xref: /minix3/common/lib/libc/arch/arm/atomic/atomic_xor_64.S (revision 0a6a1f1d05b60e214de2f05a7310ddd1f0e590e7)
1*0a6a1f1dSLionel Sambuc/*	$NetBSD: atomic_xor_64.S,v 1.3 2014/03/04 16:15:28 matt Exp $	*/
284d9c625SLionel Sambuc/*-
384d9c625SLionel Sambuc * Copyright (c) 2013 The NetBSD Foundation, Inc.
484d9c625SLionel Sambuc * All rights reserved.
584d9c625SLionel Sambuc *
684d9c625SLionel Sambuc * This code is derived from software contributed to The NetBSD Foundation
784d9c625SLionel Sambuc * by Matt Thomas <matt@3am-software.com>
884d9c625SLionel Sambuc *
984d9c625SLionel Sambuc * Redistribution and use in source and binary forms, with or without
1084d9c625SLionel Sambuc * modification, are permitted provided that the following conditions
1184d9c625SLionel Sambuc * are met:
1284d9c625SLionel Sambuc * 1. Redistributions of source code must retain the above copyright
1384d9c625SLionel Sambuc *    notice, this list of conditions and the following disclaimer.
1484d9c625SLionel Sambuc * 2. Redistributions in binary form must reproduce the above copyright
1584d9c625SLionel Sambuc *    notice, this list of conditions and the following disclaimer in the
1684d9c625SLionel Sambuc *    documentation and/or other materials provided with the distribution.
1784d9c625SLionel Sambuc *
1884d9c625SLionel Sambuc * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
1984d9c625SLionel Sambuc * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
2084d9c625SLionel Sambuc * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
2184d9c625SLionel Sambuc * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
2284d9c625SLionel Sambuc * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
2384d9c625SLionel Sambuc * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
2484d9c625SLionel Sambuc * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
2584d9c625SLionel Sambuc * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
2684d9c625SLionel Sambuc * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
2784d9c625SLionel Sambuc * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
2884d9c625SLionel Sambuc * POSSIBILITY OF SUCH DAMAGE.
2984d9c625SLionel Sambuc */
3084d9c625SLionel Sambuc
3184d9c625SLionel Sambuc#include "atomic_op_asm.h"
3284d9c625SLionel Sambuc
3384d9c625SLionel Sambuc#ifdef _ARM_ARCH_6
3484d9c625SLionel Sambuc
3584d9c625SLionel SambucENTRY_NP(_atomic_xor_64_nv)
3684d9c625SLionel Sambuc	push	{r3,r4}			/* save temporary */
3784d9c625SLionel Sambuc#ifndef __ARM_EABI__
3884d9c625SLionel Sambuc	mov	r3, r2
3984d9c625SLionel Sambuc	mov	r2, r1
4084d9c625SLionel Sambuc#endif
4184d9c625SLionel Sambuc	mov	ip, r0			/* need r0 for return value */
4284d9c625SLionel Sambuc1:	ldrexd	r0, r1, [ip]		/* load old value */
4384d9c625SLionel Sambuc	eors	r0, r0, r2		/* calculate new value (return value) */
4484d9c625SLionel Sambuc	eors	r1, r1, r3		/* calculate new value (return value) */
4584d9c625SLionel Sambuc	strexd	r4, r0, r1, [ip]	/* try to store */
4684d9c625SLionel Sambuc	cmp	r4, #0			/*   succeed? */
4784d9c625SLionel Sambuc	bne	1b			/*     no, try again? */
4884d9c625SLionel Sambuc#ifdef _ARM_ARCH_7
4984d9c625SLionel Sambuc	dmb
5084d9c625SLionel Sambuc#else
5184d9c625SLionel Sambuc	mcr	p15, 0, r4, c7, c10, 5	/* data memory barrier */
5284d9c625SLionel Sambuc#endif
5384d9c625SLionel Sambuc	pop	{r3,r4}			/* restore temporary */
5484d9c625SLionel Sambuc	RET				/* return new value */
5584d9c625SLionel SambucEND(_atomic_xor_64_nv)
5684d9c625SLionel Sambuc
5784d9c625SLionel SambucSTRONG_ALIAS(_atomic_xor_64,_atomic_xor_64_nv)
5884d9c625SLionel SambucATOMIC_OP_ALIAS(atomic_xor_64_nv,_atomic_xor_64_nv)
5984d9c625SLionel SambucATOMIC_OP_ALIAS(atomic_xor_64,_atomic_xor_64)
60*0a6a1f1dSLionel SambucCRT_ALIAS(__sync_xor_and_fetch_8,_atomic_xor_64)
6184d9c625SLionel Sambuc
6284d9c625SLionel Sambuc#endif /* _ARM_ARCH_6 */
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