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Re: rs6000 LDBL_MAX converts to infinity


On Wed, Mar 03, 2004 at 01:32:59PM -0300, Alexandre Oliva wrote:
> Even if the rounding turns out to be unnecessary, I'd still put it in
> as defensive programming.

Hmph.  Unnecessary code is bad code.

1) You start off with a correctly rounded 106 bit mantissa.
2) Subtract off bits 0 to 52, or bits 0 to 52 rounded up, depending on
   the value of bit 53.
3) Are there more than 53 bits remaining?  If not, there's no need for
   rounding.

-- 
Alan Modra
IBM OzLabs - Linux Technology Centre


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