Best options for 64-bit FP on athlon?

[Brad Lucier]

> In the first sentence of your post, you wrote as if you wanted to set 
> the x87  53-bit rounding mode, as commercial Windows, and, apparently, 
> FreeBSD run-time libraries do.  AFAIK, you must either write the asm() 
> or consult the facilities of your library.  A few commercial compilers 
> for linux have an option -pc64, which sets 64-bit storage for spills, 
> but may not go so far as to set the corresponding precision.

Thanks for your note. I have no problem using _FPU_SETCW under Linux to
set the rounding precision on x87 instructions to 53 bit mantissas
(i.e., double precision). Jan has been telling about speed-ups using
the alternative FP architectures (SSE, MMX, whatever, I don't follow
them that closely), so I wanted to try them in this application, which
doesn't need the extended-precision operations of the x87.

Brad