Function OpsUsedByGraph

tensorflow/core/framework/graph_def_util.cc:166–209

}

void OpsUsedByGraph(const GraphDef& graph_def,
                    std::set<string>* ops_used_in_graph) {
  // Map function names to definitions.
  std::unordered_map<string, const FunctionDef*> name_to_function;
  for (const auto& function : graph_def.library().function()) {
    name_to_function.insert(
        std::make_pair(function.signature().name(), &function));
  }

  // Collect the sorted list of op names.  Since functions can reference
  // functions, we need a recursive traversal.
  std::set<string> used_ops;  // Includes both primitive ops and functions
  std::vector<const FunctionDef*> functions_to_process;  // A subset of used_ops
  // Collect the logic to mark an op in a lambda; it'll be used twice below.
  const auto mark_op_as_used = [&used_ops, &functions_to_process,
                                &name_to_function](const string& op) {
    if (used_ops.insert(op).second) {
      // If it's a function, we'll need to process further
      const auto it = name_to_function.find(op);
      if (it != name_to_function.end()) {
        functions_to_process.push_back(it->second);
      }
    }
  };
  for (const auto& node : graph_def.node()) {
    mark_op_as_used(node.op());
  }
  while (!functions_to_process.empty()) {
    const FunctionDef* fun = functions_to_process.back();
    functions_to_process.pop_back();
    for (const auto& node : fun->node_def()) {
      mark_op_as_used(node.op());
    }
  }

  // Filter out function names to produce output.
  // TODO(josh11b): Change the above code to produce this directly.
  ops_used_in_graph->clear();
  for (const string& op_name : used_ops) {
    if (name_to_function.find(op_name) == name_to_function.end()) {
      ops_used_in_graph->insert(op_name);
    }
  }
}

Status StrippedOpListForGraph(const GraphDef& graph_def,
                              const OpRegistryInterface& op_registry,