Thorsten Froehlich <tho### [at] trfde> wrote:
> As I said before, the x86-64 ABI requires passing of floating-point 
> arguments in SSE registers on Windows, Linux and Mac OS X. You are free to 
> Google for gcc's implementation of the x86-64 ABI, which does exactly that. 
> Maybe try <http://www.google.com/search?q=site%3Agcc.gnu.org+x87+deprecated>

  I think that you both are confusing two things with each other.

  Compilers and software out there (including operating systems) are slowly
migrating to use SSE instead of the FPU, at least in the new 64-bit systems
(which is non-problematic because all amd/intel-based 64-bit systems do
have full SSE support).

  However, that is, for the umpteeth time, not what I'm objecting against.

  What I'm objecting against is the claim that operating systems running
on hardware *with* FPU are going to simply deliberately deny software
working access to the FPU.

  For the umpteeth time, that doesn't make any freaking sense. Is, for
example, the linux project going to say: "Sorry, you can't run the newest
kernel in a Pentium4 because we decided to drop support for programs using
the FPU"?

  It may be that in the future the kernel itself may not use the FPU at
all. That's, however, a completely different thing for it to drop support
for processors with an FPU and all software using it. It would, in fact,
completely go against one of the design principles of linux: To be as
portable as possible. Linux is one of the most portable systems out there
(only netbsd rivals it). Are they going to drop support for 90% of the
hardware out there for no good reason? I don't think so.

  When I ask about any concrete evidence that any operating system out
there is planning to actively deny access to the FPU, all I get is
material which talks about compilers migrating to SSE in 64-bit systems,
which has nothing to do with the issue.

-- 
                                                          - Warp

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