[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:

Both [] operator and lookup will add the field if it is not already there. I will update it to use "find".

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