Interesting that you bring up forth. As an educational exercise, I did the same thing. I took http://www.annexia.org/forth (Jones Forth) and coded it up on an AVR microcontroller. What did I cover - Subversion, AVR assembler, threaded code and shift division. I’ve done shift multiplication but shift division was all new. http://www.tofla.iconbar.com/tofla/arm/arm02/index.htm
Think of replicating experiments done by others.