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

[Helena Kotas via cfe-commits]

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@@ -271,53 +246,70 @@ struct BuiltinTypeDeclBuilder {
     return *this;
   }
 
+  FieldDecl *getResourceHandleField() {
+    FieldDecl *FD = Fields["h"];
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hekota wrote:

Yeah, it would probably work fine too, if default value `ValueTy()` just means `nullptr` when `ValueTy` is a pointer.
I looked at the `lookup` documentation and it says: "Return the entry for the specified key, or a default constructed value if no such entry exists."

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