FORCE_INLINE U64 XXH64_digest_endian()

in lz4/xxhash.c [842:921]

• 68 lines of code
• 5 McCabe index (conditional complexity)

FORCE_INLINE U64 XXH64_digest_endian (const XXH64_state_t* state_in, XXH_endianess endian)
{
    XXH_istate64_t * state = (XXH_istate64_t *) state_in;
    const BYTE * p = (const BYTE*)state->mem64;
    BYTE* bEnd = (BYTE*)state->mem64 + state->memsize;
    U64 h64;

    if (state->total_len >= 32)
    {
        U64 v1 = state->v1;
        U64 v2 = state->v2;
        U64 v3 = state->v3;
        U64 v4 = state->v4;

        h64 = XXH_rotl64(v1, 1) + XXH_rotl64(v2, 7) + XXH_rotl64(v3, 12) + XXH_rotl64(v4, 18);

        v1 *= PRIME64_2;
        v1 = XXH_rotl64(v1, 31);
        v1 *= PRIME64_1;
        h64 ^= v1;
        h64 = h64*PRIME64_1 + PRIME64_4;

        v2 *= PRIME64_2;
        v2 = XXH_rotl64(v2, 31);
        v2 *= PRIME64_1;
        h64 ^= v2;
        h64 = h64*PRIME64_1 + PRIME64_4;

        v3 *= PRIME64_2;
        v3 = XXH_rotl64(v3, 31);
        v3 *= PRIME64_1;
        h64 ^= v3;
        h64 = h64*PRIME64_1 + PRIME64_4;

        v4 *= PRIME64_2;
        v4 = XXH_rotl64(v4, 31);
        v4 *= PRIME64_1;
        h64 ^= v4;
        h64 = h64*PRIME64_1 + PRIME64_4;
    }
    else
    {
        h64  = state->seed + PRIME64_5;
    }

    h64 += (U64) state->total_len;

    while (p+8<=bEnd)
    {
        U64 k1 = XXH_readLE64(p, endian);
        k1 *= PRIME64_2;
        k1 = XXH_rotl64(k1,31);
        k1 *= PRIME64_1;
        h64 ^= k1;
        h64 = XXH_rotl64(h64,27) * PRIME64_1 + PRIME64_4;
        p+=8;
    }

    if (p+4<=bEnd)
    {
        h64 ^= (U64)(XXH_readLE32(p, endian)) * PRIME64_1;
        h64 = XXH_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
        p+=4;
    }

    while (p<bEnd)
    {
        h64 ^= (*p) * PRIME64_5;
        h64 = XXH_rotl64(h64, 11) * PRIME64_1;
        p++;
    }

    h64 ^= h64 >> 33;
    h64 *= PRIME64_2;
    h64 ^= h64 >> 29;
    h64 *= PRIME64_3;
    h64 ^= h64 >> 32;

    return h64;
}