CSR-EHS: Enhancing the Effectiveness of Utilizing an Instruction Register File

嵌入式应用程序必须满足不同的、经常是相互冲突的约束，包括能耗、空间和时间。虽然可以开发编译器优化和/或架构特性来改进嵌入式应用程序的一个方面，但它通常会损害另一个方面。指令寄存器文件（IRF）可以帮助实现这些目标。经常使用的指令被放在IRF中，多个IRF指令可以被ROM中的单个打包指令或一级（L1）指令缓存引用。这种方法允许在从内存系统获取的单个指令中引用多个指令，并导致可执行文件中同一指令的多个实例被较小的IRF索引替换。本研究探讨了各种技术，以提高利用IRF的有效性。通过增加从IRF引用的指令的数量，可以进一步降低能耗并减小代码大小。该项目正在实现许多编译和体系结构技术，以解决以前对应用程序中打包的指令数量的限制。该研究还探讨了IRF如何补充其他编译器优化和/或架构特性，从而节省能源和减少代码大小。最后，本研究对不同指令集进行了实验，并参考了来自存储系统和IRF的指令，以确定提供更大灵活性和整体效率的方法。

Embedded applications have to meet different and often conflicting constraints involving energy consumption, space, and time. While a compiler optimization and/or an architectural feature may be developed to improve one aspect of an embedded application, it often comes at the detriment of another. An instruction register file (IRF) can help to achieve these goals. Frequently used instructions are placed in the IRF, and multiple IRF instructions can be referenced by a single packed instruction in ROM or a level-one (L1) instruction cache. This approach enables multiple instructions to be referenced in a single instruction fetched from the memory system and resultsin multiple instances of the same instruction in the executable being replaced with a smaller IRF index. This research investigates a variety of techniques to enhance the effectiveness of utilizing an IRF. By increasing the number of instructions referenced from the IRF, it is possible to further reduce energy consumption and decrease code size. The project is implementing a number of compilation and architectural techniques to address previous limitations on the number of instructions being packed in an application. The research also explores how an IRF can complement other compiler optimizations and/or architectural features that save energy and reduce code size. Finally, the research pursues experimentation with different instruction sets, over instructions referenced from the memory system and the IRF, to identify approaches that provide greater flexibility and overall efficiency.