digraph CFG {
  node [fontname="Helvetica"];
  n587 [label="START", shape=ellipse, style=filled, color=gray];
  n587 -> n606;
  n606 [label="10", shape=box];
  n606 -> n607;
  n607 [label="CALL f1", shape=box, style=filled, color=orange];
  n607 -> n589;
  n607 -> n609;
  n589 [label="START f1(b)", shape=ellipse, style=filled, color=green];
  n589 -> n592;
  n592 [label="b", shape=box];
  n592 -> n593;
  n593 [label="0", shape=box];
  n593 -> n594;
  n594 [label="b == 0", shape=box];
  n594 -> n595;
  n595 [label="<?>", shape=diamond];
  n595 -> n599 [label="T"];
  n595 -> n600 [label="F"];
  n599 [label="0", shape=box];
  n599 -> n590;
  n590 [label="END f1(b)", shape=ellipse, style=filled, color=green];
  n590 -> n605;
  n590 -> n609;
  n605 [label="RET f1", shape=box, style=filled, color=orange];
  n605 -> n590;
  n609 [label="RET f1", shape=box, style=filled, color=orange];
  n609 -> n588;
  n588 [label="END", shape=ellipse, style=filled, color=gray];
  n600 [label="b", shape=box];
  n600 -> n601;
  n601 [label="1", shape=box];
  n601 -> n602;
  n602 [label="b - 1", shape=box];
  n602 -> n603;
  n603 [label="CALL f1", shape=box, style=filled, color=orange];
  n603 -> n589;
  n603 -> n605;
}