text: //== ProgramState.h - Path-sensitive "State" for tracking values -*- C++ -*--=//
  //
  // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
  // See https://llvm.org/LICENSE.txt for license information.
  // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  //
  //===----------------------------------------------------------------------===//
  //
  // This file defines the state of the program along the analysisa path.
  //
  //===----------------------------------------------------------------------===//
  
  #ifndef LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_PROGRAMSTATE_H
  #define LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_PROGRAMSTATE_H
  
  #include "clang/Basic/LLVM.h"
  #include "clang/StaticAnalyzer/Core/PathSensitive/ConstraintManager.h"
  #include "clang/StaticAnalyzer/Core/PathSensitive/DynamicTypeInfo.h"
  #include "clang/StaticAnalyzer/Core/PathSensitive/Environment.h"
  #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState_Fwd.h"
  #include "clang/StaticAnalyzer/Core/PathSensitive/SValBuilder.h"
  #include "clang/StaticAnalyzer/Core/PathSensitive/Store.h"
  #include "llvm/ADT/FoldingSet.h"
  #include "llvm/ADT/ImmutableMap.h"
  #include "llvm/Support/Allocator.h"
  #include <utility>
  
  namespace llvm {
  class APSInt;
  }
  
  namespace clang {
  class ASTContext;
  
  namespace ento {
  
  class AnalysisManager;
  class CallEvent;
  class CallEventManager;
  
  typedef std::unique_ptr<ConstraintManager>(*ConstraintManagerCreator)(
      ProgramStateManager &, SubEngine *);
  typedef std::unique_ptr<StoreManager>(*StoreManagerCreator)(
      ProgramStateManager &);
  
  //===----------------------------------------------------------------------===//
  // ProgramStateTrait - Traits used by the Generic Data Map of a ProgramState.
  //===----------------------------------------------------------------------===//
  
  template <typename T> struct ProgramStatePartialTrait;
  
  template <typename T> struct ProgramStateTrait {
    typedef typename T::data_type data_type;
    static inline void *MakeVoidPtr(data_type D) { return (void*) D; }
    static inline data_type MakeData(void *const* P) {
      return P ? (data_type) *P : (data_type) 0;
    }
  };
  
  /// \class ProgramState
  /// ProgramState - This class encapsulates:
  ///
  ///    1. A mapping from expressions to values (Environment)
  ///    2. A mapping from locations to values (Store)
  ///    3. Constraints on symbolic values (GenericDataMap)
  ///
  ///  Together these represent the "abstract state" of a program.
  ///
  ///  ProgramState is intended to be used as a functional object; that is,
  ///  once it is created and made "persistent" in a FoldingSet, its
  ///  values will never change.
  class ProgramState : public llvm::FoldingSetNode {
  public:
    typedef llvm::ImmutableSet<llvm::APSInt*>                IntSetTy;
    typedef llvm::ImmutableMap<void*, void*>                 GenericDataMap;
  
  private:
    void operator=(const ProgramState& R) = delete;
  
    friend class ProgramStateManager;
    friend class ExplodedGraph;
    friend class ExplodedNode;
  
    ProgramStateManager *stateMgr;
    Environment Env;           // Maps a Stmt to its current SVal.
    Store store;               // Maps a location to its current value.
    GenericDataMap   GDM;      // Custom data stored by a client of this class.
    unsigned refCount;
  
    /// makeWithStore - Return a ProgramState with the same values as the current
    ///  state with the exception of using the specified Store.
    ProgramStateRef makeWithStore(const StoreRef &store) const;
  
    void setStore(const StoreRef &storeRef);
  
  public:
    /// This ctor is used when creating the first ProgramState object.
    ProgramState(ProgramStateManager *mgr, const Environment& env,
            StoreRef st, GenericDataMap gdm);
  
    /// Copy ctor - We must explicitly define this or else the "Next" ptr
    ///  in FoldingSetNode will also get copied.
    ProgramState(const ProgramState &RHS);
  
    ~ProgramState();
  
    int64_t getID() const;
  
    /// Return the ProgramStateManager associated with this state.
    ProgramStateManager &getStateManager() const {
      return *stateMgr;
    }
  
    AnalysisManager &getAnalysisManager() const;
  
    /// Return the ConstraintManager.
    ConstraintManager &getConstraintManager() const;
  
    /// getEnvironment - Return the environment associated with this state.
    ///  The environment is the mapping from expressions to values.
    const Environment& getEnvironment() const { return Env; }
  
    /// Return the store associated with this state.  The store
    ///  is a mapping from locations to values.
    Store getStore() const { return store; }
  
  
    /// getGDM - Return the generic data map associated with this state.
    GenericDataMap getGDM() const { return GDM; }
  
    void setGDM(GenericDataMap gdm) { GDM = gdm; }
  
    /// Profile - Profile the contents of a ProgramState object for use in a
    ///  FoldingSet.  Two ProgramState objects are considered equal if they
    ///  have the same Environment, Store, and GenericDataMap.
    static void Profile(llvm::FoldingSetNodeID& ID, const ProgramState *V) {
      V->Env.Profile(ID);
      ID.AddPointer(V->store);
      V->GDM.Profile(ID);
    }
  
    /// Profile - Used to profile the contents of this object for inclusion
    ///  in a FoldingSet.
    void Profile(llvm::FoldingSetNodeID& ID) const {
      Profile(ID, this);
    }
  
    BasicValueFactory &getBasicVals() const;
    SymbolManager &getSymbolManager() const;
  
    //==---------------------------------------------------------------------==//
    // Constraints on values.
    //==---------------------------------------------------------------------==//
    //
    // Each ProgramState records constraints on symbolic values.  These constraints
    // are managed using the ConstraintManager associated with a ProgramStateManager.
    // As constraints gradually accrue on symbolic values, added constraints
    // may conflict and indicate that a state is infeasible (as no real values
    // could satisfy all the constraints).  This is the principal mechanism
    // for modeling path-sensitivity in ExprEngine/ProgramState.
    //
    // Various "assume" methods form the interface for adding constraints to
    // symbolic values.  A call to 'assume' indicates an assumption being placed
    // on one or symbolic values.  'assume' methods take the following inputs:
    //
    //  (1) A ProgramState object representing the current state.
    //
    //  (2) The assumed constraint (which is specific to a given "assume" method).
    //
    //  (3) A binary value "Assumption" that indicates whether the constraint is
    //      assumed to be true or false.
    //
    // The output of "assume*" is a new ProgramState object with the added constraints.
    // If no new state is feasible, NULL is returned.
    //
  
    /// Assumes that the value of \p cond is zero (if \p assumption is "false")
    /// or non-zero (if \p assumption is "true").
    ///
    /// This returns a new state with the added constraint on \p cond.
    /// If no new state is feasible, NULL is returned.
    LLVM_NODISCARD ProgramStateRef assume(DefinedOrUnknownSVal cond,
                                          bool assumption) const;
  
    /// Assumes both "true" and "false" for \p cond, and returns both
    /// corresponding states (respectively).
    ///
    /// This is more efficient than calling assume() twice. Note that one (but not
    /// both) of the returned states may be NULL.
    LLVM_NODISCARD std::pair<ProgramStateRef, ProgramStateRef>
    assume(DefinedOrUnknownSVal cond) const;
  
    LLVM_NODISCARD ProgramStateRef
    assumeInBound(DefinedOrUnknownSVal idx, DefinedOrUnknownSVal upperBound,
                  bool assumption, QualType IndexType = QualType()) const;
  
    /// Assumes that the value of \p Val is bounded with [\p From; \p To]
    /// (if \p assumption is "true") or it is fully out of this range
    /// (if \p assumption is "false").
    ///
    /// This returns a new state with the added constraint on \p cond.
    /// If no new state is feasible, NULL is returned.
    LLVM_NODISCARD ProgramStateRef assumeInclusiveRange(DefinedOrUnknownSVal Val,
                                                        const llvm::APSInt &From,
                                                        const llvm::APSInt &To,
                                                        bool assumption) const;
  
    /// Assumes given range both "true" and "false" for \p Val, and returns both
    /// corresponding states (respectively).
    ///
    /// This is more efficient than calling assume() twice. Note that one (but not
    /// both) of the returned states may be NULL.
    LLVM_NODISCARD std::pair<ProgramStateRef, ProgramStateRef>
    assumeInclusiveRange(DefinedOrUnknownSVal Val, const llvm::APSInt &From,
                         const llvm::APSInt &To) const;
  
    /// Check if the given SVal is not constrained to zero and is not
    ///        a zero constant.
    ConditionTruthVal isNonNull(SVal V) const;
  
    /// Check if the given SVal is constrained to zero or is a zero
    ///        constant.
    ConditionTruthVal isNull(SVal V) const;
  
    /// \return Whether values \p Lhs and \p Rhs are equal.
    ConditionTruthVal areEqual(SVal Lhs, SVal Rhs) const;
  
    /// Utility method for getting regions.
    const VarRegion* getRegion(const VarDecl *D, const LocationContext *LC) const;
  
    //==---------------------------------------------------------------------==//
    // Binding and retrieving values to/from the environment and symbolic store.
    //==---------------------------------------------------------------------==//
  
    /// Create a new state by binding the value 'V' to the statement 'S' in the
    /// state's environment.
    LLVM_NODISCARD ProgramStateRef BindExpr(const Stmt *S,
                                            const LocationContext *LCtx, SVal V,
                                            bool Invalidate = true) const;
  
    LLVM_NODISCARD ProgramStateRef bindLoc(Loc location, SVal V,
                                           const LocationContext *LCtx,
                                           bool notifyChanges = true) const;
  
    LLVM_NODISCARD ProgramStateRef bindLoc(SVal location, SVal V,
                                           const LocationContext *LCtx) const;
  
    /// Initializes the region of memory represented by \p loc with an initial
    /// value. Once initialized, all values loaded from any sub-regions of that
    /// region will be equal to \p V, unless overwritten later by the program.
    /// This method should not be used on regions that are already initialized.
    /// If you need to indicate that memory contents have suddenly become unknown
    /// within a certain region of memory, consider invalidateRegions().
    LLVM_NODISCARD ProgramStateRef
    bindDefaultInitial(SVal loc, SVal V, const LocationContext *LCtx) const;
  
    /// Performs C++ zero-initialization procedure on the region of memory
    /// represented by \p loc.
    LLVM_NODISCARD ProgramStateRef
    bindDefaultZero(SVal loc, const LocationContext *LCtx) const;
  
    LLVM_NODISCARD ProgramStateRef killBinding(Loc LV) const;
  
    /// Returns the state with bindings for the given regions
    ///  cleared from the store.
    ///
    /// Optionally invalidates global regions as well.
    ///
    /// \param Regions the set of regions to be invalidated.
    /// \param E the expression that caused the invalidation.
    /// \param BlockCount The number of times the current basic block has been
    //         visited.
    /// \param CausesPointerEscape the flag is set to true when
    ///        the invalidation entails escape of a symbol (representing a
    ///        pointer). For example, due to it being passed as an argument in a
    ///        call.
    /// \param IS the set of invalidated symbols.
    /// \param Call if non-null, the invalidated regions represent parameters to
    ///        the call and should be considered directly invalidated.
    /// \param ITraits information about special handling for a particular
    ///        region/symbol.
    LLVM_NODISCARD ProgramStateRef
    invalidateRegions(ArrayRef<const MemRegion *> Regions, const Expr *E,
                      unsigned BlockCount, const LocationContext *LCtx,
                      bool CausesPointerEscape, InvalidatedSymbols *IS = nullptr,
                      const CallEvent *Call = nullptr,
                      RegionAndSymbolInvalidationTraits *ITraits = nullptr) const;
  
    LLVM_NODISCARD ProgramStateRef
    invalidateRegions(ArrayRef<SVal> Regions, const Expr *E,
                      unsigned BlockCount, const LocationContext *LCtx,
                      bool CausesPointerEscape, InvalidatedSymbols *IS = nullptr,
                      const CallEvent *Call = nullptr,
                      RegionAndSymbolInvalidationTraits *ITraits = nullptr) const;
  
    /// enterStackFrame - Returns the state for entry to the given stack frame,
    ///  preserving the current state.
    LLVM_NODISCARD ProgramStateRef enterStackFrame(
        const CallEvent &Call, const StackFrameContext *CalleeCtx) const;
  
    /// Get the lvalue for a base class object reference.
    Loc getLValue(const CXXBaseSpecifier &BaseSpec, const SubRegion *Super) const;
  
    /// Get the lvalue for a base class object reference.
    Loc getLValue(const CXXRecordDecl *BaseClass, const SubRegion *Super,
                  bool IsVirtual) const;
  
    /// Get the lvalue for a variable reference.
    Loc getLValue(const VarDecl *D, const LocationContext *LC) const;
  
    Loc getLValue(const CompoundLiteralExpr *literal,
                  const LocationContext *LC) const;
  
    /// Get the lvalue for an ivar reference.
    SVal getLValue(const ObjCIvarDecl *decl, SVal base) const;
  
    /// Get the lvalue for a field reference.
    SVal getLValue(const FieldDecl *decl, SVal Base) const;
  
    /// Get the lvalue for an indirect field reference.
    SVal getLValue(const IndirectFieldDecl *decl, SVal Base) const;
  
    /// Get the lvalue for an array index.
    SVal getLValue(QualType ElementType, SVal Idx, SVal Base) const;
  
    /// Returns the SVal bound to the statement 'S' in the state's environment.
    SVal getSVal(const Stmt *S, const LocationContext *LCtx) const;
  
    SVal getSValAsScalarOrLoc(const Stmt *Ex, const LocationContext *LCtx) const;
  
    /// Return the value bound to the specified location.
    /// Returns UnknownVal() if none found.
    SVal getSVal(Loc LV, QualType T = QualType()) const;
  
    /// Returns the "raw" SVal bound to LV before any value simplfication.
    SVal getRawSVal(Loc LV, QualType T= QualType()) const;
  
    /// Return the value bound to the specified location.
    /// Returns UnknownVal() if none found.
    SVal getSVal(const MemRegion* R, QualType T = QualType()) const;
  
    /// Return the value bound to the specified location, assuming
    /// that the value is a scalar integer or an enumeration or a pointer.
    /// Returns UnknownVal() if none found or the region is not known to hold
    /// a value of such type.
    SVal getSValAsScalarOrLoc(const MemRegion *R) const;
  
    using region_iterator = const MemRegion **;
  
    /// Visits the symbols reachable from the given SVal using the provided
    /// SymbolVisitor.
    ///
    /// This is a convenience API. Consider using ScanReachableSymbols class
    /// directly when making multiple scans on the same state with the same
    /// visitor to avoid repeated initialization cost.
    /// \sa ScanReachableSymbols
    bool scanReachableSymbols(SVal val, SymbolVisitor& visitor) const;
  
    /// Visits the symbols reachable from the regions in the given
    /// MemRegions range using the provided SymbolVisitor.
    bool scanReachableSymbols(llvm::iterator_range<region_iterator> Reachable,
                              SymbolVisitor &visitor) const;
  
    template <typename CB> CB scanReachableSymbols(SVal val) const;
    template <typename CB> CB
    scanReachableSymbols(llvm::iterator_range<region_iterator> Reachable) const;
  
    //==---------------------------------------------------------------------==//
    // Accessing the Generic Data Map (GDM).
    //==---------------------------------------------------------------------==//
  
    void *const* FindGDM(void *K) const;
  
    template <typename T>
    LLVM_NODISCARD ProgramStateRef
    add(typename ProgramStateTrait<T>::key_type K) const;
  
    template <typename T>
    typename ProgramStateTrait<T>::data_type
    get() const {
      return ProgramStateTrait<T>::MakeData(FindGDM(ProgramStateTrait<T>::GDMIndex()));
    }
  
    template<typename T>
    typename ProgramStateTrait<T>::lookup_type
    get(typename ProgramStateTrait<T>::key_type key) const {
      void *const* d = FindGDM(ProgramStateTrait<T>::GDMIndex());
      return ProgramStateTrait<T>::Lookup(ProgramStateTrait<T>::MakeData(d), key);
    }
  
    template <typename T>
    typename ProgramStateTrait<T>::context_type get_context() const;
  
    template <typename T>
    LLVM_NODISCARD ProgramStateRef
    remove(typename ProgramStateTrait<T>::key_type K) const;
  
    template <typename T>
    LLVM_NODISCARD ProgramStateRef
    remove(typename ProgramStateTrait<T>::key_type K,
           typename ProgramStateTrait<T>::context_type C) const;
  
    template <typename T> LLVM_NODISCARD ProgramStateRef remove() const;
  
    template <typename T>
    LLVM_NODISCARD ProgramStateRef
    set(typename ProgramStateTrait<T>::data_type D) const;
  
    template <typename T>
    LLVM_NODISCARD ProgramStateRef
    set(typename ProgramStateTrait<T>::key_type K,
        typename ProgramStateTrait<T>::value_type E) const;
  
    template <typename T>
    LLVM_NODISCARD ProgramStateRef
    set(typename ProgramStateTrait<T>::key_type K,
        typename ProgramStateTrait<T>::value_type E,
        typename ProgramStateTrait<T>::context_type C) const;
  
    template<typename T>
    bool contains(typename ProgramStateTrait<T>::key_type key) const {
      void *const* d = FindGDM(ProgramStateTrait<T>::GDMIndex());
      return ProgramStateTrait<T>::Contains(ProgramStateTrait<T>::MakeData(d), key);
    }
  
    // Pretty-printing.
    void printJson(raw_ostream &Out, const LocationContext *LCtx = nullptr,
                   const char *NL = "\n", unsigned int Space = 0,
                   bool IsDot = false) const;
  
    void printDOT(raw_ostream &Out, const LocationContext *LCtx = nullptr,
                  unsigned int Space = 0) const;
  
    void dump() const;
  
  private:
    friend void ProgramStateRetain(const ProgramState *state);
    friend void ProgramStateRelease(const ProgramState *state);
  
    /// \sa invalidateValues()
    /// \sa invalidateRegions()
    ProgramStateRef
    invalidateRegionsImpl(ArrayRef<SVal> Values,
                          const Expr *E, unsigned BlockCount,
                          const LocationContext *LCtx,
                          bool ResultsInSymbolEscape,
                          InvalidatedSymbols *IS,
                          RegionAndSymbolInvalidationTraits *HTraits,
                          const CallEvent *Call) const;
  };
  
  //===----------------------------------------------------------------------===//
  // ProgramStateManager - Factory object for ProgramStates.
  //===----------------------------------------------------------------------===//
  
  class ProgramStateManager {
    friend class ProgramState;
    friend void ProgramStateRelease(const ProgramState *state);
  private:
    /// Eng - The SubEngine that owns this state manager.
    SubEngine *Eng; /* Can be null. */
  
    EnvironmentManager                   EnvMgr;
    std::unique_ptr<StoreManager>        StoreMgr;
    std::unique_ptr<ConstraintManager>   ConstraintMgr;
  
    ProgramState::GenericDataMap::Factory     GDMFactory;
  
    typedef llvm::DenseMap<void*,std::pair<void*,void (*)(void*)> > GDMContextsTy;
    GDMContextsTy GDMContexts;
  
    /// StateSet - FoldingSet containing all the states created for analyzing
    ///  a particular function.  This is used to unique states.
    llvm::FoldingSet<ProgramState> StateSet;
  
    /// Object that manages the data for all created SVals.
    std::unique_ptr<SValBuilder> svalBuilder;
  
    /// Manages memory for created CallEvents.
    std::unique_ptr<CallEventManager> CallEventMgr;
  
    /// A BumpPtrAllocator to allocate states.
    llvm::BumpPtrAllocator &Alloc;
  
    /// A vector of ProgramStates that we can reuse.
    std::vector<ProgramState *> freeStates;
  
  public:
    ProgramStateManager(ASTContext &Ctx,
                   StoreManagerCreator CreateStoreManager,
                   ConstraintManagerCreator CreateConstraintManager,
                   llvm::BumpPtrAllocator& alloc,
                   SubEngine *subeng);
  
    ~ProgramStateManager();
  
    ProgramStateRef getInitialState(const LocationContext *InitLoc);
  
    ASTContext &getContext() { return svalBuilder->getContext(); }
    const ASTContext &getContext() const { return svalBuilder->getContext(); }
  
    BasicValueFactory &getBasicVals() {
      return svalBuilder->getBasicValueFactory();
    }
  
    SValBuilder &getSValBuilder() {
      return *svalBuilder;
    }
  
    SymbolManager &getSymbolManager() {
      return svalBuilder->getSymbolManager();
    }
    const SymbolManager &getSymbolManager() const {
      return svalBuilder->getSymbolManager();
    }
  
    llvm::BumpPtrAllocator& getAllocator() { return Alloc; }
  
    MemRegionManager& getRegionManager() {
      return svalBuilder->getRegionManager();
    }
    const MemRegionManager &getRegionManager() const {
      return svalBuilder->getRegionManager();
    }
  
    CallEventManager &getCallEventManager() { return *CallEventMgr; }
  
    StoreManager &getStoreManager() { return *StoreMgr; }
    ConstraintManager &getConstraintManager() { return *ConstraintMgr; }
    SubEngine &getOwningEngine() { return *Eng; }
  
    ProgramStateRef removeDeadBindings(ProgramStateRef St,
                                      const StackFrameContext *LCtx,
                                      SymbolReaper& SymReaper);
  
  public:
  
    SVal ArrayToPointer(Loc Array, QualType ElementTy) {
      return StoreMgr->ArrayToPointer(Array, ElementTy);
    }
  
    // Methods that manipulate the GDM.
    ProgramStateRef addGDM(ProgramStateRef St, void *Key, void *Data);
    ProgramStateRef removeGDM(ProgramStateRef state, void *Key);
  
    // Methods that query & manipulate the Store.
  
    void iterBindings(ProgramStateRef state, StoreManager::BindingsHandler& F) {
      StoreMgr->iterBindings(state->getStore(), F);
    }
  
    ProgramStateRef getPersistentState(ProgramState &Impl);
    ProgramStateRef getPersistentStateWithGDM(ProgramStateRef FromState,
                                             ProgramStateRef GDMState);
  
    bool haveEqualConstraints(ProgramStateRef S1, ProgramStateRef S2) const {
      return ConstraintMgr->haveEqualConstraints(S1, S2);
    }
  
    bool haveEqualEnvironments(ProgramStateRef S1, ProgramStateRef S2) const {
      return S1->Env == S2->Env;
    }
  
    bool haveEqualStores(ProgramStateRef S1, ProgramStateRef S2) const {
      return S1->store == S2->store;
    }
  
    //==---------------------------------------------------------------------==//
    // Generic Data Map methods.
    //==---------------------------------------------------------------------==//
    //
    // ProgramStateManager and ProgramState support a "generic data map" that allows
    // different clients of ProgramState objects to embed arbitrary data within a
    // ProgramState object.  The generic data map is essentially an immutable map
    // from a "tag" (that acts as the "key" for a client) and opaque values.
    // Tags/keys and values are simply void* values.  The typical way that clients
    // generate unique tags are by taking the address of a static variable.
    // Clients are responsible for ensuring that data values referred to by a
    // the data pointer are immutable (and thus are essentially purely functional
    // data).
    //
    // The templated methods below use the ProgramStateTrait<T> class
    // to resolve keys into the GDM and to return data values to clients.
    //
  
    // Trait based GDM dispatch.
    template <typename T>
    ProgramStateRef set(ProgramStateRef st, typename ProgramStateTrait<T>::data_type D) {
      return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
                    ProgramStateTrait<T>::MakeVoidPtr(D));
    }
  
    template<typename T>
    ProgramStateRef set(ProgramStateRef st,
                       typename ProgramStateTrait<T>::key_type K,
                       typename ProgramStateTrait<T>::value_type V,
                       typename ProgramStateTrait<T>::context_type C) {
  
      return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
       ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Set(st->get<T>(), K, V, C)));
    }
  
    template <typename T>
    ProgramStateRef add(ProgramStateRef st,
                       typename ProgramStateTrait<T>::key_type K,
                       typename ProgramStateTrait<T>::context_type C) {
      return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
          ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Add(st->get<T>(), K, C)));
    }
  
    template <typename T>
    ProgramStateRef remove(ProgramStateRef st,
                          typename ProgramStateTrait<T>::key_type K,
                          typename ProgramStateTrait<T>::context_type C) {
  
      return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
       ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Remove(st->get<T>(), K, C)));
    }
  
    template <typename T>
    ProgramStateRef remove(ProgramStateRef st) {
      return removeGDM(st, ProgramStateTrait<T>::GDMIndex());
    }
  
    void *FindGDMContext(void *index,
                         void *(*CreateContext)(llvm::BumpPtrAllocator&),
                         void  (*DeleteContext)(void*));
  
    template <typename T>
    typename ProgramStateTrait<T>::context_type get_context() {
      void *p = FindGDMContext(ProgramStateTrait<T>::GDMIndex(),
                               ProgramStateTrait<T>::CreateContext,
                               ProgramStateTrait<T>::DeleteContext);
  
      return ProgramStateTrait<T>::MakeContext(p);
    }
  
    void EndPath(ProgramStateRef St) {
      ConstraintMgr->EndPath(St);
    }
  };
  
  
  //===----------------------------------------------------------------------===//
  // Out-of-line method definitions for ProgramState.
  //===----------------------------------------------------------------------===//
  
  inline ConstraintManager &ProgramState::getConstraintManager() const {
    return stateMgr->getConstraintManager();
  }
  
  inline const VarRegion* ProgramState::getRegion(const VarDecl *D,
                                                  const LocationContext *LC) const
  {
    return getStateManager().getRegionManager().getVarRegion(D, LC);
  }
  
  inline ProgramStateRef ProgramState::assume(DefinedOrUnknownSVal Cond,
                                        bool Assumption) const {
    if (Cond.isUnknown())
      return this;
  
    return getStateManager().ConstraintMgr
        ->assume(this, Cond.castAs<DefinedSVal>(), Assumption);
  }
  
  inline std::pair<ProgramStateRef , ProgramStateRef >
  ProgramState::assume(DefinedOrUnknownSVal Cond) const {
    if (Cond.isUnknown())
      return std::make_pair(this, this);
  
    return getStateManager().ConstraintMgr
        ->assumeDual(this, Cond.castAs<DefinedSVal>());
  }
  
  inline ProgramStateRef ProgramState::assumeInclusiveRange(
      DefinedOrUnknownSVal Val, const llvm::APSInt &From, const llvm::APSInt &To,
      bool Assumption) const {
    if (Val.isUnknown())
      return this;
  
    assert(Val.getAs<NonLoc>() && "Only NonLocs are supported!");
  
    return getStateManager().ConstraintMgr->assumeInclusiveRange(
        this, Val.castAs<NonLoc>(), From, To, Assumption);
  }
  
  inline std::pair<ProgramStateRef, ProgramStateRef>
  ProgramState::assumeInclusiveRange(DefinedOrUnknownSVal Val,
                                     const llvm::APSInt &From,
                                     const llvm::APSInt &To) const {
    if (Val.isUnknown())
      return std::make_pair(this, this);
  
    assert(Val.getAs<NonLoc>() && "Only NonLocs are supported!");
  
    return getStateManager().ConstraintMgr->assumeInclusiveRangeDual(
        this, Val.castAs<NonLoc>(), From, To);
  }
  
  inline ProgramStateRef ProgramState::bindLoc(SVal LV, SVal V, const LocationContext *LCtx) const {
    if (Optional<Loc> L = LV.getAs<Loc>())
      return bindLoc(*L, V, LCtx);
    return this;
  }
  
  inline Loc ProgramState::getLValue(const CXXBaseSpecifier &BaseSpec,
                                     const SubRegion *Super) const {
    const auto *Base = BaseSpec.getType()->getAsCXXRecordDecl();
    return loc::MemRegionVal(
             getStateManager().getRegionManager().getCXXBaseObjectRegion(
                                              Base, Super, BaseSpec.isVirtual()));
  }
  
  inline Loc ProgramState::getLValue(const CXXRecordDecl *BaseClass,
                                     const SubRegion *Super,
                                     bool IsVirtual) const {
    return loc::MemRegionVal(
             getStateManager().getRegionManager().getCXXBaseObjectRegion(
                                                    BaseClass, Super, IsVirtual));
  }
  
  inline Loc ProgramState::getLValue(const VarDecl *VD,
                                 const LocationContext *LC) const {
    return getStateManager().StoreMgr->getLValueVar(VD, LC);
  }
  
  inline Loc ProgramState::getLValue(const CompoundLiteralExpr *literal,
                                 const LocationContext *LC) const {
    return getStateManager().StoreMgr->getLValueCompoundLiteral(literal, LC);
  }
  
  inline SVal ProgramState::getLValue(const ObjCIvarDecl *D, SVal Base) const {
    return getStateManager().StoreMgr->getLValueIvar(D, Base);
  }
  
  inline SVal ProgramState::getLValue(const FieldDecl *D, SVal Base) const {
    return getStateManager().StoreMgr->getLValueField(D, Base);
  }
  
  inline SVal ProgramState::getLValue(const IndirectFieldDecl *D,
                                      SVal Base) const {
    StoreManager &SM = *getStateManager().StoreMgr;
    for (const auto *I : D->chain()) {
      Base = SM.getLValueField(cast<FieldDecl>(I), Base);
    }
  
    return Base;
  }
  
  inline SVal ProgramState::getLValue(QualType ElementType, SVal Idx, SVal Base) const{
    if (Optional<NonLoc> N = Idx.getAs<NonLoc>())
      return getStateManager().StoreMgr->getLValueElement(ElementType, *N, Base);
    return UnknownVal();
  }
  
  inline SVal ProgramState::getSVal(const Stmt *Ex,
                                    const LocationContext *LCtx) const{
    return Env.getSVal(EnvironmentEntry(Ex, LCtx),
                       *getStateManager().svalBuilder);
  }
  
  inline SVal
  ProgramState::getSValAsScalarOrLoc(const Stmt *S,
                                     const LocationContext *LCtx) const {
    if (const Expr *Ex = dyn_cast<Expr>(S)) {
      QualType T = Ex->getType();
      if (Ex->isGLValue() || Loc::isLocType(T) ||
          T->isIntegralOrEnumerationType())
        return getSVal(S, LCtx);
    }
  
    return UnknownVal();
  }
  
  inline SVal ProgramState::getRawSVal(Loc LV, QualType T) const {
    return getStateManager().StoreMgr->getBinding(getStore(), LV, T);
  }
  
  inline SVal ProgramState::getSVal(const MemRegion* R, QualType T) const {
    return getStateManager().StoreMgr->getBinding(getStore(),
                                                  loc::MemRegionVal(R),
                                                  T);
  }
  
  inline BasicValueFactory &ProgramState::getBasicVals() const {
    return getStateManager().getBasicVals();
  }
  
  inline SymbolManager &ProgramState::getSymbolManager() const {
    return getStateManager().getSymbolManager();
  }
  
  template<typename T>
  ProgramStateRef ProgramState::add(typename ProgramStateTrait<T>::key_type K) const {
    return getStateManager().add<T>(this, K, get_context<T>());
  }
  
  template <typename T>
  typename ProgramStateTrait<T>::context_type ProgramState::get_context() const {
    return getStateManager().get_context<T>();
  }
  
  template<typename T>
  ProgramStateRef ProgramState::remove(typename ProgramStateTrait<T>::key_type K) const {
    return getStateManager().remove<T>(this, K, get_context<T>());
  }
  
  template<typename T>
  ProgramStateRef ProgramState::remove(typename ProgramStateTrait<T>::key_type K,
                                 typename ProgramStateTrait<T>::context_type C) const {
    return getStateManager().remove<T>(this, K, C);
  }
  
  template <typename T>
  ProgramStateRef ProgramState::remove() const {
    return getStateManager().remove<T>(this);
  }
  
  template<typename T>
  ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::data_type D) const {
    return getStateManager().set<T>(this, D);
  }
  
  template<typename T>
  ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::key_type K,
                              typename ProgramStateTrait<T>::value_type E) const {
    return getStateManager().set<T>(this, K, E, get_context<T>());
  }
  
  template<typename T>
  ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::key_type K,
                              typename ProgramStateTrait<T>::value_type E,
                              typename ProgramStateTrait<T>::context_type C) const {
    return getStateManager().set<T>(this, K, E, C);
  }
  
  template <typename CB>
  CB ProgramState::scanReachableSymbols(SVal val) const {
    CB cb(this);
    scanReachableSymbols(val, cb);
    return cb;
  }
  
  template <typename CB>
  CB ProgramState::scanReachableSymbols(
      llvm::iterator_range<region_iterator> Reachable) const {
    CB cb(this);
    scanReachableSymbols(Reachable, cb);
    return cb;
  }
  
  /// \class ScanReachableSymbols
  /// A utility class that visits the reachable symbols using a custom
  /// SymbolVisitor. Terminates recursive traversal when the visitor function
  /// returns false.
  class ScanReachableSymbols {
    typedef llvm::DenseSet<const void*> VisitedItems;
  
    VisitedItems visited;
    ProgramStateRef state;
    SymbolVisitor &visitor;
  public:
    ScanReachableSymbols(ProgramStateRef st, SymbolVisitor &v)
        : state(std::move(st)), visitor(v) {}
  
    bool scan(nonloc::LazyCompoundVal val);
    bool scan(nonloc::CompoundVal val);
    bool scan(SVal val);
    bool scan(const MemRegion *R);
    bool scan(const SymExpr *sym);
  };
  
  } // end ento namespace
  
  } // end clang namespace
  
  #endif
  