[fpc-devel] 64 Bit / 32 Bit

[Florian Klaempfl]

Jonas Maebe schrieb:
> 
> On 04 Oct 2007, at 13:24, Michael Schnell wrote:
> 
>>> It's probably better to directly introduce a longdouble type with
>>> longdouble (128 bit) semantics on all platforms. I don't think that
>>> emulating the almost nowhere supported 80 bit type does much good.
>> Is 128 bit supported by any hardware ?
> 
> Most hardware only directly supports up to 64 bit precision.

For the record: at least Sparc supports 128 Bit.

> 
>> 80 bit is and it's an IEEE standard format.
> 
> It's a fuzzy standard. The IEEE "double-extended precision" is only
> defined as ">= 79 bit", similarly to how "single-extended precision" is
> defined as ">= 43 bit".
> 
>> So I can't imagine why it is "nowhere supported"
> 
> Because the x86 is pretty much the only one to support it in hardware.
> Similarly, the m68k supported a 96 bit double-extended type which is
> supported (almost?) nowhere else, and it's just as IEEE standard as the
> x86's 80 bit floating point format. It just doesn't make sense to
> emulate such cpu-specific types on other platforms.
> 
> 
> Jonas
> _______________________________________________
> fpc-devel maillist  -  fpc-devel at lists.freepascal.org
> http://lists.freepascal.org/mailman/listinfo/fpc-devel