Robert Dewar wrote:
I wrote:
Unfortunately, somewhere in the design process of the 8087 things went
wrong and the chip only handles 8 80-bit registers, not providing an
interrupt (or any other support) to an OS to fake the "virtual" 80-bit
registers.
This is nonsense. It is perfectly possible to extend the stack accurately
in memory. That is easily true on the 387, but was also true on the 8087
with just a little bit of fiddling (I know that some people thought this
was not possible, but they just did not look hard enough, the Alsys Ada
compiler for instance used a stack model for fpt, and dynamically extended
this stack in memory, so this is certainly possible).
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 ?
Given that most modern compilations on x86 hardware would use SSE, we
could at least comfort the users who do want to use the extra bits of
80-bit floating point land ...
It'll be the final nail in the coffing of PR/323 ...
--
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
