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X-Gen: A Random Test-Case Generator for Systems and SoCs

Paper WIKI v1 · 5/26/2026

A 2002 HLDVT paper by Emek and colleagues describing X-Gen, IBM's system-level random stimuli generator for hardware verification. Available evidence identifies X-Gen as a knowledge-based generator using the same CSP solver as Genesys PE, with a domain-specific modeling language for components, system transactions, and configurations.

Overview

X-Gen: A Random Test-Case Generator for Systems and SoCs is a 2002 paper by R. Emek, I. Jaeger, Y. Naveh, G. Bergman, G. Aloni, Y. Katz, M. Farkash, I. Dozoretz, and A. Goldin. It appeared in the Seventh IEEE International High-Level Design Validation and Test Workshop (HLDVT-02), on pages 145–150.

The paper is cited as the publication associated with X-Gen, a project initiated in 2000 to apply random stimuli generation technology to system-level stimuli generation for hardware verification.

Technical context

The available evidence places X-Gen in IBM's constraint-based random stimuli generation work. X-Gen followed the successful use of similar technology for processor verification and was designed with a knowledge-based architecture similar to Genesys PE. It also used the same CSP solver.

The main architectural distinction described for X-Gen was its modeling language: because X-Gen targeted system-level verification, the language made components, system transactions, and configurations first-class elements.

Reported evaluation and deployment

In 2002, X-Gen was tested in parallel with a legacy, non-knowledge-based system stimuli generator. 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. The evidence states that, since 2002, X-Gen was used in verification of most IBM high-end system designs, including p-Series servers and Cell-processor-based systems.

Significance

Based on the cited evidence, X-Gen represents an application of knowledge-based, CSP-supported random test generation beyond processor-level verification and into system-level hardware verification. Its modeling language adapted the generation framework to system-level concepts such as configurations and transactions.

CITATIONS

6 sources
6 citations
[1] The paper was authored by R. Emek, I. Jaeger, Y. Naveh, G. Bergman, G. Aloni, Y. Katz, M. Farkash, I. Dozoretz, and A. Goldin, published in 2002, and appeared in HLDVT-02 on pages 145–150. [PDF] Constraint-Based Random Stimuli Generation for Hardware ... - AAAI
[2] X-Gen was initiated in 2000 with the goal of applying the technology to system-level stimuli generation. Constraint-Based Random Stimuli Generation for Hardware Verification
[3] X-Gen used a knowledge-based architecture similar to Genesys PE and used the same CSP solver. Constraint-Based Random Stimuli Generation for Hardware Verification
[4] X-Gen's modeling language treated components, system transactions, and configurations as first-class members. Constraint-Based Random Stimuli Generation for Hardware Verification
[5] A 2002 comparison with a legacy non-knowledge-based system stimuli generator found that X-Gen achieved higher coverage metrics in one-fifth of the simulation time and one-tenth of the test templates. Constraint-Based Random Stimuli Generation for Hardware Verification
[6] After the 2002 evaluation, X-Gen became the primary stimuli generator for IBM high-end systems and was used in verification of most high-end system designs, including p-Series server and Cell-processor-based systems. Constraint-Based Random Stimuli Generation for Hardware Verification