Look into your AutoIt installation. In the "include" subfolder you should find the file GUIConstantsEx.au3 where those constants are defined:
Global Const $GUI_SHOW = 16
Global Const $GUI_HIDE = 32
Global Const $GUI_ENABLE = 64
Global Const $GUI_DISABLE = 128
The reason you get the value of 80 is because this is a bit mask and the control actually has 2 states: It is enabled and shown, so:
$GUI_SHOW = 16
$GUI_ENABLE = 64
The sum is 80 and that's what you got in your output.
Edit: If you want to test the state of a control for a specific state, for example to toggle the state of a button, then you can use the BitAND operator:
If BitAND(GUICtrlGetState($cmdOk), $GUI_DISABLE) = $GUI_DISABLE Then
GUICtrlSetState($cmdOk, $GUI_ENABLE)
EndIf