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diff --git a/libstdc++-v3/include/parallel/workstealing.h b/libstdc++-v3/include/parallel/workstealing.h
new file mode 100644
index 000000000..5e90ae992
--- /dev/null
+++ b/libstdc++-v3/include/parallel/workstealing.h
@@ -0,0 +1,312 @@
+// -*- C++ -*-
+
+// Copyright (C) 2007, 2008, 2009, 2010 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/workstealing.h
+ *  @brief Parallelization of embarrassingly parallel execution by
+ *  means of work-stealing.
+ *
+ *  Work stealing is described in
+ *
+ *  R. D. Blumofe and C. E. Leiserson.
+ *  Scheduling multithreaded computations by work stealing.
+ *  Journal of the ACM, 46(5):720–748, 1999.
+ *
+ *  This file is a GNU parallel extension to the Standard C++ Library.
+ */
+
+// Written by Felix Putze.
+
+#ifndef _GLIBCXX_PARALLEL_WORKSTEALING_H
+#define _GLIBCXX_PARALLEL_WORKSTEALING_H 1
+
+#include <parallel/parallel.h>
+#include <parallel/random_number.h>
+#include <parallel/compatibility.h>
+
+namespace __gnu_parallel
+{
+
+#define _GLIBCXX_JOB_VOLATILE volatile
+
+  /** @brief One __job for a certain thread. */
+  template<typename _DifferenceTp>
+    struct _Job
+    {
+      typedef _DifferenceTp _DifferenceType;
+
+      /** @brief First element.
+       *
+       *  Changed by owning and stealing thread. By stealing thread,
+       *  always incremented. */
+      _GLIBCXX_JOB_VOLATILE _DifferenceType _M_first;
+
+      /** @brief Last element.
+       *
+       *  Changed by owning thread only. */
+      _GLIBCXX_JOB_VOLATILE _DifferenceType _M_last;
+
+      /** @brief Number of elements, i.e. @c _M_last-_M_first+1.
+       *
+       *  Changed by owning thread only. */
+      _GLIBCXX_JOB_VOLATILE _DifferenceType _M_load;
+    };
+
+  /** @brief Work stealing algorithm for random access iterators.
+    *
+    *  Uses O(1) additional memory. Synchronization at job lists is
+    *  done with atomic operations.
+    *  @param __begin Begin iterator of element sequence.
+    *  @param __end End iterator of element sequence.
+    *  @param __op User-supplied functor (comparator, predicate, adding
+    *  functor, ...).
+    *  @param __f Functor to @a process an element with __op (depends on
+    *  desired functionality, e. g. for std::for_each(), ...).
+    *  @param __r Functor to @a add a single __result to the already
+    *  processed elements (depends on functionality).
+    *  @param __base Base value for reduction.
+    *  @param __output Pointer to position where final result is written to
+    *  @param __bound Maximum number of elements processed (e. g. for
+    *  std::count_n()).
+    *  @return User-supplied functor (that may contain a part of the result).
+    */
+  template<typename _RAIter,
+           typename _Op,
+           typename _Fu,
+           typename _Red,
+           typename _Result>
+    _Op
+    __for_each_template_random_access_workstealing(_RAIter __begin,
+						   _RAIter __end, _Op __op,
+						   _Fu& __f, _Red __r,
+						   _Result __base,
+						   _Result& __output,
+      typename std::iterator_traits<_RAIter>::difference_type __bound)
+    {
+      _GLIBCXX_CALL(__end - __begin)
+
+      typedef std::iterator_traits<_RAIter> _TraitsType;
+      typedef typename _TraitsType::difference_type _DifferenceType;
+
+      const _Settings& __s = _Settings::get();
+
+      _DifferenceType __chunk_size =
+          static_cast<_DifferenceType>(__s.workstealing_chunk_size);
+
+      // How many jobs?
+      _DifferenceType __length = (__bound < 0) ? (__end - __begin) : __bound;
+
+      // To avoid false sharing in a cache line.
+      const int __stride = (__s.cache_line_size * 10
+			    / sizeof(_Job<_DifferenceType>) + 1);
+
+      // Total number of threads currently working.
+      _ThreadIndex __busy = 0;
+
+      _Job<_DifferenceType> *__job;
+
+      omp_lock_t __output_lock;
+      omp_init_lock(&__output_lock);
+
+      // Write base value to output.
+      __output = __base;
+
+      // No more threads than jobs, at least one thread.
+      _ThreadIndex __num_threads = __gnu_parallel::max<_ThreadIndex>
+	(1, __gnu_parallel::min<_DifferenceType>(__length,
+						 __get_max_threads()));
+
+#     pragma omp parallel shared(__busy) num_threads(__num_threads)
+      {
+#       pragma omp single
+	{
+	  __num_threads = omp_get_num_threads();
+
+	  // Create job description array.
+	  __job = new _Job<_DifferenceType>[__num_threads * __stride];
+	}
+
+	// Initialization phase.
+
+	// Flags for every thread if it is doing productive work.
+	bool __iam_working = false;
+
+	// Thread id.
+	_ThreadIndex __iam = omp_get_thread_num();
+
+	// This job.
+	_Job<_DifferenceType>& __my_job = __job[__iam * __stride];
+
+	// Random number (for work stealing).
+	_ThreadIndex __victim;
+
+	// Local value for reduction.
+	_Result __result = _Result();
+
+	// Number of elements to steal in one attempt.
+	_DifferenceType __steal;
+
+	// Every thread has its own random number generator
+	// (modulo __num_threads).
+	_RandomNumber __rand_gen(__iam, __num_threads);
+
+	// This thread is currently working.
+#       pragma omp atomic
+	++__busy;
+
+	__iam_working = true;
+
+	// How many jobs per thread? last thread gets the rest.
+	__my_job._M_first = static_cast<_DifferenceType>
+	  (__iam * (__length / __num_threads));
+
+	__my_job._M_last = (__iam == (__num_threads - 1)
+			    ? (__length - 1)
+			    : ((__iam + 1) * (__length / __num_threads) - 1));
+	__my_job._M_load = __my_job._M_last - __my_job._M_first + 1;
+
+	// Init result with _M_first value (to have a base value for reduction)
+	if (__my_job._M_first <= __my_job._M_last)
+	  {
+	    // Cannot use volatile variable directly.
+	    _DifferenceType __my_first = __my_job._M_first;
+	    __result = __f(__op, __begin + __my_first);
+	    ++__my_job._M_first;
+	    --__my_job._M_load;
+	  }
+
+	_RAIter __current;
+
+#       pragma omp barrier
+
+	// Actual work phase
+	// Work on own or stolen current start
+	while (__busy > 0)
+	  {
+	    // Work until no productive thread left.
+#           pragma omp flush(__busy)
+
+	    // Thread has own work to do
+	    while (__my_job._M_first <= __my_job._M_last)
+	      {
+		// fetch-and-add call
+		// Reserve current job block (size __chunk_size) in my queue.
+		_DifferenceType __current_job =
+		  __fetch_and_add<_DifferenceType>(&(__my_job._M_first),
+						   __chunk_size);
+
+		// Update _M_load, to make the three values consistent,
+		// _M_first might have been changed in the meantime
+		__my_job._M_load = __my_job._M_last - __my_job._M_first + 1;
+		for (_DifferenceType __job_counter = 0;
+		     __job_counter < __chunk_size
+		       && __current_job <= __my_job._M_last;
+		     ++__job_counter)
+		  {
+		    // Yes: process it!
+		    __current = __begin + __current_job;
+		    ++__current_job;
+
+		    // Do actual work.
+		    __result = __r(__result, __f(__op, __current));
+		  }
+
+#               pragma omp flush(__busy)
+	      }
+
+	    // After reaching this point, a thread's __job list is empty.
+	    if (__iam_working)
+	      {
+		// This thread no longer has work.
+#               pragma omp atomic
+		--__busy;
+
+		__iam_working = false;
+	      }
+
+	    _DifferenceType __supposed_first, __supposed_last,
+	                    __supposed_load;
+	    do
+	      {
+		// Find random nonempty deque (not own), do consistency check.
+		__yield();
+#               pragma omp flush(__busy)
+		__victim = __rand_gen();
+		__supposed_first = __job[__victim * __stride]._M_first;
+		__supposed_last = __job[__victim * __stride]._M_last;
+		__supposed_load = __job[__victim * __stride]._M_load;
+	      }
+	    while (__busy > 0
+		   && ((__supposed_load <= 0)
+		       || ((__supposed_first + __supposed_load - 1)
+			   != __supposed_last)));
+
+	    if (__busy == 0)
+	      break;
+
+	    if (__supposed_load > 0)
+	      {
+		// Has work and work to do.
+		// Number of elements to steal (at least one).
+		__steal = (__supposed_load < 2) ? 1 : __supposed_load / 2;
+
+		// Push __victim's current start forward.
+		_DifferenceType __stolen_first =
+		  __fetch_and_add<_DifferenceType>
+		  (&(__job[__victim * __stride]._M_first), __steal);
+		_DifferenceType __stolen_try = (__stolen_first + __steal
+						- _DifferenceType(1));
+
+		__my_job._M_first = __stolen_first;
+		__my_job._M_last = __gnu_parallel::min(__stolen_try,
+						       __supposed_last);
+		__my_job._M_load = __my_job._M_last - __my_job._M_first + 1;
+
+		// Has potential work again.
+#               pragma omp atomic
+		++__busy;
+		__iam_working = true;
+
+#               pragma omp flush(__busy)
+	      }
+#           pragma omp flush(__busy)
+	  } // end while __busy > 0
+	// Add accumulated result to output.
+	omp_set_lock(&__output_lock);
+	__output = __r(__output, __result);
+	omp_unset_lock(&__output_lock);
+      }
+
+      delete[] __job;
+
+      // Points to last element processed (needed as return value for
+      // some algorithms like transform)
+      __f._M_finish_iterator = __begin + __length;
+
+      omp_destroy_lock(&__output_lock);
+
+      return __op;
+    }
+} // end namespace
+
+#endif /* _GLIBCXX_PARALLEL_WORKSTEALING_H */