Computing must and may alias to detect null pointer dereference

Abstract

This paper presents a novel algorithm to detect null pointer dereference errors. The algorithm utilizes both of the must and may alias information in a compact way to improve the precision of the detection. Using may alias information obtained by a fast flow- and context- insensitive analysis algorithm, we compute the must alias generated by the assignment statements and the must alias information is also used to improve the precision of the may alias. We can strong update more expressions using the must alias information, which will reduce the false positives of the detection for null pointer dereference. We have implemented our algorithm in the SUIF2 compiler infrastructure and the experiments results are as expected. © 2008 Springer-Verlag.