presto-main/src/main/java/io/prestosql/operator/aggregation/BitwiseOrAggregation.java/BitwiseOrAggregation/combine
class BitwiseOrAggregation:    @CombineFunction
    public static void combine(@AggregationState NullableLongState state, @AggregationState NullableLongState otherState)
    {
        if (state.isNull()) {
            state.setNull(otherState.isNull());
            state.setLong(otherState.getLong());
        }
        else if (!otherState.isNull()) {
            state.setLong(state.getLong() | otherState.getLong());
        }
    }