| // { dg-options "-std=gnu++2a" } |
| // { dg-do run { target c++2a } } |
| // { dg-require-gthreads "" } |
| // { dg-additional-options "-pthread" { target pthread } } |
| // { dg-add-options libatomic } |
| |
| // Copyright (C) 2021-2023 Free Software Foundation, Inc. |
| // |
| // This file is part of the GNU ISO C++ Library. This library is free |
| // software; you can redistribute it and/or modify it under the |
| // terms of the GNU General Public License as published by the |
| // Free Software Foundation; either version 3, or (at your option) |
| // any later version. |
| |
| // This library is distributed in the hope that it will be useful, |
| // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| // GNU General Public License for more details. |
| |
| // You should have received a copy of the GNU General Public License along |
| // with this library; see the file COPYING3. If not see |
| // <http://www.gnu.org/licenses/>. |
| |
| #include <atomic> |
| #include <future> |
| |
| #include <testsuite_hooks.h> |
| |
| template <typename T> |
| struct atomics_sharing_same_waiter |
| { |
| std::atomic<T> tmp[49 * 4] = {}; |
| std::atomic<T>* a[4] = { |
| { &tmp[0] }, |
| { &tmp[16 * 4] }, |
| { &tmp[32 * 4] }, |
| { &tmp[48 * 4] } |
| }; |
| }; |
| |
| constexpr unsigned key(void * a) |
| { |
| constexpr uintptr_t ct = 16; |
| return (uintptr_t(a) >> 2) % ct; |
| } |
| |
| int |
| main() |
| { |
| // all atomic share the same waiter |
| // atomics_sharing_same_waiter<char> atomics; |
| atomics_sharing_same_waiter<char> atomics; |
| for (auto& atom : atomics.a) |
| { |
| atom->store(0); |
| } |
| |
| auto a = &std::__detail::__waiter_pool_base::_S_for(reinterpret_cast<char *>(atomics.a[0])); |
| auto b = &std::__detail::__waiter_pool_base::_S_for(reinterpret_cast<char *>(atomics.a[1])); |
| VERIFY( a == b ); |
| |
| auto fut0 = std::async(std::launch::async, [&] { atomics.a[0]->wait(0); }); |
| auto fut1 = std::async(std::launch::async, [&] { atomics.a[1]->wait(0); }); |
| auto fut2 = std::async(std::launch::async, [&] { atomics.a[2]->wait(0); }); |
| auto fut3 = std::async(std::launch::async, [&] { atomics.a[3]->wait(0); }); |
| |
| // make sure the all threads already await |
| std::this_thread::sleep_for(std::chrono::milliseconds{100}); |
| |
| atomics.a[2]->store(1); |
| atomics.a[2]->notify_one(); |
| |
| VERIFY(std::future_status::timeout == fut0.wait_for(std::chrono::milliseconds{100})); |
| VERIFY(atomics.a[0]->load() == 0); |
| |
| VERIFY(std::future_status::timeout == fut1.wait_for(std::chrono::milliseconds{100})); |
| VERIFY(atomics.a[1]->load() == 0); |
| |
| VERIFY(std::future_status::ready == fut2.wait_for(std::chrono::milliseconds{100})); |
| VERIFY(atomics.a[2]->load() == 1); |
| |
| VERIFY(std::future_status::timeout == fut3.wait_for(std::chrono::milliseconds{100})); |
| VERIFY(atomics.a[3]->load() == 0); |
| |
| atomics.a[0]->store(1); |
| atomics.a[0]->notify_one(); |
| atomics.a[1]->store(1); |
| atomics.a[1]->notify_one(); |
| atomics.a[3]->store(1); |
| atomics.a[3]->notify_one(); |
| |
| return 0; |
| } |