Since the low-order two bytes are placed in the front and the high-order two bytes are placed in the back when stored in the register, the calculation needs to adjust the order of the two bytes before and after.
Since the low two bytes are placed in the register and the two bytes in the high position are placed at the back, the calculation needs to adjust the order of the first and second bytes.
Since the low two bytes are placed in the front and the high two bytes are placed at the back, the calculation needs to adjust the order of the two bytes<br>