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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/110931] [14 Regression] Dead Code Elimination
 Regression since r14-2890-gcc2003cd875
Date: Mon, 07 Aug 2023 15:25:19 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110931

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Basically there is a missing VRP happening here:
l.0_1   [irange] int [-INF, -65536][0, 0][65536, +INF]
Partial equiv (b_6 pe8 l.0_1)
    <bb 3> :
    b_6 =3D (char) l.0_1;
...
Obvious that b_6 will have the range [0,0] as the other parts of l.0_1 is
outside of that range. But for some reason VRP didn't figure that out here =
...

I don't understand how this is supposed to work=