In article <383ADE3C.61F2BC9E@buckosoft.com> , Dick Balaska 
<dic### [at] buckosoftcom>  wrote:

> So if your code is using floats,
> they have to be converted to doubles before stuffing in the FPU (and
> converted back to float on the way out of the FPU).  So you lose precision
> and take a performance hit by using floats.

That is wrong! There is no time for conversion required, as it is a trivial
to "cut off" the exponent (reduce it from 11 to 8 bit) and the significant
(reducing it from 52 to 23 bit) when loading/storing them.
As a matter of fact, internally all current processors store floating-point
numbers as if they were doubles (or whatever other most precise internal
format they support). When performing the calculation as single-precision,
the other bits are just not taken into account.


     Thorsten

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