[clang] [Clang] Improve concept performance 1/N (PR #188421)

[Corentin Jabot via cfe-commits]

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@@ -15101,6 +15091,9 @@ class Sema final : public SemaBase {
                  UnsubstitutedConstraintSatisfactionCacheResult>
       UnsubstitutedConstraintSatisfactionCache;
 
+  llvm::DenseMap<llvm::FoldingSetNodeID, TemplateArgumentLoc>
+      *CurrentCachedTemplateArgs = nullptr;
+
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cor3ntin wrote:

Can you add a comment?

https://github.com/llvm/llvm-project/pull/188421