Remove a special case that doesn't seem necessary any longer.

Back when this exception was added, it was skipping a lot more code, but
now it just looks like a premature optimization.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170989 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MachineInstr.cpp b/lib/CodeGen/MachineInstr.cpp
index f6d8fd8..9521776 100644
--- a/lib/CodeGen/MachineInstr.cpp
+++ b/lib/CodeGen/MachineInstr.cpp
@@ -711,19 +711,8 @@
   untieRegOperand(OpNo);
   MachineRegisterInfo *RegInfo = getRegInfo();
 
-  // Special case removing the last one.
-  if (OpNo == getNumOperands()-1) {
-    // If needed, remove from the reg def/use list.
-    if (RegInfo && Operands.back().isReg() && Operands.back().isOnRegUseList())
-      RegInfo->removeRegOperandFromUseList(&Operands.back());
-
-    Operands.pop_back();
-    return;
-  }
-
-  // Otherwise, we are removing an interior operand.  If we have reginfo to
-  // update, remove all operands that will be shifted down from their reg lists,
-  // move everything down, then re-add them.
+  // If we have reginfo to update, remove all operands that will be shifted
+  // down from their reg lists, move everything down, then re-add them.
   if (RegInfo) {
     for (unsigned i = OpNo, e = getNumOperands(); i != e; ++i) {
       if (Operands[i].isReg())