A Hierarchical Mixed Mode Placement Algorithm
分级的混合模式布局算法

A hierarchical automatic placement algorithm for mixed mode placement problem is presented. The so-called mixed mode is a combination of standard cell and macro block. The presented algorithm completes the placement in both block level and cell level. In block level, the random cells are firstly partitioned into soft blocks, then SP (sequence pair) based method is used to do block placement. In cell level, firstly, quadratic placement method is used to do inner placement within each soft block, then a placement improvement routine is done to the whole chip, and at last, a combined min-cut and enumeration based detailed placement procedure completes the final placement. The algorithm is tested on a set of circuits with different number of standard cells and macro blocks, and obtains satisfactory results.