[llvm] Replace copy with a reference. (PR #82485)

[Phoebe Wang via llvm-commits]

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@@ -712,7 +712,7 @@ void SelectOptimizeImpl::convertProfitableSIGroups(SelectGroups &ProfSIGroups) {
                                    SI.getCondition()->getName() + ".frozen");
 
     SmallPtrSet<const Instruction *, 2> INS;
-    for (auto SI : ASI)
+    for (auto &SI : ASI)
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phoebewang wrote:

The `SelectLike` is a small class. No need to use reference.

https://github.com/llvm/llvm-project/pull/82485