Overview

X-Gen is a random test-case and system-level stimuli generation tool associated with IBM hardware verification work. It was initiated in 2000 to apply previously successful processor-verification technology at the system level. A 2002 reference describes it as “X-Gen: A random test-case generator for systems and socs.”

Architecture and modeling

X-Gen was designed with a knowledge-based architecture similar to Genesys PE and uses the same CSP solver. Its main difference from the processor-oriented tool is its modeling language: because X-Gen targets the system-level domain, components, system transactions, and configurations are first-class members of the language.

Evaluation and deployment

In 2002, X-Gen was evaluated by running it in parallel with a legacy, non-knowledge-based stimuli generator for systems. The reported result was that X-Gen achieved higher coverage metrics while using one-fifth of the simulation time and one-tenth of the test templates. This result positioned X-Gen as the primary stimuli generator for IBM high-end systems.

Since 2002, X-Gen has been used in verification of most IBM high-end system designs discussed in the source, including the p-Series server and Cell-processor-based systems.

Maintainability context

The surrounding application architecture described for these test-generation tools separates a generic generation engine from a knowledge base, enabling reuse of generator capabilities and generic testing knowledge across new designs. The same source describes a service-oriented maintenance model with separate responsibilities for knowledge engineers, tool developers, and core technology developers, plus staged delivery and periodic synchronization of sources.