Flow Analysis on Intermediate Source Code for WCET Estimation of Compiler-Optimized Programs

In this research we have developed an algorithmic approach to convert source code clones to aspects. Code cloning is the process of duplicating code or creating replication of code fragments. In this work, we use an existing code-clone detection tool to identify code clones in a source code. Secondly, we design algorithms to convert the code clones into aspects and do aspect composition with the original source code. Thirdly, we implement a prototype based on the algorithms. Fourthly, we carry out a performance analysis on the aspects composed source code and our analysis shows that the aspect composed code performs as well as the original code and even better in terms of execution times.

Abstract: In terms of software, continuous of the software is the best quality assurance. Continuous development requires either the original developer to continue development, or the next generation of developers to take over the development. It has been noted that when the original developer has used a development paradigm in which the source code is kept open to all, highly motivated and competent developers will participate in development. This makes it easier for a project to survive. However, at the same time, when the source code is opened to a broad audience a in the source code tends to occur. When this happens, those with a high level of competence and motivation abandon the development and go their separate ways. In such a situation, it is difficult for a project to survive. In the case of Denshin 8 go, a guardian for the source code was appointed, and the original developer and the guardians avoided this dilemma. Richard Stallman of the GNU project and Linus Torvalds of Linux project act as legitimate guardians to avoid fork.Keywords: software development, open source, fork, buried source code, legitimate guardian, Denshin 8 goIntroductionFor software, continuous of the software is the best quality assurance (Ikuine 8s Fujita, 2013). Continuous development requires either the original developer to continue development or others to take over (Fujita 8s Ikuine, 2013b). When other developers take over, the original developer must share the source code with others. Open Source is a paradigm wherein the source code is shared and made broadly available to others. It has been noted that the project adopting open source can attract competent and highly motivated developers. Thus, some claim that developers can readily ensure the survival of software development projects when the source code is open.However, opening the source code to a broad audience can cause heterogeneity in the source code, even when people continue the development based on the original source code, a phenomenon known as fork (forking). In the case of open source software (hereinafter, OSS), literally anyone can obtain the source code and modify it to develop new software and start up new projects. Therefore, forks often occur in the OSS project, and the impact of forking has been studied for very long (Dibona, Ockman, 8s Stone, 1999; Kogut 8s Metiu, 2001; Nyman 8s Lindman, 2013; Nyman, Mikkonen, Lindman, 8s Fougere, 2012; Raymond, 1997, 1999). Moreover, some studies have focused on how to maintain forked projects, under the assumption that forking will inevitably occur (Gamalielesson 8s Lundell, 2013; Ray 8s Kim, 2012; Ray, Wiley, Kim, 2012).When forking does occur, competent and motivated developers start to abandon the project and go their separate ways, which may affect the survival of these projects. In other words, sharing the source code comes with a dilemma. If one loosens restrictions and shares the source code broadly, that project may survive; however, if the project is forked, competent successors with strong skills and desires will end up working on their own, or perhaps inter-project competition may lead to vying for competent successors. On the other hand, while establishing strict conditions and sharing the source code only with a select few may make the source code easy to control and reduce the possibility of forking, it may become more difficult to find competent successors willing to participate under those conditions. This puts the survival of the project at risk. Ensuring the survival of a project requires that one avoid this dilemma of source code sharing.Research on avoiding the has heretofore focused on developer motivation, licenses, and project governance (Ernst, Easterbrook, 8s Mylopoulos, 2010; Neville-Neil, 2011; Nyman 8s Mikkonen, 2011; Robles 8s Gonzalez-Barahona, 2012; Viseur, 2012). However, forking is a phenomenon not limited to OSS, and examples can be seen in Unix as well (Takahashi 8s Takamatsu, 2002, 2013). …

The lack of compatibility of High‐Performance Fortran (HPF) between vender implementations has been disheartening scientific application users so as to hinder the development of portable programs. Thus parallel computing is still unpopular in the computational science community, even though parallel programming is common to the computer science community. As users would like to run the same source code on parallel machines with different architectures as fast as possible, we have investigated the compatibility of source codes for Japanese HPF compilers (NEC, Fujitsu and Hitachi) with two real‐world applications: a 3D fluid code and a 2D particle code. We have found that the source‐level compatibility between Japanese HPF compilers is almost preserved, but more effort will be needed to sustain complete compatibility. We have also evaluated parallel performance and found that HPF can achieve good performance for the 3D fluid code with almost the same source code. For the 2D particle code, good results have also been obtained with a small number of processors, but some changes in the original source code and the addition of interface blocks is required. Copyright © 2002 John Wiley & Sons, Ltd.

소프트웨어 산업은 21세기 정보화 사회의 발전에 있어서도 중요한 역할을 하고 있다. 소프트웨어 소스 코드의 소유권 분쟁이 발생 시 소유권을 증명하기 위해서는 원본의 소프트웨어 소스코드를 판별해야만 하는 문제점을 갖고 있다. 본 논문에서는 소프트웨어 소스코드의 원본 판별을 지원하기 위한 소프트웨어 소스코드의 디지털 라이센스는 소스코드의 예약어를 파싱하여 계층구조를 갖는 XML 파일로 표현하며, 복잡한 소스코드 대신에 소프트웨어 소스코드의 노드 패턴과 아키텍처 패턴인 트리 구조 형태로 표현할 수 있다. 그리고 디지털 라이센스에 의한 소스코드의 분류 가능성에 대한 시뮬레이션과 크립텍스 모델을 제안한다. The software industry is so important to the 21C information society Not only the digital content control but the technology of software source code for the intellectual property is so much mean to international competition. On occurring disputation property of software source code, we have to prove the fact, there is a problem to discriminate the original software source code. In this paper, we make a study of the digital licence prototype for discriminate the original source code. Reserved words of software source code by parsing express to XML file that have hierarchical structure. Then, we can express node pattern and architecture pattern of software source code by tree structure form instead of complex software source code. And we make a simulation of discrimination possibility of digital license and propose CRYPTEX model.

Web services are being embraced by IT industry in the recent past to enable rapid development of distributed systems with optimal cost. Web services in SOA are self-adaptable to context, which makes SOA widely recognized in IT system as the technology, which has the potential of improving the receptiveness of both business and IT organizations. Web services help in building Service Based Systems (SBS) like Paytm, Amazon, Paypal, e-bay etc. which evolves frequently to fit the new user requirements which impacts the evolvability and quality of software design. Similar to software systems built using other paradigms, Service based systems also suffer from bad or poor design choices as in anti-pattern, code smells etc. Anti-patterns are explicit structures in the design that indicates violation of fundamental design principles and negatively impact the design quality. Anti-patterns have obstructive influence on the maintainability and perception of software systems. Thus there is a rising need for the early prediction of anti-patterns and refactoring them to improve the software quality in terms of execution cost, maintenance cost and memory consumption. In this work, a frame work is proposed for significant feature selection from source code metrics which includes Wilcoxon signed rank test, Univariate logistic regression analysis and Cross-correlation analysis. Then the different sets of features from various steps along with the original source code metrics are considered and are used for anti-pattern detection using 13 machine learning algorithms. Experimental results show the approximation capability of different classifiers and data balancing techniques with the features selected from the various steps of feature validation framework in addition to the original features for developing anti-pattern prediction model. The results also shows that the prediction model built with by the ensemble techniques using the features obtained from proposed feature selection framework outperforms other techniques.KeywordsSoftware engineeringAnti-patternWeb serviceImbalanced dataService oriented architectureMachine learningPredictionSource code metric

Federated Learning (FL) is a learning paradigm where multiple nodes collaboratively train a model by only exchanging updates or parameters. This enables to keep data locally, therefore enhancing privacy - statement requiring nuance, e.g. memorization of training data in language models. Depending on the application, the number of samples that each node contains can be very different, which can impact the training and the final performance. This work studies the impact of the per-node sample size distribution on the mean squared error (MSE) of the one-shot federated estimator. We focus on one-shot aggregation of statistical estimations made across disjoint, independent and identically distributed (i.i.d.) data sources, in the context of empirical risk minimization. In distributed learning, it is well-known that for a total number of m nodes, each node should contain at least m samples to equal the performance of centralized training. In a federated scenario, this result remains true, but now applies to the mean of the per-node sample size distribution. The demo enables to visualize this effect as well as to compare the behavior of the FESC (Federated Estimation with Statistical Correction) algorithm - a weighting scheme which depends on the local sample size - with respect to the classical federated estimator and the centralized one, for a large collection of distributions, number of nodes, and features space dimension. **This is an MLBriefs article, the source code has not been reviewed!**<br> **The original source code is [[available here|https://github.com/gonzaq94/one-shot-fed-learning]] (last checked 2023/02/12).**

Program transformations have been advocated as a method for accomplishing reverse engineering. The hypothesis is that the original source code can be progressively transformed into alternative forms, but with the same semantics. At the end of the process, an equivalent program is acquired, but one which is much easier to understand and more maintainable. We have been undertaking an extensive programme of research over twelve years into the design and development of transformations for the support of software maintenance. The paper very briefly explains the theory, practice and tool support for transformational systems, but does not present new theoretical results. The main results are on an analysis of the strengths and weaknesses of the approach, based on experience with case studies and industrial applications. The evaluation framework used (called DERE) is that presented in Bennett and Munro (1998). It is hoped that the results will be of benefit to industry, who might be considering using the technology; and to other researchers, interested in addressing the open problems. The overall conclusion is that transformations can help in the bottom-up analysis and manipulation of source code at approximately the 3GL level, and have proved successful in code migration, but need to be complemented by other top-down techniques to be useful at higher levels of abstraction or in more ambitious re-engineering projects.

The widespread availability of Large Language Models (LLMs) has significantly lowered the barrier to committing code plagiarism. However, most existing anti-plagiarism tools remain vulnerable to modern evasion strategies, including syntactic transformations and generative code rewriting. Prior work shows that such transformations can effectively bypass clone detectors that rely on syntactic or semantic representations. While binary optimization is a known technique in malware obfuscation, its potential for plagiarism detection has been largely overlooked. We introduce a hybrid detection method that combines source-level syntactic analysis with binary-level comparison, leveraging both standard compilation outputs and binaries generated with optimization flags. These optimizations act as a reverse filter, eliminating syntactic manipulations added to code artifacts and revealing structural similarities with the original binary. Our empirical evaluation confirms that optimized binaries exhibit patterns that correlate strongly with their original source code. The proposed method demonstrates high effectiveness in detecting plagiarism, even when the source code has undergone aggressive syntactic transformations. This technique serves as a robust and complementary extension to existing syntactic anti-plagiarism systems, offering deeper insight into semantic and structural code similarity.

Chapter 1 - Introduction

The authors present co-transformation, a novel approach to the mapping of execution information from the source code of a program to the object code for the purpose of worst-case execution time (WCET) analysis. Their approach is designed to handle the problems introduced by optimizing compilers, i.e. that the structure of the object code is very different from the structure of the source code. The co-transformer allows one to keep track of how different compiler transformations, including optimizations, influence the execution time of a program. This allows one to statically calculate the execution time of a program at the object code level, using information about the program execution obtained at the source code level.

The energy consumption optimization of embedded systems can be undertaken in multiple levels of hardware and software. In this paper, based on the energy consumption measurement of embedded software, the generating reasons and influencing factors of embedded software energy consumption on the micro-structure and circuit level of hardware were analyzed firstly. Then, to reduce the energy consumption of embedded software, some measures were adopted to improve the software-related characteristics on the source code and algorithm level. Finally, a C program of typical "Eight Queens" puzzle was optimized with three methods of source code level, algorithm level and a mix of source code and algorithm level, the highest energy savings of embedded systems could achieve up to 93.1%, and experimental results demonstrated that the energy consumption optimization methods of embedded software were feasible and effective to minimize the energy consumption of embedded systems.

Against the “Networked Information Economy”: Rethinking Decentralization, Community, and Free Software Development Ben Roberts (bio) The free, libre, and open source software (FLOSS) movement is often cited as an example of fundamental changes in production associated with the rise of information networks. Don Tapscott and Anthony D. Williams see it as an example of wikinomics, a powerful new form of economic production based on sharing and self-organization.1 Yochai Benkler argues that the form of social or peer production evident in FLOSS can compete with or even displace traditional forms of capitalist organization and sees it as a symptom of the “networked information economy,” replacing the “industrial information economy,” which has been in force since the late-nineteenth century.2 The main feature of this networked information economy is the much greater role within it for decentralized individual action.3 This essay contests this broadly liberal take on the significance of the free software movement. It argues that Benkler is typical of an approach that tends to view the Internet as the primary enabler of decentralization (for example, in the form of decentralized software development). Of course, it would be foolish to discount the role that networks have played in the success of FLOSS. But, as I will argue, an examination of its history suggests that its origins can’t be entirely accounted for in purely technological and economic grounds. The proponents of such an approach often resist the claim that their focus on networks is technologically determinist,4 arguing that the network itself is shaped by social and cultural factors. However, this makes the explanatory power of networks rather circular: the existence of networks explains social and cultural behavior at the same time as being explained by it. The explanation of free software in terms of the economic properties of networks is simply too static and asocial; it serves to explain how a particular mode of production can functionally compete with the market without really being able to account for how this change has come about. In particular, as I will show, the marginalization [End Page 385] of the question of labor in theories of peer production disconnects the analysis from wider changes in the nature of economic production. Moreover, the emphasis on the empowerment of individuals ignores the possibility that decentralization consists in radical new forms of sociality and collectivity, something that can perhaps be seen in the communities built around particular free software projects. As I will argue, Gilbert Simondon’s concept of individuation may help inform a better understanding of the emergence of such free software communities. From the perspective of a nonprogrammer, it is easiest to understand the concept of FLOSS by explaining how proprietary software such as Microsoft Windows is distributed. The operating system and applications that users run on their personal computers (PCs) are most often compiled software. The creators of the application have written the code in any one of a number of different human-readable programming languages; this program is known as the source code. The source code is then converted by another program known as a compiler into object or binary code, which is a machine-readable version of the program executed when the application is run on a PC. Binary, or object, code is the form in which software is most often distributed to users, either on installation media such as compact discs (CDs), installed on a computing device before sale or, increasingly, downloaded over the Net. The end user of proprietary software created and distributed in this fashion has no access to the original source code and is therefore unable to alter, change, or fix the software running on their machine: in the words of Bob Young, the former chief executive officer (CEO) of open source software company Red Hat, purchasing proprietary software is like buying a “car with the hood welded shut.”5 In addition to the absence of source code, proprietary software is usually distributed under the terms of a highly restrictive software license. In effect, the applications run by a user remain the property of the software maker and may be used only under the terms of this contract. Typically, the license prevents sharing...

The TPS test design process results in UUT detailed test strategy that is independent of its eventual implementation in source code or on a specific ATS. It is test strategy, not source code, that embodies the critical metrics of UUT fault detection and isolation. Source code implementation is the first step in a design chain that finally results in signal-information flow across the test interface. This SI flow is the physical realization of test design. The objective of TPS rehosting is usually preservation of proven legacy test design, but it should also seek to preserve legacy SI flow to avoid the subtle, and often difficult, problems caused by rehosting to the new ATS. These problems can be exacerbated by inability of the original source code to describe what is happening at the UUT test interface, and by the repeated and characteristic need to choose between equivalent performance of, and incidental or substantive enhancements to, the rehosted TPS.

SUMMARYAs a key part of reverse engineering, decompilation plays a very important role in software security and maintenance. A number of tools, such as Boomerang and IDA Hex_rays, have been developed to translate executable programs into source code in a relatively high‐level language. Unfortunately, most existing decompilation tools suffer from low accuracy in identifying variables, functions, and composite structures, resulting in poor readability. To address these limitations, we present a practical decompiler called C‐Decompiler for Windows C programs that (i) uses a shadow stack to perform refined data flow analysis, (ii) adopts inter‐basic‐block register propagation to reduce redundant variables, and (iii) recognizes library (i.e., Standard Template Library) functions by signatures. We evaluate and compare the decompilation quality of C‐Decompiler with two existing tools, Boomerang and IDA Hex_rays, considering four aspects: function analysis, variable expansion rate, total percentage reduction, and cyclomatic complexity. Our experimental results show that on average, C‐Decompiler has the highest total percentage reduction of 55.91%, lowest variable expansion rate of 55.79%, and the same cyclomatic complexity as the original source code for each considered application. Furthermore, in our experiments, C‐Decompiler is able to recognize functions with a lower false positive and false negative rate than the other decompilers. A case study and our evaluation results confirm that C‐Decompiler is a practical tool to produce highly readable C‐style code. Copyright © 2012 John Wiley &amp; Sons, Ltd.

Applications executing on multicore processors can now easily offload computations to many core processors, such as Intel Xeon Phi coprocessors. However, it requires high levels of expertise and effort to tune such offloaded applications to realize high-performance execution. Previous efforts have focused on optimizing the execution of offloaded computations on many core processors. However, we observe that the data transfer overhead between multicore and many core processors, and the limited device memories of many core processors often constrain the performance gains that are possible by offloading computations. In this paper, we present three source-to-source compiler optimizations that can significantly improve the performance of applications that offload computations to many core processors. The first optimization automatically transforms offloaded codes to enable data streaming, which overlaps data transfer between multicore and many core processors with computations on these processors to hide data transfer overhead. This optimization is also designed to minimize the memory usage on many core processors, while achieving the optimal performance. The second compiler optimization re-orders computations to regularize irregular memory accesses. It enables data streaming and factorization on many core processors, even when the memory access patterns in the original source codes are irregular. Finally, our new shared memory mechanism provides efficient support for transferring large pointer-based data structures between hosts and many core processors. Our evaluation shows that the proposed compiler optimizations benefit 9 out of 12 benchmarks. Compared with simply offloading the original parallel implementations of these benchmarks, we can achieve 1.16x-52.21x speedups.