Method NodeHash

tensorflow/core/graph/optimizer_cse.cc:91–123

static size_t kIllegalNodeHash = 0;

size_t OptimizerCSE::NodeHash(const Node* n) {
  const DataTypeVector& out = n->output_types();
  string str_to_hash = strings::StrCat(n->type_string(), out.size());
  for (DataType dt : out) {
    strings::StrAppend(&str_to_hash, dt);
  }

  const int N_in = n->num_inputs();
  strings::StrAppend(&str_to_hash, N_in);
  gtl::InlinedVector<const Node*, 4> control_edges;
  gtl::InlinedVector<std::pair<const Node*, int>, 4> in(N_in);
  FillInputs(n, &control_edges, &in);
  for (const auto& edge : in) {
    strings::StrAppend(&str_to_hash, edge.first->id(), edge.second);
  }

  size_t h = Hash64(str_to_hash);

#if !defined(__ANDROID__)
  // Hash the attrs.  For example, this makes sure different constants
  // end up in different hash buckets.
  string tmp;
  for (const auto& attr : n->attrs()) {
    tmp = attr.first;
    attr.second.AppendToString(&tmp);
    // Add hashes of attrs, so the order of attrs doesn't matter.
    h += Hash32(tmp.data(), tmp.size(), 0x87341245);
  }
#endif

  if (h == kIllegalNodeHash) h = kIllegalNodeHash + 1;
  return h;
}

static bool HasRefInput(const Node* n) {
  for (auto dt : n->input_types()) {