1 //== RegionStore.cpp - Field-sensitive store model --------------*- C++ -*--==//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
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.
16 //===----------------------------------------------------------------------===//
18 #include "clang/AST/Attr.h"
19 #include "clang/AST/CharUnits.h"
20 #include "clang/Analysis/Analyses/LiveVariables.h"
21 #include "clang/Analysis/AnalysisContext.h"
22 #include "clang/Basic/TargetInfo.h"
23 #include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
24 #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
25 #include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h"
26 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
27 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h"
28 #include "clang/StaticAnalyzer/Core/PathSensitive/SubEngine.h"
29 #include "llvm/ADT/ImmutableMap.h"
30 #include "llvm/ADT/Optional.h"
31 #include "llvm/Support/raw_ostream.h"
34 using namespace clang;
37 //===----------------------------------------------------------------------===//
38 // Representation of binding keys.
39 //===----------------------------------------------------------------------===//
44 enum Kind { Default = 0x0, Direct = 0x1 };
46 enum { Symbolic = 0x2 };
48 llvm::PointerIntPair<const MemRegion *, 2> P;
51 /// Create a key for a binding to region \p r, which has a symbolic offset
52 /// from region \p Base.
53 explicit BindingKey(const SubRegion *r, const SubRegion *Base, Kind k)
54 : P(r, k | Symbolic), Data(reinterpret_cast<uintptr_t>(Base)) {
55 assert(r && Base && "Must have known regions.");
56 assert(getConcreteOffsetRegion() == Base && "Failed to store base region");
59 /// Create a key for a binding at \p offset from base region \p r.
60 explicit BindingKey(const MemRegion *r, uint64_t offset, Kind k)
61 : P(r, k), Data(offset) {
62 assert(r && "Must have known regions.");
63 assert(getOffset() == offset && "Failed to store offset");
64 assert((r == r->getBaseRegion() || isa<ObjCIvarRegion>(r)) && "Not a base");
68 bool isDirect() const { return P.getInt() & Direct; }
69 bool hasSymbolicOffset() const { return P.getInt() & Symbolic; }
71 const MemRegion *getRegion() const { return P.getPointer(); }
72 uint64_t getOffset() const {
73 assert(!hasSymbolicOffset());
77 const SubRegion *getConcreteOffsetRegion() const {
78 assert(hasSymbolicOffset());
79 return reinterpret_cast<const SubRegion *>(static_cast<uintptr_t>(Data));
82 const MemRegion *getBaseRegion() const {
83 if (hasSymbolicOffset())
84 return getConcreteOffsetRegion()->getBaseRegion();
85 return getRegion()->getBaseRegion();
88 void Profile(llvm::FoldingSetNodeID& ID) const {
89 ID.AddPointer(P.getOpaqueValue());
93 static BindingKey Make(const MemRegion *R, Kind k);
95 bool operator<(const BindingKey &X) const {
96 if (P.getOpaqueValue() < X.P.getOpaqueValue())
98 if (P.getOpaqueValue() > X.P.getOpaqueValue())
100 return Data < X.Data;
103 bool operator==(const BindingKey &X) const {
104 return P.getOpaqueValue() == X.P.getOpaqueValue() &&
110 } // end anonymous namespace
112 BindingKey BindingKey::Make(const MemRegion *R, Kind k) {
113 const RegionOffset &RO = R->getAsOffset();
114 if (RO.hasSymbolicOffset())
115 return BindingKey(cast<SubRegion>(R), cast<SubRegion>(RO.getRegion()), k);
117 return BindingKey(RO.getRegion(), RO.getOffset(), k);
122 raw_ostream &operator<<(raw_ostream &os, BindingKey K) {
123 os << '(' << K.getRegion();
124 if (!K.hasSymbolicOffset())
125 os << ',' << K.getOffset();
126 os << ',' << (K.isDirect() ? "direct" : "default")
131 template <typename T> struct isPodLike;
132 template <> struct isPodLike<BindingKey> {
133 static const bool value = true;
135 } // end llvm namespace
137 LLVM_DUMP_METHOD void BindingKey::dump() const { llvm::errs() << *this; }
139 //===----------------------------------------------------------------------===//
140 // Actual Store type.
141 //===----------------------------------------------------------------------===//
143 typedef llvm::ImmutableMap<BindingKey, SVal> ClusterBindings;
144 typedef llvm::ImmutableMapRef<BindingKey, SVal> ClusterBindingsRef;
145 typedef std::pair<BindingKey, SVal> BindingPair;
147 typedef llvm::ImmutableMap<const MemRegion *, ClusterBindings>
151 class RegionBindingsRef : public llvm::ImmutableMapRef<const MemRegion *,
153 ClusterBindings::Factory *CBFactory;
156 typedef llvm::ImmutableMapRef<const MemRegion *, ClusterBindings>
159 RegionBindingsRef(ClusterBindings::Factory &CBFactory,
160 const RegionBindings::TreeTy *T,
161 RegionBindings::TreeTy::Factory *F)
162 : llvm::ImmutableMapRef<const MemRegion *, ClusterBindings>(T, F),
163 CBFactory(&CBFactory) {}
165 RegionBindingsRef(const ParentTy &P, ClusterBindings::Factory &CBFactory)
166 : llvm::ImmutableMapRef<const MemRegion *, ClusterBindings>(P),
167 CBFactory(&CBFactory) {}
169 RegionBindingsRef add(key_type_ref K, data_type_ref D) const {
170 return RegionBindingsRef(static_cast<const ParentTy *>(this)->add(K, D),
174 RegionBindingsRef remove(key_type_ref K) const {
175 return RegionBindingsRef(static_cast<const ParentTy *>(this)->remove(K),
179 RegionBindingsRef addBinding(BindingKey K, SVal V) const;
181 RegionBindingsRef addBinding(const MemRegion *R,
182 BindingKey::Kind k, SVal V) const;
184 const SVal *lookup(BindingKey K) const;
185 const SVal *lookup(const MemRegion *R, BindingKey::Kind k) const;
186 using llvm::ImmutableMapRef<const MemRegion *, ClusterBindings>::lookup;
188 RegionBindingsRef removeBinding(BindingKey K);
190 RegionBindingsRef removeBinding(const MemRegion *R,
193 RegionBindingsRef removeBinding(const MemRegion *R) {
194 return removeBinding(R, BindingKey::Direct).
195 removeBinding(R, BindingKey::Default);
198 Optional<SVal> getDirectBinding(const MemRegion *R) const;
200 /// getDefaultBinding - Returns an SVal* representing an optional default
201 /// binding associated with a region and its subregions.
202 Optional<SVal> getDefaultBinding(const MemRegion *R) const;
204 /// Return the internal tree as a Store.
205 Store asStore() const {
206 return asImmutableMap().getRootWithoutRetain();
209 void dump(raw_ostream &OS, const char *nl) const {
210 for (iterator I = begin(), E = end(); I != E; ++I) {
211 const ClusterBindings &Cluster = I.getData();
212 for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end();
214 OS << ' ' << CI.getKey() << " : " << CI.getData() << nl;
220 LLVM_DUMP_METHOD void dump() const { dump(llvm::errs(), "\n"); }
222 } // end anonymous namespace
224 typedef const RegionBindingsRef& RegionBindingsConstRef;
226 Optional<SVal> RegionBindingsRef::getDirectBinding(const MemRegion *R) const {
227 return Optional<SVal>::create(lookup(R, BindingKey::Direct));
230 Optional<SVal> RegionBindingsRef::getDefaultBinding(const MemRegion *R) const {
231 if (R->isBoundable())
232 if (const TypedValueRegion *TR = dyn_cast<TypedValueRegion>(R))
233 if (TR->getValueType()->isUnionType())
236 return Optional<SVal>::create(lookup(R, BindingKey::Default));
239 RegionBindingsRef RegionBindingsRef::addBinding(BindingKey K, SVal V) const {
240 const MemRegion *Base = K.getBaseRegion();
242 const ClusterBindings *ExistingCluster = lookup(Base);
243 ClusterBindings Cluster =
244 (ExistingCluster ? *ExistingCluster : CBFactory->getEmptyMap());
246 ClusterBindings NewCluster = CBFactory->add(Cluster, K, V);
247 return add(Base, NewCluster);
251 RegionBindingsRef RegionBindingsRef::addBinding(const MemRegion *R,
254 return addBinding(BindingKey::Make(R, k), V);
257 const SVal *RegionBindingsRef::lookup(BindingKey K) const {
258 const ClusterBindings *Cluster = lookup(K.getBaseRegion());
261 return Cluster->lookup(K);
264 const SVal *RegionBindingsRef::lookup(const MemRegion *R,
265 BindingKey::Kind k) const {
266 return lookup(BindingKey::Make(R, k));
269 RegionBindingsRef RegionBindingsRef::removeBinding(BindingKey K) {
270 const MemRegion *Base = K.getBaseRegion();
271 const ClusterBindings *Cluster = lookup(Base);
275 ClusterBindings NewCluster = CBFactory->remove(*Cluster, K);
276 if (NewCluster.isEmpty())
278 return add(Base, NewCluster);
281 RegionBindingsRef RegionBindingsRef::removeBinding(const MemRegion *R,
283 return removeBinding(BindingKey::Make(R, k));
286 //===----------------------------------------------------------------------===//
287 // Fine-grained control of RegionStoreManager.
288 //===----------------------------------------------------------------------===//
291 struct minimal_features_tag {};
292 struct maximal_features_tag {};
294 class RegionStoreFeatures {
297 RegionStoreFeatures(minimal_features_tag) :
298 SupportsFields(false) {}
300 RegionStoreFeatures(maximal_features_tag) :
301 SupportsFields(true) {}
303 void enableFields(bool t) { SupportsFields = t; }
305 bool supportsFields() const { return SupportsFields; }
309 //===----------------------------------------------------------------------===//
310 // Main RegionStore logic.
311 //===----------------------------------------------------------------------===//
314 class invalidateRegionsWorker;
316 class RegionStoreManager : public StoreManager {
318 const RegionStoreFeatures Features;
320 RegionBindings::Factory RBFactory;
321 mutable ClusterBindings::Factory CBFactory;
323 typedef std::vector<SVal> SValListTy;
325 typedef llvm::DenseMap<const LazyCompoundValData *,
326 SValListTy> LazyBindingsMapTy;
327 LazyBindingsMapTy LazyBindingsMap;
329 /// The largest number of fields a struct can have and still be
330 /// considered "small".
332 /// This is currently used to decide whether or not it is worth "forcing" a
333 /// LazyCompoundVal on bind.
335 /// This is controlled by 'region-store-small-struct-limit' option.
336 /// To disable all small-struct-dependent behavior, set the option to "0".
337 unsigned SmallStructLimit;
339 /// \brief A helper used to populate the work list with the given set of
341 void populateWorkList(invalidateRegionsWorker &W,
342 ArrayRef<SVal> Values,
343 InvalidatedRegions *TopLevelRegions);
346 RegionStoreManager(ProgramStateManager& mgr, const RegionStoreFeatures &f)
347 : StoreManager(mgr), Features(f),
348 RBFactory(mgr.getAllocator()), CBFactory(mgr.getAllocator()),
349 SmallStructLimit(0) {
350 if (SubEngine *Eng = StateMgr.getOwningEngine()) {
351 AnalyzerOptions &Options = Eng->getAnalysisManager().options;
353 Options.getOptionAsInteger("region-store-small-struct-limit", 2);
358 /// setImplicitDefaultValue - Set the default binding for the provided
359 /// MemRegion to the value implicitly defined for compound literals when
360 /// the value is not specified.
361 RegionBindingsRef setImplicitDefaultValue(RegionBindingsConstRef B,
362 const MemRegion *R, QualType T);
364 /// ArrayToPointer - Emulates the "decay" of an array to a pointer
365 /// type. 'Array' represents the lvalue of the array being decayed
366 /// to a pointer, and the returned SVal represents the decayed
367 /// version of that lvalue (i.e., a pointer to the first element of
368 /// the array). This is called by ExprEngine when evaluating
369 /// casts from arrays to pointers.
370 SVal ArrayToPointer(Loc Array, QualType ElementTy) override;
372 StoreRef getInitialStore(const LocationContext *InitLoc) override {
373 return StoreRef(RBFactory.getEmptyMap().getRootWithoutRetain(), *this);
376 //===-------------------------------------------------------------------===//
377 // Binding values to regions.
378 //===-------------------------------------------------------------------===//
379 RegionBindingsRef invalidateGlobalRegion(MemRegion::Kind K,
382 const LocationContext *LCtx,
384 InvalidatedRegions *Invalidated);
386 StoreRef invalidateRegions(Store store,
387 ArrayRef<SVal> Values,
388 const Expr *E, unsigned Count,
389 const LocationContext *LCtx,
390 const CallEvent *Call,
391 InvalidatedSymbols &IS,
392 RegionAndSymbolInvalidationTraits &ITraits,
393 InvalidatedRegions *Invalidated,
394 InvalidatedRegions *InvalidatedTopLevel) override;
396 bool scanReachableSymbols(Store S, const MemRegion *R,
397 ScanReachableSymbols &Callbacks) override;
399 RegionBindingsRef removeSubRegionBindings(RegionBindingsConstRef B,
402 public: // Part of public interface to class.
404 StoreRef Bind(Store store, Loc LV, SVal V) override {
405 return StoreRef(bind(getRegionBindings(store), LV, V).asStore(), *this);
408 RegionBindingsRef bind(RegionBindingsConstRef B, Loc LV, SVal V);
410 // BindDefault is only used to initialize a region with a default value.
411 StoreRef BindDefault(Store store, const MemRegion *R, SVal V) override {
412 RegionBindingsRef B = getRegionBindings(store);
413 assert(!B.lookup(R, BindingKey::Direct));
415 BindingKey Key = BindingKey::Make(R, BindingKey::Default);
417 const SubRegion *SR = cast<SubRegion>(R);
418 assert(SR->getAsOffset().getOffset() ==
419 SR->getSuperRegion()->getAsOffset().getOffset() &&
420 "A default value must come from a super-region");
421 B = removeSubRegionBindings(B, SR);
423 B = B.addBinding(Key, V);
426 return StoreRef(B.asImmutableMap().getRootWithoutRetain(), *this);
429 /// Attempt to extract the fields of \p LCV and bind them to the struct region
432 /// This path is used when it seems advantageous to "force" loading the values
433 /// within a LazyCompoundVal to bind memberwise to the struct region, rather
434 /// than using a Default binding at the base of the entire region. This is a
435 /// heuristic attempting to avoid building long chains of LazyCompoundVals.
437 /// \returns The updated store bindings, or \c None if binding non-lazily
438 /// would be too expensive.
439 Optional<RegionBindingsRef> tryBindSmallStruct(RegionBindingsConstRef B,
440 const TypedValueRegion *R,
441 const RecordDecl *RD,
442 nonloc::LazyCompoundVal LCV);
444 /// BindStruct - Bind a compound value to a structure.
445 RegionBindingsRef bindStruct(RegionBindingsConstRef B,
446 const TypedValueRegion* R, SVal V);
448 /// BindVector - Bind a compound value to a vector.
449 RegionBindingsRef bindVector(RegionBindingsConstRef B,
450 const TypedValueRegion* R, SVal V);
452 RegionBindingsRef bindArray(RegionBindingsConstRef B,
453 const TypedValueRegion* R,
456 /// Clears out all bindings in the given region and assigns a new value
457 /// as a Default binding.
458 RegionBindingsRef bindAggregate(RegionBindingsConstRef B,
459 const TypedRegion *R,
462 /// \brief Create a new store with the specified binding removed.
463 /// \param ST the original store, that is the basis for the new store.
464 /// \param L the location whose binding should be removed.
465 StoreRef killBinding(Store ST, Loc L) override;
467 void incrementReferenceCount(Store store) override {
468 getRegionBindings(store).manualRetain();
471 /// If the StoreManager supports it, decrement the reference count of
472 /// the specified Store object. If the reference count hits 0, the memory
473 /// associated with the object is recycled.
474 void decrementReferenceCount(Store store) override {
475 getRegionBindings(store).manualRelease();
478 bool includedInBindings(Store store, const MemRegion *region) const override;
480 /// \brief Return the value bound to specified location in a given state.
482 /// The high level logic for this method is this:
485 /// return L's binding
486 /// else if L is in killset
489 /// if L is on stack or heap
493 SVal getBinding(Store S, Loc L, QualType T) override {
494 return getBinding(getRegionBindings(S), L, T);
497 SVal getBinding(RegionBindingsConstRef B, Loc L, QualType T = QualType());
499 SVal getBindingForElement(RegionBindingsConstRef B, const ElementRegion *R);
501 SVal getBindingForField(RegionBindingsConstRef B, const FieldRegion *R);
503 SVal getBindingForObjCIvar(RegionBindingsConstRef B, const ObjCIvarRegion *R);
505 SVal getBindingForVar(RegionBindingsConstRef B, const VarRegion *R);
507 SVal getBindingForLazySymbol(const TypedValueRegion *R);
509 SVal getBindingForFieldOrElementCommon(RegionBindingsConstRef B,
510 const TypedValueRegion *R,
513 SVal getLazyBinding(const SubRegion *LazyBindingRegion,
514 RegionBindingsRef LazyBinding);
516 /// Get bindings for the values in a struct and return a CompoundVal, used
517 /// when doing struct copy:
520 /// y's value is retrieved by this method.
521 SVal getBindingForStruct(RegionBindingsConstRef B, const TypedValueRegion *R);
522 SVal getBindingForArray(RegionBindingsConstRef B, const TypedValueRegion *R);
523 NonLoc createLazyBinding(RegionBindingsConstRef B, const TypedValueRegion *R);
525 /// Used to lazily generate derived symbols for bindings that are defined
526 /// implicitly by default bindings in a super region.
528 /// Note that callers may need to specially handle LazyCompoundVals, which
529 /// are returned as is in case the caller needs to treat them differently.
530 Optional<SVal> getBindingForDerivedDefaultValue(RegionBindingsConstRef B,
531 const MemRegion *superR,
532 const TypedValueRegion *R,
535 /// Get the state and region whose binding this region \p R corresponds to.
537 /// If there is no lazy binding for \p R, the returned value will have a null
538 /// \c second. Note that a null pointer can represents a valid Store.
539 std::pair<Store, const SubRegion *>
540 findLazyBinding(RegionBindingsConstRef B, const SubRegion *R,
541 const SubRegion *originalRegion);
543 /// Returns the cached set of interesting SVals contained within a lazy
546 /// The precise value of "interesting" is determined for the purposes of
547 /// RegionStore's internal analysis. It must always contain all regions and
548 /// symbols, but may omit constants and other kinds of SVal.
549 const SValListTy &getInterestingValues(nonloc::LazyCompoundVal LCV);
551 //===------------------------------------------------------------------===//
553 //===------------------------------------------------------------------===//
555 /// removeDeadBindings - Scans the RegionStore of 'state' for dead values.
556 /// It returns a new Store with these values removed.
557 StoreRef removeDeadBindings(Store store, const StackFrameContext *LCtx,
558 SymbolReaper& SymReaper) override;
560 //===------------------------------------------------------------------===//
562 //===------------------------------------------------------------------===//
564 // FIXME: This method will soon be eliminated; see the note in Store.h.
565 DefinedOrUnknownSVal getSizeInElements(ProgramStateRef state,
567 QualType EleTy) override;
569 //===------------------------------------------------------------------===//
571 //===------------------------------------------------------------------===//
573 RegionBindingsRef getRegionBindings(Store store) const {
574 return RegionBindingsRef(CBFactory,
575 static_cast<const RegionBindings::TreeTy*>(store),
576 RBFactory.getTreeFactory());
579 void print(Store store, raw_ostream &Out, const char* nl,
580 const char *sep) override;
582 void iterBindings(Store store, BindingsHandler& f) override {
583 RegionBindingsRef B = getRegionBindings(store);
584 for (RegionBindingsRef::iterator I = B.begin(), E = B.end(); I != E; ++I) {
585 const ClusterBindings &Cluster = I.getData();
586 for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end();
588 const BindingKey &K = CI.getKey();
591 if (const SubRegion *R = dyn_cast<SubRegion>(K.getRegion())) {
592 // FIXME: Possibly incorporate the offset?
593 if (!f.HandleBinding(*this, store, R, CI.getData()))
601 } // end anonymous namespace
603 //===----------------------------------------------------------------------===//
604 // RegionStore creation.
605 //===----------------------------------------------------------------------===//
607 std::unique_ptr<StoreManager>
608 ento::CreateRegionStoreManager(ProgramStateManager &StMgr) {
609 RegionStoreFeatures F = maximal_features_tag();
610 return llvm::make_unique<RegionStoreManager>(StMgr, F);
613 std::unique_ptr<StoreManager>
614 ento::CreateFieldsOnlyRegionStoreManager(ProgramStateManager &StMgr) {
615 RegionStoreFeatures F = minimal_features_tag();
616 F.enableFields(true);
617 return llvm::make_unique<RegionStoreManager>(StMgr, F);
621 //===----------------------------------------------------------------------===//
622 // Region Cluster analysis.
623 //===----------------------------------------------------------------------===//
626 /// Used to determine which global regions are automatically included in the
627 /// initial worklist of a ClusterAnalysis.
628 enum GlobalsFilterKind {
629 /// Don't include any global regions.
631 /// Only include system globals.
633 /// Include all global regions.
637 template <typename DERIVED>
638 class ClusterAnalysis {
640 typedef llvm::DenseMap<const MemRegion *, const ClusterBindings *> ClusterMap;
641 typedef const MemRegion * WorkListElement;
642 typedef SmallVector<WorkListElement, 10> WorkList;
644 llvm::SmallPtrSet<const ClusterBindings *, 16> Visited;
648 RegionStoreManager &RM;
650 SValBuilder &svalBuilder;
656 const ClusterBindings *getCluster(const MemRegion *R) {
660 /// Returns true if all clusters in the given memspace should be initially
661 /// included in the cluster analysis. Subclasses may provide their
662 /// own implementation.
663 bool includeEntireMemorySpace(const MemRegion *Base) {
668 ClusterAnalysis(RegionStoreManager &rm, ProgramStateManager &StateMgr,
670 : RM(rm), Ctx(StateMgr.getContext()),
671 svalBuilder(StateMgr.getSValBuilder()), B(std::move(b)) {}
673 RegionBindingsRef getRegionBindings() const { return B; }
675 bool isVisited(const MemRegion *R) {
676 return Visited.count(getCluster(R));
679 void GenerateClusters() {
680 // Scan the entire set of bindings and record the region clusters.
681 for (RegionBindingsRef::iterator RI = B.begin(), RE = B.end();
683 const MemRegion *Base = RI.getKey();
685 const ClusterBindings &Cluster = RI.getData();
686 assert(!Cluster.isEmpty() && "Empty clusters should be removed");
687 static_cast<DERIVED*>(this)->VisitAddedToCluster(Base, Cluster);
689 // If the base's memspace should be entirely invalidated, add the cluster
690 // to the workspace up front.
691 if (static_cast<DERIVED*>(this)->includeEntireMemorySpace(Base))
692 AddToWorkList(WorkListElement(Base), &Cluster);
696 bool AddToWorkList(WorkListElement E, const ClusterBindings *C) {
697 if (C && !Visited.insert(C).second)
703 bool AddToWorkList(const MemRegion *R) {
704 return static_cast<DERIVED*>(this)->AddToWorkList(R);
708 while (!WL.empty()) {
709 WorkListElement E = WL.pop_back_val();
710 const MemRegion *BaseR = E;
712 static_cast<DERIVED*>(this)->VisitCluster(BaseR, getCluster(BaseR));
716 void VisitAddedToCluster(const MemRegion *baseR, const ClusterBindings &C) {}
717 void VisitCluster(const MemRegion *baseR, const ClusterBindings *C) {}
719 void VisitCluster(const MemRegion *BaseR, const ClusterBindings *C,
721 static_cast<DERIVED*>(this)->VisitCluster(BaseR, C);
726 //===----------------------------------------------------------------------===//
727 // Binding invalidation.
728 //===----------------------------------------------------------------------===//
730 bool RegionStoreManager::scanReachableSymbols(Store S, const MemRegion *R,
731 ScanReachableSymbols &Callbacks) {
732 assert(R == R->getBaseRegion() && "Should only be called for base regions");
733 RegionBindingsRef B = getRegionBindings(S);
734 const ClusterBindings *Cluster = B.lookup(R);
739 for (ClusterBindings::iterator RI = Cluster->begin(), RE = Cluster->end();
741 if (!Callbacks.scan(RI.getData()))
748 static inline bool isUnionField(const FieldRegion *FR) {
749 return FR->getDecl()->getParent()->isUnion();
752 typedef SmallVector<const FieldDecl *, 8> FieldVector;
754 static void getSymbolicOffsetFields(BindingKey K, FieldVector &Fields) {
755 assert(K.hasSymbolicOffset() && "Not implemented for concrete offset keys");
757 const MemRegion *Base = K.getConcreteOffsetRegion();
758 const MemRegion *R = K.getRegion();
761 if (const FieldRegion *FR = dyn_cast<FieldRegion>(R))
762 if (!isUnionField(FR))
763 Fields.push_back(FR->getDecl());
765 R = cast<SubRegion>(R)->getSuperRegion();
769 static bool isCompatibleWithFields(BindingKey K, const FieldVector &Fields) {
770 assert(K.hasSymbolicOffset() && "Not implemented for concrete offset keys");
775 FieldVector FieldsInBindingKey;
776 getSymbolicOffsetFields(K, FieldsInBindingKey);
778 ptrdiff_t Delta = FieldsInBindingKey.size() - Fields.size();
780 return std::equal(FieldsInBindingKey.begin() + Delta,
781 FieldsInBindingKey.end(),
784 return std::equal(FieldsInBindingKey.begin(), FieldsInBindingKey.end(),
785 Fields.begin() - Delta);
788 /// Collects all bindings in \p Cluster that may refer to bindings within
791 /// Each binding is a pair whose \c first is the key (a BindingKey) and whose
792 /// \c second is the value (an SVal).
794 /// The \p IncludeAllDefaultBindings parameter specifies whether to include
795 /// default bindings that may extend beyond \p Top itself, e.g. if \p Top is
796 /// an aggregate within a larger aggregate with a default binding.
798 collectSubRegionBindings(SmallVectorImpl<BindingPair> &Bindings,
799 SValBuilder &SVB, const ClusterBindings &Cluster,
800 const SubRegion *Top, BindingKey TopKey,
801 bool IncludeAllDefaultBindings) {
802 FieldVector FieldsInSymbolicSubregions;
803 if (TopKey.hasSymbolicOffset()) {
804 getSymbolicOffsetFields(TopKey, FieldsInSymbolicSubregions);
805 Top = cast<SubRegion>(TopKey.getConcreteOffsetRegion());
806 TopKey = BindingKey::Make(Top, BindingKey::Default);
809 // Find the length (in bits) of the region being invalidated.
810 uint64_t Length = UINT64_MAX;
811 SVal Extent = Top->getExtent(SVB);
812 if (Optional<nonloc::ConcreteInt> ExtentCI =
813 Extent.getAs<nonloc::ConcreteInt>()) {
814 const llvm::APSInt &ExtentInt = ExtentCI->getValue();
815 assert(ExtentInt.isNonNegative() || ExtentInt.isUnsigned());
816 // Extents are in bytes but region offsets are in bits. Be careful!
817 Length = ExtentInt.getLimitedValue() * SVB.getContext().getCharWidth();
818 } else if (const FieldRegion *FR = dyn_cast<FieldRegion>(Top)) {
819 if (FR->getDecl()->isBitField())
820 Length = FR->getDecl()->getBitWidthValue(SVB.getContext());
823 for (ClusterBindings::iterator I = Cluster.begin(), E = Cluster.end();
825 BindingKey NextKey = I.getKey();
826 if (NextKey.getRegion() == TopKey.getRegion()) {
827 // FIXME: This doesn't catch the case where we're really invalidating a
828 // region with a symbolic offset. Example:
832 if (NextKey.getOffset() > TopKey.getOffset() &&
833 NextKey.getOffset() - TopKey.getOffset() < Length) {
834 // Case 1: The next binding is inside the region we're invalidating.
836 Bindings.push_back(*I);
838 } else if (NextKey.getOffset() == TopKey.getOffset()) {
839 // Case 2: The next binding is at the same offset as the region we're
840 // invalidating. In this case, we need to leave default bindings alone,
841 // since they may be providing a default value for a regions beyond what
842 // we're invalidating.
843 // FIXME: This is probably incorrect; consider invalidating an outer
844 // struct whose first field is bound to a LazyCompoundVal.
845 if (IncludeAllDefaultBindings || NextKey.isDirect())
846 Bindings.push_back(*I);
849 } else if (NextKey.hasSymbolicOffset()) {
850 const MemRegion *Base = NextKey.getConcreteOffsetRegion();
851 if (Top->isSubRegionOf(Base)) {
852 // Case 3: The next key is symbolic and we just changed something within
853 // its concrete region. We don't know if the binding is still valid, so
854 // we'll be conservative and include it.
855 if (IncludeAllDefaultBindings || NextKey.isDirect())
856 if (isCompatibleWithFields(NextKey, FieldsInSymbolicSubregions))
857 Bindings.push_back(*I);
858 } else if (const SubRegion *BaseSR = dyn_cast<SubRegion>(Base)) {
859 // Case 4: The next key is symbolic, but we changed a known
860 // super-region. In this case the binding is certainly included.
861 if (Top == Base || BaseSR->isSubRegionOf(Top))
862 if (isCompatibleWithFields(NextKey, FieldsInSymbolicSubregions))
863 Bindings.push_back(*I);
870 collectSubRegionBindings(SmallVectorImpl<BindingPair> &Bindings,
871 SValBuilder &SVB, const ClusterBindings &Cluster,
872 const SubRegion *Top, bool IncludeAllDefaultBindings) {
873 collectSubRegionBindings(Bindings, SVB, Cluster, Top,
874 BindingKey::Make(Top, BindingKey::Default),
875 IncludeAllDefaultBindings);
879 RegionStoreManager::removeSubRegionBindings(RegionBindingsConstRef B,
880 const SubRegion *Top) {
881 BindingKey TopKey = BindingKey::Make(Top, BindingKey::Default);
882 const MemRegion *ClusterHead = TopKey.getBaseRegion();
884 if (Top == ClusterHead) {
885 // We can remove an entire cluster's bindings all in one go.
886 return B.remove(Top);
889 const ClusterBindings *Cluster = B.lookup(ClusterHead);
891 // If we're invalidating a region with a symbolic offset, we need to make
892 // sure we don't treat the base region as uninitialized anymore.
893 if (TopKey.hasSymbolicOffset()) {
894 const SubRegion *Concrete = TopKey.getConcreteOffsetRegion();
895 return B.addBinding(Concrete, BindingKey::Default, UnknownVal());
900 SmallVector<BindingPair, 32> Bindings;
901 collectSubRegionBindings(Bindings, svalBuilder, *Cluster, Top, TopKey,
902 /*IncludeAllDefaultBindings=*/false);
904 ClusterBindingsRef Result(*Cluster, CBFactory);
905 for (SmallVectorImpl<BindingPair>::const_iterator I = Bindings.begin(),
908 Result = Result.remove(I->first);
910 // If we're invalidating a region with a symbolic offset, we need to make sure
911 // we don't treat the base region as uninitialized anymore.
912 // FIXME: This isn't very precise; see the example in
913 // collectSubRegionBindings.
914 if (TopKey.hasSymbolicOffset()) {
915 const SubRegion *Concrete = TopKey.getConcreteOffsetRegion();
916 Result = Result.add(BindingKey::Make(Concrete, BindingKey::Default),
920 if (Result.isEmpty())
921 return B.remove(ClusterHead);
922 return B.add(ClusterHead, Result.asImmutableMap());
926 class invalidateRegionsWorker : public ClusterAnalysis<invalidateRegionsWorker>
930 const LocationContext *LCtx;
931 InvalidatedSymbols &IS;
932 RegionAndSymbolInvalidationTraits &ITraits;
933 StoreManager::InvalidatedRegions *Regions;
934 GlobalsFilterKind GlobalsFilter;
936 invalidateRegionsWorker(RegionStoreManager &rm,
937 ProgramStateManager &stateMgr,
939 const Expr *ex, unsigned count,
940 const LocationContext *lctx,
941 InvalidatedSymbols &is,
942 RegionAndSymbolInvalidationTraits &ITraitsIn,
943 StoreManager::InvalidatedRegions *r,
944 GlobalsFilterKind GFK)
945 : ClusterAnalysis<invalidateRegionsWorker>(rm, stateMgr, b),
946 Ex(ex), Count(count), LCtx(lctx), IS(is), ITraits(ITraitsIn), Regions(r),
947 GlobalsFilter(GFK) {}
949 void VisitCluster(const MemRegion *baseR, const ClusterBindings *C);
950 void VisitBinding(SVal V);
952 using ClusterAnalysis::AddToWorkList;
954 bool AddToWorkList(const MemRegion *R);
956 /// Returns true if all clusters in the memory space for \p Base should be
958 bool includeEntireMemorySpace(const MemRegion *Base);
960 /// Returns true if the memory space of the given region is one of the global
961 /// regions specially included at the start of invalidation.
962 bool isInitiallyIncludedGlobalRegion(const MemRegion *R);
966 bool invalidateRegionsWorker::AddToWorkList(const MemRegion *R) {
967 bool doNotInvalidateSuperRegion = ITraits.hasTrait(
968 R, RegionAndSymbolInvalidationTraits::TK_DoNotInvalidateSuperRegion);
969 const MemRegion *BaseR = doNotInvalidateSuperRegion ? R : R->getBaseRegion();
970 return AddToWorkList(WorkListElement(BaseR), getCluster(BaseR));
973 void invalidateRegionsWorker::VisitBinding(SVal V) {
974 // A symbol? Mark it touched by the invalidation.
975 if (SymbolRef Sym = V.getAsSymbol())
978 if (const MemRegion *R = V.getAsRegion()) {
983 // Is it a LazyCompoundVal? All references get invalidated as well.
984 if (Optional<nonloc::LazyCompoundVal> LCS =
985 V.getAs<nonloc::LazyCompoundVal>()) {
987 const RegionStoreManager::SValListTy &Vals = RM.getInterestingValues(*LCS);
989 for (RegionStoreManager::SValListTy::const_iterator I = Vals.begin(),
998 void invalidateRegionsWorker::VisitCluster(const MemRegion *baseR,
999 const ClusterBindings *C) {
1001 bool PreserveRegionsContents =
1002 ITraits.hasTrait(baseR,
1003 RegionAndSymbolInvalidationTraits::TK_PreserveContents);
1006 for (ClusterBindings::iterator I = C->begin(), E = C->end(); I != E; ++I)
1007 VisitBinding(I.getData());
1009 // Invalidate regions contents.
1010 if (!PreserveRegionsContents)
1011 B = B.remove(baseR);
1014 // BlockDataRegion? If so, invalidate captured variables that are passed
1016 if (const BlockDataRegion *BR = dyn_cast<BlockDataRegion>(baseR)) {
1017 for (BlockDataRegion::referenced_vars_iterator
1018 BI = BR->referenced_vars_begin(), BE = BR->referenced_vars_end() ;
1020 const VarRegion *VR = BI.getCapturedRegion();
1021 const VarDecl *VD = VR->getDecl();
1022 if (VD->hasAttr<BlocksAttr>() || !VD->hasLocalStorage()) {
1025 else if (Loc::isLocType(VR->getValueType())) {
1026 // Map the current bindings to a Store to retrieve the value
1027 // of the binding. If that binding itself is a region, we should
1028 // invalidate that region. This is because a block may capture
1029 // a pointer value, but the thing pointed by that pointer may
1031 SVal V = RM.getBinding(B, loc::MemRegionVal(VR));
1032 if (Optional<Loc> L = V.getAs<Loc>()) {
1033 if (const MemRegion *LR = L->getAsRegion())
1042 if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(baseR))
1043 IS.insert(SR->getSymbol());
1045 // Nothing else should be done in the case when we preserve regions context.
1046 if (PreserveRegionsContents)
1049 // Otherwise, we have a normal data region. Record that we touched the region.
1051 Regions->push_back(baseR);
1053 if (isa<AllocaRegion>(baseR) || isa<SymbolicRegion>(baseR)) {
1054 // Invalidate the region by setting its default value to
1055 // conjured symbol. The type of the symbol is irrelevant.
1056 DefinedOrUnknownSVal V =
1057 svalBuilder.conjureSymbolVal(baseR, Ex, LCtx, Ctx.IntTy, Count);
1058 B = B.addBinding(baseR, BindingKey::Default, V);
1062 if (!baseR->isBoundable())
1065 const TypedValueRegion *TR = cast<TypedValueRegion>(baseR);
1066 QualType T = TR->getValueType();
1068 if (isInitiallyIncludedGlobalRegion(baseR)) {
1069 // If the region is a global and we are invalidating all globals,
1070 // erasing the entry is good enough. This causes all globals to be lazily
1071 // symbolicated from the same base symbol.
1075 if (T->isStructureOrClassType()) {
1076 // Invalidate the region by setting its default value to
1077 // conjured symbol. The type of the symbol is irrelevant.
1078 DefinedOrUnknownSVal V = svalBuilder.conjureSymbolVal(baseR, Ex, LCtx,
1080 B = B.addBinding(baseR, BindingKey::Default, V);
1084 if (const ArrayType *AT = Ctx.getAsArrayType(T)) {
1085 bool doNotInvalidateSuperRegion = ITraits.hasTrait(
1087 RegionAndSymbolInvalidationTraits::TK_DoNotInvalidateSuperRegion);
1089 if (doNotInvalidateSuperRegion) {
1090 // We are not doing blank invalidation of the whole array region so we
1091 // have to manually invalidate each elements.
1092 Optional<uint64_t> NumElements;
1094 // Compute lower and upper offsets for region within array.
1095 if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
1096 NumElements = CAT->getSize().getZExtValue();
1097 if (!NumElements) // We are not dealing with a constant size array
1098 goto conjure_default;
1099 QualType ElementTy = AT->getElementType();
1100 uint64_t ElemSize = Ctx.getTypeSize(ElementTy);
1101 const RegionOffset &RO = baseR->getAsOffset();
1102 const MemRegion *SuperR = baseR->getBaseRegion();
1103 if (RO.hasSymbolicOffset()) {
1104 // If base region has a symbolic offset,
1105 // we revert to invalidating the super region.
1107 AddToWorkList(SuperR);
1108 goto conjure_default;
1111 uint64_t LowerOffset = RO.getOffset();
1112 uint64_t UpperOffset = LowerOffset + *NumElements * ElemSize;
1113 bool UpperOverflow = UpperOffset < LowerOffset;
1115 // Invalidate regions which are within array boundaries,
1116 // or have a symbolic offset.
1118 goto conjure_default;
1120 const ClusterBindings *C = B.lookup(SuperR);
1122 goto conjure_default;
1124 for (ClusterBindings::iterator I = C->begin(), E = C->end(); I != E;
1126 const BindingKey &BK = I.getKey();
1127 Optional<uint64_t> ROffset =
1128 BK.hasSymbolicOffset() ? Optional<uint64_t>() : BK.getOffset();
1130 // Check offset is not symbolic and within array's boundaries.
1131 // Handles arrays of 0 elements and of 0-sized elements as well.
1133 ((*ROffset >= LowerOffset && *ROffset < UpperOffset) ||
1135 (*ROffset >= LowerOffset || *ROffset < UpperOffset)) ||
1136 (LowerOffset == UpperOffset && *ROffset == LowerOffset))) {
1137 B = B.removeBinding(I.getKey());
1138 // Bound symbolic regions need to be invalidated for dead symbol
1140 SVal V = I.getData();
1141 const MemRegion *R = V.getAsRegion();
1142 if (R && isa<SymbolicRegion>(R))
1148 // Set the default value of the array to conjured symbol.
1149 DefinedOrUnknownSVal V =
1150 svalBuilder.conjureSymbolVal(baseR, Ex, LCtx,
1151 AT->getElementType(), Count);
1152 B = B.addBinding(baseR, BindingKey::Default, V);
1156 DefinedOrUnknownSVal V = svalBuilder.conjureSymbolVal(baseR, Ex, LCtx,
1158 assert(SymbolManager::canSymbolicate(T) || V.isUnknown());
1159 B = B.addBinding(baseR, BindingKey::Direct, V);
1162 bool invalidateRegionsWorker::isInitiallyIncludedGlobalRegion(
1163 const MemRegion *R) {
1164 switch (GlobalsFilter) {
1167 case GFK_SystemOnly:
1168 return isa<GlobalSystemSpaceRegion>(R->getMemorySpace());
1170 return isa<NonStaticGlobalSpaceRegion>(R->getMemorySpace());
1173 llvm_unreachable("unknown globals filter");
1176 bool invalidateRegionsWorker::includeEntireMemorySpace(const MemRegion *Base) {
1177 if (isInitiallyIncludedGlobalRegion(Base))
1180 const MemSpaceRegion *MemSpace = Base->getMemorySpace();
1181 return ITraits.hasTrait(MemSpace,
1182 RegionAndSymbolInvalidationTraits::TK_EntireMemSpace);
1186 RegionStoreManager::invalidateGlobalRegion(MemRegion::Kind K,
1189 const LocationContext *LCtx,
1190 RegionBindingsRef B,
1191 InvalidatedRegions *Invalidated) {
1192 // Bind the globals memory space to a new symbol that we will use to derive
1193 // the bindings for all globals.
1194 const GlobalsSpaceRegion *GS = MRMgr.getGlobalsRegion(K);
1195 SVal V = svalBuilder.conjureSymbolVal(/* SymbolTag = */ (const void*) GS, Ex, LCtx,
1196 /* type does not matter */ Ctx.IntTy,
1199 B = B.removeBinding(GS)
1200 .addBinding(BindingKey::Make(GS, BindingKey::Default), V);
1202 // Even if there are no bindings in the global scope, we still need to
1203 // record that we touched it.
1205 Invalidated->push_back(GS);
1210 void RegionStoreManager::populateWorkList(invalidateRegionsWorker &W,
1211 ArrayRef<SVal> Values,
1212 InvalidatedRegions *TopLevelRegions) {
1213 for (ArrayRef<SVal>::iterator I = Values.begin(),
1214 E = Values.end(); I != E; ++I) {
1216 if (Optional<nonloc::LazyCompoundVal> LCS =
1217 V.getAs<nonloc::LazyCompoundVal>()) {
1219 const SValListTy &Vals = getInterestingValues(*LCS);
1221 for (SValListTy::const_iterator I = Vals.begin(),
1222 E = Vals.end(); I != E; ++I) {
1223 // Note: the last argument is false here because these are
1224 // non-top-level regions.
1225 if (const MemRegion *R = (*I).getAsRegion())
1231 if (const MemRegion *R = V.getAsRegion()) {
1232 if (TopLevelRegions)
1233 TopLevelRegions->push_back(R);
1241 RegionStoreManager::invalidateRegions(Store store,
1242 ArrayRef<SVal> Values,
1243 const Expr *Ex, unsigned Count,
1244 const LocationContext *LCtx,
1245 const CallEvent *Call,
1246 InvalidatedSymbols &IS,
1247 RegionAndSymbolInvalidationTraits &ITraits,
1248 InvalidatedRegions *TopLevelRegions,
1249 InvalidatedRegions *Invalidated) {
1250 GlobalsFilterKind GlobalsFilter;
1252 if (Call->isInSystemHeader())
1253 GlobalsFilter = GFK_SystemOnly;
1255 GlobalsFilter = GFK_All;
1257 GlobalsFilter = GFK_None;
1260 RegionBindingsRef B = getRegionBindings(store);
1261 invalidateRegionsWorker W(*this, StateMgr, B, Ex, Count, LCtx, IS, ITraits,
1262 Invalidated, GlobalsFilter);
1264 // Scan the bindings and generate the clusters.
1265 W.GenerateClusters();
1267 // Add the regions to the worklist.
1268 populateWorkList(W, Values, TopLevelRegions);
1272 // Return the new bindings.
1273 B = W.getRegionBindings();
1275 // For calls, determine which global regions should be invalidated and
1276 // invalidate them. (Note that function-static and immutable globals are never
1277 // invalidated by this.)
1278 // TODO: This could possibly be more precise with modules.
1279 switch (GlobalsFilter) {
1281 B = invalidateGlobalRegion(MemRegion::GlobalInternalSpaceRegionKind,
1282 Ex, Count, LCtx, B, Invalidated);
1284 case GFK_SystemOnly:
1285 B = invalidateGlobalRegion(MemRegion::GlobalSystemSpaceRegionKind,
1286 Ex, Count, LCtx, B, Invalidated);
1292 return StoreRef(B.asStore(), *this);
1295 //===----------------------------------------------------------------------===//
1296 // Extents for regions.
1297 //===----------------------------------------------------------------------===//
1299 DefinedOrUnknownSVal
1300 RegionStoreManager::getSizeInElements(ProgramStateRef state,
1303 SVal Size = cast<SubRegion>(R)->getExtent(svalBuilder);
1304 const llvm::APSInt *SizeInt = svalBuilder.getKnownValue(state, Size);
1306 return UnknownVal();
1308 CharUnits RegionSize = CharUnits::fromQuantity(SizeInt->getSExtValue());
1310 if (Ctx.getAsVariableArrayType(EleTy)) {
1311 // FIXME: We need to track extra state to properly record the size
1312 // of VLAs. Returning UnknownVal here, however, is a stop-gap so that
1313 // we don't have a divide-by-zero below.
1314 return UnknownVal();
1317 CharUnits EleSize = Ctx.getTypeSizeInChars(EleTy);
1319 // If a variable is reinterpreted as a type that doesn't fit into a larger
1320 // type evenly, round it down.
1321 // This is a signed value, since it's used in arithmetic with signed indices.
1322 return svalBuilder.makeIntVal(RegionSize / EleSize, false);
1325 //===----------------------------------------------------------------------===//
1326 // Location and region casting.
1327 //===----------------------------------------------------------------------===//
1329 /// ArrayToPointer - Emulates the "decay" of an array to a pointer
1330 /// type. 'Array' represents the lvalue of the array being decayed
1331 /// to a pointer, and the returned SVal represents the decayed
1332 /// version of that lvalue (i.e., a pointer to the first element of
1333 /// the array). This is called by ExprEngine when evaluating casts
1334 /// from arrays to pointers.
1335 SVal RegionStoreManager::ArrayToPointer(Loc Array, QualType T) {
1336 if (!Array.getAs<loc::MemRegionVal>())
1337 return UnknownVal();
1339 const MemRegion* R = Array.castAs<loc::MemRegionVal>().getRegion();
1340 NonLoc ZeroIdx = svalBuilder.makeZeroArrayIndex();
1341 return loc::MemRegionVal(MRMgr.getElementRegion(T, ZeroIdx, R, Ctx));
1344 //===----------------------------------------------------------------------===//
1345 // Loading values from regions.
1346 //===----------------------------------------------------------------------===//
1348 SVal RegionStoreManager::getBinding(RegionBindingsConstRef B, Loc L, QualType T) {
1349 assert(!L.getAs<UnknownVal>() && "location unknown");
1350 assert(!L.getAs<UndefinedVal>() && "location undefined");
1352 // For access to concrete addresses, return UnknownVal. Checks
1353 // for null dereferences (and similar errors) are done by checkers, not
1355 // FIXME: We can consider lazily symbolicating such memory, but we really
1356 // should defer this when we can reason easily about symbolicating arrays
1358 if (L.getAs<loc::ConcreteInt>()) {
1359 return UnknownVal();
1361 if (!L.getAs<loc::MemRegionVal>()) {
1362 return UnknownVal();
1365 const MemRegion *MR = L.castAs<loc::MemRegionVal>().getRegion();
1367 if (isa<BlockDataRegion>(MR)) {
1368 return UnknownVal();
1371 if (isa<AllocaRegion>(MR) ||
1372 isa<SymbolicRegion>(MR) ||
1373 isa<CodeTextRegion>(MR)) {
1375 if (const TypedRegion *TR = dyn_cast<TypedRegion>(MR))
1376 T = TR->getLocationType();
1378 const SymbolicRegion *SR = cast<SymbolicRegion>(MR);
1379 T = SR->getSymbol()->getType();
1382 MR = GetElementZeroRegion(MR, T);
1385 // FIXME: Perhaps this method should just take a 'const MemRegion*' argument
1386 // instead of 'Loc', and have the other Loc cases handled at a higher level.
1387 const TypedValueRegion *R = cast<TypedValueRegion>(MR);
1388 QualType RTy = R->getValueType();
1390 // FIXME: we do not yet model the parts of a complex type, so treat the
1391 // whole thing as "unknown".
1392 if (RTy->isAnyComplexType())
1393 return UnknownVal();
1395 // FIXME: We should eventually handle funny addressing. e.g.:
1399 // char *q = (char*) p;
1400 // char c = *q; // returns the first byte of 'x'.
1402 // Such funny addressing will occur due to layering of regions.
1403 if (RTy->isStructureOrClassType())
1404 return getBindingForStruct(B, R);
1406 // FIXME: Handle unions.
1407 if (RTy->isUnionType())
1408 return createLazyBinding(B, R);
1410 if (RTy->isArrayType()) {
1411 if (RTy->isConstantArrayType())
1412 return getBindingForArray(B, R);
1414 return UnknownVal();
1417 // FIXME: handle Vector types.
1418 if (RTy->isVectorType())
1419 return UnknownVal();
1421 if (const FieldRegion* FR = dyn_cast<FieldRegion>(R))
1422 return CastRetrievedVal(getBindingForField(B, FR), FR, T, false);
1424 if (const ElementRegion* ER = dyn_cast<ElementRegion>(R)) {
1425 // FIXME: Here we actually perform an implicit conversion from the loaded
1426 // value to the element type. Eventually we want to compose these values
1427 // more intelligently. For example, an 'element' can encompass multiple
1428 // bound regions (e.g., several bound bytes), or could be a subset of
1430 return CastRetrievedVal(getBindingForElement(B, ER), ER, T, false);
1433 if (const ObjCIvarRegion *IVR = dyn_cast<ObjCIvarRegion>(R)) {
1434 // FIXME: Here we actually perform an implicit conversion from the loaded
1435 // value to the ivar type. What we should model is stores to ivars
1436 // that blow past the extent of the ivar. If the address of the ivar is
1437 // reinterpretted, it is possible we stored a different value that could
1438 // fit within the ivar. Either we need to cast these when storing them
1439 // or reinterpret them lazily (as we do here).
1440 return CastRetrievedVal(getBindingForObjCIvar(B, IVR), IVR, T, false);
1443 if (const VarRegion *VR = dyn_cast<VarRegion>(R)) {
1444 // FIXME: Here we actually perform an implicit conversion from the loaded
1445 // value to the variable type. What we should model is stores to variables
1446 // that blow past the extent of the variable. If the address of the
1447 // variable is reinterpretted, it is possible we stored a different value
1448 // that could fit within the variable. Either we need to cast these when
1449 // storing them or reinterpret them lazily (as we do here).
1450 return CastRetrievedVal(getBindingForVar(B, VR), VR, T, false);
1453 const SVal *V = B.lookup(R, BindingKey::Direct);
1455 // Check if the region has a binding.
1459 // The location does not have a bound value. This means that it has
1460 // the value it had upon its creation and/or entry to the analyzed
1461 // function/method. These are either symbolic values or 'undefined'.
1462 if (R->hasStackNonParametersStorage()) {
1463 // All stack variables are considered to have undefined values
1464 // upon creation. All heap allocated blocks are considered to
1465 // have undefined values as well unless they are explicitly bound
1466 // to specific values.
1467 return UndefinedVal();
1470 // All other values are symbolic.
1471 return svalBuilder.getRegionValueSymbolVal(R);
1474 static QualType getUnderlyingType(const SubRegion *R) {
1476 if (const TypedValueRegion *TVR = dyn_cast<TypedValueRegion>(R))
1477 RegionTy = TVR->getValueType();
1479 if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R))
1480 RegionTy = SR->getSymbol()->getType();
1485 /// Checks to see if store \p B has a lazy binding for region \p R.
1487 /// If \p AllowSubregionBindings is \c false, a lazy binding will be rejected
1488 /// if there are additional bindings within \p R.
1490 /// Note that unlike RegionStoreManager::findLazyBinding, this will not search
1491 /// for lazy bindings for super-regions of \p R.
1492 static Optional<nonloc::LazyCompoundVal>
1493 getExistingLazyBinding(SValBuilder &SVB, RegionBindingsConstRef B,
1494 const SubRegion *R, bool AllowSubregionBindings) {
1495 Optional<SVal> V = B.getDefaultBinding(R);
1499 Optional<nonloc::LazyCompoundVal> LCV = V->getAs<nonloc::LazyCompoundVal>();
1503 // If the LCV is for a subregion, the types might not match, and we shouldn't
1504 // reuse the binding.
1505 QualType RegionTy = getUnderlyingType(R);
1506 if (!RegionTy.isNull() &&
1507 !RegionTy->isVoidPointerType()) {
1508 QualType SourceRegionTy = LCV->getRegion()->getValueType();
1509 if (!SVB.getContext().hasSameUnqualifiedType(RegionTy, SourceRegionTy))
1513 if (!AllowSubregionBindings) {
1514 // If there are any other bindings within this region, we shouldn't reuse
1515 // the top-level binding.
1516 SmallVector<BindingPair, 16> Bindings;
1517 collectSubRegionBindings(Bindings, SVB, *B.lookup(R->getBaseRegion()), R,
1518 /*IncludeAllDefaultBindings=*/true);
1519 if (Bindings.size() > 1)
1527 std::pair<Store, const SubRegion *>
1528 RegionStoreManager::findLazyBinding(RegionBindingsConstRef B,
1530 const SubRegion *originalRegion) {
1531 if (originalRegion != R) {
1532 if (Optional<nonloc::LazyCompoundVal> V =
1533 getExistingLazyBinding(svalBuilder, B, R, true))
1534 return std::make_pair(V->getStore(), V->getRegion());
1537 typedef std::pair<Store, const SubRegion *> StoreRegionPair;
1538 StoreRegionPair Result = StoreRegionPair();
1540 if (const ElementRegion *ER = dyn_cast<ElementRegion>(R)) {
1541 Result = findLazyBinding(B, cast<SubRegion>(ER->getSuperRegion()),
1545 Result.second = MRMgr.getElementRegionWithSuper(ER, Result.second);
1547 } else if (const FieldRegion *FR = dyn_cast<FieldRegion>(R)) {
1548 Result = findLazyBinding(B, cast<SubRegion>(FR->getSuperRegion()),
1552 Result.second = MRMgr.getFieldRegionWithSuper(FR, Result.second);
1554 } else if (const CXXBaseObjectRegion *BaseReg =
1555 dyn_cast<CXXBaseObjectRegion>(R)) {
1556 // C++ base object region is another kind of region that we should blast
1557 // through to look for lazy compound value. It is like a field region.
1558 Result = findLazyBinding(B, cast<SubRegion>(BaseReg->getSuperRegion()),
1562 Result.second = MRMgr.getCXXBaseObjectRegionWithSuper(BaseReg,
1569 SVal RegionStoreManager::getBindingForElement(RegionBindingsConstRef B,
1570 const ElementRegion* R) {
1571 // We do not currently model bindings of the CompoundLiteralregion.
1572 if (isa<CompoundLiteralRegion>(R->getBaseRegion()))
1573 return UnknownVal();
1575 // Check if the region has a binding.
1576 if (const Optional<SVal> &V = B.getDirectBinding(R))
1579 const MemRegion* superR = R->getSuperRegion();
1581 // Check if the region is an element region of a string literal.
1582 if (const StringRegion *StrR=dyn_cast<StringRegion>(superR)) {
1583 // FIXME: Handle loads from strings where the literal is treated as
1584 // an integer, e.g., *((unsigned int*)"hello")
1585 QualType T = Ctx.getAsArrayType(StrR->getValueType())->getElementType();
1586 if (!Ctx.hasSameUnqualifiedType(T, R->getElementType()))
1587 return UnknownVal();
1589 const StringLiteral *Str = StrR->getStringLiteral();
1590 SVal Idx = R->getIndex();
1591 if (Optional<nonloc::ConcreteInt> CI = Idx.getAs<nonloc::ConcreteInt>()) {
1592 int64_t i = CI->getValue().getSExtValue();
1593 // Abort on string underrun. This can be possible by arbitrary
1594 // clients of getBindingForElement().
1596 return UndefinedVal();
1597 int64_t length = Str->getLength();
1598 // Technically, only i == length is guaranteed to be null.
1599 // However, such overflows should be caught before reaching this point;
1600 // the only time such an access would be made is if a string literal was
1601 // used to initialize a larger array.
1602 char c = (i >= length) ? '\0' : Str->getCodeUnit(i);
1603 return svalBuilder.makeIntVal(c, T);
1607 // Check for loads from a code text region. For such loads, just give up.
1608 if (isa<CodeTextRegion>(superR))
1609 return UnknownVal();
1611 // Handle the case where we are indexing into a larger scalar object.
1612 // For example, this handles:
1616 // FIXME: This is a hack, and doesn't do anything really intelligent yet.
1617 const RegionRawOffset &O = R->getAsArrayOffset();
1619 // If we cannot reason about the offset, return an unknown value.
1621 return UnknownVal();
1623 if (const TypedValueRegion *baseR =
1624 dyn_cast_or_null<TypedValueRegion>(O.getRegion())) {
1625 QualType baseT = baseR->getValueType();
1626 if (baseT->isScalarType()) {
1627 QualType elemT = R->getElementType();
1628 if (elemT->isScalarType()) {
1629 if (Ctx.getTypeSizeInChars(baseT) >= Ctx.getTypeSizeInChars(elemT)) {
1630 if (const Optional<SVal> &V = B.getDirectBinding(superR)) {
1631 if (SymbolRef parentSym = V->getAsSymbol())
1632 return svalBuilder.getDerivedRegionValueSymbolVal(parentSym, R);
1634 if (V->isUnknownOrUndef())
1636 // Other cases: give up. We are indexing into a larger object
1637 // that has some value, but we don't know how to handle that yet.
1638 return UnknownVal();
1644 return getBindingForFieldOrElementCommon(B, R, R->getElementType());
1647 SVal RegionStoreManager::getBindingForField(RegionBindingsConstRef B,
1648 const FieldRegion* R) {
1650 // Check if the region has a binding.
1651 if (const Optional<SVal> &V = B.getDirectBinding(R))
1654 QualType Ty = R->getValueType();
1655 return getBindingForFieldOrElementCommon(B, R, Ty);
1659 RegionStoreManager::getBindingForDerivedDefaultValue(RegionBindingsConstRef B,
1660 const MemRegion *superR,
1661 const TypedValueRegion *R,
1664 if (const Optional<SVal> &D = B.getDefaultBinding(superR)) {
1665 const SVal &val = D.getValue();
1666 if (SymbolRef parentSym = val.getAsSymbol())
1667 return svalBuilder.getDerivedRegionValueSymbolVal(parentSym, R);
1669 if (val.isZeroConstant())
1670 return svalBuilder.makeZeroVal(Ty);
1672 if (val.isUnknownOrUndef())
1675 // Lazy bindings are usually handled through getExistingLazyBinding().
1676 // We should unify these two code paths at some point.
1677 if (val.getAs<nonloc::LazyCompoundVal>() ||
1678 val.getAs<nonloc::CompoundVal>())
1681 llvm_unreachable("Unknown default value");
1687 SVal RegionStoreManager::getLazyBinding(const SubRegion *LazyBindingRegion,
1688 RegionBindingsRef LazyBinding) {
1690 if (const ElementRegion *ER = dyn_cast<ElementRegion>(LazyBindingRegion))
1691 Result = getBindingForElement(LazyBinding, ER);
1693 Result = getBindingForField(LazyBinding,
1694 cast<FieldRegion>(LazyBindingRegion));
1696 // FIXME: This is a hack to deal with RegionStore's inability to distinguish a
1697 // default value for /part/ of an aggregate from a default value for the
1698 // /entire/ aggregate. The most common case of this is when struct Outer
1699 // has as its first member a struct Inner, which is copied in from a stack
1700 // variable. In this case, even if the Outer's default value is symbolic, 0,
1701 // or unknown, it gets overridden by the Inner's default value of undefined.
1703 // This is a general problem -- if the Inner is zero-initialized, the Outer
1704 // will now look zero-initialized. The proper way to solve this is with a
1705 // new version of RegionStore that tracks the extent of a binding as well
1708 // This hack only takes care of the undefined case because that can very
1709 // quickly result in a warning.
1710 if (Result.isUndef())
1711 Result = UnknownVal();
1717 RegionStoreManager::getBindingForFieldOrElementCommon(RegionBindingsConstRef B,
1718 const TypedValueRegion *R,
1721 // At this point we have already checked in either getBindingForElement or
1722 // getBindingForField if 'R' has a direct binding.
1725 Store lazyBindingStore = nullptr;
1726 const SubRegion *lazyBindingRegion = nullptr;
1727 std::tie(lazyBindingStore, lazyBindingRegion) = findLazyBinding(B, R, R);
1728 if (lazyBindingRegion)
1729 return getLazyBinding(lazyBindingRegion,
1730 getRegionBindings(lazyBindingStore));
1732 // Record whether or not we see a symbolic index. That can completely
1733 // be out of scope of our lookup.
1734 bool hasSymbolicIndex = false;
1736 // FIXME: This is a hack to deal with RegionStore's inability to distinguish a
1737 // default value for /part/ of an aggregate from a default value for the
1738 // /entire/ aggregate. The most common case of this is when struct Outer
1739 // has as its first member a struct Inner, which is copied in from a stack
1740 // variable. In this case, even if the Outer's default value is symbolic, 0,
1741 // or unknown, it gets overridden by the Inner's default value of undefined.
1743 // This is a general problem -- if the Inner is zero-initialized, the Outer
1744 // will now look zero-initialized. The proper way to solve this is with a
1745 // new version of RegionStore that tracks the extent of a binding as well
1748 // This hack only takes care of the undefined case because that can very
1749 // quickly result in a warning.
1750 bool hasPartialLazyBinding = false;
1752 const SubRegion *SR = dyn_cast<SubRegion>(R);
1754 const MemRegion *Base = SR->getSuperRegion();
1755 if (Optional<SVal> D = getBindingForDerivedDefaultValue(B, Base, R, Ty)) {
1756 if (D->getAs<nonloc::LazyCompoundVal>()) {
1757 hasPartialLazyBinding = true;
1764 if (const ElementRegion *ER = dyn_cast<ElementRegion>(Base)) {
1765 NonLoc index = ER->getIndex();
1766 if (!index.isConstant())
1767 hasSymbolicIndex = true;
1770 // If our super region is a field or element itself, walk up the region
1771 // hierarchy to see if there is a default value installed in an ancestor.
1772 SR = dyn_cast<SubRegion>(Base);
1775 if (R->hasStackNonParametersStorage()) {
1776 if (isa<ElementRegion>(R)) {
1777 // Currently we don't reason specially about Clang-style vectors. Check
1778 // if superR is a vector and if so return Unknown.
1779 if (const TypedValueRegion *typedSuperR =
1780 dyn_cast<TypedValueRegion>(R->getSuperRegion())) {
1781 if (typedSuperR->getValueType()->isVectorType())
1782 return UnknownVal();
1786 // FIXME: We also need to take ElementRegions with symbolic indexes into
1787 // account. This case handles both directly accessing an ElementRegion
1788 // with a symbolic offset, but also fields within an element with
1789 // a symbolic offset.
1790 if (hasSymbolicIndex)
1791 return UnknownVal();
1793 if (!hasPartialLazyBinding)
1794 return UndefinedVal();
1797 // All other values are symbolic.
1798 return svalBuilder.getRegionValueSymbolVal(R);
1801 SVal RegionStoreManager::getBindingForObjCIvar(RegionBindingsConstRef B,
1802 const ObjCIvarRegion* R) {
1803 // Check if the region has a binding.
1804 if (const Optional<SVal> &V = B.getDirectBinding(R))
1807 const MemRegion *superR = R->getSuperRegion();
1809 // Check if the super region has a default binding.
1810 if (const Optional<SVal> &V = B.getDefaultBinding(superR)) {
1811 if (SymbolRef parentSym = V->getAsSymbol())
1812 return svalBuilder.getDerivedRegionValueSymbolVal(parentSym, R);
1814 // Other cases: give up.
1815 return UnknownVal();
1818 return getBindingForLazySymbol(R);
1821 SVal RegionStoreManager::getBindingForVar(RegionBindingsConstRef B,
1822 const VarRegion *R) {
1824 // Check if the region has a binding.
1825 if (const Optional<SVal> &V = B.getDirectBinding(R))
1828 // Lazily derive a value for the VarRegion.
1829 const VarDecl *VD = R->getDecl();
1830 const MemSpaceRegion *MS = R->getMemorySpace();
1832 // Arguments are always symbolic.
1833 if (isa<StackArgumentsSpaceRegion>(MS))
1834 return svalBuilder.getRegionValueSymbolVal(R);
1836 // Is 'VD' declared constant? If so, retrieve the constant value.
1837 if (VD->getType().isConstQualified())
1838 if (const Expr *Init = VD->getInit())
1839 if (Optional<SVal> V = svalBuilder.getConstantVal(Init))
1842 // This must come after the check for constants because closure-captured
1843 // constant variables may appear in UnknownSpaceRegion.
1844 if (isa<UnknownSpaceRegion>(MS))
1845 return svalBuilder.getRegionValueSymbolVal(R);
1847 if (isa<GlobalsSpaceRegion>(MS)) {
1848 QualType T = VD->getType();
1850 // Function-scoped static variables are default-initialized to 0; if they
1851 // have an initializer, it would have been processed by now.
1852 // FIXME: This is only true when we're starting analysis from main().
1853 // We're losing a lot of coverage here.
1854 if (isa<StaticGlobalSpaceRegion>(MS))
1855 return svalBuilder.makeZeroVal(T);
1857 if (Optional<SVal> V = getBindingForDerivedDefaultValue(B, MS, R, T)) {
1858 assert(!V->getAs<nonloc::LazyCompoundVal>());
1859 return V.getValue();
1862 return svalBuilder.getRegionValueSymbolVal(R);
1865 return UndefinedVal();
1868 SVal RegionStoreManager::getBindingForLazySymbol(const TypedValueRegion *R) {
1869 // All other values are symbolic.
1870 return svalBuilder.getRegionValueSymbolVal(R);
1873 const RegionStoreManager::SValListTy &
1874 RegionStoreManager::getInterestingValues(nonloc::LazyCompoundVal LCV) {
1875 // First, check the cache.
1876 LazyBindingsMapTy::iterator I = LazyBindingsMap.find(LCV.getCVData());
1877 if (I != LazyBindingsMap.end())
1880 // If we don't have a list of values cached, start constructing it.
1883 const SubRegion *LazyR = LCV.getRegion();
1884 RegionBindingsRef B = getRegionBindings(LCV.getStore());
1886 // If this region had /no/ bindings at the time, there are no interesting
1887 // values to return.
1888 const ClusterBindings *Cluster = B.lookup(LazyR->getBaseRegion());
1890 return (LazyBindingsMap[LCV.getCVData()] = std::move(List));
1892 SmallVector<BindingPair, 32> Bindings;
1893 collectSubRegionBindings(Bindings, svalBuilder, *Cluster, LazyR,
1894 /*IncludeAllDefaultBindings=*/true);
1895 for (SmallVectorImpl<BindingPair>::const_iterator I = Bindings.begin(),
1899 if (V.isUnknownOrUndef() || V.isConstant())
1902 if (Optional<nonloc::LazyCompoundVal> InnerLCV =
1903 V.getAs<nonloc::LazyCompoundVal>()) {
1904 const SValListTy &InnerList = getInterestingValues(*InnerLCV);
1905 List.insert(List.end(), InnerList.begin(), InnerList.end());
1912 return (LazyBindingsMap[LCV.getCVData()] = std::move(List));
1915 NonLoc RegionStoreManager::createLazyBinding(RegionBindingsConstRef B,
1916 const TypedValueRegion *R) {
1917 if (Optional<nonloc::LazyCompoundVal> V =
1918 getExistingLazyBinding(svalBuilder, B, R, false))
1921 return svalBuilder.makeLazyCompoundVal(StoreRef(B.asStore(), *this), R);
1924 static bool isRecordEmpty(const RecordDecl *RD) {
1925 if (!RD->field_empty())
1927 if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD))
1928 return CRD->getNumBases() == 0;
1932 SVal RegionStoreManager::getBindingForStruct(RegionBindingsConstRef B,
1933 const TypedValueRegion *R) {
1934 const RecordDecl *RD = R->getValueType()->castAs<RecordType>()->getDecl();
1935 if (!RD->getDefinition() || isRecordEmpty(RD))
1936 return UnknownVal();
1938 return createLazyBinding(B, R);
1941 SVal RegionStoreManager::getBindingForArray(RegionBindingsConstRef B,
1942 const TypedValueRegion *R) {
1943 assert(Ctx.getAsConstantArrayType(R->getValueType()) &&
1944 "Only constant array types can have compound bindings.");
1946 return createLazyBinding(B, R);
1949 bool RegionStoreManager::includedInBindings(Store store,
1950 const MemRegion *region) const {
1951 RegionBindingsRef B = getRegionBindings(store);
1952 region = region->getBaseRegion();
1954 // Quick path: if the base is the head of a cluster, the region is live.
1955 if (B.lookup(region))
1958 // Slow path: if the region is the VALUE of any binding, it is live.
1959 for (RegionBindingsRef::iterator RI = B.begin(), RE = B.end(); RI != RE; ++RI) {
1960 const ClusterBindings &Cluster = RI.getData();
1961 for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end();
1963 const SVal &D = CI.getData();
1964 if (const MemRegion *R = D.getAsRegion())
1965 if (R->getBaseRegion() == region)
1973 //===----------------------------------------------------------------------===//
1974 // Binding values to regions.
1975 //===----------------------------------------------------------------------===//
1977 StoreRef RegionStoreManager::killBinding(Store ST, Loc L) {
1978 if (Optional<loc::MemRegionVal> LV = L.getAs<loc::MemRegionVal>())
1979 if (const MemRegion* R = LV->getRegion())
1980 return StoreRef(getRegionBindings(ST).removeBinding(R)
1982 .getRootWithoutRetain(),
1985 return StoreRef(ST, *this);
1989 RegionStoreManager::bind(RegionBindingsConstRef B, Loc L, SVal V) {
1990 if (L.getAs<loc::ConcreteInt>())
1993 // If we get here, the location should be a region.
1994 const MemRegion *R = L.castAs<loc::MemRegionVal>().getRegion();
1996 // Check if the region is a struct region.
1997 if (const TypedValueRegion* TR = dyn_cast<TypedValueRegion>(R)) {
1998 QualType Ty = TR->getValueType();
1999 if (Ty->isArrayType())
2000 return bindArray(B, TR, V);
2001 if (Ty->isStructureOrClassType())
2002 return bindStruct(B, TR, V);
2003 if (Ty->isVectorType())
2004 return bindVector(B, TR, V);
2005 if (Ty->isUnionType())
2006 return bindAggregate(B, TR, V);
2009 if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) {
2010 // Binding directly to a symbolic region should be treated as binding
2012 QualType T = SR->getSymbol()->getType();
2013 if (T->isAnyPointerType() || T->isReferenceType())
2014 T = T->getPointeeType();
2016 R = GetElementZeroRegion(SR, T);
2019 // Clear out bindings that may overlap with this binding.
2020 RegionBindingsRef NewB = removeSubRegionBindings(B, cast<SubRegion>(R));
2021 return NewB.addBinding(BindingKey::Make(R, BindingKey::Direct), V);
2025 RegionStoreManager::setImplicitDefaultValue(RegionBindingsConstRef B,
2030 if (Loc::isLocType(T))
2031 V = svalBuilder.makeNull();
2032 else if (T->isIntegralOrEnumerationType())
2033 V = svalBuilder.makeZeroVal(T);
2034 else if (T->isStructureOrClassType() || T->isArrayType()) {
2035 // Set the default value to a zero constant when it is a structure
2036 // or array. The type doesn't really matter.
2037 V = svalBuilder.makeZeroVal(Ctx.IntTy);
2040 // We can't represent values of this type, but we still need to set a value
2041 // to record that the region has been initialized.
2042 // If this assertion ever fires, a new case should be added above -- we
2043 // should know how to default-initialize any value we can symbolicate.
2044 assert(!SymbolManager::canSymbolicate(T) && "This type is representable");
2048 return B.addBinding(R, BindingKey::Default, V);
2052 RegionStoreManager::bindArray(RegionBindingsConstRef B,
2053 const TypedValueRegion* R,
2056 const ArrayType *AT =cast<ArrayType>(Ctx.getCanonicalType(R->getValueType()));
2057 QualType ElementTy = AT->getElementType();
2058 Optional<uint64_t> Size;
2060 if (const ConstantArrayType* CAT = dyn_cast<ConstantArrayType>(AT))
2061 Size = CAT->getSize().getZExtValue();
2063 // Check if the init expr is a string literal.
2064 if (Optional<loc::MemRegionVal> MRV = Init.getAs<loc::MemRegionVal>()) {
2065 const StringRegion *S = cast<StringRegion>(MRV->getRegion());
2067 // Treat the string as a lazy compound value.
2068 StoreRef store(B.asStore(), *this);
2069 nonloc::LazyCompoundVal LCV = svalBuilder.makeLazyCompoundVal(store, S)
2070 .castAs<nonloc::LazyCompoundVal>();
2071 return bindAggregate(B, R, LCV);
2074 // Handle lazy compound values.
2075 if (Init.getAs<nonloc::LazyCompoundVal>())
2076 return bindAggregate(B, R, Init);
2078 if (Init.isUnknown())
2079 return bindAggregate(B, R, UnknownVal());
2081 // Remaining case: explicit compound values.
2082 const nonloc::CompoundVal& CV = Init.castAs<nonloc::CompoundVal>();
2083 nonloc::CompoundVal::iterator VI = CV.begin(), VE = CV.end();
2086 RegionBindingsRef NewB(B);
2088 for (; Size.hasValue() ? i < Size.getValue() : true ; ++i, ++VI) {
2089 // The init list might be shorter than the array length.
2093 const NonLoc &Idx = svalBuilder.makeArrayIndex(i);
2094 const ElementRegion *ER = MRMgr.getElementRegion(ElementTy, Idx, R, Ctx);
2096 if (ElementTy->isStructureOrClassType())
2097 NewB = bindStruct(NewB, ER, *VI);
2098 else if (ElementTy->isArrayType())
2099 NewB = bindArray(NewB, ER, *VI);
2101 NewB = bind(NewB, loc::MemRegionVal(ER), *VI);
2104 // If the init list is shorter than the array length, set the
2105 // array default value.
2106 if (Size.hasValue() && i < Size.getValue())
2107 NewB = setImplicitDefaultValue(NewB, R, ElementTy);
2112 RegionBindingsRef RegionStoreManager::bindVector(RegionBindingsConstRef B,
2113 const TypedValueRegion* R,
2115 QualType T = R->getValueType();
2116 assert(T->isVectorType());
2117 const VectorType *VT = T->getAs<VectorType>(); // Use getAs for typedefs.
2119 // Handle lazy compound values and symbolic values.
2120 if (V.getAs<nonloc::LazyCompoundVal>() || V.getAs<nonloc::SymbolVal>())
2121 return bindAggregate(B, R, V);
2123 // We may get non-CompoundVal accidentally due to imprecise cast logic or
2124 // that we are binding symbolic struct value. Kill the field values, and if
2125 // the value is symbolic go and bind it as a "default" binding.
2126 if (!V.getAs<nonloc::CompoundVal>()) {
2127 return bindAggregate(B, R, UnknownVal());
2130 QualType ElemType = VT->getElementType();
2131 nonloc::CompoundVal CV = V.castAs<nonloc::CompoundVal>();
2132 nonloc::CompoundVal::iterator VI = CV.begin(), VE = CV.end();
2133 unsigned index = 0, numElements = VT->getNumElements();
2134 RegionBindingsRef NewB(B);
2136 for ( ; index != numElements ; ++index) {
2140 NonLoc Idx = svalBuilder.makeArrayIndex(index);
2141 const ElementRegion *ER = MRMgr.getElementRegion(ElemType, Idx, R, Ctx);
2143 if (ElemType->isArrayType())
2144 NewB = bindArray(NewB, ER, *VI);
2145 else if (ElemType->isStructureOrClassType())
2146 NewB = bindStruct(NewB, ER, *VI);
2148 NewB = bind(NewB, loc::MemRegionVal(ER), *VI);
2153 Optional<RegionBindingsRef>
2154 RegionStoreManager::tryBindSmallStruct(RegionBindingsConstRef B,
2155 const TypedValueRegion *R,
2156 const RecordDecl *RD,
2157 nonloc::LazyCompoundVal LCV) {
2160 if (const CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(RD))
2161 if (Class->getNumBases() != 0 || Class->getNumVBases() != 0)
2164 for (const auto *FD : RD->fields()) {
2165 if (FD->isUnnamedBitfield())
2168 // If there are too many fields, or if any of the fields are aggregates,
2169 // just use the LCV as a default binding.
2170 if (Fields.size() == SmallStructLimit)
2173 QualType Ty = FD->getType();
2174 if (!(Ty->isScalarType() || Ty->isReferenceType()))
2177 Fields.push_back(FD);
2180 RegionBindingsRef NewB = B;
2182 for (FieldVector::iterator I = Fields.begin(), E = Fields.end(); I != E; ++I){
2183 const FieldRegion *SourceFR = MRMgr.getFieldRegion(*I, LCV.getRegion());
2184 SVal V = getBindingForField(getRegionBindings(LCV.getStore()), SourceFR);
2186 const FieldRegion *DestFR = MRMgr.getFieldRegion(*I, R);
2187 NewB = bind(NewB, loc::MemRegionVal(DestFR), V);
2193 RegionBindingsRef RegionStoreManager::bindStruct(RegionBindingsConstRef B,
2194 const TypedValueRegion* R,
2196 if (!Features.supportsFields())
2199 QualType T = R->getValueType();
2200 assert(T->isStructureOrClassType());
2202 const RecordType* RT = T->getAs<RecordType>();
2203 const RecordDecl *RD = RT->getDecl();
2205 if (!RD->isCompleteDefinition())
2208 // Handle lazy compound values and symbolic values.
2209 if (Optional<nonloc::LazyCompoundVal> LCV =
2210 V.getAs<nonloc::LazyCompoundVal>()) {
2211 if (Optional<RegionBindingsRef> NewB = tryBindSmallStruct(B, R, RD, *LCV))
2213 return bindAggregate(B, R, V);
2215 if (V.getAs<nonloc::SymbolVal>())
2216 return bindAggregate(B, R, V);
2218 // We may get non-CompoundVal accidentally due to imprecise cast logic or
2219 // that we are binding symbolic struct value. Kill the field values, and if
2220 // the value is symbolic go and bind it as a "default" binding.
2221 if (V.isUnknown() || !V.getAs<nonloc::CompoundVal>())
2222 return bindAggregate(B, R, UnknownVal());
2224 const nonloc::CompoundVal& CV = V.castAs<nonloc::CompoundVal>();
2225 nonloc::CompoundVal::iterator VI = CV.begin(), VE = CV.end();
2227 RecordDecl::field_iterator FI, FE;
2228 RegionBindingsRef NewB(B);
2230 for (FI = RD->field_begin(), FE = RD->field_end(); FI != FE; ++FI) {
2235 // Skip any unnamed bitfields to stay in sync with the initializers.
2236 if (FI->isUnnamedBitfield())
2239 QualType FTy = FI->getType();
2240 const FieldRegion* FR = MRMgr.getFieldRegion(*FI, R);
2242 if (FTy->isArrayType())
2243 NewB = bindArray(NewB, FR, *VI);
2244 else if (FTy->isStructureOrClassType())
2245 NewB = bindStruct(NewB, FR, *VI);
2247 NewB = bind(NewB, loc::MemRegionVal(FR), *VI);
2251 // There may be fewer values in the initialize list than the fields of struct.
2253 NewB = NewB.addBinding(R, BindingKey::Default,
2254 svalBuilder.makeIntVal(0, false));
2261 RegionStoreManager::bindAggregate(RegionBindingsConstRef B,
2262 const TypedRegion *R,
2264 // Remove the old bindings, using 'R' as the root of all regions
2265 // we will invalidate. Then add the new binding.
2266 return removeSubRegionBindings(B, R).addBinding(R, BindingKey::Default, Val);
2269 //===----------------------------------------------------------------------===//
2271 //===----------------------------------------------------------------------===//
2274 class removeDeadBindingsWorker :
2275 public ClusterAnalysis<removeDeadBindingsWorker> {
2276 SmallVector<const SymbolicRegion*, 12> Postponed;
2277 SymbolReaper &SymReaper;
2278 const StackFrameContext *CurrentLCtx;
2281 removeDeadBindingsWorker(RegionStoreManager &rm,
2282 ProgramStateManager &stateMgr,
2283 RegionBindingsRef b, SymbolReaper &symReaper,
2284 const StackFrameContext *LCtx)
2285 : ClusterAnalysis<removeDeadBindingsWorker>(rm, stateMgr, b),
2286 SymReaper(symReaper), CurrentLCtx(LCtx) {}
2288 // Called by ClusterAnalysis.
2289 void VisitAddedToCluster(const MemRegion *baseR, const ClusterBindings &C);
2290 void VisitCluster(const MemRegion *baseR, const ClusterBindings *C);
2291 using ClusterAnalysis<removeDeadBindingsWorker>::VisitCluster;
2293 using ClusterAnalysis::AddToWorkList;
2295 bool AddToWorkList(const MemRegion *R);
2297 bool UpdatePostponed();
2298 void VisitBinding(SVal V);
2302 bool removeDeadBindingsWorker::AddToWorkList(const MemRegion *R) {
2303 const MemRegion *BaseR = R->getBaseRegion();
2304 return AddToWorkList(WorkListElement(BaseR), getCluster(BaseR));
2307 void removeDeadBindingsWorker::VisitAddedToCluster(const MemRegion *baseR,
2308 const ClusterBindings &C) {
2310 if (const VarRegion *VR = dyn_cast<VarRegion>(baseR)) {
2311 if (SymReaper.isLive(VR))
2312 AddToWorkList(baseR, &C);
2317 if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(baseR)) {
2318 if (SymReaper.isLive(SR->getSymbol()))
2319 AddToWorkList(SR, &C);
2321 Postponed.push_back(SR);
2326 if (isa<NonStaticGlobalSpaceRegion>(baseR)) {
2327 AddToWorkList(baseR, &C);
2331 // CXXThisRegion in the current or parent location context is live.
2332 if (const CXXThisRegion *TR = dyn_cast<CXXThisRegion>(baseR)) {
2333 const StackArgumentsSpaceRegion *StackReg =
2334 cast<StackArgumentsSpaceRegion>(TR->getSuperRegion());
2335 const StackFrameContext *RegCtx = StackReg->getStackFrame();
2337 (RegCtx == CurrentLCtx || RegCtx->isParentOf(CurrentLCtx)))
2338 AddToWorkList(TR, &C);
2342 void removeDeadBindingsWorker::VisitCluster(const MemRegion *baseR,
2343 const ClusterBindings *C) {
2347 // Mark the symbol for any SymbolicRegion with live bindings as live itself.
2348 // This means we should continue to track that symbol.
2349 if (const SymbolicRegion *SymR = dyn_cast<SymbolicRegion>(baseR))
2350 SymReaper.markLive(SymR->getSymbol());
2352 for (ClusterBindings::iterator I = C->begin(), E = C->end(); I != E; ++I) {
2353 // Element index of a binding key is live.
2354 SymReaper.markElementIndicesLive(I.getKey().getRegion());
2356 VisitBinding(I.getData());
2360 void removeDeadBindingsWorker::VisitBinding(SVal V) {
2361 // Is it a LazyCompoundVal? All referenced regions are live as well.
2362 if (Optional<nonloc::LazyCompoundVal> LCS =
2363 V.getAs<nonloc::LazyCompoundVal>()) {
2365 const RegionStoreManager::SValListTy &Vals = RM.getInterestingValues(*LCS);
2367 for (RegionStoreManager::SValListTy::const_iterator I = Vals.begin(),
2375 // If V is a region, then add it to the worklist.
2376 if (const MemRegion *R = V.getAsRegion()) {
2378 SymReaper.markLive(R);
2380 // All regions captured by a block are also live.
2381 if (const BlockDataRegion *BR = dyn_cast<BlockDataRegion>(R)) {
2382 BlockDataRegion::referenced_vars_iterator I = BR->referenced_vars_begin(),
2383 E = BR->referenced_vars_end();
2384 for ( ; I != E; ++I)
2385 AddToWorkList(I.getCapturedRegion());
2390 // Update the set of live symbols.
2391 for (SymExpr::symbol_iterator SI = V.symbol_begin(), SE = V.symbol_end();
2393 SymReaper.markLive(*SI);
2396 bool removeDeadBindingsWorker::UpdatePostponed() {
2397 // See if any postponed SymbolicRegions are actually live now, after
2398 // having done a scan.
2399 bool changed = false;
2401 for (SmallVectorImpl<const SymbolicRegion*>::iterator
2402 I = Postponed.begin(), E = Postponed.end() ; I != E ; ++I) {
2403 if (const SymbolicRegion *SR = *I) {
2404 if (SymReaper.isLive(SR->getSymbol())) {
2405 changed |= AddToWorkList(SR);
2414 StoreRef RegionStoreManager::removeDeadBindings(Store store,
2415 const StackFrameContext *LCtx,
2416 SymbolReaper& SymReaper) {
2417 RegionBindingsRef B = getRegionBindings(store);
2418 removeDeadBindingsWorker W(*this, StateMgr, B, SymReaper, LCtx);
2419 W.GenerateClusters();
2421 // Enqueue the region roots onto the worklist.
2422 for (SymbolReaper::region_iterator I = SymReaper.region_begin(),
2423 E = SymReaper.region_end(); I != E; ++I) {
2424 W.AddToWorkList(*I);
2427 do W.RunWorkList(); while (W.UpdatePostponed());
2429 // We have now scanned the store, marking reachable regions and symbols
2430 // as live. We now remove all the regions that are dead from the store
2431 // as well as update DSymbols with the set symbols that are now dead.
2432 for (RegionBindingsRef::iterator I = B.begin(), E = B.end(); I != E; ++I) {
2433 const MemRegion *Base = I.getKey();
2435 // If the cluster has been visited, we know the region has been marked.
2436 if (W.isVisited(Base))
2439 // Remove the dead entry.
2442 if (const SymbolicRegion *SymR = dyn_cast<SymbolicRegion>(Base))
2443 SymReaper.maybeDead(SymR->getSymbol());
2445 // Mark all non-live symbols that this binding references as dead.
2446 const ClusterBindings &Cluster = I.getData();
2447 for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end();
2449 SVal X = CI.getData();
2450 SymExpr::symbol_iterator SI = X.symbol_begin(), SE = X.symbol_end();
2451 for (; SI != SE; ++SI)
2452 SymReaper.maybeDead(*SI);
2456 return StoreRef(B.asStore(), *this);
2459 //===----------------------------------------------------------------------===//
2461 //===----------------------------------------------------------------------===//
2463 void RegionStoreManager::print(Store store, raw_ostream &OS,
2464 const char* nl, const char *sep) {
2465 RegionBindingsRef B = getRegionBindings(store);
2466 OS << "Store (direct and default bindings), "