b % 32 could produce negative results. Therefore, the result
of the shift could be undefined values.

Bug: 
Change-Id: I6c2f7201df424735695aa01891d46523e3c5bd12
Reviewed-on: https://chromium-review.googlesource.com/759079
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49240}