Hierarchical Concurrent Congestion and Wirelength Estimation in the Presence of IP Blocks

With the increasing sophistication of circuits and specifically in the presence of IP blocks, new estimation methods are needed in the design flow of large-scale circuits. Up to now, a number of post-placement congestion estimation techniques in the presence of IP blocks have been presented. The authors propose a novel stochastic pre-placement approach for concurrent congestion and wirelength estimation using the Rent´s exponent of the circuit. The experiments illustrate that the proposed method can quickly and accurately estimate wirelength and congestion. Simulation results show that the average error of the proposed wirelength estimation technique is less than 7%. Moreover, it is shown that in presence of IP blocks using a congestion removal technique based on our congestion estimation method results in 12.8% decrease in overflow on average