Check whether the right most 16 bits are all-zero.

Change-Id: I13bb8856888cbabc19c1f9354048f05ff9e4aacb
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2983839Reviewed-by: Ji Qiu <qiuji@iscas.ac.cn>
Commit-Queue: Ji Qiu <qiuji@iscas.ac.cn>
Cr-Commit-Position: refs/heads/master@{#75343}