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_STATICANALYZER_CORE_PATHSENSITIVE_PROGRAMSTATE_H
15 #define LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_PROGRAMSTATE_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 #include "llvm/Support/Allocator.h"
29 
30 namespace llvm {
31 class APSInt;
32 }
33 
34 namespace clang {
35 class ASTContext;
36 
37 namespace ento {
38 
39 class CallEvent;
40 class CallEventManager;
41 
42 typedef std::unique_ptr<ConstraintManager>(*ConstraintManagerCreator)(
43     ProgramStateManager &, SubEngine *);
44 typedef std::unique_ptr<StoreManager>(*StoreManagerCreator)(
45     ProgramStateManager &);
46 
47 //===----------------------------------------------------------------------===//
48 // ProgramStateTrait - Traits used by the Generic Data Map of a ProgramState.
49 //===----------------------------------------------------------------------===//
50 
51 template <typename T> struct ProgramStatePartialTrait;
52 
53 template <typename T> struct ProgramStateTrait {
54   typedef typename T::data_type data_type;
MakeVoidPtrProgramStateTrait55   static inline void *MakeVoidPtr(data_type D) { return (void*) D; }
MakeDataProgramStateTrait56   static inline data_type MakeData(void *const* P) {
57     return P ? (data_type) *P : (data_type) 0;
58   }
59 };
60 
61 /// \class ProgramState
62 /// ProgramState - This class encapsulates:
63 ///
64 ///    1. A mapping from expressions to values (Environment)
65 ///    2. A mapping from locations to values (Store)
66 ///    3. Constraints on symbolic values (GenericDataMap)
67 ///
68 ///  Together these represent the "abstract state" of a program.
69 ///
70 ///  ProgramState is intended to be used as a functional object; that is,
71 ///  once it is created and made "persistent" in a FoldingSet, its
72 ///  values will never change.
73 class ProgramState : public llvm::FoldingSetNode {
74 public:
75   typedef llvm::ImmutableSet<llvm::APSInt*>                IntSetTy;
76   typedef llvm::ImmutableMap<void*, void*>                 GenericDataMap;
77 
78 private:
79   void operator=(const ProgramState& R) = delete;
80 
81   friend class ProgramStateManager;
82   friend class ExplodedGraph;
83   friend class ExplodedNode;
84 
85   ProgramStateManager *stateMgr;
86   Environment Env;           // Maps a Stmt to its current SVal.
87   Store store;               // Maps a location to its current value.
88   GenericDataMap   GDM;      // Custom data stored by a client of this class.
89   unsigned refCount;
90 
91   /// makeWithStore - Return a ProgramState with the same values as the current
92   ///  state with the exception of using the specified Store.
93   ProgramStateRef makeWithStore(const StoreRef &store) const;
94 
95   void setStore(const StoreRef &storeRef);
96 
97 public:
98   /// This ctor is used when creating the first ProgramState object.
99   ProgramState(ProgramStateManager *mgr, const Environment& env,
100           StoreRef st, GenericDataMap gdm);
101 
102   /// Copy ctor - We must explicitly define this or else the "Next" ptr
103   ///  in FoldingSetNode will also get copied.
104   ProgramState(const ProgramState &RHS);
105 
106   ~ProgramState();
107 
108   /// Return the ProgramStateManager associated with this state.
getStateManager()109   ProgramStateManager &getStateManager() const {
110     return *stateMgr;
111   }
112 
113   /// Return the ConstraintManager.
114   ConstraintManager &getConstraintManager() const;
115 
116   /// getEnvironment - Return the environment associated with this state.
117   ///  The environment is the mapping from expressions to values.
getEnvironment()118   const Environment& getEnvironment() const { return Env; }
119 
120   /// Return the store associated with this state.  The store
121   ///  is a mapping from locations to values.
getStore()122   Store getStore() const { return store; }
123 
124 
125   /// getGDM - Return the generic data map associated with this state.
getGDM()126   GenericDataMap getGDM() const { return GDM; }
127 
setGDM(GenericDataMap gdm)128   void setGDM(GenericDataMap gdm) { GDM = gdm; }
129 
130   /// Profile - Profile the contents of a ProgramState object for use in a
131   ///  FoldingSet.  Two ProgramState objects are considered equal if they
132   ///  have the same Environment, Store, and GenericDataMap.
Profile(llvm::FoldingSetNodeID & ID,const ProgramState * V)133   static void Profile(llvm::FoldingSetNodeID& ID, const ProgramState *V) {
134     V->Env.Profile(ID);
135     ID.AddPointer(V->store);
136     V->GDM.Profile(ID);
137   }
138 
139   /// Profile - Used to profile the contents of this object for inclusion
140   ///  in a FoldingSet.
Profile(llvm::FoldingSetNodeID & ID)141   void Profile(llvm::FoldingSetNodeID& ID) const {
142     Profile(ID, this);
143   }
144 
145   BasicValueFactory &getBasicVals() const;
146   SymbolManager &getSymbolManager() const;
147 
148   //==---------------------------------------------------------------------==//
149   // Constraints on values.
150   //==---------------------------------------------------------------------==//
151   //
152   // Each ProgramState records constraints on symbolic values.  These constraints
153   // are managed using the ConstraintManager associated with a ProgramStateManager.
154   // As constraints gradually accrue on symbolic values, added constraints
155   // may conflict and indicate that a state is infeasible (as no real values
156   // could satisfy all the constraints).  This is the principal mechanism
157   // for modeling path-sensitivity in ExprEngine/ProgramState.
158   //
159   // Various "assume" methods form the interface for adding constraints to
160   // symbolic values.  A call to 'assume' indicates an assumption being placed
161   // on one or symbolic values.  'assume' methods take the following inputs:
162   //
163   //  (1) A ProgramState object representing the current state.
164   //
165   //  (2) The assumed constraint (which is specific to a given "assume" method).
166   //
167   //  (3) A binary value "Assumption" that indicates whether the constraint is
168   //      assumed to be true or false.
169   //
170   // The output of "assume*" is a new ProgramState object with the added constraints.
171   // If no new state is feasible, NULL is returned.
172   //
173 
174   /// Assumes that the value of \p cond is zero (if \p assumption is "false")
175   /// or non-zero (if \p assumption is "true").
176   ///
177   /// This returns a new state with the added constraint on \p cond.
178   /// If no new state is feasible, NULL is returned.
179   ProgramStateRef assume(DefinedOrUnknownSVal cond, bool assumption) const;
180 
181   /// Assumes both "true" and "false" for \p cond, and returns both
182   /// corresponding states (respectively).
183   ///
184   /// This is more efficient than calling assume() twice. Note that one (but not
185   /// both) of the returned states may be NULL.
186   std::pair<ProgramStateRef, ProgramStateRef>
187   assume(DefinedOrUnknownSVal cond) const;
188 
189   ProgramStateRef assumeInBound(DefinedOrUnknownSVal idx,
190                                DefinedOrUnknownSVal upperBound,
191                                bool assumption,
192                                QualType IndexType = QualType()) const;
193 
194   /// Assumes that the value of \p Val is bounded with [\p From; \p To]
195   /// (if \p assumption is "true") or it is fully out of this range
196   /// (if \p assumption is "false").
197   ///
198   /// This returns a new state with the added constraint on \p cond.
199   /// If no new state is feasible, NULL is returned.
200   ProgramStateRef assumeWithinInclusiveRange(DefinedOrUnknownSVal Val,
201                                              const llvm::APSInt &From,
202                                              const llvm::APSInt &To,
203                                              bool assumption) const;
204 
205   /// Assumes given range both "true" and "false" for \p Val, and returns both
206   /// corresponding states (respectively).
207   ///
208   /// This is more efficient than calling assume() twice. Note that one (but not
209   /// both) of the returned states may be NULL.
210   std::pair<ProgramStateRef, ProgramStateRef>
211   assumeWithinInclusiveRange(DefinedOrUnknownSVal Val, const llvm::APSInt &From,
212                              const llvm::APSInt &To) const;
213 
214 
215   /// \brief Check if the given SVal is constrained to zero or is a zero
216   ///        constant.
217   ConditionTruthVal isNull(SVal V) const;
218 
219   /// Utility method for getting regions.
220   const VarRegion* getRegion(const VarDecl *D, const LocationContext *LC) const;
221 
222   //==---------------------------------------------------------------------==//
223   // Binding and retrieving values to/from the environment and symbolic store.
224   //==---------------------------------------------------------------------==//
225 
226   /// Create a new state by binding the value 'V' to the statement 'S' in the
227   /// state's environment.
228   ProgramStateRef BindExpr(const Stmt *S, const LocationContext *LCtx,
229                                SVal V, bool Invalidate = true) const;
230 
231   ProgramStateRef bindLoc(Loc location,
232                           SVal V,
233                           bool notifyChanges = true) const;
234 
235   ProgramStateRef bindLoc(SVal location, SVal V) const;
236 
237   ProgramStateRef bindDefault(SVal loc, SVal V) const;
238 
239   ProgramStateRef killBinding(Loc LV) const;
240 
241   /// \brief Returns the state with bindings for the given regions
242   ///  cleared from the store.
243   ///
244   /// Optionally invalidates global regions as well.
245   ///
246   /// \param Regions the set of regions to be invalidated.
247   /// \param E the expression that caused the invalidation.
248   /// \param BlockCount The number of times the current basic block has been
249   //         visited.
250   /// \param CausesPointerEscape the flag is set to true when
251   ///        the invalidation entails escape of a symbol (representing a
252   ///        pointer). For example, due to it being passed as an argument in a
253   ///        call.
254   /// \param IS the set of invalidated symbols.
255   /// \param Call if non-null, the invalidated regions represent parameters to
256   ///        the call and should be considered directly invalidated.
257   /// \param ITraits information about special handling for a particular
258   ///        region/symbol.
259   ProgramStateRef
260   invalidateRegions(ArrayRef<const MemRegion *> Regions, const Expr *E,
261                     unsigned BlockCount, const LocationContext *LCtx,
262                     bool CausesPointerEscape, InvalidatedSymbols *IS = nullptr,
263                     const CallEvent *Call = nullptr,
264                     RegionAndSymbolInvalidationTraits *ITraits = nullptr) const;
265 
266   ProgramStateRef
267   invalidateRegions(ArrayRef<SVal> Regions, const Expr *E,
268                     unsigned BlockCount, const LocationContext *LCtx,
269                     bool CausesPointerEscape, InvalidatedSymbols *IS = nullptr,
270                     const CallEvent *Call = nullptr,
271                     RegionAndSymbolInvalidationTraits *ITraits = nullptr) const;
272 
273   /// enterStackFrame - Returns the state for entry to the given stack frame,
274   ///  preserving the current state.
275   ProgramStateRef enterStackFrame(const CallEvent &Call,
276                                   const StackFrameContext *CalleeCtx) const;
277 
278   /// Get the lvalue for a variable reference.
279   Loc getLValue(const VarDecl *D, const LocationContext *LC) const;
280 
281   Loc getLValue(const CompoundLiteralExpr *literal,
282                 const LocationContext *LC) const;
283 
284   /// Get the lvalue for an ivar reference.
285   SVal getLValue(const ObjCIvarDecl *decl, SVal base) const;
286 
287   /// Get the lvalue for a field reference.
288   SVal getLValue(const FieldDecl *decl, SVal Base) const;
289 
290   /// Get the lvalue for an indirect field reference.
291   SVal getLValue(const IndirectFieldDecl *decl, SVal Base) const;
292 
293   /// Get the lvalue for an array index.
294   SVal getLValue(QualType ElementType, SVal Idx, SVal Base) const;
295 
296   /// Returns the SVal bound to the statement 'S' in the state's environment.
297   SVal getSVal(const Stmt *S, const LocationContext *LCtx) const;
298 
299   SVal getSValAsScalarOrLoc(const Stmt *Ex, const LocationContext *LCtx) const;
300 
301   /// \brief Return the value bound to the specified location.
302   /// Returns UnknownVal() if none found.
303   SVal getSVal(Loc LV, QualType T = QualType()) const;
304 
305   /// Returns the "raw" SVal bound to LV before any value simplfication.
306   SVal getRawSVal(Loc LV, QualType T= QualType()) const;
307 
308   /// \brief Return the value bound to the specified location.
309   /// Returns UnknownVal() if none found.
310   SVal getSVal(const MemRegion* R) const;
311 
312   SVal getSValAsScalarOrLoc(const MemRegion *R) const;
313 
314   /// \brief Visits the symbols reachable from the given SVal using the provided
315   /// SymbolVisitor.
316   ///
317   /// This is a convenience API. Consider using ScanReachableSymbols class
318   /// directly when making multiple scans on the same state with the same
319   /// visitor to avoid repeated initialization cost.
320   /// \sa ScanReachableSymbols
321   bool scanReachableSymbols(SVal val, SymbolVisitor& visitor) const;
322 
323   /// \brief Visits the symbols reachable from the SVals in the given range
324   /// using the provided SymbolVisitor.
325   bool scanReachableSymbols(const SVal *I, const SVal *E,
326                             SymbolVisitor &visitor) const;
327 
328   /// \brief Visits the symbols reachable from the regions in the given
329   /// MemRegions range using the provided SymbolVisitor.
330   bool scanReachableSymbols(const MemRegion * const *I,
331                             const MemRegion * const *E,
332                             SymbolVisitor &visitor) const;
333 
334   template <typename CB> CB scanReachableSymbols(SVal val) const;
335   template <typename CB> CB scanReachableSymbols(const SVal *beg,
336                                                  const SVal *end) const;
337 
338   template <typename CB> CB
339   scanReachableSymbols(const MemRegion * const *beg,
340                        const MemRegion * const *end) const;
341 
342   /// Create a new state in which the statement is marked as tainted.
343   ProgramStateRef addTaint(const Stmt *S, const LocationContext *LCtx,
344                                TaintTagType Kind = TaintTagGeneric) const;
345 
346   /// Create a new state in which the symbol is marked as tainted.
347   ProgramStateRef addTaint(SymbolRef S,
348                                TaintTagType Kind = TaintTagGeneric) const;
349 
350   /// Create a new state in which the region symbol is marked as tainted.
351   ProgramStateRef addTaint(const MemRegion *R,
352                                TaintTagType Kind = TaintTagGeneric) const;
353 
354   /// Check if the statement is tainted in the current state.
355   bool isTainted(const Stmt *S, const LocationContext *LCtx,
356                  TaintTagType Kind = TaintTagGeneric) const;
357   bool isTainted(SVal V, TaintTagType Kind = TaintTagGeneric) const;
358   bool isTainted(SymbolRef Sym, TaintTagType Kind = TaintTagGeneric) const;
359   bool isTainted(const MemRegion *Reg, TaintTagType Kind=TaintTagGeneric) const;
360 
361   //==---------------------------------------------------------------------==//
362   // Accessing the Generic Data Map (GDM).
363   //==---------------------------------------------------------------------==//
364 
365   void *const* FindGDM(void *K) const;
366 
367   template<typename T>
368   ProgramStateRef add(typename ProgramStateTrait<T>::key_type K) const;
369 
370   template <typename T>
371   typename ProgramStateTrait<T>::data_type
get()372   get() const {
373     return ProgramStateTrait<T>::MakeData(FindGDM(ProgramStateTrait<T>::GDMIndex()));
374   }
375 
376   template<typename T>
377   typename ProgramStateTrait<T>::lookup_type
get(typename ProgramStateTrait<T>::key_type key)378   get(typename ProgramStateTrait<T>::key_type key) const {
379     void *const* d = FindGDM(ProgramStateTrait<T>::GDMIndex());
380     return ProgramStateTrait<T>::Lookup(ProgramStateTrait<T>::MakeData(d), key);
381   }
382 
383   template <typename T>
384   typename ProgramStateTrait<T>::context_type get_context() const;
385 
386 
387   template<typename T>
388   ProgramStateRef remove(typename ProgramStateTrait<T>::key_type K) const;
389 
390   template<typename T>
391   ProgramStateRef remove(typename ProgramStateTrait<T>::key_type K,
392                         typename ProgramStateTrait<T>::context_type C) const;
393   template <typename T>
394   ProgramStateRef remove() const;
395 
396   template<typename T>
397   ProgramStateRef set(typename ProgramStateTrait<T>::data_type D) const;
398 
399   template<typename T>
400   ProgramStateRef set(typename ProgramStateTrait<T>::key_type K,
401                      typename ProgramStateTrait<T>::value_type E) const;
402 
403   template<typename T>
404   ProgramStateRef set(typename ProgramStateTrait<T>::key_type K,
405                      typename ProgramStateTrait<T>::value_type E,
406                      typename ProgramStateTrait<T>::context_type C) const;
407 
408   template<typename T>
contains(typename ProgramStateTrait<T>::key_type key)409   bool contains(typename ProgramStateTrait<T>::key_type key) const {
410     void *const* d = FindGDM(ProgramStateTrait<T>::GDMIndex());
411     return ProgramStateTrait<T>::Contains(ProgramStateTrait<T>::MakeData(d), key);
412   }
413 
414   // Pretty-printing.
415   void print(raw_ostream &Out, const char *nl = "\n",
416              const char *sep = "") const;
417   void printDOT(raw_ostream &Out) const;
418   void printTaint(raw_ostream &Out, const char *nl = "\n",
419                   const char *sep = "") const;
420 
421   void dump() const;
422   void dumpTaint() const;
423 
424 private:
425   friend void ProgramStateRetain(const ProgramState *state);
426   friend void ProgramStateRelease(const ProgramState *state);
427 
428   /// \sa invalidateValues()
429   /// \sa invalidateRegions()
430   ProgramStateRef
431   invalidateRegionsImpl(ArrayRef<SVal> Values,
432                         const Expr *E, unsigned BlockCount,
433                         const LocationContext *LCtx,
434                         bool ResultsInSymbolEscape,
435                         InvalidatedSymbols *IS,
436                         RegionAndSymbolInvalidationTraits *HTraits,
437                         const CallEvent *Call) const;
438 };
439 
440 //===----------------------------------------------------------------------===//
441 // ProgramStateManager - Factory object for ProgramStates.
442 //===----------------------------------------------------------------------===//
443 
444 class ProgramStateManager {
445   friend class ProgramState;
446   friend void ProgramStateRelease(const ProgramState *state);
447 private:
448   /// Eng - The SubEngine that owns this state manager.
449   SubEngine *Eng; /* Can be null. */
450 
451   EnvironmentManager                   EnvMgr;
452   std::unique_ptr<StoreManager>        StoreMgr;
453   std::unique_ptr<ConstraintManager>   ConstraintMgr;
454 
455   ProgramState::GenericDataMap::Factory     GDMFactory;
456 
457   typedef llvm::DenseMap<void*,std::pair<void*,void (*)(void*)> > GDMContextsTy;
458   GDMContextsTy GDMContexts;
459 
460   /// StateSet - FoldingSet containing all the states created for analyzing
461   ///  a particular function.  This is used to unique states.
462   llvm::FoldingSet<ProgramState> StateSet;
463 
464   /// Object that manages the data for all created SVals.
465   std::unique_ptr<SValBuilder> svalBuilder;
466 
467   /// Manages memory for created CallEvents.
468   std::unique_ptr<CallEventManager> CallEventMgr;
469 
470   /// A BumpPtrAllocator to allocate states.
471   llvm::BumpPtrAllocator &Alloc;
472 
473   /// A vector of ProgramStates that we can reuse.
474   std::vector<ProgramState *> freeStates;
475 
476 public:
477   ProgramStateManager(ASTContext &Ctx,
478                  StoreManagerCreator CreateStoreManager,
479                  ConstraintManagerCreator CreateConstraintManager,
480                  llvm::BumpPtrAllocator& alloc,
481                  SubEngine *subeng);
482 
483   ~ProgramStateManager();
484 
485   ProgramStateRef getInitialState(const LocationContext *InitLoc);
486 
getContext()487   ASTContext &getContext() { return svalBuilder->getContext(); }
getContext()488   const ASTContext &getContext() const { return svalBuilder->getContext(); }
489 
getBasicVals()490   BasicValueFactory &getBasicVals() {
491     return svalBuilder->getBasicValueFactory();
492   }
493 
getSValBuilder()494   SValBuilder &getSValBuilder() {
495     return *svalBuilder;
496   }
497 
getSymbolManager()498   SymbolManager &getSymbolManager() {
499     return svalBuilder->getSymbolManager();
500   }
getSymbolManager()501   const SymbolManager &getSymbolManager() const {
502     return svalBuilder->getSymbolManager();
503   }
504 
getAllocator()505   llvm::BumpPtrAllocator& getAllocator() { return Alloc; }
506 
getRegionManager()507   MemRegionManager& getRegionManager() {
508     return svalBuilder->getRegionManager();
509   }
getRegionManager()510   const MemRegionManager& getRegionManager() const {
511     return svalBuilder->getRegionManager();
512   }
513 
getCallEventManager()514   CallEventManager &getCallEventManager() { return *CallEventMgr; }
515 
getStoreManager()516   StoreManager& getStoreManager() { return *StoreMgr; }
getConstraintManager()517   ConstraintManager& getConstraintManager() { return *ConstraintMgr; }
getOwningEngine()518   SubEngine* getOwningEngine() { return Eng; }
519 
520   ProgramStateRef removeDeadBindings(ProgramStateRef St,
521                                     const StackFrameContext *LCtx,
522                                     SymbolReaper& SymReaper);
523 
524 public:
525 
ArrayToPointer(Loc Array,QualType ElementTy)526   SVal ArrayToPointer(Loc Array, QualType ElementTy) {
527     return StoreMgr->ArrayToPointer(Array, ElementTy);
528   }
529 
530   // Methods that manipulate the GDM.
531   ProgramStateRef addGDM(ProgramStateRef St, void *Key, void *Data);
532   ProgramStateRef removeGDM(ProgramStateRef state, void *Key);
533 
534   // Methods that query & manipulate the Store.
535 
iterBindings(ProgramStateRef state,StoreManager::BindingsHandler & F)536   void iterBindings(ProgramStateRef state, StoreManager::BindingsHandler& F) {
537     StoreMgr->iterBindings(state->getStore(), F);
538   }
539 
540   ProgramStateRef getPersistentState(ProgramState &Impl);
541   ProgramStateRef getPersistentStateWithGDM(ProgramStateRef FromState,
542                                            ProgramStateRef GDMState);
543 
haveEqualEnvironments(ProgramStateRef S1,ProgramStateRef S2)544   bool haveEqualEnvironments(ProgramStateRef S1, ProgramStateRef S2) {
545     return S1->Env == S2->Env;
546   }
547 
haveEqualStores(ProgramStateRef S1,ProgramStateRef S2)548   bool haveEqualStores(ProgramStateRef S1, ProgramStateRef S2) {
549     return S1->store == S2->store;
550   }
551 
552   //==---------------------------------------------------------------------==//
553   // Generic Data Map methods.
554   //==---------------------------------------------------------------------==//
555   //
556   // ProgramStateManager and ProgramState support a "generic data map" that allows
557   // different clients of ProgramState objects to embed arbitrary data within a
558   // ProgramState object.  The generic data map is essentially an immutable map
559   // from a "tag" (that acts as the "key" for a client) and opaque values.
560   // Tags/keys and values are simply void* values.  The typical way that clients
561   // generate unique tags are by taking the address of a static variable.
562   // Clients are responsible for ensuring that data values referred to by a
563   // the data pointer are immutable (and thus are essentially purely functional
564   // data).
565   //
566   // The templated methods below use the ProgramStateTrait<T> class
567   // to resolve keys into the GDM and to return data values to clients.
568   //
569 
570   // Trait based GDM dispatch.
571   template <typename T>
set(ProgramStateRef st,typename ProgramStateTrait<T>::data_type D)572   ProgramStateRef set(ProgramStateRef st, typename ProgramStateTrait<T>::data_type D) {
573     return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
574                   ProgramStateTrait<T>::MakeVoidPtr(D));
575   }
576 
577   template<typename T>
set(ProgramStateRef st,typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::value_type V,typename ProgramStateTrait<T>::context_type C)578   ProgramStateRef set(ProgramStateRef st,
579                      typename ProgramStateTrait<T>::key_type K,
580                      typename ProgramStateTrait<T>::value_type V,
581                      typename ProgramStateTrait<T>::context_type C) {
582 
583     return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
584      ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Set(st->get<T>(), K, V, C)));
585   }
586 
587   template <typename T>
add(ProgramStateRef st,typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::context_type C)588   ProgramStateRef add(ProgramStateRef st,
589                      typename ProgramStateTrait<T>::key_type K,
590                      typename ProgramStateTrait<T>::context_type C) {
591     return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
592         ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Add(st->get<T>(), K, C)));
593   }
594 
595   template <typename T>
remove(ProgramStateRef st,typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::context_type C)596   ProgramStateRef remove(ProgramStateRef st,
597                         typename ProgramStateTrait<T>::key_type K,
598                         typename ProgramStateTrait<T>::context_type C) {
599 
600     return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
601      ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Remove(st->get<T>(), K, C)));
602   }
603 
604   template <typename T>
remove(ProgramStateRef st)605   ProgramStateRef remove(ProgramStateRef st) {
606     return removeGDM(st, ProgramStateTrait<T>::GDMIndex());
607   }
608 
609   void *FindGDMContext(void *index,
610                        void *(*CreateContext)(llvm::BumpPtrAllocator&),
611                        void  (*DeleteContext)(void*));
612 
613   template <typename T>
get_context()614   typename ProgramStateTrait<T>::context_type get_context() {
615     void *p = FindGDMContext(ProgramStateTrait<T>::GDMIndex(),
616                              ProgramStateTrait<T>::CreateContext,
617                              ProgramStateTrait<T>::DeleteContext);
618 
619     return ProgramStateTrait<T>::MakeContext(p);
620   }
621 
EndPath(ProgramStateRef St)622   void EndPath(ProgramStateRef St) {
623     ConstraintMgr->EndPath(St);
624   }
625 };
626 
627 
628 //===----------------------------------------------------------------------===//
629 // Out-of-line method definitions for ProgramState.
630 //===----------------------------------------------------------------------===//
631 
getConstraintManager()632 inline ConstraintManager &ProgramState::getConstraintManager() const {
633   return stateMgr->getConstraintManager();
634 }
635 
getRegion(const VarDecl * D,const LocationContext * LC)636 inline const VarRegion* ProgramState::getRegion(const VarDecl *D,
637                                                 const LocationContext *LC) const
638 {
639   return getStateManager().getRegionManager().getVarRegion(D, LC);
640 }
641 
assume(DefinedOrUnknownSVal Cond,bool Assumption)642 inline ProgramStateRef ProgramState::assume(DefinedOrUnknownSVal Cond,
643                                       bool Assumption) const {
644   if (Cond.isUnknown())
645     return this;
646 
647   return getStateManager().ConstraintMgr
648       ->assume(this, Cond.castAs<DefinedSVal>(), Assumption);
649 }
650 
651 inline std::pair<ProgramStateRef , ProgramStateRef >
assume(DefinedOrUnknownSVal Cond)652 ProgramState::assume(DefinedOrUnknownSVal Cond) const {
653   if (Cond.isUnknown())
654     return std::make_pair(this, this);
655 
656   return getStateManager().ConstraintMgr
657       ->assumeDual(this, Cond.castAs<DefinedSVal>());
658 }
659 
660 inline ProgramStateRef
assumeWithinInclusiveRange(DefinedOrUnknownSVal Val,const llvm::APSInt & From,const llvm::APSInt & To,bool Assumption)661 ProgramState::assumeWithinInclusiveRange(DefinedOrUnknownSVal Val,
662                                          const llvm::APSInt &From,
663                                          const llvm::APSInt &To,
664                                          bool Assumption) const {
665   if (Val.isUnknown())
666     return this;
667 
668   assert(Val.getAs<NonLoc>() && "Only NonLocs are supported!");
669 
670   return getStateManager().ConstraintMgr->assumeWithinInclusiveRange(
671         this, Val.castAs<NonLoc>(), From, To, Assumption);
672 }
673 
674 inline std::pair<ProgramStateRef, ProgramStateRef>
assumeWithinInclusiveRange(DefinedOrUnknownSVal Val,const llvm::APSInt & From,const llvm::APSInt & To)675 ProgramState::assumeWithinInclusiveRange(DefinedOrUnknownSVal Val,
676                                          const llvm::APSInt &From,
677                                          const llvm::APSInt &To) const {
678   if (Val.isUnknown())
679     return std::make_pair(this, this);
680 
681   assert(Val.getAs<NonLoc>() && "Only NonLocs are supported!");
682 
683   return getStateManager().ConstraintMgr
684       ->assumeWithinInclusiveRangeDual(this, Val.castAs<NonLoc>(), From, To);
685 }
686 
bindLoc(SVal LV,SVal V)687 inline ProgramStateRef ProgramState::bindLoc(SVal LV, SVal V) const {
688   if (Optional<Loc> L = LV.getAs<Loc>())
689     return bindLoc(*L, V);
690   return this;
691 }
692 
getLValue(const VarDecl * VD,const LocationContext * LC)693 inline Loc ProgramState::getLValue(const VarDecl *VD,
694                                const LocationContext *LC) const {
695   return getStateManager().StoreMgr->getLValueVar(VD, LC);
696 }
697 
getLValue(const CompoundLiteralExpr * literal,const LocationContext * LC)698 inline Loc ProgramState::getLValue(const CompoundLiteralExpr *literal,
699                                const LocationContext *LC) const {
700   return getStateManager().StoreMgr->getLValueCompoundLiteral(literal, LC);
701 }
702 
getLValue(const ObjCIvarDecl * D,SVal Base)703 inline SVal ProgramState::getLValue(const ObjCIvarDecl *D, SVal Base) const {
704   return getStateManager().StoreMgr->getLValueIvar(D, Base);
705 }
706 
getLValue(const FieldDecl * D,SVal Base)707 inline SVal ProgramState::getLValue(const FieldDecl *D, SVal Base) const {
708   return getStateManager().StoreMgr->getLValueField(D, Base);
709 }
710 
getLValue(const IndirectFieldDecl * D,SVal Base)711 inline SVal ProgramState::getLValue(const IndirectFieldDecl *D,
712                                     SVal Base) const {
713   StoreManager &SM = *getStateManager().StoreMgr;
714   for (const auto *I : D->chain()) {
715     Base = SM.getLValueField(cast<FieldDecl>(I), Base);
716   }
717 
718   return Base;
719 }
720 
getLValue(QualType ElementType,SVal Idx,SVal Base)721 inline SVal ProgramState::getLValue(QualType ElementType, SVal Idx, SVal Base) const{
722   if (Optional<NonLoc> N = Idx.getAs<NonLoc>())
723     return getStateManager().StoreMgr->getLValueElement(ElementType, *N, Base);
724   return UnknownVal();
725 }
726 
getSVal(const Stmt * Ex,const LocationContext * LCtx)727 inline SVal ProgramState::getSVal(const Stmt *Ex,
728                                   const LocationContext *LCtx) const{
729   return Env.getSVal(EnvironmentEntry(Ex, LCtx),
730                      *getStateManager().svalBuilder);
731 }
732 
733 inline SVal
getSValAsScalarOrLoc(const Stmt * S,const LocationContext * LCtx)734 ProgramState::getSValAsScalarOrLoc(const Stmt *S,
735                                    const LocationContext *LCtx) const {
736   if (const Expr *Ex = dyn_cast<Expr>(S)) {
737     QualType T = Ex->getType();
738     if (Ex->isGLValue() || Loc::isLocType(T) ||
739         T->isIntegralOrEnumerationType())
740       return getSVal(S, LCtx);
741   }
742 
743   return UnknownVal();
744 }
745 
getRawSVal(Loc LV,QualType T)746 inline SVal ProgramState::getRawSVal(Loc LV, QualType T) const {
747   return getStateManager().StoreMgr->getBinding(getStore(), LV, T);
748 }
749 
getSVal(const MemRegion * R)750 inline SVal ProgramState::getSVal(const MemRegion* R) const {
751   return getStateManager().StoreMgr->getBinding(getStore(),
752                                                 loc::MemRegionVal(R));
753 }
754 
getBasicVals()755 inline BasicValueFactory &ProgramState::getBasicVals() const {
756   return getStateManager().getBasicVals();
757 }
758 
getSymbolManager()759 inline SymbolManager &ProgramState::getSymbolManager() const {
760   return getStateManager().getSymbolManager();
761 }
762 
763 template<typename T>
add(typename ProgramStateTrait<T>::key_type K)764 ProgramStateRef ProgramState::add(typename ProgramStateTrait<T>::key_type K) const {
765   return getStateManager().add<T>(this, K, get_context<T>());
766 }
767 
768 template <typename T>
get_context()769 typename ProgramStateTrait<T>::context_type ProgramState::get_context() const {
770   return getStateManager().get_context<T>();
771 }
772 
773 template<typename T>
remove(typename ProgramStateTrait<T>::key_type K)774 ProgramStateRef ProgramState::remove(typename ProgramStateTrait<T>::key_type K) const {
775   return getStateManager().remove<T>(this, K, get_context<T>());
776 }
777 
778 template<typename T>
remove(typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::context_type C)779 ProgramStateRef ProgramState::remove(typename ProgramStateTrait<T>::key_type K,
780                                typename ProgramStateTrait<T>::context_type C) const {
781   return getStateManager().remove<T>(this, K, C);
782 }
783 
784 template <typename T>
remove()785 ProgramStateRef ProgramState::remove() const {
786   return getStateManager().remove<T>(this);
787 }
788 
789 template<typename T>
set(typename ProgramStateTrait<T>::data_type D)790 ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::data_type D) const {
791   return getStateManager().set<T>(this, D);
792 }
793 
794 template<typename T>
set(typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::value_type E)795 ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::key_type K,
796                             typename ProgramStateTrait<T>::value_type E) const {
797   return getStateManager().set<T>(this, K, E, get_context<T>());
798 }
799 
800 template<typename T>
set(typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::value_type E,typename ProgramStateTrait<T>::context_type C)801 ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::key_type K,
802                             typename ProgramStateTrait<T>::value_type E,
803                             typename ProgramStateTrait<T>::context_type C) const {
804   return getStateManager().set<T>(this, K, E, C);
805 }
806 
807 template <typename CB>
scanReachableSymbols(SVal val)808 CB ProgramState::scanReachableSymbols(SVal val) const {
809   CB cb(this);
810   scanReachableSymbols(val, cb);
811   return cb;
812 }
813 
814 template <typename CB>
scanReachableSymbols(const SVal * beg,const SVal * end)815 CB ProgramState::scanReachableSymbols(const SVal *beg, const SVal *end) const {
816   CB cb(this);
817   scanReachableSymbols(beg, end, cb);
818   return cb;
819 }
820 
821 template <typename CB>
scanReachableSymbols(const MemRegion * const * beg,const MemRegion * const * end)822 CB ProgramState::scanReachableSymbols(const MemRegion * const *beg,
823                                  const MemRegion * const *end) const {
824   CB cb(this);
825   scanReachableSymbols(beg, end, cb);
826   return cb;
827 }
828 
829 /// \class ScanReachableSymbols
830 /// A Utility class that allows to visit the reachable symbols using a custom
831 /// SymbolVisitor.
832 class ScanReachableSymbols {
833   typedef llvm::DenseSet<const void*> VisitedItems;
834 
835   VisitedItems visited;
836   ProgramStateRef state;
837   SymbolVisitor &visitor;
838 public:
839 
ScanReachableSymbols(ProgramStateRef st,SymbolVisitor & v)840   ScanReachableSymbols(ProgramStateRef st, SymbolVisitor& v)
841     : state(st), visitor(v) {}
842 
843   bool scan(nonloc::LazyCompoundVal val);
844   bool scan(nonloc::CompoundVal val);
845   bool scan(SVal val);
846   bool scan(const MemRegion *R);
847   bool scan(const SymExpr *sym);
848 };
849 
850 } // end ento namespace
851 
852 } // end clang namespace
853 
854 #endif
855