None of these require arbitrary amounts of repeated addition though. E.g. multiplying two 8 bit numbers requires at most 7 additions.

Yeah I did not mean a loop, repeated in the network.

Are you doing the equivalent of repeated squaring here?

Otherwise, you'd need up to 255 (or so) additions to multiply two 8 bit numbers, I think?

An 8x8 bit multiplication only requires 7 additions, either in parallel or sequentially. Remember long-form multiplication? [1] It's the same principle. Of course, high-speed digital multiplication circuits use a much more optimized, much more complex implementation.

[1] https://en.wikipedia.org/wiki/Multiplication_algorithm#Examp...

OK. It sounded to me like the comment I originally replied to (https://news.ycombinator.com/item?id=34400296) suggested to implement multiplication as naive repeated addition.