[clang] [PAC] Define __builtin_ptrauth_type_discriminator (PR #100204)

[Daniil Kovalev via cfe-commits]

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@@ -0,0 +1,64 @@
+// RUN: %clang_cc1 -triple arm64-apple-ios -std=c++17 -Wno-vla -fsyntax-only -verify -fptrauth-intrinsics %s
+// RUN: %clang_cc1 -triple aarch64-linux-gnu -std=c++17 -Wno-vla -fsyntax-only -verify -fptrauth-intrinsics %s
+
+// RUN: not %clang_cc1 -triple arm64-apple-ios -std=c++17 -Wno-vla -fsyntax-only %s 2>&1 | FileCheck %s
+// CHECK: this target does not support pointer authentication
+
+struct S {
+  virtual int foo();
+};
+
+template <class T>
+constexpr unsigned dependentOperandDisc() {
+  return __builtin_ptrauth_type_discriminator(T);
+}
+
+void test_builtin_ptrauth_type_discriminator(unsigned s) {
+  typedef int (S::*MemFnTy)();
+  MemFnTy memFnPtr;
+  int (S::*memFnPtr2)();
+  constexpr unsigned d0 = __builtin_ptrauth_type_discriminator(MemFnTy);
+  static_assert(d0 == __builtin_ptrauth_string_discriminator("_ZTSM1SFivE"));
+  static_assert(d0 == 60844);
+  static_assert(__builtin_ptrauth_type_discriminator(int (S::*)()) == d0);
+  static_assert(__builtin_ptrauth_type_discriminator(decltype(memFnPtr)) == d0);
+  static_assert(__builtin_ptrauth_type_discriminator(decltype(memFnPtr2)) == d0);
+  static_assert(__builtin_ptrauth_type_discriminator(decltype(&S::foo)) == d0);
+  static_assert(dependentOperandDisc<decltype(&S::foo)>() == d0);
+
+  constexpr unsigned d1 = __builtin_ptrauth_type_discriminator(void (S::*)(int));
+  static_assert(__builtin_ptrauth_string_discriminator("_ZTSM1SFviE") == d1);
+  static_assert(d1 == 39121);
+
+  constexpr unsigned d2 = __builtin_ptrauth_type_discriminator(void (S::*)(float));
+  static_assert(__builtin_ptrauth_string_discriminator("_ZTSM1SFvfE") == d2);
+  static_assert(d2 == 52453);
+
+  constexpr unsigned d3 = __builtin_ptrauth_type_discriminator(int (*())[s]);
+  static_assert(__builtin_ptrauth_string_discriminator("FPE") == d3);
+  static_assert(d3 == 34128);
+
+  int f4(float);
+  constexpr unsigned d4 = __builtin_ptrauth_type_discriminator(decltype(f4));
+  static_assert(__builtin_ptrauth_type_discriminator(int (*)(float)) == d4);
+  static_assert(__builtin_ptrauth_string_discriminator("FifE") == d4);
+  static_assert(d4 == 48468);
+
+  int f5(int);
+  constexpr unsigned d5 = __builtin_ptrauth_type_discriminator(decltype(f5));
+  static_assert(__builtin_ptrauth_type_discriminator(int (*)(int)) == d5);
+  static_assert(__builtin_ptrauth_type_discriminator(short (*)(short)) == d5);
+  static_assert(__builtin_ptrauth_type_discriminator(char (*)(char)) == d5);
+  static_assert(__builtin_ptrauth_type_discriminator(long (*)(long)) == d5);
+  static_assert(__builtin_ptrauth_type_discriminator(unsigned int (*)(unsigned int)) == d5);
+  static_assert(__builtin_ptrauth_type_discriminator(int (&)(int)) == d5);
+  static_assert(__builtin_ptrauth_string_discriminator("FiiE") == d5);
+  static_assert(d5 == 2981);
+
+  int t;
+  int vmarray[s];
+  (void)__builtin_ptrauth_type_discriminator(t); // expected-error {{unknown type name 't'}}
+  (void)__builtin_ptrauth_type_discriminator(&t); // expected-error {{expected a type}}
+  (void)__builtin_ptrauth_type_discriminator(decltype(vmarray)); // expected-error {{cannot pass undiscriminated type 'decltype(vmarray)' (aka 'int[s]')}}
+  (void)__builtin_ptrauth_type_discriminator(int *); // expected-error {{cannot pass undiscriminated type 'int *' to '__builtin_ptrauth_type_discriminator'}}
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kovdan01 wrote:

Nit: it's probably worth adding tests when 0 or >=2 arguments are passed while 1 is expected.

https://github.com/llvm/llvm-project/pull/100204