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Revision: 1.116
Committed: Thu Jul 4 22:32:11 2013 UTC (10 years, 11 months ago) by root
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Branch: MAIN
Changes since 1.115: +3 -1 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 /* GNU/Linux emulates sync on mips1 architectures, so we force it's 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 #endif
157 #endif
158 #endif
159
160 #ifndef ECB_MEMORY_FENCE
161 #if ECB_GCC_VERSION(4,7)
162 /* see comment below (stdatomic.h) about the C11 memory model. */
163 #define ECB_MEMORY_FENCE __atomic_thread_fence (__ATOMIC_SEQ_CST)
164
165 /* The __has_feature syntax from clang is so misdesigned that we cannot use it
166 * without risking compile time errors with other compilers. We *could*
167 * define our own ecb_clang_has_feature, but I just can't be bothered to work
168 * around this shit time and again.
169 * #elif defined __clang && __has_feature (cxx_atomic)
170 * // see comment below (stdatomic.h) about the C11 memory model.
171 * #define ECB_MEMORY_FENCE __c11_atomic_thread_fence (__ATOMIC_SEQ_CST)
172 */
173
174 #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__
175 #define ECB_MEMORY_FENCE __sync_synchronize ()
176 #elif _MSC_VER >= 1400 /* VC++ 2005 */
177 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
178 #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
179 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
180 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
181 #elif defined _WIN32
182 #include <WinNT.h>
183 #define ECB_MEMORY_FENCE MemoryBarrier () /* actually just xchg on x86... scary */
184 #elif __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
185 #include <mbarrier.h>
186 #define ECB_MEMORY_FENCE __machine_rw_barrier ()
187 #define ECB_MEMORY_FENCE_ACQUIRE __machine_r_barrier ()
188 #define ECB_MEMORY_FENCE_RELEASE __machine_w_barrier ()
189 #elif __xlC__
190 #define ECB_MEMORY_FENCE __sync ()
191 #endif
192 #endif
193
194 #ifndef ECB_MEMORY_FENCE
195 #if ECB_C11 && !defined __STDC_NO_ATOMICS__
196 /* we assume that these memory fences work on all variables/all memory accesses, */
197 /* not just C11 atomics and atomic accesses */
198 #include <stdatomic.h>
199 /* Unfortunately, neither gcc 4.7 nor clang 3.1 generate any instructions for */
200 /* any fence other than seq_cst, which isn't very efficient for us. */
201 /* Why that is, we don't know - either the C11 memory model is quite useless */
202 /* for most usages, or gcc and clang have a bug */
203 /* I *currently* lean towards the latter, and inefficiently implement */
204 /* all three of ecb's fences as a seq_cst fence */
205 #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_seq_cst)
206 #endif
207 #endif
208
209 #ifndef ECB_MEMORY_FENCE
210 #if !ECB_AVOID_PTHREADS
211 /*
212 * if you get undefined symbol references to pthread_mutex_lock,
213 * or failure to find pthread.h, then you should implement
214 * the ECB_MEMORY_FENCE operations for your cpu/compiler
215 * OR provide pthread.h and link against the posix thread library
216 * of your system.
217 */
218 #include <pthread.h>
219 #define ECB_NEEDS_PTHREADS 1
220 #define ECB_MEMORY_FENCE_NEEDS_PTHREADS 1
221
222 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
223 #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0)
224 #endif
225 #endif
226
227 #if !defined ECB_MEMORY_FENCE_ACQUIRE && defined ECB_MEMORY_FENCE
228 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
229 #endif
230
231 #if !defined ECB_MEMORY_FENCE_RELEASE && defined ECB_MEMORY_FENCE
232 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
233 #endif
234
235 /*****************************************************************************/
236
237 #if __cplusplus
238 #define ecb_inline static inline
239 #elif ECB_GCC_VERSION(2,5)
240 #define ecb_inline static __inline__
241 #elif ECB_C99
242 #define ecb_inline static inline
243 #else
244 #define ecb_inline static
245 #endif
246
247 #if ECB_GCC_VERSION(3,3)
248 #define ecb_restrict __restrict__
249 #elif ECB_C99
250 #define ecb_restrict restrict
251 #else
252 #define ecb_restrict
253 #endif
254
255 typedef int ecb_bool;
256
257 #define ECB_CONCAT_(a, b) a ## b
258 #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
259 #define ECB_STRINGIFY_(a) # a
260 #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
261
262 #define ecb_function_ ecb_inline
263
264 #if ECB_GCC_VERSION(3,1)
265 #define ecb_attribute(attrlist) __attribute__(attrlist)
266 #define ecb_is_constant(expr) __builtin_constant_p (expr)
267 #define ecb_expect(expr,value) __builtin_expect ((expr),(value))
268 #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
269 #else
270 #define ecb_attribute(attrlist)
271 #define ecb_is_constant(expr) 0
272 #define ecb_expect(expr,value) (expr)
273 #define ecb_prefetch(addr,rw,locality)
274 #endif
275
276 /* no emulation for ecb_decltype */
277 #if ECB_GCC_VERSION(4,5)
278 #define ecb_decltype(x) __decltype(x)
279 #elif ECB_GCC_VERSION(3,0)
280 #define ecb_decltype(x) __typeof(x)
281 #endif
282
283 #define ecb_noinline ecb_attribute ((__noinline__))
284 #define ecb_unused ecb_attribute ((__unused__))
285 #define ecb_const ecb_attribute ((__const__))
286 #define ecb_pure ecb_attribute ((__pure__))
287
288 #if ECB_C11
289 #define ecb_noreturn _Noreturn
290 #else
291 #define ecb_noreturn ecb_attribute ((__noreturn__))
292 #endif
293
294 #if ECB_GCC_VERSION(4,3)
295 #define ecb_artificial ecb_attribute ((__artificial__))
296 #define ecb_hot ecb_attribute ((__hot__))
297 #define ecb_cold ecb_attribute ((__cold__))
298 #else
299 #define ecb_artificial
300 #define ecb_hot
301 #define ecb_cold
302 #endif
303
304 /* put around conditional expressions if you are very sure that the */
305 /* expression is mostly true or mostly false. note that these return */
306 /* booleans, not the expression. */
307 #define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
308 #define ecb_expect_true(expr) ecb_expect (!!(expr), 1)
309 /* for compatibility to the rest of the world */
310 #define ecb_likely(expr) ecb_expect_true (expr)
311 #define ecb_unlikely(expr) ecb_expect_false (expr)
312
313 /* count trailing zero bits and count # of one bits */
314 #if ECB_GCC_VERSION(3,4)
315 /* we assume int == 32 bit, long == 32 or 64 bit and long long == 64 bit */
316 #define ecb_ld32(x) (__builtin_clz (x) ^ 31)
317 #define ecb_ld64(x) (__builtin_clzll (x) ^ 63)
318 #define ecb_ctz32(x) __builtin_ctz (x)
319 #define ecb_ctz64(x) __builtin_ctzll (x)
320 #define ecb_popcount32(x) __builtin_popcount (x)
321 /* no popcountll */
322 #else
323 ecb_function_ int ecb_ctz32 (uint32_t x) ecb_const;
324 ecb_function_ int
325 ecb_ctz32 (uint32_t x)
326 {
327 int r = 0;
328
329 x &= ~x + 1; /* this isolates the lowest bit */
330
331 #if ECB_branchless_on_i386
332 r += !!(x & 0xaaaaaaaa) << 0;
333 r += !!(x & 0xcccccccc) << 1;
334 r += !!(x & 0xf0f0f0f0) << 2;
335 r += !!(x & 0xff00ff00) << 3;
336 r += !!(x & 0xffff0000) << 4;
337 #else
338 if (x & 0xaaaaaaaa) r += 1;
339 if (x & 0xcccccccc) r += 2;
340 if (x & 0xf0f0f0f0) r += 4;
341 if (x & 0xff00ff00) r += 8;
342 if (x & 0xffff0000) r += 16;
343 #endif
344
345 return r;
346 }
347
348 ecb_function_ int ecb_ctz64 (uint64_t x) ecb_const;
349 ecb_function_ int
350 ecb_ctz64 (uint64_t x)
351 {
352 int shift = x & 0xffffffffU ? 0 : 32;
353 return ecb_ctz32 (x >> shift) + shift;
354 }
355
356 ecb_function_ int ecb_popcount32 (uint32_t x) ecb_const;
357 ecb_function_ int
358 ecb_popcount32 (uint32_t x)
359 {
360 x -= (x >> 1) & 0x55555555;
361 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
362 x = ((x >> 4) + x) & 0x0f0f0f0f;
363 x *= 0x01010101;
364
365 return x >> 24;
366 }
367
368 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
369 ecb_function_ int ecb_ld32 (uint32_t x)
370 {
371 int r = 0;
372
373 if (x >> 16) { x >>= 16; r += 16; }
374 if (x >> 8) { x >>= 8; r += 8; }
375 if (x >> 4) { x >>= 4; r += 4; }
376 if (x >> 2) { x >>= 2; r += 2; }
377 if (x >> 1) { r += 1; }
378
379 return r;
380 }
381
382 ecb_function_ int ecb_ld64 (uint64_t x) ecb_const;
383 ecb_function_ int ecb_ld64 (uint64_t x)
384 {
385 int r = 0;
386
387 if (x >> 32) { x >>= 32; r += 32; }
388
389 return r + ecb_ld32 (x);
390 }
391 #endif
392
393 ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) ecb_const;
394 ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) { return !(x & (x - 1)); }
395 ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) ecb_const;
396 ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) { return !(x & (x - 1)); }
397
398 ecb_function_ uint8_t ecb_bitrev8 (uint8_t x) ecb_const;
399 ecb_function_ uint8_t ecb_bitrev8 (uint8_t x)
400 {
401 return ( (x * 0x0802U & 0x22110U)
402 | (x * 0x8020U & 0x88440U)) * 0x10101U >> 16;
403 }
404
405 ecb_function_ uint16_t ecb_bitrev16 (uint16_t x) ecb_const;
406 ecb_function_ uint16_t ecb_bitrev16 (uint16_t x)
407 {
408 x = ((x >> 1) & 0x5555) | ((x & 0x5555) << 1);
409 x = ((x >> 2) & 0x3333) | ((x & 0x3333) << 2);
410 x = ((x >> 4) & 0x0f0f) | ((x & 0x0f0f) << 4);
411 x = ( x >> 8 ) | ( x << 8);
412
413 return x;
414 }
415
416 ecb_function_ uint32_t ecb_bitrev32 (uint32_t x) ecb_const;
417 ecb_function_ uint32_t ecb_bitrev32 (uint32_t x)
418 {
419 x = ((x >> 1) & 0x55555555) | ((x & 0x55555555) << 1);
420 x = ((x >> 2) & 0x33333333) | ((x & 0x33333333) << 2);
421 x = ((x >> 4) & 0x0f0f0f0f) | ((x & 0x0f0f0f0f) << 4);
422 x = ((x >> 8) & 0x00ff00ff) | ((x & 0x00ff00ff) << 8);
423 x = ( x >> 16 ) | ( x << 16);
424
425 return x;
426 }
427
428 /* popcount64 is only available on 64 bit cpus as gcc builtin */
429 /* so for this version we are lazy */
430 ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const;
431 ecb_function_ int
432 ecb_popcount64 (uint64_t x)
433 {
434 return ecb_popcount32 (x) + ecb_popcount32 (x >> 32);
435 }
436
437 ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) ecb_const;
438 ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) ecb_const;
439 ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) ecb_const;
440 ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) ecb_const;
441 ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
442 ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
443 ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) ecb_const;
444 ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) ecb_const;
445
446 ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) { return (x >> ( 8 - count)) | (x << count); }
447 ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) { return (x << ( 8 - count)) | (x >> count); }
448 ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) { return (x >> (16 - count)) | (x << count); }
449 ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) { return (x << (16 - count)) | (x >> count); }
450 ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) { return (x >> (32 - count)) | (x << count); }
451 ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) { return (x << (32 - count)) | (x >> count); }
452 ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) { return (x >> (64 - count)) | (x << count); }
453 ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) { return (x << (64 - count)) | (x >> count); }
454
455 #if ECB_GCC_VERSION(4,3)
456 #define ecb_bswap16(x) (__builtin_bswap32 (x) >> 16)
457 #define ecb_bswap32(x) __builtin_bswap32 (x)
458 #define ecb_bswap64(x) __builtin_bswap64 (x)
459 #else
460 ecb_function_ uint16_t ecb_bswap16 (uint16_t x) ecb_const;
461 ecb_function_ uint16_t
462 ecb_bswap16 (uint16_t x)
463 {
464 return ecb_rotl16 (x, 8);
465 }
466
467 ecb_function_ uint32_t ecb_bswap32 (uint32_t x) ecb_const;
468 ecb_function_ uint32_t
469 ecb_bswap32 (uint32_t x)
470 {
471 return (((uint32_t)ecb_bswap16 (x)) << 16) | ecb_bswap16 (x >> 16);
472 }
473
474 ecb_function_ uint64_t ecb_bswap64 (uint64_t x) ecb_const;
475 ecb_function_ uint64_t
476 ecb_bswap64 (uint64_t x)
477 {
478 return (((uint64_t)ecb_bswap32 (x)) << 32) | ecb_bswap32 (x >> 32);
479 }
480 #endif
481
482 #if ECB_GCC_VERSION(4,5)
483 #define ecb_unreachable() __builtin_unreachable ()
484 #else
485 /* this seems to work fine, but gcc always emits a warning for it :/ */
486 ecb_inline void ecb_unreachable (void) ecb_noreturn;
487 ecb_inline void ecb_unreachable (void) { }
488 #endif
489
490 /* try to tell the compiler that some condition is definitely true */
491 #define ecb_assume(cond) if (!(cond)) ecb_unreachable (); else 0
492
493 ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const;
494 ecb_inline unsigned char
495 ecb_byteorder_helper (void)
496 {
497 /* the union code still generates code under pressure in gcc, */
498 /* but less than using pointers, and always seems to */
499 /* successfully return a constant. */
500 /* the reason why we have this horrible preprocessor mess */
501 /* is to avoid it in all cases, at least on common architectures */
502 /* or when using a recent enough gcc version (>= 4.6) */
503 #if __i386 || __i386__ || _M_X86 || __amd64 || __amd64__ || _M_X64
504 return 0x44;
505 #elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
506 return 0x44;
507 #elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
508 return 0x11;
509 #else
510 union
511 {
512 uint32_t i;
513 uint8_t c;
514 } u = { 0x11223344 };
515 return u.c;
516 #endif
517 }
518
519 ecb_inline ecb_bool ecb_big_endian (void) ecb_const;
520 ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
521 ecb_inline ecb_bool ecb_little_endian (void) ecb_const;
522 ecb_inline ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; }
523
524 #if ECB_GCC_VERSION(3,0) || ECB_C99
525 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
526 #else
527 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
528 #endif
529
530 #if __cplusplus
531 template<typename T>
532 static inline T ecb_div_rd (T val, T div)
533 {
534 return val < 0 ? - ((-val + div - 1) / div) : (val ) / div;
535 }
536 template<typename T>
537 static inline T ecb_div_ru (T val, T div)
538 {
539 return val < 0 ? - ((-val ) / div) : (val + div - 1) / div;
540 }
541 #else
542 #define ecb_div_rd(val,div) ((val) < 0 ? - ((-(val) + (div) - 1) / (div)) : ((val) ) / (div))
543 #define ecb_div_ru(val,div) ((val) < 0 ? - ((-(val) ) / (div)) : ((val) + (div) - 1) / (div))
544 #endif
545
546 #if ecb_cplusplus_does_not_suck
547 /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */
548 template<typename T, int N>
549 static inline int ecb_array_length (const T (&arr)[N])
550 {
551 return N;
552 }
553 #else
554 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
555 #endif
556
557 /*******************************************************************************/
558 /* floating point stuff, can be disabled by defining ECB_NO_LIBM */
559
560 /* basically, everything uses "ieee pure-endian" floating point numbers */
561 /* the only noteworthy exception is ancient armle, which uses order 43218765 */
562 #if 0 \
563 || __i386 || __i386__ \
564 || __amd64 || __amd64__ || __x86_64 || __x86_64__ \
565 || __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ \
566 || defined __arm__ && defined __ARM_EABI__ \
567 || defined __s390__ || defined __s390x__ \
568 || defined __mips__ \
569 || defined __alpha__ \
570 || defined __hppa__ \
571 || defined __ia64__ \
572 || defined _M_IX86 || defined _M_AMD64 || defined _M_IA64
573 #define ECB_STDFP 1
574 #include <string.h> /* for memcpy */
575 #else
576 #define ECB_STDFP 0
577 #include <math.h> /* for frexp*, ldexp* */
578 #endif
579
580 #ifndef ECB_NO_LIBM
581
582 /* convert a float to ieee single/binary32 */
583 ecb_function_ uint32_t ecb_float_to_binary32 (float x) ecb_const;
584 ecb_function_ uint32_t
585 ecb_float_to_binary32 (float x)
586 {
587 uint32_t r;
588
589 #if ECB_STDFP
590 memcpy (&r, &x, 4);
591 #else
592 /* slow emulation, works for anything but -0 */
593 uint32_t m;
594 int e;
595
596 if (x == 0e0f ) return 0x00000000U;
597 if (x > +3.40282346638528860e+38f) return 0x7f800000U;
598 if (x < -3.40282346638528860e+38f) return 0xff800000U;
599 if (x != x ) return 0x7fbfffffU;
600
601 m = frexpf (x, &e) * 0x1000000U;
602
603 r = m & 0x80000000U;
604
605 if (r)
606 m = -m;
607
608 if (e <= -126)
609 {
610 m &= 0xffffffU;
611 m >>= (-125 - e);
612 e = -126;
613 }
614
615 r |= (e + 126) << 23;
616 r |= m & 0x7fffffU;
617 #endif
618
619 return r;
620 }
621
622 /* converts an ieee single/binary32 to a float */
623 ecb_function_ float ecb_binary32_to_float (uint32_t x) ecb_const;
624 ecb_function_ float
625 ecb_binary32_to_float (uint32_t x)
626 {
627 float r;
628
629 #if ECB_STDFP
630 memcpy (&r, &x, 4);
631 #else
632 /* emulation, only works for normals and subnormals and +0 */
633 int neg = x >> 31;
634 int e = (x >> 23) & 0xffU;
635
636 x &= 0x7fffffU;
637
638 if (e)
639 x |= 0x800000U;
640 else
641 e = 1;
642
643 /* we distrust ldexpf a bit and do the 2**-24 scaling by an extra multiply */
644 r = ldexpf (x * (0.5f / 0x800000U), e - 126);
645
646 r = neg ? -r : r;
647 #endif
648
649 return r;
650 }
651
652 /* convert a double to ieee double/binary64 */
653 ecb_function_ uint64_t ecb_double_to_binary64 (double x) ecb_const;
654 ecb_function_ uint64_t
655 ecb_double_to_binary64 (double x)
656 {
657 uint64_t r;
658
659 #if ECB_STDFP
660 memcpy (&r, &x, 8);
661 #else
662 /* slow emulation, works for anything but -0 */
663 uint64_t m;
664 int e;
665
666 if (x == 0e0 ) return 0x0000000000000000U;
667 if (x > +1.79769313486231470e+308) return 0x7ff0000000000000U;
668 if (x < -1.79769313486231470e+308) return 0xfff0000000000000U;
669 if (x != x ) return 0X7ff7ffffffffffffU;
670
671 m = frexp (x, &e) * 0x20000000000000U;
672
673 r = m & 0x8000000000000000;;
674
675 if (r)
676 m = -m;
677
678 if (e <= -1022)
679 {
680 m &= 0x1fffffffffffffU;
681 m >>= (-1021 - e);
682 e = -1022;
683 }
684
685 r |= ((uint64_t)(e + 1022)) << 52;
686 r |= m & 0xfffffffffffffU;
687 #endif
688
689 return r;
690 }
691
692 /* converts an ieee double/binary64 to a double */
693 ecb_function_ double ecb_binary64_to_double (uint64_t x) ecb_const;
694 ecb_function_ double
695 ecb_binary64_to_double (uint64_t x)
696 {
697 double r;
698
699 #if ECB_STDFP
700 memcpy (&r, &x, 8);
701 #else
702 /* emulation, only works for normals and subnormals and +0 */
703 int neg = x >> 63;
704 int e = (x >> 52) & 0x7ffU;
705
706 x &= 0xfffffffffffffU;
707
708 if (e)
709 x |= 0x10000000000000U;
710 else
711 e = 1;
712
713 /* we distrust ldexp a bit and do the 2**-53 scaling by an extra multiply */
714 r = ldexp (x * (0.5 / 0x10000000000000U), e - 1022);
715
716 r = neg ? -r : r;
717 #endif
718
719 return r;
720 }
721
722 #endif
723
724 #endif
725