[sh/jdk11u]: JVMTI related backports

[Zhengyu Gu]

Hi Aleksey,

Lost your reply in inbox somehow.

 > If we want to cherry-pick 8237396 ahead of 11u, we have to protect it 
 > with UseShenandoahGC. I think
 > like this:

I will wait jdk11u backport to arrive, so hold off this backport.

Thanks,

-Zhengyu


On 2/28/20 4:37 PM, Zhengyu Gu wrote:
> I would like to backport these two JVMTI heap walk related backports:
> 
> 8237396: JvmtiTagMap::weak_oops_do() should not trigger barriers
> 8237632: Shenandoah: accept NULL fwdptr to cooperate with JVMTI and JFR
> 
> The backports clear JVMTI related test failures.
> 
> Webrev: 
> http://cr.openjdk.java.net/~zgu/shenandoah/jvmti_sh_jdk11u/webrev.00/
> 
> Test:
>    hotspot_gc_shenandoah
>    vmTestbase_nsk_jvmti
>    vmTestbase_nsk_jdi
> 
> Thanks,
> 
> -Zhengyu
> 
>