ePlace: Electrostatics based placement using Nesterov#039;s method

摘要

ePlace is a generalized analytic algorithm to handle large-scale standard-cell and mixed-size placement. We use a novel density function based on electrostatics to remove overlap and Nesterov's method to minimize the nonlinear cost. Steplength is estimated as the inverse of Lipschitz constant, which is determined by our dynamic prediction and backtracking method. An approximated preconditioner is proposed to resolve the difference between large macros and standard cells, while an annealing engine is devised to handle macro legalization followed by placement of standard cells. The above innovations are integrated into our placement prototype ePlace, which outperforms the leading-edge placers on respective standard-cell and mixed-size benchmark suites. Specifically, ePlace produces 2.83%, 4.59% and 7.13% shorter wirelength while runs 3.05×, 2.84× and 1.05× faster than BonnPlace, MAPLE and NTUplace3-unified in average of ISPD 2005, ISPD 2006 and MMS circuits, respectively.