RFR: Shenandoah: Isolate changes around BarrierSetC2::enqueue_useful_gc_barrier()

[Roman Kennke]

Roland Westrelin <rwestrel at redhat.com> schrieb am Mi., 8. Juli 2020, 09:12:

>
> >
> http://cr.openjdk.java.net/~rkennke/shjdk11-c2-enqueue-barrier/webrev.00/
>
> Why enqueue the uses of the uses as well?
>
>  924     for (DUIterator_Fast imax, i = node->fast_outs(imax); i < imax;
> i++) {
>  925       Node* use = node->fast_out(i); // Get use
>  926       add_users_to_worklist0(worklist, use);
>  927     }
>

As far as I can tell, that's what the previous call to
PhaseIGVN::add_users_to_worklist() did for CallLeafNodes there, I tried to
mimic that. Do you agree?

Thanks, Roman

>
> Roland.
>
>