| //===----------------------------------------------------------------------===// |
| // |
| // 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_SUBTRACT_WITH_CARRY_ENGINE_H |
| #define _LIBCPP___RANDOM_SUBTRACT_WITH_CARRY_ENGINE_H |
| |
| #include <__algorithm/equal.h> |
| #include <__algorithm/min.h> |
| #include <__config> |
| #include <__random/is_seed_sequence.h> |
| #include <__random/linear_congruential_engine.h> |
| #include <cstddef> |
| #include <cstdint> |
| #include <iosfwd> |
| #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 |
| |
| template<class _UIntType, size_t __w, size_t __s, size_t __r> |
| class _LIBCPP_TEMPLATE_VIS subtract_with_carry_engine; |
| |
| template<class _UInt, size_t _Wp, size_t _Sp, size_t _Rp> |
| bool |
| operator==( |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x, |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __y); |
| |
| template<class _UInt, size_t _Wp, size_t _Sp, size_t _Rp> |
| _LIBCPP_INLINE_VISIBILITY |
| bool |
| operator!=( |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x, |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __y); |
| |
| template <class _CharT, class _Traits, |
| class _UInt, size_t _Wp, size_t _Sp, size_t _Rp> |
| basic_ostream<_CharT, _Traits>& |
| operator<<(basic_ostream<_CharT, _Traits>& __os, |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x); |
| |
| template <class _CharT, class _Traits, |
| class _UInt, size_t _Wp, size_t _Sp, size_t _Rp> |
| basic_istream<_CharT, _Traits>& |
| operator>>(basic_istream<_CharT, _Traits>& __is, |
| subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x); |
| |
| template<class _UIntType, size_t __w, size_t __s, size_t __r> |
| class _LIBCPP_TEMPLATE_VIS subtract_with_carry_engine |
| { |
| public: |
| // types |
| typedef _UIntType result_type; |
| |
| private: |
| result_type __x_[__r]; |
| result_type __c_; |
| size_t __i_; |
| |
| static _LIBCPP_CONSTEXPR const result_type _Dt = numeric_limits<result_type>::digits; |
| static_assert( 0 < __w, "subtract_with_carry_engine invalid parameters"); |
| static_assert(__w <= _Dt, "subtract_with_carry_engine invalid parameters"); |
| static_assert( 0 < __s, "subtract_with_carry_engine invalid parameters"); |
| static_assert(__s < __r, "subtract_with_carry_engine invalid parameters"); |
| public: |
| static _LIBCPP_CONSTEXPR const result_type _Min = 0; |
| static _LIBCPP_CONSTEXPR const result_type _Max = __w == _Dt ? result_type(~0) : |
| (result_type(1) << __w) - result_type(1); |
| static_assert(_Min < _Max, "subtract_with_carry_engine invalid parameters"); |
| |
| // engine characteristics |
| static _LIBCPP_CONSTEXPR const size_t word_size = __w; |
| static _LIBCPP_CONSTEXPR const size_t short_lag = __s; |
| static _LIBCPP_CONSTEXPR const size_t long_lag = __r; |
| _LIBCPP_INLINE_VISIBILITY |
| static _LIBCPP_CONSTEXPR result_type min() { return _Min; } |
| _LIBCPP_INLINE_VISIBILITY |
| static _LIBCPP_CONSTEXPR result_type max() { return _Max; } |
| static _LIBCPP_CONSTEXPR const result_type default_seed = 19780503u; |
| |
| // constructors and seeding functions |
| #ifndef _LIBCPP_CXX03_LANG |
| _LIBCPP_INLINE_VISIBILITY |
| subtract_with_carry_engine() : subtract_with_carry_engine(default_seed) {} |
| _LIBCPP_INLINE_VISIBILITY |
| explicit subtract_with_carry_engine(result_type __sd) { seed(__sd); } |
| #else |
| _LIBCPP_INLINE_VISIBILITY |
| explicit subtract_with_carry_engine(result_type __sd = default_seed) { |
| seed(__sd); |
| } |
| #endif |
| template<class _Sseq> |
| _LIBCPP_INLINE_VISIBILITY |
| explicit subtract_with_carry_engine(_Sseq& __q, |
| typename enable_if<__is_seed_sequence<_Sseq, subtract_with_carry_engine>::value>::type* = 0) |
| {seed(__q);} |
| _LIBCPP_INLINE_VISIBILITY |
| void seed(result_type __sd = default_seed) |
| {seed(__sd, integral_constant<unsigned, 1 + (__w - 1) / 32>());} |
| template<class _Sseq> |
| _LIBCPP_INLINE_VISIBILITY |
| typename enable_if |
| < |
| __is_seed_sequence<_Sseq, subtract_with_carry_engine>::value, |
| void |
| >::type |
| seed(_Sseq& __q) |
| {__seed(__q, integral_constant<unsigned, 1 + (__w - 1) / 32>());} |
| |
| // generating functions |
| result_type operator()(); |
| _LIBCPP_INLINE_VISIBILITY |
| void discard(unsigned long long __z) {for (; __z; --__z) operator()();} |
| |
| template<class _UInt, size_t _Wp, size_t _Sp, size_t _Rp> |
| friend |
| bool |
| operator==( |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x, |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __y); |
| |
| template<class _UInt, size_t _Wp, size_t _Sp, size_t _Rp> |
| friend |
| bool |
| operator!=( |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x, |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __y); |
| |
| template <class _CharT, class _Traits, |
| class _UInt, size_t _Wp, size_t _Sp, size_t _Rp> |
| friend |
| basic_ostream<_CharT, _Traits>& |
| operator<<(basic_ostream<_CharT, _Traits>& __os, |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x); |
| |
| template <class _CharT, class _Traits, |
| class _UInt, size_t _Wp, size_t _Sp, size_t _Rp> |
| friend |
| basic_istream<_CharT, _Traits>& |
| operator>>(basic_istream<_CharT, _Traits>& __is, |
| subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x); |
| |
| private: |
| |
| void seed(result_type __sd, integral_constant<unsigned, 1>); |
| void seed(result_type __sd, integral_constant<unsigned, 2>); |
| template<class _Sseq> |
| void __seed(_Sseq& __q, integral_constant<unsigned, 1>); |
| template<class _Sseq> |
| void __seed(_Sseq& __q, integral_constant<unsigned, 2>); |
| }; |
| |
| template<class _UIntType, size_t __w, size_t __s, size_t __r> |
| _LIBCPP_CONSTEXPR const size_t subtract_with_carry_engine<_UIntType, __w, __s, __r>::word_size; |
| |
| template<class _UIntType, size_t __w, size_t __s, size_t __r> |
| _LIBCPP_CONSTEXPR const size_t subtract_with_carry_engine<_UIntType, __w, __s, __r>::short_lag; |
| |
| template<class _UIntType, size_t __w, size_t __s, size_t __r> |
| _LIBCPP_CONSTEXPR const size_t subtract_with_carry_engine<_UIntType, __w, __s, __r>::long_lag; |
| |
| template<class _UIntType, size_t __w, size_t __s, size_t __r> |
| _LIBCPP_CONSTEXPR const typename subtract_with_carry_engine<_UIntType, __w, __s, __r>::result_type |
| subtract_with_carry_engine<_UIntType, __w, __s, __r>::default_seed; |
| |
| template<class _UIntType, size_t __w, size_t __s, size_t __r> |
| void |
| subtract_with_carry_engine<_UIntType, __w, __s, __r>::seed(result_type __sd, |
| integral_constant<unsigned, 1>) |
| { |
| linear_congruential_engine<result_type, 40014u, 0u, 2147483563u> |
| __e(__sd == 0u ? default_seed : __sd); |
| for (size_t __i = 0; __i < __r; ++__i) |
| __x_[__i] = static_cast<result_type>(__e() & _Max); |
| __c_ = __x_[__r-1] == 0; |
| __i_ = 0; |
| } |
| |
| template<class _UIntType, size_t __w, size_t __s, size_t __r> |
| void |
| subtract_with_carry_engine<_UIntType, __w, __s, __r>::seed(result_type __sd, |
| integral_constant<unsigned, 2>) |
| { |
| linear_congruential_engine<result_type, 40014u, 0u, 2147483563u> |
| __e(__sd == 0u ? default_seed : __sd); |
| for (size_t __i = 0; __i < __r; ++__i) |
| { |
| result_type __e0 = __e(); |
| __x_[__i] = static_cast<result_type>( |
| (__e0 + ((uint64_t)__e() << 32)) & _Max); |
| } |
| __c_ = __x_[__r-1] == 0; |
| __i_ = 0; |
| } |
| |
| template<class _UIntType, size_t __w, size_t __s, size_t __r> |
| template<class _Sseq> |
| void |
| subtract_with_carry_engine<_UIntType, __w, __s, __r>::__seed(_Sseq& __q, |
| integral_constant<unsigned, 1>) |
| { |
| const unsigned __k = 1; |
| uint32_t __ar[__r * __k]; |
| __q.generate(__ar, __ar + __r * __k); |
| for (size_t __i = 0; __i < __r; ++__i) |
| __x_[__i] = static_cast<result_type>(__ar[__i] & _Max); |
| __c_ = __x_[__r-1] == 0; |
| __i_ = 0; |
| } |
| |
| template<class _UIntType, size_t __w, size_t __s, size_t __r> |
| template<class _Sseq> |
| void |
| subtract_with_carry_engine<_UIntType, __w, __s, __r>::__seed(_Sseq& __q, |
| integral_constant<unsigned, 2>) |
| { |
| const unsigned __k = 2; |
| uint32_t __ar[__r * __k]; |
| __q.generate(__ar, __ar + __r * __k); |
| for (size_t __i = 0; __i < __r; ++__i) |
| __x_[__i] = static_cast<result_type>( |
| (__ar[2 * __i] + ((uint64_t)__ar[2 * __i + 1] << 32)) & _Max); |
| __c_ = __x_[__r-1] == 0; |
| __i_ = 0; |
| } |
| |
| template<class _UIntType, size_t __w, size_t __s, size_t __r> |
| _UIntType |
| subtract_with_carry_engine<_UIntType, __w, __s, __r>::operator()() |
| { |
| const result_type& __xs = __x_[(__i_ + (__r - __s)) % __r]; |
| result_type& __xr = __x_[__i_]; |
| result_type __new_c = __c_ == 0 ? __xs < __xr : __xs != 0 ? __xs <= __xr : 1; |
| __xr = (__xs - __xr - __c_) & _Max; |
| __c_ = __new_c; |
| __i_ = (__i_ + 1) % __r; |
| return __xr; |
| } |
| |
| template<class _UInt, size_t _Wp, size_t _Sp, size_t _Rp> |
| bool |
| operator==( |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x, |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __y) |
| { |
| if (__x.__c_ != __y.__c_) |
| return false; |
| if (__x.__i_ == __y.__i_) |
| return _VSTD::equal(__x.__x_, __x.__x_ + _Rp, __y.__x_); |
| if (__x.__i_ == 0 || __y.__i_ == 0) |
| { |
| size_t __j = _VSTD::min(_Rp - __x.__i_, _Rp - __y.__i_); |
| if (!_VSTD::equal(__x.__x_ + __x.__i_, __x.__x_ + __x.__i_ + __j, |
| __y.__x_ + __y.__i_)) |
| return false; |
| if (__x.__i_ == 0) |
| return _VSTD::equal(__x.__x_ + __j, __x.__x_ + _Rp, __y.__x_); |
| return _VSTD::equal(__x.__x_, __x.__x_ + (_Rp - __j), __y.__x_ + __j); |
| } |
| if (__x.__i_ < __y.__i_) |
| { |
| size_t __j = _Rp - __y.__i_; |
| if (!_VSTD::equal(__x.__x_ + __x.__i_, __x.__x_ + (__x.__i_ + __j), |
| __y.__x_ + __y.__i_)) |
| return false; |
| if (!_VSTD::equal(__x.__x_ + (__x.__i_ + __j), __x.__x_ + _Rp, |
| __y.__x_)) |
| return false; |
| return _VSTD::equal(__x.__x_, __x.__x_ + __x.__i_, |
| __y.__x_ + (_Rp - (__x.__i_ + __j))); |
| } |
| size_t __j = _Rp - __x.__i_; |
| if (!_VSTD::equal(__y.__x_ + __y.__i_, __y.__x_ + (__y.__i_ + __j), |
| __x.__x_ + __x.__i_)) |
| return false; |
| if (!_VSTD::equal(__y.__x_ + (__y.__i_ + __j), __y.__x_ + _Rp, |
| __x.__x_)) |
| return false; |
| return _VSTD::equal(__y.__x_, __y.__x_ + __y.__i_, |
| __x.__x_ + (_Rp - (__y.__i_ + __j))); |
| } |
| |
| template<class _UInt, size_t _Wp, size_t _Sp, size_t _Rp> |
| inline _LIBCPP_INLINE_VISIBILITY |
| bool |
| operator!=( |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x, |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __y) |
| { |
| return !(__x == __y); |
| } |
| |
| template <class _CharT, class _Traits, |
| class _UInt, size_t _Wp, size_t _Sp, size_t _Rp> |
| basic_ostream<_CharT, _Traits>& |
| operator<<(basic_ostream<_CharT, _Traits>& __os, |
| const subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __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.__x_[__x.__i_]; |
| for (size_t __j = __x.__i_ + 1; __j < _Rp; ++__j) |
| __os << __sp << __x.__x_[__j]; |
| for (size_t __j = 0; __j < __x.__i_; ++__j) |
| __os << __sp << __x.__x_[__j]; |
| __os << __sp << __x.__c_; |
| return __os; |
| } |
| |
| template <class _CharT, class _Traits, |
| class _UInt, size_t _Wp, size_t _Sp, size_t _Rp> |
| basic_istream<_CharT, _Traits>& |
| operator>>(basic_istream<_CharT, _Traits>& __is, |
| subtract_with_carry_engine<_UInt, _Wp, _Sp, _Rp>& __x) |
| { |
| __save_flags<_CharT, _Traits> __lx(__is); |
| typedef basic_istream<_CharT, _Traits> _Istream; |
| __is.flags(_Istream::dec | _Istream::skipws); |
| _UInt __t[_Rp+1]; |
| for (size_t __i = 0; __i < _Rp+1; ++__i) |
| __is >> __t[__i]; |
| if (!__is.fail()) |
| { |
| for (size_t __i = 0; __i < _Rp; ++__i) |
| __x.__x_[__i] = __t[__i]; |
| __x.__c_ = __t[_Rp]; |
| __x.__i_ = 0; |
| } |
| return __is; |
| } |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| _LIBCPP_POP_MACROS |
| |
| #endif // _LIBCPP___RANDOM_SUBTRACT_WITH_CARRY_ENGINE_H |
