Use the LiveBLocks array for SplitEditor::splitSingleBlocks() as well.

This fixes a bug where splitSingleBlocks() could split a live range after a
terminator instruction.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125237 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SplitKit.h b/lib/CodeGen/SplitKit.h
index 9294514..2b593d5 100644
--- a/lib/CodeGen/SplitKit.h
+++ b/lib/CodeGen/SplitKit.h
@@ -407,6 +407,10 @@
   /// Return the end of the live range.
   SlotIndex leaveIntvAfter(SlotIndex Idx);
 
+  /// leaveIntvBefore - Leave the open interval before the instruction at Idx.
+  /// Return the end of the live range.
+  SlotIndex leaveIntvBefore(SlotIndex Idx);
+
   /// leaveIntvAtTop - Leave the interval at the top of MBB.
   /// Add liveness from the MBB top to the copy.
   /// Return the end of the live range.