RFR: 8349523: Unused runtime calls to drem/frem should be removed [v2]

[Christian Hagedorn]

On Fri, 21 Feb 2025 15:41:34 GMT, Marc Chevalier <duke at openjdk.org> wrote:

>> Remove frem and drem macros nodes when the result is not used. These nodes have other outputs (like memory), which is not meaningful, but preventing them to be dropped so easily. This patch removes the useless frem/drem nodes, and by rewiring the inputs to the outputs.
>> 
>> Thanks,
>> Marc
>
> Marc Chevalier has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Fix and use replace_with_con

Would be nice to also have an IR test where `drem/frem` only becomes useless in a later compile phase (i.e. first used after parsing and then becomes unused at a later point).  Otherwise, looks good to me, too.

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Marked as reviewed by chagedorn (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/23694#pullrequestreview-2636112098