diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -237,6 +237,19 @@
   __memory/unique_ptr.h
   __memory/uses_allocator.h
   __mutex_base
+  __numeric/accumulate.h
+  __numeric/adjacent_difference.h
+  __numeric/exclusive_scan.h
+  __numeric/gcd_lcm.h
+  __numeric/inclusive_scan.h
+  __numeric/inner_product.h
+  __numeric/iota.h
+  __numeric/midpoint.h
+  __numeric/partial_sum.h
+  __numeric/reduce.h
+  __numeric/transform_exclusive_scan.h
+  __numeric/transform_inclusive_scan.h
+  __numeric/transform_reduce.h
   __node_handle
   __nullptr
   __random/bernoulli_distribution.h
diff --git a/libcxx/include/__numeric/accumulate.h b/libcxx/include/__numeric/accumulate.h
new file mode 100644
--- /dev/null
+++ b/libcxx/include/__numeric/accumulate.h
@@ -0,0 +1,52 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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 _LIBCPP___NUMERIC_ACCUMULATE_H
+#define _LIBCPP___NUMERIC_ACCUMULATE_H
+
+#include <__config>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _Tp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_Tp
+accumulate(_InputIterator __first, _InputIterator __last, _Tp __init)
+{
+    for (; __first != __last; ++__first)
+#if _LIBCPP_STD_VER > 17
+        __init = _VSTD::move(__init) + *__first;
+#else
+        __init = __init + *__first;
+#endif
+    return __init;
+}
+
+template <class _InputIterator, class _Tp, class _BinaryOperation>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_Tp
+accumulate(_InputIterator __first, _InputIterator __last, _Tp __init, _BinaryOperation __binary_op)
+{
+    for (; __first != __last; ++__first)
+#if _LIBCPP_STD_VER > 17
+        __init = __binary_op(_VSTD::move(__init), *__first);
+#else
+        __init = __binary_op(__init, *__first);
+#endif
+    return __init;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_ACCUMULATE_H
\ No newline at end of file
diff --git a/libcxx/include/__numeric/adjacent_difference.h b/libcxx/include/__numeric/adjacent_difference.h
new file mode 100644
--- /dev/null
+++ b/libcxx/include/__numeric/adjacent_difference.h
@@ -0,0 +1,72 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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 _LIBCPP___NUMERIC_ADJACENT_DIFFERENCE_H
+#define _LIBCPP___NUMERIC_ADJACENT_DIFFERENCE_H
+
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _OutputIterator>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+adjacent_difference(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
+{
+    if (__first != __last)
+    {
+        typename iterator_traits<_InputIterator>::value_type __acc(*__first);
+        *__result = __acc;
+        for (++__first, (void) ++__result; __first != __last; ++__first, (void) ++__result)
+        {
+            typename iterator_traits<_InputIterator>::value_type __val(*__first);
+#if _LIBCPP_STD_VER > 17
+            *__result = __val - _VSTD::move(__acc);
+#else
+            *__result = __val - __acc;
+#endif
+            __acc = _VSTD::move(__val);
+        }
+    }
+    return __result;
+}
+
+template <class _InputIterator, class _OutputIterator, class _BinaryOperation>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+adjacent_difference(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
+                      _BinaryOperation __binary_op)
+{
+    if (__first != __last)
+    {
+        typename iterator_traits<_InputIterator>::value_type __acc(*__first);
+        *__result = __acc;
+        for (++__first, (void) ++__result; __first != __last; ++__first, (void) ++__result)
+        {
+            typename iterator_traits<_InputIterator>::value_type __val(*__first);
+#if _LIBCPP_STD_VER > 17
+            *__result = __binary_op(__val, _VSTD::move(__acc));
+#else
+            *__result = __binary_op(__val, __acc);
+#endif
+            __acc = _VSTD::move(__val);
+        }
+    }
+    return __result;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_ADJACENT_DIFFERENCE_H
diff --git a/libcxx/include/__numeric/exclusive_scan.h b/libcxx/include/__numeric/exclusive_scan.h
new file mode 100644
--- /dev/null
+++ b/libcxx/include/__numeric/exclusive_scan.h
@@ -0,0 +1,53 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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 _LIBCPP___NUMERIC_EXCLUSIVE_SCAN_H
+#define _LIBCPP___NUMERIC_EXCLUSIVE_SCAN_H
+
+#include <__config>
+#include <__functional/operations.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER > 14
+
+template <class _InputIterator, class _OutputIterator, class _Tp, class _BinaryOp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
+exclusive_scan(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _Tp __init, _BinaryOp __b) {
+  if (__first != __last) {
+    _Tp __tmp(__b(__init, *__first));
+    while (true) {
+      *__result = _VSTD::move(__init);
+      ++__result;
+      ++__first;
+      if (__first == __last)
+        break;
+      __init = _VSTD::move(__tmp);
+      __tmp = __b(__init, *__first);
+    }
+  }
+  return __result;
+}
+
+template <class _InputIterator, class _OutputIterator, class _Tp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
+exclusive_scan(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _Tp __init) {
+  return _VSTD::exclusive_scan(__first, __last, __result, __init, _VSTD::plus<>());
+}
+
+#endif // _LIBCPP_STD_VER > 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_EXCLUSIVE_SCAN_H
diff --git a/libcxx/include/__numeric/gcd_lcm.h b/libcxx/include/__numeric/gcd_lcm.h
new file mode 100644
--- /dev/null
+++ b/libcxx/include/__numeric/gcd_lcm.h
@@ -0,0 +1,96 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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 _LIBCPP___NUMERIC_GCD_LCM_H
+#define _LIBCPP___NUMERIC_GCD_LCM_H
+
+#include <__config>
+#include <__debug>
+#include <limits>
+#include <type_traits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER > 14
+
+template <typename _Result, typename _Source, bool _IsSigned = is_signed<_Source>::value> struct __ct_abs;
+
+template <typename _Result, typename _Source>
+struct __ct_abs<_Result, _Source, true> {
+    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
+    _Result operator()(_Source __t) const noexcept
+    {
+        if (__t >= 0) return __t;
+        if (__t == numeric_limits<_Source>::min()) return -static_cast<_Result>(__t);
+        return -__t;
+    }
+};
+
+template <typename _Result, typename _Source>
+struct __ct_abs<_Result, _Source, false> {
+    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
+    _Result operator()(_Source __t) const noexcept { return __t; }
+};
+
+
+template<class _Tp>
+_LIBCPP_CONSTEXPR _LIBCPP_HIDDEN
+_Tp __gcd(_Tp __m, _Tp __n)
+{
+    static_assert((!is_signed<_Tp>::value), "");
+    return __n == 0 ? __m : _VSTD::__gcd<_Tp>(__n, __m % __n);
+}
+
+template<class _Tp, class _Up>
+_LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
+common_type_t<_Tp,_Up>
+gcd(_Tp __m, _Up __n)
+{
+    static_assert((is_integral<_Tp>::value && is_integral<_Up>::value), "Arguments to gcd must be integer types");
+    static_assert((!is_same<typename remove_cv<_Tp>::type, bool>::value), "First argument to gcd cannot be bool" );
+    static_assert((!is_same<typename remove_cv<_Up>::type, bool>::value), "Second argument to gcd cannot be bool" );
+    using _Rp = common_type_t<_Tp,_Up>;
+    using _Wp = make_unsigned_t<_Rp>;
+    return static_cast<_Rp>(_VSTD::__gcd(
+        static_cast<_Wp>(__ct_abs<_Rp, _Tp>()(__m)),
+        static_cast<_Wp>(__ct_abs<_Rp, _Up>()(__n))));
+}
+
+template<class _Tp, class _Up>
+_LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
+common_type_t<_Tp,_Up>
+lcm(_Tp __m, _Up __n)
+{
+    static_assert((is_integral<_Tp>::value && is_integral<_Up>::value), "Arguments to lcm must be integer types");
+    static_assert((!is_same<typename remove_cv<_Tp>::type, bool>::value), "First argument to lcm cannot be bool" );
+    static_assert((!is_same<typename remove_cv<_Up>::type, bool>::value), "Second argument to lcm cannot be bool" );
+    if (__m == 0 || __n == 0)
+        return 0;
+
+    using _Rp = common_type_t<_Tp,_Up>;
+    _Rp __val1 = __ct_abs<_Rp, _Tp>()(__m) / _VSTD::gcd(__m, __n);
+    _Rp __val2 = __ct_abs<_Rp, _Up>()(__n);
+    _LIBCPP_ASSERT((numeric_limits<_Rp>::max() / __val1 > __val2), "Overflow in lcm");
+    return __val1 * __val2;
+}
+
+#endif // _LIBCPP_STD_VER
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___NUMERIC_GCD_LCM_H
diff --git a/libcxx/include/__numeric/inclusive_scan.h b/libcxx/include/__numeric/inclusive_scan.h
new file mode 100644
--- /dev/null
+++ b/libcxx/include/__numeric/inclusive_scan.h
@@ -0,0 +1,60 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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 _LIBCPP___NUMERIC_INCLUSIVE_SCAN_H
+#define _LIBCPP___NUMERIC_INCLUSIVE_SCAN_H
+
+#include <__config>
+#include <__functional/operations.h>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER > 14
+
+template <class _InputIterator, class _OutputIterator, class _Tp, class _BinaryOp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
+inclusive_scan(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryOp __b, _Tp __init) {
+  for (; __first != __last; ++__first, (void)++__result) {
+    __init = __b(__init, *__first);
+    *__result = __init;
+  }
+  return __result;
+}
+
+template <class _InputIterator, class _OutputIterator, class _BinaryOp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
+inclusive_scan(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryOp __b) {
+  if (__first != __last) {
+    typename iterator_traits<_InputIterator>::value_type __init = *__first;
+    *__result++ = __init;
+    if (++__first != __last)
+      return _VSTD::inclusive_scan(__first, __last, __result, __b, __init);
+  }
+
+  return __result;
+}
+
+template <class _InputIterator, class _OutputIterator>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator inclusive_scan(_InputIterator __first,
+                                                                                       _InputIterator __last,
+                                                                                       _OutputIterator __result) {
+  return _VSTD::inclusive_scan(__first, __last, __result, _VSTD::plus<>());
+}
+
+#endif // _LIBCPP_STD_VER > 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_INCLUSIVE_SCAN_H
diff --git a/libcxx/include/__numeric/inner_product.h b/libcxx/include/__numeric/inner_product.h
new file mode 100644
--- /dev/null
+++ b/libcxx/include/__numeric/inner_product.h
@@ -0,0 +1,53 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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 _LIBCPP___NUMERIC_INNER_PRODUCT_H
+#define _LIBCPP___NUMERIC_INNER_PRODUCT_H
+
+#include <__config>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator1, class _InputIterator2, class _Tp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_Tp
+inner_product(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _Tp __init)
+{
+    for (; __first1 != __last1; ++__first1, (void) ++__first2)
+#if _LIBCPP_STD_VER > 17
+        __init = _VSTD::move(__init) + *__first1 * *__first2;
+#else
+        __init = __init + *__first1 * *__first2;
+#endif
+    return __init;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _Tp, class _BinaryOperation1, class _BinaryOperation2>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_Tp
+inner_product(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2,
+              _Tp __init, _BinaryOperation1 __binary_op1, _BinaryOperation2 __binary_op2)
+{
+    for (; __first1 != __last1; ++__first1, (void) ++__first2)
+#if _LIBCPP_STD_VER > 17
+        __init = __binary_op1(_VSTD::move(__init), __binary_op2(*__first1, *__first2));
+#else
+        __init = __binary_op1(__init, __binary_op2(*__first1, *__first2));
+#endif
+    return __init;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_INNER_PRODUCT_H
diff --git a/libcxx/include/__numeric/iota.h b/libcxx/include/__numeric/iota.h
new file mode 100644
--- /dev/null
+++ b/libcxx/include/__numeric/iota.h
@@ -0,0 +1,32 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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 _LIBCPP___NUMERIC_IOTA_H
+#define _LIBCPP___NUMERIC_IOTA_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ForwardIterator, class _Tp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+iota(_ForwardIterator __first, _ForwardIterator __last, _Tp __value_)
+{
+    for (; __first != __last; ++__first, (void) ++__value_)
+        *__first = __value_;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_IOTA_H
diff --git a/libcxx/include/__numeric/midpoint.h b/libcxx/include/__numeric/midpoint.h
new file mode 100644
--- /dev/null
+++ b/libcxx/include/__numeric/midpoint.h
@@ -0,0 +1,85 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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 _LIBCPP___NUMERIC_MIDPOINT_H
+#define _LIBCPP___NUMERIC_MIDPOINT_H
+
+#include <__config>
+#include <limits>
+#include <type_traits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER > 17
+template <class _Tp>
+_LIBCPP_INLINE_VISIBILITY constexpr
+enable_if_t<is_integral_v<_Tp> && !is_same_v<bool, _Tp> && !is_null_pointer_v<_Tp>, _Tp>
+midpoint(_Tp __a, _Tp __b) noexcept
+_LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
+{
+    using _Up = make_unsigned_t<_Tp>;
+    constexpr _Up __bitshift = numeric_limits<_Up>::digits - 1;
+
+    _Up __diff = _Up(__b) - _Up(__a);
+    _Up __sign_bit = __b < __a;
+
+    _Up __half_diff = (__diff / 2) + (__sign_bit << __bitshift) + (__sign_bit & __diff);
+
+    return __a + __half_diff;
+}
+
+
+template <class _TPtr>
+_LIBCPP_INLINE_VISIBILITY constexpr
+enable_if_t<is_pointer_v<_TPtr>
+             && is_object_v<remove_pointer_t<_TPtr>>
+             && ! is_void_v<remove_pointer_t<_TPtr>>
+             && (sizeof(remove_pointer_t<_TPtr>) > 0), _TPtr>
+midpoint(_TPtr __a, _TPtr __b) noexcept
+{
+    return __a + _VSTD::midpoint(ptrdiff_t(0), __b - __a);
+}
+
+
+template <typename _Tp>
+constexpr int __sign(_Tp __val) {
+    return (_Tp(0) < __val) - (__val < _Tp(0));
+}
+
+template <typename _Fp>
+constexpr _Fp __fp_abs(_Fp __f) { return __f >= 0 ? __f : -__f; }
+
+template <class _Fp>
+_LIBCPP_INLINE_VISIBILITY constexpr
+enable_if_t<is_floating_point_v<_Fp>, _Fp>
+midpoint(_Fp __a, _Fp __b) noexcept
+{
+    constexpr _Fp __lo = numeric_limits<_Fp>::min()*2;
+    constexpr _Fp __hi = numeric_limits<_Fp>::max()/2;
+    return __fp_abs(__a) <= __hi && __fp_abs(__b) <= __hi ?  // typical case: overflow is impossible
+      (__a + __b)/2 :                                        // always correctly rounded
+      __fp_abs(__a) < __lo ? __a + __b/2 :                   // not safe to halve a
+      __fp_abs(__b) < __lo ? __a/2 + __b :                   // not safe to halve b
+      __a/2 + __b/2;                                         // otherwise correctly rounded
+}
+
+#endif // _LIBCPP_STD_VER > 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___NUMERIC_MIDPOINT_H
diff --git a/libcxx/include/__numeric/partial_sum.h b/libcxx/include/__numeric/partial_sum.h
new file mode 100644
--- /dev/null
+++ b/libcxx/include/__numeric/partial_sum.h
@@ -0,0 +1,70 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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 _LIBCPP___NUMERIC_PARTIAL_SUM_H
+#define _LIBCPP___NUMERIC_PARTIAL_SUM_H
+
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIterator, class _OutputIterator>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+partial_sum(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
+{
+    if (__first != __last)
+    {
+        typename iterator_traits<_InputIterator>::value_type __t(*__first);
+        *__result = __t;
+        for (++__first, (void) ++__result; __first != __last; ++__first, (void) ++__result)
+        {
+#if _LIBCPP_STD_VER > 17
+            __t = _VSTD::move(__t) + *__first;
+#else
+            __t = __t + *__first;
+#endif
+            *__result = __t;
+        }
+    }
+    return __result;
+}
+
+template <class _InputIterator, class _OutputIterator, class _BinaryOperation>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+partial_sum(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
+              _BinaryOperation __binary_op)
+{
+    if (__first != __last)
+    {
+        typename iterator_traits<_InputIterator>::value_type __t(*__first);
+        *__result = __t;
+        for (++__first, (void) ++__result; __first != __last; ++__first, (void) ++__result)
+        {
+#if _LIBCPP_STD_VER > 17
+            __t = __binary_op(_VSTD::move(__t), *__first);
+#else
+            __t = __binary_op(__t, *__first);
+#endif
+            *__result = __t;
+        }
+    }
+    return __result;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_PARTIAL_SUM_H
diff --git a/libcxx/include/__numeric/reduce.h b/libcxx/include/__numeric/reduce.h
new file mode 100644
--- /dev/null
+++ b/libcxx/include/__numeric/reduce.h
@@ -0,0 +1,47 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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 _LIBCPP___NUMERIC_REDUCE_H
+#define _LIBCPP___NUMERIC_REDUCE_H
+
+#include <__config>
+#include <__functional/operations.h>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER > 14
+template <class _InputIterator, class _Tp, class _BinaryOp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _Tp reduce(_InputIterator __first, _InputIterator __last,
+                                                                   _Tp __init, _BinaryOp __b) {
+  for (; __first != __last; ++__first)
+    __init = __b(__init, *__first);
+  return __init;
+}
+
+template <class _InputIterator, class _Tp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _Tp reduce(_InputIterator __first, _InputIterator __last,
+                                                                   _Tp __init) {
+  return _VSTD::reduce(__first, __last, __init, _VSTD::plus<>());
+}
+
+template <class _InputIterator>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 typename iterator_traits<_InputIterator>::value_type
+reduce(_InputIterator __first, _InputIterator __last) {
+  return _VSTD::reduce(__first, __last, typename iterator_traits<_InputIterator>::value_type{});
+}
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_REDUCE_H
diff --git a/libcxx/include/__numeric/transform_exclusive_scan.h b/libcxx/include/__numeric/transform_exclusive_scan.h
new file mode 100644
--- /dev/null
+++ b/libcxx/include/__numeric/transform_exclusive_scan.h
@@ -0,0 +1,49 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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 _LIBCPP___NUMERIC_TRANSFORM_EXCLUSIVE_SCAN_H
+#define _LIBCPP___NUMERIC_TRANSFORM_EXCLUSIVE_SCAN_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER > 14
+
+template <class _InputIterator, class _OutputIterator, class _Tp,
+          class _BinaryOp, class _UnaryOp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+transform_exclusive_scan(_InputIterator __first, _InputIterator __last,
+                           _OutputIterator __result, _Tp __init,
+                           _BinaryOp __b, _UnaryOp __u)
+{
+    if (__first != __last)
+    {
+        _Tp __saved = __init;
+        do
+        {
+            __init = __b(__init, __u(*__first));
+            *__result = __saved;
+            __saved = __init;
+            ++__result;
+        } while (++__first != __last);
+    }
+    return __result;
+}
+
+#endif // _LIBCPP_STD_VER > 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_TRANSFORM_EXCLUSIVE_SCAN_H
diff --git a/libcxx/include/__numeric/transform_inclusive_scan.h b/libcxx/include/__numeric/transform_inclusive_scan.h
new file mode 100644
--- /dev/null
+++ b/libcxx/include/__numeric/transform_inclusive_scan.h
@@ -0,0 +1,58 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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 _LIBCPP___NUMERIC_TRANSFORM_INCLUSIVE_SCAN_H
+#define _LIBCPP___NUMERIC_TRANSFORM_INCLUSIVE_SCAN_H
+
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER > 14
+
+template <class _InputIterator, class _OutputIterator, class _Tp, class _BinaryOp, class _UnaryOp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+transform_inclusive_scan(_InputIterator __first, _InputIterator __last,
+                           _OutputIterator __result, _BinaryOp __b, _UnaryOp __u, _Tp __init)
+{
+    for (; __first != __last; ++__first, (void) ++__result) {
+        __init = __b(__init, __u(*__first));
+        *__result = __init;
+        }
+
+    return __result;
+}
+
+template <class _InputIterator, class _OutputIterator, class _BinaryOp, class _UnaryOp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+transform_inclusive_scan(_InputIterator __first, _InputIterator __last,
+                               _OutputIterator __result, _BinaryOp __b, _UnaryOp __u)
+{
+    if (__first != __last) {
+        typename iterator_traits<_InputIterator>::value_type __init = __u(*__first);
+        *__result++ = __init;
+        if (++__first != __last)
+            return _VSTD::transform_inclusive_scan(__first, __last, __result, __b, __u, __init);
+    }
+
+    return __result;
+}
+
+#endif // _LIBCPP_STD_VER > 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_TRANSFORM_INCLUSIVE_SCAN_H
diff --git a/libcxx/include/__numeric/transform_reduce.h b/libcxx/include/__numeric/transform_reduce.h
new file mode 100644
--- /dev/null
+++ b/libcxx/include/__numeric/transform_reduce.h
@@ -0,0 +1,54 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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 _LIBCPP___NUMERIC_TRANSFORM_REDUCE_H
+#define _LIBCPP___NUMERIC_TRANSFORM_REDUCE_H
+
+#include <__config>
+#include <__functional/operations.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER > 14
+template <class _InputIterator, class _Tp, class _BinaryOp, class _UnaryOp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _Tp transform_reduce(_InputIterator __first,
+                                                                             _InputIterator __last, _Tp __init,
+                                                                             _BinaryOp __b, _UnaryOp __u) {
+  for (; __first != __last; ++__first)
+    __init = __b(__init, __u(*__first));
+  return __init;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _Tp, class _BinaryOp1, class _BinaryOp2>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _Tp transform_reduce(_InputIterator1 __first1,
+                                                                             _InputIterator1 __last1,
+                                                                             _InputIterator2 __first2, _Tp __init,
+                                                                             _BinaryOp1 __b1, _BinaryOp2 __b2) {
+  for (; __first1 != __last1; ++__first1, (void)++__first2)
+    __init = __b1(__init, __b2(*__first1, *__first2));
+  return __init;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _Tp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _Tp transform_reduce(_InputIterator1 __first1,
+                                                                             _InputIterator1 __last1,
+                                                                             _InputIterator2 __first2, _Tp __init) {
+  return _VSTD::transform_reduce(__first1, __last1, __first2, _VSTD::move(__init), _VSTD::plus<>(),
+                                 _VSTD::multiplies<>());
+}
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___NUMERIC_TRANSFORM_REDUCE_H
diff --git a/libcxx/include/module.modulemap b/libcxx/include/module.modulemap
--- a/libcxx/include/module.modulemap
+++ b/libcxx/include/module.modulemap
@@ -662,6 +662,22 @@
   module numeric {
     header "numeric"
     export *
+
+    module __numeric {
+      module accumulate               { private header "__numeric/accumulate.h" }
+      module adjacent_difference      { private header "__numeric/adjacent_difference.h" }
+      module exclusive_scan           { private header "__numeric/exclusive_scan.h" }
+      module gcd_lcm                  { private header "__numeric/gcd_lcm.h" }
+      module inclusive_scan           { private header "__numeric/inclusive_scan.h" }
+      module inner_product            { private header "__numeric/inner_product.h" }
+      module iota                     { private header "__numeric/iota.h" }
+      module midpoint                 { private header "__numeric/midpoint.h" }
+      module partial_sum              { private header "__numeric/partial_sum.h" }
+      module reduce                   { private header "__numeric/reduce.h" }
+      module transform_exclusive_scan { private header "__numeric/transform_exclusive_scan.h" }
+      module transform_inclusive_scan { private header "__numeric/transform_inclusive_scan.h" }
+      module transform_reduce         { private header "__numeric/transform_reduce.h" }
+    }
   }
   module optional {
     header "optional"
diff --git a/libcxx/include/numeric b/libcxx/include/numeric
--- a/libcxx/include/numeric
+++ b/libcxx/include/numeric
@@ -145,490 +145,29 @@
 */
 
 #include <__config>
-#include <__debug>
 #include <cmath> // for isnormal
 #include <functional>
 #include <iterator>
-#include <limits> // for numeric_limits
 #include <version>
 
+#include <__numeric/accumulate.h>
+#include <__numeric/adjacent_difference.h>
+#include <__numeric/exclusive_scan.h>
+#include <__numeric/gcd_lcm.h>
+#include <__numeric/inclusive_scan.h>
+#include <__numeric/inner_product.h>
+#include <__numeric/iota.h>
+#include <__numeric/midpoint.h>
+#include <__numeric/partial_sum.h>
+#include <__numeric/reduce.h>
+#include <__numeric/transform_exclusive_scan.h>
+#include <__numeric/transform_inclusive_scan.h>
+#include <__numeric/transform_reduce.h>
+
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif
 
-_LIBCPP_PUSH_MACROS
-#include <__undef_macros>
-
-_LIBCPP_BEGIN_NAMESPACE_STD
-
-template <class _InputIterator, class _Tp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_Tp
-accumulate(_InputIterator __first, _InputIterator __last, _Tp __init)
-{
-    for (; __first != __last; ++__first)
-#if _LIBCPP_STD_VER > 17
-        __init = _VSTD::move(__init) + *__first;
-#else
-        __init = __init + *__first;
-#endif
-    return __init;
-}
-
-template <class _InputIterator, class _Tp, class _BinaryOperation>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_Tp
-accumulate(_InputIterator __first, _InputIterator __last, _Tp __init, _BinaryOperation __binary_op)
-{
-    for (; __first != __last; ++__first)
-#if _LIBCPP_STD_VER > 17
-        __init = __binary_op(_VSTD::move(__init), *__first);
-#else
-        __init = __binary_op(__init, *__first);
-#endif
-    return __init;
-}
-
-#if _LIBCPP_STD_VER > 14
-template <class _InputIterator, class _Tp, class _BinaryOp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_Tp
-reduce(_InputIterator __first, _InputIterator __last, _Tp __init, _BinaryOp __b)
-{
-    for (; __first != __last; ++__first)
-        __init = __b(__init, *__first);
-    return __init;
-}
-
-template <class _InputIterator, class _Tp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_Tp
-reduce(_InputIterator __first, _InputIterator __last, _Tp __init)
-{
-    return _VSTD::reduce(__first, __last, __init, _VSTD::plus<>());
-}
-
-template <class _InputIterator>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-typename iterator_traits<_InputIterator>::value_type
-reduce(_InputIterator __first, _InputIterator __last)
-{
-    return _VSTD::reduce(__first, __last,
-       typename iterator_traits<_InputIterator>::value_type{});
-}
-#endif
-
-template <class _InputIterator1, class _InputIterator2, class _Tp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_Tp
-inner_product(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _Tp __init)
-{
-    for (; __first1 != __last1; ++__first1, (void) ++__first2)
-#if _LIBCPP_STD_VER > 17
-        __init = _VSTD::move(__init) + *__first1 * *__first2;
-#else
-        __init = __init + *__first1 * *__first2;
-#endif
-    return __init;
-}
-
-template <class _InputIterator1, class _InputIterator2, class _Tp, class _BinaryOperation1, class _BinaryOperation2>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_Tp
-inner_product(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2,
-              _Tp __init, _BinaryOperation1 __binary_op1, _BinaryOperation2 __binary_op2)
-{
-    for (; __first1 != __last1; ++__first1, (void) ++__first2)
-#if _LIBCPP_STD_VER > 17
-        __init = __binary_op1(_VSTD::move(__init), __binary_op2(*__first1, *__first2));
-#else
-        __init = __binary_op1(__init, __binary_op2(*__first1, *__first2));
-#endif
-    return __init;
-}
-
-#if _LIBCPP_STD_VER > 14
-template <class _InputIterator, class _Tp, class _BinaryOp, class _UnaryOp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_Tp
-transform_reduce(_InputIterator __first, _InputIterator __last,
-           _Tp __init,  _BinaryOp __b, _UnaryOp __u)
-{
-    for (; __first != __last; ++__first)
-        __init = __b(__init, __u(*__first));
-    return __init;
-}
-
-template <class _InputIterator1, class _InputIterator2,
-          class _Tp, class _BinaryOp1, class _BinaryOp2>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_Tp
-transform_reduce(_InputIterator1 __first1, _InputIterator1 __last1,
-                 _InputIterator2 __first2, _Tp __init,  _BinaryOp1 __b1, _BinaryOp2 __b2)
-{
-    for (; __first1 != __last1; ++__first1, (void) ++__first2)
-        __init = __b1(__init, __b2(*__first1, *__first2));
-    return __init;
-}
-
-template <class _InputIterator1, class _InputIterator2, class _Tp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_Tp
-transform_reduce(_InputIterator1 __first1, _InputIterator1 __last1,
-                 _InputIterator2 __first2, _Tp __init)
-{
-    return _VSTD::transform_reduce(__first1, __last1, __first2, _VSTD::move(__init),
-                                   _VSTD::plus<>(), _VSTD::multiplies<>());
-}
-#endif
-
-template <class _InputIterator, class _OutputIterator>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_OutputIterator
-partial_sum(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
-{
-    if (__first != __last)
-    {
-        typename iterator_traits<_InputIterator>::value_type __t(*__first);
-        *__result = __t;
-        for (++__first, (void) ++__result; __first != __last; ++__first, (void) ++__result)
-        {
-#if _LIBCPP_STD_VER > 17
-            __t = _VSTD::move(__t) + *__first;
-#else
-            __t = __t + *__first;
-#endif
-            *__result = __t;
-        }
-    }
-    return __result;
-}
-
-template <class _InputIterator, class _OutputIterator, class _BinaryOperation>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_OutputIterator
-partial_sum(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
-              _BinaryOperation __binary_op)
-{
-    if (__first != __last)
-    {
-        typename iterator_traits<_InputIterator>::value_type __t(*__first);
-        *__result = __t;
-        for (++__first, (void) ++__result; __first != __last; ++__first, (void) ++__result)
-        {
-#if _LIBCPP_STD_VER > 17
-            __t = __binary_op(_VSTD::move(__t), *__first);
-#else
-            __t = __binary_op(__t, *__first);
-#endif
-            *__result = __t;
-        }
-    }
-    return __result;
-}
-
-#if _LIBCPP_STD_VER > 14
-template <class _InputIterator, class _OutputIterator, class _Tp, class _BinaryOp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_OutputIterator
-exclusive_scan(_InputIterator __first, _InputIterator __last,
-               _OutputIterator __result, _Tp __init, _BinaryOp __b)
-{
-    if (__first != __last)
-    {
-        _Tp __tmp(__b(__init, *__first));
-        while (true)
-        {
-            *__result = _VSTD::move(__init);
-            ++__result;
-            ++__first;
-            if (__first == __last)
-                break;
-            __init = _VSTD::move(__tmp);
-            __tmp = __b(__init, *__first);
-        }
-    }
-    return __result;
-}
-
-template <class _InputIterator, class _OutputIterator, class _Tp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_OutputIterator
-exclusive_scan(_InputIterator __first, _InputIterator __last,
-               _OutputIterator __result, _Tp __init)
-{
-    return _VSTD::exclusive_scan(__first, __last, __result, __init, _VSTD::plus<>());
-}
-
-template <class _InputIterator, class _OutputIterator, class _Tp, class _BinaryOp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_OutputIterator inclusive_scan(_InputIterator __first, _InputIterator __last,
-                               _OutputIterator __result, _BinaryOp __b,  _Tp __init)
-{
-    for (; __first != __last; ++__first, (void) ++__result) {
-        __init = __b(__init, *__first);
-        *__result = __init;
-    }
-    return __result;
-}
-
-template <class _InputIterator, class _OutputIterator, class _BinaryOp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_OutputIterator inclusive_scan(_InputIterator __first, _InputIterator __last,
-                               _OutputIterator __result, _BinaryOp __b)
-{
-    if (__first != __last) {
-        typename iterator_traits<_InputIterator>::value_type __init = *__first;
-        *__result++ = __init;
-        if (++__first != __last)
-            return _VSTD::inclusive_scan(__first, __last, __result, __b, __init);
-    }
-
-    return __result;
-}
-
-template <class _InputIterator, class _OutputIterator>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_OutputIterator inclusive_scan(_InputIterator __first, _InputIterator __last,
-                               _OutputIterator __result)
-{
-    return _VSTD::inclusive_scan(__first, __last, __result, _VSTD::plus<>());
-}
-
-template <class _InputIterator, class _OutputIterator, class _Tp,
-          class _BinaryOp, class _UnaryOp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_OutputIterator
-transform_exclusive_scan(_InputIterator __first, _InputIterator __last,
-                           _OutputIterator __result, _Tp __init,
-                           _BinaryOp __b, _UnaryOp __u)
-{
-    if (__first != __last)
-    {
-        _Tp __saved = __init;
-        do
-        {
-            __init = __b(__init, __u(*__first));
-            *__result = __saved;
-            __saved = __init;
-            ++__result;
-        } while (++__first != __last);
-    }
-    return __result;
-}
-
-template <class _InputIterator, class _OutputIterator, class _Tp, class _BinaryOp, class _UnaryOp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_OutputIterator
-transform_inclusive_scan(_InputIterator __first, _InputIterator __last,
-                           _OutputIterator __result, _BinaryOp __b, _UnaryOp __u, _Tp __init)
-{
-    for (; __first != __last; ++__first, (void) ++__result) {
-        __init = __b(__init, __u(*__first));
-        *__result = __init;
-        }
-
-    return __result;
-}
-
-template <class _InputIterator, class _OutputIterator, class _BinaryOp, class _UnaryOp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_OutputIterator
-transform_inclusive_scan(_InputIterator __first, _InputIterator __last,
-                               _OutputIterator __result, _BinaryOp __b, _UnaryOp __u)
-{
-    if (__first != __last) {
-        typename iterator_traits<_InputIterator>::value_type __init = __u(*__first);
-        *__result++ = __init;
-        if (++__first != __last)
-            return _VSTD::transform_inclusive_scan(__first, __last, __result, __b, __u, __init);
-    }
-
-    return __result;
-}
-#endif
-
-template <class _InputIterator, class _OutputIterator>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_OutputIterator
-adjacent_difference(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
-{
-    if (__first != __last)
-    {
-        typename iterator_traits<_InputIterator>::value_type __acc(*__first);
-        *__result = __acc;
-        for (++__first, (void) ++__result; __first != __last; ++__first, (void) ++__result)
-        {
-            typename iterator_traits<_InputIterator>::value_type __val(*__first);
-#if _LIBCPP_STD_VER > 17
-            *__result = __val - _VSTD::move(__acc);
-#else
-            *__result = __val - __acc;
-#endif
-            __acc = _VSTD::move(__val);
-        }
-    }
-    return __result;
-}
-
-template <class _InputIterator, class _OutputIterator, class _BinaryOperation>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-_OutputIterator
-adjacent_difference(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
-                      _BinaryOperation __binary_op)
-{
-    if (__first != __last)
-    {
-        typename iterator_traits<_InputIterator>::value_type __acc(*__first);
-        *__result = __acc;
-        for (++__first, (void) ++__result; __first != __last; ++__first, (void) ++__result)
-        {
-            typename iterator_traits<_InputIterator>::value_type __val(*__first);
-#if _LIBCPP_STD_VER > 17
-            *__result = __binary_op(__val, _VSTD::move(__acc));
-#else
-            *__result = __binary_op(__val, __acc);
-#endif
-            __acc = _VSTD::move(__val);
-        }
-    }
-    return __result;
-}
-
-template <class _ForwardIterator, class _Tp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
-void
-iota(_ForwardIterator __first, _ForwardIterator __last, _Tp __value_)
-{
-    for (; __first != __last; ++__first, (void) ++__value_)
-        *__first = __value_;
-}
-
-
-#if _LIBCPP_STD_VER > 14
-template <typename _Result, typename _Source, bool _IsSigned = is_signed<_Source>::value> struct __ct_abs;
-
-template <typename _Result, typename _Source>
-struct __ct_abs<_Result, _Source, true> {
-    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
-    _Result operator()(_Source __t) const noexcept
-    {
-        if (__t >= 0) return __t;
-        if (__t == numeric_limits<_Source>::min()) return -static_cast<_Result>(__t);
-        return -__t;
-    }
-};
-
-template <typename _Result, typename _Source>
-struct __ct_abs<_Result, _Source, false> {
-    _LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
-    _Result operator()(_Source __t) const noexcept { return __t; }
-};
-
-
-template<class _Tp>
-_LIBCPP_CONSTEXPR _LIBCPP_HIDDEN
-_Tp __gcd(_Tp __m, _Tp __n)
-{
-    static_assert((!is_signed<_Tp>::value), "");
-    return __n == 0 ? __m : _VSTD::__gcd<_Tp>(__n, __m % __n);
-}
-
-
-template<class _Tp, class _Up>
-_LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
-common_type_t<_Tp,_Up>
-gcd(_Tp __m, _Up __n)
-{
-    static_assert((is_integral<_Tp>::value && is_integral<_Up>::value), "Arguments to gcd must be integer types");
-    static_assert((!is_same<typename remove_cv<_Tp>::type, bool>::value), "First argument to gcd cannot be bool" );
-    static_assert((!is_same<typename remove_cv<_Up>::type, bool>::value), "Second argument to gcd cannot be bool" );
-    using _Rp = common_type_t<_Tp,_Up>;
-    using _Wp = make_unsigned_t<_Rp>;
-    return static_cast<_Rp>(_VSTD::__gcd(
-        static_cast<_Wp>(__ct_abs<_Rp, _Tp>()(__m)),
-        static_cast<_Wp>(__ct_abs<_Rp, _Up>()(__n))));
-}
-
-template<class _Tp, class _Up>
-_LIBCPP_CONSTEXPR _LIBCPP_INLINE_VISIBILITY
-common_type_t<_Tp,_Up>
-lcm(_Tp __m, _Up __n)
-{
-    static_assert((is_integral<_Tp>::value && is_integral<_Up>::value), "Arguments to lcm must be integer types");
-    static_assert((!is_same<typename remove_cv<_Tp>::type, bool>::value), "First argument to lcm cannot be bool" );
-    static_assert((!is_same<typename remove_cv<_Up>::type, bool>::value), "Second argument to lcm cannot be bool" );
-    if (__m == 0 || __n == 0)
-        return 0;
-
-    using _Rp = common_type_t<_Tp,_Up>;
-    _Rp __val1 = __ct_abs<_Rp, _Tp>()(__m) / _VSTD::gcd(__m, __n);
-    _Rp __val2 = __ct_abs<_Rp, _Up>()(__n);
-    _LIBCPP_ASSERT((numeric_limits<_Rp>::max() / __val1 > __val2), "Overflow in lcm");
-    return __val1 * __val2;
-}
-
-#endif /* _LIBCPP_STD_VER > 14 */
-
-#if _LIBCPP_STD_VER > 17
-template <class _Tp>
-_LIBCPP_INLINE_VISIBILITY constexpr
-enable_if_t<is_integral_v<_Tp> && !is_same_v<bool, _Tp> && !is_null_pointer_v<_Tp>, _Tp>
-midpoint(_Tp __a, _Tp __b) noexcept
-_LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
-{
-    using _Up = make_unsigned_t<_Tp>;
-    constexpr _Up __bitshift = numeric_limits<_Up>::digits - 1;
-
-    _Up __diff = _Up(__b) - _Up(__a);
-    _Up __sign_bit = __b < __a;
-
-    _Up __half_diff = (__diff / 2) + (__sign_bit << __bitshift) + (__sign_bit & __diff);
-
-    return __a + __half_diff;
-}
-
-
-template <class _TPtr>
-_LIBCPP_INLINE_VISIBILITY constexpr
-enable_if_t<is_pointer_v<_TPtr>
-             && is_object_v<remove_pointer_t<_TPtr>>
-             && ! is_void_v<remove_pointer_t<_TPtr>>
-             && (sizeof(remove_pointer_t<_TPtr>) > 0), _TPtr>
-midpoint(_TPtr __a, _TPtr __b) noexcept
-{
-    return __a + _VSTD::midpoint(ptrdiff_t(0), __b - __a);
-}
-
-
-template <typename _Tp>
-constexpr int __sign(_Tp __val) {
-    return (_Tp(0) < __val) - (__val < _Tp(0));
-}
-
-template <typename _Fp>
-constexpr _Fp __fp_abs(_Fp __f) { return __f >= 0 ? __f : -__f; }
-
-template <class _Fp>
-_LIBCPP_INLINE_VISIBILITY constexpr
-enable_if_t<is_floating_point_v<_Fp>, _Fp>
-midpoint(_Fp __a, _Fp __b) noexcept
-{
-    constexpr _Fp __lo = numeric_limits<_Fp>::min()*2;
-    constexpr _Fp __hi = numeric_limits<_Fp>::max()/2;
-    return __fp_abs(__a) <= __hi && __fp_abs(__b) <= __hi ?  // typical case: overflow is impossible
-      (__a + __b)/2 :                                        // always correctly rounded
-      __fp_abs(__a) < __lo ? __a + __b/2 :                   // not safe to halve a
-      __fp_abs(__b) < __lo ? __a/2 + __b :                   // not safe to halve b
-      __a/2 + __b/2;                                         // otherwise correctly rounded
-}
-
-#endif // _LIBCPP_STD_VER > 17
-
-_LIBCPP_END_NAMESPACE_STD
-
-_LIBCPP_POP_MACROS
-
 #if defined(_LIBCPP_HAS_PARALLEL_ALGORITHMS) && _LIBCPP_STD_VER >= 17
 #   include <__pstl_numeric>
 #endif