RIVERPlace：针对AQFP电路，采用高效重定时与增量布局修复互连违例
RIVERPlace: Repairing Interconnect Violations with Efficient Retiming and Incremental Placement for AQFP Circuits
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中文总结 AI 辅助
本文针对AQFP电路的可扩展性挑战，提出RIVERPlace框架，整合重定时与增量布局等技术修复互连违例，大幅降低布局开销、运行时间与延迟，实现完整开源AQFP基准套件的后布线时序闭合。
中文摘要 AI 辅助
绝热量子通量参量管（Adiabatic Quantum-Flux-Parametron, AQFP）具备接近兰道尔极限的能效，但因严格的路径平衡要求和有限的驱动强度，面临显著的可扩展性挑战。为解决该问题，本文提出RIVERPlace框架，整合长线流水线技术、重定时与增量布局，以最小化扰动修复互连违例。RIVERPlace首先应用感知布局的重定时技术修复违例，且不增加逻辑深度；当必须增加深度时，引入缓冲器切割插入（Buffer Cut Insertion, BCI），将违例修复建模为受限全局边选择问题，可归约为最大拓扑割问题，从而实现精确的多项式时间解决方案。BCI通过跨多行选择性地对边进行流水线处理，在修复互连违例的同时避免插入过多缓冲器。实验结果表明，RIVERPlace的性能始终优于现有AQFP布局方法：插入缓冲器的布局开销降低一个数量级以上，布局导致的深度减少3倍，电路面积减少2倍以上，运行时间减少一个数量级以上，延迟降低38%。这些改进实现了首个完整开源AQFP基准套件的后布线时序闭合实现，其中包括alu32等更大规模电路。
英文摘要
The Adiabatic Quantum-Flux-Parametron (AQFP) offers near-Landauer-limit energy efficiency but faces significant scalability challenges due to strict path balancing and limited drive strength. To address this, we propose RIVERPlace, a framework that integrates long-wire pipelining, retiming, and incremental placement to resolve interconnect violations with minimal disruption. RIVERPlace first applies placement-aware retiming to repair violations without increasing logical depth. When depth increases are necessary, we introduce Buffer Cut Insertion (BCI), which formulates violation resolution as a constrained global edge-selection problem reducible to a maximum topological cut, thereby enabling an exact polynomial-time solution. By selectively pipelining edges across multiple rows, BCI avoids excessive buffer insertion while resolving interconnect violations. Experimental results demonstrate that RIVERPlace consistently outperforms prior AQFP placement approaches, reducing placement overhead by more than an order of magnitude in inserted buffers, 3x in placement-induced depth, and over 2x in circuit area, while also reducing runtime by more than an order of magnitude and latency by 38%. These improvements enable the first post-routing, timing-closed implementations of the complete open-source AQFP benchmark suite, including larger circuits like alu32.
