[clang] [clang] Add arm64e ABI-defined key assignments to ptrauth.h. (PR #93901)

[Ahmed Bougacha via cfe-commits]

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@@ -15,6 +15,29 @@ typedef enum {
   ptrauth_key_asib = 1,
   ptrauth_key_asda = 2,
   ptrauth_key_asdb = 3,
+
+#ifdef __APPLE__
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ahmedbougacha wrote:

Great, let's do that;  I also removed the comments that talk about enablement policy, that seems like a separate problem if this is to be generic

https://github.com/llvm/llvm-project/pull/93901