Remove value_range_constant_singleton

[Richard Biener]

On Tue, Jun 11, 2019 at 12:27 PM Aldy Hernandez <aldyh@redhat.com> wrote:
>
> We already have value_range::singleton_p.  No need for a separate
> external function with the same functionality.
>
> OK?

OK.

Shame that there isn't some nicer syntax for

-  return value_range_constant_singleton (get_value_range (op));
+  tree t;
+  if (get_value_range (op)->singleton_p (&t))
+    return t;
+  return NULL;

Richard.