SURGE: On the Potential of Large Language Models as General-Purpose
  Surrogate Code Executors
Authors: name: Bohan Lyu; name: Siqiao Huang; name: Zichen Liang
Published: 2025-02-16 15:38:19

Abstract: Large language models (LLMs) have demonstrated remarkable capabilities in
code-related tasks, such as code understanding and code generation. However, an
equally important yet underexplored question is whether LLMs can serve as
general-purpose surrogate code executors, to predict the output and behavior of
a program without actually running it. To systematically investigate this
capability, we introduce SURGE, a comprehensive benchmark covering eight key
aspects: multi-language programming tasks, competition-level programming
problems, repository-level code analysis, high-cost scientific computing,
time-complexity-intensive algorithms, buggy code analysis, programs dependent
on specific compilers or execution environments, and formal mathematical proof
verification. We evaluate multiple open-source and proprietary LLMs on SURGE
and conduct a scaling study to analyze the impact of model size and training
data scale on surrogate execution accuracy. Additionally, we categorize model
prediction errors and explore potential areas for improvement. Our findings
indicate that while LLMs can predict code execution results in certain cases,
they exhibit limitations in general-purpose surrogate execution. This study
provides empirical insights into the feasibility of using LLMs as surrogate
code executors. Code and dataset are released at
https://github.com/Imbernoulli/SURGE.