libcxx/test/support/cmpxchg_loop.h

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include <atomic>
  10
  11 template <class A>
  12 bool cmpxchg_weak_loop(A& atomic, typename A::value_type& expected, typename A::value_type desired) {
  13   for (int i = 0; i < 10; i++) {
  14     if (atomic.compare_exchange_weak(expected, desired) == true) {
  15       return true;
  16     }
  17   }
  18
  19   return false;
  20 }
  21
  22 template <class A>
  23 bool cmpxchg_weak_loop(A& atomic, typename A::value_type& expected, typename A::value_type desired,
  24                        std::memory_order success,
  25                        std::memory_order failure) {
  26   for (int i = 0; i < 10; i++) {
  27     if (atomic.compare_exchange_weak(expected, desired, success,
  28                                      failure) == true) {
  29       return true;
  30     }
  31   }
  32
  33   return false;
  34 }
  35
  36 template <class A>
  37 bool c_cmpxchg_weak_loop(A* atomic, typename A::value_type* expected, typename A::value_type desired) {
  38   for (int i = 0; i < 10; i++) {
  39     if (std::atomic_compare_exchange_weak(atomic, expected, desired) == true) {
  40       return true;
  41     }
  42   }
  43
  44   return false;
  45 }
  46
  47 template <class A>
  48 bool c_cmpxchg_weak_loop(A* atomic, typename A::value_type* expected, typename A::value_type desired,
  49                          std::memory_order success,
  50                          std::memory_order failure) {
  51   for (int i = 0; i < 10; i++) {
  52     if (std::atomic_compare_exchange_weak_explicit(atomic, expected, desired,
  53                                                    success, failure) == true) {
  54       return true;
  55     }
  56   }
  57
  58   return false;
  59 }