[libc++abi] NFC: Move AtomicInt to cxa_guard_impl.h

[ldionne]

Summary

Since the atomic_support.h header of libc++abi is considered technical
debt (since we should use libc++'s), it's better not to add new
definitions to it, which makes it diverge from the original libc++
header even more.

[EricWF]

Is this just a clean move, or is the class definition changed as well?
I can't tell with all the linter warnings in the way.

If it's just a move, this LGTM.

[ldionne]

In D75950#1918278, @EricWF wrote:

Is this just a clean move, or is the class definition changed as well?
I can't tell with all the linter warnings in the way.

If it's just a move, this LGTM.

It's just a clean move!

libcxxabi/src/cxa_guard_impl.h

T& get() {
     }
     return value;
   }
  private:
   T value;
   bool is_init = false;
 };
 
+template <class IntType>
+class AtomicInt {
+public:
+  using MemoryOrder = std::__libcpp_atomic_order;
+
+  explicit AtomicInt(IntType *b) : b(b) {}
+  AtomicInt(AtomicInt const&) = delete;
+  AtomicInt& operator=(AtomicInt const&) = delete;
+
+  IntType load(MemoryOrder ord) {
+    return std::__libcpp_atomic_load(b, ord);
+  }
+  void store(IntType val, MemoryOrder ord) {
+    std::__libcpp_atomic_store(b, val, ord);
+  }
+  IntType exchange(IntType new_val, MemoryOrder ord) {
+    return std::__libcpp_atomic_exchange(b, new_val, ord);
+  }
+  bool compare_exchange(IntType *expected, IntType desired, MemoryOrder ord_success, MemoryOrder ord_failure) {
+    return std::__libcpp_atomic_compare_exchange(b, expected, desired, ord_success, ord_failure);
+  }
+
+private:
+  IntType *b;
+};
+
 //===----------------------------------------------------------------------===//
 //                       PlatformGetThreadID
 //===----------------------------------------------------------------------===//
 
 #if defined(__APPLE__) && defined(_LIBCPP_HAS_THREAD_API_PTHREAD)
 uint32_t PlatformThreadID() {
   static_assert(sizeof(mach_port_t) == sizeof(uint32_t), "");
   return static_cast<uint32_t>(

libcxxabi/src/include/atomic_support.h

 }
 
 #endif // _LIBCPP_HAS_NO_THREADS
 
 } // end namespace
 
 _LIBCPP_END_NAMESPACE_STD
 
-namespace {
-
-template <class IntType>
-class AtomicInt {
-public:
-  using MemoryOrder = std::__libcpp_atomic_order;
-
-  explicit AtomicInt(IntType *b) : b(b) {}
-  AtomicInt(AtomicInt const&) = delete;
-  AtomicInt& operator=(AtomicInt const&) = delete;
-
-  IntType load(MemoryOrder ord) {
-    return std::__libcpp_atomic_load(b, ord);
-  }
-  void store(IntType val, MemoryOrder ord) {
-    std::__libcpp_atomic_store(b, val, ord);
-  }
-  IntType exchange(IntType new_val, MemoryOrder ord) {
-    return std::__libcpp_atomic_exchange(b, new_val, ord);
-  }
-  bool compare_exchange(IntType *expected, IntType desired, MemoryOrder ord_success, MemoryOrder ord_failure) {
-    return std::__libcpp_atomic_compare_exchange(b, expected, desired, ord_success, ord_failure);
-  }
-
-private:
-  IntType *b;
-};
-
-} // end namespace
-
 #endif // ATOMIC_SUPPORT_H