| //== RegionStore.cpp - Field-sensitive store model --------------*- C++ -*--==// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file defines a basic region store model. In this model, we do have field |
| // sensitivity. But we assume nothing about the heap shape. So recursive data |
| // structures are largely ignored. Basically we do 1-limiting analysis. |
| // Parameter pointers are assumed with no aliasing. Pointee objects of |
| // parameters are created lazily. |
| // |
| //===----------------------------------------------------------------------===// |
| #include "clang/AST/CharUnits.h" |
| #include "clang/AST/DeclCXX.h" |
| #include "clang/AST/ExprCXX.h" |
| #include "clang/AST/CXXInheritance.h" |
| #include "clang/Analysis/Analyses/LiveVariables.h" |
| #include "clang/Analysis/AnalysisContext.h" |
| #include "clang/Basic/TargetInfo.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h" |
| #include "llvm/ADT/ImmutableList.h" |
| #include "llvm/ADT/ImmutableMap.h" |
| #include "llvm/ADT/Optional.h" |
| #include "llvm/Support/raw_ostream.h" |
| |
| using namespace clang; |
| using namespace ento; |
| using llvm::Optional; |
| |
| //===----------------------------------------------------------------------===// |
| // Representation of binding keys. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| class BindingKey { |
| public: |
| enum Kind { Default = 0x0, Direct = 0x1 }; |
| private: |
| enum { Symbolic = 0x2 }; |
| |
| llvm::PointerIntPair<const MemRegion *, 2> P; |
| uint64_t Data; |
| |
| explicit BindingKey(const MemRegion *r, const MemRegion *Base, Kind k) |
| : P(r, k | Symbolic), Data(reinterpret_cast<uintptr_t>(Base)) { |
| assert(r && Base && "Must have known regions."); |
| assert(getConcreteOffsetRegion() == Base && "Failed to store base region"); |
| } |
| explicit BindingKey(const MemRegion *r, uint64_t offset, Kind k) |
| : P(r, k), Data(offset) { |
| assert(r && "Must have known regions."); |
| assert(getOffset() == offset && "Failed to store offset"); |
| assert((r == r->getBaseRegion() || isa<ObjCIvarRegion>(r)) && "Not a base"); |
| } |
| public: |
| |
| bool isDirect() const { return P.getInt() & Direct; } |
| bool hasSymbolicOffset() const { return P.getInt() & Symbolic; } |
| |
| const MemRegion *getRegion() const { return P.getPointer(); } |
| uint64_t getOffset() const { |
| assert(!hasSymbolicOffset()); |
| return Data; |
| } |
| |
| const MemRegion *getConcreteOffsetRegion() const { |
| assert(hasSymbolicOffset()); |
| return reinterpret_cast<const MemRegion *>(static_cast<uintptr_t>(Data)); |
| } |
| |
| const MemRegion *getBaseRegion() const { |
| if (hasSymbolicOffset()) |
| return getConcreteOffsetRegion()->getBaseRegion(); |
| return getRegion()->getBaseRegion(); |
| } |
| |
| void Profile(llvm::FoldingSetNodeID& ID) const { |
| ID.AddPointer(P.getOpaqueValue()); |
| ID.AddInteger(Data); |
| } |
| |
| static BindingKey Make(const MemRegion *R, Kind k); |
| |
| bool operator<(const BindingKey &X) const { |
| if (P.getOpaqueValue() < X.P.getOpaqueValue()) |
| return true; |
| if (P.getOpaqueValue() > X.P.getOpaqueValue()) |
| return false; |
| return Data < X.Data; |
| } |
| |
| bool operator==(const BindingKey &X) const { |
| return P.getOpaqueValue() == X.P.getOpaqueValue() && |
| Data == X.Data; |
| } |
| |
| LLVM_ATTRIBUTE_USED void dump() const; |
| }; |
| } // end anonymous namespace |
| |
| BindingKey BindingKey::Make(const MemRegion *R, Kind k) { |
| const RegionOffset &RO = R->getAsOffset(); |
| if (RO.hasSymbolicOffset()) |
| return BindingKey(R, RO.getRegion(), k); |
| |
| return BindingKey(RO.getRegion(), RO.getOffset(), k); |
| } |
| |
| namespace llvm { |
| static inline |
| raw_ostream &operator<<(raw_ostream &os, BindingKey K) { |
| os << '(' << K.getRegion(); |
| if (!K.hasSymbolicOffset()) |
| os << ',' << K.getOffset(); |
| os << ',' << (K.isDirect() ? "direct" : "default") |
| << ')'; |
| return os; |
| } |
| } // end llvm namespace |
| |
| void BindingKey::dump() const { |
| llvm::errs() << *this; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Actual Store type. |
| //===----------------------------------------------------------------------===// |
| |
| typedef llvm::ImmutableMap<BindingKey, SVal> ClusterBindings; |
| typedef llvm::ImmutableMap<const MemRegion *, ClusterBindings> RegionBindings; |
| |
| //===----------------------------------------------------------------------===// |
| // Fine-grained control of RegionStoreManager. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| struct minimal_features_tag {}; |
| struct maximal_features_tag {}; |
| |
| class RegionStoreFeatures { |
| bool SupportsFields; |
| public: |
| RegionStoreFeatures(minimal_features_tag) : |
| SupportsFields(false) {} |
| |
| RegionStoreFeatures(maximal_features_tag) : |
| SupportsFields(true) {} |
| |
| void enableFields(bool t) { SupportsFields = t; } |
| |
| bool supportsFields() const { return SupportsFields; } |
| }; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Main RegionStore logic. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| |
| class RegionStoreManager : public StoreManager { |
| const RegionStoreFeatures Features; |
| RegionBindings::Factory RBFactory; |
| ClusterBindings::Factory CBFactory; |
| |
| public: |
| RegionStoreManager(ProgramStateManager& mgr, const RegionStoreFeatures &f) |
| : StoreManager(mgr), Features(f), |
| RBFactory(mgr.getAllocator()), CBFactory(mgr.getAllocator()) {} |
| |
| Optional<SVal> getDirectBinding(RegionBindings B, const MemRegion *R); |
| /// getDefaultBinding - Returns an SVal* representing an optional default |
| /// binding associated with a region and its subregions. |
| Optional<SVal> getDefaultBinding(RegionBindings B, const MemRegion *R); |
| |
| /// setImplicitDefaultValue - Set the default binding for the provided |
| /// MemRegion to the value implicitly defined for compound literals when |
| /// the value is not specified. |
| StoreRef setImplicitDefaultValue(Store store, const MemRegion *R, QualType T); |
| |
| /// ArrayToPointer - Emulates the "decay" of an array to a pointer |
| /// type. 'Array' represents the lvalue of the array being decayed |
| /// to a pointer, and the returned SVal represents the decayed |
| /// version of that lvalue (i.e., a pointer to the first element of |
| /// the array). This is called by ExprEngine when evaluating |
| /// casts from arrays to pointers. |
| SVal ArrayToPointer(Loc Array); |
| |
| /// For DerivedToBase casts, create a CXXBaseObjectRegion and return it. |
| virtual SVal evalDerivedToBase(SVal derived, QualType basePtrType); |
| |
| /// \brief Evaluates C++ dynamic_cast cast. |
| /// The callback may result in the following 3 scenarios: |
| /// - Successful cast (ex: derived is subclass of base). |
| /// - Failed cast (ex: derived is definitely not a subclass of base). |
| /// - We don't know (base is a symbolic region and we don't have |
| /// enough info to determine if the cast will succeed at run time). |
| /// The function returns an SVal representing the derived class; it's |
| /// valid only if Failed flag is set to false. |
| virtual SVal evalDynamicCast(SVal base, QualType derivedPtrType,bool &Failed); |
| |
| StoreRef getInitialStore(const LocationContext *InitLoc) { |
| return StoreRef(RBFactory.getEmptyMap().getRootWithoutRetain(), *this); |
| } |
| |
| //===-------------------------------------------------------------------===// |
| // Binding values to regions. |
| //===-------------------------------------------------------------------===// |
| RegionBindings invalidateGlobalRegion(MemRegion::Kind K, |
| const Expr *Ex, |
| unsigned Count, |
| const LocationContext *LCtx, |
| RegionBindings B, |
| InvalidatedRegions *Invalidated); |
| |
| StoreRef invalidateRegions(Store store, ArrayRef<const MemRegion *> Regions, |
| const Expr *E, unsigned Count, |
| const LocationContext *LCtx, |
| InvalidatedSymbols &IS, |
| const CallEvent *Call, |
| InvalidatedRegions *Invalidated); |
| |
| bool scanReachableSymbols(Store S, const MemRegion *R, |
| ScanReachableSymbols &Callbacks); |
| |
| public: // Made public for helper classes. |
| |
| RegionBindings removeSubRegionBindings(RegionBindings B, const SubRegion *R); |
| |
| RegionBindings addBinding(RegionBindings B, BindingKey K, SVal V); |
| |
| RegionBindings addBinding(RegionBindings B, const MemRegion *R, |
| BindingKey::Kind k, SVal V); |
| |
| const SVal *lookup(RegionBindings B, BindingKey K); |
| const SVal *lookup(RegionBindings B, const MemRegion *R, BindingKey::Kind k); |
| |
| RegionBindings removeBinding(RegionBindings B, BindingKey K); |
| RegionBindings removeBinding(RegionBindings B, const MemRegion *R, |
| BindingKey::Kind k); |
| |
| RegionBindings removeBinding(RegionBindings B, const MemRegion *R) { |
| return removeBinding(removeBinding(B, R, BindingKey::Direct), R, |
| BindingKey::Default); |
| } |
| |
| RegionBindings removeCluster(RegionBindings B, const MemRegion *R); |
| |
| public: // Part of public interface to class. |
| |
| StoreRef Bind(Store store, Loc LV, SVal V); |
| |
| // BindDefault is only used to initialize a region with a default value. |
| StoreRef BindDefault(Store store, const MemRegion *R, SVal V) { |
| RegionBindings B = GetRegionBindings(store); |
| assert(!lookup(B, R, BindingKey::Default)); |
| assert(!lookup(B, R, BindingKey::Direct)); |
| return StoreRef(addBinding(B, R, BindingKey::Default, V) |
| .getRootWithoutRetain(), *this); |
| } |
| |
| /// \brief Create a new store that binds a value to a compound literal. |
| /// |
| /// \param ST The original store whose bindings are the basis for the new |
| /// store. |
| /// |
| /// \param CL The compound literal to bind (the binding key). |
| /// |
| /// \param LC The LocationContext for the binding. |
| /// |
| /// \param V The value to bind to the compound literal. |
| StoreRef bindCompoundLiteral(Store ST, |
| const CompoundLiteralExpr *CL, |
| const LocationContext *LC, SVal V); |
| |
| /// BindStruct - Bind a compound value to a structure. |
| StoreRef BindStruct(Store store, const TypedValueRegion* R, SVal V); |
| |
| /// BindVector - Bind a compound value to a vector. |
| StoreRef BindVector(Store store, const TypedValueRegion* R, SVal V); |
| |
| StoreRef BindArray(Store store, const TypedValueRegion* R, SVal V); |
| |
| /// Clears out all bindings in the given region and assigns a new value |
| /// as a Default binding. |
| StoreRef BindAggregate(Store store, const TypedRegion *R, SVal DefaultVal); |
| |
| /// \brief Create a new store with the specified binding removed. |
| /// \param ST the original store, that is the basis for the new store. |
| /// \param L the location whose binding should be removed. |
| StoreRef killBinding(Store ST, Loc L); |
| |
| void incrementReferenceCount(Store store) { |
| GetRegionBindings(store).manualRetain(); |
| } |
| |
| /// If the StoreManager supports it, decrement the reference count of |
| /// the specified Store object. If the reference count hits 0, the memory |
| /// associated with the object is recycled. |
| void decrementReferenceCount(Store store) { |
| GetRegionBindings(store).manualRelease(); |
| } |
| |
| bool includedInBindings(Store store, const MemRegion *region) const; |
| |
| /// \brief Return the value bound to specified location in a given state. |
| /// |
| /// The high level logic for this method is this: |
| /// getBinding (L) |
| /// if L has binding |
| /// return L's binding |
| /// else if L is in killset |
| /// return unknown |
| /// else |
| /// if L is on stack or heap |
| /// return undefined |
| /// else |
| /// return symbolic |
| SVal getBinding(Store store, Loc L, QualType T = QualType()); |
| |
| SVal getBindingForElement(Store store, const ElementRegion *R); |
| |
| SVal getBindingForField(Store store, const FieldRegion *R); |
| |
| SVal getBindingForObjCIvar(Store store, const ObjCIvarRegion *R); |
| |
| SVal getBindingForVar(Store store, const VarRegion *R); |
| |
| SVal getBindingForLazySymbol(const TypedValueRegion *R); |
| |
| SVal getBindingForFieldOrElementCommon(Store store, const TypedValueRegion *R, |
| QualType Ty, const MemRegion *superR); |
| |
| SVal getLazyBinding(const MemRegion *lazyBindingRegion, |
| Store lazyBindingStore); |
| |
| /// Get bindings for the values in a struct and return a CompoundVal, used |
| /// when doing struct copy: |
| /// struct s x, y; |
| /// x = y; |
| /// y's value is retrieved by this method. |
| SVal getBindingForStruct(Store store, const TypedValueRegion* R); |
| |
| SVal getBindingForArray(Store store, const TypedValueRegion* R); |
| |
| /// Used to lazily generate derived symbols for bindings that are defined |
| /// implicitly by default bindings in a super region. |
| Optional<SVal> getBindingForDerivedDefaultValue(RegionBindings B, |
| const MemRegion *superR, |
| const TypedValueRegion *R, |
| QualType Ty); |
| |
| /// Get the state and region whose binding this region R corresponds to. |
| std::pair<Store, const MemRegion*> |
| GetLazyBinding(RegionBindings B, const MemRegion *R, |
| const MemRegion *originalRegion, |
| bool includeSuffix = false); |
| |
| //===------------------------------------------------------------------===// |
| // State pruning. |
| //===------------------------------------------------------------------===// |
| |
| /// removeDeadBindings - Scans the RegionStore of 'state' for dead values. |
| /// It returns a new Store with these values removed. |
| StoreRef removeDeadBindings(Store store, const StackFrameContext *LCtx, |
| SymbolReaper& SymReaper); |
| |
| //===------------------------------------------------------------------===// |
| // Region "extents". |
| //===------------------------------------------------------------------===// |
| |
| // FIXME: This method will soon be eliminated; see the note in Store.h. |
| DefinedOrUnknownSVal getSizeInElements(ProgramStateRef state, |
| const MemRegion* R, QualType EleTy); |
| |
| //===------------------------------------------------------------------===// |
| // Utility methods. |
| //===------------------------------------------------------------------===// |
| |
| static inline RegionBindings GetRegionBindings(Store store) { |
| return RegionBindings(static_cast<const RegionBindings::TreeTy*>(store)); |
| } |
| |
| void print(Store store, raw_ostream &Out, const char* nl, |
| const char *sep); |
| |
| void iterBindings(Store store, BindingsHandler& f) { |
| RegionBindings B = GetRegionBindings(store); |
| for (RegionBindings::iterator I = B.begin(), E = B.end(); I != E; ++I) { |
| const ClusterBindings &Cluster = I.getData(); |
| for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end(); |
| CI != CE; ++CI) { |
| const BindingKey &K = CI.getKey(); |
| if (!K.isDirect()) |
| continue; |
| if (const SubRegion *R = dyn_cast<SubRegion>(K.getRegion())) { |
| // FIXME: Possibly incorporate the offset? |
| if (!f.HandleBinding(*this, store, R, CI.getData())) |
| return; |
| } |
| } |
| } |
| } |
| }; |
| |
| } // end anonymous namespace |
| |
| //===----------------------------------------------------------------------===// |
| // RegionStore creation. |
| //===----------------------------------------------------------------------===// |
| |
| StoreManager *ento::CreateRegionStoreManager(ProgramStateManager& StMgr) { |
| RegionStoreFeatures F = maximal_features_tag(); |
| return new RegionStoreManager(StMgr, F); |
| } |
| |
| StoreManager * |
| ento::CreateFieldsOnlyRegionStoreManager(ProgramStateManager &StMgr) { |
| RegionStoreFeatures F = minimal_features_tag(); |
| F.enableFields(true); |
| return new RegionStoreManager(StMgr, F); |
| } |
| |
| |
| //===----------------------------------------------------------------------===// |
| // Region Cluster analysis. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| template <typename DERIVED> |
| class ClusterAnalysis { |
| protected: |
| typedef llvm::DenseMap<const MemRegion *, const ClusterBindings *> ClusterMap; |
| typedef SmallVector<const MemRegion *, 10> WorkList; |
| |
| llvm::SmallPtrSet<const ClusterBindings *, 16> Visited; |
| |
| WorkList WL; |
| |
| RegionStoreManager &RM; |
| ASTContext &Ctx; |
| SValBuilder &svalBuilder; |
| |
| RegionBindings B; |
| |
| const bool includeGlobals; |
| |
| const ClusterBindings *getCluster(const MemRegion *R) { |
| return B.lookup(R); |
| } |
| |
| public: |
| ClusterAnalysis(RegionStoreManager &rm, ProgramStateManager &StateMgr, |
| RegionBindings b, const bool includeGlobals) |
| : RM(rm), Ctx(StateMgr.getContext()), |
| svalBuilder(StateMgr.getSValBuilder()), |
| B(b), includeGlobals(includeGlobals) {} |
| |
| RegionBindings getRegionBindings() const { return B; } |
| |
| bool isVisited(const MemRegion *R) { |
| return Visited.count(getCluster(R)); |
| } |
| |
| void GenerateClusters() { |
| // Scan the entire set of bindings and record the region clusters. |
| for (RegionBindings::iterator RI = B.begin(), RE = B.end(); RI != RE; ++RI){ |
| const MemRegion *Base = RI.getKey(); |
| |
| const ClusterBindings &Cluster = RI.getData(); |
| assert(!Cluster.isEmpty() && "Empty clusters should be removed"); |
| static_cast<DERIVED*>(this)->VisitAddedToCluster(Base, Cluster); |
| |
| if (includeGlobals) |
| if (isa<NonStaticGlobalSpaceRegion>(Base->getMemorySpace())) |
| AddToWorkList(Base, &Cluster); |
| } |
| } |
| |
| bool AddToWorkList(const MemRegion *R, const ClusterBindings *C) { |
| if (C && !Visited.insert(C)) |
| return false; |
| WL.push_back(R); |
| return true; |
| } |
| |
| bool AddToWorkList(const MemRegion *R) { |
| const MemRegion *baseR = R->getBaseRegion(); |
| return AddToWorkList(baseR, getCluster(baseR)); |
| } |
| |
| void RunWorkList() { |
| while (!WL.empty()) { |
| const MemRegion *baseR = WL.pop_back_val(); |
| |
| // First visit the cluster. |
| if (const ClusterBindings *Cluster = getCluster(baseR)) |
| static_cast<DERIVED*>(this)->VisitCluster(baseR, *Cluster); |
| |
| // Next, visit the base region. |
| static_cast<DERIVED*>(this)->VisitBaseRegion(baseR); |
| } |
| } |
| |
| public: |
| void VisitAddedToCluster(const MemRegion *baseR, const ClusterBindings &C) {} |
| void VisitCluster(const MemRegion *baseR, const ClusterBindings &C) {} |
| void VisitBaseRegion(const MemRegion *baseR) {} |
| }; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Binding invalidation. |
| //===----------------------------------------------------------------------===// |
| |
| bool RegionStoreManager::scanReachableSymbols(Store S, const MemRegion *R, |
| ScanReachableSymbols &Callbacks) { |
| assert(R == R->getBaseRegion() && "Should only be called for base regions"); |
| RegionBindings B = GetRegionBindings(S); |
| const ClusterBindings *Cluster = B.lookup(R); |
| |
| if (!Cluster) |
| return true; |
| |
| for (ClusterBindings::iterator RI = Cluster->begin(), RE = Cluster->end(); |
| RI != RE; ++RI) { |
| if (!Callbacks.scan(RI.getData())) |
| return false; |
| } |
| |
| return true; |
| } |
| |
| RegionBindings RegionStoreManager::removeSubRegionBindings(RegionBindings B, |
| const SubRegion *R) { |
| BindingKey SRKey = BindingKey::Make(R, BindingKey::Default); |
| const MemRegion *ClusterHead = SRKey.getBaseRegion(); |
| if (R == ClusterHead) { |
| // We can remove an entire cluster's bindings all in one go. |
| return RBFactory.remove(B, R); |
| } |
| |
| if (SRKey.hasSymbolicOffset()) { |
| const SubRegion *Base = cast<SubRegion>(SRKey.getConcreteOffsetRegion()); |
| B = removeSubRegionBindings(B, Base); |
| return addBinding(B, Base, BindingKey::Default, UnknownVal()); |
| } |
| |
| // This assumes the region being invalidated is char-aligned. This isn't |
| // true for bitfields, but since bitfields have no subregions they shouldn't |
| // be using this function anyway. |
| uint64_t Length = UINT64_MAX; |
| |
| SVal Extent = R->getExtent(svalBuilder); |
| if (nonloc::ConcreteInt *ExtentCI = dyn_cast<nonloc::ConcreteInt>(&Extent)) { |
| const llvm::APSInt &ExtentInt = ExtentCI->getValue(); |
| assert(ExtentInt.isNonNegative() || ExtentInt.isUnsigned()); |
| // Extents are in bytes but region offsets are in bits. Be careful! |
| Length = ExtentInt.getLimitedValue() * Ctx.getCharWidth(); |
| } |
| |
| const ClusterBindings *Cluster = B.lookup(ClusterHead); |
| if (!Cluster) |
| return B; |
| |
| ClusterBindings Result = *Cluster; |
| |
| // It is safe to iterate over the bindings as they are being changed |
| // because they are in an ImmutableMap. |
| for (ClusterBindings::iterator I = Cluster->begin(), E = Cluster->end(); |
| I != E; ++I) { |
| BindingKey NextKey = I.getKey(); |
| if (NextKey.getRegion() == SRKey.getRegion()) { |
| if (NextKey.getOffset() > SRKey.getOffset() && |
| NextKey.getOffset() - SRKey.getOffset() < Length) { |
| // Case 1: The next binding is inside the region we're invalidating. |
| // Remove it. |
| Result = CBFactory.remove(Result, NextKey); |
| } else if (NextKey.getOffset() == SRKey.getOffset()) { |
| // Case 2: The next binding is at the same offset as the region we're |
| // invalidating. In this case, we need to leave default bindings alone, |
| // since they may be providing a default value for a regions beyond what |
| // we're invalidating. |
| // FIXME: This is probably incorrect; consider invalidating an outer |
| // struct whose first field is bound to a LazyCompoundVal. |
| if (NextKey.isDirect()) |
| Result = CBFactory.remove(Result, NextKey); |
| } |
| } else if (NextKey.hasSymbolicOffset()) { |
| const MemRegion *Base = NextKey.getConcreteOffsetRegion(); |
| if (R->isSubRegionOf(Base)) { |
| // Case 3: The next key is symbolic and we just changed something within |
| // its concrete region. We don't know if the binding is still valid, so |
| // we'll be conservative and remove it. |
| if (NextKey.isDirect()) |
| Result = CBFactory.remove(Result, NextKey); |
| } else if (const SubRegion *BaseSR = dyn_cast<SubRegion>(Base)) { |
| // Case 4: The next key is symbolic, but we changed a known |
| // super-region. In this case the binding is certainly no longer valid. |
| if (R == Base || BaseSR->isSubRegionOf(R)) |
| Result = CBFactory.remove(Result, NextKey); |
| } |
| } |
| } |
| |
| if (Result.isEmpty()) |
| return RBFactory.remove(B, ClusterHead); |
| return RBFactory.add(B, ClusterHead, Result); |
| } |
| |
| namespace { |
| class invalidateRegionsWorker : public ClusterAnalysis<invalidateRegionsWorker> |
| { |
| const Expr *Ex; |
| unsigned Count; |
| const LocationContext *LCtx; |
| StoreManager::InvalidatedSymbols &IS; |
| StoreManager::InvalidatedRegions *Regions; |
| public: |
| invalidateRegionsWorker(RegionStoreManager &rm, |
| ProgramStateManager &stateMgr, |
| RegionBindings b, |
| const Expr *ex, unsigned count, |
| const LocationContext *lctx, |
| StoreManager::InvalidatedSymbols &is, |
| StoreManager::InvalidatedRegions *r, |
| bool includeGlobals) |
| : ClusterAnalysis<invalidateRegionsWorker>(rm, stateMgr, b, includeGlobals), |
| Ex(ex), Count(count), LCtx(lctx), IS(is), Regions(r) {} |
| |
| void VisitCluster(const MemRegion *baseR, const ClusterBindings &C); |
| void VisitBaseRegion(const MemRegion *baseR); |
| |
| private: |
| void VisitBinding(SVal V); |
| }; |
| } |
| |
| void invalidateRegionsWorker::VisitBinding(SVal V) { |
| // A symbol? Mark it touched by the invalidation. |
| if (SymbolRef Sym = V.getAsSymbol()) |
| IS.insert(Sym); |
| |
| if (const MemRegion *R = V.getAsRegion()) { |
| AddToWorkList(R); |
| return; |
| } |
| |
| // Is it a LazyCompoundVal? All references get invalidated as well. |
| if (const nonloc::LazyCompoundVal *LCS = |
| dyn_cast<nonloc::LazyCompoundVal>(&V)) { |
| |
| const MemRegion *LazyR = LCS->getRegion(); |
| RegionBindings B = RegionStoreManager::GetRegionBindings(LCS->getStore()); |
| |
| // FIXME: This should not have to walk all bindings in the old store. |
| for (RegionBindings::iterator RI = B.begin(), RE = B.end(); RI != RE; ++RI){ |
| const ClusterBindings &Cluster = RI.getData(); |
| for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end(); |
| CI != CE; ++CI) { |
| BindingKey K = CI.getKey(); |
| if (const SubRegion *BaseR = dyn_cast<SubRegion>(K.getRegion())) { |
| if (BaseR == LazyR) |
| VisitBinding(CI.getData()); |
| else if (K.hasSymbolicOffset() && BaseR->isSubRegionOf(LazyR)) |
| VisitBinding(CI.getData()); |
| } |
| } |
| } |
| |
| return; |
| } |
| } |
| |
| void invalidateRegionsWorker::VisitCluster(const MemRegion *BaseR, |
| const ClusterBindings &C) { |
| for (ClusterBindings::iterator I = C.begin(), E = C.end(); I != E; ++I) |
| VisitBinding(I.getData()); |
| |
| B = RM.removeCluster(B, BaseR); |
| } |
| |
| void invalidateRegionsWorker::VisitBaseRegion(const MemRegion *baseR) { |
| // Symbolic region? Mark that symbol touched by the invalidation. |
| if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(baseR)) |
| IS.insert(SR->getSymbol()); |
| |
| // BlockDataRegion? If so, invalidate captured variables that are passed |
| // by reference. |
| if (const BlockDataRegion *BR = dyn_cast<BlockDataRegion>(baseR)) { |
| for (BlockDataRegion::referenced_vars_iterator |
| BI = BR->referenced_vars_begin(), BE = BR->referenced_vars_end() ; |
| BI != BE; ++BI) { |
| const VarRegion *VR = *BI; |
| const VarDecl *VD = VR->getDecl(); |
| if (VD->getAttr<BlocksAttr>() || !VD->hasLocalStorage()) { |
| AddToWorkList(VR); |
| } |
| else if (Loc::isLocType(VR->getValueType())) { |
| // Map the current bindings to a Store to retrieve the value |
| // of the binding. If that binding itself is a region, we should |
| // invalidate that region. This is because a block may capture |
| // a pointer value, but the thing pointed by that pointer may |
| // get invalidated. |
| Store store = B.getRootWithoutRetain(); |
| SVal V = RM.getBinding(store, loc::MemRegionVal(VR)); |
| if (const Loc *L = dyn_cast<Loc>(&V)) { |
| if (const MemRegion *LR = L->getAsRegion()) |
| AddToWorkList(LR); |
| } |
| } |
| } |
| return; |
| } |
| |
| // Otherwise, we have a normal data region. Record that we touched the region. |
| if (Regions) |
| Regions->push_back(baseR); |
| |
| if (isa<AllocaRegion>(baseR) || isa<SymbolicRegion>(baseR)) { |
| // Invalidate the region by setting its default value to |
| // conjured symbol. The type of the symbol is irrelavant. |
| DefinedOrUnknownSVal V = |
| svalBuilder.conjureSymbolVal(baseR, Ex, LCtx, Ctx.IntTy, Count); |
| B = RM.addBinding(B, baseR, BindingKey::Default, V); |
| return; |
| } |
| |
| if (!baseR->isBoundable()) |
| return; |
| |
| const TypedValueRegion *TR = cast<TypedValueRegion>(baseR); |
| QualType T = TR->getValueType(); |
| |
| // Invalidate the binding. |
| if (T->isStructureOrClassType()) { |
| // Invalidate the region by setting its default value to |
| // conjured symbol. The type of the symbol is irrelavant. |
| DefinedOrUnknownSVal V = svalBuilder.conjureSymbolVal(baseR, Ex, LCtx, |
| Ctx.IntTy, Count); |
| B = RM.addBinding(B, baseR, BindingKey::Default, V); |
| return; |
| } |
| |
| if (const ArrayType *AT = Ctx.getAsArrayType(T)) { |
| // Set the default value of the array to conjured symbol. |
| DefinedOrUnknownSVal V = |
| svalBuilder.conjureSymbolVal(baseR, Ex, LCtx, |
| AT->getElementType(), Count); |
| B = RM.addBinding(B, baseR, BindingKey::Default, V); |
| return; |
| } |
| |
| if (includeGlobals && |
| isa<NonStaticGlobalSpaceRegion>(baseR->getMemorySpace())) { |
| // If the region is a global and we are invalidating all globals, |
| // just erase the entry. This causes all globals to be lazily |
| // symbolicated from the same base symbol. |
| B = RM.removeBinding(B, baseR); |
| return; |
| } |
| |
| |
| DefinedOrUnknownSVal V = svalBuilder.conjureSymbolVal(baseR, Ex, LCtx, |
| T,Count); |
| assert(SymbolManager::canSymbolicate(T) || V.isUnknown()); |
| B = RM.addBinding(B, baseR, BindingKey::Direct, V); |
| } |
| |
| RegionBindings RegionStoreManager::invalidateGlobalRegion(MemRegion::Kind K, |
| const Expr *Ex, |
| unsigned Count, |
| const LocationContext *LCtx, |
| RegionBindings B, |
| InvalidatedRegions *Invalidated) { |
| // Bind the globals memory space to a new symbol that we will use to derive |
| // the bindings for all globals. |
| const GlobalsSpaceRegion *GS = MRMgr.getGlobalsRegion(K); |
| SVal V = svalBuilder.conjureSymbolVal(/* SymbolTag = */ (void*) GS, Ex, LCtx, |
| /* type does not matter */ Ctx.IntTy, |
| Count); |
| |
| B = removeBinding(B, GS); |
| B = addBinding(B, BindingKey::Make(GS, BindingKey::Default), V); |
| |
| // Even if there are no bindings in the global scope, we still need to |
| // record that we touched it. |
| if (Invalidated) |
| Invalidated->push_back(GS); |
| |
| return B; |
| } |
| |
| StoreRef RegionStoreManager::invalidateRegions(Store store, |
| ArrayRef<const MemRegion *> Regions, |
| const Expr *Ex, unsigned Count, |
| const LocationContext *LCtx, |
| InvalidatedSymbols &IS, |
| const CallEvent *Call, |
| InvalidatedRegions *Invalidated) { |
| invalidateRegionsWorker W(*this, StateMgr, |
| RegionStoreManager::GetRegionBindings(store), |
| Ex, Count, LCtx, IS, Invalidated, false); |
| |
| // Scan the bindings and generate the clusters. |
| W.GenerateClusters(); |
| |
| // Add the regions to the worklist. |
| for (ArrayRef<const MemRegion *>::iterator |
| I = Regions.begin(), E = Regions.end(); I != E; ++I) |
| W.AddToWorkList(*I); |
| |
| W.RunWorkList(); |
| |
| // Return the new bindings. |
| RegionBindings B = W.getRegionBindings(); |
| |
| // For all globals which are not static nor immutable: determine which global |
| // regions should be invalidated and invalidate them. |
| // TODO: This could possibly be more precise with modules. |
| // |
| // System calls invalidate only system globals. |
| if (Call && Call->isInSystemHeader()) { |
| B = invalidateGlobalRegion(MemRegion::GlobalSystemSpaceRegionKind, |
| Ex, Count, LCtx, B, Invalidated); |
| // Internal calls might invalidate both system and internal globals. |
| } else { |
| B = invalidateGlobalRegion(MemRegion::GlobalSystemSpaceRegionKind, |
| Ex, Count, LCtx, B, Invalidated); |
| B = invalidateGlobalRegion(MemRegion::GlobalInternalSpaceRegionKind, |
| Ex, Count, LCtx, B, Invalidated); |
| } |
| |
| return StoreRef(B.getRootWithoutRetain(), *this); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Extents for regions. |
| //===----------------------------------------------------------------------===// |
| |
| DefinedOrUnknownSVal |
| RegionStoreManager::getSizeInElements(ProgramStateRef state, |
| const MemRegion *R, |
| QualType EleTy) { |
| SVal Size = cast<SubRegion>(R)->getExtent(svalBuilder); |
| const llvm::APSInt *SizeInt = svalBuilder.getKnownValue(state, Size); |
| if (!SizeInt) |
| return UnknownVal(); |
| |
| CharUnits RegionSize = CharUnits::fromQuantity(SizeInt->getSExtValue()); |
| |
| if (Ctx.getAsVariableArrayType(EleTy)) { |
| // FIXME: We need to track extra state to properly record the size |
| // of VLAs. Returning UnknownVal here, however, is a stop-gap so that |
| // we don't have a divide-by-zero below. |
| return UnknownVal(); |
| } |
| |
| CharUnits EleSize = Ctx.getTypeSizeInChars(EleTy); |
| |
| // If a variable is reinterpreted as a type that doesn't fit into a larger |
| // type evenly, round it down. |
| // This is a signed value, since it's used in arithmetic with signed indices. |
| return svalBuilder.makeIntVal(RegionSize / EleSize, false); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Location and region casting. |
| //===----------------------------------------------------------------------===// |
| |
| /// ArrayToPointer - Emulates the "decay" of an array to a pointer |
| /// type. 'Array' represents the lvalue of the array being decayed |
| /// to a pointer, and the returned SVal represents the decayed |
| /// version of that lvalue (i.e., a pointer to the first element of |
| /// the array). This is called by ExprEngine when evaluating casts |
| /// from arrays to pointers. |
| SVal RegionStoreManager::ArrayToPointer(Loc Array) { |
| if (!isa<loc::MemRegionVal>(Array)) |
| return UnknownVal(); |
| |
| const MemRegion* R = cast<loc::MemRegionVal>(&Array)->getRegion(); |
| const TypedValueRegion* ArrayR = dyn_cast<TypedValueRegion>(R); |
| |
| if (!ArrayR) |
| return UnknownVal(); |
| |
| // Strip off typedefs from the ArrayRegion's ValueType. |
| QualType T = ArrayR->getValueType().getDesugaredType(Ctx); |
| const ArrayType *AT = cast<ArrayType>(T); |
| T = AT->getElementType(); |
| |
| NonLoc ZeroIdx = svalBuilder.makeZeroArrayIndex(); |
| return loc::MemRegionVal(MRMgr.getElementRegion(T, ZeroIdx, ArrayR, Ctx)); |
| } |
| |
| // This mirrors Type::getCXXRecordDeclForPointerType(), but there doesn't |
| // appear to be another need for this in the rest of the codebase. |
| static const CXXRecordDecl *GetCXXRecordDeclForReferenceType(QualType Ty) { |
| if (const ReferenceType *RT = Ty->getAs<ReferenceType>()) |
| if (const RecordType *RCT = RT->getPointeeType()->getAs<RecordType>()) |
| return dyn_cast<CXXRecordDecl>(RCT->getDecl()); |
| return 0; |
| } |
| |
| SVal RegionStoreManager::evalDerivedToBase(SVal derived, QualType baseType) { |
| const CXXRecordDecl *baseDecl; |
| |
| if (baseType->isPointerType()) |
| baseDecl = baseType->getCXXRecordDeclForPointerType(); |
| else if (baseType->isReferenceType()) |
| baseDecl = GetCXXRecordDeclForReferenceType(baseType); |
| else |
| baseDecl = baseType->getAsCXXRecordDecl(); |
| |
| assert(baseDecl && "not a CXXRecordDecl?"); |
| |
| loc::MemRegionVal *derivedRegVal = dyn_cast<loc::MemRegionVal>(&derived); |
| if (!derivedRegVal) |
| return derived; |
| |
| const MemRegion *baseReg = |
| MRMgr.getCXXBaseObjectRegion(baseDecl, derivedRegVal->getRegion()); |
| |
| return loc::MemRegionVal(baseReg); |
| } |
| |
| SVal RegionStoreManager::evalDynamicCast(SVal base, QualType derivedType, |
| bool &Failed) { |
| Failed = false; |
| |
| loc::MemRegionVal *baseRegVal = dyn_cast<loc::MemRegionVal>(&base); |
| if (!baseRegVal) |
| return UnknownVal(); |
| const MemRegion *BaseRegion = baseRegVal->stripCasts(/*StripBases=*/false); |
| |
| // Assume the derived class is a pointer or a reference to a CXX record. |
| derivedType = derivedType->getPointeeType(); |
| assert(!derivedType.isNull()); |
| const CXXRecordDecl *DerivedDecl = derivedType->getAsCXXRecordDecl(); |
| if (!DerivedDecl && !derivedType->isVoidType()) |
| return UnknownVal(); |
| |
| // Drill down the CXXBaseObject chains, which represent upcasts (casts from |
| // derived to base). |
| const MemRegion *SR = BaseRegion; |
| while (const TypedRegion *TSR = dyn_cast_or_null<TypedRegion>(SR)) { |
| QualType BaseType = TSR->getLocationType()->getPointeeType(); |
| assert(!BaseType.isNull()); |
| const CXXRecordDecl *SRDecl = BaseType->getAsCXXRecordDecl(); |
| if (!SRDecl) |
| return UnknownVal(); |
| |
| // If found the derived class, the cast succeeds. |
| if (SRDecl == DerivedDecl) |
| return loc::MemRegionVal(TSR); |
| |
| if (!derivedType->isVoidType()) { |
| // Static upcasts are marked as DerivedToBase casts by Sema, so this will |
| // only happen when multiple or virtual inheritance is involved. |
| CXXBasePaths Paths(/*FindAmbiguities=*/false, /*RecordPaths=*/true, |
| /*DetectVirtual=*/false); |
| if (SRDecl->isDerivedFrom(DerivedDecl, Paths)) { |
| SVal Result = loc::MemRegionVal(TSR); |
| const CXXBasePath &Path = *Paths.begin(); |
| for (CXXBasePath::const_iterator I = Path.begin(), E = Path.end(); |
| I != E; ++I) { |
| Result = evalDerivedToBase(Result, I->Base->getType()); |
| } |
| return Result; |
| } |
| } |
| |
| if (const CXXBaseObjectRegion *R = dyn_cast<CXXBaseObjectRegion>(TSR)) |
| // Drill down the chain to get the derived classes. |
| SR = R->getSuperRegion(); |
| else { |
| // We reached the bottom of the hierarchy. |
| |
| // If this is a cast to void*, return the region. |
| if (derivedType->isVoidType()) |
| return loc::MemRegionVal(TSR); |
| |
| // We did not find the derived class. We we must be casting the base to |
| // derived, so the cast should fail. |
| Failed = true; |
| return UnknownVal(); |
| } |
| } |
| |
| return UnknownVal(); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Loading values from regions. |
| //===----------------------------------------------------------------------===// |
| |
| Optional<SVal> RegionStoreManager::getDirectBinding(RegionBindings B, |
| const MemRegion *R) { |
| |
| if (const SVal *V = lookup(B, R, BindingKey::Direct)) |
| return *V; |
| |
| return Optional<SVal>(); |
| } |
| |
| Optional<SVal> RegionStoreManager::getDefaultBinding(RegionBindings B, |
| const MemRegion *R) { |
| if (R->isBoundable()) |
| if (const TypedValueRegion *TR = dyn_cast<TypedValueRegion>(R)) |
| if (TR->getValueType()->isUnionType()) |
| return UnknownVal(); |
| |
| if (const SVal *V = lookup(B, R, BindingKey::Default)) |
| return *V; |
| |
| return Optional<SVal>(); |
| } |
| |
| SVal RegionStoreManager::getBinding(Store store, Loc L, QualType T) { |
| assert(!isa<UnknownVal>(L) && "location unknown"); |
| assert(!isa<UndefinedVal>(L) && "location undefined"); |
| |
| // For access to concrete addresses, return UnknownVal. Checks |
| // for null dereferences (and similar errors) are done by checkers, not |
| // the Store. |
| // FIXME: We can consider lazily symbolicating such memory, but we really |
| // should defer this when we can reason easily about symbolicating arrays |
| // of bytes. |
| if (isa<loc::ConcreteInt>(L)) { |
| return UnknownVal(); |
| } |
| if (!isa<loc::MemRegionVal>(L)) { |
| return UnknownVal(); |
| } |
| |
| const MemRegion *MR = cast<loc::MemRegionVal>(L).getRegion(); |
| |
| if (isa<AllocaRegion>(MR) || |
| isa<SymbolicRegion>(MR) || |
| isa<CodeTextRegion>(MR)) { |
| if (T.isNull()) { |
| if (const TypedRegion *TR = dyn_cast<TypedRegion>(MR)) |
| T = TR->getLocationType(); |
| else { |
| const SymbolicRegion *SR = cast<SymbolicRegion>(MR); |
| T = SR->getSymbol()->getType(Ctx); |
| } |
| } |
| MR = GetElementZeroRegion(MR, T); |
| } |
| |
| // FIXME: Perhaps this method should just take a 'const MemRegion*' argument |
| // instead of 'Loc', and have the other Loc cases handled at a higher level. |
| const TypedValueRegion *R = cast<TypedValueRegion>(MR); |
| QualType RTy = R->getValueType(); |
| |
| // FIXME: We should eventually handle funny addressing. e.g.: |
| // |
| // int x = ...; |
| // int *p = &x; |
| // char *q = (char*) p; |
| // char c = *q; // returns the first byte of 'x'. |
| // |
| // Such funny addressing will occur due to layering of regions. |
| |
| if (RTy->isStructureOrClassType()) |
| return getBindingForStruct(store, R); |
| |
| // FIXME: Handle unions. |
| if (RTy->isUnionType()) |
| return UnknownVal(); |
| |
| if (RTy->isArrayType()) { |
| if (RTy->isConstantArrayType()) |
| return getBindingForArray(store, R); |
| else |
| return UnknownVal(); |
| } |
| |
| // FIXME: handle Vector types. |
| if (RTy->isVectorType()) |
| return UnknownVal(); |
| |
| if (const FieldRegion* FR = dyn_cast<FieldRegion>(R)) |
| return CastRetrievedVal(getBindingForField(store, FR), FR, T, false); |
| |
| if (const ElementRegion* ER = dyn_cast<ElementRegion>(R)) { |
| // FIXME: Here we actually perform an implicit conversion from the loaded |
| // value to the element type. Eventually we want to compose these values |
| // more intelligently. For example, an 'element' can encompass multiple |
| // bound regions (e.g., several bound bytes), or could be a subset of |
| // a larger value. |
| return CastRetrievedVal(getBindingForElement(store, ER), ER, T, false); |
| } |
| |
| if (const ObjCIvarRegion *IVR = dyn_cast<ObjCIvarRegion>(R)) { |
| // FIXME: Here we actually perform an implicit conversion from the loaded |
| // value to the ivar type. What we should model is stores to ivars |
| // that blow past the extent of the ivar. If the address of the ivar is |
| // reinterpretted, it is possible we stored a different value that could |
| // fit within the ivar. Either we need to cast these when storing them |
| // or reinterpret them lazily (as we do here). |
| return CastRetrievedVal(getBindingForObjCIvar(store, IVR), IVR, T, false); |
| } |
| |
| if (const VarRegion *VR = dyn_cast<VarRegion>(R)) { |
| // FIXME: Here we actually perform an implicit conversion from the loaded |
| // value to the variable type. What we should model is stores to variables |
| // that blow past the extent of the variable. If the address of the |
| // variable is reinterpretted, it is possible we stored a different value |
| // that could fit within the variable. Either we need to cast these when |
| // storing them or reinterpret them lazily (as we do here). |
| return CastRetrievedVal(getBindingForVar(store, VR), VR, T, false); |
| } |
| |
| RegionBindings B = GetRegionBindings(store); |
| const SVal *V = lookup(B, R, BindingKey::Direct); |
| |
| // Check if the region has a binding. |
| if (V) |
| return *V; |
| |
| // The location does not have a bound value. This means that it has |
| // the value it had upon its creation and/or entry to the analyzed |
| // function/method. These are either symbolic values or 'undefined'. |
| if (R->hasStackNonParametersStorage()) { |
| // All stack variables are considered to have undefined values |
| // upon creation. All heap allocated blocks are considered to |
| // have undefined values as well unless they are explicitly bound |
| // to specific values. |
| return UndefinedVal(); |
| } |
| |
| // All other values are symbolic. |
| return svalBuilder.getRegionValueSymbolVal(R); |
| } |
| |
| std::pair<Store, const MemRegion *> |
| RegionStoreManager::GetLazyBinding(RegionBindings B, const MemRegion *R, |
| const MemRegion *originalRegion, |
| bool includeSuffix) { |
| |
| if (originalRegion != R) { |
| if (Optional<SVal> OV = getDefaultBinding(B, R)) { |
| if (const nonloc::LazyCompoundVal *V = |
| dyn_cast<nonloc::LazyCompoundVal>(OV.getPointer())) |
| return std::make_pair(V->getStore(), V->getRegion()); |
| } |
| } |
| |
| if (const ElementRegion *ER = dyn_cast<ElementRegion>(R)) { |
| const std::pair<Store, const MemRegion *> &X = |
| GetLazyBinding(B, ER->getSuperRegion(), originalRegion); |
| |
| if (X.second) |
| return std::make_pair(X.first, |
| MRMgr.getElementRegionWithSuper(ER, X.second)); |
| } |
| else if (const FieldRegion *FR = dyn_cast<FieldRegion>(R)) { |
| const std::pair<Store, const MemRegion *> &X = |
| GetLazyBinding(B, FR->getSuperRegion(), originalRegion); |
| |
| if (X.second) { |
| if (includeSuffix) |
| return std::make_pair(X.first, |
| MRMgr.getFieldRegionWithSuper(FR, X.second)); |
| return X; |
| } |
| |
| } |
| // C++ base object region is another kind of region that we should blast |
| // through to look for lazy compound value. It is like a field region. |
| else if (const CXXBaseObjectRegion *baseReg = |
| dyn_cast<CXXBaseObjectRegion>(R)) { |
| const std::pair<Store, const MemRegion *> &X = |
| GetLazyBinding(B, baseReg->getSuperRegion(), originalRegion); |
| |
| if (X.second) { |
| if (includeSuffix) |
| return std::make_pair(X.first, |
| MRMgr.getCXXBaseObjectRegionWithSuper(baseReg, |
| X.second)); |
| return X; |
| } |
| } |
| |
| // The NULL MemRegion indicates an non-existent lazy binding. A NULL Store is |
| // possible for a valid lazy binding. |
| return std::make_pair((Store) 0, (const MemRegion *) 0); |
| } |
| |
| SVal RegionStoreManager::getBindingForElement(Store store, |
| const ElementRegion* R) { |
| // We do not currently model bindings of the CompoundLiteralregion. |
| if (isa<CompoundLiteralRegion>(R->getBaseRegion())) |
| return UnknownVal(); |
| |
| // Check if the region has a binding. |
| RegionBindings B = GetRegionBindings(store); |
| if (const Optional<SVal> &V = getDirectBinding(B, R)) |
| return *V; |
| |
| const MemRegion* superR = R->getSuperRegion(); |
| |
| // Check if the region is an element region of a string literal. |
| if (const StringRegion *StrR=dyn_cast<StringRegion>(superR)) { |
| // FIXME: Handle loads from strings where the literal is treated as |
| // an integer, e.g., *((unsigned int*)"hello") |
| QualType T = Ctx.getAsArrayType(StrR->getValueType())->getElementType(); |
| if (T != Ctx.getCanonicalType(R->getElementType())) |
| return UnknownVal(); |
| |
| const StringLiteral *Str = StrR->getStringLiteral(); |
| SVal Idx = R->getIndex(); |
| if (nonloc::ConcreteInt *CI = dyn_cast<nonloc::ConcreteInt>(&Idx)) { |
| int64_t i = CI->getValue().getSExtValue(); |
| // Abort on string underrun. This can be possible by arbitrary |
| // clients of getBindingForElement(). |
| if (i < 0) |
| return UndefinedVal(); |
| int64_t length = Str->getLength(); |
| // Technically, only i == length is guaranteed to be null. |
| // However, such overflows should be caught before reaching this point; |
| // the only time such an access would be made is if a string literal was |
| // used to initialize a larger array. |
| char c = (i >= length) ? '\0' : Str->getCodeUnit(i); |
| return svalBuilder.makeIntVal(c, T); |
| } |
| } |
| |
| // Check for loads from a code text region. For such loads, just give up. |
| if (isa<CodeTextRegion>(superR)) |
| return UnknownVal(); |
| |
| // Handle the case where we are indexing into a larger scalar object. |
| // For example, this handles: |
| // int x = ... |
| // char *y = &x; |
| // return *y; |
| // FIXME: This is a hack, and doesn't do anything really intelligent yet. |
| const RegionRawOffset &O = R->getAsArrayOffset(); |
| |
| // If we cannot reason about the offset, return an unknown value. |
| if (!O.getRegion()) |
| return UnknownVal(); |
| |
| if (const TypedValueRegion *baseR = |
| dyn_cast_or_null<TypedValueRegion>(O.getRegion())) { |
| QualType baseT = baseR->getValueType(); |
| if (baseT->isScalarType()) { |
| QualType elemT = R->getElementType(); |
| if (elemT->isScalarType()) { |
| if (Ctx.getTypeSizeInChars(baseT) >= Ctx.getTypeSizeInChars(elemT)) { |
| if (const Optional<SVal> &V = getDirectBinding(B, superR)) { |
| if (SymbolRef parentSym = V->getAsSymbol()) |
| return svalBuilder.getDerivedRegionValueSymbolVal(parentSym, R); |
| |
| if (V->isUnknownOrUndef()) |
| return *V; |
| // Other cases: give up. We are indexing into a larger object |
| // that has some value, but we don't know how to handle that yet. |
| return UnknownVal(); |
| } |
| } |
| } |
| } |
| } |
| return getBindingForFieldOrElementCommon(store, R, R->getElementType(), |
| superR); |
| } |
| |
| SVal RegionStoreManager::getBindingForField(Store store, |
| const FieldRegion* R) { |
| |
| // Check if the region has a binding. |
| RegionBindings B = GetRegionBindings(store); |
| if (const Optional<SVal> &V = getDirectBinding(B, R)) |
| return *V; |
| |
| QualType Ty = R->getValueType(); |
| return getBindingForFieldOrElementCommon(store, R, Ty, R->getSuperRegion()); |
| } |
| |
| Optional<SVal> |
| RegionStoreManager::getBindingForDerivedDefaultValue(RegionBindings B, |
| const MemRegion *superR, |
| const TypedValueRegion *R, |
| QualType Ty) { |
| |
| if (const Optional<SVal> &D = getDefaultBinding(B, superR)) { |
| const SVal &val = D.getValue(); |
| if (SymbolRef parentSym = val.getAsSymbol()) |
| return svalBuilder.getDerivedRegionValueSymbolVal(parentSym, R); |
| |
| if (val.isZeroConstant()) |
| return svalBuilder.makeZeroVal(Ty); |
| |
| if (val.isUnknownOrUndef()) |
| return val; |
| |
| // Lazy bindings are handled later. |
| if (isa<nonloc::LazyCompoundVal>(val)) |
| return Optional<SVal>(); |
| |
| llvm_unreachable("Unknown default value"); |
| } |
| |
| return Optional<SVal>(); |
| } |
| |
| SVal RegionStoreManager::getLazyBinding(const MemRegion *lazyBindingRegion, |
| Store lazyBindingStore) { |
| if (const ElementRegion *ER = dyn_cast<ElementRegion>(lazyBindingRegion)) |
| return getBindingForElement(lazyBindingStore, ER); |
| |
| return getBindingForField(lazyBindingStore, |
| cast<FieldRegion>(lazyBindingRegion)); |
| } |
| |
| SVal RegionStoreManager::getBindingForFieldOrElementCommon(Store store, |
| const TypedValueRegion *R, |
| QualType Ty, |
| const MemRegion *superR) { |
| |
| // At this point we have already checked in either getBindingForElement or |
| // getBindingForField if 'R' has a direct binding. |
| RegionBindings B = GetRegionBindings(store); |
| |
| // Lazy binding? |
| Store lazyBindingStore = NULL; |
| const MemRegion *lazyBindingRegion = NULL; |
| llvm::tie(lazyBindingStore, lazyBindingRegion) = GetLazyBinding(B, R, R, |
| true); |
| |
| if (lazyBindingRegion) |
| return getLazyBinding(lazyBindingRegion, lazyBindingStore); |
| |
| // Record whether or not we see a symbolic index. That can completely |
| // be out of scope of our lookup. |
| bool hasSymbolicIndex = false; |
| |
| while (superR) { |
| if (const Optional<SVal> &D = |
| getBindingForDerivedDefaultValue(B, superR, R, Ty)) |
| return *D; |
| |
| if (const ElementRegion *ER = dyn_cast<ElementRegion>(superR)) { |
| NonLoc index = ER->getIndex(); |
| if (!index.isConstant()) |
| hasSymbolicIndex = true; |
| } |
| |
| // If our super region is a field or element itself, walk up the region |
| // hierarchy to see if there is a default value installed in an ancestor. |
| if (const SubRegion *SR = dyn_cast<SubRegion>(superR)) { |
| superR = SR->getSuperRegion(); |
| continue; |
| } |
| break; |
| } |
| |
| if (R->hasStackNonParametersStorage()) { |
| if (isa<ElementRegion>(R)) { |
| // Currently we don't reason specially about Clang-style vectors. Check |
| // if superR is a vector and if so return Unknown. |
| if (const TypedValueRegion *typedSuperR = |
| dyn_cast<TypedValueRegion>(superR)) { |
| if (typedSuperR->getValueType()->isVectorType()) |
| return UnknownVal(); |
| } |
| } |
| |
| // FIXME: We also need to take ElementRegions with symbolic indexes into |
| // account. This case handles both directly accessing an ElementRegion |
| // with a symbolic offset, but also fields within an element with |
| // a symbolic offset. |
| if (hasSymbolicIndex) |
| return UnknownVal(); |
| |
| return UndefinedVal(); |
| } |
| |
| // All other values are symbolic. |
| return svalBuilder.getRegionValueSymbolVal(R); |
| } |
| |
| SVal RegionStoreManager::getBindingForObjCIvar(Store store, |
| const ObjCIvarRegion* R) { |
| |
| // Check if the region has a binding. |
| RegionBindings B = GetRegionBindings(store); |
| |
| if (const Optional<SVal> &V = getDirectBinding(B, R)) |
| return *V; |
| |
| const MemRegion *superR = R->getSuperRegion(); |
| |
| // Check if the super region has a default binding. |
| if (const Optional<SVal> &V = getDefaultBinding(B, superR)) { |
| if (SymbolRef parentSym = V->getAsSymbol()) |
| return svalBuilder.getDerivedRegionValueSymbolVal(parentSym, R); |
| |
| // Other cases: give up. |
| return UnknownVal(); |
| } |
| |
| return getBindingForLazySymbol(R); |
| } |
| |
| SVal RegionStoreManager::getBindingForVar(Store store, const VarRegion *R) { |
| |
| // Check if the region has a binding. |
| RegionBindings B = GetRegionBindings(store); |
| |
| if (const Optional<SVal> &V = getDirectBinding(B, R)) |
| return *V; |
| |
| // Lazily derive a value for the VarRegion. |
| const VarDecl *VD = R->getDecl(); |
| QualType T = VD->getType(); |
| const MemSpaceRegion *MS = R->getMemorySpace(); |
| |
| if (isa<UnknownSpaceRegion>(MS) || |
| isa<StackArgumentsSpaceRegion>(MS)) |
| return svalBuilder.getRegionValueSymbolVal(R); |
| |
| if (isa<GlobalsSpaceRegion>(MS)) { |
| if (isa<NonStaticGlobalSpaceRegion>(MS)) { |
| // Is 'VD' declared constant? If so, retrieve the constant value. |
| QualType CT = Ctx.getCanonicalType(T); |
| if (CT.isConstQualified()) { |
| const Expr *Init = VD->getInit(); |
| // Do the null check first, as we want to call 'IgnoreParenCasts'. |
| if (Init) |
| if (const IntegerLiteral *IL = |
| dyn_cast<IntegerLiteral>(Init->IgnoreParenCasts())) { |
| const nonloc::ConcreteInt &V = svalBuilder.makeIntVal(IL); |
| return svalBuilder.evalCast(V, Init->getType(), IL->getType()); |
| } |
| } |
| |
| if (const Optional<SVal> &V |
| = getBindingForDerivedDefaultValue(B, MS, R, CT)) |
| return V.getValue(); |
| |
| return svalBuilder.getRegionValueSymbolVal(R); |
| } |
| |
| if (T->isIntegerType()) |
| return svalBuilder.makeIntVal(0, T); |
| if (T->isPointerType()) |
| return svalBuilder.makeNull(); |
| |
| return UnknownVal(); |
| } |
| |
| return UndefinedVal(); |
| } |
| |
| SVal RegionStoreManager::getBindingForLazySymbol(const TypedValueRegion *R) { |
| // All other values are symbolic. |
| return svalBuilder.getRegionValueSymbolVal(R); |
| } |
| |
| static bool mayHaveLazyBinding(QualType Ty) { |
| return Ty->isArrayType() || Ty->isStructureOrClassType(); |
| } |
| |
| SVal RegionStoreManager::getBindingForStruct(Store store, |
| const TypedValueRegion* R) { |
| const RecordDecl *RD = R->getValueType()->castAs<RecordType>()->getDecl(); |
| if (RD->field_empty()) |
| return UnknownVal(); |
| |
| // If we already have a lazy binding, don't create a new one, |
| // unless the first field might have a lazy binding of its own. |
| // (Right now we can't tell the difference.) |
| QualType FirstFieldType = RD->field_begin()->getType(); |
| if (!mayHaveLazyBinding(FirstFieldType)) { |
| RegionBindings B = GetRegionBindings(store); |
| BindingKey K = BindingKey::Make(R, BindingKey::Default); |
| if (const nonloc::LazyCompoundVal *V = |
| dyn_cast_or_null<nonloc::LazyCompoundVal>(lookup(B, K))) { |
| return *V; |
| } |
| } |
| |
| return svalBuilder.makeLazyCompoundVal(StoreRef(store, *this), R); |
| } |
| |
| SVal RegionStoreManager::getBindingForArray(Store store, |
| const TypedValueRegion * R) { |
| const ConstantArrayType *Ty = Ctx.getAsConstantArrayType(R->getValueType()); |
| assert(Ty && "Only constant array types can have compound bindings."); |
| |
| // If we already have a lazy binding, don't create a new one, |
| // unless the first element might have a lazy binding of its own. |
| // (Right now we can't tell the difference.) |
| if (!mayHaveLazyBinding(Ty->getElementType())) { |
| RegionBindings B = GetRegionBindings(store); |
| BindingKey K = BindingKey::Make(R, BindingKey::Default); |
| if (const nonloc::LazyCompoundVal *V = |
| dyn_cast_or_null<nonloc::LazyCompoundVal>(lookup(B, K))) { |
| return *V; |
| } |
| } |
| |
| return svalBuilder.makeLazyCompoundVal(StoreRef(store, *this), R); |
| } |
| |
| bool RegionStoreManager::includedInBindings(Store store, |
| const MemRegion *region) const { |
| RegionBindings B = GetRegionBindings(store); |
| region = region->getBaseRegion(); |
| |
| // Quick path: if the base is the head of a cluster, the region is live. |
| if (B.lookup(region)) |
| return true; |
| |
| // Slow path: if the region is the VALUE of any binding, it is live. |
| for (RegionBindings::iterator RI = B.begin(), RE = B.end(); RI != RE; ++RI) { |
| const ClusterBindings &Cluster = RI.getData(); |
| for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end(); |
| CI != CE; ++CI) { |
| const SVal &D = CI.getData(); |
| if (const MemRegion *R = D.getAsRegion()) |
| if (R->getBaseRegion() == region) |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Binding values to regions. |
| //===----------------------------------------------------------------------===// |
| |
| StoreRef RegionStoreManager::killBinding(Store ST, Loc L) { |
| if (isa<loc::MemRegionVal>(L)) |
| if (const MemRegion* R = cast<loc::MemRegionVal>(L).getRegion()) |
| return StoreRef(removeBinding(GetRegionBindings(ST), |
| R).getRootWithoutRetain(), |
| *this); |
| |
| return StoreRef(ST, *this); |
| } |
| |
| StoreRef RegionStoreManager::Bind(Store store, Loc L, SVal V) { |
| if (isa<loc::ConcreteInt>(L)) |
| return StoreRef(store, *this); |
| |
| // If we get here, the location should be a region. |
| const MemRegion *R = cast<loc::MemRegionVal>(L).getRegion(); |
| |
| // Check if the region is a struct region. |
| if (const TypedValueRegion* TR = dyn_cast<TypedValueRegion>(R)) { |
| QualType Ty = TR->getValueType(); |
| if (Ty->isArrayType()) |
| return BindArray(store, TR, V); |
| if (Ty->isStructureOrClassType()) |
| return BindStruct(store, TR, V); |
| if (Ty->isVectorType()) |
| return BindVector(store, TR, V); |
| } |
| |
| if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) { |
| // Binding directly to a symbolic region should be treated as binding |
| // to element 0. |
| QualType T = SR->getSymbol()->getType(Ctx); |
| |
| // FIXME: Is this the right way to handle symbols that are references? |
| if (const PointerType *PT = T->getAs<PointerType>()) |
| T = PT->getPointeeType(); |
| else |
| T = T->getAs<ReferenceType>()->getPointeeType(); |
| |
| R = GetElementZeroRegion(SR, T); |
| } |
| |
| // Clear out bindings that may overlap with this binding. |
| |
| // Perform the binding. |
| RegionBindings B = GetRegionBindings(store); |
| B = removeSubRegionBindings(B, cast<SubRegion>(R)); |
| BindingKey Key = BindingKey::Make(R, BindingKey::Direct); |
| return StoreRef(addBinding(B, Key, V).getRootWithoutRetain(), *this); |
| } |
| |
| // FIXME: this method should be merged into Bind(). |
| StoreRef RegionStoreManager::bindCompoundLiteral(Store ST, |
| const CompoundLiteralExpr *CL, |
| const LocationContext *LC, |
| SVal V) { |
| return Bind(ST, loc::MemRegionVal(MRMgr.getCompoundLiteralRegion(CL, LC)), V); |
| } |
| |
| StoreRef RegionStoreManager::setImplicitDefaultValue(Store store, |
| const MemRegion *R, |
| QualType T) { |
| RegionBindings B = GetRegionBindings(store); |
| SVal V; |
| |
| if (Loc::isLocType(T)) |
| V = svalBuilder.makeNull(); |
| else if (T->isIntegerType()) |
| V = svalBuilder.makeZeroVal(T); |
| else if (T->isStructureOrClassType() || T->isArrayType()) { |
| // Set the default value to a zero constant when it is a structure |
| // or array. The type doesn't really matter. |
| V = svalBuilder.makeZeroVal(Ctx.IntTy); |
| } |
| else { |
| // We can't represent values of this type, but we still need to set a value |
| // to record that the region has been initialized. |
| // If this assertion ever fires, a new case should be added above -- we |
| // should know how to default-initialize any value we can symbolicate. |
| assert(!SymbolManager::canSymbolicate(T) && "This type is representable"); |
| V = UnknownVal(); |
| } |
| |
| return StoreRef(addBinding(B, R, BindingKey::Default, |
| V).getRootWithoutRetain(), *this); |
| } |
| |
| StoreRef RegionStoreManager::BindArray(Store store, const TypedValueRegion* R, |
| SVal Init) { |
| |
| const ArrayType *AT =cast<ArrayType>(Ctx.getCanonicalType(R->getValueType())); |
| QualType ElementTy = AT->getElementType(); |
| Optional<uint64_t> Size; |
| |
| if (const ConstantArrayType* CAT = dyn_cast<ConstantArrayType>(AT)) |
| Size = CAT->getSize().getZExtValue(); |
| |
| // Check if the init expr is a string literal. |
| if (loc::MemRegionVal *MRV = dyn_cast<loc::MemRegionVal>(&Init)) { |
| const StringRegion *S = cast<StringRegion>(MRV->getRegion()); |
| |
| // Treat the string as a lazy compound value. |
| nonloc::LazyCompoundVal LCV = |
| cast<nonloc::LazyCompoundVal>(svalBuilder. |
| makeLazyCompoundVal(StoreRef(store, *this), S)); |
| return BindAggregate(store, R, LCV); |
| } |
| |
| // Handle lazy compound values. |
| if (isa<nonloc::LazyCompoundVal>(Init)) |
| return BindAggregate(store, R, Init); |
| |
| // Remaining case: explicit compound values. |
| |
| if (Init.isUnknown()) |
| return setImplicitDefaultValue(store, R, ElementTy); |
| |
| nonloc::CompoundVal& CV = cast<nonloc::CompoundVal>(Init); |
| nonloc::CompoundVal::iterator VI = CV.begin(), VE = CV.end(); |
| uint64_t i = 0; |
| |
| StoreRef newStore(store, *this); |
| for (; Size.hasValue() ? i < Size.getValue() : true ; ++i, ++VI) { |
| // The init list might be shorter than the array length. |
| if (VI == VE) |
| break; |
| |
| const NonLoc &Idx = svalBuilder.makeArrayIndex(i); |
| const ElementRegion *ER = MRMgr.getElementRegion(ElementTy, Idx, R, Ctx); |
| |
| if (ElementTy->isStructureOrClassType()) |
| newStore = BindStruct(newStore.getStore(), ER, *VI); |
| else if (ElementTy->isArrayType()) |
| newStore = BindArray(newStore.getStore(), ER, *VI); |
| else |
| newStore = Bind(newStore.getStore(), svalBuilder.makeLoc(ER), *VI); |
| } |
| |
| // If the init list is shorter than the array length, set the |
| // array default value. |
| if (Size.hasValue() && i < Size.getValue()) |
| newStore = setImplicitDefaultValue(newStore.getStore(), R, ElementTy); |
| |
| return newStore; |
| } |
| |
| StoreRef RegionStoreManager::BindVector(Store store, const TypedValueRegion* R, |
| SVal V) { |
| QualType T = R->getValueType(); |
| assert(T->isVectorType()); |
| const VectorType *VT = T->getAs<VectorType>(); // Use getAs for typedefs. |
| |
| // Handle lazy compound values and symbolic values. |
| if (isa<nonloc::LazyCompoundVal>(V) || isa<nonloc::SymbolVal>(V)) |
| return BindAggregate(store, R, V); |
| |
| // We may get non-CompoundVal accidentally due to imprecise cast logic or |
| // that we are binding symbolic struct value. Kill the field values, and if |
| // the value is symbolic go and bind it as a "default" binding. |
| if (!isa<nonloc::CompoundVal>(V)) { |
| return BindAggregate(store, R, UnknownVal()); |
| } |
| |
| QualType ElemType = VT->getElementType(); |
| nonloc::CompoundVal& CV = cast<nonloc::CompoundVal>(V); |
| nonloc::CompoundVal::iterator VI = CV.begin(), VE = CV.end(); |
| unsigned index = 0, numElements = VT->getNumElements(); |
| StoreRef newStore(store, *this); |
| |
| for ( ; index != numElements ; ++index) { |
| if (VI == VE) |
| break; |
| |
| NonLoc Idx = svalBuilder.makeArrayIndex(index); |
| const ElementRegion *ER = MRMgr.getElementRegion(ElemType, Idx, R, Ctx); |
| |
| if (ElemType->isArrayType()) |
| newStore = BindArray(newStore.getStore(), ER, *VI); |
| else if (ElemType->isStructureOrClassType()) |
| newStore = BindStruct(newStore.getStore(), ER, *VI); |
| else |
| newStore = Bind(newStore.getStore(), svalBuilder.makeLoc(ER), *VI); |
| } |
| return newStore; |
| } |
| |
| StoreRef RegionStoreManager::BindStruct(Store store, const TypedValueRegion* R, |
| SVal V) { |
| |
| if (!Features.supportsFields()) |
| return StoreRef(store, *this); |
| |
| QualType T = R->getValueType(); |
| assert(T->isStructureOrClassType()); |
| |
| const RecordType* RT = T->getAs<RecordType>(); |
| RecordDecl *RD = RT->getDecl(); |
| |
| if (!RD->isCompleteDefinition()) |
| return StoreRef(store, *this); |
| |
| // Handle lazy compound values and symbolic values. |
| if (isa<nonloc::LazyCompoundVal>(V) || isa<nonloc::SymbolVal>(V)) |
| return BindAggregate(store, R, V); |
| |
| // We may get non-CompoundVal accidentally due to imprecise cast logic or |
| // that we are binding symbolic struct value. Kill the field values, and if |
| // the value is symbolic go and bind it as a "default" binding. |
| if (V.isUnknown() || !isa<nonloc::CompoundVal>(V)) |
| return BindAggregate(store, R, UnknownVal()); |
| |
| nonloc::CompoundVal& CV = cast<nonloc::CompoundVal>(V); |
| nonloc::CompoundVal::iterator VI = CV.begin(), VE = CV.end(); |
| |
| RecordDecl::field_iterator FI, FE; |
| StoreRef newStore(store, *this); |
| |
| for (FI = RD->field_begin(), FE = RD->field_end(); FI != FE; ++FI) { |
| |
| if (VI == VE) |
| break; |
| |
| // Skip any unnamed bitfields to stay in sync with the initializers. |
| if (FI->isUnnamedBitfield()) |
| continue; |
| |
| QualType FTy = FI->getType(); |
| const FieldRegion* FR = MRMgr.getFieldRegion(*FI, R); |
| |
| if (FTy->isArrayType()) |
| newStore = BindArray(newStore.getStore(), FR, *VI); |
| else if (FTy->isStructureOrClassType()) |
| newStore = BindStruct(newStore.getStore(), FR, *VI); |
| else |
| newStore = Bind(newStore.getStore(), svalBuilder.makeLoc(FR), *VI); |
| ++VI; |
| } |
| |
| // There may be fewer values in the initialize list than the fields of struct. |
| if (FI != FE) { |
| RegionBindings B = GetRegionBindings(newStore.getStore()); |
| B = addBinding(B, R, BindingKey::Default, svalBuilder.makeIntVal(0, false)); |
| newStore = StoreRef(B.getRootWithoutRetain(), *this); |
| } |
| |
| return newStore; |
| } |
| |
| StoreRef RegionStoreManager::BindAggregate(Store store, const TypedRegion *R, |
| SVal Val) { |
| // Remove the old bindings, using 'R' as the root of all regions |
| // we will invalidate. Then add the new binding. |
| RegionBindings B = GetRegionBindings(store); |
| |
| B = removeSubRegionBindings(B, R); |
| B = addBinding(B, R, BindingKey::Default, Val); |
| |
| return StoreRef(B.getRootWithoutRetain(), *this); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // "Raw" retrievals and bindings. |
| //===----------------------------------------------------------------------===// |
| |
| |
| RegionBindings RegionStoreManager::addBinding(RegionBindings B, BindingKey K, |
| SVal V) { |
| const MemRegion *Base = K.getBaseRegion(); |
| |
| const ClusterBindings *ExistingCluster = B.lookup(Base); |
| ClusterBindings Cluster = (ExistingCluster ? *ExistingCluster |
| : CBFactory.getEmptyMap()); |
| |
| ClusterBindings NewCluster = CBFactory.add(Cluster, K, V); |
| return RBFactory.add(B, Base, NewCluster); |
| } |
| |
| RegionBindings RegionStoreManager::addBinding(RegionBindings B, |
| const MemRegion *R, |
| BindingKey::Kind k, SVal V) { |
| return addBinding(B, BindingKey::Make(R, k), V); |
| } |
| |
| const SVal *RegionStoreManager::lookup(RegionBindings B, BindingKey K) { |
| const ClusterBindings *Cluster = B.lookup(K.getBaseRegion()); |
| if (!Cluster) |
| return 0; |
| |
| return Cluster->lookup(K); |
| } |
| |
| const SVal *RegionStoreManager::lookup(RegionBindings B, |
| const MemRegion *R, |
| BindingKey::Kind k) { |
| return lookup(B, BindingKey::Make(R, k)); |
| } |
| |
| RegionBindings RegionStoreManager::removeBinding(RegionBindings B, |
| BindingKey K) { |
| const MemRegion *Base = K.getBaseRegion(); |
| const ClusterBindings *Cluster = B.lookup(Base); |
| if (!Cluster) |
| return B; |
| |
| ClusterBindings NewCluster = CBFactory.remove(*Cluster, K); |
| if (NewCluster.isEmpty()) |
| return RBFactory.remove(B, Base); |
| return RBFactory.add(B, Base, NewCluster); |
| } |
| |
| RegionBindings RegionStoreManager::removeBinding(RegionBindings B, |
| const MemRegion *R, |
| BindingKey::Kind k){ |
| return removeBinding(B, BindingKey::Make(R, k)); |
| } |
| |
| RegionBindings RegionStoreManager::removeCluster(RegionBindings B, |
| const MemRegion *Base) { |
| return RBFactory.remove(B, Base); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // State pruning. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| class removeDeadBindingsWorker : |
| public ClusterAnalysis<removeDeadBindingsWorker> { |
| SmallVector<const SymbolicRegion*, 12> Postponed; |
| SymbolReaper &SymReaper; |
| const StackFrameContext *CurrentLCtx; |
| |
| public: |
| removeDeadBindingsWorker(RegionStoreManager &rm, |
| ProgramStateManager &stateMgr, |
| RegionBindings b, SymbolReaper &symReaper, |
| const StackFrameContext *LCtx) |
| : ClusterAnalysis<removeDeadBindingsWorker>(rm, stateMgr, b, |
| /* includeGlobals = */ false), |
| SymReaper(symReaper), CurrentLCtx(LCtx) {} |
| |
| // Called by ClusterAnalysis. |
| void VisitAddedToCluster(const MemRegion *baseR, const ClusterBindings &C); |
| void VisitCluster(const MemRegion *baseR, const ClusterBindings &C); |
| |
| void VisitBindingKey(BindingKey K); |
| bool UpdatePostponed(); |
| void VisitBinding(SVal V); |
| }; |
| } |
| |
| void removeDeadBindingsWorker::VisitAddedToCluster(const MemRegion *baseR, |
| const ClusterBindings &C) { |
| |
| if (const VarRegion *VR = dyn_cast<VarRegion>(baseR)) { |
| if (SymReaper.isLive(VR)) |
| AddToWorkList(baseR, &C); |
| |
| return; |
| } |
| |
| if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(baseR)) { |
| if (SymReaper.isLive(SR->getSymbol())) |
| AddToWorkList(SR, &C); |
| else |
| Postponed.push_back(SR); |
| |
| return; |
| } |
| |
| if (isa<NonStaticGlobalSpaceRegion>(baseR)) { |
| AddToWorkList(baseR, &C); |
| return; |
| } |
| |
| // CXXThisRegion in the current or parent location context is live. |
| if (const CXXThisRegion *TR = dyn_cast<CXXThisRegion>(baseR)) { |
| const StackArgumentsSpaceRegion *StackReg = |
| cast<StackArgumentsSpaceRegion>(TR->getSuperRegion()); |
| const StackFrameContext *RegCtx = StackReg->getStackFrame(); |
| if (RegCtx == CurrentLCtx || RegCtx->isParentOf(CurrentLCtx)) |
| AddToWorkList(TR, &C); |
| } |
| } |
| |
| void removeDeadBindingsWorker::VisitCluster(const MemRegion *baseR, |
| const ClusterBindings &C) { |
| for (ClusterBindings::iterator I = C.begin(), E = C.end(); I != E; ++I) { |
| VisitBindingKey(I.getKey()); |
| VisitBinding(I.getData()); |
| } |
| } |
| |
| void removeDeadBindingsWorker::VisitBinding(SVal V) { |
| // Is it a LazyCompoundVal? All referenced regions are live as well. |
| if (const nonloc::LazyCompoundVal *LCS = |
| dyn_cast<nonloc::LazyCompoundVal>(&V)) { |
| |
| const MemRegion *LazyR = LCS->getRegion(); |
| RegionBindings B = RegionStoreManager::GetRegionBindings(LCS->getStore()); |
| |
| // FIXME: This should not have to walk all bindings in the old store. |
| for (RegionBindings::iterator RI = B.begin(), RE = B.end(); RI != RE; ++RI){ |
| const ClusterBindings &Cluster = RI.getData(); |
| for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end(); |
| CI != CE; ++CI) { |
| BindingKey K = CI.getKey(); |
| if (const SubRegion *BaseR = dyn_cast<SubRegion>(K.getRegion())) { |
| if (BaseR == LazyR) |
| VisitBinding(CI.getData()); |
| else if (K.hasSymbolicOffset() && BaseR->isSubRegionOf(LazyR)) |
| VisitBinding(CI.getData()); |
| } |
| } |
| } |
| |
| return; |
| } |
| |
| // If V is a region, then add it to the worklist. |
| if (const MemRegion *R = V.getAsRegion()) { |
| AddToWorkList(R); |
| |
| // All regions captured by a block are also live. |
| if (const BlockDataRegion *BR = dyn_cast<BlockDataRegion>(R)) { |
| BlockDataRegion::referenced_vars_iterator I = BR->referenced_vars_begin(), |
| E = BR->referenced_vars_end(); |
| for ( ; I != E; ++I) |
| AddToWorkList(I.getCapturedRegion()); |
| } |
| } |
| |
| |
| // Update the set of live symbols. |
| for (SymExpr::symbol_iterator SI = V.symbol_begin(), SE = V.symbol_end(); |
| SI!=SE; ++SI) |
| SymReaper.markLive(*SI); |
| } |
| |
| void removeDeadBindingsWorker::VisitBindingKey(BindingKey K) { |
| const MemRegion *R = K.getRegion(); |
| |
| // Mark this region "live" by adding it to the worklist. This will cause |
| // use to visit all regions in the cluster (if we haven't visited them |
| // already). |
| if (AddToWorkList(R)) { |
| // Mark the symbol for any live SymbolicRegion as "live". This means we |
| // should continue to track that symbol. |
| if (const SymbolicRegion *SymR = dyn_cast<SymbolicRegion>(R)) |
| SymReaper.markLive(SymR->getSymbol()); |
| } |
| } |
| |
| bool removeDeadBindingsWorker::UpdatePostponed() { |
| // See if any postponed SymbolicRegions are actually live now, after |
| // having done a scan. |
| bool changed = false; |
| |
| for (SmallVectorImpl<const SymbolicRegion*>::iterator |
| I = Postponed.begin(), E = Postponed.end() ; I != E ; ++I) { |
| if (const SymbolicRegion *SR = cast_or_null<SymbolicRegion>(*I)) { |
| if (SymReaper.isLive(SR->getSymbol())) { |
| changed |= AddToWorkList(SR); |
| *I = NULL; |
| } |
| } |
| } |
| |
| return changed; |
| } |
| |
| StoreRef RegionStoreManager::removeDeadBindings(Store store, |
| const StackFrameContext *LCtx, |
| SymbolReaper& SymReaper) { |
| RegionBindings B = GetRegionBindings(store); |
| removeDeadBindingsWorker W(*this, StateMgr, B, SymReaper, LCtx); |
| W.GenerateClusters(); |
| |
| // Enqueue the region roots onto the worklist. |
| for (SymbolReaper::region_iterator I = SymReaper.region_begin(), |
| E = SymReaper.region_end(); I != E; ++I) { |
| W.AddToWorkList(*I); |
| } |
| |
| do W.RunWorkList(); while (W.UpdatePostponed()); |
| |
| // We have now scanned the store, marking reachable regions and symbols |
| // as live. We now remove all the regions that are dead from the store |
| // as well as update DSymbols with the set symbols that are now dead. |
| for (RegionBindings::iterator I = B.begin(), E = B.end(); I != E; ++I) { |
| const MemRegion *Base = I.getKey(); |
| |
| // If the cluster has been visited, we know the region has been marked. |
| if (W.isVisited(Base)) |
| continue; |
| |
| // Remove the dead entry. |
| B = removeCluster(B, Base); |
| |
| if (const SymbolicRegion *SymR = dyn_cast<SymbolicRegion>(Base)) |
| SymReaper.maybeDead(SymR->getSymbol()); |
| |
| // Mark all non-live symbols that this binding references as dead. |
| const ClusterBindings &Cluster = I.getData(); |
| for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end(); |
| CI != CE; ++CI) { |
| SVal X = CI.getData(); |
| SymExpr::symbol_iterator SI = X.symbol_begin(), SE = X.symbol_end(); |
| for (; SI != SE; ++SI) |
| SymReaper.maybeDead(*SI); |
| } |
| } |
| |
| return StoreRef(B.getRootWithoutRetain(), *this); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Utility methods. |
| //===----------------------------------------------------------------------===// |
| |
| void RegionStoreManager::print(Store store, raw_ostream &OS, |
| const char* nl, const char *sep) { |
| RegionBindings B = GetRegionBindings(store); |
| OS << "Store (direct and default bindings), " |
| << (void*) B.getRootWithoutRetain() |
| << " :" << nl; |
| |
| for (RegionBindings::iterator I = B.begin(), E = B.end(); I != E; ++I) { |
| const ClusterBindings &Cluster = I.getData(); |
| for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end(); |
| CI != CE; ++CI) { |
| OS << ' ' << CI.getKey() << " : " << CI.getData() << nl; |
| } |
| OS << nl; |
| } |
| } |