NOVIA: A Framework for Discovering Non-Conventional Inline Accelerators

Accelerators provide an increasingly valuable source of performance in modern computing systems. In most cases, accelerators are implemented as stand-alone, offload engines to which the processor can send large computation tasks. For many edge devices, as performance needs increase accelerators become essential, but the tight constraints on these devices limit the extent to which offload engines can be incorporated. An alternative is inline accelerators, which can be integrated as part of the core and provide performance with much smaller start-up times and area overheads. While inline accelerators allow greater flexibility in the interface and acceleration of finer grain code, determining good inline candidate accelerators is non-trivial. In this paper, we present NOVIA, a framework to derive inline accelerators by examining the workload source code and identifying inline accelerator candidates that provide benefits across many different regions of the workload. These NOVIA-derived accelerators are then integrated into an embedded core. For this core, NOVIA produces inline accelerators that improve the performance of various benchmark suites like EEMBC Autobench 2.0 and Mediabench by 1.37x with only a 3% core area increase.