Exercise 3.

Translate the following MOOL piece of code into three-address code.

while not (a = b) repeat {
    if (a < b) then {
       b := b - a;
   } else {
       a := a - b;
   };
};

The three-address code instructions you may need are of one of the forms:

• goto L where L is a symbolic label (like L1, L2, ...)
• if x relop y goto L where relop can be = or <
• x:= y op z where op can be -

Moreover your solution does not need to be obtained by one of the algorithms of the course. Just consider that you are programming a very basic calculator.

Answer 3