[clang] [HLSL] Add Append/ConsumeStructuredBuffer definitions to HLSLExternalSemaSource (PR #113643)

[Helena Kotas via cfe-commits]

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@@ -530,6 +530,28 @@ void HLSLExternalSemaSource::defineHLSLTypesWithForwardDeclarations() {
         .addArraySubscriptOperators()
         .completeDefinition();
   });
+
+  Decl =
+      BuiltinTypeDeclBuilder(*SemaPtr, HLSLNamespace, "AppendStructuredBuffer")
+          .addSimpleTemplateParams(*SemaPtr, {"element_type"})
+          .Record;
+  onCompletion(Decl, [this](CXXRecordDecl *Decl) {
+    setupBufferType(Decl, *SemaPtr, ResourceClass::UAV,
+                    ResourceKind::TypedBuffer, /*IsROV=*/false,
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hekota wrote:

The `ResourceKind` enumeration is passing into the `HLSLResource` attribute which si going away soon (llvm/llvm-project#104862). I agree it is confusing though. I'll change it here and in all of the other structured buffers.

https://github.com/llvm/llvm-project/pull/113643