* Redundant hop_to_executor elimination: if a hop_to_executor is dominated by another hop_to_executor with the same operand, it is eliminated:
hop_to_executor %a
... // no suspension points
hop_to_executor %a // can be eliminated
* Dead hop_to_executor elimination: if a hop_to_executor is not followed by any code which requires to run on its actor's executor, it is eliminated:
hop_to_executor %a
... // no instruction which require to run on %a
return
rdar://problem/70304809