https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110539
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Here is a testcase for the missing optimization (at -O1) which is optimized at
the RTL level (for some targets but not all):
```
int f(int a)
{
int b = a & 1;
int c = b != 0;
return c == b;
}
```
Though it does optimize at -O2 because VRP changes: `b != 0` into `(_Bool)
b_4`.
