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Re: pp_add -> pp_i_add efficiency hack?

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From:
Jarkko Hietaniemi
Date:
November 14, 2000 08:30
Subject:
Re: pp_add -> pp_i_add efficiency hack?
Message ID:
20001114103006.A5026@chaos.wustl.edu
> OK. What does a scalar with IV and NV both OK mean?

I *think* it *should* mean that the cached IV and NV are both valid
*and* that there is no loss of precision: (IV)nv == iv && (NV)iv == nv.
Obviously, this doesn't seem to be the case.

> And what are the private flags actually used form?

No idea, sorry.

> There seems to be an implicit assumption that NV preserves IV always,

Yes, an unfortunate assumption.  I've tried shaking it once in a while
but too many tests have started failing (numconvert, it nothing else)
so I have always backed up.

> Am I right in thinking this is going to mean changing the 2nv and 2iv and 2uv
> code in sv.c?

Sounds familiar.

-- 
$jhi++; # http://www.iki.fi/jhi/
        # There is this special biologist word we use for 'stable'.
        # It is 'dead'. -- Jack Cohen

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