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/*
* linux/arch/arm/lib/testchangebit.S
*
* Copyright (C) 1995-1996 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
.text
ENTRY(test_and_change_bit)
add r1, r1, r0, lsr #3
and r3, r0, #7
mov r0, #1
save_and_disable_irqs ip, r2
ldrb r2, [r1]
tst r2, r0, lsl r3
eor r2, r2, r0, lsl r3
strb r2, [r1]
restore_irqs ip
moveq r0, #0
RETINSTR(mov,pc,lr)
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