Method and apparatus for selecting components within a circuit design database

• US 6,684,376 B1
• Filed: 01/27/1997
• Issued: 01/27/2004
• Est. Priority Date: 01/27/1997
• Status: Expired due to Fees

• Current Assignee: Unisys Corporation
• Original Assignee: Unisys Corporation
• Inventors: Kerzman, Joseph P., Rezek, James E., Alferness, Merwin H., Aubel, Mark D.
• Primary Examiner(s): JONES, HUGH M
• Application Number:
  US08/789,026
• Time in Patent Office: 2,556 Days
• Field of Search: 364/488, 364/489, 364/490, 364/491, 716/8, 716/9-10
• US Class Current: 716/124
• CPC Class Codes: G06F 30/392 Floor-planning or layout, e.g. partitioning or placement

Abstract

A method and apparatus for efficiently selecting cells within a circuit design database. The invention includes four primary features for selecting cells including (1) selecting only those cells that are in a pre-identified region and within a pre-identified selection area; (2) maneuvering through the circuit design hierarchy and selecting cells or regions at selected levels of hierarchy by using predetermined up and down hot-keys; (3) sorting selected cells by instance name, and manually selecting a desired cell or region from the resulting sorted list; and (4) sorting selected cells by a corresponding net name, and manually selecting a desired cell or region from the resulting sorted list.

Claims

1. A method for selecting a number of items within a circuit design database using a placement tool wherein the placement tool displays at least a portion of the circuit design database on a display device, the circuit design database including a number regions wherein each of the number of regions reference selected ones of the number of items, the method comprising the steps of:

a. selecting one of the number of regions, thereby resulting in a current active region;

b. indicating a selection area on the display device wherein the selection area encompasses at least a portion of at least two of the number of regions including at least a portion of the current active region; and

c. selecting only those items that correspond to the current active region and that are represented within the selection area.

2. A method according to claim 1 wherein the at least two regions that are at least in part encompassed by the selection area are at least in part overlapping.

3. A method according to claim 2 wherein selected ones of the number of items are leaf cells.

4. A method according to claim 3 wherein selected ones of the number of items are regions.

5. A method for selecting a number of regions within a circuit design database using a placement tool comprising:

a. arranging the circuit design database to include a number of levels of hierarchy and a number of regions;

b. displaying at least two regions at least in part, simultaneously on a display device;

c. referencing selected ones of the number of regions by a corresponding region at a higher level in the design hierarchy;

c. moving a cursor over a desired portion of the displayed circuit design on the display device;

d. moving the cursor to a cursor location, wherein the cursor location is encompassed at least in part by at least two of the displayed regions; and

e. depressing at least one predetermined down hot-key, causing the placement tool to select a selected one of the at least two displayed regions to the exclusion of the other at least two displayed regions.

6. A method according to claim 5 further comprising the steps of sequentially depressing the at least one predetermined down hot-key to sequentially select each of the at least two displayed regions that encompasses said cursor location.

7. A method according to claim 5 further comprising the step of:

a. depressing at least one predetermined up hot-key, causing the placement tool to select the corresponding region that references the selected one of the at least two displayed regions.

8. A method for selecting instances within a circuit design database for placement using a placement tool comprising the steps of:

a. allocating the circuit design database into a number of instances;

b. associating an instance name with each of the number of instances;

c. identifying a number of selected instances including the step of identifying those instances that are un-placed;

d. sorting the number of selected instances, thereby resulting in a sorted instance list; and

e. selecting an instance from the sorted instance list for placement.

9. A method according to claim 8 wherein the number of selected instances are sorted alphabetically by their instance names.

10. A method according to claim 9 wherein selected ones of the number of selected instances are regions.

11. A method according to claim 8 wherein the circuit design database has a number of levels of hierarchy, wherein each of the number of levels of hierarchy are called contexts, and wherein selected ones of the contexts reference predetermined ones of the number of instances.

12. A method according to claim 11 further comprising the step of selecting one of the contexts, thereby resulting in a selected context.

13. A method according to claim 12 wherein said identifying step identifies only those un-placed instances that are referenced within the selected context.

14. A method for selecting instances within a circuit design database for placement using a placement tool, the method comprising the steps of:

a. dividing the circuit design database into a number of instances;

b. coupling selected ones of the number of instances to predetermined other ones of the number of instances via at least one net;

c. assigning to selected nets predefined net names;

d. identifying a number of selected instances including the step of identifying those instances that are un-placed;

e. sorting the selected instances, according to a predetermined one of the net names associated with each of the selected instances, thereby resulting in a sorted instance list; and

f. selecting an instance from the sorted instance list for placement.

15. A method according to claim 14 wherein said sorting step sorts the selected instances by sorting the net names associated therewith alphabetically.

16. A method according to claim 15 wherein said sorting step sorts the selected instances by sorting the net names associated with a pre-identified output of each instance.

17. A method according to claim 15 wherein selected ones of the selected instances are regions.

18. A method according to claim 14 wherein the circuit design database has a number of levels of hierarchy, wherein each of the number of levels of hierarchy are called contexts, and wherein selected ones of the contexts reference predetermined ones of the number of instances.

19. A method according to claim 18 further comprising the step of selecting one of the contexts, thereby resulting in a selected context.

20. A method according to claim 19 wherein said identifying step identifies only those selected instances that are referenced within the selected context.

21. A method according to claim 14 further comprising the steps of:

a. placing the selected instance, thereby resulting in a first placed cell;

b. specifying a placement direction, relative to the first placed cell; and

c. depressing a number of predefined hot-keys, causing a next subsequent instance in the sorted instance list to be placed a predetermined distance from the first placed cell, in the placement direction.

22. A data processing system comprising:

a. means for selecting a number of items within a circuit design database wherein the data processing system displays at least a portion of the circuit design database on a display device, the circuit design database including a number regions wherein each of the number of regions reference selected ones of the number of items;

b. first selecting means for selecting one of the number of regions, thereby resulting in a current active region;

c. indicating means coupled to said selecting means for indicating a selection area on the display device, wherein the selection area encompasses at least a portion of at least two of the number of regions including at least a portion of the current active region; and

d. second selecting means coupled to said indicating means and to said first selecting means for selecting only those items that correspond to the current active region and that are represented within the selection area.

23. A data processing system according to claim 22 wherein the at least two regions that are at least in part encompassed by the selection area are at least in part overlapping.

24. A data processing system comprising:

a. a number of regions within a circuit design database, the circuit design database including a number of levels of hierarchy and a number of regions, wherein at least two regions are, at least in part, simultaneously displayed on a display device, selected ones of the number of regions being referenced by a corresponding region at a higher level in the design hierarchy, the placement tool allowing a user to move a cursor over a desired portion of the displayed circuit design on the display device;

b. moving means for moving the cursor to a cursor location, wherein the cursor location is encompassed at least in part by at least two of the displayed regions; and

c. hot-key means for causing the data processing system to select a selected one of the at least two displayed regions to the exclusion of the other at least two displayed regions.

25. A data processing system comprising:

a. a circuit design database, wherein the circuit design database includes a number of instances, and wherein each of the number of instances has an instance name associated therewith;

b. identifying means for identifying a number of selected instances;

c. sorting means coupled to said identifying means for sorting the number of selected instances, thereby resulting in a sorted instance list;

e. selecting means coupled to said sorting means for selecting an instance from the sorted instance list;

f. wherein said sorting means sorts the number of selected instances alphabetically by their instance names; and

g. wherein said identifying means identifies only those instances that are un-placed.

26. A data processing system comprising:

a. a circuit design database, wherein the circuit design database includes a number of instances, and wherein selected ones of the number of instances are coupled to predetermined other ones of the number of instances via at least one net, wherein selected nets have predefined net names;

b. identifying means for identifying a number of selected instances;

c. sorting means coupled to said identifying means for sorting the selected instances, according to a predetermined one of the net names associated with each of the selected instances, thereby resulting in a sorted instance list;

d. selecting means coupled to said sorting means for selecting an instance from the sorted instance list;

f. placing means for placing the selected instance at a selected location within the circuit design, thereby resulting in a first placed cell;

g. specifying means for specifying a placement direction, relative to the first placed cell; and

h. hot-keys means coupled to said placing means and said specifying means for causing a next subsequent instance in the sorted instance list to be placed a predetermined distance from the first placed cell, in the placement direction.

27. A data processing system according to claim 26 wherein said sorting means sorts the selected instances alphabetically according to the net associated therewith.

28. A data processing system according to claim 27 wherein said sorting means sorts the selected instances by sorting the net names associated with a pre-identified output of each instance.