public TraceSchedule steppedBackward(Trace trace, long stepCount) {
		return doSteppedBackward(trace, stepCount, new HashSet<>());
	}
Returns the equivalent of executing count instructions (and all p-code operations) less than
this schedule

<p>
This schedule is left unmodified. If it had any p-code steps, those steps and subsequent
patches are dropped in the resulting schedule. If count exceeds this schedule's steps, it
will try (recursively) to step the source snapshot's schedule backward, if known. Both ticks
and patches counts as steps.

@param trace the trace of this schedule, for context
@param stepCount the number of steps to take backward
@return the resulting schedule or null if it cannot be computed
Ghidra/Debug/Framework-TraceModeling/src/main/java/ghidra/trace/model/time/schedule/TraceSchedule.java