8.2i XST - Backward register balancing has no effect on carry chains

AR#	21766	Search For Another Answer
Topic	SW-XST
Last Updated	03/06/2008
Status	Active

Description

Keywords: rebalancing, 8.1i, 7.1i, 9.2, 10.1

Why does backward register balancing have no effect on carry chains?

Solution

Currently, XST cannot perform backward register balancing on a carry chain.

This is scheduled to be fixed in ISE 11.1.