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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/114894] `a == 0 ? 0 : a * b` -> `a * b`
 likewise for `a & b`
Date: Tue, 30 Apr 2024 18:18:51 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114894

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
And divides should happen if we know if the divisor is non-zero:
eg:
```
int fdiv(int a, int b)
{
        if (b =3D=3D 0) __builtin_unreachable();
        int c =3D a / b;
        int d =3D a !=3D 0;
        return c & -d;
}

```

Phi-OPT value-replacement does handle it for ifs right now:
```
int fmul3(int a, int b)
{
        if (b =3D=3D 0) __builtin_unreachable();
        int c =3D a / b;
        if (a =3D=3D 0)  return 0;
        return c;
        int d =3D a !=3D 0;
        return c & -d;
}
```=