Robert Dewar wrote:
Well, I haven't studied this to such a great detail because I (according
to Kahan) belong to the group of people who "don't care about floating
point accuracy because their code is so robust they can even run on
Cray's", but doesn't this mean that we can solve it in the compiler by
having its run time library provide this functionality ?
You are mixing issues, the issue of extra precision on the x86 has nothing
whatever with whether or not such values can be stored in memory (they can),
and Kahan's inaccurate impression that there is a problem in extending the
stack, if indeed you are quoting him accurately, is not relevant.
Hmmm, lets be careful here. In my original reply I said "I do not have
a link just right now", which means I might recall things incorrectly.
I have read accounts (in a distant past) that the original purpose of
the x87 stack of 80-bit floating point values was to have a cache on the
processor (initially 8 registers) and the rest supported by "the
operating system". That could of course well be the common run time
library.
If your experience is that such a support (of an indefinite number of
80-bit floating point registers) could easily be provided by the run
time library of <language> compiler, that indicates to me that GCC could
provide such support.
The new thing I learned from your mail is the above. If GCC can support
this, than we can properly solve PR/323. This is independent of whether
I recall the thing I read in the past correctly.
Hope this helps,
--
Toon Moene - e-mail: [EMAIL PROTECTED] - phone: +31 346 214290
Saturnushof 14, 3738 XG Maartensdijk, The Netherlands
A maintainer of GNU Fortran 95: http://gcc.gnu.org/fortran/
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Fortran & C
