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Re: Draft "Unsafe fp optimizations" project description.
- To: dewar at gnat dot com
- Subject: Re: Draft "Unsafe fp optimizations" project description.
- From: Toon Moene <toon at moene dot indiv dot nluug dot nl>
- Date: Sun, 05 Aug 2001 17:18:30 +0200
- CC: gcc at gcc dot gnu dot org, ross dot s at ihug dot co dot nz
- Organization: Moene Computational Physics, Maartensdijk, The Netherlands
- References: <20010805143640.8DFDCF2B79@nile.gnat.com>
dewar@gnat.com wrote:
> Of course, in practice the distribution of floating-point numbers seen
> in real programs is nothing like uniform.
Well, I wasn't ready to take on this problem, because it could even turn
an unbiased error into a biased one ...
> In addition, in many architectures, and in particular on the x86, you
> are using extra precision and range for intermediate computations, and
> in this case, the number of overflow cases is drastically reduced.
Good point - I didn't consider that possibility.
--
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