Re: Ping: [PATCH v4] faster strlen on x64

[OndÅej BÃlka <neleai at seznam dot cz>]

On Thu, Mar 07, 2013 at 04:09:27PM +0100, Andreas Jaeger wrote:
> On 03/07/2013 09:38 AM, Dmitrieva Liubov wrote:
> >Hello.
> >
> >I've reproduced performance measurement using Ondrej benchmarks on the
> >IA CPUs the most important for us and can confirm that this patch is
> >fine.
> >It seems that this conversation was kept in private messages and
> >didn't get publicity.
> >I'm sorry for that.
> 
> Thanks for confirming that the patches are a real benefit - now
> let's get them in a good shape (readable)...
> 
> Andreas
> -- 
>  Andreas Jaeger aj@{suse.com,opensuse.org} Twitter/Identica: jaegerandi
>   SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany
>    GF: Jeff Hawn,Jennifer Guild,Felix Imendörffer,HRB16746 (AG Nürnberg)
>     GPG fingerprint = 93A3 365E CE47 B889 DF7F  FED1 389A 563C C272 A126

Here is new version as standalone and diff from previous.

I did one functional change: replace 64bit bsf by 32bit which is
definitely faster.

Rest are added comments.

  * sysdeps/x86_64/strlen.S: Replace with new SSE2 based
  implementation which is faster on all x86_64 architectures.
  Tested on AMD, Intel Nehalem, SNB, IVB.
  * sysdeps/x86_64/strnlen.S: Likewise.

  * sysdeps/x86_64/multiarch/Makefile (sysdep_routines):
  Remove all multiarch strlen and strnlen versions.
  * sysdeps/x86_64/multiarch/ifunc-impl-list.c: Update.
  Remove strlen and strnlen related parts.

  * sysdeps/x86_64/multiarch/strcat-sse2-unaligned.S: Update.
  Inline strlen part.
  * sysdeps/x86_64/multiarch/strcat-ssse3.S: Likewise.
	* sysdeps/x86_64/strcat.S: Add comment.

  * sysdeps/x86_64/multiarch/strlen.S: Remove file.
  * sysdeps/x86_64/multiarch/strlen-sse2-no-bsf.S: Likewise.
  * sysdeps/x86_64/multiarch/strlen-sse2-pminub.S: Likewise.
  * sysdeps/x86_64/multiarch/strlen-sse4.S: Likewise.
  * sysdeps/x86_64/multiarch/strnlen.S: Likewise.
  * sysdeps/x86_64/multiarch/strnlen-sse2-no-bsf.S: Likewise.

Attachment: 0001-Faster-strlen-on-x86-64.patch
Description: Text document

Attachment: comments.patch
Description: Text document