[Bug tree-optimization/125923] [17 regression] ICE on valid code at -O3 with "-fno-tree-dce" on x86_64-linux-gnu: in factor_out_conditional_load, at tree-ssa-phiopt.cc:3716 after r17-1704

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125923

--- Comment #4 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The trunk branch has been updated by Andrew Pinski <pinskia@gcc.gnu.org>:

https://gcc.gnu.org/g:88b9e82a4429373468b65ccbe7fde86bec3f697b

commit r17-1755-g88b9e82a4429373468b65ccbe7fde86bec3f697b
Author: Andrew Pinski <andrew.pinski@oss.qualcomm.com>
Date:   Sun Jun 21 16:10:15 2026 -0700

    phiopt: Reject instead of assert that the 2 vuse of the loads are the same
[PR125923]

    So it turns out I thought we would always get a virtual phi when there was
a store
    in front of the load. This is correct for all normal code except if heading
into
    an infinite loop where there are no stores/loads. Since this is leading to
    an infinite loop, rejecting this case does not change performance at all.

    Bootstrapped and tested on x86_64-linux-gnu.

            PR tree-optimization/125923

    gcc/ChangeLog:

            * tree-ssa-phiopt.cc (factor_out_conditional_load): Change
            assert of the vuse being the same to rejecting if they are
            different without a virtual phi.

    gcc/testsuite/ChangeLog:

            * gcc.dg/torture/pr125923-1.c: New test.

    Signed-off-by: Andrew Pinski <andrew.pinski@oss.qualcomm.com>