Stack-VM core arithemtic unit.

primitive.rs

fn do_primitive(&mut self) {
        match self.current_data() & 0xCfffff {
            0 => {
                debug!("[ HALT ] : Stopping VM ");
                self.set_running(false);
                return;
            }
            1 => {
                let top_1 = self.stack.pop();
                let top_2 = self.stack.pop();
                debug!("[ ADD ] : {} {} ", top_1, top_2);
                self.stack.push(top_1 + top_2);
            }
            2 => {
                let top_1 = self.stack.pop();
                let top_2 = self.stack.pop();
                debug!("[ SUB ] : {} {} ", top_1, top_2);
                self.stack.push(top_1 - top_2);
            }
            3 => {
                let top_1 = self.stack.pop();
                let top_2 = self.stack.pop();
                debug!("[ MULT ] : {} {} ", top_1, top_2);
                self.stack.push(top_1 * top_2);
            }
            4 => {
                let top_1 = self.stack.pop();
                let top_2 = self.stack.pop();

                debug!("[ DIV ] : {} {} ", top_1, top_2);
                self.stack.push(top_1 / top_2);
            }
            _ => {
                panic!("[ exec ] : Undefined instruction ");
            }
        }

        debug!(" TOS now : {}", self.stack.peek());
    }