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

[David Rivera via cfe-commits]

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@@ -35,4 +35,28 @@ class CIR_DefaultValuedEnumParameter<EnumAttrInfo info, string value = "">
   let defaultValue = value;
 }
 
+def CIR_AddressSpace : CIR_I32EnumAttr<
+  "AddressSpace", "address space kind", [
+  I32EnumAttrCase<"Default", 0, "default">,
+  I32EnumAttrCase<"OffloadPrivate", 1, "offload_private">,
+  I32EnumAttrCase<"OffloadLocal", 2, "offload_local">,
+  I32EnumAttrCase<"OffloadGlobal", 3, "offload_global">,
+  I32EnumAttrCase<"OffloadConstant", 4, "offload_constant">,
+  I32EnumAttrCase<"OffloadGeneric", 5, "offload_generic">,
+  I32EnumAttrCase<"Target", 6, "target">
+]> {
+  let description = [{
+    The `address_space` attribute is used to represent address spaces for
+    pointer types in CIR. It provides a unified model on top of `clang::LangAS`
+    and simplifies the representation of address spaces.
+
+    The `value` parameter is an extensible enum, which encodes target address
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RiverDave wrote:

Fixed.

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