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Revision: 1.32
Committed: Wed Jun 1 01:02:31 2011 UTC (13 years ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.31: +1 -1 lines
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# Content
1 /*
2 * libecb - http://software.schmorp.de/pkg/libecb
3 *
4 * Copyright (©) 2009-2011 Marc Alexander Lehmann <libecb@schmorp.de>
5 * Copyright (©) 2011 Emanuele Giaquinta
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without modifica-
9 * tion, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright notice,
12 * this list of conditions and the following disclaimer.
13 *
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
19 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
20 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
21 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
22 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
23 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
24 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
25 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
26 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
27 * OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30 #ifndef ECB_H
31 #define ECB_H
32
33 #include <inttypes.h>
34
35 /* many compilers define _GNUC_ to some versions but then only implement
36 * what their idiot authors think are the "more important" extensions,
37 * causing enourmous grief in return for some better fake benchmark numbers.
38 * or so.
39 * we try to detect these and simply assume they are not gcc - if they have
40 * an issue with that they should have done it right in the first place.
41 */
42 #ifndef ECB_GCC_VERSION
43 # if defined(__INTEL_COMPILER) || defined(__SUNPRO_C) || defined(__llvm__)
44 # define ECB_GCC_VERSION(major,minor) 0
45 # else
46 # define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
47 # endif
48 #endif
49
50 #ifndef __cplusplus
51 # if __STDC_VERSION__ >= 199901L
52 # define ECB_INLINE inline
53 typedef _Bool ecb_bool;
54 # else
55 # define ECB_INLINE inline /* yeah! */
56 typedef int ecb_bool;
57 # endif
58 #else
59 # define ECB_INLINE inline
60 typedef bool ecb_bool;
61 #endif
62
63 #define ECB_CONCAT_(a, b) a ## b
64 #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
65 #define ECB_STRINGIFY_(a) # a
66 #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
67
68 #define ECB_HEADER_INLINE static ECB_INLINE
69
70 #if ECB_GCC_VERSION(3,1)
71 # define ecb_attribute(attrlist) __attribute__(attrlist)
72 # define ecb_is_constant(expr) __builtin_constant_p (expr)
73 # define ecb_expect(expr,value) __builtin_expect ((expr),(value))
74 # define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
75 #else
76 # define ecb_attribute(attrlist)
77 # define ecb_is_constant(expr) 0
78 # define ecb_expect(expr,value) (expr)
79 # define ecb_prefetch(addr,rw,locality)
80 #endif
81
82 /* no emulation for ecb_decltype */
83 #if ECB_GCC_VERSION(4,5)
84 # define ecb_decltype(x) __decltype(x)
85 #elif ECB_GCC_VERSION(3,0)
86 # define ecb_decltype(x) typeof(x)
87 #endif
88
89 #define ecb_artificial ecb_attribute ((__artificial__)) /* 4.3 */
90 #define ecb_noinline ecb_attribute ((__noinline__))
91 #define ecb_noreturn ecb_attribute ((__noreturn__))
92 #define ecb_unused ecb_attribute ((__unused__))
93 #define ecb_const ecb_attribute ((__const__))
94 #define ecb_pure ecb_attribute ((__pure__))
95 #define ecb_hot ecb_attribute ((__hot__)) /* 4.3 */
96 #define ecb_cold ecb_attribute ((__cold__)) /* 4.3 */
97
98 /* put into if's if you are very sure that the expression */
99 /* is mostly true or mosty false. note that these return */
100 /* booleans, not the expression. */
101 #define ecb_unlikely(expr) ecb_expect (!!(expr), 0)
102 #define ecb_likely(expr) ecb_expect (!!(expr), 1)
103
104 /* try to tell the compiler that some condition is definitely true */
105 #define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0)
106
107 /* count trailing zero bits and count # of one bits */
108 #if ECB_GCC_VERSION(3,4)
109 #define ecb_ctz32(x) __builtin_ctz (x)
110 #define ecb_popcount32(x) __builtin_popcount (x)
111 #else
112 ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) ecb_const;
113 ECB_HEADER_INLINE
114 ecb_ctz32 (uint32_t x)
115 {
116 int r = 0;
117
118 x &= -x; /* this isolates the lowest bit */
119
120 if (x & 0xaaaaaaaa) r += 1;
121 if (x & 0xcccccccc) r += 2;
122 if (x & 0xf0f0f0f0) r += 4;
123 if (x & 0xff00ff00) r += 8;
124 if (x & 0xffff0000) r += 16;
125
126 return r;
127 }
128
129 ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) ecb_const;
130 ECB_HEADER_INLINE
131 ecb_popcount32 (uint32_t x)
132 {
133 x -= (x >> 1) & 0x55555555;
134 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
135 x = ((x >> 4) + x) & 0x0f0f0f0f;
136 x *= 0x01010101;
137
138 return x >> 24;
139 }
140 #endif
141
142 #if ECB_GCC_VERSION(4,3)
143 # define ecb_bswap32(x) __builtin_bswap32 (x)
144 # define ecb_bswap16(x) (__builtin_bswap32(x) >> 16)
145 #else
146 ECB_HEADER_INLINE uint32_t ecb_bswap32 (uint32_t x) ecb_const;
147 ECB_HEADER_INLINE uint32_t
148 ecb_bswap32 (uint32_t x)
149 {
150 return (x >> 24)
151 | ((x >> 8) & 0x0000ff00)
152 | ((x << 8) & 0x00ff0000)
153 | (x << 24);
154 }
155
156 ECB_HEADER_INLINE uint32_t ecb_bswap16 (uint32_t x) ecb_const;
157 ECB_HEADER_INLINE uint32_t
158 ecb_bswap16 (uint32_t x)
159 {
160 return ((x >> 8) & 0xff)
161 | ((x << 8) & 0x00ff0000)
162 | (x << 24);
163 }
164 #endif
165
166 #if ECB_GCC_VERSION(4,5)
167 # define ecb_unreachable() __builtin_unreachable ()
168 #else
169 /* this seems to work fine, but gcc always emits a warning for it :/ */
170 ECB_HEADER_INLINE void ecb_unreachable (void) ecb_noreturn;
171 ECB_HEADER_INLINE void ecb_unreachable (void) { }
172 #endif
173
174 ECB_HEADER_INLINE unsigned char ecb_byteorder_helper (void) ecb_const;
175 ECB_HEADER_INLINE unsigned char
176 ecb_byteorder_helper (void)
177 {
178 const uint32_t u = 0x11223344;
179 return *(unsigned char *)&u;
180 }
181
182 ECB_HEADER_INLINE ecb_bool ecb_big_endian (void) ecb_const;
183 ECB_HEADER_INLINE ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; };
184 ECB_HEADER_INLINE ecb_bool ecb_little_endian (void) ecb_const;
185 ECB_HEADER_INLINE ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; };
186
187 #if ECB_GCC_VERSION(3,0)
188 # define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
189 #else
190 # define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
191 #endif
192
193 #if ecb_cplusplus_does_not_suck
194 // does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
195 template<typename T, int N>
196 static inline int ecb_array_length (const T (&arr)[N])
197 {
198 return N;
199 }
200 #else
201 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
202 #endif
203
204 ECB_INLINE uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
205 ECB_INLINE uint32_t
206 ecb_rotr32 (uint32_t x, unsigned int count)
207 {
208 return (x << (32 - count)) | (x >> count);
209 }
210
211 ECB_INLINE uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
212 ECB_INLINE uint32_t
213 ecb_rotl32 (uint32_t x, unsigned int count)
214 {
215 return (x >> (32 - count)) | (x << count);
216 }
217
218 #endif
219