| //===- GRCXXExprEngine.cpp - C++ expr evaluation engine ---------*- 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/AST/DeclCXX.h" |
| |
| using namespace clang; |
| using namespace ento; |
| |
| namespace { |
| class CallExprWLItem { |
| public: |
| CallExpr::const_arg_iterator I; |
| ExplodedNode *N; |
| |
| CallExprWLItem(const CallExpr::const_arg_iterator &i, ExplodedNode *n) |
| : I(i), N(n) {} |
| }; |
| } |
| |
| void ExprEngine::evalArguments(ConstExprIterator AI, ConstExprIterator AE, |
| const FunctionProtoType *FnType, |
| ExplodedNode *Pred, ExplodedNodeSet &Dst, |
| bool FstArgAsLValue) { |
| |
| |
| SmallVector<CallExprWLItem, 20> WorkList; |
| WorkList.reserve(AE - AI); |
| WorkList.push_back(CallExprWLItem(AI, Pred)); |
| |
| while (!WorkList.empty()) { |
| CallExprWLItem Item = WorkList.back(); |
| WorkList.pop_back(); |
| |
| if (Item.I == AE) { |
| Dst.insert(Item.N); |
| continue; |
| } |
| |
| // Evaluate the argument. |
| ExplodedNodeSet Tmp; |
| if (FstArgAsLValue) { |
| FstArgAsLValue = false; |
| } |
| |
| Visit(*Item.I, Item.N, Tmp); |
| ++(Item.I); |
| for (ExplodedNodeSet::iterator NI=Tmp.begin(), NE=Tmp.end(); NI != NE; ++NI) |
| WorkList.push_back(CallExprWLItem(Item.I, *NI)); |
| } |
| } |
| |
| void ExprEngine::evalCallee(const CallExpr *callExpr, |
| const ExplodedNodeSet &src, |
| ExplodedNodeSet &dest) { |
| |
| const Expr *callee = 0; |
| |
| switch (callExpr->getStmtClass()) { |
| case Stmt::CXXMemberCallExprClass: { |
| // Evaluate the implicit object argument that is the recipient of the |
| // call. |
| callee = cast<CXXMemberCallExpr>(callExpr)->getImplicitObjectArgument(); |
| |
| // FIXME: handle member pointers. |
| if (!callee) |
| return; |
| |
| break; |
| } |
| default: { |
| callee = callExpr->getCallee()->IgnoreParens(); |
| break; |
| } |
| } |
| |
| for (ExplodedNodeSet::iterator i = src.begin(), e = src.end(); i != e; ++i) |
| Visit(callee, *i, dest); |
| } |
| |
| const CXXThisRegion *ExprEngine::getCXXThisRegion(const CXXRecordDecl *D, |
| const StackFrameContext *SFC) { |
| const Type *T = D->getTypeForDecl(); |
| QualType PT = getContext().getPointerType(QualType(T, 0)); |
| return svalBuilder.getRegionManager().getCXXThisRegion(PT, SFC); |
| } |
| |
| const CXXThisRegion *ExprEngine::getCXXThisRegion(const CXXMethodDecl *decl, |
| const StackFrameContext *frameCtx) { |
| return svalBuilder.getRegionManager(). |
| getCXXThisRegion(decl->getThisType(getContext()), frameCtx); |
| } |
| |
| void ExprEngine::CreateCXXTemporaryObject(const MaterializeTemporaryExpr *ME, |
| ExplodedNode *Pred, |
| ExplodedNodeSet &Dst) { |
| ExplodedNodeSet Tmp; |
| Visit(ME->GetTemporaryExpr(), Pred, Tmp); |
| for (ExplodedNodeSet::iterator I = Tmp.begin(), E = Tmp.end(); I != E; ++I) { |
| const ProgramState *state = (*I)->getState(); |
| |
| // Bind the temporary object to the value of the expression. Then bind |
| // the expression to the location of the object. |
| SVal V = state->getSVal(ME->GetTemporaryExpr()); |
| |
| const MemRegion *R = |
| svalBuilder.getRegionManager().getCXXTempObjectRegion(ME, |
| Pred->getLocationContext()); |
| |
| state = state->bindLoc(loc::MemRegionVal(R), V); |
| MakeNode(Dst, ME, Pred, state->BindExpr(ME, loc::MemRegionVal(R))); |
| } |
| } |
| |
| void ExprEngine::VisitCXXConstructExpr(const CXXConstructExpr *E, |
| const MemRegion *Dest, |
| ExplodedNode *Pred, |
| ExplodedNodeSet &destNodes) { |
| |
| const CXXConstructorDecl *CD = E->getConstructor(); |
| assert(CD); |
| |
| #if 0 |
| if (!(CD->doesThisDeclarationHaveABody() && AMgr.shouldInlineCall())) |
| // FIXME: invalidate the object. |
| return; |
| #endif |
| |
| // Evaluate other arguments. |
| ExplodedNodeSet argsEvaluated; |
| const FunctionProtoType *FnType = CD->getType()->getAs<FunctionProtoType>(); |
| evalArguments(E->arg_begin(), E->arg_end(), FnType, Pred, argsEvaluated); |
| |
| #if 0 |
| // Is the constructor elidable? |
| if (E->isElidable()) { |
| VisitAggExpr(E->getArg(0), destNodes, Pred, Dst); |
| // FIXME: this is here to force propagation if VisitAggExpr doesn't |
| if (destNodes.empty()) |
| destNodes.Add(Pred); |
| return; |
| } |
| #endif |
| |
| // Perform the previsit of the constructor. |
| ExplodedNodeSet destPreVisit; |
| getCheckerManager().runCheckersForPreStmt(destPreVisit, argsEvaluated, E, |
| *this); |
| |
| // Evaluate the constructor. Currently we don't now allow checker-specific |
| // implementations of specific constructors (as we do with ordinary |
| // function calls. We can re-evaluate this in the future. |
| |
| #if 0 |
| // Inlining currently isn't fully implemented. |
| |
| if (AMgr.shouldInlineCall()) { |
| if (!Dest) |
| Dest = |
| svalBuilder.getRegionManager().getCXXTempObjectRegion(E, |
| Pred->getLocationContext()); |
| |
| // The callee stack frame context used to create the 'this' |
| // parameter region. |
| const StackFrameContext *SFC = |
| AMgr.getStackFrame(CD, Pred->getLocationContext(), |
| E, Builder->getBlock(), Builder->getIndex()); |
| |
| // Create the 'this' region. |
| const CXXThisRegion *ThisR = |
| getCXXThisRegion(E->getConstructor()->getParent(), SFC); |
| |
| CallEnter Loc(E, SFC, Pred->getLocationContext()); |
| |
| |
| for (ExplodedNodeSet::iterator NI = argsEvaluated.begin(), |
| NE = argsEvaluated.end(); NI != NE; ++NI) { |
| const ProgramState *state = (*NI)->getState(); |
| // Setup 'this' region, so that the ctor is evaluated on the object pointed |
| // by 'Dest'. |
| state = state->bindLoc(loc::MemRegionVal(ThisR), loc::MemRegionVal(Dest)); |
| if (ExplodedNode *N = Builder->generateNode(Loc, state, *NI)) |
| destNodes.Add(N); |
| } |
| } |
| #endif |
| |
| // Default semantics: invalidate all regions passed as arguments. |
| SmallVector<const MemRegion*, 10> regionsToInvalidate; |
| |
| // FIXME: We can have collisions on the conjured symbol if the |
| // expression *I also creates conjured symbols. We probably want |
| // to identify conjured symbols by an expression pair: the enclosing |
| // expression (the context) and the expression itself. This should |
| // disambiguate conjured symbols. |
| unsigned blockCount = Builder->getCurrentBlockCount(); |
| |
| // NOTE: Even if RegionsToInvalidate is empty, we must still invalidate |
| // global variables. |
| ExplodedNodeSet destCall; |
| |
| for (ExplodedNodeSet::iterator |
| i = destPreVisit.begin(), e = destPreVisit.end(); |
| i != e; ++i) |
| { |
| ExplodedNode *Pred = *i; |
| const ProgramState *state = Pred->getState(); |
| |
| // Accumulate list of regions that are invalidated. |
| for (CXXConstructExpr::const_arg_iterator |
| ai = E->arg_begin(), ae = E->arg_end(); |
| ai != ae; ++ai) |
| { |
| SVal val = state->getSVal(*ai); |
| if (const MemRegion *region = val.getAsRegion()) |
| regionsToInvalidate.push_back(region); |
| } |
| |
| // Invalidate the regions. |
| state = state->invalidateRegions(regionsToInvalidate.data(), |
| regionsToInvalidate.data() + |
| regionsToInvalidate.size(), |
| E, blockCount, 0, |
| /* invalidateGlobals = */ true); |
| |
| Builder->MakeNode(destCall, E, Pred, state); |
| } |
| |
| // Do the post visit. |
| getCheckerManager().runCheckersForPostStmt(destNodes, destCall, E, *this); |
| } |
| |
| void ExprEngine::VisitCXXDestructor(const CXXDestructorDecl *DD, |
| const MemRegion *Dest, |
| const Stmt *S, |
| ExplodedNode *Pred, |
| ExplodedNodeSet &Dst) { |
| if (!(DD->doesThisDeclarationHaveABody() && AMgr.shouldInlineCall())) |
| return; |
| // Create the context for 'this' region. |
| const StackFrameContext *SFC = AMgr.getStackFrame(DD, |
| Pred->getLocationContext(), |
| S, Builder->getBlock(), |
| Builder->getIndex()); |
| |
| const CXXThisRegion *ThisR = getCXXThisRegion(DD->getParent(), SFC); |
| |
| CallEnter PP(S, SFC, Pred->getLocationContext()); |
| |
| const ProgramState *state = Pred->getState(); |
| state = state->bindLoc(loc::MemRegionVal(ThisR), loc::MemRegionVal(Dest)); |
| ExplodedNode *N = Builder->generateNode(PP, state, Pred); |
| if (N) |
| Dst.Add(N); |
| } |
| |
| void ExprEngine::VisitCXXNewExpr(const CXXNewExpr *CNE, ExplodedNode *Pred, |
| ExplodedNodeSet &Dst) { |
| |
| unsigned blockCount = Builder->getCurrentBlockCount(); |
| DefinedOrUnknownSVal symVal = |
| svalBuilder.getConjuredSymbolVal(NULL, CNE, CNE->getType(), blockCount); |
| const MemRegion *NewReg = cast<loc::MemRegionVal>(symVal).getRegion(); |
| QualType ObjTy = CNE->getType()->getAs<PointerType>()->getPointeeType(); |
| const ElementRegion *EleReg = |
| getStoreManager().GetElementZeroRegion(NewReg, ObjTy); |
| |
| if (CNE->isArray()) { |
| // FIXME: allocating an array requires simulating the constructors. |
| // For now, just return a symbolicated region. |
| const ProgramState *state = Pred->getState(); |
| state = state->BindExpr(CNE, loc::MemRegionVal(EleReg)); |
| MakeNode(Dst, CNE, Pred, state); |
| return; |
| } |
| |
| // Evaluate constructor arguments. |
| const FunctionProtoType *FnType = NULL; |
| const CXXConstructorDecl *CD = CNE->getConstructor(); |
| if (CD) |
| FnType = CD->getType()->getAs<FunctionProtoType>(); |
| ExplodedNodeSet argsEvaluated; |
| evalArguments(CNE->constructor_arg_begin(), CNE->constructor_arg_end(), |
| FnType, Pred, argsEvaluated); |
| |
| // Initialize the object region and bind the 'new' expression. |
| for (ExplodedNodeSet::iterator I = argsEvaluated.begin(), |
| E = argsEvaluated.end(); I != E; ++I) { |
| |
| const ProgramState *state = (*I)->getState(); |
| |
| // Accumulate list of regions that are invalidated. |
| // FIXME: Eventually we should unify the logic for constructor |
| // processing in one place. |
| SmallVector<const MemRegion*, 10> regionsToInvalidate; |
| for (CXXNewExpr::const_arg_iterator |
| ai = CNE->constructor_arg_begin(), ae = CNE->constructor_arg_end(); |
| ai != ae; ++ai) |
| { |
| SVal val = state->getSVal(*ai); |
| if (const MemRegion *region = val.getAsRegion()) |
| regionsToInvalidate.push_back(region); |
| } |
| |
| if (ObjTy->isRecordType()) { |
| regionsToInvalidate.push_back(EleReg); |
| // Invalidate the regions. |
| state = state->invalidateRegions(regionsToInvalidate.data(), |
| regionsToInvalidate.data() + |
| regionsToInvalidate.size(), |
| CNE, blockCount, 0, |
| /* invalidateGlobals = */ true); |
| |
| } else { |
| // Invalidate the regions. |
| state = state->invalidateRegions(regionsToInvalidate.data(), |
| regionsToInvalidate.data() + |
| regionsToInvalidate.size(), |
| CNE, blockCount, 0, |
| /* invalidateGlobals = */ true); |
| |
| if (CNE->hasInitializer()) { |
| SVal V = state->getSVal(*CNE->constructor_arg_begin()); |
| state = state->bindLoc(loc::MemRegionVal(EleReg), V); |
| } else { |
| // Explicitly set to undefined, because currently we retrieve symbolic |
| // value from symbolic region. |
| state = state->bindLoc(loc::MemRegionVal(EleReg), UndefinedVal()); |
| } |
| } |
| state = state->BindExpr(CNE, loc::MemRegionVal(EleReg)); |
| MakeNode(Dst, CNE, *I, state); |
| } |
| } |
| |
| void ExprEngine::VisitCXXDeleteExpr(const CXXDeleteExpr *CDE, |
| ExplodedNode *Pred,ExplodedNodeSet &Dst) { |
| // Should do more checking. |
| ExplodedNodeSet Argevaluated; |
| Visit(CDE->getArgument(), Pred, Argevaluated); |
| for (ExplodedNodeSet::iterator I = Argevaluated.begin(), |
| E = Argevaluated.end(); I != E; ++I) { |
| const ProgramState *state = (*I)->getState(); |
| MakeNode(Dst, CDE, *I, state); |
| } |
| } |
| |
| void ExprEngine::VisitCXXThisExpr(const CXXThisExpr *TE, ExplodedNode *Pred, |
| ExplodedNodeSet &Dst) { |
| // Get the this object region from StoreManager. |
| const MemRegion *R = |
| svalBuilder.getRegionManager().getCXXThisRegion( |
| getContext().getCanonicalType(TE->getType()), |
| Pred->getLocationContext()); |
| |
| const ProgramState *state = Pred->getState(); |
| SVal V = state->getSVal(loc::MemRegionVal(R)); |
| MakeNode(Dst, TE, Pred, state->BindExpr(TE, V)); |
| } |