Re: [PATCH v3] powerpc: Implement csum_ipv6_magic in assembly

On Thu, May 24, 2018 at 10:18:44AM +0000, Christophe Leroy wrote:

On 05/24/2018 06:20 AM, Christophe LEROY wrote:

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Le 23/05/2018 à 20:34, Segher Boessenkool a écrit :

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On Tue, May 22, 2018 at 08:57:01AM +0200, Christophe Leroy wrote:

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The generic csum_ipv6_magic() generates a pretty bad result

<snip>

Please try with a more recent compiler, what you used is pretty ancient.
It's not like recent compilers do great on this either, but it's not
*that* bad anymore ;-)

Here is what I get with GCC 8.1
It doesn't look much better, does it ?

There are no more mfocrf, which is a big speedup.  Other than that it is
pretty lousy still, I totally agree.  This improvement happened quite a
while ago, it's fixed in GCC 6.


Segher