RFC: fp printing speedup patch

[Paolo Carlini]

Paolo Carlini wrote:

>       So, if the dtoa code that you have moved is by and large 
> equivalent to that
>       present in v2 (it is, right?), the performance improvement you 
> have abtained
>       for "small" numbers (~3.5x) seems *way* too good, since we would 
> *largely*
>       outperform v2 as shipped with 2.96-99!

... hum, now I see that this can be easily explained considering that 
your performance
numbers are only for the formatting part not for the complete output 
(right?). If,
for instance, we suppose that in current mainline roughly half the total 
time is spent
for writing the buffer and half for formatting, everything would be 
consistent...

Paolo.