4.5.1. Saturating arithmetic

These operations are saturating (SAT). This means that, for some value of 2n that depends on the instruction:

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 MSR instruction (see MSR).

The Q flag can also be set by two other instructions (see SMULxy and SMLAxy and SMULWy and SMLAWy), but these instructions do not saturate.

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