https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123121

--- Comment #7 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Vladimir Makarov <[email protected]>:

https://gcc.gnu.org/g:c10076b34d3ede485bfb306b2a91feeee8368cd5

commit r16-6654-gc10076b34d3ede485bfb306b2a91feeee8368cd5
Author: Vladimir N. Makarov <[email protected]>
Date:   Fri Jan 9 10:36:29 2026 -0500

    [PR123121, LRA]: Fix wrong rematerialization of insns with several outputs

    LRA in the test case, rematerialize insn with div/mod where div result
    is not used.  Still div result requires ax which is used by different
    pseudos at point of rematerialization and this clobbers the pseudo
    value.  The patch solves the problem by constraining to single set
    insns as we always rematerialize only one pseudo value.  Also there is
    no sense to rematerialize div/mod as usually their latency is more
    than load value from CPU cache.  The patch explicitly excludes such
    insns from rematerialization.

    gcc/ChangeLog:

            PR rtl-optimization/123121
            * lra-remat.cc (bad_for_rematerialization_p): Consider div/mod ops.
            (operand_to_remat): Exclude rematerialization of insns with
            multiple sets.

    gcc/testsuite/ChangeLog:

            PR rtl-optimization/123121
            * gcc.target/i386/pr123121.c: New.

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