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//== Store.h - Interface for maps from Locations to Values ------*- C++ -*--==//
// The LLVM Compiler Infrastructure
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
// This file defined the types Store and StoreManager.
#include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/SValBuilder.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/StoreRef.h"
#include "llvm/ADT/DenseSet.h"
namespace clang {
class Stmt;
class Expr;
class ObjCIvarDecl;
class CXXBasePath;
class StackFrameContext;
namespace ento {
class CallEvent;
class ProgramState;
class ProgramStateManager;
class ScanReachableSymbols;
typedef llvm::DenseSet<SymbolRef> InvalidatedSymbols;
class StoreManager {
SValBuilder &svalBuilder;
ProgramStateManager &StateMgr;
/// MRMgr - Manages region objects associated with this StoreManager.
MemRegionManager &MRMgr;
ASTContext &Ctx;
StoreManager(ProgramStateManager &stateMgr);
virtual ~StoreManager() {}
/// Return the value bound to specified location in a given state.
/// \param[in] store The analysis state.
/// \param[in] loc The symbolic memory location.
/// \param[in] T An optional type that provides a hint indicating the
/// expected type of the returned value. This is used if the value is
/// lazily computed.
/// \return The value bound to the location \c loc.
virtual SVal getBinding(Store store, Loc loc, QualType T = QualType()) = 0;
/// Return the default value bound to a region in a given store. The default
/// binding is the value of sub-regions that were not initialized separately
/// from their base region. For example, if the structure is zero-initialized
/// upon construction, this method retrieves the concrete zero value, even if
/// some or all fields were later overwritten manually. Default binding may be
/// an unknown, undefined, concrete, or symbolic value.
/// \param[in] store The store in which to make the lookup.
/// \param[in] R The region to find the default binding for.
/// \return The default value bound to the region in the store, if a default
/// binding exists.
virtual Optional<SVal> getDefaultBinding(Store store, const MemRegion *R) = 0;
/// Return the default value bound to a LazyCompoundVal. The default binding
/// is used to represent the value of any fields or elements within the
/// structure represented by the LazyCompoundVal which were not initialized
/// explicitly separately from the whole structure. Default binding may be an
/// unknown, undefined, concrete, or symbolic value.
/// \param[in] lcv The lazy compound value.
/// \return The default value bound to the LazyCompoundVal \c lcv, if a
/// default binding exists.
Optional<SVal> getDefaultBinding(nonloc::LazyCompoundVal lcv) {
return getDefaultBinding(lcv.getStore(), lcv.getRegion());
/// Return a state with the specified value bound to the given location.
/// \param[in] store The analysis state.
/// \param[in] loc The symbolic memory location.
/// \param[in] val The value to bind to location \c loc.
/// \return A pointer to a ProgramState object that contains the same
/// bindings as \c state with the addition of having the value specified
/// by \c val bound to the location given for \c loc.
virtual StoreRef Bind(Store store, Loc loc, SVal val) = 0;
virtual StoreRef BindDefault(Store store, const MemRegion *R, SVal V);
/// \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.
virtual StoreRef killBinding(Store ST, Loc L) = 0;
/// getInitialStore - Returns the initial "empty" store representing the
/// value bindings upon entry to an analyzed function.
virtual StoreRef getInitialStore(const LocationContext *InitLoc) = 0;
/// getRegionManager - Returns the internal RegionManager object that is
/// used to query and manipulate MemRegion objects.
MemRegionManager& getRegionManager() { return MRMgr; }
virtual Loc getLValueVar(const VarDecl *VD, const LocationContext *LC) {
return svalBuilder.makeLoc(MRMgr.getVarRegion(VD, LC));
Loc getLValueCompoundLiteral(const CompoundLiteralExpr *CL,
const LocationContext *LC) {
return loc::MemRegionVal(MRMgr.getCompoundLiteralRegion(CL, LC));
virtual SVal getLValueIvar(const ObjCIvarDecl *decl, SVal base);
virtual SVal getLValueField(const FieldDecl *D, SVal Base) {
return getLValueFieldOrIvar(D, Base);
virtual SVal getLValueElement(QualType elementType, NonLoc offset, SVal Base);
// FIXME: This should soon be eliminated altogether; clients should deal with
// region extents directly.
virtual DefinedOrUnknownSVal getSizeInElements(ProgramStateRef state,
const MemRegion *region,
QualType EleTy) {
return UnknownVal();
/// ArrayToPointer - Used by ExprEngine::VistCast to handle implicit
/// conversions between arrays and pointers.
virtual SVal ArrayToPointer(Loc Array, QualType ElementTy) = 0;
/// Evaluates a chain of derived-to-base casts through the path specified in
/// \p Cast.
SVal evalDerivedToBase(SVal Derived, const CastExpr *Cast);
/// Evaluates a chain of derived-to-base casts through the specified path.
SVal evalDerivedToBase(SVal Derived, const CXXBasePath &CastPath);
/// Evaluates a derived-to-base cast through a single level of derivation.
SVal evalDerivedToBase(SVal Derived, QualType DerivedPtrType,
bool IsVirtual);
/// \brief Attempts to do a down cast. Used to model BaseToDerived and C++
/// dynamic_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).
/// The distinction of this case from the next one is necessary to model
/// dynamic_cast.
/// - 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.
SVal attemptDownCast(SVal Base, QualType DerivedPtrType, bool &Failed);
const ElementRegion *GetElementZeroRegion(const SubRegion *R, QualType T);
/// castRegion - Used by ExprEngine::VisitCast to handle casts from
/// a MemRegion* to a specific location type. 'R' is the region being
/// casted and 'CastToTy' the result type of the cast.
const MemRegion *castRegion(const MemRegion *region, QualType CastToTy);
virtual StoreRef removeDeadBindings(Store store, const StackFrameContext *LCtx,
SymbolReaper& SymReaper) = 0;
virtual bool includedInBindings(Store store,
const MemRegion *region) const = 0;
/// If the StoreManager supports it, increment the reference count of
/// the specified Store object.
virtual void incrementReferenceCount(Store store) {}
/// 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.
virtual void decrementReferenceCount(Store store) {}
typedef SmallVector<const MemRegion *, 8> InvalidatedRegions;
/// invalidateRegions - Clears out the specified regions from the store,
/// marking their values as unknown. Depending on the store, this may also
/// invalidate additional regions that may have changed based on accessing
/// the given regions. Optionally, invalidates non-static globals as well.
/// \param[in] store The initial store
/// \param[in] Values The values to invalidate.
/// \param[in] E The current statement being evaluated. Used to conjure
/// symbols to mark the values of invalidated regions.
/// \param[in] Count The current block count. Used to conjure
/// symbols to mark the values of invalidated regions.
/// \param[in] Call The call expression which will be used to determine which
/// globals should get invalidated.
/// \param[in,out] IS A set to fill with any symbols that are no longer
/// accessible. Pass \c NULL if this information will not be used.
/// \param[in] ITraits Information about invalidation for a particular
/// region/symbol.
/// \param[in,out] InvalidatedTopLevel A vector to fill with regions
//// explicitly being invalidated. Pass \c NULL if this
/// information will not be used.
/// \param[in,out] Invalidated A vector to fill with any regions being
/// invalidated. This should include any regions explicitly invalidated
/// even if they do not currently have bindings. Pass \c NULL if this
/// information will not be used.
virtual StoreRef invalidateRegions(Store store,
ArrayRef<SVal> Values,
const Expr *E, unsigned Count,
const LocationContext *LCtx,
const CallEvent *Call,
InvalidatedSymbols &IS,
RegionAndSymbolInvalidationTraits &ITraits,
InvalidatedRegions *InvalidatedTopLevel,
InvalidatedRegions *Invalidated) = 0;
/// enterStackFrame - Let the StoreManager to do something when execution
/// engine is about to execute into a callee.
StoreRef enterStackFrame(Store store,
const CallEvent &Call,
const StackFrameContext *CalleeCtx);
/// Finds the transitive closure of symbols within the given region.
/// Returns false if the visitor aborted the scan.
virtual bool scanReachableSymbols(Store S, const MemRegion *R,
ScanReachableSymbols &Visitor) = 0;
virtual void print(Store store, raw_ostream &Out,
const char* nl, const char *sep) = 0;
class BindingsHandler {
virtual ~BindingsHandler();
virtual bool HandleBinding(StoreManager& SMgr, Store store,
const MemRegion *region, SVal val) = 0;
class FindUniqueBinding :
public BindingsHandler {
SymbolRef Sym;
const MemRegion* Binding;
bool First;
FindUniqueBinding(SymbolRef sym)
: Sym(sym), Binding(nullptr), First(true) {}
bool HandleBinding(StoreManager& SMgr, Store store, const MemRegion* R,
SVal val) override;
explicit operator bool() { return First && Binding; }
const MemRegion *getRegion() { return Binding; }
/// iterBindings - Iterate over the bindings in the Store.
virtual void iterBindings(Store store, BindingsHandler& f) = 0;
const ElementRegion *MakeElementRegion(const SubRegion *baseRegion,
QualType pointeeTy,
uint64_t index = 0);
/// CastRetrievedVal - Used by subclasses of StoreManager to implement
/// implicit casts that arise from loads from regions that are reinterpreted
/// as another region.
SVal CastRetrievedVal(SVal val, const TypedValueRegion *region,
QualType castTy, bool performTestOnly = true);
SVal getLValueFieldOrIvar(const Decl *decl, SVal base);
inline StoreRef::StoreRef(Store store, StoreManager & smgr)
: store(store), mgr(smgr) {
if (store)
inline StoreRef::StoreRef(const StoreRef &sr)
: store(, mgr(sr.mgr)
if (store)
inline StoreRef::~StoreRef() {
if (store)
inline StoreRef &StoreRef::operator=(StoreRef const &newStore) {
assert(&newStore.mgr == &mgr);
if (store != {
store = newStore.getStore();
return *this;
// FIXME: Do we need to pass ProgramStateManager anymore?
CreateRegionStoreManager(ProgramStateManager &StMgr);
CreateFieldsOnlyRegionStoreManager(ProgramStateManager &StMgr);
} // end GR namespace
} // end clang namespace