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arXiv · 1403.3996

JSAI: Designing a Sound, Configurable, and Efficient Static Analyzer for JavaScript

Vineeth Kashyap·Kyle Dewey·Ethan A. Kuefner·John Wagner·Kevin Gibbons·John Sarracino·Ben Wiedermann·Ben Hardekopf
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Abstract

We describe JSAI, an abstract interpreter for JavaScript. JSAI uses novel abstract domains to compute a reduced product of type inference, pointer analysis, string analysis, integer and boolean constant propagation, and control-flow analysis. In addition, JSAI allows for analysis control-flow sensitivity (i.e., context-, path-, and heap-sensitivity) to be modularly configured without requiring any changes to the analysis implementation. JSAI is designed to be provably sound with respect to a specific concrete semantics for JavaScript, which has been extensively tested against existing production-quality JavaScript implementations. We provide a comprehensive evaluation of JSAI's performance and precision using an extensive benchmark suite. This benchmark suite includes real-world JavaScript applications, machine-generated JavaScript code via Emscripten, and browser addons. We use JSAI's configurability to evaluate a large number of analysis sensitivities (some well-known, some novel) and observe some surprising results. We believe that JSAI's configurability and its formal specifications position it as a useful research platform to experiment on novel sensitivities, abstract domains, and client analyses for JavaScript.

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Vineeth Kashyap, Kyle Dewey, Ethan A. Kuefner, John Wagner, Kevin Gibbons, John Sarracino, Ben Wiedermann, Ben Hardekopf. 2014-03-17. JSAI: Designing a Sound, Configurable, and Efficient Static Analyzer for JavaScript. https://arxiv.org/abs/1403.3996

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