[Bug tree-optimization/103417] [12 Regression] wrong code at -O1 and above on x86_64-linux-gnu since r12-5489

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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103417

--- Comment #6 from CVS 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:94912212d3d1be0b1c490e9b5f45165ef5f30d8a

commit r12-5513-g94912212d3d1be0b1c490e9b5f45165ef5f30d8a
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Thu Nov 25 10:47:24 2021 +0100

    match.pd: Fix up the recent bitmask_inv_cst_vector_p simplification
[PR103417]

    The following testcase is miscompiled since the r12-5489-g0888d6bbe97e10
    changes.
    The simplification triggers on
    (x & 4294967040U) >= 0U
    and turns it into:
    x <= 255U
    which is incorrect, it should fold to 1 because unsigned >= 0U is always
    true and normally the
    /* Non-equality compare simplifications from fold_binary  */
         (if (wi::to_wide (cst) == min)
           (if (cmp == GE_EXPR)
            { constant_boolean_node (true, type); })
    simplification folds that, but this simplification was done earlier.

    The simplification correctly doesn't include lt which has the same
    reason why it shouldn't be handled, we'll fold it to 0 elsewhere.

    But, IMNSHO while it isn't incorrect to handle le and gt there, it is
    unnecessary.  Because (x & cst) <= 0U and (x & cst) > 0U should
    never appear, again in
    /* Non-equality compare simplifications from fold_binary  */
    we have a simplification for it:
           (if (cmp == LE_EXPR)
            (eq @2 @1))
           (if (cmp == GT_EXPR)
            (ne @2 @1))))
    This is done for
      (cmp (convert?@2 @0) uniform_integer_cst_p@1)
    and so should be done for both integers and vectors.
    As the bitmask_inv_cst_vector_p simplification only handles
    eq and ne for signed types, I think it can be simplified to just
    following patch.

    2021-11-25  Jakub Jelinek  <jakub@redhat.com>

            PR tree-optimization/103417
            * match.pd ((X & Y) CMP 0): Only handle eq and ne.  Commonalize
            common tests.

            * gcc.c-torture/execute/pr103417.c: New test.