[prestonbriggs]

Disgusting indeed: A way to write irreducible loops that doesn't use a goto. Good idea to measure the resulting code, given how poorly most optimizers deal with such loops.

Even sadder because the same effect can be achieved cleanly (and "optimizably")by using as "switch" followed by a "while".

[andrath]

You should read Tom Duff's original email about this:

https://www.lysator.liu.se/c/duffs-device.html

A quote of the man himself about this: "I feel a combination of pride and revulsion at this discovery."