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Re: [tree-ssa] Removal of gotos from cfg based ir


On Fri, 2003-11-14 at 16:38, Jan Hubicka wrote:
> > On Fri, 2003-11-14 at 15:51, Jan Hubicka wrote:

> > 
> > Bottom line is Im just trying to find good justifiable reasons why we
> > have to keep the CFG intact throughout compilation phases using
> > different ILs, and that we should modify the IL to do this.
> 
> The reason is to give mechanizm to pass control flow specific
> infomration for optimizers (like the profile).

> Of course with non-optimizing copilation it makes less sense, but given
> the complexity of our code generation backend we don't want to do too
> much code duplication when it does not save us any significant amount of
> cycles.  But in my eyes, we should make GCC optimizer friendly, while
> trying to keep nonoptimizing compilation fast, not making GCC
> non-optimizing friendly making optimizers dificult.
> 

I dont think we are making optimization any more difficult because we
create a new CFG when we translate from one IL to another IL. I was
never suggesting we prefer non-optimizing over optimizing. I'm sorry I
ever suggested anything about -O0 :-)

We have the same goals.  Simple is best, code duplication is bad, etc
etc.

The bottom line is you want to do this in order to pass control flow
specific information  from one IL to another, and you think that
maintaining the same CFG across different ILs is a better solution than
annotating the exisiting IL with the information and building a new CFG
when the translation is done.

correct?

Andrew


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