xref: /freebsd/sys/powerpc/include/endian.h (revision 7660b554bc59a07be0431c17e0e33815818baa69)
1 /*-
2  * Copyright (c) 1987, 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)endian.h	8.1 (Berkeley) 6/10/93
34  *	$NetBSD: endian.h,v 1.7 1999/08/21 05:53:51 simonb Exp $
35  * $FreeBSD$
36  */
37 
38 #ifndef _MACHINE_ENDIAN_H_
39 #define	_MACHINE_ENDIAN_H_
40 
41 #include <sys/cdefs.h>
42 #include <sys/_types.h>
43 
44 /*
45  * Define the order of 32-bit words in 64-bit words.
46  */
47 #define	_QUAD_HIGHWORD 0
48 #define	_QUAD_LOWWORD 1
49 
50 /*
51  * Definitions for byte order, according to byte significance from low
52  * address to high.
53  */
54 #undef  _BIG_ENDIAN		/* GCC annoyingly defines this for PowerPC */
55 #define	_LITTLE_ENDIAN	1234	/* LSB first: i386, vax */
56 #define	_BIG_ENDIAN	4321	/* MSB first: 68000, ibm, net */
57 #define	_PDP_ENDIAN	3412	/* LSB first in word, MSW first in long */
58 
59 #define	_BYTE_ORDER	_BIG_ENDIAN
60 
61 /*
62  * Deprecated variants that don't have enough underscores to be useful in more
63  * strict namespaces.
64  */
65 #if __BSD_VISIBLE
66 #define	LITTLE_ENDIAN	_LITTLE_ENDIAN
67 #define	BIG_ENDIAN	_BIG_ENDIAN
68 #define	PDP_ENDIAN	_PDP_ENDIAN
69 #define	BYTE_ORDER	_BYTE_ORDER
70 #endif
71 
72 #ifdef __GNUC__
73 
74 static __inline __uint16_t
75 __bswap16(__uint16_t _x)
76 {
77 
78 	return ((_x >> 8) | ((_x << 8) & 0xff00));
79 }
80 
81 static __inline __uint32_t
82 __bswap32(__uint32_t _x)
83 {
84 
85 	return ((_x >> 24) | ((_x >> 8) & 0xff00) | ((_x << 8) & 0xff0000) |
86 	    ((_x << 24) & 0xff000000));
87 }
88 
89 static __inline __uint64_t
90 __bswap64(__uint64_t _x)
91 {
92 
93 	return ((_x >> 56) | ((_x >> 40) & 0xff00) | ((_x >> 24) & 0xff0000) |
94 	    ((_x >> 8) & 0xff000000) | ((_x << 8) & ((__uint64_t)0xff << 32)) |
95 	    ((_x << 24) & ((__uint64_t)0xff << 40)) |
96 	    ((_x << 40) & ((__uint64_t)0xff << 48)) | ((_x << 56)));
97 }
98 
99 #define	__htonl(x)	((__uint32_t)(x))
100 #define	__htons(x)	((__uint16_t)(x))
101 #define	__ntohl(x)	((__uint32_t)(x))
102 #define	__ntohs(x)	((__uint16_t)(x))
103 
104 #else /* !__GNUC__ */
105 
106 /*
107  * No optimizations are available for this compiler.  Fall back to
108  * non-optimized functions by defining the constant usually used to prevent
109  * redefinition.
110  */
111 #define	_BYTEORDER_FUNC_DEFINED
112 
113 #endif /* __GNUC__ */
114 
115 #endif /* !_MACHINE_ENDIAN_H_ */
116