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Revision: 1.38
Committed: Sat Jun 11 14:02:40 2011 UTC (13 years ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.37: +17 -10 lines
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# User Rev Content
1 root 1.1 /*
2 root 1.17 * libecb - http://software.schmorp.de/pkg/libecb
3 root 1.1 *
4 root 1.30 * Copyright (©) 2009-2011 Marc Alexander Lehmann <libecb@schmorp.de>
5 root 1.7 * Copyright (©) 2011 Emanuele Giaquinta
6 root 1.1 * 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 root 1.6 #include <inttypes.h>
34    
35 root 1.12 /* many compilers define _GNUC_ to some versions but then only implement
36     * what their idiot authors think are the "more important" extensions,
37 root 1.18 * causing enourmous grief in return for some better fake benchmark numbers.
38     * or so.
39 root 1.12 * 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 root 1.14 #ifndef ECB_GCC_VERSION
43 root 1.37 #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 root 1.12 #endif
49 root 1.1
50 root 1.38 #ifdef __cplusplus
51     #define ECB_INLINE static inline
52     #elif ECB_GCC_VERSION(2,5)
53     #define ECB_INLINE static __inline__
54     #elif __STDC_VERSION__ >= 199901L
55     #define ECB_INLINE static inline
56 root 1.29 #else
57 root 1.38 #define ECB_INLINE static
58     #endif
59    
60     #if ECB_GCC_VERSION(3,3)
61     #define ecb_restrict __restrict__
62     #elif __STDC_VERSION__ >= 199901L
63     #define ecb_restrict restrict
64     #else
65     #define ecb_restrict
66 root 1.4 #endif
67    
68 root 1.38 typedef int ecb_bool;
69    
70 root 1.8 #define ECB_CONCAT_(a, b) a ## b
71     #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
72     #define ECB_STRINGIFY_(a) # a
73     #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
74    
75 root 1.34 #define ECB_HEADER_INLINE ECB_INLINE
76 root 1.3
77 root 1.1 #if ECB_GCC_VERSION(3,1)
78 root 1.37 #define ecb_attribute(attrlist) __attribute__(attrlist)
79     #define ecb_is_constant(expr) __builtin_constant_p (expr)
80     #define ecb_expect(expr,value) __builtin_expect ((expr),(value))
81     #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
82     #else
83     #define ecb_attribute(attrlist)
84     #define ecb_is_constant(expr) 0
85     #define ecb_expect(expr,value) (expr)
86     #define ecb_prefetch(addr,rw,locality)
87 root 1.1 #endif
88    
89 root 1.2 /* no emulation for ecb_decltype */
90 root 1.1 #if ECB_GCC_VERSION(4,5)
91 root 1.37 #define ecb_decltype(x) __decltype(x)
92 root 1.1 #elif ECB_GCC_VERSION(3,0)
93 root 1.37 #define ecb_decltype(x) typeof(x)
94 root 1.1 #endif
95    
96 root 1.24 #define ecb_noinline ecb_attribute ((__noinline__))
97     #define ecb_noreturn ecb_attribute ((__noreturn__))
98     #define ecb_unused ecb_attribute ((__unused__))
99     #define ecb_const ecb_attribute ((__const__))
100     #define ecb_pure ecb_attribute ((__pure__))
101 root 1.35
102     #if ECB_GCC_VERSION(4,3)
103     #define ecb_artificial ecb_attribute ((__artificial__)) /* 4.3 */
104     #define ecb_hot ecb_attribute ((__hot__)) /* 4.3 */
105     #define ecb_cold ecb_attribute ((__cold__)) /* 4.3 */
106     #else
107     #define ecb_artificial
108     #define ecb_hot
109     #define ecb_cold
110     #endif
111 root 1.1
112 root 1.22 /* put into if's if you are very sure that the expression */
113 root 1.33 /* is mostly true or mostly false. note that these return */
114 root 1.3 /* booleans, not the expression. */
115 root 1.33 #define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
116     #define ecb_expect_true(expr) ecb_expect (!!(expr), 1)
117 root 1.36 /* for compatibility to the rest of the world */
118 root 1.33 #define ecb_likely(expr) ecb_expect_true (expr)
119     #define ecb_unlikely(expr) ecb_expect_false (expr)
120 root 1.1
121 root 1.3 /* try to tell the compiler that some condition is definitely true */
122 root 1.19 #define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0)
123 root 1.1
124 root 1.3 /* count trailing zero bits and count # of one bits */
125 root 1.1 #if ECB_GCC_VERSION(3,4)
126 root 1.35 #define ecb_ctz32(x) __builtin_ctz (x)
127     #define ecb_popcount32(x) __builtin_popcount (x)
128 root 1.1 #else
129 root 1.35 ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) ecb_const;
130     ECB_HEADER_INLINE int
131     ecb_ctz32 (uint32_t x)
132     {
133     int r = 0;
134    
135     x &= -x; /* this isolates the lowest bit */
136    
137     if (x & 0xaaaaaaaa) r += 1;
138     if (x & 0xcccccccc) r += 2;
139     if (x & 0xf0f0f0f0) r += 4;
140     if (x & 0xff00ff00) r += 8;
141     if (x & 0xffff0000) r += 16;
142    
143     return r;
144     }
145    
146     ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) ecb_const;
147     ECB_HEADER_INLINE int
148     ecb_popcount32 (uint32_t x)
149     {
150     x -= (x >> 1) & 0x55555555;
151     x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
152     x = ((x >> 4) + x) & 0x0f0f0f0f;
153     x *= 0x01010101;
154 root 1.1
155 root 1.35 return x >> 24;
156     }
157 root 1.1 #endif
158    
159 root 1.13 #if ECB_GCC_VERSION(4,3)
160 root 1.35 #define ecb_bswap32(x) __builtin_bswap32 (x)
161     #define ecb_bswap16(x) (__builtin_bswap32(x) >> 16)
162 root 1.13 #else
163 root 1.35 ECB_HEADER_INLINE uint32_t ecb_bswap32 (uint32_t x) ecb_const;
164     ECB_HEADER_INLINE uint32_t
165     ecb_bswap32 (uint32_t x)
166     {
167     return (x >> 24)
168     | ((x >> 8) & 0x0000ff00)
169     | ((x << 8) & 0x00ff0000)
170     | (x << 24);
171     }
172    
173     ECB_HEADER_INLINE uint32_t ecb_bswap16 (uint32_t x) ecb_const;
174     ECB_HEADER_INLINE uint32_t
175     ecb_bswap16 (uint32_t x)
176     {
177     return ((x >> 8) & 0xff)
178     | ((x << 8) & 0x00ff0000)
179     | (x << 24);
180     }
181 root 1.13 #endif
182    
183     #if ECB_GCC_VERSION(4,5)
184 root 1.35 #define ecb_unreachable() __builtin_unreachable ()
185 root 1.13 #else
186 root 1.35 /* this seems to work fine, but gcc always emits a warning for it :/ */
187     ECB_HEADER_INLINE void ecb_unreachable (void) ecb_noreturn;
188     ECB_HEADER_INLINE void ecb_unreachable (void) { }
189 root 1.13 #endif
190    
191 root 1.23 ECB_HEADER_INLINE unsigned char ecb_byteorder_helper (void) ecb_const;
192 root 1.3 ECB_HEADER_INLINE unsigned char
193 root 1.23 ecb_byteorder_helper (void)
194 root 1.3 {
195     const uint32_t u = 0x11223344;
196     return *(unsigned char *)&u;
197     }
198    
199 root 1.23 ECB_HEADER_INLINE ecb_bool ecb_big_endian (void) ecb_const;
200     ECB_HEADER_INLINE ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; };
201     ECB_HEADER_INLINE ecb_bool ecb_little_endian (void) ecb_const;
202     ECB_HEADER_INLINE ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; };
203 root 1.3
204 root 1.32 #if ECB_GCC_VERSION(3,0)
205 root 1.35 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
206 root 1.31 #else
207 root 1.35 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
208 root 1.31 #endif
209 root 1.21
210 root 1.5 #if ecb_cplusplus_does_not_suck
211 root 1.35 // does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
212     template<typename T, int N>
213     static inline int ecb_array_length (const T (&arr)[N])
214     {
215     return N;
216     }
217 root 1.5 #else
218 root 1.35 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
219 root 1.5 #endif
220    
221 root 1.14 ECB_INLINE uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
222 root 1.6 ECB_INLINE uint32_t
223 root 1.9 ecb_rotr32 (uint32_t x, unsigned int count)
224 root 1.6 {
225 root 1.9 return (x << (32 - count)) | (x >> count);
226 root 1.6 }
227    
228 root 1.14 ECB_INLINE uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
229 root 1.6 ECB_INLINE uint32_t
230 root 1.9 ecb_rotl32 (uint32_t x, unsigned int count)
231 root 1.6 {
232 root 1.9 return (x >> (32 - count)) | (x << count);
233 root 1.6 }
234    
235 root 1.1 #endif
236