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Re: Floating point comparison
Geoff Keating writes:
> > From: Ian Dall <ian@beware.dropbear.id.au>
> > Date: Fri, 6 Dec 2002 23:55:08 +1030
>
> > Geoff Keating writes:
> > > it didn't switch between GE and LT. Both branches are LT, it's just
> > > that one of them is reversed. It is your port that is interpreting a
> > > reversed LT branch as GE, which it shouldn't be doing.
> No. The last three lines do not 'make the transformation anyway'.
> They make a different transformation. You need to go away and think
> about how the transformations are different, and why the second
> transformation is correct no matter what the situation.
I understood they are different, but not why the second is "always
correct", or more precisely, I didn't understand whether it was the
ports responsibility to ensure it was safe. I guess you have answered
that, thanks.
Can you enlighten me as to the semantics of unorders comparisons?
I can think of two possibilities:
ULT means unordered or less than
ULT means use operations which don't raise excpetions on unordered.
or I suppose both.
Ian