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Comparing libecb/ecb.h (file contents):
Revision 1.54 by root, Wed Jul 20 00:38:30 2011 UTC vs.
Revision 1.59 by sf-exg, Thu Aug 4 06:38:35 2011 UTC

… …
48 #include <inttypes.h> 48 #include <inttypes.h>
49#endif 49#endif
50 50
51/* many compilers define _GNUC_ to some versions but then only implement 51/* many compilers define _GNUC_ to some versions but then only implement
52 * what their idiot authors think are the "more important" extensions, 52 * what their idiot authors think are the "more important" extensions,
53 * causing enourmous grief in return for some better fake benchmark numbers. 53 * causing enormous grief in return for some better fake benchmark numbers.
54 * or so. 54 * or so.
55 * we try to detect these and simply assume they are not gcc - if they have 55 * we try to detect these and simply assume they are not gcc - if they have
56 * an issue with that they should have done it right in the first place. 56 * an issue with that they should have done it right in the first place.
57 */ 57 */
58#ifndef ECB_GCC_VERSION 58#ifndef ECB_GCC_VERSION
… …
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 96 #elif _MSC_VER >= 1400 /* VC++ 2005 */
88 #define ECB_MEMORY_FENCE do { } while (0) 97 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
89 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
90 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
91 #elif defined(_WIN32) && defined(MemoryBarrier)
92 #define ECB_MEMORY_FENCE MemoryBarrier () 98 #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
99 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
100 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
101 #elif defined(_WIN32)
102 #include <WinNT.h>
103 #define ECB_MEMORY_FENCE MemoryBarrier () /* actually just xchg on x86... scary */
93 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE 104 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
94 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE 105 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
95 #endif 106 #endif
96#endif 107#endif
97 108
98#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 provide pthread.h and link against the posix thread library
115 * of your system.
116 */
99 #include <pthread.h> 117 #include <pthread.h>
100 118
101 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER; 119 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
102 #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)
103 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE 121 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
… …
232 x *= 0x01010101; 250 x *= 0x01010101;
233 251
234 return x >> 24; 252 return x >> 24;
235 } 253 }
236 254
237 /* you have the choice beetween something with a table lookup, */
238 /* something using lots of bit arithmetic and a simple loop */
239 /* we went for the loop */
240 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const; 255 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
241 ecb_function_ int ecb_ld32 (uint32_t x) 256 ecb_function_ int ecb_ld32 (uint32_t x)
242 { 257 {
243 int r = 0; 258 int r = 0;
244 259

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