Bradley Lucier wrote:
>> While
>> it is possible to perform IEEE-754 double precision arithmetic
>> correctly on the IA32 architecture by writing every intermediate
>> result to memory,
>
>
> This is not sufficient to simulate double x double -> double
> operations---pre- and post-scalings, as well as setting the mantissa
> precision to 53 bits, are necessary to eliminate double rounding and  to
> compute possible denormal results correctly.

Yes. However, storing to memory solves the problem of writing (in C):

   double x = some expresion;
   double y = an identical expression;

and then finding that x != y because one variable was spilled to memory
and the other was held in a FPU register.

Regards,

Alan
--
Dr Alan Watson
Centro de Radioastronomía y Astrofísica
Universidad Astronómico Nacional de México