[Bug middle-end/116891] [12 Regression] invalid optimization of -fma(-x,x,-z) when -O3 and -frounding-math are used

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116891

--- Comment #18 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-12 branch has been updated by Richard Biener
<rgue...@gcc.gnu.org>:

https://gcc.gnu.org/g:c0c5db68331ea8814db45ecd90ba842818e623fa

commit r12-10908-gc0c5db68331ea8814db45ecd90ba842818e623fa
Author: Richard Biener <rguent...@suse.de>
Date:   Mon Oct 14 08:11:22 2024 +0200

    middle-end/116891 - fix (negate (IFN_FNMS@3 @0 @1 @2)) -> (IFN_FMA @0 @1
@2)

    Transforming -fma (-a, b, -c) to fma (a, b, c) is only valid when
    not rounding towards -inf or +inf as the sign of the multiplication
    changes.

            PR middle-end/116891
            * match.pd ((negate (IFN_FNMS@3 @0 @1 @2)) -> (IFN_FMA @0 @1 @2)):
            Only enable for !HONOR_SIGN_DEPENDENT_ROUNDING.

    (cherry picked from commit c53bd48c6920bc1f4039b6682aafbf414a600e47)