Obstacle-avoiding rectilinear Steiner tree construction in sequential and parallel approach

A heuristic for constructing a rectilinear Steiner tree by reusing routing resources over obstacles

“…The programs run sequentially on one processor. We conduct our experiments on 22 commonly used benchmark circuits from the literature on conventional OARSMT [5,[17][18][19][20][21]. We use a percentage relative improvement, as shown in Eq.…”

“…In previous studies, the RSMT, OARSMT, and LRSMT problems were usually transformed into the Steiner tree problem in graphs (GSTP) [2,5,6,8,[16][17][18][19][20][21]. A two-phase scheme for connecting a multi-pin net is adopted by these algorithms.…”

“…In the second phase, the scheme employs an exact or heuristic algorithm for the GSTP problem. The constraints of OARSMT [5,[16][17][18][19][20][21] and LRSMT [6,8] Thus, the extended Hanan grid adopted in [6,10]. Nevertheless, the quadratic size of the grid slows down the construction of Steiner trees.…”

A critical net reshape-router for high-performance VLSI layout design

“…The decision step outputs wi or wo on the routing area, i.e. if Maze_Router [6] successfully finds wi, then wi is output by Set_Wire, while wo is output otherwise. Fig.3-2 explains the steps of Critical net reshape router for a net with three pins of A, B and C with the routing area as the boundary.…”

“…Firstly, it calculates RMST of the critical net roughly, and then puts the restricted area by widening it (WRMST). Then, it applies a multi-layer maze router [6] to find the almost RMST shape route. According to the experimental results, our router obtained almost the same shape as RMST and achieves about 4.4% to 9.5% less wire length on average than the original wire-length.…”