Automatic datapath tile placement and routing

We report the very first fully automatic datapath tile layout flow. We subdivided the placement process into two steps: a global placement step using simulated annealing, and a new detailed placement step based on extensive modifications we made to the O-tree algorithm. The modifications have enabled the extended O-tree algorithm to handle the rectilinearly shaped transistor chains and gates common in datapath tile layout. We show that datapath tiles can be placed and routed automatically at the transistor level or at the mixed transistor/gate level, achieving results for the very first time that are competitive to those obtained manually by a skilled designer.