论文标题
PowerGear:FPGA HLS中的早期功率估算通过异质边缘GNNS
PowerGear: Early-Stage Power Estimation in FPGA HLS via Heterogeneous Edge-Centric GNNs
论文作者
论文摘要
功率估计是许多硬件优化策略的基础。但是,在早期阶段(例如高级合成(HLS))提供准确的功率估算仍然是具有挑战性的。在本文中,我们提出了PowerGear,这是FPGA HLS的图形学习辅助功率估计方法,该方法具有高精度,效率和可传递性。 PowerGear包括两个主要组成部分:图形构造流和定制的图形神经网络(GNN)模型。具体而言,在图形构造流中,我们介绍了缓冲区插入,数据合并合并,图形修剪和特征注释技术,以将HLS设计转换为图形结构化数据,该数据同时编码了与开关活动相结合的内部微体系结构和操作互连的互连。此外,我们提出了一种新型的功率感知异质边缘GNN模型,该模型有效地学习了通过中心的邻域聚集来学习构造图的异质边缘语义和结构特性,并符合动态功率的制定。与机上测量相比,PowerGear估计了新的HLS设计的总和和动态功率,错误分别为3.60%和8.81%,这表现优于研究和商业产品Vivado的先前艺术。此外,PowerGear在Vivado Power估算器上表现出4倍的加速。最后,我们提出了一项案例研究,其中利用PowerGear来促进FPGA HLS的设计空间探索,与使用最先进的预测模型的方法相比,高达11.2%的性能增长了11.2%。
Power estimation is the basis of many hardware optimization strategies. However, it is still challenging to offer accurate power estimation at an early stage such as high-level synthesis (HLS). In this paper, we propose PowerGear, a graph-learning-assisted power estimation approach for FPGA HLS, which features high accuracy, efficiency and transferability. PowerGear comprises two main components: a graph construction flow and a customized graph neural network (GNN) model. Specifically, in the graph construction flow, we introduce buffer insertion, datapath merging, graph trimming and feature annotation techniques to transform HLS designs into graph-structured data, which encode both intra-operation micro-architectures and inter-operation interconnects annotated with switching activities. Furthermore, we propose a novel power-aware heterogeneous edge-centric GNN model which effectively learns heterogeneous edge semantics and structural properties of the constructed graphs via edge-centric neighborhood aggregation, and fits the formulation of dynamic power. Compared with on-board measurement, PowerGear estimates total and dynamic power for new HLS designs with errors of 3.60% and 8.81%, respectively, which outperforms the prior arts in research and the commercial product Vivado. In addition, PowerGear demonstrates a speedup of 4x over Vivado power estimator. Finally, we present a case study in which PowerGear is exploited to facilitate design space exploration for FPGA HLS, leading to a performance gain of up to 11.2%, compared with methods using state-of-the-art predictive models.