Re: [PATCH] wc: Add AVX2 optimization when counting only lines

[Pádraig Brady]

On 22/04/2021 19:54, Bernhard Voelker wrote:
> On 4/21/21 8:13 PM, Assaf Gordon wrote:
> > I'm attaching the patch (copied from the Github's pull-request),
> > hopefully we can continue the discussion here on the mailing list.
>
> Phew, so I see it's about getting 0-5x better performance versus decreased 
> maintainability
> due having yet another implementation of the counting in wc: we already have 
> different cases
> for multi-byte, for !count_chars etc.
> I'm not sure whether it's worth complicating the tool, and - as Rasmus 
> mentioned - the
> bottleneck is probably somewhere else.

Yes a fair point,
but the gains are worth it IMHO.
The awkward maintenance issue with separated flags in separate libs
is already developed and in place.
Going forward I think there will be a less homogenous landscape of CPUs,
so believe this will be of future benefit.

I plan to work on wc-avx2 this weekend.

cheers,
Pádraig