legion: more work on detecting empty index spaces and not adding in unnecessary profiling requests
legion: more work on detecting empty index spaces and not adding in unnecessary profiling requests

StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion