Observerability Analysis of HDL Designs Based on CLP Model

Traditional RTL test generation algorithms mainly focus on exciting a specific type of error,but consider little about the observability of errors．In this paper,we address the problem of observability analysis for assignment statements in RTL designs．The conditions of observing a variable are described as deduction rules,considering both control and data flow．Based on these deduction rules,constrain logic programming system will complete path searching and constraints solving automatically．This method can not only detect error in a specific statement,but also find function irrelevant code．The experimental results show that tests generated by our method can improve the observability-based code and branch coverage and speed up the error detection with little overhead．