code: static Node newCallNode(Node callTarget, Node... parameters) {
      boolean isFreeCall = !isGet(callTarget);
      Node call = IR.call(callTarget);
      call.putBooleanProp(Node.FREE_CALL, isFreeCall);
      for (Node parameter : parameters) {
        call.addChildToBack(parameter);
      }
      return call;
    }
docs: A new CALL node with the "FREE_CALL" set based on call target.