RuntimeDefinition CXXInstanceCall::getRuntimeDefinition() const {
// Do we have a decl at all?
const Decl *D = getDecl();
if (!D)
return RuntimeDefinition();
// If the method is non-virtual, we know we can inline it.
const CXXMethodDecl *MD = cast<CXXMethodDecl>(D);
if (!MD->isVirtual())
return AnyFunctionCall::getRuntimeDefinition();
// Do we know the implicit 'this' object being called?
const MemRegion *R = getCXXThisVal().getAsRegion();
if (!R)
return RuntimeDefinition();
// Do we know anything about the type of 'this'?
DynamicTypeInfo DynType = getState()->getDynamicTypeInfo(R);
if (!DynType.isValid())
return RuntimeDefinition();
// Is the type a C++ class? (This is mostly a defensive check.)
QualType RegionType = DynType.getType()->getPointeeType();
assert(!RegionType.isNull() && "DynamicTypeInfo should always be a pointer.");
const CXXRecordDecl *RD = RegionType->getAsCXXRecordDecl();
if (!RD || !RD->hasDefinition())
return RuntimeDefinition();
// Find the decl for this method in that class.
const CXXMethodDecl *Result = MD->getCorrespondingMethodInClass(RD, true);
if (!Result) {
// We might not even get the original statically-resolved method due to
// some particularly nasty casting (e.g. casts to sister classes).
// However, we should at least be able to search up and down our own class
// hierarchy, and some real bugs have been caught by checking this.
assert(!RD->isDerivedFrom(MD->getParent()) && "Couldn't find known method");
// FIXME: This is checking that our DynamicTypeInfo is at least as good as
// the static type. However, because we currently don't update
// DynamicTypeInfo when an object is cast, we can't actually be sure the
// DynamicTypeInfo is up to date. This assert should be re-enabled once
// this is fixed. <rdar://problem/12287087>
//assert(!MD->getParent()->isDerivedFrom(RD) && "Bad DynamicTypeInfo");
return RuntimeDefinition();
}
// Does the decl that we found have an implementation?
const FunctionDecl *Definition;
if (!Result->hasBody(Definition))
return RuntimeDefinition();
// We found a definition. If we're not sure that this devirtualization is
// actually what will happen at runtime, make sure to provide the region so
// that ExprEngine can decide what to do with it.
if (DynType.canBeASubClass())
return RuntimeDefinition(Definition, R->StripCasts());
return RuntimeDefinition(Definition, /*DispatchRegion=*/0);
}
RuntimeDefinition ObjCMethodCall::getRuntimeDefinition() const {
const ObjCMessageExpr *E = getOriginExpr();
assert(E);
Selector Sel = E->getSelector();
if (E->isInstanceMessage()) {
// Find the the receiver type.
const ObjCObjectPointerType *ReceiverT = 0;
bool CanBeSubClassed = false;
QualType SupersType = E->getSuperType();
const MemRegion *Receiver = 0;
if (!SupersType.isNull()) {
// Super always means the type of immediate predecessor to the method
// where the call occurs.
ReceiverT = cast<ObjCObjectPointerType>(SupersType);
} else {
Receiver = getReceiverSVal().getAsRegion();
if (!Receiver)
return RuntimeDefinition();
DynamicTypeInfo DTI = getState()->getDynamicTypeInfo(Receiver);
QualType DynType = DTI.getType();
CanBeSubClassed = DTI.canBeASubClass();
ReceiverT = dyn_cast<ObjCObjectPointerType>(DynType);
if (ReceiverT && CanBeSubClassed)
if (ObjCInterfaceDecl *IDecl = ReceiverT->getInterfaceDecl())
if (!canBeOverridenInSubclass(IDecl, Sel))
CanBeSubClassed = false;
}
// Lookup the method implementation.
if (ReceiverT)
if (ObjCInterfaceDecl *IDecl = ReceiverT->getInterfaceDecl()) {
const ObjCMethodDecl *MD = IDecl->lookupPrivateMethod(Sel);
if (CanBeSubClassed)
return RuntimeDefinition(MD, Receiver);
else
return RuntimeDefinition(MD, 0);
}
} else {
// This is a class method.
// If we have type info for the receiver class, we are calling via
// class name.
if (ObjCInterfaceDecl *IDecl = E->getReceiverInterface()) {
// Find/Return the method implementation.
return RuntimeDefinition(IDecl->lookupPrivateClassMethod(Sel));
}
}
return RuntimeDefinition();
}
RuntimeDefinition CXXInstanceCall::getRuntimeDefinition() const {
// Do we have a decl at all?
const Decl *D = getDecl();
if (!D)
return RuntimeDefinition();
// If the method is non-virtual, we know we can inline it.
const CXXMethodDecl *MD = cast<CXXMethodDecl>(D);
if (!MD->isVirtual())
return AnyFunctionCall::getRuntimeDefinition();
// Do we know the implicit 'this' object being called?
const MemRegion *R = getCXXThisVal().getAsRegion();
if (!R)
return RuntimeDefinition();
// Do we know anything about the type of 'this'?
DynamicTypeInfo DynType = getState()->getDynamicTypeInfo(R);
if (!DynType.isValid())
return RuntimeDefinition();
// Is the type a C++ class? (This is mostly a defensive check.)
QualType RegionType = DynType.getType()->getPointeeType();
const CXXRecordDecl *RD = RegionType->getAsCXXRecordDecl();
if (!RD || !RD->hasDefinition())
return RuntimeDefinition();
// Find the decl for this method in that class.
const CXXMethodDecl *Result = MD->getCorrespondingMethodInClass(RD, true);
assert(Result && "At the very least the static decl should show up.");
// Does the decl that we found have an implementation?
const FunctionDecl *Definition;
if (!Result->hasBody(Definition))
return RuntimeDefinition();
// We found a definition. If we're not sure that this devirtualization is
// actually what will happen at runtime, make sure to provide the region so
// that ExprEngine can decide what to do with it.
if (DynType.canBeASubClass())
return RuntimeDefinition(Definition, R->StripCasts());
return RuntimeDefinition(Definition, /*DispatchRegion=*/0);
}
RuntimeDefinition ObjCMethodCall::getRuntimeDefinition() const {
const ObjCMessageExpr *E = getOriginExpr();
assert(E);
Selector Sel = E->getSelector();
if (E->isInstanceMessage()) {
// Find the the receiver type.
const ObjCObjectPointerType *ReceiverT = 0;
bool CanBeSubClassed = false;
QualType SupersType = E->getSuperType();
const MemRegion *Receiver = 0;
if (!SupersType.isNull()) {
// Super always means the type of immediate predecessor to the method
// where the call occurs.
ReceiverT = cast<ObjCObjectPointerType>(SupersType);
} else {
Receiver = getReceiverSVal().getAsRegion();
if (!Receiver)
return RuntimeDefinition();
DynamicTypeInfo DTI = getState()->getDynamicTypeInfo(Receiver);
QualType DynType = DTI.getType();
CanBeSubClassed = DTI.canBeASubClass();
ReceiverT = dyn_cast<ObjCObjectPointerType>(DynType);
if (ReceiverT && CanBeSubClassed)
if (ObjCInterfaceDecl *IDecl = ReceiverT->getInterfaceDecl())
if (!canBeOverridenInSubclass(IDecl, Sel))
CanBeSubClassed = false;
}
// Lookup the method implementation.
if (ReceiverT)
if (ObjCInterfaceDecl *IDecl = ReceiverT->getInterfaceDecl()) {
// Repeatedly calling lookupPrivateMethod() is expensive, especially
// when in many cases it returns null. We cache the results so
// that repeated queries on the same ObjCIntefaceDecl and Selector
// don't incur the same cost. On some test cases, we can see the
// same query being issued thousands of times.
//
// NOTE: This cache is essentially a "global" variable, but it
// only gets lazily created when we get here. The value of the
// cache probably comes from it being global across ExprEngines,
// where the same queries may get issued. If we are worried about
// concurrency, or possibly loading/unloading ASTs, etc., we may
// need to revisit this someday. In terms of memory, this table
// stays around until clang quits, which also may be bad if we
// need to release memory.
typedef std::pair<const ObjCInterfaceDecl*, Selector>
PrivateMethodKey;
typedef llvm::DenseMap<PrivateMethodKey,
Optional<const ObjCMethodDecl *> >
PrivateMethodCache;
static PrivateMethodCache PMC;
Optional<const ObjCMethodDecl *> &Val = PMC[std::make_pair(IDecl, Sel)];
// Query lookupPrivateMethod() if the cache does not hit.
if (!Val.hasValue())
Val = IDecl->lookupPrivateMethod(Sel);
const ObjCMethodDecl *MD = Val.getValue();
if (CanBeSubClassed)
return RuntimeDefinition(MD, Receiver);
else
return RuntimeDefinition(MD, 0);
}
} else {
// This is a class method.
// If we have type info for the receiver class, we are calling via
// class name.
if (ObjCInterfaceDecl *IDecl = E->getReceiverInterface()) {
// Find/Return the method implementation.
return RuntimeDefinition(IDecl->lookupPrivateClassMethod(Sel));
}
}
return RuntimeDefinition();
}
