[clang] [CIR] Upstream `AddressSpace` support for `PointerType` (PR #161028)

[Andy Kaylor via cfe-commits]

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@@ -226,32 +228,59 @@ def CIR_PointerType : CIR_Type<"Pointer", "ptr", [
 ]> {
   let summary = "CIR pointer type";
   let description = [{
-    The `!cir.ptr` type represents C and C++ pointer types and C++ reference
-    types, other than pointers-to-members.  The `pointee` type is the type
-    pointed to.
+    The `!cir.ptr` type is a typed pointer type. It is used to represent
+    pointers to objects in C/C++. The type of the pointed-to object is given by
+    the `pointee` parameter. The `addrSpace` parameter is an optional address
+    space attribute that specifies the address space of the pointer. If not
+    specified, the pointer is assumed to be in the default address space.
 
-    TODO(CIR): The address space attribute is not yet implemented.
+    The `!cir.ptr` type can point to any type, including fundamental types,
+    records, arrays, vectors, functions, and other pointers. It can also point
+    to incomplete types, such as incomplete records.
+
+    Note: Data-member pointers and method pointers are represented by
+    `!cir.data_member` and `!cir.method` types, respectively not by
+    `!cir.ptr` type.
----------------
andykaylor wrote:

This should probably be removed until support for those attributes is upstreamed.

https://github.com/llvm/llvm-project/pull/161028