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Re: pp_add -> pp_i_add efficiency hack?

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Jarkko Hietaniemi
December 3, 2000 16:08
Re: pp_add -> pp_i_add efficiency hack?
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On Sun, Dec 03, 2000 at 11:01:39PM +0000, Simon Cozens wrote:
> On Sun, Dec 03, 2000 at 09:47:59PM +0000, Nicholas Clark wrote:
> > Well, it would be if I sent it. I'm tired and making mistakes now.
> Without the patch:
> u=2.31  s=0.38  cu=134.63  cs=11.73  scripts=261  tests=15242
> With the patch:
> u=2.32  s=0.3  cu=135.14  cs=11.67  scripts=261  tests=15242
> Was it really worth it?

IIRC the "efficiency" comes into play in one of Nicholas' platforms
(ARM Linux?) where double math is really, *really*, slow, and staying
with integers if at all possible really pays off.

There's also the 'correctness' aspect.  If NVs smear your low order
bits when you need need them you might get fussy about it.

$jhi++; #
        # There is this special biologist word we use for 'stable'.
        # It is 'dead'. -- Jack Cohen

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