Re: [Qemu-devel] [PATCHv3 4/9] bitops: use vector algorithm to optimize find_next_bit()

[Eric Blake]

On 03/21/2013 09:57 AM, Peter Lieven wrote:
> this patch adds the usage of buffer_find_nonzero_offset()
> to skip large areas of zeroes.
> 
> compared to loop unrolling presented in an earlier
> patch this adds another 50% performance benefit for
> skipping large areas of zeroes. loop unrolling alone
> added close to 100% speedup.
> 
> Signed-off-by: Peter Lieven <address@hidden>
> ---
>  util/bitops.c |   22 +++++++++++++++++++---
>  1 file changed, 19 insertions(+), 3 deletions(-)

Reviewed-by: Eric Blake <address@hidden>

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org

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