[clang-tools-extra] [clang] [Attributes][HLSL] Teach EnumArgument to refer to an external enum (PR #70835)

[Erich Keane via cfe-commits]

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@@ -277,23 +277,28 @@ class DefaultIntArgument<string name, int default> : IntArgument<name, 1> {
   int Default = default;
 }
 
-// This argument is more complex, it includes the enumerator type name,
-// a list of strings to accept, and a list of enumerators to map them to.
+// This argument is more complex, it includes the enumerator type
+// name, whether the enum type is externally defined, a list of
+// strings to accept, and a list of enumerators to map them to.
 class EnumArgument<string name, string type, list<string> values,
-                   list<string> enums, bit opt = 0, bit fake = 0>
+                   list<string> enums, bit opt = 0, bit fake = 0,
+                   bit external = 0>
     : Argument<name, opt, fake> {
   string Type = type;
   list<string> Values = values;
   list<string> Enums = enums;
+  bit External = external;
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erichkeane wrote:

I could have sworn you changed this at one point... Something like `IsExternalType` is significantly more self-documenting here.

https://github.com/llvm/llvm-project/pull/70835