25 Jun
2004
25 Jun
'04
8:42 p.m.
On Fri, 2004-06-25 at 13:49, Tim Blechmann wrote:
The definition of denormal is that the exponent is 0 so you will never
multiply a denormal by 1, only by 0. I'm not sure whether that would be
a denormal operation or not. It depends on the compiler.
Jan
I have a
denormal fix without a branch but you probably don't want to
see it ;-)
It's pretty simple, just OR the bits of the exponent together which
gives either
0 (denormal) or 1, typecast that to float, and then multiply the
original float by that (0.0 or 1.0). Voila, no branch, but it is
messy looking ;-)
there is one problem ... if you multiply the denormal number with the 1
or 0, you will probably have one denormal operation on the cpu instead
of a branch ... i don't know, that's worse ...
but definitely, some benchmarks would be useful for any denormal
flushing algorithm...