test_extswx_1:
  #_ REGISTER_IN r4 0x000000007FFFFFFF
  extsw. r3, r4
  blr
  #_ REGISTER_OUT r3 0x000000007FFFFFFF
  #_ REGISTER_OUT r4 0x000000007FFFFFFF

test_extswx_2:
  #_ REGISTER_IN r4 0x0000000080000000
  extsw. r3, r4
  blr
  #_ REGISTER_OUT r3 0xFFFFFFFF80000000
  #_ REGISTER_OUT r4 0x0000000080000000

test_extswx_3:
  #_ REGISTER_IN r4 0x00000000FFFFFFFF
  extsw. r3, r4
  blr
  #_ REGISTER_OUT r3 0xFFFFFFFFFFFFFFFF
  #_ REGISTER_OUT r4 0x00000000FFFFFFFF

test_extswx_4:
  #_ REGISTER_IN r4 0x0000000000000001
  extsw. r3, r4
  blr
  #_ REGISTER_OUT r3 0x0000000000000001
  #_ REGISTER_OUT r4 0x0000000000000001