[llvm] [SelectionDAG] Stop storing EVTs in a function scoped static std::set. (PR #118715)

[Matt Arsenault via llvm-commits]

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@@ -247,6 +248,9 @@ class SelectionDAG {
   BlockFrequencyInfo *BFI = nullptr;
   MachineModuleInfo *MMI = nullptr;
 
+  /// Extended EVTs used for single value VTLists.
+  std::set<EVT, EVT::compareRawBits> EVTs;
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arsenm wrote:

Did you try all the set types? Does DenseSet do any better? 

https://github.com/llvm/llvm-project/pull/118715