1//===- CallEvent.h - Wrapper for all function and method calls ----*- C++ -*--// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10/// \file This file defines CallEvent and its subclasses, which represent path- 11/// sensitive instances of different kinds of function and method calls 12/// (C, C++, and Objective-C). 13// 14//===----------------------------------------------------------------------===// 15 16#ifndef LLVM_CLANG_STATICANALYZER_PATHSENSITIVE_CALL 17#define LLVM_CLANG_STATICANALYZER_PATHSENSITIVE_CALL 18 19#include "clang/AST/DeclCXX.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/AST/ExprObjC.h" 22#include "clang/Analysis/AnalysisContext.h" 23#include "clang/Basic/SourceManager.h" 24#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h" 25#include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h" 26#include "llvm/ADT/PointerIntPair.h" 27 28namespace clang { 29class ProgramPoint; 30class ProgramPointTag; 31 32namespace ento { 33 34enum CallEventKind { 35 CE_Function, 36 CE_Block, 37 CE_BEG_SIMPLE_CALLS = CE_Function, 38 CE_END_SIMPLE_CALLS = CE_Block, 39 CE_CXXMember, 40 CE_CXXMemberOperator, 41 CE_CXXDestructor, 42 CE_BEG_CXX_INSTANCE_CALLS = CE_CXXMember, 43 CE_END_CXX_INSTANCE_CALLS = CE_CXXDestructor, 44 CE_CXXConstructor, 45 CE_CXXAllocator, 46 CE_BEG_FUNCTION_CALLS = CE_Function, 47 CE_END_FUNCTION_CALLS = CE_CXXAllocator, 48 CE_ObjCMessage 49}; 50 51class CallEvent; 52class CallEventManager; 53 54template<typename T = CallEvent> 55class CallEventRef : public IntrusiveRefCntPtr<const T> { 56public: 57 CallEventRef(const T *Call) : IntrusiveRefCntPtr<const T>(Call) {} 58 CallEventRef(const CallEventRef &Orig) : IntrusiveRefCntPtr<const T>(Orig) {} 59 60 CallEventRef<T> cloneWithState(ProgramStateRef State) const { 61 return this->getPtr()->template cloneWithState<T>(State); 62 } 63 64 // Allow implicit conversions to a superclass type, since CallEventRef 65 // behaves like a pointer-to-const. 66 template <typename SuperT> 67 operator CallEventRef<SuperT> () const { 68 return this->getPtr(); 69 } 70}; 71 72/// \class RuntimeDefinition 73/// \brief Defines the runtime definition of the called function. 74/// 75/// Encapsulates the information we have about which Decl will be used 76/// when the call is executed on the given path. When dealing with dynamic 77/// dispatch, the information is based on DynamicTypeInfo and might not be 78/// precise. 79class RuntimeDefinition { 80 /// The Declaration of the function which could be called at runtime. 81 /// NULL if not available. 82 const Decl *D; 83 84 /// The region representing an object (ObjC/C++) on which the method is 85 /// called. With dynamic dispatch, the method definition depends on the 86 /// runtime type of this object. NULL when the DynamicTypeInfo is 87 /// precise. 88 const MemRegion *R; 89 90public: 91 RuntimeDefinition(): D(0), R(0) {} 92 RuntimeDefinition(const Decl *InD): D(InD), R(0) {} 93 RuntimeDefinition(const Decl *InD, const MemRegion *InR): D(InD), R(InR) {} 94 const Decl *getDecl() { return D; } 95 96 /// \brief Check if the definition we have is precise. 97 /// If not, it is possible that the call dispatches to another definition at 98 /// execution time. 99 bool mayHaveOtherDefinitions() { return R != 0; } 100 101 /// When other definitions are possible, returns the region whose runtime type 102 /// determines the method definition. 103 const MemRegion *getDispatchRegion() { return R; } 104}; 105 106/// \brief Represents an abstract call to a function or method along a 107/// particular path. 108/// 109/// CallEvents are created through the factory methods of CallEventManager. 110/// 111/// CallEvents should always be cheap to create and destroy. In order for 112/// CallEventManager to be able to re-use CallEvent-sized memory blocks, 113/// subclasses of CallEvent may not add any data members to the base class. 114/// Use the "Data" and "Location" fields instead. 115class CallEvent { 116public: 117 typedef CallEventKind Kind; 118 119private: 120 ProgramStateRef State; 121 const LocationContext *LCtx; 122 llvm::PointerUnion<const Expr *, const Decl *> Origin; 123 124 void operator=(const CallEvent &) LLVM_DELETED_FUNCTION; 125 126protected: 127 // This is user data for subclasses. 128 const void *Data; 129 130 // This is user data for subclasses. 131 // This should come right before RefCount, so that the two fields can be 132 // packed together on LP64 platforms. 133 SourceLocation Location; 134 135private: 136 mutable unsigned RefCount; 137 138 template <typename T> friend struct llvm::IntrusiveRefCntPtrInfo; 139 void Retain() const { ++RefCount; } 140 void Release() const; 141 142protected: 143 friend class CallEventManager; 144 145 CallEvent(const Expr *E, ProgramStateRef state, const LocationContext *lctx) 146 : State(state), LCtx(lctx), Origin(E), RefCount(0) {} 147 148 CallEvent(const Decl *D, ProgramStateRef state, const LocationContext *lctx) 149 : State(state), LCtx(lctx), Origin(D), RefCount(0) {} 150 151 // DO NOT MAKE PUBLIC 152 CallEvent(const CallEvent &Original) 153 : State(Original.State), LCtx(Original.LCtx), Origin(Original.Origin), 154 Data(Original.Data), Location(Original.Location), RefCount(0) {} 155 156 /// Copies this CallEvent, with vtable intact, into a new block of memory. 157 virtual void cloneTo(void *Dest) const = 0; 158 159 /// \brief Get the value of arbitrary expressions at this point in the path. 160 SVal getSVal(const Stmt *S) const { 161 return getState()->getSVal(S, getLocationContext()); 162 } 163 164 165 typedef SmallVectorImpl<SVal> ValueList; 166 167 /// \brief Used to specify non-argument regions that will be invalidated as a 168 /// result of this call. 169 virtual void getExtraInvalidatedValues(ValueList &Values) const {} 170 171public: 172 virtual ~CallEvent() {} 173 174 /// \brief Returns the kind of call this is. 175 virtual Kind getKind() const = 0; 176 177 /// \brief Returns the declaration of the function or method that will be 178 /// called. May be null. 179 virtual const Decl *getDecl() const { 180 return Origin.dyn_cast<const Decl *>(); 181 } 182 183 /// \brief The state in which the call is being evaluated. 184 const ProgramStateRef &getState() const { 185 return State; 186 } 187 188 /// \brief The context in which the call is being evaluated. 189 const LocationContext *getLocationContext() const { 190 return LCtx; 191 } 192 193 /// \brief Returns the definition of the function or method that will be 194 /// called. 195 virtual RuntimeDefinition getRuntimeDefinition() const = 0; 196 197 /// \brief Returns the expression whose value will be the result of this call. 198 /// May be null. 199 const Expr *getOriginExpr() const { 200 return Origin.dyn_cast<const Expr *>(); 201 } 202 203 /// \brief Returns the number of arguments (explicit and implicit). 204 /// 205 /// Note that this may be greater than the number of parameters in the 206 /// callee's declaration, and that it may include arguments not written in 207 /// the source. 208 virtual unsigned getNumArgs() const = 0; 209 210 /// \brief Returns true if the callee is known to be from a system header. 211 bool isInSystemHeader() const { 212 const Decl *D = getDecl(); 213 if (!D) 214 return false; 215 216 SourceLocation Loc = D->getLocation(); 217 if (Loc.isValid()) { 218 const SourceManager &SM = 219 getState()->getStateManager().getContext().getSourceManager(); 220 return SM.isInSystemHeader(D->getLocation()); 221 } 222 223 // Special case for implicitly-declared global operator new/delete. 224 // These should be considered system functions. 225 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) 226 return FD->isOverloadedOperator() && FD->isImplicit() && FD->isGlobal(); 227 228 return false; 229 } 230 231 /// \brief Returns true if this is a call to a variadic function or method. 232 virtual bool isVariadic() const { 233 return false; 234 } 235 236 /// \brief Returns a source range for the entire call, suitable for 237 /// outputting in diagnostics. 238 virtual SourceRange getSourceRange() const { 239 return getOriginExpr()->getSourceRange(); 240 } 241 242 /// \brief Returns the value of a given argument at the time of the call. 243 virtual SVal getArgSVal(unsigned Index) const; 244 245 /// \brief Returns the expression associated with a given argument. 246 /// May be null if this expression does not appear in the source. 247 virtual const Expr *getArgExpr(unsigned Index) const { return 0; } 248 249 /// \brief Returns the source range for errors associated with this argument. 250 /// 251 /// May be invalid if the argument is not written in the source. 252 virtual SourceRange getArgSourceRange(unsigned Index) const; 253 254 /// \brief Returns the result type, adjusted for references. 255 QualType getResultType() const; 256 257 /// \brief Returns the return value of the call. 258 /// 259 /// This should only be called if the CallEvent was created using a state in 260 /// which the return value has already been bound to the origin expression. 261 SVal getReturnValue() const; 262 263 /// \brief Returns true if any of the arguments appear to represent callbacks. 264 bool hasNonZeroCallbackArg() const; 265 266 /// \brief Returns true if any of the arguments are known to escape to long- 267 /// term storage, even if this method will not modify them. 268 // NOTE: The exact semantics of this are still being defined! 269 // We don't really want a list of hardcoded exceptions in the long run, 270 // but we don't want duplicated lists of known APIs in the short term either. 271 virtual bool argumentsMayEscape() const { 272 return hasNonZeroCallbackArg(); 273 } 274 275 /// \brief Returns true if the callee is an externally-visible function in the 276 /// top-level namespace, such as \c malloc. 277 /// 278 /// You can use this call to determine that a particular function really is 279 /// a library function and not, say, a C++ member function with the same name. 280 /// 281 /// If a name is provided, the function must additionally match the given 282 /// name. 283 /// 284 /// Note that this deliberately excludes C++ library functions in the \c std 285 /// namespace, but will include C library functions accessed through the 286 /// \c std namespace. This also does not check if the function is declared 287 /// as 'extern "C"', or if it uses C++ name mangling. 288 // FIXME: Add a helper for checking namespaces. 289 // FIXME: Move this down to AnyFunctionCall once checkers have more 290 // precise callbacks. 291 bool isGlobalCFunction(StringRef SpecificName = StringRef()) const; 292 293 /// \brief Returns the name of the callee, if its name is a simple identifier. 294 /// 295 /// Note that this will fail for Objective-C methods, blocks, and C++ 296 /// overloaded operators. The former is named by a Selector rather than a 297 /// simple identifier, and the latter two do not have names. 298 // FIXME: Move this down to AnyFunctionCall once checkers have more 299 // precise callbacks. 300 const IdentifierInfo *getCalleeIdentifier() const { 301 const NamedDecl *ND = dyn_cast_or_null<NamedDecl>(getDecl()); 302 if (!ND) 303 return 0; 304 return ND->getIdentifier(); 305 } 306 307 /// \brief Returns an appropriate ProgramPoint for this call. 308 ProgramPoint getProgramPoint(bool IsPreVisit = false, 309 const ProgramPointTag *Tag = 0) const; 310 311 /// \brief Returns a new state with all argument regions invalidated. 312 /// 313 /// This accepts an alternate state in case some processing has already 314 /// occurred. 315 ProgramStateRef invalidateRegions(unsigned BlockCount, 316 ProgramStateRef Orig = 0) const; 317 318 typedef std::pair<Loc, SVal> FrameBindingTy; 319 typedef SmallVectorImpl<FrameBindingTy> BindingsTy; 320 321 /// Populates the given SmallVector with the bindings in the callee's stack 322 /// frame at the start of this call. 323 virtual void getInitialStackFrameContents(const StackFrameContext *CalleeCtx, 324 BindingsTy &Bindings) const = 0; 325 326 /// Returns a copy of this CallEvent, but using the given state. 327 template <typename T> 328 CallEventRef<T> cloneWithState(ProgramStateRef NewState) const; 329 330 /// Returns a copy of this CallEvent, but using the given state. 331 CallEventRef<> cloneWithState(ProgramStateRef NewState) const { 332 return cloneWithState<CallEvent>(NewState); 333 } 334 335 /// \brief Returns true if this is a statement is a function or method call 336 /// of some kind. 337 static bool isCallStmt(const Stmt *S); 338 339 /// \brief Returns the result type of a function or method declaration. 340 /// 341 /// This will return a null QualType if the result type cannot be determined. 342 static QualType getDeclaredResultType(const Decl *D); 343 344 // Iterator access to formal parameters and their types. 345private: 346 typedef std::const_mem_fun_t<QualType, ParmVarDecl> get_type_fun; 347 348public: 349 typedef const ParmVarDecl * const *param_iterator; 350 351 /// Returns an iterator over the call's formal parameters. 352 /// 353 /// Remember that the number of formal parameters may not match the number 354 /// of arguments for all calls. However, the first parameter will always 355 /// correspond with the argument value returned by \c getArgSVal(0). 356 /// 357 /// If the call has no accessible declaration, \c param_begin() will be equal 358 /// to \c param_end(). 359 virtual param_iterator param_begin() const = 0; 360 /// \sa param_begin() 361 virtual param_iterator param_end() const = 0; 362 363 typedef llvm::mapped_iterator<param_iterator, get_type_fun> 364 param_type_iterator; 365 366 /// Returns an iterator over the types of the call's formal parameters. 367 /// 368 /// This uses the callee decl found by default name lookup rather than the 369 /// definition because it represents a public interface, and probably has 370 /// more annotations. 371 param_type_iterator param_type_begin() const { 372 return llvm::map_iterator(param_begin(), 373 get_type_fun(&ParmVarDecl::getType)); 374 } 375 /// \sa param_type_begin() 376 param_type_iterator param_type_end() const { 377 return llvm::map_iterator(param_end(), get_type_fun(&ParmVarDecl::getType)); 378 } 379 380 // For debugging purposes only 381 void dump(raw_ostream &Out) const; 382 LLVM_ATTRIBUTE_USED void dump() const; 383}; 384 385 386/// \brief Represents a call to any sort of function that might have a 387/// FunctionDecl. 388class AnyFunctionCall : public CallEvent { 389protected: 390 AnyFunctionCall(const Expr *E, ProgramStateRef St, 391 const LocationContext *LCtx) 392 : CallEvent(E, St, LCtx) {} 393 AnyFunctionCall(const Decl *D, ProgramStateRef St, 394 const LocationContext *LCtx) 395 : CallEvent(D, St, LCtx) {} 396 AnyFunctionCall(const AnyFunctionCall &Other) : CallEvent(Other) {} 397 398public: 399 // This function is overridden by subclasses, but they must return 400 // a FunctionDecl. 401 virtual const FunctionDecl *getDecl() const { 402 return cast<FunctionDecl>(CallEvent::getDecl()); 403 } 404 405 virtual RuntimeDefinition getRuntimeDefinition() const { 406 const FunctionDecl *FD = getDecl(); 407 // Note that the AnalysisDeclContext will have the FunctionDecl with 408 // the definition (if one exists). 409 if (FD) { 410 AnalysisDeclContext *AD = 411 getLocationContext()->getAnalysisDeclContext()-> 412 getManager()->getContext(FD); 413 if (AD->getBody()) 414 return RuntimeDefinition(AD->getDecl()); 415 } 416 417 return RuntimeDefinition(); 418 } 419 420 virtual bool isVariadic() const { 421 return getDecl()->isVariadic(); 422 } 423 424 virtual bool argumentsMayEscape() const; 425 426 virtual void getInitialStackFrameContents(const StackFrameContext *CalleeCtx, 427 BindingsTy &Bindings) const; 428 429 virtual param_iterator param_begin() const; 430 virtual param_iterator param_end() const; 431 432 static bool classof(const CallEvent *CA) { 433 return CA->getKind() >= CE_BEG_FUNCTION_CALLS && 434 CA->getKind() <= CE_END_FUNCTION_CALLS; 435 } 436}; 437 438/// \brief Represents a call to a non-C++ function, written as a CallExpr. 439class SimpleCall : public AnyFunctionCall { 440protected: 441 SimpleCall(const CallExpr *CE, ProgramStateRef St, 442 const LocationContext *LCtx) 443 : AnyFunctionCall(CE, St, LCtx) {} 444 SimpleCall(const SimpleCall &Other) : AnyFunctionCall(Other) {} 445 446public: 447 virtual const CallExpr *getOriginExpr() const { 448 return cast<CallExpr>(AnyFunctionCall::getOriginExpr()); 449 } 450 451 virtual const FunctionDecl *getDecl() const; 452 453 virtual unsigned getNumArgs() const { return getOriginExpr()->getNumArgs(); } 454 455 virtual const Expr *getArgExpr(unsigned Index) const { 456 return getOriginExpr()->getArg(Index); 457 } 458 459 static bool classof(const CallEvent *CA) { 460 return CA->getKind() >= CE_BEG_SIMPLE_CALLS && 461 CA->getKind() <= CE_END_SIMPLE_CALLS; 462 } 463}; 464 465/// \brief Represents a C function or static C++ member function call. 466/// 467/// Example: \c fun() 468class FunctionCall : public SimpleCall { 469 friend class CallEventManager; 470 471protected: 472 FunctionCall(const CallExpr *CE, ProgramStateRef St, 473 const LocationContext *LCtx) 474 : SimpleCall(CE, St, LCtx) {} 475 476 FunctionCall(const FunctionCall &Other) : SimpleCall(Other) {} 477 virtual void cloneTo(void *Dest) const { new (Dest) FunctionCall(*this); } 478 479public: 480 virtual Kind getKind() const { return CE_Function; } 481 482 static bool classof(const CallEvent *CA) { 483 return CA->getKind() == CE_Function; 484 } 485}; 486 487/// \brief Represents a call to a block. 488/// 489/// Example: <tt>^{ /* ... */ }()</tt> 490class BlockCall : public SimpleCall { 491 friend class CallEventManager; 492 493protected: 494 BlockCall(const CallExpr *CE, ProgramStateRef St, 495 const LocationContext *LCtx) 496 : SimpleCall(CE, St, LCtx) {} 497 498 BlockCall(const BlockCall &Other) : SimpleCall(Other) {} 499 virtual void cloneTo(void *Dest) const { new (Dest) BlockCall(*this); } 500 501 virtual void getExtraInvalidatedValues(ValueList &Values) const; 502 503public: 504 /// \brief Returns the region associated with this instance of the block. 505 /// 506 /// This may be NULL if the block's origin is unknown. 507 const BlockDataRegion *getBlockRegion() const; 508 509 /// \brief Gets the declaration of the block. 510 /// 511 /// This is not an override of getDecl() because AnyFunctionCall has already 512 /// assumed that it's a FunctionDecl. 513 const BlockDecl *getBlockDecl() const { 514 const BlockDataRegion *BR = getBlockRegion(); 515 if (!BR) 516 return 0; 517 return BR->getDecl(); 518 } 519 520 virtual RuntimeDefinition getRuntimeDefinition() const { 521 return RuntimeDefinition(getBlockDecl()); 522 } 523 524 virtual bool isVariadic() const { 525 return getBlockDecl()->isVariadic(); 526 } 527 528 virtual void getInitialStackFrameContents(const StackFrameContext *CalleeCtx, 529 BindingsTy &Bindings) const; 530 531 virtual param_iterator param_begin() const; 532 virtual param_iterator param_end() const; 533 534 virtual Kind getKind() const { return CE_Block; } 535 536 static bool classof(const CallEvent *CA) { 537 return CA->getKind() == CE_Block; 538 } 539}; 540 541/// \brief Represents a non-static C++ member function call, no matter how 542/// it is written. 543class CXXInstanceCall : public AnyFunctionCall { 544protected: 545 virtual void getExtraInvalidatedValues(ValueList &Values) const; 546 547 CXXInstanceCall(const CallExpr *CE, ProgramStateRef St, 548 const LocationContext *LCtx) 549 : AnyFunctionCall(CE, St, LCtx) {} 550 CXXInstanceCall(const FunctionDecl *D, ProgramStateRef St, 551 const LocationContext *LCtx) 552 : AnyFunctionCall(D, St, LCtx) {} 553 554 555 CXXInstanceCall(const CXXInstanceCall &Other) : AnyFunctionCall(Other) {} 556 557public: 558 /// \brief Returns the expression representing the implicit 'this' object. 559 virtual const Expr *getCXXThisExpr() const { return 0; } 560 561 /// \brief Returns the value of the implicit 'this' object. 562 virtual SVal getCXXThisVal() const; 563 564 virtual const FunctionDecl *getDecl() const; 565 566 virtual RuntimeDefinition getRuntimeDefinition() const; 567 568 virtual void getInitialStackFrameContents(const StackFrameContext *CalleeCtx, 569 BindingsTy &Bindings) const; 570 571 static bool classof(const CallEvent *CA) { 572 return CA->getKind() >= CE_BEG_CXX_INSTANCE_CALLS && 573 CA->getKind() <= CE_END_CXX_INSTANCE_CALLS; 574 } 575}; 576 577/// \brief Represents a non-static C++ member function call. 578/// 579/// Example: \c obj.fun() 580class CXXMemberCall : public CXXInstanceCall { 581 friend class CallEventManager; 582 583protected: 584 CXXMemberCall(const CXXMemberCallExpr *CE, ProgramStateRef St, 585 const LocationContext *LCtx) 586 : CXXInstanceCall(CE, St, LCtx) {} 587 588 CXXMemberCall(const CXXMemberCall &Other) : CXXInstanceCall(Other) {} 589 virtual void cloneTo(void *Dest) const { new (Dest) CXXMemberCall(*this); } 590 591public: 592 virtual const CXXMemberCallExpr *getOriginExpr() const { 593 return cast<CXXMemberCallExpr>(CXXInstanceCall::getOriginExpr()); 594 } 595 596 virtual unsigned getNumArgs() const { 597 if (const CallExpr *CE = getOriginExpr()) 598 return CE->getNumArgs(); 599 return 0; 600 } 601 602 virtual const Expr *getArgExpr(unsigned Index) const { 603 return getOriginExpr()->getArg(Index); 604 } 605 606 virtual const Expr *getCXXThisExpr() const; 607 608 virtual RuntimeDefinition getRuntimeDefinition() const; 609 610 virtual Kind getKind() const { return CE_CXXMember; } 611 612 static bool classof(const CallEvent *CA) { 613 return CA->getKind() == CE_CXXMember; 614 } 615}; 616 617/// \brief Represents a C++ overloaded operator call where the operator is 618/// implemented as a non-static member function. 619/// 620/// Example: <tt>iter + 1</tt> 621class CXXMemberOperatorCall : public CXXInstanceCall { 622 friend class CallEventManager; 623 624protected: 625 CXXMemberOperatorCall(const CXXOperatorCallExpr *CE, ProgramStateRef St, 626 const LocationContext *LCtx) 627 : CXXInstanceCall(CE, St, LCtx) {} 628 629 CXXMemberOperatorCall(const CXXMemberOperatorCall &Other) 630 : CXXInstanceCall(Other) {} 631 virtual void cloneTo(void *Dest) const { 632 new (Dest) CXXMemberOperatorCall(*this); 633 } 634 635public: 636 virtual const CXXOperatorCallExpr *getOriginExpr() const { 637 return cast<CXXOperatorCallExpr>(CXXInstanceCall::getOriginExpr()); 638 } 639 640 virtual unsigned getNumArgs() const { 641 return getOriginExpr()->getNumArgs() - 1; 642 } 643 virtual const Expr *getArgExpr(unsigned Index) const { 644 return getOriginExpr()->getArg(Index + 1); 645 } 646 647 virtual const Expr *getCXXThisExpr() const; 648 649 virtual Kind getKind() const { return CE_CXXMemberOperator; } 650 651 static bool classof(const CallEvent *CA) { 652 return CA->getKind() == CE_CXXMemberOperator; 653 } 654}; 655 656/// \brief Represents an implicit call to a C++ destructor. 657/// 658/// This can occur at the end of a scope (for automatic objects), at the end 659/// of a full-expression (for temporaries), or as part of a delete. 660class CXXDestructorCall : public CXXInstanceCall { 661 friend class CallEventManager; 662 663protected: 664 typedef llvm::PointerIntPair<const MemRegion *, 1, bool> DtorDataTy; 665 666 /// Creates an implicit destructor. 667 /// 668 /// \param DD The destructor that will be called. 669 /// \param Trigger The statement whose completion causes this destructor call. 670 /// \param Target The object region to be destructed. 671 /// \param St The path-sensitive state at this point in the program. 672 /// \param LCtx The location context at this point in the program. 673 CXXDestructorCall(const CXXDestructorDecl *DD, const Stmt *Trigger, 674 const MemRegion *Target, bool IsBaseDestructor, 675 ProgramStateRef St, const LocationContext *LCtx) 676 : CXXInstanceCall(DD, St, LCtx) { 677 Data = DtorDataTy(Target, IsBaseDestructor).getOpaqueValue(); 678 Location = Trigger->getLocEnd(); 679 } 680 681 CXXDestructorCall(const CXXDestructorCall &Other) : CXXInstanceCall(Other) {} 682 virtual void cloneTo(void *Dest) const { new (Dest) CXXDestructorCall(*this); } 683 684public: 685 virtual SourceRange getSourceRange() const { return Location; } 686 virtual unsigned getNumArgs() const { return 0; } 687 688 virtual RuntimeDefinition getRuntimeDefinition() const; 689 690 /// \brief Returns the value of the implicit 'this' object. 691 virtual SVal getCXXThisVal() const; 692 693 /// Returns true if this is a call to a base class destructor. 694 bool isBaseDestructor() const { 695 return DtorDataTy::getFromOpaqueValue(Data).getInt(); 696 } 697 698 virtual Kind getKind() const { return CE_CXXDestructor; } 699 700 static bool classof(const CallEvent *CA) { 701 return CA->getKind() == CE_CXXDestructor; 702 } 703}; 704 705/// \brief Represents a call to a C++ constructor. 706/// 707/// Example: \c T(1) 708class CXXConstructorCall : public AnyFunctionCall { 709 friend class CallEventManager; 710 711protected: 712 /// Creates a constructor call. 713 /// 714 /// \param CE The constructor expression as written in the source. 715 /// \param Target The region where the object should be constructed. If NULL, 716 /// a new symbolic region will be used. 717 /// \param St The path-sensitive state at this point in the program. 718 /// \param LCtx The location context at this point in the program. 719 CXXConstructorCall(const CXXConstructExpr *CE, const MemRegion *Target, 720 ProgramStateRef St, const LocationContext *LCtx) 721 : AnyFunctionCall(CE, St, LCtx) { 722 Data = Target; 723 } 724 725 CXXConstructorCall(const CXXConstructorCall &Other) : AnyFunctionCall(Other){} 726 virtual void cloneTo(void *Dest) const { new (Dest) CXXConstructorCall(*this); } 727 728 virtual void getExtraInvalidatedValues(ValueList &Values) const; 729 730public: 731 virtual const CXXConstructExpr *getOriginExpr() const { 732 return cast<CXXConstructExpr>(AnyFunctionCall::getOriginExpr()); 733 } 734 735 virtual const CXXConstructorDecl *getDecl() const { 736 return getOriginExpr()->getConstructor(); 737 } 738 739 virtual unsigned getNumArgs() const { return getOriginExpr()->getNumArgs(); } 740 741 virtual const Expr *getArgExpr(unsigned Index) const { 742 return getOriginExpr()->getArg(Index); 743 } 744 745 /// \brief Returns the value of the implicit 'this' object. 746 SVal getCXXThisVal() const; 747 748 virtual void getInitialStackFrameContents(const StackFrameContext *CalleeCtx, 749 BindingsTy &Bindings) const; 750 751 virtual Kind getKind() const { return CE_CXXConstructor; } 752 753 static bool classof(const CallEvent *CA) { 754 return CA->getKind() == CE_CXXConstructor; 755 } 756}; 757 758/// \brief Represents the memory allocation call in a C++ new-expression. 759/// 760/// This is a call to "operator new". 761class CXXAllocatorCall : public AnyFunctionCall { 762 friend class CallEventManager; 763 764protected: 765 CXXAllocatorCall(const CXXNewExpr *E, ProgramStateRef St, 766 const LocationContext *LCtx) 767 : AnyFunctionCall(E, St, LCtx) {} 768 769 CXXAllocatorCall(const CXXAllocatorCall &Other) : AnyFunctionCall(Other) {} 770 virtual void cloneTo(void *Dest) const { new (Dest) CXXAllocatorCall(*this); } 771 772public: 773 virtual const CXXNewExpr *getOriginExpr() const { 774 return cast<CXXNewExpr>(AnyFunctionCall::getOriginExpr()); 775 } 776 777 virtual const FunctionDecl *getDecl() const { 778 return getOriginExpr()->getOperatorNew(); 779 } 780 781 virtual unsigned getNumArgs() const { 782 return getOriginExpr()->getNumPlacementArgs() + 1; 783 } 784 785 virtual const Expr *getArgExpr(unsigned Index) const { 786 // The first argument of an allocator call is the size of the allocation. 787 if (Index == 0) 788 return 0; 789 return getOriginExpr()->getPlacementArg(Index - 1); 790 } 791 792 virtual Kind getKind() const { return CE_CXXAllocator; } 793 794 static bool classof(const CallEvent *CE) { 795 return CE->getKind() == CE_CXXAllocator; 796 } 797}; 798 799/// \brief Represents the ways an Objective-C message send can occur. 800// 801// Note to maintainers: OCM_Message should always be last, since it does not 802// need to fit in the Data field's low bits. 803enum ObjCMessageKind { 804 OCM_PropertyAccess, 805 OCM_Subscript, 806 OCM_Message 807}; 808 809/// \brief Represents any expression that calls an Objective-C method. 810/// 811/// This includes all of the kinds listed in ObjCMessageKind. 812class ObjCMethodCall : public CallEvent { 813 friend class CallEventManager; 814 815 const PseudoObjectExpr *getContainingPseudoObjectExpr() const; 816 817protected: 818 ObjCMethodCall(const ObjCMessageExpr *Msg, ProgramStateRef St, 819 const LocationContext *LCtx) 820 : CallEvent(Msg, St, LCtx) { 821 Data = 0; 822 } 823 824 ObjCMethodCall(const ObjCMethodCall &Other) : CallEvent(Other) {} 825 virtual void cloneTo(void *Dest) const { new (Dest) ObjCMethodCall(*this); } 826 827 virtual void getExtraInvalidatedValues(ValueList &Values) const; 828 829 /// Check if the selector may have multiple definitions (may have overrides). 830 virtual bool canBeOverridenInSubclass(ObjCInterfaceDecl *IDecl, 831 Selector Sel) const; 832 833public: 834 virtual const ObjCMessageExpr *getOriginExpr() const { 835 return cast<ObjCMessageExpr>(CallEvent::getOriginExpr()); 836 } 837 virtual const ObjCMethodDecl *getDecl() const { 838 return getOriginExpr()->getMethodDecl(); 839 } 840 virtual unsigned getNumArgs() const { 841 return getOriginExpr()->getNumArgs(); 842 } 843 virtual const Expr *getArgExpr(unsigned Index) const { 844 return getOriginExpr()->getArg(Index); 845 } 846 virtual bool isVariadic() const { 847 return getDecl()->isVariadic(); 848 } 849 850 bool isInstanceMessage() const { 851 return getOriginExpr()->isInstanceMessage(); 852 } 853 ObjCMethodFamily getMethodFamily() const { 854 return getOriginExpr()->getMethodFamily(); 855 } 856 Selector getSelector() const { 857 return getOriginExpr()->getSelector(); 858 } 859 860 virtual SourceRange getSourceRange() const; 861 862 /// \brief Returns the value of the receiver at the time of this call. 863 SVal getReceiverSVal() const; 864 865 /// \brief Return the value of 'self' if available. 866 SVal getSelfSVal() const; 867 868 /// \brief Get the interface for the receiver. 869 /// 870 /// This works whether this is an instance message or a class message. 871 /// However, it currently just uses the static type of the receiver. 872 const ObjCInterfaceDecl *getReceiverInterface() const { 873 return getOriginExpr()->getReceiverInterface(); 874 } 875 876 /// \brief Checks if the receiver refers to 'self' or 'super'. 877 bool isReceiverSelfOrSuper() const; 878 879 /// Returns how the message was written in the source (property access, 880 /// subscript, or explicit message send). 881 ObjCMessageKind getMessageKind() const; 882 883 /// Returns true if this property access or subscript is a setter (has the 884 /// form of an assignment). 885 bool isSetter() const { 886 switch (getMessageKind()) { 887 case OCM_Message: 888 llvm_unreachable("This is not a pseudo-object access!"); 889 case OCM_PropertyAccess: 890 return getNumArgs() > 0; 891 case OCM_Subscript: 892 return getNumArgs() > 1; 893 } 894 llvm_unreachable("Unknown message kind"); 895 } 896 897 virtual RuntimeDefinition getRuntimeDefinition() const; 898 899 virtual void getInitialStackFrameContents(const StackFrameContext *CalleeCtx, 900 BindingsTy &Bindings) const; 901 902 virtual param_iterator param_begin() const; 903 virtual param_iterator param_end() const; 904 905 virtual Kind getKind() const { return CE_ObjCMessage; } 906 907 static bool classof(const CallEvent *CA) { 908 return CA->getKind() == CE_ObjCMessage; 909 } 910}; 911 912 913/// \brief Manages the lifetime of CallEvent objects. 914/// 915/// CallEventManager provides a way to create arbitrary CallEvents "on the 916/// stack" as if they were value objects by keeping a cache of CallEvent-sized 917/// memory blocks. The CallEvents created by CallEventManager are only valid 918/// for the lifetime of the OwnedCallEvent that holds them; right now these 919/// objects cannot be copied and ownership cannot be transferred. 920class CallEventManager { 921 friend class CallEvent; 922 923 llvm::BumpPtrAllocator &Alloc; 924 SmallVector<void *, 8> Cache; 925 926 void reclaim(const void *Memory) { 927 Cache.push_back(const_cast<void *>(Memory)); 928 } 929 930 /// Returns memory that can be initialized as a CallEvent. 931 void *allocate() { 932 if (Cache.empty()) 933 return Alloc.Allocate<FunctionCall>(); 934 else 935 return Cache.pop_back_val(); 936 } 937 938 template <typename T, typename Arg> 939 T *create(Arg A, ProgramStateRef St, const LocationContext *LCtx) { 940 return new (allocate()) T(A, St, LCtx); 941 } 942 943 template <typename T, typename Arg1, typename Arg2> 944 T *create(Arg1 A1, Arg2 A2, ProgramStateRef St, const LocationContext *LCtx) { 945 return new (allocate()) T(A1, A2, St, LCtx); 946 } 947 948 template <typename T, typename Arg1, typename Arg2, typename Arg3> 949 T *create(Arg1 A1, Arg2 A2, Arg3 A3, ProgramStateRef St, 950 const LocationContext *LCtx) { 951 return new (allocate()) T(A1, A2, A3, St, LCtx); 952 } 953 954 template <typename T, typename Arg1, typename Arg2, typename Arg3, 955 typename Arg4> 956 T *create(Arg1 A1, Arg2 A2, Arg3 A3, Arg4 A4, ProgramStateRef St, 957 const LocationContext *LCtx) { 958 return new (allocate()) T(A1, A2, A3, A4, St, LCtx); 959 } 960 961public: 962 CallEventManager(llvm::BumpPtrAllocator &alloc) : Alloc(alloc) {} 963 964 965 CallEventRef<> 966 getCaller(const StackFrameContext *CalleeCtx, ProgramStateRef State); 967 968 969 CallEventRef<> 970 getSimpleCall(const CallExpr *E, ProgramStateRef State, 971 const LocationContext *LCtx); 972 973 CallEventRef<ObjCMethodCall> 974 getObjCMethodCall(const ObjCMessageExpr *E, ProgramStateRef State, 975 const LocationContext *LCtx) { 976 return create<ObjCMethodCall>(E, State, LCtx); 977 } 978 979 CallEventRef<CXXConstructorCall> 980 getCXXConstructorCall(const CXXConstructExpr *E, const MemRegion *Target, 981 ProgramStateRef State, const LocationContext *LCtx) { 982 return create<CXXConstructorCall>(E, Target, State, LCtx); 983 } 984 985 CallEventRef<CXXDestructorCall> 986 getCXXDestructorCall(const CXXDestructorDecl *DD, const Stmt *Trigger, 987 const MemRegion *Target, bool IsBase, 988 ProgramStateRef State, const LocationContext *LCtx) { 989 return create<CXXDestructorCall>(DD, Trigger, Target, IsBase, State, LCtx); 990 } 991 992 CallEventRef<CXXAllocatorCall> 993 getCXXAllocatorCall(const CXXNewExpr *E, ProgramStateRef State, 994 const LocationContext *LCtx) { 995 return create<CXXAllocatorCall>(E, State, LCtx); 996 } 997}; 998 999 1000template <typename T> 1001CallEventRef<T> CallEvent::cloneWithState(ProgramStateRef NewState) const { 1002 assert(isa<T>(*this) && "Cloning to unrelated type"); 1003 assert(sizeof(T) == sizeof(CallEvent) && "Subclasses may not add fields"); 1004 1005 if (NewState == State) 1006 return cast<T>(this); 1007 1008 CallEventManager &Mgr = State->getStateManager().getCallEventManager(); 1009 T *Copy = static_cast<T *>(Mgr.allocate()); 1010 cloneTo(Copy); 1011 assert(Copy->getKind() == this->getKind() && "Bad copy"); 1012 1013 Copy->State = NewState; 1014 return Copy; 1015} 1016 1017inline void CallEvent::Release() const { 1018 assert(RefCount > 0 && "Reference count is already zero."); 1019 --RefCount; 1020 1021 if (RefCount > 0) 1022 return; 1023 1024 CallEventManager &Mgr = State->getStateManager().getCallEventManager(); 1025 Mgr.reclaim(this); 1026 1027 this->~CallEvent(); 1028} 1029 1030} // end namespace ento 1031} // end namespace clang 1032 1033namespace llvm { 1034 // Support isa<>, cast<>, and dyn_cast<> for CallEventRef. 1035 template<class T> struct simplify_type< clang::ento::CallEventRef<T> > { 1036 typedef const T *SimpleType; 1037 1038 static SimpleType 1039 getSimplifiedValue(clang::ento::CallEventRef<T> Val) { 1040 return Val.getPtr(); 1041 } 1042 }; 1043} 1044 1045#endif 1046