[enhancement] Gracefully support multiple observers in IR evaluators #3307
Description
What's hard to do? (limit 100 words)
In an upcoming CL, I should be landing something to eval_{ir, proc}_main that lets you choose between different observers to use when evaluating the RTL. Ideally, it would be easier to have multiple observers registered with an evaluator.
Current best alternative workaround (limit 100 words)
Run eval_{ir, proc}_main multiple times with each observer.
Your view of the "best case XLS enhancement" (limit 100 words)
You should be able to register an arbitrary number of observers.