presto-main/src/main/java/io/prestosql/operator/HashBuilderOperator.java/HashBuilderOperator/needsInput
class HashBuilderOperator:    @Override
    public boolean needsInput()
    {
        boolean stateNeedsInput = (state == State.CONSUMING_INPUT)
                || (state == State.SPILLING_INPUT && spillInProgress.isDone());

        return stateNeedsInput && !lookupSourceFactoryDestroyed.isDone();
    }