1 //===- ExprEngineCXX.cpp - ExprEngine support for C++ -----------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the C++ expression evaluation engine.
12 //===----------------------------------------------------------------------===//
14 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
15 #include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
16 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
17 #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
18 #include "clang/AST/DeclCXX.h"
19 #include "clang/AST/StmtCXX.h"
20 #include "clang/Basic/PrettyStackTrace.h"
22 using namespace clang;
25 void ExprEngine::CreateCXXTemporaryObject(const MaterializeTemporaryExpr *ME,
27 ExplodedNodeSet &Dst) {
28 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
29 const Expr *tempExpr = ME->GetTemporaryExpr()->IgnoreParens();
30 ProgramStateRef state = Pred->getState();
31 const LocationContext *LCtx = Pred->getLocationContext();
33 // Bind the temporary object to the value of the expression. Then bind
34 // the expression to the location of the object.
35 SVal V = state->getSVal(tempExpr, LCtx);
37 // If the value is already a CXXTempObjectRegion, it is fine as it is.
38 // Otherwise, create a new CXXTempObjectRegion, and copy the value into it.
39 const MemRegion *MR = V.getAsRegion();
40 if (!MR || !isa<CXXTempObjectRegion>(MR)) {
42 svalBuilder.getRegionManager().getCXXTempObjectRegion(ME, LCtx);
44 SVal L = loc::MemRegionVal(R);
45 state = state->bindLoc(L, V);
49 Bldr.generateNode(ME, Pred, state->BindExpr(ME, LCtx, V));
52 void ExprEngine::VisitCXXConstructExpr(const CXXConstructExpr *CE,
54 ExplodedNodeSet &destNodes) {
55 const LocationContext *LCtx = Pred->getLocationContext();
56 ProgramStateRef State = Pred->getState();
58 const MemRegion *Target = 0;
60 switch (CE->getConstructionKind()) {
61 case CXXConstructExpr::CK_Complete: {
62 // See if we're constructing an existing region by looking at the next
63 // element in the CFG.
64 const CFGBlock *B = currBldrCtx->getBlock();
65 if (currStmtIdx + 1 < B->size()) {
66 CFGElement Next = (*B)[currStmtIdx+1];
68 // Is this a constructor for a local variable?
69 if (const CFGStmt *StmtElem = dyn_cast<CFGStmt>(&Next)) {
70 if (const DeclStmt *DS = dyn_cast<DeclStmt>(StmtElem->getStmt())) {
71 if (const VarDecl *Var = dyn_cast<VarDecl>(DS->getSingleDecl())) {
72 if (Var->getInit()->IgnoreImplicit() == CE) {
73 QualType Ty = Var->getType();
74 if (const ArrayType *AT = getContext().getAsArrayType(Ty)) {
75 // FIXME: Handle arrays, which run the same constructor for
76 // every element. This workaround will just run the first
77 // constructor (which should still invalidate the entire array).
78 SVal Base = State->getLValue(Var, LCtx);
79 Target = State->getLValue(AT->getElementType(),
80 getSValBuilder().makeZeroArrayIndex(),
83 Target = State->getLValue(Var, LCtx).getAsRegion();
90 // Is this a constructor for a member?
91 if (const CFGInitializer *InitElem = dyn_cast<CFGInitializer>(&Next)) {
92 const CXXCtorInitializer *Init = InitElem->getInitializer();
93 assert(Init->isAnyMemberInitializer());
95 const CXXMethodDecl *CurCtor = cast<CXXMethodDecl>(LCtx->getDecl());
96 Loc ThisPtr = getSValBuilder().getCXXThis(CurCtor,
97 LCtx->getCurrentStackFrame());
98 SVal ThisVal = State->getSVal(ThisPtr);
100 if (Init->isIndirectMemberInitializer()) {
101 SVal Field = State->getLValue(Init->getIndirectMember(), ThisVal);
102 Target = Field.getAsRegion();
104 SVal Field = State->getLValue(Init->getMember(), ThisVal);
105 Target = Field.getAsRegion();
109 // FIXME: This will eventually need to handle new-expressions as well.
112 // If we couldn't find an existing region to construct into, assume we're
113 // constructing a temporary.
115 MemRegionManager &MRMgr = getSValBuilder().getRegionManager();
116 Target = MRMgr.getCXXTempObjectRegion(CE, LCtx);
121 case CXXConstructExpr::CK_NonVirtualBase:
122 case CXXConstructExpr::CK_VirtualBase:
123 case CXXConstructExpr::CK_Delegating: {
124 const CXXMethodDecl *CurCtor = cast<CXXMethodDecl>(LCtx->getDecl());
125 Loc ThisPtr = getSValBuilder().getCXXThis(CurCtor,
126 LCtx->getCurrentStackFrame());
127 SVal ThisVal = State->getSVal(ThisPtr);
129 if (CE->getConstructionKind() == CXXConstructExpr::CK_Delegating) {
130 Target = ThisVal.getAsRegion();
132 // Cast to the base type.
133 QualType BaseTy = CE->getType();
134 SVal BaseVal = getStoreManager().evalDerivedToBase(ThisVal, BaseTy);
135 Target = BaseVal.getAsRegion();
141 CallEventManager &CEMgr = getStateManager().getCallEventManager();
142 CallEventRef<CXXConstructorCall> Call =
143 CEMgr.getCXXConstructorCall(CE, Target, State, LCtx);
145 ExplodedNodeSet DstPreVisit;
146 getCheckerManager().runCheckersForPreStmt(DstPreVisit, Pred, CE, *this);
147 ExplodedNodeSet DstPreCall;
148 getCheckerManager().runCheckersForPreCall(DstPreCall, DstPreVisit,
151 ExplodedNodeSet DstInvalidated;
152 StmtNodeBuilder Bldr(DstPreCall, DstInvalidated, *currBldrCtx);
153 for (ExplodedNodeSet::iterator I = DstPreCall.begin(), E = DstPreCall.end();
155 defaultEvalCall(Bldr, *I, *Call);
157 ExplodedNodeSet DstPostCall;
158 getCheckerManager().runCheckersForPostCall(DstPostCall, DstInvalidated,
160 getCheckerManager().runCheckersForPostStmt(destNodes, DstPostCall, CE, *this);
163 void ExprEngine::VisitCXXDestructor(QualType ObjectType,
164 const MemRegion *Dest,
168 ExplodedNodeSet &Dst) {
169 const LocationContext *LCtx = Pred->getLocationContext();
170 ProgramStateRef State = Pred->getState();
172 // FIXME: We need to run the same destructor on every element of the array.
173 // This workaround will just run the first destructor (which will still
174 // invalidate the entire array).
175 if (const ArrayType *AT = getContext().getAsArrayType(ObjectType)) {
176 ObjectType = AT->getElementType();
177 Dest = State->getLValue(ObjectType, getSValBuilder().makeZeroArrayIndex(),
178 loc::MemRegionVal(Dest)).getAsRegion();
181 const CXXRecordDecl *RecordDecl = ObjectType->getAsCXXRecordDecl();
182 assert(RecordDecl && "Only CXXRecordDecls should have destructors");
183 const CXXDestructorDecl *DtorDecl = RecordDecl->getDestructor();
185 CallEventManager &CEMgr = getStateManager().getCallEventManager();
186 CallEventRef<CXXDestructorCall> Call =
187 CEMgr.getCXXDestructorCall(DtorDecl, S, Dest, IsBaseDtor, State, LCtx);
189 PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(),
190 Call->getSourceRange().getBegin(),
191 "Error evaluating destructor");
193 ExplodedNodeSet DstPreCall;
194 getCheckerManager().runCheckersForPreCall(DstPreCall, Pred,
197 ExplodedNodeSet DstInvalidated;
198 StmtNodeBuilder Bldr(DstPreCall, DstInvalidated, *currBldrCtx);
199 for (ExplodedNodeSet::iterator I = DstPreCall.begin(), E = DstPreCall.end();
201 defaultEvalCall(Bldr, *I, *Call);
203 ExplodedNodeSet DstPostCall;
204 getCheckerManager().runCheckersForPostCall(Dst, DstInvalidated,
208 void ExprEngine::VisitCXXNewExpr(const CXXNewExpr *CNE, ExplodedNode *Pred,
209 ExplodedNodeSet &Dst) {
210 // FIXME: Much of this should eventually migrate to CXXAllocatorCall.
211 // Also, we need to decide how allocators actually work -- they're not
212 // really part of the CXXNewExpr because they happen BEFORE the
213 // CXXConstructExpr subexpression. See PR12014 for some discussion.
214 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
216 unsigned blockCount = currBldrCtx->blockCount();
217 const LocationContext *LCtx = Pred->getLocationContext();
218 DefinedOrUnknownSVal symVal = svalBuilder.conjureSymbolVal(0, CNE, LCtx,
221 ProgramStateRef State = Pred->getState();
223 CallEventManager &CEMgr = getStateManager().getCallEventManager();
224 CallEventRef<CXXAllocatorCall> Call =
225 CEMgr.getCXXAllocatorCall(CNE, State, LCtx);
227 // Invalidate placement args.
228 // FIXME: Once we figure out how we want allocators to work,
229 // we should be using the usual pre-/(default-)eval-/post-call checks here.
230 State = Call->invalidateRegions(blockCount);
232 // If we're compiling with exceptions enabled, and this allocation function
233 // is not declared as non-throwing, failures /must/ be signalled by
234 // exceptions, and thus the return value will never be NULL.
235 // C++11 [basic.stc.dynamic.allocation]p3.
236 FunctionDecl *FD = CNE->getOperatorNew();
237 if (FD && getContext().getLangOpts().CXXExceptions) {
238 QualType Ty = FD->getType();
239 if (const FunctionProtoType *ProtoType = Ty->getAs<FunctionProtoType>())
240 if (!ProtoType->isNothrow(getContext()))
241 State = State->assume(symVal, true);
244 if (CNE->isArray()) {
245 // FIXME: allocating an array requires simulating the constructors.
246 // For now, just return a symbolicated region.
247 const MemRegion *NewReg = cast<loc::MemRegionVal>(symVal).getRegion();
248 QualType ObjTy = CNE->getType()->getAs<PointerType>()->getPointeeType();
249 const ElementRegion *EleReg =
250 getStoreManager().GetElementZeroRegion(NewReg, ObjTy);
251 State = State->BindExpr(CNE, Pred->getLocationContext(),
252 loc::MemRegionVal(EleReg));
253 Bldr.generateNode(CNE, Pred, State);
257 // FIXME: Once we have proper support for CXXConstructExprs inside
258 // CXXNewExpr, we need to make sure that the constructed object is not
259 // immediately invalidated here. (The placement call should happen before
260 // the constructor call anyway.)
261 if (FD && FD->isReservedGlobalPlacementOperator()) {
262 // Non-array placement new should always return the placement location.
263 SVal PlacementLoc = State->getSVal(CNE->getPlacementArg(0), LCtx);
264 SVal Result = svalBuilder.evalCast(PlacementLoc, CNE->getType(),
265 CNE->getPlacementArg(0)->getType());
266 State = State->BindExpr(CNE, LCtx, Result);
268 State = State->BindExpr(CNE, LCtx, symVal);
271 // If the type is not a record, we won't have a CXXConstructExpr as an
272 // initializer. Copy the value over.
273 if (const Expr *Init = CNE->getInitializer()) {
274 if (!isa<CXXConstructExpr>(Init)) {
275 QualType ObjTy = CNE->getType()->getAs<PointerType>()->getPointeeType();
277 assert(!ObjTy->isRecordType());
278 SVal Location = State->getSVal(CNE, LCtx);
279 if (isa<Loc>(Location))
280 State = State->bindLoc(cast<Loc>(Location), State->getSVal(Init, LCtx));
284 Bldr.generateNode(CNE, Pred, State);
287 void ExprEngine::VisitCXXDeleteExpr(const CXXDeleteExpr *CDE,
288 ExplodedNode *Pred, ExplodedNodeSet &Dst) {
289 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
290 ProgramStateRef state = Pred->getState();
291 Bldr.generateNode(CDE, Pred, state);
294 void ExprEngine::VisitCXXCatchStmt(const CXXCatchStmt *CS,
296 ExplodedNodeSet &Dst) {
297 const VarDecl *VD = CS->getExceptionDecl();
303 const LocationContext *LCtx = Pred->getLocationContext();
304 SVal V = svalBuilder.conjureSymbolVal(CS, LCtx, VD->getType(),
305 currBldrCtx->blockCount());
306 ProgramStateRef state = Pred->getState();
307 state = state->bindLoc(state->getLValue(VD, LCtx), V);
309 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
310 Bldr.generateNode(CS, Pred, state);
313 void ExprEngine::VisitCXXThisExpr(const CXXThisExpr *TE, ExplodedNode *Pred,
314 ExplodedNodeSet &Dst) {
315 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
317 // Get the this object region from StoreManager.
318 const LocationContext *LCtx = Pred->getLocationContext();
320 svalBuilder.getRegionManager().getCXXThisRegion(
321 getContext().getCanonicalType(TE->getType()),
324 ProgramStateRef state = Pred->getState();
325 SVal V = state->getSVal(loc::MemRegionVal(R));
326 Bldr.generateNode(TE, Pred, state->BindExpr(TE, LCtx, V));