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Comparing libecb/ecb.h (file contents):
Revision 1.5 by root, Thu May 26 17:27:15 2011 UTC vs.
Revision 1.6 by root, Thu May 26 17:35:47 2011 UTC

… …
26 * OF THE POSSIBILITY OF SUCH DAMAGE. 26 * OF THE POSSIBILITY OF SUCH DAMAGE.
27 */ 27 */
28 28
29#ifndef ECB_H 29#ifndef ECB_H
30#define ECB_H 30#define ECB_H
31
32#include <inttypes.h>
31 33
32#define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor))) 34#define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
33 35
34#ifndef __cplusplus 36#ifndef __cplusplus
35# if __STDC_VERSION__ >= 199901L 37# if __STDC_VERSION__ >= 199901L
… …
79#endif 81#endif
80 82
81/* put into ifs if you are very sure that the expression */ 83/* put into ifs if you are very sure that the expression */
82/* is mostly true or mosty false. note that these return */ 84/* is mostly true or mosty false. note that these return */
83/* booleans, not the expression. */ 85/* booleans, not the expression. */
84#define ecb_expect_false(expr) ecb_expect ((expr) ? 1 : 0, 0) 86#define ecb_unlikely(expr) ecb_expect ((expr) ? 1 : 0, 0)
85#define ecb_expect_true(expr) ecb_expect ((expr) ? 1 : 0, 1) 87#define ecb_likely(expr) ecb_expect ((expr) ? 1 : 0, 1)
86 88
87/* try to tell the compiler that some condition is definitely true */ 89/* try to tell the compiler that some condition is definitely true */
88#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0) 90#define ecb_assume(cond) do { if (!(cond)) unreachable (); } while (0)
89 91
90/* count trailing zero bits and count # of one bits */ 92/* count trailing zero bits and count # of one bits */
91#if ECB_GCC_VERSION(3,4) 93#if ECB_GCC_VERSION(3,4)
92ECB_HEADER_INLINE int ecb_ctz32 (unsigned int x) { return __builtin_ctz (x); } 94ECB_HEADER_INLINE int ecb_ctz32 (uint32_t x) { return __builtin_ctz (x); }
93ECB_HEADER_INLINE int ecb_popcount32 (unsigned int x) { return __builtin_popcount (x); } 95ECB_HEADER_INLINE int ecb_popcount32 (uint32_t x) { return __builtin_popcount (x); }
94#else 96#else
95ECB_HEADER_INLINE 97ECB_HEADER_INLINE
96ecb_ctz32 (unsigned int x) ecb_const 98ecb_ctz32 (uint32_t x) ecb_const
97{ 99{
98 int r = 0; 100 int r = 0;
99 101
100 x &= -x; /* this isolates the lowest bit */ 102 x &= -x; /* this isolates the lowest bit */
101 103
… …
107 109
108 return r; 110 return r;
109} 111}
110 112
111ECB_HEADER_INLINE 113ECB_HEADER_INLINE
112ecb_popcount32 (unsigned int x) ecb_const 114ecb_popcount32 (uint32_t x) ecb_const
113{ 115{
114 x -= (x >> 1) & 0x55555555; 116 x -= (x >> 1) & 0x55555555;
115 x = ((x >> 2) & 0x33333333) + (x & 0x33333333); 117 x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
116 x = ((x >> 4) + x) & 0x0f0f0f0f; 118 x = ((x >> 4) + x) & 0x0f0f0f0f;
117 x *= 0x01010101; 119 x *= 0x01010101;
… …
139} 141}
140#else 142#else
141#define ecb_array_length(name) (sizeof (name) / sizeof (name [0])) 143#define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
142#endif 144#endif
143 145
146ECB_INLINE uint32_t
147ecb_rotate32_right (uint32_t c, unsigned int count = 1)
148{
149 return (c << (32 - count)) | (c >> count);
150}
151
152ECB_INLINE uint32_t
153ecb_rotate32_left (uint32_t c, unsigned int count = 1)
154{
155 return (c >> (32 - count)) | (c << count);
156}
157
144#endif 158#endif
145 159

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