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::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.
unsigned blockCount = currBldrCtx->blockCount();
const LocationContext *LCtx = Pred->getLocationContext();
DefinedOrUnknownSVal symVal = UnknownVal();
FunctionDecl *FD = CNE->getOperatorNew();
bool IsStandardGlobalOpNewFunction = false;
if (FD && !isa<CXXMethodDecl>(FD) && !FD->isVariadic()) {
if (FD->getNumParams() == 2) {
QualType T = FD->getParamDecl(1)->getType();
if (const IdentifierInfo *II = T.getBaseTypeIdentifier())
// NoThrow placement new behaves as a standard new.
IsStandardGlobalOpNewFunction = II->getName().equals("nothrow_t");
}
else
// Placement forms are considered non-standard.
IsStandardGlobalOpNewFunction = (FD->getNumParams() == 1);
}
// We assume all standard global 'operator new' functions allocate memory in
// heap. We realize this is an approximation that might not correctly model
// a custom global allocator.
if (IsStandardGlobalOpNewFunction)
symVal = svalBuilder.getConjuredHeapSymbolVal(CNE, LCtx, blockCount);
else
symVal = svalBuilder.conjureSymbolVal(nullptr, 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 (!State)
return;
// If this allocation function is not declared as non-throwing, failures
// /must/ be signalled by exceptions, and thus the return value will never be
// NULL. -fno-exceptions does not influence this semantics.
// FIXME: GCC has a -fcheck-new option, which forces it to consider the case
// where new can return NULL. If we end up supporting that option, we can
// consider adding a check for it here.
// C++11 [basic.stc.dynamic.allocation]p3.
if (FD) {
QualType Ty = FD->getType();
if (const FunctionProtoType *ProtoType = Ty->getAs<FunctionProtoType>())
if (!ProtoType->isNothrow(getContext()))
State = State->assume(symVal, true);
}
StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
if (CNE->isArray()) {
// FIXME: allocating an array requires simulating the constructors.
// For now, just return a symbolicated region.
const MemRegion *NewReg = symVal.castAs<loc::MemRegionVal>().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.)
SVal Result = symVal;
if (FD && FD->isReservedGlobalPlacementOperator()) {
// Non-array placement new should always return the placement location.
SVal PlacementLoc = State->getSVal(CNE->getPlacementArg(0), LCtx);
Result = svalBuilder.evalCast(PlacementLoc, CNE->getType(),
CNE->getPlacementArg(0)->getType());
}
// Bind the address of the object, then check to see if we cached out.
State = State->BindExpr(CNE, LCtx, Result);
ExplodedNode *NewN = Bldr.generateNode(CNE, Pred, State);
if (!NewN)
return;
// 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)) {
assert(Bldr.getResults().size() == 1);
Bldr.takeNodes(NewN);
evalBind(Dst, CNE, NewN, Result, State->getSVal(Init, LCtx),
/*FirstInit=*/IsStandardGlobalOpNewFunction);
}
}
}