Update kill flags while rewriting instructions after splitting.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117959 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SplitKit.cpp b/lib/CodeGen/SplitKit.cpp
index 5b5b602..f8be7d4 100644
--- a/lib/CodeGen/SplitKit.cpp
+++ b/lib/CodeGen/SplitKit.cpp
@@ -822,6 +822,7 @@
   for (MachineRegisterInfo::reg_iterator RI = mri_.reg_begin(reg),
        RE = mri_.reg_end(); RI != RE;) {
     MachineOperand &MO = RI.getOperand();
+    unsigned OpNum = RI.getOperandNo();
     MachineInstr *MI = MO.getParent();
     ++RI;
     if (MI->isDebugValue()) {
@@ -844,6 +845,8 @@
     DEBUG(dbgs() << "  rewr BB#" << MI->getParent()->getNumber() << '\t'<< Idx);
     assert(LI && "No register was live at use");
     MO.setReg(LI->reg);
+    if (MO.isUse() && !MI->isRegTiedToDefOperand(OpNum))
+      MO.setIsKill(LI->killedAt(Idx.getDefIndex()));
     DEBUG(dbgs() << '\t' << *MI);
   }
 }