/*      $NetBSD: atomic_cas.S,v 1.9 2022/02/27 19:21:53 riastradh Exp $ */

/*-
 * Copyright (c) 2008 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * 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 <machine/asm.h>
#include "atomic_op_asm.h"

RCSID("$NetBSD: atomic_cas.S,v 1.9 2022/02/27 19:21:53 riastradh Exp $")

        .text
        .set    noat
        .set    noreorder
        .set    nomacro

LEAF(_atomic_cas_32)
        LLSCSYNC
1:      INT_LL          v0, 0(a0)
         nop
        bne             v0, a1, 2f
         nop
        move            t0, a2
        INT_SC          t0, 0(a0)
        beq             t0, zero, 1b
         nop
        move            v0, a1
        SYNC_PLUNGER
2:
        j               ra
         nop
END(_atomic_cas_32)
ATOMIC_OP_ALIAS(atomic_cas_32, _atomic_cas_32)
ATOMIC_OP_ALIAS(atomic_cas_32_ni, _atomic_cas_32)

#if !defined(__mips_o32)
LEAF(_atomic_cas_64)
        LLSCSYNC
1:      REG_LL          v0, 0(a0)
         nop
        bne             v0, a1, 2f
         nop
        move            t0, a2
        REG_SC          t0, 0(a0)
        beq             t0, zero, 1b
         nop
        move            v0, a1
        SYNC_PLUNGER
2:
        j               ra
         nop
END(_atomic_cas_64)
ATOMIC_OP_ALIAS(atomic_cas_64, _atomic_cas_64)
ATOMIC_OP_ALIAS(atomic_cas_64_ni, _atomic_cas_64)
#endif

#ifdef _LP64
STRONG_ALIAS(_atomic_cas_ptr,           _atomic_cas_64)
STRONG_ALIAS(_atomic_cas_ptr_ni,        _atomic_cas_64)
STRONG_ALIAS(_atomic_cas_ulong,         _atomic_cas_64)
STRONG_ALIAS(_atomic_cas_ulong_ni,      _atomic_cas_64)
#else
STRONG_ALIAS(_atomic_cas_ptr,           _atomic_cas_32)
STRONG_ALIAS(_atomic_cas_ptr_ni,        _atomic_cas_32)
STRONG_ALIAS(_atomic_cas_ulong,         _atomic_cas_32)
STRONG_ALIAS(_atomic_cas_ulong_ni,      _atomic_cas_32)
#endif
STRONG_ALIAS(_atomic_cas_uint,          _atomic_cas_32)
STRONG_ALIAS(_atomic_cas_uint_ni,       _atomic_cas_32)

ATOMIC_OP_ALIAS(atomic_cas_ptr,         _atomic_cas_ptr)
ATOMIC_OP_ALIAS(atomic_cas_ptr_ni,      _atomic_cas_ptr_ni)
ATOMIC_OP_ALIAS(atomic_cas_uint,        _atomic_cas_uint)
ATOMIC_OP_ALIAS(atomic_cas_uint_ni,     _atomic_cas_uint_ni)
ATOMIC_OP_ALIAS(atomic_cas_ulong,       _atomic_cas_ulong)
ATOMIC_OP_ALIAS(atomic_cas_ulong_ni,    _atomic_cas_ulong_ni)