Allowing Software Developers to Debug HLS Hardware

High-Level Synthesis (HLS) is emerging as a mainstream design methodology, allowing software designers to enjoy the benefits of a hardware implementation. Significant work has led to effective compilers that produce high-quality hardware designs from software specifications. However, in order to fully benefit from the promise of HLS, a complete ecosystem that provides the ability to analyze, debug, and optimize designs is essential. This ecosystem has to be accessible to software designers. This is challenging, since software developers view their designs very differently than how they are physically implemented on-chip. Rather than individual sequential lines of code, the implementation consists of gates operating in parallel across multiple clock cycles. In this paper, we report on our efforts to create an ecosystem that allows software designers to debug HLS-generated circuits in a familiar manner. We have implemented our ideas in a debug framework that will be included in the next release of the popular LegUp high-level synthesis tool.