1. Nios II Custom Instruction Overview
2. Custom Instruction Hardware Interface
3. Custom Instruction Software Interface
4. Design Example: Cyclic Redundancy Check
5. Introduction to Nios® II Floating Point Custom Instructions
6. Nios II Floating Point Hardware 2 Component
7. Nios® II Floating Point Hardware (FPH1) Component
8. Document Revision History for Nios II Custom Instruction User Guide
4.1.1. Setting up the Environment for the CRC Example Design
4.1.2. Opening the Component Editor
4.1.3. Specifying the Custom Instruction Component Type
4.1.4. Displaying the Custom Instruction Block Symbol
4.1.5. Adding the CRC Custom Instruction HDL Files
4.1.6. Configuring the Custom Instruction Parameter Type
4.1.7. Setting Up the CRC Custom Instruction Interfaces
4.1.8. Configuring the Custom Instruction Signal Type
4.1.9. Saving and Adding the CRC Custom Instruction
4.1.10. Generating and Compiling the CRC Example System
6.1. Overview of the Floating Point Hardware 2 Component
6.2. Floating Point Hardware 2 IEEE 754 Compliance
6.3. IEEE 754 Exception Conditions with FPH2
6.4. Floating Point Hardware 2 Operations
6.5. Building the FPH2 Example Hardware
6.6. Building the FPH2 Example Software
6.7. FPH2 Implementation of GCC Options
6.8. Nios II FPH2 and the Newlib Library
6.9. C Macros for round(), fmins(), and fmaxs()
6.9. C Macros for round(), fmins(), and fmaxs()
Nios II GCC cannot reliably replace calls to the following newlib floating point functions with the equivalent custom instruction, even though it has –mcustom-<operation> command-line options and pragma support for them:
- round()
- fmins()
- fmaxs()
Instead, these custom instructions must be invoked directly using the __builtin_custom_* facility of GCC. system.h provides the required #define macros to invoke the custom instructions directly. The Nios II Software Build Tools automatically include this header file in your C source files.