-- Ackermann function

function ack(integer, integer) : integer {
  push 0;
  push arg[0];
  eq;
  br {
    true: {
      push 1;
      push arg[1];
      add;
      ret;
    }
    false: {
      push 0;
      push arg[1];
      eq;
      br {
        true: {
          push 1;
          push 1;
          push arg[0];
          sub;
          tcall ack;
        }
        false: {
          push 1;
          push arg[1];
          sub;
          push arg[0];
          call ack;
          push 1;
          push arg[0];
          sub;
          tcall ack;
        }
      };
    }
  };
}

function main() {
  push 7;
  push 0;
  call ack;
  trace;
  pop;

  push 7;
  push 1;
  call ack;
  trace;
  pop;

  push 13;
  push 1;
  call ack;
  trace;
  pop;

  push 7;
  push 2;
  call ack;
  trace;
  pop;

  push 13;
  push 2;
  call ack;
  trace;
  pop;

  push 4;
  push 3;
  call ack;
  trace;
  pop;

  push void;
  ret;
}