[rjjj]

Those kinds of things are still done using description languages such as VHDL and Verilog. Basically :



1 - Bitwise operations are combined to create the addition and subtraction operations.


2 - Memory logic (clocked) is used to create primitive loops through electrical feedback.


3 - Using the addition operation many times, one can make the multiplication. There is a similar relationship between the subtraction and the division.




I hope that I have helped .