As for the divide checkbox not being available under cyclone, I'll look into this.
I believe it is just a packaging choice that you only can get divide if you get multiply.
Since there is no multiply on cyclone, there is no divide.
However, I designed divide to be independent of multiply so it should work fine.
What's required is some PTF changes. How about you email your Nios II class.ptf and
your system.ptf and I'll see about making the changes? My email is
jball@altera.com.
As for multiply, you could use a custom instruction but there is no way to get the compiler
to use it when you use the * operator. You'll have to change all your source code that
wants to use the fast multiply to call the multiply instruction instruction. There are macros
defined for you by SOPC Builder that will call a custom instruction from C-code or assembly.