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From: robert.corbett@sun.com
Newsgroups: comp.lang.fortran
Subject: Re: high-precision type
Date: 15 Dec 2005 00:13:42 -0800
Message-ID: <1134634422.351812.105920@f14g2000cwb.googlegroups.com>

> Any prospect of this feature appearing in cheap PC hardware
> in the near future?

No.  It is possible to build an FPU that implements a slow, but
much faster than software, version of quad using about 15%
more transistors than an FPU that implements just single and
double.  The problem is that such an FPU will be slower on
single and double than if quad were not supported.  No CPU
vendor would make such a tradeoff.  Implementing quad using
a separate FPU would avoid slowing single and double, but then
the number of additional transistors and wires needed makes it
impractical.  Cutting yields, and thus profits, for the sake of a
feature that has little use in general-purpose computing.
Games saved floating-point, but games don't need quad.

Bob Corbett


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