- | r > 31 = FreeRegs g (f .&. complement (1 `shiftL` (fromIntegral r - 32)))
- | otherwise = FreeRegs (g .&. complement (1 `shiftL` fromIntegral r)) f
+ | r > 31 = FreeRegs g (f .&. complement (1 `shiftL` (r - 32)))
+ | otherwise = FreeRegs (g .&. complement (1 `shiftL` r)) f