Method and system for automatically creating tests

• US 7,665,067 B2
• Filed: 09/15/2003
• Issued: 02/16/2010
• Est. Priority Date: 09/15/2003
• Status: Active Grant

• Current Assignee: Cadence Design (Israel) II Ltd. (Cadence Group)
• Original Assignee: Cadence Design (Israel) II Ltd. (Cadence Group)
• Inventors: Hollander, Yoav, Kashai, Yaron
• Primary Examiner(s): WANG, RONGFA PHILIP
• Application Number:
  US10/661,772
• Publication Number:
  US 20050060132A1
• Time in Patent Office: 2,346 Days
• Field of Search: 717124-131, 717148-149, 710/100
• US Class Current: 717/124
• CPC Class Codes: G01R 31/318307 computer-aided, e.g. automatic test program generator [ATPG], program translations, test program debugging
• CPC Class Codes: G01R 31/318357 Simulation computer simulation of digital circuits G06F30/3308
• CPC Class Codes: G06F 30/33 Design verification, e.g. functional simulation or model checking

Abstract

A system and method for generalized scenarios, for automatically generating tests. The tests are generated from some underlying structure, such as one or more scenarios. The scenarios preferably include a plurality of constraints for generating a test program for generating input values to the test generation process. The scenarios provide a more generalized method for generating tests.

Claims

1. A method stored on a computer readable medium including computer executable instructions for automatically generating at least one test program from a set of scenarios for testing a simulation model of a device under test (DUT) in a test environment during a test verification process, the method comprising:

providing a plurality of scenarios, each scenario containing at least one operation and at least one constraint indicative of which other scenarios may be compatible therewith for the test program;

selectively defining a set of scenarios from said plurality of scenarios according to said constraints thereof by resolving conflicts among said constraints, said set of scenarios excluding conflicting scenarios; and

automatically generating the test program by combining said set of scenarios to provide at least one operation as input for driving simulated operation of the DUT.

2. The method of claim 1, wherein said selectively defining a set of scenarios comprises:

selecting a number of said plurality of scenarios according to meta-data contained in at least one scenario; and

combining said number of said plurality of scenarios to form a combined scenario instance.

3. The method of claim 2, wherein at least one selected scenario comprises a sequence.

4. The method of claim 3, wherein at least one selected scenario conflicts with at least one non-selected scenario and wherein said meta-data comprises information about said conflict.

5. The method of claim 1, wherein said selecting at least one of said plurality of scenarios is performed at least partially according to a configuration of the DUT.

6. The method of claim 1, wherein said providing said scenarios is performed during a scenario creation process.

7. The method of claim 6, wherein a user performs said scenario creation process.

8. The method of claim 1, wherein said providing said plurality of scenarios is performed by a user.

9. The method of claim 1, further comprising:

generating at least one external file according to said at least one scenario.

10. The method of claim 9, further comprising:

using said at least one external file at run time for running the test.

11. The method of claim 10 further comprising:

compiling said at least one external file before said using said at least one external file.

12. The method of claim 10, wherein said generating said at least one external file is performed before or concurrently with said generating said test.

13. The method of claim 10, wherein said external file comprises an HDL (hardware description language) file for configuring the simulation model.

14. The method of claim 1, wherein said generating the test is performed according to an at least partially randomized process.

15. The method of claim 14, wherein said randomized process is based upon a plurality of constraints, and wherein said plurality of constraints is provided in said selected scenario.

16. The method of claim 1, wherein said generating the test is performed according to said at least one constraint.

17. The method of claim 16, wherein each constraint defines a type of expected input variable and a type of operation to be performed on said type of expected input variable.

18. The method of claim 17, wherein said constraint comprises a static constraint on a value of said type of expected input variable.

19. The method of claim 17, wherein said constraint comprises a dynamic constraint on a value of said type of expected input variable.

20. The method of claim 17, wherein said at least one type of expected input variable is at least partially determined according to a simulation model of the DUT.

21. The method of claim 1, wherein at least one characteristic of said constraint determines whether said constraint conflicts with another constraint.

22. The method of claim 1, wherein the simulation model comprises a plurality of variables, wherein at least one scenario comprises a monitoring operation for monitoring behavior of the simulation model and wherein said monitoring operation comprises sampling at least one value of at least one variable of the simulation model.

23. The method of claim 1, wherein the selectively defining a set of scenarios from said plurality of scenarios according to said at least one constraint is accomplished by automatically selecting a subset of said plurality of scenarios by resolving said constraints of said plurality of scenarios to include in the selected subset only non-conflicting scenarios.