Pruning, Pushdown Exception-Flow Analysis

TL;DR

This paper introduces a precise, scalable static analysis framework for exception-flows in object-oriented languages, combining pushdown control-flow pruning and enhanced reachability techniques to improve accuracy over traditional methods.

Contribution

It presents a novel pushdown control-flow analysis for exceptions and integrates generalized abstract garbage collection with liveness analysis for better points-to precision.

Findings

Significantly improves analysis precision over traditional methods.

Maintains reasonable analysis time for large Java applications.

Effectively matches throwers to catchers for precise exception handling.

Abstract

Statically reasoning in the presence of exceptions and about the effects of exceptions is challenging: exception-flows are mutually determined by traditional control-flow and points-to analyses. We tackle the challenge of analyzing exception-flows from two angles. First, from the angle of pruning control-flows (both normal and exceptional), we derive a pushdown framework for an object-oriented language with full-featured exceptions. Unlike traditional analyses, it allows precise matching of throwers to catchers. Second, from the angle of pruning points-to information, we generalize abstract garbage collection to object-oriented programs and enhance it with liveness analysis. We then seamlessly weave the techniques into enhanced reachability computation, yielding highly precise exception-flow analysis, without becoming intractable, even for large applications. We evaluate our pruned, pushdown exception-flow analysis, comparing it with an established analysis on large scale standard Java benchmarks. The results show that our analysis significantly improves analysis precision over traditional analysis within a reasonable analysis time.