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

[Aaron Ballman via cfe-commits]

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@@ -0,0 +1,86 @@
+// RUN: %clang_cc1 -triple arm64-apple-ios -fsyntax-only -verify -fptrauth-intrinsics %s
+// RUN: %clang_cc1 -triple aarch64-linux-gnu -fsyntax-only -verify -fptrauth-intrinsics %s
+
+#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 only applies to pointer types; 'int' is invalid}}
+__ptrauth(VALID_DATA_KEY) int *invalid4; // expected-error {{'__ptrauth' qualifier only applies to pointer types; 'int' is invalid}}
+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 {{invalid address discrimination flag '2'; '__ptrauth' requires '0' or '1'}}
+int * __ptrauth(VALID_DATA_KEY, -1) invalid8; // expected-error {{invalid address discrimination flag '-1'; '__ptrauth' requires '0' or '1'}}
+int * __ptrauth(VALID_DATA_KEY, 1, -1) invalid9; // expected-error {{invalid extra discriminator flag '-1'; '__ptrauth' requires a value between '0' and '65535'}}
+int * __ptrauth(VALID_DATA_KEY, 1, 100000) invalid10; // expected-error {{invalid extra discriminator flag '100000'; '__ptrauth' requires a value between '0' and '65535'}}
+int * __ptrauth(VALID_DATA_KEY, 1, nonConstantGlobal) invalid12; // expected-error {{argument to '__ptrauth' must be an integer constant expression}}
+int * __ptrauth(VALID_DATA_KEY, nonConstantGlobal, 1000) invalid13; // expected-error {{argument to '__ptrauth' must be an integer constant expression}}
+int * __ptrauth(nonConstantGlobal, 1, 1000) invalid14; // expected-error{{expression is not an integer constant expression}}
+int * __ptrauth(VALID_DATA_KEY, 1, 1000, 12) invalid15; // expected-error{{qualifier must take between 1 and 3 arguments}}
+
+int * __ptrauth(VALID_DATA_KEY) valid0;
+int * __ptrauth(VALID_DATA_KEY) *valid1;
+__ptrauth(VALID_DATA_KEY) intp valid2;
+__ptrauth(VALID_DATA_KEY) intp *valid3;
+intp __ptrauth(VALID_DATA_KEY) valid4;
+intp __ptrauth(VALID_DATA_KEY) *valid5;
+int * __ptrauth(VALID_DATA_KEY, 0) valid6;
+int * __ptrauth(VALID_DATA_KEY, 1) valid7;
+int * __ptrauth(VALID_DATA_KEY, (_Bool) 1) valid8;
+int * __ptrauth(VALID_DATA_KEY, 1, 0) valid9;
+int * __ptrauth(VALID_DATA_KEY, 1, 65535) valid10;
+
+extern intp redeclaration0; // expected-note {{previous declaration}}
+extern intp __ptrauth(VALID_DATA_KEY) redeclaration0; // expected-error{{redeclaration of 'redeclaration0' with a different type: '__ptrauth(2,0,0) intp' (aka 'int *__ptrauth(2,0,0)') vs 'intp' (aka 'int *')}}
+
+extern intp redeclaration1; // expected-note {{previous declaration}}
+extern intp __ptrauth(VALID_DATA_KEY) redeclaration1; // expected-error{{redeclaration of 'redeclaration1' with a different type: '__ptrauth(2,0,0) intp' (aka 'int *__ptrauth(2,0,0)') vs 'intp' (aka 'int *')}}
+
+intp __ptrauth(VALID_DATA_KEY) redeclaration2; // expected-note {{previous definition}}
+intp redeclaration2 = 0;                       // expected-error{{redefinition of 'redeclaration2' with a different type: 'intp' (aka 'int *') vs '__ptrauth(2,0,0) intp' (aka 'int *__ptrauth(2,0,0)')}}
+
+intp __ptrauth(VALID_DATA_KEY) redeclaration3; // expected-note {{previous definition}}
+intp redeclaration3 = 0;                       // expected-error{{redefinition of 'redeclaration3' with a different type: 'intp' (aka 'int *') vs '__ptrauth(2,0,0) intp' (aka 'int *__ptrauth(2,0,0)')}}
+
+void illegal0(intp __ptrauth(VALID_DATA_KEY)); // expected-error {{parameter type may not be qualified with '__ptrauth'; type is '__ptrauth(2,0,0) intp' (aka 'int *__ptrauth(2,0,0)')}}
+intp __ptrauth(VALID_DATA_KEY) illegal1(void); // expected-error {{return type may not be qualified with '__ptrauth'; type is '__ptrauth(2,0,0) intp' (aka 'int *__ptrauth(2,0,0)')}}
+
+void test_code(intp p) {
+  p = (intp __ptrauth(VALID_DATA_KEY)) 0; // expected-error {{cannot cast to '__ptrauth'-qualified type '__ptrauth(2,0,0) intp' (aka 'int *__ptrauth(2,0,0)')}}
+
+  __ptrauth(VALID_DATA_KEY) intp pSpecial = p;
+  pSpecial = p;
+  intp pNormal = pSpecial;
+  pNormal = pSpecial;
+
+  intp __ptrauth(VALID_DATA_KEY) *ppSpecial0 = &pSpecial;
+  intp __ptrauth(VALID_DATA_KEY) *ppSpecial1 = &pNormal; // expected-error {{initializing '__ptrauth(2,0,0) intp *' (aka 'int *__ptrauth(2,0,0) *') with an expression of type 'intp *' (aka 'int **') changes pointer authentication of pointee type}}
+  intp *ppNormal0 = &pSpecial; // expected-error {{initializing 'intp *' (aka 'int **') with an expression of type '__ptrauth(2,0,0) intp *' (aka 'int *__ptrauth(2,0,0) *') changes pointer authentication of pointee type}}
+  intp *ppNormal1 = &pNormal;
+
+  intp *pp5 = (p ? &pSpecial : &pNormal); // expected-error {{'__ptrauth' qualification mismatch ('__ptrauth(2,0,0) intp *' (aka 'int *__ptrauth(2,0,0) *') and 'intp *' (aka 'int **'))}}
+}
+
+void test_array(void) {
----------------
AaronBallman wrote:

Should also test whether `_Generic` properly sees the qualifier, that `typeof` keeps the qualifier while `typeof_unqual` strips it, that `__attribute__((overloadable))` works with it, that it works properly on arrays (including VLAs).

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