/// DeclareGlobalAllocationFunction - Declares a single implicit global
/// allocation function if it doesn't already exist.
void Sema::DeclareGlobalAllocationFunction(DeclarationName Name,
QualType Return, QualType Argument)
{
DeclContext *GlobalCtx = Context.getTranslationUnitDecl();
// Check if this function is already declared.
{
DeclContext::lookup_iterator Alloc, AllocEnd;
for (llvm::tie(Alloc, AllocEnd) = GlobalCtx->lookup(Context, Name);
Alloc != AllocEnd; ++Alloc) {
// FIXME: Do we need to check for default arguments here?
FunctionDecl *Func = cast<FunctionDecl>(*Alloc);
if (Func->getNumParams() == 1 &&
Context.getCanonicalType(Func->getParamDecl(0)->getType())==Argument)
return;
}
}
QualType FnType = Context.getFunctionType(Return, &Argument, 1, false, 0);
FunctionDecl *Alloc =
FunctionDecl::Create(Context, GlobalCtx, SourceLocation(), Name,
FnType, FunctionDecl::None, false, true,
SourceLocation());
Alloc->setImplicit();
ParmVarDecl *Param = ParmVarDecl::Create(Context, Alloc, SourceLocation(),
0, Argument, VarDecl::None, 0);
Alloc->setParams(Context, &Param, 1);
// FIXME: Also add this declaration to the IdentifierResolver, but
// make sure it is at the end of the chain to coincide with the
// global scope.
((DeclContext *)TUScope->getEntity())->addDecl(Context, Alloc);
}
void SimpleInliner::generateParamStrings(void)
{
unsigned int ArgNum = TheCallExpr->getNumArgs();
FunctionDecl *FD = TheCallExpr->getDirectCallee();
unsigned int Idx;
for(Idx = 0; Idx < FD->getNumParams(); ++Idx) {
const ParmVarDecl *PD = FD->getParamDecl(Idx);
std::string ParmStr = PD->getNameAsString();
PD->getType().getAsStringInternal(ParmStr,
Context->getPrintingPolicy());
if (Idx < ArgNum) {
const Expr *Arg = TheCallExpr->getArg(Idx);
ParmStr += " = ";
std::string ArgStr("");
RewriteHelper->getExprString(Arg, ArgStr);
ParmStr += ArgStr;
}
ParmStr += ";\n";
ParmStrings.push_back(ParmStr);
}
}
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);
}
}
}
