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Revision: 1.39
Committed: Sat Jun 11 14:18:49 2011 UTC (13 years ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.38: +30 -28 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 1.39 #define ECB_C99 (__STDC_VERSION__ >= 199901L)
51    
52     #if __cplusplus
53 root 1.38 #define ECB_INLINE static inline
54     #elif ECB_GCC_VERSION(2,5)
55     #define ECB_INLINE static __inline__
56 root 1.39 #elif ECB_C99
57 root 1.38 #define ECB_INLINE static inline
58 root 1.29 #else
59 root 1.38 #define ECB_INLINE static
60     #endif
61    
62     #if ECB_GCC_VERSION(3,3)
63     #define ecb_restrict __restrict__
64 root 1.39 #elif ECB_C99
65 root 1.38 #define ecb_restrict restrict
66     #else
67     #define ecb_restrict
68 root 1.4 #endif
69    
70 root 1.38 typedef int ecb_bool;
71    
72 root 1.8 #define ECB_CONCAT_(a, b) a ## b
73     #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
74     #define ECB_STRINGIFY_(a) # a
75     #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
76    
77 root 1.39 #define ecb_function_ ECB_INLINE
78 root 1.3
79 root 1.1 #if ECB_GCC_VERSION(3,1)
80 root 1.37 #define ecb_attribute(attrlist) __attribute__(attrlist)
81     #define ecb_is_constant(expr) __builtin_constant_p (expr)
82     #define ecb_expect(expr,value) __builtin_expect ((expr),(value))
83     #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
84     #else
85     #define ecb_attribute(attrlist)
86     #define ecb_is_constant(expr) 0
87     #define ecb_expect(expr,value) (expr)
88     #define ecb_prefetch(addr,rw,locality)
89 root 1.1 #endif
90    
91 root 1.2 /* no emulation for ecb_decltype */
92 root 1.1 #if ECB_GCC_VERSION(4,5)
93 root 1.37 #define ecb_decltype(x) __decltype(x)
94 root 1.1 #elif ECB_GCC_VERSION(3,0)
95 root 1.39 #define ecb_decltype(x) __typeof(x)
96 root 1.1 #endif
97    
98 root 1.24 #define ecb_noinline ecb_attribute ((__noinline__))
99     #define ecb_noreturn ecb_attribute ((__noreturn__))
100     #define ecb_unused ecb_attribute ((__unused__))
101     #define ecb_const ecb_attribute ((__const__))
102     #define ecb_pure ecb_attribute ((__pure__))
103 root 1.35
104     #if ECB_GCC_VERSION(4,3)
105 root 1.39 #define ecb_artificial ecb_attribute ((__artificial__))
106     #define ecb_hot ecb_attribute ((__hot__))
107     #define ecb_cold ecb_attribute ((__cold__))
108 root 1.35 #else
109     #define ecb_artificial
110     #define ecb_hot
111     #define ecb_cold
112     #endif
113 root 1.1
114 root 1.39 /* put around conditional expressions if you are very sure that the */
115     /* expression is mostly true or mostly false. note that these return */
116     /* booleans, not the expression. */
117 root 1.33 #define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
118     #define ecb_expect_true(expr) ecb_expect (!!(expr), 1)
119 root 1.36 /* for compatibility to the rest of the world */
120 root 1.33 #define ecb_likely(expr) ecb_expect_true (expr)
121     #define ecb_unlikely(expr) ecb_expect_false (expr)
122 root 1.1
123 root 1.3 /* try to tell the compiler that some condition is definitely true */
124 root 1.19 #define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0)
125 root 1.1
126 root 1.3 /* count trailing zero bits and count # of one bits */
127 root 1.1 #if ECB_GCC_VERSION(3,4)
128 root 1.35 #define ecb_ctz32(x) __builtin_ctz (x)
129     #define ecb_popcount32(x) __builtin_popcount (x)
130 root 1.1 #else
131 root 1.39 ecb_function_ int ecb_ctz32 (uint32_t x) ecb_const;
132     ecb_function_ int
133 root 1.35 ecb_ctz32 (uint32_t x)
134     {
135     int r = 0;
136    
137     x &= -x; /* this isolates the lowest bit */
138    
139     if (x & 0xaaaaaaaa) r += 1;
140     if (x & 0xcccccccc) r += 2;
141     if (x & 0xf0f0f0f0) r += 4;
142     if (x & 0xff00ff00) r += 8;
143     if (x & 0xffff0000) r += 16;
144    
145     return r;
146     }
147    
148 root 1.39 ecb_function_ int ecb_popcount32 (uint32_t x) ecb_const;
149     ecb_function_ int
150 root 1.35 ecb_popcount32 (uint32_t x)
151     {
152     x -= (x >> 1) & 0x55555555;
153     x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
154     x = ((x >> 4) + x) & 0x0f0f0f0f;
155     x *= 0x01010101;
156 root 1.1
157 root 1.35 return x >> 24;
158     }
159 root 1.1 #endif
160    
161 root 1.13 #if ECB_GCC_VERSION(4,3)
162 root 1.35 #define ecb_bswap32(x) __builtin_bswap32 (x)
163     #define ecb_bswap16(x) (__builtin_bswap32(x) >> 16)
164 root 1.13 #else
165 root 1.39 ecb_function_ uint32_t ecb_bswap32 (uint32_t x) ecb_const;
166     ecb_function_ uint32_t
167 root 1.35 ecb_bswap32 (uint32_t x)
168     {
169     return (x >> 24)
170     | ((x >> 8) & 0x0000ff00)
171     | ((x << 8) & 0x00ff0000)
172     | (x << 24);
173     }
174    
175 root 1.39 ecb_function_ uint32_t ecb_bswap16 (uint32_t x) ecb_const;
176     ecb_function_ uint32_t
177 root 1.35 ecb_bswap16 (uint32_t x)
178     {
179     return ((x >> 8) & 0xff)
180     | ((x << 8) & 0x00ff0000)
181     | (x << 24);
182     }
183 root 1.13 #endif
184    
185     #if ECB_GCC_VERSION(4,5)
186 root 1.35 #define ecb_unreachable() __builtin_unreachable ()
187 root 1.13 #else
188 root 1.35 /* this seems to work fine, but gcc always emits a warning for it :/ */
189 root 1.39 ecb_function_ void ecb_unreachable (void) ecb_noreturn;
190     ecb_function_ void ecb_unreachable (void) { }
191 root 1.13 #endif
192    
193 root 1.39 ecb_function_ unsigned char ecb_byteorder_helper (void) ecb_const;
194     ecb_function_ unsigned char
195 root 1.23 ecb_byteorder_helper (void)
196 root 1.3 {
197     const uint32_t u = 0x11223344;
198     return *(unsigned char *)&u;
199     }
200    
201 root 1.39 ecb_function_ ecb_bool ecb_big_endian (void) ecb_const;
202     ecb_function_ ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; };
203     ecb_function_ ecb_bool ecb_little_endian (void) ecb_const;
204     ecb_function_ ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; };
205 root 1.3
206 root 1.39 #if ECB_GCC_VERSION(3,0) || ECB_C99
207 root 1.35 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
208 root 1.31 #else
209 root 1.35 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
210 root 1.31 #endif
211 root 1.21
212 root 1.5 #if ecb_cplusplus_does_not_suck
213 root 1.35 // does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm)
214     template<typename T, int N>
215     static inline int ecb_array_length (const T (&arr)[N])
216     {
217     return N;
218     }
219 root 1.5 #else
220 root 1.35 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
221 root 1.5 #endif
222    
223 root 1.14 ECB_INLINE uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
224 root 1.6 ECB_INLINE uint32_t
225 root 1.9 ecb_rotr32 (uint32_t x, unsigned int count)
226 root 1.6 {
227 root 1.9 return (x << (32 - count)) | (x >> count);
228 root 1.6 }
229    
230 root 1.14 ECB_INLINE uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
231 root 1.6 ECB_INLINE uint32_t
232 root 1.9 ecb_rotl32 (uint32_t x, unsigned int count)
233 root 1.6 {
234 root 1.9 return (x >> (32 - count)) | (x << count);
235 root 1.6 }
236    
237 root 1.1 #endif
238