1/* $NetBSD: atomic_cas_64.S,v 1.1 2014/08/10 05:47:35 matt Exp $ */ 2 3/*- 4 * Copyright (c) 2014 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 of 3am Software Foundry. 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 34ENTRY_NP(_atomic_cas_64) 35 mov x4, x0 /* we need r0 for return value */ 361: ldxr x0, [x4] /* load old value */ 37 cmp x0, x1 /* compare? */ 38 b.ne 2f /* return if different */ 39 stxr w3, x2, [x4] /* store new value */ 40 cbnz w3, 1b /* succeed? nope, try again. */ 41 dmb st 422: ret /* return. */ 43END(_atomic_cas_64) 44 45ATOMIC_OP_ALIAS(atomic_cas_64,_atomic_cas_64) 46ATOMIC_OP_ALIAS(atomic_cas_ulong,_atomic_cas_64) 47ATOMIC_OP_ALIAS(atomic_cas_ptr,_atomic_cas_64) 48ATOMIC_OP_ALIAS(atomic_cas_ulong_ni,_atomic_cas_64) 49ATOMIC_OP_ALIAS(atomic_cas_ptr_ni,_atomic_cas_64) 50STRONG_ALIAS(__sync_val_compare_and_swap_8,_atomic_cas_64) 51STRONG_ALIAS(_atomic_cas_ulong,_atomic_cas_64) 52STRONG_ALIAS(_atomic_cas_64_ni,_atomic_cas_64) 53STRONG_ALIAS(_atomic_cas_ptr_ni,_atomic_cas_64) 54STRONG_ALIAS(_atomic_cas_ulong_ni,_atomic_cas_64) 55STRONG_ALIAS(_atomic_cas_ptr,_atomic_cas_64) 56