[Bug tree-optimization/126134] New: `((x&5)!=5 ? x|5 : x` -> `x|5` and `((a&5)==5?x|5:x` -> `x` are not done

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126134

            Bug ID: 126134
           Summary: `((x&5)!=5 ? x|5 : x` -> `x|5` and `((a&5)==5?x|5:x`
                    -> `x` are not done
           Product: gcc
           Version: 17.0
            Status: UNCONFIRMED
          Keywords: easyhack, missed-optimization
          Severity: enhancement
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---

```
int f(int a)
{
    if ((a&5)!=5)  return a | 5;
    return a;
}

int f1(int a)
{
    if ((a&5)==5)  return a | 5;
    return a;
}
```

f should simplify down to `return x|5`.
While f1 should simplify down to `return x`.

Note f1 is handled on the RTL level.
Note f1 could also be handled in VRP (will file a different bug for that).