Compact Topology-aware Bus Routing for Design Regularity

In bus routing, if signal bits in a bus structure share a common routing topology, routability is increased by avoiding twisted patterns and variation immunity. The bus routing problem has become significantly important because of increasing complexity of bus structures for multi-chip-module, I/O pins, or on-chip memories in advanced technology. We present and evaluate a compact topology-aware bus routing method that can both compactly synthesize the routing topology of the bus and minimize design rule violations even in designs with high bus density and high track utilization. Our proposed method completed the bus routing in the runtime limit of the ICCAD-2018 contest and achieved 66% reduction in total cost compared with the winner of that contest.