New Accellera Committee proposed for Graph-Based Test Specification Standard

March 07, 2014 // By Graham Prophet
Mentor Graphics recently announced it has proposed that a new Accellera standards committee be formed to investigate the standardisation of a graph-based test specification standard. To underscore this endeavor, Mentor will make a technical donation of its existing graph-based test specification format to jump-start the standardisation effort.

The benefits of graph-based test specification, Mentor says, are threefold. First, it reduces the time spent writing and debugging tests by 50% or more. Verification engineers can use the graph-based specification format to describe the exact same test universes currently described in their existing SystemVerilog UVM constraint-based tests, in less than half the lines of code, without any change to the test intent. This also means a reduction in the number of test bugs, enabling verification engineers to focus on debugging their designs, not their tests.

Second, the graph-based test specification format naturally supports multiple design languages and multiple verification environments enabling re-use across both design context and verification engines. The same graph-based test specification can be used in a SystemVerilog UVM testbench environment for block-level simulation, as well as in an embedded C test program for system-level emulation. It can also be used to generate instructions for microprocessor instruction set verification, and it can even be used on target hardware including FPGA prototyping and post-silicon validation.

Third, the abstract nature of a graph-based test specification lets tool implementations execute the test specification in different ways according to verification requirements. For example, a tool with a graph-based test specification can be instructed to execute the test specification in a systematic way to quickly achieve functional coverage during the early stages of a verification project. At a later time, the tool can be instructed to execute the test specification in a completely random manner to produce soak tests on a simulation farm for regression testing.

“We have seen customers realise a ten-fold gain in productivity through the adoption of graph-based test technology,” said John Lenyo, vice president and general manager, Design Verification Technology Division, Mentor Graphics. “Based on customer feedback, we’re moving forward to recommend and facilitate a standards effort that brings significant benefits to a large number of users, and opens the door to technology innovation.”

The graph-based specification