D pointers

Thiago Macieira thiago at kde.org
Sat Oct 1 16:00:38 BST 2005

Stephan Kulow wrote:
> - without inline, the price of d pointers are: one more malloc
>     (can only be spared in KDE 4.0 and is likely to return, so
>     it's a little price and there is no guarantee to be kept - so we
>     better optimize _with_ it already included) and the extra
>     indirection that a d pointer brings (this->member becomes
>     this->d->member). The latter is the real problem

For the first access only in each function or for non-optimised code.

The optimising compiler will very likely elect this->d to be cached in a 
register, just like this itself is.

As Simon pointed out, we can solve that by moving code to the Priv class 

  Thiago Macieira  -  thiago (AT) macieira.info - thiago (AT) kde.org
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