A Unifying Framework for Parallelizing Transformations

为了有效地利用并行系统的资源，编译器必须进行转换，以增加程序代码的并行度或提高开发并行性的效率。然而，转换之间的交互以及转换和调度之间的交互还没有被很好地理解。应用转换的指导方针、转换的成本和收益比率以及对转换后的代码进行操作的工具的设计尚未充分制定。本研究对这些问题进行了研究。用于并行化转换的统一框架和一组用于指定可以安全应用转换的条件的依赖项。该框架将从两个层面进行描述：定义性和可操作性。使用框架的定义级别，将研究启用和禁用转换之间以及转换和调度之间的交互。该框架的操作级别将用于生成和支持转换代码的工具的开发和原型制作，特别是转换工具生成器、生成器和结果转换器的接口工具以及符号错误生成器。将使用该框架调查转型的成本和收益。将制定一套基于相互作用、成本和收益的转型应用指南，并考虑到调度策略、方案结构、体系结构和可用资源。这些工具将被设计为对框架中可表达的任何一组转换进行操作。将研究该框架用于用户定义的变换的实用性。在整个工作中，将进行实验，将框架转换方法与传统的手工转换方法进行比较。

To effectively utilize the resources of parallel systems, transformations are necessarily applied by compilers to increase the degree of parallelism in program code or to improve the efficiency of exploiting parallelism. However, the interactions among the transformations as well as the interactions between transformations and scheduling are not well understood. Guidelines for applying transformations, ratios of the cost and benefit of the transformations and the design of tools that operate on the transformed code have yet to be adequately developed. This research investigates these issues. A unifying framework for parallelizing transformations and a set of dependencies that is used to specify the conditions under which a transformation may be safely applied. The framework will be described on two levels: definitional, and operational. Using the definitional level of the framework, enabling and disabling interactions among the transformations and between transformation and scheduling will be studied. The operational level of the framework will be employed in the development and prototyping of tools that generate and support transformed code, and in particular a transformation tool generator, interface tools for the generator and resulting transformer, and a symbolic bugger. Costs and benefits of transformations will be investigated using the framework. A set of guidelines will be developed for the application of transformations base on their interaction, costs, and benefits, taking into account scheduling strategies, program structure, architecture, and resources available. These tools will be designed to operate on any set of transformations expressible in the framework. The utility of the framework for user defined tranformations will be investigated. Throughout the work, experimentation will be performed comparing the framework approach to transformation with the traditional approach of hand-crafting transformations.