[llvm] [BranchFolding] Add a hook to tail merge only bbs without successors (PR #101969)

[Vladimir Radosavljevic via llvm-commits]

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@@ -1035,6 +1040,9 @@ bool BranchFolder::TailMergeBlocks(MachineFunction &MF) {
   if (MergePotentials.size() >= 2)
     MadeChange |= TryTailMergeBlocks(nullptr, nullptr, MinCommonTailLength);
 
+  if (TailMergeOnlyBBsWithoutSucc)
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vladimirradosavljevic wrote:

I went with a 2nd approach to create target hook, so we can use it in a downstream target. PTAL.

https://github.com/llvm/llvm-project/pull/101969