International Business Machines Corporation

Tzach Schechner

Roy Emek

Itai Jaeger

Allon Adir

Sanjay Gupta

Todd Swanson

Eitan Marcus

Lawrence Allyn McConville

Igor Dozorets

A computer software product is provided. The product includes a computer-readable medium in which computer program instructions are stored, which instructions, when read by a computer, cause the computer to perform a method for functional verification of a design, having an operational space comprising the steps of accepting as an input a test template that specifies test parameters directed to a function of the design, the template comprising constraints and variables covering a working space within the operational space, associating an exemption mode of operation with at least one of the constraints or at least one of the variables, wherein a domain of the at least one of the variables is modified or the at least one of the constraints is disabled in the exemption mode of operation, producing a test case that lies in the operational space of the design by enabling the exemption mode of operation, the test case comprising a series of transactions originating from the template, wherein the transactions exercise the function of the design, wherein the working space is modified in the exemption mode of operation and submitting the test case for execution by the design, wherein the exemption mode of operation is associated with only a portion of the template.

Highly specialized scenarios in random test generation

The input for a test generator is a plurality of test templates, each of which typically aims at covering a specific verification task. Test templates direct the production of distinct transactions, which are the atomic functional building blocks of the design-under-verification. Test templates directed to different hardware functions of the scenario are dynamically interleaved. In this way several transactions are combined together in complex statements in order to achieve a complex test scenario. The transactions are submitted to the test generator, which generates test cases, in which the different hardware functions of the scenario are exercised in combinations. Variation among the test cases is achieved through a large number of random decisions made during the generation process.

Dynamically interleaving randomly generated test-cases for functional verification

Improvements in functional verification of a design are achieved by providing a test template that specifies test parameters directed to a function of the design. An exemption mode of operation is associated with a portion of the template, in which constraints and variables associated with the template are revised. The template is an input to a CSP engine, which, in cooperation with a test generator engine, produces test scenarios that lie in an expanded region of the generator's usual operational space. Provision is made for independently enabling and disabling a plurality of exemption modes of operation that are associated with the same or different areas of the template.

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Tel Aviv, Israel

Tzach Schechner