presto-main/src/main/java/io/prestosql/operator/scalar/DateTimeFunctions.java/DateTimeFunctions/addFieldValueTime
class DateTimeFunctions:    @Description("add the specified amount of time to the given time")
    @LiteralParameters("x")
    @ScalarFunction("date_add")
    @SqlType(StandardTypes.TIME)
    public static long addFieldValueTime(ConnectorSession session, @SqlType("varchar(x)") Slice unit, @SqlType(StandardTypes.BIGINT) long value, @SqlType(StandardTypes.TIME) long time)
    {
        if (session.isLegacyTimestamp()) {
            ISOChronology chronology = getChronology(session.getTimeZoneKey());
            return modulo24Hour(chronology, getTimeField(chronology, unit).add(time, toIntExact(value)));
        }

        return modulo24Hour(getTimeField(UTC_CHRONOLOGY, unit).add(time, toIntExact(value)));
    }