
1774 
1775 const RegionStoreManager::SValListTy &
1776 RegionStoreManager::getInterestingValues(nonloc::LazyCompoundVal LCV) {
1777  // First, check the cache.
1778  LazyBindingsMapTy::iterator I = LazyBindingsMap.find(LCV.getCVData());
1779  if (I != LazyBindingsMap.end())
1780  return I->second;
1781 
1782  // If we don't have a list of values cached, start constructing it.
1783  SValListTy List;
1784 
1785  const SubRegion *LazyR = LCV.getRegion();
1786  RegionBindingsRef B = getRegionBindings(LCV.getStore());
1787 
1788  // If this region had /no/ bindings at the time, there are no interesting
1789  // values to return.
1790  const ClusterBindings *Cluster = B.lookup(LazyR->getBaseRegion());
1791  if (!Cluster)
1792  return (LazyBindingsMap[LCV.getCVData()] = std::move(List));
1793 
1795  collectSubRegionBindings(Bindings, svalBuilder, *Cluster, LazyR,
1796  /*IncludeAllDefaultBindings=*/true);
1797  for (SmallVectorImpl<BindingPair>::const_iterator I = Bindings.begin(),
1798  E = Bindings.end();
1799  I != E; ++I) {
1800  SVal V = I->second;
1801  if (V.isUnknownOrUndef() || V.isConstant())
1802  continue;
1803 
1804  if (Optional<nonloc::LazyCompoundVal> InnerLCV =
1806  const SValListTy &InnerList = getInterestingValues(*InnerLCV);
1807  List.insert(List.end(), InnerList.begin(), InnerList.end());
1808  continue;
1809  }
1810 
1811  List.push_back(V);
1812  }
1813 
1814  return (LazyBindingsMap[LCV.getCVData()] = std::move(List));
1815 }
1816 
1817 NonLoc RegionStoreManager::createLazyBinding(RegionBindingsConstRef B,
1818  const TypedValueRegion *R) {
1820  getExistingLazyBinding(svalBuilder, B, R, false))
1821  return *V;
1822 
1823  return svalBuilder.makeLazyCompoundVal(StoreRef(B.asStore(), *this), R);
1824 }
1825 
1826 static bool isRecordEmpty(const RecordDecl *RD) {
1827  if (!RD->field_empty())
1828  return false;
1829  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD))
1830  return CRD->getNumBases() == 0;
1831  return true;
1832 }
1833 
1834 SVal RegionStoreManager::getBindingForStruct(RegionBindingsConstRef B,
1835  const TypedValueRegion *R) {
1836  const RecordDecl *RD = R->getValueType()->castAs<RecordType>()->getDecl();
1837  if (!RD->getDefinition() || isRecordEmpty(RD))
1838  return UnknownVal();
1839 
1840  return createLazyBinding(B, R);
1841 }
1842 
1843 SVal RegionStoreManager::getBindingForArray(RegionBindingsConstRef B,
1844  const TypedValueRegion *R) {
1845  assert(Ctx.getAsConstantArrayType(R->getValueType()) &&
1846  "Only constant array types can have compound bindings.");
1847 
1848  return createLazyBinding(B, R);
1849 }
1850 
1851 bool RegionStoreManager::includedInBindings(Store store,
1852  const MemRegion *region) const {
1853  RegionBindingsRef B = getRegionBindings(store);
1854  region = region->getBaseRegion();
1855 
1856  // Quick path: if the base is the head of a cluster, the region is live.
1857  if (B.lookup(region))
1858  return true;
1859 
1860  // Slow path: if the region is the VALUE of any binding, it is live.
1861  for (RegionBindingsRef::iterator RI = B.begin(), RE = B.end(); RI != RE; ++RI) {
1862  const ClusterBindings &Cluster = RI.getData();
1863  for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end();
1864  CI != CE; ++CI) {
1865  const SVal &D = CI.getData();
1866  if (const MemRegion *R = D.getAsRegion())
1867  if (R->getBaseRegion() == region)
1868  return true;
1869  }
1870  }
1871 
1872  return false;
1873 }
1874 
1875 //===----------------------------------------------------------------------===//
1876 // Binding values to regions.
1877 //===----------------------------------------------------------------------===//
1878 
1879 StoreRef RegionStoreManager::killBinding(Store ST, Loc L) {
1881  if (const MemRegion* R = LV->getRegion())
1882  return StoreRef(getRegionBindings(ST).removeBinding(R)
1883  .asImmutableMap()
1884  .getRootWithoutRetain(),
1885  *this);
1886 
1887  return StoreRef(ST, *this);
1888 }
1889 
1890 RegionBindingsRef
1891 RegionStoreManager::bind(RegionBindingsConstRef B, Loc L, SVal V) {
1892  if (L.getAs<loc::ConcreteInt>())
1893  return B;
1894 
1895  // If we get here, the location should be a region.
1896  const MemRegion *R = L.castAs<loc::MemRegionVal>().getRegion();
1897 
1898  // Check if the region is a struct region.
1899  if (const TypedValueRegion* TR = dyn_cast<TypedValueRegion>(R)) {
1900  QualType Ty = TR->getValueType();
1901  if (Ty->isArrayType())
1902  return bindArray(B, TR, V);
1903  if (Ty->isStructureOrClassType())
1904  return bindStruct(B, TR, V);
1905  if (Ty->isVectorType())
1906  return bindVector(B, TR, V);
1907  if (Ty->isUnionType())
1908  return bindAggregate(B, TR, V);
1909  }
1910 
1911  if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) {
1912  // Binding directly to a symbolic region should be treated as binding
1913  // to element 0.
1914  QualType T = SR->getSymbol()->getType();
1915  if (T->isAnyPointerType() || T->isReferenceType())
1916  T = T->getPointeeType();
1917 
1918  R = GetElementZeroRegion(SR, T);
1919  }
1920 
1921  // Clear out bindings that may overlap with this binding.
1922  RegionBindingsRef NewB = removeSubRegionBindings(B, cast<SubRegion>(R));
1923  return NewB.addBinding(BindingKey::Make(R, BindingKey::Direct), V);
1924 }
1925 
1926 RegionBindingsRef
1927 RegionStoreManager::setImplicitDefaultValue(RegionBindingsConstRef B,
1928  const MemRegion *R,
1929  QualType T) {
1930  SVal V;
1931 
1932  if (Loc::isLocType(T))
1933  V = svalBuilder.makeNull();
1934  else if (T->isIntegralOrEnumerationType())
1935  V = svalBuilder.makeZeroVal(T);
1936  else if (T->isStructureOrClassType() || T->isArrayType()) {
1937  // Set the default value to a zero constant when it is a structure
1938  // or array. The type doesn't really matter.
1939  V = svalBuilder.makeZeroVal(Ctx.IntTy);
1940  }
1941  else {
1942  // We can't represent values of this type, but we still need to set a value
1943  // to record that the region has been initialized.
1944  // If this assertion ever fires, a new case should be added above -- we
1945  // should know how to default-initialize any value we can symbolicate.
1946  assert(!SymbolManager::canSymbolicate(T) && "This type is representable");
1947  V = UnknownVal();
1948  }
1949 
1950  return B.addBinding(R, BindingKey::Default, V);
1951 }
1952 
1953 RegionBindingsRef
1954 RegionStoreManager::bindArray(RegionBindingsConstRef B,
1955  const TypedValueRegion* R,
1956  SVal Init) {
1957 
1958  const ArrayType *AT =cast<ArrayType>(Ctx.getCanonicalType(R->getValueType()));
1959  QualType ElementTy = AT->getElementType();
1960  Optional<uint64_t> Size;
1961 
1962  if (const ConstantArrayType* CAT = dyn_cast<ConstantArrayType>(AT))
1963  Size = CAT->getSize().getZExtValue();
1964 
1965  // Check if the init expr is a string literal.
1967  const StringRegion *S = cast<StringRegion>(MRV->getRegion());
1968 
1969  // Treat the string as a lazy compound value.
1970  StoreRef store(B.asStore(), *this);
1971  nonloc::LazyCompoundVal LCV = svalBuilder.makeLazyCompoundVal(store, S)
1973  return bindAggregate(B, R, LCV);
1974  }
1975 
1976  // Handle lazy compound values.
1977  if (Init.getAs<nonloc::LazyCompoundVal>())
1978  return bindAggregate(B, R, Init);
1979 
1980  // Remaining case: explicit compound values.
1981 
1982  if (Init.isUnknown())
1983  return setImplicitDefaultValue(B, R, ElementTy);
1984 
1985  const nonloc::CompoundVal& CV = Init.castAs<nonloc::CompoundVal>();
1986  nonloc::CompoundVal::iterator VI = CV.begin(), VE = CV.end();
1987  uint64_t i = 0;
1988 
1989  RegionBindingsRef NewB(B);
1990 
1991  for (; Size.hasValue() ? i < Size.getValue() : true ; ++i, ++VI) {
1992  // The init list might be shorter than the array length.
1993  if (VI == VE)
1994  break;
1995 
1996  const NonLoc &Idx = svalBuilder.makeArrayIndex(i);
1997  const ElementRegion *ER = MRMgr.getElementRegion(ElementTy, Idx, R, Ctx);
1998 
1999  if (ElementTy->isStructureOrClassType())
2000  NewB = bindStruct(NewB, ER, *VI);
2001  else if (ElementTy->isArrayType())
2002  NewB = bindArray(NewB, ER, *VI);
2003  else
2004  NewB = bind(NewB, loc::MemRegionVal(ER), *VI);
2005  }
2006 
2007  // If the init list is shorter than the array length, set the
2008  // array default value.
2009  if (Size.hasValue() && i < Size.getValue())
2010  NewB = setImplicitDefaultValue(NewB, R, ElementTy);
2011 
2012  return NewB;
2013 }
2014 
2015 RegionBindingsRef RegionStoreManager::bindVector(RegionBindingsConstRef B,
2016  const TypedValueRegion* R,
2017  SVal V) {
2018  QualType T = R->getValueType();
2019  assert(T->isVectorType());
2020  const VectorType *VT = T->getAs<VectorType>(); // Use getAs for typedefs.
2021 
2022  // Handle lazy compound values and symbolic values.
2024  return bindAggregate(B, R, V);
2025 
2026  // We may get non-CompoundVal accidentally due to imprecise cast logic or
2027  // that we are binding symbolic struct value. Kill the field values, and if
2028  // the value is symbolic go and bind it as a "default" binding.
2029  if (!V.getAs<nonloc::CompoundVal>()) {
2030  return bindAggregate(B, R, UnknownVal());
2031  }
2032 
2033  QualType ElemType = VT->getElementType();
2035  nonloc::CompoundVal::iterator VI = CV.begin(), VE = CV.end();
2036  unsigned index = 0, numElements = VT->getNumElements();
2037  RegionBindingsRef NewB(B);
2038 
2039  for ( ; index != numElements ; ++index) {
2040  if (VI == VE)
2041  break;
2042 
2043  NonLoc Idx = svalBuilder.makeArrayIndex(index);
2044  const ElementRegion *ER = MRMgr.getElementRegion(ElemType, Idx, R, Ctx);
2045 
2046  if (ElemType->isArrayType())
2047  NewB = bindArray(NewB, ER, *VI);
2048  else if (ElemType->isStructureOrClassType())
2049  NewB = bindStruct(NewB, ER, *VI);
2050  else
2051  NewB = bind(NewB, loc::MemRegionVal(ER), *VI);
2052  }
2053  return NewB;
2054 }
2055 
2057 RegionStoreManager::tryBindSmallStruct(RegionBindingsConstRef B,
2058  const TypedValueRegion *R,
2059  const RecordDecl *RD,
2061  FieldVector Fields;
2062 
2063  if (const CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(RD))
2064  if (Class->getNumBases() != 0 || Class->getNumVBases() != 0)
2065  return None;
2066 
2067  for (const auto *FD : RD->fields()) {
2068  if (FD->isUnnamedBitfield())
2069  continue;
2070 
2071  // If there are too many fields, or if any of the fields are aggregates,
2072  // just use the LCV as a default binding.
2073  if (Fields.size() == SmallStructLimit)
2074  return None;
2075 
2076  QualType Ty = FD->getType();
2077  if (!(Ty->isScalarType() || Ty->isReferenceType()))
2078  return None;
2079 
2080  Fields.push_back(FD);
2081  }
2082 
2083  RegionBindingsRef NewB = B;
2084 
2085  for (FieldVector::iterator I = Fields.begin(), E = Fields.end(); I != E; ++I){
2086  const FieldRegion *SourceFR = MRMgr.getFieldRegion(*I, LCV.getRegion());
2087  SVal V = getBindingForField(getRegionBindings(LCV.getStore()), SourceFR);
2088 
2089  const FieldRegion *DestFR = MRMgr.getFieldRegion(*I, R);
2090  NewB = bind(NewB, loc::MemRegionVal(DestFR), V);
2091  }
2092 
2093  return NewB;
2094 }
2095 
2096 RegionBindingsRef RegionStoreManager::bindStruct(RegionBindingsConstRef B,
2097  const TypedValueRegion* R,
2098  SVal V) {
2099  if (!Features.supportsFields())
2100  return B;
2101 
2102  QualType T = R->getValueType();
2103  assert(T->isStructureOrClassType());
2104 
2105  const RecordType* RT = T->getAs<RecordType>();
2106  const RecordDecl *RD = RT->getDecl();
2107 
2108  if (!RD->isCompleteDefinition())
2109  return B;
2110 
2111  // Handle lazy compound values and symbolic values.
2114  if (Optional<RegionBindingsRef> NewB = tryBindSmallStruct(B, R, RD, *LCV))
2115  return *NewB;
2116  return bindAggregate(B, R, V);
2117  }
2118  if (V.getAs<nonloc::SymbolVal>())
2119  return bindAggregate(B, R, V);
2120 
2121  // We may get non-CompoundVal accidentally due to imprecise cast logic or
2122  // that we are binding symbolic struct value. Kill the field values, and if
2123  // the value is symbolic go and bind it as a "default" binding.
2124  if (V.isUnknown() || !V.getAs<nonloc::CompoundVal>())
2125  return bindAggregate(B, R, UnknownVal());
2126 
2128  nonloc::CompoundVal::iterator VI = CV.begin(), VE = CV.end();
2129 
2131  RegionBindingsRef NewB(B);
2132 
2133  for (FI = RD->field_begin(), FE = RD->field_end(); FI != FE; ++FI) {
2134 
2135  if (VI == VE)
2136  break;
2137 
2138  // Skip any unnamed bitfields to stay in sync with the initializers.
2139  if (FI->isUnnamedBitfield())
2140  continue;
2141 
2142  QualType FTy = FI->getType();
2143  const FieldRegion* FR = MRMgr.getFieldRegion(*FI, R);
2144 
2145  if (FTy->isArrayType())
2146  NewB = bindArray(NewB, FR, *VI);
2147  else if (FTy->isStructureOrClassType())
2148  NewB = bindStruct(NewB, FR, *VI);
2149  else
2150  NewB = bind(NewB, loc::MemRegionVal(FR), *VI);
2151  ++VI;
2152  }
2153 
2154  // There may be fewer values in the initialize list than the fields of struct.
2155  if (FI != FE) {
2156  NewB = NewB.addBinding(R, BindingKey::Default,
2157  svalBuilder.makeIntVal(0, false));
2158  }
2159 
2160  return NewB;
2161 }
2162 
2163 RegionBindingsRef
2164 RegionStoreManager::bindAggregate(RegionBindingsConstRef B,
2165  const TypedRegion *R,
2166  SVal Val) {
2167  // Remove the old bindings, using 'R' as the root of all regions
2168  // we will invalidate. Then add the new binding.
2169  return removeSubRegionBindings(B, R).addBinding(R, BindingKey::Default, Val);
2170 }
2171 
2172 //===----------------------------------------------------------------------===//
2173 // State pruning.
2174 //===----------------------------------------------------------------------===//
2175 
2176 namespace {
2177 class removeDeadBindingsWorker :
2178  public ClusterAnalysis<removeDeadBindingsWorker> {
2180  SymbolReaper &SymReaper;
2181  const StackFrameContext *CurrentLCtx;
2182 
2183 public:
2184  removeDeadBindingsWorker(RegionStoreManager &rm,
2185  ProgramStateManager &stateMgr,
2186  RegionBindingsRef b, SymbolReaper &symReaper,
2187  const StackFrameContext *LCtx)
2188  : ClusterAnalysis<removeDeadBindingsWorker>(rm, stateMgr, b, GFK_None),
2189  SymReaper(symReaper), CurrentLCtx(LCtx) {}
2190 
2191  // Called by ClusterAnalysis.
2192  void VisitAddedToCluster(const MemRegion *baseR, const ClusterBindings &C);
2193  void VisitCluster(const MemRegion *baseR, const ClusterBindings *C);
2194  using ClusterAnalysis<removeDeadBindingsWorker>::VisitCluster;
2195 
2196  bool UpdatePostponed();
2197  void VisitBinding(SVal V);
2198 };
2199 }
2200 
2201 void removeDeadBindingsWorker::VisitAddedToCluster(const MemRegion *baseR,
2202  const ClusterBindings &C) {
2203 
2204  if (const VarRegion *VR = dyn_cast<VarRegion>(baseR)) {
2205  if (SymReaper.isLive(VR))
2206  AddToWorkList(baseR, &C);
2207 
2208  return;
2209  }
2210 
2211  if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(baseR)) {
2212  if (SymReaper.isLive(SR->getSymbol()))
2213  AddToWorkList(SR, &C);
2214  else
2215  Postponed.push_back(SR);
2216 
2217  return;
2218  }
2219 
2220  if (isa<NonStaticGlobalSpaceRegion>(baseR)) {
2221  AddToWorkList(baseR, &C);
2222  return;
2223  }
2224 
2225  // CXXThisRegion in the current or parent location context is live.
2226  if (const CXXThisRegion *TR = dyn_cast<CXXThisRegion>(baseR)) {
2227  const StackArgumentsSpaceRegion *StackReg =
2228  cast<StackArgumentsSpaceRegion>(TR->getSuperRegion());
2229  const StackFrameContext *RegCtx = StackReg->getStackFrame();
2230  if (CurrentLCtx &&
2231  (RegCtx == CurrentLCtx || RegCtx->isParentOf(CurrentLCtx)))
2232  AddToWorkList(TR, &C);
2233  }
2234 }
2235 
2236 void removeDeadBindingsWorker::VisitCluster(const MemRegion *baseR,
2237  const ClusterBindings *C) {
2238  if (!C)
2239  return;
2240 
2241  // Mark the symbol for any SymbolicRegion with live bindings as live itself.
2242  // This means we should continue to track that symbol.
2243  if (const SymbolicRegion *SymR = dyn_cast<SymbolicRegion>(baseR))
2244  SymReaper.markLive(SymR->getSymbol());
2245 
2246  for (ClusterBindings::iterator I = C->begin(), E = C->end(); I != E; ++I)
2247  VisitBinding(I.getData());
2248 }
2249 
2250 void removeDeadBindingsWorker::VisitBinding(SVal V) {
2251  // Is it a LazyCompoundVal? All referenced regions are live as well.
2254 
2255  const RegionStoreManager::SValListTy &Vals = RM.getInterestingValues(*LCS);
2256 
2257  for (RegionStoreManager::SValListTy::const_iterator I = Vals.begin(),
2258  E = Vals.end();
2259  I != E; ++I)
2260  VisitBinding(*I);
2261 
2262  return;
2263  }
2264 
2265  // If V is a region, then add it to the worklist.
2266  if (const MemRegion *R = V.getAsRegion()) {
2267  AddToWorkList(R);
2268 
2269  // All regions captured by a block are also live.
2270  if (const BlockDataRegion *BR = dyn_cast<BlockDataRegion>(R)) {
2271  BlockDataRegion::referenced_vars_iterator I = BR->referenced_vars_begin(),
2272  E = BR->referenced_vars_end();
2273  for ( ; I != E; ++I)
2274  AddToWorkList(I.getCapturedRegion());
2275  }
2276  }
2277 
2278 
2279  // Update the set of live symbols.
2280  for (SymExpr::symbol_iterator SI = V.symbol_begin(), SE = V.symbol_end();
2281  SI!=SE; ++SI)
2282  SymReaper.markLive(*SI);
2283 }
2284 
2285 bool removeDeadBindingsWorker::UpdatePostponed() {
2286  // See if any postponed SymbolicRegions are actually live now, after
2287  // having done a scan.
2288  bool changed = false;
2289 
2291  I = Postponed.begin(), E = Postponed.end() ; I != E ; ++I) {
2292  if (const SymbolicRegion *SR = *I) {
2293  if (SymReaper.isLive(SR->getSymbol())) {
2294  changed |= AddToWorkList(SR);
2295  *I = nullptr;
2296  }
2297  }
2298  }
2299 
2300  return changed;
2301 }
2302 
2303 StoreRef RegionStoreManager::removeDeadBindings(Store store,
2304  const StackFrameContext *LCtx,
2305  SymbolReaper& SymReaper) {
2306  RegionBindingsRef B = getRegionBindings(store);
2307  removeDeadBindingsWorker W(*this, StateMgr, B, SymReaper, LCtx);
2308  W.GenerateClusters();
2309 
2310  // Enqueue the region roots onto the worklist.
2311  for (SymbolReaper::region_iterator I = SymReaper.region_begin(),
2312  E = SymReaper.region_end(); I != E; ++I) {
2313  W.AddToWorkList(*I);
2314  }
2315 
2316  do W.RunWorkList(); while (W.UpdatePostponed());
2317 
2318  // We have now scanned the store, marking reachable regions and symbols
2319  // as live. We now remove all the regions that are dead from the store
2320  // as well as update DSymbols with the set symbols that are now dead.
2321  for (RegionBindingsRef::iterator I = B.begin(), E = B.end(); I != E; ++I) {
2322  const MemRegion *Base = I.getKey();
2323 
2324  // If the cluster has been visited, we know the region has been marked.
2325  if (W.isVisited(Base))
2326  continue;
2327 
2328  // Remove the dead entry.
2329  B = B.remove(Base);
2330 
2331  if (const SymbolicRegion *SymR = dyn_cast<SymbolicRegion>(Base))
2332  SymReaper.maybeDead(SymR->getSymbol());
2333 
2334  // Mark all non-live symbols that this binding references as dead.
2335  const ClusterBindings &Cluster = I.getData();
2336  for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end();
2337  CI != CE; ++CI) {
2338  SVal X = CI.getData();
2340  for (; SI != SE; ++SI)
2341  SymReaper.maybeDead(*SI);
2342  }
2343  }
2344 
2345  return StoreRef(B.asStore(), *this);
2346 }
2347 
2348 //===----------------------------------------------------------------------===//
2349 // Utility methods.
2350 //===----------------------------------------------------------------------===//
2351 
2352 void RegionStoreManager::print(Store store, raw_ostream &OS,
2353  const char* nl, const char *sep) {
2354  RegionBindingsRef B = getRegionBindings(store);
2355  OS << "Store (direct and default bindings), "
2356  << B.asStore()
2357  << " :" << nl;
2358  B.dump(OS, nl);
2359 }
TypedValueRegion - An abstract class representing regions having a typed value.
Definition: MemRegion.h:498
MemRegion - The root abstract class for all memory regions.
Definition: MemRegion.h:77
virtual DefinedOrUnknownSVal getExtent(SValBuilder &svalBuilder) const
getExtent - Returns the size of the region in bytes.
Definition: MemRegion.h:426
bool isInSystemHeader() const
Returns true if the callee is known to be from a system header.
Definition: CallEvent.h:209
static void getSymbolicOffsetFields(BindingKey K, FieldVector &Fields)
bool operator==(CanQual< T > x, CanQual< U > y)
Information about invalidation for a particular region/symbol.
Definition: MemRegion.h:1320
bool maybeDead(SymbolRef sym)
If a symbol is known to be live, marks the symbol as live.
virtual QualType getValueType() const =0
virtual bool isBoundable() const
Definition: MemRegion.h:188
static bool isRecordEmpty(const RecordDecl *RD)
bool isVoidPointerType() const
Definition: Type.cpp:384
const void * Store
Definition: StoreRef.h:26
const Expr * getInit() const
Definition: Decl.h:1068
static Optional< nonloc::LazyCompoundVal > getExistingLazyBinding(SValBuilder &SVB, RegionBindingsConstRef B, const SubRegion *R, bool AllowSubregionBindings)
Value representing integer constant.
Definition: SVals.h:339
QualType getElementType() const
Definition: MemRegion.h:1033
const MemRegion * getBaseRegion() const
Definition: MemRegion.cpp:1063
bool isZeroConstant() const
Definition: SVals.cpp:186
bool isUnionType() const
Definition: Type.cpp:390
std::unique_ptr< StoreManager > CreateFieldsOnlyRegionStoreManager(ProgramStateManager &StMgr)
Symbolic value. These values used to capture symbolic execution of the program.
Definition: SymbolManager.h:42
llvm::ImmutableMap< BindingKey, SVal > ClusterBindings
const MemSpaceRegion * getMemorySpace() const
Definition: MemRegion.cpp:1031
bool isScalarType() const
Definition: Type.h:5461
SmallVector< const FieldDecl *, 8 > FieldVector
bool hasAttr() const
Definition: DeclBase.h:487
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:89
const ASTMatchFinder::BindKind Bind
bool isReferenceType() const
Definition: Type.h:5241
bool isStructureOrClassType() const
Definition: Type.cpp:377
bool isAnyPointerType() const
Definition: Type.h:5235
const MemRegion * getRegion() const
Definition: MemRegion.h:1001
static bool canSymbolicate(QualType T)
bool hasSameUnqualifiedType(QualType T1, QualType T2) const
Determine whether the given types are equivalent after cvr-qualifiers have been removed.
Definition: ASTContext.h:1896
const VarDecl * getDecl() const
Definition: MemRegion.h:877
RegionRawOffset getAsArrayOffset() const
Compute the offset within the array. The array might also be a subobject.
Definition: MemRegion.cpp:1122
static bool isLocType(QualType T)
Definition: SVals.h:291
uint32_t getCodeUnit(size_t i) const
Definition: Expr.h:1543
unsigned getLength() const
Definition: Expr.h:1554
static void dump(llvm::raw_ostream &OS, StringRef FunctionName, ArrayRef< CounterExpression > Expressions, ArrayRef< CounterMappingRegion > Regions)
field_range fields() const
Definition: Decl.h:3349
SymbolRef getSymbol() const
Definition: MemRegion.h:719
bool isUnknownOrUndef() const
Definition: SVals.h:125
llvm::ImmutableMap< const MemRegion *, ClusterBindings > RegionBindings
SymExpr::symbol_iterator symbol_begin() const
Definition: SVals.h:177
QualType getValueType() const override
Definition: MemRegion.h:881
bool isConstant() const
Definition: SVals.cpp:174
Represent a region's offset within the top level base region.
Definition: MemRegion.h:45
QualType getType() const
Definition: Decl.h:538
virtual QualType getType() const =0
const MemRegion * getSuperRegion() const
Definition: MemRegion.h:421
AnnotatingParser & P
std::unique_ptr< StoreManager > CreateRegionStoreManager(ProgramStateManager &StMgr)
bool isUnion() const
Definition: Decl.h:2906
const StackFrameContext * getStackFrame() const
Definition: MemRegion.h:371
llvm::ImmutableList< SVal >::iterator iterator
Definition: SVals.h:420
static bool isCompatibleWithFields(BindingKey K, const FieldVector &Fields)
ID
Defines the set of possible language-specific address spaces.
Definition: AddressSpaces.h:27
QualType getPointeeType() const
Definition: Type.cpp:414
static void collectSubRegionBindings(SmallVectorImpl< BindingPair > &Bindings, SValBuilder &SVB, const ClusterBindings &Cluster, const SubRegion *Top, BindingKey TopKey, bool IncludeAllDefaultBindings)
GlobalsFilterKind
bool hasSymbolicOffset() const
Definition: MemRegion.h:62
Optional< T > getAs() const
Convert to the specified SVal type, returning None if this SVal is not of the desired type...
Definition: SVals.h:86
static CharUnits fromQuantity(QuantityType Quantity)
fromQuantity - Construct a CharUnits quantity from a raw integer type.
Definition: CharUnits.h:63
RegionSetTy::const_iterator region_iterator
The result type of a method or function.
RecordDecl * getDefinition() const
Definition: Decl.h:3339
const LazyCompoundValData * getCVData() const
Definition: SVals.h:442
llvm::ImmutableMapRef< BindingKey, SVal > ClusterBindingsRef
const MatchFinder::MatchFinderOptions & Options
bool scan(nonloc::LazyCompoundVal val)
#define false
Definition: stdbool.h:33
Kind
bool isIntegralOrEnumerationType() const
Determine whether this type is an integral or enumeration type.
Definition: Type.h:5476
region_iterator region_begin() const
static QualType getUnderlyingType(const SubRegion *R)
const FieldDecl * getDecl() const
Definition: MemRegion.h:934
bool isSubRegionOf(const MemRegion *R) const override
Check if the region is a subregion of the given region.
Definition: MemRegion.cpp:149
ASTContext & getContext()
Definition: SValBuilder.h:121
SymExpr::symbol_iterator symbol_end() const
Definition: SVals.h:185
A class responsible for cleaning up unused symbols.
bool isUndef() const
Definition: SVals.h:121
const T * castAs() const
Definition: Type.h:5586
QualType getLocationType() const override
Definition: MemRegion.h:507
bool isVectorType() const
Definition: Type.h:5298
bool operator<(DeclarationName LHS, DeclarationName RHS)
Tells that a region's contents is not changed.
Definition: MemRegion.h:1334
NonLoc getIndex() const
Definition: MemRegion.h:1027
RegionOffset getAsOffset() const
Compute the offset within the top level memory object.
Definition: MemRegion.cpp:1179
static const Type * getElementType(const Expr *BaseExpr)
raw_ostream & operator<<(raw_ostream &Out, const CheckerBase &Checker)
Dump checker name to stream.
Definition: Checker.cpp:34
std::unique_ptr< DiagnosticConsumer > create(StringRef OutputFile, DiagnosticOptions *Diags, bool MergeChildRecords=false)
Returns a DiagnosticConsumer that serializes diagnostics to a bitcode file.
Represents symbolic expression.
Definition: SVals.h:313
const MemRegion * getAsRegion() const
Definition: SVals.cpp:135
Represents an abstract call to a function or method along a particular path.
Definition: CallEvent.h:113
bool field_empty() const
Definition: Decl.h:3358
region_iterator region_end() const
const T * getAs() const
Definition: Type.h:5555
bool isUnknown() const
Definition: SVals.h:117
int64_t getOffset() const
Definition: MemRegion.h:64
const TypedValueRegion * getRegion() const
Definition: SVals.cpp:154
uint64_t getCharWidth() const
Return the size of the character type, in bits.
Definition: ASTContext.h:1705
std::pair< BindingKey, SVal > BindingPair
__PTRDIFF_TYPE__ ptrdiff_t
Definition: stddef.h:51
X
Definition: SemaDecl.cpp:11429
static bool isUnionField(const FieldRegion *FR)
Represents a C++ struct/union/class.
Definition: DeclCXX.h:285
SymbolRef getAsSymbol(bool IncludeBaseRegions=false) const
If this SVal wraps a symbol return that SymbolRef. Otherwise, return 0.
Definition: SVals.cpp:111
bool isArrayType() const
Definition: Type.h:5271
Defines the clang::TargetInfo interface.
StringRegion - Region associated with a StringLiteral.
Definition: MemRegion.h:741
ElementRegin is used to represent both array elements and casts.
Definition: MemRegion.h:1008
QualType getValueType() const override
Definition: MemRegion.h:936
const MemRegion * getRegion() const
Definition: MemRegion.h:60
virtual bool isSubRegionOf(const MemRegion *R) const
Check if the region is a subregion of the given region.
Definition: MemRegion.cpp:1081
QualType getElementType() const
Definition: Type.h:2434
int getOptionAsInteger(StringRef Name, int DefaultVal, const ento::CheckerBase *C=nullptr, bool SearchInParents=false)
const RegionBindingsRef & RegionBindingsConstRef
iterator begin() const
Definition: SVals.cpp:162
#define true
Definition: stdbool.h:32
bool hasStackNonParametersStorage() const
Definition: MemRegion.cpp:1047
bool isConstQualified() const
Determine whether this type is const-qualified.
Definition: Type.h:5075
bool isNull() const
isNull - Return true if this QualType doesn't point to a type yet.
Definition: Type.h:633
T castAs() const
Convert to the specified SVal type, asserting that this SVal is of the desired type.
Definition: SVals.h:75
TypedRegion - An abstract class representing regions that are typed.
Definition: MemRegion.h:476
bool hasLocalStorage() const
Definition: Decl.h:887
const RecordDecl * getParent() const
Definition: Decl.h:2424
Iterator over symbols that the current symbol depends on.
Definition: SymbolManager.h:76
const void * getStore() const
Definition: SVals.cpp:150