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Re: Glibc on ppc built on i386




Geoff Keating wrote:

> You need to have all the functionality in the library available in
> both fpu and fpuless versions, including libm.  Soft-float does not
> mean programs will not need to do floating-point calculations; it just
> means that you need to write software that can perform them, instead
> of using hardware provided by IBM.  When you ask gcc for soft-float,
> it just tries to call the routines you provide instead of using the
> hardware.

The softfloat implementation is in libgcc.a. it gets included when making the final executable.libm would then use the default
values for ieee754 and it would work ?
As this library always is there I did not think of this as a softfloat library.

In a previous mail you mentioned some problem with pic and softfloat. What would that be?


> > I don't really have too wite new f an s_*.S files do I ?
>
> You may be able to just move the s_*.S files out of the way so that
> the libm-ieee754 routines get used, but you do need to write the fenv
> stuff.  Probably you will need to just write versions of the routines
> that don't actually do anything: they only support one rounding mode,
> they have no exceptions, and there is no floating-point environmental
> state to save or restore.  Of course, if you're using a comprehensive
> soft-float library, it will provide exceptions and/or rounding modes,
> and it would be nice to interface with these.
>

I'm planing on using the one with egcs no exception no rounding mode but then again iam not even going to use float. Also I have
looked at other targets and al only have one fenv.h file in the fpu directory. I thougt that if one configures with --without-fp
the make process dont even go into  the fpu directory and thus no fenv.h file needed for softfloat. I have looked at the make
files but I think they are quite hard to understand I'm mostly guessing.





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