Automated Processor Configuration and Instruction Extension

Publisher Summary The application-specific instruction-set processor (ASIP) concept is reviewed in this chapter and discusses automated processor configuration. Tailoring a processor to an application has been more of an art than an exact science, and the process demands effort when done on a manual ad hoc basis. Many existing approaches to ASIP creation require the in-depth knowledge of a processor architect, the software knowledge of applications specialists, and the hardware-implementation skills of a team of experienced digital designers. Both structural, coarse-grained configuration parameters (for example, the inclusion or exclusion of functional units, the width of processor-to-memory or bus interfaces, the number and size of local and system memories), and fine-grained instruction extensions (the addition of application-specific tuned instructions that accelerate the processing of major functional application kernels by a factor of 2 ×, 10 ×, and more) are possible in ASIP configuration. Deciding the specific configuration parameters and extended instructions can be akin to finding the optimal needle in the proverbial haystack—and requires years of broad experience in a host of design disciplines. With this in mind, the design and use of ASIPs on a widespread basis across multiple application domains demand a more automated process for creating these processors from high-level configuration specifications.