Function fmix64

test/flat_map_unittest.cpp:826–834

}

inline uint64_t fmix64 (uint64_t k) {
    k ^= k >> 33;
    k *= 0xff51afd7ed558ccdULL;
    k ^= k >> 33;
    k *= 0xc4ceb9fe1a85ec53ULL;
    k ^= k >> 33;

    return k;
}

template <typename T>
struct PointerHasher {