[llvm] [CGData] Outlined Hash Tree (PR #89792)

[Kyungwoo Lee via llvm-commits]

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@@ -105,6 +114,68 @@ void SuffixTree::setSuffixIndices() {
   }
 }
 
+void SuffixTree::setLeafNodes() {
+  // A stack that keeps track of nodes to visit for post-order DFS traversal.
+  std::stack<SuffixTreeNode *> ToVisit;
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kyulee-com wrote:

I think this comment goes to https://github.com/llvm/llvm-project/pull/90275. @xuanzh-meta 
But I believe it should be a stack semantic, so you can use `SmallVector` with `pop_back_val()` and `emplace_back()` like the above comment.

https://github.com/llvm/llvm-project/pull/89792