Re: C++ and inlining

[Richard Guenther <rguenth at tat dot physik dot uni-tuebingen dot de>]

Andrew Pinski wrote:
> > It seems the topic has to be raised again.  The problem is the same as
> > discussed during the last discussion - basically the used ought to have
> > more control over what gets inlined (or not).  I want to focus on _hints_
> > to the compiler, not forcing it, as that may be impossible in some
> > circumstances.
> >
> > So, in my case there is CFD using Expression Templates and, frankly, gcc
> > is lousy in optimizing the math kernel loops due to not doing enough
> > inlining inside the loops.
>
>
> I think it is better to wait untill the CFG inliner comes about so then inline
> optimizated functions and maybe this complaint will no longer be here
> and the use of leafify is no longer needed.

Ok, I knew this point would come up.  But I've been waiting for "new 
technology to fix the issue" since gcc 3.2, so, you don't have a point 
here.  Also there _will_ be cases automatic heuristics fail.  So the 
question is, do we want to add the ability to specify inlining hints to 
the compiler, other than the (limiting in functionality) inline keyword?

Oh - and, the obvious question, will the CFG inliner be available in gcc 
3.5?

Richard.