free_verifier_state
free_verifier_state(&sl->state, false);
free_verifier_state(&backedge->state, false);
free_verifier_state(&backedge->state, false);
free_verifier_state(new, false);
free_verifier_state(new, false);
free_verifier_state(&head->st, false);
free_verifier_state(env->cur_state, true);
free_verifier_state(&sl->state, false);
free_verifier_state(&sl->state, false);