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diff --git a/src/memory.cpp b/src/memory.cpp
index 4b2a369..e318eee 100644
--- a/src/memory.cpp
+++ b/src/memory.cpp
@@ -21,7 +21,11 @@
# endif
#endif
+#if !defined(_LIBCPP_HAS_NO_THREADS)
+#include <atomic>
+#else
#include "include/atomic_support.h"
+#endif
_LIBCPP_BEGIN_NAMESPACE_STD
@@ -45,13 +49,21 @@ __shared_weak_count::~__shared_weak_count()
void
__shared_count::__add_shared() noexcept
{
+#ifdef _LIBCPP_HAS_NO_THREADS
__libcpp_atomic_refcount_increment(__shared_owners_);
+#else
+ ++__shared_owners_;
+#endif
}
bool
__shared_count::__release_shared() noexcept
{
+#ifdef _LIBCPP_HAS_NO_THREADS
if (__libcpp_atomic_refcount_decrement(__shared_owners_) == -1)
+#else
+ if (--__shared_owners_ == -1)
+#endif
{
__on_zero_shared();
return true;
@@ -68,7 +80,11 @@ __shared_weak_count::__add_shared() noexcept
void
__shared_weak_count::__add_weak() noexcept
{
+#ifdef _LIBCPP_HAS_NO_THREADS
__libcpp_atomic_refcount_increment(__shared_weak_owners_);
+#else
+ ++__shared_weak_owners_;
+#endif
}
void
@@ -103,26 +119,42 @@ __shared_weak_count::__release_weak() noexcept
// threads, and have them all get copied at once. The argument
// also doesn't apply for __release_shared, because an outstanding
// weak_ptr::lock() could read / modify the shared count.
+#ifdef _LIBCPP_HAS_NO_THREADS
if (__libcpp_atomic_load(&__shared_weak_owners_, _AO_Acquire) == 0)
+#else
+ if (__shared_weak_owners_.load(memory_order_acquire) == 0)
+#endif
{
// no need to do this store, because we are about
// to destroy everything.
//__libcpp_atomic_store(&__shared_weak_owners_, -1, _AO_Release);
__on_zero_shared_weak();
}
+#ifdef _LIBCPP_HAS_NO_THREADS
else if (__libcpp_atomic_refcount_decrement(__shared_weak_owners_) == -1)
+#else
+ else if (--__shared_weak_owners_ == -1)
+#endif
__on_zero_shared_weak();
}
__shared_weak_count*
__shared_weak_count::lock() noexcept
{
+#ifdef _LIBCPP_HAS_NO_THREADS
long object_owners = __libcpp_atomic_load(&__shared_owners_);
+#else
+ long object_owners = __shared_owners_.load();
+#endif
while (object_owners != -1)
{
+#ifdef _LIBCPP_HAS_NO_THREADS
if (__libcpp_atomic_compare_exchange(&__shared_owners_,
&object_owners,
object_owners+1))
+#else
+ if (__shared_owners_.compare_exchange_weak(object_owners, object_owners+1))
+#endif
return this;
}
return nullptr;
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