Note that, if the value-range check will be extended for the slice with compile-time known boundaries in the future, `UL` suffx should be printed properly.

```d
// -m64 is necessary
void main() {
    int[] data;
    foreach (ubyte i, x; data[0 .. cast(size_t)(long.max + 1)]) {}
}
```

But this PR does not support above case, so it is not an issue now.