lib/StaticAnalyzer/Core/ExprEngineCXX.cpp - platform/external/clang - Git at Google

 //===- ExprEngineCXX.cpp - ExprEngine support for C++ -----------*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 //  This file defines the C++ expression evaluation engine.
 //
 //===----------------------------------------------------------------------===//

 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
 #include "clang/AST/DeclCXX.h"
 #include "clang/AST/StmtCXX.h"
 #include "clang/Basic/PrettyStackTrace.h"

 using namespace clang;
 using namespace ento;

 void ExprEngine::CreateCXXTemporaryObject(const MaterializeTemporaryExpr *ME,
                                           ExplodedNode *Pred,
                                           ExplodedNodeSet &Dst) {
   StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
   const Expr *tempExpr = ME->GetTemporaryExpr()->IgnoreParens();
   ProgramStateRef state = Pred->getState();
   const LocationContext *LCtx = Pred->getLocationContext();

   // Bind the temporary object to the value of the expression. Then bind
   // the expression to the location of the object.
   SVal V = state->getSVal(tempExpr, LCtx);

   // If the value is already a CXXTempObjectRegion, it is fine as it is.
   // Otherwise, create a new CXXTempObjectRegion, and copy the value into it.
   const MemRegion *MR = V.getAsRegion();
   if (!MR || !isa<CXXTempObjectRegion>(MR)) {
     const MemRegion *R =
       svalBuilder.getRegionManager().getCXXTempObjectRegion(ME, LCtx);

     SVal L = loc::MemRegionVal(R);
     state = state->bindLoc(L, V);
     V = L;
   }

   Bldr.generateNode(ME, Pred, state->BindExpr(ME, LCtx, V));
 }

 void ExprEngine::VisitCXXConstructExpr(const CXXConstructExpr *CE,
                                        ExplodedNode *Pred,
                                        ExplodedNodeSet &destNodes) {
   const LocationContext *LCtx = Pred->getLocationContext();
   ProgramStateRef State = Pred->getState();

   const MemRegion *Target = 0;

   switch (CE->getConstructionKind()) {
   case CXXConstructExpr::CK_Complete: {
     // See if we're constructing an existing region by looking at the next
     // element in the CFG.
     const CFGBlock *B = currBldrCtx->getBlock();
     if (currStmtIdx + 1 < B->size()) {
       CFGElement Next = (*B)[currStmtIdx+1];

       // Is this a constructor for a local variable?
       if (const CFGStmt *StmtElem = dyn_cast<CFGStmt>(&Next)) {
         if (const DeclStmt *DS = dyn_cast<DeclStmt>(StmtElem->getStmt())) {
           if (const VarDecl *Var = dyn_cast<VarDecl>(DS->getSingleDecl())) {
             if (Var->getInit()->IgnoreImplicit() == CE) {
               QualType Ty = Var->getType();
               if (const ArrayType *AT = getContext().getAsArrayType(Ty)) {
                 // FIXME: Handle arrays, which run the same constructor for
                 // every element. This workaround will just run the first
                 // constructor (which should still invalidate the entire array).
                 SVal Base = State->getLValue(Var, LCtx);
                 Target = State->getLValue(AT->getElementType(),
                                           getSValBuilder().makeZeroArrayIndex(),
                                           Base).getAsRegion();
               } else {
                 Target = State->getLValue(Var, LCtx).getAsRegion();
               }
             }
           }
         }
       }

       // Is this a constructor for a member?
       if (const CFGInitializer *InitElem = dyn_cast<CFGInitializer>(&Next)) {
         const CXXCtorInitializer *Init = InitElem->getInitializer();
         assert(Init->isAnyMemberInitializer());

         const CXXMethodDecl *CurCtor = cast<CXXMethodDecl>(LCtx->getDecl());
         Loc ThisPtr = getSValBuilder().getCXXThis(CurCtor,
                                                   LCtx->getCurrentStackFrame());
         SVal ThisVal = State->getSVal(ThisPtr);

         if (Init->isIndirectMemberInitializer()) {
           SVal Field = State->getLValue(Init->getIndirectMember(), ThisVal);
           Target = Field.getAsRegion();
         } else {
           SVal Field = State->getLValue(Init->getMember(), ThisVal);
           Target = Field.getAsRegion();
         }
       }

       // FIXME: This will eventually need to handle new-expressions as well.
     }

     // If we couldn't find an existing region to construct into, assume we're
     // constructing a temporary.
     if (!Target) {
       MemRegionManager &MRMgr = getSValBuilder().getRegionManager();
       Target = MRMgr.getCXXTempObjectRegion(CE, LCtx);
     }

     break;
   }
   case CXXConstructExpr::CK_NonVirtualBase:
   case CXXConstructExpr::CK_VirtualBase:
   case CXXConstructExpr::CK_Delegating: {
     const CXXMethodDecl *CurCtor = cast<CXXMethodDecl>(LCtx->getDecl());
     Loc ThisPtr = getSValBuilder().getCXXThis(CurCtor,
                                               LCtx->getCurrentStackFrame());
     SVal ThisVal = State->getSVal(ThisPtr);

     if (CE->getConstructionKind() == CXXConstructExpr::CK_Delegating) {
       Target = ThisVal.getAsRegion();
     } else {
       // Cast to the base type.
       QualType BaseTy = CE->getType();
       SVal BaseVal = getStoreManager().evalDerivedToBase(ThisVal, BaseTy);
       Target = BaseVal.getAsRegion();
     }
     break;
   }
   }

   CallEventManager &CEMgr = getStateManager().getCallEventManager();
   CallEventRef<CXXConstructorCall> Call =
     CEMgr.getCXXConstructorCall(CE, Target, State, LCtx);

   ExplodedNodeSet DstPreVisit;
   getCheckerManager().runCheckersForPreStmt(DstPreVisit, Pred, CE, *this);
   ExplodedNodeSet DstPreCall;
   getCheckerManager().runCheckersForPreCall(DstPreCall, DstPreVisit,
                                             *Call, *this);

   ExplodedNodeSet DstInvalidated;
   StmtNodeBuilder Bldr(DstPreCall, DstInvalidated, *currBldrCtx);
   for (ExplodedNodeSet::iterator I = DstPreCall.begin(), E = DstPreCall.end();
        I != E; ++I)
     defaultEvalCall(Bldr, *I, *Call);

   ExplodedNodeSet DstPostCall;
   getCheckerManager().runCheckersForPostCall(DstPostCall, DstInvalidated,
                                              *Call, *this);
   getCheckerManager().runCheckersForPostStmt(destNodes, DstPostCall, CE, *this);
 }

 void ExprEngine::VisitCXXDestructor(QualType ObjectType,
                                     const MemRegion *Dest,
                                     const Stmt *S,
                                     ExplodedNode *Pred,
                                     ExplodedNodeSet &Dst) {
   const LocationContext *LCtx = Pred->getLocationContext();
   ProgramStateRef State = Pred->getState();

   // FIXME: We need to run the same destructor on every element of the array.
   // This workaround will just run the first destructor (which will still
   // invalidate the entire array).
   if (const ArrayType *AT = getContext().getAsArrayType(ObjectType)) {
     ObjectType = AT->getElementType();
     Dest = State->getLValue(ObjectType, getSValBuilder().makeZeroArrayIndex(),
                             loc::MemRegionVal(Dest)).getAsRegion();
   }

   const CXXRecordDecl *RecordDecl = ObjectType->getAsCXXRecordDecl();
   assert(RecordDecl && "Only CXXRecordDecls should have destructors");
   const CXXDestructorDecl *DtorDecl = RecordDecl->getDestructor();

   CallEventManager &CEMgr = getStateManager().getCallEventManager();
   CallEventRef<CXXDestructorCall> Call =
     CEMgr.getCXXDestructorCall(DtorDecl, S, Dest, State, LCtx);

   PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(),
                                 Call->getSourceRange().getBegin(),
                                 "Error evaluating destructor");

   ExplodedNodeSet DstPreCall;
   getCheckerManager().runCheckersForPreCall(DstPreCall, Pred,
                                             *Call, *this);

   ExplodedNodeSet DstInvalidated;
   StmtNodeBuilder Bldr(DstPreCall, DstInvalidated, *currBldrCtx);
   for (ExplodedNodeSet::iterator I = DstPreCall.begin(), E = DstPreCall.end();
        I != E; ++I)
     defaultEvalCall(Bldr, *I, *Call);

   ExplodedNodeSet DstPostCall;
   getCheckerManager().runCheckersForPostCall(Dst, DstInvalidated,
                                              *Call, *this);
 }

 void ExprEngine::VisitCXXNewExpr(const CXXNewExpr *CNE, ExplodedNode *Pred,
                                    ExplodedNodeSet &Dst) {
   // FIXME: Much of this should eventually migrate to CXXAllocatorCall.
   // Also, we need to decide how allocators actually work -- they're not
   // really part of the CXXNewExpr because they happen BEFORE the
   // CXXConstructExpr subexpression. See PR12014 for some discussion.
   StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);

   unsigned blockCount = currBldrCtx->blockCount();
   const LocationContext *LCtx = Pred->getLocationContext();
   DefinedOrUnknownSVal symVal = svalBuilder.conjureSymbolVal(0, CNE, LCtx,
                                                              CNE->getType(),
                                                              blockCount);
   ProgramStateRef State = Pred->getState();

   CallEventManager &CEMgr = getStateManager().getCallEventManager();
   CallEventRef<CXXAllocatorCall> Call =
     CEMgr.getCXXAllocatorCall(CNE, State, LCtx);

   // Invalidate placement args.
   // FIXME: Once we figure out how we want allocators to work,
   // we should be using the usual pre-/(default-)eval-/post-call checks here.
   State = Call->invalidateRegions(blockCount);

   if (CNE->isArray()) {
     // FIXME: allocating an array requires simulating the constructors.
     // For now, just return a symbolicated region.
     const MemRegion *NewReg = cast<loc::MemRegionVal>(symVal).getRegion();
     QualType ObjTy = CNE->getType()->getAs<PointerType>()->getPointeeType();
     const ElementRegion *EleReg =
       getStoreManager().GetElementZeroRegion(NewReg, ObjTy);
     State = State->BindExpr(CNE, Pred->getLocationContext(),
                             loc::MemRegionVal(EleReg));
     Bldr.generateNode(CNE, Pred, State);
     return;
   }

   // FIXME: Once we have proper support for CXXConstructExprs inside
   // CXXNewExpr, we need to make sure that the constructed object is not
   // immediately invalidated here. (The placement call should happen before
   // the constructor call anyway.)
   FunctionDecl *FD = CNE->getOperatorNew();
   if (FD && FD->isReservedGlobalPlacementOperator()) {
     // Non-array placement new should always return the placement location.
     SVal PlacementLoc = State->getSVal(CNE->getPlacementArg(0), LCtx);
     State = State->BindExpr(CNE, LCtx, PlacementLoc);
   } else {
     State = State->BindExpr(CNE, LCtx, symVal);
   }

   // If the type is not a record, we won't have a CXXConstructExpr as an
   // initializer. Copy the value over.
   if (const Expr *Init = CNE->getInitializer()) {
     if (!isa<CXXConstructExpr>(Init)) {
       QualType ObjTy = CNE->getType()->getAs<PointerType>()->getPointeeType();
       (void)ObjTy;
       assert(!ObjTy->isRecordType());
       SVal Location = State->getSVal(CNE, LCtx);
       if (isa<Loc>(Location))
         State = State->bindLoc(cast<Loc>(Location), State->getSVal(Init, LCtx));
     }
   }

   Bldr.generateNode(CNE, Pred, State);
 }

 void ExprEngine::VisitCXXDeleteExpr(const CXXDeleteExpr *CDE,
                                     ExplodedNode *Pred, ExplodedNodeSet &Dst) {
   StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
   ProgramStateRef state = Pred->getState();
   Bldr.generateNode(CDE, Pred, state);
 }

 void ExprEngine::VisitCXXCatchStmt(const CXXCatchStmt *CS,
                                    ExplodedNode *Pred,
                                    ExplodedNodeSet &Dst) {
   const VarDecl *VD = CS->getExceptionDecl();
   if (!VD) {
     Dst.Add(Pred);
     return;
   }

   const LocationContext *LCtx = Pred->getLocationContext();
   SVal V = svalBuilder.conjureSymbolVal(CS, LCtx, VD->getType(),
                                         currBldrCtx->blockCount());
   ProgramStateRef state = Pred->getState();
   state = state->bindLoc(state->getLValue(VD, LCtx), V);

   StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
   Bldr.generateNode(CS, Pred, state);
 }

 void ExprEngine::VisitCXXThisExpr(const CXXThisExpr *TE, ExplodedNode *Pred,
                                     ExplodedNodeSet &Dst) {
   StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);

   // Get the this object region from StoreManager.
   const LocationContext *LCtx = Pred->getLocationContext();
   const MemRegion *R =
     svalBuilder.getRegionManager().getCXXThisRegion(
                                   getContext().getCanonicalType(TE->getType()),
                                                     LCtx);

   ProgramStateRef state = Pred->getState();
   SVal V = state->getSVal(loc::MemRegionVal(R));
   Bldr.generateNode(TE, Pred, state->BindExpr(TE, LCtx, V));
 }
	//===- ExprEngineCXX.cpp - ExprEngine support for C++ ------------ C++ --===//
	//
	// The LLVM Compiler Infrastructure
	//
	// This file is distributed under the University of Illinois Open Source
	// License. See LICENSE.TXT for details.
	//
	//===----------------------------------------------------------------------===//
	//
	// This file defines the C++ expression evaluation engine.
	//
	//===----------------------------------------------------------------------===//

	#include "clang/StaticAnalyzer/Core/CheckerManager.h"
	#include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
	#include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
	#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
	#include "clang/AST/DeclCXX.h"
	#include "clang/AST/StmtCXX.h"
	#include "clang/Basic/PrettyStackTrace.h"

	using namespace clang;
	using namespace ento;

	void ExprEngine::CreateCXXTemporaryObject(const MaterializeTemporaryExpr *ME,
	ExplodedNode *Pred,
	ExplodedNodeSet &Dst) {
	StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
	const Expr *tempExpr = ME->GetTemporaryExpr()->IgnoreParens();
	ProgramStateRef state = Pred->getState();
	const LocationContext *LCtx = Pred->getLocationContext();

	// Bind the temporary object to the value of the expression. Then bind
	// the expression to the location of the object.
	SVal V = state->getSVal(tempExpr, LCtx);

	// If the value is already a CXXTempObjectRegion, it is fine as it is.
	// Otherwise, create a new CXXTempObjectRegion, and copy the value into it.
	const MemRegion *MR = V.getAsRegion();
	if (!MR \|\| !isa<CXXTempObjectRegion>(MR)) {
	const MemRegion *R =
	svalBuilder.getRegionManager().getCXXTempObjectRegion(ME, LCtx);

	SVal L = loc::MemRegionVal(R);
	state = state->bindLoc(L, V);
	V = L;
	}

	Bldr.generateNode(ME, Pred, state->BindExpr(ME, LCtx, V));
	}

	void ExprEngine::VisitCXXConstructExpr(const CXXConstructExpr *CE,
	ExplodedNode *Pred,
	ExplodedNodeSet &destNodes) {
	const LocationContext *LCtx = Pred->getLocationContext();
	ProgramStateRef State = Pred->getState();

	const MemRegion *Target = 0;

	switch (CE->getConstructionKind()) {
	case CXXConstructExpr::CK_Complete: {
	// See if we're constructing an existing region by looking at the next
	// element in the CFG.
	const CFGBlock *B = currBldrCtx->getBlock();
	if (currStmtIdx + 1 < B->size()) {
	CFGElement Next = (*B)[currStmtIdx+1];

	// Is this a constructor for a local variable?
	if (const CFGStmt *StmtElem = dyn_cast<CFGStmt>(&Next)) {
	if (const DeclStmt *DS = dyn_cast<DeclStmt>(StmtElem->getStmt())) {
	if (const VarDecl *Var = dyn_cast<VarDecl>(DS->getSingleDecl())) {
	if (Var->getInit()->IgnoreImplicit() == CE) {
	QualType Ty = Var->getType();
	if (const ArrayType *AT = getContext().getAsArrayType(Ty)) {
	// FIXME: Handle arrays, which run the same constructor for
	// every element. This workaround will just run the first
	// constructor (which should still invalidate the entire array).
	SVal Base = State->getLValue(Var, LCtx);
	Target = State->getLValue(AT->getElementType(),
	getSValBuilder().makeZeroArrayIndex(),
	Base).getAsRegion();
	} else {
	Target = State->getLValue(Var, LCtx).getAsRegion();
	}
	}
	}
	}
	}

	// Is this a constructor for a member?
	if (const CFGInitializer *InitElem = dyn_cast<CFGInitializer>(&Next)) {
	const CXXCtorInitializer *Init = InitElem->getInitializer();
	assert(Init->isAnyMemberInitializer());

	const CXXMethodDecl *CurCtor = cast<CXXMethodDecl>(LCtx->getDecl());
	Loc ThisPtr = getSValBuilder().getCXXThis(CurCtor,
	LCtx->getCurrentStackFrame());
	SVal ThisVal = State->getSVal(ThisPtr);

	if (Init->isIndirectMemberInitializer()) {
	SVal Field = State->getLValue(Init->getIndirectMember(), ThisVal);
	Target = Field.getAsRegion();
	} else {
	SVal Field = State->getLValue(Init->getMember(), ThisVal);
	Target = Field.getAsRegion();
	}
	}

	// FIXME: This will eventually need to handle new-expressions as well.
	}

	// If we couldn't find an existing region to construct into, assume we're
	// constructing a temporary.
	if (!Target) {
	MemRegionManager &MRMgr = getSValBuilder().getRegionManager();
	Target = MRMgr.getCXXTempObjectRegion(CE, LCtx);
	}

	break;
	}
	case CXXConstructExpr::CK_NonVirtualBase:
	case CXXConstructExpr::CK_VirtualBase:
	case CXXConstructExpr::CK_Delegating: {
	const CXXMethodDecl *CurCtor = cast<CXXMethodDecl>(LCtx->getDecl());
	Loc ThisPtr = getSValBuilder().getCXXThis(CurCtor,
	LCtx->getCurrentStackFrame());
	SVal ThisVal = State->getSVal(ThisPtr);

	if (CE->getConstructionKind() == CXXConstructExpr::CK_Delegating) {
	Target = ThisVal.getAsRegion();
	} else {
	// Cast to the base type.
	QualType BaseTy = CE->getType();
	SVal BaseVal = getStoreManager().evalDerivedToBase(ThisVal, BaseTy);
	Target = BaseVal.getAsRegion();
	}
	break;
	}
	}

	CallEventManager &CEMgr = getStateManager().getCallEventManager();
	CallEventRef<CXXConstructorCall> Call =
	CEMgr.getCXXConstructorCall(CE, Target, State, LCtx);

	ExplodedNodeSet DstPreVisit;
	getCheckerManager().runCheckersForPreStmt(DstPreVisit, Pred, CE, *this);
	ExplodedNodeSet DstPreCall;
	getCheckerManager().runCheckersForPreCall(DstPreCall, DstPreVisit,
	Call, this);

	ExplodedNodeSet DstInvalidated;
	StmtNodeBuilder Bldr(DstPreCall, DstInvalidated, *currBldrCtx);
	for (ExplodedNodeSet::iterator I = DstPreCall.begin(), E = DstPreCall.end();
	I != E; ++I)
	defaultEvalCall(Bldr, I, Call);

	ExplodedNodeSet DstPostCall;
	getCheckerManager().runCheckersForPostCall(DstPostCall, DstInvalidated,
	Call, this);
	getCheckerManager().runCheckersForPostStmt(destNodes, DstPostCall, CE, *this);
	}

	void ExprEngine::VisitCXXDestructor(QualType ObjectType,
	const MemRegion *Dest,
	const Stmt *S,
	ExplodedNode *Pred,
	ExplodedNodeSet &Dst) {
	const LocationContext *LCtx = Pred->getLocationContext();
	ProgramStateRef State = Pred->getState();

	// FIXME: We need to run the same destructor on every element of the array.
	// This workaround will just run the first destructor (which will still
	// invalidate the entire array).
	if (const ArrayType *AT = getContext().getAsArrayType(ObjectType)) {
	ObjectType = AT->getElementType();
	Dest = State->getLValue(ObjectType, getSValBuilder().makeZeroArrayIndex(),
	loc::MemRegionVal(Dest)).getAsRegion();
	}

	const CXXRecordDecl *RecordDecl = ObjectType->getAsCXXRecordDecl();
	assert(RecordDecl && "Only CXXRecordDecls should have destructors");
	const CXXDestructorDecl *DtorDecl = RecordDecl->getDestructor();

	CallEventManager &CEMgr = getStateManager().getCallEventManager();
	CallEventRef<CXXDestructorCall> Call =
	CEMgr.getCXXDestructorCall(DtorDecl, S, Dest, State, LCtx);

	PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(),
	Call->getSourceRange().getBegin(),
	"Error evaluating destructor");

	ExplodedNodeSet DstPreCall;
	getCheckerManager().runCheckersForPreCall(DstPreCall, Pred,
	Call, this);

	ExplodedNodeSet DstInvalidated;
	StmtNodeBuilder Bldr(DstPreCall, DstInvalidated, *currBldrCtx);
	for (ExplodedNodeSet::iterator I = DstPreCall.begin(), E = DstPreCall.end();
	I != E; ++I)
	defaultEvalCall(Bldr, I, Call);

	ExplodedNodeSet DstPostCall;
	getCheckerManager().runCheckersForPostCall(Dst, DstInvalidated,
	Call, this);
	}

	void ExprEngine::VisitCXXNewExpr(const CXXNewExpr CNE, ExplodedNode Pred,
	ExplodedNodeSet &Dst) {
	// FIXME: Much of this should eventually migrate to CXXAllocatorCall.
	// Also, we need to decide how allocators actually work -- they're not
	// really part of the CXXNewExpr because they happen BEFORE the
	// CXXConstructExpr subexpression. See PR12014 for some discussion.
	StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);

	unsigned blockCount = currBldrCtx->blockCount();
	const LocationContext *LCtx = Pred->getLocationContext();
	DefinedOrUnknownSVal symVal = svalBuilder.conjureSymbolVal(0, CNE, LCtx,
	CNE->getType(),
	blockCount);
	ProgramStateRef State = Pred->getState();

	CallEventManager &CEMgr = getStateManager().getCallEventManager();
	CallEventRef<CXXAllocatorCall> Call =
	CEMgr.getCXXAllocatorCall(CNE, State, LCtx);

	// Invalidate placement args.
	// FIXME: Once we figure out how we want allocators to work,
	// we should be using the usual pre-/(default-)eval-/post-call checks here.
	State = Call->invalidateRegions(blockCount);

	if (CNE->isArray()) {
	// FIXME: allocating an array requires simulating the constructors.
	// For now, just return a symbolicated region.
	const MemRegion *NewReg = cast<loc::MemRegionVal>(symVal).getRegion();
	QualType ObjTy = CNE->getType()->getAs<PointerType>()->getPointeeType();
	const ElementRegion *EleReg =
	getStoreManager().GetElementZeroRegion(NewReg, ObjTy);
	State = State->BindExpr(CNE, Pred->getLocationContext(),
	loc::MemRegionVal(EleReg));
	Bldr.generateNode(CNE, Pred, State);
	return;
	}

	// FIXME: Once we have proper support for CXXConstructExprs inside
	// CXXNewExpr, we need to make sure that the constructed object is not
	// immediately invalidated here. (The placement call should happen before
	// the constructor call anyway.)
	FunctionDecl *FD = CNE->getOperatorNew();
	if (FD && FD->isReservedGlobalPlacementOperator()) {
	// Non-array placement new should always return the placement location.
	SVal PlacementLoc = State->getSVal(CNE->getPlacementArg(0), LCtx);
	State = State->BindExpr(CNE, LCtx, PlacementLoc);
	} else {
	State = State->BindExpr(CNE, LCtx, symVal);
	}

	// If the type is not a record, we won't have a CXXConstructExpr as an
	// initializer. Copy the value over.
	if (const Expr *Init = CNE->getInitializer()) {
	if (!isa<CXXConstructExpr>(Init)) {
	QualType ObjTy = CNE->getType()->getAs<PointerType>()->getPointeeType();
	(void)ObjTy;
	assert(!ObjTy->isRecordType());
	SVal Location = State->getSVal(CNE, LCtx);
	if (isa<Loc>(Location))
	State = State->bindLoc(cast<Loc>(Location), State->getSVal(Init, LCtx));
	}
	}

	Bldr.generateNode(CNE, Pred, State);
	}

	void ExprEngine::VisitCXXDeleteExpr(const CXXDeleteExpr *CDE,
	ExplodedNode *Pred, ExplodedNodeSet &Dst) {
	StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
	ProgramStateRef state = Pred->getState();
	Bldr.generateNode(CDE, Pred, state);
	}

	void ExprEngine::VisitCXXCatchStmt(const CXXCatchStmt *CS,
	ExplodedNode *Pred,
	ExplodedNodeSet &Dst) {
	const VarDecl *VD = CS->getExceptionDecl();
	if (!VD) {
	Dst.Add(Pred);
	return;
	}

	const LocationContext *LCtx = Pred->getLocationContext();
	SVal V = svalBuilder.conjureSymbolVal(CS, LCtx, VD->getType(),
	currBldrCtx->blockCount());
	ProgramStateRef state = Pred->getState();
	state = state->bindLoc(state->getLValue(VD, LCtx), V);

	StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
	Bldr.generateNode(CS, Pred, state);
	}

	void ExprEngine::VisitCXXThisExpr(const CXXThisExpr TE, ExplodedNode Pred,
	ExplodedNodeSet &Dst) {
	StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);

	// Get the this object region from StoreManager.
	const LocationContext *LCtx = Pred->getLocationContext();
	const MemRegion *R =
	svalBuilder.getRegionManager().getCXXThisRegion(
	getContext().getCanonicalType(TE->getType()),
	LCtx);

	ProgramStateRef state = Pred->getState();
	SVal V = state->getSVal(loc::MemRegionVal(R));
	Bldr.generateNode(TE, Pred, state->BindExpr(TE, LCtx, V));
	}