[llvm] [CodeLayout][NFC] Using MergedVector to avoid extra vector allocations (PR #68724)

[Rahman Lavaee via llvm-commits]

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@@ -516,34 +518,54 @@ struct MergedChain {
   NodeIter End3;
 };
 
+/// A wrapper around two concatenated vectors (chains) of jumps.
+struct MergedJumpsT {
+  MergedJumpsT(const std::vector<JumpT *> *Jumps1,
+               const std::vector<JumpT *> *Jumps2 = nullptr) {
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rlavaee wrote:

This default value is unused.

https://github.com/llvm/llvm-project/pull/68724