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[perl #116054] [PATCH] 3db6cbfc - SIPHASH is very slow on 32 bit x86

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From:
Tony Cook via RT
Date:
July 26, 2013 01:39
Subject:
[perl #116054] [PATCH] 3db6cbfc - SIPHASH is very slow on 32 bit x86
Message ID:
rt-3.6.HEAD-2552-1374802774-978.116054-15-0@perl.org
On Sun Dec 23 00:09:52 2012, bulk88 wrote:
> On Tue Dec 11 18:19:54 2012, bulk88 wrote:
> > This is a bug report for perl from bulk88@hotmail.com,
> > generated with the help of perlbug 1.39 running under perl 5.17.7.
> > 
> > 
> > -----------------------------------------------------------------
> > [Please describe your issue here]
> > 
> > summary: SIPHASH on 32 bit processors without native CPU 64 bit
> > integers
> > (such as 32 bit x86) is atleast an order of magnitude slower than one
> > at
> > a time hash
> 
> See attached patch. I tried it on VC 2003 32 bit Win32 Perl, no Quads,
> and on VC 2003 32 bit Win32 Perl, with Quads. Asm showed one_at_a_time
> being used on the with Quads Perl. I didn't do a make test on the Perls
> for this patch.

Perl no longer uses SIPHASH by default, even for 64-bit builds, so this
patch is obsolete.

I discussed this briefly in #p5p, and bulk88 would like the ticket kept
open for now.

Tony

---
via perlbug:  queue: perl5 status: open
https://rt.perl.org:443/rt3/Ticket/Display.html?id=116054

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