The saturating instructions are:
Some of the parallel instructions are also saturating.
These operations are saturating (
This means that, for some value of 2
depends on the instruction:
for a signed saturating operation, if the full result would be less than -2
n, the result returned is -2
for an unsigned saturating operation, if the full result would be negative, the result returned is zero
if the full result would be greater than 2
n- 1, the result returned is 2
When any of these things occurs, it is called saturation. Some instructions set the Q flag when saturation occurs.
Saturating instructions do not clear the Q flag when saturation
does not occur. To clear the Q flag, use an
The Q flag can also be set by two other instructions, but these instructions do not saturate.