1 /* $NetBSD: byte_swap.h,v 1.17 2020/08/10 10:59:33 rin Exp $ */
2
3 /*-
4 * Copyright (c) 1998 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Charles M. Hannum.
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 _I386_BYTE_SWAP_H_
33 #define _I386_BYTE_SWAP_H_
34
35 #include <sys/types.h>
36
37 #ifdef __GNUC__
38 __BEGIN_DECLS
39
40 #define __BYTE_SWAP_U32_VARIABLE __byte_swap_u32_variable
41 static __inline uint32_t __byte_swap_u32_variable(uint32_t);
42 static __inline uint32_t
__byte_swap_u32_variable(uint32_t x)43 __byte_swap_u32_variable(uint32_t x)
44 {
45 __asm volatile (
46 "bswap %1"
47 : "=r" (x) : "0" (x));
48 return (x);
49 }
50
51 #define __BYTE_SWAP_U16_VARIABLE __byte_swap_u16_variable
52 static __inline uint16_t __byte_swap_u16_variable(uint16_t);
53 static __inline uint16_t
__byte_swap_u16_variable(uint16_t x)54 __byte_swap_u16_variable(uint16_t x)
55 {
56 __asm volatile ("rorw $8, %w1" : "=r" (x) : "0" (x));
57 return (x);
58 }
59
60 __END_DECLS
61 #elif defined(_KERNEL)
62 #define __BYTE_SWAP_U32_VARIABLE __byte_swap_u32_variable
63 #define __BYTE_SWAP_U16_VARIABLE __byte_swap_u16_variable
64 uint32_t __byte_swap_u32_variable(uint32_t);
65 uint16_t __byte_swap_u16_variable(uint16_t);
66 #endif
67
68 #endif /* !_I386_BYTE_SWAP_H_ */
69