test_vpkpx_1:
  #_ REGISTER_IN v3 [00101820, 01283038, 00404850, 01586068]
  #_ REGISTER_IN v4 [01707880, 00889098, 01A0A8B0, 00B8C0C8]
  vpkpx v5, v3, v4
  blr
  #_ REGISTER_OUT v3 [00101820, 01283038, 00404850, 01586068]
  #_ REGISTER_OUT v4 [01707880, 00889098, 01A0A8B0, 00B8C0C8]
  #_ REGISTER_OUT v5 [086494C7, 212AAD8D, B9F04653, D2B65F19]

test_vpkpx_2:
  #_ REGISTER_IN v3 [FFFF0000, FF00FF00, FF0000FF, FFFFFFFF]
  #_ REGISTER_IN v4 [FF000000, FF808080, FFC0C0C0, FF404040]
  vpkpx v5, v3, v4
  blr
  #_ REGISTER_OUT v3 [FFFF0000, FF00FF00, FF0000FF, FFFFFFFF]
  #_ REGISTER_OUT v4 [FF000000, FF808080, FFC0C0C0, FF404040]
  #_ REGISTER_OUT v5 [FC0083E0, 801FFFFF, 8000C210, E318A108]

test_vpkpx_3:
  #_ REGISTER_IN v3 [00000000, 00000000, 00000000, 00000000]
  #_ REGISTER_IN v4 [FFFFFFFF, FFFFFFFF, FFFFFFFF, FFFFFFFF]
  vpkpx v5, v3, v4
  blr
  #_ REGISTER_OUT v3 [00000000, 00000000, 00000000, 00000000]
  #_ REGISTER_OUT v4 [FFFFFFFF, FFFFFFFF, FFFFFFFF, FFFFFFFF]
  #_ REGISTER_OUT v5 [00000000, 00000000, FFFFFFFF, FFFFFFFF]

test_vpkpx_4:
  #_ REGISTER_IN v3 [80000000, 80FFFFFF, 7FFFFFFF, 7F000000]
  #_ REGISTER_IN v4 [FF123456, FF789ABC, FFABCDEF, FFFEDCBA]
  vpkpx v5, v3, v4
  blr
  #_ REGISTER_OUT v3 [80000000, 80FFFFFF, 7FFFFFFF, 7F000000]
  #_ REGISTER_OUT v4 [FF123456, FF789ABC, FFABCDEF, FFFEDCBA]
  #_ REGISTER_OUT v5 [00007FFF, FFFF8000, 88CABE77, D73DFF77]

test_vpkpx_5:
  #_ REGISTER_IN v3 [FF204060, FF406080, FF6080A0, FF8090A0]
  #_ REGISTER_IN v4 [FFA0B0C0, FFC0D0E0, FFE0F0FF, FF102030]
  vpkpx v5, v3, v4
  blr
  #_ REGISTER_OUT v3 [FF204060, FF406080, FF6080A0, FF8090A0]
  #_ REGISTER_OUT v4 [FFA0B0C0, FFC0D0E0, FFE0F0FF, FF102030]
  #_ REGISTER_OUT v5 [910CA190, B214C254, D2D8E35C, F3DF8886]