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Revision: 1.108
Committed: Fri Jun 29 01:39:51 2012 UTC (11 years, 11 months ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.107: +6 -6 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 0x00010001
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 /* many compilers define _GNUC_ to some versions but then only implement
69 * what their idiot authors think are the "more important" extensions,
70 * causing enormous grief in return for some better fake benchmark numbers.
71 * or so.
72 * we try to detect these and simply assume they are not gcc - if they have
73 * an issue with that they should have done it right in the first place.
74 */
75 #ifndef ECB_GCC_VERSION
76 #if !defined __GNUC_MINOR__ || defined __INTEL_COMPILER || defined __SUNPRO_C || defined __SUNPRO_CC || defined __llvm__ || defined __clang__
77 #define ECB_GCC_VERSION(major,minor) 0
78 #else
79 #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
80 #endif
81 #endif
82
83 #define ECB_C (__STDC__+0) /* this assumes that __STDC__ is either empty or a number */
84 #define ECB_C99 (__STDC_VERSION__ >= 199901L)
85 #define ECB_C11 (__STDC_VERSION__ >= 201112L)
86 #define ECB_CPP (__cplusplus+0)
87 #define ECB_CPP11 (__cplusplus >= 201103L)
88
89 #if ECB_CPP
90 #define ECB_EXTERN_C extern "C"
91 #define ECB_EXTERN_C_BEG ECB_EXTERN_C {
92 #define ECB_EXTERN_C_END }
93 #else
94 #define ECB_EXTERN_C extern
95 #define ECB_EXTERN_C_BEG
96 #define ECB_EXTERN_C_END
97 #endif
98
99 /*****************************************************************************/
100
101 /* ECB_NO_THREADS - ecb is not used by multiple threads, ever */
102 /* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */
103
104 #if ECB_NO_THREADS
105 #define ECB_NO_SMP 1
106 #endif
107
108 #if ECB_NO_SMP
109 #define ECB_MEMORY_FENCE do { } while (0)
110 #endif
111
112 #ifndef ECB_MEMORY_FENCE
113 #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
114 #if __i386 || __i386__
115 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory")
116 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
117 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
118 #elif __amd64 || __amd64__ || __x86_64 || __x86_64__
119 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory")
120 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
121 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
122 #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__
123 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
124 #elif defined __ARM_ARCH_6__ || defined __ARM_ARCH_6J__ \
125 || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__
126 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory")
127 #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \
128 || defined __ARM_ARCH_7M__ || defined __ARM_ARCH_7R__
129 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory")
130 #elif __sparc || __sparc__
131 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad" : : : "memory")
132 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory")
133 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore")
134 #elif defined __s390__ || defined __s390x__
135 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory")
136 #elif defined __mips__
137 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
138 #elif defined __alpha__
139 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mb" : : : "memory")
140 #elif defined __hppa__
141 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory")
142 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
143 #elif defined __ia64__
144 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mf" : : : "memory")
145 #endif
146 #endif
147 #endif
148
149 #ifndef ECB_MEMORY_FENCE
150 #if ECB_GCC_VERSION(4,7)
151 /* see comment below (stdatomic.h) about the C11 memory model. */
152 #define ECB_MEMORY_FENCE __atomic_thread_fence (__ATOMIC_SEQ_CST)
153 /*#elif defined __clang && __has_feature (cxx_atomic)*/
154 /* see comment below (stdatomic.h) about the C11 memory model. */
155 /*#define ECB_MEMORY_FENCE __c11_atomic_thread_fence (__ATOMIC_SEQ_CST)*/
156 #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__
157 #define ECB_MEMORY_FENCE __sync_synchronize ()
158 #elif _MSC_VER >= 1400 /* VC++ 2005 */
159 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
160 #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
161 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
162 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
163 #elif defined _WIN32
164 #include <WinNT.h>
165 #define ECB_MEMORY_FENCE MemoryBarrier () /* actually just xchg on x86... scary */
166 #elif __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
167 #include <mbarrier.h>
168 #define ECB_MEMORY_FENCE __machine_rw_barrier ()
169 #define ECB_MEMORY_FENCE_ACQUIRE __machine_r_barrier ()
170 #define ECB_MEMORY_FENCE_RELEASE __machine_w_barrier ()
171 #elif __xlC__
172 #define ECB_MEMORY_FENCE __sync ()
173 #endif
174 #endif
175
176 #ifndef ECB_MEMORY_FENCE
177 #if ECB_C11 && !defined __STDC_NO_ATOMICS__
178 /* we assume that these memory fences work on all variables/all memory accesses, */
179 /* not just C11 atomics and atomic accesses */
180 #include <stdatomic.h>
181 /* Unfortunately, neither gcc 4.7 nor clang 3.1 generate any instructions for */
182 /* any fence other than seq_cst, which isn't very efficient for us. */
183 /* Why that is, we don't know - either the C11 memory model is quite useless */
184 /* for most usages, or gcc and clang have a bug */
185 /* I *currently* lean towards the latter, and inefficiently implement */
186 /* all three of ecb's fences as a seq_cst fence */
187 #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_seq_cst)
188 #endif
189 #endif
190
191 #ifndef ECB_MEMORY_FENCE
192 #if !ECB_AVOID_PTHREADS
193 /*
194 * if you get undefined symbol references to pthread_mutex_lock,
195 * or failure to find pthread.h, then you should implement
196 * the ECB_MEMORY_FENCE operations for your cpu/compiler
197 * OR provide pthread.h and link against the posix thread library
198 * of your system.
199 */
200 #include <pthread.h>
201 #define ECB_NEEDS_PTHREADS 1
202 #define ECB_MEMORY_FENCE_NEEDS_PTHREADS 1
203
204 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
205 #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0)
206 #endif
207 #endif
208
209 #if !defined ECB_MEMORY_FENCE_ACQUIRE && defined ECB_MEMORY_FENCE
210 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
211 #endif
212
213 #if !defined ECB_MEMORY_FENCE_RELEASE && defined ECB_MEMORY_FENCE
214 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
215 #endif
216
217 /*****************************************************************************/
218
219 #if __cplusplus
220 #define ecb_inline static inline
221 #elif ECB_GCC_VERSION(2,5)
222 #define ecb_inline static __inline__
223 #elif ECB_C99
224 #define ecb_inline static inline
225 #else
226 #define ecb_inline static
227 #endif
228
229 #if ECB_GCC_VERSION(3,3)
230 #define ecb_restrict __restrict__
231 #elif ECB_C99
232 #define ecb_restrict restrict
233 #else
234 #define ecb_restrict
235 #endif
236
237 typedef int ecb_bool;
238
239 #define ECB_CONCAT_(a, b) a ## b
240 #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
241 #define ECB_STRINGIFY_(a) # a
242 #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
243
244 #define ecb_function_ ecb_inline
245
246 #if ECB_GCC_VERSION(3,1)
247 #define ecb_attribute(attrlist) __attribute__(attrlist)
248 #define ecb_is_constant(expr) __builtin_constant_p (expr)
249 #define ecb_expect(expr,value) __builtin_expect ((expr),(value))
250 #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
251 #else
252 #define ecb_attribute(attrlist)
253 #define ecb_is_constant(expr) 0
254 #define ecb_expect(expr,value) (expr)
255 #define ecb_prefetch(addr,rw,locality)
256 #endif
257
258 /* no emulation for ecb_decltype */
259 #if ECB_GCC_VERSION(4,5)
260 #define ecb_decltype(x) __decltype(x)
261 #elif ECB_GCC_VERSION(3,0)
262 #define ecb_decltype(x) __typeof(x)
263 #endif
264
265 #define ecb_noinline ecb_attribute ((__noinline__))
266 #define ecb_unused ecb_attribute ((__unused__))
267 #define ecb_const ecb_attribute ((__const__))
268 #define ecb_pure ecb_attribute ((__pure__))
269
270 #if ECB_C11
271 #define ecb_noreturn _Noreturn
272 #else
273 #define ecb_noreturn ecb_attribute ((__noreturn__))
274 #endif
275
276 #if ECB_GCC_VERSION(4,3)
277 #define ecb_artificial ecb_attribute ((__artificial__))
278 #define ecb_hot ecb_attribute ((__hot__))
279 #define ecb_cold ecb_attribute ((__cold__))
280 #else
281 #define ecb_artificial
282 #define ecb_hot
283 #define ecb_cold
284 #endif
285
286 /* put around conditional expressions if you are very sure that the */
287 /* expression is mostly true or mostly false. note that these return */
288 /* booleans, not the expression. */
289 #define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
290 #define ecb_expect_true(expr) ecb_expect (!!(expr), 1)
291 /* for compatibility to the rest of the world */
292 #define ecb_likely(expr) ecb_expect_true (expr)
293 #define ecb_unlikely(expr) ecb_expect_false (expr)
294
295 /* count trailing zero bits and count # of one bits */
296 #if ECB_GCC_VERSION(3,4)
297 /* we assume int == 32 bit, long == 32 or 64 bit and long long == 64 bit */
298 #define ecb_ld32(x) (__builtin_clz (x) ^ 31)
299 #define ecb_ld64(x) (__builtin_clzll (x) ^ 63)
300 #define ecb_ctz32(x) __builtin_ctz (x)
301 #define ecb_ctz64(x) __builtin_ctzll (x)
302 #define ecb_popcount32(x) __builtin_popcount (x)
303 /* no popcountll */
304 #else
305 ecb_function_ int ecb_ctz32 (uint32_t x) ecb_const;
306 ecb_function_ int
307 ecb_ctz32 (uint32_t x)
308 {
309 int r = 0;
310
311 x &= ~x + 1; /* this isolates the lowest bit */
312
313 #if ECB_branchless_on_i386
314 r += !!(x & 0xaaaaaaaa) << 0;
315 r += !!(x & 0xcccccccc) << 1;
316 r += !!(x & 0xf0f0f0f0) << 2;
317 r += !!(x & 0xff00ff00) << 3;
318 r += !!(x & 0xffff0000) << 4;
319 #else
320 if (x & 0xaaaaaaaa) r += 1;
321 if (x & 0xcccccccc) r += 2;
322 if (x & 0xf0f0f0f0) r += 4;
323 if (x & 0xff00ff00) r += 8;
324 if (x & 0xffff0000) r += 16;
325 #endif
326
327 return r;
328 }
329
330 ecb_function_ int ecb_ctz64 (uint64_t x) ecb_const;
331 ecb_function_ int
332 ecb_ctz64 (uint64_t x)
333 {
334 int shift = x & 0xffffffffU ? 0 : 32;
335 return ecb_ctz32 (x >> shift) + shift;
336 }
337
338 ecb_function_ int ecb_popcount32 (uint32_t x) ecb_const;
339 ecb_function_ int
340 ecb_popcount32 (uint32_t x)
341 {
342 x -= (x >> 1) & 0x55555555;
343 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
344 x = ((x >> 4) + x) & 0x0f0f0f0f;
345 x *= 0x01010101;
346
347 return x >> 24;
348 }
349
350 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
351 ecb_function_ int ecb_ld32 (uint32_t x)
352 {
353 int r = 0;
354
355 if (x >> 16) { x >>= 16; r += 16; }
356 if (x >> 8) { x >>= 8; r += 8; }
357 if (x >> 4) { x >>= 4; r += 4; }
358 if (x >> 2) { x >>= 2; r += 2; }
359 if (x >> 1) { r += 1; }
360
361 return r;
362 }
363
364 ecb_function_ int ecb_ld64 (uint64_t x) ecb_const;
365 ecb_function_ int ecb_ld64 (uint64_t x)
366 {
367 int r = 0;
368
369 if (x >> 32) { x >>= 32; r += 32; }
370
371 return r + ecb_ld32 (x);
372 }
373 #endif
374
375 ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) ecb_const;
376 ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) { return !(x & (x - 1)); }
377 ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) ecb_const;
378 ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) { return !(x & (x - 1)); }
379
380 ecb_function_ uint8_t ecb_bitrev8 (uint8_t x) ecb_const;
381 ecb_function_ uint8_t ecb_bitrev8 (uint8_t x)
382 {
383 return ( (x * 0x0802U & 0x22110U)
384 | (x * 0x8020U & 0x88440U)) * 0x10101U >> 16;
385 }
386
387 ecb_function_ uint16_t ecb_bitrev16 (uint16_t x) ecb_const;
388 ecb_function_ uint16_t ecb_bitrev16 (uint16_t x)
389 {
390 x = ((x >> 1) & 0x5555) | ((x & 0x5555) << 1);
391 x = ((x >> 2) & 0x3333) | ((x & 0x3333) << 2);
392 x = ((x >> 4) & 0x0f0f) | ((x & 0x0f0f) << 4);
393 x = ( x >> 8 ) | ( x << 8);
394
395 return x;
396 }
397
398 ecb_function_ uint32_t ecb_bitrev32 (uint32_t x) ecb_const;
399 ecb_function_ uint32_t ecb_bitrev32 (uint32_t x)
400 {
401 x = ((x >> 1) & 0x55555555) | ((x & 0x55555555) << 1);
402 x = ((x >> 2) & 0x33333333) | ((x & 0x33333333) << 2);
403 x = ((x >> 4) & 0x0f0f0f0f) | ((x & 0x0f0f0f0f) << 4);
404 x = ((x >> 8) & 0x00ff00ff) | ((x & 0x00ff00ff) << 8);
405 x = ( x >> 16 ) | ( x << 16);
406
407 return x;
408 }
409
410 /* popcount64 is only available on 64 bit cpus as gcc builtin */
411 /* so for this version we are lazy */
412 ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const;
413 ecb_function_ int
414 ecb_popcount64 (uint64_t x)
415 {
416 return ecb_popcount32 (x) + ecb_popcount32 (x >> 32);
417 }
418
419 ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) ecb_const;
420 ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) ecb_const;
421 ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) ecb_const;
422 ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) ecb_const;
423 ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
424 ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
425 ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) ecb_const;
426 ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) ecb_const;
427
428 ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) { return (x >> ( 8 - count)) | (x << count); }
429 ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) { return (x << ( 8 - count)) | (x >> count); }
430 ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) { return (x >> (16 - count)) | (x << count); }
431 ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) { return (x << (16 - count)) | (x >> count); }
432 ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) { return (x >> (32 - count)) | (x << count); }
433 ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) { return (x << (32 - count)) | (x >> count); }
434 ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) { return (x >> (64 - count)) | (x << count); }
435 ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) { return (x << (64 - count)) | (x >> count); }
436
437 #if ECB_GCC_VERSION(4,3)
438 #define ecb_bswap16(x) (__builtin_bswap32 (x) >> 16)
439 #define ecb_bswap32(x) __builtin_bswap32 (x)
440 #define ecb_bswap64(x) __builtin_bswap64 (x)
441 #else
442 ecb_function_ uint16_t ecb_bswap16 (uint16_t x) ecb_const;
443 ecb_function_ uint16_t
444 ecb_bswap16 (uint16_t x)
445 {
446 return ecb_rotl16 (x, 8);
447 }
448
449 ecb_function_ uint32_t ecb_bswap32 (uint32_t x) ecb_const;
450 ecb_function_ uint32_t
451 ecb_bswap32 (uint32_t x)
452 {
453 return (((uint32_t)ecb_bswap16 (x)) << 16) | ecb_bswap16 (x >> 16);
454 }
455
456 ecb_function_ uint64_t ecb_bswap64 (uint64_t x) ecb_const;
457 ecb_function_ uint64_t
458 ecb_bswap64 (uint64_t x)
459 {
460 return (((uint64_t)ecb_bswap32 (x)) << 32) | ecb_bswap32 (x >> 32);
461 }
462 #endif
463
464 #if ECB_GCC_VERSION(4,5)
465 #define ecb_unreachable() __builtin_unreachable ()
466 #else
467 /* this seems to work fine, but gcc always emits a warning for it :/ */
468 ecb_inline void ecb_unreachable (void) ecb_noreturn;
469 ecb_inline void ecb_unreachable (void) { }
470 #endif
471
472 /* try to tell the compiler that some condition is definitely true */
473 #define ecb_assume(cond) if (!(cond)) ecb_unreachable (); else 0
474
475 ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const;
476 ecb_inline unsigned char
477 ecb_byteorder_helper (void)
478 {
479 /* the union code still generates code under pressure in gcc, */
480 /* but less than using pointers, and always seem to */
481 /* successfully return a constant. */
482 /* the reason why we have this horrible preprocessor mess */
483 /* is to avoid it in all cases, at least on common architectures */
484 /* and yes, gcc defines __BYTE_ORDER__, g++ does not */
485 #if __i386 || __i386__ || _M_X86 || __amd64 || __amd64__ || _M_X64
486 return 0x44;
487 #elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
488 return 0x44;
489 #elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
490 retrurn 0x11;
491 #else
492 union
493 {
494 uint32_t i;
495 uint8_t c;
496 } u = { 0x11223344 };
497 return u.c;
498 #endif
499 }
500
501 ecb_inline ecb_bool ecb_big_endian (void) ecb_const;
502 ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
503 ecb_inline ecb_bool ecb_little_endian (void) ecb_const;
504 ecb_inline ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; }
505
506 #if ECB_GCC_VERSION(3,0) || ECB_C99
507 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
508 #else
509 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
510 #endif
511
512 #if __cplusplus
513 template<typename T>
514 static inline T ecb_div_rd (T val, T div)
515 {
516 return val < 0 ? - ((-val + div - 1) / div) : (val ) / div;
517 }
518 template<typename T>
519 static inline T ecb_div_ru (T val, T div)
520 {
521 return val < 0 ? - ((-val ) / div) : (val + div - 1) / div;
522 }
523 #else
524 #define ecb_div_rd(val,div) ((val) < 0 ? - ((-(val) + (div) - 1) / (div)) : ((val) ) / (div))
525 #define ecb_div_ru(val,div) ((val) < 0 ? - ((-(val) ) / (div)) : ((val) + (div) - 1) / (div))
526 #endif
527
528 #if ecb_cplusplus_does_not_suck
529 /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */
530 template<typename T, int N>
531 static inline int ecb_array_length (const T (&arr)[N])
532 {
533 return N;
534 }
535 #else
536 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
537 #endif
538
539 /*******************************************************************************/
540 /* floating point stuff, can be disabled by defining ECB_NO_LIBM */
541
542 /* basically, everything uses "ieee pure-endian" floating point numbers */
543 /* the only noteworthy exception is ancient armle, which uses order 43218765 */
544 #if 0 \
545 || __i386 || __i386__ \
546 || __amd64 || __amd64__ || __x86_64 || __x86_64__ \
547 || __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ \
548 || defined __arm__ && defined __ARM_EABI__ \
549 || defined __s390__ || defined __s390x__ \
550 || defined __mips__ \
551 || defined __alpha__ \
552 || defined __hppa__ \
553 || defined __ia64__ \
554 || defined _M_IX86 || defined _M_AMD64 || defined _M_IA64
555 #define ECB_STDFP 1
556 #include <string.h> /* for memcpy */
557 #else
558 #define ECB_STDFP 0
559 #endif
560
561 #ifndef ECB_NO_LIBM
562
563 /* convert a float to ieee single/binary32 */
564 ecb_function_ uint32_t ecb_float_to_binary32 (float x) ecb_const;
565 ecb_function_ uint32_t
566 ecb_float_to_binary32 (float x)
567 {
568 uint32_t r;
569
570 #if ECB_STDFP
571 memcpy (&r, &x, 4);
572 #else
573 /* slow emulation, works for anything but -0 */
574 ECB_EXTERN_C float frexpf (float v, int *e);
575 uint32_t m;
576 int e;
577
578 if (x == 0e0f ) return 0x00000000U;
579 if (x > +3.40282346638528860e+38f) return 0x7f800000U;
580 if (x < -3.40282346638528860e+38f) return 0xff800000U;
581 if (x != x ) return 0x7fbfffffU;
582
583 m = frexpf (x, &e) * 0x1000000U;
584
585 r = m & 0x80000000U;
586
587 if (r)
588 m = -m;
589
590 if (e <= -126)
591 {
592 m &= 0xffffffU;
593 m >>= (-125 - e);
594 e = -126;
595 }
596
597 r |= (e + 126) << 23;
598 r |= m & 0x7fffffU;
599 #endif
600
601 return r;
602 }
603
604 /* converts an ieee single/binary32 to a float */
605 ecb_function_ float ecb_binary32_to_float (uint32_t x) ecb_const;
606 ecb_function_ float
607 ecb_binary32_to_float (uint32_t x)
608 {
609 float r;
610
611 #if ECB_STDFP
612 memcpy (&r, &x, 4);
613 #else
614 /* emulation, only works for normals and subnormals and +0 */
615 ECB_EXTERN_C float ldexpf (float x, int e);
616
617 int neg = x >> 31;
618 int e = (x >> 23) & 0xffU;
619
620 x &= 0x7fffffU;
621
622 if (e)
623 x |= 0x800000U;
624 else
625 e = 1;
626
627 /* we distrust ldexpf a bit and do the 2**-24 scaling by an extra multiply */
628 r = ldexpf (x * (0.5f / 0x800000U), e - 126);
629
630 r = neg ? -r : r;
631 #endif
632
633 return r;
634 }
635
636 /* convert a double to ieee double/binary64 */
637 ecb_function_ uint64_t ecb_double_to_binary64 (double x) ecb_const;
638 ecb_function_ uint64_t
639 ecb_double_to_binary64 (double x)
640 {
641 uint64_t r;
642
643 #if ECB_STDFP
644 memcpy (&r, &x, 8);
645 #else
646 /* slow emulation, works for anything but -0 */
647 ECB_EXTERN_C double frexp (double v, int *e);
648 uint64_t m;
649 int e;
650
651 if (x == 0e0 ) return 0x0000000000000000U;
652 if (x > +1.79769313486231470e+308) return 0x7ff0000000000000U;
653 if (x < -1.79769313486231470e+308) return 0xfff0000000000000U;
654 if (x != x ) return 0X7ff7ffffffffffffU;
655
656 m = frexp (x, &e) * 0x20000000000000U;
657
658 r = m & 0x8000000000000000;;
659
660 if (r)
661 m = -m;
662
663 if (e <= -1022)
664 {
665 m &= 0x1fffffffffffffU;
666 m >>= (-1021 - e);
667 e = -1022;
668 }
669
670 r |= ((uint64_t)(e + 1022)) << 52;
671 r |= m & 0xfffffffffffffU;
672 #endif
673
674 return r;
675 }
676
677 /* converts an ieee double/binary64 to a double */
678 ecb_function_ double ecb_binary64_to_double (uint64_t x) ecb_const;
679 ecb_function_ double
680 ecb_binary64_to_double (uint64_t x)
681 {
682 double r;
683
684 #if ECB_STDFP
685 memcpy (&r, &x, 8);
686 #else
687 /* emulation, only works for normals and subnormals and +0 */
688 ECB_EXTERN_C double ldexp (double x, int e);
689
690 int neg = x >> 63;
691 int e = (x >> 52) & 0x7ffU;
692
693 x &= 0xfffffffffffffU;
694
695 if (e)
696 x |= 0x10000000000000U;
697 else
698 e = 1;
699
700 /* we distrust ldexp a bit and do the 2**-53 scaling by an extra multiply */
701 r = ldexp (x * (0.5 / 0x10000000000000U), e - 1022);
702
703 r = neg ? -r : r;
704 #endif
705
706 return r;
707 }
708
709 #endif
710
711 #endif
712