RRAM-based reconfigurable in-memory computing architecture with hybrid routing

Recent advances in resistive random-access memory (RRAM) evoke great interests in exploring alternative architectures. One interesting work is a RRAM-based reconfigurable architecture that provides superior programmbility and blurs the boundary between computation and storage, but long-distance routing becomes a performance bottleneck. However, long-distance routing in FPGA is efficiently implemented, but its fine-grained routing structure results in a large routing overhead. In this work, we present a RRAM-based reconfigurable architecture that addresses the routing challenges using hybrid routing, i.e., local and global routing by taking the best advantages of both architectures (prior RRAM-based and FPGA). We also provide a complete CAD framework that exhibits high parallelism and good scalability. Experimental results show that our reconfigurable architecture outperforms both architectures. It achieves a 46.88% reduction in delay and improves the energy efficiency by 66.23% compared with the prior RRAM-based architecture with a slightly increased area overhead. While comparing with FPGA, it reduces the delay and the routing overhead by 36.00% and 50.20%, respectively. Additionally, our CAD framework achieves 5.39x speedup, compared with the prior framework.