Timing driven force directed placement flow

Abstract

Techniques for placement of integrated circuit elements include global placement, detailed placement, timing closure, and routing. The integrated circuit is described by a netlist specifying interconnections of morphable devices. The detailed placement uses, for example, Simultaneous Dynamical Integration, wherein the morphable-devices correspond to nodes influenced by forces, including timing forces. The timing forces are derived, for example, from a timing graph; path delay; slack; and drive resistance of the elements. The timing closure uses timing-driven buffering and timing-driven resizing to reduce maximum delay and/or transition time, and/or to fix hold time. Nets having high capacitance and/or fanout, and timing critical nets are preferentially processed. Timing-driven buffering applies buffering solutions to segments of route trees, combines solutions of adjoining segments, and prunes sets of solutions. Timing-driven resizing morphably replaces selected elements with upsized versions thereof.