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-rw-r--r--contrib/llvm-project/libcxx/include/__random/uniform_int_distribution.h264
1 files changed, 264 insertions, 0 deletions
diff --git a/contrib/llvm-project/libcxx/include/__random/uniform_int_distribution.h b/contrib/llvm-project/libcxx/include/__random/uniform_int_distribution.h
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index 000000000000..4e3ca3efe568
--- /dev/null
+++ b/contrib/llvm-project/libcxx/include/__random/uniform_int_distribution.h
@@ -0,0 +1,264 @@
+//===----------------------------------------------------------------------===//
+//
+// 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_UNIFORM_INT_DISTRIBUTION_H
+#define _LIBCPP___RANDOM_UNIFORM_INT_DISTRIBUTION_H
+
+#include <__bit/countl.h>
+#include <__config>
+#include <__random/is_valid.h>
+#include <__random/log2.h>
+#include <__type_traits/conditional.h>
+#include <__type_traits/make_unsigned.h>
+#include <cstddef>
+#include <cstdint>
+#include <iosfwd>
+#include <limits>
+
+#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 _Engine, class _UIntType>
+class __independent_bits_engine {
+public:
+ // types
+ typedef _UIntType result_type;
+
+private:
+ typedef typename _Engine::result_type _Engine_result_type;
+ typedef __conditional_t<sizeof(_Engine_result_type) <= sizeof(result_type), result_type, _Engine_result_type>
+ _Working_result_type;
+
+ _Engine& __e_;
+ size_t __w_;
+ size_t __w0_;
+ size_t __n_;
+ size_t __n0_;
+ _Working_result_type __y0_;
+ _Working_result_type __y1_;
+ _Engine_result_type __mask0_;
+ _Engine_result_type __mask1_;
+
+#ifdef _LIBCPP_CXX03_LANG
+ static const _Working_result_type _Rp = _Engine::_Max - _Engine::_Min + _Working_result_type(1);
+#else
+ static _LIBCPP_CONSTEXPR const _Working_result_type _Rp = _Engine::max() - _Engine::min() + _Working_result_type(1);
+#endif
+ static _LIBCPP_CONSTEXPR const size_t __m = __log2<_Working_result_type, _Rp>::value;
+ static _LIBCPP_CONSTEXPR const size_t _WDt = numeric_limits<_Working_result_type>::digits;
+ static _LIBCPP_CONSTEXPR const size_t _EDt = numeric_limits<_Engine_result_type>::digits;
+
+public:
+ // constructors and seeding functions
+ _LIBCPP_HIDE_FROM_ABI __independent_bits_engine(_Engine& __e, size_t __w);
+
+ // generating functions
+ _LIBCPP_HIDE_FROM_ABI result_type operator()() { return __eval(integral_constant<bool, _Rp != 0>()); }
+
+private:
+ _LIBCPP_HIDE_FROM_ABI result_type __eval(false_type);
+ _LIBCPP_HIDE_FROM_ABI result_type __eval(true_type);
+};
+
+template <class _Engine, class _UIntType>
+__independent_bits_engine<_Engine, _UIntType>::__independent_bits_engine(_Engine& __e, size_t __w)
+ : __e_(__e), __w_(__w) {
+ __n_ = __w_ / __m + (__w_ % __m != 0);
+ __w0_ = __w_ / __n_;
+ if (_Rp == 0)
+ __y0_ = _Rp;
+ else if (__w0_ < _WDt)
+ __y0_ = (_Rp >> __w0_) << __w0_;
+ else
+ __y0_ = 0;
+ if (_Rp - __y0_ > __y0_ / __n_) {
+ ++__n_;
+ __w0_ = __w_ / __n_;
+ if (__w0_ < _WDt)
+ __y0_ = (_Rp >> __w0_) << __w0_;
+ else
+ __y0_ = 0;
+ }
+ __n0_ = __n_ - __w_ % __n_;
+ if (__w0_ < _WDt - 1)
+ __y1_ = (_Rp >> (__w0_ + 1)) << (__w0_ + 1);
+ else
+ __y1_ = 0;
+ __mask0_ = __w0_ > 0 ? _Engine_result_type(~0) >> (_EDt - __w0_) : _Engine_result_type(0);
+ __mask1_ = __w0_ < _EDt - 1 ? _Engine_result_type(~0) >> (_EDt - (__w0_ + 1)) : _Engine_result_type(~0);
+}
+
+template <class _Engine, class _UIntType>
+inline _UIntType __independent_bits_engine<_Engine, _UIntType>::__eval(false_type) {
+ return static_cast<result_type>(__e_() & __mask0_);
+}
+
+template <class _Engine, class _UIntType>
+_UIntType __independent_bits_engine<_Engine, _UIntType>::__eval(true_type) {
+ const size_t __w_rt = numeric_limits<result_type>::digits;
+ result_type __sp = 0;
+ for (size_t __k = 0; __k < __n0_; ++__k) {
+ _Engine_result_type __u;
+ do {
+ __u = __e_() - _Engine::min();
+ } while (__u >= __y0_);
+ if (__w0_ < __w_rt)
+ __sp <<= __w0_;
+ else
+ __sp = 0;
+ __sp += __u & __mask0_;
+ }
+ for (size_t __k = __n0_; __k < __n_; ++__k) {
+ _Engine_result_type __u;
+ do {
+ __u = __e_() - _Engine::min();
+ } while (__u >= __y1_);
+ if (__w0_ < __w_rt - 1)
+ __sp <<= __w0_ + 1;
+ else
+ __sp = 0;
+ __sp += __u & __mask1_;
+ }
+ return __sp;
+}
+
+template <class _IntType = int>
+class uniform_int_distribution {
+ static_assert(__libcpp_random_is_valid_inttype<_IntType>::value, "IntType must be a supported integer type");
+
+public:
+ // types
+ typedef _IntType result_type;
+
+ class param_type {
+ result_type __a_;
+ result_type __b_;
+
+ public:
+ typedef uniform_int_distribution distribution_type;
+
+ _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __a = 0, result_type __b = numeric_limits<result_type>::max())
+ : __a_(__a), __b_(__b) {}
+
+ _LIBCPP_HIDE_FROM_ABI result_type a() const { return __a_; }
+ _LIBCPP_HIDE_FROM_ABI result_type b() const { return __b_; }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool operator==(const param_type& __x, const param_type& __y) {
+ return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;
+ }
+ _LIBCPP_HIDE_FROM_ABI friend bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructors and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ _LIBCPP_HIDE_FROM_ABI uniform_int_distribution() : uniform_int_distribution(0) {}
+ _LIBCPP_HIDE_FROM_ABI explicit uniform_int_distribution(
+ result_type __a, result_type __b = numeric_limits<result_type>::max())
+ : __p_(param_type(__a, __b)) {}
+#else
+ explicit uniform_int_distribution(result_type __a = 0, result_type __b = numeric_limits<result_type>::max())
+ : __p_(param_type(__a, __b)) {}
+#endif
+ _LIBCPP_HIDE_FROM_ABI explicit uniform_int_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 result_type a() const { return __p_.a(); }
+ _LIBCPP_HIDE_FROM_ABI result_type b() const { return __p_.b(); }
+
+ _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 a(); }
+ _LIBCPP_HIDE_FROM_ABI result_type max() const { return b(); }
+
+ _LIBCPP_HIDE_FROM_ABI friend bool
+ operator==(const uniform_int_distribution& __x, const uniform_int_distribution& __y) {
+ return __x.__p_ == __y.__p_;
+ }
+ _LIBCPP_HIDE_FROM_ABI friend bool
+ operator!=(const uniform_int_distribution& __x, const uniform_int_distribution& __y) {
+ return !(__x == __y);
+ }
+};
+
+template <class _IntType>
+template <class _URNG>
+typename uniform_int_distribution<_IntType>::result_type uniform_int_distribution<_IntType>::operator()(
+ _URNG& __g, const param_type& __p) _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK {
+ static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
+ typedef __conditional_t<sizeof(result_type) <= sizeof(uint32_t), uint32_t, __make_unsigned_t<result_type> > _UIntType;
+ const _UIntType __rp = _UIntType(__p.b()) - _UIntType(__p.a()) + _UIntType(1);
+ if (__rp == 1)
+ return __p.a();
+ const size_t __dt = numeric_limits<_UIntType>::digits;
+ typedef __independent_bits_engine<_URNG, _UIntType> _Eng;
+ if (__rp == 0)
+ return static_cast<result_type>(_Eng(__g, __dt)());
+ size_t __w = __dt - std::__countl_zero(__rp) - 1;
+ if ((__rp & (numeric_limits<_UIntType>::max() >> (__dt - __w))) != 0)
+ ++__w;
+ _Eng __e(__g, __w);
+ _UIntType __u;
+ do {
+ __u = __e();
+ } while (__u >= __rp);
+ return static_cast<result_type>(__u + __p.a());
+}
+
+template <class _CharT, class _Traits, class _IT>
+_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
+operator<<(basic_ostream<_CharT, _Traits>& __os, const uniform_int_distribution<_IT>& __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);
+ return __os << __x.a() << __sp << __x.b();
+}
+
+template <class _CharT, class _Traits, class _IT>
+_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
+operator>>(basic_istream<_CharT, _Traits>& __is, uniform_int_distribution<_IT>& __x) {
+ typedef uniform_int_distribution<_IT> _Eng;
+ typedef typename _Eng::result_type result_type;
+ typedef typename _Eng::param_type param_type;
+ __save_flags<_CharT, _Traits> __lx(__is);
+ typedef basic_istream<_CharT, _Traits> _Istream;
+ __is.flags(_Istream::dec | _Istream::skipws);
+ result_type __a;
+ result_type __b;
+ __is >> __a >> __b;
+ if (!__is.fail())
+ __x.param(param_type(__a, __b));
+ return __is;
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___RANDOM_UNIFORM_INT_DISTRIBUTION_H