[YLUG] Why is this so much faster on an Opteron?

[Robert Hulme]

> You've sort of touched on the problem with discovering SSE/SMD
> instructions mask the issue.
> P4 CPUs are notoriously bad at handling infinities, as well as NaNs and
> denormals.  Usually this isn't a huge problem, but on the first
> iteration, i == j == 0, so the division becomes "0.505/(0/1)", i.e
> infinity.  P4 CPUs are notoriously bad at handling infinities, as well
> as NaNs and denormals.  Once f == infinity, all your future divisions
> are also affected.
*facepalm*

*skulks away quietly*

-Rob

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