kernel/include/util/bits.h


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#pragma once

#include "kernel.h"
#include "types.h"

#define BIT(n) (1 << (n))

static inline void bit_flip(void *addr, uintptr_t bit)
{
    uint32_t *map = (uint32_t *)addr;
    map += (bit >> 5);
    *map ^= (uint32_t)(1 << (bit & 0x1f));
}

static inline int bit_check(const void *addr, uintptr_t bit)
{
    const uint32_t *map = (const uint32_t *)addr;
    map += (bit >> 5);
    return (*map & (1 << (bit & 0x1f)));
}

#define MOD_POW_2(x, y) ((x) & ((y)-1))

#define IS_POW_2(x) (!MOD_POW_2(x, x))

#define SELECT(condition, trueval, falseval) \
    (!!(condition) * (trueval) + !condition * (falseval))