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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_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 #include <utility>
30 
31 namespace llvm {
32 class APSInt;
33 }
34 
35 namespace clang {
36 class ASTContext;
37 
38 namespace ento {
39 
40 class CallEvent;
41 class CallEventManager;
42 
43 typedef std::unique_ptr<ConstraintManager>(*ConstraintManagerCreator)(
44     ProgramStateManager &, SubEngine *);
45 typedef std::unique_ptr<StoreManager>(*StoreManagerCreator)(
46     ProgramStateManager &);
47 
48 //===----------------------------------------------------------------------===//
49 // ProgramStateTrait - Traits used by the Generic Data Map of a ProgramState.
50 //===----------------------------------------------------------------------===//
51 
52 template <typename T> struct ProgramStatePartialTrait;
53 
54 template <typename T> struct ProgramStateTrait {
55   typedef typename T::data_type data_type;
MakeVoidPtrProgramStateTrait56   static inline void *MakeVoidPtr(data_type D) { return (void*) D; }
MakeDataProgramStateTrait57   static inline data_type MakeData(void *const* P) {
58     return P ? (data_type) *P : (data_type) 0;
59   }
60 };
61 
62 /// \class ProgramState
63 /// ProgramState - This class encapsulates:
64 ///
65 ///    1. A mapping from expressions to values (Environment)
66 ///    2. A mapping from locations to values (Store)
67 ///    3. Constraints on symbolic values (GenericDataMap)
68 ///
69 ///  Together these represent the "abstract state" of a program.
70 ///
71 ///  ProgramState is intended to be used as a functional object; that is,
72 ///  once it is created and made "persistent" in a FoldingSet, its
73 ///  values will never change.
74 class ProgramState : public llvm::FoldingSetNode {
75 public:
76   typedef llvm::ImmutableSet<llvm::APSInt*>                IntSetTy;
77   typedef llvm::ImmutableMap<void*, void*>                 GenericDataMap;
78 
79 private:
80   void operator=(const ProgramState& R) = delete;
81 
82   friend class ProgramStateManager;
83   friend class ExplodedGraph;
84   friend class ExplodedNode;
85 
86   ProgramStateManager *stateMgr;
87   Environment Env;           // Maps a Stmt to its current SVal.
88   Store store;               // Maps a location to its current value.
89   GenericDataMap   GDM;      // Custom data stored by a client of this class.
90   unsigned refCount;
91 
92   /// makeWithStore - Return a ProgramState with the same values as the current
93   ///  state with the exception of using the specified Store.
94   ProgramStateRef makeWithStore(const StoreRef &store) const;
95 
96   void setStore(const StoreRef &storeRef);
97 
98 public:
99   /// This ctor is used when creating the first ProgramState object.
100   ProgramState(ProgramStateManager *mgr, const Environment& env,
101           StoreRef st, GenericDataMap gdm);
102 
103   /// Copy ctor - We must explicitly define this or else the "Next" ptr
104   ///  in FoldingSetNode will also get copied.
105   ProgramState(const ProgramState &RHS);
106 
107   ~ProgramState();
108 
109   /// Return the ProgramStateManager associated with this state.
getStateManager()110   ProgramStateManager &getStateManager() const {
111     return *stateMgr;
112   }
113 
114   /// Return the ConstraintManager.
115   ConstraintManager &getConstraintManager() const;
116 
117   /// getEnvironment - Return the environment associated with this state.
118   ///  The environment is the mapping from expressions to values.
getEnvironment()119   const Environment& getEnvironment() const { return Env; }
120 
121   /// Return the store associated with this state.  The store
122   ///  is a mapping from locations to values.
getStore()123   Store getStore() const { return store; }
124 
125 
126   /// getGDM - Return the generic data map associated with this state.
getGDM()127   GenericDataMap getGDM() const { return GDM; }
128 
setGDM(GenericDataMap gdm)129   void setGDM(GenericDataMap gdm) { GDM = gdm; }
130 
131   /// Profile - Profile the contents of a ProgramState object for use in a
132   ///  FoldingSet.  Two ProgramState objects are considered equal if they
133   ///  have the same Environment, Store, and GenericDataMap.
Profile(llvm::FoldingSetNodeID & ID,const ProgramState * V)134   static void Profile(llvm::FoldingSetNodeID& ID, const ProgramState *V) {
135     V->Env.Profile(ID);
136     ID.AddPointer(V->store);
137     V->GDM.Profile(ID);
138   }
139 
140   /// Profile - Used to profile the contents of this object for inclusion
141   ///  in a FoldingSet.
Profile(llvm::FoldingSetNodeID & ID)142   void Profile(llvm::FoldingSetNodeID& ID) const {
143     Profile(ID, this);
144   }
145 
146   BasicValueFactory &getBasicVals() const;
147   SymbolManager &getSymbolManager() const;
148 
149   //==---------------------------------------------------------------------==//
150   // Constraints on values.
151   //==---------------------------------------------------------------------==//
152   //
153   // Each ProgramState records constraints on symbolic values.  These constraints
154   // are managed using the ConstraintManager associated with a ProgramStateManager.
155   // As constraints gradually accrue on symbolic values, added constraints
156   // may conflict and indicate that a state is infeasible (as no real values
157   // could satisfy all the constraints).  This is the principal mechanism
158   // for modeling path-sensitivity in ExprEngine/ProgramState.
159   //
160   // Various "assume" methods form the interface for adding constraints to
161   // symbolic values.  A call to 'assume' indicates an assumption being placed
162   // on one or symbolic values.  'assume' methods take the following inputs:
163   //
164   //  (1) A ProgramState object representing the current state.
165   //
166   //  (2) The assumed constraint (which is specific to a given "assume" method).
167   //
168   //  (3) A binary value "Assumption" that indicates whether the constraint is
169   //      assumed to be true or false.
170   //
171   // The output of "assume*" is a new ProgramState object with the added constraints.
172   // If no new state is feasible, NULL is returned.
173   //
174 
175   /// Assumes that the value of \p cond is zero (if \p assumption is "false")
176   /// or non-zero (if \p assumption is "true").
177   ///
178   /// This returns a new state with the added constraint on \p cond.
179   /// If no new state is feasible, NULL is returned.
180   ProgramStateRef assume(DefinedOrUnknownSVal cond, bool assumption) const;
181 
182   /// Assumes both "true" and "false" for \p cond, and returns both
183   /// corresponding states (respectively).
184   ///
185   /// This is more efficient than calling assume() twice. Note that one (but not
186   /// both) of the returned states may be NULL.
187   std::pair<ProgramStateRef, ProgramStateRef>
188   assume(DefinedOrUnknownSVal cond) const;
189 
190   ProgramStateRef assumeInBound(DefinedOrUnknownSVal idx,
191                                DefinedOrUnknownSVal upperBound,
192                                bool assumption,
193                                QualType IndexType = QualType()) const;
194 
195   /// Assumes that the value of \p Val is bounded with [\p From; \p To]
196   /// (if \p assumption is "true") or it is fully out of this range
197   /// (if \p assumption is "false").
198   ///
199   /// This returns a new state with the added constraint on \p cond.
200   /// If no new state is feasible, NULL is returned.
201   ProgramStateRef assumeWithinInclusiveRange(DefinedOrUnknownSVal Val,
202                                              const llvm::APSInt &From,
203                                              const llvm::APSInt &To,
204                                              bool assumption) const;
205 
206   /// Assumes given range both "true" and "false" for \p Val, and returns both
207   /// corresponding states (respectively).
208   ///
209   /// This is more efficient than calling assume() twice. Note that one (but not
210   /// both) of the returned states may be NULL.
211   std::pair<ProgramStateRef, ProgramStateRef>
212   assumeWithinInclusiveRange(DefinedOrUnknownSVal Val, const llvm::APSInt &From,
213                              const llvm::APSInt &To) const;
214 
215 
216   /// \brief Check if the given SVal is constrained to zero or is a zero
217   ///        constant.
218   ConditionTruthVal isNull(SVal V) const;
219 
220   /// Utility method for getting regions.
221   const VarRegion* getRegion(const VarDecl *D, const LocationContext *LC) const;
222 
223   //==---------------------------------------------------------------------==//
224   // Binding and retrieving values to/from the environment and symbolic store.
225   //==---------------------------------------------------------------------==//
226 
227   /// Create a new state by binding the value 'V' to the statement 'S' in the
228   /// state's environment.
229   ProgramStateRef BindExpr(const Stmt *S, const LocationContext *LCtx,
230                                SVal V, bool Invalidate = true) const;
231 
232   ProgramStateRef bindLoc(Loc location,
233                           SVal V,
234                           bool notifyChanges = true) const;
235 
236   ProgramStateRef bindLoc(SVal location, SVal V) const;
237 
238   ProgramStateRef bindDefault(SVal loc, SVal V) const;
239 
240   ProgramStateRef killBinding(Loc LV) const;
241 
242   /// \brief Returns the state with bindings for the given regions
243   ///  cleared from the store.
244   ///
245   /// Optionally invalidates global regions as well.
246   ///
247   /// \param Regions the set of regions to be invalidated.
248   /// \param E the expression that caused the invalidation.
249   /// \param BlockCount The number of times the current basic block has been
250   //         visited.
251   /// \param CausesPointerEscape the flag is set to true when
252   ///        the invalidation entails escape of a symbol (representing a
253   ///        pointer). For example, due to it being passed as an argument in a
254   ///        call.
255   /// \param IS the set of invalidated symbols.
256   /// \param Call if non-null, the invalidated regions represent parameters to
257   ///        the call and should be considered directly invalidated.
258   /// \param ITraits information about special handling for a particular
259   ///        region/symbol.
260   ProgramStateRef
261   invalidateRegions(ArrayRef<const MemRegion *> Regions, const Expr *E,
262                     unsigned BlockCount, const LocationContext *LCtx,
263                     bool CausesPointerEscape, InvalidatedSymbols *IS = nullptr,
264                     const CallEvent *Call = nullptr,
265                     RegionAndSymbolInvalidationTraits *ITraits = nullptr) const;
266 
267   ProgramStateRef
268   invalidateRegions(ArrayRef<SVal> Regions, const Expr *E,
269                     unsigned BlockCount, const LocationContext *LCtx,
270                     bool CausesPointerEscape, InvalidatedSymbols *IS = nullptr,
271                     const CallEvent *Call = nullptr,
272                     RegionAndSymbolInvalidationTraits *ITraits = nullptr) const;
273 
274   /// enterStackFrame - Returns the state for entry to the given stack frame,
275   ///  preserving the current state.
276   ProgramStateRef enterStackFrame(const CallEvent &Call,
277                                   const StackFrameContext *CalleeCtx) const;
278 
279   /// Get the lvalue for a variable reference.
280   Loc getLValue(const VarDecl *D, const LocationContext *LC) const;
281 
282   Loc getLValue(const CompoundLiteralExpr *literal,
283                 const LocationContext *LC) const;
284 
285   /// Get the lvalue for an ivar reference.
286   SVal getLValue(const ObjCIvarDecl *decl, SVal base) const;
287 
288   /// Get the lvalue for a field reference.
289   SVal getLValue(const FieldDecl *decl, SVal Base) const;
290 
291   /// Get the lvalue for an indirect field reference.
292   SVal getLValue(const IndirectFieldDecl *decl, SVal Base) const;
293 
294   /// Get the lvalue for an array index.
295   SVal getLValue(QualType ElementType, SVal Idx, SVal Base) const;
296 
297   /// Returns the SVal bound to the statement 'S' in the state's environment.
298   SVal getSVal(const Stmt *S, const LocationContext *LCtx) const;
299 
300   SVal getSValAsScalarOrLoc(const Stmt *Ex, const LocationContext *LCtx) const;
301 
302   /// \brief Return the value bound to the specified location.
303   /// Returns UnknownVal() if none found.
304   SVal getSVal(Loc LV, QualType T = QualType()) const;
305 
306   /// Returns the "raw" SVal bound to LV before any value simplfication.
307   SVal getRawSVal(Loc LV, QualType T= QualType()) const;
308 
309   /// \brief Return the value bound to the specified location.
310   /// Returns UnknownVal() if none found.
311   SVal getSVal(const MemRegion* R) const;
312 
313   SVal getSValAsScalarOrLoc(const MemRegion *R) const;
314 
315   /// \brief Visits the symbols reachable from the given SVal using the provided
316   /// SymbolVisitor.
317   ///
318   /// This is a convenience API. Consider using ScanReachableSymbols class
319   /// directly when making multiple scans on the same state with the same
320   /// visitor to avoid repeated initialization cost.
321   /// \sa ScanReachableSymbols
322   bool scanReachableSymbols(SVal val, SymbolVisitor& visitor) const;
323 
324   /// \brief Visits the symbols reachable from the SVals in the given range
325   /// using the provided SymbolVisitor.
326   bool scanReachableSymbols(const SVal *I, const SVal *E,
327                             SymbolVisitor &visitor) const;
328 
329   /// \brief Visits the symbols reachable from the regions in the given
330   /// MemRegions range using the provided SymbolVisitor.
331   bool scanReachableSymbols(const MemRegion * const *I,
332                             const MemRegion * const *E,
333                             SymbolVisitor &visitor) const;
334 
335   template <typename CB> CB scanReachableSymbols(SVal val) const;
336   template <typename CB> CB scanReachableSymbols(const SVal *beg,
337                                                  const SVal *end) const;
338 
339   template <typename CB> CB
340   scanReachableSymbols(const MemRegion * const *beg,
341                        const MemRegion * const *end) const;
342 
343   /// Create a new state in which the statement is marked as tainted.
344   ProgramStateRef addTaint(const Stmt *S, const LocationContext *LCtx,
345                                TaintTagType Kind = TaintTagGeneric) const;
346 
347   /// Create a new state in which the symbol is marked as tainted.
348   ProgramStateRef addTaint(SymbolRef S,
349                                TaintTagType Kind = TaintTagGeneric) const;
350 
351   /// Create a new state in which the region symbol is marked as tainted.
352   ProgramStateRef addTaint(const MemRegion *R,
353                                TaintTagType Kind = TaintTagGeneric) const;
354 
355   /// Check if the statement is tainted in the current state.
356   bool isTainted(const Stmt *S, const LocationContext *LCtx,
357                  TaintTagType Kind = TaintTagGeneric) const;
358   bool isTainted(SVal V, TaintTagType Kind = TaintTagGeneric) const;
359   bool isTainted(SymbolRef Sym, TaintTagType Kind = TaintTagGeneric) const;
360   bool isTainted(const MemRegion *Reg, TaintTagType Kind=TaintTagGeneric) const;
361 
362   //==---------------------------------------------------------------------==//
363   // Accessing the Generic Data Map (GDM).
364   //==---------------------------------------------------------------------==//
365 
366   void *const* FindGDM(void *K) const;
367 
368   template<typename T>
369   ProgramStateRef add(typename ProgramStateTrait<T>::key_type K) const;
370 
371   template <typename T>
372   typename ProgramStateTrait<T>::data_type
get()373   get() const {
374     return ProgramStateTrait<T>::MakeData(FindGDM(ProgramStateTrait<T>::GDMIndex()));
375   }
376 
377   template<typename T>
378   typename ProgramStateTrait<T>::lookup_type
get(typename ProgramStateTrait<T>::key_type key)379   get(typename ProgramStateTrait<T>::key_type key) const {
380     void *const* d = FindGDM(ProgramStateTrait<T>::GDMIndex());
381     return ProgramStateTrait<T>::Lookup(ProgramStateTrait<T>::MakeData(d), key);
382   }
383 
384   template <typename T>
385   typename ProgramStateTrait<T>::context_type get_context() const;
386 
387 
388   template<typename T>
389   ProgramStateRef remove(typename ProgramStateTrait<T>::key_type K) const;
390 
391   template<typename T>
392   ProgramStateRef remove(typename ProgramStateTrait<T>::key_type K,
393                         typename ProgramStateTrait<T>::context_type C) const;
394   template <typename T>
395   ProgramStateRef remove() const;
396 
397   template<typename T>
398   ProgramStateRef set(typename ProgramStateTrait<T>::data_type D) const;
399 
400   template<typename T>
401   ProgramStateRef set(typename ProgramStateTrait<T>::key_type K,
402                      typename ProgramStateTrait<T>::value_type E) const;
403 
404   template<typename T>
405   ProgramStateRef set(typename ProgramStateTrait<T>::key_type K,
406                      typename ProgramStateTrait<T>::value_type E,
407                      typename ProgramStateTrait<T>::context_type C) const;
408 
409   template<typename T>
contains(typename ProgramStateTrait<T>::key_type key)410   bool contains(typename ProgramStateTrait<T>::key_type key) const {
411     void *const* d = FindGDM(ProgramStateTrait<T>::GDMIndex());
412     return ProgramStateTrait<T>::Contains(ProgramStateTrait<T>::MakeData(d), key);
413   }
414 
415   // Pretty-printing.
416   void print(raw_ostream &Out, const char *nl = "\n",
417              const char *sep = "") const;
418   void printDOT(raw_ostream &Out) const;
419   void printTaint(raw_ostream &Out, const char *nl = "\n",
420                   const char *sep = "") const;
421 
422   void dump() const;
423   void dumpTaint() const;
424 
425 private:
426   friend void ProgramStateRetain(const ProgramState *state);
427   friend void ProgramStateRelease(const ProgramState *state);
428 
429   /// \sa invalidateValues()
430   /// \sa invalidateRegions()
431   ProgramStateRef
432   invalidateRegionsImpl(ArrayRef<SVal> Values,
433                         const Expr *E, unsigned BlockCount,
434                         const LocationContext *LCtx,
435                         bool ResultsInSymbolEscape,
436                         InvalidatedSymbols *IS,
437                         RegionAndSymbolInvalidationTraits *HTraits,
438                         const CallEvent *Call) const;
439 };
440 
441 //===----------------------------------------------------------------------===//
442 // ProgramStateManager - Factory object for ProgramStates.
443 //===----------------------------------------------------------------------===//
444 
445 class ProgramStateManager {
446   friend class ProgramState;
447   friend void ProgramStateRelease(const ProgramState *state);
448 private:
449   /// Eng - The SubEngine that owns this state manager.
450   SubEngine *Eng; /* Can be null. */
451 
452   EnvironmentManager                   EnvMgr;
453   std::unique_ptr<StoreManager>        StoreMgr;
454   std::unique_ptr<ConstraintManager>   ConstraintMgr;
455 
456   ProgramState::GenericDataMap::Factory     GDMFactory;
457 
458   typedef llvm::DenseMap<void*,std::pair<void*,void (*)(void*)> > GDMContextsTy;
459   GDMContextsTy GDMContexts;
460 
461   /// StateSet - FoldingSet containing all the states created for analyzing
462   ///  a particular function.  This is used to unique states.
463   llvm::FoldingSet<ProgramState> StateSet;
464 
465   /// Object that manages the data for all created SVals.
466   std::unique_ptr<SValBuilder> svalBuilder;
467 
468   /// Manages memory for created CallEvents.
469   std::unique_ptr<CallEventManager> CallEventMgr;
470 
471   /// A BumpPtrAllocator to allocate states.
472   llvm::BumpPtrAllocator &Alloc;
473 
474   /// A vector of ProgramStates that we can reuse.
475   std::vector<ProgramState *> freeStates;
476 
477 public:
478   ProgramStateManager(ASTContext &Ctx,
479                  StoreManagerCreator CreateStoreManager,
480                  ConstraintManagerCreator CreateConstraintManager,
481                  llvm::BumpPtrAllocator& alloc,
482                  SubEngine *subeng);
483 
484   ~ProgramStateManager();
485 
486   ProgramStateRef getInitialState(const LocationContext *InitLoc);
487 
getContext()488   ASTContext &getContext() { return svalBuilder->getContext(); }
getContext()489   const ASTContext &getContext() const { return svalBuilder->getContext(); }
490 
getBasicVals()491   BasicValueFactory &getBasicVals() {
492     return svalBuilder->getBasicValueFactory();
493   }
494 
getSValBuilder()495   SValBuilder &getSValBuilder() {
496     return *svalBuilder;
497   }
498 
getSymbolManager()499   SymbolManager &getSymbolManager() {
500     return svalBuilder->getSymbolManager();
501   }
getSymbolManager()502   const SymbolManager &getSymbolManager() const {
503     return svalBuilder->getSymbolManager();
504   }
505 
getAllocator()506   llvm::BumpPtrAllocator& getAllocator() { return Alloc; }
507 
getRegionManager()508   MemRegionManager& getRegionManager() {
509     return svalBuilder->getRegionManager();
510   }
getRegionManager()511   const MemRegionManager& getRegionManager() const {
512     return svalBuilder->getRegionManager();
513   }
514 
getCallEventManager()515   CallEventManager &getCallEventManager() { return *CallEventMgr; }
516 
getStoreManager()517   StoreManager& getStoreManager() { return *StoreMgr; }
getConstraintManager()518   ConstraintManager& getConstraintManager() { return *ConstraintMgr; }
getOwningEngine()519   SubEngine* getOwningEngine() { return Eng; }
520 
521   ProgramStateRef removeDeadBindings(ProgramStateRef St,
522                                     const StackFrameContext *LCtx,
523                                     SymbolReaper& SymReaper);
524 
525 public:
526 
ArrayToPointer(Loc Array,QualType ElementTy)527   SVal ArrayToPointer(Loc Array, QualType ElementTy) {
528     return StoreMgr->ArrayToPointer(Array, ElementTy);
529   }
530 
531   // Methods that manipulate the GDM.
532   ProgramStateRef addGDM(ProgramStateRef St, void *Key, void *Data);
533   ProgramStateRef removeGDM(ProgramStateRef state, void *Key);
534 
535   // Methods that query & manipulate the Store.
536 
iterBindings(ProgramStateRef state,StoreManager::BindingsHandler & F)537   void iterBindings(ProgramStateRef state, StoreManager::BindingsHandler& F) {
538     StoreMgr->iterBindings(state->getStore(), F);
539   }
540 
541   ProgramStateRef getPersistentState(ProgramState &Impl);
542   ProgramStateRef getPersistentStateWithGDM(ProgramStateRef FromState,
543                                            ProgramStateRef GDMState);
544 
haveEqualEnvironments(ProgramStateRef S1,ProgramStateRef S2)545   bool haveEqualEnvironments(ProgramStateRef S1, ProgramStateRef S2) {
546     return S1->Env == S2->Env;
547   }
548 
haveEqualStores(ProgramStateRef S1,ProgramStateRef S2)549   bool haveEqualStores(ProgramStateRef S1, ProgramStateRef S2) {
550     return S1->store == S2->store;
551   }
552 
553   //==---------------------------------------------------------------------==//
554   // Generic Data Map methods.
555   //==---------------------------------------------------------------------==//
556   //
557   // ProgramStateManager and ProgramState support a "generic data map" that allows
558   // different clients of ProgramState objects to embed arbitrary data within a
559   // ProgramState object.  The generic data map is essentially an immutable map
560   // from a "tag" (that acts as the "key" for a client) and opaque values.
561   // Tags/keys and values are simply void* values.  The typical way that clients
562   // generate unique tags are by taking the address of a static variable.
563   // Clients are responsible for ensuring that data values referred to by a
564   // the data pointer are immutable (and thus are essentially purely functional
565   // data).
566   //
567   // The templated methods below use the ProgramStateTrait<T> class
568   // to resolve keys into the GDM and to return data values to clients.
569   //
570 
571   // Trait based GDM dispatch.
572   template <typename T>
set(ProgramStateRef st,typename ProgramStateTrait<T>::data_type D)573   ProgramStateRef set(ProgramStateRef st, typename ProgramStateTrait<T>::data_type D) {
574     return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
575                   ProgramStateTrait<T>::MakeVoidPtr(D));
576   }
577 
578   template<typename T>
set(ProgramStateRef st,typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::value_type V,typename ProgramStateTrait<T>::context_type C)579   ProgramStateRef set(ProgramStateRef st,
580                      typename ProgramStateTrait<T>::key_type K,
581                      typename ProgramStateTrait<T>::value_type V,
582                      typename ProgramStateTrait<T>::context_type C) {
583 
584     return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
585      ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Set(st->get<T>(), K, V, C)));
586   }
587 
588   template <typename T>
add(ProgramStateRef st,typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::context_type C)589   ProgramStateRef add(ProgramStateRef st,
590                      typename ProgramStateTrait<T>::key_type K,
591                      typename ProgramStateTrait<T>::context_type C) {
592     return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
593         ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Add(st->get<T>(), K, C)));
594   }
595 
596   template <typename T>
remove(ProgramStateRef st,typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::context_type C)597   ProgramStateRef remove(ProgramStateRef st,
598                         typename ProgramStateTrait<T>::key_type K,
599                         typename ProgramStateTrait<T>::context_type C) {
600 
601     return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
602      ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Remove(st->get<T>(), K, C)));
603   }
604 
605   template <typename T>
remove(ProgramStateRef st)606   ProgramStateRef remove(ProgramStateRef st) {
607     return removeGDM(st, ProgramStateTrait<T>::GDMIndex());
608   }
609 
610   void *FindGDMContext(void *index,
611                        void *(*CreateContext)(llvm::BumpPtrAllocator&),
612                        void  (*DeleteContext)(void*));
613 
614   template <typename T>
get_context()615   typename ProgramStateTrait<T>::context_type get_context() {
616     void *p = FindGDMContext(ProgramStateTrait<T>::GDMIndex(),
617                              ProgramStateTrait<T>::CreateContext,
618                              ProgramStateTrait<T>::DeleteContext);
619 
620     return ProgramStateTrait<T>::MakeContext(p);
621   }
622 
EndPath(ProgramStateRef St)623   void EndPath(ProgramStateRef St) {
624     ConstraintMgr->EndPath(St);
625   }
626 };
627 
628 
629 //===----------------------------------------------------------------------===//
630 // Out-of-line method definitions for ProgramState.
631 //===----------------------------------------------------------------------===//
632 
getConstraintManager()633 inline ConstraintManager &ProgramState::getConstraintManager() const {
634   return stateMgr->getConstraintManager();
635 }
636 
getRegion(const VarDecl * D,const LocationContext * LC)637 inline const VarRegion* ProgramState::getRegion(const VarDecl *D,
638                                                 const LocationContext *LC) const
639 {
640   return getStateManager().getRegionManager().getVarRegion(D, LC);
641 }
642 
assume(DefinedOrUnknownSVal Cond,bool Assumption)643 inline ProgramStateRef ProgramState::assume(DefinedOrUnknownSVal Cond,
644                                       bool Assumption) const {
645   if (Cond.isUnknown())
646     return this;
647 
648   return getStateManager().ConstraintMgr
649       ->assume(this, Cond.castAs<DefinedSVal>(), Assumption);
650 }
651 
652 inline std::pair<ProgramStateRef , ProgramStateRef >
assume(DefinedOrUnknownSVal Cond)653 ProgramState::assume(DefinedOrUnknownSVal Cond) const {
654   if (Cond.isUnknown())
655     return std::make_pair(this, this);
656 
657   return getStateManager().ConstraintMgr
658       ->assumeDual(this, Cond.castAs<DefinedSVal>());
659 }
660 
661 inline ProgramStateRef
assumeWithinInclusiveRange(DefinedOrUnknownSVal Val,const llvm::APSInt & From,const llvm::APSInt & To,bool Assumption)662 ProgramState::assumeWithinInclusiveRange(DefinedOrUnknownSVal Val,
663                                          const llvm::APSInt &From,
664                                          const llvm::APSInt &To,
665                                          bool Assumption) const {
666   if (Val.isUnknown())
667     return this;
668 
669   assert(Val.getAs<NonLoc>() && "Only NonLocs are supported!");
670 
671   return getStateManager().ConstraintMgr->assumeWithinInclusiveRange(
672         this, Val.castAs<NonLoc>(), From, To, Assumption);
673 }
674 
675 inline std::pair<ProgramStateRef, ProgramStateRef>
assumeWithinInclusiveRange(DefinedOrUnknownSVal Val,const llvm::APSInt & From,const llvm::APSInt & To)676 ProgramState::assumeWithinInclusiveRange(DefinedOrUnknownSVal Val,
677                                          const llvm::APSInt &From,
678                                          const llvm::APSInt &To) const {
679   if (Val.isUnknown())
680     return std::make_pair(this, this);
681 
682   assert(Val.getAs<NonLoc>() && "Only NonLocs are supported!");
683 
684   return getStateManager().ConstraintMgr
685       ->assumeWithinInclusiveRangeDual(this, Val.castAs<NonLoc>(), From, To);
686 }
687 
bindLoc(SVal LV,SVal V)688 inline ProgramStateRef ProgramState::bindLoc(SVal LV, SVal V) const {
689   if (Optional<Loc> L = LV.getAs<Loc>())
690     return bindLoc(*L, V);
691   return this;
692 }
693 
getLValue(const VarDecl * VD,const LocationContext * LC)694 inline Loc ProgramState::getLValue(const VarDecl *VD,
695                                const LocationContext *LC) const {
696   return getStateManager().StoreMgr->getLValueVar(VD, LC);
697 }
698 
getLValue(const CompoundLiteralExpr * literal,const LocationContext * LC)699 inline Loc ProgramState::getLValue(const CompoundLiteralExpr *literal,
700                                const LocationContext *LC) const {
701   return getStateManager().StoreMgr->getLValueCompoundLiteral(literal, LC);
702 }
703 
getLValue(const ObjCIvarDecl * D,SVal Base)704 inline SVal ProgramState::getLValue(const ObjCIvarDecl *D, SVal Base) const {
705   return getStateManager().StoreMgr->getLValueIvar(D, Base);
706 }
707 
getLValue(const FieldDecl * D,SVal Base)708 inline SVal ProgramState::getLValue(const FieldDecl *D, SVal Base) const {
709   return getStateManager().StoreMgr->getLValueField(D, Base);
710 }
711 
getLValue(const IndirectFieldDecl * D,SVal Base)712 inline SVal ProgramState::getLValue(const IndirectFieldDecl *D,
713                                     SVal Base) const {
714   StoreManager &SM = *getStateManager().StoreMgr;
715   for (const auto *I : D->chain()) {
716     Base = SM.getLValueField(cast<FieldDecl>(I), Base);
717   }
718 
719   return Base;
720 }
721 
getLValue(QualType ElementType,SVal Idx,SVal Base)722 inline SVal ProgramState::getLValue(QualType ElementType, SVal Idx, SVal Base) const{
723   if (Optional<NonLoc> N = Idx.getAs<NonLoc>())
724     return getStateManager().StoreMgr->getLValueElement(ElementType, *N, Base);
725   return UnknownVal();
726 }
727 
getSVal(const Stmt * Ex,const LocationContext * LCtx)728 inline SVal ProgramState::getSVal(const Stmt *Ex,
729                                   const LocationContext *LCtx) const{
730   return Env.getSVal(EnvironmentEntry(Ex, LCtx),
731                      *getStateManager().svalBuilder);
732 }
733 
734 inline SVal
getSValAsScalarOrLoc(const Stmt * S,const LocationContext * LCtx)735 ProgramState::getSValAsScalarOrLoc(const Stmt *S,
736                                    const LocationContext *LCtx) const {
737   if (const Expr *Ex = dyn_cast<Expr>(S)) {
738     QualType T = Ex->getType();
739     if (Ex->isGLValue() || Loc::isLocType(T) ||
740         T->isIntegralOrEnumerationType())
741       return getSVal(S, LCtx);
742   }
743 
744   return UnknownVal();
745 }
746 
getRawSVal(Loc LV,QualType T)747 inline SVal ProgramState::getRawSVal(Loc LV, QualType T) const {
748   return getStateManager().StoreMgr->getBinding(getStore(), LV, T);
749 }
750 
getSVal(const MemRegion * R)751 inline SVal ProgramState::getSVal(const MemRegion* R) const {
752   return getStateManager().StoreMgr->getBinding(getStore(),
753                                                 loc::MemRegionVal(R));
754 }
755 
getBasicVals()756 inline BasicValueFactory &ProgramState::getBasicVals() const {
757   return getStateManager().getBasicVals();
758 }
759 
getSymbolManager()760 inline SymbolManager &ProgramState::getSymbolManager() const {
761   return getStateManager().getSymbolManager();
762 }
763 
764 template<typename T>
add(typename ProgramStateTrait<T>::key_type K)765 ProgramStateRef ProgramState::add(typename ProgramStateTrait<T>::key_type K) const {
766   return getStateManager().add<T>(this, K, get_context<T>());
767 }
768 
769 template <typename T>
get_context()770 typename ProgramStateTrait<T>::context_type ProgramState::get_context() const {
771   return getStateManager().get_context<T>();
772 }
773 
774 template<typename T>
remove(typename ProgramStateTrait<T>::key_type K)775 ProgramStateRef ProgramState::remove(typename ProgramStateTrait<T>::key_type K) const {
776   return getStateManager().remove<T>(this, K, get_context<T>());
777 }
778 
779 template<typename T>
remove(typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::context_type C)780 ProgramStateRef ProgramState::remove(typename ProgramStateTrait<T>::key_type K,
781                                typename ProgramStateTrait<T>::context_type C) const {
782   return getStateManager().remove<T>(this, K, C);
783 }
784 
785 template <typename T>
remove()786 ProgramStateRef ProgramState::remove() const {
787   return getStateManager().remove<T>(this);
788 }
789 
790 template<typename T>
set(typename ProgramStateTrait<T>::data_type D)791 ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::data_type D) const {
792   return getStateManager().set<T>(this, D);
793 }
794 
795 template<typename T>
set(typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::value_type E)796 ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::key_type K,
797                             typename ProgramStateTrait<T>::value_type E) const {
798   return getStateManager().set<T>(this, K, E, get_context<T>());
799 }
800 
801 template<typename T>
set(typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::value_type E,typename ProgramStateTrait<T>::context_type C)802 ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::key_type K,
803                             typename ProgramStateTrait<T>::value_type E,
804                             typename ProgramStateTrait<T>::context_type C) const {
805   return getStateManager().set<T>(this, K, E, C);
806 }
807 
808 template <typename CB>
scanReachableSymbols(SVal val)809 CB ProgramState::scanReachableSymbols(SVal val) const {
810   CB cb(this);
811   scanReachableSymbols(val, cb);
812   return cb;
813 }
814 
815 template <typename CB>
scanReachableSymbols(const SVal * beg,const SVal * end)816 CB ProgramState::scanReachableSymbols(const SVal *beg, const SVal *end) const {
817   CB cb(this);
818   scanReachableSymbols(beg, end, cb);
819   return cb;
820 }
821 
822 template <typename CB>
scanReachableSymbols(const MemRegion * const * beg,const MemRegion * const * end)823 CB ProgramState::scanReachableSymbols(const MemRegion * const *beg,
824                                  const MemRegion * const *end) const {
825   CB cb(this);
826   scanReachableSymbols(beg, end, cb);
827   return cb;
828 }
829 
830 /// \class ScanReachableSymbols
831 /// A Utility class that allows to visit the reachable symbols using a custom
832 /// SymbolVisitor.
833 class ScanReachableSymbols {
834   typedef llvm::DenseSet<const void*> VisitedItems;
835 
836   VisitedItems visited;
837   ProgramStateRef state;
838   SymbolVisitor &visitor;
839 public:
ScanReachableSymbols(ProgramStateRef st,SymbolVisitor & v)840   ScanReachableSymbols(ProgramStateRef st, SymbolVisitor &v)
841       : state(std::move(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