Evaluating Various Branch-Prediction Schemes for Biomedical-Implant Processors

This paper evaluates various branch-prediction schemes under different cache configurations in terms of performance, power, energy and area on suitably selected biomedical workloads. The benchmark suite used consists of compression, encryption and data-integrity algorithms as well as real implant applications, all executed on realistic biomedical input datasets. Results are used to drive the (micro)architectural design of a novel microprocessor targeting microelectronic implants. Our profiling study has revealed that, under strict or relaxed area constraints and regardless of cache size, the ALWAYS TAKEN and ALWAYS NOT-TAKEN static prediction schemes are, in almost all cases, the most suitable choices for the envisioned implant processor. It is further shown that bimodal predictors with small Branch-Target-Buffer (BTB) tables are suboptimal yet also attractive solutions when processor I/D-cache sizes are up to 1024KB/512KB, respectively.