Solving the TTC 2011 Reengineering Case with GrGen.NET

The challenge of the Reengineering Case is to extract a state machine model out of the abstract syntax graph of a Java program. The extracted state machine offers a reduced view on the full program graph and thus helps to understand the program regarding the question of interest. We tackle this task employing the general purpose graph rewrite system GrGen.NET (www.grgen.net).Comment: In Proceedings TTC 2011, arXiv:1111.440

Solving the TTC 2011 Compiler Optimization Task with metatools

The authors' "metatools" are a collection of tools for generic programming. This includes generating Java sources from mathematically well-founded specifications, as well as the creation of strictly typed document object models for XML encoded texts. In this context, almost every computer-internal structure is treated as a "model", and every computation is a kind of model transformation. This concept differs significantly from "classical model transformation" executed by specialized tools and languages. Therefore it seemed promising to the organizers of the TTC 2011, as well as to the authors, to apply metatools to one of the challenges, namely to the "compiler optimization task". This is a report on the resulting experiences.Comment: In Proceedings TTC 2011, arXiv:1111.440

FIRM - A Graph-Based Intermediate Representation

We present our compiler intermediate representation Firm. Programs are always in SSA-form enabling a representation as graphs. We argue that this naturally encodes context information simplifying many analyses and optimizations. Instructions are connected by dependency edges relaxing the total to a partial order inside a basic block. For example alias analysis results can be directly encoded in the graph structure. The paper gives an overview of the representation and focuses on its construction. We present a simple construction algorithm which does not depend on dominance frontiers or a dominance tree. We prove that for reducible programs it produces a program in pruned and minimal SSA-form. The algorithm works incrementally so optimizations like copy propagation and constant folding can be performed on-the-fly during the construction

Solving the TTC 2011 Compiler Optimization Case with QVTR-XSLT

In this short paper we present our solution for the Compiler Optimization case study of the Transformation Tool Contest (TTC) 2011 using the QVTR-XSLT tool. The tool supports editing and execution of the graphical notation of QVT Relations languageComment: In Proceedings TTC 2011, arXiv:1111.440

Synthesizing Instruction Selection

Instruction selection is the part in a compiler that transforms IR code into machine code. Instruction selectors build on a library of hundreds if not thousands of rules. Creating and maintaining these rules is a tedious and error-prone manual process. In this paper, we present a fully automatic approach to create provably correct rule libraries from formal specifications of the instruction set architecture and the compiler IR using template-based counter-example guided synthesis (CEGIS). Thereby, we overcome several shortcomings of an existing SMT-based CEGIS approach, which was not applicable to our setting in the first place.We propose a novel way of handling memory operations and show how the search space can be iteratively explored to synthesize rules that are relevant for instruction selection. Our approach synthesized a large part of the integer arithmetic rules for the x86 architecture within a few days where existing techniques could not deliver a substantial rule library within weeks. With respect to the runtime of the compiled programs, we show that the synthesized rules are close to a manually-tuned instruction selector

Saying Hello World with GReTL - A Solution to the TTC 2011 Instructive Case

This paper discusses the GReTL solution of the TTC 2011 Hello World case. The submitted solution covers all tasks including the optional ones.Comment: In Proceedings TTC 2011, arXiv:1111.440

Bewegung/en: Tagungsbericht zur Jahrestagung der Fachgesellschaft Geschlechterstudien vom 13. bis 14. Februar 2015 an der Universität Bielefeld

Vom 13. bis 14. Februar 2015 fand die fünfte Jahrestagung der Fachgesellschaft Geschlechterstudien/ Gender Studies Association unter dem Titel "Bewegung/en" statt. In anregenden Vorträgen und Diskussionen zeigten sich unterschiedlichste Herangehensweisen, die sich gut miteinander ergänzten und einen facettenreichen Blick auf das Thema "Bewegung/en" ermöglichten. Deutlich wurde, dass der Begriff "Bewegung/en" das Potenzial hat, sowohl den Gegenstand - die Bewegung/en - als auch das (forschende) Bewegen an sich in den wissenschaftlichen Fokus zu rücken.“Movement/s”. Annual Conference of the Gender Studies Association, University of Bielefeld, 13/14 February 2015 The 5th Annual Conference of the Gender Studies Association entitled “Movement/s”, which was held in Bielefeld in February 2015, provided plenty of opportunity for thoughtprovoking lectures and interesting discussions. Diverse perspectives and methodological approaches came to the fore and complemented each other, thereby revealing the many facets of the theme of “movement/s”. It became clear that the term “movement/s” has the potential to both put the focus on the object of research – (social) movements – and on the moves we make when doing scientific research