1 files changed, 14 insertions, 5 deletions
diff --git a/polly/lib/Analysis/ScopDetection.cpp b/polly/lib/Analysis/ScopDetection.cpp
index 889d2989ee9..14f9e3e08de 100644
--- a/polly/lib/Analysis/ScopDetection.cpp
+++ b/polly/lib/Analysis/ScopDetection.cpp
@@ -402,11 +402,15 @@ bool ScopDetection::isValidBranch(BasicBlock &BB, BranchInst *BI,
 }
 
 bool ScopDetection::isValidCFG(BasicBlock &BB, bool IsLoopBranch,
+                               bool AllowUnreachable,
                                DetectionContext &Context) const {
   Region &CurRegion = Context.CurRegion;
 
   TerminatorInst *TI = BB.getTerminator();
 
+  if (AllowUnreachable && isa<UnreachableInst>(TI))
+    return true;
+
   // Return instructions are only valid if the region is the top level region.
   if (isa<ReturnInst>(TI) && !CurRegion.getExit() && TI->getNumOperands() == 0)
     return true;
@@ -768,7 +772,7 @@ bool ScopDetection::canUseISLTripCount(Loop *L,
   L->getLoopLatches(LoopControlBlocks);
   L->getExitingBlocks(LoopControlBlocks);
   for (BasicBlock *ControlBB : LoopControlBlocks) {
-    if (!isValidCFG(*ControlBB, true, Context))
+    if (!isValidCFG(*ControlBB, true, false, Context))
       return false;
   }
 
@@ -977,12 +981,17 @@ bool ScopDetection::allBlocksValid(DetectionContext &Context) const {
   }
 
   for (BasicBlock *BB : CurRegion.blocks()) {
-    // Do not check exception blocks as we will never include them in the SCoP.
-    if (isErrorBlock(*BB, CurRegion, *LI, *DT))
-      continue;
+    bool IsErrorBlock = isErrorBlock(*BB, CurRegion, *LI, *DT);
 
-    if (!isValidCFG(*BB, false, Context) && !KeepGoing)
+    // Also check exception blocks (and possibly register them as non-affine
+    // regions). Even though exception blocks are not modeled, we use them
+    // to forward-propagate domain constraints during ScopInfo construction.
+    if (!isValidCFG(*BB, false, IsErrorBlock, Context) && !KeepGoing)
       return false;
+
+    if (IsErrorBlock)
+      continue;
+
     for (BasicBlock::iterator I = BB->begin(), E = --BB->end(); I != E; ++I)
       if (!isValidInstruction(*I, Context) && !KeepGoing)
         return false;