RegionInfo: Do not access a value that was just moved away

This fixes a regression introduced in r206310.

llvm-svn: 206328
diff --git a/llvm/lib/Analysis/RegionInfo.cpp b/llvm/lib/Analysis/RegionInfo.cpp
index 6f3b4c2..f0bf599 100644
--- a/llvm/lib/Analysis/RegionInfo.cpp
+++ b/llvm/lib/Analysis/RegionInfo.cpp
@@ -363,8 +363,8 @@
   std::vector<std::unique_ptr<Region>> Keep;
   for (iterator I = begin(), E = end(); I != E; ++I)
     if (SubRegion->contains(I->get()) && I->get() != SubRegion) {
-      SubRegion->children.push_back(std::move(*I));
       (*I)->parent = SubRegion;
+      SubRegion->children.push_back(std::move(*I));
     } else
       Keep.push_back(std::move(*I));