Understanding core2core optimisation pipeline

Joachim Breitner mail at joachim-breitner.de
Fri Oct 31 09:11:18 UTC 2014


Hi,

Am Freitag, den 31.10.2014, 10:48 +0200 schrieb Jan Stolarek:
> One more question about reading the demand analysis results:
> 
>   Str=DmdType <S,1*U>
> 
> Here the argument is demanded once. But what if I have:
> 
>   Str=DmdType <S,U>
> 
> Does the lack of `1*` imply that the argument is used many times?

no; these things tend to be always an approximation in one direction. So
you either know that it is used at most once, or both is possible.

Nothing goes wrong when treating something that is used once as if it is
used multiple times.

What would be the value of knowing that it is definitely used multiple
times?

Greetings,
Joachim

-- 
Joachim “nomeata” Breitner
  mail at joachim-breitner.dehttp://www.joachim-breitner.de/
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  Debian Developer: nomeata at debian.org

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