Function GraphToFunctionDef

tensorflow/c/c_api_function.cc:305–481

Graph to FunctionDef conversion. This code is closely modeled on the Python function graph_to_function_def(), which is located in tensorflow/python/framework/graph_to_function_def.py.

// function graph_to_function_def(), which is located in
// tensorflow/python/framework/graph_to_function_def.py.
Status GraphToFunctionDef(const Graph& fn_body, const string& fn_name,
                          bool append_hash_to_fn_name,
                          const std::vector<const Node*>& body_nodes,
                          const std::vector<OutputTensor>& inputs,
                          const std::vector<OutputTensor>& outputs,
                          const std::vector<string>& output_names,
                          const std::vector<const Node*>& control_outputs,
                          const std::vector<string>& control_output_names,
                          const char* description, FunctionDef* fdef) {
  if (!output_names.empty()) {
    DCHECK_EQ(output_names.size(), outputs.size());
  }

  if (description != nullptr) {
    fdef->mutable_signature()->set_description(description);
  }

  // Keep track of names we used and how we normalized them.
  NodeNameMapping node_names;

  // Mapping from original names of tensors (i.e. "<node_name>:<idx>") to the
  // name we used in the function:
  //  - For input tensors:
  //    {flat_tensor_name -> normalized_name_of_src_node}
  //    e.g. {In:3 -> in}
  //  - For tensors produced by nodes in function's body:
  //    {flat_tensor_name -> nested_tensor_name}
  //    e.g. {Add:3 -> add_0:z:1}
  std::unordered_map<string, string> tensor_renaming;

  // Fill outputs in function's signature.
  // We fill the outputs first to prevent output_names from colliding
  // with the input names we pick below. With this order, no names are used in
  // node_names yet, and output_names won't collide with anything (except
  // potentially with themselves).
  for (size_t i = 0; i < outputs.size(); ++i) {
    const Node* node = outputs[i].node;
    int idx = outputs[i].index;
    OpDef::ArgDef* argdef = fdef->mutable_signature()->add_output_arg();
    argdef->set_type(node->output_type(idx));
    if (!output_names.empty()) {
      TF_RETURN_IF_ERROR(node_names.UseOutputName(output_names[i]));
      argdef->set_name(output_names[i]);
    } else {
      argdef->set_name(node_names.GetOutputName(node->name()));
    }
  }

  // Fill inputs in function's signature.
  for (size_t i = 0; i < inputs.size(); ++i) {
    const Node* node = inputs[i].node;
    int idx = inputs[i].index;
    OpDef::ArgDef* argdef = fdef->mutable_signature()->add_input_arg();
    argdef->set_type(node->output_type(idx));
    const string& input_name = node_names.GetInputName(node->name());
    argdef->set_name(input_name);
    auto& arg_attrs = (*fdef->mutable_arg_attr())[i];
    for (const auto& attr : node->attrs()) {