Publication Type

Conference Proceeding Article

Version

publishedVersion

Publication Date

5-2026

Abstract

The principled combination of symbolic execution and random testing lacks a formal foundation, especially in deciding which inputs to symbolize. We propose selective concolic testing, a cost-aware framework that formulates this choice as an optimized policy problem of a MDP (Markov Decision Process). We model program exploration over a finite control-flow graph, where MDP states represent covered statements, actions partition path constraints into symbolic and random fragments, rewards reflect coverage gain, and costs account for SMT solving effort and sampling inefficiency. Our framework yields the first formal characterization of selective symbolization as policy synthesis in a probabilistic system. We prove that exact policy computation is intractable due to the exponential state space and the hardness of solution-density estimation via model counting. Our formulation enables a practical approximation: we partition constraint dependency graphs and use machine learning to predict solver timeouts, guiding per-constraint symbolization decisions. Built on top of KLEE and JFS, our prototype validates the approach on real-world floating-point benchmarks. Results show that selectively symbolizing inputs, guided by predicted solvability and cost, significantly improves coverage efficiency. Our work thus provides both a rigorous theoretical foundation and a practical instantiation for hybrid program analysis.

Keywords

Concolic Testing, Symbolic Execution, MDP, Constraint Solving

Discipline

Artificial Intelligence and Robotics | Software Engineering

Research Areas

Software and Cyber-Physical Systems

Areas of Excellence

Digital transformation

Publication

Proceedings of the 27th International Symposium, FM 2026, Tokyo, Japan, May 18-22

First Page

275

Last Page

295

ISBN

9783032262196

Identifier

10.1007/978-3-032-26220-2_14

Publisher

Springer

City or Country

Cham

Additional URL

https://doi.org/10.1007/978-3-032-26220-2_14

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