[ardour-dev] Denormalisation

[Ross Vandegrift]

On Tue, Apr 27, 2004 at 11:16:58AM +0300, Sampo Savolainen wrote:
> I've a few had problems which seem like denormalisation issues. In case
> someone reading this doesn't know what it is, you should read 
> http://phonophunk.phreakin.com/p4denormal.php . In short, it's got to do
> with processors handling very very very small floating point numbers very
> slowly.

This problem should be easily fixable in software.  According to IEEE
754, denormalizing results in loss of significance and starts a gradual
underflow. (there's a version at:
http://www.cs.berkeley.edu/~wkahan/ieee754status/IEEE754.PDF - I'm
looking at pages 2 and 15)

If you're just going to set a register that sets denormals to zero, why
not do it right and detect underflows?  When an underflow happens, just
stop banging the processor against the wall.

No fancy register required!

-- 
Ross Vandegrift
ross at willow.seitz.com

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