Static Analysis to Support Change Management in Variant-rich Legacy Control Software for Machine and Plant Engineering companies (CHANGE aPS)

自动化生产系统（aPS），即机器和工厂是长寿命系统，通常由根据IEC 61131-3标准编程的实时可编程逻辑控制器（PLC）控制。由于控制软件的功能和复杂性不断增加，其计划重用变得越来越重要。与此同时，客户和不同的相关学科（例如，机械或电气/电子）通常通过改变控制软件来解决。然而，目前，在aPS域中的软件改变通常使用复制-粘贴-修改来实现，这产生大量的控制软件的未记录的变体和版本，并导致较低的软件质量和较高的维护成本。在这个转移项目中，我们的目标是开发更好的变更流程，并提高最终控制软件的质量。我们联合收割机将之前DFG资助的项目RED SPLAT（由TUM执行的aPS控制软件重构和相似性分析）和IMPROVE APS（由TUM和KIT联合执行的aPS控制软件的回归验证）的结果结合、应用和扩展到teamtechnik公司的两个应用领域，teamtechnik是一家世界领先的机械和设备工程公司（即GAMP认证的汽车和医疗软件）。因此，teamtechnik的目标是保持其作为机器和设备制造商的世界领先市场地位。将RED SPLAT和IMPROVE APS分别开发的结果结合成一种协同方法，可以进行包括语法和语义克隆识别的控制软件分析。首先，进行语法（结构）分析，以确定更改的软件部分，从而缩小代码，其次，使用回归验证进行软件更改的语义（行为）分析。在引导式访谈中收集真实的控制软件变更，包括变更原因和元数据（如注释和命名约定）。考虑了有关行业中执行的更改的信息，以增强对语义代码克隆的识别。开发的方法是嵌入到teamtechnik的控制软件工程过程。此外，变更分析和管理方法以原型方式实现，包括对不同涉众的可视化支持，例如，应用程序开发人员，专员或经理，以评估teamtechnik开发工作流程中的方法在实践中的适用性和有效性。在这个项目中获得的见解将提供进一步的研究，以确定控制软件中的语法，特别是语义代码克隆的提示。

Automated Production Systems (aPS), i.e., machines and plants, are long-living systems, usually controlled by real-time capable Programmable Logic Controllers (PLCs) programmed in accordance with the IEC 61131-3 standard. Due to the growing functionality and complexity of control software, its planned reuse is increasingly important. At the same time, evolving requirements and requests for additional functionalities from customers and the different involved disciplines (e.g., mechanics or electrics/electronics) are typically addressed by changing the control software. Currently, however, software changes in the aPS domain are typically implemented using Copy-Paste-Modify, which generates a high number of undocumented variants and versions of the control software and results in lower software quality and higher maintenance costs. In this transfer project, we aim to develop better change processes and improve the quality of the resulting control software. We combine, apply, and extend results from our previous DFG-funded projects RED SPLAT (aPS control software restructuring and similarity analysis, executed by TUM) and IMPROVE APS (regression verification of aPS control software, jointly executed by TUM and KIT) to two application sectors of the company teamtechnik, a world leading company in machine and plant engineering (namely automotive and medical-certified software according to GAMP). Thereby, teamtechnik aims to maintain its world-leading market position as a machine and plant manufacturer. Combining the separately developed results of RED SPLAT and IMPROVE APS into a synergetic approach enables a control software analysis that includes both syntactic and semantic clone identification. First, a syntactic (structural) analysis is performed to identify changed software parts and, thus, narrow down the code on which, second, a semantic (behavioral) analysis of software changes is performed using regression verification. Real control software changes are gathered in guided interviews, including the change reason and metadata like comments and naming conventions. This information on changes performed in the industry is taken into account to enhance the identification of semantic code clones. The developed approach is to be embedded in the control software engineering process of teamtechnik. Further, the change analysis and management methods are implemented prototypically, including visual support for different stakeholders, e.g., application developer, commissioner, or manager, to evaluate the approach in teamtechnik’s development workflow concerning its applicability and effectiveness in practice. The insights gained in this project will provide hints for further research on identifying syntactic and especially semantic code clones within control software.