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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/110503] [13/14 Regression] Dead Code
 Elimination Regression at -O3 since  r13-322-g7f04b0d786e
Date: Fri, 30 Jun 2023 21:47:47 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110503

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2023-06-30
             Status|UNCONFIRMED                 |NEW

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #1)
> I noticed there is a missing optimization here (during VRP1):
>   _29 =3D _11 =3D=3D 0;
>   _30 =3D (unsigned int) _29;
>   _14 =3D -_30;
>   if (_14 > 2)
>=20
> That is just:
>   if (_14 !=3D 0)
> or:
>   if (_29 !=3D 0)
> or rather:
>   if (_11 =3D=3D 0)

I wonder if the above will decrease the "size" estimates enough to optimize
this again ...

Oh and had:
  # RANGE [irange] int [-128, 127]
  _10 =3D (intD.6) _9;
  # RANGE [irange] int [0, 1] NONZERO 0x1
  _11 =3D 1 % _10;

I wonder if we could optimize `1 % b` into just `b !=3D 1` (since 1 % 0 is
undefined) which will further reduce things here.=