Re: What to remove after tree-ssa is merged?

[Michael Matz <matz at suse dot de>]

Hi,

On Wed, 4 Feb 2004, Richard Kenner wrote:

> Looking into a type, yes, but I'm not sure what you mean by "bounded array".

Hmm, in your example you used a type representing an array with bounds.

>     So in that example the P_E is used in expressions, so they could be
>     lowered to trees not containing P_E (this involves probably making
>     some element references more explicit).  
> 
> But you don't have the *object* to make it more explicit when it's
> inside the type.  That's the whole point: it applies to every *object*
> of the type.

Of course.  But somewhen you _do_ apply it to an object.  Otherwise it
wouldn't have any observable effect and you couldn't lower it to RTL.  
And then it can be equally well lowered to trees.

>     To that question you then mentioned P_E inside types, but they should only
>     matter for type comparing or in context of expressions AFAICS.  
> 
>     the latter can be done with the above frontend specific lowering.
> 
> No, because it has to be done by the code that computes sizes and offsets
> in the middle end.

Sure, all expressions involving any P_E recursively would have to be 
expanded in the frontend, including such expressions (probably by using 
temporaries in order not to have to lower the whole tree).  If that's 
feasible I don't know.


Ciao,
Michael.