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Re: floor on i386
- To: dewar at gnat dot com
- Subject: Re: floor on i386
- From: Frank Klemm <pfk at fuchs dot offl dot uni-jena dot de>
- Date: Thu, 27 Sep 2001 15:49:10 +0200
- >Received: (from pfk@localhost)by fuchs.offl.uni-jena.de (8.9.3/8.9.3/SuSE Linux 8.9.3-0.1) id PAA00566;Thu, 27 Sep 2001 15:49:10 +0200
- Cc: gcc at gcc dot gnu dot org
- References: <20010926231912.77A82F2B8E@nile.gnat.com>
On Wed, Sep 26, 2001 at 07:19:12PM -0400, dewar@gnat.com wrote:
>
> <<1st: rint() is faster, but also very slow (14x slower than optimum)
> 2nd: There's no subset of function to select another standard rounding
> model.
>
> Why isn't there a "rounding" function that *does* do the "optimal"
> function.
>
I posted a function collection. This function collection is not ANSI-C,
but with it it is possible to write performance code. You must be careful
while writing the code, but you are able to write the code.
Currently you can only write slow code. And slow code don't mean 70% of the
optimum performance, but something around 4%...7% of the optimum
performance (4% with floor, 7% with rint).
--
Frank Klemm