Gary Illyes , Google's Webmaster Trends Analyst in a tweet earlier shared their current state of affairs  for managing their desktop and mobile search engine index.
 

@marie_mickael no, that wouldn't make much sense at the moment since we only have a "desktop index" @JohnMu

— Gary Illyes (@methode) September 17, 2015

Mobile now constitues more than half of the internet traffic, it would make sense to have a separate mobile and desktop index. Currently having a responsive website does help with your search engine ranking and we expect that to stay unchanged.