From d9d0665d1c6b23412771fb2e6b2f00e383d7c892 Mon Sep 17 00:00:00 2001
From: Clement Courbet <courbet@google.com>
Date: Wed, 15 May 2019 08:21:18 +0000
Subject: [PATCH] [[DAGCombiner][NFC] Add a comment.

As suggested in D61846.

llvm-svn: 360755
---
 llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 8fe6f721584b..27da26446ee4 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/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))