From: Andi Kleen <ak@suse.de>
To: Akinobu Mita <mita@miraclelinux.com>
Subject: Re: [patch 14/44] generic hweight{64,32,16,8}()
Date: Wed, 1 Feb 2006 10:06:07 +0100
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On Wednesday 01 February 2006 10:02, Akinobu Mita wrote:

> +static inline unsigned int hweight32(unsigned int w)
> +{
> +        unsigned int res = (w & 0x55555555) + ((w >> 1) & 0x55555555);
> +        res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
> +        res = (res & 0x0F0F0F0F) + ((res >> 4) & 0x0F0F0F0F);
> +        res = (res & 0x00FF00FF) + ((res >> 8) & 0x00FF00FF);
> +        return (res & 0x0000FFFF) + ((res >> 16) & 0x0000FFFF);
> +}

How large are these functions on x86? Maybe it would be better to not inline them,
but put it into some C file out of line.

-Andi
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