[Bug tree-optimization/112096] `(a || b) ? a : b` should be simplified to a

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112096

--- Comment #5 from Drea Pinski <pinskia at gcc dot gnu.org> ---
This was fixed via VN improvements for GCC 15 at -O2.

For -O1, t0 we have:
```
  <bb 2> [local count: 1073741824]:
  _1 = x_3(D) | y_4(D);
  if (_1 == 0)
    goto <bb 3>; [34.00%]
  else
    goto <bb 4>; [66.00%]

  <bb 3> [local count: 365072224]:

  <bb 4> [local count: 1073741824]:
  # _2 = PHI <x_3(D)(3), y_4(D)(2)>
```

So:
```
(simplify
 (cond (eq (bit_ior:c @0 @1) integer_zerop) @0 @1)
 @1)

(simplify
 (cond (eq (bit_ior:c @0 @1) integer_zerop) integer_zerop @1)
 @1)
```
for t0/t0_/t1/t1_.