[Bug tree-optimization/113756] [14 regression] Wrong code at -O2 on x86_64-linux-gnu since r14-2780-g39f117d6c87

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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113756

--- Comment #4 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jakub Jelinek <jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:29998cc8a21b3a52f706275923166cd1f95d0555

commit r14-8837-g29998cc8a21b3a52f706275923166cd1f95d0555
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Wed Feb 7 10:59:06 2024 +0100

    range-op: Fix up ABSU_EXPR handling [PR113756]

    ABSU_EXPR unary expr is special because it has a signed integer
    argument and unsigned integer result (of the same precision).

    The following testcase is miscompiled since ABSU_EXPR handling has
    been added to range-op because it uses widest_int::from with the
    result sign (i.e. UNSIGNED) rather than the operand sign (i.e. SIGNED),
    so e.g. for the 32-bit int argument mask ends up 0xffffffc1 or something
    similar and even when it has most significant bit in the precision set,
    in widest_int (tree-ssa-ccp.cc really should stop using widest_int, but
    that is I think stage1 task) it doesn't appear to be negative and so
    bit_value_unop ABSU_EXPR doesn't set the resulting mask/value from
    oring of the argument and its negation.

    Fixed thusly, not doing that for GIMPLE_BINARY_RHS because I don't know
    about a binary op that would need something similar.

    2024-02-06  Jakub Jelinek  <jakub@redhat.com>

            PR tree-optimization/113756
            * range-op.cc (update_known_bitmask): For GIMPLE_UNARY_RHS,
            use TYPE_SIGN (lh.type ()) instead of sign for widest_int::from
            of lh_bits value and mask.

            * gcc.dg/pr113756.c: New test.