Microarchitecture Configurations and Floorplanning Co-Optimization

Microarchitecture configurations and floorplanning are keys to boost throughput, and they are strongly related. In this paper, we propose a new method to optimize them simultaneously. We first concentrate on floorplanning under given microarchitecture configurations. In addition to the objectives of conventional floorplanning methods, we minimize the throughput degradation caused by pipelined global interconnects based on efficient yet accurate models for microarchitecture throughput over pipeline stages of global interconnects. Our results show that an accurate trajectory piecewise-linear (TPWL) model incurs more offline setup time to obtain 13% better throughput than a rough access ratio-based model, and both models lead to much better throughput (up to 64% higher) compared with conventional floorplanning methods. We then build a unified throughput model parameterized for pipelined global interconnects and microarchitecture configurations based on the TPWL method and apply this model to efficiently explore over one million microarchitecture configurations and corresponding floorplan variations. We obtain microarchitecture configurations and floorplans with throughput 26.9% better than manually chosen microarchitecture followed by automatic floorplanning in a very recent paper.