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Comparing libeio/ecb.h (file contents):
Revision 1.6 by root, Tue Jul 26 11:07:08 2011 UTC vs.
Revision 1.9 by root, Thu Sep 15 13:20:54 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#endif
74
68#ifndef ECB_MEMORY_FENCE 75#ifndef ECB_MEMORY_FENCE
69 #if ECB_GCC_VERSION(2,5) 76 #if ECB_GCC_VERSION(2,5)
70 #if __x86 77 #if __i386__
71 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory") 78 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory")
72 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE 79 #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 */ 80 #define ECB_MEMORY_FENCE_RELEASE do { } while (0) /* unlikely to change in future cpus */
74 #elif __amd64 81 #elif __amd64
75 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory") 82 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory")
76 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("lfence" : : : "memory") 83 #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("lfence" : : : "memory")
84 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("sfence") /* play safe - not needed in any current cpu */
85 #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__
77 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("sfence") 86 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
87 #elif defined(__ARM_ARCH_6__ ) || defined(__ARM_ARCH_6J__ ) \
88 || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6ZK__)
89 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory")
90 #elif defined(__ARM_ARCH_7__ ) || defined(__ARM_ARCH_7A__ ) \
91 || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7R__ )
92 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory")
78 #endif 93 #endif
79 #endif 94 #endif
80#endif 95#endif
81 96
82#ifndef ECB_MEMORY_FENCE 97#ifndef ECB_MEMORY_FENCE
83 #if ECB_GCC_VERSION(4,4) 98 #if ECB_GCC_VERSION(4,4) || defined(__INTEL_COMPILER)
84 #define ECB_MEMORY_FENCE __sync_synchronize () 99 #define ECB_MEMORY_FENCE __sync_synchronize ()
85 #define ECB_MEMORY_FENCE_ACQUIRE ({ char dummy = 0; __sync_lock_test_and_set (&dummy, 1); }) 100 /*#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 ); }) 101 /*#define ECB_MEMORY_FENCE_RELEASE ({ char dummy = 1; __sync_lock_release (&dummy ); }) */
87 #elif _MSC_VER >= 1400 && 0 /* TODO: only true when using volatiles */ 102 #elif _MSC_VER >= 1400 /* VC++ 2005 */
103 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
88 #define ECB_MEMORY_FENCE do { } while (0) 104 #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
89 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE 105 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
90 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE 106 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
91 #elif defined(_WIN32) 107 #elif defined(_WIN32)
92 #include <WinNT.h> 108 #include <WinNT.h>
93 #define ECB_MEMORY_FENCE MemoryBarrier () 109 #define ECB_MEMORY_FENCE MemoryBarrier () /* actually just xchg on x86... scary */
94 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
95 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
96 #endif 110 #endif
97#endif 111#endif
98 112
99#ifndef ECB_MEMORY_FENCE 113#ifndef ECB_MEMORY_FENCE
114 #if !ECB_AVOID_PTHREADS
115 /*
116 * if you get undefined symbol references to pthread_mutex_lock,
117 * or failure to find pthread.h, then you should implement
118 * the ECB_MEMORY_FENCE operations for your cpu/compiler
119 * OR provide pthread.h and link against the posix thread library
120 * of your system.
121 */
100 #include <pthread.h> 122 #include <pthread.h>
123 #define ECB_NEEDS_PTHREADS 1
124 #define ECB_MEMORY_FENCE_NEEDS_PTHREADS 1
101 125
102 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER; 126 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) 127 #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0)
128 #endif
129#endif
130
131#if !defined(ECB_MEMORY_FENCE_ACQUIRE) && defined(ECB_MEMORY_FENCE)
104 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE 132 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
133#endif
134
135#if !defined(ECB_MEMORY_FENCE_RELEASE) && defined(ECB_MEMORY_FENCE)
105 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE 136 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
106#endif 137#endif
107 138
108/*****************************************************************************/ 139/*****************************************************************************/
109 140
… …
233 x *= 0x01010101; 264 x *= 0x01010101;
234 265
235 return x >> 24; 266 return x >> 24;
236 } 267 }
237 268
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; 269 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
242 ecb_function_ int ecb_ld32 (uint32_t x) 270 ecb_function_ int ecb_ld32 (uint32_t x)
243 { 271 {
244 int r = 0; 272 int r = 0;
245 273

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