Mind the (synthesis) gap: Examining where academic FPGA tools lag behind industry

Firstly, we present VTR-to-Bitstream v2.0, the latest version of our open-source toolchain that takes Verilog input and produces a packed, placed - and now routed -solution that can be programmed onto the Xilinx commercial FPGA architecture. Secondly, we apply this updated tool to measure the gap between academic and industrial FPGA tools by examining the quality of results at each of the three main compilation stages: synthesis, packing & placement, routing. Our findings indicate that the delay gap (according to Xilinx static timing analysis) for academic tools breaks down into a 31% degradation with synthesis, 10% with packing & placement, and 15% with routing. This leads us to believe that opportunities for improvement exist not only within VPR, but also in the front-end tools that lie upstream.