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 114

SAM4S [DATASHEET]

11100E–ATARM–24-Jul-13

Signed Add 16 and Signed Add 8

Syntax

op{cond}{Rd,} Rn, Rm

where:

op

is any of:

SADD16 Performs two 16-bit signed integer additions.

SADD8 Performs four 8-bit signed integer additions.

cond

Rd

is the destination register.

Rn

is the first register holding the operand.

Rm

is the second register holding the operand.

Operation

Use these instructions to perform a halfword or byte add in parallel:

The SADD16 instruction: 

1.

Adds each halfword from the first operand to the corresponding halfword of the second operand.

2.

Writes the result in the corresponding halfwords of the destination register.

The SADD8 instruction: 

1.

Adds each byte of the first operand to the corresponding byte of the second operand.

Writes the result in the corresponding bytes of the destination register.

Restrictions

Do not use SP and do not use PC

Condition Flags

These instructions do not change the flags.

Examples

SADD16 R1, R0     ; Adds the halfwords in R0 to the corresponding 

                  ; halfwords of R1 and writes to corresponding halfword 

                  ; of R1.

SADD8  R4, R0, R5 ; Adds bytes of R0 to the corresponding byte in R5 and

                  ; writes to the corresponding byte in R4.