/* $NetBSD: atomic_cas_64.S,v 1.3.2.1 2021/08/11 17:19:01 martin Exp $ */ /*- * Copyright (c) 2014 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Matt Thomas of 3am Software Foundry. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include "atomic_op_asm.h" ENTRY_NP(_atomic_cas_64) mov x4, x0 /* we need r0 for return value */ 1: ldxr x0, [x4] /* load old value */ cmp x0, x1 /* compare? */ b.ne 2f /* return if different */ stxr w3, x2, [x4] /* store new value */ cbnz w3, 3f /* succeed? nope, try again. */ 2: ret /* return. */ 3: b 1b END(_atomic_cas_64) ATOMIC_OP_ALIAS(atomic_cas_64,_atomic_cas_64) ATOMIC_OP_ALIAS(atomic_cas_ulong,_atomic_cas_64) ATOMIC_OP_ALIAS(atomic_cas_ptr,_atomic_cas_64) ATOMIC_OP_ALIAS(atomic_cas_64_ni,_atomic_cas_64) ATOMIC_OP_ALIAS(atomic_cas_ulong_ni,_atomic_cas_64) ATOMIC_OP_ALIAS(atomic_cas_ptr_ni,_atomic_cas_64) STRONG_ALIAS(_atomic_cas_ulong,_atomic_cas_64) STRONG_ALIAS(_atomic_cas_ptr,_atomic_cas_64) STRONG_ALIAS(_atomic_cas_64_ni,_atomic_cas_64) STRONG_ALIAS(_atomic_cas_ulong_ni,_atomic_cas_64) STRONG_ALIAS(_atomic_cas_ptr_ni,_atomic_cas_64) ENTRY_NP(__sync_val_compare_and_swap_8) mov x4, x0 /* we need x0 for return value */ dmb ish 1: ldxr x0, [x4] /* load old value */ cmp x0, x1 /* compare? */ b.ne 2f /* return if different */ stxr w3, x2, [x4] /* store new value */ cbnz w3, 3f /* succeed? nope, try again. */ dmb ish 2: ret /* return. */ 3: b 1b END(__sync_val_compare_and_swap_8)