Efficient Number of Functional Units and Loop Pipeline Design Space Exploration for High-Level Synthesis.

High-level synthesis compilers offer numerous directives for controlling hardware architecture implementations, leading to highly customized solutions, but also to large design spaces that are impractical to be fully explored due to the time-consuming stages of hardware compilation and synthesis. Traditional design space exploration approaches aim to identify architectures with the best hardware resources-performance balance. However, they usually consider the compilation process as a black box, failing to leverage relationships between directives and evaluation metrics to improve their efficiency. This paper analyses the relationship between the "number of functional units" and "loop pipeline" directives, which allow for balancing hardware area and computation time. For the former, we propose a novel path-based method to solve the shortcomings of traditional exploration approaches. For the latter, we propose a novel incremental exploration flow based on a Pareto-frontier evaluation. Results show improvements in exploration speed and quality of hardware designs when compared to established methods.