ref: b44d75aa4e97e9264e585712a8ec5fa757b645ec
parent: b7f192eea34e0bd36abcd457333ab37eb221789f
author: Simon Tatham <anakin@pobox.com>
date: Sat Oct 22 12:38:15 EDT 2005
Noticed recently that bitcount16() isn't 16-bit clean due to signed shift right. It doesn't actually matter in the current code since the input word only ever uses the bottom 9 bits, but if I ever extended Mines to work in a triangular grid then all 16 bits might be required. Fix this now, while I'm cleaning things up, so that it won't bite me unexpectedly in future. [originally from svn r6415]