Function CombineHash

tensorflow/core/grappler/graph_analyzer/hash_tools.h:29–31

Unfortunately, std::hash provides no way to combine hashes, so everyone is copying boost::hash_combine. This is a version that follows Google's guidelines on the arguments, and contains only the combination, without hashing.

// guidelines on the arguments, and contains only the combination, without
// hashing.
inline void CombineHash(size_t from, size_t* to) {
  *to ^= from + 0x9e3779b9 + (*to << 6) + (*to >> 2);
}

// Combine two hashes in such a way that the order of combination doesn't matter
// (so it's really both commutative and associative). The result is not a very