arXiv subjects

Xutong Ma

Publications and source records attributed to Xutong Ma.

3 recordsLinked to original sources

arXiv2026

We Must Have Missed This Comment: Detecting and Repairing Stale Function References in Linux Kernel Comments

As the Linux kernel evolves, code comments may become outdated, as the functions they reference can be refactored or removed independently without corresponding updates to the comments. Such stale function references can mislead maintainers and thus hinder code comprehension. Prior work on detecting code-comment inconsistency mainly focused on addressing semantic misalignment between Javadoc comments and their directly annotated functions, making them inapplicable to this type of externally induced staleness in the Linux kernel. Therefore, we propose ReCite, a three-stage approach to identify and repair such stale references: (1) detecting unresolved function-form symbols -- symbols in comments that appear to reference functions but for which no matching function can be found in the current codebase, (2) tracing the evolution history of each unresolved symbol through the Git history, and (3) generating LLM-based repair suggestions grounded in the evolution history and current code context. On Linux kernel v6.18-rc1, ReCite detects 869 stale references with generated repair suggestions. A manual evaluation on 200 sampled repairs shows that 178 (89.0%) provide useful repair guidance, with 85 (42.5%) directly applicable. Of our 75 submitted patches, 50 have been accepted. We also empirically study all unresolved function-form symbols.

cs.SE↗

arXiv2025

An Empirical Study: MEMS as a Static Performance Metric

Static performance estimation is essential during compile-time analysis, yet traditional runtime-based methods are costly and platform-dependent. We investigate mems, the number of memory accesses, as a static and architecture-independent performance metric. We develop a Clang-based automated instrumentation tool that rewrites source code to insert path tracing and \textit{mems} counting logic. This allows us to evaluate mems-based performance estimation across ten classical algorithm programs. Experimental results show that within the same program, execution paths with higher mems values consistently exhibit longer runtime. However, this correlation weakens between different programs, suggesting that mems is best suited for comparing performance of different execution paths in a program.

cs.SE↗

arXiv2022

Improving Tese Case Generation for Python Native Libraries Through Constraints on Input Data Structures

Modern Python projects execute computational functions using native libraries and give Python interfaces to boost execution speed; hence, testing these libraries becomes critical to the project's robustness. One challenge is that existing approaches use coverage to guide generation, but native libraries run as black boxes to Python code with no execution information. Another is that dynamic binary instrumentation reduces testing performance as it needs to monitor both native libraries and the Python virtual machine. To address these challenges, in this paper, we propose an automated test case generation approach that works at the Python code layer. Our insight is that many path conditions in native libraries are for processing input data structures through interacting with the VM. In our approach, we instrument the Python Interpreter to monitor the interactions between native libraries and VM, derive constraints on the structures, and then use the constraints to guide test case generation. We implement our approach in a tool named PyCing and apply it to six widely-used Python projects. The experimental results reveal that with the structure constraint guidance, PyCing can cover more execution paths than existing test cases and state-of-the-art tools. Also, with the checkers in the testing framework Pytest, PyCing can identify segmentation faults in 10 Python interfaces and memory leaks in 9. Our instrumentation strategy also has an acceptable influence on testing efficiency.

cs.SE↗