Pass an explicit operand number to addLiveIns.

Not all instructions define a virtual register in their first operand.
Specifically, INLINEASM has a different format.

<rdar://problem/12472811>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165721 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MachineTraceMetrics.cpp b/lib/CodeGen/MachineTraceMetrics.cpp
index b3abec7..9686b04 100644
--- a/lib/CodeGen/MachineTraceMetrics.cpp
+++ b/lib/CodeGen/MachineTraceMetrics.cpp
@@ -850,14 +850,14 @@
   return false;
 }
 
-/// Assuming that DefMI was used by Trace.back(), add it to the live-in lists
-/// of all the blocks in Trace. Stop when reaching the block that contains
-/// DefMI.
+/// Assuming that the virtual register defined by DefMI:DefOp was used by
+/// Trace.back(), add it to the live-in lists of all the blocks in Trace. Stop
+/// when reaching the block that contains DefMI.
 void MachineTraceMetrics::Ensemble::
-addLiveIns(const MachineInstr *DefMI,
+addLiveIns(const MachineInstr *DefMI, unsigned DefOp,
            ArrayRef<const MachineBasicBlock*> Trace) {
   assert(!Trace.empty() && "Trace should contain at least one block");
-  unsigned Reg = DefMI->getOperand(0).getReg();
+  unsigned Reg = DefMI->getOperand(DefOp).getReg();
   assert(TargetRegisterInfo::isVirtualRegister(Reg));
   const MachineBasicBlock *DefMBB = DefMI->getParent();
 
@@ -950,7 +950,7 @@
           DEBUG(dbgs() << "pred\t" << Height << '\t' << *PHI);
           if (pushDepHeight(Deps.front(), PHI, Height,
                             Heights, MTM.SchedModel, MTM.TII))
-            addLiveIns(Deps.front().DefMI, Stack);
+            addLiveIns(Deps.front().DefMI, Deps.front().DefOp, Stack);
         }
       }
     }
@@ -983,7 +983,7 @@
       // Update the required height of any virtual registers read by MI.
       for (unsigned i = 0, e = Deps.size(); i != e; ++i)
         if (pushDepHeight(Deps[i], MI, Cycle, Heights, MTM.SchedModel, MTM.TII))
-          addLiveIns(Deps[i].DefMI, Stack);
+          addLiveIns(Deps[i].DefMI, Deps[i].DefOp, Stack);
 
       InstrCycles &MICycles = Cycles[MI];
       MICycles.Height = Cycle;