diff --git a/include/llvm/CodeGen/EdgeBundles.h b/include/llvm/CodeGen/EdgeBundles.h
index a1d29b1f02c..e8a4a2d2d89 100644
--- a/include/llvm/CodeGen/EdgeBundles.h
+++ b/include/llvm/CodeGen/EdgeBundles.h
@@ -46,7 +46,7 @@ public:
   unsigned getNumBundles() const { return EC.getNumClasses(); }
 
   /// getBlocks - Return an array of blocks that are connected to Bundle.
-  ArrayRef<unsigned> getBlocks(unsigned Bundle) { return Blocks[Bundle]; }
+  ArrayRef<unsigned> getBlocks(unsigned Bundle) const { return Blocks[Bundle]; }
 
   /// getMachineFunction - Return the last machine function computed.
   const MachineFunction *getMachineFunction() const { return MF; }
diff --git a/lib/CodeGen/SpillPlacement.cpp b/lib/CodeGen/SpillPlacement.cpp
index 6f33f5465ca..320128a999e 100644
--- a/lib/CodeGen/SpillPlacement.cpp
+++ b/lib/CodeGen/SpillPlacement.cpp
@@ -207,6 +207,17 @@ void SpillPlacement::activate(unsigned n) {
     return;
   ActiveNodes->set(n);
   nodes[n].clear();
+
+  // Very large bundles usually come from big switches, indirect branches,
+  // landing pads, or loops with many 'continue' statements. It is difficult to
+  // allocate registers when so many different blocks are involved.
+  //
+  // Give a small negative bias to large bundles such that 1/32 of the
+  // connected blocks need to be interested before we consider expanding the
+  // region through the bundle. This helps compile time by limiting the number
+  // of blocks visited and the number of links in the Hopfield network.
+  if (bundles->getBlocks(n).size() > 100)
+    nodes[n].Bias = -0.0625f;
 }