RFR: 8179387: Factor out CMS specific code from GenCollectedHeap into its own subclass

[Roman Kennke]

Take this patch. It #ifdef ASSERT's a call to check_gen_kinds() that is
only present in debug builds.


http://cr.openjdk.java.net/~rkennke/8179387/webrev.01/
<http://cr.openjdk.java.net/%7Erkennke/8179387/webrev.01/>

Roman

Am 01.06.2017 um 22:50 schrieb Roman Kennke:
> What $SUBJECT says.
>
> I went over genCollectedHeap.[hpp|cpp] and moved everything that I could
> find that is CMS-only into a new CMSHeap class.
>
> http://cr.openjdk.java.net/~rkennke/8179387/webrev.00/
> <http://cr.openjdk.java.net/%7Erkennke/8179387/webrev.00/>
>
> It is possible that I overlooked something there. There may be code in
> there that doesn't shout "CMS" at me, but is still intrinsically CMS stuff.
>
> Also not that I have not removed that little part:
>
>   always_do_update_barrier = UseConcMarkSweepGC;
>
> because I expect it to go away with Erik Ö's big refactoring.
>
> What do you think?
>
> Testing: hotspot_gc, specjvm, some little apps with -XX:+UseConcMarkSweepGC
>
> Roman
>