5 Mar
2010
5 Mar
'10
7:18 p.m.
On 03/05/2010 12:26 PM, Eric Blake wrote:
According to Chris Lalancette on 3/5/2010 10:03 AM:
+static int popcnt(char x) +{ + char count; + for (count = 0; x; count++) + x &= x-1; + return count; +}
Gnulib provides the count-one-bits module, which does this much more efficiently (via a gcc builtin, when available; otherwise without any branching in the assembly).
I knew this wasn't the most efficient way to do it, but performance here doesn't really matter. If gnulib has a module for it, though, I'll use that instead. Thanks, -- Chris Lalancette