SKB-tree: a Fixed-Outline Driven Representation for Modern Floorplanning Problems

• Main Authors: Peng-Yi Liu, 劉�m鎰
• Other Authors: Jai-Ming Lin
• Format: Others
• Language: en_US
• Online Access: http://ndltd.ncl.edu.tw/handle/12655279710590866679

碩士 === 國立成功大學 === 電機工程學系碩博士班 === 97 === In this thesis, we propose an SKB-tree representation for non-slicing floorplanning. Since SKB-tree dynamically allocates regions for a set of blocks, all blocks can be placed into a specify outline for each solution, which makes it become a suitable representation for dealing with the fixed-outline constraint. More importantly, because it does not need to add an additional term in the cost function for the constraint, it can get better results than other representations. Due to this good property, we also use it to deal with the voltage-island driven floorplanning. In order to save power routing resource, simplify power planning, and reduce IR Drop, we constrain blocks of the same voltage to be placed into a continuous locations unlike most works do not have these constraints. Experimental results show the promise of SKB-tree. For the fixed-outeline constraint with the aspect ratio 1:1, SKB-tree achieved average improvements in wirelength of 39.8%, 49.4%, 25.6%, and 18.4% better than A-FP, Parquet 4.0, ZDS, and SAFFOA, respectively. Compared to the floorplans with other aspect ratios, our method is also better than A-FP and SAFFOA. For voltage island driven floorplanning, SKB-tree can also take 14.7% and 18.5% less power consumption and wirelength than Ma and Young [23].