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/cvs/libecb/ecb.h
Revision: 1.51
Committed: Wed Jun 22 15:18:06 2011 UTC (12 years, 11 months ago) by root
Content type: text/plain
Branch: MAIN
CVS Tags: rel-9_12
Changes since 1.50: +1 -1 lines
Log Message:
*** empty log message ***

File Contents

# 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 #ifdef _WIN32
34 typedef signed char int8_t;
35 typedef unsigned char uint8_t;
36 typedef signed short int16_t;
37 typedef unsigned short uint16_t;
38 typedef signed int int32_t;
39 typedef unsigned int uint32_t;
40 #if __GNUC__
41 typedef signed long long int64_t;
42 typedef unsigned long long uint64_t;
43 #else /* _MSC_VER || __BORLANDC__ */
44 typedef signed __int64 int64_t;
45 typedef unsigned __int64 uint64_t;
46 #endif
47 #else
48 #include <inttypes.h>
49 #endif
50
51 /* many compilers define _GNUC_ to some versions but then only implement
52 * what their idiot authors think are the "more important" extensions,
53 * causing enourmous grief in return for some better fake benchmark numbers.
54 * or so.
55 * we try to detect these and simply assume they are not gcc - if they have
56 * an issue with that they should have done it right in the first place.
57 */
58 #ifndef ECB_GCC_VERSION
59 #if !defined(__GNUC_MINOR__) || defined(__INTEL_COMPILER) || defined(__SUNPRO_C) || defined(__SUNPRO_CC) || defined(__llvm__) || defined(__clang__)
60 #define ECB_GCC_VERSION(major,minor) 0
61 #else
62 #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
63 #endif
64 #endif
65
66 #define ECB_C99 (__STDC_VERSION__ >= 199901L)
67
68 #if __cplusplus
69 #define ecb_inline static inline
70 #elif ECB_GCC_VERSION(2,5)
71 #define ecb_inline static __inline__
72 #elif ECB_C99
73 #define ecb_inline static inline
74 #else
75 #define ecb_inline static
76 #endif
77
78 #if ECB_GCC_VERSION(3,3)
79 #define ecb_restrict __restrict__
80 #elif ECB_C99
81 #define ecb_restrict restrict
82 #else
83 #define ecb_restrict
84 #endif
85
86 typedef int ecb_bool;
87
88 #define ECB_CONCAT_(a, b) a ## b
89 #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
90 #define ECB_STRINGIFY_(a) # a
91 #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
92
93 #define ecb_function_ ecb_inline
94
95 #if ECB_GCC_VERSION(3,1)
96 #define ecb_attribute(attrlist) __attribute__(attrlist)
97 #define ecb_is_constant(expr) __builtin_constant_p (expr)
98 #define ecb_expect(expr,value) __builtin_expect ((expr),(value))
99 #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
100 #else
101 #define ecb_attribute(attrlist)
102 #define ecb_is_constant(expr) 0
103 #define ecb_expect(expr,value) (expr)
104 #define ecb_prefetch(addr,rw,locality)
105 #endif
106
107 /* no emulation for ecb_decltype */
108 #if ECB_GCC_VERSION(4,5)
109 #define ecb_decltype(x) __decltype(x)
110 #elif ECB_GCC_VERSION(3,0)
111 #define ecb_decltype(x) __typeof(x)
112 #endif
113
114 #define ecb_noinline ecb_attribute ((__noinline__))
115 #define ecb_noreturn ecb_attribute ((__noreturn__))
116 #define ecb_unused ecb_attribute ((__unused__))
117 #define ecb_const ecb_attribute ((__const__))
118 #define ecb_pure ecb_attribute ((__pure__))
119
120 #if ECB_GCC_VERSION(4,3)
121 #define ecb_artificial ecb_attribute ((__artificial__))
122 #define ecb_hot ecb_attribute ((__hot__))
123 #define ecb_cold ecb_attribute ((__cold__))
124 #else
125 #define ecb_artificial
126 #define ecb_hot
127 #define ecb_cold
128 #endif
129
130 /* put around conditional expressions if you are very sure that the */
131 /* expression is mostly true or mostly false. note that these return */
132 /* booleans, not the expression. */
133 #define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
134 #define ecb_expect_true(expr) ecb_expect (!!(expr), 1)
135 /* for compatibility to the rest of the world */
136 #define ecb_likely(expr) ecb_expect_true (expr)
137 #define ecb_unlikely(expr) ecb_expect_false (expr)
138
139 /* count trailing zero bits and count # of one bits */
140 #if ECB_GCC_VERSION(3,4)
141 /* we assume int == 32 bit, long == 32 or 64 bit and long long == 64 bit */
142 #define ecb_ld32(x) (__builtin_clz (x) ^ 31)
143 #define ecb_ld64(x) (__builtin_clzll (x) ^ 63)
144 #define ecb_ctz32(x) __builtin_ctz (x)
145 #define ecb_ctz64(x) __builtin_ctzll (x)
146 #define ecb_popcount32(x) __builtin_popcount (x)
147 /* no popcountll */
148 #else
149 ecb_function_ int ecb_ctz32 (uint32_t x) ecb_const;
150 ecb_function_ int
151 ecb_ctz32 (uint32_t x)
152 {
153 int r = 0;
154
155 x &= ~x + 1; /* this isolates the lowest bit */
156
157 #if ECB_branchless_on_i386
158 r += !!(x & 0xaaaaaaaa) << 0;
159 r += !!(x & 0xcccccccc) << 1;
160 r += !!(x & 0xf0f0f0f0) << 2;
161 r += !!(x & 0xff00ff00) << 3;
162 r += !!(x & 0xffff0000) << 4;
163 #else
164 if (x & 0xaaaaaaaa) r += 1;
165 if (x & 0xcccccccc) r += 2;
166 if (x & 0xf0f0f0f0) r += 4;
167 if (x & 0xff00ff00) r += 8;
168 if (x & 0xffff0000) r += 16;
169 #endif
170
171 return r;
172 }
173
174 ecb_function_ int ecb_ctz64 (uint64_t x) ecb_const;
175 ecb_function_ int
176 ecb_ctz64 (uint64_t x)
177 {
178 int shift = x & 0xffffffffU ? 0 : 32;
179 return ecb_ctz32 (x >> shift) + shift;
180 }
181
182 ecb_function_ int ecb_popcount32 (uint32_t x) ecb_const;
183 ecb_function_ int
184 ecb_popcount32 (uint32_t x)
185 {
186 x -= (x >> 1) & 0x55555555;
187 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
188 x = ((x >> 4) + x) & 0x0f0f0f0f;
189 x *= 0x01010101;
190
191 return x >> 24;
192 }
193
194 /* you have the choice beetween something with a table lookup, */
195 /* something using lots of bit arithmetic and a simple loop */
196 /* we went for the loop */
197 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
198 ecb_function_ int ecb_ld32 (uint32_t x)
199 {
200 int r = 0;
201
202 if (x >> 16) { x >>= 16; r += 16; }
203 if (x >> 8) { x >>= 8; r += 8; }
204 if (x >> 4) { x >>= 4; r += 4; }
205 if (x >> 2) { x >>= 2; r += 2; }
206 if (x >> 1) { r += 1; }
207
208 return r;
209 }
210
211 ecb_function_ int ecb_ld64 (uint64_t x) ecb_const;
212 ecb_function_ int ecb_ld64 (uint64_t x)
213 {
214 int r = 0;
215
216 if (x >> 32) { x >>= 32; r += 32; }
217
218 return r + ecb_ld32 (x);
219 }
220 #endif
221
222 /* popcount64 is only available on 64 bit cpus as gcc builtin */
223 /* so for this version we are lazy */
224 ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const;
225 ecb_function_ int
226 ecb_popcount64 (uint64_t x)
227 {
228 return ecb_popcount32 (x) + ecb_popcount32 (x >> 32);
229 }
230
231 ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) ecb_const;
232 ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) ecb_const;
233 ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) ecb_const;
234 ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) ecb_const;
235 ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
236 ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
237 ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) ecb_const;
238 ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) ecb_const;
239
240 ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) { return (x >> ( 8 - count)) | (x << count); }
241 ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) { return (x << ( 8 - count)) | (x >> count); }
242 ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) { return (x >> (16 - count)) | (x << count); }
243 ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) { return (x << (16 - count)) | (x >> count); }
244 ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) { return (x >> (32 - count)) | (x << count); }
245 ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) { return (x << (32 - count)) | (x >> count); }
246 ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) { return (x >> (64 - count)) | (x << count); }
247 ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) { return (x << (64 - count)) | (x >> count); }
248
249 #if ECB_GCC_VERSION(4,3)
250 #define ecb_bswap16(x) (__builtin_bswap32 (x) >> 16)
251 #define ecb_bswap32(x) __builtin_bswap32 (x)
252 #define ecb_bswap64(x) __builtin_bswap64 (x)
253 #else
254 ecb_function_ uint16_t ecb_bswap16 (uint16_t x) ecb_const;
255 ecb_function_ uint16_t
256 ecb_bswap16 (uint16_t x)
257 {
258 return ecb_rotl16 (x, 8);
259 }
260
261 ecb_function_ uint32_t ecb_bswap32 (uint32_t x) ecb_const;
262 ecb_function_ uint32_t
263 ecb_bswap32 (uint32_t x)
264 {
265 return (((uint32_t)ecb_bswap16 (x)) << 16) | ecb_bswap16 (x >> 16);
266 }
267
268 ecb_function_ uint64_t ecb_bswap64 (uint64_t x) ecb_const;
269 ecb_function_ uint64_t
270 ecb_bswap64 (uint64_t x)
271 {
272 return (((uint64_t)ecb_bswap32 (x)) << 32) | ecb_bswap32 (x >> 32);
273 }
274 #endif
275
276 #if ECB_GCC_VERSION(4,5)
277 #define ecb_unreachable() __builtin_unreachable ()
278 #else
279 /* this seems to work fine, but gcc always emits a warning for it :/ */
280 ecb_function_ void ecb_unreachable (void) ecb_noreturn;
281 ecb_function_ void ecb_unreachable (void) { }
282 #endif
283
284 /* try to tell the compiler that some condition is definitely true */
285 #define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0)
286
287 ecb_function_ unsigned char ecb_byteorder_helper (void) ecb_const;
288 ecb_function_ unsigned char
289 ecb_byteorder_helper (void)
290 {
291 const uint32_t u = 0x11223344;
292 return *(unsigned char *)&u;
293 }
294
295 ecb_function_ ecb_bool ecb_big_endian (void) ecb_const;
296 ecb_function_ ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
297 ecb_function_ ecb_bool ecb_little_endian (void) ecb_const;
298 ecb_function_ ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; }
299
300 #if ECB_GCC_VERSION(3,0) || ECB_C99
301 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
302 #else
303 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
304 #endif
305
306 #if ecb_cplusplus_does_not_suck
307 /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */
308 template<typename T, int N>
309 static inline int ecb_array_length (const T (&arr)[N])
310 {
311 return N;
312 }
313 #else
314 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
315 #endif
316
317 #endif
318