Skip identical instruction while calculating DBG_VALUE range.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105340 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 4a88545..eca94cb 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -2180,12 +2180,15 @@
     if (Processed.count(DV) != 0)
       continue;
 
+    const MachineInstr *PrevMI = MInsn;
     for (SmallVector<const MachineInstr *, 8>::iterator MI = I+1, 
            ME = DbgValues.end(); MI != ME; ++MI) {
       const MDNode *Var = 
         (*MI)->getOperand((*MI)->getNumOperands()-1).getMetadata();
-      if (Var == DV && isDbgValueInDefinedReg(*MI))
+      if (Var == DV && isDbgValueInDefinedReg(*MI) && 
+          !PrevMI->isIdenticalTo(*MI))
         MultipleValues.push_back(*MI);
+      PrevMI = *MI;
     }
 
     DbgScope *Scope = findDbgScope(MInsn);