Exploring processor parallelism: Estimation methods and optimization strategies

Former research on automatic exploration of ASIP architectures mostly focused on either the internal memory hierarchy, or the addition of complex custom operations to RISC based architectures. This paper focuses on VLIW architectures and, more specifically, on automating the selection of an application specific VLIW issue-width. An accurate and efficient issue-width estimation strongly influences all the important processor properties (e.g. processing speed, silicon area, and power consumption). We first compare different methods for estimating the required issue-width, and subsequently introduce a new force-based parallelism measure which is capable of estimating the required issue-width within 3% on average. Moreover, we show that we can quickly estimate the latency-parallelism Pareto-front of an example ECG application with less than 10% error using our issue-width estimations.