1 //== ProgramState.h - Path-sensitive "State" for tracking values -*- C++ -*--=//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file defines the state of the program along the analysisa path.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #ifndef LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_PROGRAMSTATE_H
14 #define LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_PROGRAMSTATE_H
15
16 #include "clang/Basic/LLVM.h"
17 #include "clang/StaticAnalyzer/Core/PathSensitive/ConstraintManager.h"
18 #include "clang/StaticAnalyzer/Core/PathSensitive/DynamicTypeInfo.h"
19 #include "clang/StaticAnalyzer/Core/PathSensitive/Environment.h"
20 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState_Fwd.h"
21 #include "clang/StaticAnalyzer/Core/PathSensitive/SValBuilder.h"
22 #include "clang/StaticAnalyzer/Core/PathSensitive/Store.h"
23 #include "llvm/ADT/FoldingSet.h"
24 #include "llvm/ADT/ImmutableMap.h"
25 #include "llvm/Support/Allocator.h"
26 #include <optional>
27 #include <utility>
28
29 namespace llvm {
30 class APSInt;
31 }
32
33 namespace clang {
34 class ASTContext;
35
36 namespace ento {
37
38 class AnalysisManager;
39 class CallEvent;
40 class CallEventManager;
41
42 typedef std::unique_ptr<ConstraintManager>(*ConstraintManagerCreator)(
43 ProgramStateManager &, ExprEngine *);
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 ProgramStateTrait {
52 typedef typename T::data_type data_type;
MakeVoidPtrProgramStateTrait53 static inline void *MakeVoidPtr(data_type D) { return (void*) D; }
MakeDataProgramStateTrait54 static inline data_type MakeData(void *const* P) {
55 return P ? (data_type) *P : (data_type) 0;
56 }
57 };
58
59 /// \class ProgramState
60 /// ProgramState - This class encapsulates:
61 ///
62 /// 1. A mapping from expressions to values (Environment)
63 /// 2. A mapping from locations to values (Store)
64 /// 3. Constraints on symbolic values (GenericDataMap)
65 ///
66 /// Together these represent the "abstract state" of a program.
67 ///
68 /// ProgramState is intended to be used as a functional object; that is,
69 /// once it is created and made "persistent" in a FoldingSet, its
70 /// values will never change.
71 class ProgramState : public llvm::FoldingSetNode {
72 public:
73 typedef llvm::ImmutableSet<llvm::APSInt*> IntSetTy;
74 typedef llvm::ImmutableMap<void*, void*> GenericDataMap;
75
76 private:
77 void operator=(const ProgramState& R) = delete;
78
79 friend class ProgramStateManager;
80 friend class ExplodedGraph;
81 friend class ExplodedNode;
82 friend class NodeBuilder;
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
89 // A state is infeasible if there is a contradiction among the constraints.
90 // An infeasible state is represented by a `nullptr`.
91 // In the sense of `assumeDual`, a state can have two children by adding a
92 // new constraint and the negation of that new constraint. A parent state is
93 // over-constrained if both of its children are infeasible. In the
94 // mathematical sense, it means that the parent is infeasible and we should
95 // have realized that at the moment when we have created it. However, we
96 // could not recognize that because of the imperfection of the underlying
97 // constraint solver. We say it is posteriorly over-constrained because we
98 // recognize that a parent is infeasible only *after* a new and more specific
99 // constraint and its negation are evaluated.
100 //
101 // Example:
102 //
103 // x * x = 4 and x is in the range [0, 1]
104 // This is an already infeasible state, but the constraint solver is not
105 // capable of handling sqrt, thus we don't know it yet.
106 //
107 // Then a new constraint `x = 0` is added. At this moment the constraint
108 // solver re-evaluates the existing constraints and realizes the
109 // contradiction `0 * 0 = 4`.
110 // We also evaluate the negated constraint `x != 0`; the constraint solver
111 // deduces `x = 1` and then realizes the contradiction `1 * 1 = 4`.
112 // Both children are infeasible, thus the parent state is marked as
113 // posteriorly over-constrained. These parents are handled with special care:
114 // we do not allow transitions to exploded nodes with such states.
115 bool PosteriorlyOverconstrained = false;
116 // Make internal constraint solver entities friends so they can access the
117 // overconstrained-related functions. We want to keep this API inaccessible
118 // for Checkers.
119 friend class ConstraintManager;
isPosteriorlyOverconstrained()120 bool isPosteriorlyOverconstrained() const {
121 return PosteriorlyOverconstrained;
122 }
123 ProgramStateRef cloneAsPosteriorlyOverconstrained() const;
124
125 unsigned refCount;
126
127 /// makeWithStore - Return a ProgramState with the same values as the current
128 /// state with the exception of using the specified Store.
129 ProgramStateRef makeWithStore(const StoreRef &store) const;
130
131 void setStore(const StoreRef &storeRef);
132
133 public:
134 /// This ctor is used when creating the first ProgramState object.
135 ProgramState(ProgramStateManager *mgr, const Environment& env,
136 StoreRef st, GenericDataMap gdm);
137
138 /// Copy ctor - We must explicitly define this or else the "Next" ptr
139 /// in FoldingSetNode will also get copied.
140 ProgramState(const ProgramState &RHS);
141
142 ~ProgramState();
143
144 int64_t getID() const;
145
146 /// Return the ProgramStateManager associated with this state.
getStateManager()147 ProgramStateManager &getStateManager() const {
148 return *stateMgr;
149 }
150
151 AnalysisManager &getAnalysisManager() const;
152
153 /// Return the ConstraintManager.
154 ConstraintManager &getConstraintManager() const;
155
156 /// getEnvironment - Return the environment associated with this state.
157 /// The environment is the mapping from expressions to values.
getEnvironment()158 const Environment& getEnvironment() const { return Env; }
159
160 /// Return the store associated with this state. The store
161 /// is a mapping from locations to values.
getStore()162 Store getStore() const { return store; }
163
164
165 /// getGDM - Return the generic data map associated with this state.
getGDM()166 GenericDataMap getGDM() const { return GDM; }
167
setGDM(GenericDataMap gdm)168 void setGDM(GenericDataMap gdm) { GDM = gdm; }
169
170 /// Profile - Profile the contents of a ProgramState object for use in a
171 /// FoldingSet. Two ProgramState objects are considered equal if they
172 /// have the same Environment, Store, and GenericDataMap.
Profile(llvm::FoldingSetNodeID & ID,const ProgramState * V)173 static void Profile(llvm::FoldingSetNodeID& ID, const ProgramState *V) {
174 V->Env.Profile(ID);
175 ID.AddPointer(V->store);
176 V->GDM.Profile(ID);
177 ID.AddBoolean(V->PosteriorlyOverconstrained);
178 }
179
180 /// Profile - Used to profile the contents of this object for inclusion
181 /// in a FoldingSet.
Profile(llvm::FoldingSetNodeID & ID)182 void Profile(llvm::FoldingSetNodeID& ID) const {
183 Profile(ID, this);
184 }
185
186 BasicValueFactory &getBasicVals() const;
187 SymbolManager &getSymbolManager() const;
188
189 //==---------------------------------------------------------------------==//
190 // Constraints on values.
191 //==---------------------------------------------------------------------==//
192 //
193 // Each ProgramState records constraints on symbolic values. These constraints
194 // are managed using the ConstraintManager associated with a ProgramStateManager.
195 // As constraints gradually accrue on symbolic values, added constraints
196 // may conflict and indicate that a state is infeasible (as no real values
197 // could satisfy all the constraints). This is the principal mechanism
198 // for modeling path-sensitivity in ExprEngine/ProgramState.
199 //
200 // Various "assume" methods form the interface for adding constraints to
201 // symbolic values. A call to 'assume' indicates an assumption being placed
202 // on one or symbolic values. 'assume' methods take the following inputs:
203 //
204 // (1) A ProgramState object representing the current state.
205 //
206 // (2) The assumed constraint (which is specific to a given "assume" method).
207 //
208 // (3) A binary value "Assumption" that indicates whether the constraint is
209 // assumed to be true or false.
210 //
211 // The output of "assume*" is a new ProgramState object with the added constraints.
212 // If no new state is feasible, NULL is returned.
213 //
214
215 /// Assumes that the value of \p cond is zero (if \p assumption is "false")
216 /// or non-zero (if \p assumption is "true").
217 ///
218 /// This returns a new state with the added constraint on \p cond.
219 /// If no new state is feasible, NULL is returned.
220 [[nodiscard]] ProgramStateRef assume(DefinedOrUnknownSVal cond,
221 bool assumption) const;
222
223 /// Assumes both "true" and "false" for \p cond, and returns both
224 /// corresponding states (respectively).
225 ///
226 /// This is more efficient than calling assume() twice. Note that one (but not
227 /// both) of the returned states may be NULL.
228 [[nodiscard]] std::pair<ProgramStateRef, ProgramStateRef>
229 assume(DefinedOrUnknownSVal cond) const;
230
231 [[nodiscard]] std::pair<ProgramStateRef, ProgramStateRef>
232 assumeInBoundDual(DefinedOrUnknownSVal idx, DefinedOrUnknownSVal upperBound,
233 QualType IndexType = QualType()) const;
234
235 [[nodiscard]] ProgramStateRef
236 assumeInBound(DefinedOrUnknownSVal idx, DefinedOrUnknownSVal upperBound,
237 bool assumption, QualType IndexType = QualType()) const;
238
239 /// Assumes that the value of \p Val is bounded with [\p From; \p To]
240 /// (if \p assumption is "true") or it is fully out of this range
241 /// (if \p assumption is "false").
242 ///
243 /// This returns a new state with the added constraint on \p cond.
244 /// If no new state is feasible, NULL is returned.
245 [[nodiscard]] ProgramStateRef assumeInclusiveRange(DefinedOrUnknownSVal Val,
246 const llvm::APSInt &From,
247 const llvm::APSInt &To,
248 bool assumption) const;
249
250 /// Assumes given range both "true" and "false" for \p Val, and returns both
251 /// corresponding states (respectively).
252 ///
253 /// This is more efficient than calling assume() twice. Note that one (but not
254 /// both) of the returned states may be NULL.
255 [[nodiscard]] std::pair<ProgramStateRef, ProgramStateRef>
256 assumeInclusiveRange(DefinedOrUnknownSVal Val, const llvm::APSInt &From,
257 const llvm::APSInt &To) const;
258
259 /// Check if the given SVal is not constrained to zero and is not
260 /// a zero constant.
261 ConditionTruthVal isNonNull(SVal V) const;
262
263 /// Check if the given SVal is constrained to zero or is a zero
264 /// constant.
265 ConditionTruthVal isNull(SVal V) const;
266
267 /// \return Whether values \p Lhs and \p Rhs are equal.
268 ConditionTruthVal areEqual(SVal Lhs, SVal Rhs) const;
269
270 /// Utility method for getting regions.
271 LLVM_ATTRIBUTE_RETURNS_NONNULL
272 const VarRegion* getRegion(const VarDecl *D, const LocationContext *LC) const;
273
274 //==---------------------------------------------------------------------==//
275 // Binding and retrieving values to/from the environment and symbolic store.
276 //==---------------------------------------------------------------------==//
277
278 /// Create a new state by binding the value 'V' to the statement 'S' in the
279 /// state's environment.
280 [[nodiscard]] ProgramStateRef BindExpr(const Stmt *S,
281 const LocationContext *LCtx, SVal V,
282 bool Invalidate = true) const;
283
284 [[nodiscard]] ProgramStateRef bindLoc(Loc location, SVal V,
285 const LocationContext *LCtx,
286 bool notifyChanges = true) const;
287
288 [[nodiscard]] ProgramStateRef bindLoc(SVal location, SVal V,
289 const LocationContext *LCtx) const;
290
291 /// Initializes the region of memory represented by \p loc with an initial
292 /// value. Once initialized, all values loaded from any sub-regions of that
293 /// region will be equal to \p V, unless overwritten later by the program.
294 /// This method should not be used on regions that are already initialized.
295 /// If you need to indicate that memory contents have suddenly become unknown
296 /// within a certain region of memory, consider invalidateRegions().
297 [[nodiscard]] ProgramStateRef
298 bindDefaultInitial(SVal loc, SVal V, const LocationContext *LCtx) const;
299
300 /// Performs C++ zero-initialization procedure on the region of memory
301 /// represented by \p loc.
302 [[nodiscard]] ProgramStateRef
303 bindDefaultZero(SVal loc, const LocationContext *LCtx) const;
304
305 [[nodiscard]] ProgramStateRef killBinding(Loc LV) const;
306
307 /// Returns the state with bindings for the given regions
308 /// cleared from the store.
309 ///
310 /// Optionally invalidates global regions as well.
311 ///
312 /// \param Regions the set of regions to be invalidated.
313 /// \param E the expression that caused the invalidation.
314 /// \param BlockCount The number of times the current basic block has been
315 // visited.
316 /// \param CausesPointerEscape the flag is set to true when
317 /// the invalidation entails escape of a symbol (representing a
318 /// pointer). For example, due to it being passed as an argument in a
319 /// call.
320 /// \param IS the set of invalidated symbols.
321 /// \param Call if non-null, the invalidated regions represent parameters to
322 /// the call and should be considered directly invalidated.
323 /// \param ITraits information about special handling for a particular
324 /// region/symbol.
325 [[nodiscard]] ProgramStateRef
326 invalidateRegions(ArrayRef<const MemRegion *> Regions, const Expr *E,
327 unsigned BlockCount, const LocationContext *LCtx,
328 bool CausesPointerEscape, InvalidatedSymbols *IS = nullptr,
329 const CallEvent *Call = nullptr,
330 RegionAndSymbolInvalidationTraits *ITraits = nullptr) const;
331
332 [[nodiscard]] ProgramStateRef
333 invalidateRegions(ArrayRef<SVal> Regions, const Expr *E, unsigned BlockCount,
334 const LocationContext *LCtx, bool CausesPointerEscape,
335 InvalidatedSymbols *IS = nullptr,
336 const CallEvent *Call = nullptr,
337 RegionAndSymbolInvalidationTraits *ITraits = nullptr) const;
338
339 /// enterStackFrame - Returns the state for entry to the given stack frame,
340 /// preserving the current state.
341 [[nodiscard]] ProgramStateRef
342 enterStackFrame(const CallEvent &Call,
343 const StackFrameContext *CalleeCtx) const;
344
345 /// Return the value of 'self' if available in the given context.
346 SVal getSelfSVal(const LocationContext *LC) const;
347
348 /// Get the lvalue for a base class object reference.
349 Loc getLValue(const CXXBaseSpecifier &BaseSpec, const SubRegion *Super) const;
350
351 /// Get the lvalue for a base class object reference.
352 Loc getLValue(const CXXRecordDecl *BaseClass, const SubRegion *Super,
353 bool IsVirtual) const;
354
355 /// Get the lvalue for a variable reference.
356 Loc getLValue(const VarDecl *D, const LocationContext *LC) const;
357
358 Loc getLValue(const CompoundLiteralExpr *literal,
359 const LocationContext *LC) const;
360
361 /// Get the lvalue for an ivar reference.
362 SVal getLValue(const ObjCIvarDecl *decl, SVal base) const;
363
364 /// Get the lvalue for a field reference.
365 SVal getLValue(const FieldDecl *decl, SVal Base) const;
366
367 /// Get the lvalue for an indirect field reference.
368 SVal getLValue(const IndirectFieldDecl *decl, SVal Base) const;
369
370 /// Get the lvalue for an array index.
371 SVal getLValue(QualType ElementType, SVal Idx, SVal Base) const;
372
373 /// Returns the SVal bound to the statement 'S' in the state's environment.
374 SVal getSVal(const Stmt *S, const LocationContext *LCtx) const;
375
376 SVal getSValAsScalarOrLoc(const Stmt *Ex, const LocationContext *LCtx) const;
377
378 /// Return the value bound to the specified location.
379 /// Returns UnknownVal() if none found.
380 SVal getSVal(Loc LV, QualType T = QualType()) const;
381
382 /// Returns the "raw" SVal bound to LV before any value simplfication.
383 SVal getRawSVal(Loc LV, QualType T= QualType()) const;
384
385 /// Return the value bound to the specified location.
386 /// Returns UnknownVal() if none found.
387 SVal getSVal(const MemRegion* R, QualType T = QualType()) const;
388
389 /// Return the value bound to the specified location, assuming
390 /// that the value is a scalar integer or an enumeration or a pointer.
391 /// Returns UnknownVal() if none found or the region is not known to hold
392 /// a value of such type.
393 SVal getSValAsScalarOrLoc(const MemRegion *R) const;
394
395 using region_iterator = const MemRegion **;
396
397 /// Visits the symbols reachable from the given SVal using the provided
398 /// SymbolVisitor.
399 ///
400 /// This is a convenience API. Consider using ScanReachableSymbols class
401 /// directly when making multiple scans on the same state with the same
402 /// visitor to avoid repeated initialization cost.
403 /// \sa ScanReachableSymbols
404 bool scanReachableSymbols(SVal val, SymbolVisitor& visitor) const;
405
406 /// Visits the symbols reachable from the regions in the given
407 /// MemRegions range using the provided SymbolVisitor.
408 bool scanReachableSymbols(llvm::iterator_range<region_iterator> Reachable,
409 SymbolVisitor &visitor) const;
410
411 template <typename CB> CB scanReachableSymbols(SVal val) const;
412 template <typename CB> CB
413 scanReachableSymbols(llvm::iterator_range<region_iterator> Reachable) const;
414
415 //==---------------------------------------------------------------------==//
416 // Accessing the Generic Data Map (GDM).
417 //==---------------------------------------------------------------------==//
418
419 void *const* FindGDM(void *K) const;
420
421 template <typename T>
422 [[nodiscard]] ProgramStateRef
423 add(typename ProgramStateTrait<T>::key_type K) const;
424
425 template <typename T>
426 typename ProgramStateTrait<T>::data_type
get()427 get() const {
428 return ProgramStateTrait<T>::MakeData(FindGDM(ProgramStateTrait<T>::GDMIndex()));
429 }
430
431 template<typename T>
432 typename ProgramStateTrait<T>::lookup_type
get(typename ProgramStateTrait<T>::key_type key)433 get(typename ProgramStateTrait<T>::key_type key) const {
434 void *const* d = FindGDM(ProgramStateTrait<T>::GDMIndex());
435 return ProgramStateTrait<T>::Lookup(ProgramStateTrait<T>::MakeData(d), key);
436 }
437
438 template <typename T>
439 typename ProgramStateTrait<T>::context_type get_context() const;
440
441 template <typename T>
442 [[nodiscard]] ProgramStateRef
443 remove(typename ProgramStateTrait<T>::key_type K) const;
444
445 template <typename T>
446 [[nodiscard]] ProgramStateRef
447 remove(typename ProgramStateTrait<T>::key_type K,
448 typename ProgramStateTrait<T>::context_type C) const;
449
450 template <typename T> [[nodiscard]] ProgramStateRef remove() const;
451
452 template <typename T>
453 [[nodiscard]] ProgramStateRef
454 set(typename ProgramStateTrait<T>::data_type D) const;
455
456 template <typename T>
457 [[nodiscard]] ProgramStateRef
458 set(typename ProgramStateTrait<T>::key_type K,
459 typename ProgramStateTrait<T>::value_type E) const;
460
461 template <typename T>
462 [[nodiscard]] ProgramStateRef
463 set(typename ProgramStateTrait<T>::key_type K,
464 typename ProgramStateTrait<T>::value_type E,
465 typename ProgramStateTrait<T>::context_type C) const;
466
467 template<typename T>
contains(typename ProgramStateTrait<T>::key_type key)468 bool contains(typename ProgramStateTrait<T>::key_type key) const {
469 void *const* d = FindGDM(ProgramStateTrait<T>::GDMIndex());
470 return ProgramStateTrait<T>::Contains(ProgramStateTrait<T>::MakeData(d), key);
471 }
472
473 // Pretty-printing.
474 void printJson(raw_ostream &Out, const LocationContext *LCtx = nullptr,
475 const char *NL = "\n", unsigned int Space = 0,
476 bool IsDot = false) const;
477
478 void printDOT(raw_ostream &Out, const LocationContext *LCtx = nullptr,
479 unsigned int Space = 0) const;
480
481 void dump() const;
482
483 private:
484 friend void ProgramStateRetain(const ProgramState *state);
485 friend void ProgramStateRelease(const ProgramState *state);
486
487 /// \sa invalidateValues()
488 /// \sa invalidateRegions()
489 ProgramStateRef
490 invalidateRegionsImpl(ArrayRef<SVal> Values,
491 const Expr *E, unsigned BlockCount,
492 const LocationContext *LCtx,
493 bool ResultsInSymbolEscape,
494 InvalidatedSymbols *IS,
495 RegionAndSymbolInvalidationTraits *HTraits,
496 const CallEvent *Call) const;
497
498 SVal wrapSymbolicRegion(SVal Base) const;
499 };
500
501 //===----------------------------------------------------------------------===//
502 // ProgramStateManager - Factory object for ProgramStates.
503 //===----------------------------------------------------------------------===//
504
505 class ProgramStateManager {
506 friend class ProgramState;
507 friend void ProgramStateRelease(const ProgramState *state);
508 private:
509 /// Eng - The ExprEngine that owns this state manager.
510 ExprEngine *Eng; /* Can be null. */
511
512 EnvironmentManager EnvMgr;
513 std::unique_ptr<StoreManager> StoreMgr;
514 std::unique_ptr<ConstraintManager> ConstraintMgr;
515
516 ProgramState::GenericDataMap::Factory GDMFactory;
517
518 typedef llvm::DenseMap<void*,std::pair<void*,void (*)(void*)> > GDMContextsTy;
519 GDMContextsTy GDMContexts;
520
521 /// StateSet - FoldingSet containing all the states created for analyzing
522 /// a particular function. This is used to unique states.
523 llvm::FoldingSet<ProgramState> StateSet;
524
525 /// Object that manages the data for all created SVals.
526 std::unique_ptr<SValBuilder> svalBuilder;
527
528 /// Manages memory for created CallEvents.
529 std::unique_ptr<CallEventManager> CallEventMgr;
530
531 /// A BumpPtrAllocator to allocate states.
532 llvm::BumpPtrAllocator &Alloc;
533
534 /// A vector of ProgramStates that we can reuse.
535 std::vector<ProgramState *> freeStates;
536
537 public:
538 ProgramStateManager(ASTContext &Ctx,
539 StoreManagerCreator CreateStoreManager,
540 ConstraintManagerCreator CreateConstraintManager,
541 llvm::BumpPtrAllocator& alloc,
542 ExprEngine *expreng);
543
544 ~ProgramStateManager();
545
546 ProgramStateRef getInitialState(const LocationContext *InitLoc);
547
getContext()548 ASTContext &getContext() { return svalBuilder->getContext(); }
getContext()549 const ASTContext &getContext() const { return svalBuilder->getContext(); }
550
getBasicVals()551 BasicValueFactory &getBasicVals() {
552 return svalBuilder->getBasicValueFactory();
553 }
554
getSValBuilder()555 SValBuilder &getSValBuilder() {
556 return *svalBuilder;
557 }
558
getSValBuilder()559 const SValBuilder &getSValBuilder() const {
560 return *svalBuilder;
561 }
562
getSymbolManager()563 SymbolManager &getSymbolManager() {
564 return svalBuilder->getSymbolManager();
565 }
getSymbolManager()566 const SymbolManager &getSymbolManager() const {
567 return svalBuilder->getSymbolManager();
568 }
569
getAllocator()570 llvm::BumpPtrAllocator& getAllocator() { return Alloc; }
571
getRegionManager()572 MemRegionManager& getRegionManager() {
573 return svalBuilder->getRegionManager();
574 }
getRegionManager()575 const MemRegionManager &getRegionManager() const {
576 return svalBuilder->getRegionManager();
577 }
578
getCallEventManager()579 CallEventManager &getCallEventManager() { return *CallEventMgr; }
580
getStoreManager()581 StoreManager &getStoreManager() { return *StoreMgr; }
getConstraintManager()582 ConstraintManager &getConstraintManager() { return *ConstraintMgr; }
getOwningEngine()583 ExprEngine &getOwningEngine() { return *Eng; }
584
585 ProgramStateRef
586 removeDeadBindingsFromEnvironmentAndStore(ProgramStateRef St,
587 const StackFrameContext *LCtx,
588 SymbolReaper &SymReaper);
589
590 public:
591
ArrayToPointer(Loc Array,QualType ElementTy)592 SVal ArrayToPointer(Loc Array, QualType ElementTy) {
593 return StoreMgr->ArrayToPointer(Array, ElementTy);
594 }
595
596 // Methods that manipulate the GDM.
597 ProgramStateRef addGDM(ProgramStateRef St, void *Key, void *Data);
598 ProgramStateRef removeGDM(ProgramStateRef state, void *Key);
599
600 // Methods that query & manipulate the Store.
601
iterBindings(ProgramStateRef state,StoreManager::BindingsHandler & F)602 void iterBindings(ProgramStateRef state, StoreManager::BindingsHandler& F) {
603 StoreMgr->iterBindings(state->getStore(), F);
604 }
605
606 ProgramStateRef getPersistentState(ProgramState &Impl);
607 ProgramStateRef getPersistentStateWithGDM(ProgramStateRef FromState,
608 ProgramStateRef GDMState);
609
haveEqualConstraints(ProgramStateRef S1,ProgramStateRef S2)610 bool haveEqualConstraints(ProgramStateRef S1, ProgramStateRef S2) const {
611 return ConstraintMgr->haveEqualConstraints(S1, S2);
612 }
613
haveEqualEnvironments(ProgramStateRef S1,ProgramStateRef S2)614 bool haveEqualEnvironments(ProgramStateRef S1, ProgramStateRef S2) const {
615 return S1->Env == S2->Env;
616 }
617
haveEqualStores(ProgramStateRef S1,ProgramStateRef S2)618 bool haveEqualStores(ProgramStateRef S1, ProgramStateRef S2) const {
619 return S1->store == S2->store;
620 }
621
622 //==---------------------------------------------------------------------==//
623 // Generic Data Map methods.
624 //==---------------------------------------------------------------------==//
625 //
626 // ProgramStateManager and ProgramState support a "generic data map" that allows
627 // different clients of ProgramState objects to embed arbitrary data within a
628 // ProgramState object. The generic data map is essentially an immutable map
629 // from a "tag" (that acts as the "key" for a client) and opaque values.
630 // Tags/keys and values are simply void* values. The typical way that clients
631 // generate unique tags are by taking the address of a static variable.
632 // Clients are responsible for ensuring that data values referred to by a
633 // the data pointer are immutable (and thus are essentially purely functional
634 // data).
635 //
636 // The templated methods below use the ProgramStateTrait<T> class
637 // to resolve keys into the GDM and to return data values to clients.
638 //
639
640 // Trait based GDM dispatch.
641 template <typename T>
set(ProgramStateRef st,typename ProgramStateTrait<T>::data_type D)642 ProgramStateRef set(ProgramStateRef st, typename ProgramStateTrait<T>::data_type D) {
643 return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
644 ProgramStateTrait<T>::MakeVoidPtr(D));
645 }
646
647 template<typename T>
set(ProgramStateRef st,typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::value_type V,typename ProgramStateTrait<T>::context_type C)648 ProgramStateRef set(ProgramStateRef st,
649 typename ProgramStateTrait<T>::key_type K,
650 typename ProgramStateTrait<T>::value_type V,
651 typename ProgramStateTrait<T>::context_type C) {
652
653 return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
654 ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Set(st->get<T>(), K, V, C)));
655 }
656
657 template <typename T>
add(ProgramStateRef st,typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::context_type C)658 ProgramStateRef add(ProgramStateRef st,
659 typename ProgramStateTrait<T>::key_type K,
660 typename ProgramStateTrait<T>::context_type C) {
661 return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
662 ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Add(st->get<T>(), K, C)));
663 }
664
665 template <typename T>
remove(ProgramStateRef st,typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::context_type C)666 ProgramStateRef remove(ProgramStateRef st,
667 typename ProgramStateTrait<T>::key_type K,
668 typename ProgramStateTrait<T>::context_type C) {
669
670 return addGDM(st, ProgramStateTrait<T>::GDMIndex(),
671 ProgramStateTrait<T>::MakeVoidPtr(ProgramStateTrait<T>::Remove(st->get<T>(), K, C)));
672 }
673
674 template <typename T>
remove(ProgramStateRef st)675 ProgramStateRef remove(ProgramStateRef st) {
676 return removeGDM(st, ProgramStateTrait<T>::GDMIndex());
677 }
678
679 void *FindGDMContext(void *index,
680 void *(*CreateContext)(llvm::BumpPtrAllocator&),
681 void (*DeleteContext)(void*));
682
683 template <typename T>
get_context()684 typename ProgramStateTrait<T>::context_type get_context() {
685 void *p = FindGDMContext(ProgramStateTrait<T>::GDMIndex(),
686 ProgramStateTrait<T>::CreateContext,
687 ProgramStateTrait<T>::DeleteContext);
688
689 return ProgramStateTrait<T>::MakeContext(p);
690 }
691 };
692
693
694 //===----------------------------------------------------------------------===//
695 // Out-of-line method definitions for ProgramState.
696 //===----------------------------------------------------------------------===//
697
getConstraintManager()698 inline ConstraintManager &ProgramState::getConstraintManager() const {
699 return stateMgr->getConstraintManager();
700 }
701
getRegion(const VarDecl * D,const LocationContext * LC)702 inline const VarRegion* ProgramState::getRegion(const VarDecl *D,
703 const LocationContext *LC) const
704 {
705 return getStateManager().getRegionManager().getVarRegion(D, LC);
706 }
707
assume(DefinedOrUnknownSVal Cond,bool Assumption)708 inline ProgramStateRef ProgramState::assume(DefinedOrUnknownSVal Cond,
709 bool Assumption) const {
710 if (Cond.isUnknown())
711 return this;
712
713 return getStateManager().ConstraintMgr
714 ->assume(this, Cond.castAs<DefinedSVal>(), Assumption);
715 }
716
717 inline std::pair<ProgramStateRef , ProgramStateRef >
assume(DefinedOrUnknownSVal Cond)718 ProgramState::assume(DefinedOrUnknownSVal Cond) const {
719 if (Cond.isUnknown())
720 return std::make_pair(this, this);
721
722 return getStateManager().ConstraintMgr
723 ->assumeDual(this, Cond.castAs<DefinedSVal>());
724 }
725
assumeInclusiveRange(DefinedOrUnknownSVal Val,const llvm::APSInt & From,const llvm::APSInt & To,bool Assumption)726 inline ProgramStateRef ProgramState::assumeInclusiveRange(
727 DefinedOrUnknownSVal Val, const llvm::APSInt &From, const llvm::APSInt &To,
728 bool Assumption) const {
729 if (Val.isUnknown())
730 return this;
731
732 assert(isa<NonLoc>(Val) && "Only NonLocs are supported!");
733
734 return getStateManager().ConstraintMgr->assumeInclusiveRange(
735 this, Val.castAs<NonLoc>(), From, To, Assumption);
736 }
737
738 inline std::pair<ProgramStateRef, ProgramStateRef>
assumeInclusiveRange(DefinedOrUnknownSVal Val,const llvm::APSInt & From,const llvm::APSInt & To)739 ProgramState::assumeInclusiveRange(DefinedOrUnknownSVal Val,
740 const llvm::APSInt &From,
741 const llvm::APSInt &To) const {
742 if (Val.isUnknown())
743 return std::make_pair(this, this);
744
745 assert(isa<NonLoc>(Val) && "Only NonLocs are supported!");
746
747 return getStateManager().ConstraintMgr->assumeInclusiveRangeDual(
748 this, Val.castAs<NonLoc>(), From, To);
749 }
750
bindLoc(SVal LV,SVal V,const LocationContext * LCtx)751 inline ProgramStateRef ProgramState::bindLoc(SVal LV, SVal V, const LocationContext *LCtx) const {
752 if (std::optional<Loc> L = LV.getAs<Loc>())
753 return bindLoc(*L, V, LCtx);
754 return this;
755 }
756
getLValue(const CXXBaseSpecifier & BaseSpec,const SubRegion * Super)757 inline Loc ProgramState::getLValue(const CXXBaseSpecifier &BaseSpec,
758 const SubRegion *Super) const {
759 const auto *Base = BaseSpec.getType()->getAsCXXRecordDecl();
760 return loc::MemRegionVal(
761 getStateManager().getRegionManager().getCXXBaseObjectRegion(
762 Base, Super, BaseSpec.isVirtual()));
763 }
764
getLValue(const CXXRecordDecl * BaseClass,const SubRegion * Super,bool IsVirtual)765 inline Loc ProgramState::getLValue(const CXXRecordDecl *BaseClass,
766 const SubRegion *Super,
767 bool IsVirtual) const {
768 return loc::MemRegionVal(
769 getStateManager().getRegionManager().getCXXBaseObjectRegion(
770 BaseClass, Super, IsVirtual));
771 }
772
getLValue(const VarDecl * VD,const LocationContext * LC)773 inline Loc ProgramState::getLValue(const VarDecl *VD,
774 const LocationContext *LC) const {
775 return getStateManager().StoreMgr->getLValueVar(VD, LC);
776 }
777
getLValue(const CompoundLiteralExpr * literal,const LocationContext * LC)778 inline Loc ProgramState::getLValue(const CompoundLiteralExpr *literal,
779 const LocationContext *LC) const {
780 return getStateManager().StoreMgr->getLValueCompoundLiteral(literal, LC);
781 }
782
getLValue(const ObjCIvarDecl * D,SVal Base)783 inline SVal ProgramState::getLValue(const ObjCIvarDecl *D, SVal Base) const {
784 return getStateManager().StoreMgr->getLValueIvar(D, Base);
785 }
786
getLValue(QualType ElementType,SVal Idx,SVal Base)787 inline SVal ProgramState::getLValue(QualType ElementType, SVal Idx, SVal Base) const{
788 if (std::optional<NonLoc> N = Idx.getAs<NonLoc>())
789 return getStateManager().StoreMgr->getLValueElement(ElementType, *N, Base);
790 return UnknownVal();
791 }
792
getSVal(const Stmt * Ex,const LocationContext * LCtx)793 inline SVal ProgramState::getSVal(const Stmt *Ex,
794 const LocationContext *LCtx) const{
795 return Env.getSVal(EnvironmentEntry(Ex, LCtx),
796 *getStateManager().svalBuilder);
797 }
798
799 inline SVal
getSValAsScalarOrLoc(const Stmt * S,const LocationContext * LCtx)800 ProgramState::getSValAsScalarOrLoc(const Stmt *S,
801 const LocationContext *LCtx) const {
802 if (const Expr *Ex = dyn_cast<Expr>(S)) {
803 QualType T = Ex->getType();
804 if (Ex->isGLValue() || Loc::isLocType(T) ||
805 T->isIntegralOrEnumerationType())
806 return getSVal(S, LCtx);
807 }
808
809 return UnknownVal();
810 }
811
getRawSVal(Loc LV,QualType T)812 inline SVal ProgramState::getRawSVal(Loc LV, QualType T) const {
813 return getStateManager().StoreMgr->getBinding(getStore(), LV, T);
814 }
815
getSVal(const MemRegion * R,QualType T)816 inline SVal ProgramState::getSVal(const MemRegion* R, QualType T) const {
817 return getStateManager().StoreMgr->getBinding(getStore(),
818 loc::MemRegionVal(R),
819 T);
820 }
821
getBasicVals()822 inline BasicValueFactory &ProgramState::getBasicVals() const {
823 return getStateManager().getBasicVals();
824 }
825
getSymbolManager()826 inline SymbolManager &ProgramState::getSymbolManager() const {
827 return getStateManager().getSymbolManager();
828 }
829
830 template<typename T>
add(typename ProgramStateTrait<T>::key_type K)831 ProgramStateRef ProgramState::add(typename ProgramStateTrait<T>::key_type K) const {
832 return getStateManager().add<T>(this, K, get_context<T>());
833 }
834
835 template <typename T>
get_context()836 typename ProgramStateTrait<T>::context_type ProgramState::get_context() const {
837 return getStateManager().get_context<T>();
838 }
839
840 template<typename T>
remove(typename ProgramStateTrait<T>::key_type K)841 ProgramStateRef ProgramState::remove(typename ProgramStateTrait<T>::key_type K) const {
842 return getStateManager().remove<T>(this, K, get_context<T>());
843 }
844
845 template<typename T>
remove(typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::context_type C)846 ProgramStateRef ProgramState::remove(typename ProgramStateTrait<T>::key_type K,
847 typename ProgramStateTrait<T>::context_type C) const {
848 return getStateManager().remove<T>(this, K, C);
849 }
850
851 template <typename T>
remove()852 ProgramStateRef ProgramState::remove() const {
853 return getStateManager().remove<T>(this);
854 }
855
856 template<typename T>
set(typename ProgramStateTrait<T>::data_type D)857 ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::data_type D) const {
858 return getStateManager().set<T>(this, D);
859 }
860
861 template<typename T>
set(typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::value_type E)862 ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::key_type K,
863 typename ProgramStateTrait<T>::value_type E) const {
864 return getStateManager().set<T>(this, K, E, get_context<T>());
865 }
866
867 template<typename T>
set(typename ProgramStateTrait<T>::key_type K,typename ProgramStateTrait<T>::value_type E,typename ProgramStateTrait<T>::context_type C)868 ProgramStateRef ProgramState::set(typename ProgramStateTrait<T>::key_type K,
869 typename ProgramStateTrait<T>::value_type E,
870 typename ProgramStateTrait<T>::context_type C) const {
871 return getStateManager().set<T>(this, K, E, C);
872 }
873
874 template <typename CB>
scanReachableSymbols(SVal val)875 CB ProgramState::scanReachableSymbols(SVal val) const {
876 CB cb(this);
877 scanReachableSymbols(val, cb);
878 return cb;
879 }
880
881 template <typename CB>
scanReachableSymbols(llvm::iterator_range<region_iterator> Reachable)882 CB ProgramState::scanReachableSymbols(
883 llvm::iterator_range<region_iterator> Reachable) const {
884 CB cb(this);
885 scanReachableSymbols(Reachable, cb);
886 return cb;
887 }
888
889 /// \class ScanReachableSymbols
890 /// A utility class that visits the reachable symbols using a custom
891 /// SymbolVisitor. Terminates recursive traversal when the visitor function
892 /// returns false.
893 class ScanReachableSymbols {
894 typedef llvm::DenseSet<const void*> VisitedItems;
895
896 VisitedItems visited;
897 ProgramStateRef state;
898 SymbolVisitor &visitor;
899 public:
ScanReachableSymbols(ProgramStateRef st,SymbolVisitor & v)900 ScanReachableSymbols(ProgramStateRef st, SymbolVisitor &v)
901 : state(std::move(st)), visitor(v) {}
902
903 bool scan(nonloc::LazyCompoundVal val);
904 bool scan(nonloc::CompoundVal val);
905 bool scan(SVal val);
906 bool scan(const MemRegion *R);
907 bool scan(const SymExpr *sym);
908 };
909
910 } // end ento namespace
911
912 } // end clang namespace
913
914 #endif
915