Function MurmurHash32

util/digest/murmur.cpp:20–60

    //    machines.

    Y_NO_INLINE ui32 MurmurHash32(const void* key, size_t len, ui32 seed) noexcept {
        const ui32 m = 0x5bd1e995;
        const int r = 24;
        ui32 h = ui32(seed ^ len);

        TUnalignedMemoryIterator<ui32> iter(key, len);

        while (!iter.AtEnd()) {
            ui32 k = iter.Next();

            k *= m;
            k ^= k >> r;
            k *= m;

            h *= m;
            h ^= k;
        }

        const unsigned char* data = iter.Last();

        switch (iter.Left()) {
            case 3:
                h ^= data[2] << 16;
                [[fallthrough]];

            case 2:
                h ^= data[1] << 8;
                [[fallthrough]];

            case 1:
                h ^= data[0];
                h *= m;
                break;
        }

        h ^= h >> 13;
        h *= m;
        h ^= h >> 15;

        return h;
    }

    //-----------------------------------------------------------------------------
    // MurmurHash2, 64-bit versions, by Austin Appleby