Bit Manipulation

include/math/bit.h View source View on GitHub

Macros

BIT

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

BIT_SET

#define BIT_SET(val, n) ((val) | BIT(n))

BIT_CLEAR

#define BIT_CLEAR(val, n) ((val) & ~BIT(n))

BIT_TEST

#define BIT_TEST(val, n) (((val) >> (n)) & 1ull)

BIT_TOGGLE

#define BIT_TOGGLE(val, n) ((val) ^ BIT(n))

BIT_MASK

#define BIT_MASK(lo, hi) ((~0ULL >> (64ULL - 1ULL - ((hi) - (lo)))) << (lo))

BIT_RANGE

#define BIT_RANGE(val, lo, hi) \
    (((val) >> (lo)) & (~0ULL >> (64ULL - 1ULL - ((hi) - (lo)))))

BIT_GET_FIELD

#define BIT_GET_FIELD(val, lo, hi) \
    ({ \
        uint64_t __v = (uint64_t) (val); \
        uint32_t __l = (uint32_t) (lo); \
        uint32_t __h = (uint32_t) (hi); \
        (void) kassert(__l <= __h && __h < 64); \
        ((__v >> __l) & (~0ULL >> (64ULL - 1ULL - (__h - __l)))); \
    })

BIT_SET_FIELD

#define BIT_SET_FIELD(val, field_val, lo, hi) \
    ({ \
        uint64_t __v = (uint64_t) (val); \
        uint64_t __fv = (uint64_t) (field_val); \
        uint32_t __l = (uint32_t) (lo); \
        uint32_t __h = (uint32_t) (hi); \
        (void) kassert(__l <= __h && __h < 64); \
        uint64_t __mask = (~0ULL >> (64ULL - 1ULL - (__h - __l))) << __l; \
        ((__v & ~__mask) | ((__fv << __l) & __mask)); \
    })

SET_FIELD

#define SET_FIELD(val, field_val, lo, hi) BIT_SET_FIELD(val, field_val, lo, hi)

BIT_ANY

#define BIT_ANY(val, mask) (((val) & (mask)) != 0)

BIT_ALL

#define BIT_ALL(val, mask) (((val) & (mask)) == (mask))

BIT_WIDTH

#define BIT_WIDTH(lo, hi) \
    ({ \
        uint32_t __l = (uint32_t) (lo); \
        uint32_t __h = (uint32_t) (hi); \
        (void) kassert(__l <= __h); \
        ((__h - __l) + 1u); \
    })

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