Graph-Based Logic Bit Slicing for Datapath-Aware Placement
Journal
Design Automation Conference
Journal Volume
Part 128280
Date Issued
2017
Author(s)
Abstract
Extracting similar datapath bit slices which handle highly parallel bit operations can help a modern placer to obtain better solutions for datapath-oriented designs. A current state-of-The-Art datapath bit slicing method achieves the best extraction results using a network-flow-based algorithm. However, this work has two major drawbacks: (1) it extracts only a limited number of bit slices for datapaths with different I/O widths, which are commonly seen in real designs, and (2) it does not consider bit-slice similarity, which is an important feature for placement considering datapaths. To remedy these drawbacks, we present (1) a balanced bipartite edge-cover algorithm to fully slice a datapath with different I/O widths, and (2) a simulated annealing scheme to further improve bit-slice similarity, while maintaining fully-sliced structures. Compared with the state-of-The-Art work, experimental results show that our slicing algorithm extracts more bit slices with similar structures, and helps a leading academic placer achieve averagely 5% smaller routed wirelength. The results also validate the high correlation between datapaths and structure regularity/similarity.
Type
conference paper