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Comparing libecb/ecb.h (file contents):
Revision 1.51 by root, Wed Jun 22 15:18:06 2011 UTC vs.
Revision 1.109 by root, Fri Jun 29 14:05:50 2012 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 0x00010001
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
49#endif 66#endif
50 67
51/* many compilers define _GNUC_ to some versions but then only implement 68/* many compilers define _GNUC_ to some versions but then only implement
52 * what their idiot authors think are the "more important" extensions, 69 * what their idiot authors think are the "more important" extensions,
53 * causing enourmous grief in return for some better fake benchmark numbers. 70 * causing enormous grief in return for some better fake benchmark numbers.
54 * or so. 71 * or so.
55 * we try to detect these and simply assume they are not gcc - if they have 72 * 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. 73 * an issue with that they should have done it right in the first place.
57 */ 74 */
58#ifndef ECB_GCC_VERSION 75#ifndef ECB_GCC_VERSION
59 #if !defined(__GNUC_MINOR__) || defined(__INTEL_COMPILER) || defined(__SUNPRO_C) || defined(__SUNPRO_CC) || defined(__llvm__) || defined(__clang__) 76 #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 77 #define ECB_GCC_VERSION(major,minor) 0
61 #else 78 #else
62 #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor))) 79 #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
63 #endif 80 #endif
64#endif 81#endif
65 82
83#define ECB_C (__STDC__+0) /* this assumes that __STDC__ is either empty or a number */
66#define ECB_C99 (__STDC_VERSION__ >= 199901L) 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/*****************************************************************************/
67 218
68#if __cplusplus 219#if __cplusplus
69 #define ecb_inline static inline 220 #define ecb_inline static inline
70#elif ECB_GCC_VERSION(2,5) 221#elif ECB_GCC_VERSION(2,5)
71 #define ecb_inline static __inline__ 222 #define ecb_inline static __inline__
… …
110#elif ECB_GCC_VERSION(3,0) 261#elif ECB_GCC_VERSION(3,0)
111 #define ecb_decltype(x) __typeof(x) 262 #define ecb_decltype(x) __typeof(x)
112#endif 263#endif
113 264
114#define ecb_noinline ecb_attribute ((__noinline__)) 265#define ecb_noinline ecb_attribute ((__noinline__))
115#define ecb_noreturn ecb_attribute ((__noreturn__))
116#define ecb_unused ecb_attribute ((__unused__)) 266#define ecb_unused ecb_attribute ((__unused__))
117#define ecb_const ecb_attribute ((__const__)) 267#define ecb_const ecb_attribute ((__const__))
118#define ecb_pure ecb_attribute ((__pure__)) 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
119 275
120#if ECB_GCC_VERSION(4,3) 276#if ECB_GCC_VERSION(4,3)
121 #define ecb_artificial ecb_attribute ((__artificial__)) 277 #define ecb_artificial ecb_attribute ((__artificial__))
122 #define ecb_hot ecb_attribute ((__hot__)) 278 #define ecb_hot ecb_attribute ((__hot__))
123 #define ecb_cold ecb_attribute ((__cold__)) 279 #define ecb_cold ecb_attribute ((__cold__))
… …
189 x *= 0x01010101; 345 x *= 0x01010101;
190 346
191 return x >> 24; 347 return x >> 24;
192 } 348 }
193 349
194 /* you have the choice beetween something with a table lookup, */
195 /* something using lots of bit arithmetic and a simple loop */
196 /* we went for the loop */
197 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const; 350 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
198 ecb_function_ int ecb_ld32 (uint32_t x) 351 ecb_function_ int ecb_ld32 (uint32_t x)
199 { 352 {
200 int r = 0; 353 int r = 0;
201 354
… …
216 if (x >> 32) { x >>= 32; r += 32; } 369 if (x >> 32) { x >>= 32; r += 32; }
217 370
218 return r + ecb_ld32 (x); 371 return r + ecb_ld32 (x);
219 } 372 }
220#endif 373#endif
374
375ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) ecb_const;
376ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) { return !(x & (x - 1)); }
377ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) ecb_const;
378ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) { return !(x & (x - 1)); }
379
380ecb_function_ uint8_t ecb_bitrev8 (uint8_t x) ecb_const;
381ecb_function_ uint8_t ecb_bitrev8 (uint8_t x)
382{
383 return ( (x * 0x0802U & 0x22110U)
384 | (x * 0x8020U & 0x88440U)) * 0x10101U >> 16;
385}
386
387ecb_function_ uint16_t ecb_bitrev16 (uint16_t x) ecb_const;
388ecb_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
398ecb_function_ uint32_t ecb_bitrev32 (uint32_t x) ecb_const;
399ecb_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}
221 409
222/* popcount64 is only available on 64 bit cpus as gcc builtin */ 410/* popcount64 is only available on 64 bit cpus as gcc builtin */
223/* so for this version we are lazy */ 411/* so for this version we are lazy */
224ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const; 412ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const;
225ecb_function_ int 413ecb_function_ int
… …
275 463
276#if ECB_GCC_VERSION(4,5) 464#if ECB_GCC_VERSION(4,5)
277 #define ecb_unreachable() __builtin_unreachable () 465 #define ecb_unreachable() __builtin_unreachable ()
278#else 466#else
279 /* this seems to work fine, but gcc always emits a warning for it :/ */ 467 /* this seems to work fine, but gcc always emits a warning for it :/ */
280 ecb_function_ void ecb_unreachable (void) ecb_noreturn; 468 ecb_inline void ecb_unreachable (void) ecb_noreturn;
281 ecb_function_ void ecb_unreachable (void) { } 469 ecb_inline void ecb_unreachable (void) { }
282#endif 470#endif
283 471
284/* try to tell the compiler that some condition is definitely true */ 472/* try to tell the compiler that some condition is definitely true */
285#define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0) 473#define ecb_assume(cond) if (!(cond)) ecb_unreachable (); else 0
286 474
287ecb_function_ unsigned char ecb_byteorder_helper (void) ecb_const; 475ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const;
288ecb_function_ unsigned char 476ecb_inline unsigned char
289ecb_byteorder_helper (void) 477ecb_byteorder_helper (void)
290{ 478{
291 const uint32_t u = 0x11223344; 479 /* the union code still generates code under pressure in gcc, */
292 return *(unsigned char *)&u; 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
293} 499}
294 500
295ecb_function_ ecb_bool ecb_big_endian (void) ecb_const; 501ecb_inline ecb_bool ecb_big_endian (void) ecb_const;
296ecb_function_ ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; } 502ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
297ecb_function_ ecb_bool ecb_little_endian (void) ecb_const; 503ecb_inline ecb_bool ecb_little_endian (void) ecb_const;
298ecb_function_ ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; } 504ecb_inline ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; }
299 505
300#if ECB_GCC_VERSION(3,0) || ECB_C99 506#if ECB_GCC_VERSION(3,0) || ECB_C99
301 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0)) 507 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
302#else 508#else
303 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n))) 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))
304#endif 526#endif
305 527
306#if ecb_cplusplus_does_not_suck 528#if ecb_cplusplus_does_not_suck
307 /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */ 529 /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */
308 template<typename T, int N> 530 template<typename T, int N>
… …
312 } 534 }
313#else 535#else
314 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0])) 536 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
315#endif 537#endif
316 538
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 #include <math.h> /* for frexp*, ldexp* */
560#endif
561
562#ifndef ECB_NO_LIBM
563
564 /* convert a float to ieee single/binary32 */
565 ecb_function_ uint32_t ecb_float_to_binary32 (float x) ecb_const;
566 ecb_function_ uint32_t
567 ecb_float_to_binary32 (float x)
568 {
569 uint32_t r;
570
571 #if ECB_STDFP
572 memcpy (&r, &x, 4);
573 #else
574 /* slow emulation, works for anything but -0 */
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;
317#endif 599 #endif
318 600
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 int neg = x >> 31;
616 int e = (x >> 23) & 0xffU;
617
618 x &= 0x7fffffU;
619
620 if (e)
621 x |= 0x800000U;
622 else
623 e = 1;
624
625 /* we distrust ldexpf a bit and do the 2**-24 scaling by an extra multiply */
626 r = ldexpf (x * (0.5f / 0x800000U), e - 126);
627
628 r = neg ? -r : r;
629 #endif
630
631 return r;
632 }
633
634 /* convert a double to ieee double/binary64 */
635 ecb_function_ uint64_t ecb_double_to_binary64 (double x) ecb_const;
636 ecb_function_ uint64_t
637 ecb_double_to_binary64 (double x)
638 {
639 uint64_t r;
640
641 #if ECB_STDFP
642 memcpy (&r, &x, 8);
643 #else
644 /* slow emulation, works for anything but -0 */
645 uint64_t m;
646 int e;
647
648 if (x == 0e0 ) return 0x0000000000000000U;
649 if (x > +1.79769313486231470e+308) return 0x7ff0000000000000U;
650 if (x < -1.79769313486231470e+308) return 0xfff0000000000000U;
651 if (x != x ) return 0X7ff7ffffffffffffU;
652
653 m = frexp (x, &e) * 0x20000000000000U;
654
655 r = m & 0x8000000000000000;;
656
657 if (r)
658 m = -m;
659
660 if (e <= -1022)
661 {
662 m &= 0x1fffffffffffffU;
663 m >>= (-1021 - e);
664 e = -1022;
665 }
666
667 r |= ((uint64_t)(e + 1022)) << 52;
668 r |= m & 0xfffffffffffffU;
669 #endif
670
671 return r;
672 }
673
674 /* converts an ieee double/binary64 to a double */
675 ecb_function_ double ecb_binary64_to_double (uint64_t x) ecb_const;
676 ecb_function_ double
677 ecb_binary64_to_double (uint64_t x)
678 {
679 double r;
680
681 #if ECB_STDFP
682 memcpy (&r, &x, 8);
683 #else
684 /* emulation, only works for normals and subnormals and +0 */
685 int neg = x >> 63;
686 int e = (x >> 52) & 0x7ffU;
687
688 x &= 0xfffffffffffffU;
689
690 if (e)
691 x |= 0x10000000000000U;
692 else
693 e = 1;
694
695 /* we distrust ldexp a bit and do the 2**-53 scaling by an extra multiply */
696 r = ldexp (x * (0.5 / 0x10000000000000U), e - 1022);
697
698 r = neg ? -r : r;
699 #endif
700
701 return r;
702 }
703
704#endif
705
706#endif
707

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