RFR: 8307104: [AIX] VM crashes with UseRTMLocking on Power10

[Lutz Schmidt]

On Fri, 28 Apr 2023 13:13:41 GMT, Martin Doerr <mdoerr at openjdk.org> wrote:

> We need to prevent usage of transactional memory (UseRTMLocking) on Power10 which doesn't support it. The VM crashes with SIGILL on AIX when trying to use it.
> 
> I'm also changing the AIX specific check for the case in which somebody uses Power10 with -XX:PowerArchitecturePPC64=8 (or 9).
> The Linux specific code is fine as it is.
> 
> This change is small and should get considered for backports. We may remove the RTM code completely for future JDKs.

Looks good to me. 
Goodbye to an interesting feature which never get traction and was complicated to exploit.

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Marked as reviewed by lucy (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/13717#pullrequestreview-1408049202