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Date: Tue, 28 Apr 2015 03:45:32 +0200
From: Agnieszka Bielec <bielecagnieszka8@...il.com>
To: john-dev@...ts.openwall.com
Subject: Re: [GSoC] John the Ripper support for PHC finalists

2015-04-27 3:20 GMT+02:00 Solar Designer <solar@...nwall.com>:

> What's your understanding as to why interleaving might help, beyond SIMD?

I modified php_mt_seed from 2-interleaving variables x and y into 2
functions where one function compute x and second y and I was
surprised to see that the speed decreased almost 2 times.
I modified also 2-interleaving to version where instructions with y
are in reverse order and the version when i removed y and put second x
and in the first case the speed was the same but in second case again
decreased.
It must be only that processor can execute 2 instructions at the same
time (where they are independent) and according to wikipedia there is
something like pipeline

thanks

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