yes of course miss you can get IISc for TA or RA dept as per your rank,all the best for gate cs 2018 you will get IISc ,other premier NITs topmost Warangal,Suratkhal,IIIT Hyderabad are alsl good for placements,but aim for only IISc,
It doesn't matter from where you come from, all that matters is where you are going.