packusdw (saturated clamp from unsigned long to unsigned short),
packssduw (saturated clamp from signed long to unsigned short):
There is a condition for unsigned long inputs, range is “only” [0x00000000, 0x7FFFFFFF].
There is a condition for signed long inputs, range is “only” [0x80008000, 0x7FFFFFFF]. You can go to full signed long if there would exist “psubsd”, which does [...]