Direct mapping of RTL structures onto LUT-based FPGA's

Abstract

The problem of mapping synthesized RTL structures onto look-up table (LUT)-based field programmable gate arrays (FPGAs) is addressed in this paper. The key distinctive feature of this work is a novel approach to perform the mapping by utilizing the iterative nature of the data path components. The approach exploits the regularity of data path components by slicing the components and mapping slices of one or more connected components together. This is in contrast to other FPGA mapping techniques which start from Boolean networks. Both cost optimal and delay optimal mappings are supported. The objective in cost optimal mapping is to cover a given data path network with minimum number of CLBs. Similarly in delay optimal mapping, the objective is to reduce the number of CLB levels in the critical combinational logic paths. Implementation of these mapping techniques with LUT based FPGAs as target technology results in a significant reduction in cost (CLB count) and critical path delays (CLB levels).