On Fri, Nov 20, 2020 at 3:39 PM Maamoun TK maamoun.tk@googlemail.com wrote:
---------- Forwarded message --------- From: Maamoun TK maamoun.tk@googlemail.com Date: Thu, Nov 12, 2020 at 7:42 PM Subject: Re: [PowerPC] GCM optimization To: Niels Möller nisse@lysator.liu.se
On Thu, Nov 12, 2020 at 6:40 PM Niels Möller nisse@lysator.liu.se wrote:
I gave it a test run on gcc112 in the gcc compile farm, and speedup of gcm update seems to be 26 times(!) compared to the C version.
That's reasonable, I got similar speedup on more stable POWER instances than gcc compile farm.
Where would that documentation be published? In the Nettle manual, as some IBM white paper, or as a more-or-less academic paper, e.g., on arxiv? I will not be able to spend much time on writing, but I'd be happy to review.
I'll start writing the papers once I got more details from IBM, similar to intel documents, the document will be academic and practical at the same time, I'll dive into finite field equations to demonstrate how we get there as well as I'll add a practical example to clarify the preference of this method in addition to the expected speedup of this method. My intention that other crypto libraries could take advantage of this document or maybe be a starting point for further improvements to the algorithm so I'm checking if IBM would publish or approve such a document the same as intel.
You might want to ping Steven Munroe for feedback. He's an IBM old-timer who usually helps with implementations and technical editing. He has amazing knowledge of the POWER chips. He also has a GitHub with some nice POWER libraries. He has been CC'd.
Munroe also helped with https://github.com/noloader/POWER8-crypto/blob/master/power8-crypto.pdf. We wrote it because IBM documentation sucks. As far as I know there is no IBM documentation (expect a blog post that explains some of Andy Polyakov's OpenSSL code).
If you want to add information to the power8-crypto.pdf doc, then we can make you an author and collaborator for check-ins. As a collaborator, you won't have to waste time with patches and asking permission. Just edit the doc like a wiki page.
The power8-crypto.pdf is written in DocBook. The DocBook setup for Fedora and Ubuntu is in the document https://github.com/noloader/POWER8-crypto/blob/master/docbook.pdf.
Jeff