[clang] Attach resource attributes to handle within record, instead of record (PR #101433)

[Justin Bogner via cfe-commits]

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@@ -280,18 +280,22 @@ void CGHLSLRuntime::annotateHLSLResource(const VarDecl *D, GlobalVariable *GV) {
   const auto *RD = Ty->getAsCXXRecordDecl();
   if (!RD)
     return;
-  const auto *HLSLResAttr = RD->getAttr<HLSLResourceAttr>();
-  const auto *HLSLResClassAttr = RD->getAttr<HLSLResourceClassAttr>();
-  if (!HLSLResAttr || !HLSLResClassAttr)
-    return;
+  // the resource related attributes are on the handle member
+  // inside the record decl
+  for (auto *FD : RD->fields()) {
+    const auto *HLSLResAttr = FD->getAttr<HLSLResourceAttr>();
+    const auto *HLSLResClassAttr = FD->getAttr<HLSLResourceClassAttr>();
+    if (!HLSLResAttr || !HLSLResClassAttr)
+      continue;
 
-  llvm::hlsl::ResourceClass RC = HLSLResClassAttr->getResourceClass();
-  llvm::hlsl::ResourceKind RK = HLSLResAttr->getResourceKind();
-  bool IsROV = HLSLResAttr->getIsROV();
-  llvm::hlsl::ElementType ET = calculateElementType(CGM.getContext(), Ty);
+    llvm::hlsl::ResourceClass RC = HLSLResClassAttr->getResourceClass();
+    llvm::hlsl::ResourceKind RK = HLSLResAttr->getResourceKind();
+    bool IsROV = HLSLResAttr->getIsROV();
+    llvm::hlsl::ElementType ET = calculateElementType(CGM.getContext(), Ty);
 
-  BufferResBinding Binding(D->getAttr<HLSLResourceBindingAttr>());
-  addBufferResourceAnnotation(GV, RC, RK, IsROV, ET, Binding);
+    BufferResBinding Binding(D->getAttr<HLSLResourceBindingAttr>());
+    addBufferResourceAnnotation(GV, RC, RK, IsROV, ET, Binding);
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bogner wrote:

Given that we're moving to the handle itself really being the resource, I think that if there were multiple fields with the attributes then that really is multiple bindings and the way this is done probably works ok. In any case, this code is going to go away when we implement #95952 anyways, since at that point the information we're currently keeping in `hlsl.uavs`/`hlsl.cbufs` will be carried to the backend by the handle itself rather than in metadata.

https://github.com/llvm/llvm-project/pull/101433