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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/108370] gcc doesn't merge bitwise-AND if an explicit
 comparison against 0 is given
Date: Sat, 16 Sep 2023 23:48:45 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D108370

--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #5)
>   _10 =3D _9 >> 1;
>   _11 =3D (bool) _10;
>   if (_11 !=3D 0)
>=20
>=20
> Should just be optimized to:
> _t =3D _9 & 1
> if (_t !=3D 0)
>=20
> Let me add that to match.

We do handle:
/* Fold ((X << C1) & C2) cmp C3 into (X & (C2 >> C1)) cmp (C3 >> C1)
        ((X >> C1) & C2) cmp C3 into (X & (C2 << C1)) cmp (C3 << C1).  */=