wish: optimize (x > 0.) floating point comparison.

Charles M. Hannum root@ihack.net
Sat Sep 26 15:59:00 GMT 1998


> On Sat, Sep 26, 1998 at 10:03:54AM -0400, Charles M. Hannum wrote:
> > Don't let the 96-bit length fool you.  It's really the same format,
> > but with 16 bits wasted (for alignment purposes, I assume).
> 
> No it isn't the same, as the representable precision is different.
> For example, LDBL_MIN:
> 
>         i386    3.36210314311209350626e-4932
>         m68k    1.68105157155604675313e-4932

I hate to drag this out, but unfortunately your include files are
wrong.

Unlike the single- and double-precision formats, the
extended-precision format includes the leading 1 digit explicitly in
the mantissa.  This is the same on both i386 and m68k.

See section 1.5.2 of the `M68000 Family Programmer's Reference
Manual'.




More information about the Gcc mailing list