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From: "xxs_chy at outlook dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/114704] Missed optimization : eliminate store
 if the value is known in all predecessors
Date: Sat, 13 Apr 2024 13:39:27 +0000
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X-Bugzilla-Component: tree-optimization
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114704

--- Comment #3 from XChy <xxs_chy at outlook dot com> ---
(In reply to Andrew Pinski from comment #1)
> Confirmed. A more general testcase:
> ```
> void dummy();
>=20
> void src(int *p, int a){
>     int t =3D *p;
>     if(t =3D=3D a)
>         goto then;
>     else {
>         dummy();
>         t =3D *p;
>         if(t =3D=3D a)
>             goto then;
>         else
>             return;
>     }
>=20
> then:
>     *p =3D t; // *p is already a, it's dead now
> }
>=20
> ```

Do you mean "*p =3D a" at the end?=