[clang] [clang][PAC] add support for options parameter to __ptrauth (PR #136828)

[Oliver Hunt via cfe-commits]

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@@ -3595,9 +3595,9 @@ def ObjCRequiresPropertyDefs : InheritableAttr {
 
 def PointerAuth : TypeAttr {
   let Spellings = [CustomKeyword<"__ptrauth">];
-  let Args = [IntArgument<"Key">,
-              BoolArgument<"AddressDiscriminated", 1>,
-              IntArgument<"ExtraDiscriminator", 1>];
+  let Args = [IntArgument<"Key">, BoolArgument<"AddressDiscriminated", 1>,
+              IntArgument<"ExtraDiscriminator", 1>,
+              StringArgument<"Options", 1>];
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ojhunt wrote:

I'll see if there's any existing documentation as the attribute can't be specified by attribute syntax

https://github.com/llvm/llvm-project/pull/136828