This paper proposes ISDC, a novel feedback-guided iterative system of
difference constraints (SDC) scheduling algorithm for high-level synthesis
(HLS). ISDC leverages subgraph extraction-based low-level feedback from
downstream tools like logic synthesizers to iteratively refine HLS scheduling.
Technical innovations include: (1) An enhanced SDC formulation that effectively
integrates low-level feedback into the linear-programming (LP) problem; (2) A
fanout and window-based subgraph extraction mechanism driving the feedback
cycle; (3) A no-human-in-loop ISDC flow compatible with a wide range of
downstream tools and process design kits (PDKs). Evaluation shows that ISDC
reduces register usage by 28.5% against an industrial-strength open-source HLS
tool.

该论文提出了一种名为 ISDC 的新型反馈引导的迭代系统差别约束（SDC）调度算法，用于高层综合（HLS）。ISDC 利用下游工具如逻辑综合器提供的基于子图提取的低层反馈，迭代改进 HLS 调度。技术创新包括：（1）增强的 SDC 形式化，有效将低层反馈整合到线性规划（LP）问题中；（2）基于扇出和窗口的子图提取机制驱动反馈循环；（3）无需人为干预的 ISDC 流程，与广泛范围的下游工具和流程设计工具包（PDKs）兼容。评估结果显示，ISDC 相比工业级开源 HLS 工具可以减少 28.5% 的寄存器使用。