Enable optimization of arraycopy as loads/stores with Shenandoah

[Roman Kennke]

Am Donnerstag, den 08.12.2016, 17:14 +0100 schrieb Roland Westrelin:
> > Now that you say it, I wonder what's done for other GCs. They must
> > be
> > doing something here, to update the card tables. Other arraycopy
> > routines call a special barrier in
> > BarrierSet::static_write_ref_array_post(), this is not suitable for
> > clones, but do they call any barrier for clone too? Or can other
> > GCs
> > ignore it because it's basically initializing stores?
> 
> For clone, unless ReduceInitialCardMarks is false, nothing is done
> AFAICT.

Ok. And what happens when ReduceInitialCardMarks is false? Because this
might be what we need.

Roman