What checks are done after floorplan?

Area and Utilization: within limit.

Macro Placement Legality: Ensure all macros are placed legally (not overlapping) and are aligned to the site grid.

Pin Placement: Check that all I/O pins are placed and that their locations are reasonable for top-level connectivity.

Early IR Drop Analysis: A static IR drop analysis is run on the power distribution network (PDN) to check for significant voltage drops. This helps validate that the power grid structure (straps, rails, and vias) is robust enough.

Early Timing Estimation with trial placement of std cells. This "pre-placement" timing check helps identify if the floorplan is creating any gross timing violations due to long paths between connected macros or between macros and I/O pins.

Physical Verification Checks: Run initial DRC (Design Rule Checks) on the macros and power grid to ensure there are no fundamental physical violations