From: Martin Willi <martin@strongswan.org>
Subject: Re: [PATCH v4] poly1305: generic C can be faster on chips with slow
 unaligned access
Date: Tue, 08 Nov 2016 08:52:39 +0100
Message-ID: <1478591559.5216.7.camel@strongswan.org>
References: <20161107191253.17998-1-Jason@zx2c4.com>
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> By using the unaligned access helpers, we drastically improve
> performance on small MIPS routers that have to go through the
> exception fix-up handler for these unaligned accesses.

I couldn't measure any slowdown here, so:

Acked-by: Martin Willi <martin@strongswan.org>

> -       dctx->s[0] = le32_to_cpuvp(key +  0);
> +       dctx->s[0] = get_unaligned_le32(key +  0);

Not sure what the exact alignment rules for key/iv are, but maybe we
want to replace the same function in chacha20_generic.c as well?

Martin