RFR: (sh/jdk11): Bulk backports 2020-03-03

[Aleksey Shipilev]

On 3/3/20 7:38 PM, Aleksey Shipilev wrote:
> On 3/3/20 7:37 PM, Roman Kennke wrote:
>>> *) Do we really need 8238574? Notice in the original changeset it checks the result of LRB_native:
>>>   https://hg.openjdk.java.net/jdk/jdk/rev/8d8916159b62
>>>  ...is it even possible with non-native LRB in 11u?
>>
>> This is a bit strange. It *is* the native (runtime) barrier in sh/11.
>> However, it's pretty useless because we don't do any concurrent roots
>> processing. No, I don't think the NULL can actually happen because we
>> process all roots at the pause. What should I do? Get rid of the change?
>> Get rid of the whole runtime native barriers?
> 
> Since filtering NULL there is harmless now (and may stop being harmless in future, *if* we ever
> decide to backport native stuff), I believe having that null check there is the best course of action.

Meant to say: "[the absence of the null-check] may stop being harmless in future, *if* we ever
decide to backport native stuff". Better be safe than sorry here.

-- 
Thanks,
-Aleksey