Is there a reason you are not dividing by 4 (in other words why 255 and not 256, 1023 and not 1024?)
result = potValue / 4 ;
or with shifting right:
result = potValue >> 2 ;
Or if the slight difference matters, there is a built-in function specifically for this task:
result := map (potValue, 0, 1023, 0, 255) ;