[clang] [clang] Optimize castToDeclContext for 2% improvement in build times (PR #76825)

[Vlad Serebrennikov via cfe-commits]

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@@ -95,8 +103,31 @@ std::pair<ASTNode, ASTNode> ClangASTNodesEmitter::EmitNode(raw_ostream &OS,
   if (!Base.isAbstract())
     First = Last = Base;
 
+  class Comp {
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Endilll wrote:

This class looks like a hand-written lambda closure type. Do we really need it in this form?

https://github.com/llvm/llvm-project/pull/76825