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Annotation of embedaddon/bird/lib/bitops.h, revision 1.1.1.1

1.1       misho       1: /*
                      2:  *     BIRD Library -- Generic Bit Operations
                      3:  *
                      4:  *     (c) 1998 Martin Mares <mj@ucw.cz>
                      5:  *
                      6:  *     Can be freely distributed and used under the terms of the GNU GPL.
                      7:  */
                      8: 
                      9: #ifndef _BIRD_BITOPTS_H_
                     10: #define _BIRD_BITOPTS_H_
                     11: 
                     12: /*
                     13:  *     Bit mask operations:
                     14:  *
                     15:  *     u32_mkmask      Make bit mask consisting of <n> consecutive ones
                     16:  *                     from the left and the rest filled with zeroes.
                     17:  *                     E.g., u32_mkmask(5) = 0xf8000000.
                     18:  *     u32_masklen     Inverse operation to u32_mkmask, -1 if not a bitmask.
                     19:  */
                     20: 
                     21: u32 u32_mkmask(uint n);
                     22: int u32_masklen(u32 x);
                     23: 
                     24: u32 u32_log2(u32 v);
                     25: 
                     26: static inline u32 u32_hash(u32 v) { return v * 2902958171u; }
                     27: 
                     28: static inline u8 u32_popcount(u32 v) { return __builtin_popcount(v); }
                     29: 
                     30: #endif