public OopHandle getOopHandle(int x) {
Address oopAddr = getOopHandleAddress(x);
if (oopAddr != null) {
return oopAddr.getOopHandleAt(0);
}
return null;
}
public void visitAddress(Address addr) {
Oop next = heap.newOop(addr.getOopHandleAt(0));
LivenessPathElement lp =
new LivenessPathElement(
null, new NamedFieldIdentifier(baseRootDescription + " @ " + addr));
rp.put(lp, next);
markAndTraverse(next);
}
/** Only returns addresses of valid OopHandles */
private Address getOopHandleAddress(int x) {
if (Assert.ASSERTS_ENABLED) {
Assert.that(x < top(), "out of bounds");
}
Address oopAddr = addr.addOffsetTo(handlesField.getOffset() + x * VM.getVM().getOopSize());
OopHandle handle = oopAddr.getOopHandleAt(0);
if (VM.getVM().getUniverse().isInReserved(handle)
&& !VM.getVM().getJNIHandles().isDeletedHandle(handle)) {
/* the oop handle is valid only if it is not freed (i.e. reserved in heap) and is not a deleted oop */
return oopAddr;
} else {
return null;
}
}