On 9/14/2010 8:41 AM, Steve Kargl wrote:
gfc ifc
sqrtq 200 160 (ie, __float128 is XXX times slower than double)
sinq 100 6
cosq 150 10
asinhq 120 10
erfcq 150 6
on the same hardware. Note, gfc = gfortran, and ifc = ifort.
The question then becomes what are the algorithms that Intel uses
to compute the last four functions.
As far as I know, the algorithms in the Intel quad precision math
library are closely held, although you might learn something by objdump
or similar tools. I would be concerned that doing this myself would run
into conflicts with my employer, as my gcc paperwork will not be
reconfirmed by them.