[llvm] NFC: Add a comment indicating UpdateAnalysisInformation invalidates DFS Numbering (PR #91252)

[via llvm-commits]

https://github.com/hiraditya updated https://github.com/llvm/llvm-project/pull/91252

>From 5da07d03d7932b8ecb00f114041cdad3a99905ae Mon Sep 17 00:00:00 2001
From: AdityaK <hiraditya at msn.com>
Date: Mon, 6 May 2024 11:38:53 -0700
Subject: [PATCH] NFC: Add a comment indicating UpdateAnalysisInformation
 invalidates DFS Numbering

---
 llvm/lib/Transforms/Utils/BasicBlockUtils.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
index b9ed077b660dd..462283c0bfe00 100644
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -1141,6 +1141,7 @@ BasicBlock *llvm::splitBlockBefore(BasicBlock *Old, BasicBlock::iterator SplitPt
 }
 
 /// Update DominatorTree, LoopInfo, and LCCSA analysis information.
+/// Invalidates DFS Numbering when DTU or DT is provided.
 static void UpdateAnalysisInformation(BasicBlock *OldBB, BasicBlock *NewBB,
                                       ArrayRef<BasicBlock *> Preds,
                                       DomTreeUpdater *DTU, DominatorTree *DT,