RFR: 8352248: Check if CMoveX is supported [v2]

[Ludovic Henry]

On Wed, 19 Mar 2025 09:43:24 GMT, Hamlin Li <mli at openjdk.org> wrote:

>> Hi,
>> Can you help to review this patch?
>> 
>> Currenlty, seems CMoveX are fully supported on most platforms, except of riscv64.
>> On riscv64, there is no efficient way to implement CMoveF/D as other CMoveX (e.g. CMoveI), but it will still bring benefit by just supporting CMoveX without CMoveF/D. This patch is to supply such option.
>> 
>> As other platforms already supported CMoveX, this patch should not impact them, as `!CMoveNode::supported(_igvn.type(phi))` should always be false.
>> 
>> BTW, in a subsequent pr for riscv, I'll implement CMoveX except of CMoveF/D, and also return false for CMoveF/D in Matcher::match_rule_supported.
>> 
>> Thanks!
>
> Hamlin Li has updated the pull request incrementally with one additional commit since the last revision:
> 
>   minor

Marked as reviewed by luhenry (Committer).

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PR Review: https://git.openjdk.org/jdk/pull/24095#pullrequestreview-2705571912