It looks like an early concept for Portage Place. The Bay Building on the right, a promenade where Portage Ave is, then the mall, a realigned Portage north of that, and then what I'm assuming is a residential building where the IG building is today.
This picture that was posted after shows the while site plan. Portage Place was originally planned to be far more substantial than what we got in the end.
Actually this seems to show even more detail. An aerial view looking north east from above Portage/Colony.