crypt-dev - Re: alternative approach

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Date: Tue, 7 Jun 2011 04:22:21 +0400
From: Solar Designer <solar@...nwall.com>
To: crypt-dev@...ts.openwall.com
Subject: Re: alternative approach

Yuri -

I asked:
> > How large was the reduction?  Can you also try simple "a ^ b" (no mask)
> > and simple "a + b", and report the LUT counts for all four (original
> > full pcadd(), your "a ^ b ^ mask", and these two I suggested)?  These
> > numbers might give us some hints.

On Mon, Jun 06, 2011 at 08:10:27PM -0300, Yuri Gonzaga wrote:
> Ok. I have uploaded a pdf file reporting the 4 cases' results here:
> http://bit.ly/iLaZQB

This shows two things:

1. The smallest LUT count is for the original pcadd(), contrary to what
you had said.

2. All four LUT counts are a lot higher than those you had reported for
bflike.  Are they for something else?

Can you perhaps share the corresponding four pieces of code as well?

Thanks,

Alexander