ARM Instruction Reference

4.3.3AND, ORR, EOR, and BIC

Logical AND, OR, Exclusive OR and Bit Clear.

Syntax

op{cond}{S} Rd, Rn, Operand2 where:

op

is one of AND, ORR, EOR, or BIC.

cond

is an optional condition code (see Conditional execution on page 4-4).

Sis an optional suffix. If S is specified, the condition code flags are updated on the result of the operation (see Conditional execution on page 4-4).

Rd

is the ARM register for the result.

Rn

is the ARM register holding the first operand.

Operand2

is a flexible second operand. See Flexible second operand on page 4-24

 

for details of the options.

Usage

The AND, EOR, and ORR instructions perform bitwise AND, Exclusive OR, and OR operations on the values in Rn and Operand2.

The BIC (BIt Clear) instruction performs an AND operation on the bits in Rn with the complements of the corresponding bits in the value of Operand2.

In certain circumstances, the assembler can substitute BIC for AND, or AND for BIC. Be aware of this when reading disassembly listings. See Instruction substitution on page 4-26 for details.

Condition flags

If S is specified, these instructions:

update the N and Z flags according to the result

can update the C flag during the calculation of Operand2 (see Flexible second operand on page 4-24)

do not affect the V flag.

4-30

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

ARM DUI 0068B

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ARM VERSION 1.2 3 AND, ORR, EOR, and BIC, Logical AND, OR, Exclusive or and Bit Clear, Is one of AND, ORR, EOR, or BIC