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diff --git a/contrib/llvm-project/libcxx/include/__random/piecewise_linear_distribution.h b/contrib/llvm-project/libcxx/include/__random/piecewise_linear_distribution.h
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index 000000000000..43769dc825e6
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+++ b/contrib/llvm-project/libcxx/include/__random/piecewise_linear_distribution.h
@@ -0,0 +1,315 @@
+//===----------------------------------------------------------------------===//
+//
+// 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___RANDOM_PIECEWISE_LINEAR_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_PIECEWISE_LINEAR_DISTRIBUTION_H
+
+#include <__algorithm/upper_bound.h>
+#include <__config>
+#include <__random/is_valid.h>
+#include <__random/uniform_real_distribution.h>
+#include <cmath>
+#include <iosfwd>
+#include <vector>
+
+#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 _RealType = double>
+class _LIBCPP_TEMPLATE_VIS piecewise_linear_distribution {
+  static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,
+                "RealType must be a supported floating-point type");
+
+public:
+  // types
+  typedef _RealType result_type;
+
+  class _LIBCPP_TEMPLATE_VIS param_type {
+    vector<result_type> __b_;
+    vector<result_type> __densities_;
+    vector<result_type> __areas_;
+
+  public:
+    typedef piecewise_linear_distribution distribution_type;
+
+    _LIBCPP_HIDE_FROM_ABI param_type();
+    template <class _InputIteratorB, class _InputIteratorW>
+    _LIBCPP_HIDE_FROM_ABI param_type(_InputIteratorB __f_b, _InputIteratorB __l_b, _InputIteratorW __f_w);
+#ifndef _LIBCPP_CXX03_LANG
+    template <class _UnaryOperation>
+    _LIBCPP_HIDE_FROM_ABI param_type(initializer_list<result_type> __bl, _UnaryOperation __fw);
+#endif // _LIBCPP_CXX03_LANG
+    template <class _UnaryOperation>
+    _LIBCPP_HIDE_FROM_ABI param_type(size_t __nw, result_type __xmin, result_type __xmax, _UnaryOperation __fw);
+    _LIBCPP_HIDE_FROM_ABI param_type(param_type const&) = default;
+    _LIBCPP_HIDE_FROM_ABI param_type& operator=(const param_type& __rhs);
+
+    _LIBCPP_HIDE_FROM_ABI vector<result_type> intervals() const { return __b_; }
+    _LIBCPP_HIDE_FROM_ABI vector<result_type> densities() const { return __densities_; }
+
+    friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {
+      return __x.__densities_ == __y.__densities_ && __x.__b_ == __y.__b_;
+    }
+    friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+
+  private:
+    _LIBCPP_HIDE_FROM_ABI void __init();
+
+    friend class piecewise_linear_distribution;
+
+    template <class _CharT, class _Traits, class _RT>
+    friend basic_ostream<_CharT, _Traits>&
+    operator<<(basic_ostream<_CharT, _Traits>& __os, const piecewise_linear_distribution<_RT>& __x);
+
+    template <class _CharT, class _Traits, class _RT>
+    friend basic_istream<_CharT, _Traits>&
+    operator>>(basic_istream<_CharT, _Traits>& __is, piecewise_linear_distribution<_RT>& __x);
+  };
+
+private:
+  param_type __p_;
+
+public:
+  // constructor and reset functions
+  _LIBCPP_HIDE_FROM_ABI piecewise_linear_distribution() {}
+  template <class _InputIteratorB, class _InputIteratorW>
+  _LIBCPP_HIDE_FROM_ABI
+  piecewise_linear_distribution(_InputIteratorB __f_b, _InputIteratorB __l_b, _InputIteratorW __f_w)
+      : __p_(__f_b, __l_b, __f_w) {}
+
+#ifndef _LIBCPP_CXX03_LANG
+  template <class _UnaryOperation>
+  _LIBCPP_HIDE_FROM_ABI piecewise_linear_distribution(initializer_list<result_type> __bl, _UnaryOperation __fw)
+      : __p_(__bl, __fw) {}
+#endif // _LIBCPP_CXX03_LANG
+
+  template <class _UnaryOperation>
+  _LIBCPP_HIDE_FROM_ABI
+  piecewise_linear_distribution(size_t __nw, result_type __xmin, result_type __xmax, _UnaryOperation __fw)
+      : __p_(__nw, __xmin, __xmax, __fw) {}
+
+  _LIBCPP_HIDE_FROM_ABI explicit piecewise_linear_distribution(const param_type& __p) : __p_(__p) {}
+
+  _LIBCPP_HIDE_FROM_ABI void reset() {}
+
+  // generating functions
+  template <class _URNG>
+  _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {
+    return (*this)(__g, __p_);
+  }
+  template <class _URNG>
+  _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);
+
+  // property functions
+  _LIBCPP_HIDE_FROM_ABI vector<result_type> intervals() const { return __p_.intervals(); }
+  _LIBCPP_HIDE_FROM_ABI vector<result_type> densities() const { return __p_.densities(); }
+
+  _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }
+  _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }
+
+  _LIBCPP_HIDE_FROM_ABI result_type min() const { return __p_.__b_.front(); }
+  _LIBCPP_HIDE_FROM_ABI result_type max() const { return __p_.__b_.back(); }
+
+  friend _LIBCPP_HIDE_FROM_ABI bool
+  operator==(const piecewise_linear_distribution& __x, const piecewise_linear_distribution& __y) {
+    return __x.__p_ == __y.__p_;
+  }
+  friend _LIBCPP_HIDE_FROM_ABI bool
+  operator!=(const piecewise_linear_distribution& __x, const piecewise_linear_distribution& __y) {
+    return !(__x == __y);
+  }
+
+  template <class _CharT, class _Traits, class _RT>
+  friend basic_ostream<_CharT, _Traits>&
+  operator<<(basic_ostream<_CharT, _Traits>& __os, const piecewise_linear_distribution<_RT>& __x);
+
+  template <class _CharT, class _Traits, class _RT>
+  friend basic_istream<_CharT, _Traits>&
+  operator>>(basic_istream<_CharT, _Traits>& __is, piecewise_linear_distribution<_RT>& __x);
+};
+
+template <class _RealType>
+typename piecewise_linear_distribution<_RealType>::param_type&
+piecewise_linear_distribution<_RealType>::param_type::operator=(const param_type& __rhs) {
+  //  These can throw
+  __b_.reserve(__rhs.__b_.size());
+  __densities_.reserve(__rhs.__densities_.size());
+  __areas_.reserve(__rhs.__areas_.size());
+
+  //  These can not throw
+  __b_         = __rhs.__b_;
+  __densities_ = __rhs.__densities_;
+  __areas_     = __rhs.__areas_;
+  return *this;
+}
+
+template <class _RealType>
+void piecewise_linear_distribution<_RealType>::param_type::__init() {
+  __areas_.assign(__densities_.size() - 1, result_type());
+  result_type __sp = 0;
+  for (size_t __i = 0; __i < __areas_.size(); ++__i) {
+    __areas_[__i] = (__densities_[__i + 1] + __densities_[__i]) * (__b_[__i + 1] - __b_[__i]) * .5;
+    __sp += __areas_[__i];
+  }
+  for (size_t __i = __areas_.size(); __i > 1;) {
+    --__i;
+    __areas_[__i] = __areas_[__i - 1] / __sp;
+  }
+  __areas_[0] = 0;
+  for (size_t __i = 1; __i < __areas_.size(); ++__i)
+    __areas_[__i] += __areas_[__i - 1];
+  for (size_t __i = 0; __i < __densities_.size(); ++__i)
+    __densities_[__i] /= __sp;
+}
+
+template <class _RealType>
+piecewise_linear_distribution<_RealType>::param_type::param_type() : __b_(2), __densities_(2, 1.0), __areas_(1, 0.0) {
+  __b_[1] = 1;
+}
+
+template <class _RealType>
+template <class _InputIteratorB, class _InputIteratorW>
+piecewise_linear_distribution<_RealType>::param_type::param_type(
+    _InputIteratorB __f_b, _InputIteratorB __l_b, _InputIteratorW __f_w)
+    : __b_(__f_b, __l_b) {
+  if (__b_.size() < 2) {
+    __b_.resize(2);
+    __b_[0] = 0;
+    __b_[1] = 1;
+    __densities_.assign(2, 1.0);
+    __areas_.assign(1, 0.0);
+  } else {
+    __densities_.reserve(__b_.size());
+    for (size_t __i = 0; __i < __b_.size(); ++__i, ++__f_w)
+      __densities_.push_back(*__f_w);
+    __init();
+  }
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template <class _RealType>
+template <class _UnaryOperation>
+piecewise_linear_distribution<_RealType>::param_type::param_type(
+    initializer_list<result_type> __bl, _UnaryOperation __fw)
+    : __b_(__bl.begin(), __bl.end()) {
+  if (__b_.size() < 2) {
+    __b_.resize(2);
+    __b_[0] = 0;
+    __b_[1] = 1;
+    __densities_.assign(2, 1.0);
+    __areas_.assign(1, 0.0);
+  } else {
+    __densities_.reserve(__b_.size());
+    for (size_t __i = 0; __i < __b_.size(); ++__i)
+      __densities_.push_back(__fw(__b_[__i]));
+    __init();
+  }
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+template <class _RealType>
+template <class _UnaryOperation>
+piecewise_linear_distribution<_RealType>::param_type::param_type(
+    size_t __nw, result_type __xmin, result_type __xmax, _UnaryOperation __fw)
+    : __b_(__nw == 0 ? 2 : __nw + 1) {
+  size_t __n      = __b_.size() - 1;
+  result_type __d = (__xmax - __xmin) / __n;
+  __densities_.reserve(__b_.size());
+  for (size_t __i = 0; __i < __n; ++__i) {
+    __b_[__i] = __xmin + __i * __d;
+    __densities_.push_back(__fw(__b_[__i]));
+  }
+  __b_[__n] = __xmax;
+  __densities_.push_back(__fw(__b_[__n]));
+  __init();
+}
+
+template <class _RealType>
+template <class _URNG>
+_RealType piecewise_linear_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p) {
+  static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+  typedef uniform_real_distribution<result_type> _Gen;
+  result_type __u = _Gen()(__g);
+  ptrdiff_t __k   = std::upper_bound(__p.__areas_.begin(), __p.__areas_.end(), __u) - __p.__areas_.begin() - 1;
+  __u -= __p.__areas_[__k];
+  const result_type __dk     = __p.__densities_[__k];
+  const result_type __dk1    = __p.__densities_[__k + 1];
+  const result_type __deltad = __dk1 - __dk;
+  const result_type __bk     = __p.__b_[__k];
+  if (__deltad == 0)
+    return __u / __dk + __bk;
+  const result_type __bk1    = __p.__b_[__k + 1];
+  const result_type __deltab = __bk1 - __bk;
+  return (__bk * __dk1 - __bk1 * __dk + std::sqrt(__deltab * (__deltab * __dk * __dk + 2 * __deltad * __u))) / __deltad;
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const piecewise_linear_distribution<_RT>& __x) {
+  __save_flags<_CharT, _Traits> __lx(__os);
+  typedef basic_ostream<_CharT, _Traits> _OStream;
+  __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);
+  _CharT __sp = __os.widen(' ');
+  __os.fill(__sp);
+  size_t __n = __x.__p_.__b_.size();
+  __os << __n;
+  for (size_t __i = 0; __i < __n; ++__i)
+    __os << __sp << __x.__p_.__b_[__i];
+  __n = __x.__p_.__densities_.size();
+  __os << __sp << __n;
+  for (size_t __i = 0; __i < __n; ++__i)
+    __os << __sp << __x.__p_.__densities_[__i];
+  __n = __x.__p_.__areas_.size();
+  __os << __sp << __n;
+  for (size_t __i = 0; __i < __n; ++__i)
+    __os << __sp << __x.__p_.__areas_[__i];
+  return __os;
+}
+
+template <class _CharT, class _Traits, class _RT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, piecewise_linear_distribution<_RT>& __x) {
+  typedef piecewise_linear_distribution<_RT> _Eng;
+  typedef typename _Eng::result_type result_type;
+  __save_flags<_CharT, _Traits> __lx(__is);
+  typedef basic_istream<_CharT, _Traits> _Istream;
+  __is.flags(_Istream::dec | _Istream::skipws);
+  size_t __n;
+  __is >> __n;
+  vector<result_type> __b(__n);
+  for (size_t __i = 0; __i < __n; ++__i)
+    __is >> __b[__i];
+  __is >> __n;
+  vector<result_type> __densities(__n);
+  for (size_t __i = 0; __i < __n; ++__i)
+    __is >> __densities[__i];
+  __is >> __n;
+  vector<result_type> __areas(__n);
+  for (size_t __i = 0; __i < __n; ++__i)
+    __is >> __areas[__i];
+  if (!__is.fail()) {
+    swap(__x.__p_.__b_, __b);
+    swap(__x.__p_.__densities_, __densities);
+    swap(__x.__p_.__areas_, __areas);
+  }
+  return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_PIECEWISE_LINEAR_DISTRIBUTION_H