[Bug tree-optimization/111168] New: a[0,1]|b[0,-1] == 0 is not reduced to a ==0 & b ==0 if a and b are defined by comparisons

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111168

            Bug ID: 111168
           Summary: a[0,1]|b[0,-1] == 0 is not reduced to a ==0 & b ==0 if
                    a and b are defined by comparisons
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Keywords: 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: ---

Take:
```
static inline int comLG_(int a, int b)
{
        int c = (a < b) * -1;
        return (a > b) | c;
}


int f(int a, int b)
{
        return comLG_(a,b) == 0;
}
```

This should be reduced down to just `(a < b) == 0 & (a > b) == 0` or rather
just `a == b`.