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Re: merging for 3.4 (was Re: [Patch] Qualify min(), max() ...)



On Wed, 4 Dec 2002, Joe Buck wrote:

> Diego writes:
>
> > Whether tree SSA can be merged for 3.4 will depend on the state
> > of the branch by the time the Stage 1 window closes.  We are
> > making rapid progress but I would like to have the following in
> > place:
>
> [ stuff deleted ]
>
> > - Performance issues.  Right now the code generated by the tree
> >   optimizers is worse than the RTL optimizers.  This is to be
> >   expected at this stage and the whole tree optimization process
> >   can be disabled.  So, in principle I don't see a real problem
> >   with merging the infrastructure in.
>
> To me, this is critical.  GCC has, by some measures, slowly been getting
> worse and worse.  I believe in the tree-ssa concept, but I don't think
> that it should be accepted until it is a clear win.

It's only not because it doesn't have any optimizations enabled right now
besides CCP.
Even copy propagation isn't enabled by default right now.

Once copy propagation is enabled before CCP, and DCE is run after CCP, i
would expect it will be a clear win or no lose.

This should occur before 3.4 branches, unless lightning strikes all of us
dead.

Though if it doesn't, i'd say we should wait for 3.5.


--Dan


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