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Revision: 1.115
Committed: Wed Dec 19 23:51:24 2012 UTC (11 years, 6 months ago) by root
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Branch: MAIN
Changes since 1.114: +2 -2 lines
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# Content
1 /*
2 * libecb - http://software.schmorp.de/pkg/libecb
3 *
4 * Copyright (©) 2009-2012 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__
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 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
147 #elif defined __alpha__
148 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mb" : : : "memory")
149 #elif defined __hppa__
150 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory")
151 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
152 #elif defined __ia64__
153 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mf" : : : "memory")
154 #endif
155 #endif
156 #endif
157
158 #ifndef ECB_MEMORY_FENCE
159 #if ECB_GCC_VERSION(4,7)
160 /* see comment below (stdatomic.h) about the C11 memory model. */
161 #define ECB_MEMORY_FENCE __atomic_thread_fence (__ATOMIC_SEQ_CST)
162
163 /* The __has_feature syntax from clang is so misdesigned that we cannot use it
164 * without risking compile time errors with other compilers. We *could*
165 * define our own ecb_clang_has_feature, but I just can't be bothered to work
166 * around this shit time and again.
167 * #elif defined __clang && __has_feature (cxx_atomic)
168 * // see comment below (stdatomic.h) about the C11 memory model.
169 * #define ECB_MEMORY_FENCE __c11_atomic_thread_fence (__ATOMIC_SEQ_CST)
170 */
171
172 #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__
173 #define ECB_MEMORY_FENCE __sync_synchronize ()
174 #elif _MSC_VER >= 1400 /* VC++ 2005 */
175 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
176 #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
177 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
178 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
179 #elif defined _WIN32
180 #include <WinNT.h>
181 #define ECB_MEMORY_FENCE MemoryBarrier () /* actually just xchg on x86... scary */
182 #elif __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
183 #include <mbarrier.h>
184 #define ECB_MEMORY_FENCE __machine_rw_barrier ()
185 #define ECB_MEMORY_FENCE_ACQUIRE __machine_r_barrier ()
186 #define ECB_MEMORY_FENCE_RELEASE __machine_w_barrier ()
187 #elif __xlC__
188 #define ECB_MEMORY_FENCE __sync ()
189 #endif
190 #endif
191
192 #ifndef ECB_MEMORY_FENCE
193 #if ECB_C11 && !defined __STDC_NO_ATOMICS__
194 /* we assume that these memory fences work on all variables/all memory accesses, */
195 /* not just C11 atomics and atomic accesses */
196 #include <stdatomic.h>
197 /* Unfortunately, neither gcc 4.7 nor clang 3.1 generate any instructions for */
198 /* any fence other than seq_cst, which isn't very efficient for us. */
199 /* Why that is, we don't know - either the C11 memory model is quite useless */
200 /* for most usages, or gcc and clang have a bug */
201 /* I *currently* lean towards the latter, and inefficiently implement */
202 /* all three of ecb's fences as a seq_cst fence */
203 #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_seq_cst)
204 #endif
205 #endif
206
207 #ifndef ECB_MEMORY_FENCE
208 #if !ECB_AVOID_PTHREADS
209 /*
210 * if you get undefined symbol references to pthread_mutex_lock,
211 * or failure to find pthread.h, then you should implement
212 * the ECB_MEMORY_FENCE operations for your cpu/compiler
213 * OR provide pthread.h and link against the posix thread library
214 * of your system.
215 */
216 #include <pthread.h>
217 #define ECB_NEEDS_PTHREADS 1
218 #define ECB_MEMORY_FENCE_NEEDS_PTHREADS 1
219
220 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
221 #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0)
222 #endif
223 #endif
224
225 #if !defined ECB_MEMORY_FENCE_ACQUIRE && defined ECB_MEMORY_FENCE
226 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
227 #endif
228
229 #if !defined ECB_MEMORY_FENCE_RELEASE && defined ECB_MEMORY_FENCE
230 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
231 #endif
232
233 /*****************************************************************************/
234
235 #if __cplusplus
236 #define ecb_inline static inline
237 #elif ECB_GCC_VERSION(2,5)
238 #define ecb_inline static __inline__
239 #elif ECB_C99
240 #define ecb_inline static inline
241 #else
242 #define ecb_inline static
243 #endif
244
245 #if ECB_GCC_VERSION(3,3)
246 #define ecb_restrict __restrict__
247 #elif ECB_C99
248 #define ecb_restrict restrict
249 #else
250 #define ecb_restrict
251 #endif
252
253 typedef int ecb_bool;
254
255 #define ECB_CONCAT_(a, b) a ## b
256 #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
257 #define ECB_STRINGIFY_(a) # a
258 #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
259
260 #define ecb_function_ ecb_inline
261
262 #if ECB_GCC_VERSION(3,1)
263 #define ecb_attribute(attrlist) __attribute__(attrlist)
264 #define ecb_is_constant(expr) __builtin_constant_p (expr)
265 #define ecb_expect(expr,value) __builtin_expect ((expr),(value))
266 #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
267 #else
268 #define ecb_attribute(attrlist)
269 #define ecb_is_constant(expr) 0
270 #define ecb_expect(expr,value) (expr)
271 #define ecb_prefetch(addr,rw,locality)
272 #endif
273
274 /* no emulation for ecb_decltype */
275 #if ECB_GCC_VERSION(4,5)
276 #define ecb_decltype(x) __decltype(x)
277 #elif ECB_GCC_VERSION(3,0)
278 #define ecb_decltype(x) __typeof(x)
279 #endif
280
281 #define ecb_noinline ecb_attribute ((__noinline__))
282 #define ecb_unused ecb_attribute ((__unused__))
283 #define ecb_const ecb_attribute ((__const__))
284 #define ecb_pure ecb_attribute ((__pure__))
285
286 #if ECB_C11
287 #define ecb_noreturn _Noreturn
288 #else
289 #define ecb_noreturn ecb_attribute ((__noreturn__))
290 #endif
291
292 #if ECB_GCC_VERSION(4,3)
293 #define ecb_artificial ecb_attribute ((__artificial__))
294 #define ecb_hot ecb_attribute ((__hot__))
295 #define ecb_cold ecb_attribute ((__cold__))
296 #else
297 #define ecb_artificial
298 #define ecb_hot
299 #define ecb_cold
300 #endif
301
302 /* put around conditional expressions if you are very sure that the */
303 /* expression is mostly true or mostly false. note that these return */
304 /* booleans, not the expression. */
305 #define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
306 #define ecb_expect_true(expr) ecb_expect (!!(expr), 1)
307 /* for compatibility to the rest of the world */
308 #define ecb_likely(expr) ecb_expect_true (expr)
309 #define ecb_unlikely(expr) ecb_expect_false (expr)
310
311 /* count trailing zero bits and count # of one bits */
312 #if ECB_GCC_VERSION(3,4)
313 /* we assume int == 32 bit, long == 32 or 64 bit and long long == 64 bit */
314 #define ecb_ld32(x) (__builtin_clz (x) ^ 31)
315 #define ecb_ld64(x) (__builtin_clzll (x) ^ 63)
316 #define ecb_ctz32(x) __builtin_ctz (x)
317 #define ecb_ctz64(x) __builtin_ctzll (x)
318 #define ecb_popcount32(x) __builtin_popcount (x)
319 /* no popcountll */
320 #else
321 ecb_function_ int ecb_ctz32 (uint32_t x) ecb_const;
322 ecb_function_ int
323 ecb_ctz32 (uint32_t x)
324 {
325 int r = 0;
326
327 x &= ~x + 1; /* this isolates the lowest bit */
328
329 #if ECB_branchless_on_i386
330 r += !!(x & 0xaaaaaaaa) << 0;
331 r += !!(x & 0xcccccccc) << 1;
332 r += !!(x & 0xf0f0f0f0) << 2;
333 r += !!(x & 0xff00ff00) << 3;
334 r += !!(x & 0xffff0000) << 4;
335 #else
336 if (x & 0xaaaaaaaa) r += 1;
337 if (x & 0xcccccccc) r += 2;
338 if (x & 0xf0f0f0f0) r += 4;
339 if (x & 0xff00ff00) r += 8;
340 if (x & 0xffff0000) r += 16;
341 #endif
342
343 return r;
344 }
345
346 ecb_function_ int ecb_ctz64 (uint64_t x) ecb_const;
347 ecb_function_ int
348 ecb_ctz64 (uint64_t x)
349 {
350 int shift = x & 0xffffffffU ? 0 : 32;
351 return ecb_ctz32 (x >> shift) + shift;
352 }
353
354 ecb_function_ int ecb_popcount32 (uint32_t x) ecb_const;
355 ecb_function_ int
356 ecb_popcount32 (uint32_t x)
357 {
358 x -= (x >> 1) & 0x55555555;
359 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
360 x = ((x >> 4) + x) & 0x0f0f0f0f;
361 x *= 0x01010101;
362
363 return x >> 24;
364 }
365
366 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
367 ecb_function_ int ecb_ld32 (uint32_t x)
368 {
369 int r = 0;
370
371 if (x >> 16) { x >>= 16; r += 16; }
372 if (x >> 8) { x >>= 8; r += 8; }
373 if (x >> 4) { x >>= 4; r += 4; }
374 if (x >> 2) { x >>= 2; r += 2; }
375 if (x >> 1) { r += 1; }
376
377 return r;
378 }
379
380 ecb_function_ int ecb_ld64 (uint64_t x) ecb_const;
381 ecb_function_ int ecb_ld64 (uint64_t x)
382 {
383 int r = 0;
384
385 if (x >> 32) { x >>= 32; r += 32; }
386
387 return r + ecb_ld32 (x);
388 }
389 #endif
390
391 ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) ecb_const;
392 ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) { return !(x & (x - 1)); }
393 ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) ecb_const;
394 ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) { return !(x & (x - 1)); }
395
396 ecb_function_ uint8_t ecb_bitrev8 (uint8_t x) ecb_const;
397 ecb_function_ uint8_t ecb_bitrev8 (uint8_t x)
398 {
399 return ( (x * 0x0802U & 0x22110U)
400 | (x * 0x8020U & 0x88440U)) * 0x10101U >> 16;
401 }
402
403 ecb_function_ uint16_t ecb_bitrev16 (uint16_t x) ecb_const;
404 ecb_function_ uint16_t ecb_bitrev16 (uint16_t x)
405 {
406 x = ((x >> 1) & 0x5555) | ((x & 0x5555) << 1);
407 x = ((x >> 2) & 0x3333) | ((x & 0x3333) << 2);
408 x = ((x >> 4) & 0x0f0f) | ((x & 0x0f0f) << 4);
409 x = ( x >> 8 ) | ( x << 8);
410
411 return x;
412 }
413
414 ecb_function_ uint32_t ecb_bitrev32 (uint32_t x) ecb_const;
415 ecb_function_ uint32_t ecb_bitrev32 (uint32_t x)
416 {
417 x = ((x >> 1) & 0x55555555) | ((x & 0x55555555) << 1);
418 x = ((x >> 2) & 0x33333333) | ((x & 0x33333333) << 2);
419 x = ((x >> 4) & 0x0f0f0f0f) | ((x & 0x0f0f0f0f) << 4);
420 x = ((x >> 8) & 0x00ff00ff) | ((x & 0x00ff00ff) << 8);
421 x = ( x >> 16 ) | ( x << 16);
422
423 return x;
424 }
425
426 /* popcount64 is only available on 64 bit cpus as gcc builtin */
427 /* so for this version we are lazy */
428 ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const;
429 ecb_function_ int
430 ecb_popcount64 (uint64_t x)
431 {
432 return ecb_popcount32 (x) + ecb_popcount32 (x >> 32);
433 }
434
435 ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) ecb_const;
436 ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) ecb_const;
437 ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) ecb_const;
438 ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) ecb_const;
439 ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
440 ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
441 ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) ecb_const;
442 ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) ecb_const;
443
444 ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) { return (x >> ( 8 - count)) | (x << count); }
445 ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) { return (x << ( 8 - count)) | (x >> count); }
446 ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) { return (x >> (16 - count)) | (x << count); }
447 ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) { return (x << (16 - count)) | (x >> count); }
448 ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) { return (x >> (32 - count)) | (x << count); }
449 ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) { return (x << (32 - count)) | (x >> count); }
450 ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) { return (x >> (64 - count)) | (x << count); }
451 ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) { return (x << (64 - count)) | (x >> count); }
452
453 #if ECB_GCC_VERSION(4,3)
454 #define ecb_bswap16(x) (__builtin_bswap32 (x) >> 16)
455 #define ecb_bswap32(x) __builtin_bswap32 (x)
456 #define ecb_bswap64(x) __builtin_bswap64 (x)
457 #else
458 ecb_function_ uint16_t ecb_bswap16 (uint16_t x) ecb_const;
459 ecb_function_ uint16_t
460 ecb_bswap16 (uint16_t x)
461 {
462 return ecb_rotl16 (x, 8);
463 }
464
465 ecb_function_ uint32_t ecb_bswap32 (uint32_t x) ecb_const;
466 ecb_function_ uint32_t
467 ecb_bswap32 (uint32_t x)
468 {
469 return (((uint32_t)ecb_bswap16 (x)) << 16) | ecb_bswap16 (x >> 16);
470 }
471
472 ecb_function_ uint64_t ecb_bswap64 (uint64_t x) ecb_const;
473 ecb_function_ uint64_t
474 ecb_bswap64 (uint64_t x)
475 {
476 return (((uint64_t)ecb_bswap32 (x)) << 32) | ecb_bswap32 (x >> 32);
477 }
478 #endif
479
480 #if ECB_GCC_VERSION(4,5)
481 #define ecb_unreachable() __builtin_unreachable ()
482 #else
483 /* this seems to work fine, but gcc always emits a warning for it :/ */
484 ecb_inline void ecb_unreachable (void) ecb_noreturn;
485 ecb_inline void ecb_unreachable (void) { }
486 #endif
487
488 /* try to tell the compiler that some condition is definitely true */
489 #define ecb_assume(cond) if (!(cond)) ecb_unreachable (); else 0
490
491 ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const;
492 ecb_inline unsigned char
493 ecb_byteorder_helper (void)
494 {
495 /* the union code still generates code under pressure in gcc, */
496 /* but less than using pointers, and always seems to */
497 /* successfully return a constant. */
498 /* the reason why we have this horrible preprocessor mess */
499 /* is to avoid it in all cases, at least on common architectures */
500 /* or when using a recent enough gcc version (>= 4.6) */
501 #if __i386 || __i386__ || _M_X86 || __amd64 || __amd64__ || _M_X64
502 return 0x44;
503 #elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
504 return 0x44;
505 #elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
506 return 0x11;
507 #else
508 union
509 {
510 uint32_t i;
511 uint8_t c;
512 } u = { 0x11223344 };
513 return u.c;
514 #endif
515 }
516
517 ecb_inline ecb_bool ecb_big_endian (void) ecb_const;
518 ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
519 ecb_inline ecb_bool ecb_little_endian (void) ecb_const;
520 ecb_inline ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; }
521
522 #if ECB_GCC_VERSION(3,0) || ECB_C99
523 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
524 #else
525 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
526 #endif
527
528 #if __cplusplus
529 template<typename T>
530 static inline T ecb_div_rd (T val, T div)
531 {
532 return val < 0 ? - ((-val + div - 1) / div) : (val ) / div;
533 }
534 template<typename T>
535 static inline T ecb_div_ru (T val, T div)
536 {
537 return val < 0 ? - ((-val ) / div) : (val + div - 1) / div;
538 }
539 #else
540 #define ecb_div_rd(val,div) ((val) < 0 ? - ((-(val) + (div) - 1) / (div)) : ((val) ) / (div))
541 #define ecb_div_ru(val,div) ((val) < 0 ? - ((-(val) ) / (div)) : ((val) + (div) - 1) / (div))
542 #endif
543
544 #if ecb_cplusplus_does_not_suck
545 /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */
546 template<typename T, int N>
547 static inline int ecb_array_length (const T (&arr)[N])
548 {
549 return N;
550 }
551 #else
552 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
553 #endif
554
555 /*******************************************************************************/
556 /* floating point stuff, can be disabled by defining ECB_NO_LIBM */
557
558 /* basically, everything uses "ieee pure-endian" floating point numbers */
559 /* the only noteworthy exception is ancient armle, which uses order 43218765 */
560 #if 0 \
561 || __i386 || __i386__ \
562 || __amd64 || __amd64__ || __x86_64 || __x86_64__ \
563 || __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ \
564 || defined __arm__ && defined __ARM_EABI__ \
565 || defined __s390__ || defined __s390x__ \
566 || defined __mips__ \
567 || defined __alpha__ \
568 || defined __hppa__ \
569 || defined __ia64__ \
570 || defined _M_IX86 || defined _M_AMD64 || defined _M_IA64
571 #define ECB_STDFP 1
572 #include <string.h> /* for memcpy */
573 #else
574 #define ECB_STDFP 0
575 #include <math.h> /* for frexp*, ldexp* */
576 #endif
577
578 #ifndef ECB_NO_LIBM
579
580 /* convert a float to ieee single/binary32 */
581 ecb_function_ uint32_t ecb_float_to_binary32 (float x) ecb_const;
582 ecb_function_ uint32_t
583 ecb_float_to_binary32 (float x)
584 {
585 uint32_t r;
586
587 #if ECB_STDFP
588 memcpy (&r, &x, 4);
589 #else
590 /* slow emulation, works for anything but -0 */
591 uint32_t m;
592 int e;
593
594 if (x == 0e0f ) return 0x00000000U;
595 if (x > +3.40282346638528860e+38f) return 0x7f800000U;
596 if (x < -3.40282346638528860e+38f) return 0xff800000U;
597 if (x != x ) return 0x7fbfffffU;
598
599 m = frexpf (x, &e) * 0x1000000U;
600
601 r = m & 0x80000000U;
602
603 if (r)
604 m = -m;
605
606 if (e <= -126)
607 {
608 m &= 0xffffffU;
609 m >>= (-125 - e);
610 e = -126;
611 }
612
613 r |= (e + 126) << 23;
614 r |= m & 0x7fffffU;
615 #endif
616
617 return r;
618 }
619
620 /* converts an ieee single/binary32 to a float */
621 ecb_function_ float ecb_binary32_to_float (uint32_t x) ecb_const;
622 ecb_function_ float
623 ecb_binary32_to_float (uint32_t x)
624 {
625 float r;
626
627 #if ECB_STDFP
628 memcpy (&r, &x, 4);
629 #else
630 /* emulation, only works for normals and subnormals and +0 */
631 int neg = x >> 31;
632 int e = (x >> 23) & 0xffU;
633
634 x &= 0x7fffffU;
635
636 if (e)
637 x |= 0x800000U;
638 else
639 e = 1;
640
641 /* we distrust ldexpf a bit and do the 2**-24 scaling by an extra multiply */
642 r = ldexpf (x * (0.5f / 0x800000U), e - 126);
643
644 r = neg ? -r : r;
645 #endif
646
647 return r;
648 }
649
650 /* convert a double to ieee double/binary64 */
651 ecb_function_ uint64_t ecb_double_to_binary64 (double x) ecb_const;
652 ecb_function_ uint64_t
653 ecb_double_to_binary64 (double x)
654 {
655 uint64_t r;
656
657 #if ECB_STDFP
658 memcpy (&r, &x, 8);
659 #else
660 /* slow emulation, works for anything but -0 */
661 uint64_t m;
662 int e;
663
664 if (x == 0e0 ) return 0x0000000000000000U;
665 if (x > +1.79769313486231470e+308) return 0x7ff0000000000000U;
666 if (x < -1.79769313486231470e+308) return 0xfff0000000000000U;
667 if (x != x ) return 0X7ff7ffffffffffffU;
668
669 m = frexp (x, &e) * 0x20000000000000U;
670
671 r = m & 0x8000000000000000;;
672
673 if (r)
674 m = -m;
675
676 if (e <= -1022)
677 {
678 m &= 0x1fffffffffffffU;
679 m >>= (-1021 - e);
680 e = -1022;
681 }
682
683 r |= ((uint64_t)(e + 1022)) << 52;
684 r |= m & 0xfffffffffffffU;
685 #endif
686
687 return r;
688 }
689
690 /* converts an ieee double/binary64 to a double */
691 ecb_function_ double ecb_binary64_to_double (uint64_t x) ecb_const;
692 ecb_function_ double
693 ecb_binary64_to_double (uint64_t x)
694 {
695 double r;
696
697 #if ECB_STDFP
698 memcpy (&r, &x, 8);
699 #else
700 /* emulation, only works for normals and subnormals and +0 */
701 int neg = x >> 63;
702 int e = (x >> 52) & 0x7ffU;
703
704 x &= 0xfffffffffffffU;
705
706 if (e)
707 x |= 0x10000000000000U;
708 else
709 e = 1;
710
711 /* we distrust ldexp a bit and do the 2**-53 scaling by an extra multiply */
712 r = ldexp (x * (0.5 / 0x10000000000000U), e - 1022);
713
714 r = neg ? -r : r;
715 #endif
716
717 return r;
718 }
719
720 #endif
721
722 #endif
723