[libc++] Replace __sync_* functions with __libcpp_atomic_* functions
Summary:
This patch replaces __sync_* with __libcpp_atomic_* and adds a wrapper
function for __atomic_exchange to support _LIBCPP_HAS_NO_THREADS.
Reviewers: EricWF, jroelofs, mclow.lists, compnerd
Reviewed By: EricWF, compnerd
Subscribers: compnerd, efriedma, cfe-commits, joerg, llvm-commits
Differential Revision: https://reviews.llvm.org/D35235
llvm-svn: 313694
diff --git a/libcxx/src/include/atomic_support.h b/libcxx/src/include/atomic_support.h
index 08847e6..ccd8d78 100644
--- a/libcxx/src/include/atomic_support.h
+++ b/libcxx/src/include/atomic_support.h
@@ -16,6 +16,7 @@
#if defined(__clang__) && __has_builtin(__atomic_load_n) \
&& __has_builtin(__atomic_store_n) \
&& __has_builtin(__atomic_add_fetch) \
+ && __has_builtin(__atomic_exchange_n) \
&& __has_builtin(__atomic_compare_exchange_n) \
&& defined(__ATOMIC_RELAXED) \
&& defined(__ATOMIC_CONSUME) \
@@ -84,6 +85,14 @@
template <class _ValueType>
inline _LIBCPP_INLINE_VISIBILITY
+_ValueType __libcpp_atomic_exchange(_ValueType* __target,
+ _ValueType __value, int __order = _AO_Seq)
+{
+ return __atomic_exchange_n(__target, __value, __order);
+}
+
+template <class _ValueType>
+inline _LIBCPP_INLINE_VISIBILITY
bool __libcpp_atomic_compare_exchange(_ValueType* __val,
_ValueType* __expected, _ValueType __after,
int __success_order = _AO_Seq,
@@ -137,6 +146,16 @@
template <class _ValueType>
inline _LIBCPP_INLINE_VISIBILITY
+_ValueType __libcpp_atomic_exchange(_ValueType* __target,
+ _ValueType __value, int __order = _AO_Seq)
+{
+ _ValueType old = *__target;
+ *__target = __value;
+ return old;
+}
+
+template <class _ValueType>
+inline _LIBCPP_INLINE_VISIBILITY
bool __libcpp_atomic_compare_exchange(_ValueType* __val,
_ValueType* __expected, _ValueType __after,
int = 0, int = 0)