RFR 8232010: Shenandoah: implement self-fixing native barrier

[Roman Kennke]

Would a similar implementation also work for the non-native LRB?

It's lacking an aarch64 implementation, right?

Roman


> Please review this patch that implements self-fixing LRB for in native
> oops.
> 
> Bug: https://bugs.openjdk.java.net/browse/JDK-8232010
> Webrev: http://cr.openjdk.java.net/~zgu/JDK-8232010/webrev.00/
> 
> Test:
>   hotspot_gc_shenandoah (fastdebug and release) with x86_32 and x86_64
> JVM on Linux.
> 
> Thanks,
> 
> -Zhengyu
>