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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97709 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelDAGToDAG.cpp b/lib/Target/X86/X86ISelDAGToDAG.cpp
index 08030e0..3fad8ad 100644
--- a/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -413,6 +413,7 @@
 }
 
 void X86DAGToDAGISel::PreprocessISelDAG() {
+  // OptForSize is used in pattern predicates that isel is matching.
   OptForSize = MF->getFunction()->hasFnAttr(Attribute::OptimizeForSize);
   
   for (SelectionDAG::allnodes_iterator I = CurDAG->allnodes_begin(),