[illumos-Developer] Floating-point formats supported on S390/S390x... / was: Re: Ugh... xdr_{float, double} problems

[Neale Ferguson]

Sol390 supports IEEE754 fp. The kernel, compilers and libraries all have the support. The compilers also support the decimal FP standard. No need to worry about converting to/from the IBM hex fp.

On Feb 1, 2011, at 10:26, "Roland Mainz" <roland.mainz at nrubsig.org> wrote:

> On Tue, Feb 1, 2011 at 12:34 AM, Garrett D'Amore <garrett at nexenta.com> wrote:
> [snip]
>> It sounds like all the main CPU targets support IEEE 754.  The only
>> reasonable (?) question IMO is S390.  Roland?  Neale?
> 
> I'm not sure whether Neale is subscribed here... CC:'ing him and Mike
> Cowlishaw as the experts on the (IBM) floating-point stuff.
> 
> AFAIK (Neale/Mike, please correct me if I am wrong) S390/S390x support
> both IEEE 754 floating point and the IBM floating points format. But
> I'm not sure what the Solaris S390 port supports or will support...
> this depends on the software (e.g.gcc, libm, kernel) and minimum
> hardware (e.g. newer IBM Z/Series machines even support the decimal
> floating-point parts of IEEE 754-2008 in hardware and the S390 port
> only runs on rather new hardware (and newer versions of the Hercules
> emulator) but Solaris libm has no support for that (yet) and I didn't
> remeber seeing any support for that in the S390 port) ...
> 
> BTW: Interesting question: Is there a way (e.g. helper function in gcc
> for S390/S390x) to convert between IBM and IEEE754 floating-point
> formats on the fly ?
> 
> ----
> 
> Bye,
> Roland
> 
> -- 
>   __ .  . __
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