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      1 //== ProgramState.h - Path-sensitive "State" for tracking values -*- C++ -*--=//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is distributed under the University of Illinois Open Source
      6 // License. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 //
     10 // This file defines the state of the program along the analysisa path.
     11 //
     12 //===----------------------------------------------------------------------===//
     13 
     14 #ifndef LLVM_CLANG_GR_VALUESTATE_H
     15 #define LLVM_CLANG_GR_VALUESTATE_H
     16 
     17 #include "clang/Basic/LLVM.h"
     18 #include "clang/StaticAnalyzer/Core/PathSensitive/ConstraintManager.h"
     19 #include "clang/StaticAnalyzer/Core/PathSensitive/DynamicTypeInfo.h"
     20 #include "clang/StaticAnalyzer/Core/PathSensitive/Environment.h"
     21 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState_Fwd.h"
     22 #include "clang/StaticAnalyzer/Core/PathSensitive/SValBuilder.h"
     23 #include "clang/StaticAnalyzer/Core/PathSensitive/Store.h"
     24 #include "clang/StaticAnalyzer/Core/PathSensitive/TaintTag.h"
     25 #include "llvm/ADT/FoldingSet.h"
     26 #include "llvm/ADT/ImmutableMap.h"
     27 #include "llvm/ADT/PointerIntPair.h"
     28 
     29 namespace llvm {
     30 class APSInt;
     31 class BumpPtrAllocator;
     32 }
     33 
     34 namespace clang {
     35 class ASTContext;
     36 
     37 namespace ento {
     38 
     39 class CallEvent;
     40 class CallEventManager;
     41 
     42 typedef ConstraintManager* (*ConstraintManagerCreator)(ProgramStateManager&,
     43                                                        SubEngine*);
     44 typedef StoreManager* (*StoreManagerCreator)(ProgramStateManager&);
     45 
     46 //===----------------------------------------------------------------------===//
     47 // ProgramStateTrait - Traits used by the Generic Data Map of a ProgramState.
     48 //===----------------------------------------------------------------------===//
     49 
     50 template <typename T> struct ProgramStatePartialTrait;
     51 
     52 template <typename T> struct ProgramStateTrait {
     53   typedef typename T::data_type data_type;
     54   static inline void *MakeVoidPtr(data_type D) { return (void*) D; }
     55   static inline data_type MakeData(void *const* P) {
     56     return P ? (data_type) *P : (data_type) 0;
     57   }
     58 };
     59 
     60 /// \class ProgramState
     61 /// ProgramState - This class encapsulates:
     62 ///
     63 ///    1. A mapping from expressions to values (Environment)
     64 ///    2. A mapping from locations to values (Store)
     65 ///    3. Constraints on symbolic values (GenericDataMap)
     66 ///
     67 ///  Together these represent the "abstract state" of a program.
     68 ///
     69 ///  ProgramState is intended to be used as a functional object; that is,
     70 ///  once it is created and made "persistent" in a FoldingSet, its
     71 ///  values will never change.
     72 class ProgramState : public llvm::FoldingSetNode {
     73 public:
     74   typedef llvm::ImmutableSet<llvm::APSInt*>                IntSetTy;
     75   typedef llvm::ImmutableMap<void*, void*>                 GenericDataMap;
     76 
     77 private:
     78   void operator=(const ProgramState& R) LLVM_DELETED_FUNCTION;
     79 
     80   friend class ProgramStateManager;
     81   friend class ExplodedGraph;
     82   friend class ExplodedNode;
     83 
     84   ProgramStateManager *stateMgr;
     85   Environment Env;           // Maps a Stmt to its current SVal.
     86   Store store;               // Maps a location to its current value.
     87   GenericDataMap   GDM;      // Custom data stored by a client of this class.
     88   unsigned refCount;
     89 
     90   /// makeWithStore - Return a ProgramState with the same values as the current
     91   ///  state with the exception of using the specified Store.
     92   ProgramStateRef makeWithStore(const StoreRef &store) const;
     93 
     94   void setStore(const StoreRef &storeRef);
     95 
     96 public:
     97   /// This ctor is used when creating the first ProgramState object.
     98   ProgramState(ProgramStateManager *mgr, const Environment& env,
     99           StoreRef st, GenericDataMap gdm);
    100 
    101   /// Copy ctor - We must explicitly define this or else the "Next" ptr
    102   ///  in FoldingSetNode will also get copied.
    103   ProgramState(const ProgramState &RHS);
    104 
    105   ~ProgramState();
    106 
    107   /// Return the ProgramStateManager associated with this state.
    108   ProgramStateManager &getStateManager() const {
    109     return *stateMgr;
    110   }
    111 
    112   /// Return the ConstraintManager.
    113   ConstraintManager &getConstraintManager() const;
    114 
    115   /// getEnvironment - Return the environment associated with this state.
    116   ///  The environment is the mapping from expressions to values.
    117   const Environment& getEnvironment() const { return Env; }
    118 
    119   /// Return the store associated with this state.  The store
    120   ///  is a mapping from locations to values.
    121   Store getStore() const { return store; }
    122 
    123 
    124   /// getGDM - Return the generic data map associated with this state.
    125   GenericDataMap getGDM() const { return GDM; }
    126 
    127   void setGDM(GenericDataMap gdm) { GDM = gdm; }
    128 
    129   /// Profile - Profile the contents of a ProgramState object for use in a
    130   ///  FoldingSet.  Two ProgramState objects are considered equal if they
    131   ///  have the same Environment, Store, and GenericDataMap.
    132   static void Profile(llvm::FoldingSetNodeID& ID, const ProgramState *V) {
    133     V->Env.Profile(ID);
    134     ID.AddPointer(V->store);
    135     V->GDM.Profile(ID);
    136   }
    137 
    138   /// Profile - Used to profile the contents of this object for inclusion
    139   ///  in a FoldingSet.
    140   void Profile(llvm::FoldingSetNodeID& ID) const {
    141     Profile(ID, this);
    142   }
    143 
    144   BasicValueFactory &getBasicVals() const;
    145   SymbolManager &getSymbolManager() const;
    146 
    147   //==---------------------------------------------------------------------==//
    148   // Constraints on values.
    149   //==---------------------------------------------------------------------==//
    150   //
    151   // Each ProgramState records constraints on symbolic values.  These constraints
    152   // are managed using the ConstraintManager associated with a ProgramStateManager.
    153   // As constraints gradually accrue on symbolic values, added constraints
    154   // may conflict and indicate that a state is infeasible (as no real values
    155   // could satisfy all the constraints).  This is the principal mechanism
    156   // for modeling path-sensitivity in ExprEngine/ProgramState.
    157   //
    158   // Various "assume" methods form the interface for adding constraints to
    159   // symbolic values.  A call to 'assume' indicates an assumption being placed
    160   // on one or symbolic values.  'assume' methods take the following inputs:
    161   //
    162   //  (1) A ProgramState object representing the current state.
    163   //
    164   //  (2) The assumed constraint (which is specific to a given "assume" method).
    165   //
    166   //  (3) A binary value "Assumption" that indicates whether the constraint is
    167   //      assumed to be true or false.
    168   //
    169   // The output of "assume*" is a new ProgramState object with the added constraints.
    170   // If no new state is feasible, NULL is returned.
    171   //
    172 
    173   /// Assumes that the value of \p cond is zero (if \p assumption is "false")
    174   /// or non-zero (if \p assumption is "true").
    175   ///
    176   /// This returns a new state with the added constraint on \p cond.
    177   /// If no new state is feasible, NULL is returned.
    178   ProgramStateRef assume(DefinedOrUnknownSVal cond, bool assumption) const;
    179 
    180   /// Assumes both "true" and "false" for \p cond, and returns both
    181   /// corresponding states (respectively).
    182   ///
    183   /// This is more efficient than calling assume() twice. Note that one (but not
    184   /// both) of the returned states may be NULL.
    185   std::pair<ProgramStateRef, ProgramStateRef>
    186   assume(DefinedOrUnknownSVal cond) const;
    187 
    188   ProgramStateRef assumeInBound(DefinedOrUnknownSVal idx,
    189                                DefinedOrUnknownSVal upperBound,
    190                                bool assumption,
    191                                QualType IndexType = QualType()) const;
    192 
    193   /// \brief Check if the given SVal is constrained to zero or is a zero
    194   ///        constant.
    195   ConditionTruthVal isNull(SVal V) const;
    196 
    197   /// Utility method for getting regions.
    198   const VarRegion* getRegion(const VarDecl *D, const LocationContext *LC) const;
    199 
    200   //==---------------------------------------------------------------------==//
    201   // Binding and retrieving values to/from the environment and symbolic store.
    202   //==---------------------------------------------------------------------==//
    203 
    204   /// \brief Create a new state with the specified CompoundLiteral binding.
    205   /// \param CL the compound literal expression (the binding key)
    206   /// \param LC the LocationContext of the binding
    207   /// \param V the value to bind.
    208   ProgramStateRef bindCompoundLiteral(const CompoundLiteralExpr *CL,
    209                                       const LocationContext *LC,
    210                                       SVal V) const;
    211 
    212   /// Create a new state by binding the value 'V' to the statement 'S' in the
    213   /// state's environment.
    214   ProgramStateRef BindExpr(const Stmt *S, const LocationContext *LCtx,
    215                                SVal V, bool Invalidate = true) const;
    216 
    217   ProgramStateRef bindLoc(Loc location,
    218                           SVal V,
    219                           bool notifyChanges = true) const;
    220 
    221   ProgramStateRef bindLoc(SVal location, SVal V) const;
    222 
    223   ProgramStateRef bindDefault(SVal loc, SVal V) const;
    224 
    225   ProgramStateRef killBinding(Loc LV) const;
    226 
    227   /// \brief Returns the state with bindings for the given regions
    228   ///  cleared from the store.
    229   ///
    230   /// Optionally invalidates global regions as well.
    231   ///
    232   /// \param Regions the set of regions to be invalidated.
    233   /// \param E the expression that caused the invalidation.
    234   /// \param BlockCount The number of times the current basic block has been
    235   //         visited.
    236   /// \param CausesPointerEscape the flag is set to true when
    237   ///        the invalidation entails escape of a symbol (representing a
    238   ///        pointer). For example, due to it being passed as an argument in a
    239   ///        call.
    240   /// \param IS the set of invalidated symbols.
    241   /// \param Call if non-null, the invalidated regions represent parameters to
    242   ///        the call and should be considered directly invalidated.
    243   ProgramStateRef invalidateRegions(ArrayRef<const MemRegion *> Regions,
    244                                     const Expr *E, unsigned BlockCount,
    245                                     const LocationContext *LCtx,
    246                                     bool CausesPointerEscape,
    247                                     InvalidatedSymbols *IS = 0,
    248                                     const CallEvent *Call = 0) const;
    249 
    250   /// enterStackFrame - Returns the state for entry to the given stack frame,
    251   ///  preserving the current state.
    252   ProgramStateRef enterStackFrame(const CallEvent &Call,
    253                                   const StackFrameContext *CalleeCtx) const;
    254 
    255   /// Get the lvalue for a variable reference.
    256   Loc getLValue(const VarDecl *D, const LocationContext *LC) const;
    257 
    258   Loc getLValue(const CompoundLiteralExpr *literal,
    259                 const LocationContext *LC) const;
    260 
    261   /// Get the lvalue for an ivar reference.
    262   SVal getLValue(const ObjCIvarDecl *decl, SVal base) const;
    263 
    264   /// Get the lvalue for a field reference.
    265   SVal getLValue(const FieldDecl *decl, SVal Base) const;
    266 
    267   /// Get the lvalue for an indirect field reference.
    268   SVal getLValue(const IndirectFieldDecl *decl, SVal Base) const;
    269 
    270   /// Get the lvalue for an array index.
    271   SVal getLValue(QualType ElementType, SVal Idx, SVal Base) const;
    272 
    273   /// Returns the SVal bound to the statement 'S' in the state's environment.
    274   SVal getSVal(const Stmt *S, const LocationContext *LCtx) const;
    275 
    276   SVal getSValAsScalarOrLoc(const Stmt *Ex, const LocationContext *LCtx) const;
    277 
    278   /// \brief Return the value bound to the specified location.
    279   /// Returns UnknownVal() if none found.
    280   SVal getSVal(Loc LV, QualType T = QualType()) const;
    281 
    282   /// Returns the "raw" SVal bound to LV before any value simplfication.
    283   SVal getRawSVal(Loc LV, QualType T= QualType()) const;
    284 
    285   /// \brief Return the value bound to the specified location.
    286   /// Returns UnknownVal() if none found.
    287   SVal getSVal(const MemRegion* R) const;
    288 
    289   SVal getSValAsScalarOrLoc(const MemRegion *R) const;
    290 
    291   /// \brief Visits the symbols reachable from the given SVal using the provided
    292   /// SymbolVisitor.
    293   ///
    294   /// This is a convenience API. Consider using ScanReachableSymbols class
    295   /// directly when making multiple scans on the same state with the same
    296   /// visitor to avoid repeated initialization cost.
    297   /// \sa ScanReachableSymbols
    298   bool scanReachableSymbols(SVal val, SymbolVisitor& visitor) const;
    299 
    300   /// \brief Visits the symbols reachable from the SVals in the given range
    301   /// using the provided SymbolVisitor.
    302   bool scanReachableSymbols(const SVal *I, const SVal *E,
    303                             SymbolVisitor &visitor) const;
    304 
    305   /// \brief Visits the symbols reachable from the regions in the given
    306   /// MemRegions range using the provided SymbolVisitor.
    307   bool scanReachableSymbols(const MemRegion * const *I,
    308                             const MemRegion * const *E,
    309                             SymbolVisitor &visitor) const;
    310 
    311   template <typename CB> CB scanReachableSymbols(SVal val) const;
    312   template <typename CB> CB scanReachableSymbols(const SVal *beg,
    313                                                  const SVal *end) const;
    314 
    315   template <typename CB> CB
    316   scanReachableSymbols(const MemRegion * const *beg,
    317                        const MemRegion * const *end) const;
    318 
    319   /// Create a new state in which the statement is marked as tainted.
    320   ProgramStateRef addTaint(const Stmt *S, const LocationContext *LCtx,
    321                                TaintTagType Kind = TaintTagGeneric) const;
    322 
    323   /// Create a new state in which the symbol is marked as tainted.
    324   ProgramStateRef addTaint(SymbolRef S,
    325                                TaintTagType Kind = TaintTagGeneric) const;
    326 
    327   /// Create a new state in which the region symbol is marked as tainted.
    328   ProgramStateRef addTaint(const MemRegion *R,
    329                                TaintTagType Kind = TaintTagGeneric) const;
    330 
    331   /// Check if the statement is tainted in the current state.
    332   bool isTainted(const Stmt *S, const LocationContext *LCtx,
    333                  TaintTagType Kind = TaintTagGeneric) const;
    334   bool isTainted(SVal V, TaintTagType Kind = TaintTagGeneric) const;
    335   bool isTainted(SymbolRef Sym, TaintTagType Kind = TaintTagGeneric) const;
    336   bool isTainted(const MemRegion *Reg, TaintTagType Kind=TaintTagGeneric) const;
    337 
    338   /// \brief Get dynamic type information for a region.
    339   DynamicTypeInfo getDynamicTypeInfo(const MemRegion *Reg) const;
    340 
    341   /// \brief Set dynamic type information of the region; return the new state.
    342   ProgramStateRef setDynamicTypeInfo(const MemRegion *Reg,
    343                                      DynamicTypeInfo NewTy) const;
    344 
    345   /// \brief Set dynamic type information of the region; return the new state.
    346   ProgramStateRef setDynamicTypeInfo(const MemRegion *Reg,
    347                                      QualType NewTy,
    348                                      bool CanBeSubClassed = true) const {
    349     return setDynamicTypeInfo(Reg, DynamicTypeInfo(NewTy, CanBeSubClassed));
    350   }
    351 
    352   //==---------------------------------------------------------------------==//
    353   // Accessing the Generic Data Map (GDM).
    354   //==---------------------------------------------------------------------==//
    355 
    356   void *const* FindGDM(void *K) const;
    357 
    358   template<typename T>
    359   ProgramStateRef add(typename ProgramStateTrait<T>::key_type K) const;
    360 
    361   template <typename T>
    362   typename ProgramStateTrait<T>::data_type
    363   get() const {
    364     return ProgramStateTrait<T>::MakeData(FindGDM(ProgramStateTrait<T>::GDMIndex()));
    365   }
    366 
    367   template<typename T>
    368   typename ProgramStateTrait<T>::lookup_type
    369   get(typename ProgramStateTrait<T>::key_type key) const {
    370     void *const* d = FindGDM(ProgramStateTrait<T>::GDMIndex());
    371     return ProgramStateTrait<T>::Lookup(ProgramStateTrait<T>::MakeData(d), key);
    372   }
    373 
    374   template <typename T>
    375   typename ProgramStateTrait<T>::context_type get_context() const;
    376 
    377 
    378   template<typename T>
    379   ProgramStateRef remove(typename ProgramStateTrait<T>::key_type K) const;
    380 
    381   template<typename T>
    382   ProgramStateRef remove(typename ProgramStateTrait<T>::key_type K,
    383                         typename ProgramStateTrait<T>::context_type C) const;
    384   template <typename T>
    385   ProgramStateRef remove() const;
    386 
    387   template<typename T>
    388   ProgramStateRef set(typename ProgramStateTrait<T>::data_type D) const;
    389 
    390   template<typename T>
    391   ProgramStateRef set(typename ProgramStateTrait<T>::key_type K,
    392                      typename ProgramStateTrait<T>::value_type E) const;
    393 
    394   template<typename T>
    395   ProgramStateRef set(typename ProgramStateTrait<T>::key_type K,
    396                      typename ProgramStateTrait<T>::value_type E,
    397                      typename ProgramStateTrait<T>::context_type C) const;
    398 
    399   template<typename T>
    400   bool contains(typename ProgramStateTrait<T>::key_type key) const {
    401     void *const* d = FindGDM(ProgramStateTrait<T>::GDMIndex());
    402     return ProgramStateTrait<T>::Contains(ProgramStateTrait<T>::MakeData(d), key);
    403   }
    404 
    405   // Pretty-printing.
    406   void print(raw_ostream &Out, const char *nl = "\n",
    407              const char *sep = "") const;
    408   void printDOT(raw_ostream &Out) const;
    409   void printTaint(raw_ostream &Out, const char *nl = "\n",
    410                   const char *sep = "") const;
    411 
    412   void dump() const;
    413   void dumpTaint() const;
    414 
    415 private:
    416   friend void ProgramStateRetain(const ProgramState *state);
    417   friend void ProgramStateRelease(const ProgramState *state);
    418 
    419   ProgramStateRef
    420   invalidateRegionsImpl(ArrayRef<const MemRegion *> Regions,
    421                         const Expr *E, unsigned BlockCount,
    422                         const LocationContext *LCtx,
    423                         bool ResultsInSymbolEscape,
    424                         InvalidatedSymbols &IS,
    425                         const CallEvent *Call) const;
    426 };
    427 
    428 //===----------------------------------------------------------------------===//
    429 // ProgramStateManager - Factory object for ProgramStates.
    430 //===----------------------------------------------------------------------===//
    431 
    432 class ProgramStateManager {
    433   friend class ProgramState;
    434   friend void ProgramStateRelease(const ProgramState *state);
    435 private:
    436   /// Eng - The SubEngine that owns this state manager.
    437   SubEngine *Eng; /* Can be null. */
    438 
    439   EnvironmentManager                   EnvMgr;
    440   OwningPtr<StoreManager>              StoreMgr;
    441   OwningPtr<ConstraintManager>         ConstraintMgr;
    442 
    443   ProgramState::GenericDataMap::Factory     GDMFactory;
    444 
    445   typedef llvm::DenseMap<void*,std::pair<void*,void (*)(void*)> > GDMContextsTy;
    446   GDMContextsTy GDMContexts;
    447 
    448   /// StateSet - FoldingSet containing all the states created for analyzing
    449   ///  a particular function.  This is used to unique states.
    450   llvm::FoldingSet<ProgramState> StateSet;
    451 
    452   /// Object that manages the data for all created SVals.
    453   OwningPtr<SValBuilder> svalBuilder;
    454 
    455   /// Manages memory for created CallEvents.
    456   OwningPtr<CallEventManager> CallEventMgr;
    457 
    458   /// A BumpPtrAllocator to allocate states.
    459   llvm::BumpPtrAllocator &Alloc;
    460 
    461   /// A vector of ProgramStates that we can reuse.
    462   std::vector<ProgramState *> freeStates;
    463 
    464 public:
    465   ProgramStateManager(ASTContext &Ctx,
    466                  StoreManagerCreator CreateStoreManager,
    467                  ConstraintManagerCreator CreateConstraintManager,
    468                  llvm::BumpPtrAllocator& alloc,
    469                  SubEngine *subeng);
    470 
    471   ~ProgramStateManager();
    472 
    473   ProgramStateRef getInitialState(const LocationContext *InitLoc);
    474 
    475   ASTContext &getContext() { return svalBuilder->getContext(); }
    476   const ASTContext &getContext() const { return svalBuilder->getContext(); }
    477 
    478   BasicValueFactory &getBasicVals() {
    479     return svalBuilder->getBasicValueFactory();
    480   }
    481 
    482   SValBuilder &getSValBuilder() {
    483     return *svalBuilder;
    484   }
    485 
    486   SymbolManager &getSymbolManager() {
    487     return svalBuilder->getSymbolManager();
    488   }
    489   const SymbolManager &getSymbolManager() const {
    490     return svalBuilder->getSymbolManager();
    491   }
    492 
    493   llvm::BumpPtrAllocator& getAllocator() { return Alloc; }
    494 
    495   MemRegionManager& getRegionManager() {
    496     return svalBuilder->getRegionManager();
    497   }
    498   const MemRegionManager& getRegionManager() const {
    499     return svalBuilder->getRegionManager();
    500   }
    501 
    502   CallEventManager &getCallEventManager() { return *CallEventMgr; }
    503 
    504   StoreManager& getStoreManager() { return *StoreMgr; }
    505   ConstraintManager& getConstraintManager() { return *ConstraintMgr; }
    506   SubEngine* getOwningEngine() { return Eng; }
    507 
    508   ProgramStateRef removeDeadBindings(ProgramStateRef St,
    509                                     const StackFrameContext *LCtx,
    510                                     SymbolReaper& SymReaper);
    511 
    512 public:
    513 
    514   SVal ArrayToPointer(Loc Array) {
    515     return StoreMgr->ArrayToPointer(Array);
    516   }
    517 
    518   // Methods that manipulate the GDM.
    519   ProgramStateRef addGDM(ProgramStateRef St, void *Key, void *Data);
    520   ProgramStateRef removeGDM(ProgramStateRef state, void *Key);
    521 
    522   // Methods that query & manipulate the Store.
    523 
    524   void iterBindings(ProgramStateRef state, StoreManager::BindingsHandler& F) {
    525     StoreMgr->iterBindings(state->getStore(), F);
    526   }
    527 
    528   ProgramStateRef getPersistentState(ProgramState &Impl);
    529   ProgramStateRef getPersistentStateWithGDM(ProgramStateRef FromState,
    530                                            ProgramStateRef GDMState);
    531 
    532   bool haveEqualEnvironments(ProgramStateRef S1, ProgramStateRef S2) {
    533     return S1->Env == S2->Env;
    534   }
    535 
    536   bool haveEqualStores(ProgramStateRef S1, ProgramStateRef S2) {
    537     return S1->store == S2->store;
    538   }
    539 
    540   //==---------------------------------------------------------------------==//
    541   // Generic Data Map methods.
    542   //==---------------------------------------------------------------------==//
    543   //
    544   // ProgramStateManager and ProgramState support a "generic data map" that allows
    545   // different clients of ProgramState objects to embed arbitrary data within a
    546   // ProgramState object.  The generic data map is essentially an immutable map
    547   // from a "tag" (that acts as the "key" for a client) and opaque values.
    548   // Tags/keys and values are simply void* values.  The typical way that clients
    549   // generate unique tags are by taking the address of a static variable.
    550   // Clients are responsible for ensuring that data values referred to by a
    551   // the data pointer are immutable (and thus are essentially purely functional
    552   // data).
    553   //
    554   // The templated methods below use the ProgramStateTrait<T> class
    555   // to resolve keys into the GDM and to return data values to clients.
    556   //
    557 
    558   // Trait based GDM dispatch.
    559   template <typename T>
    560   ProgramStateRef set(ProgramStateRef st, typename ProgramStateTrait<T>::data_type D) {
    561     return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
    562                   ProgramStateTrait<T>::MakeVoidPtr(D));
    563   }
    564 
    565   template<typename T>
    566   ProgramStateRef set(ProgramStateRef st,
    567                      typename ProgramStateTrait<T>::key_type K,
    568                      typename ProgramStateTrait<T>::value_type V,
    569                      typename ProgramStateTrait<T>::context_type C) {
    570 
    571     return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
    572      ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Set(st->get<T>(), K, V, C)));
    573   }
    574 
    575   template <typename T>
    576   ProgramStateRef add(ProgramStateRef st,
    577                      typename ProgramStateTrait<T>::key_type K,
    578                      typename ProgramStateTrait<T>::context_type C) {
    579     return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
    580         ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Add(st->get<T>(), K, C)));
    581   }
    582 
    583   template <typename T>
    584   ProgramStateRef remove(ProgramStateRef st,
    585                         typename ProgramStateTrait<T>::key_type K,
    586                         typename ProgramStateTrait<T>::context_type C) {
    587 
    588     return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
    589      ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Remove(st->get<T>(), K, C)));
    590   }
    591 
    592   template <typename T>
    593   ProgramStateRef remove(ProgramStateRef st) {
    594     return removeGDM(st, ProgramStateTrait<T>::GDMIndex());
    595   }
    596 
    597   void *FindGDMContext(void *index,
    598                        void *(*CreateContext)(llvm::BumpPtrAllocator&),
    599                        void  (*DeleteContext)(void*));
    600 
    601   template <typename T>
    602   typename ProgramStateTrait<T>::context_type get_context() {
    603     void *p = FindGDMContext(ProgramStateTrait<T>::GDMIndex(),
    604                              ProgramStateTrait<T>::CreateContext,
    605                              ProgramStateTrait<T>::DeleteContext);
    606 
    607     return ProgramStateTrait<T>::MakeContext(p);
    608   }
    609 
    610   void EndPath(ProgramStateRef St) {
    611     ConstraintMgr->EndPath(St);
    612   }
    613 };
    614 
    615 
    616 //===----------------------------------------------------------------------===//
    617 // Out-of-line method definitions for ProgramState.
    618 //===----------------------------------------------------------------------===//
    619 
    620 inline ConstraintManager &ProgramState::getConstraintManager() const {
    621   return stateMgr->getConstraintManager();
    622 }
    623 
    624 inline const VarRegion* ProgramState::getRegion(const VarDecl *D,
    625                                                 const LocationContext *LC) const
    626 {
    627   return getStateManager().getRegionManager().getVarRegion(D, LC);
    628 }
    629 
    630 inline ProgramStateRef ProgramState::assume(DefinedOrUnknownSVal Cond,
    631                                       bool Assumption) const {
    632   if (Cond.isUnknown())
    633     return this;
    634 
    635   return getStateManager().ConstraintMgr
    636       ->assume(this, Cond.castAs<DefinedSVal>(), Assumption);
    637 }
    638 
    639 inline std::pair<ProgramStateRef , ProgramStateRef >
    640 ProgramState::assume(DefinedOrUnknownSVal Cond) const {
    641   if (Cond.isUnknown())
    642     return std::make_pair(this, this);
    643 
    644   return getStateManager().ConstraintMgr
    645       ->assumeDual(this, Cond.castAs<DefinedSVal>());
    646 }
    647 
    648 inline ProgramStateRef ProgramState::bindLoc(SVal LV, SVal V) const {
    649   if (Optional<Loc> L = LV.getAs<Loc>())
    650     return bindLoc(*L, V);
    651   return this;
    652 }
    653 
    654 inline Loc ProgramState::getLValue(const VarDecl *VD,
    655                                const LocationContext *LC) const {
    656   return getStateManager().StoreMgr->getLValueVar(VD, LC);
    657 }
    658 
    659 inline Loc ProgramState::getLValue(const CompoundLiteralExpr *literal,
    660                                const LocationContext *LC) const {
    661   return getStateManager().StoreMgr->getLValueCompoundLiteral(literal, LC);
    662 }
    663 
    664 inline SVal ProgramState::getLValue(const ObjCIvarDecl *D, SVal Base) const {
    665   return getStateManager().StoreMgr->getLValueIvar(D, Base);
    666 }
    667 
    668 inline SVal ProgramState::getLValue(const FieldDecl *D, SVal Base) const {
    669   return getStateManager().StoreMgr->getLValueField(D, Base);
    670 }
    671 
    672 inline SVal ProgramState::getLValue(const IndirectFieldDecl *D,
    673                                     SVal Base) const {
    674   StoreManager &SM = *getStateManager().StoreMgr;
    675   for (IndirectFieldDecl::chain_iterator I = D->chain_begin(),
    676                                          E = D->chain_end();
    677        I != E; ++I) {
    678     Base = SM.getLValueField(cast<FieldDecl>(*I), Base);
    679   }
    680 
    681   return Base;
    682 }
    683 
    684 inline SVal ProgramState::getLValue(QualType ElementType, SVal Idx, SVal Base) const{
    685   if (Optional<NonLoc> N = Idx.getAs<NonLoc>())
    686     return getStateManager().StoreMgr->getLValueElement(ElementType, *N, Base);
    687   return UnknownVal();
    688 }
    689 
    690 inline SVal ProgramState::getSVal(const Stmt *Ex,
    691                                   const LocationContext *LCtx) const{
    692   return Env.getSVal(EnvironmentEntry(Ex, LCtx),
    693                      *getStateManager().svalBuilder);
    694 }
    695 
    696 inline SVal
    697 ProgramState::getSValAsScalarOrLoc(const Stmt *S,
    698                                    const LocationContext *LCtx) const {
    699   if (const Expr *Ex = dyn_cast<Expr>(S)) {
    700     QualType T = Ex->getType();
    701     if (Ex->isGLValue() || Loc::isLocType(T) || T->isIntegerType())
    702       return getSVal(S, LCtx);
    703   }
    704 
    705   return UnknownVal();
    706 }
    707 
    708 inline SVal ProgramState::getRawSVal(Loc LV, QualType T) const {
    709   return getStateManager().StoreMgr->getBinding(getStore(), LV, T);
    710 }
    711 
    712 inline SVal ProgramState::getSVal(const MemRegion* R) const {
    713   return getStateManager().StoreMgr->getBinding(getStore(),
    714                                                 loc::MemRegionVal(R));
    715 }
    716 
    717 inline BasicValueFactory &ProgramState::getBasicVals() const {
    718   return getStateManager().getBasicVals();
    719 }
    720 
    721 inline SymbolManager &ProgramState::getSymbolManager() const {
    722   return getStateManager().getSymbolManager();
    723 }
    724 
    725 template<typename T>
    726 ProgramStateRef ProgramState::add(typename ProgramStateTrait<T>::key_type K) const {
    727   return getStateManager().add<T>(this, K, get_context<T>());
    728 }
    729 
    730 template <typename T>
    731 typename ProgramStateTrait<T>::context_type ProgramState::get_context() const {
    732   return getStateManager().get_context<T>();
    733 }
    734 
    735 template<typename T>
    736 ProgramStateRef ProgramState::remove(typename ProgramStateTrait<T>::key_type K) const {
    737   return getStateManager().remove<T>(this, K, get_context<T>());
    738 }
    739 
    740 template<typename T>
    741 ProgramStateRef ProgramState::remove(typename ProgramStateTrait<T>::key_type K,
    742                                typename ProgramStateTrait<T>::context_type C) const {
    743   return getStateManager().remove<T>(this, K, C);
    744 }
    745 
    746 template <typename T>
    747 ProgramStateRef ProgramState::remove() const {
    748   return getStateManager().remove<T>(this);
    749 }
    750 
    751 template<typename T>
    752 ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::data_type D) const {
    753   return getStateManager().set<T>(this, D);
    754 }
    755 
    756 template<typename T>
    757 ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::key_type K,
    758                             typename ProgramStateTrait<T>::value_type E) const {
    759   return getStateManager().set<T>(this, K, E, get_context<T>());
    760 }
    761 
    762 template<typename T>
    763 ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::key_type K,
    764                             typename ProgramStateTrait<T>::value_type E,
    765                             typename ProgramStateTrait<T>::context_type C) const {
    766   return getStateManager().set<T>(this, K, E, C);
    767 }
    768 
    769 template <typename CB>
    770 CB ProgramState::scanReachableSymbols(SVal val) const {
    771   CB cb(this);
    772   scanReachableSymbols(val, cb);
    773   return cb;
    774 }
    775 
    776 template <typename CB>
    777 CB ProgramState::scanReachableSymbols(const SVal *beg, const SVal *end) const {
    778   CB cb(this);
    779   scanReachableSymbols(beg, end, cb);
    780   return cb;
    781 }
    782 
    783 template <typename CB>
    784 CB ProgramState::scanReachableSymbols(const MemRegion * const *beg,
    785                                  const MemRegion * const *end) const {
    786   CB cb(this);
    787   scanReachableSymbols(beg, end, cb);
    788   return cb;
    789 }
    790 
    791 /// \class ScanReachableSymbols
    792 /// A Utility class that allows to visit the reachable symbols using a custom
    793 /// SymbolVisitor.
    794 class ScanReachableSymbols {
    795   typedef llvm::DenseMap<const void*, unsigned> VisitedItems;
    796 
    797   VisitedItems visited;
    798   ProgramStateRef state;
    799   SymbolVisitor &visitor;
    800 public:
    801 
    802   ScanReachableSymbols(ProgramStateRef st, SymbolVisitor& v)
    803     : state(st), visitor(v) {}
    804 
    805   bool scan(nonloc::CompoundVal val);
    806   bool scan(SVal val);
    807   bool scan(const MemRegion *R);
    808   bool scan(const SymExpr *sym);
    809 };
    810 
    811 } // end ento namespace
    812 
    813 } // end clang namespace
    814 
    815 #endif
    816