Method and apparatus for associating selected circuit instances and for performing a group operation thereon

• US 6,910,200 B1
• Filed: 01/27/1997
• Issued: 06/21/2005
• Est. Priority Date: 01/27/1997
• Status: Expired due to Fees

• Current Assignee: Unisys Corporation
• Original Assignee: Unisys Corporation
• Inventors: Aubel, Mark D., Nead, James M., Kerzman, Joseph P., Rezek, James E.
• Primary Examiner(s): JONES, HUGH M
• Application Number:
  US08/789,028
• Time in Patent Office: 3,067 Days
• Field of Search: 364/488, 364/489, 364/490, 716/1, 716 8- 14, 703/13
• US Class Current: 716/102
• CPC Class Codes: G06F 30/327 Logic synthesis; Behaviour synthesis, e.g. mapping logic, HDL to netlist, high-level language to RTL or netlist

Abstract

A method and apparatus for associating selected circuit instances, and for allowing a later group manipulation thereof. Prior to entering a database editor tool, selected instances may be associated with one another, and the association may be recorded in the circuit design database. The database editor tool may then read the circuit design database and identify the selected instances and the association therebetween. The associated instances may be called a group, or preferably a stack. The database editor tool may then perform a group operation on the instances associated with the stack.

Claims

1. A method for selectively associating a number of instances of a circuit design database, the method comprising the step of:

a. associating the number of instances with a predefined instance grouping called a stack by associating a selected stack identifier with each of the number of instances, wherein the selected stack identifier is stored in the circuit design database, and identifies each of the number of instances as corresponding to the stack;

b. selecting selected ones of the instances that correspond to the stack; and

c. performing a selected group operation on selected ones of the instances that correspond to the stack.

2. A method according to claim 1 wherein each of the number of instances has a corresponding instance name associated therewith, wherein each of the number of instance names are stored in the circuit design database.

3. A method according to claim 2 wherein said selected stack identifier for each of the number of instances is a selected portion of the corresponding instance name, wherein the selected portion of the instance name associates each of the number of instances with the stack.

4. A method according to claim 3 wherein the circuit design database includes a pre-synthesis database including a number of logical equations, and a post-synthesis database including at least the number of instances, wherein a synthesis tool implements the logical equations of the pre-synthesis database thereby resulting in at least the number of instances in the post-synthesis database.

5. A method according to claim 4 wherein a selected logical equation of the pre-synthesis database implements a vectored datapath function, and wherein the synthesis tool implements the selected logical equation using a number of selected instances.

6. A method according to claim 5 wherein said synthesis tool assigns instance names to the selected instances, such that the instance names identify each of the selected instances as corresponding to the stack.

7. A method according to claim 6 wherein the instance names assigned by the synthesis tool include a prefix portion and a suffix portion, wherein the prefix portion of the instance names identify each of the selected instances as corresponding to the stack.

8. A method according to claim 7 wherein the suffix portion of the instance names identifies a bit position of the corresponding instance within the vectored datapath function.

9. A method according to claim 8 wherein said selecting step includes the step of selecting any one of the instances corresponding to the stack, thereby resulting in a selected one of the number of instances.

10. A method according to claim 9 wherein the selected one of the number of instances has a selected bit position, and wherein predetermined ones of the instances have a bit position that is higher than the selected bit position and predetermined ones of the instances have a bit position that is lower than the selected bit position.

11. A method according to claim 10 wherein said selecting step further includes automatically selecting those instances having a bit position that is equal to or higher than the selected bit position.

12. A method according to claim 10 wherein said selecting step further includes automatically selecting those instances having a bit position that is equal to or lower than the selected bit position.

13. A method according to claim 1 wherein said selecting step includes the step of selecting any one of the instances corresponding to the stack.

14. A method according to claim 1 wherein the group operation includes a placing operation, wherein the placing operation places the selected instances at a desired location.

15. A method according to claim 14 wherein the placing operation includes the steps of:

a. selecting a first one of the number of selected instances;

b. placing the first one of the selected instances at a first desired location;

c. specifying a placement direction;

d. autoplacing the remainder of the selected instances extending from the first one of the number of selected instances, with a predetermined spacing therebetween, and in the placement direction.

16. A method according to claim 15 wherein said autoplacing step is initiated by depressing a predefined hot key.

17. A method according to claim 15 further comprising the step of specifying the predetermined spacing.

18. A method according to claim 1 wherein the group operation includes un-placing the selected instances.

19. A method according to claim 1 wherein the group operation includes moving the selected instances from a first location to a second location.

20. A method according to claim 1 wherein the group operation includes abutting the selected instances with one-another.

21. A method according to claim 1 wherein the group operation includes re-drawing the selected instances on a display device.

22. A method according to claim 1 wherein the group operation includes aligning the selected instances with a selected object in the circuit design database.

23. A method according to claim 1 wherein the group operation includes mirroring the selected instances about a predetermined axis.

24. A data processing system for selectively associating a number of instances of a circuit design database, comprising:

a. an associating block for associating a number of instances with a predefined instance grouping called a stack by associating a selected stack identifier with each of the number of instances, wherein the selected stack identifier is stored in the circuit design database, and identifies each of the number of instances as corresponding to the stack;

b. a selecting block coupled for selecting selected ones of the instances that correspond to the stack; and

c. a performing block coupled to said selecting block for performing a selected group operation on selected ones of the instances that correspond to the stack.

25. A data processing system according to claim 24 wherein each of the number of instances has a corresponding instance name associated therewith, wherein each of the number of instance names are stored in the circuit design database.

26. A data processing system according to claim 25 wherein said selected stack identifier for each of the number of instances is a selected portion of the corresponding instance name, wherein the selected portion of the instance name associates each of the number of instances with the stack.