Imported gcc-4.4.3

[msp430-gcc.git] / libstdc++-v3 / src / atomic.cc

diff --git a/libstdc++-v3/src/atomic.cc b/libstdc++-v3/src/atomic.cc
new file mode 100644 (file)
index 0000000..9393307
--- /dev/null
+++ b/libstdc++-v3/src/atomic.cc
@@ -0,0 +1,116 @@
+// Support for atomic operations -*- C++ -*-
+
+// Copyright (C) 2008, 2009
+// 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.
+
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+// <http://www.gnu.org/licenses/>.
+
+#include "gstdint.h"
+#include <cstdatomic>
+#include <mutex>
+
+#define LOGSIZE 4
+
+namespace
+{
+#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
+  std::mutex&
+  get_atomic_mutex()
+  {
+    static std::mutex atomic_mutex;
+    return atomic_mutex;
+  }
+#endif
+
+  std::__atomic_flag_base volatile flag_table[ 1 << LOGSIZE ] =
+    {
+      ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT,
+      ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT,
+      ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT,
+      ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT,
+    };
+} // anonymous namespace
+
+namespace std
+{
+  namespace __atomic0
+  {
+    bool
+    atomic_flag::test_and_set(memory_order) volatile
+    {
+#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
+      lock_guard<mutex> __lock(get_atomic_mutex());
+#endif
+      bool result = _M_i;
+      _M_i = true;
+      return result;
+    }
+
+    void
+    atomic_flag::clear(memory_order) volatile
+    {
+#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
+      lock_guard<mutex> __lock(get_atomic_mutex());
+#endif
+      _M_i = false;
+    }
+  }
+
+  extern "C"
+  {
+    bool
+    atomic_flag_test_and_set_explicit(volatile __atomic_flag_base* __a,
+                                     memory_order __m)
+    {
+      volatile atomic_flag* d = static_cast<volatile atomic_flag*>(__a);
+      return d->test_and_set(__m);
+    }
+
+    void
+    atomic_flag_clear_explicit(volatile __atomic_flag_base* __a,
+                              memory_order __m)
+    {
+      volatile atomic_flag* d = static_cast<volatile atomic_flag*>(__a);
+      return d->clear(__m);
+    }
+
+    void
+    __atomic_flag_wait_explicit(volatile __atomic_flag_base* __a,
+                               memory_order __x)
+    {
+      while (atomic_flag_test_and_set_explicit(__a, __x))
+       { };
+    }
+
+    volatile __atomic_flag_base*
+    __atomic_flag_for_address(const volatile void* __z)
+    {
+      uintptr_t __u = reinterpret_cast<uintptr_t>(__z);
+      __u += (__u >> 2) + (__u << 4);
+      __u += (__u >> 7) + (__u << 5);
+      __u += (__u >> 17) + (__u << 13);
+      if (sizeof(uintptr_t) > 4)
+       __u += (__u >> 31);
+      __u &= ~((~uintptr_t(0)) << LOGSIZE);
+      return flag_table + __u;
+    }
+  } // extern "C"
+} // namespace std