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Comparing libeio/ecb.h (file contents):
Revision 1.3 by root, Mon Jun 20 07:28:14 2011 UTC vs.
Revision 1.8 by root, Sun Aug 21 01:03:09 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
… …
61 #else 61 #else
62 #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor))) 62 #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
63 #endif 63 #endif
64#endif 64#endif
65 65
66/*****************************************************************************/
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
75#ifndef ECB_MEMORY_FENCE
76 #if ECB_GCC_VERSION(2,5)
77 #if __x86
78 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory")
79 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE /* non-lock xchg might be enough */
80 #define ECB_MEMORY_FENCE_RELEASE do { } while (0) /* unlikely to change in future cpus */
81 #elif __amd64
82 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "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__
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")
93 #endif
94 #endif
95#endif
96
97#ifndef ECB_MEMORY_FENCE
98 #if ECB_GCC_VERSION(4,4) || defined(__INTEL_COMPILER)
99 #define ECB_MEMORY_FENCE __sync_synchronize ()
100 /*#define ECB_MEMORY_FENCE_ACQUIRE ({ char dummy = 0; __sync_lock_test_and_set (&dummy, 1); }) */
101 /*#define ECB_MEMORY_FENCE_RELEASE ({ char dummy = 1; __sync_lock_release (&dummy ); }) */
102 #elif _MSC_VER >= 1400 /* VC++ 2005 */
103 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
104 #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
105 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
106 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
107 #elif defined(_WIN32)
108 #include <WinNT.h>
109 #define ECB_MEMORY_FENCE MemoryBarrier () /* actually just xchg on x86... scary */
110 #endif
111#endif
112
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 */
122 #include <pthread.h>
123 #define ECB_NEEDS_PTHREADS 1
124 #define ECB_MEMORY_FENCE_NEEDS_PTHREADS 1
125
126 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
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)
132 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
133#endif
134
135#if !defined(ECB_MEMORY_FENCE_RELEASE) && defined(ECB_MEMORY_FENCE)
136 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
137#endif
138
139/*****************************************************************************/
140
66#define ECB_C99 (__STDC_VERSION__ >= 199901L) 141#define ECB_C99 (__STDC_VERSION__ >= 199901L)
67 142
68#if __cplusplus 143#if __cplusplus
69 #define ecb_inline static inline 144 #define ecb_inline static inline
70#elif ECB_GCC_VERSION(2,5) 145#elif ECB_GCC_VERSION(2,5)
… …
189 x *= 0x01010101; 264 x *= 0x01010101;
190 265
191 return x >> 24; 266 return x >> 24;
192 } 267 }
193 268
194 /* you have the choice beetween something with a table lookup, */
195 /* something using lots of bit arithmetic and a simple loop */
196 /* we went for the loop */
197 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const; 269 ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
198 ecb_function_ int ecb_ld32 (uint32_t x) 270 ecb_function_ int ecb_ld32 (uint32_t x)
199 { 271 {
200 int r = 0; 272 int r = 0;
201 273

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