RFR(S): Implementation of aarch64 interpreter matrix barrier

[Aleksey Shipilev]

On 06/21/2017 04:51 PM, Zhengyu Gu wrote:
> Thanks for the review, Andrew and Aleksey,
> 
> I updated patch according to your comments:
> 
> Webrev:
> http://cr.openjdk.java.net/~zgu/shenandoah/aarch64_int_matrix_barrier/webrev.01/

*) This line smells odd:

3880   unsigned long offset;
3881   adrp(rscratch2, ExternalAddress(ShenandoahHeap::heap()->base()), offset);

...is that ExternalAddress(...base(), (unsigned long)0)?

Otherwise seems fine.

-Aleksey