Abstract: Methods and apparatus for efficiently identifying, selecting and aligning cells within a circuit design are disclosed. Preferably, a net or group-of nets is first identified by the circuit designer. Then, selected cells that are connected to the selected net or group of nets are identified by the placement tool. A qualification or filter may be provided for filtering which cells are selected. For example, the filter may allow only those cells that are source cells, destination cells, placed cells, unplaced cells, etc., or any combination thereof to be selected. The selected cells may be aligned in a direction of an alignment axis, if desired.

Abstract: Methods and apparatus for efficiently identifying, selecting and aligning cells within a circuit design are disclosed. Preferably, a net or group of nets is first identified by the circuit designer. Then, selected cells that are connected to the selected net or group of nets are identified by the placement tool. A qualification or filter may be provided for filtering which cells are selected. For example, the filter may allow only those cells that are source cells, destination cells, placed cells, unplaced cells, etc., or any combination thereof to be selected. The selected cells may be aligned in a direction of an alignment axis, if desired.

Abstract: Method and apparatus for efficiently traversing and placing cells in a circuit design database are disclosed. In one illustrative embodiment, one or more leaf cells are identified as base objects. The base objects are placed and aligned along a selected dominate axis. Once the base objects are identified, an input port is identified by the circuit designer. In many cases, selected base objects will have at least one common input port name, such as “A”. By selecting a common input port name, the corresponding input port for each of the selected base objects is identified. Once identified, the source leaf cells that have an output port that is coupled to the identified input ports can be identified, placed and aligned as desired.