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Re: [lno] some cleanups for scev
Hello,
> > Perhaps you could write a more complete example, so that it can be seen
> > what you have in mind?
> >
>
> Yes, here it goes:
>
>
> Example1:
>
> loop_1
> a = phi (3, c)
> d = foo ()
> c = a + d
> endloop_1
>
> I still want to have a -> {3, +, d}
this makes a lot of code dependent on scev wrong. In particular
anything that tests "no_evolution_in_loop_p" will get wrong results
when testing such expressions. Similarly, detection of number of
iterations will get wrong results when expressions like this are
produced, since there is no indication that d may have different values
in different iterations and constant folding does not count with this.
What I would like to obtain for this expression is either
{3, +, chrec_top}, or chrec_top directly.
Or do you have any example where the usage of symbolic values would
actually be useful?
Zdenek