Hardware Implementation of the Exponent Based Computational Core for an Exchange-Correlation Potential Matrix Generation

摘要

This paper presents an FPGA implementation of a calculation module for a finite sum of the exponential products (orbital function). The module is composed of several specially designed floating-point modules which are, fully pipelined and optimized for high speed performance. The hardware implementation revealed significant speed-up for the finite sum of the exponential products calculation ranging from 2.5x to 20x in comparison to the CPU. The orbital function is a computationally critical part of the Hartree-Fock algorithm. The presented approach aims to increase the performance of the part of the quantum chemistry computational system by employing FPGA-based accelerator. Several issues are addressed such as an identification of proper code fragments, porting a part of the Hartree-Fock algorithm to FPGA, data precision adjustment and data transfer overheads. The authors' intention was also to make hardware application of the orbital function universal and easily attachable to different systems.