[RewriteStatepointsForGC] Strengthen assertions around liveness
[RewriteStatepointsForGC] Strengthen assertions around liveness

This is related to the issues addressed in 234651.  These assertions check the properties ensured by that change at the place of use.  Note that a similiar property is checked in checkBasicSSA, but without the reachability constraint.  Technically, the liveness would be correct to include unreachable values, but this would be problematic for actual relocation.



git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@234766 91177308-0d34-0410-b5e6-96231b3b80d8

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