VLIW coprocessor for IEEE-754 quadruple-precision elementary functions

Abstract

In this article, a unified VLIW coprocessor, based on a common group of atomic operation units, for Quad arithmetic and elementary functions (QP_VELP) is presented. The explicitly parallel scheme of VLIW instruction and Estrin's evaluation scheme for polynomials are used to improve the performance. A two-level VLIW instruction RAM scheme is introduced to achieve high scalability and customizability, even for more complex key program kernels. Finally, the Quad arithmetic accelerator (QAA) with the QP_VELP array is implemented on ASIC. Compared with hyper-thread software implementation on an Intel Xeon E5620, QAA with 8 QP_VELP units achieves improvement by a factor of 18X.