Desired Footprint by Technology Mapping Modification using a Genetic Algorithm in Odin II

Technology mapping is the transformation of a general Boolean logic network into a functional equivalent K-LUT network that can be implemented by the target FPGA device. Because an FPGA architecture is pre-determined, technology mapping is limited to the available resources. However, circuits can be optimized before the low-level synthesis phase. Odin II, part of the Verilog-to-routing project, is responsible for synthesis and elaboration. In the partial mapping phase of Odin II, some modifications are still possible for high-level modules—adder, multiplier—when there is no hard block available. When Odin II performs partial mapping to create soft logic, we can choose which implementation of a high-level module works best with respect to the desired goals: area versus speed. In this paper, we describe a method to modify circuit characteristics based on placement criteria. More specifically, after partial mapping circuit components during Verilog HDL code synthesis, there are still potential modifications in soft-logic circuit generation. We propose using a genetic algorithm during synthesis to adjust soft-logic circuit implementation in order to achieve the desired synthesis goal. We show that the approach provides promising results for a marginal cost in runtime.