Pin swap

Pin swap. A multi-input gate's inputs are logically interchangeable, but they are not electrically equal: each input pin has its own pin-to-output delay. The gate's output is ready at the worst of (signal arrival + that pin's delay) across all inputs. If the latest-arriving signal happens to sit on the slowest pin, the path through the gate is longer than it needs to be.

The fix costs no area: just rewire. Move the late signal onto a faster pin and push the early signals onto the slower pins. Nothing about the cell changes, only which wire lands on which input.

Click two input pins to swap the signals feeding them. Get the output at or under the required time, then Submit wiring.