{"ast_node_type":"variable","tokens":[{"end":94,"kind":"keyword","start":0,"text":"let"}]}
        let mut pgo_func_name_var_map = self.coverage_cx().pgo_func_name_var_map.borrow_mut();
        debug!("getting pgo_func_name_var for instance={:?}", instance);
        pgo_func_name_var_map.entry(instance).or_insert_with(|| {