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Diffstat (limited to 'aarch64-none-linux-gnu/include/c++/13.2.1/bit')
| -rw-r--r-- | aarch64-none-linux-gnu/include/c++/13.2.1/bit | 482 |
1 files changed, 482 insertions, 0 deletions
diff --git a/aarch64-none-linux-gnu/include/c++/13.2.1/bit b/aarch64-none-linux-gnu/include/c++/13.2.1/bit new file mode 100644 index 0000000..5eb4021 --- /dev/null +++ b/aarch64-none-linux-gnu/include/c++/13.2.1/bit @@ -0,0 +1,482 @@ +// <bit> -*- C++ -*- + +// Copyright (C) 2018-2023 Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 3, or (at your option) +// any later version. + +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. + +// Under Section 7 of GPL version 3, you are granted additional +// permissions described in the GCC Runtime Library Exception, version +// 3.1, as published by the Free Software Foundation. + +// You should have received a copy of the GNU General Public License and +// a copy of the GCC Runtime Library Exception along with this program; +// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see +// <http://www.gnu.org/licenses/>. + +/** @file include/bit + * This is a Standard C++ Library header. + */ + +#ifndef _GLIBCXX_BIT +#define _GLIBCXX_BIT 1 + +#pragma GCC system_header + +#if __cplusplus >= 201402L + +#include <type_traits> + +#if _GLIBCXX_HOSTED || __has_include(<ext/numeric_traits.h>) +# include <ext/numeric_traits.h> +#else +# include <limits> +/// @cond undocumented +namespace __gnu_cxx +{ + template<typename _Tp> + struct __int_traits + { + static constexpr int __digits = std::numeric_limits<_Tp>::digits; + static constexpr _Tp __max = std::numeric_limits<_Tp>::max(); + }; +} +/// @endcond +#endif + +namespace std _GLIBCXX_VISIBILITY(default) +{ +_GLIBCXX_BEGIN_NAMESPACE_VERSION + + /** + * @defgroup bit_manip Bit manipulation + * @ingroup numerics + * + * Utilities for examining and manipulating individual bits. + * + * @{ + */ + +#if __cplusplus > 201703l && __has_builtin(__builtin_bit_cast) +#define __cpp_lib_bit_cast 201806L + + /// Create a value of type `To` from the bits of `from`. + /** + * @tparam _To A trivially-copyable type. + * @param __from A trivially-copyable object of the same size as `_To`. + * @return An object of type `_To`. + * @since C++20 + */ + template<typename _To, typename _From> + [[nodiscard]] + constexpr _To + bit_cast(const _From& __from) noexcept +#ifdef __cpp_concepts + requires (sizeof(_To) == sizeof(_From)) + && __is_trivially_copyable(_To) && __is_trivially_copyable(_From) +#endif + { + return __builtin_bit_cast(_To, __from); + } +#endif + +#if __cplusplus > 202002L +#define __cpp_lib_byteswap 202110L + + /// Reverse order of bytes in the object representation of `value`. + /** + * @tparam _Tp An integral type. + * @param __value An object of integer type. + * @return An object of the same type, with the bytes reversed. + * @since C++23 + */ + template<typename _Tp> + [[nodiscard]] + constexpr enable_if_t<is_integral<_Tp>::value, _Tp> + byteswap(_Tp __value) noexcept + { + if constexpr (sizeof(_Tp) == 1) + return __value; +#if __cpp_if_consteval >= 202106L && __CHAR_BIT__ == 8 + if !consteval + { + if constexpr (sizeof(_Tp) == 2) + return __builtin_bswap16(__value); + if constexpr (sizeof(_Tp) == 4) + return __builtin_bswap32(__value); + if constexpr (sizeof(_Tp) == 8) + return __builtin_bswap64(__value); + if constexpr (sizeof(_Tp) == 16) +#if __has_builtin(__builtin_bswap128) + return __builtin_bswap128(__value); +#else + return (__builtin_bswap64(__value >> 64) + | (static_cast<_Tp>(__builtin_bswap64(__value)) << 64)); +#endif + } +#endif + + // Fallback implementation that handles even __int24 etc. + using _Up = typename __make_unsigned<__remove_cv_t<_Tp>>::__type; + size_t __diff = __CHAR_BIT__ * (sizeof(_Tp) - 1); + _Up __mask1 = static_cast<unsigned char>(~0); + _Up __mask2 = __mask1 << __diff; + _Up __val = __value; + for (size_t __i = 0; __i < sizeof(_Tp) / 2; ++__i) + { + _Up __byte1 = __val & __mask1; + _Up __byte2 = __val & __mask2; + __val = (__val ^ __byte1 ^ __byte2 + ^ (__byte1 << __diff) ^ (__byte2 >> __diff)); + __mask1 <<= __CHAR_BIT__; + __mask2 >>= __CHAR_BIT__; + __diff -= 2 * __CHAR_BIT__; + } + return __val; + } +#endif + + /// @cond undocumented + + template<typename _Tp> + constexpr _Tp + __rotl(_Tp __x, int __s) noexcept + { + constexpr auto _Nd = __gnu_cxx::__int_traits<_Tp>::__digits; + if _GLIBCXX17_CONSTEXPR ((_Nd & (_Nd - 1)) == 0) + { + // Variant for power of two _Nd which the compiler can + // easily pattern match. + constexpr unsigned __uNd = _Nd; + const unsigned __r = __s; + return (__x << (__r % __uNd)) | (__x >> ((-__r) % __uNd)); + } + const int __r = __s % _Nd; + if (__r == 0) + return __x; + else if (__r > 0) + return (__x << __r) | (__x >> ((_Nd - __r) % _Nd)); + else + return (__x >> -__r) | (__x << ((_Nd + __r) % _Nd)); // rotr(x, -r) + } + + template<typename _Tp> + constexpr _Tp + __rotr(_Tp __x, int __s) noexcept + { + constexpr auto _Nd = __gnu_cxx::__int_traits<_Tp>::__digits; + if _GLIBCXX17_CONSTEXPR ((_Nd & (_Nd - 1)) == 0) + { + // Variant for power of two _Nd which the compiler can + // easily pattern match. + constexpr unsigned __uNd = _Nd; + const unsigned __r = __s; + return (__x >> (__r % __uNd)) | (__x << ((-__r) % __uNd)); + } + const int __r = __s % _Nd; + if (__r == 0) + return __x; + else if (__r > 0) + return (__x >> __r) | (__x << ((_Nd - __r) % _Nd)); + else + return (__x << -__r) | (__x >> ((_Nd + __r) % _Nd)); // rotl(x, -r) + } + + template<typename _Tp> + constexpr int + __countl_zero(_Tp __x) noexcept + { + using __gnu_cxx::__int_traits; + constexpr auto _Nd = __int_traits<_Tp>::__digits; + + if (__x == 0) + return _Nd; + + constexpr auto _Nd_ull = __int_traits<unsigned long long>::__digits; + constexpr auto _Nd_ul = __int_traits<unsigned long>::__digits; + constexpr auto _Nd_u = __int_traits<unsigned>::__digits; + + if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_u) + { + constexpr int __diff = _Nd_u - _Nd; + return __builtin_clz(__x) - __diff; + } + else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ul) + { + constexpr int __diff = _Nd_ul - _Nd; + return __builtin_clzl(__x) - __diff; + } + else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ull) + { + constexpr int __diff = _Nd_ull - _Nd; + return __builtin_clzll(__x) - __diff; + } + else // (_Nd > _Nd_ull) + { + static_assert(_Nd <= (2 * _Nd_ull), + "Maximum supported integer size is 128-bit"); + + unsigned long long __high = __x >> _Nd_ull; + if (__high != 0) + { + constexpr int __diff = (2 * _Nd_ull) - _Nd; + return __builtin_clzll(__high) - __diff; + } + constexpr auto __max_ull = __int_traits<unsigned long long>::__max; + unsigned long long __low = __x & __max_ull; + return (_Nd - _Nd_ull) + __builtin_clzll(__low); + } + } + + template<typename _Tp> + constexpr int + __countl_one(_Tp __x) noexcept + { + return std::__countl_zero<_Tp>((_Tp)~__x); + } + + template<typename _Tp> + constexpr int + __countr_zero(_Tp __x) noexcept + { + using __gnu_cxx::__int_traits; + constexpr auto _Nd = __int_traits<_Tp>::__digits; + + if (__x == 0) + return _Nd; + + constexpr auto _Nd_ull = __int_traits<unsigned long long>::__digits; + constexpr auto _Nd_ul = __int_traits<unsigned long>::__digits; + constexpr auto _Nd_u = __int_traits<unsigned>::__digits; + + if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_u) + return __builtin_ctz(__x); + else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ul) + return __builtin_ctzl(__x); + else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ull) + return __builtin_ctzll(__x); + else // (_Nd > _Nd_ull) + { + static_assert(_Nd <= (2 * _Nd_ull), + "Maximum supported integer size is 128-bit"); + + constexpr auto __max_ull = __int_traits<unsigned long long>::__max; + unsigned long long __low = __x & __max_ull; + if (__low != 0) + return __builtin_ctzll(__low); + unsigned long long __high = __x >> _Nd_ull; + return __builtin_ctzll(__high) + _Nd_ull; + } + } + + template<typename _Tp> + constexpr int + __countr_one(_Tp __x) noexcept + { + return std::__countr_zero((_Tp)~__x); + } + + template<typename _Tp> + constexpr int + __popcount(_Tp __x) noexcept + { + using __gnu_cxx::__int_traits; + constexpr auto _Nd = __int_traits<_Tp>::__digits; + + constexpr auto _Nd_ull = __int_traits<unsigned long long>::__digits; + constexpr auto _Nd_ul = __int_traits<unsigned long>::__digits; + constexpr auto _Nd_u = __int_traits<unsigned>::__digits; + + if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_u) + return __builtin_popcount(__x); + else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ul) + return __builtin_popcountl(__x); + else if _GLIBCXX17_CONSTEXPR (_Nd <= _Nd_ull) + return __builtin_popcountll(__x); + else // (_Nd > _Nd_ull) + { + static_assert(_Nd <= (2 * _Nd_ull), + "Maximum supported integer size is 128-bit"); + + constexpr auto __max_ull = __int_traits<unsigned long long>::__max; + unsigned long long __low = __x & __max_ull; + unsigned long long __high = __x >> _Nd_ull; + return __builtin_popcountll(__low) + __builtin_popcountll(__high); + } + } + + template<typename _Tp> + constexpr bool + __has_single_bit(_Tp __x) noexcept + { return std::__popcount(__x) == 1; } + + template<typename _Tp> + constexpr _Tp + __bit_ceil(_Tp __x) noexcept + { + using __gnu_cxx::__int_traits; + constexpr auto _Nd = __int_traits<_Tp>::__digits; + if (__x == 0 || __x == 1) + return 1; + auto __shift_exponent = _Nd - std::__countl_zero((_Tp)(__x - 1u)); + // If the shift exponent equals _Nd then the correct result is not + // representable as a value of _Tp, and so the result is undefined. + // Want that undefined behaviour to be detected in constant expressions, + // by UBSan, and by debug assertions. + if (!std::__is_constant_evaluated()) + { + __glibcxx_assert( __shift_exponent != __int_traits<_Tp>::__digits ); + } + + using __promoted_type = decltype(__x << 1); + if _GLIBCXX17_CONSTEXPR (!is_same<__promoted_type, _Tp>::value) + { + // If __x undergoes integral promotion then shifting by _Nd is + // not undefined. In order to make the shift undefined, so that + // it is diagnosed in constant expressions and by UBsan, we also + // need to "promote" the shift exponent to be too large for the + // promoted type. + const int __extra_exp = sizeof(__promoted_type) / sizeof(_Tp) / 2; + __shift_exponent |= (__shift_exponent & _Nd) << __extra_exp; + } + return (_Tp)1u << __shift_exponent; + } + + template<typename _Tp> + constexpr _Tp + __bit_floor(_Tp __x) noexcept + { + constexpr auto _Nd = __gnu_cxx::__int_traits<_Tp>::__digits; + if (__x == 0) + return 0; + return (_Tp)1u << (_Nd - std::__countl_zero((_Tp)(__x >> 1))); + } + + template<typename _Tp> + constexpr int + __bit_width(_Tp __x) noexcept + { + constexpr auto _Nd = __gnu_cxx::__int_traits<_Tp>::__digits; + return _Nd - std::__countl_zero(__x); + } + + /// @endcond + +#if __cplusplus > 201703L + +#define __cpp_lib_bitops 201907L + + /// @cond undocumented + template<typename _Tp, typename _Up = _Tp> + using _If_is_unsigned_integer + = enable_if_t<__is_unsigned_integer<_Tp>::value, _Up>; + /// @endcond + + // [bit.rot], rotating + + /// Rotate `x` to the left by `s` bits. + template<typename _Tp> + [[nodiscard]] constexpr _If_is_unsigned_integer<_Tp> + rotl(_Tp __x, int __s) noexcept + { return std::__rotl(__x, __s); } + + /// Rotate `x` to the right by `s` bits. + template<typename _Tp> + [[nodiscard]] constexpr _If_is_unsigned_integer<_Tp> + rotr(_Tp __x, int __s) noexcept + { return std::__rotr(__x, __s); } + + // [bit.count], counting + + /// The number of contiguous zero bits, starting from the highest bit. + template<typename _Tp> + constexpr _If_is_unsigned_integer<_Tp, int> + countl_zero(_Tp __x) noexcept + { return std::__countl_zero(__x); } + + /// The number of contiguous one bits, starting from the highest bit. + template<typename _Tp> + constexpr _If_is_unsigned_integer<_Tp, int> + countl_one(_Tp __x) noexcept + { return std::__countl_one(__x); } + + /// The number of contiguous zero bits, starting from the lowest bit. + template<typename _Tp> + constexpr _If_is_unsigned_integer<_Tp, int> + countr_zero(_Tp __x) noexcept + { return std::__countr_zero(__x); } + + /// The number of contiguous one bits, starting from the lowest bit. + template<typename _Tp> + constexpr _If_is_unsigned_integer<_Tp, int> + countr_one(_Tp __x) noexcept + { return std::__countr_one(__x); } + + /// The number of bits set in `x`. + template<typename _Tp> + constexpr _If_is_unsigned_integer<_Tp, int> + popcount(_Tp __x) noexcept + { return std::__popcount(__x); } + + // [bit.pow.two], integral powers of 2 + +#define __cpp_lib_int_pow2 202002L + + /// True if `x` is a power of two, false otherwise. + template<typename _Tp> + constexpr _If_is_unsigned_integer<_Tp, bool> + has_single_bit(_Tp __x) noexcept + { return std::__has_single_bit(__x); } + + /// The smallest power-of-two not less than `x`. + template<typename _Tp> + constexpr _If_is_unsigned_integer<_Tp> + bit_ceil(_Tp __x) noexcept + { return std::__bit_ceil(__x); } + + /// The largest power-of-two not greater than `x`. + template<typename _Tp> + constexpr _If_is_unsigned_integer<_Tp> + bit_floor(_Tp __x) noexcept + { return std::__bit_floor(__x); } + + // _GLIBCXX_RESOLVE_LIB_DEFECTS + // 3656. Inconsistent bit operations returning a count + /// The smallest integer greater than the base-2 logarithm of `x`. + template<typename _Tp> + constexpr _If_is_unsigned_integer<_Tp, int> + bit_width(_Tp __x) noexcept + { return std::__bit_width(__x); } + +#define __cpp_lib_endian 201907L + + /// Byte order constants + /** + * The platform endianness can be checked by comparing `std::endian::native` + * to one of `std::endian::big` or `std::endian::little`. + * + * @since C++20 + */ + enum class endian + { + little = __ORDER_LITTLE_ENDIAN__, + big = __ORDER_BIG_ENDIAN__, + native = __BYTE_ORDER__ + }; +#endif // C++2a + + /// @} + +_GLIBCXX_END_NAMESPACE_VERSION +} // namespace std + +#endif // C++14 +#endif // _GLIBCXX_BIT |