Fix comment.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60592 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index 18ee27b..31b300a 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -1800,7 +1800,7 @@
   // Spill slot weight.
   SSWeight = 0.0f;
 
-  // Each bit specify whether it a spill is required in the MBB.
+  // Each bit specify whether a spill is required in the MBB.
   BitVector SpillMBBs(mf_->getNumBlockIDs());
   DenseMap<unsigned, std::vector<SRInfo> > SpillIdxes;
   BitVector RestoreMBBs(mf_->getNumBlockIDs());