1 //===- CallEvent.h - Wrapper for all function and method calls --*- C++ -*-===//
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
7 //===----------------------------------------------------------------------===//
9 /// \file This file defines CallEvent and its subclasses, which represent path-
10 /// sensitive instances of different kinds of function and method calls
11 /// (C, C++, and Objective-C).
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_CALLEVENT_H
16 #define LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_CALLEVENT_H
18 #include "clang/AST/Decl.h"
19 #include "clang/AST/DeclBase.h"
20 #include "clang/AST/DeclCXX.h"
21 #include "clang/AST/DeclObjC.h"
22 #include "clang/AST/Expr.h"
23 #include "clang/AST/ExprCXX.h"
24 #include "clang/AST/ExprObjC.h"
25 #include "clang/AST/Stmt.h"
26 #include "clang/AST/Type.h"
27 #include "clang/Basic/IdentifierTable.h"
28 #include "clang/Basic/LLVM.h"
29 #include "clang/Basic/SourceLocation.h"
30 #include "clang/Basic/SourceManager.h"
31 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
32 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
33 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState_Fwd.h"
34 #include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
35 #include "llvm/ADT/ArrayRef.h"
36 #include "llvm/ADT/IntrusiveRefCntPtr.h"
37 #include "llvm/ADT/PointerIntPair.h"
38 #include "llvm/ADT/PointerUnion.h"
39 #include "llvm/ADT/STLExtras.h"
40 #include "llvm/ADT/SmallVector.h"
41 #include "llvm/ADT/StringRef.h"
42 #include "llvm/Support/Allocator.h"
43 #include "llvm/Support/Casting.h"
44 #include "llvm/Support/ErrorHandling.h"
51 class LocationContext;
53 class ProgramPointTag;
54 class StackFrameContext;
63 CE_BEG_CXX_INSTANCE_CALLS = CE_CXXMember,
64 CE_END_CXX_INSTANCE_CALLS = CE_CXXDestructor,
67 CE_BEG_FUNCTION_CALLS = CE_Function,
68 CE_END_FUNCTION_CALLS = CE_CXXAllocator,
74 class CallDescription;
76 template<typename T = CallEvent>
77 class CallEventRef : public IntrusiveRefCntPtr<const T> {
79 CallEventRef(const T *Call) : IntrusiveRefCntPtr<const T>(Call) {}
80 CallEventRef(const CallEventRef &Orig) : IntrusiveRefCntPtr<const T>(Orig) {}
82 CallEventRef<T> cloneWithState(ProgramStateRef State) const {
83 return this->get()->template cloneWithState<T>(State);
86 // Allow implicit conversions to a superclass type, since CallEventRef
87 // behaves like a pointer-to-const.
88 template <typename SuperT>
89 operator CallEventRef<SuperT> () const {
94 /// \class RuntimeDefinition
95 /// Defines the runtime definition of the called function.
97 /// Encapsulates the information we have about which Decl will be used
98 /// when the call is executed on the given path. When dealing with dynamic
99 /// dispatch, the information is based on DynamicTypeInfo and might not be
101 class RuntimeDefinition {
102 /// The Declaration of the function which could be called at runtime.
103 /// NULL if not available.
104 const Decl *D = nullptr;
106 /// The region representing an object (ObjC/C++) on which the method is
107 /// called. With dynamic dispatch, the method definition depends on the
108 /// runtime type of this object. NULL when the DynamicTypeInfo is
110 const MemRegion *R = nullptr;
113 RuntimeDefinition() = default;
114 RuntimeDefinition(const Decl *InD): D(InD) {}
115 RuntimeDefinition(const Decl *InD, const MemRegion *InR): D(InD), R(InR) {}
117 const Decl *getDecl() { return D; }
119 /// Check if the definition we have is precise.
120 /// If not, it is possible that the call dispatches to another definition at
122 bool mayHaveOtherDefinitions() { return R != nullptr; }
124 /// When other definitions are possible, returns the region whose runtime type
125 /// determines the method definition.
126 const MemRegion *getDispatchRegion() { return R; }
129 /// Represents an abstract call to a function or method along a
132 /// CallEvents are created through the factory methods of CallEventManager.
134 /// CallEvents should always be cheap to create and destroy. In order for
135 /// CallEventManager to be able to re-use CallEvent-sized memory blocks,
136 /// subclasses of CallEvent may not add any data members to the base class.
137 /// Use the "Data" and "Location" fields instead.
140 using Kind = CallEventKind;
143 ProgramStateRef State;
144 const LocationContext *LCtx;
145 llvm::PointerUnion<const Expr *, const Decl *> Origin;
148 // This is user data for subclasses.
151 // This is user data for subclasses.
152 // This should come right before RefCount, so that the two fields can be
153 // packed together on LP64 platforms.
154 SourceLocation Location;
157 template <typename T> friend struct llvm::IntrusiveRefCntPtrInfo;
159 mutable unsigned RefCount = 0;
161 void Retain() const { ++RefCount; }
162 void Release() const;
165 friend class CallEventManager;
167 CallEvent(const Expr *E, ProgramStateRef state, const LocationContext *lctx)
168 : State(std::move(state)), LCtx(lctx), Origin(E) {}
170 CallEvent(const Decl *D, ProgramStateRef state, const LocationContext *lctx)
171 : State(std::move(state)), LCtx(lctx), Origin(D) {}
173 // DO NOT MAKE PUBLIC
174 CallEvent(const CallEvent &Original)
175 : State(Original.State), LCtx(Original.LCtx), Origin(Original.Origin),
176 Data(Original.Data), Location(Original.Location) {}
178 /// Copies this CallEvent, with vtable intact, into a new block of memory.
179 virtual void cloneTo(void *Dest) const = 0;
181 /// Get the value of arbitrary expressions at this point in the path.
182 SVal getSVal(const Stmt *S) const {
183 return getState()->getSVal(S, getLocationContext());
186 using ValueList = SmallVectorImpl<SVal>;
188 /// Used to specify non-argument regions that will be invalidated as a
189 /// result of this call.
190 virtual void getExtraInvalidatedValues(ValueList &Values,
191 RegionAndSymbolInvalidationTraits *ETraits) const {}
194 CallEvent &operator=(const CallEvent &) = delete;
195 virtual ~CallEvent() = default;
197 /// Returns the kind of call this is.
198 virtual Kind getKind() const = 0;
200 /// Returns the declaration of the function or method that will be
201 /// called. May be null.
202 virtual const Decl *getDecl() const {
203 return Origin.dyn_cast<const Decl *>();
206 /// The state in which the call is being evaluated.
207 const ProgramStateRef &getState() const {
211 /// The context in which the call is being evaluated.
212 const LocationContext *getLocationContext() const {
216 /// Returns the definition of the function or method that will be
218 virtual RuntimeDefinition getRuntimeDefinition() const = 0;
220 /// Returns the expression whose value will be the result of this call.
222 const Expr *getOriginExpr() const {
223 return Origin.dyn_cast<const Expr *>();
226 /// Returns the number of arguments (explicit and implicit).
228 /// Note that this may be greater than the number of parameters in the
229 /// callee's declaration, and that it may include arguments not written in
231 virtual unsigned getNumArgs() const = 0;
233 /// Returns true if the callee is known to be from a system header.
234 bool isInSystemHeader() const {
235 const Decl *D = getDecl();
239 SourceLocation Loc = D->getLocation();
241 const SourceManager &SM =
242 getState()->getStateManager().getContext().getSourceManager();
243 return SM.isInSystemHeader(D->getLocation());
246 // Special case for implicitly-declared global operator new/delete.
247 // These should be considered system functions.
248 if (const auto *FD = dyn_cast<FunctionDecl>(D))
249 return FD->isOverloadedOperator() && FD->isImplicit() && FD->isGlobal();
254 /// Returns true if the CallEvent is a call to a function that matches
255 /// the CallDescription.
257 /// Note that this function is not intended to be used to match Obj-C method
259 bool isCalled(const CallDescription &CD) const;
261 /// Returns a source range for the entire call, suitable for
262 /// outputting in diagnostics.
263 virtual SourceRange getSourceRange() const {
264 return getOriginExpr()->getSourceRange();
267 /// Returns the value of a given argument at the time of the call.
268 virtual SVal getArgSVal(unsigned Index) const;
270 /// Returns the expression associated with a given argument.
271 /// May be null if this expression does not appear in the source.
272 virtual const Expr *getArgExpr(unsigned Index) const { return nullptr; }
274 /// Returns the source range for errors associated with this argument.
276 /// May be invalid if the argument is not written in the source.
277 virtual SourceRange getArgSourceRange(unsigned Index) const;
279 /// Returns the result type, adjusted for references.
280 QualType getResultType() const;
282 /// Returns the return value of the call.
284 /// This should only be called if the CallEvent was created using a state in
285 /// which the return value has already been bound to the origin expression.
286 SVal getReturnValue() const;
288 /// Returns true if the type of any of the non-null arguments satisfies
290 bool hasNonNullArgumentsWithType(bool (*Condition)(QualType)) const;
292 /// Returns true if any of the arguments appear to represent callbacks.
293 bool hasNonZeroCallbackArg() const;
295 /// Returns true if any of the arguments is void*.
296 bool hasVoidPointerToNonConstArg() const;
298 /// Returns true if any of the arguments are known to escape to long-
299 /// term storage, even if this method will not modify them.
300 // NOTE: The exact semantics of this are still being defined!
301 // We don't really want a list of hardcoded exceptions in the long run,
302 // but we don't want duplicated lists of known APIs in the short term either.
303 virtual bool argumentsMayEscape() const {
304 return hasNonZeroCallbackArg();
307 /// Returns true if the callee is an externally-visible function in the
308 /// top-level namespace, such as \c malloc.
310 /// You can use this call to determine that a particular function really is
311 /// a library function and not, say, a C++ member function with the same name.
313 /// If a name is provided, the function must additionally match the given
316 /// Note that this deliberately excludes C++ library functions in the \c std
317 /// namespace, but will include C library functions accessed through the
318 /// \c std namespace. This also does not check if the function is declared
319 /// as 'extern "C"', or if it uses C++ name mangling.
320 // FIXME: Add a helper for checking namespaces.
321 // FIXME: Move this down to AnyFunctionCall once checkers have more
322 // precise callbacks.
323 bool isGlobalCFunction(StringRef SpecificName = StringRef()) const;
325 /// Returns the name of the callee, if its name is a simple identifier.
327 /// Note that this will fail for Objective-C methods, blocks, and C++
328 /// overloaded operators. The former is named by a Selector rather than a
329 /// simple identifier, and the latter two do not have names.
330 // FIXME: Move this down to AnyFunctionCall once checkers have more
331 // precise callbacks.
332 const IdentifierInfo *getCalleeIdentifier() const {
333 const auto *ND = dyn_cast_or_null<NamedDecl>(getDecl());
336 return ND->getIdentifier();
339 /// Returns an appropriate ProgramPoint for this call.
340 ProgramPoint getProgramPoint(bool IsPreVisit = false,
341 const ProgramPointTag *Tag = nullptr) const;
343 /// Returns a new state with all argument regions invalidated.
345 /// This accepts an alternate state in case some processing has already
347 ProgramStateRef invalidateRegions(unsigned BlockCount,
348 ProgramStateRef Orig = nullptr) const;
350 using FrameBindingTy = std::pair<Loc, SVal>;
351 using BindingsTy = SmallVectorImpl<FrameBindingTy>;
353 /// Populates the given SmallVector with the bindings in the callee's stack
354 /// frame at the start of this call.
355 virtual void getInitialStackFrameContents(const StackFrameContext *CalleeCtx,
356 BindingsTy &Bindings) const = 0;
358 /// Returns a copy of this CallEvent, but using the given state.
359 template <typename T>
360 CallEventRef<T> cloneWithState(ProgramStateRef NewState) const;
362 /// Returns a copy of this CallEvent, but using the given state.
363 CallEventRef<> cloneWithState(ProgramStateRef NewState) const {
364 return cloneWithState<CallEvent>(NewState);
367 /// Returns true if this is a statement is a function or method call
369 static bool isCallStmt(const Stmt *S);
371 /// Returns the result type of a function or method declaration.
373 /// This will return a null QualType if the result type cannot be determined.
374 static QualType getDeclaredResultType(const Decl *D);
376 /// Returns true if the given decl is known to be variadic.
378 /// \p D must not be null.
379 static bool isVariadic(const Decl *D);
381 /// Returns AnalysisDeclContext for the callee stack frame.
382 /// Currently may fail; returns null on failure.
383 AnalysisDeclContext *getCalleeAnalysisDeclContext() const;
385 /// Returns the callee stack frame. That stack frame will only be entered
386 /// during analysis if the call is inlined, but it may still be useful
387 /// in intermediate calculations even if the call isn't inlined.
388 /// May fail; returns null on failure.
389 const StackFrameContext *getCalleeStackFrame() const;
391 /// Returns memory location for a parameter variable within the callee stack
392 /// frame. May fail; returns null on failure.
393 const VarRegion *getParameterLocation(unsigned Index) const;
395 /// Returns true if on the current path, the argument was constructed by
396 /// calling a C++ constructor over it. This is an internal detail of the
397 /// analysis which doesn't necessarily represent the program semantics:
398 /// if we are supposed to construct an argument directly, we may still
399 /// not do that because we don't know how (i.e., construction context is
400 /// unavailable in the CFG or not supported by the analyzer).
401 bool isArgumentConstructedDirectly(unsigned Index) const {
402 // This assumes that the object was not yet removed from the state.
403 return ExprEngine::getObjectUnderConstruction(
404 getState(), {getOriginExpr(), Index}, getLocationContext()).hasValue();
407 /// Some calls have parameter numbering mismatched from argument numbering.
408 /// This function converts an argument index to the corresponding
409 /// parameter index. Returns None is the argument doesn't correspond
410 /// to any parameter variable.
411 virtual Optional<unsigned>
412 getAdjustedParameterIndex(unsigned ASTArgumentIndex) const {
413 return ASTArgumentIndex;
416 /// Some call event sub-classes conveniently adjust mismatching AST indices
417 /// to match parameter indices. This function converts an argument index
418 /// as understood by CallEvent to the argument index as understood by the AST.
419 virtual unsigned getASTArgumentIndex(unsigned CallArgumentIndex) const {
420 return CallArgumentIndex;
423 // Iterator access to formal parameters and their types.
426 QualType operator()(ParmVarDecl *PD) const { return PD->getType(); }
430 /// Return call's formal parameters.
432 /// Remember that the number of formal parameters may not match the number
433 /// of arguments for all calls. However, the first parameter will always
434 /// correspond with the argument value returned by \c getArgSVal(0).
435 virtual ArrayRef<ParmVarDecl *> parameters() const = 0;
437 using param_type_iterator =
438 llvm::mapped_iterator<ArrayRef<ParmVarDecl *>::iterator, GetTypeFn>;
440 /// Returns an iterator over the types of the call's formal parameters.
442 /// This uses the callee decl found by default name lookup rather than the
443 /// definition because it represents a public interface, and probably has
444 /// more annotations.
445 param_type_iterator param_type_begin() const {
446 return llvm::map_iterator(parameters().begin(), GetTypeFn());
448 /// \sa param_type_begin()
449 param_type_iterator param_type_end() const {
450 return llvm::map_iterator(parameters().end(), GetTypeFn());
453 // For debugging purposes only
454 void dump(raw_ostream &Out) const;
458 /// Represents a call to any sort of function that might have a
460 class AnyFunctionCall : public CallEvent {
462 AnyFunctionCall(const Expr *E, ProgramStateRef St,
463 const LocationContext *LCtx)
464 : CallEvent(E, St, LCtx) {}
465 AnyFunctionCall(const Decl *D, ProgramStateRef St,
466 const LocationContext *LCtx)
467 : CallEvent(D, St, LCtx) {}
468 AnyFunctionCall(const AnyFunctionCall &Other) = default;
471 // This function is overridden by subclasses, but they must return
473 const FunctionDecl *getDecl() const override {
474 return cast<FunctionDecl>(CallEvent::getDecl());
477 RuntimeDefinition getRuntimeDefinition() const override;
479 bool argumentsMayEscape() const override;
481 void getInitialStackFrameContents(const StackFrameContext *CalleeCtx,
482 BindingsTy &Bindings) const override;
484 ArrayRef<ParmVarDecl *> parameters() const override;
486 static bool classof(const CallEvent *CA) {
487 return CA->getKind() >= CE_BEG_FUNCTION_CALLS &&
488 CA->getKind() <= CE_END_FUNCTION_CALLS;
492 /// Represents a C function or static C++ member function call.
494 /// Example: \c fun()
495 class SimpleFunctionCall : public AnyFunctionCall {
496 friend class CallEventManager;
499 SimpleFunctionCall(const CallExpr *CE, ProgramStateRef St,
500 const LocationContext *LCtx)
501 : AnyFunctionCall(CE, St, LCtx) {}
502 SimpleFunctionCall(const SimpleFunctionCall &Other) = default;
504 void cloneTo(void *Dest) const override {
505 new (Dest) SimpleFunctionCall(*this);
509 virtual const CallExpr *getOriginExpr() const {
510 return cast<CallExpr>(AnyFunctionCall::getOriginExpr());
513 const FunctionDecl *getDecl() const override;
515 unsigned getNumArgs() const override { return getOriginExpr()->getNumArgs(); }
517 const Expr *getArgExpr(unsigned Index) const override {
518 return getOriginExpr()->getArg(Index);
521 Kind getKind() const override { return CE_Function; }
523 static bool classof(const CallEvent *CA) {
524 return CA->getKind() == CE_Function;
528 /// Represents a call to a block.
530 /// Example: <tt>^{ /* ... */ }()</tt>
531 class BlockCall : public CallEvent {
532 friend class CallEventManager;
535 BlockCall(const CallExpr *CE, ProgramStateRef St,
536 const LocationContext *LCtx)
537 : CallEvent(CE, St, LCtx) {}
538 BlockCall(const BlockCall &Other) = default;
540 void cloneTo(void *Dest) const override { new (Dest) BlockCall(*this); }
542 void getExtraInvalidatedValues(ValueList &Values,
543 RegionAndSymbolInvalidationTraits *ETraits) const override;
546 virtual const CallExpr *getOriginExpr() const {
547 return cast<CallExpr>(CallEvent::getOriginExpr());
550 unsigned getNumArgs() const override { return getOriginExpr()->getNumArgs(); }
552 const Expr *getArgExpr(unsigned Index) const override {
553 return getOriginExpr()->getArg(Index);
556 /// Returns the region associated with this instance of the block.
558 /// This may be NULL if the block's origin is unknown.
559 const BlockDataRegion *getBlockRegion() const;
561 const BlockDecl *getDecl() const override {
562 const BlockDataRegion *BR = getBlockRegion();
565 return BR->getDecl();
568 bool isConversionFromLambda() const {
569 const BlockDecl *BD = getDecl();
573 return BD->isConversionFromLambda();
576 /// For a block converted from a C++ lambda, returns the block
577 /// VarRegion for the variable holding the captured C++ lambda record.
578 const VarRegion *getRegionStoringCapturedLambda() const {
579 assert(isConversionFromLambda());
580 const BlockDataRegion *BR = getBlockRegion();
581 assert(BR && "Block converted from lambda must have a block region");
583 auto I = BR->referenced_vars_begin();
584 assert(I != BR->referenced_vars_end());
586 return I.getCapturedRegion();
589 RuntimeDefinition getRuntimeDefinition() const override {
590 if (!isConversionFromLambda())
591 return RuntimeDefinition(getDecl());
593 // Clang converts lambdas to blocks with an implicit user-defined
594 // conversion operator method on the lambda record that looks (roughly)
597 // typedef R(^block_type)(P1, P2, ...);
598 // operator block_type() const {
599 // auto Lambda = *this;
600 // return ^(P1 p1, P2 p2, ...){
601 // /* return Lambda(p1, p2, ...); */
605 // Here R is the return type of the lambda and P1, P2, ... are
606 // its parameter types. 'Lambda' is a fake VarDecl captured by the block
607 // that is initialized to a copy of the lambda.
609 // Sema leaves the body of a lambda-converted block empty (it is
610 // produced by CodeGen), so we can't analyze it directly. Instead, we skip
611 // the block body and analyze the operator() method on the captured lambda.
612 const VarDecl *LambdaVD = getRegionStoringCapturedLambda()->getDecl();
613 const CXXRecordDecl *LambdaDecl = LambdaVD->getType()->getAsCXXRecordDecl();
614 CXXMethodDecl* LambdaCallOperator = LambdaDecl->getLambdaCallOperator();
616 return RuntimeDefinition(LambdaCallOperator);
619 bool argumentsMayEscape() const override {
623 void getInitialStackFrameContents(const StackFrameContext *CalleeCtx,
624 BindingsTy &Bindings) const override;
626 ArrayRef<ParmVarDecl*> parameters() const override;
628 Kind getKind() const override { return CE_Block; }
630 static bool classof(const CallEvent *CA) {
631 return CA->getKind() == CE_Block;
635 /// Represents a non-static C++ member function call, no matter how
637 class CXXInstanceCall : public AnyFunctionCall {
639 CXXInstanceCall(const CallExpr *CE, ProgramStateRef St,
640 const LocationContext *LCtx)
641 : AnyFunctionCall(CE, St, LCtx) {}
642 CXXInstanceCall(const FunctionDecl *D, ProgramStateRef St,
643 const LocationContext *LCtx)
644 : AnyFunctionCall(D, St, LCtx) {}
645 CXXInstanceCall(const CXXInstanceCall &Other) = default;
647 void getExtraInvalidatedValues(ValueList &Values,
648 RegionAndSymbolInvalidationTraits *ETraits) const override;
651 /// Returns the expression representing the implicit 'this' object.
652 virtual const Expr *getCXXThisExpr() const { return nullptr; }
654 /// Returns the value of the implicit 'this' object.
655 virtual SVal getCXXThisVal() const;
657 const FunctionDecl *getDecl() const override;
659 RuntimeDefinition getRuntimeDefinition() const override;
661 void getInitialStackFrameContents(const StackFrameContext *CalleeCtx,
662 BindingsTy &Bindings) const override;
664 static bool classof(const CallEvent *CA) {
665 return CA->getKind() >= CE_BEG_CXX_INSTANCE_CALLS &&
666 CA->getKind() <= CE_END_CXX_INSTANCE_CALLS;
670 /// Represents a non-static C++ member function call.
672 /// Example: \c obj.fun()
673 class CXXMemberCall : public CXXInstanceCall {
674 friend class CallEventManager;
677 CXXMemberCall(const CXXMemberCallExpr *CE, ProgramStateRef St,
678 const LocationContext *LCtx)
679 : CXXInstanceCall(CE, St, LCtx) {}
680 CXXMemberCall(const CXXMemberCall &Other) = default;
682 void cloneTo(void *Dest) const override { new (Dest) CXXMemberCall(*this); }
685 virtual const CXXMemberCallExpr *getOriginExpr() const {
686 return cast<CXXMemberCallExpr>(CXXInstanceCall::getOriginExpr());
689 unsigned getNumArgs() const override {
690 if (const CallExpr *CE = getOriginExpr())
691 return CE->getNumArgs();
695 const Expr *getArgExpr(unsigned Index) const override {
696 return getOriginExpr()->getArg(Index);
699 const Expr *getCXXThisExpr() const override;
701 RuntimeDefinition getRuntimeDefinition() const override;
703 Kind getKind() const override { return CE_CXXMember; }
705 static bool classof(const CallEvent *CA) {
706 return CA->getKind() == CE_CXXMember;
710 /// Represents a C++ overloaded operator call where the operator is
711 /// implemented as a non-static member function.
713 /// Example: <tt>iter + 1</tt>
714 class CXXMemberOperatorCall : public CXXInstanceCall {
715 friend class CallEventManager;
718 CXXMemberOperatorCall(const CXXOperatorCallExpr *CE, ProgramStateRef St,
719 const LocationContext *LCtx)
720 : CXXInstanceCall(CE, St, LCtx) {}
721 CXXMemberOperatorCall(const CXXMemberOperatorCall &Other) = default;
723 void cloneTo(void *Dest) const override {
724 new (Dest) CXXMemberOperatorCall(*this);
728 virtual const CXXOperatorCallExpr *getOriginExpr() const {
729 return cast<CXXOperatorCallExpr>(CXXInstanceCall::getOriginExpr());
732 unsigned getNumArgs() const override {
733 return getOriginExpr()->getNumArgs() - 1;
736 const Expr *getArgExpr(unsigned Index) const override {
737 return getOriginExpr()->getArg(Index + 1);
740 const Expr *getCXXThisExpr() const override;
742 Kind getKind() const override { return CE_CXXMemberOperator; }
744 static bool classof(const CallEvent *CA) {
745 return CA->getKind() == CE_CXXMemberOperator;
749 getAdjustedParameterIndex(unsigned ASTArgumentIndex) const override {
750 // For member operator calls argument 0 on the expression corresponds
751 // to implicit this-parameter on the declaration.
752 return (ASTArgumentIndex > 0) ? Optional<unsigned>(ASTArgumentIndex - 1)
756 unsigned getASTArgumentIndex(unsigned CallArgumentIndex) const override {
757 // For member operator calls argument 0 on the expression corresponds
758 // to implicit this-parameter on the declaration.
759 return CallArgumentIndex + 1;
763 /// Represents an implicit call to a C++ destructor.
765 /// This can occur at the end of a scope (for automatic objects), at the end
766 /// of a full-expression (for temporaries), or as part of a delete.
767 class CXXDestructorCall : public CXXInstanceCall {
768 friend class CallEventManager;
771 using DtorDataTy = llvm::PointerIntPair<const MemRegion *, 1, bool>;
773 /// Creates an implicit destructor.
775 /// \param DD The destructor that will be called.
776 /// \param Trigger The statement whose completion causes this destructor call.
777 /// \param Target The object region to be destructed.
778 /// \param St The path-sensitive state at this point in the program.
779 /// \param LCtx The location context at this point in the program.
780 CXXDestructorCall(const CXXDestructorDecl *DD, const Stmt *Trigger,
781 const MemRegion *Target, bool IsBaseDestructor,
782 ProgramStateRef St, const LocationContext *LCtx)
783 : CXXInstanceCall(DD, St, LCtx) {
784 Data = DtorDataTy(Target, IsBaseDestructor).getOpaqueValue();
785 Location = Trigger->getEndLoc();
788 CXXDestructorCall(const CXXDestructorCall &Other) = default;
790 void cloneTo(void *Dest) const override {new (Dest) CXXDestructorCall(*this);}
793 SourceRange getSourceRange() const override { return Location; }
794 unsigned getNumArgs() const override { return 0; }
796 RuntimeDefinition getRuntimeDefinition() const override;
798 /// Returns the value of the implicit 'this' object.
799 SVal getCXXThisVal() const override;
801 /// Returns true if this is a call to a base class destructor.
802 bool isBaseDestructor() const {
803 return DtorDataTy::getFromOpaqueValue(Data).getInt();
806 Kind getKind() const override { return CE_CXXDestructor; }
808 static bool classof(const CallEvent *CA) {
809 return CA->getKind() == CE_CXXDestructor;
813 /// Represents a call to a C++ constructor.
816 class CXXConstructorCall : public AnyFunctionCall {
817 friend class CallEventManager;
820 /// Creates a constructor call.
822 /// \param CE The constructor expression as written in the source.
823 /// \param Target The region where the object should be constructed. If NULL,
824 /// a new symbolic region will be used.
825 /// \param St The path-sensitive state at this point in the program.
826 /// \param LCtx The location context at this point in the program.
827 CXXConstructorCall(const CXXConstructExpr *CE, const MemRegion *Target,
828 ProgramStateRef St, const LocationContext *LCtx)
829 : AnyFunctionCall(CE, St, LCtx) {
833 CXXConstructorCall(const CXXConstructorCall &Other) = default;
835 void cloneTo(void *Dest) const override { new (Dest) CXXConstructorCall(*this); }
837 void getExtraInvalidatedValues(ValueList &Values,
838 RegionAndSymbolInvalidationTraits *ETraits) const override;
841 virtual const CXXConstructExpr *getOriginExpr() const {
842 return cast<CXXConstructExpr>(AnyFunctionCall::getOriginExpr());
845 const CXXConstructorDecl *getDecl() const override {
846 return getOriginExpr()->getConstructor();
849 unsigned getNumArgs() const override { return getOriginExpr()->getNumArgs(); }
851 const Expr *getArgExpr(unsigned Index) const override {
852 return getOriginExpr()->getArg(Index);
855 /// Returns the value of the implicit 'this' object.
856 SVal getCXXThisVal() const;
858 void getInitialStackFrameContents(const StackFrameContext *CalleeCtx,
859 BindingsTy &Bindings) const override;
861 Kind getKind() const override { return CE_CXXConstructor; }
863 static bool classof(const CallEvent *CA) {
864 return CA->getKind() == CE_CXXConstructor;
868 /// Represents the memory allocation call in a C++ new-expression.
870 /// This is a call to "operator new".
871 class CXXAllocatorCall : public AnyFunctionCall {
872 friend class CallEventManager;
875 CXXAllocatorCall(const CXXNewExpr *E, ProgramStateRef St,
876 const LocationContext *LCtx)
877 : AnyFunctionCall(E, St, LCtx) {}
878 CXXAllocatorCall(const CXXAllocatorCall &Other) = default;
880 void cloneTo(void *Dest) const override { new (Dest) CXXAllocatorCall(*this); }
883 virtual const CXXNewExpr *getOriginExpr() const {
884 return cast<CXXNewExpr>(AnyFunctionCall::getOriginExpr());
887 const FunctionDecl *getDecl() const override {
888 return getOriginExpr()->getOperatorNew();
891 /// Number of non-placement arguments to the call. It is equal to 2 for
892 /// C++17 aligned operator new() calls that have alignment implicitly
893 /// passed as the second argument, and to 1 for other operator new() calls.
894 unsigned getNumImplicitArgs() const {
895 return getOriginExpr()->passAlignment() ? 2 : 1;
898 unsigned getNumArgs() const override {
899 return getOriginExpr()->getNumPlacementArgs() + getNumImplicitArgs();
902 const Expr *getArgExpr(unsigned Index) const override {
903 // The first argument of an allocator call is the size of the allocation.
904 if (Index < getNumImplicitArgs())
906 return getOriginExpr()->getPlacementArg(Index - getNumImplicitArgs());
909 /// Number of placement arguments to the operator new() call. For example,
910 /// standard std::nothrow operator new and standard placement new both have
911 /// 1 implicit argument (size) and 1 placement argument, while regular
912 /// operator new() has 1 implicit argument and 0 placement arguments.
913 const Expr *getPlacementArgExpr(unsigned Index) const {
914 return getOriginExpr()->getPlacementArg(Index);
917 Kind getKind() const override { return CE_CXXAllocator; }
919 static bool classof(const CallEvent *CE) {
920 return CE->getKind() == CE_CXXAllocator;
924 /// Represents the ways an Objective-C message send can occur.
926 // Note to maintainers: OCM_Message should always be last, since it does not
927 // need to fit in the Data field's low bits.
928 enum ObjCMessageKind {
934 /// Represents any expression that calls an Objective-C method.
936 /// This includes all of the kinds listed in ObjCMessageKind.
937 class ObjCMethodCall : public CallEvent {
938 friend class CallEventManager;
940 const PseudoObjectExpr *getContainingPseudoObjectExpr() const;
943 ObjCMethodCall(const ObjCMessageExpr *Msg, ProgramStateRef St,
944 const LocationContext *LCtx)
945 : CallEvent(Msg, St, LCtx) {
949 ObjCMethodCall(const ObjCMethodCall &Other) = default;
951 void cloneTo(void *Dest) const override { new (Dest) ObjCMethodCall(*this); }
953 void getExtraInvalidatedValues(ValueList &Values,
954 RegionAndSymbolInvalidationTraits *ETraits) const override;
956 /// Check if the selector may have multiple definitions (may have overrides).
957 virtual bool canBeOverridenInSubclass(ObjCInterfaceDecl *IDecl,
961 virtual const ObjCMessageExpr *getOriginExpr() const {
962 return cast<ObjCMessageExpr>(CallEvent::getOriginExpr());
965 const ObjCMethodDecl *getDecl() const override {
966 return getOriginExpr()->getMethodDecl();
969 unsigned getNumArgs() const override {
970 return getOriginExpr()->getNumArgs();
973 const Expr *getArgExpr(unsigned Index) const override {
974 return getOriginExpr()->getArg(Index);
977 bool isInstanceMessage() const {
978 return getOriginExpr()->isInstanceMessage();
981 ObjCMethodFamily getMethodFamily() const {
982 return getOriginExpr()->getMethodFamily();
985 Selector getSelector() const {
986 return getOriginExpr()->getSelector();
989 SourceRange getSourceRange() const override;
991 /// Returns the value of the receiver at the time of this call.
992 SVal getReceiverSVal() const;
994 /// Return the value of 'self' if available.
995 SVal getSelfSVal() const;
997 /// Get the interface for the receiver.
999 /// This works whether this is an instance message or a class message.
1000 /// However, it currently just uses the static type of the receiver.
1001 const ObjCInterfaceDecl *getReceiverInterface() const {
1002 return getOriginExpr()->getReceiverInterface();
1005 /// Checks if the receiver refers to 'self' or 'super'.
1006 bool isReceiverSelfOrSuper() const;
1008 /// Returns how the message was written in the source (property access,
1009 /// subscript, or explicit message send).
1010 ObjCMessageKind getMessageKind() const;
1012 /// Returns true if this property access or subscript is a setter (has the
1013 /// form of an assignment).
1014 bool isSetter() const {
1015 switch (getMessageKind()) {
1017 llvm_unreachable("This is not a pseudo-object access!");
1018 case OCM_PropertyAccess:
1019 return getNumArgs() > 0;
1021 return getNumArgs() > 1;
1023 llvm_unreachable("Unknown message kind");
1026 // Returns the property accessed by this method, either explicitly via
1027 // property syntax or implicitly via a getter or setter method. Returns
1028 // nullptr if the call is not a prooperty access.
1029 const ObjCPropertyDecl *getAccessedProperty() const;
1031 RuntimeDefinition getRuntimeDefinition() const override;
1033 bool argumentsMayEscape() const override;
1035 void getInitialStackFrameContents(const StackFrameContext *CalleeCtx,
1036 BindingsTy &Bindings) const override;
1038 ArrayRef<ParmVarDecl*> parameters() const override;
1040 Kind getKind() const override { return CE_ObjCMessage; }
1042 static bool classof(const CallEvent *CA) {
1043 return CA->getKind() == CE_ObjCMessage;
1047 enum CallDescriptionFlags : int {
1048 /// Describes a C standard function that is sometimes implemented as a macro
1049 /// that expands to a compiler builtin with some __builtin prefix.
1050 /// The builtin may as well have a few extra arguments on top of the requested
1051 /// number of arguments.
1052 CDF_MaybeBuiltin = 1 << 0,
1055 /// This class represents a description of a function call using the number of
1056 /// arguments and the name of the function.
1057 class CallDescription {
1060 mutable IdentifierInfo *II = nullptr;
1061 mutable bool IsLookupDone = false;
1062 // The list of the qualified names used to identify the specified CallEvent,
1063 // e.g. "{a, b}" represent the qualified names, like "a::b".
1064 std::vector<const char *> QualifiedName;
1065 Optional<unsigned> RequiredArgs;
1069 /// Constructs a CallDescription object.
1071 /// @param QualifiedName The list of the name qualifiers of the function that
1072 /// will be matched. The user is allowed to skip any of the qualifiers.
1073 /// For example, {"std", "basic_string", "c_str"} would match both
1074 /// std::basic_string<...>::c_str() and std::__1::basic_string<...>::c_str().
1076 /// @param RequiredArgs The number of arguments that is expected to match a
1077 /// call. Omit this parameter to match every occurrence of call with a given
1078 /// name regardless the number of arguments.
1079 CallDescription(int Flags, ArrayRef<const char *> QualifiedName,
1080 Optional<unsigned> RequiredArgs = None)
1081 : QualifiedName(QualifiedName), RequiredArgs(RequiredArgs),
1084 /// Construct a CallDescription with default flags.
1085 CallDescription(ArrayRef<const char *> QualifiedName,
1086 Optional<unsigned> RequiredArgs = None)
1087 : CallDescription(0, QualifiedName, RequiredArgs) {}
1089 /// Get the name of the function that this object matches.
1090 StringRef getFunctionName() const { return QualifiedName.back(); }
1093 /// An immutable map from CallDescriptions to arbitrary data. Provides a unified
1094 /// way for checkers to react on function calls.
1095 template <typename T> class CallDescriptionMap {
1096 // Some call descriptions aren't easily hashable (eg., the ones with qualified
1097 // names in which some sections are omitted), so let's put them
1098 // in a simple vector and use linear lookup.
1099 // TODO: Implement an actual map for fast lookup for "hashable" call
1100 // descriptions (eg., the ones for C functions that just match the name).
1101 std::vector<std::pair<CallDescription, T>> LinearMap;
1105 std::initializer_list<std::pair<CallDescription, T>> &&List)
1106 : LinearMap(List) {}
1108 ~CallDescriptionMap() = default;
1110 // These maps are usually stored once per checker, so let's make sure
1111 // we don't do redundant copies.
1112 CallDescriptionMap(const CallDescriptionMap &) = delete;
1113 CallDescriptionMap &operator=(const CallDescription &) = delete;
1115 const T *lookup(const CallEvent &Call) const {
1116 // Slow path: linear lookup.
1117 // TODO: Implement some sort of fast path.
1118 for (const std::pair<CallDescription, T> &I : LinearMap)
1119 if (Call.isCalled(I.first))
1126 /// Manages the lifetime of CallEvent objects.
1128 /// CallEventManager provides a way to create arbitrary CallEvents "on the
1129 /// stack" as if they were value objects by keeping a cache of CallEvent-sized
1130 /// memory blocks. The CallEvents created by CallEventManager are only valid
1131 /// for the lifetime of the OwnedCallEvent that holds them; right now these
1132 /// objects cannot be copied and ownership cannot be transferred.
1133 class CallEventManager {
1134 friend class CallEvent;
1136 llvm::BumpPtrAllocator &Alloc;
1137 SmallVector<void *, 8> Cache;
1139 using CallEventTemplateTy = SimpleFunctionCall;
1141 void reclaim(const void *Memory) {
1142 Cache.push_back(const_cast<void *>(Memory));
1145 /// Returns memory that can be initialized as a CallEvent.
1148 return Alloc.Allocate<CallEventTemplateTy>();
1150 return Cache.pop_back_val();
1153 template <typename T, typename Arg>
1154 T *create(Arg A, ProgramStateRef St, const LocationContext *LCtx) {
1155 static_assert(sizeof(T) == sizeof(CallEventTemplateTy),
1156 "CallEvent subclasses are not all the same size");
1157 return new (allocate()) T(A, St, LCtx);
1160 template <typename T, typename Arg1, typename Arg2>
1161 T *create(Arg1 A1, Arg2 A2, ProgramStateRef St, const LocationContext *LCtx) {
1162 static_assert(sizeof(T) == sizeof(CallEventTemplateTy),
1163 "CallEvent subclasses are not all the same size");
1164 return new (allocate()) T(A1, A2, St, LCtx);
1167 template <typename T, typename Arg1, typename Arg2, typename Arg3>
1168 T *create(Arg1 A1, Arg2 A2, Arg3 A3, ProgramStateRef St,
1169 const LocationContext *LCtx) {
1170 static_assert(sizeof(T) == sizeof(CallEventTemplateTy),
1171 "CallEvent subclasses are not all the same size");
1172 return new (allocate()) T(A1, A2, A3, St, LCtx);
1175 template <typename T, typename Arg1, typename Arg2, typename Arg3,
1177 T *create(Arg1 A1, Arg2 A2, Arg3 A3, Arg4 A4, ProgramStateRef St,
1178 const LocationContext *LCtx) {
1179 static_assert(sizeof(T) == sizeof(CallEventTemplateTy),
1180 "CallEvent subclasses are not all the same size");
1181 return new (allocate()) T(A1, A2, A3, A4, St, LCtx);
1185 CallEventManager(llvm::BumpPtrAllocator &alloc) : Alloc(alloc) {}
1187 /// Gets an outside caller given a callee context.
1189 getCaller(const StackFrameContext *CalleeCtx, ProgramStateRef State);
1191 /// Gets a call event for a function call, Objective-C method call,
1192 /// or a 'new' call.
1194 getCall(const Stmt *S, ProgramStateRef State,
1195 const LocationContext *LC);
1198 getSimpleCall(const CallExpr *E, ProgramStateRef State,
1199 const LocationContext *LCtx);
1201 CallEventRef<ObjCMethodCall>
1202 getObjCMethodCall(const ObjCMessageExpr *E, ProgramStateRef State,
1203 const LocationContext *LCtx) {
1204 return create<ObjCMethodCall>(E, State, LCtx);
1207 CallEventRef<CXXConstructorCall>
1208 getCXXConstructorCall(const CXXConstructExpr *E, const MemRegion *Target,
1209 ProgramStateRef State, const LocationContext *LCtx) {
1210 return create<CXXConstructorCall>(E, Target, State, LCtx);
1213 CallEventRef<CXXDestructorCall>
1214 getCXXDestructorCall(const CXXDestructorDecl *DD, const Stmt *Trigger,
1215 const MemRegion *Target, bool IsBase,
1216 ProgramStateRef State, const LocationContext *LCtx) {
1217 return create<CXXDestructorCall>(DD, Trigger, Target, IsBase, State, LCtx);
1220 CallEventRef<CXXAllocatorCall>
1221 getCXXAllocatorCall(const CXXNewExpr *E, ProgramStateRef State,
1222 const LocationContext *LCtx) {
1223 return create<CXXAllocatorCall>(E, State, LCtx);
1227 template <typename T>
1228 CallEventRef<T> CallEvent::cloneWithState(ProgramStateRef NewState) const {
1229 assert(isa<T>(*this) && "Cloning to unrelated type");
1230 static_assert(sizeof(T) == sizeof(CallEvent),
1231 "Subclasses may not add fields");
1233 if (NewState == State)
1234 return cast<T>(this);
1236 CallEventManager &Mgr = State->getStateManager().getCallEventManager();
1237 T *Copy = static_cast<T *>(Mgr.allocate());
1239 assert(Copy->getKind() == this->getKind() && "Bad copy");
1241 Copy->State = NewState;
1245 inline void CallEvent::Release() const {
1246 assert(RefCount > 0 && "Reference count is already zero.");
1252 CallEventManager &Mgr = State->getStateManager().getCallEventManager();
1260 } // namespace clang
1264 // Support isa<>, cast<>, and dyn_cast<> for CallEventRef.
1265 template<class T> struct simplify_type< clang::ento::CallEventRef<T>> {
1266 using SimpleType = const T *;
1269 getSimplifiedValue(clang::ento::CallEventRef<T> Val) {
1276 #endif // LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_CALLEVENT_H