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The !rmpcprops Command: Remove PCell Properties

Syntax: !rmpcprops [-a]
Warning: this operation is not undoable.

This command applies to all cells in the hierarchy of the current physical cell. There are two passes made through the hierarchy. On the first pass, cells that are parameterized cell (pcell) sub-masters may have their pc_name and pc_params properties removed. This will be true for ``foreign'' pcells created in and imported from another tool or library such as OpenAccess, and if -a is given, this will also apply to native pcells. Once these properties are removed from a pcell sub-master. the cell becomes in all respects an ordinary cell.

On the second pass, the masters of cell instances that have pcell properties are checked, and if the master does not have pcell properties (they were likely removed in the first pass), the instance pcell properties are removed.

Running this command will remove any ambiguity about whether sub-master cells will be saved to an archive (they will always be saved, since they are now normal cells), and there will never be an attempt to resolve placements of the cells by executing a super-master (instances are no longer seen as pcell placements). All history that the cell was once created from a pcell super-master is gone.

This command is not undoable. Once the properties are stripped, there is no way to put them back, except perhaps very laboriously by hand. Don't use this command unless you want all pcell history in the current cell hierarchy to go away forever.

When importing design data from Cadence Virtuoso, for example, using the Express PCell feature to obtain pcell sub-masters, you may wish to use this command on the new hierarchy. In Xic, the pcells can not be evaluated anyway, and their presence may cause trouble. For example, if the hierarchy is saved to disk as a GDSII or other archive file, by default the sub-masters are not written. When reading this file at some future time, unless the Virtuoso database is present and able to provide the sub-masters, the pcell instances won't be resolved. Thus you must remember to explicitly enable saving the sub-masters when writing output, unless you have used the !rmpcprops command.


next up previous contents index
Next: The !preload Command: Pre-Load Up: Parameterized Cells Previous: Parameterized Cells   Contents   Index
Stephen R. Whiteley 2022-05-28