test_vslw128_variable:
  #_ REGISTER_IN v3 [00000001, 00000001, 00000001, 00000001]
  #_ REGISTER_IN v4 [00000000, 00000001, 0000001F, 00000020]
  vslw128 v5, v3, v4
  blr
  #_ REGISTER_OUT v3 [00000001, 00000001, 00000001, 00000001]
  #_ REGISTER_OUT v4 [00000000, 00000001, 0000001F, 00000020]
  #_ REGISTER_OUT v5 [00000001, 00000002, 80000000, 00000001]