[clang] [clang][ptrauth] Add support for querying the ptrauth schema of a type (PR #138482)

[Oliver Hunt via cfe-commits]

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@@ -605,6 +605,11 @@ KEYWORD(__private_extern__          , KEYALL)
 KEYWORD(__module_private__          , KEYALL)
 
 UNARY_EXPR_OR_TYPE_TRAIT(__builtin_ptrauth_type_discriminator, PtrAuthTypeDiscriminator, KEYALL)
+UNARY_EXPR_OR_TYPE_TRAIT(__builtin_ptrauth_has_authentication, PtrAuthHasAuthentication, KEYALL)
+UNARY_EXPR_OR_TYPE_TRAIT(__builtin_ptrauth_schema_key, PtrAuthSchemaKey, KEYALL)
+UNARY_EXPR_OR_TYPE_TRAIT(__builtin_ptrauth_schema_is_address_discriminated, PtrAuthSchemaIsAddressDiscriminated, KEYALL)
+UNARY_EXPR_OR_TYPE_TRAIT(__builtin_ptrauth_schema_extra_discriminator, PtrAuthSchemaExtraDiscriminator, KEYALL)
+UNARY_EXPR_OR_TYPE_TRAIT(__builtin_ptrauth_schema_options, PtrAuthSchemaOptions, KEYALL)
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ojhunt wrote:

do we have a type trait macro? (I actually thought that they did support expressions, but I realize that all the code I've written using them always uses decltype anyway, and it's not as if there's existing code that could break - probably)

https://github.com/llvm/llvm-project/pull/138482