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Comparing libecb/ecb.h (file contents):
Revision 1.55 by root, Tue Jul 26 09:59:36 2011 UTC vs.
Revision 1.58 by root, Wed Aug 3 15:40:18 2011 UTC

… …
63 #endif 63 #endif
64#endif 64#endif
65 65
66/*****************************************************************************/ 66/*****************************************************************************/
67 67
68/* 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 */
70
71#if ECB_NO_THREADS || ECB_NO_SMP
72 #define ECB_MEMORY_FENCE do { } while (0)
73 #define ECB_MEMORY_FENCE_ACQUIRE do { } while (0)
74 #define ECB_MEMORY_FENCE_RELEASE do { } while (0)
75#endif
76
68#ifndef ECB_MEMORY_FENCE 77#ifndef ECB_MEMORY_FENCE
69 #if ECB_GCC_VERSION(2,5) 78 #if ECB_GCC_VERSION(2,5)
70 #if __x86 79 #if __x86
71 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory") 80 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory")
72 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE 81 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE /* non-lock xchg might be enough */
73 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE /* better be safe than sorry */ 82 #define ECB_MEMORY_FENCE_RELEASE do { } while (0) /* unlikely to change in future cpus */
74 #elif __amd64 83 #elif __amd64
75 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory") 84 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory")
76 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("lfence" : : : "memory") 85 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("lfence" : : : "memory")
77 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("sfence") 86 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("sfence") /* play safe - not needed in any current cpu */
78 #endif 87 #endif
79 #endif 88 #endif
80#endif 89#endif
81 90
82#ifndef ECB_MEMORY_FENCE 91#ifndef ECB_MEMORY_FENCE
83 #if ECB_GCC_VERSION(4,4) 92 #if ECB_GCC_VERSION(4,4)
84 #define ECB_MEMORY_FENCE __sync_synchronize () 93 #define ECB_MEMORY_FENCE __sync_synchronize ()
85 #define ECB_MEMORY_FENCE_ACQUIRE ({ char dummy = 0; __sync_lock_test_and_set (&dummy, 1); }) 94 #define ECB_MEMORY_FENCE_ACQUIRE ({ char dummy = 0; __sync_lock_test_and_set (&dummy, 1); })
86 #define ECB_MEMORY_FENCE_RELEASE ({ char dummy = 1; __sync_lock_release (&dummy ); }) 95 #define ECB_MEMORY_FENCE_RELEASE ({ char dummy = 1; __sync_lock_release (&dummy ); })
87 #elif _MSC_VER >= 1400 && 0 /* TODO: only true when using volatiles */ 96 #elif _MSC_VER >= 1400 /* VC++ 2005 */
97 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
88 #define ECB_MEMORY_FENCE do { } while (0) 98 #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
89 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE 99 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
90 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE 100 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
91 #elif defined(_WIN32) 101 #elif defined(_WIN32)
92 #include <WinNT.h> 102 #include <WinNT.h>
93 #define ECB_MEMORY_FENCE MemoryBarrier () 103 #define ECB_MEMORY_FENCE MemoryBarrier () /* actually just xchg on x86... scary */
94 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE 104 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
95 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE 105 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
96 #endif 106 #endif
97#endif 107#endif
98 108
99#ifndef ECB_MEMORY_FENCE 109#ifndef ECB_MEMORY_FENCE
110 /*
111 * if you get undefined symbol references to pthread_mutex_lock,
112 * or failure to find pthread.h, then you should implement
113 * the ECB_MEMORY_FENCE operations for your cpu/compiler
114 * OR proide pthread.h and link against the posix thread library
115 * of your system.
116 */
100 #include <pthread.h> 117 #include <pthread.h>
101 118
102 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER; 119 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
103 #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0) 120 #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0)
104 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE 121 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
… …
233 x *= 0x01010101; 250 x *= 0x01010101;
234 251
235 return x >> 24; 252 return x >> 24;
236 } 253 }
237 254
238 /* you have the choice beetween something with a table lookup, */
239 /* something using lots of bit arithmetic and a simple loop */
240 /* we went for the loop */
241 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const; 255 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
242 ecb_function_ int ecb_ld32 (uint32_t x) 256 ecb_function_ int ecb_ld32 (uint32_t x)
243 { 257 {
244 int r = 0; 258 int r = 0;
245 259

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