High Level Test Generation Using Software Testing Metrics

Mark W. Johnson

M.S. Thesis, Department of Electrical and Computer Engineering, Technical Report CRHC-95-06/UILU-ENG-95-2204, University of Illinois, February 1995.


Modern circuit design methods are moving away from schematic-based design to Hardware Description Languages (HDLs). In a language based design methodology, a high level description is created, the design is verified, and then the logic is created or synthesized. The high level behavioral description represents a new source of information about the circuit which may be useful in test generation. This thesis explores that possibility. This thesis borrows techniques used in software testing [1, 2, 3, 4, 5, 6] for high level test generation. Systems have been built for programming languages, such as C and Fortran, that will give structural coverages of software programs [7, 8], and that will automatically generate data to obtain such coverages [9, 10, 11]. Since an HDL high level description is basically a software program, these techniques could also be applied to an HDL description. The experiment presented generates a test suite that will satisfy a particular software structural testing criteria for the behavioral VHDL (Very High Speed Integrated Circuit HDL) [12] description and then uses PROOFS [13] to evaluate these vectors on the functionally equivalent logic level description. PROOFS grades the circuit on the number of stuck-at-faults detected. This fault coverage is then compared to test vectors generated by HITEC [14], a deterministic gate level test generator. In this way, we can see the correlation of tests generated from the gate level description and tests generated from the behavioral description of a circuit. This thesis is divided into six chapters. Chapter 2 presents an introduction to VHDL. Chapter 3 is a short discussion on software testing techniques. Chapter 4 provides the research and results. Chapter 5 is a discussion on the results. Chapter 6 gives concluding remarks.

Send any questions to liz@crhc.uiuc.edu