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

llvm-svn: 45815

1 files changed, 8 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp b/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
index 80d3547e4b4..b4f50e19291 100644
--- a/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -309,7 +309,14 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock *mbb,
       // 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);