Index: lib/CodeGen/RegAllocGreedy.cpp
===================================================================
--- lib/CodeGen/RegAllocGreedy.cpp
+++ lib/CodeGen/RegAllocGreedy.cpp
@@ -1042,6 +1042,7 @@
   unsigned Visited = 0;
 #endif
 
+  unsigned j = 0;
   for (;;) {
     ArrayRef<unsigned> NewBundles = SpillPlacer->getRecentPositive();
     // Find new through blocks in the periphery of PrefRegBundles.
@@ -1063,7 +1064,7 @@
       }
     }
     // Any new blocks to add?
-    if (ActiveBlocks.size() == AddedTo)
+    if (ActiveBlocks.size() == AddedTo || j++ > 16)
       break;
 
     // Compute through constraints from the interference, or assume that all