[[DAGCombiner][NFC] Add a comment.

As suggested in D61846.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360755 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 8fe6f721584b97656ee084f3eae62dc646746b4e..27da26446ee470c3b7c934b1da53ad054c396f81 100644 (file)
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -19830,6 +19830,8 @@ bool DAGCombiner::isAlias(SDNode *Op0, SDNode *Op1) const {
       return false;
   }
 
+  // Try to prove that there is aliasing, or that there is no aliasing. Either
+  // way, we can return now. If nothing can be proved, proceed with more tests.
   bool IsAlias;
   if (BaseIndexOffset::computeAliasing(Op0, MUC0.NumBytes, Op1, MUC1.NumBytes,
                                        DAG, IsAlias))