diff --git a/lib/CodeGen/MachineInstr.cpp b/lib/CodeGen/MachineInstr.cpp
index ff32a66..52a9096 100644
--- a/lib/CodeGen/MachineInstr.cpp
+++ b/lib/CodeGen/MachineInstr.cpp
@@ -900,6 +900,16 @@
   return nextMI != Parent->instr_end() && nextMI->isInsideBundle();
 }
 
+MachineInstr* MachineInstr::getBundleStart() {
+  if (!isInsideBundle())
+    return this;
+  MachineBasicBlock::reverse_instr_iterator MII(this);
+  --MII;
+  while (MII->isInsideBundle())
+    --MII;
+  return &*MII;
+}
+
 bool MachineInstr::isStackAligningInlineAsm() const {
   if (isInlineAsm()) {
     unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();