Improving the analysis precision of JavaScript programs via assertion

Abstract

In this paper, we introduce both an analysis framework for JavaScript, SAFE and a method to improve the analysis precision of JavaScript programs using the framework. Especially, we focus on conditional branches in the control flow graph level intermediate language. Because control flow graph contains information for conditional branches, we can prune memory states depending on a conditional expression of each branch. Some conditional expressions can prune its memory state with sound, and get higher accuracy than without considering expressions of conditions. We obtain higher precision of the analysis and find unreachable code with our method.