Index: lib/Analysis/ScopBuilder.cpp
===================================================================
--- lib/Analysis/ScopBuilder.cpp
+++ lib/Analysis/ScopBuilder.cpp
@@ -894,12 +894,14 @@
     return;
 
   // PHINodes in the SCoP region's exit block are also uses to be checked.
-  for (auto &Inst : *S->getRegion().getExit()) {
-    if (!isa<PHINode>(Inst))
-      break;
+  if (!S->getRegion().isTopLevelRegion()) {
+    for (auto &Inst : *S->getRegion().getExit()) {
+      if (!isa<PHINode>(Inst))
+        break;
 
-    for (auto &Op : Inst.operands())
-      verifyUse(S, Op, LI);
+      for (auto &Op : Inst.operands())
+        verifyUse(S, Op, LI);
+    }
   }
 }
 #endif
@@ -917,7 +919,7 @@
   // To handle these PHI nodes later we will now model their operands as scalar
   // accesses. Note that we do not model anything in the exit block if we have
   // an exiting block in the region, as there will not be any splitting later.
-  if (!scop->hasSingleExitEdge())
+  if (!R.isTopLevelRegion() && !scop->hasSingleExitEdge())
     buildAccessFunctions(*R.getExit(), nullptr,
                          /* IsExitBlock */ true);
 
Index: lib/Analysis/ScopDetection.cpp
===================================================================
--- lib/Analysis/ScopDetection.cpp
+++ lib/Analysis/ScopDetection.cpp
@@ -578,7 +578,7 @@
     return true;
 
   // Return instructions are only valid if the region is the top level region.
-  if (isa<ReturnInst>(TI) && !CurRegion.getExit() && TI->getNumOperands() == 0)
+  if (isa<ReturnInst>(TI) && CurRegion.isTopLevelRegion())
     return true;
 
   Value *Condition = getConditionFromTerminator(TI);
@@ -1485,13 +1485,14 @@
 
   DEBUG(dbgs() << "Checking region: " << CurRegion.getNameStr() << "\n\t");
 
-  if (CurRegion.isTopLevelRegion()) {
+  if (!AllowFullFunction && CurRegion.isTopLevelRegion()) {
     DEBUG(dbgs() << "Top level region is invalid\n");
     return false;
   }
 
   DebugLoc DbgLoc;
-  if (isa<UnreachableInst>(CurRegion.getExit()->getTerminator())) {
+  if (CurRegion.getExit() &&
+      isa<UnreachableInst>(CurRegion.getExit()->getTerminator())) {
     DEBUG(dbgs() << "Unreachable in exit\n");
     return invalid<ReportUnreachableInExit>(Context, /*Assert=*/true,
                                             CurRegion.getExit(), DbgLoc);
Index: lib/Support/ScopHelper.cpp
===================================================================
--- lib/Support/ScopHelper.cpp
+++ lib/Support/ScopHelper.cpp
@@ -380,9 +380,15 @@
   // Basic blocks that are always executed are not considered error blocks,
   // as their execution can not be a rare event.
   bool DominatesAllPredecessors = true;
-  for (auto Pred : predecessors(R.getExit()))
-    if (R.contains(Pred) && !DT.dominates(&BB, Pred))
-      DominatesAllPredecessors = false;
+  if (R.isTopLevelRegion()) {
+    for (BasicBlock &I : *R.getEntry()->getParent())
+      if (isa<ReturnInst>(I.getTerminator()) && !DT.dominates(&BB, &I))
+        DominatesAllPredecessors = false;
+  } else {
+    for (auto Pred : predecessors(R.getExit()))
+      if (R.contains(Pred) && !DT.dominates(&BB, Pred))
+        DominatesAllPredecessors = false;
+  }
 
   if (DominatesAllPredecessors)
     return false;