RFR: 8357554: Enable vectorization of Bool -> CMove with different type size (on riscv) [v5]

[Hamlin Li]

On Wed, 10 Dec 2025 21:03:30 GMT, Hamlin Li <mli at openjdk.org> wrote:

>> Hi,
>> 
>> Can you help to review this patch?
>> 
>> This patch enables the vectorization of statement like `op_1 bop op_2 ? res_f_d_1 : res_f_d_2` in a loop, where op_x's size is different from res_f_d_x's.
>> 
>> To assist with code review, this pr contains only the shared code change, is splitted from https://github.com/openjdk/jdk/pull/28230, which enable & implement the riscv part. The similar optimization could be extended to other platforms. 
>> 
>> ## Some background
>> 
>> Previously, it's https://github.com/openjdk/jdk/pull/25336, which was blocked by unsigned comparison issue. The issue was recently resolved by https://github.com/openjdk/jdk/pull/27942, so I'm re-start working on this optimization.
>> 
>> This pr only relaxes one of the constraints in https://github.com/openjdk/jdk/pull/25336, i.e. transform CMoveF/D to vector operations no matter what's the size of comparison's operator, but remove the optimization of transform CMoveI/L to vector operations which I think need more investigation.
>> 
>> # Test
>> ## Jtreg
>> 
>> in progress...
>> 
>> ## Performance
>> 
>> check the performance data in https://github.com/openjdk/jdk/pull/25341 on riscv.
>> 
>> Thanks
>
> Hamlin Li has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains 38 additional commits since the last revision:
> 
>  - enable riscv
>  - tests
>  - review comment
>  - Merge branch 'master' into vectorize-CMove-Bool
>  - Merge branch 'openjdk:master' into master
>  - Merge branch 'openjdk:master' into master
>  - Merge branch 'master' into vectorize-CMove-Bool
>  - Merge branch 'openjdk:master' into master
>  - Merge branch 'openjdk:master' into master
>  - fix typo
>  - ... and 28 more: https://git.openjdk.org/jdk/compare/10082235...ecc84adc

This pr will cause some test failure, I'll investigate futher and update later.

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PR Comment: https://git.openjdk.org/jdk/pull/28231#issuecomment-3669534319