/**
* Given a slot (ie the address of an ObjectReference), ensure that the referent will not move for
* the rest of the GC. This is achieved by calling the precopyObject method.
*
* @param slot The slot to check
*/
@Inline
public final void processPrecopyEdge(Address slot) {
ObjectReference child = slot.loadObjectReference();
if (!child.isNull()) {
child = precopyObject(child);
slot.store(child);
}
}
/**
* Trace a reference during GC. This involves determining which collection policy applies and
* calling the appropriate <code>trace</code> method.
*
* @param target The object the interior edge points within.
* @param slot The location of the interior edge.
* @param root True if this is a root edge.
*/
public final void processInteriorEdge(ObjectReference target, Address slot, boolean root) {
Address interiorRef = slot.loadAddress();
Offset offset = interiorRef.diff(target.toAddress());
ObjectReference newTarget = traceObject(target, root);
if (VM.VERIFY_ASSERTIONS) {
if (offset.sLT(Offset.zero()) || offset.sGT(Offset.fromIntSignExtend(1 << 24))) {
// There is probably no object this large
Log.writeln("ERROR: Suspiciously large delta to interior pointer");
Log.write(" object base = ");
Log.writeln(target);
Log.write(" interior reference = ");
Log.writeln(interiorRef);
Log.write(" delta = ");
Log.writeln(offset);
VM.assertions._assert(false);
}
}
slot.store(newTarget.toAddress().plus(offset));
}
/**
* Trace a reference during GC. This involves determining which collection policy applies and
* calling the appropriate <code>trace</code> method.
*
* @param source The source of the reference.
* @param slot The location containing the object reference to be traced. The object reference is
* <i>NOT</i> an interior pointer.
* @param root True if <code>objLoc</code> is within a root.
*/
@Inline
public final void processEdge(ObjectReference source, Address slot) {
ObjectReference object = slot.loadObjectReference();
ObjectReference newObject = traceObject(object, false);
slot.store(newObject);
}
/**
* Trace a reference during GC. This involves determining which collection policy applies and
* calling the appropriate <code>trace</code> method.
*
* @param slot The location containing the object reference to be traced. The object reference is
* <i>NOT</i> an interior pointer.
* @param root True if <code>objLoc</code> is within a root.
*/
@Inline
public final void processRootEdge(Address slot) {
ObjectReference object = slot.loadObjectReference();
ObjectReference newObject = traceObject(object, true);
slot.store(newObject);
}
