Abstract-A traditional extensible processor with customized circuits achieves high performance at the cost of flexibility, while a dynamically extensible processor with reconfigurable fabric offers flexibility for instruction-set extensions (ISEs) but suffers from computational inefficiency. We introduce a novel architecture called Just-in-Time Customizable (JiTC) processor that reconciles the conflicting demands of performance and flexibility in extensible processors. Our key innovation is a multi-stage accelerator, called Specialized Functional Unit (SFU), that is tightly integrated in the processor pipeline. The SFU design is derived through a systematic study of a large range of representative embedded applications. The SFU can be reconfigured on per-cycle basis to support different application-specific instructions at near-ideal performance of an extensible processor. We also provide an automated compilation tool chain for JiTC processor. The experimental results confirm the efficiency and applicability of our approach.
The JIT Customizable (JiTC) processor REF includes a multistage Specialized Functional Unit (SFU), with logic and arithmetic operations, tightly coupled to the processor pipeline.
A just-in-time customizable processor
ICCAD '13
Computer Science