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Comparing OpenCL/ecb.h (file contents):
Revision 1.1 by root, Thu May 3 23:30:08 2012 UTC vs.
Revision 1.2 by root, Thu Oct 11 05:02:54 2012 UTC

… …
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 0x00010002
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 enormous grief in return for some better fake benchmark numbers. 70 * causing enormous grief in return for some better fake benchmark numbers.
… …
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 */
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
66/*****************************************************************************/ 99/*****************************************************************************/
67 100
68/* ECB_NO_THREADS - ecb is not used by multiple threads, ever */ 101/* ECB_NO_THREADS - ecb is not used by multiple threads, ever */
69/* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */ 102/* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */
70 103
71#if ECB_NO_THREADS 104#if ECB_NO_THREADS
72# define ECB_NO_SMP 1 105 #define ECB_NO_SMP 1
73#endif 106#endif
74 107
75#if ECB_NO_THREADS || ECB_NO_SMP 108#if ECB_NO_SMP
76 #define ECB_MEMORY_FENCE do { } while (0) 109 #define ECB_MEMORY_FENCE do { } while (0)
77#endif 110#endif
78 111
79#ifndef ECB_MEMORY_FENCE 112#ifndef ECB_MEMORY_FENCE
80 #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110 113 #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
81 #if __i386 || __i386__ 114 #if __i386 || __i386__
82 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory") 115 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory")
83 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE /* non-lock xchg might be enough */ 116 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
84 #define ECB_MEMORY_FENCE_RELEASE do { } while (0) /* unlikely to change in future cpus */ 117 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
85 #elif __amd64 || __amd64__ || __x86_64 || __x86_64__ 118 #elif __amd64 || __amd64__ || __x86_64 || __x86_64__
86 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory") 119 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory")
87 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("lfence" : : : "memory") 120 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
88 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("sfence") /* play safe - not needed in any current cpu */ 121 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
89 #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ 122 #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__
90 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory") 123 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
91 #elif defined __ARM_ARCH_6__ || defined __ARM_ARCH_6J__ \ 124 #elif defined __ARM_ARCH_6__ || defined __ARM_ARCH_6J__ \
92 || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__ 125 || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__
93 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory") 126 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory")
94 #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \ 127 #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \
95 || defined __ARM_ARCH_7M__ || defined __ARM_ARCH_7R__ 128 || defined __ARM_ARCH_7M__ || defined __ARM_ARCH_7R__
96 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory") 129 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory")
97 #elif __sparc || __sparc__ 130 #elif __sparc || __sparc__
98 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad | " : : : "memory") 131 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad" : : : "memory")
99 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory") 132 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory")
100 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore") 133 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore")
101 #elif defined __s390__ || defined __s390x__ 134 #elif defined __s390__ || defined __s390x__
102 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory") 135 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory")
103 #elif defined __mips__ 136 #elif defined __mips__
104 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory") 137 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
105 #elif defined __alpha__ 138 #elif defined __alpha__
106 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mb" : : : "memory") 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")
107 #endif 145 #endif
108 #endif 146 #endif
109#endif 147#endif
110 148
111#ifndef ECB_MEMORY_FENCE 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
154 /* The __has_feature syntax from clang is so misdesigned that we cannot use it
155 * without risking compile time errors with other compilers. We *could*
156 * define our own ecb_clang_has_feature, but I just can't be bothered to work
157 * around this shit time and again.
158 * #elif defined __clang && __has_feature (cxx_atomic)
159 * // see comment below (stdatomic.h) about the C11 memory model.
160 * #define ECB_MEMORY_FENCE __c11_atomic_thread_fence (__ATOMIC_SEQ_CST)
161 */
162
112 #if ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__ 163 #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__
113 #define ECB_MEMORY_FENCE __sync_synchronize () 164 #define ECB_MEMORY_FENCE __sync_synchronize ()
114 /*#define ECB_MEMORY_FENCE_ACQUIRE ({ char dummy = 0; __sync_lock_test_and_set (&dummy, 1); }) */
115 /*#define ECB_MEMORY_FENCE_RELEASE ({ char dummy = 1; __sync_lock_release (&dummy ); }) */
116 #elif _MSC_VER >= 1400 /* VC++ 2005 */ 165 #elif _MSC_VER >= 1400 /* VC++ 2005 */
117 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier) 166 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
118 #define ECB_MEMORY_FENCE _ReadWriteBarrier () 167 #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
119 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */ 168 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
120 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier () 169 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
… …
130 #define ECB_MEMORY_FENCE __sync () 179 #define ECB_MEMORY_FENCE __sync ()
131 #endif 180 #endif
132#endif 181#endif
133 182
134#ifndef ECB_MEMORY_FENCE 183#ifndef ECB_MEMORY_FENCE
184 #if ECB_C11 && !defined __STDC_NO_ATOMICS__
185 /* we assume that these memory fences work on all variables/all memory accesses, */
186 /* not just C11 atomics and atomic accesses */
187 #include <stdatomic.h>
188 /* Unfortunately, neither gcc 4.7 nor clang 3.1 generate any instructions for */
189 /* any fence other than seq_cst, which isn't very efficient for us. */
190 /* Why that is, we don't know - either the C11 memory model is quite useless */
191 /* for most usages, or gcc and clang have a bug */
192 /* I *currently* lean towards the latter, and inefficiently implement */
193 /* all three of ecb's fences as a seq_cst fence */
194 #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_seq_cst)
195 #endif
196#endif
197
198#ifndef ECB_MEMORY_FENCE
135 #if !ECB_AVOID_PTHREADS 199 #if !ECB_AVOID_PTHREADS
136 /* 200 /*
137 * if you get undefined symbol references to pthread_mutex_lock, 201 * if you get undefined symbol references to pthread_mutex_lock,
138 * or failure to find pthread.h, then you should implement 202 * or failure to find pthread.h, then you should implement
139 * the ECB_MEMORY_FENCE operations for your cpu/compiler 203 * the ECB_MEMORY_FENCE operations for your cpu/compiler
… …
157 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE 221 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
158#endif 222#endif
159 223
160/*****************************************************************************/ 224/*****************************************************************************/
161 225
162#define ECB_C99 (__STDC_VERSION__ >= 199901L)
163
164#if __cplusplus 226#if __cplusplus
165 #define ecb_inline static inline 227 #define ecb_inline static inline
166#elif ECB_GCC_VERSION(2,5) 228#elif ECB_GCC_VERSION(2,5)
167 #define ecb_inline static __inline__ 229 #define ecb_inline static __inline__
168#elif ECB_C99 230#elif ECB_C99
… …
206#elif ECB_GCC_VERSION(3,0) 268#elif ECB_GCC_VERSION(3,0)
207 #define ecb_decltype(x) __typeof(x) 269 #define ecb_decltype(x) __typeof(x)
208#endif 270#endif
209 271
210#define ecb_noinline ecb_attribute ((__noinline__)) 272#define ecb_noinline ecb_attribute ((__noinline__))
211#define ecb_noreturn ecb_attribute ((__noreturn__))
212#define ecb_unused ecb_attribute ((__unused__)) 273#define ecb_unused ecb_attribute ((__unused__))
213#define ecb_const ecb_attribute ((__const__)) 274#define ecb_const ecb_attribute ((__const__))
214#define ecb_pure ecb_attribute ((__pure__)) 275#define ecb_pure ecb_attribute ((__pure__))
276
277#if ECB_C11
278 #define ecb_noreturn _Noreturn
279#else
280 #define ecb_noreturn ecb_attribute ((__noreturn__))
281#endif
215 282
216#if ECB_GCC_VERSION(4,3) 283#if ECB_GCC_VERSION(4,3)
217 #define ecb_artificial ecb_attribute ((__artificial__)) 284 #define ecb_artificial ecb_attribute ((__artificial__))
218 #define ecb_hot ecb_attribute ((__hot__)) 285 #define ecb_hot ecb_attribute ((__hot__))
219 #define ecb_cold ecb_attribute ((__cold__)) 286 #define ecb_cold ecb_attribute ((__cold__))
… …
310 377
311 return r + ecb_ld32 (x); 378 return r + ecb_ld32 (x);
312 } 379 }
313#endif 380#endif
314 381
382ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) ecb_const;
383ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) { return !(x & (x - 1)); }
384ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) ecb_const;
385ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) { return !(x & (x - 1)); }
386
315ecb_function_ uint8_t ecb_bitrev8 (uint8_t x) ecb_const; 387ecb_function_ uint8_t ecb_bitrev8 (uint8_t x) ecb_const;
316ecb_function_ uint8_t ecb_bitrev8 (uint8_t x) 388ecb_function_ uint8_t ecb_bitrev8 (uint8_t x)
317{ 389{
318 return ( (x * 0x0802U & 0x22110U) 390 return ( (x * 0x0802U & 0x22110U)
319 | (x * 0x8020U & 0x88440U)) * 0x10101U >> 16; 391 | (x * 0x8020U & 0x88440U)) * 0x10101U >> 16;
… …
403 ecb_inline void ecb_unreachable (void) ecb_noreturn; 475 ecb_inline void ecb_unreachable (void) ecb_noreturn;
404 ecb_inline void ecb_unreachable (void) { } 476 ecb_inline void ecb_unreachable (void) { }
405#endif 477#endif
406 478
407/* try to tell the compiler that some condition is definitely true */ 479/* try to tell the compiler that some condition is definitely true */
408#define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0) 480#define ecb_assume(cond) if (!(cond)) ecb_unreachable (); else 0
409 481
410ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const; 482ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const;
411ecb_inline unsigned char 483ecb_inline unsigned char
412ecb_byteorder_helper (void) 484ecb_byteorder_helper (void)
413{ 485{
414 const uint32_t u = 0x11223344; 486 /* the union code still generates code under pressure in gcc, */
415 return *(unsigned char *)&u; 487 /* but less than using pointers, and always seems to */
488 /* successfully return a constant. */
489 /* the reason why we have this horrible preprocessor mess */
490 /* is to avoid it in all cases, at least on common architectures */
491 /* or when using a recent enough gcc version (>= 4.6) */
492#if __i386 || __i386__ || _M_X86 || __amd64 || __amd64__ || _M_X64
493 return 0x44;
494#elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
495 return 0x44;
496#elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
497 return 0x11;
498#else
499 union
500 {
501 uint32_t i;
502 uint8_t c;
503 } u = { 0x11223344 };
504 return u.c;
505#endif
416} 506}
417 507
418ecb_inline ecb_bool ecb_big_endian (void) ecb_const; 508ecb_inline ecb_bool ecb_big_endian (void) ecb_const;
419ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; } 509ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
420ecb_inline ecb_bool ecb_little_endian (void) ecb_const; 510ecb_inline ecb_bool ecb_little_endian (void) ecb_const;
… …
451 } 541 }
452#else 542#else
453 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0])) 543 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
454#endif 544#endif
455 545
546/*******************************************************************************/
547/* floating point stuff, can be disabled by defining ECB_NO_LIBM */
548
549/* basically, everything uses "ieee pure-endian" floating point numbers */
550/* the only noteworthy exception is ancient armle, which uses order 43218765 */
551#if 0 \
552 || __i386 || __i386__ \
553 || __amd64 || __amd64__ || __x86_64 || __x86_64__ \
554 || __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ \
555 || defined __arm__ && defined __ARM_EABI__ \
556 || defined __s390__ || defined __s390x__ \
557 || defined __mips__ \
558 || defined __alpha__ \
559 || defined __hppa__ \
560 || defined __ia64__ \
561 || defined _M_IX86 || defined _M_AMD64 || defined _M_IA64
562 #define ECB_STDFP 1
563 #include <string.h> /* for memcpy */
564#else
565 #define ECB_STDFP 0
566 #include <math.h> /* for frexp*, ldexp* */
567#endif
568
569#ifndef ECB_NO_LIBM
570
571 /* convert a float to ieee single/binary32 */
572 ecb_function_ uint32_t ecb_float_to_binary32 (float x) ecb_const;
573 ecb_function_ uint32_t
574 ecb_float_to_binary32 (float x)
575 {
576 uint32_t r;
577
578 #if ECB_STDFP
579 memcpy (&r, &x, 4);
580 #else
581 /* slow emulation, works for anything but -0 */
582 uint32_t m;
583 int e;
584
585 if (x == 0e0f ) return 0x00000000U;
586 if (x > +3.40282346638528860e+38f) return 0x7f800000U;
587 if (x < -3.40282346638528860e+38f) return 0xff800000U;
588 if (x != x ) return 0x7fbfffffU;
589
590 m = frexpf (x, &e) * 0x1000000U;
591
592 r = m & 0x80000000U;
593
594 if (r)
595 m = -m;
596
597 if (e <= -126)
598 {
599 m &= 0xffffffU;
600 m >>= (-125 - e);
601 e = -126;
602 }
603
604 r |= (e + 126) << 23;
605 r |= m & 0x7fffffU;
456#endif 606 #endif
457 607
608 return r;
609 }
610
611 /* converts an ieee single/binary32 to a float */
612 ecb_function_ float ecb_binary32_to_float (uint32_t x) ecb_const;
613 ecb_function_ float
614 ecb_binary32_to_float (uint32_t x)
615 {
616 float r;
617
618 #if ECB_STDFP
619 memcpy (&r, &x, 4);
620 #else
621 /* emulation, only works for normals and subnormals and +0 */
622 int neg = x >> 31;
623 int e = (x >> 23) & 0xffU;
624
625 x &= 0x7fffffU;
626
627 if (e)
628 x |= 0x800000U;
629 else
630 e = 1;
631
632 /* we distrust ldexpf a bit and do the 2**-24 scaling by an extra multiply */
633 r = ldexpf (x * (0.5f / 0x800000U), e - 126);
634
635 r = neg ? -r : r;
636 #endif
637
638 return r;
639 }
640
641 /* convert a double to ieee double/binary64 */
642 ecb_function_ uint64_t ecb_double_to_binary64 (double x) ecb_const;
643 ecb_function_ uint64_t
644 ecb_double_to_binary64 (double x)
645 {
646 uint64_t r;
647
648 #if ECB_STDFP
649 memcpy (&r, &x, 8);
650 #else
651 /* slow emulation, works for anything but -0 */
652 uint64_t m;
653 int e;
654
655 if (x == 0e0 ) return 0x0000000000000000U;
656 if (x > +1.79769313486231470e+308) return 0x7ff0000000000000U;
657 if (x < -1.79769313486231470e+308) return 0xfff0000000000000U;
658 if (x != x ) return 0X7ff7ffffffffffffU;
659
660 m = frexp (x, &e) * 0x20000000000000U;
661
662 r = m & 0x8000000000000000;;
663
664 if (r)
665 m = -m;
666
667 if (e <= -1022)
668 {
669 m &= 0x1fffffffffffffU;
670 m >>= (-1021 - e);
671 e = -1022;
672 }
673
674 r |= ((uint64_t)(e + 1022)) << 52;
675 r |= m & 0xfffffffffffffU;
676 #endif
677
678 return r;
679 }
680
681 /* converts an ieee double/binary64 to a double */
682 ecb_function_ double ecb_binary64_to_double (uint64_t x) ecb_const;
683 ecb_function_ double
684 ecb_binary64_to_double (uint64_t x)
685 {
686 double r;
687
688 #if ECB_STDFP
689 memcpy (&r, &x, 8);
690 #else
691 /* emulation, only works for normals and subnormals and +0 */
692 int neg = x >> 63;
693 int e = (x >> 52) & 0x7ffU;
694
695 x &= 0xfffffffffffffU;
696
697 if (e)
698 x |= 0x10000000000000U;
699 else
700 e = 1;
701
702 /* we distrust ldexp a bit and do the 2**-53 scaling by an extra multiply */
703 r = ldexp (x * (0.5 / 0x10000000000000U), e - 1022);
704
705 r = neg ? -r : r;
706 #endif
707
708 return r;
709 }
710
711#endif
712
713#endif
714

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