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Re: [PATCH]: Fix places where we expect non-null loops in the loop array
Hello,
> >no, it is expected behavior. As for why I decided to do it this way --
> >so that the numbers of the loops do not change in the middle of an
> >optimization (so you can for example store some information for loops
> >in an array indexed by loop numbers). I do not think it is seriously
> >used anywhere (except perhaps for scev, that store loop numbers in
> >CHREC nodes).
>
> Okay, so, uh, guys, what do you want me to do?
> Make things ignore null loops (which is what everything does now)?
it seems to be the simplest choice to me.
> Invalidating the loop indexes by compression will screw over scev's cache,
> which will cause a performance regression at the expense of a few if's in
> the other code.
>
> I can of course, go through and figure out the new num_levels and depth,
> etc, without compressing the array.
loop->depth is always updated, so you do not have to go through everything to
get it. I do not know what num_levels is supposed to be (which very
likely means that it is not updated, and you would really have to go
over the loops and determine it).
Zdenek