RFR: 8357551: RISC-V: support CMoveF/D vectorization [v2]

[Emanuel Peter]

On Fri, 14 Nov 2025 18:11:28 GMT, Hamlin Li <mli at openjdk.org> wrote:

>> test/hotspot/jtreg/compiler/c2/irTests/TestScalarConditionalMove.java line 36:
>> 
>>> 34:  * @test
>>> 35:  * @summary Test conditional move.
>>> 36:  * @requires vm.simpleArch == "riscv64"
>> 
>> I would prefer if you could enable the test on all platforms, but just require the specific platform on the IR rules.
>> What would be even more fantastic: if you were able to also enable the IR rules for `x64` and `aarch64`, but we can also file a follow-up RFE for that.
>
> Make sense. I filed https://bugs.openjdk.org/browse/JDK-8371920 to track the task, will do it later after this pr.

I would suggest that you already make the move from `@requires` to IR rule level restrictions. But we can look at adding `x64` and `aarch64` in the separate RFE.

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

PR Review Comment: https://git.openjdk.org/jdk/pull/28309#discussion_r2532986110