Multi-Strategy Layer Assignment Algorithm Considering Bus Timing Matching

Layer assignment stage affects the timing matching of the bus by controlling the level of bus net in the global routing stage.Therefore,a multi-strategy layer assignment algorithm considering bus timing matching is proposed.First,a network prioritization strategy based on wired network attributes is adopted to acquire a routing sequence that satisfies not only the wire lengths but also the bus deviation according to the different attribute characteristics of the network.Second,using the initial routing strategy based on the greedy strategy,every shortest route in the network being configured is selected from each routing process,which keeps networks inside similar buses to be of equal lengths whenever possible.Finally,a local adjustment strategy formulated based on the bus wire length is employed to rip and reroute the completed initial routing,so as to lengthen parts of the network to minimize the length discrepancy between the bus longest wired network.The algorithms run in a Linux environment with a 2.60 GHz CPU and 64 GB of RAM.The algorithm validation experiments use the test data from the ISPD competition,and the experimental results show the bus deviation generated by this algorithm is reduced by 23.5%,and it is possible to significantly optimize the bus timing matching effect.