Analog Devices ADSP-BF53x Blackfin Reference page 519

Functional Description
The Add instruction adds two source values and places the result in a des-
tination register.
There are two ways to specify addition on 32-bit data in D-registers:
• One does not support saturation (16-bit instruction length)
• The other supports optional saturation (32-bit instruction length)
The shorter 16-bit instruction takes up less memory space. The larger
32-bit instruction can sometimes save execution time because it can be
issued in parallel with certain other instructions. See
page 15-5.
The D-register version that accepts 16-bit half-word operands stores the
result in a half-word data register. This version accepts any combination
of upper and lower half-register operands, and places the results in the
upper or lower half of the destination register at the user's discretion.
All versions that manipulate 16-bit data are 32 bits long.
Options
In the syntax, where
values.
– saturate the result
(S)
– no saturation
(NS)
See "Saturation" on page 1-17
ADSP-BF53x/BF56x Blackfin Processor Programming Reference
appears, substitute one of the following
sat_flag
for a description of saturation behavior.
Arithmetic Operations
"Parallel Issue" on
15-7