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-rw-r--r--contrib/libc++/src/memory.cpp215
1 files changed, 215 insertions, 0 deletions
diff --git a/contrib/libc++/src/memory.cpp b/contrib/libc++/src/memory.cpp
new file mode 100644
index 0000000..3884a2b
--- /dev/null
+++ b/contrib/libc++/src/memory.cpp
@@ -0,0 +1,215 @@
+//===------------------------ 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.
+//
+//===----------------------------------------------------------------------===//
+
+#define _LIBCPP_BUILDING_MEMORY
+#include "memory"
+#include "mutex"
+#include "thread"
+
+_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))
+ 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
+
+#if __has_feature(cxx_atomic)
+
+static const std::size_t __sp_mut_count = 16;
+static mutex mut_back[__sp_mut_count];
+
+_LIBCPP_CONSTEXPR __sp_mut::__sp_mut(void* p) _NOEXCEPT
+ : _(p)
+{
+}
+
+void
+__sp_mut::lock() _NOEXCEPT
+{
+ mutex& m = *static_cast<mutex*>(_);
+ unsigned count = 0;
+ while (!m.try_lock())
+ {
+ if (++count > 16)
+ {
+ m.lock();
+ break;
+ }
+ this_thread::yield();
+ }
+}
+
+void
+__sp_mut::unlock() _NOEXCEPT
+{
+ static_cast<mutex*>(_)->unlock();
+}
+
+__sp_mut&
+__get_sp_mut(const void* p)
+{
+ static __sp_mut muts[__sp_mut_count]
+ {
+ &mut_back[ 0], &mut_back[ 1], &mut_back[ 2], &mut_back[ 3],
+ &mut_back[ 4], &mut_back[ 5], &mut_back[ 6], &mut_back[ 7],
+ &mut_back[ 8], &mut_back[ 9], &mut_back[10], &mut_back[11],
+ &mut_back[12], &mut_back[13], &mut_back[14], &mut_back[15]
+ };
+ return muts[hash<const void*>()(p) & (__sp_mut_count-1)];
+}
+
+#endif // __has_feature(cxx_atomic)
+
+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);
+ size_t d = static_cast<size_t>(p2 - p1);
+ if (d <= space - size)
+ {
+ r = p2;
+ ptr = r;
+ space -= d;
+ }
+ }
+ return r;
+}
+
+_LIBCPP_END_NAMESPACE_STD
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