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

From: David Laight
Date: Tue May 26 2015 - 10:26:00 EST


From: Scott Wood ...
> > I'd also have thought that the 64bit C version above would be generally 'good'.
>
> It doesn't generate the addc/addze sequence. At least with GCC 4.8.2,
> it does something like:
>
> mr tmp0, csum
> li tmp1, 0
> li tmp2, 0
> addc tmp3, addend, tmp0
> adde csum, tmp2, tmp1
> add csum, csum, tmp3

I was thinking of all 64bit targets, not 32bit ones.

David

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