GDB/libiberty support for IBM long double

Daniel Jacobowitz
Sun Dec 30 11:25:00 GMT 2007

On Fri, Dec 28, 2007 at 12:31:27PM -0200, Luis Machado wrote:
> On Fri, 2007-12-28 at 11:33 +0100, Andreas Schwab wrote:
> > That part of the function can be simplified quite a bit.  For example,
> > NaNs and infinities are already handled at this point, thus
> > special_exponent can only be true when the biased exponent is zero.
> Thanks for the feedback Andreas. How should we proceed to get code
> included on libiberty?

Post a patch to gcc-patches.  You may want to compare the libiberty
version with the gdb/doublest.c version, which is used otherwise;
I believe I introduced a use of the libiberty version for NaNs and
Joseph added some others for IBM split long double, but no other
platform uses them.  So problems are not unlikely.

I wonder if we really need to use floatformat_to_double instead of
floatformat_to_doublest for the split_half cases.  It seems like that
relies unnecessarily on the host double format.  Do things work better
if you use floatformat_to_doublest and DOUBLEST variables, instead
of floatformat_to_double (likewise floatformat_from_doublest)?

Daniel Jacobowitz

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