Yingfei Xiong

Associate Professor with Tenure
Co-Appointed Research Professor
Programming Languages Lab (Vice Director)
Institute of Software （Vice Director)
School of Computer Science
Peking University

Distinguished Member of ACM, Member of IFIP WG 2.4, IEEE, CCF

Office: Room 1431, Science Building # 1, Yanyuan Campus / 447 Wende Building, Changping New Campus
Email: xiongyf@pku.edu.cn
Tel: +86-10-62757008-12

Pronunciation of my name: [i:ŋfei] (yingfei) [ʃiɔŋ] (xiong)

中文版

News (More)

September 30, 2025 We upgraded our probabilistic fault localization approach, SmartFL, with a new general probabilistic inference algorithm and new techniques enhancing the scalability. Being training-free, SmartFL outperforms existing training-free approaches (e.g., SBFL and MBFL) in terms of not only effectiveness but also efficiency, and has the SOTA performance in statement-level fault localization in Defects4J. A TSE paper describes the udpated SmartFL approach, and an ASE'25 paper describes the new probabilistic inference algorithm.
August 24, 2025 Tunneling Through the Hill: Multi-Way Intersection for Version-Space Algebras in Program Synthesis was accepted at OOPSLA. In this paper, we propose a new way to efficiently perform intersection, a basic operation in VSA-based program synthesis.
July 30, 2025 Through a collaboration project with ByteDance, we contributed to the development of Trae Agent, the currently best-performing code agent in SWE-Bench Verified, by proposing a summarization technique for agent trajectories.
May 10, 2025 Grammar-Based Code Representation: Is It a Worthy Pursuit for LLMs? was accepted at ACL as a finding. In this paper, we evaluate whether our grammar-based code representation is still useful in large neural models. We found that though large models seldom make syntax errors, their performance still significantly improves when using grammar-based representation, because grammar-based representation has better correspondance to the semantics of code.
February 20, 2025 I was selected as an ACM Distinguished Member for my contributions to program repair and synthesis.

Education & Employment

04/2012~07/2018, Peking University, Research Professor in Young Talents Plan (Tenure-Track Assistant Professor Equivalence)
12/2009~11/2011, University of Waterloo, PostDoc. Advisor: Krzysztof Czarnecki
10/2006~09/2009, The University of Tokyo, Ph.D. Advisors: Zhenjiang Hu Masato Takeichi
09/2004~09/2006, Peking University, Pre-Ph.D. Course. Advisors: Hong Mei Fuqing Yang
09/2000~06/2004, University of Electronic Science and Technology of China, Bachelor Diploma of Computer Science

Current Research Projects

Algorithm Synthesis

Benchmark: [FSE24DEMO]
Synthesis: [PLDI24][TOPLAS24][OOPSLA23b]
Verification: [FM24]

Program Repair / Synthesis
- Perspective & Empirical Studies: [SCIS19a][SCIS19b]
- Defining a search space: [FSE21b][ASE19a][ISSTA18a][ASE15]
- Locating likely elements in a space: [OOPSLA23a][TOSEM22][OOPSLA21][OOPSLA20][GI18][ICSE18a][ICSE17a]
- Interaction: [ICSME21][PLDI20][ISSRE19]
- Validation & Patch Generation: [TSE24][ASE23Demo][ASE21][ISSTA17][Interwa17]
- Specific Bug Types: [ASE23][ICSE15a]
Fault Localization: [ICSE22a][FSE21a][TSE19][ASE19c]
Efficient Program Analysis: [ASE21][SAS21][IJCAI20][ESOP17][ISSTA17]
Analyzing Floating-Point and Deep Learning Programs: [ICSE23b][FSE20][OOPSLA22][POPL20][ISSTA18b][FSE16][ICSE15b][ASE14]

Recent Selected Publications

[Complete List | Invited Talks | DBLP | Google Scholar]

[ASE25]	Yiqian Wu, Yifan Chen, Yingfei Xiong, Xin Zhang^. Belief Propagation with Local Structure and Its Applications in Program Analysis*. ASE25: 40th IEEE/ACM International Conference on Automated Software Engineering, November 2025.
[OOPSLA25]	Guanlin Chen^#, Ruyi Ji^#, Shuhao Zhang^#, Yingfei Xiong^. Tunneling Through the Hill: Multi-Way Intersection for Version-Space Algebras in Program Synthesis*. OOPSLA'25: the OOPSLA issue of the Proceedings of the ACM on Programming Languages, October 2025. [Paper]
[arXiv25]	Pengfei Gao^#, Zhao Tian^#, Xiangxin Meng, Xinchen Wang, Ruida Hu, Yuanan Xiao, Yizhou Liu, Zhao Zhang, Junjie Chen, Cuiyun Gao, Yun Lin, Yingfei Xiong, Chao Peng, Xia Liu. Trae Agent: An LLM-based Agent for Software Engineering with Test-time Scaling. arXiv:2507.23370, July 2025. [Paper]
[TSE25]	Yiqian Wu, Yujie Liu, Yi Yin, Muhan Zeng, Zhentao Ye, Xin Zhang^, Yingfei Xiong, Lu Zhang. SmartFL: Semantics Based Probabilistic Fault Localization*. IEEE Trans. Software Eng. 51(7): 2161-2180, July 2025. [Paper]
[ACL-Fnd25]	Qingyuan Liang, Zhao Zhang, Zeyu Sun^, Zheng Lin, Qi Luo, Yueyi Xiao, Yizhou Chen, Yuqun Zhang, Haotian Zhang, Lu Zhang, Bin Chen, Yingfei Xiong^. Grammar-Based Code Representation: Is It a Worthy Pursuit for LLMs?. ACL (Findings): Findings of the Association for Computational Linguistic, July 2025. [Paper]
[FSE24DEMO]	Zhao Zhang, Yican Sun, Ruyi Ji, Siyuan Li, Xuanyu Peng, Zhechong Huang, Sizhe Li, Tianran Zhu, Yingfei Xiong^. ASAC: A Benchmark for Algorithm Synthesis*. FSE'24-Demo: The ACM International Conference on the Foundations of Software Engineering, Tool Demonstration Track, September 2024. [Paper]
[FM24]	Yican Sun, Ruyi Ji, Jian Fang, Xuanlin Jiang, Mingshuai Chen, Yingfei Xiong^. Proving Functional Program Equivalence via Directed Lemma Synthesis*. FM'24: 26th International Symposium on Formal Methods, September 2024. [Paper]
[PLDI24]	Ruyi Ji, Yuwei Zhao, Nadia Polikarpova, Yingfei Xiong^, Zhenjiang Hu. Superfusion: Eliminating Intermediate Data Structures via Inductive Synthesis*. PLDI'24: ACM SIGPLAN Conference on Programming Language Design and Implementation, June 2024. [Paper][Online Demo]
[ICSE24]	Qihao Zhu, Qingyuan Liang, Zeyu Sun, Yingfei Xiong^, Lu Zhang, Shengyu Cheng. GrammarT5: Grammar-Integrated Pretrained Encoder-Decoder Neural Model for Code*. ICSE'24: 46th International Conference on Software Engineering, April 2024. [Paper]
[TSE24]	Yuanan Xiao, Chenyang Yang, Bo Wang, Yingfei Xiong^. Accelerating Patch Validation for Program Repair with Interception-Based Execution Scheduling*. TSE: IEEE Transactions on Software Engineering, Online First, January 2024. [Paper]

Teaching

Software Analysis: Fall 2025, Fall 2024, Fall 2023, Fall 2022, Fall 2021, Fall 2020, Fall 2019, Fall 2018, Fall 2017, Fall 2016, Fall 2015, Fall 2014
- Course Video of 2020
Software Foundations: Spring 2025, Spring 2024, Spring 2023, Spring 2022, Spring 2021
Design Principles of Programming Languages: Spring 2021, Spring 2020, Spring 2019, Spring 2018, Spring 2017, Spring 2016, Spring 2015, Spring 2014
Introduction to Computer Systems, Discussion Seminar: Fall 2019, Fall 2018, Fall 2017, Fall 2016, Fall 2015, Fall 2014, Fall 2013, Fall 2012
Algorithm Design and Analysis, Discussion Seminar: Spring 2014, Spring 2013

Academic and Department Service

2026, Selection Committee Member: SIGSOFT Summer/Winter School funding program
2026, Associate Chair: OOPSLA 2026
2025, PC Member: ASE 2025 Journal-First Track
2025, Area Chair: ASE 2025
2025, PC Member: ICSE 2026
2024, PC Member: LLM4Code 2025
2024, Mentor Chair: ICSE 2025 Shadow PC Track
2024, PC Member: SETTA 2024
2024, Track Co-Chair: The 9th National Conference on Formal Methods and Applications (FMAC) / Chinasoft Formal Methods and Applications Track
2024, Review Committee Member: OOPSLA 2024
More...

More About Me

Awards, Honors, and Grants
Students
My Free/Busy Information: [HTML] [ICS]
Past Research Projects
- Compiler Testing: [ASE19b][TSE18][ICSE17b][ICSE16][ICST16b][CSUR19][SCIS19c]
- Program Transformation for API migration: [ECOOP16][PEPM15][ICWS13]
- Configuration Error Repair: [TSE15][ICSE12][SPLC13]
- Delta-Based Bidirectional Transformation (Postdoctoral Period)
- Heterogeneous Data Synchronization in Software Engineering (Doctoral Period)
  - Beanbag: OCL-lik Language for On-Site Synchronization
  - SyncATL: Model Synchronization using ATL
- Aspect-Oriented Intermediate Language (Undergraduate Period)