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/*
* 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_
#include "sysdep/config.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);
uint u32_masklen(u32 x);
u32 u32_log2(u32 v);
static inline u32 u32_hash(u32 v) { return v * 2902958171u; }
static inline u8 u32_popcount(u32 v) { return __builtin_popcount(v); }
static inline u8 u64_popcount(u64 v) { return __builtin_popcountll(v); }
static inline int u32_clz(u32 v) { return __builtin_clz(v); }
static inline int u32_ctz(u32 v) { return __builtin_ctz(v); }
static inline int uint_is_pow2(uint n) { return n && !(n & (n-1)); }
#endif
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