RFR 8201785: Make ModRefBarrierSetAssembler abstract on all platforms

[Aleksey Shipilev]

On 04/19/2018 10:32 AM, Per Liden wrote:
> Looks good to me!
> 
> /Per
> 
> On 04/18/2018 01:57 PM, Aleksey Shipilev wrote:
>> RFE:
>>    https://bugs.openjdk.java.net/browse/JDK-8201785
>>
>> Webrev:
>>    http://cr.openjdk.java.net/~shade/8201785/webrev.02/
>>
>> Found this when while rebasing Epsilon to the recent jdk/jdk. ModRefBSAssembler is abstract on some
>> platforms (x86, sparc), but not on the others (aarch64, ppc). I think this allows missing the
>> required overrides of oop_store_at in ModRefBSAssembler subclasses, which should be caught
>> mechanically. (Epsilon used to defer to ModRefBSAssembler, and it was successfully instantiated!)
>>
>> PPC folks, would you like to give it a spin on your platforms?

Thanks, Per. Thomas S, Martin D, do you trust me with PPC here? :)

-Aleksey