1/*	$NetBSD: compiler.h,v 1.9 2022/07/17 08:34:00 riastradh Exp $	*/
2
3/*-
4 * Copyright (c) 2018 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Taylor R. Campbell.
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#ifndef	_LINUX_COMPILER_H_
33#define	_LINUX_COMPILER_H_
34
35#include <sys/atomic.h>
36#include <sys/cdefs.h>
37
38#include <linux/stddef.h>
39
40#include <asm/barrier.h>
41
42#define	__printf	__printflike
43#define	__user
44#if __GNUC_PREREQ__(4,0)	/* not sure when but this will work */
45#define	__must_check	__attribute__((warn_unused_result))
46#else
47#define	__must_check	/* nothing */
48#endif
49#define	__always_unused	__unused
50#define	__maybe_unused	__unused
51#define	noinline	__noinline
52#define	__deprecated	/* nothing */
53#define	__acquire(X)	/* nothing */
54#define	__release(X)	/* nothing */
55
56#define	barrier()	__insn_barrier()
57#define	likely(X)	__predict_true(X)
58#define	unlikely(X)	__predict_false(X)
59#define	__same_type(X,Y)						      \
60	__builtin_types_compatible_p(__typeof__(X), __typeof__(Y))
61#define	__must_be_array(X)						      \
62	BUILD_BUG_ON_ZERO(__same_type((X), &(X)[0]))
63
64#define	READ_ONCE(X)	({						      \
65	__insn_barrier();						      \
66	typeof(X) __read_once_tmp = (X);				      \
67	membar_datadep_consumer();					      \
68	__read_once_tmp;						      \
69})
70
71#define	WRITE_ONCE(X, V)	({					      \
72	typeof(X) __write_once_tmp = (V);				      \
73	__insn_barrier();						      \
74	(X) = __write_once_tmp;						      \
75	__insn_barrier();						      \
76	__write_once_tmp;						      \
77})
78
79#define	smp_store_mb(X, V)	do {					      \
80	WRITE_ONCE(X, V);						      \
81	smp_mb();							      \
82} while (0)
83
84#define	smp_store_release(X, V)	do {					      \
85	typeof(X) __smp_store_release_tmp = (V);			      \
86	membar_release();						      \
87	(X) = __write_once_tmp;						      \
88} while (0)
89
90#endif	/* _LINUX_COMPILER_H_ */
91