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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/102872] If statement is always false but not
 figured out at gimple level
Date: Sat, 20 Nov 2021 08:59:18 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D102872

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I wonder if we should just do this:
(for neeq (ne eq)
(simplify
 (neeq (convert:s @0) integer_zerop@1)
   (with
    {
      tree inside_type =3D TREE_TYPE (@0);
      tree outer_type =3D TREE_TYPE (@1);
    }
    (if (TYPE_PRECISION (inside_type) > TYPE_PRECISION (outer_type))
     (neeq (bit_and @0
            { wide_int_to_tree (type0,
                                wi::mask (TYPE_PRECISION (inside_type),
                                          false,
                                          TYPE_PRECISION (outer_type))); })
             { build_zero_cst (inside_type); })))))
)

Or does the bit_and to a convert make better sense? I don't care either way
really but it would be a good idea to chose one or the other really.=