RE: [PATCH v2 6/6] crypto: lib/sha - Combine round constants and message schedule

David Laight
2020-10-20T21:36:07Z

From: Arvind Sankar
> Sent: 20 October 2020 21:40
>
> Putting the round constants and the message schedule arrays together in
> one structure saves one register, which can be a significant benefit on
> register-constrained architectures. On x86-32 (tested on Broadwell
> Xeon), this gives a 10% performance benefit.

I'm actually stunned it makes that much difference.
The object code must be truly horrid (before and after).

There are probably other strange tweaks that give a similar
improvement.

David

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