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Comparing libeio/ecb.h (file contents):
Revision 1.6 by root, Tue Jul 26 11:07:08 2011 UTC vs.
Revision 1.18 by root, Sat Sep 7 23:18:23 2013 UTC

1/* 1/*
2 * libecb - http://software.schmorp.de/pkg/libecb 2 * libecb - http://software.schmorp.de/pkg/libecb
3 * 3 *
4 * Copyright (©) 2009-2011 Marc Alexander Lehmann <libecb@schmorp.de> 4 * Copyright (©) 2009-2012 Marc Alexander Lehmann <libecb@schmorp.de>
5 * Copyright (©) 2011 Emanuele Giaquinta 5 * Copyright (©) 2011 Emanuele Giaquinta
6 * All rights reserved. 6 * All rights reserved.
7 * 7 *
8 * Redistribution and use in source and binary forms, with or without modifica- 8 * Redistribution and use in source and binary forms, with or without modifica-
9 * tion, are permitted provided that the following conditions are met: 9 * tion, are permitted provided that the following conditions are met:
… …
28 */ 28 */
29 29
30#ifndef ECB_H 30#ifndef ECB_H
31#define ECB_H 31#define ECB_H
32 32
33/* 16 bits major, 16 bits minor */
34#define ECB_VERSION 0x00010003
35
33#ifdef _WIN32 36#ifdef _WIN32
34 typedef signed char int8_t; 37 typedef signed char int8_t;
35 typedef unsigned char uint8_t; 38 typedef unsigned char uint8_t;
36 typedef signed short int16_t; 39 typedef signed short int16_t;
37 typedef unsigned short uint16_t; 40 typedef unsigned short uint16_t;
… …
42 typedef unsigned long long uint64_t; 45 typedef unsigned long long uint64_t;
43 #else /* _MSC_VER || __BORLANDC__ */ 46 #else /* _MSC_VER || __BORLANDC__ */
44 typedef signed __int64 int64_t; 47 typedef signed __int64 int64_t;
45 typedef unsigned __int64 uint64_t; 48 typedef unsigned __int64 uint64_t;
46 #endif 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
47#else 59#else
48 #include <inttypes.h> 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
49#endif 75#endif
50 76
51/* many compilers define _GNUC_ to some versions but then only implement 77/* many compilers define _GNUC_ to some versions but then only implement
52 * what their idiot authors think are the "more important" extensions, 78 * what their idiot authors think are the "more important" extensions,
53 * causing enourmous grief in return for some better fake benchmark numbers. 79 * causing enormous grief in return for some better fake benchmark numbers.
54 * or so. 80 * or so.
55 * we try to detect these and simply assume they are not gcc - if they have 81 * we try to detect these and simply assume they are not gcc - if they have
56 * an issue with that they should have done it right in the first place. 82 * an issue with that they should have done it right in the first place.
57 */ 83 */
58#ifndef ECB_GCC_VERSION 84#ifndef ECB_GCC_VERSION
59 #if !defined(__GNUC_MINOR__) || defined(__INTEL_COMPILER) || defined(__SUNPRO_C) || defined(__SUNPRO_CC) || defined(__llvm__) || defined(__clang__) 85 #if !defined __GNUC_MINOR__ || defined __INTEL_COMPILER || defined __SUNPRO_C || defined __SUNPRO_CC || defined __llvm__ || defined __clang__
60 #define ECB_GCC_VERSION(major,minor) 0 86 #define ECB_GCC_VERSION(major,minor) 0
61 #else 87 #else
62 #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor))) 88 #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
63 #endif 89 #endif
64#endif 90#endif
65 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
66/*****************************************************************************/ 108/*****************************************************************************/
67 109
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
68#ifndef ECB_MEMORY_FENCE 121#ifndef ECB_MEMORY_FENCE
69 #if ECB_GCC_VERSION(2,5) 122 #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
70 #if __x86 123 #if __i386 || __i386__
71 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory") 124 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory")
72 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE 125 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
73 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE /* better be safe than sorry */ 126 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
74 #elif __amd64 127 #elif __amd64 || __amd64__ || __x86_64 || __x86_64__
75 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory") 128 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory")
76 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("lfence" : : : "memory") 129 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
77 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("sfence") 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")
78 #endif 156 #endif
79 #endif 157 #endif
80#endif 158#endif
81 159
82#ifndef ECB_MEMORY_FENCE 160#ifndef ECB_MEMORY_FENCE
83 #if ECB_GCC_VERSION(4,4) 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__
84 #define ECB_MEMORY_FENCE __sync_synchronize () 175 #define ECB_MEMORY_FENCE __sync_synchronize ()
85 #define ECB_MEMORY_FENCE_ACQUIRE ({ char dummy = 0; __sync_lock_test_and_set (&dummy, 1); }) 176 #elif _MSC_VER >= 1400 /* VC++ 2005 */
86 #define ECB_MEMORY_FENCE_RELEASE ({ char dummy = 1; __sync_lock_release (&dummy ); }) 177 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
87 #elif _MSC_VER >= 1400 && 0 /* TODO: only true when using volatiles */
88 #define ECB_MEMORY_FENCE do { } while (0) 178 #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
89 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE 179 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
90 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE 180 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
91 #elif defined(_WIN32) 181 #elif defined _WIN32
92 #include <WinNT.h> 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>
93 #define ECB_MEMORY_FENCE MemoryBarrier () 186 #define ECB_MEMORY_FENCE __machine_rw_barrier ()
94 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE 187 #define ECB_MEMORY_FENCE_ACQUIRE __machine_r_barrier ()
95 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE 188 #define ECB_MEMORY_FENCE_RELEASE __machine_w_barrier ()
189 #elif __xlC__
190 #define ECB_MEMORY_FENCE __sync ()
96 #endif 191 #endif
97#endif 192#endif
98 193
99#ifndef ECB_MEMORY_FENCE 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 */
100 #include <pthread.h> 218 #include <pthread.h>
219 #define ECB_NEEDS_PTHREADS 1
220 #define ECB_MEMORY_FENCE_NEEDS_PTHREADS 1
101 221
102 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER; 222 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
103 #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0) 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
104 #define ECB_MEMORY_FENCE_ACQUIRE 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
105 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE 232 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
106#endif 233#endif
107 234
108/*****************************************************************************/ 235/*****************************************************************************/
109
110#define ECB_C99 (__STDC_VERSION__ >= 199901L)
111 236
112#if __cplusplus 237#if __cplusplus
113 #define ecb_inline static inline 238 #define ecb_inline static inline
114#elif ECB_GCC_VERSION(2,5) 239#elif ECB_GCC_VERSION(2,5)
115 #define ecb_inline static __inline__ 240 #define ecb_inline static __inline__
… …
154#elif ECB_GCC_VERSION(3,0) 279#elif ECB_GCC_VERSION(3,0)
155 #define ecb_decltype(x) __typeof(x) 280 #define ecb_decltype(x) __typeof(x)
156#endif 281#endif
157 282
158#define ecb_noinline ecb_attribute ((__noinline__)) 283#define ecb_noinline ecb_attribute ((__noinline__))
159#define ecb_noreturn ecb_attribute ((__noreturn__))
160#define ecb_unused ecb_attribute ((__unused__)) 284#define ecb_unused ecb_attribute ((__unused__))
161#define ecb_const ecb_attribute ((__const__)) 285#define ecb_const ecb_attribute ((__const__))
162#define ecb_pure ecb_attribute ((__pure__)) 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
163 293
164#if ECB_GCC_VERSION(4,3) 294#if ECB_GCC_VERSION(4,3)
165 #define ecb_artificial ecb_attribute ((__artificial__)) 295 #define ecb_artificial ecb_attribute ((__artificial__))
166 #define ecb_hot ecb_attribute ((__hot__)) 296 #define ecb_hot ecb_attribute ((__hot__))
167 #define ecb_cold ecb_attribute ((__cold__)) 297 #define ecb_cold ecb_attribute ((__cold__))
… …
233 x *= 0x01010101; 363 x *= 0x01010101;
234 364
235 return x >> 24; 365 return x >> 24;
236 } 366 }
237 367
238 /* you have the choice beetween something with a table lookup, */
239 /* something using lots of bit arithmetic and a simple loop */
240 /* we went for the loop */
241 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const; 368 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
242 ecb_function_ int ecb_ld32 (uint32_t x) 369 ecb_function_ int ecb_ld32 (uint32_t x)
243 { 370 {
244 int r = 0; 371 int r = 0;
245 372
… …
260 if (x >> 32) { x >>= 32; r += 32; } 387 if (x >> 32) { x >>= 32; r += 32; }
261 388
262 return r + ecb_ld32 (x); 389 return r + ecb_ld32 (x);
263 } 390 }
264#endif 391#endif
392
393ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) ecb_const;
394ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) { return !(x & (x - 1)); }
395ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) ecb_const;
396ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) { return !(x & (x - 1)); }
397
398ecb_function_ uint8_t ecb_bitrev8 (uint8_t x) ecb_const;
399ecb_function_ uint8_t ecb_bitrev8 (uint8_t x)
400{
401 return ( (x * 0x0802U & 0x22110U)
402 | (x * 0x8020U & 0x88440U)) * 0x10101U >> 16;
403}
404
405ecb_function_ uint16_t ecb_bitrev16 (uint16_t x) ecb_const;
406ecb_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
416ecb_function_ uint32_t ecb_bitrev32 (uint32_t x) ecb_const;
417ecb_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}
265 427
266/* popcount64 is only available on 64 bit cpus as gcc builtin */ 428/* popcount64 is only available on 64 bit cpus as gcc builtin */
267/* so for this version we are lazy */ 429/* so for this version we are lazy */
268ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const; 430ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const;
269ecb_function_ int 431ecb_function_ int
… …
319 481
320#if ECB_GCC_VERSION(4,5) 482#if ECB_GCC_VERSION(4,5)
321 #define ecb_unreachable() __builtin_unreachable () 483 #define ecb_unreachable() __builtin_unreachable ()
322#else 484#else
323 /* this seems to work fine, but gcc always emits a warning for it :/ */ 485 /* this seems to work fine, but gcc always emits a warning for it :/ */
324 ecb_function_ void ecb_unreachable (void) ecb_noreturn; 486 ecb_inline void ecb_unreachable (void) ecb_noreturn;
325 ecb_function_ void ecb_unreachable (void) { } 487 ecb_inline void ecb_unreachable (void) { }
326#endif 488#endif
327 489
328/* try to tell the compiler that some condition is definitely true */ 490/* try to tell the compiler that some condition is definitely true */
329#define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0) 491#define ecb_assume(cond) if (!(cond)) ecb_unreachable (); else 0
330 492
331ecb_function_ unsigned char ecb_byteorder_helper (void) ecb_const; 493ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const;
332ecb_function_ unsigned char 494ecb_inline unsigned char
333ecb_byteorder_helper (void) 495ecb_byteorder_helper (void)
334{ 496{
335 const uint32_t u = 0x11223344; 497 /* the union code still generates code under pressure in gcc, */
336 return *(unsigned char *)&u; 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
337} 517}
338 518
339ecb_function_ ecb_bool ecb_big_endian (void) ecb_const; 519ecb_inline ecb_bool ecb_big_endian (void) ecb_const;
340ecb_function_ ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; } 520ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
341ecb_function_ ecb_bool ecb_little_endian (void) ecb_const; 521ecb_inline ecb_bool ecb_little_endian (void) ecb_const;
342ecb_function_ ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; } 522ecb_inline ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; }
343 523
344#if ECB_GCC_VERSION(3,0) || ECB_C99 524#if ECB_GCC_VERSION(3,0) || ECB_C99
345 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0)) 525 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
346#else 526#else
347 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n))) 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))
348#endif 544#endif
349 545
350#if ecb_cplusplus_does_not_suck 546#if ecb_cplusplus_does_not_suck
351 /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */ 547 /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */
352 template<typename T, int N> 548 template<typename T, int N>
… …
356 } 552 }
357#else 553#else
358 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0])) 554 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
359#endif 555#endif
360 556
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;
361#endif 617 #endif
362 618
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

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