Atmel ARM-Based Evaluation Kit for SAM4S16C, 32-Bit ARM® Cortex® Microcontroller ATSAM4S-WPIR-RD ATSAM4S-WPIR-RD Data Sheet
Product codes
ATSAM4S-WPIR-RD
SAM4S Series [DATASHEET]
Atmel-11100G-ATARM-SAM4S-Datasheet_27-May-14
148
Syntax
op{X}{cond} Rd, Rn, Rm, Ra
;
where:
opis one of:
SMLAD Signed Multiply Accumulate Dual.
SMLADX Signed Multiply Accumulate Dual Reverse.
X specifies which halfword of the source register Rn is used as the multiply
opis one of:
SMLAD Signed Multiply Accumulate Dual.
SMLADX Signed Multiply Accumulate Dual Reverse.
X specifies which halfword of the source register Rn is used as the multiply
operand.
If X is omitted, the multiplications are bottom × bottom and top × top.
If X is present, the multiplications are bottom × top and top × bottom.
condis an optional condition code, see
condis an optional condition code, see
.
Rdis the destination register.
Rnis the first operand register holding the values to be multiplied.
Rmthe second operand register.
Rais the accumulate value.
Operation
The SMLAD and SMLADX instructions regard the two operands as four halfword 16-bit values. The SMLAD and
Rnis the first operand register holding the values to be multiplied.
Rmthe second operand register.
Rais the accumulate value.
Operation
The SMLAD and SMLADX instructions regard the two operands as four halfword 16-bit values. The SMLAD and
SMLADX instructions:
If X is not present, multiply the top signed halfword value in Rn with the top signed halfword of Rm and the
bottom signed halfword values in Rn with the bottom signed halfword of Rm.
Or if X is present, multiply the top signed halfword value in Rn with the bottom signed halfword of Rm and
the bottom signed halfword values in Rn with the top signed halfword of Rm.
Add both multiplication results to the signed 32-bit value in Ra.
Writes the 32-bit signed result of the multiplication and addition to Rd.
Restrictions
Do not use SP and do not use PC
Do not use SP and do not use PC
.
Condition Flags
These instructions do not change the flags.
Examples
These instructions do not change the flags.
Examples
SMLAD
R10, R2, R1, R5 ; Multiplies two halfword values in R2 with
; corresponding halfwords in R1, adds R5 and
; writes to R10
SMLALDX R0, R2, R4, R6
; Multiplies top halfword of R2 with bottom
; halfword of R4, multiplies bottom halfword of R2
; with top halfword of R4, adds R6 and writes to
; R0.
12.6.6.5 SMLAL and SMLALD
Signed Multiply Accumulate Long, Signed Multiply Accumulate Long (halfwords) and Signed Multiply Accumulate
Long Dual.
Syntax
Syntax
op{cond} RdLo, RdHi, Rn, Rm
op{XY}{cond} RdLo, RdHi, Rn, Rm