RFR: relax pattern matching for CAS on aarch64

[Aleksey Shipilev]

On 10/13/2017 02:37 PM, Aleksey Shipilev wrote:
> On 10/13/2017 02:13 PM, Roland Westrelin wrote:
>>
>> http://cr.openjdk.java.net/~roland/shenandoah/caspatternmatching/webrev.00/
> 
> Ugh! This does not look obviously idempotent if !UseShenandoahGC. Let's think how to minimize the
> change. Let me try a thing...

How about this?
  http://cr.openjdk.java.net/~shade/shenandoah/cas-pattern-matching/webrev.01/

(the hotspot.changeset there has a diff against your current patch)

I haven't tested it.

Thanks,
-Aleksey