public override void CGenStmt(Env env, CGenState state) {
Reg ret = CGenExprStmt(env, this.Cond, state);
Int32 finish_label = state.RequestLabel();
CGenTest(ret, state);
state.JZ(finish_label);
this.Stmt.CGenStmt(env, state);
state.CGenLabel(finish_label);
}
}