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Revision: 1.124
Committed: Tue Dec 3 15:35:14 2013 UTC (10 years, 6 months ago) by root
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Branch: MAIN
Changes since 1.123: +1 -1 lines
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# Content
1 /*
2 * libecb - http://software.schmorp.de/pkg/libecb
3 *
4 * Copyright (©) 2009-2013 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 /* 16 bits major, 16 bits minor */
34 #define ECB_VERSION 0x00010003
35
36 #ifdef _WIN32
37 typedef signed char int8_t;
38 typedef unsigned char uint8_t;
39 typedef signed short int16_t;
40 typedef unsigned short uint16_t;
41 typedef signed int int32_t;
42 typedef unsigned int uint32_t;
43 #if __GNUC__
44 typedef signed long long int64_t;
45 typedef unsigned long long uint64_t;
46 #else /* _MSC_VER || __BORLANDC__ */
47 typedef signed __int64 int64_t;
48 typedef unsigned __int64 uint64_t;
49 #endif
50 #ifdef _WIN64
51 #define ECB_PTRSIZE 8
52 typedef uint64_t uintptr_t;
53 typedef int64_t intptr_t;
54 #else
55 #define ECB_PTRSIZE 4
56 typedef uint32_t uintptr_t;
57 typedef int32_t intptr_t;
58 #endif
59 #else
60 #include <inttypes.h>
61 #if UINTMAX_MAX > 0xffffffffU
62 #define ECB_PTRSIZE 8
63 #else
64 #define ECB_PTRSIZE 4
65 #endif
66 #endif
67
68 /* work around x32 idiocy by defining proper macros */
69 #if __x86_64 || _M_AMD64
70 #if _ILP32
71 #define ECB_AMD64_X32 1
72 #else
73 #define ECB_AMD64 1
74 #endif
75 #endif
76
77 /* many compilers define _GNUC_ to some versions but then only implement
78 * what their idiot authors think are the "more important" extensions,
79 * causing enormous grief in return for some better fake benchmark numbers.
80 * or so.
81 * we try to detect these and simply assume they are not gcc - if they have
82 * an issue with that they should have done it right in the first place.
83 */
84 #ifndef ECB_GCC_VERSION
85 #if !defined __GNUC_MINOR__ || defined __INTEL_COMPILER || defined __SUNPRO_C || defined __SUNPRO_CC || defined __llvm__ || defined __clang__
86 #define ECB_GCC_VERSION(major,minor) 0
87 #else
88 #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
89 #endif
90 #endif
91
92 #define ECB_C (__STDC__+0) /* this assumes that __STDC__ is either empty or a number */
93 #define ECB_C99 (__STDC_VERSION__ >= 199901L)
94 #define ECB_C11 (__STDC_VERSION__ >= 201112L)
95 #define ECB_CPP (__cplusplus+0)
96 #define ECB_CPP11 (__cplusplus >= 201103L)
97
98 #if ECB_CPP
99 #define ECB_EXTERN_C extern "C"
100 #define ECB_EXTERN_C_BEG ECB_EXTERN_C {
101 #define ECB_EXTERN_C_END }
102 #else
103 #define ECB_EXTERN_C extern
104 #define ECB_EXTERN_C_BEG
105 #define ECB_EXTERN_C_END
106 #endif
107
108 /*****************************************************************************/
109
110 /* ECB_NO_THREADS - ecb is not used by multiple threads, ever */
111 /* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */
112
113 #if ECB_NO_THREADS
114 #define ECB_NO_SMP 1
115 #endif
116
117 #if ECB_NO_SMP
118 #define ECB_MEMORY_FENCE do { } while (0)
119 #endif
120
121 #ifndef ECB_MEMORY_FENCE
122 #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
123 #if __i386 || __i386__
124 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory")
125 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
126 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
127 #elif __amd64 || __amd64__ || __x86_64 || __x86_64__
128 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory")
129 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
130 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
131 #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__
132 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
133 #elif defined __ARM_ARCH_6__ || defined __ARM_ARCH_6J__ \
134 || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__
135 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory")
136 #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \
137 || defined __ARM_ARCH_7M__ || defined __ARM_ARCH_7R__
138 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory")
139 #elif (__sparc || __sparc__) && !__sparcv8
140 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad" : : : "memory")
141 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory")
142 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore")
143 #elif defined __s390__ || defined __s390x__
144 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory")
145 #elif defined __mips__
146 /* GNU/Linux emulates sync on mips1 architectures, so we force its use */
147 /* anybody else who still uses mips1 is supposed to send in their version, with detection code. */
148 #define ECB_MEMORY_FENCE __asm__ __volatile__ (".set mips2; sync; .set mips0" : : : "memory")
149 #elif defined __alpha__
150 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mb" : : : "memory")
151 #elif defined __hppa__
152 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory")
153 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
154 #elif defined __ia64__
155 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mf" : : : "memory")
156 #elif defined __m68k__
157 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory")
158 #elif defined __m88k__
159 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("tb1 0,%%r0,128" : : : "memory")
160 #elif defined __sh__
161 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory")
162 #endif
163 #endif
164 #endif
165
166 #ifndef ECB_MEMORY_FENCE
167 #if ECB_GCC_VERSION(4,7)
168 /* see comment below (stdatomic.h) about the C11 memory model. */
169 #define ECB_MEMORY_FENCE __atomic_thread_fence (__ATOMIC_SEQ_CST)
170
171 /* The __has_feature syntax from clang is so misdesigned that we cannot use it
172 * without risking compile time errors with other compilers. We *could*
173 * define our own ecb_clang_has_feature, but I just can't be bothered to work
174 * around this shit time and again.
175 * #elif defined __clang && __has_feature (cxx_atomic)
176 * // see comment below (stdatomic.h) about the C11 memory model.
177 * #define ECB_MEMORY_FENCE __c11_atomic_thread_fence (__ATOMIC_SEQ_CST)
178 */
179
180 #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__
181 #define ECB_MEMORY_FENCE __sync_synchronize ()
182 #elif _MSC_VER >= 1400 /* VC++ 2005 */
183 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
184 #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
185 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
186 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
187 #elif defined _WIN32
188 #include <WinNT.h>
189 #define ECB_MEMORY_FENCE MemoryBarrier () /* actually just xchg on x86... scary */
190 #elif __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
191 #include <mbarrier.h>
192 #define ECB_MEMORY_FENCE __machine_rw_barrier ()
193 #define ECB_MEMORY_FENCE_ACQUIRE __machine_r_barrier ()
194 #define ECB_MEMORY_FENCE_RELEASE __machine_w_barrier ()
195 #elif __xlC__
196 #define ECB_MEMORY_FENCE __sync ()
197 #endif
198 #endif
199
200 #ifndef ECB_MEMORY_FENCE
201 #if ECB_C11 && !defined __STDC_NO_ATOMICS__
202 /* we assume that these memory fences work on all variables/all memory accesses, */
203 /* not just C11 atomics and atomic accesses */
204 #include <stdatomic.h>
205 /* Unfortunately, neither gcc 4.7 nor clang 3.1 generate any instructions for */
206 /* any fence other than seq_cst, which isn't very efficient for us. */
207 /* Why that is, we don't know - either the C11 memory model is quite useless */
208 /* for most usages, or gcc and clang have a bug */
209 /* I *currently* lean towards the latter, and inefficiently implement */
210 /* all three of ecb's fences as a seq_cst fence */
211 #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_seq_cst)
212 #endif
213 #endif
214
215 #ifndef ECB_MEMORY_FENCE
216 #if !ECB_AVOID_PTHREADS
217 /*
218 * if you get undefined symbol references to pthread_mutex_lock,
219 * or failure to find pthread.h, then you should implement
220 * the ECB_MEMORY_FENCE operations for your cpu/compiler
221 * OR provide pthread.h and link against the posix thread library
222 * of your system.
223 */
224 #include <pthread.h>
225 #define ECB_NEEDS_PTHREADS 1
226 #define ECB_MEMORY_FENCE_NEEDS_PTHREADS 1
227
228 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
229 #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0)
230 #endif
231 #endif
232
233 #if !defined ECB_MEMORY_FENCE_ACQUIRE && defined ECB_MEMORY_FENCE
234 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
235 #endif
236
237 #if !defined ECB_MEMORY_FENCE_RELEASE && defined ECB_MEMORY_FENCE
238 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
239 #endif
240
241 /*****************************************************************************/
242
243 #if __cplusplus
244 #define ecb_inline static inline
245 #elif ECB_GCC_VERSION(2,5)
246 #define ecb_inline static __inline__
247 #elif ECB_C99
248 #define ecb_inline static inline
249 #else
250 #define ecb_inline static
251 #endif
252
253 #if ECB_GCC_VERSION(3,3)
254 #define ecb_restrict __restrict__
255 #elif ECB_C99
256 #define ecb_restrict restrict
257 #else
258 #define ecb_restrict
259 #endif
260
261 typedef int ecb_bool;
262
263 #define ECB_CONCAT_(a, b) a ## b
264 #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
265 #define ECB_STRINGIFY_(a) # a
266 #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
267
268 #define ecb_function_ ecb_inline
269
270 #if ECB_GCC_VERSION(3,1)
271 #define ecb_attribute(attrlist) __attribute__(attrlist)
272 #define ecb_is_constant(expr) __builtin_constant_p (expr)
273 #define ecb_expect(expr,value) __builtin_expect ((expr),(value))
274 #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
275 #else
276 #define ecb_attribute(attrlist)
277 #define ecb_is_constant(expr) 0
278 #define ecb_expect(expr,value) (expr)
279 #define ecb_prefetch(addr,rw,locality)
280 #endif
281
282 /* no emulation for ecb_decltype */
283 #if ECB_GCC_VERSION(4,5)
284 #define ecb_decltype(x) __decltype(x)
285 #elif ECB_GCC_VERSION(3,0)
286 #define ecb_decltype(x) __typeof(x)
287 #endif
288
289 #define ecb_noinline ecb_attribute ((__noinline__))
290 #define ecb_unused ecb_attribute ((__unused__))
291 #define ecb_const ecb_attribute ((__const__))
292 #define ecb_pure ecb_attribute ((__pure__))
293
294 #if ECB_C11
295 #define ecb_noreturn _Noreturn
296 #else
297 #define ecb_noreturn ecb_attribute ((__noreturn__))
298 #endif
299
300 #if ECB_GCC_VERSION(4,3)
301 #define ecb_artificial ecb_attribute ((__artificial__))
302 #define ecb_hot ecb_attribute ((__hot__))
303 #define ecb_cold ecb_attribute ((__cold__))
304 #else
305 #define ecb_artificial
306 #define ecb_hot
307 #define ecb_cold
308 #endif
309
310 /* put around conditional expressions if you are very sure that the */
311 /* expression is mostly true or mostly false. note that these return */
312 /* booleans, not the expression. */
313 #define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
314 #define ecb_expect_true(expr) ecb_expect (!!(expr), 1)
315 /* for compatibility to the rest of the world */
316 #define ecb_likely(expr) ecb_expect_true (expr)
317 #define ecb_unlikely(expr) ecb_expect_false (expr)
318
319 /* count trailing zero bits and count # of one bits */
320 #if ECB_GCC_VERSION(3,4)
321 /* we assume int == 32 bit, long == 32 or 64 bit and long long == 64 bit */
322 #define ecb_ld32(x) (__builtin_clz (x) ^ 31)
323 #define ecb_ld64(x) (__builtin_clzll (x) ^ 63)
324 #define ecb_ctz32(x) __builtin_ctz (x)
325 #define ecb_ctz64(x) __builtin_ctzll (x)
326 #define ecb_popcount32(x) __builtin_popcount (x)
327 /* no popcountll */
328 #else
329 ecb_function_ int ecb_ctz32 (uint32_t x) ecb_const;
330 ecb_function_ int
331 ecb_ctz32 (uint32_t x)
332 {
333 int r = 0;
334
335 x &= ~x + 1; /* this isolates the lowest bit */
336
337 #if ECB_branchless_on_i386
338 r += !!(x & 0xaaaaaaaa) << 0;
339 r += !!(x & 0xcccccccc) << 1;
340 r += !!(x & 0xf0f0f0f0) << 2;
341 r += !!(x & 0xff00ff00) << 3;
342 r += !!(x & 0xffff0000) << 4;
343 #else
344 if (x & 0xaaaaaaaa) r += 1;
345 if (x & 0xcccccccc) r += 2;
346 if (x & 0xf0f0f0f0) r += 4;
347 if (x & 0xff00ff00) r += 8;
348 if (x & 0xffff0000) r += 16;
349 #endif
350
351 return r;
352 }
353
354 ecb_function_ int ecb_ctz64 (uint64_t x) ecb_const;
355 ecb_function_ int
356 ecb_ctz64 (uint64_t x)
357 {
358 int shift = x & 0xffffffffU ? 0 : 32;
359 return ecb_ctz32 (x >> shift) + shift;
360 }
361
362 ecb_function_ int ecb_popcount32 (uint32_t x) ecb_const;
363 ecb_function_ int
364 ecb_popcount32 (uint32_t x)
365 {
366 x -= (x >> 1) & 0x55555555;
367 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
368 x = ((x >> 4) + x) & 0x0f0f0f0f;
369 x *= 0x01010101;
370
371 return x >> 24;
372 }
373
374 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
375 ecb_function_ int ecb_ld32 (uint32_t x)
376 {
377 int r = 0;
378
379 if (x >> 16) { x >>= 16; r += 16; }
380 if (x >> 8) { x >>= 8; r += 8; }
381 if (x >> 4) { x >>= 4; r += 4; }
382 if (x >> 2) { x >>= 2; r += 2; }
383 if (x >> 1) { r += 1; }
384
385 return r;
386 }
387
388 ecb_function_ int ecb_ld64 (uint64_t x) ecb_const;
389 ecb_function_ int ecb_ld64 (uint64_t x)
390 {
391 int r = 0;
392
393 if (x >> 32) { x >>= 32; r += 32; }
394
395 return r + ecb_ld32 (x);
396 }
397 #endif
398
399 ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) ecb_const;
400 ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) { return !(x & (x - 1)); }
401 ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) ecb_const;
402 ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) { return !(x & (x - 1)); }
403
404 ecb_function_ uint8_t ecb_bitrev8 (uint8_t x) ecb_const;
405 ecb_function_ uint8_t ecb_bitrev8 (uint8_t x)
406 {
407 return ( (x * 0x0802U & 0x22110U)
408 | (x * 0x8020U & 0x88440U)) * 0x10101U >> 16;
409 }
410
411 ecb_function_ uint16_t ecb_bitrev16 (uint16_t x) ecb_const;
412 ecb_function_ uint16_t ecb_bitrev16 (uint16_t x)
413 {
414 x = ((x >> 1) & 0x5555) | ((x & 0x5555) << 1);
415 x = ((x >> 2) & 0x3333) | ((x & 0x3333) << 2);
416 x = ((x >> 4) & 0x0f0f) | ((x & 0x0f0f) << 4);
417 x = ( x >> 8 ) | ( x << 8);
418
419 return x;
420 }
421
422 ecb_function_ uint32_t ecb_bitrev32 (uint32_t x) ecb_const;
423 ecb_function_ uint32_t ecb_bitrev32 (uint32_t x)
424 {
425 x = ((x >> 1) & 0x55555555) | ((x & 0x55555555) << 1);
426 x = ((x >> 2) & 0x33333333) | ((x & 0x33333333) << 2);
427 x = ((x >> 4) & 0x0f0f0f0f) | ((x & 0x0f0f0f0f) << 4);
428 x = ((x >> 8) & 0x00ff00ff) | ((x & 0x00ff00ff) << 8);
429 x = ( x >> 16 ) | ( x << 16);
430
431 return x;
432 }
433
434 /* popcount64 is only available on 64 bit cpus as gcc builtin */
435 /* so for this version we are lazy */
436 ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const;
437 ecb_function_ int
438 ecb_popcount64 (uint64_t x)
439 {
440 return ecb_popcount32 (x) + ecb_popcount32 (x >> 32);
441 }
442
443 ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) ecb_const;
444 ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) ecb_const;
445 ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) ecb_const;
446 ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) ecb_const;
447 ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
448 ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
449 ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) ecb_const;
450 ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) ecb_const;
451
452 ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) { return (x >> ( 8 - count)) | (x << count); }
453 ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) { return (x << ( 8 - count)) | (x >> count); }
454 ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) { return (x >> (16 - count)) | (x << count); }
455 ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) { return (x << (16 - count)) | (x >> count); }
456 ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) { return (x >> (32 - count)) | (x << count); }
457 ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) { return (x << (32 - count)) | (x >> count); }
458 ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) { return (x >> (64 - count)) | (x << count); }
459 ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) { return (x << (64 - count)) | (x >> count); }
460
461 #if ECB_GCC_VERSION(4,3)
462 #define ecb_bswap16(x) (__builtin_bswap32 (x) >> 16)
463 #define ecb_bswap32(x) __builtin_bswap32 (x)
464 #define ecb_bswap64(x) __builtin_bswap64 (x)
465 #else
466 ecb_function_ uint16_t ecb_bswap16 (uint16_t x) ecb_const;
467 ecb_function_ uint16_t
468 ecb_bswap16 (uint16_t x)
469 {
470 return ecb_rotl16 (x, 8);
471 }
472
473 ecb_function_ uint32_t ecb_bswap32 (uint32_t x) ecb_const;
474 ecb_function_ uint32_t
475 ecb_bswap32 (uint32_t x)
476 {
477 return (((uint32_t)ecb_bswap16 (x)) << 16) | ecb_bswap16 (x >> 16);
478 }
479
480 ecb_function_ uint64_t ecb_bswap64 (uint64_t x) ecb_const;
481 ecb_function_ uint64_t
482 ecb_bswap64 (uint64_t x)
483 {
484 return (((uint64_t)ecb_bswap32 (x)) << 32) | ecb_bswap32 (x >> 32);
485 }
486 #endif
487
488 #if ECB_GCC_VERSION(4,5)
489 #define ecb_unreachable() __builtin_unreachable ()
490 #else
491 /* this seems to work fine, but gcc always emits a warning for it :/ */
492 ecb_inline void ecb_unreachable (void) ecb_noreturn;
493 ecb_inline void ecb_unreachable (void) { }
494 #endif
495
496 /* try to tell the compiler that some condition is definitely true */
497 #define ecb_assume(cond) if (!(cond)) ecb_unreachable (); else 0
498
499 ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const;
500 ecb_inline unsigned char
501 ecb_byteorder_helper (void)
502 {
503 /* the union code still generates code under pressure in gcc, */
504 /* but less than using pointers, and always seems to */
505 /* successfully return a constant. */
506 /* the reason why we have this horrible preprocessor mess */
507 /* is to avoid it in all cases, at least on common architectures */
508 /* or when using a recent enough gcc version (>= 4.6) */
509 #if __i386 || __i386__ || _M_X86 || __amd64 || __amd64__ || _M_X64
510 return 0x44;
511 #elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
512 return 0x44;
513 #elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
514 return 0x11;
515 #else
516 union
517 {
518 uint32_t i;
519 uint8_t c;
520 } u = { 0x11223344 };
521 return u.c;
522 #endif
523 }
524
525 ecb_inline ecb_bool ecb_big_endian (void) ecb_const;
526 ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
527 ecb_inline ecb_bool ecb_little_endian (void) ecb_const;
528 ecb_inline ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; }
529
530 #if ECB_GCC_VERSION(3,0) || ECB_C99
531 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
532 #else
533 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
534 #endif
535
536 #if __cplusplus
537 template<typename T>
538 static inline T ecb_div_rd (T val, T div)
539 {
540 return val < 0 ? - ((-val + div - 1) / div) : (val ) / div;
541 }
542 template<typename T>
543 static inline T ecb_div_ru (T val, T div)
544 {
545 return val < 0 ? - ((-val ) / div) : (val + div - 1) / div;
546 }
547 #else
548 #define ecb_div_rd(val,div) ((val) < 0 ? - ((-(val) + (div) - 1) / (div)) : ((val) ) / (div))
549 #define ecb_div_ru(val,div) ((val) < 0 ? - ((-(val) ) / (div)) : ((val) + (div) - 1) / (div))
550 #endif
551
552 #if ecb_cplusplus_does_not_suck
553 /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */
554 template<typename T, int N>
555 static inline int ecb_array_length (const T (&arr)[N])
556 {
557 return N;
558 }
559 #else
560 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
561 #endif
562
563 /*******************************************************************************/
564 /* floating point stuff, can be disabled by defining ECB_NO_LIBM */
565
566 /* basically, everything uses "ieee pure-endian" floating point numbers */
567 /* the only noteworthy exception is ancient armle, which uses order 43218765 */
568 #if 0 \
569 || __i386 || __i386__ \
570 || __amd64 || __amd64__ || __x86_64 || __x86_64__ \
571 || __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ \
572 || defined __arm__ && defined __ARM_EABI__ \
573 || defined __s390__ || defined __s390x__ \
574 || defined __mips__ \
575 || defined __alpha__ \
576 || defined __hppa__ \
577 || defined __ia64__ \
578 || defined __m68k__ \
579 || defined __m88k__ \
580 || defined __sh__ \
581 || defined _M_IX86 || defined _M_AMD64 || defined _M_IA64
582 #define ECB_STDFP 1
583 #include <string.h> /* for memcpy */
584 #else
585 #define ECB_STDFP 0
586 #endif
587
588 #ifndef ECB_NO_LIBM
589
590 #include <math.h> /* for frexp*, ldexp*, INFINITY, NAN */
591
592 /* only the oldest of old doesn't have this one. solaris. */
593 #ifdef INFINITY
594 #define ECB_INFINITY INFINITY
595 #else
596 #define ECB_INFINITY HUGE_VAL
597 #endif
598
599 #ifdef NAN
600 #define ECB_NAN NAN
601 #else
602 #define ECB_NAN ECB_INFINITY
603 #endif
604
605 /* converts an ieee half/binary16 to a float */
606 ecb_function_ float ecb_binary16_to_float (uint16_t x) ecb_const;
607 ecb_function_ float
608 ecb_binary16_to_float (uint16_t x)
609 {
610 int e = (x >> 10) & 0x1f;
611 int m = x & 0x3ff;
612 float r;
613
614 if (!e ) r = ldexpf (m , -24);
615 else if (e != 31) r = ldexpf (m + 0x400, e - 25);
616 else if (m ) r = ECB_NAN;
617 else r = ECB_INFINITY;
618
619 return x & 0x8000 ? -r : r;
620 }
621
622 /* convert a float to ieee single/binary32 */
623 ecb_function_ uint32_t ecb_float_to_binary32 (float x) ecb_const;
624 ecb_function_ uint32_t
625 ecb_float_to_binary32 (float x)
626 {
627 uint32_t r;
628
629 #if ECB_STDFP
630 memcpy (&r, &x, 4);
631 #else
632 /* slow emulation, works for anything but -0 */
633 uint32_t m;
634 int e;
635
636 if (x == 0e0f ) return 0x00000000U;
637 if (x > +3.40282346638528860e+38f) return 0x7f800000U;
638 if (x < -3.40282346638528860e+38f) return 0xff800000U;
639 if (x != x ) return 0x7fbfffffU;
640
641 m = frexpf (x, &e) * 0x1000000U;
642
643 r = m & 0x80000000U;
644
645 if (r)
646 m = -m;
647
648 if (e <= -126)
649 {
650 m &= 0xffffffU;
651 m >>= (-125 - e);
652 e = -126;
653 }
654
655 r |= (e + 126) << 23;
656 r |= m & 0x7fffffU;
657 #endif
658
659 return r;
660 }
661
662 /* converts an ieee single/binary32 to a float */
663 ecb_function_ float ecb_binary32_to_float (uint32_t x) ecb_const;
664 ecb_function_ float
665 ecb_binary32_to_float (uint32_t x)
666 {
667 float r;
668
669 #if ECB_STDFP
670 memcpy (&r, &x, 4);
671 #else
672 /* emulation, only works for normals and subnormals and +0 */
673 int neg = x >> 31;
674 int e = (x >> 23) & 0xffU;
675
676 x &= 0x7fffffU;
677
678 if (e)
679 x |= 0x800000U;
680 else
681 e = 1;
682
683 /* we distrust ldexpf a bit and do the 2**-24 scaling by an extra multiply */
684 r = ldexpf (x * (0.5f / 0x800000U), e - 126);
685
686 r = neg ? -r : r;
687 #endif
688
689 return r;
690 }
691
692 /* convert a double to ieee double/binary64 */
693 ecb_function_ uint64_t ecb_double_to_binary64 (double x) ecb_const;
694 ecb_function_ uint64_t
695 ecb_double_to_binary64 (double x)
696 {
697 uint64_t r;
698
699 #if ECB_STDFP
700 memcpy (&r, &x, 8);
701 #else
702 /* slow emulation, works for anything but -0 */
703 uint64_t m;
704 int e;
705
706 if (x == 0e0 ) return 0x0000000000000000U;
707 if (x > +1.79769313486231470e+308) return 0x7ff0000000000000U;
708 if (x < -1.79769313486231470e+308) return 0xfff0000000000000U;
709 if (x != x ) return 0X7ff7ffffffffffffU;
710
711 m = frexp (x, &e) * 0x20000000000000U;
712
713 r = m & 0x8000000000000000;;
714
715 if (r)
716 m = -m;
717
718 if (e <= -1022)
719 {
720 m &= 0x1fffffffffffffU;
721 m >>= (-1021 - e);
722 e = -1022;
723 }
724
725 r |= ((uint64_t)(e + 1022)) << 52;
726 r |= m & 0xfffffffffffffU;
727 #endif
728
729 return r;
730 }
731
732 /* converts an ieee double/binary64 to a double */
733 ecb_function_ double ecb_binary64_to_double (uint64_t x) ecb_const;
734 ecb_function_ double
735 ecb_binary64_to_double (uint64_t x)
736 {
737 double r;
738
739 #if ECB_STDFP
740 memcpy (&r, &x, 8);
741 #else
742 /* emulation, only works for normals and subnormals and +0 */
743 int neg = x >> 63;
744 int e = (x >> 52) & 0x7ffU;
745
746 x &= 0xfffffffffffffU;
747
748 if (e)
749 x |= 0x10000000000000U;
750 else
751 e = 1;
752
753 /* we distrust ldexp a bit and do the 2**-53 scaling by an extra multiply */
754 r = ldexp (x * (0.5 / 0x10000000000000U), e - 1022);
755
756 r = neg ? -r : r;
757 #endif
758
759 return r;
760 }
761
762 #endif
763
764 #endif
765