From mboxrd@z Thu Jan  1 00:00:00 1970
From: Giuseppe Scrivano <gscrivano@gnu.org>
Subject: Re: Linus' sha1 is much faster!
Date: Mon, 17 Aug 2009 00:15:49 +0200
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To: Linus Torvalds <torvalds@linux-foundation.org>
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In-Reply-To: <alpine.LFD.2.01.0908161306340.3162@localhost.localdomain> (Linus
	Torvalds's message of "Sun, 16 Aug 2009 13:10:20 -0700 (PDT)")
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Linus Torvalds <torvalds@linux-foundation.org> writes:

> I pretty much can guarantee you that it improves things only because =
it=20
> makes gcc generate crap code, which then hides some of the P4 issues.
>
> I'd also suggest you try gcc-4.4, since that apparently fixes some of=
 the=20
> oddest spill issues.


Thanks for the hint.  I tried gcc-4.4 and it produces slower code than
4.3 on the gnulib SHA1 implementation and my patch makes it even more!

I noticed that on my machine your implementation is ~30-40% faster usin=
g
SHA_ROT for rol/ror instructions than inline assembly, at least with th=
e
test-case P=C3=A1draig wrote.  Am I the only one reporting it?

Cheers,
Giuseppe