when checking if we should move a split edge block outside of a loop, check the presplit pred, not the post-split pred.  This was causing us to make the wrong decision in some cases, leaving the critical edge block in the loop.
when checking if we should move a split edge block outside of a loop,
check the presplit pred, not the post-split pred.  This was causing us
to make the wrong decision in some cases, leaving the critical edge block
in the loop.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@23601 91177308-0d34-0410-b5e6-96231b3b80d8

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