@ConstantFunction(name = "add", argTypes = {SMALLINT, SMALLINT}, returnType = SMALLINT, isMonotonic = true)
    public static ConstantOperator addSmallInt(ConstantOperator first, ConstantOperator second) {
        return ConstantOperator.createSmallInt((short) Math.addExact(first.getSmallint(), second.getSmallint()));
    }
@Test
    public void addSmallInt() {
        assertEquals(20,
                ScalarOperatorFunctions.addSmallInt(O_SI_10, O_SI_10).getSmallint());
    }