Update a comment, now that tail duplication happens after other branch

folding optimizations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89109 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/BranchFolding.cpp b/lib/CodeGen/BranchFolding.cpp
index 1a2117b9123efb2b5dd2c58bbec046869df39586..9ed805174b4b6fbe9a27de95b393447e40df0637 100644 (file)
--- a/lib/CodeGen/BranchFolding.cpp
+++ b/lib/CodeGen/BranchFolding.cpp
@@ -1230,8 +1230,8 @@ ReoptimizeBlock:
     // If the previous block unconditionally falls through to this block and
     // this block has no other predecessors, move the contents of this block
     // into the prior block. This doesn't usually happen when SimplifyCFG
-    // has been used, but it can happen if tail duplication eliminates all the
-    // non-branch predecessors of a block leaving only the fall-through edge.
+    // has been used, but it can happen if tail merging splits a fall-through
+    // predecessor of a block.
     // This has to check PrevBB->succ_size() because EH edges are ignored by
     // AnalyzeBranch.
     if (PriorCond.empty() && !PriorTBB && MBB->pred_size() == 1 &&