Nios II Custom Instruction User Guide

ID 683242
Date 4/27/2020
Public
Document Table of Contents

6. Nios II Floating Point Hardware 2 Component

The FPH2 component provides low cycle count implementations of add, sub, multiply, and divide operations, and custom instruction implementations of additional floating point operations.

The FPH2 component is the preferred floating point implementation for the Nios II processor. Intel recommends FPH2 rather than the legacy FPH1 because it provides better performance and a smaller device footprint.

You should compile newlib from source code with individual –mcustom-<operation> options, selected to match your hardware configuration. This allows newlib to incorporate the benefits of all FPH2 operations that can be inferred by GCC. If you use the Nios II software build tools, the BSP generator takes care of this for you.