RE: [PATCH v3 2/2] powerpc: add support for csum_add()

From: David Laight
Date: Wed May 27 2015 - 04:42:57 EST


From: Scott Wood
> Sent: 26 May 2015 20:43
...
> > I was thinking of all 64bit targets, not 32bit ones.
>
> Oh, you mean move it out of arch/powerpc? Sounds reasonable, but
> someone should probably check what the resulting code looks like on
> other common arches. OTOH, if we're going to modify non-arch code,
> that might be a good opportunity to implement Segher's suggestion and
> move to a 64-bit accumulator.

Or more likely: adding alternate 32bit words to different 64-bit
registers in order to reduce the dependency chains further.
I'm sure I've seen a version that does that somewhere.

David