If someone says branching without qualification, I have to assume it’s incoherent. The branching mechanics might have lower overhead today, but the basic physics of the situation is that throughput on each side of the branch is reduced to the percentage of active threads. If both sides of a branch are taken, and both sides are the same instruction length, the average perf over both sides is at least cut in half. This is why the belief that branches are slow on GPUs is both persistent and true. And this is why it’s worth trying harder to reformulate the problem without branching, if possible.