xref: /isa-l_crypto/rolling_hash/rolling_hashx_base.c (revision 81c7feeeb9cf25d8080286d86bc1e13ecc129c7a)

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  modification, are permitted provided that the following conditions
  are met:
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      contributors may be used to endorse or promote products derived
      from this software without specific prior written permission.

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#include <stdint.h>
#ifdef _MSC_VER
#define inline __inline
#endif

static inline int
floor_pow2(uint32_t in)
{
        uint32_t x = in;

        while (in) {
                x = in;
                in &= (in - 1);
        }
        return x;
}

static inline uint32_t
rol(uint32_t x, int i)
{
        return x << i | x >> (8 * sizeof(x) - i);
}

uint32_t
_rolling_hashx_mask_gen(long mean, int shift)
{
        if (mean <= 2)
                mean = 2;

        return rol(floor_pow2(mean) - 1, shift);
}

struct slver {
        uint16_t snum;
        uint8_t ver;
        uint8_t core;
};
struct slver _rolling_hashx_mask_gen_slver_00000260;
struct slver _rolling_hashx_mask_gen_slver = { 0x0260, 0x00, 0x00 };