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Re: FWD: FLOATING-POINT CONSISTENCY, -FFLOAT-STORE, AND X86


On Fri, Dec 18, 1998 at 07:48:52PM +0000, Dave Love wrote:
> 
>  Marc> Back to the problem: I see a couple of functions in
>  Marc> bits/mathinline.h explicitly using long double, but I suspect
>  Marc> this is to workaround the "spilling vs. chop" problem when
>  Marc> these are spilled to memory.
> 
> If they're confined to the inlines, at least we could avoid them
> affecting Fortran, which would be nice (for some of us) to know.

The non-inline functions _seem_ to use float and double, respectively,
as intermediate storage. At least the ones in the libm-ieee754
directory.

The functions in libm-i386, though, are mostyl implemente dusing assembly,
so, naturally, you won't be able to see wether they use double or long double
(or more important: wether they depend on extended precision or not).

Since *most* functions just call i386 assembly equivalents, there should be
no rounding problems, but remember that I didn't say this ;)

This might make them immune against 64 bit rounding mode.

--
Happy New Year, I'll be away from 21. Dec to 7. Jan

      -----==-                                              |
      ----==-- _                                            |
      ---==---(_)__  __ ____  __       Marc Lehmann       +--
      --==---/ / _ \/ // /\ \/ /       pcg@goof.com       |e|
      -=====/_/_//_/\_,_/ /_/\_\                          --+
    The choice of a GNU generation                        |
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