Subject: Re: bridge: faster compare for link local addresses

From: Stephen Hemminger <[email-masked]>
Date: Tue, 13 Mar 2007 13:06:54 -0700

On Tue, 13 Mar 2007 12:39:54 -0700 (PDT)
David Miller <[email-masked]> wrote:

> From: Eric Dumazet <[email-masked]>
> Date: Tue, 13 Mar 2007 14:38:32 +0100
> 
> > But memcmp() has a strong semantic (in libc). memcmp(a, b, 6) should
> > do 6 byte compares and conditional branches, regardless of a/b
> > alignment.  Or use the x86 "rep cmpsb" instruction that basically
> > has the same cost.
> 
> Yep, that's the issue, gcc won't make the reductions necessary
> here to get it down to one comparison and one branch.

Also, for our usage we only care about equality, not greater/less than
return value.

-- 
Stephen Hemminger <[email-masked]>