Release store in C2 putfield

Andrew Haley aph at
Fri Sep 5 14:41:25 UTC 2014

On 09/05/2014 03:35 PM, Doug Lea wrote:
> ARMv8 (also IA64) acquire/release specs bind some effects
> to the locations. If you treat the release and store
> as separable, and later combine at instruction generation, it's
> superficially conceivable that you'd lose something in case you
> matched different writes with different fences. (Plus, if you
> cannot combine, you'd choose a plain fence or use fake thread-local
> target for releasing write; although we've seen (for x86) that
> choosing fake targets can be challenging...)

I think I may give up even trying to combine fences with writes, and
emit explicit barrier instructions.  That way I at least don't lose
relative to other targets.


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