ARM Instruction Reference

Note

All values are treated as two’s complement signed integers by these instructions.

Condition flags

These instructions do not affect the N, Z, C, and V flags. If saturation occurs, they set the Q flag. To read the state of the Q flag, use an MRS instruction (see MRS on page 4-73).

Note

These instructions never clear the Q flag, even if saturation does not occur. To clear the Q flag, use an MSR instruction (see MSR on page 4-74).

Architectures

These instructions are available in E variants of ARM architecture v5 and above.

Examples

QADD

r0,r1,r9

QDSUBLT r9,r0,r1

Examples

QSUBS

r3,r4,r2

;

use

of

S suffix not allowed

QDADD

r11,r15,r0

;

use

of

r15 not allowed

4-56

Copyright © 2000, 2001 ARM Limited. All rights reserved.

ARM DUI 0068B

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ARM VERSION 1.2 manual Qadd