Intel® Hyperflex™ Architecture High-Performance Design Handbook

ID 683353
Date 12/08/2023
Document Table of Contents Restructuring Loops

Loops are a primary target of restructuring techniques because loops fundamentally limit performance. A loop is a feedback path in a circuit. Some loops are simple and short, with a small amount of combinational logic on a feedback path. Other loops are very complex, potentially traveling through multiple registers before returning to the original register.

The Compiler never retimes registers into a loop, because adding a pipeline stage to a loop changes functionality. However, change your RTL manually to restructure loops to improve performance. Perform loop optimization after analyzing performance bottlenecks with Fast Forward compile. Also apply these techniques to any new RTL in your design.