https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122103

--- Comment #12 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Tamar Christina <[email protected]>:

https://gcc.gnu.org/g:772b847d99d5e3d6caf40cead5ecf15575125059

commit r16-6508-g772b847d99d5e3d6caf40cead5ecf15575125059
Author: Tamar Christina <[email protected]>
Date:   Mon Jan 5 20:54:35 2026 +0000

    middle-end: extend fma -> fms transformation to conditional optab
[PR122103]

    Currently in the simplications between if-conversion and vect we rely on
    match.pd to rewrite FMA into FMS if the accumulator is on a negated value.

    However if if-conversion instead produces a COND_FMA then this doesn't work
and
    so the vectorizer can't generate a vector FMS or it's other variant.

    This extends the rules to include the COND_FMA variants.  Because this
happens
    before the vectorization the vectorizer will take care of generating the
LEN
    variants and as such we don't need match.pd to know about those.

    The added rules are the same as the ones directly above them just changing
    FMA to COND_FMA.

    gcc/ChangeLog:

            PR tree-optimization/122103
            * match.pd: Add COND_FMA to COND_FMS rewrite rules.

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