An apparatus, system and method for quickly determining an oldest
instruction in a non-moving instruction queue of a processor are
provided. Particularly, instructions are stored, one at a time at a clock
cycle, in the non-moving queue. At every clock cycle, a present status of
the instructions in the queue is recorded. Using the present status of
the instructions in the queue in conjunction with previously recorded
statuses of the instructions, the oldest instruction in the queue is
determined. The status of the instructions in the queue includes whether
or not the instruction has been issued for execution as well as whether
or not it is known that the issued instruction has been accepted for
execution.