presto-main/src/main/java/io/prestosql/sql/planner/optimizations/AddLocalExchanges.java/AddLocalExchanges/optimize
class AddLocalExchanges:    @Override
    public PlanNode optimize(PlanNode plan, Session session, TypeProvider types, SymbolAllocator symbolAllocator, PlanNodeIdAllocator idAllocator, WarningCollector warningCollector)
    {
        PlanWithProperties result = plan.accept(new Rewriter(symbolAllocator, idAllocator, session), any());
        return result.getNode();
    }