message: Tolerate dead CFG nodes
diff: @@ -51,7 +51,7 @@ def get_dom(succ, entry):
  pred = map_inv(succ)
  nodes = list(reversed(postorder(succ, entry))) # Reverse postorder.
  - dom = {v: set(nodes) for v in nodes}
  + dom = {v: set(nodes) for v in succ}
  while True:
  changed = False
  