ST STM32WB Series Programming Manual

The STM32 Cortex-M4 instruction set PM0214
94/262 PM0214 Rev 9
3.5.10 SHADD16 and SHADD8
Signed Halving Add 16 and Signed Halving Add 8
Syntax
op{cond}{Rd,} Rn, Rm
Where:
• op is any of the following:
SHADD16: Signed halving add 16.
SHADD8: Signed halving add 8.
• ‘cond’ is an optional condition code (see Conditional execution on page 65).
• ‘Rd’ is the destination register.
• ‘Rn’ is the register holding the operand.
• ‘Rm’ is the second operand register.
Operation
Use these instructions to add 16-bit and 8-bit data and then to halve the result before writing
the result to the destination register:
The SHADD16 instruction:
1. Adds each halfword from the first operand to the corresponding halfword of the second
operand.
2. Shuffles the result by one bit to the right, halving the data.
3. Writes the halfword results in the destination register.
The SHADDB8 instruction:
1. Adds each byte of the first operand to the corresponding byte of the second operand.
2. Shuffles the result by one bit to the right, halving the data.
3. Writes the byte results in the destination register.
Restrictions
Do not use SP and do not use PC.
Condition flags
These instructions do not change the flags.
Examples
SHADD16 R1, R0 ; Adds halfwords in R0 to corresponding halfword of R1 &
; writes halved result to corresponding halfword in R1
SHADD8 R4, R0, R5 ; Adds bytes of R0 to corresponding byte in R5 and
; writes halved result to corresponding byte in R4.

ST STM32WB Series Specifications

General

Brand	ST
Model	STM32WB Series
Category	Computer Hardware
Language	English