Update live-in lists when splitting critical edges.

Fixes PR10814. Patch by Jan Sjödin!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141960 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MachineBasicBlock.cpp b/lib/CodeGen/MachineBasicBlock.cpp
index 8f0fb46..4c5fe4c 100644
--- a/lib/CodeGen/MachineBasicBlock.cpp
+++ b/lib/CodeGen/MachineBasicBlock.cpp
@@ -571,6 +571,11 @@
       if (i->getOperand(ni+1).getMBB() == this)
         i->getOperand(ni+1).setMBB(NMBB);
 
+  // Inherit live-ins from the successor
+  for (MachineBasicBlock::livein_iterator I = Succ->livein_begin(),
+	 E = Succ->livein_end(); I != E; ++I)
+    NMBB->addLiveIn(*I);
+
   // Update LiveVariables.
   if (LV) {
     // Restore kills of virtual registers that were killed by the terminators.