VP_TT: A value propagation based equivalence checker for testability transformations

Abstract Testability transformation (TT) is a source‐to‐source programme transformation that aims to improve the ability of a given test generation method to generate test data for the original programme. Herein, the correctness of testability transformations is shown. Translation validation is the process of proving that the transformed programme is a correct translation of the source programme being compiled. It is widely used to verify the correctness of various compiler optimizations and transformations during scheduling. The value propagation based equivalence checking (VP) method is an efficient translation validation approach proposed to verify the correctness of various compiler optimization applied during scheduling in high‐level synthesis. VP‐based translation validation of testability transformations is proposed. In particular, it is identified that the existing VP method fails to show the equivalence for some of the TTs. A dynamic cutpoint selection scheme and an enhancement to the VP method to overcome these limitations are shown. The enhanced VP method, called VP_TT, successfully shows the equivalence for the TTs where the VP method fails. Experimental results confirm the usefulness of VP_TT in the verification of testability transformations