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Cost-Aware Automatic Program Repair [article]

Roopsha Samanta, Oswaldo Olivo, E. Allen Emerson
2014 arXiv   pre-print
We present a formal framework for repairing infinite-state, imperative, sequential programs, with (possibly recursive) procedures and multiple assertions; the framework can generate repaired programs by modifying the original erroneous program in multiple program locations, and can ensure the readability of the repaired program using user-defined expression templates; the framework also generates a set of inductive assertions that serve as a proof of correctness of the repaired program. As a
more » ... p toward integrating programmer intent and intuition in automated program repair, we present a " cost-aware" formulation - given a cost function associated with permissible statement modifications, the goal is to ensure that the total program modification cost does not exceed a given repair budget. As part of our predicate abstraction-based solution framework, we present a sound and complete algorithm for repair of Boolean programs. We have developed a prototype tool based on SMT solving and used it successfully to repair diverse errors in benchmark C programs.
arXiv:1307.7281v2 fatcat:k2dqjlfltrfuflem4dytluqsau

Cost-Aware Automatic Program Repair [chapter]

Roopsha Samanta, Oswaldo Olivo, E. Allen Emerson
2014 Lecture Notes in Computer Science  
We present a formal framework for repairing infinite-state, imperative, sequential programs, with (possibly recursive) procedures and multiple assertions; the framework can generate repaired programs by modifying the original erroneous program in multiple program locations, and can ensure the readability of the repaired program using user-defined expression templates; the framework also generates a set of inductive assertions that serve as a proof of correctness of the repaired program. As a
more » ... p toward integrating programmer intent and intuition in automated program repair, we present a cost-aware formulationgiven a cost function associated with permissible statement modifications, the goal is to ensure that the total program modification cost does not exceed a given repair budget. As part of our predicate abstractionbased solution framework, we present a sound and complete algorithm for repair of Boolean programs. We have developed a prototype tool based on SMT solving and used it successfully to repair diverse errors in benchmark C programs.
doi:10.1007/978-3-319-10936-7_17 fatcat:ueyileksijh33hcppchfmqkysi

Static detection of asymptotic performance bugs in collection traversals

Oswaldo Olivo, Isil Dillig, Calvin Lin
2015 SIGPLAN notices  
This paper identifies and formalizes a prevalent class of asymptotic performance bugs called redundant traversal bugs and presents a novel static analysis for automatically detecting them. We evaluate our technique by implementing it in a tool called CLARITY and applying it to widely-used software packages such as the Google Core Collections Library, the Apache Common Collections, and the Apache Ant build tool. Across 1.6M lines of Java code, CLAR-ITY finds 92 instances of redundant traversal
more » ... gs, including 72 that have never been previously reported, with just 5 false positives. To evaluate the performance impact of these bugs, we manually repair these programs and find that for an input size of 50,000, all repaired programs are at least 2.45× faster than their original code. • First, it is difficult to know whether a program's performance can be expected to improve, since it depends on user inputs, on the many details of the program's execution environment, and on some notion of how a "good" solution should perform.
doi:10.1145/2813885.2737966 fatcat:a73f7fpxjbcfhcqzal4nuiz33e

Static Detection of DoS Vulnerabilities in Programs that use Regular Expressions (Extended Version) [article]

Valentin Wüstholz and Oswaldo Olivo and Marijn J. H. Heule and Isil Dillig
2017 arXiv   pre-print
[16] statically detect attackercontrolled loop bounds, and Olivo et al.  ... 
arXiv:1701.04045v1 fatcat:qxkjpioepjc3hga32jtmbihbuq

Síndrome hemofagocítico asociado con hepatitis

Eunice Sandoval-Ramírez, Ignacio Camacho-Meza, Nery Eduardo-Solís, Oswaldo Plascencia-Tabares, Efraín Navarro-Olivos, Francisco Ignacio Ortiz-Aldana
2016 Revista Alergia México  
El síndrome hemofagocítico se caracteriza por la proliferación y activación de células presentadoras de antígeno en médula ósea y otros órganos del sistema retículo endotelial, así como de linfocitos T CD8+ que pone en peligro la vida de los pacientes. Las manifestaciones clínicas predominantes como fiebre, citopenias, hepatitis, coagulopatía, síntomas neurológicos y falla orgánica múltiple están relacionadas con inflamación sistémica. Presentamos el caso de un lactante que inicia padecimiento
more » ... on ictericia, dolor abdominal, vomito, ataque al estado general, hepatomegalia, esplenomegalia y bioquímicamente con características sugestivas de inflamación hepatocelular y colestasis progresiva con mala evolución clínica, se agrega al cuadro fiebre persistente, crisis convulsivas, anemia, trombocitopenia, leucopenia, ferritina y triglicéridos elevados, integrando síndrome hemofagocítico con desenlace fatal a pesar de inicio de tratamiento inmunosupresor.
doi:10.29262/ram.v63i1.133 pmid:26943833 fatcat:y2bjbg7czzgazj2bfehppxwlq4

Static Detection of DoS Vulnerabilities in Programs that Use Regular Expressions [chapter]

Valentin Wüstholz, Oswaldo Olivo, Marijn J. H. Heule, Isil Dillig
2017 Lecture Notes in Computer Science  
[16] statically detect attackercontrolled loop bounds, and Olivo et al.  ... 
doi:10.1007/978-3-662-54580-5_1 fatcat:f6lyqx7swzhnboafwutp35xdgq

Studying the influence of standard compiler optimizations on symbolic execution

Shiyu Dong, Oswaldo Olivo, Lingming Zhang, Sarfraz Khurshid
2015 2015 IEEE 26th International Symposium on Software Reliability Engineering (ISSRE)  
Systematic testing plays a vital role in increasing software reliability. A particularly effective and popular approach for systematic testing is symbolic execution, which analyzes a large number of program behaviors using symbolic inputs. Even though symbolic execution is among the most studied analyses during the last decade, scaling it to real-world applications remains a key challenge. This paper studies how a class of semantics-preserving program transformations, namely compiler
more » ... ns, which are designed to enhance performance of standard program execution (using concrete inputs), influence traditional symbolic execution. As an enabling technology, the study uses KLEE, a well-known symbolic execution engine based on the LLVM compiler infrastructure, and focuses on 33 optimization flags of LLVM. Our specific research questions include: (1) how different optimizations influence the performance of symbolic execution for Unix Coreutils, (2) how the influence varies across two different program classes, and (3) how the influence varies across three different back-end constraint solvers. Some of our findings surprised us. For example, applying the 33 optimizations in a pre-defined order provides a slowdown (compared to applying no optimization) for a majority of the Coreutils when using the basic depth-first search with no constraint caching. The key finding of our work is that standard compiler optimizations need to be used with care when performing symbolic execution for creating tests that provide high code coverage. We hope our study motivates future research on harnessing the power of symbolic execution more effectively for enhancing software reliability, e.g., by designing program transformations specifically to scale symbolic execution or by studying broader classes of traditional compiler optimizations in the context of different search heuristics, memoization, and other strategies employed by modern symbolic execution tools.
doi:10.1109/issre.2015.7381814 dblp:conf/issre/DongOZK15 fatcat:vopgbbxbrfe3vkfpggbie6nu2y

A Unified Formal Framework for Analyzing Functional and Speed-path Properties

Oswaldo Olivo, Sandip Ray, Jayanta Bhadra, Vivekananda Vedula
2011 2011 12th International Workshop on Microprocessor Test and Verification  
We develop a formal tool for speed-path analysis and debug. We encode speed-path requirements in a formal hardware description language providing the semantics of both the functional behavior and timing constraints, and the disciplined use of an SMT solver to analyze speed-path requirements. We are applying our framework for speed-path analysis of several RTL designs from Opencores.
doi:10.1109/mtv.2011.17 dblp:conf/mtv/OlivoRBV11 fatcat:5upqedckezfdvh2dogjkwquoiu

Detecting and Exploiting Second Order Denial-of-Service Vulnerabilities in Web Applications

Oswaldo Olivo, Isil Dillig, Calvin Lin
2015 Proceedings of the 22nd ACM SIGSAC Conference on Computer and Communications Security - CCS '15  
This paper describes a new class of denial-of-service (DoS) attack, which we refer to as Second Order DoS attacks. These attacks consist of two phases, one that pollutes a database with junk entries and another that performs a costly operation on these entries to cause resource exhaustion. The main contribution of this paper is a static analysis for detecting second-order DoS vulnerabilities in web applications. We have implemented our analysis in a tool called Torpedo, and we show that Torpedo
more » ... can successfully detect second-order DoS vulnerabilities in widely used web applications written in PHP. Once our tool discovers a vulnerability, it also performs symbolic execution to generate candidate attack vectors. We evaluate Torpedo on six widely-used web applications and show that it uncovers 37 security vulnerabilities, while reporting 18 false positives.
doi:10.1145/2810103.2813680 dblp:conf/ccs/OlivoDL15 fatcat:6ualke5awberlnokteo4bgqvmm

Static detection of asymptotic performance bugs in collection traversals

Oswaldo Olivo, Isil Dillig, Calvin Lin
2015 Proceedings of the 36th ACM SIGPLAN Conference on Programming Language Design and Implementation - PLDI 2015  
This paper identifies and formalizes a prevalent class of asymptotic performance bugs called redundant traversal bugs and presents a novel static analysis for automatically detecting them. We evaluate our technique by implementing it in a tool called CLARITY and applying it to widely-used software packages such as the Google Core Collections Library, the Apache Common Collections, and the Apache Ant build tool. Across 1.6M lines of Java code, CLAR-ITY finds 92 instances of redundant traversal
more » ... gs, including 72 that have never been previously reported, with just 5 false positives. To evaluate the performance impact of these bugs, we manually repair these programs and find that for an input size of 50,000, all repaired programs are at least 2.45× faster than their original code. • First, it is difficult to know whether a program's performance can be expected to improve, since it depends on user inputs, on the many details of the program's execution environment, and on some notion of how a "good" solution should perform.
doi:10.1145/2737924.2737966 dblp:conf/pldi/OlivoDL15 fatcat:t3gjazazhfa73ej6jgzgrfiuve

Automatic static analysis of software performance [article]

Oswaldo Luis Olivo
2016
Olivo, I. Dillig, C. Lin.  ...  Olivo, I. Dillig, C. Lin. Static Detection of Asymptotic Performance Bugs in Collection Traversals. 36th ACM SIGPLAN Conference on Programming Language Design and Implementation (PLDI '15).  ... 
doi:10.15781/t2j96099s fatcat:qhckdor6rngmxaofyu5ny5z7ga

Reviewers of Volume 11, 2016 of Revista Ambiente & Água

Getulio Teixeira Batista
2016 Revista Ambiente & Água  
Brasil Toshio Nishijima Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brasil Tulio Assunção Pires Ribeiro Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brasil Valdir Eduardo Olivo  ...  Ramalho Universidade Federal de Lavras (UFLA), Lavras, MG, Brasil Tereza Cristina Favre Fundação Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ, Brasil Teresa Maria Reyna Universidad Nacional de Córdoba, Córdoba  ... 
doi:10.4136/ambi-agua.1873 fatcat:7fr52b2ibbfixkkw6pyuhfbt7m

Optimizing off-chip accesses in multicores

Wei Ding, Xulong Tang, Mahmut Kandemir, Yuanrui Zhang, Emre Kultursay
2015 Proceedings of the 36th ACM SIGPLAN Conference on Programming Language Design and Implementation - PLDI 2015  
Oswaldo Olivo, Isil Dilling, and Calvin Lin.  ... 
doi:10.1145/2737924.2737989 dblp:conf/pldi/DingTKZK15 fatcat:5d6bhh2qovaevaku4qmnacnz74

Associação paulista de medicina secção de neuro-psiquiatria

1945 Arquivos de Neuro-Psiquiatria  
Oswaldo Lange. Êste trabalho será publicado, na íntegra, no próximo número desta revista. Abscesso cerebral de sintomatologia atípica simulando hematoma. Cura cirúrgica (Com apresentação do doente).  ...  mioclonias atingirão músculos esqueléticos ou serão velolaringo-faringo-diafragmáticas conforme a lesão se assente na porção hilar do núcleo denteado ou sua vertente periférica, onde chegam as fibras olivo-denteadas  ... 
doi:10.1590/s0004-282x1945000200017 fatcat:jenei4fawbespjkt6cy6yprj24

Optimizing off-chip accesses in multicores

Wei Ding, Xulong Tang, Mahmut Kandemir, Yuanrui Zhang, Emre Kultursay
2015 SIGPLAN notices  
Oswaldo Olivo, Isil Dilling, and Calvin Lin.  ... 
doi:10.1145/2813885.2737989 fatcat:jqbls2ejwrc6vbxu2p6kfg6may
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