bird/lib/bitops.h
2015-06-08 02:24:08 +02:00

29 lines
614 B
C

/*
* BIRD Library -- Generic Bit Operations
*
* (c) 1998 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#ifndef _BIRD_BITOPTS_H_
#define _BIRD_BITOPTS_H_
/*
* Bit mask operations:
*
* u32_mkmask Make bit mask consisting of <n> consecutive ones
* from the left and the rest filled with zeroes.
* E.g., u32_mkmask(5) = 0xf8000000.
* u32_masklen Inverse operation to u32_mkmask, -1 if not a bitmask.
*/
u32 u32_mkmask(uint n);
int u32_masklen(u32 x);
u32 u32_log2(u32 v);
static inline u32 u32_hash(u32 v) { return v * 2902958171u; }
#endif