Utilizing Control Independence and Multi-Threading to Exploit P

该项目的主要目标是研究利用控制独立性和编译器指导的多线程来利用普通程序的指令级和线程级并行性的技术。第一步是研究在利用控制独立性和多线程时存在的ILP的科学。解决的一些问题是：利用并行性需要什么；可以通过诸如判定执行或数据值预测之类的简单技术来利用多少并行性；指令应该(静态地或动态地)移动到多远以利用它；它是如何受到实际考虑的影响的；软件转换如何增强它；应该对代码的哪些部分执行软件转换；这些转换的性质应该是什么；以及利用可用并行性所需的存储的特征是什么？第二步涉及调查硬件和软件技术，以利用多线程环境中控制独立性和数据推测的好处。特别是，研究了使用新方法来表示/指定控制独立性(和数据独立性)。使用详细的仿真模型研究了与多线程相关的问题，如推测路径数量和性能之间的权衡。

The primary objective of the project is to investigate techniques to utilize control independence and compiler-directed multi-threading to exploit instruction-level and thread-level parallelism from ordinary programs. The first step involves investigating the science of ILP that is present when utilizing control independence and multi-threading. Some of the questions that are addressed are: what is required to exploit parallelism, how much of the parallelism can be exploited by simple techniques such as predicated execution or data value prediction, how far should instructions be moved (statically or dynamically) to exploit it how is it impacted by practical considerations, how can it be enhanced by software transformations, on which portions of the code should software transformations be carried out and what should the nature of these transformations be, and what are the characteristics of the storage needed to exploit the available parallelism?The second step involves investigating hardware and software techniques to exploit the benefits of control independence and data speculation in a multi-threading environment. In particular, the use of novel methods to represent/specify control independence (and data independence) is investigated. Issues relevant to multi-threading, such as tradeoffs between the number of speculative paths and performance are also studied using detailed simulation models.