RFR: 8186670: Implement _onSpinWait() intrinsic for AArch64

[Evgeny Astigeevich]

On Fri, 17 Sep 2021 17:44:07 GMT, Paul Hohensee <phh at openjdk.org> wrote:

> Do you intend to make isb the default for N1?

Yes, I do.
I'll rewrite https://github.com/openjdk/jdk/pull/5112 to use different implementations.
After that, I'd like to enable it for N1.

-------------

PR: https://git.openjdk.java.net/jdk/pull/5562