regent: Fix for index launch optimization.
regent: Fix for index launch optimization.

StanfordLegion/legion,chuckatkins/legion,StanfordLegion/legion,chuckatkins/legion,sdalton1/legion,sdalton1/legion,sdalton1/legion,chuckatkins/legion,StanfordLegion/legion,sdalton1/legion,StanfordLegion/legion,chuckatkins/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,sdalton1/legion,sdalton1/legion,chuckatkins/legion,chuckatkins/legion,chuckatkins/legion