test_extshx_1:
  #_ REGISTER_IN r4 0x0000000000007FFF
  extsh. r3, r4
  blr
  #_ REGISTER_OUT r3 0x0000000000007FFF
  #_ REGISTER_OUT r4 0x0000000000007FFF

test_extshx_2:
  #_ REGISTER_IN r4 0x0000000000008000
  extsh. r3, r4
  blr
  #_ REGISTER_OUT r3 0xFFFFFFFFFFFF8000
  #_ REGISTER_OUT r4 0x0000000000008000

test_extshx_3:
  #_ REGISTER_IN r4 0x000000000000FFFF
  extsh. r3, r4
  blr
  #_ REGISTER_OUT r3 0xFFFFFFFFFFFFFFFF
  #_ REGISTER_OUT r4 0x000000000000FFFF

test_extshx_4:
  #_ REGISTER_IN r4 0x0000000000000001
  extsh. r3, r4
  blr
  #_ REGISTER_OUT r3 0x0000000000000001
  #_ REGISTER_OUT r4 0x0000000000000001