Transparent Replication Using Metaprogramming in Cyan

Replication can be used to increase the availability of a service by creating many operational copies of its data called replicas. Active replication is a form of replication that has strong consistency semantics, easier to reason about and program. However, creating replicated services using active replication still demands from the programmer the knowledge of subtleties of the replication mechanism. In this paper we show how to use the metaprogramming infrastructure of the Cyan language to shield the application programmer from these details, allowing easier creation of fault-tolerant replicated applications through simple annotations.Comment: 8 page

PyCUDA and PyOpenCL: A Scripting-Based Approach to GPU Run-Time Code Generation

High-performance computing has recently seen a surge of interest in heterogeneous systems, with an emphasis on modern Graphics Processing Units (GPUs). These devices offer tremendous potential for performance and efficiency in important large-scale applications of computational science. However, exploiting this potential can be challenging, as one must adapt to the specialized and rapidly evolving computing environment currently exhibited by GPUs. One way of addressing this challenge is to embrace better techniques and develop tools tailored to their needs. This article presents one simple technique, GPU run-time code generation (RTCG), along with PyCUDA and PyOpenCL, two open-source toolkits that support this technique. In introducing PyCUDA and PyOpenCL, this article proposes the combination of a dynamic, high-level scripting language with the massive performance of a GPU as a compelling two-tiered computing platform, potentially offering significant performance and productivity advantages over conventional single-tier, static systems. The concept of RTCG is simple and easily implemented using existing, robust infrastructure. Nonetheless it is powerful enough to support (and encourage) the creation of custom application-specific tools by its users. The premise of the paper is illustrated by a wide range of examples where the technique has been applied with considerable success.Comment: Submitted to Parallel Computing, Elsevie

A Case for Custom, Composable Composition Operators

Programming languages typically support a fixed set of com- position operators, with fixed semantics. This may impose limits on software designers, in case a desired operator or semantics are not supported by a language, resulting in suboptimal quality characteristics of the designed software system. We demonstrate this using the well-known State design pattern, and propose the use of a composition infrastructure that allows the designer to define custom, composable composition operators. We demonstrate how this approach improves several quality factors of the State design pattern, such as reusability and modularity, while taking a reason- able amount of effort to define the necessary pattern-related code

Static Computation and Reflection

Thesis (PhD) - Indiana University, Computer Sciences, 2008Most programming languages do not allow programs to inspect their static type information or perform computations on it. C++, however, lets programmers write template metaprograms, which enable programs to encode static information, perform compile-time computations, and make static decisions about run-time behavior. Many C++ libraries and applications use template metaprogramming to build specialized abstraction mechanisms, implement domain-specific safety checks, and improve run-time performance. Template metaprogramming is an emergent capability of the C++ type system, and the C++ language specification is informal and imprecise. As a result, template metaprogramming often involves heroic programming feats and often leads to code that is difficult to read and maintain. Furthermore, many template-based code generation and optimization techniques rely on particular compiler implementations, rather than language semantics, for performance gains. Motivated by the capabilities and techniques of C++ template metaprogramming, this thesis documents some common programming patterns, including static computation, type analysis, generative programming, and the encoding of domain-specific static checks. It also documents notable shortcomings to current practice, including limited support for reflection, semantic ambiguity, and other issues that arise from the pioneering nature of template metaprogramming. Finally, this thesis presents the design of a foundational programming language, motivated by the analysis of template metaprogramming, that allows programs to statically inspect type information, perform computations, and generate code. The language is specified as a core calculus and its capabilities are presented in an idealized setting

An Overview of the Mjølner BETA System

The Mjølner BETA System is an integrated and interactive programming environment with support for industrial object oriented programming. The Mjølner BETA System is a result of the Scandinavian research project Mjølner. The integration of the various tools in the Mjølner BETA System is established by insisting that all tools in the system utilizes on single representation of the program. This representation is abstract syntax trees (ASTs). All manipulations of the ASTs by the various tools are done utilizing the metaprogramming system which defines an interface to the AST and ways to manipulate the AST