Filter
Top Products
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