Senior judges may serve as judges of the superior courts as provided for in Chapter 1 of Title 15 or as otherwise provided by law. A senior judge serving as judge of the superior court shall be compensated as provided for in Code Section 15-1-9.2 or as otherwise provided by laws enacted after July 1, 1989; and such compensation for such service shall not affect, diminish, or otherwise impair the payment or receipt of any retirement or pension benefits of such judge.