[Bug tree-optimization/113187] New: `(X & C1) | C2` Simplifies to `A & (C1 | C2)` iff `(A & C2) == C2`

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113187

            Bug ID: 113187
           Summary: `(X & C1) | C2` Simplifies to `A & (C1 | C2)` iff `(A
                    & C2) == C2`
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---

Take:
```
int f(int X)
{
  int C1 = 0x1;
  int C2 = 0x2;
  if ((X & C2) != C2)
    __builtin_unreachable();
  return (X & C1) | C2;
}
```

This should be optimized to just `return X & 3;` as `X&0x2` is known to be
already 0x2.