One of the latest tools in the strive troughwards a fast and secure Web is called WebAssembly. It is a low-level, assembly-like language that can run in the browser alongside JavaScript. WebAssembly is designed to load fast and aims to execute at near-native speed. Being a compilation target for system languages like C, C++, and Rust, WebAssembly is not very accessible from a Web developer perspective. This project explores ways to generate WebAssembly directly from JavaScript code, in order to lower the learning curve, and allow for a more widespread adoption of WebAssembly. This has resulted in a utility tool called Esmbly, which can turn simple JavaScript programs into WebAssembly binaries by collecting and utilizing type information from various flavours of statically typed JavaScript.

The Swedish Armed Forces are currently considering extending the operational life of the Saab JAS 39 Gripen C/D multirole fighter aircraft by an additional 10 to 20 years. This has resulted in a need to upgrade many of the hardware components originally developed in the late 1980s and early 1990s. These upgrades include the Application Specific Integrated Circuits (ASICs) used to generate graphics in the aircraft’s Cockpit Display System (CDS), made programmable through the Symbol Programming Language (SPL). SPL is a proprietary Domain Specific Language (DSL) developed specifically to be used with the custom hardware in the Gripen’s CDS. An upgrade of the underlying hardware would necessitate migrating the old SPL software to some other format suitable for modern hardware. Large parts of this process could be automated with the help of a source-to-source compiler, i.e., a transpiler. In this thesis, we present a translation-verifying transpiler for a subset of SPL, dubbed μSPL, that outputs equivalent OpenGL/C++ programs. Verification is done at runtime against a reference program execution trace produced by the transpiler by means of symbolic execution in the operational semantics of μSPL. An observational study was made to evaluate the solution and the soundness of the μSPL semantics. From the results of the observational evaluation, we find that the chosen method for translation verification is contextually suitable, albeit with potential for improvement in the details of the implementation. / Försvarsmakten överväger i skrivande stund att förlänga tjänsteperioden för enhetflygplanet Saab JAS 39 Gripen C/D med ytterligare 10 till 20 år. Detta har resulterat i ett behov av att uppgradera många av de hårdvarukomponenter som ursprungligen togs fram för Gripenprojektet under sena 1980-talet och tidiga 1990-talet. Dessa uppgraderingar inkluderar applikationsspecifika integrerade kretsar (ASIC:ar) som används för att driva och generera symbolik för presentationssystemet Elektroniskt Presentationssystem 17 (EP-17) i cockpit på Gripen C/D. Dessa ASIC:ar är programmerbara med det egenutvecklade grafikprogramspråket SPL. En uppgradering av den underliggande hårdvaran skulle nödvändiggöra en migration av den SPL-mjukvara som redan är skriven till något format som är lämpligt för modern hårdvara. Stora delar av den här processen skulle kunna automatiseras med en automatisk översättare; en så kallad transpilator. I den här avhandlingen presenterar vi en översättningsverifierande transpilator för en delmängd av SPL, kallad μSPL, som översätter till ekvivalenta OpenGL/C++ program. Verifiering görs under körning mot ett exekveringsspår (execution trace) som producerats av transpilatorn parallellt med översättningen med hjälp av symbolisk exekvering i den operationella semantiken för μSPL. En observationell studie görs för att utvärdera lösningen och sundheten hos den använda μSPL-semantiken. Från den observationella studien framgår det att den föreslagna metoden för översättningsverifikation är lämplig i sammanhanget, med utrymme för förbättring i implementationsdetaljerna.

The concept of translating source code into other target programming languages is extensively used in a wide area of applications. Danfoss Power Solutions AB, a company located in Älmhult, strives to streamline their way of software development for microcontrollers by implementing this idea. Their proprietary software tool PLUS+1 GUIDE is based on the CAN bus communication network, which allows electronic control units to share data represented in the XML format. Due to compatibility problems, the application in the electronic control units requires this data to be translated into the source code in the low-level C programming language. This thesis project proposes an approach for facilitating this task by implementing a source-to-source compiler that performs the translation with a reduced level of manual user involvement. A literature review was conducted in order to find the existing solutions relevant to our project task. An analysis of the provided XML input files was thereafter performed to clarify a software design suitable for the problem. By using a general XML parser, a solution was then constructed. The implementation resulted in a fully functional source-to-source compiler, producing the generated C code within a time range of 73–85 milliseconds for the input test files of typical size. The feedback received from the domain experts at Danfoss confirms the usability of the proposed solution.