1 files changed, 230 insertions, 0 deletions
diff --git a/contrib/llvm-project/libcxx/include/__random/shuffle_order_engine.h b/contrib/llvm-project/libcxx/include/__random/shuffle_order_engine.h
new file mode 100644
index 000000000000..f54ed17e3838
--- /dev/null
+++ b/contrib/llvm-project/libcxx/include/__random/shuffle_order_engine.h
@@ -0,0 +1,230 @@
+//===----------------------------------------------------------------------===//
+//
+// 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_SHUFFLE_ORDER_ENGINE_H
+#define _LIBCPP___RANDOM_SHUFFLE_ORDER_ENGINE_H
+
+#include <__algorithm/equal.h>
+#include <__config>
+#include <__random/is_seed_sequence.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_convertible.h>
+#include <__utility/move.h>
+#include <cstddef>
+#include <cstdint>
+#include <iosfwd>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <uint64_t _Xp, uint64_t _Yp>
+struct __ugcd {
+  static _LIBCPP_CONSTEXPR const uint64_t value = __ugcd<_Yp, _Xp % _Yp>::value;
+};
+
+template <uint64_t _Xp>
+struct __ugcd<_Xp, 0> {
+  static _LIBCPP_CONSTEXPR const uint64_t value = _Xp;
+};
+
+template <uint64_t _Np, uint64_t _Dp>
+class __uratio {
+  static_assert(_Dp != 0, "__uratio divide by 0");
+  static _LIBCPP_CONSTEXPR const uint64_t __gcd = __ugcd<_Np, _Dp>::value;
+
+public:
+  static _LIBCPP_CONSTEXPR const uint64_t num = _Np / __gcd;
+  static _LIBCPP_CONSTEXPR const uint64_t den = _Dp / __gcd;
+
+  typedef __uratio<num, den> type;
+};
+
+template <class _Engine, size_t __k>
+class _LIBCPP_TEMPLATE_VIS shuffle_order_engine {
+  static_assert(0 < __k, "shuffle_order_engine invalid parameters");
+
+public:
+  // types
+  typedef typename _Engine::result_type result_type;
+
+private:
+  _Engine __e_;
+  result_type __v_[__k];
+  result_type __y_;
+
+public:
+  // engine characteristics
+  static _LIBCPP_CONSTEXPR const size_t table_size = __k;
+
+#ifdef _LIBCPP_CXX03_LANG
+  static const result_type _Min = _Engine::_Min;
+  static const result_type _Max = _Engine::_Max;
+#else
+  static _LIBCPP_CONSTEXPR const result_type _Min = _Engine::min();
+  static _LIBCPP_CONSTEXPR const result_type _Max = _Engine::max();
+#endif
+  static_assert(_Min < _Max, "shuffle_order_engine invalid parameters");
+  _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type min() { return _Min; }
+  _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR result_type max() { return _Max; }
+
+  static _LIBCPP_CONSTEXPR const unsigned long long _Rp = _Max - _Min + 1ull;
+
+  // constructors and seeding functions
+  _LIBCPP_HIDE_FROM_ABI shuffle_order_engine() { __init(); }
+  _LIBCPP_HIDE_FROM_ABI explicit shuffle_order_engine(const _Engine& __e) : __e_(__e) { __init(); }
+#ifndef _LIBCPP_CXX03_LANG
+  _LIBCPP_HIDE_FROM_ABI explicit shuffle_order_engine(_Engine&& __e) : __e_(std::move(__e)) { __init(); }
+#endif // _LIBCPP_CXX03_LANG
+  _LIBCPP_HIDE_FROM_ABI explicit shuffle_order_engine(result_type __sd) : __e_(__sd) { __init(); }
+  template <
+      class _Sseq,
+      __enable_if_t<__is_seed_sequence<_Sseq, shuffle_order_engine>::value && !is_convertible<_Sseq, _Engine>::value,
+                    int> = 0>
+  _LIBCPP_HIDE_FROM_ABI explicit shuffle_order_engine(_Sseq& __q) : __e_(__q) {
+    __init();
+  }
+  _LIBCPP_HIDE_FROM_ABI void seed() {
+    __e_.seed();
+    __init();
+  }
+  _LIBCPP_HIDE_FROM_ABI void seed(result_type __sd) {
+    __e_.seed(__sd);
+    __init();
+  }
+  template <class _Sseq, __enable_if_t<__is_seed_sequence<_Sseq, shuffle_order_engine>::value, int> = 0>
+  _LIBCPP_HIDE_FROM_ABI void seed(_Sseq& __q) {
+    __e_.seed(__q);
+    __init();
+  }
+
+  // generating functions
+  _LIBCPP_HIDE_FROM_ABI result_type operator()() { return __eval(integral_constant<bool, _Rp != 0>()); }
+  _LIBCPP_HIDE_FROM_ABI void discard(unsigned long long __z) {
+    for (; __z; --__z)
+      operator()();
+  }
+
+  // property functions
+  _LIBCPP_HIDE_FROM_ABI const _Engine& base() const _NOEXCEPT { return __e_; }
+
+private:
+  template <class _Eng, size_t _Kp>
+  friend bool operator==(const shuffle_order_engine<_Eng, _Kp>& __x, const shuffle_order_engine<_Eng, _Kp>& __y);
+
+  template <class _Eng, size_t _Kp>
+  friend bool operator!=(const shuffle_order_engine<_Eng, _Kp>& __x, const shuffle_order_engine<_Eng, _Kp>& __y);
+
+  template <class _CharT, class _Traits, class _Eng, size_t _Kp>
+  friend basic_ostream<_CharT, _Traits>&
+  operator<<(basic_ostream<_CharT, _Traits>& __os, const shuffle_order_engine<_Eng, _Kp>& __x);
+
+  template <class _CharT, class _Traits, class _Eng, size_t _Kp>
+  friend basic_istream<_CharT, _Traits>&
+  operator>>(basic_istream<_CharT, _Traits>& __is, shuffle_order_engine<_Eng, _Kp>& __x);
+
+  _LIBCPP_HIDE_FROM_ABI void __init() {
+    for (size_t __i = 0; __i < __k; ++__i)
+      __v_[__i] = __e_();
+    __y_ = __e_();
+  }
+
+  _LIBCPP_HIDE_FROM_ABI result_type __eval(false_type) { return __eval2(integral_constant<bool, __k & 1>()); }
+  _LIBCPP_HIDE_FROM_ABI result_type __eval(true_type) { return __eval(__uratio<__k, _Rp>()); }
+
+  _LIBCPP_HIDE_FROM_ABI result_type __eval2(false_type) { return __eval(__uratio<__k / 2, 0x8000000000000000ull>()); }
+  _LIBCPP_HIDE_FROM_ABI result_type __eval2(true_type) { return __evalf<__k, 0>(); }
+
+  template <uint64_t _Np,
+            uint64_t _Dp,
+            __enable_if_t<(__uratio<_Np, _Dp>::num > 0xFFFFFFFFFFFFFFFFull / (_Max - _Min)), int> = 0>
+  _LIBCPP_HIDE_FROM_ABI result_type __eval(__uratio<_Np, _Dp>) {
+    return __evalf<__uratio<_Np, _Dp>::num, __uratio<_Np, _Dp>::den>();
+  }
+
+  template <uint64_t _Np,
+            uint64_t _Dp,
+            __enable_if_t<__uratio<_Np, _Dp>::num <= 0xFFFFFFFFFFFFFFFFull / (_Max - _Min), int> = 0>
+  _LIBCPP_HIDE_FROM_ABI result_type __eval(__uratio<_Np, _Dp>) {
+    const size_t __j = static_cast<size_t>(__uratio<_Np, _Dp>::num * (__y_ - _Min) / __uratio<_Np, _Dp>::den);
+    __y_             = __v_[__j];
+    __v_[__j]        = __e_();
+    return __y_;
+  }
+
+  template <uint64_t __n, uint64_t __d>
+  _LIBCPP_HIDE_FROM_ABI result_type __evalf() {
+    const double __fp = __d == 0 ? __n / (2. * 0x8000000000000000ull) : __n / (double)__d;
+    const size_t __j  = static_cast<size_t>(__fp * (__y_ - _Min));
+    __y_              = __v_[__j];
+    __v_[__j]         = __e_();
+    return __y_;
+  }
+};
+
+template <class _Engine, size_t __k>
+_LIBCPP_CONSTEXPR const size_t shuffle_order_engine<_Engine, __k>::table_size;
+
+template <class _Eng, size_t _Kp>
+_LIBCPP_HIDE_FROM_ABI bool
+operator==(const shuffle_order_engine<_Eng, _Kp>& __x, const shuffle_order_engine<_Eng, _Kp>& __y) {
+  return __x.__y_ == __y.__y_ && std::equal(__x.__v_, __x.__v_ + _Kp, __y.__v_) && __x.__e_ == __y.__e_;
+}
+
+template <class _Eng, size_t _Kp>
+inline _LIBCPP_HIDE_FROM_ABI bool
+operator!=(const shuffle_order_engine<_Eng, _Kp>& __x, const shuffle_order_engine<_Eng, _Kp>& __y) {
+  return !(__x == __y);
+}
+
+template <class _CharT, class _Traits, class _Eng, size_t _Kp>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const shuffle_order_engine<_Eng, _Kp>& __x) {
+  __save_flags<_CharT, _Traits> __lx(__os);
+  typedef basic_ostream<_CharT, _Traits> _Ostream;
+  __os.flags(_Ostream::dec | _Ostream::left);
+  _CharT __sp = __os.widen(' ');
+  __os.fill(__sp);
+  __os << __x.__e_ << __sp << __x.__v_[0];
+  for (size_t __i = 1; __i < _Kp; ++__i)
+    __os << __sp << __x.__v_[__i];
+  return __os << __sp << __x.__y_;
+}
+
+template <class _CharT, class _Traits, class _Eng, size_t _Kp>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, shuffle_order_engine<_Eng, _Kp>& __x) {
+  typedef typename shuffle_order_engine<_Eng, _Kp>::result_type result_type;
+  __save_flags<_CharT, _Traits> __lx(__is);
+  typedef basic_istream<_CharT, _Traits> _Istream;
+  __is.flags(_Istream::dec | _Istream::skipws);
+  _Eng __e;
+  result_type __vp[_Kp + 1];
+  __is >> __e;
+  for (size_t __i = 0; __i < _Kp + 1; ++__i)
+    __is >> __vp[__i];
+  if (!__is.fail()) {
+    __x.__e_ = __e;
+    for (size_t __i = 0; __i < _Kp; ++__i)
+      __x.__v_[__i] = __vp[__i];
+    __x.__y_ = __vp[_Kp];
+  }
+  return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_SHUFFLE_ORDER_ENGINE_H