Towards a Reference Place and Route Flow for Academic Research

Abstract

Due to the complexity of contemporary circuits, physical synthesis has become a crucial step for achieving design closure. The placement of cells direct impacts the routing solution. For example, a region with a high cell density can lead to pin access issues in detailed routing. Therefore, small inefficiencies in the placement solution can be boosted during routing, which has a negative impact on design quality and convergence. Unfortunately, most academic research works evaluate the results only in the target step without considering the complete place and route flows. In this work, we experimentally explored different flows built up from academic placers and routers to find which one leads to the best overall results so that researchers can use them as a reference. In order to evaluate those flows, we used the ISPD 2018 and ISPD 2019 CAD Contest benchmarks, which are the most realistic academic benchmarks available with placement and routing information. Considering the evaluator reports, no combination of tools achieved the best result for all circuits. Nevertheless, the flow Contest placement + CUGR + TritonRoute achieved the best results in fifteen out of twenty benchmarks.

ILPGRC: ILP-Based Global Routing Optimization With Cell Movements

“…This experiment relied on the evaluation flow in Figure 8, except that we used DreamPlace [31] to generate new placement solutions for the ISPD Contests 2018 and 2019 circuits. The flow DreamPlace + CUGR + TritonRoute resulted in the second best placement to detailed routing flow reported in [30]. ILPGRC improves the wirelength in two circuits (19 t7 and 19 t5) while not increasing it by a maximum of 1.62%.…”

“…Although some academic tools are well-known for being state-of-the-art, we can not guess how those tools will interact with each other. To investigate such interaction, in our recent work [30] we evaluated twelve different flows built by combining three placements (original placement by contest, DreamPlace [31] and EhPlacer [32]), two Global Routing engines (CUGR [4] and FastRoute [33]), and two Detailed Routing tools (DRCU [5] and TritonRoute [7]). These flows were evaluated by using the ISPD Contest 2018 [13] and ISPD Contest 2019 [14] benchmarks.…”