Adds node to function manager, converting address to CodeNode if
        possible

        :param CFGNode cfg_node:    A CFGNode instance.
        :param int function_addr:   Address of the current function.
        :return: None

def _function_add_node(self, cfg_node, function_addr):
        """
        Adds node to function manager, converting address to CodeNode if
        possible

        :param CFGNode cfg_node:    A CFGNode instance.
        :param int function_addr:   Address of the current function.
        :return: None
        """
        snippet = self._to_snippet(cfg_node=cfg_node)
        self.kb.functions._add_node(function_addr, snippet)