[clang] [llvm] [HLSL] Add `Increment`/`DecrementCounter` methods to structured buffers (PR #114148)

[Helena Kotas via cfe-commits]

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@@ -343,27 +336,224 @@ struct TemplateParameterListBuilder {
     Params.clear();
 
     QualType T = Builder.Template->getInjectedClassNameSpecialization();
-    T = S.Context.getInjectedClassNameType(Builder.Record, T);
+    T = AST.getInjectedClassNameType(Builder.Record, T);
 
     return Builder;
   }
 };
+
+// Builder for methods of builtin types. Allows adding methods to builtin types
+// using the builder pattern like this:
+//
+//   BuiltinTypeMethodBuilder(Sema, RecordBuilder, "MethodName", ReturnType)
+//       .addParam("param_name", Type, InOutModifier)
+//       .callBuiltin("buildin_name", { BuiltinParams })
+//       .finalizeMethod();
+//
+// The builder needs to have all of the method parameters before it can create
+// a CXXMethodDecl. It collects them in addParam calls and when a first
+// method that builds the body is called it creates the CXXMethodDecl and
+// ParmVarDecls instances. These can then be referenced from the body building
+// methods. Destructor or an explicit call to finalizeMethod() will complete
+// the method definition.
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hekota wrote:

@tex3d - Justin is looking into having `callBuiltin` take placeholder values (something like `std::placeholders`) that would be used to reference the handle and method arguments.

@bogner FYI 

https://github.com/llvm/llvm-project/pull/114148