1//===- CallEvent.h - Wrapper for all function and method calls --*- 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/// \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).
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_CALLEVENT_H
16#define LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_CALLEVENT_H
17
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/ADT/iterator_range.h"
43#include "llvm/Support/Allocator.h"
44#include "llvm/Support/Casting.h"
45#include "llvm/Support/ErrorHandling.h"
46#include <cassert>
47#include <limits>
48#include <utility>
49
50namespace clang {
51
52class LocationContext;
53class ProgramPoint;
54class ProgramPointTag;
55class StackFrameContext;
56
57namespace ento {
58
59enum CallEventKind {
60 CE_Function,
61 CE_CXXMember,
62 CE_CXXMemberOperator,
63 CE_CXXDestructor,
64 CE_BEG_CXX_INSTANCE_CALLS = CE_CXXMember,
65 CE_END_CXX_INSTANCE_CALLS = CE_CXXDestructor,
66 CE_CXXConstructor,
67 CE_CXXInheritedConstructor,
68 CE_BEG_CXX_CONSTRUCTOR_CALLS = CE_CXXConstructor,
69 CE_END_CXX_CONSTRUCTOR_CALLS = CE_CXXInheritedConstructor,
70 CE_CXXAllocator,
71 CE_CXXDeallocator,
72 CE_BEG_FUNCTION_CALLS = CE_Function,
73 CE_END_FUNCTION_CALLS = CE_CXXDeallocator,
74 CE_Block,
75 CE_ObjCMessage
76};
77
78class CallEvent;
79class CallDescription;
80
81template<typename T = CallEvent>
82class CallEventRef : public IntrusiveRefCntPtr<const T> {
83public:
84 CallEventRef(const T *Call) : IntrusiveRefCntPtr<const T>(Call) {}
85 CallEventRef(const CallEventRef &Orig) : IntrusiveRefCntPtr<const T>(Orig) {}
86
87 CallEventRef<T> cloneWithState(ProgramStateRef State) const {
88 return this->get()->template cloneWithState<T>(State);
89 }
90
91 // Allow implicit conversions to a superclass type, since CallEventRef
92 // behaves like a pointer-to-const.
93 template <typename SuperT>
94 operator CallEventRef<SuperT> () const {
95 return this->get();
96 }
97};
98
99/// \class RuntimeDefinition
100/// Defines the runtime definition of the called function.
101///
102/// Encapsulates the information we have about which Decl will be used
103/// when the call is executed on the given path. When dealing with dynamic
104/// dispatch, the information is based on DynamicTypeInfo and might not be
105/// precise.
106class RuntimeDefinition {
107 /// The Declaration of the function which could be called at runtime.
108 /// NULL if not available.
109 const Decl *D = nullptr;
110
111 /// The region representing an object (ObjC/C++) on which the method is
112 /// called. With dynamic dispatch, the method definition depends on the
113 /// runtime type of this object. NULL when the DynamicTypeInfo is
114 /// precise.
115 const MemRegion *R = nullptr;
116
117public:
118 RuntimeDefinition() = default;
119 RuntimeDefinition(const Decl *InD): D(InD) {}
120 RuntimeDefinition(const Decl *InD, const MemRegion *InR): D(InD), R(InR) {}
121
122 const Decl *getDecl() { return D; }
123
124 /// Check if the definition we have is precise.
125 /// If not, it is possible that the call dispatches to another definition at
126 /// execution time.
127 bool mayHaveOtherDefinitions() { return R != nullptr; }
128
129 /// When other definitions are possible, returns the region whose runtime type
130 /// determines the method definition.
131 const MemRegion *getDispatchRegion() { return R; }
132};
133
134/// Represents an abstract call to a function or method along a
135/// particular path.
136///
137/// CallEvents are created through the factory methods of CallEventManager.
138///
139/// CallEvents should always be cheap to create and destroy. In order for
140/// CallEventManager to be able to re-use CallEvent-sized memory blocks,
141/// subclasses of CallEvent may not add any data members to the base class.
142/// Use the "Data" and "Location" fields instead.
143class CallEvent {
144public:
145 using Kind = CallEventKind;
146
147private:
148 ProgramStateRef State;
149 const LocationContext *LCtx;
150 llvm::PointerUnion<const Expr *, const Decl *> Origin;
151
152protected:
153 // This is user data for subclasses.
154 const void *Data;
155
156 // This is user data for subclasses.
157 // This should come right before RefCount, so that the two fields can be
158 // packed together on LP64 platforms.
159 SourceLocation Location;
160
161private:
162 template <typename T> friend struct llvm::IntrusiveRefCntPtrInfo;
163
164 mutable unsigned RefCount = 0;
165
166 void Retain() const { ++RefCount; }
167 void Release() const;
168
169protected:
170 friend class CallEventManager;
171
172 CallEvent(const Expr *E, ProgramStateRef state, const LocationContext *lctx)
173 : State(std::move(state)), LCtx(lctx), Origin(E) {}
174
175 CallEvent(const Decl *D, ProgramStateRef state, const LocationContext *lctx)
176 : State(std::move(state)), LCtx(lctx), Origin(D) {}
177
178 // DO NOT MAKE PUBLIC
179 CallEvent(const CallEvent &Original)
180 : State(Original.State), LCtx(Original.LCtx), Origin(Original.Origin),
181 Data(Original.Data), Location(Original.Location) {}
182
183 /// Copies this CallEvent, with vtable intact, into a new block of memory.
184 virtual void cloneTo(void *Dest) const = 0;
185
186 /// Get the value of arbitrary expressions at this point in the path.
187 SVal getSVal(const Stmt *S) const {
188 return getState()->getSVal(S, getLocationContext());
189 }
190
191 using ValueList = SmallVectorImpl<SVal>;
192
193 /// Used to specify non-argument regions that will be invalidated as a
194 /// result of this call.
195 virtual void getExtraInvalidatedValues(ValueList &Values,
196 RegionAndSymbolInvalidationTraits *ETraits) const {}
197
198public:
199 CallEvent &operator=(const CallEvent &) = delete;
200 virtual ~CallEvent() = default;
201
202 /// Returns the kind of call this is.
203 virtual Kind getKind() const = 0;
204 virtual StringRef getKindAsString() const = 0;
205
206 /// Returns the declaration of the function or method that will be
207 /// called. May be null.
208 virtual const Decl *getDecl() const {
209 return Origin.dyn_cast<const Decl *>();
210 }
211
212 /// The state in which the call is being evaluated.
213 const ProgramStateRef &getState() const {
214 return State;
215 }
216
217 /// The context in which the call is being evaluated.
218 const LocationContext *getLocationContext() const {
219 return LCtx;
220 }
221
222 /// Returns the definition of the function or method that will be
223 /// called.
224 virtual RuntimeDefinition getRuntimeDefinition() const = 0;
225
226 /// Returns the expression whose value will be the result of this call.
227 /// May be null.
228 virtual const Expr *getOriginExpr() const {
229 return Origin.dyn_cast<const Expr *>();
230 }
231
232 /// Returns the number of arguments (explicit and implicit).
233 ///
234 /// Note that this may be greater than the number of parameters in the
235 /// callee's declaration, and that it may include arguments not written in
236 /// the source.
237 virtual unsigned getNumArgs() const = 0;
238
239 /// Returns true if the callee is known to be from a system header.
240 bool isInSystemHeader() const {
241 const Decl *D = getDecl();
242 if (!D)
243 return false;
244
245 SourceLocation Loc = D->getLocation();
246 if (Loc.isValid()) {
247 const SourceManager &SM =
248 getState()->getStateManager().getContext().getSourceManager();
249 return SM.isInSystemHeader(D->getLocation());
250 }
251
252 // Special case for implicitly-declared global operator new/delete.
253 // These should be considered system functions.
254 if (const auto *FD = dyn_cast<FunctionDecl>(D))
255 return FD->isOverloadedOperator() && FD->isImplicit() && FD->isGlobal();
256
257 return false;
258 }
259
260 /// Returns true if the CallEvent is a call to a function that matches
261 /// the CallDescription.
262 ///
263 /// Note that this function is not intended to be used to match Obj-C method
264 /// calls.
265 bool isCalled(const CallDescription &CD) const;
266
267 /// Returns true whether the CallEvent is any of the CallDescriptions supplied
268 /// as a parameter.
269 template <typename FirstCallDesc, typename... CallDescs>
270 bool isCalled(const FirstCallDesc &First, const CallDescs &... Rest) const {
271 return isCalled(First) || isCalled(Rest...);
272 }
273
274 /// Returns a source range for the entire call, suitable for
275 /// outputting in diagnostics.
276 virtual SourceRange getSourceRange() const {
277 return getOriginExpr()->getSourceRange();
278 }
279
280 /// Returns the value of a given argument at the time of the call.
281 virtual SVal getArgSVal(unsigned Index) const;
282
283 /// Returns the expression associated with a given argument.
284 /// May be null if this expression does not appear in the source.
285 virtual const Expr *getArgExpr(unsigned Index) const { return nullptr; }
286
287 /// Returns the source range for errors associated with this argument.
288 ///
289 /// May be invalid if the argument is not written in the source.
290 virtual SourceRange getArgSourceRange(unsigned Index) const;
291
292 /// Returns the result type, adjusted for references.
293 QualType getResultType() const;
294
295 /// Returns the return value of the call.
296 ///
297 /// This should only be called if the CallEvent was created using a state in
298 /// which the return value has already been bound to the origin expression.
299 SVal getReturnValue() const;
300
301 /// Returns true if the type of any of the non-null arguments satisfies
302 /// the condition.
303 bool hasNonNullArgumentsWithType(bool (*Condition)(QualType)) const;
304
305 /// Returns true if any of the arguments appear to represent callbacks.
306 bool hasNonZeroCallbackArg() const;
307
308 /// Returns true if any of the arguments is void*.
309 bool hasVoidPointerToNonConstArg() const;
310
311 /// Returns true if any of the arguments are known to escape to long-
312 /// term storage, even if this method will not modify them.
313 // NOTE: The exact semantics of this are still being defined!
314 // We don't really want a list of hardcoded exceptions in the long run,
315 // but we don't want duplicated lists of known APIs in the short term either.
316 virtual bool argumentsMayEscape() const {
317 return hasNonZeroCallbackArg();
318 }
319
320 /// Returns true if the callee is an externally-visible function in the
321 /// top-level namespace, such as \c malloc.
322 ///
323 /// You can use this call to determine that a particular function really is
324 /// a library function and not, say, a C++ member function with the same name.
325 ///
326 /// If a name is provided, the function must additionally match the given
327 /// name.
328 ///
329 /// Note that this deliberately excludes C++ library functions in the \c std
330 /// namespace, but will include C library functions accessed through the
331 /// \c std namespace. This also does not check if the function is declared
332 /// as 'extern "C"', or if it uses C++ name mangling.
333 // FIXME: Add a helper for checking namespaces.
334 // FIXME: Move this down to AnyFunctionCall once checkers have more
335 // precise callbacks.
336 bool isGlobalCFunction(StringRef SpecificName = StringRef()) const;
337
338 /// Returns the name of the callee, if its name is a simple identifier.
339 ///
340 /// Note that this will fail for Objective-C methods, blocks, and C++
341 /// overloaded operators. The former is named by a Selector rather than a
342 /// simple identifier, and the latter two do not have names.
343 // FIXME: Move this down to AnyFunctionCall once checkers have more
344 // precise callbacks.
345 const IdentifierInfo *getCalleeIdentifier() const {
346 const auto *ND = dyn_cast_or_null<NamedDecl>(getDecl());
347 if (!ND)
348 return nullptr;
349 return ND->getIdentifier();
350 }
351
352 /// Returns an appropriate ProgramPoint for this call.
353 ProgramPoint getProgramPoint(bool IsPreVisit = false,
354 const ProgramPointTag *Tag = nullptr) const;
355
356 /// Returns a new state with all argument regions invalidated.
357 ///
358 /// This accepts an alternate state in case some processing has already
359 /// occurred.
360 ProgramStateRef invalidateRegions(unsigned BlockCount,
361 ProgramStateRef Orig = nullptr) const;
362
363 using FrameBindingTy = std::pair<SVal, SVal>;
364 using BindingsTy = SmallVectorImpl<FrameBindingTy>;
365
366 /// Populates the given SmallVector with the bindings in the callee's stack
367 /// frame at the start of this call.
368 virtual void getInitialStackFrameContents(const StackFrameContext *CalleeCtx,
369 BindingsTy &Bindings) const = 0;
370
371 /// Returns a copy of this CallEvent, but using the given state.
372 template <typename T>
373 CallEventRef<T> cloneWithState(ProgramStateRef NewState) const;
374
375 /// Returns a copy of this CallEvent, but using the given state.
376 CallEventRef<> cloneWithState(ProgramStateRef NewState) const {
377 return cloneWithState<CallEvent>(NewState);
378 }
379
380 /// Returns true if this is a statement is a function or method call
381 /// of some kind.
382 static bool isCallStmt(const Stmt *S);
383
384 /// Returns the result type of a function or method declaration.
385 ///
386 /// This will return a null QualType if the result type cannot be determined.
387 static QualType getDeclaredResultType(const Decl *D);
388
389 /// Returns true if the given decl is known to be variadic.
390 ///
391 /// \p D must not be null.
392 static bool isVariadic(const Decl *D);
393
394 /// Returns AnalysisDeclContext for the callee stack frame.
395 /// Currently may fail; returns null on failure.
396 AnalysisDeclContext *getCalleeAnalysisDeclContext() const;
397
398 /// Returns the callee stack frame. That stack frame will only be entered
399 /// during analysis if the call is inlined, but it may still be useful
400 /// in intermediate calculations even if the call isn't inlined.
401 /// May fail; returns null on failure.
402 const StackFrameContext *getCalleeStackFrame(unsigned BlockCount) const;
403
404 /// Returns memory location for a parameter variable within the callee stack
405 /// frame. The behavior is undefined if the block count is different from the
406 /// one that is there when call happens. May fail; returns null on failure.
407 const ParamVarRegion *getParameterLocation(unsigned Index,
408 unsigned BlockCount) const;
409
410 /// Returns true if on the current path, the argument was constructed by
411 /// calling a C++ constructor over it. This is an internal detail of the
412 /// analysis which doesn't necessarily represent the program semantics:
413 /// if we are supposed to construct an argument directly, we may still
414 /// not do that because we don't know how (i.e., construction context is
415 /// unavailable in the CFG or not supported by the analyzer).
416 bool isArgumentConstructedDirectly(unsigned Index) const {
417 // This assumes that the object was not yet removed from the state.
418 return ExprEngine::getObjectUnderConstruction(
419 getState(), {getOriginExpr(), Index}, getLocationContext()).hasValue();
420 }
421
422 /// Some calls have parameter numbering mismatched from argument numbering.
423 /// This function converts an argument index to the corresponding
424 /// parameter index. Returns None is the argument doesn't correspond
425 /// to any parameter variable.
426 virtual Optional<unsigned>
427 getAdjustedParameterIndex(unsigned ASTArgumentIndex) const {
428 return ASTArgumentIndex;
429 }
430
431 /// Some call event sub-classes conveniently adjust mismatching AST indices
432 /// to match parameter indices. This function converts an argument index
433 /// as understood by CallEvent to the argument index as understood by the AST.
434 virtual unsigned getASTArgumentIndex(unsigned CallArgumentIndex) const {
435 return CallArgumentIndex;
436 }
437
438 /// Returns the construction context of the call, if it is a C++ constructor
439 /// call or a call of a function returning a C++ class instance. Otherwise
440 /// return nullptr.
441 const ConstructionContext *getConstructionContext() const;
442
443 /// If the call returns a C++ record type then the region of its return value
444 /// can be retrieved from its construction context.
445 Optional<SVal> getReturnValueUnderConstruction() const;
446
447 // Iterator access to formal parameters and their types.
448private:
449 struct GetTypeFn {
450 QualType operator()(ParmVarDecl *PD) const { return PD->getType(); }
451 };
452
453public:
454 /// Return call's formal parameters.
455 ///
456 /// Remember that the number of formal parameters may not match the number
457 /// of arguments for all calls. However, the first parameter will always
458 /// correspond with the argument value returned by \c getArgSVal(0).
459 virtual ArrayRef<ParmVarDecl *> parameters() const = 0;
460
461 using param_type_iterator =
462 llvm::mapped_iterator<ArrayRef<ParmVarDecl *>::iterator, GetTypeFn>;
463
464 /// Returns an iterator over the types of the call's formal parameters.
465 ///
466 /// This uses the callee decl found by default name lookup rather than the
467 /// definition because it represents a public interface, and probably has
468 /// more annotations.
469 param_type_iterator param_type_begin() const {
470 return llvm::map_iterator(parameters().begin(), GetTypeFn());
471 }
472 /// \sa param_type_begin()
473 param_type_iterator param_type_end() const {
474 return llvm::map_iterator(parameters().end(), GetTypeFn());
475 }
476
477 // For debugging purposes only
478 void dump(raw_ostream &Out) const;
479 void dump() const;
480};
481
482/// Represents a call to any sort of function that might have a
483/// FunctionDecl.
484class AnyFunctionCall : public CallEvent {
485protected:
486 AnyFunctionCall(const Expr *E, ProgramStateRef St,
487 const LocationContext *LCtx)
488 : CallEvent(E, St, LCtx) {}
489 AnyFunctionCall(const Decl *D, ProgramStateRef St,
490 const LocationContext *LCtx)
491 : CallEvent(D, St, LCtx) {}
492 AnyFunctionCall(const AnyFunctionCall &Other) = default;
493
494public:
495 // This function is overridden by subclasses, but they must return
496 // a FunctionDecl.
497 const FunctionDecl *getDecl() const override {
498 return cast<FunctionDecl>(CallEvent::getDecl());
499 }
500
501 RuntimeDefinition getRuntimeDefinition() const override;
502
503 bool argumentsMayEscape() const override;
504
505 void getInitialStackFrameContents(const StackFrameContext *CalleeCtx,
506 BindingsTy &Bindings) const override;
507
508 ArrayRef<ParmVarDecl *> parameters() const override;
509
510 static bool classof(const CallEvent *CA) {
511 return CA->getKind() >= CE_BEG_FUNCTION_CALLS &&
512 CA->getKind() <= CE_END_FUNCTION_CALLS;
513 }
514};
515
516/// Represents a C function or static C++ member function call.
517///
518/// Example: \c fun()
519class SimpleFunctionCall : public AnyFunctionCall {
520 friend class CallEventManager;
521
522protected:
523 SimpleFunctionCall(const CallExpr *CE, ProgramStateRef St,
524 const LocationContext *LCtx)
525 : AnyFunctionCall(CE, St, LCtx) {}
526 SimpleFunctionCall(const SimpleFunctionCall &Other) = default;
527
528 void cloneTo(void *Dest) const override {
529 new (Dest) SimpleFunctionCall(*this);
530 }
531
532public:
533 const CallExpr *getOriginExpr() const override {
534 return cast<CallExpr>(AnyFunctionCall::getOriginExpr());
535 }
536
537 const FunctionDecl *getDecl() const override;
538
539 unsigned getNumArgs() const override { return getOriginExpr()->getNumArgs(); }
540
541 const Expr *getArgExpr(unsigned Index) const override {
542 return getOriginExpr()->getArg(Index);
543 }
544
545 Kind getKind() const override { return CE_Function; }
546 StringRef getKindAsString() const override { return "SimpleFunctionCall"; }
547
548 static bool classof(const CallEvent *CA) {
549 return CA->getKind() == CE_Function;
550 }
551};
552
553/// Represents a call to a block.
554///
555/// Example: <tt>^{ statement-body }()</tt>
556class BlockCall : public CallEvent {
557 friend class CallEventManager;
558
559protected:
560 BlockCall(const CallExpr *CE, ProgramStateRef St,
561 const LocationContext *LCtx)
562 : CallEvent(CE, St, LCtx) {}
563 BlockCall(const BlockCall &Other) = default;
564
565 void cloneTo(void *Dest) const override { new (Dest) BlockCall(*this); }
566
567 void getExtraInvalidatedValues(ValueList &Values,
568 RegionAndSymbolInvalidationTraits *ETraits) const override;
569
570public:
571 const CallExpr *getOriginExpr() const override {
572 return cast<CallExpr>(CallEvent::getOriginExpr());
573 }
574
575 unsigned getNumArgs() const override { return getOriginExpr()->getNumArgs(); }
576
577 const Expr *getArgExpr(unsigned Index) const override {
578 return getOriginExpr()->getArg(Index);
579 }
580
581 /// Returns the region associated with this instance of the block.
582 ///
583 /// This may be NULL if the block's origin is unknown.
584 const BlockDataRegion *getBlockRegion() const;
585
586 const BlockDecl *getDecl() const override {
587 const BlockDataRegion *BR = getBlockRegion();
588 if (!BR)
589 return nullptr;
590 return BR->getDecl();
591 }
592
593 bool isConversionFromLambda() const {
594 const BlockDecl *BD = getDecl();
595 if (!BD)
596 return false;
597
598 return BD->isConversionFromLambda();
599 }
600
601 /// For a block converted from a C++ lambda, returns the block
602 /// VarRegion for the variable holding the captured C++ lambda record.
603 const VarRegion *getRegionStoringCapturedLambda() const {
604 assert(isConversionFromLambda());
605 const BlockDataRegion *BR = getBlockRegion();
606 assert(BR && "Block converted from lambda must have a block region");
607
608 auto I = BR->referenced_vars_begin();
609 assert(I != BR->referenced_vars_end());
610
611 return I.getCapturedRegion();
612 }
613
614 RuntimeDefinition getRuntimeDefinition() const override {
615 if (!isConversionFromLambda())
616 return RuntimeDefinition(getDecl());
617
618 // Clang converts lambdas to blocks with an implicit user-defined
619 // conversion operator method on the lambda record that looks (roughly)
620 // like:
621 //
622 // typedef R(^block_type)(P1, P2, ...);
623 // operator block_type() const {
624 // auto Lambda = *this;
625 // return ^(P1 p1, P2 p2, ...){
626 // /* return Lambda(p1, p2, ...); */
627 // };
628 // }
629 //
630 // Here R is the return type of the lambda and P1, P2, ... are
631 // its parameter types. 'Lambda' is a fake VarDecl captured by the block
632 // that is initialized to a copy of the lambda.
633 //
634 // Sema leaves the body of a lambda-converted block empty (it is
635 // produced by CodeGen), so we can't analyze it directly. Instead, we skip
636 // the block body and analyze the operator() method on the captured lambda.
637 const VarDecl *LambdaVD = getRegionStoringCapturedLambda()->getDecl();
638 const CXXRecordDecl *LambdaDecl = LambdaVD->getType()->getAsCXXRecordDecl();
639 CXXMethodDecl* LambdaCallOperator = LambdaDecl->getLambdaCallOperator();
640
641 return RuntimeDefinition(LambdaCallOperator);
642 }
643
644 bool argumentsMayEscape() const override {
645 return true;
646 }
647
648 void getInitialStackFrameContents(const StackFrameContext *CalleeCtx,
649 BindingsTy &Bindings) const override;
650
651 ArrayRef<ParmVarDecl *> parameters() const override;
652
653 Kind getKind() const override { return CE_Block; }
654 StringRef getKindAsString() const override { return "BlockCall"; }
655
656 static bool classof(const CallEvent *CA) { return CA->getKind() == CE_Block; }
657};
658
659/// Represents a non-static C++ member function call, no matter how
660/// it is written.
661class CXXInstanceCall : public AnyFunctionCall {
662protected:
663 CXXInstanceCall(const CallExpr *CE, ProgramStateRef St,
664 const LocationContext *LCtx)
665 : AnyFunctionCall(CE, St, LCtx) {}
666 CXXInstanceCall(const FunctionDecl *D, ProgramStateRef St,
667 const LocationContext *LCtx)
668 : AnyFunctionCall(D, St, LCtx) {}
669 CXXInstanceCall(const CXXInstanceCall &Other) = default;
670
671 void getExtraInvalidatedValues(ValueList &Values,
672 RegionAndSymbolInvalidationTraits *ETraits) const override;
673
674public:
675 /// Returns the expression representing the implicit 'this' object.
676 virtual const Expr *getCXXThisExpr() const { return nullptr; }
677
678 /// Returns the value of the implicit 'this' object.
679 virtual SVal getCXXThisVal() const;
680
681 const FunctionDecl *getDecl() const override;
682
683 RuntimeDefinition getRuntimeDefinition() const override;
684
685 void getInitialStackFrameContents(const StackFrameContext *CalleeCtx,
686 BindingsTy &Bindings) const override;
687
688 static bool classof(const CallEvent *CA) {
689 return CA->getKind() >= CE_BEG_CXX_INSTANCE_CALLS &&
690 CA->getKind() <= CE_END_CXX_INSTANCE_CALLS;
691 }
692};
693
694/// Represents a non-static C++ member function call.
695///
696/// Example: \c obj.fun()
697class CXXMemberCall : public CXXInstanceCall {
698 friend class CallEventManager;
699
700protected:
701 CXXMemberCall(const CXXMemberCallExpr *CE, ProgramStateRef St,
702 const LocationContext *LCtx)
703 : CXXInstanceCall(CE, St, LCtx) {}
704 CXXMemberCall(const CXXMemberCall &Other) = default;
705
706 void cloneTo(void *Dest) const override { new (Dest) CXXMemberCall(*this); }
707
708public:
709 const CXXMemberCallExpr *getOriginExpr() const override {
710 return cast<CXXMemberCallExpr>(CXXInstanceCall::getOriginExpr());
711 }
712
713 unsigned getNumArgs() const override {
714 if (const CallExpr *CE = getOriginExpr())
715 return CE->getNumArgs();
716 return 0;
717 }
718
719 const Expr *getArgExpr(unsigned Index) const override {
720 return getOriginExpr()->getArg(Index);
721 }
722
723 const Expr *getCXXThisExpr() const override;
724
725 RuntimeDefinition getRuntimeDefinition() const override;
726
727 Kind getKind() const override { return CE_CXXMember; }
728 StringRef getKindAsString() const override { return "CXXMemberCall"; }
729
730 static bool classof(const CallEvent *CA) {
731 return CA->getKind() == CE_CXXMember;
732 }
733};
734
735/// Represents a C++ overloaded operator call where the operator is
736/// implemented as a non-static member function.
737///
738/// Example: <tt>iter + 1</tt>
739class CXXMemberOperatorCall : public CXXInstanceCall {
740 friend class CallEventManager;
741
742protected:
743 CXXMemberOperatorCall(const CXXOperatorCallExpr *CE, ProgramStateRef St,
744 const LocationContext *LCtx)
745 : CXXInstanceCall(CE, St, LCtx) {}
746 CXXMemberOperatorCall(const CXXMemberOperatorCall &Other) = default;
747
748 void cloneTo(void *Dest) const override {
749 new (Dest) CXXMemberOperatorCall(*this);
750 }
751
752public:
753 const CXXOperatorCallExpr *getOriginExpr() const override {
754 return cast<CXXOperatorCallExpr>(CXXInstanceCall::getOriginExpr());
755 }
756
757 unsigned getNumArgs() const override {
758 return getOriginExpr()->getNumArgs() - 1;
759 }
760
761 const Expr *getArgExpr(unsigned Index) const override {
762 return getOriginExpr()->getArg(Index + 1);
763 }
764
765 const Expr *getCXXThisExpr() const override;
766
767 Kind getKind() const override { return CE_CXXMemberOperator; }
768 StringRef getKindAsString() const override { return "CXXMemberOperatorCall"; }
769
770 static bool classof(const CallEvent *CA) {
771 return CA->getKind() == CE_CXXMemberOperator;
772 }
773
774 Optional<unsigned>
775 getAdjustedParameterIndex(unsigned ASTArgumentIndex) const override {
776 // For member operator calls argument 0 on the expression corresponds
777 // to implicit this-parameter on the declaration.
778 return (ASTArgumentIndex > 0) ? Optional<unsigned>(ASTArgumentIndex - 1)
779 : None;
780 }
781
782 unsigned getASTArgumentIndex(unsigned CallArgumentIndex) const override {
783 // For member operator calls argument 0 on the expression corresponds
784 // to implicit this-parameter on the declaration.
785 return CallArgumentIndex + 1;
786 }
787
788 OverloadedOperatorKind getOverloadedOperator() const {
789 return getOriginExpr()->getOperator();
790 }
791};
792
793/// Represents an implicit call to a C++ destructor.
794///
795/// This can occur at the end of a scope (for automatic objects), at the end
796/// of a full-expression (for temporaries), or as part of a delete.
797class CXXDestructorCall : public CXXInstanceCall {
798 friend class CallEventManager;
799
800protected:
801 using DtorDataTy = llvm::PointerIntPair<const MemRegion *, 1, bool>;
802
803 /// Creates an implicit destructor.
804 ///
805 /// \param DD The destructor that will be called.
806 /// \param Trigger The statement whose completion causes this destructor call.
807 /// \param Target The object region to be destructed.
808 /// \param St The path-sensitive state at this point in the program.
809 /// \param LCtx The location context at this point in the program.
810 CXXDestructorCall(const CXXDestructorDecl *DD, const Stmt *Trigger,
811 const MemRegion *Target, bool IsBaseDestructor,
812 ProgramStateRef St, const LocationContext *LCtx)
813 : CXXInstanceCall(DD, St, LCtx) {
814 Data = DtorDataTy(Target, IsBaseDestructor).getOpaqueValue();
815 Location = Trigger->getEndLoc();
816 }
817
818 CXXDestructorCall(const CXXDestructorCall &Other) = default;
819
820 void cloneTo(void *Dest) const override {new (Dest) CXXDestructorCall(*this);}
821
822public:
823 SourceRange getSourceRange() const override { return Location; }
824 unsigned getNumArgs() const override { return 0; }
825
826 RuntimeDefinition getRuntimeDefinition() const override;
827
828 /// Returns the value of the implicit 'this' object.
829 SVal getCXXThisVal() const override;
830
831 /// Returns true if this is a call to a base class destructor.
832 bool isBaseDestructor() const {
833 return DtorDataTy::getFromOpaqueValue(Data).getInt();
834 }
835
836 Kind getKind() const override { return CE_CXXDestructor; }
837 StringRef getKindAsString() const override { return "CXXDestructorCall"; }
838
839 static bool classof(const CallEvent *CA) {
840 return CA->getKind() == CE_CXXDestructor;
841 }
842};
843
844/// Represents any constructor invocation. This includes regular constructors
845/// and inherited constructors.
846class AnyCXXConstructorCall : public AnyFunctionCall {
847protected:
848 AnyCXXConstructorCall(const Expr *E, const MemRegion *Target,
849 ProgramStateRef St, const LocationContext *LCtx)
850 : AnyFunctionCall(E, St, LCtx) {
851 assert(E && (isa<CXXConstructExpr>(E) || isa<CXXInheritedCtorInitExpr>(E)));
852 // Target may be null when the region is unknown.
853 Data = Target;
854 }
855
856 void getExtraInvalidatedValues(ValueList &Values,
857 RegionAndSymbolInvalidationTraits *ETraits) const override;
858
859 void getInitialStackFrameContents(const StackFrameContext *CalleeCtx,
860 BindingsTy &Bindings) const override;
861
862public:
863 /// Returns the value of the implicit 'this' object.
864 SVal getCXXThisVal() const;
865
866 static bool classof(const CallEvent *Call) {
867 return Call->getKind() >= CE_BEG_CXX_CONSTRUCTOR_CALLS &&
868 Call->getKind() <= CE_END_CXX_CONSTRUCTOR_CALLS;
869 }
870};
871
872/// Represents a call to a C++ constructor.
873///
874/// Example: \c T(1)
875class CXXConstructorCall : public AnyCXXConstructorCall {
876 friend class CallEventManager;
877
878protected:
879 /// Creates a constructor call.
880 ///
881 /// \param CE The constructor expression as written in the source.
882 /// \param Target The region where the object should be constructed. If NULL,
883 /// a new symbolic region will be used.
884 /// \param St The path-sensitive state at this point in the program.
885 /// \param LCtx The location context at this point in the program.
886 CXXConstructorCall(const CXXConstructExpr *CE, const MemRegion *Target,
887 ProgramStateRef St, const LocationContext *LCtx)
888 : AnyCXXConstructorCall(CE, Target, St, LCtx) {}
889
890 CXXConstructorCall(const CXXConstructorCall &Other) = default;
891
892 void cloneTo(void *Dest) const override { new (Dest) CXXConstructorCall(*this); }
893
894public:
895 const CXXConstructExpr *getOriginExpr() const override {
896 return cast<CXXConstructExpr>(AnyFunctionCall::getOriginExpr());
897 }
898
899 const CXXConstructorDecl *getDecl() const override {
900 return getOriginExpr()->getConstructor();
901 }
902
903 unsigned getNumArgs() const override { return getOriginExpr()->getNumArgs(); }
904
905 const Expr *getArgExpr(unsigned Index) const override {
906 return getOriginExpr()->getArg(Index);
907 }
908
909 Kind getKind() const override { return CE_CXXConstructor; }
910 StringRef getKindAsString() const override { return "CXXConstructorCall"; }
911
912 static bool classof(const CallEvent *CA) {
913 return CA->getKind() == CE_CXXConstructor;
914 }
915};
916
917/// Represents a call to a C++ inherited constructor.
918///
919/// Example: \c class T : public S { using S::S; }; T(1);
920///
921// Note, it is difficult to model the parameters. This is one of the reasons
922// why we skip analysis of inheriting constructors as top-level functions.
923// CXXInheritedCtorInitExpr doesn't take arguments and doesn't model parameter
924// initialization because there is none: the arguments in the outer
925// CXXConstructExpr directly initialize the parameters of the base class
926// constructor, and no copies are made. (Making a copy of the parameter is
927// incorrect, at least if it's done in an observable way.) The derived class
928// constructor doesn't even exist in the formal model.
929/// E.g., in:
930///
931/// struct X { X *p = this; ~X() {} };
932/// struct A { A(X x) : b(x.p == &x) {} bool b; };
933/// struct B : A { using A::A; };
934/// B b = X{};
935///
936/// ... b.b is initialized to true.
937class CXXInheritedConstructorCall : public AnyCXXConstructorCall {
938 friend class CallEventManager;
939
940protected:
941 CXXInheritedConstructorCall(const CXXInheritedCtorInitExpr *CE,
942 const MemRegion *Target, ProgramStateRef St,
943 const LocationContext *LCtx)
944 : AnyCXXConstructorCall(CE, Target, St, LCtx) {}
945
946 CXXInheritedConstructorCall(const CXXInheritedConstructorCall &Other) =
947 default;
948
949 void cloneTo(void *Dest) const override {
950 new (Dest) CXXInheritedConstructorCall(*this);
951 }
952
953public:
954 const CXXInheritedCtorInitExpr *getOriginExpr() const override {
955 return cast<CXXInheritedCtorInitExpr>(AnyFunctionCall::getOriginExpr());
956 }
957
958 const CXXConstructorDecl *getDecl() const override {
959 return getOriginExpr()->getConstructor();
960 }
961
962 /// Obtain the stack frame of the inheriting constructor. Argument expressions
963 /// can be found on the call site of that stack frame.
964 const StackFrameContext *getInheritingStackFrame() const;
965
966 /// Obtain the CXXConstructExpr for the sub-class that inherited the current
967 /// constructor (possibly indirectly). It's the statement that contains
968 /// argument expressions.
969 const CXXConstructExpr *getInheritingConstructor() const {
970 return cast<CXXConstructExpr>(getInheritingStackFrame()->getCallSite());
971 }
972
973 unsigned getNumArgs() const override {
974 return getInheritingConstructor()->getNumArgs();
975 }
976
977 const Expr *getArgExpr(unsigned Index) const override {
978 return getInheritingConstructor()->getArg(Index);
979 }
980
981 SVal getArgSVal(unsigned Index) const override {
982 return getState()->getSVal(
983 getArgExpr(Index),
984 getInheritingStackFrame()->getParent()->getStackFrame());
985 }
986
987 Kind getKind() const override { return CE_CXXInheritedConstructor; }
988 StringRef getKindAsString() const override {
989 return "CXXInheritedConstructorCall";
990 }
991
992 static bool classof(const CallEvent *CA) {
993 return CA->getKind() == CE_CXXInheritedConstructor;
994 }
995};
996
997/// Represents the memory allocation call in a C++ new-expression.
998///
999/// This is a call to "operator new".
1000class CXXAllocatorCall : public AnyFunctionCall {
1001 friend class CallEventManager;
1002
1003protected:
1004 CXXAllocatorCall(const CXXNewExpr *E, ProgramStateRef St,
1005 const LocationContext *LCtx)
1006 : AnyFunctionCall(E, St, LCtx) {}
1007 CXXAllocatorCall(const CXXAllocatorCall &Other) = default;
1008
1009 void cloneTo(void *Dest) const override { new (Dest) CXXAllocatorCall(*this); }
1010
1011public:
1012 const CXXNewExpr *getOriginExpr() const override {
1013 return cast<CXXNewExpr>(AnyFunctionCall::getOriginExpr());
1014 }
1015
1016 const FunctionDecl *getDecl() const override {
1017 return getOriginExpr()->getOperatorNew();
1018 }
1019
1020 SVal getObjectUnderConstruction() const {
1021 return ExprEngine::getObjectUnderConstruction(getState(), getOriginExpr(),
1022 getLocationContext())
1023 .getValue();
1024 }
1025
1026 /// Number of non-placement arguments to the call. It is equal to 2 for
1027 /// C++17 aligned operator new() calls that have alignment implicitly
1028 /// passed as the second argument, and to 1 for other operator new() calls.
1029 unsigned getNumImplicitArgs() const {
1030 return getOriginExpr()->passAlignment() ? 2 : 1;
1031 }
1032
1033 unsigned getNumArgs() const override {
1034 return getOriginExpr()->getNumPlacementArgs() + getNumImplicitArgs();
1035 }
1036
1037 const Expr *getArgExpr(unsigned Index) const override {
1038 // The first argument of an allocator call is the size of the allocation.
1039 if (Index < getNumImplicitArgs())
1040 return nullptr;
1041 return getOriginExpr()->getPlacementArg(Index - getNumImplicitArgs());
1042 }
1043
1044 /// Number of placement arguments to the operator new() call. For example,
1045 /// standard std::nothrow operator new and standard placement new both have
1046 /// 1 implicit argument (size) and 1 placement argument, while regular
1047 /// operator new() has 1 implicit argument and 0 placement arguments.
1048 const Expr *getPlacementArgExpr(unsigned Index) const {
1049 return getOriginExpr()->getPlacementArg(Index);
1050 }
1051
1052 Kind getKind() const override { return CE_CXXAllocator; }
1053 StringRef getKindAsString() const override { return "CXXAllocatorCall"; }
1054
1055 static bool classof(const CallEvent *CE) {
1056 return CE->getKind() == CE_CXXAllocator;
1057 }
1058};
1059
1060/// Represents the memory deallocation call in a C++ delete-expression.
1061///
1062/// This is a call to "operator delete".
1063// FIXME: CXXDeleteExpr isn't present for custom delete operators, or even for
1064// some those that are in the standard library, like the no-throw or align_val
1065// versions.
1066// Some pointers:
1067// http://lists.llvm.org/pipermail/cfe-dev/2020-April/065080.html
1068// clang/test/Analysis/cxx-dynamic-memory-analysis-order.cpp
1069// clang/unittests/StaticAnalyzer/CallEventTest.cpp
1070class CXXDeallocatorCall : public AnyFunctionCall {
1071 friend class CallEventManager;
1072
1073protected:
1074 CXXDeallocatorCall(const CXXDeleteExpr *E, ProgramStateRef St,
1075 const LocationContext *LCtx)
1076 : AnyFunctionCall(E, St, LCtx) {}
1077 CXXDeallocatorCall(const CXXDeallocatorCall &Other) = default;
1078
1079 void cloneTo(void *Dest) const override {
1080 new (Dest) CXXDeallocatorCall(*this);
1081 }
1082
1083public:
1084 const CXXDeleteExpr *getOriginExpr() const override {
1085 return cast<CXXDeleteExpr>(AnyFunctionCall::getOriginExpr());
1086 }
1087
1088 const FunctionDecl *getDecl() const override {
1089 return getOriginExpr()->getOperatorDelete();
1090 }
1091
1092 unsigned getNumArgs() const override { return getDecl()->getNumParams(); }
1093
1094 const Expr *getArgExpr(unsigned Index) const override {
1095 // CXXDeleteExpr's only have a single argument.
1096 return getOriginExpr()->getArgument();
1097 }
1098
1099 Kind getKind() const override { return CE_CXXDeallocator; }
1100 StringRef getKindAsString() const override { return "CXXDeallocatorCall"; }
1101
1102 static bool classof(const CallEvent *CE) {
1103 return CE->getKind() == CE_CXXDeallocator;
1104 }
1105};
1106
1107/// Represents the ways an Objective-C message send can occur.
1108//
1109// Note to maintainers: OCM_Message should always be last, since it does not
1110// need to fit in the Data field's low bits.
1111enum ObjCMessageKind {
1112 OCM_PropertyAccess,
1113 OCM_Subscript,
1114 OCM_Message
1115};
1116
1117/// Represents any expression that calls an Objective-C method.
1118///
1119/// This includes all of the kinds listed in ObjCMessageKind.
1120class ObjCMethodCall : public CallEvent {
1121 friend class CallEventManager;
1122
1123 const PseudoObjectExpr *getContainingPseudoObjectExpr() const;
1124
1125protected:
1126 ObjCMethodCall(const ObjCMessageExpr *Msg, ProgramStateRef St,
1127 const LocationContext *LCtx)
1128 : CallEvent(Msg, St, LCtx) {
1129 Data = nullptr;
1130 }
1131
1132 ObjCMethodCall(const ObjCMethodCall &Other) = default;
1133
1134 void cloneTo(void *Dest) const override { new (Dest) ObjCMethodCall(*this); }
1135
1136 void getExtraInvalidatedValues(ValueList &Values,
1137 RegionAndSymbolInvalidationTraits *ETraits) const override;
1138
1139 /// Check if the selector may have multiple definitions (may have overrides).
1140 virtual bool canBeOverridenInSubclass(ObjCInterfaceDecl *IDecl,
1141 Selector Sel) const;
1142
1143public:
1144 const ObjCMessageExpr *getOriginExpr() const override {
1145 return cast<ObjCMessageExpr>(CallEvent::getOriginExpr());
1146 }
1147
1148 const ObjCMethodDecl *getDecl() const override {
1149 return getOriginExpr()->getMethodDecl();
1150 }
1151
1152 unsigned getNumArgs() const override {
1153 return getOriginExpr()->getNumArgs();
1154 }
1155
1156 const Expr *getArgExpr(unsigned Index) const override {
1157 return getOriginExpr()->getArg(Index);
1158 }
1159
1160 bool isInstanceMessage() const {
1161 return getOriginExpr()->isInstanceMessage();
1162 }
1163
1164 ObjCMethodFamily getMethodFamily() const {
1165 return getOriginExpr()->getMethodFamily();
1166 }
1167
1168 Selector getSelector() const {
1169 return getOriginExpr()->getSelector();
1170 }
1171
1172 SourceRange getSourceRange() const override;
1173
1174 /// Returns the value of the receiver at the time of this call.
1175 SVal getReceiverSVal() const;
1176
1177 /// Get the interface for the receiver.
1178 ///
1179 /// This works whether this is an instance message or a class message.
1180 /// However, it currently just uses the static type of the receiver.
1181 const ObjCInterfaceDecl *getReceiverInterface() const {
1182 return getOriginExpr()->getReceiverInterface();
1183 }
1184
1185 /// Checks if the receiver refers to 'self' or 'super'.
1186 bool isReceiverSelfOrSuper() const;
1187
1188 /// Returns how the message was written in the source (property access,
1189 /// subscript, or explicit message send).
1190 ObjCMessageKind getMessageKind() const;
1191
1192 /// Returns true if this property access or subscript is a setter (has the
1193 /// form of an assignment).
1194 bool isSetter() const {
1195 switch (getMessageKind()) {
1196 case OCM_Message:
1197 llvm_unreachable("This is not a pseudo-object access!");
1198 case OCM_PropertyAccess:
1199 return getNumArgs() > 0;
1200 case OCM_Subscript:
1201 return getNumArgs() > 1;
1202 }
1203 llvm_unreachable("Unknown message kind");
1204 }
1205
1206 // Returns the property accessed by this method, either explicitly via
1207 // property syntax or implicitly via a getter or setter method. Returns
1208 // nullptr if the call is not a prooperty access.
1209 const ObjCPropertyDecl *getAccessedProperty() const;
1210
1211 RuntimeDefinition getRuntimeDefinition() const override;
1212
1213 bool argumentsMayEscape() const override;
1214
1215 void getInitialStackFrameContents(const StackFrameContext *CalleeCtx,
1216 BindingsTy &Bindings) const override;
1217
1218 ArrayRef<ParmVarDecl*> parameters() const override;
1219
1220 Kind getKind() const override { return CE_ObjCMessage; }
1221 StringRef getKindAsString() const override { return "ObjCMethodCall"; }
1222
1223 static bool classof(const CallEvent *CA) {
1224 return CA->getKind() == CE_ObjCMessage;
1225 }
1226};
1227
1228enum CallDescriptionFlags : int {
1229 /// Describes a C standard function that is sometimes implemented as a macro
1230 /// that expands to a compiler builtin with some __builtin prefix.
1231 /// The builtin may as well have a few extra arguments on top of the requested
1232 /// number of arguments.
1233 CDF_MaybeBuiltin = 1 << 0,
1234};
1235
1236/// This class represents a description of a function call using the number of
1237/// arguments and the name of the function.
1238class CallDescription {
1239 friend CallEvent;
1240
1241 mutable IdentifierInfo *II = nullptr;
1242 mutable bool IsLookupDone = false;
1243 // The list of the qualified names used to identify the specified CallEvent,
1244 // e.g. "{a, b}" represent the qualified names, like "a::b".
1245 std::vector<const char *> QualifiedName;
1246 Optional<unsigned> RequiredArgs;
1247 Optional<size_t> RequiredParams;
1248 int Flags;
1249
1250 // A constructor helper.
1251 static Optional<size_t> readRequiredParams(Optional<unsigned> RequiredArgs,
1252 Optional<size_t> RequiredParams) {
1253 if (RequiredParams)
1254 return RequiredParams;
1255 if (RequiredArgs)
1256 return static_cast<size_t>(*RequiredArgs);
1257 return None;
1258 }
1259
1260public:
1261 /// Constructs a CallDescription object.
1262 ///
1263 /// @param QualifiedName The list of the name qualifiers of the function that
1264 /// will be matched. The user is allowed to skip any of the qualifiers.
1265 /// For example, {"std", "basic_string", "c_str"} would match both
1266 /// std::basic_string<...>::c_str() and std::__1::basic_string<...>::c_str().
1267 ///
1268 /// @param RequiredArgs The number of arguments that is expected to match a
1269 /// call. Omit this parameter to match every occurrence of call with a given
1270 /// name regardless the number of arguments.
1271 CallDescription(int Flags, ArrayRef<const char *> QualifiedName,
1272 Optional<unsigned> RequiredArgs = None,
1273 Optional<size_t> RequiredParams = None)
1274 : QualifiedName(QualifiedName), RequiredArgs(RequiredArgs),
1275 RequiredParams(readRequiredParams(RequiredArgs, RequiredParams)),
1276 Flags(Flags) {}
1277
1278 /// Construct a CallDescription with default flags.
1279 CallDescription(ArrayRef<const char *> QualifiedName,
1280 Optional<unsigned> RequiredArgs = None,
1281 Optional<size_t> RequiredParams = None)
1282 : CallDescription(0, QualifiedName, RequiredArgs, RequiredParams) {}
1283
1284 /// Get the name of the function that this object matches.
1285 StringRef getFunctionName() const { return QualifiedName.back(); }
1286};
1287
1288/// An immutable map from CallDescriptions to arbitrary data. Provides a unified
1289/// way for checkers to react on function calls.
1290template <typename T> class CallDescriptionMap {
1291 // Some call descriptions aren't easily hashable (eg., the ones with qualified
1292 // names in which some sections are omitted), so let's put them
1293 // in a simple vector and use linear lookup.
1294 // TODO: Implement an actual map for fast lookup for "hashable" call
1295 // descriptions (eg., the ones for C functions that just match the name).
1296 std::vector<std::pair<CallDescription, T>> LinearMap;
1297
1298public:
1299 CallDescriptionMap(
1300 std::initializer_list<std::pair<CallDescription, T>> &&List)
1301 : LinearMap(List) {}
1302
1303 ~CallDescriptionMap() = default;
1304
1305 // These maps are usually stored once per checker, so let's make sure
1306 // we don't do redundant copies.
1307 CallDescriptionMap(const CallDescriptionMap &) = delete;
1308 CallDescriptionMap &operator=(const CallDescription &) = delete;
1309
1310 const T *lookup(const CallEvent &Call) const {
1311 // Slow path: linear lookup.
1312 // TODO: Implement some sort of fast path.
1313 for (const std::pair<CallDescription, T> &I : LinearMap)
1314 if (Call.isCalled(I.first))
1315 return &I.second;
1316
1317 return nullptr;
1318 }
1319};
1320
1321/// Manages the lifetime of CallEvent objects.
1322///
1323/// CallEventManager provides a way to create arbitrary CallEvents "on the
1324/// stack" as if they were value objects by keeping a cache of CallEvent-sized
1325/// memory blocks. The CallEvents created by CallEventManager are only valid
1326/// for the lifetime of the OwnedCallEvent that holds them; right now these
1327/// objects cannot be copied and ownership cannot be transferred.
1328class CallEventManager {
1329 friend class CallEvent;
1330
1331 llvm::BumpPtrAllocator &Alloc;
1332 SmallVector<void *, 8> Cache;
1333
1334 using CallEventTemplateTy = SimpleFunctionCall;
1335
1336 void reclaim(const void *Memory) {
1337 Cache.push_back(const_cast<void *>(Memory));
1338 }
1339
1340 /// Returns memory that can be initialized as a CallEvent.
1341 void *allocate() {
1342 if (Cache.empty())
1343 return Alloc.Allocate<CallEventTemplateTy>();
1344 else
1345 return Cache.pop_back_val();
1346 }
1347
1348 template <typename T, typename Arg>
1349 T *create(Arg A, ProgramStateRef St, const LocationContext *LCtx) {
1350 static_assert(sizeof(T) == sizeof(CallEventTemplateTy),
1351 "CallEvent subclasses are not all the same size");
1352 return new (allocate()) T(A, St, LCtx);
1353 }
1354
1355 template <typename T, typename Arg1, typename Arg2>
1356 T *create(Arg1 A1, Arg2 A2, ProgramStateRef St, const LocationContext *LCtx) {
1357 static_assert(sizeof(T) == sizeof(CallEventTemplateTy),
1358 "CallEvent subclasses are not all the same size");
1359 return new (allocate()) T(A1, A2, St, LCtx);
1360 }
1361
1362 template <typename T, typename Arg1, typename Arg2, typename Arg3>
1363 T *create(Arg1 A1, Arg2 A2, Arg3 A3, ProgramStateRef St,
1364 const LocationContext *LCtx) {
1365 static_assert(sizeof(T) == sizeof(CallEventTemplateTy),
1366 "CallEvent subclasses are not all the same size");
1367 return new (allocate()) T(A1, A2, A3, St, LCtx);
1368 }
1369
1370 template <typename T, typename Arg1, typename Arg2, typename Arg3,
1371 typename Arg4>
1372 T *create(Arg1 A1, Arg2 A2, Arg3 A3, Arg4 A4, ProgramStateRef St,
1373 const LocationContext *LCtx) {
1374 static_assert(sizeof(T) == sizeof(CallEventTemplateTy),
1375 "CallEvent subclasses are not all the same size");
1376 return new (allocate()) T(A1, A2, A3, A4, St, LCtx);
1377 }
1378
1379public:
1380 CallEventManager(llvm::BumpPtrAllocator &alloc) : Alloc(alloc) {}
1381
1382 /// Gets an outside caller given a callee context.
1383 CallEventRef<>
1384 getCaller(const StackFrameContext *CalleeCtx, ProgramStateRef State);
1385
1386 /// Gets a call event for a function call, Objective-C method call,
1387 /// or a 'new' call.
1388 CallEventRef<>
1389 getCall(const Stmt *S, ProgramStateRef State,
1390 const LocationContext *LC);
1391
1392 CallEventRef<>
1393 getSimpleCall(const CallExpr *E, ProgramStateRef State,
1394 const LocationContext *LCtx);
1395
1396 CallEventRef<ObjCMethodCall>
1397 getObjCMethodCall(const ObjCMessageExpr *E, ProgramStateRef State,
1398 const LocationContext *LCtx) {
1399 return create<ObjCMethodCall>(E, State, LCtx);
1400 }
1401
1402 CallEventRef<CXXConstructorCall>
1403 getCXXConstructorCall(const CXXConstructExpr *E, const MemRegion *Target,
1404 ProgramStateRef State, const LocationContext *LCtx) {
1405 return create<CXXConstructorCall>(E, Target, State, LCtx);
1406 }
1407
1408 CallEventRef<CXXInheritedConstructorCall>
1409 getCXXInheritedConstructorCall(const CXXInheritedCtorInitExpr *E,
1410 const MemRegion *Target, ProgramStateRef State,
1411 const LocationContext *LCtx) {
1412 return create<CXXInheritedConstructorCall>(E, Target, State, LCtx);
1413 }
1414
1415 CallEventRef<CXXDestructorCall>
1416 getCXXDestructorCall(const CXXDestructorDecl *DD, const Stmt *Trigger,
1417 const MemRegion *Target, bool IsBase,
1418 ProgramStateRef State, const LocationContext *LCtx) {
1419 return create<CXXDestructorCall>(DD, Trigger, Target, IsBase, State, LCtx);
1420 }
1421
1422 CallEventRef<CXXAllocatorCall>
1423 getCXXAllocatorCall(const CXXNewExpr *E, ProgramStateRef State,
1424 const LocationContext *LCtx) {
1425 return create<CXXAllocatorCall>(E, State, LCtx);
1426 }
1427
1428 CallEventRef<CXXDeallocatorCall>
1429 getCXXDeallocatorCall(const CXXDeleteExpr *E, ProgramStateRef State,
1430 const LocationContext *LCtx) {
1431 return create<CXXDeallocatorCall>(E, State, LCtx);
1432 }
1433};
1434
1435template <typename T>
1436CallEventRef<T> CallEvent::cloneWithState(ProgramStateRef NewState) const {
1437 assert(isa<T>(*this) && "Cloning to unrelated type");
1438 static_assert(sizeof(T) == sizeof(CallEvent),
1439 "Subclasses may not add fields");
1440
1441 if (NewState == State)
1442 return cast<T>(this);
1443
1444 CallEventManager &Mgr = State->getStateManager().getCallEventManager();
1445 T *Copy = static_cast<T *>(Mgr.allocate());
1446 cloneTo(Copy);
1447 assert(Copy->getKind() == this->getKind() && "Bad copy");
1448
1449 Copy->State = NewState;
1450 return Copy;
1451}
1452
1453inline void CallEvent::Release() const {
1454 assert(RefCount > 0 && "Reference count is already zero.");
1455 --RefCount;
1456
1457 if (RefCount > 0)
1458 return;
1459
1460 CallEventManager &Mgr = State->getStateManager().getCallEventManager();
1461 Mgr.reclaim(this);
1462
1463 this->~CallEvent();
1464}
1465
1466} // namespace ento
1467
1468} // namespace clang
1469
1470namespace llvm {
1471
1472// Support isa<>, cast<>, and dyn_cast<> for CallEventRef.
1473template<class T> struct simplify_type< clang::ento::CallEventRef<T>> {
1474 using SimpleType = const T *;
1475
1476 static SimpleType
1477 getSimplifiedValue(clang::ento::CallEventRef<T> Val) {
1478 return Val.get();
1479 }
1480};
1481
1482} // namespace llvm
1483
1484#endif // LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_CALLEVENT_H
1485