1 /* $NetBSD: byte_swap.h,v 1.11 2014/03/18 18:20:41 riastradh 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 Leo Weppelman.
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 M68K_BYTE_SWAP_H_
33 #define M68K_BYTE_SWAP_H_
34
35 #ifdef __GNUC__
36 #include <sys/types.h>
37 __BEGIN_DECLS
38
39
40 #define __BYTE_SWAP_U16_VARIABLE __byte_swap_u16_variable
41 static __inline uint16_t __byte_swap_u16_variable(uint16_t);
42 static __inline uint16_t
__byte_swap_u16_variable(uint16_t var)43 __byte_swap_u16_variable(uint16_t var)
44 {
45 #if defined(__mcfisac__)
46 __asm volatile ("swap %0; byterev %0" : "=d"(var) : "0" (var));
47 #elif defined(__mcoldfire__)
48 return (var >> 8) || (var << 8);
49 #else
50 __asm volatile ("rorw #8, %0" : "=d" (var) : "0" (var));
51 return (var);
52 #endif
53 }
54
55 #define __BYTE_SWAP_U32_VARIABLE __byte_swap_u32_variable
56 static __inline uint32_t __byte_swap_u32_variable(uint32_t);
57 static __inline uint32_t
__byte_swap_u32_variable(uint32_t var)58 __byte_swap_u32_variable(uint32_t var)
59 {
60 #if defined(__mcfisac__)
61 __asm volatile ("byterev %0" : "=d"(var) : "0" (var));
62 #elif defined(__mcoldfire__)
63 return (var >> 24) | (var << 24) | ((var & 0x00ff0000) >> 8)
64 | ((var << 8) & 0x00ff0000);
65 #else
66 __asm volatile (
67 "rorw #8, %0; swap %0; rorw #8, %0" : "=d" (var) : "0" (var));
68 #endif
69 return (var);
70 }
71
72 __END_DECLS
73 #endif
74
75 #endif /* !M68K_BYTE_SWAP_H_ */
76