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Re: [PATCH]: Fix places where we expect non-null loops in the loop array


On Dec 7, 2004, at 2:45 PM, Daniel Berlin wrote:
have two loops, and num_levels == 2, when one of the loop infos is NULL,
but hey, whatever. :)
So do I. Something seems to be out of synch. Zdenek?
This is normal for both the RTL and tree level, apparently (IE this is what has always happened when we remove loops).
It sounds like something that could be easily remedied tho... if you remove a loop, compress the remaining ones and decrement the number of levels. Or am I missing something about why we wouldnt want to do that.

I'm thinking somebody decided it's O(n^2) to do that (if we just omve the last loop into the array hole, we have to update the loop index, and i'm not sure if that is supposed to be invariant or not :P), and thus decided that doing this was better.
Who knows :)
I'm just guessing, it'd be nice to find out the real reasoning behind this design.

Are you sure there was a design? This looks like behavior you might easily
get by accident (i.e. a lurking bug).



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