I need control function for super user

I'm making control like this checking subs if they subed I'm showing them content.

<?php $sub_id = 1 ; if(current_user_on_subscription($sub_id)){  ?>

show premium content

<?php } else{  ?>

you are not sub

<?php } ?>

But I need one more contro lfor super user.

For ex:

if(current_user_on_subscription($sub_id or super_user()))

I want to show content subs and super users. Is there a function for this ?