[Bug middle-end/116454] [13 Regression] `*++ptr * 1j` is handled incorrectly with -ffast-math, increments ptr twice since r0-77972-g9f5396713d9e18

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116454

--- Comment #14 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-13 branch has been updated by Richard Biener
<rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:a5859de5504b8574de329a53d5ca04613ae4cf08

commit r13-10147-ga5859de5504b8574de329a53d5ca04613ae4cf08
Author: Andrew Pinski <quic_apinski@quicinc.com>
Date:   Wed Aug 21 17:41:38 2024 -0700

    fold: Fix `a * 1j` if a has side effects [PR116454]

    The problem here was a missing save_expr around arg0 since
    it is used twice, once in REALPART_EXPR and once in IMAGPART_EXPR.
    Thia adds the save_expr and reformats the code slightly so it is a
    little easier to understand.  It excludes the case when arg0 is
    a COMPLEX_EXPR since in that case we'll end up with the distinct
    real and imaginary parts.  This is important to retain early
    optimization in some testcases.

    Bootstapped and tested on x86_64-linux-gnu with no regressions.

            PR middle-end/116454

    gcc/ChangeLog:

            * fold-const.cc (fold_binary_loc): Fix `a * +-1i`
            by wrapping arg0 with save_expr when it is not COMPLEX_EXPR.

    gcc/testsuite/ChangeLog:

            * gcc.dg/torture/pr116454-1.c: New test.
            * gcc.dg/torture/pr116454-2.c: New test.

    Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>
    Co-Authored-By: Richard Biener  <rguenther@suse.de>
    (cherry picked from commit b07f8a301158e53717b8688cc8ea430b6f02574c)