Dennis Richie reports that the increment operators actually came from B on the PDP-7. It didn't have auto-increment addressing modes, but it did have memory loc

Dennis Richie reports that the increment operators actually came from B on the PDP-7. It didn't have auto-increment addressing modes, but it did have memory locations which increment when read. "This feature probably suggested such operators to Thompson; the generalization to make them both prefix and postfix was his own. Indeed, the auto-increment cells were not used directly in implementation of the operators, and a stronger motivation for the innovation was probably his observation that the translation of ++x was smaller than that of x=x+1." https://www.bell-labs.com/usr/dmr/www/chist.html https://www.bell-labs.com/usr/dmr/www/chist.html