sdk: build libsupc++ from libstdc++ source

git-svn-id: svn://kolibrios.org@5134 a494cfbc-eb01-0410-851d-a64ba20cac60

contrib/sdk/sources/libstdc++-v3/include/parallel/compatibility.h

@@ -0,0 +1,131 @@
+// -*- C++ -*-
+
+// Copyright (C) 2007-2013 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/>.
+
+/** @file parallel/compatibility.h
+ *  @brief Compatibility layer, mostly concerned with atomic operations.
+ *
+ *  This file is a GNU parallel extension to the Standard C++ Library
+ *  and contains implementation details for the library's internal use.
+ */
+
+// Written by Felix Putze.
+
+#ifndef _GLIBCXX_PARALLEL_COMPATIBILITY_H
+#define _GLIBCXX_PARALLEL_COMPATIBILITY_H 1
+
+#include <parallel/types.h>
+#include <parallel/base.h>
+
+#if !defined(_WIN32) || defined (__CYGWIN__)
+#include <sched.h>
+#endif
+
+#ifdef __MINGW32__
+// Including <windows.h> will drag in all the windows32 names.  Since
+// that can cause user code portability problems, we just declare the
+// one needed function here.
+extern "C"
+__attribute((dllimport)) void __attribute__((stdcall)) Sleep (unsigned long);
+#endif
+
+namespace __gnu_parallel
+{
+  template<typename _Tp>
+    inline _Tp
+    __add_omp(volatile _Tp* __ptr, _Tp __addend)
+    {
+      int64_t __res;
+#pragma omp critical
+      {
+	__res = *__ptr;
+	*(__ptr) += __addend;
+      }
+      return __res;
+    }
+
+  /** @brief Add a value to a variable, atomically.
+   *
+   *  @param __ptr Pointer to a signed integer.
+   *  @param __addend Value to add.
+   */
+  template<typename _Tp>
+    inline _Tp
+    __fetch_and_add(volatile _Tp* __ptr, _Tp __addend)
+    {
+      if (__atomic_always_lock_free(sizeof(_Tp), __ptr))
+	return __atomic_fetch_add(__ptr, __addend, __ATOMIC_ACQ_REL);
+      return __add_omp(__ptr, __addend);
+    }
+
+  template<typename _Tp>
+    inline bool
+    __cas_omp(volatile _Tp* __ptr, _Tp __comparand, _Tp __replacement)
+    {
+      bool __res = false;
+#pragma omp critical
+      {
+	if (*__ptr == __comparand)
+	  {
+	    *__ptr = __replacement;
+	    __res = true;
+	  }
+      }
+      return __res;
+    }
+
+  /** @brief Compare-and-swap
+   *
+   * Compare @c *__ptr and @c __comparand. If equal, let @c
+   * *__ptr=__replacement and return @c true, return @c false otherwise.
+   *
+   *  @param __ptr Pointer to signed integer.
+   *  @param __comparand Compare value.
+   *  @param __replacement Replacement value.
+   */
+  template<typename _Tp>
+    inline bool
+    __compare_and_swap(volatile _Tp* __ptr, _Tp __comparand, _Tp __replacement)
+    {
+      if (__atomic_always_lock_free(sizeof(_Tp), __ptr))
+	return __atomic_compare_exchange_n(__ptr, &__comparand, __replacement,
+					   false, __ATOMIC_ACQ_REL,
+					   __ATOMIC_RELAXED);
+      return __cas_omp(__ptr, __comparand, __replacement);
+    }
+
+  /** @brief Yield control to another thread, without waiting for
+   *  the end of the time slice.
+   */
+  inline void
+  __yield()
+  {
+#if defined (_WIN32) && !defined (__CYGWIN__)
+    Sleep(0);
+#else
+    sched_yield();
+#endif
+  }
+} // end namespace
+
+#endif /* _GLIBCXX_PARALLEL_COMPATIBILITY_H */