[clang] [PAC] Add support for __ptrauth type qualifier (PR #100830)

[Daniil Kovalev via cfe-commits]

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@@ -0,0 +1,84 @@
+// RUN: %clang_cc1 -triple arm64-apple-ios -fsyntax-only -verify -fptrauth-intrinsics %s
+
+#include <ptrauth.h>
+
+#if __has_feature(ptrauth_qualifier)
+#warning __ptrauth qualifier enabled!
+// expected-warning at -1 {{__ptrauth qualifier enabled!}}
+#endif
+
+#if __aarch64__
+#define VALID_CODE_KEY 0
+#define VALID_DATA_KEY 2
+#define INVALID_KEY 200
+#else
+#error Provide these constants if you port this test
+#endif
+
+int * __ptrauth(VALID_DATA_KEY) valid0;
+
+typedef int *intp;
+
+int nonConstantGlobal = 5;
+
+__ptrauth int invalid0; // expected-error{{expected '('}}
+__ptrauth() int invalid1; // expected-error{{expected expression}}
+__ptrauth(INVALID_KEY) int invalid2; // expected-error{{200 does not identify a valid pointer authentication key for the current target}}
+__ptrauth(VALID_DATA_KEY) int invalid3; // expected-error{{__ptrauth qualifier may only be applied to pointer types}}
+__ptrauth(VALID_DATA_KEY) int *invalid4; // expected-error{{__ptrauth qualifier may only be applied to pointer types}}
+int * (__ptrauth(VALID_DATA_KEY) invalid5); // expected-error{{expected identifier or '('}} expected-error{{expected ')'}} expected-note {{to match this '('}}
+int *__ptrauth(VALID_DATA_KEY) __ptrauth(VALID_DATA_KEY) invalid6; // expected-error{{type 'int *__ptrauth(2,0,0)' is already __ptrauth-qualified}}
+int * __ptrauth(VALID_DATA_KEY, 2) invalid7; // expected-error{{address discrimination flag for __ptrauth must be 0 or 1; value is 2}}
+int * __ptrauth(VALID_DATA_KEY, -1) invalid8; // expected-error{{address discrimination flag for __ptrauth must be 0 or 1; value is -1}}
+int * __ptrauth(VALID_DATA_KEY, 1, -1) invalid9; // expected-error{{extra discriminator for __ptrauth must be between 0 and 65535; value is -1}}
+int * __ptrauth(VALID_DATA_KEY, 1, 100000) invalid10; // expected-error{{extra discriminator for __ptrauth must be between 0 and 65535; value is 100000}}
+int * __ptrauth(VALID_DATA_KEY, 1, nonConstantGlobal) invalid12; // expected-error{{argument to __ptrauth must be an integer constant expression}}
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kovdan01 wrote:

Can we also test non-constant-expression for key and address discrimination fields?

https://github.com/llvm/llvm-project/pull/100830