RFR: 8316186: RISC-V: Remove PlatformCmpxchg<4>

[Fei Yang]

On Tue, 19 Sep 2023 07:56:39 GMT, Fei Yang <fyang at openjdk.org> wrote:

> > Can you add 'assert' code above and check hs_err which case this is?
> 
> Yeah, I have added code change from this pull request and your 'assert' code and doing a native release build with GCC 11.

Turns out that the issue won't reproduce if adding your 'assert' code.
That is to say, it only triggers with openjdk release build built with this PR and GCC version 10 or 11 on my side.

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PR Comment: https://git.openjdk.org/jdk/pull/15715#issuecomment-1725882229