Timing driven cell swapping

1. A method for cell swapping, the method comprising:

determining a cell violating a physical design constraint associated with a circuit;

determining a location for swapping the cell;

determining a plurality of cell versions of the cell for placement at the location;

determining a cell version from the plurality of cell versions based on displacement information associated with each of the plurality of cell versions; and

swapping the cell with the cell version.

2. The method of claim 1 , wherein determining the plurality of cell versions for placement at the location comprises:

determining a plurality of legal positions for cell placement at the location; and

determining the plurality of cell versions for placement at the plurality of legal positions.

3. The method of claim 2 , wherein determining the plurality of legal positions at the location comprises determining the plurality of legal locations using a location searching window.

4. The method of claim 1 , wherein determining the location for swapping the cell comprises:

identifying a first location associated with the cell;

determining that the first location is not a legal location for the cell placement; and

determining, in response to determining that the first location is not the legal location, a second location comprising the legal location for the cell placement.

5. The method of claim 1 , wherein determining the plurality of cell versions comprises determining the plurality of cell versions of a cell type associated with the cell.

6. The method of claim 5 , wherein determining the plurality of cell versions of the cell type associated with the cell comprises determining the plurality of cell versions, of the cell type associated with the cell, having associated physical design constraint not violating a physical design constraint of a circuit when placed at a respective legal position.

7. The method of claim 1 , further comprising:

creating a photomask of an integrated circuit comprising the cell version; and

fabricating the integrated circuit based on the created photomask.

8. A system for cell swapping, the system comprising:

a memory storage having instructions stored thereon; and

a processing unit coupled to the memory storage, wherein the processing unit is operative to execute the instructions, and wherein the instructions when executed by the processing unit are operative to:

determining a location for swapping a first cell;

determining a plurality of cells for placement at the location;

determining a second cell from the plurality of cells based on displacement information associated with each of the plurality of cells; and

swapping the first cell with the second cell.

9. The system of claim 8 , wherein the processing unit being operative to determine the plurality of cells for placement at the location comprises the processing unit being operative to:

determine a plurality of legal positions for cell placement at the location; and

determine the plurality of cells for placement at the plurality of legal positions.

10. The system of claim 9 , wherein the plurality of legal locations are determined using a location searching window.

11. The system of claim 8 , wherein the processing unit being operative to determine the location for swapping the first cell comprises the processing unit being operative to:

identify a first location associated with the first cell;

determine that the first location is not a legal location for the cell placement; and

determine, in response to determining that the first location is not the legal location, a second location comprising the legal location for the cell placement.

12. The system of claim 8 , wherein the processing unit being operative to determine the second cell from the plurality of cells based on displacement information comprises the processing unit being operative to:

determine a minimum displacement for each of the plurality of cells; and

determine the second cell from the plurality of cells that minimizes the minimum displacement and a cell delay.

13. The system of claim 8 , wherein the processing unit being operative to determine the second cell from the plurality of cells based on displacement information comprises the processing unit being operative to:

determine a maximum displacement for each of the plurality of cells; and

determine the second cell from the plurality of cells that maximizes a cell delay and the maximum displacement.

14. The system of claim 13 , wherein the processing unit being operative to determine the maximum displacement comprises the processing unit being operative to determine the maximum displacement from an initial position of a location searching window employed to determine the plurality of legal positions.

15. The system of claim 8 , wherein the processing unit is further operative to:

create a photomask of an integrated circuit comprising the second cell; and

fabricate the integrated circuit based on the created photomask.

16. A non-transitory computer-readable medium that stores a set of instructions which when executed perform a method for cell swapping, the method executed by the set of instructions comprising:

determining a cell violating a physical design constraint associated with a circuit;

determining a location for swapping the cell;

determining a plurality of legal positions for cell placement at the location;

determining a plurality of cell versions of the cell for the plurality of legal positions;

determining a cell version from the plurality of cell versions based on displacement information associated with each of the plurality of cells; and

swapping the cell with the cell version.

17. The non-transitory computer-readable medium of claim 16 , wherein determining the location for swapping the cell comprises:

identifying a first location associated with the cell;

determining that the first location is not a legal location for the cell placement; and

determining, in response to determining that the first location is not the legal location, a second location comprising the legal location for the cell placement.

18. The non-transitory computer-readable medium of claim 16 , wherein the displacement information comprises a minimum displacement and a maximum displacement of each of the plurality of legal positions at the determined location.

19. The non-transitory computer-readable medium of claim 16 , wherein the cell version is determined to minimize a displacement and minimize a cell delay.

20. The non-transitory computer-readable medium of claim 16 , wherein the cell version is determined to maximize a displacement and minimize a cell delay.