Re-commit 117518 and 117519 now that ARM MC test failures are out of the way.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117531 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.cpp b/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.cpp
index 0ffb4da..d34a52d 100644
--- a/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.cpp
+++ b/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.cpp
@@ -454,6 +454,9 @@
     return;
 
   unsigned DefIdx = Use->getOperand(OpIdx).getResNo();
+  if (Use->isMachineOpcode())
+    // Adjust the use operand index by num of defs.
+    OpIdx += TII->get(Use->getMachineOpcode()).getNumDefs();
   int Latency = TII->getOperandLatency(InstrItins, Def, DefIdx, Use, OpIdx);
   if (Latency >= 0)
     dep.setLatency(Latency);