1 files changed, 52 insertions, 0 deletions
diff --git a/libstdc++-v3/config/cpu/i486/atomicity.h b/libstdc++-v3/config/cpu/i486/atomicity.h
new file mode 100644
index 000000000..602cbb711
--- /dev/null
+++ b/libstdc++-v3/config/cpu/i486/atomicity.h
@@ -0,0 +1,52 @@
+// Low-level functions for atomic operations: x86, x >= 4 version  -*- C++ -*-
+
+// Copyright (C) 1999, 2000, 2001, 2004, 2005, 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 <ext/atomicity.h>
+
+namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
+{
+_GLIBCXX_BEGIN_NAMESPACE_VERSION
+
+  _Atomic_word 
+  __attribute__ ((__unused__))
+  __exchange_and_add(volatile _Atomic_word* __mem, int __val) throw ()
+  {
+    register _Atomic_word __result;
+    __asm__ __volatile__ ("lock; xadd{l} {%0,%1|%1,%0}"
+			  : "=r" (__result), "=m" (*__mem) 
+			  : "0" (__val), "m" (*__mem));
+    return __result;
+  }
+  
+  void
+  __attribute__ ((__unused__))
+  __atomic_add(volatile _Atomic_word* __mem, int __val) throw ()
+  {
+    __asm__ __volatile__ ("lock; add{l} {%1,%0|%0,%1}"
+			  : "=m" (*__mem) : "ir" (__val), "m" (*__mem));
+  }
+
+_GLIBCXX_END_NAMESPACE_VERSION
+} // namespace
+