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Re: 16 year old bug

Matt Thomas <> wrote:
> On Aug 24, 2010, at 12:25 AM, Joerg Sonnenberger wrote:
> > On Mon, Aug 23, 2010 at 11:21:37PM -0400, Thor Lancelot Simon wrote:
> >> That's silly.  A bitmask is a bitmask, and there's nothing magical or
> >> difficult about masked compare.  Even the bug OpenBSD just fixed -- now
> >> that it basically doesn't matter any more -- is hardly complex nor is
> >> the fix so.
> > 
> > The issue with non-cont netmask is that it dramatically complicates the
> > lookup code. I'd say that at least 1/3 of the radix tree implementation
> > is just related to this "feature".
> Even worse, it's inefficient on newer hardware.  Most platforms have a
> count-leading operation which dramatically increases the lookups.  Also
> knowing the datatype and using datatype specific comparison speeds it
> up even more.
> I've been removing the use of radix and switching to ptree in the network
> rework.

Seems like there are good reasons to kill that code, especially the code
complexity.  I am also keen to see your ptree-based code.


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