[clang] [Clang] Re-write codegen for atomic_test_and_set and atomic_clear (PR #121943)

[Oliver Stannard via cfe-commits]

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@@ -284,11 +284,26 @@ void f(_Atomic(int) *i, const _Atomic(int) *ci,
 
   const volatile int flag_k = 0;
   volatile int flag = 0;
-  (void)(int)__atomic_test_and_set(&flag_k, memory_order_seq_cst); // expected-warning {{passing 'const volatile int *' to parameter of type 'volatile void *'}}
+  (void)(int)__atomic_test_and_set(&flag_k, memory_order_seq_cst); // expected-error {{address argument to atomic operation must be a pointer to non-const type ('const volatile int *' invalid)}}
   (void)(int)__atomic_test_and_set(&flag, memory_order_seq_cst);
-  __atomic_clear(&flag_k, memory_order_seq_cst); // expected-warning {{passing 'const volatile int *' to parameter of type 'volatile void *'}}
+  __atomic_clear(&flag_k, memory_order_seq_cst); // expected-error {{address argument to atomic operation must be a pointer to non-const type ('const volatile int *' invalid)}}
   __atomic_clear(&flag, memory_order_seq_cst);
   (int)__atomic_clear(&flag, memory_order_seq_cst); // expected-error {{operand of type 'void'}}
+  __atomic_clear(0x8000, memory_order_seq_cst); // expected-error {{address argument to atomic builtin must be a pointer ('int' invalid)}}
+  __atomic_clear(&flag, memory_order_consume); // expected-warning {{memory order argument to atomic operation is invalid}}
+  __atomic_clear(&flag, memory_order_acquire); // expected-warning {{memory order argument to atomic operation is invalid}}
+  __atomic_clear(&flag, memory_order_acq_rel); // expected-warning {{memory order argument to atomic operation is invalid}}
+
+  // These intrinsics accept any non-const pointer type (including
+  // pointer-to-incomplete), and access the first byte.
+  __atomic_test_and_set((void*)0x8000, memory_order_seq_cst);
+  __atomic_test_and_set((char*)0x8000, memory_order_seq_cst);
+  __atomic_test_and_set((int*)0x8000, memory_order_seq_cst);
+  __atomic_test_and_set((struct incomplete*)0x8000, memory_order_seq_cst);
+  __atomic_clear((void*)0x8000, memory_order_seq_cst);
+  __atomic_clear((char*)0x8000, memory_order_seq_cst);
+  __atomic_clear((int*)0x8000, memory_order_seq_cst);
+  __atomic_clear((struct incomplete*)0x8000, memory_order_seq_cst);
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ostannard wrote:

Done

https://github.com/llvm/llvm-project/pull/121943