presto-main/src/main/java/io/prestosql/sql/planner/optimizations/IndexJoinOptimizer.java/IndexSourceRewriter/visitFilter
class IndexSourceRewriter:        @Override
        public PlanNode visitFilter(FilterNode node, RewriteContext<Context> context)
        {
            if (node.getSource() instanceof TableScanNode) {
                return planTableScan((TableScanNode) node.getSource(), node.getPredicate(), context.get());
            }

            return context.defaultRewrite(node, new Context(context.get().getLookupSymbols(), context.get().getSuccess()));
        }