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Re: [sa]: Revert partial def stuff, use fake variables instead


Hello,

> >>>which seems terribly wrong to me.  Why should I need to change anything
> >>>so complicated, when I did not make any change that should affect
> >>>results of alias analysis?
> >>>
> >>You *have* changed the results of alias analysis.  You are introducing a
> >>new pointer, assigning it a new address and dereferencing it.
> >
> >and what?  I am accessing exactly the same location in memory, so from
> >the point of *results* of the alias analysis nothing changes.
> >
> Yes, but you need to keep the data structures up to date to say this, or 
> else how do we know this?

sure.  I just say our datastructures are unnecesarily complicated to use
and extend.

> >Yes, if the alias analysis is rerun afterwards, it needs to know about
> >things like pointers and such, internally.  But the results of the alias
> >analysis are not affected by the way addresses are expressed, and having
> >to perform magic just to keep the results the same does not seem right
> >to me.
> 
> What exactly are you proposing you should have to do in order for 
> everything else to know you haven't changed anything?

See my previous mail to Diego for concrete proposal (if it is too hard
to understand, I will prepare a complete patch in the evening; it should
not take too much time).

Zdenek


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