presto-main/src/main/java/io/prestosql/sql/planner/LocalExecutionPlanner.java/IndexSourceContext/IndexSourceContext
class IndexSourceContext:        public IndexSourceContext(SetMultimap<Symbol, Integer> indexLookupToProbeInput)
        {
            this.indexLookupToProbeInput = ImmutableSetMultimap.copyOf(requireNonNull(indexLookupToProbeInput, "indexLookupToProbeInput is null"));
        }