[Bug tree-optimization/125652] [14/15/16/17 Regression] wrong code at -O3 on x86_64-linux-gnu

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125652

--- Comment #5 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Biener <rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:de3a13dd7f6c2856e96fc2b7924f9b34b638940f

commit r17-1421-gde3a13dd7f6c2856e96fc2b7924f9b34b638940f
Author: Richard Biener <rguenther@suse.de>
Date:   Mon Jun 8 10:50:35 2026 +0200

    tree-optimization/125652 - wrong code with SCEV

    The following fixes a latent issue in chrec_fold_plus_poly_poly
    which suffers from being prone to signed overflow UB in the way
    it associates additions when accumulating two polynomical CHRECs.
    Similar to r16-2781-gafafae097232e7 the following catches the
    obvious cases when constants are involved without trying to address
    the actual underlying issue.

            PR tree-optimization/125652
            * tree-chrec.cc (chrec_fold_plus_poly_poly): Avoid UB
            integer overflow in accumulating CHREC_RIGHT.

            * gcc.dg/torture/pr125652.c: New testcase.