RFR(S): 8087341: C2 doesn't optimize redundant memory operations with G1

[Roland Westrelin]

Hi Andrew,

> This patch breaks the AArch64 C2 code to optimize volatile stores for
> the expected cases:
> 
>  1) +G1GC
>  2) +ConcMarkSweepGC + CondCardMark
> 
> I believe it can be fixed but I have not yet identified the required
> code changes.

Thanks for the update. I’ll wait to hear back from you before I get this in.

Roland.