Barbell whip is just how the bar bends. Manufacturers actually test this. If they create a bar that has no whip at all, it's advertised as a stiff bar.
Deadlift barbells commonly have a fair amount of good whip built into them. They bend fast and let you start moving the barbell before the weight is moving. Olympic weightlifting barbells also should have some whip but I would think they'd want less... Not really familiar with that world. Generally, it's something that has been intentionally built into the bar...
However, cheap barbells will also have whip just because they're cheap and they are real bendy. Good barbells should be able to bend but go back to their normal state when the force is removed... See the Joe Sullivan squat video.
Squats are a good lift to not have any whip in the barbell. It'll bend up and down if you have too much weight and the force will feel like you're getting nailed into the floor.