Clean ups for loop deletion based on Chris' feedback.
Clean ups for loop deletion based on Chris' feedback.

Also, use SCEV to determine the trip count of the loop, which is more powerful
and accurate that Loop::getTripCount.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@51179 91177308-0d34-0410-b5e6-96231b3b80d8

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