xref: /netbsd-src/common/lib/libc/arch/arm/atomic/atomic_add_32.S (revision a5847cc334d9a7029f6352b847e9e8d71a0f9e0c)
1/*	$NetBSD: atomic_add_32.S,v 1.2 2008/08/16 07:12:39 matt Exp $	*/
2
3/*-
4 * Copyright (c) 2008 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Matt Thomas <matt@3am-software.com>
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include "atomic_op_asm.h"
33
34#ifdef _ARM_ARCH_6
35
36ENTRY_NP(_atomic_add_32)
37	mov	r3, r0			/* need r0 for return value */
381:	ldrex	r0, [r3]		/* load old value (to be returned) */
39	add	r2, r0, r1		/* calculate new value */
40	strex	ip, r2, [r3]		/* try to store */
41	cmp	ip, #0			/*   succeed? */
42	bne	1b			/*     no, try again */
43	RET				/* return old value */
44	END(_atomic_add_32)
45ATOMIC_OP_ALIAS(atomic_add_32,_atomic_add_32)
46ATOMIC_OP_ALIAS(atomic_add_int,_atomic_add_32)
47ATOMIC_OP_ALIAS(atomic_add_long,_atomic_add_32)
48ATOMIC_OP_ALIAS(atomic_add_ptr,_atomic_add_32)
49STRONG_ALIAS(_atomic_add_int,_atomic_add_32)
50STRONG_ALIAS(_atomic_add_long,_atomic_add_32)
51STRONG_ALIAS(_atomic_add_ptr,_atomic_add_32)
52
53ENTRY_NP(_atomic_add_32_nv)
54	mov	r3, r0			/* need r0 for return value */
551:	ldrex	r0, [r3]		/* load old value */
56	add	r0, r0, r1		/* calculate new value (return value) */
57	strex	r2, r0, [r3]		/* try to store */
58	cmp	r2, #0			/*   succeed? */
59	bne	1b			/*     no, try again? */
60	RET				/* return new value */
61	END(_atomic_add_32_nv)
62ATOMIC_OP_ALIAS(atomic_add_32_nv,_atomic_add_32_nv)
63ATOMIC_OP_ALIAS(atomic_add_int_nv,_atomic_add_32_nv)
64ATOMIC_OP_ALIAS(atomic_add_long_nv,_atomic_add_32_nv)
65ATOMIC_OP_ALIAS(atomic_add_ptr_nv,_atomic_add_32_nv)
66STRONG_ALIAS(_atomic_add_int_nv,_atomic_add_32_nv)
67STRONG_ALIAS(_atomic_add_long_nv,_atomic_add_32_nv)
68STRONG_ALIAS(_atomic_add_ptr_nv,_atomic_add_32_nv)
69
70#endif /* _ARM_ARCH_6 */
71