Don't use LiveVariables::VarInfo::DefInst.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45815 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index 80d3547..b4f50e1 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -309,7 +309,14 @@
       // are actually two values in the live interval.  Because of this we
       // need to take the LiveRegion that defines this register and split it
       // into two values.
-      unsigned DefIndex = getDefIndex(getInstructionIndex(vi.DefInst));
+      MachineRegisterInfo& MRI = mbb->getParent()->getRegInfo();
+      unsigned lowIndex = ~0U;
+      for (MachineRegisterInfo::def_iterator DI = MRI.def_begin(interval.reg),
+          DE = MRI.def_end(); DI != DE; ++DI)
+        if (getInstructionIndex(&*DI) < lowIndex)
+          lowIndex = getInstructionIndex(&*DI);
+      
+      unsigned DefIndex = getDefIndex(lowIndex);
       unsigned RedefIndex = getDefIndex(MIIdx);
 
       const LiveRange *OldLR = interval.getLiveRangeContaining(RedefIndex-1);