Re: [PATCH -v2] x86/hweight: Get rid of the special calling convention

From: Borislav Petkov
Date: Wed May 11 2016 - 08:48:09 EST


On Wed, May 11, 2016 at 01:24:09PM +0200, Peter Zijlstra wrote:
> Yeah, it might save a few cycles on the call, but given that most
> machines should have popcnt these days is it worth the hassle/cost of
> duplicating the lib/hweight.c magic in asm (and remember, twice, once
> for 32bit and once for 64bit) ?

Makes sense to me - we can do the funky cool stuff but considering the
fact that we have all the required bits already, I think we should do
the thunking game and be done with it.

I guess we're older, lazy and more realists now...

--
Regards/Gruss,
Boris.

SUSE Linux GmbH, GF: Felix ImendÃrffer, Jane Smithard, Graham Norton, HRB 21284 (AG NÃrnberg)
--