Import libcxxrt / libc++ into a vendor branch.

Approved by:	dim (mentor)

1 files changed, 168 insertions, 0 deletions

diff --git a/src/memory.cpp b/src/memory.cpp
new file mode 100644
index 0000000..cb5e5e7
--- /dev/null
+++ b/src/memory.cpp
@@ -0,0 +1,168 @@
+//===------------------------ memory.cpp ----------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "memory"
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace
+{
+
+template <class T>
+inline T
+increment(T& t) _NOEXCEPT
+{
+    return __sync_add_and_fetch(&t, 1);
+}
+
+template <class T>
+inline T
+decrement(T& t) _NOEXCEPT
+{
+    return __sync_add_and_fetch(&t, -1);
+}
+
+}  // namespace
+
+const allocator_arg_t allocator_arg = allocator_arg_t();
+
+bad_weak_ptr::~bad_weak_ptr() _NOEXCEPT {}
+
+const char*
+bad_weak_ptr::what() const _NOEXCEPT
+{
+    return "bad_weak_ptr";
+}
+
+__shared_count::~__shared_count()
+{
+}
+
+void
+__shared_count::__add_shared() _NOEXCEPT
+{
+    increment(__shared_owners_);
+}
+
+bool
+__shared_count::__release_shared() _NOEXCEPT
+{
+    if (decrement(__shared_owners_) == -1)
+    {
+        __on_zero_shared();
+        return true;
+    }
+    return false;
+}
+
+__shared_weak_count::~__shared_weak_count()
+{
+}
+
+void
+__shared_weak_count::__add_shared() _NOEXCEPT
+{
+    __shared_count::__add_shared();
+}
+
+void
+__shared_weak_count::__add_weak() _NOEXCEPT
+{
+    increment(__shared_weak_owners_);
+}
+
+void
+__shared_weak_count::__release_shared() _NOEXCEPT
+{
+    if (__shared_count::__release_shared())
+        __release_weak();
+}
+
+void
+__shared_weak_count::__release_weak() _NOEXCEPT
+{
+    if (decrement(__shared_weak_owners_) == -1)
+        __on_zero_shared_weak();
+}
+
+__shared_weak_count*
+__shared_weak_count::lock() _NOEXCEPT
+{
+    long object_owners = __shared_owners_;
+    while (object_owners != -1)
+    {
+        if (__sync_bool_compare_and_swap(&__shared_owners_,
+                                         object_owners,
+                                         object_owners+1))
+        {
+            __add_weak();
+            return this;
+        }
+        object_owners = __shared_owners_;
+    }
+    return 0;
+}
+
+#ifndef _LIBCPP_NO_RTTI
+
+const void*
+__shared_weak_count::__get_deleter(const type_info&) const _NOEXCEPT
+{
+    return 0;
+}
+
+#endif  // _LIBCPP_NO_RTTI
+
+void
+declare_reachable(void*)
+{
+}
+
+void
+declare_no_pointers(char*, size_t)
+{
+}
+
+void
+undeclare_no_pointers(char*, size_t)
+{
+}
+
+pointer_safety
+get_pointer_safety() _NOEXCEPT
+{
+    return pointer_safety::relaxed;
+}
+
+void*
+__undeclare_reachable(void* p)
+{
+    return p;
+}
+
+void*
+align(size_t alignment, size_t size, void*& ptr, size_t& space)
+{
+    void* r = nullptr;
+    if (size <= space)
+    {
+        char* p1 = static_cast<char*>(ptr);
+        char* p2 = (char*)((size_t)(p1 + (alignment - 1)) & -alignment);
+        ptrdiff_t d = p2 - p1;
+        if (d <= space - size)
+        {
+            r = p2;
+            ptr = r;
+            space -= d;
+        }
+    }
+    return r;
+}
+
+_LIBCPP_END_NAMESPACE_STD