N3659: Shared locking in C++ Revision 2, c++1y only

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@191127 91177308-0d34-0410-b5e6-96231b3b80d8

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/copy_assign.fail.cpp

@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// shared_lock& operator=(shared_lock const&) = delete;
+
+#include <shared_mutex>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m0;
+std::shared_mutex m1;
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<std::shared_mutex> lk0(m0);
+    std::shared_lock<std::shared_mutex> lk1(m1);
+    lk1 = lk0;
+#else
+#   error
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/copy_ctor.fail.cpp

@@ -0,0 +1,30 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// shared_lock(shared_lock const&) = delete;
+
+#include <shared_mutex>
+
+#if _LIBCPP_STD_VER > 11
+std::shared_mutex m;
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<std::shared_mutex> lk0(m);
+    std::shared_lock<std::shared_mutex> lk = lk0;
+#else
+#   error
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/default.pass.cpp

@@ -0,0 +1,26 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// shared_lock();
+
+#include <shared_mutex>
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<std::shared_mutex> ul;
+    assert(!ul.owns_lock());
+    assert(ul.mutex() == nullptr);
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/move_assign.pass.cpp

@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// shared_lock& operator=(shared_lock&& u);
+
+#include <shared_mutex>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m0;
+std::shared_mutex m1;
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<std::shared_mutex> lk0(m0);
+    std::shared_lock<std::shared_mutex> lk1(m1);
+    lk1 = std::move(lk0);
+    assert(lk1.mutex() == &m0);
+    assert(lk1.owns_lock() == true);
+    assert(lk0.mutex() == nullptr);
+    assert(lk0.owns_lock() == false);
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/move_ctor.pass.cpp

@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// shared_lock(shared_lock&& u);
+
+#include <shared_mutex>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+std::shared_mutex m;
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<std::shared_mutex> lk0(m);
+    std::shared_lock<std::shared_mutex> lk = std::move(lk0);
+    assert(lk.mutex() == &m);
+    assert(lk.owns_lock() == true);
+    assert(lk0.mutex() == nullptr);
+    assert(lk0.owns_lock() == false);
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex.pass.cpp

@@ -0,0 +1,79 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// explicit shared_lock(mutex_type& m);
+
+#include <shared_mutex>
+#include <thread>
+#include <vector>
+#include <cstdlib>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+typedef std::chrono::system_clock Clock;
+typedef Clock::time_point time_point;
+typedef Clock::duration duration;
+typedef std::chrono::milliseconds ms;
+typedef std::chrono::nanoseconds ns;
+
+void f()
+{
+    time_point t0 = Clock::now();
+    time_point t1;
+    {
+    std::shared_lock<std::shared_mutex> ul(m);
+    t1 = Clock::now();
+    }
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+void g()
+{
+    time_point t0 = Clock::now();
+    time_point t1;
+    {
+    std::shared_lock<std::shared_mutex> ul(m);
+    t1 = Clock::now();
+    }
+    ns d = t1 - t0;
+    assert(d < ms(50));  // within 50ms
+}
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    m.lock();
+    std::vector<std::thread> v;
+    for (int i = 0; i < 5; ++i)
+        v.push_back(std::thread(f));
+    std::this_thread::sleep_for(ms(250));
+    m.unlock();
+    for (auto& t : v)
+        t.join();
+    m.lock_shared();
+    for (auto& t : v)
+        t = std::thread(g);
+    std::thread q(f);
+    std::this_thread::sleep_for(ms(250));
+    m.unlock_shared();
+    for (auto& t : v)
+        t.join();
+    q.join();
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_adopt_lock.pass.cpp

@@ -0,0 +1,28 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// shared_lock(mutex_type& m, adopt_lock_t);
+
+#include <shared_mutex>
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_mutex m;
+    m.lock();
+    std::shared_lock<std::shared_mutex> lk(m, std::adopt_lock);
+    assert(lk.mutex() == &m);
+    assert(lk.owns_lock() == true);
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_defer_lock.pass.cpp

@@ -0,0 +1,27 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// shared_lock(mutex_type& m, defer_lock_t);
+
+#include <shared_mutex>
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_mutex m;
+    std::shared_lock<std::shared_mutex> lk(m, std::defer_lock);
+    assert(lk.mutex() == &m);
+    assert(lk.owns_lock() == false);
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_duration.pass.cpp

@@ -0,0 +1,79 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// class timed_mutex;
+
+// template <class Rep, class Period>
+//   shared_lock(mutex_type& m, const chrono::duration<Rep, Period>& rel_time);
+
+#include <shared_mutex>
+#include <thread>
+#include <vector>
+#include <cstdlib>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+typedef std::chrono::steady_clock Clock;
+typedef Clock::time_point time_point;
+typedef Clock::duration duration;
+typedef std::chrono::milliseconds ms;
+typedef std::chrono::nanoseconds ns;
+
+void f1()
+{
+    time_point t0 = Clock::now();
+    std::shared_lock<std::shared_mutex> lk(m, ms(300));
+    assert(lk.owns_lock() == true);
+    time_point t1 = Clock::now();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+void f2()
+{
+    time_point t0 = Clock::now();
+    std::shared_lock<std::shared_mutex> lk(m, ms(250));
+    assert(lk.owns_lock() == false);
+    time_point t1 = Clock::now();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    {
+        m.lock();
+        std::vector<std::thread> v;
+        for (int i = 0; i < 5; ++i)
+            v.push_back(std::thread(f1));
+        std::this_thread::sleep_for(ms(250));
+        m.unlock();
+        for (auto& t : v)
+            t.join();
+    }
+    {
+        m.lock();
+        std::vector<std::thread> v;
+        for (int i = 0; i < 5; ++i)
+            v.push_back(std::thread(f2));
+        std::this_thread::sleep_for(ms(300));
+        m.unlock();
+        for (auto& t : v)
+            t.join();
+    }
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_time_point.pass.cpp

@@ -0,0 +1,79 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// class shared_mutex;
+
+// template <class Clock, class Duration>
+//   shared_lock(mutex_type& m, const chrono::time_point<Clock, Duration>& abs_time);
+
+#include <shared_mutex>
+#include <thread>
+#include <vector>
+#include <cstdlib>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+typedef std::chrono::steady_clock Clock;
+typedef Clock::time_point time_point;
+typedef Clock::duration duration;
+typedef std::chrono::milliseconds ms;
+typedef std::chrono::nanoseconds ns;
+
+void f1()
+{
+    time_point t0 = Clock::now();
+    std::shared_lock<std::shared_mutex> lk(m, Clock::now() + ms(300));
+    assert(lk.owns_lock() == true);
+    time_point t1 = Clock::now();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ns(50000000));  // within 50ms
+}
+
+void f2()
+{
+    time_point t0 = Clock::now();
+    std::shared_lock<std::shared_mutex> lk(m, Clock::now() + ms(250));
+    assert(lk.owns_lock() == false);
+    time_point t1 = Clock::now();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    {
+        m.lock();
+        std::vector<std::thread> v;
+        for (int i = 0; i < 5; ++i)
+            v.push_back(std::thread(f1));
+        std::this_thread::sleep_for(ms(250));
+        m.unlock();
+        for (auto& t : v)
+            t.join();
+    }
+    {
+        m.lock();
+        std::vector<std::thread> v;
+        for (int i = 0; i < 5; ++i)
+            v.push_back(std::thread(f2));
+        std::this_thread::sleep_for(ms(300));
+        m.unlock();
+        for (auto& t : v)
+            t.join();
+    }
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_try_to_lock.pass.cpp

@@ -0,0 +1,72 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// shared_lock(mutex_type& m, try_to_lock_t);
+
+#include <shared_mutex>
+#include <thread>
+#include <vector>
+#include <cstdlib>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+typedef std::chrono::system_clock Clock;
+typedef Clock::time_point time_point;
+typedef Clock::duration duration;
+typedef std::chrono::milliseconds ms;
+typedef std::chrono::nanoseconds ns;
+
+void f()
+{
+    time_point t0 = Clock::now();
+    {
+        std::shared_lock<std::shared_mutex> lk(m, std::try_to_lock);
+        assert(lk.owns_lock() == false);
+    }
+    {
+        std::shared_lock<std::shared_mutex> lk(m, std::try_to_lock);
+        assert(lk.owns_lock() == false);
+    }
+    {
+        std::shared_lock<std::shared_mutex> lk(m, std::try_to_lock);
+        assert(lk.owns_lock() == false);
+    }
+    while (true)
+    {
+        std::shared_lock<std::shared_mutex> lk(m, std::try_to_lock);
+        if (lk.owns_lock())
+            break;
+    }
+    time_point t1 = Clock::now();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(200));  // within 200ms
+}
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    m.lock();
+    std::vector<std::thread> v;
+    for (int i = 0; i < 5; ++i)
+        v.push_back(std::thread(f));
+    std::this_thread::sleep_for(ms(250));
+    m.unlock();
+    for (auto& t : v)
+        t.join();
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/lock.pass.cpp

@@ -0,0 +1,77 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// void lock();
+
+#include <shared_mutex>
+#include <thread>
+#include <vector>
+#include <cstdlib>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+typedef std::chrono::system_clock Clock;
+typedef Clock::time_point time_point;
+typedef Clock::duration duration;
+typedef std::chrono::milliseconds ms;
+typedef std::chrono::nanoseconds ns;
+
+void f()
+{
+    std::shared_lock<std::shared_mutex> lk(m, std::defer_lock);
+    time_point t0 = Clock::now();
+    lk.lock();
+    time_point t1 = Clock::now();
+    assert(lk.owns_lock() == true);
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(25));  // within 25ms
+    try
+    {
+        lk.lock();
+        assert(false);
+    }
+    catch (std::system_error& e)
+    {
+        assert(e.code().value() == EDEADLK);
+    }
+    lk.unlock();
+    lk.release();
+    try
+    {
+        lk.lock();
+        assert(false);
+    }
+    catch (std::system_error& e)
+    {
+        assert(e.code().value() == EPERM);
+    }
+}
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    m.lock();
+    std::vector<std::thread> v;
+    for (int i = 0; i < 5; ++i)
+        v.push_back(std::thread(f));
+    std::this_thread::sleep_for(ms(250));
+    m.unlock();
+    for (auto& t : v)
+        t.join();
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock.pass.cpp

@@ -0,0 +1,68 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// bool try_lock();
+
+#include <shared_mutex>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+bool try_lock_called = false;
+
+struct mutex
+{
+    bool try_lock_shared()
+    {
+        try_lock_called = !try_lock_called;
+        return try_lock_called;
+    }
+    void unlock_shared() {}
+};
+
+mutex m;
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<mutex> lk(m, std::defer_lock);
+    assert(lk.try_lock() == true);
+    assert(try_lock_called == true);
+    assert(lk.owns_lock() == true);
+    try
+    {
+        lk.try_lock();
+        assert(false);
+    }
+    catch (std::system_error& e)
+    {
+        assert(e.code().value() == EDEADLK);
+    }
+    lk.unlock();
+    assert(lk.try_lock() == false);
+    assert(try_lock_called == false);
+    assert(lk.owns_lock() == false);
+    lk.release();
+    try
+    {
+        lk.try_lock();
+        assert(false);
+    }
+    catch (std::system_error& e)
+    {
+        assert(e.code().value() == EPERM);
+    }
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock_for.pass.cpp

@@ -0,0 +1,73 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// template <class Rep, class Period>
+//   bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
+
+#include <shared_mutex>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+bool try_lock_for_called = false;
+
+typedef std::chrono::milliseconds ms;
+
+struct mutex
+{
+    template <class Rep, class Period>
+        bool try_lock_shared_for(const std::chrono::duration<Rep, Period>& rel_time)
+    {
+        assert(rel_time == ms(5));
+        try_lock_for_called = !try_lock_for_called;
+        return try_lock_for_called;
+    }
+    void unlock_shared() {}
+};
+
+mutex m;
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<mutex> lk(m, std::defer_lock);
+    assert(lk.try_lock_for(ms(5)) == true);
+    assert(try_lock_for_called == true);
+    assert(lk.owns_lock() == true);
+    try
+    {
+        lk.try_lock_for(ms(5));
+        assert(false);
+    }
+    catch (std::system_error& e)
+    {
+        assert(e.code().value() == EDEADLK);
+    }
+    lk.unlock();
+    assert(lk.try_lock_for(ms(5)) == false);
+    assert(try_lock_for_called == false);
+    assert(lk.owns_lock() == false);
+    lk.release();
+    try
+    {
+        lk.try_lock_for(ms(5));
+        assert(false);
+    }
+    catch (std::system_error& e)
+    {
+        assert(e.code().value() == EPERM);
+    }
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock_until.pass.cpp

@@ -0,0 +1,73 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// template <class Clock, class Duration>
+//   bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
+
+#include <shared_mutex>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+bool try_lock_until_called = false;
+
+struct mutex
+{
+    template <class Clock, class Duration>
+        bool try_lock_shared_until(const std::chrono::time_point<Clock, Duration>& abs_time)
+    {
+        typedef std::chrono::milliseconds ms;
+        assert(Clock::now() - abs_time < ms(5));
+        try_lock_until_called = !try_lock_until_called;
+        return try_lock_until_called;
+    }
+    void unlock_shared() {}
+};
+
+mutex m;
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    typedef std::chrono::steady_clock Clock;
+    std::shared_lock<mutex> lk(m, std::defer_lock);
+    assert(lk.try_lock_until(Clock::now()) == true);
+    assert(try_lock_until_called == true);
+    assert(lk.owns_lock() == true);
+    try
+    {
+        lk.try_lock_until(Clock::now());
+        assert(false);
+    }
+    catch (std::system_error& e)
+    {
+        assert(e.code().value() == EDEADLK);
+    }
+    lk.unlock();
+    assert(lk.try_lock_until(Clock::now()) == false);
+    assert(try_lock_until_called == false);
+    assert(lk.owns_lock() == false);
+    lk.release();
+    try
+    {
+        lk.try_lock_until(Clock::now());
+        assert(false);
+    }
+    catch (std::system_error& e)
+    {
+        assert(e.code().value() == EPERM);
+    }
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/unlock.pass.cpp

@@ -0,0 +1,60 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// void unlock();
+
+#include <shared_mutex>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+bool unlock_called = false;
+
+struct mutex
+{
+    void lock_shared() {}
+    void unlock_shared() {unlock_called = true;}
+};
+
+mutex m;
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<mutex> lk(m);
+    lk.unlock();
+    assert(unlock_called == true);
+    assert(lk.owns_lock() == false);
+    try
+    {
+        lk.unlock();
+        assert(false);
+    }
+    catch (std::system_error& e)
+    {
+        assert(e.code().value() == EPERM);
+    }
+    lk.release();
+    try
+    {
+        lk.unlock();
+        assert(false);
+    }
+    catch (std::system_error& e)
+    {
+        assert(e.code().value() == EPERM);
+    }
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/member_swap.pass.cpp

@@ -0,0 +1,43 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// void swap(shared_lock& u) noexcept;
+
+#include <shared_mutex>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+struct mutex
+{
+    void lock_shared() {}
+    void unlock_shared() {}
+};
+
+mutex m;
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<mutex> lk1(m);
+    std::shared_lock<mutex> lk2;
+    lk1.swap(lk2);
+    assert(lk1.mutex() == nullptr);
+    assert(lk1.owns_lock() == false);
+    assert(lk2.mutex() == &m);
+    assert(lk2.owns_lock() == true);
+    static_assert(noexcept(lk1.swap(lk2)), "member swap must be noexcept");
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/nonmember_swap.pass.cpp

@@ -0,0 +1,44 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// template <class Mutex>
+//   void swap(shared_lock<Mutex>& x, shared_lock<Mutex>& y) noexcept;
+
+#include <shared_mutex>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+struct mutex
+{
+    void lock_shared() {}
+    void unlock_shared() {}
+};
+
+mutex m;
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<mutex> lk1(m);
+    std::shared_lock<mutex> lk2;
+    swap(lk1, lk2);
+    assert(lk1.mutex() == nullptr);
+    assert(lk1.owns_lock() == false);
+    assert(lk2.mutex() == &m);
+    assert(lk2.owns_lock() == true);
+    static_assert(noexcept(swap(lk1, lk2)), "non-member swap must be noexcept");
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/release.pass.cpp

@@ -0,0 +1,51 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// mutex_type* release() noexcept;
+
+#include <shared_mutex>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+struct mutex
+{
+    static int lock_count;
+    static int unlock_count;
+    void lock_shared() {++lock_count;}
+    void unlock_shared() {++unlock_count;}
+};
+
+int mutex::lock_count = 0;
+int mutex::unlock_count = 0;
+
+mutex m;
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<mutex> lk(m);
+    assert(lk.mutex() == &m);
+    assert(lk.owns_lock() == true);
+    assert(mutex::lock_count == 1);
+    assert(mutex::unlock_count == 0);
+    assert(lk.release() == &m);
+    assert(lk.mutex() == nullptr);
+    assert(lk.owns_lock() == false);
+    assert(mutex::lock_count == 1);
+    assert(mutex::unlock_count == 0);
+    static_assert(noexcept(lk.release()), "release must be noexcept");
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/mutex.pass.cpp

@@ -0,0 +1,36 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// mutex_type *mutex() const noexcept;
+
+#include <shared_mutex>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<std::shared_mutex> lk0;
+    assert(lk0.mutex() == nullptr);
+    std::shared_lock<std::shared_mutex> lk1(m);
+    assert(lk1.mutex() == &m);
+    lk1.unlock();
+    assert(lk1.mutex() == &m);
+    static_assert(noexcept(lk0.mutex()), "mutex() must be noexcept");
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/op_bool.pass.cpp

@@ -0,0 +1,36 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// explicit operator bool() const noexcept;
+
+#include <shared_mutex>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<std::shared_mutex> lk0;
+    assert(static_cast<bool>(lk0) == false);
+    std::shared_lock<std::shared_mutex> lk1(m);
+    assert(static_cast<bool>(lk1) == true);
+    lk1.unlock();
+    assert(static_cast<bool>(lk1) == false);
+    static_assert(noexcept(static_cast<bool>(lk0)), "explicit operator bool() must be noexcept");
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/owns_lock.pass.cpp

@@ -0,0 +1,36 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// bool owns_lock() const noexcept;
+
+#include <shared_mutex>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<std::shared_mutex> lk0;
+    assert(lk0.owns_lock() == false);
+    std::shared_lock<std::shared_mutex> lk1(m);
+    assert(lk1.owns_lock() == true);
+    lk1.unlock();
+    assert(lk1.owns_lock() == false);
+    static_assert(noexcept(lk0.owns_lock()), "owns_lock must be noexcept");
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.shared/types.pass.cpp

@@ -0,0 +1,29 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// template <class Mutex>
+// class shared_lock
+// {
+// public:
+//     typedef Mutex mutex_type;
+//     ...
+// };
+
+#include <shared_mutex>
+#include <type_traits>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    static_assert((std::is_same<std::shared_lock<std::mutex>::mutex_type,
+                   std::mutex>::value), "");
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.mod/release.pass.cpp

@@ -11,7 +11,7 @@
 
 // template <class Mutex> class unique_lock;
 
-// void swap(unique_lock& u);
+// mutex_type* release() noexcept;
 
 #include <mutex>
 #include <cassert>

test/thread/thread.mutex/thread.mutex.requirements/thread.sharedmutex.requirements/nothing_to_do.pass.cpp

@@ -0,0 +1,12 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+int main()
+{
+}

test/thread/thread.mutex/thread.mutex.requirements/thread.sharedmutex.requirements/thread.sharedmutex.class/assign.fail.cpp

@@ -0,0 +1,27 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// class shared_mutex;
+
+// shared_mutex& operator=(const shared_mutex&) = delete;
+
+#include <shared_mutex>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_mutex m0;
+    std::shared_mutex m1;
+    m1 = m0;
+#else
+#   error
+#endif
+}

test/thread/thread.mutex/thread.mutex.requirements/thread.sharedmutex.requirements/thread.sharedmutex.class/copy.fail.cpp

@@ -0,0 +1,26 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// class shared_mutex;
+
+// shared_mutex(const shared_mutex&) = delete;
+
+#include <shared_mutex>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_mutex m0;
+    std::shared_mutex m1(m0);
+#else
+#   error
+#endif
+}

test/thread/thread.mutex/thread.mutex.requirements/thread.sharedmutex.requirements/thread.sharedmutex.class/default.pass.cpp

@@ -0,0 +1,23 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// class shared_mutex;
+
+// shared_mutex();
+
+#include <shared_mutex>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_mutex m;
+#endif
+}

test/thread/thread.mutex/thread.mutex.requirements/thread.sharedmutex.requirements/thread.sharedmutex.class/lock.pass.cpp

@@ -0,0 +1,52 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// class shared_mutex;
+
+// void lock();
+
+#include <shared_mutex>
+#include <thread>
+#include <cstdlib>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+typedef std::chrono::system_clock Clock;
+typedef Clock::time_point time_point;
+typedef Clock::duration duration;
+typedef std::chrono::milliseconds ms;
+typedef std::chrono::nanoseconds ns;
+
+void f()
+{
+    time_point t0 = Clock::now();
+    m.lock();
+    time_point t1 = Clock::now();
+    m.unlock();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    m.lock();
+    std::thread t(f);
+    std::this_thread::sleep_for(ms(250));
+    m.unlock();
+    t.join();
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.mutex.requirements/thread.sharedmutex.requirements/thread.sharedmutex.class/lock_shared.pass.cpp

@@ -0,0 +1,75 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// class shared_mutex;
+
+// void lock_shared();
+
+#include <shared_mutex>
+#include <thread>
+#include <vector>
+#include <cstdlib>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+typedef std::chrono::system_clock Clock;
+typedef Clock::time_point time_point;
+typedef Clock::duration duration;
+typedef std::chrono::milliseconds ms;
+typedef std::chrono::nanoseconds ns;
+
+void f()
+{
+    time_point t0 = Clock::now();
+    m.lock_shared();
+    time_point t1 = Clock::now();
+    m.unlock_shared();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+void g()
+{
+    time_point t0 = Clock::now();
+    m.lock_shared();
+    time_point t1 = Clock::now();
+    m.unlock_shared();
+    ns d = t1 - t0;
+    assert(d < ms(50));  // within 50ms
+}
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    m.lock();
+    std::vector<std::thread> v;
+    for (int i = 0; i < 5; ++i)
+        v.push_back(std::thread(f));
+    std::this_thread::sleep_for(ms(250));
+    m.unlock();
+    for (auto& t : v)
+        t.join();
+    m.lock_shared();
+    for (auto& t : v)
+        t = std::thread(g);
+    std::thread q(f);
+    std::this_thread::sleep_for(ms(250));
+    m.unlock_shared();
+    for (auto& t : v)
+        t.join();
+    q.join();
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.mutex.requirements/thread.sharedmutex.requirements/thread.sharedmutex.class/try_lock.pass.cpp

@@ -0,0 +1,56 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// class shared_mutex;
+
+// bool try_lock();
+
+#include <shared_mutex>
+#include <thread>
+#include <cstdlib>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+typedef std::chrono::system_clock Clock;
+typedef Clock::time_point time_point;
+typedef Clock::duration duration;
+typedef std::chrono::milliseconds ms;
+typedef std::chrono::nanoseconds ns;
+
+void f()
+{
+    time_point t0 = Clock::now();
+    assert(!m.try_lock());
+    assert(!m.try_lock());
+    assert(!m.try_lock());
+    while(!m.try_lock())
+        ;
+    time_point t1 = Clock::now();
+    m.unlock();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(200));  // within 200ms
+}
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    m.lock();
+    std::thread t(f);
+    std::this_thread::sleep_for(ms(250));
+    m.unlock();
+    t.join();
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.mutex.requirements/thread.sharedmutex.requirements/thread.sharedmutex.class/try_lock_for.pass.cpp

@@ -0,0 +1,71 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// class shared_mutex;
+
+// template <class Rep, class Period>
+//     bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
+
+#include <shared_mutex>
+#include <thread>
+#include <cstdlib>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+typedef std::chrono::steady_clock Clock;
+typedef Clock::time_point time_point;
+typedef Clock::duration duration;
+typedef std::chrono::milliseconds ms;
+typedef std::chrono::nanoseconds ns;
+
+void f1()
+{
+    time_point t0 = Clock::now();
+    assert(m.try_lock_for(ms(300)) == true);
+    time_point t1 = Clock::now();
+    m.unlock();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+void f2()
+{
+    time_point t0 = Clock::now();
+    assert(m.try_lock_for(ms(250)) == false);
+    time_point t1 = Clock::now();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    {
+        m.lock();
+        std::thread t(f1);
+        std::this_thread::sleep_for(ms(250));
+        m.unlock();
+        t.join();
+    }
+    {
+        m.lock();
+        std::thread t(f2);
+        std::this_thread::sleep_for(ms(300));
+        m.unlock();
+        t.join();
+    }
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.mutex.requirements/thread.sharedmutex.requirements/thread.sharedmutex.class/try_lock_shared.pass.cpp

@@ -0,0 +1,60 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// class shared_mutex;
+
+// bool try_lock_shared();
+
+#include <shared_mutex>
+#include <thread>
+#include <vector>
+#include <cstdlib>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+typedef std::chrono::system_clock Clock;
+typedef Clock::time_point time_point;
+typedef Clock::duration duration;
+typedef std::chrono::milliseconds ms;
+typedef std::chrono::nanoseconds ns;
+
+void f()
+{
+    time_point t0 = Clock::now();
+    assert(!m.try_lock_shared());
+    assert(!m.try_lock_shared());
+    assert(!m.try_lock_shared());
+    while(!m.try_lock_shared())
+        ;
+    time_point t1 = Clock::now();
+    m.unlock_shared();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(200));  // within 200ms
+}
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    m.lock();
+    std::vector<std::thread> v;
+    for (int i = 0; i < 5; ++i)
+        v.push_back(std::thread(f));
+    std::this_thread::sleep_for(ms(250));
+    m.unlock();
+    for (auto& t : v)
+        t.join();
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.mutex.requirements/thread.sharedmutex.requirements/thread.sharedmutex.class/try_lock_shared_for.pass.cpp

@@ -0,0 +1,78 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// class shared_mutex;
+
+// template <class Rep, class Period>
+//     bool try_lock_shared_for(const chrono::duration<Rep, Period>& rel_time);
+
+#include <shared_mutex>
+#include <thread>
+#include <vector>
+#include <cstdlib>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+typedef std::chrono::steady_clock Clock;
+typedef Clock::time_point time_point;
+typedef Clock::duration duration;
+typedef std::chrono::milliseconds ms;
+typedef std::chrono::nanoseconds ns;
+
+void f1()
+{
+    time_point t0 = Clock::now();
+    assert(m.try_lock_shared_for(ms(300)) == true);
+    time_point t1 = Clock::now();
+    m.unlock_shared();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+void f2()
+{
+    time_point t0 = Clock::now();
+    assert(m.try_lock_shared_for(ms(250)) == false);
+    time_point t1 = Clock::now();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    {
+        m.lock();
+        std::vector<std::thread> v;
+        for (int i = 0; i < 5; ++i)
+            v.push_back(std::thread(f1));
+        std::this_thread::sleep_for(ms(250));
+        m.unlock();
+        for (auto& t : v)
+            t.join();
+    }
+    {
+        m.lock();
+        std::vector<std::thread> v;
+        for (int i = 0; i < 5; ++i)
+            v.push_back(std::thread(f2));
+        std::this_thread::sleep_for(ms(300));
+        m.unlock();
+        for (auto& t : v)
+            t.join();
+    }
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.mutex.requirements/thread.sharedmutex.requirements/thread.sharedmutex.class/try_lock_shared_until.pass.cpp

@@ -0,0 +1,78 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// class shared_mutex;
+
+// template <class Clock, class Duration>
+//     bool try_lock_shared_until(const chrono::time_point<Clock, Duration>& abs_time);
+
+#include <shared_mutex>
+#include <thread>
+#include <vector>
+#include <cstdlib>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+typedef std::chrono::steady_clock Clock;
+typedef Clock::time_point time_point;
+typedef Clock::duration duration;
+typedef std::chrono::milliseconds ms;
+typedef std::chrono::nanoseconds ns;
+
+void f1()
+{
+    time_point t0 = Clock::now();
+    assert(m.try_lock_shared_until(Clock::now() + ms(300)) == true);
+    time_point t1 = Clock::now();
+    m.unlock_shared();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+void f2()
+{
+    time_point t0 = Clock::now();
+    assert(m.try_lock_shared_until(Clock::now() + ms(250)) == false);
+    time_point t1 = Clock::now();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    {
+        m.lock();
+        std::vector<std::thread> v;
+        for (int i = 0; i < 5; ++i)
+            v.push_back(std::thread(f1));
+        std::this_thread::sleep_for(ms(250));
+        m.unlock();
+        for (auto& t : v)
+            t.join();
+    }
+    {
+        m.lock();
+        std::vector<std::thread> v;
+        for (int i = 0; i < 5; ++i)
+            v.push_back(std::thread(f2));
+        std::this_thread::sleep_for(ms(300));
+        m.unlock();
+        for (auto& t : v)
+            t.join();
+    }
+#endif  // _LIBCPP_STD_VER > 11
+}

test/thread/thread.mutex/thread.mutex.requirements/thread.sharedmutex.requirements/thread.sharedmutex.class/try_lock_until.pass.cpp

@@ -0,0 +1,71 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <shared_mutex>
+
+// class shared_mutex;
+
+// template <class Clock, class Duration>
+//     bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
+
+#include <shared_mutex>
+#include <thread>
+#include <cstdlib>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_mutex m;
+
+typedef std::chrono::steady_clock Clock;
+typedef Clock::time_point time_point;
+typedef Clock::duration duration;
+typedef std::chrono::milliseconds ms;
+typedef std::chrono::nanoseconds ns;
+
+void f1()
+{
+    time_point t0 = Clock::now();
+    assert(m.try_lock_until(Clock::now() + ms(300)) == true);
+    time_point t1 = Clock::now();
+    m.unlock();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+void f2()
+{
+    time_point t0 = Clock::now();
+    assert(m.try_lock_until(Clock::now() + ms(250)) == false);
+    time_point t1 = Clock::now();
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    {
+        m.lock();
+        std::thread t(f1);
+        std::this_thread::sleep_for(ms(250));
+        m.unlock();
+        t.join();
+    }
+    {
+        m.lock();
+        std::thread t(f2);
+        std::this_thread::sleep_for(ms(300));
+        m.unlock();
+        t.join();
+    }
+#endif  // _LIBCPP_STD_VER > 11
+}