xref: /openbsd-src/sys/arch/i386/include/endian.h (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /*	$OpenBSD: endian.h,v 1.12 2001/06/27 04:12:45 mickey Exp $	*/
2 
3 /*-
4  * Copyright (c) 1997 Niklas Hallqvist.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by Niklas Hallqvist.
17  * 4. The name of the author may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #ifndef _I386_ENDIAN_H_
33 #define _I386_ENDIAN_H_
34 
35 #ifdef __GNUC__
36 
37 #if defined(_KERNEL) && !defined(I386_CPU)
38 #define	__swap32md(x) ({						\
39 	u_int32_t __swap32md_x = (x);					\
40 									\
41 	__asm ("bswap %1" : "+r" (__swap32md_x));			\
42 	__swap32md_x;							\
43 })
44 #else
45 #define	__swap32md(x) ({						\
46 	u_int32_t __swap32md_x = (x);					\
47 									\
48 	__asm ("rorw $8, %w1; rorl $16, %1; rorw $8, %w1" :		\
49 	    "+r" (__swap32md_x));					\
50 	__swap32md_x;							\
51 })
52 #endif	/* _KERNEL && !I386_CPU */
53 
54 #define	__swap64md(x) ({						\
55 	u_int64_t __swap64md_x = (x);					\
56 									\
57 	(u_int64_t)__swap32md(__swap64md_x >> 32) |			\
58 	    (u_int64_t)__swap32md(__swap64md_x & 0xffffffff) << 32;	\
59 })
60 #define	__swap16md(x) ({						\
61 	u_int16_t __swap16md_x = (x);					\
62 									\
63 	__asm ("rorw $8, %w1" : "+r" (__swap16md_x));			\
64 	__swap16md_x;							\
65 })
66 
67 /* Tell sys/endian.h we have MD variants of the swap macros.  */
68 #define MD_SWAP
69 
70 #endif	/* __GNUC__ */
71 
72 #define BYTE_ORDER LITTLE_ENDIAN
73 #include <sys/endian.h>
74 
75 #endif /* _I386_ENDIAN_H_ */
76