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float precision on AMD64
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Date: -- (:)
From: sejourne_kevin <sejourne_kevin@y...>
Subject: Re: [Caml-list] float precision on AMD64
Ville-Pertti Keinonen a écrit :
> sejourne_kevin wrote:
> 
>> Do you want to say that one small logical operation (' and ' or '
>> shift') after the evaluation of an expression ' float ' will be slower
>> than the management of it box?
> 
> 
> Shifting floats wouldn't make much sense, but you could just clear/set
> the tag bit (it would be the least significant bit of the mantissa).
> However, this would be insufficient if you wanted control over rounding
> (you could only have round-toward-zero).
> 
> Of course someone content with losing a bit of precision from the
> mantissa probably wouldn't care too much about rounding.
> 

The programs who works with floats in 32 bits shall also work with
floats in 64 bits without one bit from the mantissa, no?

So, what are we waiting for unbox the floats?
Historical reason(C code wrote that use the box representation of the
floats) ?


Kévin.