xref: /dragonfly/sys/cpu/x86_64/include/endian.h (revision a563ca70)
1 /*-
2  * Copyright (c) 1987, 1991 Regents of the University of California.
3  * 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	7.8 (Berkeley) 4/3/91
34  * $FreeBSD: src/sys/amd64/include/endian.h,v 1.5 2003/09/22 22:37:49 peter Exp $
35  */
36 
37 #ifndef _CPU_ENDIAN_H_
38 #define	_CPU_ENDIAN_H_
39 
40 #ifndef _KERNEL
41 #include <sys/cdefs.h>
42 #endif
43 
44 #include <machine/stdint.h>
45 
46 /*
47  * Define the order of 32-bit words in 64-bit words.
48  */
49 #define	_QUAD_HIGHWORD 1
50 #define	_QUAD_LOWWORD 0
51 
52 /*
53  * Definitions for byte order, according to byte significance from low
54  * address to high.
55  */
56 #define	_LITTLE_ENDIAN	1234	/* LSB first: i386, vax */
57 #define	_BIG_ENDIAN	4321	/* MSB first: 68000, ibm, net */
58 #define	_PDP_ENDIAN	3412	/* LSB first in word, MSW first in long */
59 
60 #define	_BYTE_ORDER	_LITTLE_ENDIAN
61 
62 /*
63  * Deprecated variants that don't have enough underscores to be useful in more
64  * strict namespaces.
65  */
66 #if __BSD_VISIBLE
67 #define	LITTLE_ENDIAN	_LITTLE_ENDIAN
68 #define	BIG_ENDIAN	_BIG_ENDIAN
69 #define	PDP_ENDIAN	_PDP_ENDIAN
70 #define	BYTE_ORDER	_BYTE_ORDER
71 #endif
72 
73 #ifdef __GNUC__
74 
75 #define __word_swap_int_var(x) \
76 __extension__ ({ register __uint32_t __X = (x); \
77    __asm ("rorl $16, %0" : "+r" (__X)); \
78    __X; })
79 
80 #ifdef __OPTIMIZE__
81 
82 #define	__word_swap_int_const(x) \
83 	((((x) & 0xffff0000) >> 16) | \
84 	 (((x) & 0x0000ffff) << 16))
85 #define	__word_swap_int(x) (__builtin_constant_p(x) ? \
86 	__word_swap_int_const(x) : __word_swap_int_var(x))
87 
88 #else	/* __OPTIMIZE__ */
89 
90 #define	__word_swap_int(x) __word_swap_int_var(x)
91 
92 #endif	/* __OPTIMIZE__ */
93 
94 #define __byte_swap_int_var(x) \
95 __extension__ ({ register __uint32_t __X = (x); \
96    __asm ("bswap %0" : "+r" (__X)); \
97    __X; })
98 
99 #ifdef __OPTIMIZE__
100 
101 #define	__byte_swap_int_const(x) \
102 	((((x) & 0xff000000) >> 24) | \
103 	 (((x) & 0x00ff0000) >>  8) | \
104 	 (((x) & 0x0000ff00) <<  8) | \
105 	 (((x) & 0x000000ff) << 24))
106 #define	__byte_swap_int(x) (__builtin_constant_p(x) ? \
107 	__byte_swap_int_const(x) : __byte_swap_int_var(x))
108 
109 #else	/* __OPTIMIZE__ */
110 
111 #define	__byte_swap_int(x) __byte_swap_int_var(x)
112 
113 #endif	/* __OPTIMIZE__ */
114 
115 #define __byte_swap_long_var(x) \
116 __extension__ ({ register __uint64_t __X = (x); \
117    __asm ("bswap %0" : "+r" (__X)); \
118    __X; })
119 
120 #define	__byte_swap_long_const(x) \
121 	(((x >> 56) | \
122 	 ((x >> 40) & 0xff00) | \
123 	 ((x >> 24) & 0xff0000) | \
124 	 ((x >> 8) & 0xff000000) | \
125 	 ((x << 8) & ((__uint64_t)0xff << 32)) | \
126 	 ((x << 24) & ((__uint64_t)0xff << 40)) | \
127 	 ((x << 40) & ((__uint64_t)0xff << 48)) | \
128 	 ((x << 56))))
129 
130 #ifdef __i386__
131 
132 #define	__byte_swap_long(x)	__byte_swap_long_const(x)
133 
134 #else
135 
136 #ifdef __OPTIMIZE__
137 #define	__byte_swap_long(x)	(__builtin_constant_p(x) ? \
138 	__byte_swap_long_const(x) : __byte_swap_long_var(x))
139 #else	/* __OPTIMIZE__ */
140 #define	__byte_swap_long(x)	__byte_swap_long_var(x)
141 #endif	/* __OPTIMIZE__ */
142 
143 #endif	/* __i386__ */
144 
145 #define __byte_swap_word_var(x) \
146 __extension__ ({ register __uint16_t __X = (x); \
147    __asm ("xchgb %h0, %b0" : "+Q" (__X)); \
148    __X; })
149 
150 #ifdef __OPTIMIZE__
151 
152 #define	__byte_swap_word_const(x) \
153 	((((x) & 0xff00) >> 8) | \
154 	 (((x) & 0x00ff) << 8))
155 
156 #define	__byte_swap_word(x) (__builtin_constant_p(x) ? \
157 	__byte_swap_word_const(x) : __byte_swap_word_var(x))
158 
159 #else	/* __OPTIMIZE__ */
160 
161 #define	__byte_swap_word(x) __byte_swap_word_var(x)
162 
163 #endif	/* __OPTIMIZE__ */
164 
165 static __inline __uint64_t
166 __bswap64(__uint64_t _x)
167 {
168 
169 	return (__byte_swap_long(_x));
170 }
171 
172 static __inline __uint32_t
173 __bswap32(__uint32_t _x)
174 {
175 
176 	return (__byte_swap_int(_x));
177 }
178 
179 static __inline __uint16_t
180 __bswap16(__uint16_t _x)
181 {
182 
183 	return (__byte_swap_word(_x));
184 }
185 
186 #define	__htonl(x)	__bswap32(x)
187 #define	__htons(x)	__bswap16(x)
188 #define	__ntohl(x)	__bswap32(x)
189 #define	__ntohs(x)	__bswap16(x)
190 
191 #else /* !__GNUC__ */
192 
193 /*
194  * No optimizations are available for this compiler.  Fall back to
195  * non-optimized functions by defining the constant usually used to prevent
196  * redefinition.
197  */
198 #define	_BYTEORDER_FUNC_DEFINED
199 
200 #endif /* __GNUC__ */
201 
202 #endif /* !_CPU_ENDIAN_H_ */
203