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From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
Date:   Wed, 12 Sep 2018 20:16:37 +0200
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Subject: Re: [PATCH net-next v3 02/17] zinc: introduce minimal cryptography library
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Netdev <netdev@vger.kernel.org>,
        David Miller <davem@davemloft.net>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Andrew Lutomirski <luto@kernel.org>,
        Samuel Neves <sneves@dei.uc.pt>,
        Jean-Philippe Aumasson <jeanphilippe.aumasson@gmail.com>,
        Linux Crypto Mailing List <linux-crypto@vger.kernel.org>
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Hi Eric,

On Wed, Sep 12, 2018 at 12:08 AM Eric Biggers <ebiggers@kernel.org> wrote:
> I'd strongly prefer the assembly to be readable too.  Jason, I'm not sure if
> you've actually read through the asm from the OpenSSL implementations, but the
> generated .S files actually do lose a lot of semantic information that was in
> the original .pl scripts.

The thing to keep in mind is that the .S was not directly and blindly
generated from the .pl. We started with the output of the .pl, and
then, particularly in the case of x86_64, worked with it a lot, and
now it's something a bit different. We've definitely spent a lot of
time reading that assembly.

I'll see if I can improve the readability with some register name
remapping on ARM. No guarantees, but I'll play a bit and see if I can
make it a bit better.

Jason