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Comparing libeio/ecb.h (file contents):
Revision 1.13 by root, Sat Jun 2 20:13:26 2012 UTC vs.
Revision 1.19 by root, Fri Jan 24 23:46:17 2014 UTC

1/* 1/*
2 * libecb - http://software.schmorp.de/pkg/libecb 2 * libecb - http://software.schmorp.de/pkg/libecb
3 * 3 *
4 * Copyright (©) 2009-2012 Marc Alexander Lehmann <libecb@schmorp.de> 4 * Copyright (©) 2009-2013 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:
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;
54 #else 54 #else
55 #define ECB_PTRSIZE 4 55 #define ECB_PTRSIZE 4
56 typedef uint32_t uintptr_t; 56 typedef uint32_t uintptr_t;
57 typedef int32_t intptr_t; 57 typedef int32_t intptr_t;
58 #endif 58 #endif
59 typedef intptr_t ptrdiff_t;
60#else 59#else
61 #include <inttypes.h> 60 #include <inttypes.h>
62 #if UINTMAX_MAX > 0xffffffffU 61 #if UINTMAX_MAX > 0xffffffffU
63 #define ECB_PTRSIZE 8 62 #define ECB_PTRSIZE 8
64 #else 63 #else
65 #define ECB_PTRSIZE 4 64 #define ECB_PTRSIZE 4
65 #endif
66#endif
67
68/* work around x32 idiocy by defining proper macros */
69#if __amd64 || __x86_64 || _M_AMD64 || _M_X64
70 #if _ILP32
71 #define ECB_AMD64_X32 1
72 #else
73 #define ECB_AMD64 1
66 #endif 74 #endif
67#endif 75#endif
68 76
69/* many compilers define _GNUC_ to some versions but then only implement 77/* many compilers define _GNUC_ to some versions but then only implement
70 * what their idiot authors think are the "more important" extensions, 78 * what their idiot authors think are the "more important" extensions,
79 #else 87 #else
80 #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)))
81 #endif 89 #endif
82#endif 90#endif
83 91
84#define ECB_C (__STDC__+0) /* this assumes that __STDC__ is either empty or a number */
85#define ECB_C99 (__STDC_VERSION__ >= 199901L)
86#define ECB_C11 (__STDC_VERSION__ >= 201112L)
87#define ECB_CPP (__cplusplus+0) 92#define ECB_CPP (__cplusplus+0)
88#define ECB_CPP11 (__cplusplus >= 201103L) 93#define ECB_CPP11 (__cplusplus >= 201103L)
94
95#if ECB_CPP
96 #define ECB_C 0
97 #define ECB_STDC_VERSION 0
98#else
99 #define ECB_C 1
100 #define ECB_STDC_VERSION __STDC_VERSION__
101#endif
102
103#define ECB_C99 (ECB_STDC_VERSION >= 199901L)
104#define ECB_C11 (ECB_STDC_VERSION >= 201112L)
105
106#if ECB_CPP
107 #define ECB_EXTERN_C extern "C"
108 #define ECB_EXTERN_C_BEG ECB_EXTERN_C {
109 #define ECB_EXTERN_C_END }
110#else
111 #define ECB_EXTERN_C extern
112 #define ECB_EXTERN_C_BEG
113 #define ECB_EXTERN_C_END
114#endif
89 115
90/*****************************************************************************/ 116/*****************************************************************************/
91 117
92/* ECB_NO_THREADS - ecb is not used by multiple threads, ever */ 118/* ECB_NO_THREADS - ecb is not used by multiple threads, ever */
93/* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */ 119/* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */
116 || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__ 142 || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__
117 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory") 143 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory")
118 #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \ 144 #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \
119 || defined __ARM_ARCH_7M__ || defined __ARM_ARCH_7R__ 145 || defined __ARM_ARCH_7M__ || defined __ARM_ARCH_7R__
120 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory") 146 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory")
121 #elif __sparc || __sparc__ 147 #elif (__sparc || __sparc__) && !__sparcv8
122 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad" : : : "memory") 148 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad" : : : "memory")
123 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory") 149 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory")
124 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore") 150 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore")
125 #elif defined __s390__ || defined __s390x__ 151 #elif defined __s390__ || defined __s390x__
126 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory") 152 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory")
127 #elif defined __mips__ 153 #elif defined __mips__
154 /* GNU/Linux emulates sync on mips1 architectures, so we force its use */
155 /* anybody else who still uses mips1 is supposed to send in their version, with detection code. */
128 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory") 156 #define ECB_MEMORY_FENCE __asm__ __volatile__ (".set mips2; sync; .set mips0" : : : "memory")
129 #elif defined __alpha__ 157 #elif defined __alpha__
130 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mb" : : : "memory") 158 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mb" : : : "memory")
131 #elif defined __hppa__ 159 #elif defined __hppa__
132 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory") 160 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory")
133 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("") 161 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
134 #elif defined __ia64__ 162 #elif defined __ia64__
135 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mf" : : : "memory") 163 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mf" : : : "memory")
164 #elif defined __m68k__
165 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory")
166 #elif defined __m88k__
167 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("tb1 0,%%r0,128" : : : "memory")
168 #elif defined __sh__
169 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory")
136 #endif 170 #endif
137 #endif 171 #endif
138#endif 172#endif
139 173
140#ifndef ECB_MEMORY_FENCE 174#ifndef ECB_MEMORY_FENCE
141 #if ECB_GCC_VERSION(4,7) 175 #if ECB_GCC_VERSION(4,7)
142 /* see comment below (stdatomic.h) about the C11 memory model. */ 176 /* see comment below (stdatomic.h) about the C11 memory model. */
143 #define ECB_MEMORY_FENCE __atomic_thread_fence (__ATOMIC_SEQ_CST) 177 #define ECB_MEMORY_FENCE __atomic_thread_fence (__ATOMIC_SEQ_CST)
178 #define ECB_MEMORY_FENCE_ACQUIRE __atomic_thread_fence (__ATOMIC_ACQUIRE)
179 #define ECB_MEMORY_FENCE_RELEASE __atomic_thread_fence (__ATOMIC_RELEASE)
180
181 /* The __has_feature syntax from clang is so misdesigned that we cannot use it
182 * without risking compile time errors with other compilers. We *could*
183 * define our own ecb_clang_has_feature, but I just can't be bothered to work
184 * around this shit time and again.
144 #elif defined __clang && __has_feature (cxx_atomic) 185 * #elif defined __clang && __has_feature (cxx_atomic)
145 /* see comment below (stdatomic.h) about the C11 memory model. */ 186 * // see comment below (stdatomic.h) about the C11 memory model.
146 #define ECB_MEMORY_FENCE __c11_atomic_thread_fence (__ATOMIC_SEQ_CST) 187 * #define ECB_MEMORY_FENCE __c11_atomic_thread_fence (__ATOMIC_SEQ_CST)
188 * #define ECB_MEMORY_FENCE_ACQUIRE __c11_atomic_thread_fence (__ATOMIC_ACQUIRE)
189 * #define ECB_MEMORY_FENCE_RELEASE __c11_atomic_thread_fence (__ATOMIC_RELEASE)
190 */
191
147 #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__ 192 #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__
148 #define ECB_MEMORY_FENCE __sync_synchronize () 193 #define ECB_MEMORY_FENCE __sync_synchronize ()
194 #elif _MSC_VER >= 1500 /* VC++ 2008 */
195 /* apparently, microsoft broke all the memory barrier stuff in Visual Studio 2008... */
196 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
197 #define ECB_MEMORY_FENCE _ReadWriteBarrier (); MemoryBarrier()
198 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier (); MemoryBarrier() /* according to msdn, _ReadBarrier is not a load fence */
199 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier (); MemoryBarrier()
149 #elif _MSC_VER >= 1400 /* VC++ 2005 */ 200 #elif _MSC_VER >= 1400 /* VC++ 2005 */
150 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier) 201 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
151 #define ECB_MEMORY_FENCE _ReadWriteBarrier () 202 #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
152 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */ 203 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
153 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier () 204 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
173 /* any fence other than seq_cst, which isn't very efficient for us. */ 224 /* any fence other than seq_cst, which isn't very efficient for us. */
174 /* Why that is, we don't know - either the C11 memory model is quite useless */ 225 /* Why that is, we don't know - either the C11 memory model is quite useless */
175 /* for most usages, or gcc and clang have a bug */ 226 /* for most usages, or gcc and clang have a bug */
176 /* I *currently* lean towards the latter, and inefficiently implement */ 227 /* I *currently* lean towards the latter, and inefficiently implement */
177 /* all three of ecb's fences as a seq_cst fence */ 228 /* all three of ecb's fences as a seq_cst fence */
229 /* Update, gcc-4.8 generates mfence for all c++ fences, but nothing */
230 /* for all __atomic_thread_fence's except seq_cst */
178 #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_seq_cst) 231 #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_seq_cst)
179 #endif 232 #endif
180#endif 233#endif
181 234
182#ifndef ECB_MEMORY_FENCE 235#ifndef ECB_MEMORY_FENCE
239 #define ecb_is_constant(expr) __builtin_constant_p (expr) 292 #define ecb_is_constant(expr) __builtin_constant_p (expr)
240 #define ecb_expect(expr,value) __builtin_expect ((expr),(value)) 293 #define ecb_expect(expr,value) __builtin_expect ((expr),(value))
241 #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality) 294 #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
242#else 295#else
243 #define ecb_attribute(attrlist) 296 #define ecb_attribute(attrlist)
297
298 /* possible C11 impl for integral types
299 typedef struct ecb_is_constant_struct ecb_is_constant_struct;
300 #define ecb_is_constant(expr) _Generic ((1 ? (struct ecb_is_constant_struct *)0 : (void *)((expr) - (expr)), ecb_is_constant_struct *: 0, default: 1)) */
301
244 #define ecb_is_constant(expr) 0 302 #define ecb_is_constant(expr) 0
245 #define ecb_expect(expr,value) (expr) 303 #define ecb_expect(expr,value) (expr)
246 #define ecb_prefetch(addr,rw,locality) 304 #define ecb_prefetch(addr,rw,locality)
247#endif 305#endif
248 306
459 ecb_inline void ecb_unreachable (void) ecb_noreturn; 517 ecb_inline void ecb_unreachable (void) ecb_noreturn;
460 ecb_inline void ecb_unreachable (void) { } 518 ecb_inline void ecb_unreachable (void) { }
461#endif 519#endif
462 520
463/* try to tell the compiler that some condition is definitely true */ 521/* try to tell the compiler that some condition is definitely true */
464#define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0) 522#define ecb_assume(cond) if (!(cond)) ecb_unreachable (); else 0
465 523
466ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const; 524ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const;
467ecb_inline unsigned char 525ecb_inline unsigned char
468ecb_byteorder_helper (void) 526ecb_byteorder_helper (void)
469{ 527{
470 const uint32_t u = 0x11223344; 528 /* the union code still generates code under pressure in gcc, */
471 return *(unsigned char *)&u; 529 /* but less than using pointers, and always seems to */
530 /* successfully return a constant. */
531 /* the reason why we have this horrible preprocessor mess */
532 /* is to avoid it in all cases, at least on common architectures */
533 /* or when using a recent enough gcc version (>= 4.6) */
534#if __i386 || __i386__ || _M_X86 || __amd64 || __amd64__ || _M_X64
535 return 0x44;
536#elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
537 return 0x44;
538#elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
539 return 0x11;
540#else
541 union
542 {
543 uint32_t i;
544 uint8_t c;
545 } u = { 0x11223344 };
546 return u.c;
547#endif
472} 548}
473 549
474ecb_inline ecb_bool ecb_big_endian (void) ecb_const; 550ecb_inline ecb_bool ecb_big_endian (void) ecb_const;
475ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; } 551ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
476ecb_inline ecb_bool ecb_little_endian (void) ecb_const; 552ecb_inline ecb_bool ecb_little_endian (void) ecb_const;
507 } 583 }
508#else 584#else
509 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0])) 585 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
510#endif 586#endif
511 587
588/*******************************************************************************/
589/* floating point stuff, can be disabled by defining ECB_NO_LIBM */
590
591/* basically, everything uses "ieee pure-endian" floating point numbers */
592/* the only noteworthy exception is ancient armle, which uses order 43218765 */
593#if 0 \
594 || __i386 || __i386__ \
595 || __amd64 || __amd64__ || __x86_64 || __x86_64__ \
596 || __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ \
597 || defined __arm__ && defined __ARM_EABI__ \
598 || defined __s390__ || defined __s390x__ \
599 || defined __mips__ \
600 || defined __alpha__ \
601 || defined __hppa__ \
602 || defined __ia64__ \
603 || defined __m68k__ \
604 || defined __m88k__ \
605 || defined __sh__ \
606 || defined _M_IX86 || defined _M_AMD64 || defined _M_IA64
607 #define ECB_STDFP 1
608 #include <string.h> /* for memcpy */
609#else
610 #define ECB_STDFP 0
611#endif
612
613#ifndef ECB_NO_LIBM
614
615 #include <math.h> /* for frexp*, ldexp*, INFINITY, NAN */
616
617 /* only the oldest of old doesn't have this one. solaris. */
618 #ifdef INFINITY
619 #define ECB_INFINITY INFINITY
620 #else
621 #define ECB_INFINITY HUGE_VAL
512#endif 622 #endif
513 623
624 #ifdef NAN
625 #define ECB_NAN NAN
626 #else
627 #define ECB_NAN ECB_INFINITY
628 #endif
629
630 /* converts an ieee half/binary16 to a float */
631 ecb_function_ float ecb_binary16_to_float (uint16_t x) ecb_const;
632 ecb_function_ float
633 ecb_binary16_to_float (uint16_t x)
634 {
635 int e = (x >> 10) & 0x1f;
636 int m = x & 0x3ff;
637 float r;
638
639 if (!e ) r = ldexpf (m , -24);
640 else if (e != 31) r = ldexpf (m + 0x400, e - 25);
641 else if (m ) r = ECB_NAN;
642 else r = ECB_INFINITY;
643
644 return x & 0x8000 ? -r : r;
645 }
646
647 /* convert a float to ieee single/binary32 */
648 ecb_function_ uint32_t ecb_float_to_binary32 (float x) ecb_const;
649 ecb_function_ uint32_t
650 ecb_float_to_binary32 (float x)
651 {
652 uint32_t r;
653
654 #if ECB_STDFP
655 memcpy (&r, &x, 4);
656 #else
657 /* slow emulation, works for anything but -0 */
658 uint32_t m;
659 int e;
660
661 if (x == 0e0f ) return 0x00000000U;
662 if (x > +3.40282346638528860e+38f) return 0x7f800000U;
663 if (x < -3.40282346638528860e+38f) return 0xff800000U;
664 if (x != x ) return 0x7fbfffffU;
665
666 m = frexpf (x, &e) * 0x1000000U;
667
668 r = m & 0x80000000U;
669
670 if (r)
671 m = -m;
672
673 if (e <= -126)
674 {
675 m &= 0xffffffU;
676 m >>= (-125 - e);
677 e = -126;
678 }
679
680 r |= (e + 126) << 23;
681 r |= m & 0x7fffffU;
682 #endif
683
684 return r;
685 }
686
687 /* converts an ieee single/binary32 to a float */
688 ecb_function_ float ecb_binary32_to_float (uint32_t x) ecb_const;
689 ecb_function_ float
690 ecb_binary32_to_float (uint32_t x)
691 {
692 float r;
693
694 #if ECB_STDFP
695 memcpy (&r, &x, 4);
696 #else
697 /* emulation, only works for normals and subnormals and +0 */
698 int neg = x >> 31;
699 int e = (x >> 23) & 0xffU;
700
701 x &= 0x7fffffU;
702
703 if (e)
704 x |= 0x800000U;
705 else
706 e = 1;
707
708 /* we distrust ldexpf a bit and do the 2**-24 scaling by an extra multiply */
709 r = ldexpf (x * (0.5f / 0x800000U), e - 126);
710
711 r = neg ? -r : r;
712 #endif
713
714 return r;
715 }
716
717 /* convert a double to ieee double/binary64 */
718 ecb_function_ uint64_t ecb_double_to_binary64 (double x) ecb_const;
719 ecb_function_ uint64_t
720 ecb_double_to_binary64 (double x)
721 {
722 uint64_t r;
723
724 #if ECB_STDFP
725 memcpy (&r, &x, 8);
726 #else
727 /* slow emulation, works for anything but -0 */
728 uint64_t m;
729 int e;
730
731 if (x == 0e0 ) return 0x0000000000000000U;
732 if (x > +1.79769313486231470e+308) return 0x7ff0000000000000U;
733 if (x < -1.79769313486231470e+308) return 0xfff0000000000000U;
734 if (x != x ) return 0X7ff7ffffffffffffU;
735
736 m = frexp (x, &e) * 0x20000000000000U;
737
738 r = m & 0x8000000000000000;;
739
740 if (r)
741 m = -m;
742
743 if (e <= -1022)
744 {
745 m &= 0x1fffffffffffffU;
746 m >>= (-1021 - e);
747 e = -1022;
748 }
749
750 r |= ((uint64_t)(e + 1022)) << 52;
751 r |= m & 0xfffffffffffffU;
752 #endif
753
754 return r;
755 }
756
757 /* converts an ieee double/binary64 to a double */
758 ecb_function_ double ecb_binary64_to_double (uint64_t x) ecb_const;
759 ecb_function_ double
760 ecb_binary64_to_double (uint64_t x)
761 {
762 double r;
763
764 #if ECB_STDFP
765 memcpy (&r, &x, 8);
766 #else
767 /* emulation, only works for normals and subnormals and +0 */
768 int neg = x >> 63;
769 int e = (x >> 52) & 0x7ffU;
770
771 x &= 0xfffffffffffffU;
772
773 if (e)
774 x |= 0x10000000000000U;
775 else
776 e = 1;
777
778 /* we distrust ldexp a bit and do the 2**-53 scaling by an extra multiply */
779 r = ldexp (x * (0.5 / 0x10000000000000U), e - 1022);
780
781 r = neg ? -r : r;
782 #endif
783
784 return r;
785 }
786
787#endif
788
789#endif
790

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