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Comparing libecb/ecb.h (file contents):
Revision 1.91 by root, Tue May 29 14:30:44 2012 UTC vs.
Revision 1.98 by root, Thu Jun 7 21:25:13 2012 UTC

… …
83 83
84#define ECB_C (__STDC__+0) /* this assumes that __STDC__ is either empty or a number */ 84#define ECB_C (__STDC__+0) /* this assumes that __STDC__ is either empty or a number */
85#define ECB_C99 (__STDC_VERSION__ >= 199901L) 85#define ECB_C99 (__STDC_VERSION__ >= 199901L)
86#define ECB_C11 (__STDC_VERSION__ >= 201112L) 86#define ECB_C11 (__STDC_VERSION__ >= 201112L)
87#define ECB_CPP (__cplusplus+0) 87#define ECB_CPP (__cplusplus+0)
88#define ECB_CPP98 (__cplusplus >= 199711L)
89#define ECB_CPP11 (__cplusplus >= 201103L) 88#define ECB_CPP11 (__cplusplus >= 201103L)
90 89
91/*****************************************************************************/ 90/*****************************************************************************/
92 91
93/* ECB_NO_THREADS - ecb is not used by multiple threads, ever */ 92/* ECB_NO_THREADS - ecb is not used by multiple threads, ever */
94/* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */ 93/* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */
95 94
96#if ECB_NO_THREADS 95#if ECB_NO_THREADS
97# define ECB_NO_SMP 1 96 #define ECB_NO_SMP 1
98#endif 97#endif
99 98
100#if ECB_NO_THREADS || ECB_NO_SMP 99#if ECB_NO_SMP
101 #define ECB_MEMORY_FENCE do { } while (0) 100 #define ECB_MEMORY_FENCE do { } while (0)
102#endif
103
104#ifndef ECB_MEMORY_FENCE
105 #if ECB_C11 && !defined __STDC_NO_ATOMICS__
106 /* we assume that these memory fences work on all variables/all memory accesses, */
107 /* not just C11 atomics and atomic accesses */
108 #include <stdatomic.h>
109 #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_acq_rel)
110 #define ECB_MEMORY_FENCE_ACQUIRE atomic_thread_fence (memory_order_acquire)
111 #define ECB_MEMORY_FENCE_RELEASE atomic_thread_fence (memory_order_release)
112 #endif
113#endif 101#endif
114 102
115#ifndef ECB_MEMORY_FENCE 103#ifndef ECB_MEMORY_FENCE
116 #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110 104 #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
117 #if __i386 || __i386__ 105 #if __i386 || __i386__
118 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory") 106 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory")
119 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE /* non-lock xchg might be enough */ 107 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
120 #define ECB_MEMORY_FENCE_RELEASE do { } while (0) /* unlikely to change in future cpus */ 108 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
121 #elif __amd64 || __amd64__ || __x86_64 || __x86_64__ 109 #elif __amd64 || __amd64__ || __x86_64 || __x86_64__
122 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory") 110 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory")
123 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("lfence" : : : "memory") 111 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory")
124 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("sfence") /* play safe - not needed in any current cpu */ 112 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
125 #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ 113 #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__
126 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory") 114 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
127 #elif defined __ARM_ARCH_6__ || defined __ARM_ARCH_6J__ \ 115 #elif defined __ARM_ARCH_6__ || defined __ARM_ARCH_6J__ \
128 || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__ 116 || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__
129 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory") 117 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory")
130 #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \ 118 #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \
131 || defined __ARM_ARCH_7M__ || defined __ARM_ARCH_7R__ 119 || defined __ARM_ARCH_7M__ || defined __ARM_ARCH_7R__
132 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory") 120 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory")
133 #elif __sparc || __sparc__ 121 #elif __sparc || __sparc__
134 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad | " : : : "memory") 122 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad" : : : "memory")
135 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory") 123 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory")
136 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore") 124 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore")
137 #elif defined __s390__ || defined __s390x__ 125 #elif defined __s390__ || defined __s390x__
138 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory") 126 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory")
139 #elif defined __mips__ 127 #elif defined __mips__
140 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory") 128 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
141 #elif defined __alpha__ 129 #elif defined __alpha__
142 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mb" : : : "memory") 130 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mb" : : : "memory")
131 #elif defined __hppa__
132 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory")
133 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("")
134 #elif defined __ia64__
135 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mf" : : : "memory")
143 #endif 136 #endif
144 #endif 137 #endif
145#endif 138#endif
146 139
147#ifndef ECB_MEMORY_FENCE 140#ifndef ECB_MEMORY_FENCE
141 #if ECB_GCC_VERSION(4,7)
142 /* see comment below (stdatomic.h) about the C11 memory model. */
143 #define ECB_MEMORY_FENCE __atomic_thread_fence (__ATOMIC_SEQ_CST)
144 #elif defined __clang && __has_feature (cxx_atomic)
145 /* see comment below (stdatomic.h) about the C11 memory model. */
146 #define ECB_MEMORY_FENCE __c11_atomic_thread_fence (__ATOMIC_SEQ_CST)
148 #if ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__ 147 #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__
149 #define ECB_MEMORY_FENCE __sync_synchronize () 148 #define ECB_MEMORY_FENCE __sync_synchronize ()
150 /*#define ECB_MEMORY_FENCE_ACQUIRE ({ char dummy = 0; __sync_lock_test_and_set (&dummy, 1); }) */
151 /*#define ECB_MEMORY_FENCE_RELEASE ({ char dummy = 1; __sync_lock_release (&dummy ); }) */
152 #elif _MSC_VER >= 1400 /* VC++ 2005 */ 149 #elif _MSC_VER >= 1400 /* VC++ 2005 */
153 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier) 150 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
154 #define ECB_MEMORY_FENCE _ReadWriteBarrier () 151 #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
155 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */ 152 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
156 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier () 153 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
… …
166 #define ECB_MEMORY_FENCE __sync () 163 #define ECB_MEMORY_FENCE __sync ()
167 #endif 164 #endif
168#endif 165#endif
169 166
170#ifndef ECB_MEMORY_FENCE 167#ifndef ECB_MEMORY_FENCE
168 #if ECB_C11 && !defined __STDC_NO_ATOMICS__
169 /* we assume that these memory fences work on all variables/all memory accesses, */
170 /* not just C11 atomics and atomic accesses */
171 #include <stdatomic.h>
172 /* Unfortunately, neither gcc 4.7 nor clang 3.1 generate any instructions for */
173 /* 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 */
175 /* for most usages, or gcc and clang have a bug */
176 /* I *currently* lean towards the latter, and inefficiently implement */
177 /* all three of ecb's fences as a seq_cst fence */
178 #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_seq_cst)
179 #endif
180#endif
181
182#ifndef ECB_MEMORY_FENCE
171 #if !ECB_AVOID_PTHREADS 183 #if !ECB_AVOID_PTHREADS
172 /* 184 /*
173 * if you get undefined symbol references to pthread_mutex_lock, 185 * if you get undefined symbol references to pthread_mutex_lock,
174 * or failure to find pthread.h, then you should implement 186 * or failure to find pthread.h, then you should implement
175 * the ECB_MEMORY_FENCE operations for your cpu/compiler 187 * the ECB_MEMORY_FENCE operations for your cpu/compiler
… …
453 465
454ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const; 466ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const;
455ecb_inline unsigned char 467ecb_inline unsigned char
456ecb_byteorder_helper (void) 468ecb_byteorder_helper (void)
457{ 469{
458 const uint32_t u = 0x11223344; 470 /* the union code still generates code under pressure in gcc, */
459 return *(unsigned char *)&u; 471 /* but less than using pointers, and always seem to */
472 /* successfully return a constant. */
473 /* the reason why we have this horrible preprocessor mess */
474 /* is to avoid it in all cases, at leats on common architectures */
475#if __i386 || __i386__ || _M_X86 || __amd64 || __amd64__ || _M_X64
476 return 0x44;
477#elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
478 return 0x44;
479#elif __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
480 retrurn 0x11;
481#else
482 union
483 {
484 uint32_t i;
485 uint8_t c;
486 } u = { 0x11223344 };
487 return u.c;
488#endif
460} 489}
461 490
462ecb_inline ecb_bool ecb_big_endian (void) ecb_const; 491ecb_inline ecb_bool ecb_big_endian (void) ecb_const;
463ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; } 492ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
464ecb_inline ecb_bool ecb_little_endian (void) ecb_const; 493ecb_inline ecb_bool ecb_little_endian (void) ecb_const;

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