[clang] Add limited vtable address querying to `clang::CodeGenerator` (PR #202807)

[Richard Smith via cfe-commits]

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@@ -105,6 +106,8 @@ class CodeGenerator : public ASTConsumer {
   ///   definition has been registered with this code generator.
   llvm::Constant *GetAddrOfGlobal(GlobalDecl decl, bool isForDefinition);
 
+  llvm::Constant *GetAddrOfVTable(BaseSubobject base, CXXRecordDecl *decl);
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zygoloid wrote:

This function should have a documentation comment. Can we make the `decl` parameter `const`?

https://github.com/llvm/llvm-project/pull/202807