RFR(sh/jdk8): [backport] 8231087: Shenandoah: Self-fixing load reference barriers for C1/C2

[Roman Kennke]

Rebased on previous changes. Please review this instead:

http://cr.openjdk.java.net/~rkennke/JDK-8231087-jdk8/webrev.03/

Thanks,
Roman

On 24/11/2020 17:11, Roman Kennke wrote:
> I made a mistake in the aarch64 parts. Please review this webrev instead:
> 
> http://cr.openjdk.java.net/~rkennke/JDK-8231087-jdk8/webrev.02/
> 
>> 2nd attempt:
>>
>> Issue:
>> https://bugs.openjdk.java.net/browse/JDK-8231087
>>
>> Backport:
>> http://cr.openjdk.java.net/~rkennke/JDK-8231087-jdk8/webrev.01/
>>
>> This time includes the actual C1 stuff (depended on JDK-8228369).
>>
>> Let's include a few follow-ups:
>>
>> https://bugs.openjdk.java.net/browse/JDK-8233165
>> http://cr.openjdk.java.net/~rkennke/JDK-8233165-jdk8/webrev.00/
>>
>> and
>>
>> https://bugs.openjdk.java.net/browse/JDK-8233021
>> http://cr.openjdk.java.net/~rkennke/JDK-8233021-jdk8/webrev.00/
>>
>> and
>>
>> https://bugs.openjdk.java.net/browse/JDK-8238153
>> http://cr.openjdk.java.net/~rkennke/JDK-8238153-jdk8/webrev.00/
>>
>> Can I please get a review?
>>
>> Thanks,
>> Roman