ECU knows the current boost pressure, and can compensate for it.
I can promise you the ecu doesnt "compensate" for it. I run my 2bar car at 3 bar worth of boost without issues, and have setup more than a few cars without map sensors. Even if you told the ecu to "compensate for boost" its completely illogical to calculate anything off a map sensor when you have a MAF sensor.

Have fun with a broken car with the answer sitting right in front of you.