Class Visit

tensorflow/compiler/jit/extract_outside_compilation_pass.cc:1238–1241

Reverse DFS from send_from_host_main_graph, and stop at start_node.

    Node* start_node = pivot_node ? pivot_node : host_graph->source_node();
    // Reverse DFS from send_from_host_main_graph, and stop at start_node.
    struct Visit {
      Node* n;
      bool is_exiting;
    };
    std::vector<Visit> stack{{send_node_in_host_graph, false}};
    std::map<Node*, Node*> node_map;
    node_map[host_graph->source_node()] = g->source_node();