probe process.function("foo").return {
    printf("x0 = %#x\n", register("x0"));
    printf("u x0 = %#x\n\n", u_register("x0"));

    printf("w0 = %#x\n", register("w0"));
    printf("u w0 = %#x\n", u_register("w0"));
    exit()
}
