[clang] [CIR] Upstream minimal support for structure types (PR #135105)

[Erich Keane via cfe-commits]

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@@ -400,13 +400,126 @@ def VoidPtr : Type<
       "cir::VoidType::get($_builder.getContext()))"> {
 }
 
+//===----------------------------------------------------------------------===//
+// StructType
+//
+// The base type for all RecordDecls.
+//===----------------------------------------------------------------------===//
+
+def CIR_StructType : CIR_Type<"Struct", "struct",
+    [
+      DeclareTypeInterfaceMethods<DataLayoutTypeInterface>,
+      MutableType,
+    ]> {
+  let summary = "CIR struct type";
+  let description = [{
+    Each unique clang::RecordDecl is mapped to a `cir.struct` and any object in
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erichkeane wrote:

Definitely in favor of the rename, and fixes most of my concerns on this patch TBH.

https://github.com/llvm/llvm-project/pull/135105