[clang] [HLSL] Collect explicit resource binding information (PR #111203)

[Helena Kotas via cfe-commits]

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@@ -985,44 +983,43 @@ SemaHLSL::TakeLocForHLSLAttribute(const HLSLAttributedResourceType *RT) {
   return LocInfo;
 }
 
-// get the record decl from a var decl that we expect
-// represents a resource
-static CXXRecordDecl *getRecordDeclFromVarDecl(VarDecl *VD) {
-  const Type *Ty = VD->getType()->getPointeeOrArrayElementType();
-  assert(Ty && "Resource must have an element type.");
-
-  if (Ty->isBuiltinType())
-    return nullptr;
-
-  CXXRecordDecl *TheRecordDecl = Ty->getAsCXXRecordDecl();
-  assert(TheRecordDecl && "Resource should have a resource type declaration.");
-  return TheRecordDecl;
-}
-
+// Returns handle type of a resource, if the VarDecl is a resource
+// or an array of resources
 static const HLSLAttributedResourceType *
-findAttributedResourceTypeOnField(VarDecl *VD) {
+FindHandleTypeOnResource(const VarDecl *VD) {
+  // If VarDecl is a resource class, the first field must
+  // be the resource handle of type HLSLAttributedResourceType
   assert(VD != nullptr && "expected VarDecl");
-  if (RecordDecl *RD = getRecordDeclFromVarDecl(VD)) {
-    for (auto *FD : RD->fields()) {
-      if (const HLSLAttributedResourceType *AttrResType =
-              dyn_cast<HLSLAttributedResourceType>(FD->getType().getTypePtr()))
-        return AttrResType;
+  const Type *Ty = VD->getType()->getPointeeOrArrayElementType();
+  if (RecordDecl *RD = Ty->getAsCXXRecordDecl()) {
+    if (!RD->fields().empty()) {
+      const auto &FirstFD = RD->fields().begin();
+      return dyn_cast<HLSLAttributedResourceType>(
+          FirstFD->getType().getTypePtr());
     }
   }
   return nullptr;
 }
 
-// Iterate over RecordType fields and return true if any of them matched the
-// register type
-static bool ContainsResourceForRegisterType(Sema &S, const RecordType *RT,
-                                            RegisterType RegType) {
+// Walks though the user defined record type, finds resource class
+// that matches the RegisterBinding.Type and assigns it to
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hekota wrote:

Outdated.

https://github.com/llvm/llvm-project/pull/111203