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Comparing libecb/ecb.h (file contents):
Revision 1.88 by root, Mon May 28 08:40:25 2012 UTC vs.
Revision 1.120 by root, Sat Oct 26 09:13:54 2013 UTC

… …
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 */ 33/* 16 bits major, 16 bits minor */
34#define ECB_VERSION 0x00010001 34#define ECB_VERSION 0x00010003
35 35
36#ifdef _WIN32 36#ifdef _WIN32
37 typedef signed char int8_t; 37 typedef signed char int8_t;
38 typedef unsigned char uint8_t; 38 typedef unsigned char uint8_t;
39 typedef signed short int16_t; 39 typedef signed short int16_t;
… …
63 #else 63 #else
64 #define ECB_PTRSIZE 4 64 #define ECB_PTRSIZE 4
65 #endif 65 #endif
66#endif 66#endif
67 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
68/* many compilers define _GNUC_ to some versions but then only implement 77/* many compilers define _GNUC_ to some versions but then only implement
69 * what their idiot authors think are the "more important" extensions, 78 * what their idiot authors think are the "more important" extensions,
70 * causing enormous grief in return for some better fake benchmark numbers. 79 * causing enormous grief in return for some better fake benchmark numbers.
71 * or so. 80 * or so.
72 * 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
… …
78 #else 87 #else
79 #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)))
80 #endif 89 #endif
81#endif 90#endif
82 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
83/*****************************************************************************/ 108/*****************************************************************************/
84 109
85/* ECB_NO_THREADS - ecb is not used by multiple threads, ever */ 110/* ECB_NO_THREADS - ecb is not used by multiple threads, ever */
86/* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */ 111/* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */
87 112
88#if ECB_NO_THREADS 113#if ECB_NO_THREADS
89# define ECB_NO_SMP 1 114 #define ECB_NO_SMP 1
90#endif 115#endif
91 116
92#if ECB_NO_THREADS || ECB_NO_SMP 117#if ECB_NO_SMP
93 #define ECB_MEMORY_FENCE do { } while (0) 118 #define ECB_MEMORY_FENCE do { } while (0)
94#endif 119#endif
95 120
96#ifndef ECB_MEMORY_FENCE 121#ifndef ECB_MEMORY_FENCE
97 #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110 122 #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
98 #if __i386 || __i386__ 123 #if __i386 || __i386__
99 #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")
100 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE /* non-lock xchg might be enough */ 125 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
101 #define ECB_MEMORY_FENCE_RELEASE do { } while (0) /* unlikely to change in future cpus */ 126 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
102 #elif __amd64 || __amd64__ || __x86_64 || __x86_64__ 127 #elif __amd64 || __amd64__ || __x86_64 || __x86_64__
103 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory") 128 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory")
104 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("lfence" : : : "memory") 129 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
105 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("sfence") /* play safe - not needed in any current cpu */ 130 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
106 #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ 131 #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__
107 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory") 132 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
108 #elif defined __ARM_ARCH_6__ || defined __ARM_ARCH_6J__ \ 133 #elif defined __ARM_ARCH_6__ || defined __ARM_ARCH_6J__ \
109 || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__ 134 || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__
110 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory") 135 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory")
111 #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \ 136 #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \
112 || defined __ARM_ARCH_7M__ || defined __ARM_ARCH_7R__ 137 || defined __ARM_ARCH_7M__ || defined __ARM_ARCH_7R__
113 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory") 138 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory")
114 #elif __sparc || __sparc__ 139 #elif __sparc || __sparc__
115 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad | " : : : "memory") 140 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad" : : : "memory")
116 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory") 141 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory")
117 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore") 142 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore")
118 #elif defined __s390__ || defined __s390x__ 143 #elif defined __s390__ || defined __s390x__
119 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory") 144 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory")
120 #elif defined __mips__ 145 #elif defined __mips__
146 /* GNU/Linux emulates sync on mips1 architectures, so we force its use */
147 /* anybody else who still uses mips1 is supposed to send in their version, with detection code. */
121 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory") 148 #define ECB_MEMORY_FENCE __asm__ __volatile__ (".set mips2; sync; .set mips0" : : : "memory")
122 #elif defined __alpha__ 149 #elif defined __alpha__
123 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mb" : : : "memory") 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 #elif defined __m68k__
157 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory")
158 #elif defined __m88k__
159 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("tb1 0,%%r0,128" : : : "memory")
160 #elif defined __sh__
161 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory")
124 #endif 162 #endif
125 #endif 163 #endif
126#endif 164#endif
127 165
128#ifndef ECB_MEMORY_FENCE 166#ifndef ECB_MEMORY_FENCE
167 #if ECB_GCC_VERSION(4,7)
168 /* see comment below (stdatomic.h) about the C11 memory model. */
169 #define ECB_MEMORY_FENCE __atomic_thread_fence (__ATOMIC_SEQ_CST)
170
171 /* The __has_feature syntax from clang is so misdesigned that we cannot use it
172 * without risking compile time errors with other compilers. We *could*
173 * define our own ecb_clang_has_feature, but I just can't be bothered to work
174 * around this shit time and again.
175 * #elif defined __clang && __has_feature (cxx_atomic)
176 * // see comment below (stdatomic.h) about the C11 memory model.
177 * #define ECB_MEMORY_FENCE __c11_atomic_thread_fence (__ATOMIC_SEQ_CST)
178 */
179
129 #if ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__ 180 #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__
130 #define ECB_MEMORY_FENCE __sync_synchronize () 181 #define ECB_MEMORY_FENCE __sync_synchronize ()
131 /*#define ECB_MEMORY_FENCE_ACQUIRE ({ char dummy = 0; __sync_lock_test_and_set (&dummy, 1); }) */
132 /*#define ECB_MEMORY_FENCE_RELEASE ({ char dummy = 1; __sync_lock_release (&dummy ); }) */
133 #elif _MSC_VER >= 1400 /* VC++ 2005 */ 182 #elif _MSC_VER >= 1400 /* VC++ 2005 */
134 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier) 183 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
135 #define ECB_MEMORY_FENCE _ReadWriteBarrier () 184 #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
136 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */ 185 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
137 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier () 186 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
… …
147 #define ECB_MEMORY_FENCE __sync () 196 #define ECB_MEMORY_FENCE __sync ()
148 #endif 197 #endif
149#endif 198#endif
150 199
151#ifndef ECB_MEMORY_FENCE 200#ifndef ECB_MEMORY_FENCE
201 #if ECB_C11 && !defined __STDC_NO_ATOMICS__
202 /* we assume that these memory fences work on all variables/all memory accesses, */
203 /* not just C11 atomics and atomic accesses */
204 #include <stdatomic.h>
205 /* Unfortunately, neither gcc 4.7 nor clang 3.1 generate any instructions for */
206 /* any fence other than seq_cst, which isn't very efficient for us. */
207 /* Why that is, we don't know - either the C11 memory model is quite useless */
208 /* for most usages, or gcc and clang have a bug */
209 /* I *currently* lean towards the latter, and inefficiently implement */
210 /* all three of ecb's fences as a seq_cst fence */
211 #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_seq_cst)
212 #endif
213#endif
214
215#ifndef ECB_MEMORY_FENCE
152 #if !ECB_AVOID_PTHREADS 216 #if !ECB_AVOID_PTHREADS
153 /* 217 /*
154 * if you get undefined symbol references to pthread_mutex_lock, 218 * if you get undefined symbol references to pthread_mutex_lock,
155 * or failure to find pthread.h, then you should implement 219 * or failure to find pthread.h, then you should implement
156 * the ECB_MEMORY_FENCE operations for your cpu/compiler 220 * the ECB_MEMORY_FENCE operations for your cpu/compiler
… …
174 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE 238 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
175#endif 239#endif
176 240
177/*****************************************************************************/ 241/*****************************************************************************/
178 242
179#define ECB_C99 (__STDC_VERSION__ >= 199901L)
180
181#if __cplusplus 243#if __cplusplus
182 #define ecb_inline static inline 244 #define ecb_inline static inline
183#elif ECB_GCC_VERSION(2,5) 245#elif ECB_GCC_VERSION(2,5)
184 #define ecb_inline static __inline__ 246 #define ecb_inline static __inline__
185#elif ECB_C99 247#elif ECB_C99
… …
223#elif ECB_GCC_VERSION(3,0) 285#elif ECB_GCC_VERSION(3,0)
224 #define ecb_decltype(x) __typeof(x) 286 #define ecb_decltype(x) __typeof(x)
225#endif 287#endif
226 288
227#define ecb_noinline ecb_attribute ((__noinline__)) 289#define ecb_noinline ecb_attribute ((__noinline__))
228#define ecb_noreturn ecb_attribute ((__noreturn__))
229#define ecb_unused ecb_attribute ((__unused__)) 290#define ecb_unused ecb_attribute ((__unused__))
230#define ecb_const ecb_attribute ((__const__)) 291#define ecb_const ecb_attribute ((__const__))
231#define ecb_pure ecb_attribute ((__pure__)) 292#define ecb_pure ecb_attribute ((__pure__))
293
294#if ECB_C11
295 #define ecb_noreturn _Noreturn
296#else
297 #define ecb_noreturn ecb_attribute ((__noreturn__))
298#endif
232 299
233#if ECB_GCC_VERSION(4,3) 300#if ECB_GCC_VERSION(4,3)
234 #define ecb_artificial ecb_attribute ((__artificial__)) 301 #define ecb_artificial ecb_attribute ((__artificial__))
235 #define ecb_hot ecb_attribute ((__hot__)) 302 #define ecb_hot ecb_attribute ((__hot__))
236 #define ecb_cold ecb_attribute ((__cold__)) 303 #define ecb_cold ecb_attribute ((__cold__))
… …
425 ecb_inline void ecb_unreachable (void) ecb_noreturn; 492 ecb_inline void ecb_unreachable (void) ecb_noreturn;
426 ecb_inline void ecb_unreachable (void) { } 493 ecb_inline void ecb_unreachable (void) { }
427#endif 494#endif
428 495
429/* try to tell the compiler that some condition is definitely true */ 496/* try to tell the compiler that some condition is definitely true */
430#define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0) 497#define ecb_assume(cond) if (!(cond)) ecb_unreachable (); else 0
431 498
432ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const; 499ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const;
433ecb_inline unsigned char 500ecb_inline unsigned char
434ecb_byteorder_helper (void) 501ecb_byteorder_helper (void)
435{ 502{
436 const uint32_t u = 0x11223344; 503 /* the union code still generates code under pressure in gcc, */
437 return *(unsigned char *)&u; 504 /* but less than using pointers, and always seems to */
505 /* successfully return a constant. */
506 /* the reason why we have this horrible preprocessor mess */
507 /* is to avoid it in all cases, at least on common architectures */
508 /* or when using a recent enough gcc version (>= 4.6) */
509#if __i386 || __i386__ || _M_X86 || __amd64 || __amd64__ || _M_X64
510 return 0x44;
511#elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
512 return 0x44;
513#elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
514 return 0x11;
515#else
516 union
517 {
518 uint32_t i;
519 uint8_t c;
520 } u = { 0x11223344 };
521 return u.c;
522#endif
438} 523}
439 524
440ecb_inline ecb_bool ecb_big_endian (void) ecb_const; 525ecb_inline ecb_bool ecb_big_endian (void) ecb_const;
441ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; } 526ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
442ecb_inline ecb_bool ecb_little_endian (void) ecb_const; 527ecb_inline ecb_bool ecb_little_endian (void) ecb_const;
… …
473 } 558 }
474#else 559#else
475 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0])) 560 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
476#endif 561#endif
477 562
563/*******************************************************************************/
564/* floating point stuff, can be disabled by defining ECB_NO_LIBM */
565
566/* basically, everything uses "ieee pure-endian" floating point numbers */
567/* the only noteworthy exception is ancient armle, which uses order 43218765 */
568#if 0 \
569 || __i386 || __i386__ \
570 || __amd64 || __amd64__ || __x86_64 || __x86_64__ \
571 || __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ \
572 || defined __arm__ && defined __ARM_EABI__ \
573 || defined __s390__ || defined __s390x__ \
574 || defined __mips__ \
575 || defined __alpha__ \
576 || defined __hppa__ \
577 || defined __ia64__ \
578 || defined __m68k__ \
579 || defined __m88k__ \
580 || defined __sh__ \
581 || defined _M_IX86 || defined _M_AMD64 || defined _M_IA64
582 #define ECB_STDFP 1
583 #include <string.h> /* for memcpy */
584#else
585 #define ECB_STDFP 0
586#endif
587
588#ifndef ECB_NO_LIBM
589
590 #include <math.h> /* for frexp*, ldexp* */
591
592 /* converts an ieee half/binary16 to a float */
593 ecb_function_ float ecb_binary16_to_float (uint16_t x) ecb_const;
594 ecb_function_ float
595 ecb_binary16_to_float (uint16_t x)
596 {
597 int e = (x >> 10) & 0x1f;
598 int m = x & 0x3ff;
599 float r;
600
601 if (!e)
602 r = ldexpf (m , -24);
603 else if (e != 31)
604 r = ldexpf (m + 0x400, e - 25);
605 else if (m)
606 #ifdef NAN
607 r = NAN;
608 #endif
609 else
610 r = INFINITY;
611
612 return x & 0x8000 ? -r : r;
613 }
614
615 /* convert a float to ieee single/binary32 */
616 ecb_function_ uint32_t ecb_float_to_binary32 (float x) ecb_const;
617 ecb_function_ uint32_t
618 ecb_float_to_binary32 (float x)
619 {
620 uint32_t r;
621
622 #if ECB_STDFP
623 memcpy (&r, &x, 4);
624 #else
625 /* slow emulation, works for anything but -0 */
626 uint32_t m;
627 int e;
628
629 if (x == 0e0f ) return 0x00000000U;
630 if (x > +3.40282346638528860e+38f) return 0x7f800000U;
631 if (x < -3.40282346638528860e+38f) return 0xff800000U;
632 if (x != x ) return 0x7fbfffffU;
633
634 m = frexpf (x, &e) * 0x1000000U;
635
636 r = m & 0x80000000U;
637
638 if (r)
639 m = -m;
640
641 if (e <= -126)
642 {
643 m &= 0xffffffU;
644 m >>= (-125 - e);
645 e = -126;
646 }
647
648 r |= (e + 126) << 23;
649 r |= m & 0x7fffffU;
478#endif 650 #endif
479 651
652 return r;
653 }
654
655 /* converts an ieee single/binary32 to a float */
656 ecb_function_ float ecb_binary32_to_float (uint32_t x) ecb_const;
657 ecb_function_ float
658 ecb_binary32_to_float (uint32_t x)
659 {
660 float r;
661
662 #if ECB_STDFP
663 memcpy (&r, &x, 4);
664 #else
665 /* emulation, only works for normals and subnormals and +0 */
666 int neg = x >> 31;
667 int e = (x >> 23) & 0xffU;
668
669 x &= 0x7fffffU;
670
671 if (e)
672 x |= 0x800000U;
673 else
674 e = 1;
675
676 /* we distrust ldexpf a bit and do the 2**-24 scaling by an extra multiply */
677 r = ldexpf (x * (0.5f / 0x800000U), e - 126);
678
679 r = neg ? -r : r;
680 #endif
681
682 return r;
683 }
684
685 /* convert a double to ieee double/binary64 */
686 ecb_function_ uint64_t ecb_double_to_binary64 (double x) ecb_const;
687 ecb_function_ uint64_t
688 ecb_double_to_binary64 (double x)
689 {
690 uint64_t r;
691
692 #if ECB_STDFP
693 memcpy (&r, &x, 8);
694 #else
695 /* slow emulation, works for anything but -0 */
696 uint64_t m;
697 int e;
698
699 if (x == 0e0 ) return 0x0000000000000000U;
700 if (x > +1.79769313486231470e+308) return 0x7ff0000000000000U;
701 if (x < -1.79769313486231470e+308) return 0xfff0000000000000U;
702 if (x != x ) return 0X7ff7ffffffffffffU;
703
704 m = frexp (x, &e) * 0x20000000000000U;
705
706 r = m & 0x8000000000000000;;
707
708 if (r)
709 m = -m;
710
711 if (e <= -1022)
712 {
713 m &= 0x1fffffffffffffU;
714 m >>= (-1021 - e);
715 e = -1022;
716 }
717
718 r |= ((uint64_t)(e + 1022)) << 52;
719 r |= m & 0xfffffffffffffU;
720 #endif
721
722 return r;
723 }
724
725 /* converts an ieee double/binary64 to a double */
726 ecb_function_ double ecb_binary64_to_double (uint64_t x) ecb_const;
727 ecb_function_ double
728 ecb_binary64_to_double (uint64_t x)
729 {
730 double r;
731
732 #if ECB_STDFP
733 memcpy (&r, &x, 8);
734 #else
735 /* emulation, only works for normals and subnormals and +0 */
736 int neg = x >> 63;
737 int e = (x >> 52) & 0x7ffU;
738
739 x &= 0xfffffffffffffU;
740
741 if (e)
742 x |= 0x10000000000000U;
743 else
744 e = 1;
745
746 /* we distrust ldexp a bit and do the 2**-53 scaling by an extra multiply */
747 r = ldexp (x * (0.5 / 0x10000000000000U), e - 1022);
748
749 r = neg ? -r : r;
750 #endif
751
752 return r;
753 }
754
755#endif
756
757#endif
758

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