ARM VERSION 1.2 - Manual (Page 215)

Thumb Instruction Reference
ARM DUI 0068B Copyright © 2000, 2001 ARM Limited. All rights reserved. 5-21
5.2.5 ADC, SBC, and MUL
Add with carry, Subtract with carry, and Multiply.
Syntax
op Rd, Rm
where:
op is one of ADC , SBC , or MUL .
Rd is the destination register. It also contains the first operand.
Rm is a register containing the second operand.
Usage
ADC adds the values in Rd and Rm , together with the carry flag, and places the result in Rd .
Use this to synthesize multiword addition.
SBC subtracts the value in Rm from the value in Rd , taking account of the carry flag, and
places the result in Rd . Use this to synthesize multiword subtraction.
MUL multiplies the values in Rd and Rm , and places the result in Rd .
Restrictions
Rd , and Rm , must be low registers (that is, in the range r0 to r7).
Condition flags
ADC and SBC update the N, Z, C, and V flags.
MUL updates the N and Z flags.
In ARM architecture version 4 and earlier, MUL corrupts the C and V flags. In ARM
architecture version 5 and later, MUL has no effect on the C and V flags.
Architectures
These instructions are available in all T variants of the ARM architecture.
Example
ADC r2,r4