#ifndef CRC32_BRAID_COMB_P_H_

#define CRC32_BRAID_COMB_P_H_

/*

  Return a(x) multiplied by b(x) modulo p(x), where p(x) is the CRC polynomial,

  reflected. For speed, this requires that a not be zero.

 */

static uint32_t multmodp(uint32_t a, uint32_t b) {

    uint32_t m, p;

    m = (uint32_t)1 << 31;

    p = 0;

    for (;;) {

        if (a & m) {

            p ^= b;

            if ((a & (m - 1)) == 0)

                break;

        }

        m >>= 1;

        b = b & 1 ? (b >> 1) ^ POLY : b >> 1;

    }

    return p;

}

/*

  Return x^(n * 2^k) modulo p(x). Requires that x2n_table[] has been

  initialized.

 */

static uint32_t x2nmodp(z_off64_t n, unsigned k) {

    uint32_t p;

    p = (uint32_t)1 << 31;           /* x^0 == 1 */

    while (n) {

        if (n & 1)

            p = multmodp(x2n_table[k & 31], p);

        n >>= 1;

        k++;

    }

    return p;

}

#endif /* CRC32_BRAID_COMB_P_H_ */