out.dot

digraph g {
  d1 [label=b1];
  b1 [label="b1: Entry: [int n]"];
  b1 -> b2;
  d2 [label=b2];
  d1 -> d2;
  b2 [shape=box, label="b2:\nx₁ = 0"];
  b2 -> b3;
  d3 [label=b3];
  d2 -> d3;
  b3 [shape=box, label="b3:\ny₁ = 1"];
  b3 -> b4;
  d4 [label=b4];
  d3 -> d4;
  b5 [shape=box, label="b5:\nw₁ = φ(w₀, w₂)\nx₂ = φ(x₁, x₃)\ny₂ = φ(y₁, y₃)\nz₂ = φ(z₁, z₃)\n(< z₂ n₀)?"];
  b5 -> b6 [label=true];
  b5 -> b10 [label=false];
  d5 [label=b5];
  d4 -> d5;
  b4 [shape=box, label="b4:\nz₁ = 3"];
  b4 -> b5;
  d6 [label=b6];
  d5 -> d6;
  b6 [shape=box, label="b6:\nw₂ = (+ x₂ y₂)"];
  b6 -> b7;
  d7 [label=b7];
  d6 -> d7;
  b7 [shape=box, label="b7:\nx₃ = y₂"];
  b7 -> b8;
  d8 [label=b8];
  d7 -> d8;
  b8 [shape=box, label="b8:\ny₃ = w₂"];
  b8 -> b9;
  d9 [label=b9];
  d8 -> d9;
  b9 [shape=box, label="b9:\nz₃ = (+ z₂ 1)"];
  b9 -> b5;
  d10 [label=b10];
  d5 -> d10;
  b10 [label="b10: RETURN y₂"];
}