diff --git a/llvm/lib/CodeGen/CalcSpillWeights.cpp b/llvm/lib/CodeGen/CalcSpillWeights.cpp
--- a/llvm/lib/CodeGen/CalcSpillWeights.cpp
+++ b/llvm/lib/CodeGen/CalcSpillWeights.cpp
@@ -203,8 +203,8 @@
   };
   std::set<CopyHint> CopyHints;
 
-  for (MachineRegisterInfo::reg_instr_iterator
-       I = mri.reg_instr_begin(li.reg), E = mri.reg_instr_end();
+  for (MachineRegisterInfo::reg_instr_nodbg_iterator
+       I = mri.reg_instr_nodbg_begin(li.reg), E = mri.reg_instr_nodbg_end();
        I != E; ) {
     MachineInstr *mi = &*(I++);
 
@@ -215,7 +215,7 @@
       continue;
 
     numInstr++;
-    if (mi->isIdentityCopy() || mi->isImplicitDef() || mi->isDebugInstr())
+    if (mi->isIdentityCopy() || mi->isImplicitDef())
       continue;
     if (!visited.insert(mi).second)
       continue;