[Patch] Use std::search in string::find

[Dhruv Matani]

*On Sat, 2004-06-12 at 15:31, Dhruv Matani wrote:
> Hi,
> 	You might also want to patch rfind, while you are at it. Included is a
> function rr_find, that attempts to emulate rfind, and also the timings
> for that function relative to string::rfind.

Here is a version that takes a const char*, size_type, and size_type, it
can be adopted easily if you feel it's fine.

> 
> 
> 
> 
> On Sat, 2004-06-12 at 01:46, Paolo Carlini wrote:
> > Hi,
> > 
> > the below is what I have implemented and tested on x86 and x86-64.
> > 
> > Interestingly for the new performance testcase the stripped code
> > size does *not* change. In mainline the total time changes as
> > follows on P4-2400 (always -O2):
> > 
> > current mainline x86
> > --------------------
> > 22.370u 0.000s 0:22.46 99.5%    0+0k 0+0io 166pf+0w
> > 
> > patched mainline x86
> > --------------------
> >  9.090u 0.000s 0:09.13 99.5%    0+0k 0+0io 168pf+0w
> > 
> > And as follows on x86-64-2GHz:
> > 
> > current mainline x86-64
> > -----------------------
> >  5.216u 0.000s 0:05.21 100.0%    0+0k 0+0io 0pf+0w
> > 
> > patched mainline x86-64
> > -----------------------
> >  4.743u 0.000s 0:04.74 100.0%    0+0k 0+0io 0pf+0w
> > 
> > In general, in these days often happens that on x86 current 3.4
> > gives better results than mainline. Indeed, this happens here
> > too for unpatched 3.4:
> > 
> > current 3.4 x86
> > ---------------
> > 14.920u 0.010s 0:15.03 99.3%    0+0k 0+0io 162pf+0w
> > 
> > patched 3.4 x86
> > ---------------
> >  9.450u 0.010s 0:09.51 99.4%    0+0k 0+0io 164pf+0w
> > 
> > All in all, the numbers speak in favor of this approach, and,
> > in case we really want to change the algorithm, we can just
> > improve the one provided generically in std::search.
> > 
> > I'll wait 'til tomorrow in case of comments.
> > 
-- 
        -Dhruv Matani.
http://www.geocities.com/dhruvbird/

Proud to be a Vegetarian.
http://www.vegetarianstarterkit.com/
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