Worry about performance hit on double precision float numbers arguments

[crazyyi]

I am researching bit packing technologies in javascript and I come across this module. I am making a game too so I am glad this is born for games. The problem is javascript only supports integer bitwise operation. But unlike other languages, javascript numbers are double precision float numbers. So the numbers in the arguments need to be converted to integer before bit shifting and other bit operations. Does that have any negative performance impact?