Home | History | Annotate | Download | only in PathSensitive
      1 //===-- ExprEngine.h - Path-Sensitive Expression-Level Dataflow ---*- C++ -*-=//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is distributed under the University of Illinois Open Source
      6 // License. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 //
     10 //  This file defines a meta-engine for path-sensitive dataflow analysis that
     11 //  is built on CoreEngine, but provides the boilerplate to execute transfer
     12 //  functions and build the ExplodedGraph at the expression level.
     13 //
     14 //===----------------------------------------------------------------------===//
     15 
     16 #ifndef LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_EXPRENGINE_H
     17 #define LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_EXPRENGINE_H
     18 
     19 #include "clang/AST/Expr.h"
     20 #include "clang/AST/Type.h"
     21 #include "clang/Analysis/DomainSpecific/ObjCNoReturn.h"
     22 #include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
     23 #include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
     24 #include "clang/StaticAnalyzer/Core/PathSensitive/CoreEngine.h"
     25 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
     26 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h"
     27 #include "clang/StaticAnalyzer/Core/PathSensitive/SubEngine.h"
     28 
     29 namespace clang {
     30 
     31 class AnalysisDeclContextManager;
     32 class CXXCatchStmt;
     33 class CXXConstructExpr;
     34 class CXXDeleteExpr;
     35 class CXXNewExpr;
     36 class CXXTemporaryObjectExpr;
     37 class CXXThisExpr;
     38 class MaterializeTemporaryExpr;
     39 class ObjCAtSynchronizedStmt;
     40 class ObjCForCollectionStmt;
     41 
     42 namespace ento {
     43 
     44 class AnalysisManager;
     45 class CallEvent;
     46 class CXXConstructorCall;
     47 
     48 class ExprEngine : public SubEngine {
     49 public:
     50   /// The modes of inlining, which override the default analysis-wide settings.
     51   enum InliningModes {
     52     /// Follow the default settings for inlining callees.
     53     Inline_Regular = 0,
     54     /// Do minimal inlining of callees.
     55     Inline_Minimal = 0x1
     56   };
     57 
     58 private:
     59   AnalysisManager &AMgr;
     60 
     61   AnalysisDeclContextManager &AnalysisDeclContexts;
     62 
     63   CoreEngine Engine;
     64 
     65   /// G - the simulation graph.
     66   ExplodedGraph& G;
     67 
     68   /// StateMgr - Object that manages the data for all created states.
     69   ProgramStateManager StateMgr;
     70 
     71   /// SymMgr - Object that manages the symbol information.
     72   SymbolManager& SymMgr;
     73 
     74   /// svalBuilder - SValBuilder object that creates SVals from expressions.
     75   SValBuilder &svalBuilder;
     76 
     77   unsigned int currStmtIdx;
     78   const NodeBuilderContext *currBldrCtx;
     79 
     80   /// Helper object to determine if an Objective-C message expression
     81   /// implicitly never returns.
     82   ObjCNoReturn ObjCNoRet;
     83 
     84   /// Whether or not GC is enabled in this analysis.
     85   bool ObjCGCEnabled;
     86 
     87   /// The BugReporter associated with this engine.  It is important that
     88   ///  this object be placed at the very end of member variables so that its
     89   ///  destructor is called before the rest of the ExprEngine is destroyed.
     90   GRBugReporter BR;
     91 
     92   /// The functions which have been analyzed through inlining. This is owned by
     93   /// AnalysisConsumer. It can be null.
     94   SetOfConstDecls *VisitedCallees;
     95 
     96   /// The flag, which specifies the mode of inlining for the engine.
     97   InliningModes HowToInline;
     98 
     99 public:
    100   ExprEngine(AnalysisManager &mgr, bool gcEnabled,
    101              SetOfConstDecls *VisitedCalleesIn,
    102              FunctionSummariesTy *FS,
    103              InliningModes HowToInlineIn);
    104 
    105   ~ExprEngine() override;
    106 
    107   /// Returns true if there is still simulation state on the worklist.
    108   bool ExecuteWorkList(const LocationContext *L, unsigned Steps = 150000) {
    109     return Engine.ExecuteWorkList(L, Steps, nullptr);
    110   }
    111 
    112   /// Execute the work list with an initial state. Nodes that reaches the exit
    113   /// of the function are added into the Dst set, which represent the exit
    114   /// state of the function call. Returns true if there is still simulation
    115   /// state on the worklist.
    116   bool ExecuteWorkListWithInitialState(const LocationContext *L, unsigned Steps,
    117                                        ProgramStateRef InitState,
    118                                        ExplodedNodeSet &Dst) {
    119     return Engine.ExecuteWorkListWithInitialState(L, Steps, InitState, Dst);
    120   }
    121 
    122   /// getContext - Return the ASTContext associated with this analysis.
    123   ASTContext &getContext() const { return AMgr.getASTContext(); }
    124 
    125   AnalysisManager &getAnalysisManager() override { return AMgr; }
    126 
    127   CheckerManager &getCheckerManager() const {
    128     return *AMgr.getCheckerManager();
    129   }
    130 
    131   SValBuilder &getSValBuilder() { return svalBuilder; }
    132 
    133   BugReporter& getBugReporter() { return BR; }
    134 
    135   const NodeBuilderContext &getBuilderContext() {
    136     assert(currBldrCtx);
    137     return *currBldrCtx;
    138   }
    139 
    140   bool isObjCGCEnabled() { return ObjCGCEnabled; }
    141 
    142   const Stmt *getStmt() const;
    143 
    144   void GenerateAutoTransition(ExplodedNode *N);
    145   void enqueueEndOfPath(ExplodedNodeSet &S);
    146   void GenerateCallExitNode(ExplodedNode *N);
    147 
    148   /// Visualize the ExplodedGraph created by executing the simulation.
    149   void ViewGraph(bool trim = false);
    150 
    151   /// Visualize a trimmed ExplodedGraph that only contains paths to the given
    152   /// nodes.
    153   void ViewGraph(ArrayRef<const ExplodedNode*> Nodes);
    154 
    155   /// getInitialState - Return the initial state used for the root vertex
    156   ///  in the ExplodedGraph.
    157   ProgramStateRef getInitialState(const LocationContext *InitLoc) override;
    158 
    159   ExplodedGraph& getGraph() { return G; }
    160   const ExplodedGraph& getGraph() const { return G; }
    161 
    162   /// \brief Run the analyzer's garbage collection - remove dead symbols and
    163   /// bindings from the state.
    164   ///
    165   /// Checkers can participate in this process with two callbacks:
    166   /// \c checkLiveSymbols and \c checkDeadSymbols. See the CheckerDocumentation
    167   /// class for more information.
    168   ///
    169   /// \param Node The predecessor node, from which the processing should start.
    170   /// \param Out The returned set of output nodes.
    171   /// \param ReferenceStmt The statement which is about to be processed.
    172   ///        Everything needed for this statement should be considered live.
    173   ///        A null statement means that everything in child LocationContexts
    174   ///        is dead.
    175   /// \param LC The location context of the \p ReferenceStmt. A null location
    176   ///        context means that we have reached the end of analysis and that
    177   ///        all statements and local variables should be considered dead.
    178   /// \param DiagnosticStmt Used as a location for any warnings that should
    179   ///        occur while removing the dead (e.g. leaks). By default, the
    180   ///        \p ReferenceStmt is used.
    181   /// \param K Denotes whether this is a pre- or post-statement purge. This
    182   ///        must only be ProgramPoint::PostStmtPurgeDeadSymbolsKind if an
    183   ///        entire location context is being cleared, in which case the
    184   ///        \p ReferenceStmt must either be a ReturnStmt or \c NULL. Otherwise,
    185   ///        it must be ProgramPoint::PreStmtPurgeDeadSymbolsKind (the default)
    186   ///        and \p ReferenceStmt must be valid (non-null).
    187   void removeDead(ExplodedNode *Node, ExplodedNodeSet &Out,
    188             const Stmt *ReferenceStmt, const LocationContext *LC,
    189             const Stmt *DiagnosticStmt = nullptr,
    190             ProgramPoint::Kind K = ProgramPoint::PreStmtPurgeDeadSymbolsKind);
    191 
    192   /// processCFGElement - Called by CoreEngine. Used to generate new successor
    193   ///  nodes by processing the 'effects' of a CFG element.
    194   void processCFGElement(const CFGElement E, ExplodedNode *Pred,
    195                          unsigned StmtIdx, NodeBuilderContext *Ctx) override;
    196 
    197   void ProcessStmt(const CFGStmt S, ExplodedNode *Pred);
    198 
    199   void ProcessInitializer(const CFGInitializer I, ExplodedNode *Pred);
    200 
    201   void ProcessImplicitDtor(const CFGImplicitDtor D, ExplodedNode *Pred);
    202 
    203   void ProcessNewAllocator(const CXXNewExpr *NE, ExplodedNode *Pred);
    204 
    205   void ProcessAutomaticObjDtor(const CFGAutomaticObjDtor D,
    206                                ExplodedNode *Pred, ExplodedNodeSet &Dst);
    207   void ProcessDeleteDtor(const CFGDeleteDtor D,
    208                          ExplodedNode *Pred, ExplodedNodeSet &Dst);
    209   void ProcessBaseDtor(const CFGBaseDtor D,
    210                        ExplodedNode *Pred, ExplodedNodeSet &Dst);
    211   void ProcessMemberDtor(const CFGMemberDtor D,
    212                          ExplodedNode *Pred, ExplodedNodeSet &Dst);
    213   void ProcessTemporaryDtor(const CFGTemporaryDtor D,
    214                             ExplodedNode *Pred, ExplodedNodeSet &Dst);
    215 
    216   /// Called by CoreEngine when processing the entrance of a CFGBlock.
    217   void processCFGBlockEntrance(const BlockEdge &L,
    218                                NodeBuilderWithSinks &nodeBuilder,
    219                                ExplodedNode *Pred) override;
    220 
    221   /// ProcessBranch - Called by CoreEngine.  Used to generate successor
    222   ///  nodes by processing the 'effects' of a branch condition.
    223   void processBranch(const Stmt *Condition, const Stmt *Term,
    224                      NodeBuilderContext& BuilderCtx,
    225                      ExplodedNode *Pred,
    226                      ExplodedNodeSet &Dst,
    227                      const CFGBlock *DstT,
    228                      const CFGBlock *DstF) override;
    229 
    230   /// Called by CoreEngine.
    231   /// Used to generate successor nodes for temporary destructors depending
    232   /// on whether the corresponding constructor was visited.
    233   void processCleanupTemporaryBranch(const CXXBindTemporaryExpr *BTE,
    234                                      NodeBuilderContext &BldCtx,
    235                                      ExplodedNode *Pred, ExplodedNodeSet &Dst,
    236                                      const CFGBlock *DstT,
    237                                      const CFGBlock *DstF) override;
    238 
    239   /// Called by CoreEngine.  Used to processing branching behavior
    240   /// at static initializers.
    241   void processStaticInitializer(const DeclStmt *DS,
    242                                 NodeBuilderContext& BuilderCtx,
    243                                 ExplodedNode *Pred,
    244                                 ExplodedNodeSet &Dst,
    245                                 const CFGBlock *DstT,
    246                                 const CFGBlock *DstF) override;
    247 
    248   /// processIndirectGoto - Called by CoreEngine.  Used to generate successor
    249   ///  nodes by processing the 'effects' of a computed goto jump.
    250   void processIndirectGoto(IndirectGotoNodeBuilder& builder) override;
    251 
    252   /// ProcessSwitch - Called by CoreEngine.  Used to generate successor
    253   ///  nodes by processing the 'effects' of a switch statement.
    254   void processSwitch(SwitchNodeBuilder& builder) override;
    255 
    256   /// Called by CoreEngine.  Used to notify checkers that processing a
    257   /// function has begun. Called for both inlined and and top-level functions.
    258   void processBeginOfFunction(NodeBuilderContext &BC,
    259                               ExplodedNode *Pred, ExplodedNodeSet &Dst,
    260                               const BlockEdge &L) override;
    261 
    262   /// Called by CoreEngine.  Used to notify checkers that processing a
    263   /// function has ended. Called for both inlined and and top-level functions.
    264   void processEndOfFunction(NodeBuilderContext& BC,
    265                             ExplodedNode *Pred,
    266                             const ReturnStmt *RS = nullptr) override;
    267 
    268   /// Remove dead bindings/symbols before exiting a function.
    269   void removeDeadOnEndOfFunction(NodeBuilderContext& BC,
    270                                  ExplodedNode *Pred,
    271                                  ExplodedNodeSet &Dst);
    272 
    273   /// Generate the entry node of the callee.
    274   void processCallEnter(NodeBuilderContext& BC, CallEnter CE,
    275                         ExplodedNode *Pred) override;
    276 
    277   /// Generate the sequence of nodes that simulate the call exit and the post
    278   /// visit for CallExpr.
    279   void processCallExit(ExplodedNode *Pred) override;
    280 
    281   /// Called by CoreEngine when the analysis worklist has terminated.
    282   void processEndWorklist(bool hasWorkRemaining) override;
    283 
    284   /// evalAssume - Callback function invoked by the ConstraintManager when
    285   ///  making assumptions about state values.
    286   ProgramStateRef processAssume(ProgramStateRef state, SVal cond,
    287                                 bool assumption) override;
    288 
    289   /// processRegionChanges - Called by ProgramStateManager whenever a change is made
    290   ///  to the store. Used to update checkers that track region values.
    291   ProgramStateRef
    292   processRegionChanges(ProgramStateRef state,
    293                        const InvalidatedSymbols *invalidated,
    294                        ArrayRef<const MemRegion *> ExplicitRegions,
    295                        ArrayRef<const MemRegion *> Regions,
    296                        const LocationContext *LCtx,
    297                        const CallEvent *Call) override;
    298 
    299   /// printState - Called by ProgramStateManager to print checker-specific data.
    300   void printState(raw_ostream &Out, ProgramStateRef State,
    301                   const char *NL, const char *Sep) override;
    302 
    303   ProgramStateManager& getStateManager() override { return StateMgr; }
    304 
    305   StoreManager& getStoreManager() { return StateMgr.getStoreManager(); }
    306 
    307   ConstraintManager& getConstraintManager() {
    308     return StateMgr.getConstraintManager();
    309   }
    310 
    311   // FIXME: Remove when we migrate over to just using SValBuilder.
    312   BasicValueFactory& getBasicVals() {
    313     return StateMgr.getBasicVals();
    314   }
    315 
    316   // FIXME: Remove when we migrate over to just using ValueManager.
    317   SymbolManager& getSymbolManager() { return SymMgr; }
    318   const SymbolManager& getSymbolManager() const { return SymMgr; }
    319 
    320   // Functions for external checking of whether we have unfinished work
    321   bool wasBlocksExhausted() const { return Engine.wasBlocksExhausted(); }
    322   bool hasEmptyWorkList() const { return !Engine.getWorkList()->hasWork(); }
    323   bool hasWorkRemaining() const { return Engine.hasWorkRemaining(); }
    324 
    325   const CoreEngine &getCoreEngine() const { return Engine; }
    326 
    327 public:
    328   /// Visit - Transfer function logic for all statements.  Dispatches to
    329   ///  other functions that handle specific kinds of statements.
    330   void Visit(const Stmt *S, ExplodedNode *Pred, ExplodedNodeSet &Dst);
    331 
    332   /// VisitArraySubscriptExpr - Transfer function for array accesses.
    333   void VisitLvalArraySubscriptExpr(const ArraySubscriptExpr *Ex,
    334                                    ExplodedNode *Pred,
    335                                    ExplodedNodeSet &Dst);
    336 
    337   /// VisitGCCAsmStmt - Transfer function logic for inline asm.
    338   void VisitGCCAsmStmt(const GCCAsmStmt *A, ExplodedNode *Pred,
    339                        ExplodedNodeSet &Dst);
    340 
    341   /// VisitMSAsmStmt - Transfer function logic for MS inline asm.
    342   void VisitMSAsmStmt(const MSAsmStmt *A, ExplodedNode *Pred,
    343                       ExplodedNodeSet &Dst);
    344 
    345   /// VisitBlockExpr - Transfer function logic for BlockExprs.
    346   void VisitBlockExpr(const BlockExpr *BE, ExplodedNode *Pred,
    347                       ExplodedNodeSet &Dst);
    348 
    349   /// VisitLambdaExpr - Transfer function logic for LambdaExprs.
    350   void VisitLambdaExpr(const LambdaExpr *LE, ExplodedNode *Pred,
    351                        ExplodedNodeSet &Dst);
    352 
    353   /// VisitBinaryOperator - Transfer function logic for binary operators.
    354   void VisitBinaryOperator(const BinaryOperator* B, ExplodedNode *Pred,
    355                            ExplodedNodeSet &Dst);
    356 
    357 
    358   /// VisitCall - Transfer function for function calls.
    359   void VisitCallExpr(const CallExpr *CE, ExplodedNode *Pred,
    360                      ExplodedNodeSet &Dst);
    361 
    362   /// VisitCast - Transfer function logic for all casts (implicit and explicit).
    363   void VisitCast(const CastExpr *CastE, const Expr *Ex, ExplodedNode *Pred,
    364                 ExplodedNodeSet &Dst);
    365 
    366   /// VisitCompoundLiteralExpr - Transfer function logic for compound literals.
    367   void VisitCompoundLiteralExpr(const CompoundLiteralExpr *CL,
    368                                 ExplodedNode *Pred, ExplodedNodeSet &Dst);
    369 
    370   /// Transfer function logic for DeclRefExprs and BlockDeclRefExprs.
    371   void VisitCommonDeclRefExpr(const Expr *DR, const NamedDecl *D,
    372                               ExplodedNode *Pred, ExplodedNodeSet &Dst);
    373 
    374   /// VisitDeclStmt - Transfer function logic for DeclStmts.
    375   void VisitDeclStmt(const DeclStmt *DS, ExplodedNode *Pred,
    376                      ExplodedNodeSet &Dst);
    377 
    378   /// VisitGuardedExpr - Transfer function logic for ?, __builtin_choose
    379   void VisitGuardedExpr(const Expr *Ex, const Expr *L, const Expr *R,
    380                         ExplodedNode *Pred, ExplodedNodeSet &Dst);
    381 
    382   void VisitInitListExpr(const InitListExpr *E, ExplodedNode *Pred,
    383                          ExplodedNodeSet &Dst);
    384 
    385   /// VisitLogicalExpr - Transfer function logic for '&&', '||'
    386   void VisitLogicalExpr(const BinaryOperator* B, ExplodedNode *Pred,
    387                         ExplodedNodeSet &Dst);
    388 
    389   /// VisitMemberExpr - Transfer function for member expressions.
    390   void VisitMemberExpr(const MemberExpr *M, ExplodedNode *Pred,
    391                            ExplodedNodeSet &Dst);
    392 
    393   /// VisitMemberExpr - Transfer function for builtin atomic expressions
    394   void VisitAtomicExpr(const AtomicExpr *E, ExplodedNode *Pred,
    395                        ExplodedNodeSet &Dst);
    396 
    397   /// Transfer function logic for ObjCAtSynchronizedStmts.
    398   void VisitObjCAtSynchronizedStmt(const ObjCAtSynchronizedStmt *S,
    399                                    ExplodedNode *Pred, ExplodedNodeSet &Dst);
    400 
    401   /// Transfer function logic for computing the lvalue of an Objective-C ivar.
    402   void VisitLvalObjCIvarRefExpr(const ObjCIvarRefExpr *DR, ExplodedNode *Pred,
    403                                 ExplodedNodeSet &Dst);
    404 
    405   /// VisitObjCForCollectionStmt - Transfer function logic for
    406   ///  ObjCForCollectionStmt.
    407   void VisitObjCForCollectionStmt(const ObjCForCollectionStmt *S,
    408                                   ExplodedNode *Pred, ExplodedNodeSet &Dst);
    409 
    410   void VisitObjCMessage(const ObjCMessageExpr *ME, ExplodedNode *Pred,
    411                         ExplodedNodeSet &Dst);
    412 
    413   /// VisitReturnStmt - Transfer function logic for return statements.
    414   void VisitReturnStmt(const ReturnStmt *R, ExplodedNode *Pred,
    415                        ExplodedNodeSet &Dst);
    416 
    417   /// VisitOffsetOfExpr - Transfer function for offsetof.
    418   void VisitOffsetOfExpr(const OffsetOfExpr *Ex, ExplodedNode *Pred,
    419                          ExplodedNodeSet &Dst);
    420 
    421   /// VisitUnaryExprOrTypeTraitExpr - Transfer function for sizeof.
    422   void VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *Ex,
    423                               ExplodedNode *Pred, ExplodedNodeSet &Dst);
    424 
    425   /// VisitUnaryOperator - Transfer function logic for unary operators.
    426   void VisitUnaryOperator(const UnaryOperator* B, ExplodedNode *Pred,
    427                           ExplodedNodeSet &Dst);
    428 
    429   /// Handle ++ and -- (both pre- and post-increment).
    430   void VisitIncrementDecrementOperator(const UnaryOperator* U,
    431                                        ExplodedNode *Pred,
    432                                        ExplodedNodeSet &Dst);
    433 
    434   void VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr *BTE,
    435                                  ExplodedNodeSet &PreVisit,
    436                                  ExplodedNodeSet &Dst);
    437 
    438   void VisitCXXCatchStmt(const CXXCatchStmt *CS, ExplodedNode *Pred,
    439                          ExplodedNodeSet &Dst);
    440 
    441   void VisitCXXThisExpr(const CXXThisExpr *TE, ExplodedNode *Pred,
    442                         ExplodedNodeSet & Dst);
    443 
    444   void VisitCXXConstructExpr(const CXXConstructExpr *E, ExplodedNode *Pred,
    445                              ExplodedNodeSet &Dst);
    446 
    447   void VisitCXXDestructor(QualType ObjectType, const MemRegion *Dest,
    448                           const Stmt *S, bool IsBaseDtor,
    449                           ExplodedNode *Pred, ExplodedNodeSet &Dst);
    450 
    451   void VisitCXXNewAllocatorCall(const CXXNewExpr *CNE,
    452                                 ExplodedNode *Pred,
    453                                 ExplodedNodeSet &Dst);
    454 
    455   void VisitCXXNewExpr(const CXXNewExpr *CNE, ExplodedNode *Pred,
    456                        ExplodedNodeSet &Dst);
    457 
    458   void VisitCXXDeleteExpr(const CXXDeleteExpr *CDE, ExplodedNode *Pred,
    459                           ExplodedNodeSet &Dst);
    460 
    461   /// Create a C++ temporary object for an rvalue.
    462   void CreateCXXTemporaryObject(const MaterializeTemporaryExpr *ME,
    463                                 ExplodedNode *Pred,
    464                                 ExplodedNodeSet &Dst);
    465 
    466   /// evalEagerlyAssumeBinOpBifurcation - Given the nodes in 'Src', eagerly assume symbolic
    467   ///  expressions of the form 'x != 0' and generate new nodes (stored in Dst)
    468   ///  with those assumptions.
    469   void evalEagerlyAssumeBinOpBifurcation(ExplodedNodeSet &Dst, ExplodedNodeSet &Src,
    470                          const Expr *Ex);
    471 
    472   std::pair<const ProgramPointTag *, const ProgramPointTag*>
    473     geteagerlyAssumeBinOpBifurcationTags();
    474 
    475   SVal evalMinus(SVal X) {
    476     return X.isValid() ? svalBuilder.evalMinus(X.castAs<NonLoc>()) : X;
    477   }
    478 
    479   SVal evalComplement(SVal X) {
    480     return X.isValid() ? svalBuilder.evalComplement(X.castAs<NonLoc>()) : X;
    481   }
    482 
    483   ProgramStateRef handleLValueBitCast(ProgramStateRef state, const Expr *Ex,
    484                                       const LocationContext *LCtx, QualType T,
    485                                       QualType ExTy, const CastExpr *CastE,
    486                                       StmtNodeBuilder &Bldr,
    487                                       ExplodedNode *Pred);
    488 
    489   ProgramStateRef handleLVectorSplat(ProgramStateRef state,
    490                                      const LocationContext *LCtx,
    491                                      const CastExpr *CastE,
    492                                      StmtNodeBuilder &Bldr,
    493                                      ExplodedNode *Pred);
    494 
    495   void handleUOExtension(ExplodedNodeSet::iterator I,
    496                          const UnaryOperator* U,
    497                          StmtNodeBuilder &Bldr);
    498 
    499 public:
    500 
    501   SVal evalBinOp(ProgramStateRef state, BinaryOperator::Opcode op,
    502                  NonLoc L, NonLoc R, QualType T) {
    503     return svalBuilder.evalBinOpNN(state, op, L, R, T);
    504   }
    505 
    506   SVal evalBinOp(ProgramStateRef state, BinaryOperator::Opcode op,
    507                  NonLoc L, SVal R, QualType T) {
    508     return R.isValid() ? svalBuilder.evalBinOpNN(state, op, L,
    509                                                  R.castAs<NonLoc>(), T) : R;
    510   }
    511 
    512   SVal evalBinOp(ProgramStateRef ST, BinaryOperator::Opcode Op,
    513                  SVal LHS, SVal RHS, QualType T) {
    514     return svalBuilder.evalBinOp(ST, Op, LHS, RHS, T);
    515   }
    516 
    517 protected:
    518   /// evalBind - Handle the semantics of binding a value to a specific location.
    519   ///  This method is used by evalStore, VisitDeclStmt, and others.
    520   void evalBind(ExplodedNodeSet &Dst, const Stmt *StoreE, ExplodedNode *Pred,
    521                 SVal location, SVal Val, bool atDeclInit = false,
    522                 const ProgramPoint *PP = nullptr);
    523 
    524   /// Call PointerEscape callback when a value escapes as a result of bind.
    525   ProgramStateRef processPointerEscapedOnBind(ProgramStateRef State,
    526                                               SVal Loc,
    527                                               SVal Val,
    528                                               const LocationContext *LCtx) override;
    529   /// Call PointerEscape callback when a value escapes as a result of
    530   /// region invalidation.
    531   /// \param[in] ITraits Specifies invalidation traits for regions/symbols.
    532   ProgramStateRef notifyCheckersOfPointerEscape(
    533                            ProgramStateRef State,
    534                            const InvalidatedSymbols *Invalidated,
    535                            ArrayRef<const MemRegion *> ExplicitRegions,
    536                            ArrayRef<const MemRegion *> Regions,
    537                            const CallEvent *Call,
    538                            RegionAndSymbolInvalidationTraits &ITraits) override;
    539 
    540 public:
    541   // FIXME: 'tag' should be removed, and a LocationContext should be used
    542   // instead.
    543   // FIXME: Comment on the meaning of the arguments, when 'St' may not
    544   // be the same as Pred->state, and when 'location' may not be the
    545   // same as state->getLValue(Ex).
    546   /// Simulate a read of the result of Ex.
    547   void evalLoad(ExplodedNodeSet &Dst,
    548                 const Expr *NodeEx,  /* Eventually will be a CFGStmt */
    549                 const Expr *BoundExpr,
    550                 ExplodedNode *Pred,
    551                 ProgramStateRef St,
    552                 SVal location,
    553                 const ProgramPointTag *tag = nullptr,
    554                 QualType LoadTy = QualType());
    555 
    556   // FIXME: 'tag' should be removed, and a LocationContext should be used
    557   // instead.
    558   void evalStore(ExplodedNodeSet &Dst, const Expr *AssignE, const Expr *StoreE,
    559                  ExplodedNode *Pred, ProgramStateRef St, SVal TargetLV, SVal Val,
    560                  const ProgramPointTag *tag = nullptr);
    561 
    562   /// \brief Create a new state in which the call return value is binded to the
    563   /// call origin expression.
    564   ProgramStateRef bindReturnValue(const CallEvent &Call,
    565                                   const LocationContext *LCtx,
    566                                   ProgramStateRef State);
    567 
    568   /// Evaluate a call, running pre- and post-call checks and allowing checkers
    569   /// to be responsible for handling the evaluation of the call itself.
    570   void evalCall(ExplodedNodeSet &Dst, ExplodedNode *Pred,
    571                 const CallEvent &Call);
    572 
    573   /// \brief Default implementation of call evaluation.
    574   void defaultEvalCall(NodeBuilder &B, ExplodedNode *Pred,
    575                        const CallEvent &Call);
    576 private:
    577   void evalLoadCommon(ExplodedNodeSet &Dst,
    578                       const Expr *NodeEx,  /* Eventually will be a CFGStmt */
    579                       const Expr *BoundEx,
    580                       ExplodedNode *Pred,
    581                       ProgramStateRef St,
    582                       SVal location,
    583                       const ProgramPointTag *tag,
    584                       QualType LoadTy);
    585 
    586   // FIXME: 'tag' should be removed, and a LocationContext should be used
    587   // instead.
    588   void evalLocation(ExplodedNodeSet &Dst,
    589                     const Stmt *NodeEx, /* This will eventually be a CFGStmt */
    590                     const Stmt *BoundEx,
    591                     ExplodedNode *Pred,
    592                     ProgramStateRef St, SVal location,
    593                     const ProgramPointTag *tag, bool isLoad);
    594 
    595   /// Count the stack depth and determine if the call is recursive.
    596   void examineStackFrames(const Decl *D, const LocationContext *LCtx,
    597                           bool &IsRecursive, unsigned &StackDepth);
    598 
    599   /// Checks our policies and decides weither the given call should be inlined.
    600   bool shouldInlineCall(const CallEvent &Call, const Decl *D,
    601                         const ExplodedNode *Pred);
    602 
    603   bool inlineCall(const CallEvent &Call, const Decl *D, NodeBuilder &Bldr,
    604                   ExplodedNode *Pred, ProgramStateRef State);
    605 
    606   /// \brief Conservatively evaluate call by invalidating regions and binding
    607   /// a conjured return value.
    608   void conservativeEvalCall(const CallEvent &Call, NodeBuilder &Bldr,
    609                             ExplodedNode *Pred, ProgramStateRef State);
    610 
    611   /// \brief Either inline or process the call conservatively (or both), based
    612   /// on DynamicDispatchBifurcation data.
    613   void BifurcateCall(const MemRegion *BifurReg,
    614                      const CallEvent &Call, const Decl *D, NodeBuilder &Bldr,
    615                      ExplodedNode *Pred);
    616 
    617   bool replayWithoutInlining(ExplodedNode *P, const LocationContext *CalleeLC);
    618 
    619   /// Models a trivial copy or move constructor or trivial assignment operator
    620   /// call with a simple bind.
    621   void performTrivialCopy(NodeBuilder &Bldr, ExplodedNode *Pred,
    622                           const CallEvent &Call);
    623 
    624   /// If the value of the given expression \p InitWithAdjustments is a NonLoc,
    625   /// copy it into a new temporary object region, and replace the value of the
    626   /// expression with that.
    627   ///
    628   /// If \p Result is provided, the new region will be bound to this expression
    629   /// instead of \p InitWithAdjustments.
    630   ProgramStateRef createTemporaryRegionIfNeeded(ProgramStateRef State,
    631                                                 const LocationContext *LC,
    632                                                 const Expr *InitWithAdjustments,
    633                                                 const Expr *Result = nullptr);
    634 
    635   /// For a DeclStmt or CXXInitCtorInitializer, walk backward in the current CFG
    636   /// block to find the constructor expression that directly constructed into
    637   /// the storage for this statement. Returns null if the constructor for this
    638   /// statement created a temporary object region rather than directly
    639   /// constructing into an existing region.
    640   const CXXConstructExpr *findDirectConstructorForCurrentCFGElement();
    641 
    642   /// For a CXXConstructExpr, walk forward in the current CFG block to find the
    643   /// CFGElement for the DeclStmt or CXXInitCtorInitializer for which is
    644   /// directly constructed by this constructor. Returns None if the current
    645   /// constructor expression did not directly construct into an existing
    646   /// region.
    647   Optional<CFGElement> findElementDirectlyInitializedByCurrentConstructor();
    648 
    649   /// For a given constructor, look forward in the current CFG block to
    650   /// determine the region into which an object will be constructed by \p CE.
    651   /// Returns either a field or local variable region if the object will be
    652   /// directly constructed in an existing region or a temporary object region
    653   /// if not.
    654   const MemRegion *getRegionForConstructedObject(const CXXConstructExpr *CE,
    655                                                  ExplodedNode *Pred);
    656 };
    657 
    658 /// Traits for storing the call processing policy inside GDM.
    659 /// The GDM stores the corresponding CallExpr pointer.
    660 // FIXME: This does not use the nice trait macros because it must be accessible
    661 // from multiple translation units.
    662 struct ReplayWithoutInlining{};
    663 template <>
    664 struct ProgramStateTrait<ReplayWithoutInlining> :
    665   public ProgramStatePartialTrait<const void*> {
    666   static void *GDMIndex() { static int index = 0; return &index; }
    667 };
    668 
    669 } // end ento namespace
    670 
    671 } // end clang namespace
    672 
    673 #endif
    674