Why 90 degree rotations are not allowed for macro

[keyplay]

Hi, according to NETLIST_FORMAT, 90 degree rotations are not allowed for macro. May I know the reason?

[sakundu]

This is a design rule.

If you rotate a macro by 90 degrees, it will change the orientation of the poly and fin direction of that macro, causing misalignment.

In the design, the poly and fin direction for all macros and standard cells must align. Therefore, 90-degree rotations are not allowed.