Design Space Exploration of Distributed Loop Buffer Architectures with Incompatible Loop-Nest Organisations in Embedded Systems

摘要

The use of distributed loop buffer architectures with incompatible loop-nest organisations allows the execution of incompatible loops in parallel with minimal hardware overhead. Due to this fact, the utilisation of these distributed and scalable architectures in embedded systems is a promising option to improve the energy efficiency of the instruction memory organisations that exist in these systems. This paper proposes and analyses non-overlapping and complementary implementation options for distinct partitions of the design space that is related to distributed loop buffer architectures. The high-level trade-off analysis of the proposed implementations is crucial to present the correct process design that an embedded systems designer has to follow in order to have an efficient distributed loop buffer architecture for a certain application. Results show that, with an increase of about 6.5 % in the energy consumption of the control logic that exists in the instruction memory organisation, the overall energy consumption of the instruction memory organisation can be reduced by 6 % to 22 %, when distributed loop buffer architectures with incompatible loop-nest organisations are used instead of clustered loop buffer architectures with shared loop-nest organisations architectures.