Placement of VLSI Fragments Based on a Multilayered Approach

Abstract

The article is connected with solving one of the main problems of automated engineering design stage of electronic computing equipment of placement of VLSI fragments in a limited area of a construction. Placement of VLSI fragments is NP-hard. The paper tells about the multilayered approach to solving this problem. Description of the placement problem is given in this work. Definition of the problem of placement of VLSI fragments in a grate is formulated. New search architecture based on the multilayered approach is proposed. The main difference of the suggested approach is division of the search process into two stages. At each stage different methods are used. This approach gives an opportunity to vectorize the solving process and to make optimal and quasioptimal solutions in a time similar to iteration algorithm realization time. A simulation experiment was conducted through the example of test cases (benchmarks). Quality of placement based on the suggested approach is averagely 2 % higher than quality of known algorithms such as Capo 8.6, Feng Shui 2.0, Dragon 2.23 what indicates the effectiveness of the combined search. A number of conducted test and experiments showed the prospects of using this approach. The time complexity of the suggested algorithms is ≈O(nlogn) at the best case and –O(n³) at the worst one.