The code below describes the fetch-execute algorithm for a sequential control unit. The discussion of the control unit informally describes how a machine can be made to run much faster by overlapping the fetch and execute operations. List the steps necessary to accomplish this overlap by explaining any new registers that might be needed, indicating which control unit components operate at the same time, and rewriting the fetch-execute algorithm.

PC = ;

IR = memory [PC];

haltFlag = CLEAR;

while (haltFlag not SET during execution) {

PC = PC + 1;

execute(IR);

IR = memory[Pc];

};