Linux kernel compaction through cold code swapping

There is a growing trend to use general-purpose operating systems like Linux in embedded systems. Previous research focused on using compaction and specialization techniques to adapt a general-purpose OS to the memory-constrained environment, presented by most, embedded systems. However, there is still room for improvement: it has been shown that even after application of the aforementioned techniques more than 50% of the kernel code remains unexecuted under normal system operation. We introduce a new technique that reduces the Linux kernel code memory footprint, through on-demand code loading of infrequently executed code, for systems that support virtual memory. In this paper, we describe our general approach, and we study code placement algorithms to minimize the performance impact of the code loading. A code, size reduction of 68% is achieved, with a 2.2% execution speedup of the system-mode execution time, for a case study based on the MediaBench II benchmark suite

Program transformations using temporal logic side conditions

This paper describes an approach to program optimisation based on transformations, where temporal logic is used to specify side conditions, and strategies are created which expand the repertoire of transformations and provide a suitable level of abstraction. We demonstrate the power of this approach by developing a set of optimisations using our transformation language and showing how the transformations can be converted into a form which makes it easier to apply them, while maintaining trust in the resulting optimising steps. The approach is illustrated through a transformational case study where we apply several optimisations to a small program

Formal Compiler Implementation in a Logical Framework

The task of designing and implementing a compiler can be a difficult and error-prone process. In this paper, we present a new approach based on the use of higher-order abstract syntax and term rewriting in a logical framework. All program transformations, from parsing to code generation, are cleanly isolated and specified as term rewrites. This has several advantages. The correctness of the compiler depends solely on a small set of rewrite rules that are written in the language of formal mathematics. In addition, the logical framework guarantees the preservation of scoping, and it automates many frequently-occurring tasks including substitution and rewriting strategies. As we show, compiler development in a logical framework can be easier than in a general-purpose language like ML, in part because of automation, and also because the framework provides extensive support for examination, validation, and debugging of the compiler transformations. The paper is organized around a case study, using the MetaPRL logical framework to compile an ML-like language to Intel x86 assembly. We also present a scoped formalization of x86 assembly in which all registers are immutable

12th International Workshop on Termination (WST 2012) : WST 2012, February 19–23, 2012, Obergurgl, Austria / ed. by Georg Moser

This volume contains the proceedings of the 12th International Workshop on Termination (WST 2012), to be held February 19–23, 2012 in Obergurgl, Austria. The goal of the Workshop on Termination is to be a venue for presentation and discussion of all topics in and around termination. In this way, the workshop tries to bridge the gaps between different communities interested and active in research in and around termination. The 12th International Workshop on Termination in Obergurgl continues the successful workshops held in St. Andrews (1993), La Bresse (1995), Ede (1997), Dagstuhl (1999), Utrecht (2001), Valencia (2003), Aachen (2004), Seattle (2006), Paris (2007), Leipzig (2009), and Edinburgh (2010). The 12th International Workshop on Termination did welcome contributions on all aspects of termination and complexity analysis. Contributions from the imperative, constraint, functional, and logic programming communities, and papers investigating applications of complexity or termination (for example in program transformation or theorem proving) were particularly welcome. We did receive 18 submissions which all were accepted. Each paper was assigned two reviewers. In addition to these 18 contributed talks, WST 2012, hosts three invited talks by Alexander Krauss, Martin Hofmann, and Fausto Spoto

"Who Gets Translated and Why? Anthologies of Twentieth-Century Greek Poetry in Poland"

The translation of Modern Greek poetry in Poland began on a regular basis at the end of the 1960s and falls into two broad categories: anthologies and the poetry of Cavafy. Cavafy’s work in Polish rendition must be seen as a separate domain: as in other countries, he has overshadowed the achievements of other Modern Greek poets. There is, however, a significant body of work by other poets available to the reader of Polish in anthologies compiled by prolific and influential translators, whose different backgrounds and motivations generate the question of who has been translated and why. This article demonstrates that the selection of poems and modes of translation are largely driven by extraliterary factors such as sociopolitical conditions, the readership, the publishing market, etc. The resultant Polish texts therefore provide a characteristic example of “rewriting” as defined by André Lefevere

Pedagogies of Design and Multiliterate Learner Identities

In an era of multiliteracies, teaching and learning have become knowledge performances at multiple levels. Instead of a singular, linear focus upon print technologies, the techno-oriented philosophy of teaching aims at providing a rhizomatic network of texts where there is a close link between, and often an overlap of, different designs—linguistic, visual, spatial, and gestural—to construct the multiliterate learner. In this paper, I discuss the role of multimodal literacies in a primary classroom, affirming the role of multiliteracies and decentring the pre-dominance of linguistic at the cost of other designs. While the print media are acknowledged as significant to literacy, the multimodality of print is enhanced through visual and spatial design (Kenner, 2004). Through graphic examples of ICT applications of designs in a primary classroom, I demonstrate that students are operating through multitextual and digitextual (Everett, 2003) practices. What follows is the complex positioning and re-situating of teacher and learner identities engaged in learning through the knowledge processes of experiencing, identifying, applying and critiquing concepts (Kalantzis & Cope, 2004). In particular, I argue that within the diversity of present day classrooms, the digital oriented, multiliterate learner is implicated in constant identity construction by drawing upon macro and micro social practices. I conclude by reiterating the significance of new technologies and new literacy practices as essential to the construction of new learner identities

Towards an aspect weaving BPEL engine

This position paper proposes the use of dynamic aspects and the visitor design pattern to obtain a highly configurable and extensible BPEL engine. Using these two techniques, the core of this infrastructural software can be customised to meet new requirements and add features such as debugging, execution monitoring, or changing to another Web Service selection policy. Additionally, it can easily be extended to cope with customer-specific BPEL extensions. We propose the use of dynamic aspects not only on the engine itself but also on the workflow in order to tackle the problems of Web Service hot deployment and hot fixes to long running processes. In this way, composing aWeb Service "on-the-fly" means weaving its choreography interface into the workflow