Index: pstl/trunk/include/pstl/internal/algorithm_fwd.h
===================================================================
--- pstl/trunk/include/pstl/internal/algorithm_fwd.h
+++ pstl/trunk/include/pstl/internal/algorithm_fwd.h
@@ -0,0 +1,1219 @@
+// -*- C++ -*-
+//===-- algorithm_fwd.h --------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef __PSTL_algorithm_fwd_H
+#define __PSTL_algorithm_fwd_H
+
+#include <type_traits>
+#include <utility>
+
+namespace __pstl
+{
+namespace internal
+{
+
+//------------------------------------------------------------------------
+// any_of
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _Pred>
+bool
+brick_any_of(const _ForwardIterator, const _ForwardIterator, _Pred,
+             /*__is_vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator, class _Pred>
+bool
+brick_any_of(const _ForwardIterator, const _ForwardIterator, _Pred,
+             /*__is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Pred, class _IsVector>
+bool pattern_any_of(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Pred, _IsVector,
+                    /*parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _Pred, class _IsVector>
+bool pattern_any_of(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Pred, _IsVector,
+                    /*parallel=*/std::true_type);
+#endif
+
+
+#if 0
+  // TODO does this even need forwarding?
+template <class _ForwardIterator, class _Size, class _Function>
+_ForwardIterator for_each_n_it_serial(_ForwardIterator, _Size, _Function);
+#endif
+
+//------------------------------------------------------------------------
+// walk1 (pseudo)
+//
+// walk1 evaluates f(x) for each dereferenced value x drawn from [first,last)
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _Function>
+void brick_walk1(_ForwardIterator, _ForwardIterator, _Function,
+                 /*vector=*/std::false_type) noexcept;
+
+template <class _RandomAccessIterator, class _Function>
+void brick_walk1(_RandomAccessIterator, _RandomAccessIterator, _Function,
+                 /*vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Function, class _IsVector>
+void pattern_walk1(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Function, _IsVector,
+                   /*parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _Function, class _IsVector>
+void pattern_walk1(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Function, _IsVector,
+                   /*parallel=*/std::true_type);
+#endif
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Brick>
+void pattern_walk_brick(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Brick,
+                        /*parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _Brick>
+void pattern_walk_brick(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Brick,
+                        /*parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// walk1_n
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _Size, class _Function>
+_ForwardIterator brick_walk1_n(_ForwardIterator, _Size, _Function,
+                               /*_IsVectorTag=*/std::false_type);
+
+template <class _RandomAccessIterator, class _DifferenceType, class _Function>
+_RandomAccessIterator brick_walk1_n(_RandomAccessIterator, _DifferenceType, _Function,
+                                    /*vectorTag=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Size, class _Function, class _IsVector>
+_ForwardIterator pattern_walk1_n(_ExecutionPolicy&&, _ForwardIterator, _Size, _Function, _IsVector,
+                                 /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy,class _RandomAccessIterator, class _Size, class _Function, class _IsVector>
+_RandomAccessIterator pattern_walk1_n(_ExecutionPolicy&&, _RandomAccessIterator, _Size, _Function, _IsVector,
+                                      /*is_parallel=*/std::true_type);
+#endif
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Size, class _Brick>
+_ForwardIterator pattern_walk_brick_n(_ExecutionPolicy&&, _ForwardIterator, _Size, _Brick,
+                                      /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _Size, class _Brick>
+_RandomAccessIterator pattern_walk_brick_n(_ExecutionPolicy&&, _RandomAccessIterator, _Size, _Brick,
+                                           /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// walk2 (pseudo)
+//
+// walk2 evaluates f(x,y) for deferenced values (x,y) drawn from [first1,last1) and [first2,...)
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _Function>
+_ForwardIterator2 brick_walk2(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _Function,
+                              /*vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _Function>
+_ForwardIterator2 brick_walk2(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _Function,
+                              /*vector=*/std::true_type) noexcept;
+
+template <class _ForwardIterator1, class _Size, class _ForwardIterator2, class _Function>
+_ForwardIterator2 brick_walk2_n(_ForwardIterator1, _Size, _ForwardIterator2, _Function,
+                                /*vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator1, class _Size, class _ForwardIterator2, class _Function>
+_ForwardIterator2 brick_walk2_n(_ForwardIterator1, _Size, _ForwardIterator2, _Function,
+                                /*vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _Function, class _IsVector>
+_ForwardIterator2 pattern_walk2(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _Function, _IsVector,
+                                /*parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _Function, class _IsVector>
+_ForwardIterator2 pattern_walk2(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _Function, _IsVector,
+                                /*parallel=*/std::true_type);
+#endif
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _Size, class _ForwardIterator2, class _Function, class _IsVector>
+_ForwardIterator2 pattern_walk2_n(_ExecutionPolicy&&, _ForwardIterator1, _Size, _ForwardIterator2, _Function, _IsVector,
+                                  /*parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator1, class _Size, class _RandomAccessIterator2, class _Function, class _IsVector>
+_RandomAccessIterator2 pattern_walk2_n(_ExecutionPolicy&&, _RandomAccessIterator1, _Size, _RandomAccessIterator2, _Function, _IsVector,
+                                       /*parallel=*/std::true_type);
+#endif
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _Brick>
+_ForwardIterator2 pattern_walk2_brick(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _Brick,
+                                      /*parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator1, class _RandomAccessIterator2, class _Brick>
+_RandomAccessIterator2 pattern_walk2_brick(_ExecutionPolicy&&, _RandomAccessIterator1, _RandomAccessIterator1, _RandomAccessIterator2,
+                                           _Brick,
+                                           /*parallel=*/std::true_type);
+#endif
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _Size, class _ForwardIterator2, class _Brick>
+_ForwardIterator2 pattern_walk2_brick_n(_ExecutionPolicy&&, _ForwardIterator1, _Size, _ForwardIterator2, _Brick,
+                                          /*parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator1, class _Size, class _RandomAccessIterator2, class _Brick>
+_RandomAccessIterator2 pattern_walk2_brick_n(_ExecutionPolicy&&, _RandomAccessIterator1, _Size, _RandomAccessIterator2, _Brick,
+                                             /*parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// walk3 (pseudo)
+//
+// walk3 evaluates f(x,y,z) for (x,y,z) drawn from [first1,last1), [first2,...), [first3,...)
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _ForwardIterator3, class _Function>
+_ForwardIterator3 brick_walk3(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator3, _Function,
+                              /*vector=*/std::false_type) noexcept;
+
+template <class _RandomAccessIterator1, class _RandomAccessIterator2, class _RandomAccessIterator3, class _Function>
+_RandomAccessIterator3 brick_walk3(_RandomAccessIterator1, _RandomAccessIterator1, _RandomAccessIterator2,
+                                   _RandomAccessIterator3, _Function,
+                                   /*vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _ForwardIterator3, class _Function, class _IsVector>
+_ForwardIterator3 pattern_walk3(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator3, _Function,
+                                _IsVector,
+                                /*parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator1, class _RandomAccessIterator2, class _RandomAccessIterator3, class _Function,
+          class _IsVector>
+_RandomAccessIterator3 pattern_walk3(_ExecutionPolicy&&, _RandomAccessIterator1, _RandomAccessIterator1, _RandomAccessIterator2,
+                                     _RandomAccessIterator3, _Function, _IsVector, /*parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// equal
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+bool brick_equal(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _BinaryPredicate,
+                 /* IsVector = */ std::false_type) noexcept;
+
+template <class _RandomAccessIterator1, class _RandomAccessIterator2, class _BinaryPredicate>
+bool brick_equal(_RandomAccessIterator1, _RandomAccessIterator1, _RandomAccessIterator2, _BinaryPredicate,
+                 /* is_vector = */ std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate, class _IsVector>
+bool pattern_equal(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _BinaryPredicate, _IsVector,
+                   /* is_parallel = */ std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator1, class _RandomAccessIterator2, class _BinaryPredicate, class _IsVector>
+bool pattern_equal(_ExecutionPolicy&&, _RandomAccessIterator1, _RandomAccessIterator1, _RandomAccessIterator2, _BinaryPredicate, _IsVector,
+                   /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// find_if
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _Predicate>
+_ForwardIterator brick_find_if(_ForwardIterator, _ForwardIterator, _Predicate,
+                               /*is_vector=*/std::false_type) noexcept;
+
+template <class _RandomAccessIterator, class _Predicate>
+_RandomAccessIterator brick_find_if(_RandomAccessIterator, _RandomAccessIterator, _Predicate,
+                                    /*is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate, class _IsVector>
+_ForwardIterator pattern_find_if(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Predicate, _IsVector,
+                                 /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate, class _IsVector>
+_ForwardIterator pattern_find_if(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Predicate, _IsVector,
+                                 /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// find_end
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_ForwardIterator1 brick_find_end(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                 _BinaryPredicate,
+                                 /*__is_vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_ForwardIterator1 brick_find_end(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                 _BinaryPredicate,
+                                 /*__is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate, class _IsVector>
+_ForwardIterator1 pattern_find_end(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                   _BinaryPredicate, _IsVector,
+                                   /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate, class _IsVector>
+_ForwardIterator1 pattern_find_end(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                   _BinaryPredicate, _IsVector,
+                                   /*is_parallel=*/std::true_type) noexcept;
+#endif
+
+//------------------------------------------------------------------------
+// find_first_of
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_ForwardIterator1 brick_find_first_of(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                      _BinaryPredicate,
+                                      /*__is_vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_ForwardIterator1 brick_find_first_of(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                      _BinaryPredicate,
+                                      /*__is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate, class _IsVector>
+_ForwardIterator1 pattern_find_first_of(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                        _BinaryPredicate, _IsVector, /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate, class _IsVector>
+_ForwardIterator1 pattern_find_first_of(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                        _BinaryPredicate, _IsVector, /*is_parallel=*/std::true_type) noexcept;
+#endif
+
+//------------------------------------------------------------------------
+// search
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_ForwardIterator1 brick_search(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                               _BinaryPredicate,
+                               /*vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_ForwardIterator1 brick_search(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                               _BinaryPredicate,
+                               /*vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate, class _IsVector>
+_ForwardIterator1 pattern_search(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                 _BinaryPredicate, _IsVector,
+                                 /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate, class _IsVector>
+_ForwardIterator1 pattern_search(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                 _BinaryPredicate, _IsVector,
+                                 /*is_parallel=*/std::true_type) noexcept;
+#endif
+
+//------------------------------------------------------------------------
+// search_n
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _Size, class _Tp, class _BinaryPredicate>
+_ForwardIterator
+brick_search_n(_ForwardIterator, _ForwardIterator, _Size, const _Tp&, _BinaryPredicate,
+               /*vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator, class _Size, class _Tp, class _BinaryPredicate>
+_ForwardIterator
+brick_search_n(_ForwardIterator, _ForwardIterator, _Size, const _Tp&, _BinaryPredicate,
+               /*vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Size, class _Tp, class _BinaryPredicate, class IsVector>
+_ForwardIterator
+pattern_search_n(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Size, const _Tp&, _BinaryPredicate, IsVector,
+                 /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _Size, class _Tp, class _BinaryPredicate, class IsVector>
+_RandomAccessIterator
+pattern_search_n(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _Size, const _Tp&, _BinaryPredicate, IsVector,
+                 /*is_parallel=*/std::true_type) noexcept;
+#endif
+
+//------------------------------------------------------------------------
+// copy_n
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _Size, class _OutputIterator>
+_OutputIterator brick_copy_n(_ForwardIterator, _Size, _OutputIterator,
+                             /*vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator, class _Size, class _OutputIterator>
+_OutputIterator brick_copy_n(_ForwardIterator, _Size, _OutputIterator,
+                             /*vector=*/std::true_type) noexcept;
+
+//------------------------------------------------------------------------
+// copy
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _OutputIterator>
+_OutputIterator brick_copy(_ForwardIterator, _ForwardIterator, _OutputIterator,
+                           /*vector=*/std::false_type) noexcept;
+
+template <class _RandomAccessIterator, class _OutputIterator>
+_OutputIterator brick_copy(_RandomAccessIterator, _RandomAccessIterator, _OutputIterator,
+                           /*vector=*/std::true_type) noexcept;
+
+//------------------------------------------------------------------------
+// move
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _OutputIterator>
+_OutputIterator brick_move(_ForwardIterator, _ForwardIterator, _OutputIterator,
+                           /*vector=*/std::false_type) noexcept;
+
+template <class _RandomAccessIterator, class _OutputIterator>
+_OutputIterator brick_move(_RandomAccessIterator, _RandomAccessIterator, _OutputIterator,
+                           /*vector=*/std::true_type) noexcept;
+
+//------------------------------------------------------------------------
+// swap_ranges
+//------------------------------------------------------------------------
+template <class _ForwardIterator, class _OutputIterator>
+_OutputIterator brick_swap_ranges(_ForwardIterator __first, _ForwardIterator __last, _OutputIterator __result,
+                                  /*vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator, class _OutputIterator>
+_OutputIterator brick_swap_ranges(_ForwardIterator __first, _ForwardIterator __last, _OutputIterator __result,
+                                  /*vector=*/std::true_type) noexcept;
+
+//------------------------------------------------------------------------
+// copy_if
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _OutputIterator, class _UnaryPredicate>
+_OutputIterator brick_copy_if(_ForwardIterator, _ForwardIterator, _OutputIterator, _UnaryPredicate,
+                              /*vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator, class _OutputIterator, class _UnaryPredicate>
+_OutputIterator brick_copy_if(_ForwardIterator, _ForwardIterator, _OutputIterator, _UnaryPredicate,
+                              /*vector=*/std::true_type) noexcept;
+
+template <class _DifferenceType, class _ForwardIterator, class _UnaryPredicate>
+std::pair<_DifferenceType, _DifferenceType>
+brick_calc_mask_1(_ForwardIterator, _ForwardIterator, bool* __restrict, _UnaryPredicate,
+                  /*vector=*/std::false_type) noexcept;
+template <class _DifferenceType, class _RandomAccessIterator, class _UnaryPredicate>
+std::pair<_DifferenceType, _DifferenceType>
+brick_calc_mask_1(_RandomAccessIterator, _RandomAccessIterator, bool* __restrict, _UnaryPredicate,
+                  /*vector=*/std::true_type) noexcept;
+
+template <class _ForwardIterator, class _OutputIterator>
+void
+brick_copy_by_mask(_ForwardIterator, _ForwardIterator, _OutputIterator, bool*,
+                   /*vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator, class _OutputIterator>
+void
+brick_copy_by_mask(_ForwardIterator, _ForwardIterator, _OutputIterator, bool* __restrict,
+                   /*vector=*/std::true_type) noexcept;
+
+template <class _ForwardIterator, class _OutputIterator1, class _OutputIterator2>
+void
+brick_partition_by_mask(_ForwardIterator, _ForwardIterator, _OutputIterator1, _OutputIterator2, bool*,
+                        /*vector=*/std::false_type) noexcept;
+
+template <class _RandomAccessIterator, class _OutputIterator1, class _OutputIterator2>
+void
+brick_partition_by_mask(_RandomAccessIterator, _RandomAccessIterator, _OutputIterator1, _OutputIterator2, bool*,
+                        /*vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _OutputIterator, class _UnaryPredicate, class _IsVector>
+_OutputIterator pattern_copy_if(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _OutputIterator, _UnaryPredicate, _IsVector,
+                                /*parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _OutputIterator, class _UnaryPredicate, class _IsVector>
+_OutputIterator pattern_copy_if(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _OutputIterator, _UnaryPredicate,
+                                _IsVector, /*parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// count
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _Predicate>
+typename std::iterator_traits<_ForwardIterator>::difference_type
+brick_count(_ForwardIterator, _ForwardIterator, _Predicate,
+            /* is_vector = */ std::true_type) noexcept;
+
+template <class _ForwardIterator, class _Predicate>
+typename std::iterator_traits<_ForwardIterator>::difference_type
+brick_count(_ForwardIterator, _ForwardIterator, _Predicate,
+            /* is_vector = */ std::false_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate, class _IsVector>
+typename std::iterator_traits<_ForwardIterator>::difference_type
+pattern_count(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Predicate,
+              /* is_parallel */ std::false_type, _IsVector) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate, class _IsVector>
+typename std::iterator_traits<_ForwardIterator>::difference_type
+pattern_count(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Predicate,
+              /* is_parallel */ std::true_type, _IsVector);
+#endif
+
+//------------------------------------------------------------------------
+// unique
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _BinaryPredicate>
+_ForwardIterator brick_unique(_ForwardIterator, _ForwardIterator, _BinaryPredicate,
+                              /*is_vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator, class _BinaryPredicate>
+_ForwardIterator brick_unique(_ForwardIterator, _ForwardIterator, _BinaryPredicate,
+                              /*is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _BinaryPredicate, class _IsVector>
+_ForwardIterator pattern_unique(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _BinaryPredicate, _IsVector,
+                                /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _BinaryPredicate, class _IsVector>
+_ForwardIterator pattern_unique(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _BinaryPredicate, _IsVector,
+                                /*is_parallel=*/std::true_type) noexcept;
+#endif
+
+//------------------------------------------------------------------------
+// unique_copy
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class OutputIterator, class _BinaryPredicate>
+OutputIterator brick_unique_copy(_ForwardIterator, _ForwardIterator, OutputIterator, _BinaryPredicate,
+                                 /*vector=*/std::false_type) noexcept;
+
+template <class _RandomAccessIterator, class _OutputIterator, class _BinaryPredicate>
+_OutputIterator brick_unique_copy(_RandomAccessIterator, _RandomAccessIterator, _OutputIterator, _BinaryPredicate,
+                                  /*vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class OutputIterator, class _BinaryPredicate, class _IsVector>
+OutputIterator pattern_unique_copy(_ForwardIterator, _ForwardIterator, OutputIterator, _BinaryPredicate, _IsVector,
+                                   /*parallel=*/std::false_type) noexcept;
+
+template <class _ExecutionPolicy, class _DifferenceType, class _RandomAccessIterator, class _BinaryPredicate>
+_DifferenceType
+brick_calc_mask_2(_RandomAccessIterator, _RandomAccessIterator, bool* __restrict, _BinaryPredicate,
+                  /*vector=*/std::false_type) noexcept;
+
+template <class _DifferenceType, class _RandomAccessIterator, class _BinaryPredicate>
+_DifferenceType
+brick_calc_mask_2(_RandomAccessIterator, _RandomAccessIterator, bool* __restrict, _BinaryPredicate,
+                  /*vector=*/std::true_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _OutputIterator, class _BinaryPredicate, class _IsVector>
+_OutputIterator pattern_unique_copy(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _OutputIterator, _BinaryPredicate,
+                                    _IsVector, /*parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// reverse
+//------------------------------------------------------------------------
+
+template <class _BidirectionalIterator>
+void brick_reverse(_BidirectionalIterator, _BidirectionalIterator,
+                   /*__is_vector=*/std::false_type) noexcept;
+
+template <class _BidirectionalIterator>
+void brick_reverse(_BidirectionalIterator, _BidirectionalIterator,
+                   /*__is_vector=*/std::true_type) noexcept;
+
+template <class _BidirectionalIterator>
+void brick_reverse(_BidirectionalIterator, _BidirectionalIterator, _BidirectionalIterator,
+                   /*is_vector=*/std::false_type) noexcept;
+
+template <class _BidirectionalIterator>
+void brick_reverse(_BidirectionalIterator, _BidirectionalIterator, _BidirectionalIterator,
+                   /*is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _BidirectionalIterator, class _IsVector>
+void pattern_reverse(_ExecutionPolicy&&, _BidirectionalIterator, _BidirectionalIterator, _IsVector,
+                     /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _BidirectionalIterator, class _IsVector>
+void pattern_reverse(_ExecutionPolicy&&, _BidirectionalIterator, _BidirectionalIterator, _IsVector,
+                     /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// reverse_copy
+//------------------------------------------------------------------------
+
+template <class _BidirectionalIterator, class _OutputIterator>
+_OutputIterator brick_reverse_copy(_BidirectionalIterator, _BidirectionalIterator, _OutputIterator,
+                                   /*is_vector=*/std::false_type) noexcept;
+
+template <class _BidirectionalIterator, class _OutputIterator>
+_OutputIterator brick_reverse_copy(_BidirectionalIterator, _BidirectionalIterator, _OutputIterator,
+                                   /*is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _BidirectionalIterator, class _OutputIterator, class _IsVector>
+_OutputIterator pattern_reverse_copy(_ExecutionPolicy&&, _BidirectionalIterator, _BidirectionalIterator, _OutputIterator, _IsVector,
+                                     /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _BidirectionalIterator, class _OutputIterator, class _IsVector>
+_OutputIterator pattern_reverse_copy(_ExecutionPolicy&&, _BidirectionalIterator, _BidirectionalIterator, _OutputIterator, _IsVector,
+                                     /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// rotate
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator>
+_ForwardIterator brick_rotate(_ForwardIterator, _ForwardIterator, _ForwardIterator,
+                              /*is_vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator>
+_ForwardIterator brick_rotate(_ForwardIterator, _ForwardIterator, _ForwardIterator,
+                              /*is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _IsVector>
+_ForwardIterator pattern_rotate(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _ForwardIterator, _IsVector,
+                                /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _IsVector>
+_ForwardIterator pattern_rotate(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _ForwardIterator, _IsVector,
+                                /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// rotate_copy
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _OutputIterator>
+_OutputIterator brick_rotate_copy(_ForwardIterator, _ForwardIterator, _ForwardIterator, _OutputIterator,
+                                  /*__is_vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator, class _OutputIterator>
+_OutputIterator brick_rotate_copy(_ForwardIterator, _ForwardIterator, _ForwardIterator, _OutputIterator,
+                                  /*__is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _OutputIterator, class _IsVector>
+_OutputIterator pattern_rotate_copy(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _ForwardIterator, _OutputIterator, _IsVector,
+                                    /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _OutputIterator, class _IsVector>
+_OutputIterator pattern_rotate_copy(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _ForwardIterator, _OutputIterator, _IsVector,
+                                    /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// is_partitioned
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _UnaryPredicate>
+bool brick_is_partitioned(_ForwardIterator, _ForwardIterator, _UnaryPredicate,
+                          /*is_vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator, class _UnaryPredicate>
+bool brick_is_partitioned(_ForwardIterator, _ForwardIterator, _UnaryPredicate,
+                          /*is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _UnaryPredicate, class _IsVector>
+bool pattern_is_partitioned(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _UnaryPredicate, _IsVector,
+                            /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _UnaryPredicate, class _IsVector>
+bool pattern_is_partitioned(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _UnaryPredicate, _IsVector,
+                            /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// partition
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _UnaryPredicate>
+_ForwardIterator brick_partition(_ForwardIterator, _ForwardIterator, _UnaryPredicate,
+                                 /*is_vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator, class _UnaryPredicate>
+_ForwardIterator brick_partition(_ForwardIterator, _ForwardIterator, _UnaryPredicate,
+                                 /*is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _UnaryPredicate, class _IsVector>
+_ForwardIterator pattern_partition(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _UnaryPredicate, _IsVector,
+                                   /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _UnaryPredicate, class _IsVector>
+_ForwardIterator pattern_partition(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _UnaryPredicate, _IsVector,
+                                   /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// stable_partition
+//------------------------------------------------------------------------
+
+template <class _BidirectionalIterator, class _UnaryPredicate>
+_BidirectionalIterator brick_stable_partition(_BidirectionalIterator, _BidirectionalIterator, _UnaryPredicate,
+                                              /*__is_vector=*/std::false_type) noexcept;
+
+template <class _BidirectionalIterator, class _UnaryPredicate>
+_BidirectionalIterator brick_stable_partition(_BidirectionalIterator, _BidirectionalIterator, _UnaryPredicate,
+                                              /*__is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _BidirectionalIterator, class _UnaryPredicate, class _IsVector>
+_BidirectionalIterator pattern_stable_partition(_ExecutionPolicy&&, _BidirectionalIterator, _BidirectionalIterator, _UnaryPredicate,
+                                                _IsVector,
+                                                /*is_parallelization=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _BidirectionalIterator, class _UnaryPredicate, class _IsVector>
+_BidirectionalIterator pattern_stable_partition(_ExecutionPolicy&&, _BidirectionalIterator, _BidirectionalIterator, _UnaryPredicate,
+                                                _IsVector,
+                                                /*is_parallelization=*/std::true_type) noexcept;
+#endif
+
+//------------------------------------------------------------------------
+// partition_copy
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _OutputIterator1, class _OutputIterator2, class _UnaryPredicate>
+std::pair<_OutputIterator1, _OutputIterator2> brick_partition_copy(_ForwardIterator, _ForwardIterator, _OutputIterator1,
+                                                                   _OutputIterator2, _UnaryPredicate,
+                                                                   /*is_vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator, class _OutputIterator1, class _OutputIterator2, class _UnaryPredicate>
+std::pair<_OutputIterator1, _OutputIterator2> brick_partition_copy(_ForwardIterator, _ForwardIterator, _OutputIterator1,
+                                                                   _OutputIterator2, _UnaryPredicate,
+                                                                   /*is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _OutputIterator1, class _OutputIterator2, class _UnaryPredicate,
+          class _IsVector>
+std::pair<_OutputIterator1, _OutputIterator2>
+pattern_partition_copy(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator,
+                       _OutputIterator1, _OutputIterator2,
+                       _UnaryPredicate, _IsVector,
+                                                                    /*is_parallelization=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _OutputIterator1, class _OutputIterator2, class _UnaryPredicate,
+          class _IsVector>
+std::pair<_OutputIterator1, _OutputIterator2>
+pattern_partition_copy(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator,
+                       _OutputIterator1, _OutputIterator2,
+                       _UnaryPredicate, _IsVector,
+                       /*is_parallelization=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// sort
+//------------------------------------------------------------------------
+
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _Compare, class _IsVector, class _IsMoveConstructible>
+void pattern_sort(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _Compare, _IsVector /*is_vector*/,
+                  /*is_parallel=*/std::false_type, _IsMoveConstructible) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _Compare, class _IsVector>
+void pattern_sort(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _Compare, _IsVector /*is_vector*/,
+                  /*is_parallel=*/std::true_type,
+                  /*is_move_constructible=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// stable_sort
+//------------------------------------------------------------------------
+
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _Compare, class _IsVector>
+void pattern_stable_sort(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _Compare, _IsVector /*is_vector*/,
+                         /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _Compare, class _IsVector>
+void pattern_stable_sort(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _Compare, _IsVector /*is_vector*/,
+                         /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// partial_sort
+//------------------------------------------------------------------------
+
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _Compare, class _IsVector>
+void pattern_partial_sort(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _RandomAccessIterator, _Compare, _IsVector,
+                          /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _Compare, class _IsVector>
+void pattern_partial_sort(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _RandomAccessIterator, _Compare, _IsVector,
+                          /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// partial_sort_copy
+//------------------------------------------------------------------------
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _RandomAccessIterator, class _Compare, class _IsVector>
+_RandomAccessIterator pattern_partial_sort_copy(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _RandomAccessIterator,
+                                                _RandomAccessIterator, _Compare, _IsVector,
+                                                /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _RandomAccessIterator, class _Compare, class _IsVector>
+_RandomAccessIterator pattern_partial_sort_copy(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _RandomAccessIterator,
+                                                _RandomAccessIterator, _Compare, _IsVector,
+                                                /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// adjacent_find
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _BinaryPredicate>
+_ForwardIterator
+brick_adjacent_find(_ForwardIterator, _ForwardIterator, _BinaryPredicate,
+                    /* IsVector = */ std::true_type, bool) noexcept;
+
+template <class _ForwardIterator, class _BinaryPredicate>
+_ForwardIterator
+brick_adjacent_find(_ForwardIterator, _ForwardIterator, _BinaryPredicate,
+                    /* IsVector = */ std::false_type, bool) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _BinaryPredicate, class _IsVector>
+_ForwardIterator
+pattern_adjacent_find(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _BinaryPredicate,
+                      /* is_parallel */ std::false_type, _IsVector, bool) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _BinaryPredicate, class _IsVector>
+_RandomAccessIterator
+pattern_adjacent_find(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _BinaryPredicate,
+                      /* is_parallel */ std::true_type, _IsVector, bool);
+#endif
+
+//------------------------------------------------------------------------
+// nth_element
+//------------------------------------------------------------------------
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _Compare, class _IsVector>
+void pattern_nth_element(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _RandomAccessIterator, _Compare, _IsVector,
+                          /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _Compare, class _IsVector>
+void pattern_nth_element(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _RandomAccessIterator, _Compare, _IsVector,
+                          /*is_parallel=*/std::true_type) noexcept;
+#endif
+
+//------------------------------------------------------------------------
+// fill, fill_n
+//------------------------------------------------------------------------
+template <class _ForwardIterator, class _Tp>
+void
+brick_fill(_ForwardIterator, _ForwardIterator, const _Tp&,
+           /* __is_vector = */ std::true_type) noexcept;
+
+template <class _ForwardIterator, class _Tp>
+void
+brick_fill(_ForwardIterator, _ForwardIterator, const _Tp&,
+           /* __is_vector = */ std::false_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Tp, class _IsVector>
+void
+pattern_fill(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, const _Tp&,
+             /*is_parallel=*/std::false_type, _IsVector) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _Tp, class _IsVector>
+_ForwardIterator
+pattern_fill(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, const _Tp&,
+             /*is_parallel=*/std::true_type, _IsVector);
+#endif
+
+template <class _OutputIterator, class _Size, class _Tp>
+_OutputIterator
+brick_fill_n(_OutputIterator, _Size, const _Tp&,
+             /* __is_vector = */ std::true_type) noexcept;
+
+template <class _OutputIterator, class _Size, class _Tp>
+_OutputIterator
+brick_fill_n(_OutputIterator, _Size, const _Tp&,
+             /* __is_vector = */ std::false_type) noexcept;
+
+template <class _ExecutionPolicy, class _OutputIterator, class _Size, class _Tp, class _IsVector>
+_OutputIterator
+pattern_fill_n(_ExecutionPolicy&&, _OutputIterator, _Size, const _Tp&,
+               /*is_parallel=*/std::false_type, _IsVector) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _OutputIterator, class _Size, class _Tp, class _IsVector>
+_OutputIterator
+pattern_fill_n(_ExecutionPolicy&&, _OutputIterator, _Size, const _Tp&,
+               /*is_parallel=*/std::true_type, _IsVector);
+#endif
+
+//------------------------------------------------------------------------
+// generate, generate_n
+//------------------------------------------------------------------------
+
+template <class _RandomAccessIterator, class _Generator>
+void brick_generate(_RandomAccessIterator, _RandomAccessIterator, _Generator,
+                    /* is_vector = */ std::true_type) noexcept;
+
+template <class _ForwardIterator, class _Generator>
+void brick_generate(_ForwardIterator, _ForwardIterator, _Generator,
+                    /* is_vector = */ std::false_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Generator, class _IsVector>
+void pattern_generate(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Generator,
+                      /*is_parallel=*/std::false_type, _IsVector) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _Generator, class _IsVector>
+_ForwardIterator pattern_generate(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Generator,
+                                  /*is_parallel=*/std::true_type, _IsVector);
+#endif
+
+template <class OutputIterator, class Size, class _Generator>
+OutputIterator brick_generate_n(OutputIterator, Size, _Generator,
+                                /* is_vector = */ std::true_type) noexcept;
+
+template <class OutputIterator, class Size, class _Generator>
+OutputIterator brick_generate_n(OutputIterator, Size, _Generator,
+                                /* is_vector = */ std::false_type) noexcept;
+
+template <class _ExecutionPolicy, class OutputIterator, class Size, class _Generator, class _IsVector>
+OutputIterator pattern_generate_n(_ExecutionPolicy&&, OutputIterator, Size, _Generator,
+                                  /*is_parallel=*/std::false_type, _IsVector) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class OutputIterator, class Size, class _Generator, class _IsVector>
+OutputIterator pattern_generate_n(_ExecutionPolicy&&, OutputIterator, Size, _Generator,
+                                  /*is_parallel=*/std::true_type, _IsVector);
+#endif
+
+//------------------------------------------------------------------------
+// remove
+//------------------------------------------------------------------------
+template <class _ForwardIterator, class _UnaryPredicate>
+_ForwardIterator brick_remove_if(_ForwardIterator, _ForwardIterator, _UnaryPredicate,
+                                  /* __is_vector = */ std::false_type) noexcept;
+
+template <class _RandomAccessIterator, class _UnaryPredicate>
+_RandomAccessIterator brick_remove_if(_RandomAccessIterator, _RandomAccessIterator, _UnaryPredicate,
+                                      /* __is_vector = */ std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _UnaryPredicate, class _IsVector>
+_ForwardIterator pattern_remove_if(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _UnaryPredicate, _IsVector,
+                                    /*is_parallel*/ std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _UnaryPredicate, class _IsVector>
+_ForwardIterator pattern_remove_if(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _UnaryPredicate, _IsVector,
+                                    /*is_parallel*/ std::true_type) noexcept;
+#endif
+
+//------------------------------------------------------------------------
+// merge
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare>
+_OutputIterator brick_merge(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2, _OutputIterator,
+                            _Compare,
+                            /* __is_vector = */ std::false_type) noexcept;
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare>
+_OutputIterator brick_merge(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2, _OutputIterator,
+                            _Compare,
+                            /* __is_vector = */ std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare, class _IsVector>
+_OutputIterator pattern_merge(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                              _OutputIterator, _Compare, _IsVector, /* is_parallel = */ std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator1, class _RandomAccessIterator2, class _OutputIterator, class _Compare,
+          class _IsVector>
+_OutputIterator pattern_merge(_ExecutionPolicy&&, _RandomAccessIterator1, _RandomAccessIterator1, _RandomAccessIterator2,
+                              _RandomAccessIterator2, _OutputIterator, _Compare, _IsVector,
+                              /* is_parallel = */ std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// inplace_merge
+//------------------------------------------------------------------------
+
+template <class _BidirectionalIterator, class _Compare>
+void brick_inplace_merge(_BidirectionalIterator, _BidirectionalIterator, _BidirectionalIterator, _Compare,
+                         /* __is_vector = */ std::false_type) noexcept;
+
+template <class _BidirectionalIterator, class _Compare>
+void brick_inplace_merge(_BidirectionalIterator, _BidirectionalIterator, _BidirectionalIterator, _Compare,
+                         /* __is_vector = */ std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _BidirectionalIterator, class _Compare, class _IsVector>
+void pattern_inplace_merge(_ExecutionPolicy&&, _BidirectionalIterator, _BidirectionalIterator, _BidirectionalIterator, _Compare, _IsVector,
+                           /* is_parallel = */ std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _BidirectionalIterator, class _Compare, class _IsVector>
+void pattern_inplace_merge(_ExecutionPolicy&&, _BidirectionalIterator, _BidirectionalIterator, _BidirectionalIterator, _Compare, _IsVector,
+                           /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// includes
+//------------------------------------------------------------------------
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _Compare, class _IsVector>
+bool pattern_includes(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2, _Compare, _IsVector,
+                      /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _Compare, class _IsVector>
+bool pattern_includes(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2, _Compare, _IsVector,
+                      /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// set_union
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare>
+_OutputIterator brick_set_union(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                _OutputIterator, _Compare,
+                                /*__is_vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare>
+_OutputIterator brick_set_union(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                _OutputIterator, _Compare,
+                                /*__is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare, class _IsVector>
+_OutputIterator pattern_set_union(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                  _OutputIterator, _Compare, _IsVector, /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare, class _IsVector>
+_OutputIterator pattern_set_union(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                  _OutputIterator, _Compare, _IsVector, /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// set_intersection
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare>
+_OutputIterator brick_set_intersection(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                       _OutputIterator, _Compare,
+                                       /*__is_vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare>
+_OutputIterator brick_set_intersection(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                       _OutputIterator, _Compare,
+                                       /*__is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare, class _IsVector>
+_OutputIterator pattern_set_intersection(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                         _OutputIterator, _Compare, _IsVector,
+                                         /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare, class _IsVector>
+_OutputIterator pattern_set_intersection(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                         _OutputIterator, _Compare, _IsVector, /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// set_difference
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare>
+_OutputIterator brick_set_difference(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                     _OutputIterator, _Compare,
+                                     /*__is_vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare>
+_OutputIterator brick_set_difference(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                     _OutputIterator, _Compare,
+                                     /*__is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare, class _IsVector>
+_OutputIterator pattern_set_difference(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                       _OutputIterator, _Compare, _IsVector, /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare, class _IsVector>
+_OutputIterator pattern_set_difference(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                       _OutputIterator, _Compare, _IsVector, /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// set_symmetric_difference
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare>
+_OutputIterator brick_set_symmetric_difference(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2,
+                                               _ForwardIterator2, _OutputIterator, _Compare,
+                                               /*__is_vector=*/std::false_type) noexcept;
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare>
+_OutputIterator brick_set_symmetric_difference(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2,
+                                               _ForwardIterator2, _OutputIterator, _Compare,
+                                               /*__is_vector=*/std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare, class _IsVector>
+_OutputIterator pattern_set_symmetric_difference(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2,
+                                                 _ForwardIterator2, _OutputIterator, _Compare, _IsVector,
+                                                 /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _OutputIterator, class _Compare, class _IsVector>
+_OutputIterator pattern_set_symmetric_difference(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2,
+                                                 _ForwardIterator2, _OutputIterator, _Compare, _IsVector,
+                                                 /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// is_heap_until
+//------------------------------------------------------------------------
+
+template <class _RandomAccessIterator, class _Compare>
+_RandomAccessIterator brick_is_heap_until(_RandomAccessIterator, _RandomAccessIterator, _Compare,
+                                          /* __is_vector = */ std::false_type) noexcept;
+
+template <class _RandomAccessIterator, class _Compare>
+_RandomAccessIterator brick_is_heap_until(_RandomAccessIterator, _RandomAccessIterator, _Compare,
+                                          /* __is_vector = */ std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _Compare, class _IsVector>
+_RandomAccessIterator pattern_is_heap_until(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _Compare, _IsVector,
+                                            /* is_parallel = */ std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _Compare, class _IsVector>
+_RandomAccessIterator pattern_is_heap_until(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _Compare, _IsVector,
+                                            /* is_parallel = */ std::true_type) noexcept;
+#endif
+
+//------------------------------------------------------------------------
+// min_element
+//------------------------------------------------------------------------
+
+template <typename _ForwardIterator, typename _Compare>
+_ForwardIterator brick_min_element(_ForwardIterator, _ForwardIterator, _Compare,
+                                   /* __is_vector = */ std::false_type) noexcept;
+
+template <typename _ForwardIterator, typename _Compare>
+_ForwardIterator brick_min_element(_ForwardIterator, _ForwardIterator, _Compare,
+                                   /* __is_vector = */ std::true_type) noexcept;
+
+template <typename _ExecutionPolicy, typename _ForwardIterator, typename _Compare, typename _IsVector>
+_ForwardIterator pattern_min_element(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Compare, _IsVector,
+                                     /* is_parallel = */ std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <typename _ExecutionPolicy, typename _RandomAccessIterator, typename _Compare, typename _IsVector>
+_RandomAccessIterator pattern_min_element(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator, _Compare, _IsVector,
+                                          /* is_parallel = */ std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// minmax_element
+//------------------------------------------------------------------------
+
+template <typename _ForwardIterator, typename _Compare>
+std::pair<_ForwardIterator, _ForwardIterator>
+brick_minmax_element(_ForwardIterator, _ForwardIterator, _Compare,
+                     /* __is_vector = */ std::false_type) noexcept;
+
+template <typename _ForwardIterator, typename _Compare>
+std::pair<_ForwardIterator, _ForwardIterator>
+brick_minmax_element(_ForwardIterator, _ForwardIterator, _Compare,
+                     /* __is_vector = */ std::true_type) noexcept;
+
+template <typename _ExecutionPolicy, typename _ForwardIterator, typename _Compare, typename _IsVector>
+std::pair<_ForwardIterator, _ForwardIterator>
+pattern_minmax_element(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Compare,
+                       _IsVector,
+                       /* is_parallel = */ std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <typename _ExecutionPolicy, typename _ForwardIterator, typename _Compare, typename _IsVector>
+std::pair<_ForwardIterator, _ForwardIterator>
+pattern_minmax_element(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Compare,
+                       _IsVector,
+                       /* is_parallel = */ std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// mismatch
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _Predicate>
+std::pair<_ForwardIterator1, _ForwardIterator2>
+brick_mismatch(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2,
+               _ForwardIterator2, _Predicate,
+               /* __is_vector = */ std::false_type) noexcept;
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _Predicate>
+std::pair<_ForwardIterator1, _ForwardIterator2>
+brick_mismatch(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2,
+               _ForwardIterator2, _Predicate,
+               /* __is_vector = */ std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _Predicate, class _IsVector>
+std::pair<_ForwardIterator1, _ForwardIterator2>
+pattern_mismatch(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2, _Predicate, _IsVector,
+                 /* is_parallel = */ std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator1, class _RandomAccessIterator2, class _Predicate, class _IsVector>
+std::pair<_RandomAccessIterator1, _RandomAccessIterator2>
+pattern_mismatch(_ExecutionPolicy&&, _RandomAccessIterator1, _RandomAccessIterator1, _RandomAccessIterator2, _RandomAccessIterator2,
+                 _Predicate, _IsVector, /* is_parallel = */ std::true_type) noexcept;
+#endif
+
+//------------------------------------------------------------------------
+// lexicographical_compare
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _Compare>
+bool brick_lexicographical_compare(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2, _Compare,
+                                   /* __is_vector = */ std::false_type) noexcept;
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _Compare>
+bool brick_lexicographical_compare(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2, _Compare,
+                                   /* __is_vector = */ std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _Compare, class _IsVector>
+bool pattern_lexicographical_compare(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                     _Compare, _IsVector, /* is_parallel = */ std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _Compare, class _IsVector>
+bool pattern_lexicographical_compare(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _ForwardIterator2,
+                                     _Compare, _IsVector, /* is_parallel = */ std::true_type) noexcept;
+#endif
+
+} // namespace internal
+} // namespace __pstl
+#endif /* __PSTL_algorithm_fwd_H */
Index: pstl/trunk/include/pstl/internal/glue_algorithm_impl.h
===================================================================
--- pstl/trunk/include/pstl/internal/glue_algorithm_impl.h
+++ pstl/trunk/include/pstl/internal/glue_algorithm_impl.h
@@ -14,8 +14,8 @@
 
 #include "execution_defs.h"
 #include "utils.h"
-#include "algorithm_impl.h"
-#include "numeric_impl.h" /* count and count_if use pattern_transform_reduce */
+#include "algorithm_fwd.h"
+#include "numeric_fwd.h" /* count and count_if use __pattern_transform_reduce */
 
 namespace std
 {
Index: pstl/trunk/include/pstl/internal/glue_execution_defs.h
===================================================================
--- pstl/trunk/include/pstl/internal/glue_execution_defs.h
+++ pstl/trunk/include/pstl/internal/glue_execution_defs.h
@@ -49,4 +49,8 @@
 } // namespace execution
 } // namespace std
 
+#include "algorithm_impl.h"
+#include "numeric_impl.h"
+#include "parallel_backend.h"
+
 #endif /* __PSTL_glue_execution_defs_H */
Index: pstl/trunk/include/pstl/internal/glue_memory_impl.h
===================================================================
--- pstl/trunk/include/pstl/internal/glue_memory_impl.h
+++ pstl/trunk/include/pstl/internal/glue_memory_impl.h
@@ -11,7 +11,7 @@
 #define __PSTL_glue_memory_impl_H
 
 #include "utils.h"
-#include "algorithm_impl.h"
+#include "algorithm_fwd.h"
 
 namespace std
 {
Index: pstl/trunk/include/pstl/internal/glue_numeric_impl.h
===================================================================
--- pstl/trunk/include/pstl/internal/glue_numeric_impl.h
+++ pstl/trunk/include/pstl/internal/glue_numeric_impl.h
@@ -13,7 +13,7 @@
 #include <functional>
 
 #include "utils.h"
-#include "numeric_impl.h"
+#include "numeric_fwd.h"
 
 namespace std
 {
Index: pstl/trunk/include/pstl/internal/numeric_fwd.h
===================================================================
--- pstl/trunk/include/pstl/internal/numeric_fwd.h
+++ pstl/trunk/include/pstl/internal/numeric_fwd.h
@@ -0,0 +1,142 @@
+// -*- C++ -*-
+//===-- numeric_fwd.h --------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef __PSTL_numeric_fwd_H
+#define __PSTL_numeric_fwd_H
+
+#include <type_traits>
+#include <utility>
+
+namespace __pstl
+{
+namespace internal
+{
+
+//------------------------------------------------------------------------
+// transform_reduce (version with two binary functions, according to draft N4659)
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _Tp, class _BinaryOperation1, class _BinaryOperation2>
+_Tp
+brick_transform_reduce(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _Tp, _BinaryOperation1,
+                       _BinaryOperation2,
+                       /*__is_vector=*/std::true_type) noexcept;
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _Tp, class _BinaryOperation1, class _BinaryOperation2>
+_Tp
+brick_transform_reduce(_ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _Tp, _BinaryOperation1,
+                       _BinaryOperation2,
+                       /*__is_vector=*/std::false_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator1, class _ForwardIterator2, class _Tp, class _BinaryOperation1, class _BinaryOperation2,
+          class _IsVector>
+_Tp
+pattern_transform_reduce(_ExecutionPolicy&&, _ForwardIterator1, _ForwardIterator1, _ForwardIterator2, _Tp, _BinaryOperation1,
+                         _BinaryOperation2, _IsVector,
+                         /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator1, class _RandomAccessIterator2, class _Tp, class _BinaryOperation1,
+          class _BinaryOperation2, class _IsVector>
+_Tp
+pattern_transform_reduce(_ExecutionPolicy&&, _RandomAccessIterator1, _RandomAccessIterator1, _RandomAccessIterator2, _Tp, _BinaryOperation1,
+                         _BinaryOperation2, _IsVector __is_vector, /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// transform_reduce (version with unary and binary functions)
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _Tp, class _UnaryOperation, class _BinaryOperation>
+_Tp
+brick_transform_reduce(_ForwardIterator, _ForwardIterator, _Tp, _BinaryOperation, _UnaryOperation,
+                       /*is_vector=*/std::true_type) noexcept;
+
+template <class _ForwardIterator, class _Tp, class _BinaryOperation, class _UnaryOperation>
+_Tp
+brick_transform_reduce(_ForwardIterator, _ForwardIterator, _Tp, _BinaryOperation, _UnaryOperation,
+                       /*is_vector=*/std::false_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Tp, class _BinaryOperation, class _UnaryOperation, class _IsVector>
+_Tp
+pattern_transform_reduce(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Tp, _BinaryOperation, _UnaryOperation, _IsVector,
+                         /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _Tp, class _BinaryOperation, class _UnaryOperation, class _IsVector>
+_Tp
+pattern_transform_reduce(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _Tp, _BinaryOperation, _UnaryOperation, _IsVector,
+                         /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// transform_exclusive_scan
+//
+// walk3 evaluates f(x,y,z) for (x,y,z) drawn from [first1,last1), [first2,...), [first3,...)
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _OutputIterator, class _UnaryOperation, class _Tp, class _BinaryOperation>
+std::pair<_OutputIterator, _Tp> brick_transform_scan(_ForwardIterator, _ForwardIterator, _OutputIterator,
+                                                     _UnaryOperation, _Tp, _BinaryOperation,
+                                                     /*Inclusive*/ std::false_type) noexcept;
+
+template <class _ForwardIterator, class _OutputIterator, class _UnaryOperation, class _Tp, class _BinaryOperation>
+std::pair<_OutputIterator, _Tp> brick_transform_scan(_ForwardIterator, _ForwardIterator, _OutputIterator,
+                                                     _UnaryOperation, _Tp, _BinaryOperation,
+                                                     /*Inclusive*/ std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _OutputIterator, class _UnaryOperation, class _Tp, class _BinaryOperation,
+          class _Inclusive, class _IsVector>
+_OutputIterator pattern_transform_scan(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _OutputIterator, _UnaryOperation, _Tp,
+                                       _BinaryOperation, _Inclusive, _IsVector,
+                                       /*is_parallel=*/std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _OutputIterator, class _UnaryOperation, class _Tp,
+          class _BinaryOperation, class _Inclusive, class _IsVector>
+typename std::enable_if<!std::is_floating_point<_Tp>::value, _OutputIterator>::type
+pattern_transform_scan(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator,
+                       _OutputIterator, _UnaryOperation, _Tp, _BinaryOperation,
+                       _Inclusive, _IsVector, /*is_parallel=*/std::true_type);
+#endif
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _OutputIterator, class _UnaryOperation, class _Tp,
+          class _BinaryOperation, class _Inclusive, class _IsVector>
+typename std::enable_if<std::is_floating_point<_Tp>::value, _OutputIterator>::type
+pattern_transform_scan(_ExecutionPolicy&&, _RandomAccessIterator, _RandomAccessIterator,
+                       _OutputIterator, _UnaryOperation, _Tp, _BinaryOperation,
+                       _Inclusive, _IsVector, /*is_parallel=*/std::true_type);
+#endif
+
+//------------------------------------------------------------------------
+// adjacent_difference
+//------------------------------------------------------------------------
+
+template <class _ForwardIterator, class _OutputIterator, class _BinaryOperation>
+_OutputIterator brick_adjacent_difference(_ForwardIterator, _ForwardIterator, _OutputIterator, _BinaryOperation,
+                                          /*is_vector*/ std::false_type) noexcept;
+
+template <class _ForwardIterator, class _OutputIterator, class _BinaryOperation>
+_OutputIterator brick_adjacent_difference(_ForwardIterator, _ForwardIterator, _OutputIterator, _BinaryOperation,
+                                          /*is_vector*/ std::true_type) noexcept;
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _OutputIterator, class _BinaryOperation, class _IsVector>
+_OutputIterator pattern_adjacent_difference(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _OutputIterator, _BinaryOperation,
+                                            _IsVector, /*is_parallel*/ std::false_type) noexcept;
+
+#if __PSTL_USE_PAR_POLICIES
+template <class _ExecutionPolicy, class _ForwardIterator, class _OutputIterator, class _BinaryOperation, class _IsVector>
+_OutputIterator pattern_adjacent_difference(_ExecutionPolicy&&, _ForwardIterator, _ForwardIterator, _OutputIterator, _BinaryOperation,
+                                            _IsVector, /*is_parallel*/ std::true_type);
+#endif
+
+} // namespace internal
+} // namespace __pstl
+#endif /* __PSTL_numeric_fwd_H */
Index: pstl/trunk/include/pstl/internal/numeric_impl.h
===================================================================
--- pstl/trunk/include/pstl/internal/numeric_impl.h
+++ pstl/trunk/include/pstl/internal/numeric_impl.h
@@ -14,9 +14,9 @@
 #include <type_traits>
 #include <numeric>
 
-#include "pstl_config.h"
 #include "execution_impl.h"
 #include "unseq_backend_simd.h"
+#include "algorithm_fwd.h"
 
 #if __PSTL_USE_PAR_POLICIES
 #include "parallel_backend.h"
Index: pstl/trunk/include/pstl/internal/unseq_backend_simd.h
===================================================================
--- pstl/trunk/include/pstl/internal/unseq_backend_simd.h
+++ pstl/trunk/include/pstl/internal/unseq_backend_simd.h
@@ -12,7 +12,6 @@
 
 #include <type_traits>
 
-#include "pstl_config.h"
 #include "utils.h"
 
 // This header defines the minimum set of vector routines required
Index: pstl/trunk/test/std/algorithms/alg.modifying.operations/transform_binary.pass.cpp
===================================================================
--- pstl/trunk/test/std/algorithms/alg.modifying.operations/transform_binary.pass.cpp
+++ pstl/trunk/test/std/algorithms/alg.modifying.operations/transform_binary.pass.cpp
@@ -10,8 +10,8 @@
 #include "support/pstl_test_config.h"
 
 #ifdef PSTL_STANDALONE_TESTS
-#include "pstl/algorithm"
 #include "pstl/execution"
+#include "pstl/algorithm"
 #else
 #include <execution>
 #include <algorithm>
Index: pstl/trunk/test/std/algorithms/alg.modifying.operations/transform_unary.pass.cpp
===================================================================
--- pstl/trunk/test/std/algorithms/alg.modifying.operations/transform_unary.pass.cpp
+++ pstl/trunk/test/std/algorithms/alg.modifying.operations/transform_unary.pass.cpp
@@ -10,8 +10,8 @@
 #include "support/pstl_test_config.h"
 
 #ifdef PSTL_STANDALONE_TESTS
-#include "pstl/algorithm"
 #include "pstl/execution"
+#include "pstl/algorithm"
 #else
 #include <execution>
 #include <algorithm>