[aarch64-port-dev ] RFR (XS) 8252366: Shenandoah: revert/cleanup changes in graphKit.cpp

[Andrew Hughes]

On 13:08 Wed 26 Aug     , Aleksey Shipilev wrote:
> On 8/26/20 1:01 PM, Roland Westrelin wrote:
> > > It looks like this is not actually used for reference types. The only
> > > uses are in library_call.cpp and they don't look like they ever load a
> > > reference. Please check and confirm to be sure.
> > 
> > It does on PPC. In LibraryCallKit::get_key_start_from_aescrypt_object().
> 
> Yes. I misjudged the assert: it actually verifies the current Shenandoah
> uses do not need the LRB there. Shenandoah is not supported (yet) on PPC, so
> there is no bug yet, and assert is just too strong for PPC code. But it
> feels more future proof just to insert the Shenandoah barrier there.
> 
> 8u webrev:
>  https://cr.openjdk.java.net/~shade/8252366/webrev.02/
> 
> Testing: hotspot_gc_shenandoah {fastdebug,release}
> 
> -- 
> Thanks,
> -Aleksey
> 

Looks ok to me. Not having a g1_write_barrier_pre_helper function
which is actually Shenandoah-only should add a little clarity :-)

Thanks,
-- 
Andrew :)

Senior Free Java Software Engineer
OpenJDK Package Owner
Red Hat, Inc. (http://www.redhat.com)

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