dev/SELFTESTHash64WithSeed

{ uint64_t h = NAMESPACE::Hash64WithSeed(data + offset, len, SEED); cout << (h >> 32) << "u, " << ((h << 32) >> 32) << "u," << endl; }
{ uint64_t h = NAMESPACE::Hash64WithSeed(data + offset, len, SEED); Check(h >> 32); Check((h << 32) >> 32); }