2 * Copyright (c) 2001 Daniel Eischen <deischen@FreeBSD.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Neither the name of the author nor the names of its contributors
11 * may be used to endorse or promote products derived from this software
12 * without specific prior written permission.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 #ifndef _ATOMIC_OPS_H_
30 #define _ATOMIC_OPS_H_
34 * Atomic (tmp = *dst, *dst = val), then *res = tmp
36 * void atomic_swap64(intptr_t *dst, intptr_t val, intptr_t *res);
39 atomic_swap64(volatile intptr_t *dst, intptr_t val, intptr_t *res)
42 "xchgq %2, %1; movq %2, %0"
43 : "=m" (*res) : "m" (*dst), "r" (val) : "memory");
47 atomic_swap_int(volatile int *dst, int val, int *res)
50 "xchgl %2, %1; movl %2, %0"
51 : "=m" (*res) : "m" (*dst), "r" (val) : "memory");
54 #define atomic_swap_ptr(d, v, r) \
55 atomic_swap64((volatile intptr_t *)(d), (intptr_t)(v), (intptr_t *)(r))