walpurgis/graphviz/global_flow.dot

digraph flow {
  // Global settings
  graph [fontname = "cc wild words"];
  node [fontname = "cc wild words"];
  edge [fontname = "cc wild words"];
  rankdir=LR;

  A0 [label="Global" style=filled fillcolor=gold];
  C0 [label="end generation"];
  D0 [label="for each undefined subroutine"];
  F0 [label="return" style=filled fillcolor=lightskyblue1];

  node [shape=diamond style=filled fillcolor=lightsalmon];
  FA0 [label="fn_gen_global_decl()"];
  FB0 [label="fn_gen_main()"];
  FC0 [label="fn_define_subroutine(SubRoutine)"];
  FD0 [label="fn_declare_subroutine()"];
  FE0 [label="fn_gen_typedef()"];

  A0 -> FA0 -> A0;
  A0 -> C0 -> FB0 -> D0;
  A0 -> FD0 -> A0;
  A0 -> FE0 -> A0;
  D0 -> FC0 -> D0;
  D0 -> F0;
}