xref: /openbsd-src/sys/arch/amd64/include/endian.h (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
1 /*	$OpenBSD: endian.h,v 1.3 2005/12/13 00:35:22 millert 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  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #ifndef _I386_ENDIAN_H_
28 #define _I386_ENDIAN_H_
29 
30 #ifdef __GNUC__
31 
32 #define	__swap32md(x) ({						\
33 	u_int32_t __swap32md_x = (x);					\
34 									\
35 	__asm ("bswap %1" : "+r" (__swap32md_x));			\
36 	__swap32md_x;							\
37 })
38 
39 /* XXX - I'm sure there is a better way on this cpu. */
40 #define	__swap64md(x) ({						\
41 	u_int64_t __swap64md_x = (x);					\
42 									\
43 	(u_int64_t)__swap32md(__swap64md_x >> 32) |			\
44 	    (u_int64_t)__swap32md(__swap64md_x & 0xffffffff) << 32;	\
45 })
46 
47 #define	__swap16md(x) ({						\
48 	u_int16_t __swap16md_x = (x);					\
49 									\
50 	__asm ("rorw $8, %w1" : "+r" (__swap16md_x));			\
51 	__swap16md_x;							\
52 })
53 
54 /* Tell sys/endian.h we have MD variants of the swap macros.  */
55 #define MD_SWAP
56 
57 #endif	/* __GNUC__ */
58 
59 #define _BYTE_ORDER _LITTLE_ENDIAN
60 #include <sys/endian.h>
61 
62 #endif /* _I386_ENDIAN_H_ */
63