diff options
Diffstat (limited to 'current/sources/cxx-stl/llvm-libc++/include/bit')
| -rw-r--r-- | current/sources/cxx-stl/llvm-libc++/include/bit | 486 |
1 files changed, 486 insertions, 0 deletions
diff --git a/current/sources/cxx-stl/llvm-libc++/include/bit b/current/sources/cxx-stl/llvm-libc++/include/bit new file mode 100644 index 000000000..6dc85b5d0 --- /dev/null +++ b/current/sources/cxx-stl/llvm-libc++/include/bit @@ -0,0 +1,486 @@ +// -*- C++ -*- +//===------------------------------ bit ----------------------------------===// +// +// 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_BIT +#define _LIBCPP_BIT + +/* + bit synopsis + +namespace std { + + template <class T> + constexpr bool ispow2(T x) noexcept; // C++20 + template <class T> + constexpr T ceil2(T x); // C++20 + template <class T> + constexpr T floor2(T x) noexcept; // C++20 + template <class T> + constexpr T log2p1(T x) noexcept; // C++20 + + // 23.20.2, rotating + template<class T> + constexpr T rotl(T x, unsigned int s) noexcept; // C++20 + template<class T> + constexpr T rotr(T x, unsigned int s) noexcept; // C++20 + + // 23.20.3, counting + template<class T> + constexpr int countl_zero(T x) noexcept; // C++20 + template<class T> + constexpr int countl_one(T x) noexcept; // C++20 + template<class T> + constexpr int countr_zero(T x) noexcept; // C++20 + template<class T> + constexpr int countr_one(T x) noexcept; // C++20 + template<class T> + constexpr int popcount(T x) noexcept; // C++20 + + // 20.15.9, endian + enum class endian { + little = see below, // C++20 + big = see below, // C++20 + native = see below // C++20 +}; + +} // namespace std + +*/ + +#include <__config> +#include <limits> +#include <type_traits> +#include <version> +#include <__debug> + +#if defined(__IBMCPP__) +#include "support/ibm/support.h" +#endif +#if defined(_LIBCPP_COMPILER_MSVC) +#include <intrin.h> +#endif + +#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) +#pragma GCC system_header +#endif + +_LIBCPP_PUSH_MACROS +#include <__undef_macros> + +_LIBCPP_BEGIN_NAMESPACE_STD + +#ifndef _LIBCPP_COMPILER_MSVC + +inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR +int __libcpp_ctz(unsigned __x) _NOEXCEPT { return __builtin_ctz(__x); } + +inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR +int __libcpp_ctz(unsigned long __x) _NOEXCEPT { return __builtin_ctzl(__x); } + +inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR +int __libcpp_ctz(unsigned long long __x) _NOEXCEPT { return __builtin_ctzll(__x); } + + +inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR +int __libcpp_clz(unsigned __x) _NOEXCEPT { return __builtin_clz(__x); } + +inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR +int __libcpp_clz(unsigned long __x) _NOEXCEPT { return __builtin_clzl(__x); } + +inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR +int __libcpp_clz(unsigned long long __x) _NOEXCEPT { return __builtin_clzll(__x); } + + +inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR +int __libcpp_popcount(unsigned __x) _NOEXCEPT { return __builtin_popcount(__x); } + +inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR +int __libcpp_popcount(unsigned long __x) _NOEXCEPT { return __builtin_popcountl(__x); } + +inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR +int __libcpp_popcount(unsigned long long __x) _NOEXCEPT { return __builtin_popcountll(__x); } + +#else // _LIBCPP_COMPILER_MSVC + +// Precondition: __x != 0 +inline _LIBCPP_INLINE_VISIBILITY +int __libcpp_ctz(unsigned __x) { + static_assert(sizeof(unsigned) == sizeof(unsigned long), ""); + static_assert(sizeof(unsigned long) == 4, ""); + unsigned long __where; + if (_BitScanForward(&__where, __x)) + return static_cast<int>(__where); + return 32; +} + +inline _LIBCPP_INLINE_VISIBILITY +int __libcpp_ctz(unsigned long __x) { + static_assert(sizeof(unsigned long) == sizeof(unsigned), ""); + return __ctz(static_cast<unsigned>(__x)); +} + +inline _LIBCPP_INLINE_VISIBILITY +int __libcpp_ctz(unsigned long long __x) { + unsigned long __where; +#if defined(_LIBCPP_HAS_BITSCAN64) + (defined(_M_AMD64) || defined(__x86_64__)) + if (_BitScanForward64(&__where, __x)) + return static_cast<int>(__where); +#else + // Win32 doesn't have _BitScanForward64 so emulate it with two 32 bit calls. + if (_BitScanForward(&__where, static_cast<unsigned long>(__x))) + return static_cast<int>(__where); + if (_BitScanForward(&__where, static_cast<unsigned long>(__x >> 32))) + return static_cast<int>(__where + 32); +#endif + return 64; +} + +// Precondition: __x != 0 +inline _LIBCPP_INLINE_VISIBILITY +int __libcpp_clz(unsigned __x) { + static_assert(sizeof(unsigned) == sizeof(unsigned long), ""); + static_assert(sizeof(unsigned long) == 4, ""); + unsigned long __where; + if (_BitScanReverse(&__where, __x)) + return static_cast<int>(31 - __where); + return 32; // Undefined Behavior. +} + +inline _LIBCPP_INLINE_VISIBILITY +int __libcpp_clz(unsigned long __x) { + static_assert(sizeof(unsigned) == sizeof(unsigned long), ""); + return __libcpp_clz(static_cast<unsigned>(__x)); +} + +inline _LIBCPP_INLINE_VISIBILITY +int __libcpp_clz(unsigned long long __x) { + unsigned long __where; +#if defined(_LIBCPP_HAS_BITSCAN64) + if (_BitScanReverse64(&__where, __x)) + return static_cast<int>(63 - __where); +#else + // Win32 doesn't have _BitScanReverse64 so emulate it with two 32 bit calls. + if (_BitScanReverse(&__where, static_cast<unsigned long>(__x >> 32))) + return static_cast<int>(63 - (__where + 32)); + if (_BitScanReverse(&__where, static_cast<unsigned long>(__x))) + return static_cast<int>(63 - __where); +#endif + return 64; // Undefined Behavior. +} + +inline _LIBCPP_INLINE_VISIBILITY int __libcpp_popcount(unsigned __x) { + static_assert(sizeof(unsigned) == 4, ""); + return __popcnt(__x); +} + +inline _LIBCPP_INLINE_VISIBILITY int __libcpp_popcount(unsigned long __x) { + static_assert(sizeof(unsigned long) == 4, ""); + return __popcnt(__x); +} + +inline _LIBCPP_INLINE_VISIBILITY int __libcpp_popcount(unsigned long long __x) { + static_assert(sizeof(unsigned long long) == 8, ""); + return __popcnt64(__x); +} + +#endif // _LIBCPP_COMPILER_MSVC + +template <class _Tp> +using __bitop_unsigned_integer _LIBCPP_NODEBUG_TYPE = integral_constant<bool, + is_integral<_Tp>::value && + is_unsigned<_Tp>::value && + _IsNotSame<typename remove_cv<_Tp>::type, bool>::value && + _IsNotSame<typename remove_cv<_Tp>::type, signed char>::value && + _IsNotSame<typename remove_cv<_Tp>::type, wchar_t>::value && + _IsNotSame<typename remove_cv<_Tp>::type, char16_t>::value && + _IsNotSame<typename remove_cv<_Tp>::type, char32_t>::value + >; + + +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 +_Tp __rotl(_Tp __t, unsigned int __cnt) _NOEXCEPT +{ + static_assert(__bitop_unsigned_integer<_Tp>::value, "__rotl requires unsigned"); + const unsigned int __dig = numeric_limits<_Tp>::digits; + if ((__cnt % __dig) == 0) + return __t; + return (__t << (__cnt % __dig)) | (__t >> (__dig - (__cnt % __dig))); +} + + +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 +_Tp __rotr(_Tp __t, unsigned int __cnt) _NOEXCEPT +{ + static_assert(__bitop_unsigned_integer<_Tp>::value, "__rotr requires unsigned"); + const unsigned int __dig = numeric_limits<_Tp>::digits; + if ((__cnt % __dig) == 0) + return __t; + return (__t >> (__cnt % __dig)) | (__t << (__dig - (__cnt % __dig))); +} + + + +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 +int __countr_zero(_Tp __t) _NOEXCEPT +{ + static_assert(__bitop_unsigned_integer<_Tp>::value, "__countr_zero requires unsigned"); + if (__t == 0) + return numeric_limits<_Tp>::digits; + + if (sizeof(_Tp) <= sizeof(unsigned int)) + return __libcpp_ctz(static_cast<unsigned int>(__t)); + else if (sizeof(_Tp) <= sizeof(unsigned long)) + return __libcpp_ctz(static_cast<unsigned long>(__t)); + else if (sizeof(_Tp) <= sizeof(unsigned long long)) + return __libcpp_ctz(static_cast<unsigned long long>(__t)); + else + { + int __ret = 0; + int __iter = 0; + const unsigned int __ulldigits = numeric_limits<unsigned long long>::digits; + while ((__iter = __libcpp_ctz(static_cast<unsigned long long>(__t))) == __ulldigits) + { + __ret += __iter; + __t >>= __ulldigits; + } + return __ret + __iter; + } +} + +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 +int __countl_zero(_Tp __t) _NOEXCEPT +{ + static_assert(__bitop_unsigned_integer<_Tp>::value, "__countl_zero requires unsigned"); + if (__t == 0) + return numeric_limits<_Tp>::digits; + + if (sizeof(_Tp) <= sizeof(unsigned int)) + return __libcpp_clz(static_cast<unsigned int>(__t)) + - (numeric_limits<unsigned int>::digits - numeric_limits<_Tp>::digits); + else if (sizeof(_Tp) <= sizeof(unsigned long)) + return __libcpp_clz(static_cast<unsigned long>(__t)) + - (numeric_limits<unsigned long>::digits - numeric_limits<_Tp>::digits); + else if (sizeof(_Tp) <= sizeof(unsigned long long)) + return __libcpp_clz(static_cast<unsigned long long>(__t)) + - (numeric_limits<unsigned long long>::digits - numeric_limits<_Tp>::digits); + else + { + int __ret = 0; + int __iter = 0; + const unsigned int __ulldigits = numeric_limits<unsigned long long>::digits; + while (true) { + __t = __rotr(__t, __ulldigits); + if ((__iter = __countl_zero(static_cast<unsigned long long>(__t))) != __ulldigits) + break; + __ret += __iter; + } + return __ret + __iter; + } +} + +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 +int __countl_one(_Tp __t) _NOEXCEPT +{ + static_assert(__bitop_unsigned_integer<_Tp>::value, "__countl_one requires unsigned"); + return __t != numeric_limits<_Tp>::max() + ? __countl_zero(static_cast<_Tp>(~__t)) + : numeric_limits<_Tp>::digits; +} + + +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 +int __countr_one(_Tp __t) _NOEXCEPT +{ + static_assert(__bitop_unsigned_integer<_Tp>::value, "__countr_one requires unsigned"); + return __t != numeric_limits<_Tp>::max() + ? __countr_zero(static_cast<_Tp>(~__t)) + : numeric_limits<_Tp>::digits; +} + + +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 +int +__popcount(_Tp __t) _NOEXCEPT +{ + static_assert(__bitop_unsigned_integer<_Tp>::value, "__libcpp_popcount requires unsigned"); + if (sizeof(_Tp) <= sizeof(unsigned int)) + return __libcpp_popcount(static_cast<unsigned int>(__t)); + else if (sizeof(_Tp) <= sizeof(unsigned long)) + return __libcpp_popcount(static_cast<unsigned long>(__t)); + else if (sizeof(_Tp) <= sizeof(unsigned long long)) + return __libcpp_popcount(static_cast<unsigned long long>(__t)); + else + { + int __ret = 0; + while (__t != 0) + { + __ret += __libcpp_popcount(static_cast<unsigned long long>(__t)); + __t >>= numeric_limits<unsigned long long>::digits; + } + return __ret; + } +} + + +// integral log base 2 +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 +unsigned __bit_log2(_Tp __t) _NOEXCEPT +{ + static_assert(__bitop_unsigned_integer<_Tp>::value, "__bit_log2 requires unsigned"); + return std::numeric_limits<_Tp>::digits - 1 - __countl_zero(__t); +} + +template <class _Tp> +_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR +bool __ispow2(_Tp __t) _NOEXCEPT +{ + static_assert(__bitop_unsigned_integer<_Tp>::value, "__ispow2 requires unsigned"); + return __t != 0 && (((__t & (__t - 1)) == 0)); +} + + +#if _LIBCPP_STD_VER > 17 + +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY constexpr +enable_if_t<__bitop_unsigned_integer<_Tp>::value, _Tp> +rotl(_Tp __t, unsigned int __cnt) noexcept +{ + return __rotl(__t, __cnt); +} + + +// rotr +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY constexpr +enable_if_t<__bitop_unsigned_integer<_Tp>::value, _Tp> +rotr(_Tp __t, unsigned int __cnt) noexcept +{ + return __rotr(__t, __cnt); +} + + +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY constexpr +enable_if_t<__bitop_unsigned_integer<_Tp>::value, int> +countl_zero(_Tp __t) noexcept +{ + return __countl_zero(__t); +} + + +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY constexpr +enable_if_t<__bitop_unsigned_integer<_Tp>::value, int> +countl_one(_Tp __t) noexcept +{ + return __countl_one(__t); +} + + +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY constexpr +enable_if_t<__bitop_unsigned_integer<_Tp>::value, int> +countr_zero(_Tp __t) noexcept +{ + return __countr_zero(__t); +} + + +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY constexpr +enable_if_t<__bitop_unsigned_integer<_Tp>::value, int> +countr_one(_Tp __t) noexcept +{ + return __countr_one(__t); +} + + +template<class _Tp> +_LIBCPP_INLINE_VISIBILITY constexpr +enable_if_t<__bitop_unsigned_integer<_Tp>::value, int> +popcount(_Tp __t) noexcept +{ + return __popcount(__t); +} + + +template <class _Tp> +_LIBCPP_INLINE_VISIBILITY constexpr +enable_if_t<__bitop_unsigned_integer<_Tp>::value, bool> +ispow2(_Tp __t) noexcept +{ + return __ispow2(__t); +} + +template <class _Tp> +_LIBCPP_INLINE_VISIBILITY constexpr +enable_if_t<__bitop_unsigned_integer<_Tp>::value, _Tp> +floor2(_Tp __t) noexcept +{ + return __t == 0 ? 0 : _Tp{1} << __bit_log2(__t); +} + +template <class _Tp> +_LIBCPP_INLINE_VISIBILITY constexpr +enable_if_t<__bitop_unsigned_integer<_Tp>::value, _Tp> +ceil2(_Tp __t) noexcept +{ + if (__t < 2) return 1; + const unsigned __n = numeric_limits<_Tp>::digits - countl_zero((_Tp)(__t - 1u)); + _LIBCPP_DEBUG_ASSERT(__libcpp_is_constant_evaluated() || __n != numeric_limits<_Tp>::digits, "Bad input to ceil2"); + + if constexpr (sizeof(_Tp) >= sizeof(unsigned)) + return _Tp{1} << __n; + else + { + const unsigned __extra = numeric_limits<unsigned>::digits - numeric_limits<_Tp>::digits; + const unsigned __retVal = 1u << (__n + __extra); + return (_Tp) (__retVal >> __extra); + } +} + +template <class _Tp> +_LIBCPP_INLINE_VISIBILITY constexpr +enable_if_t<__bitop_unsigned_integer<_Tp>::value, _Tp> +log2p1(_Tp __t) noexcept +{ + return __t == 0 ? 0 : __bit_log2(__t) + 1; +} + + +enum class endian +{ + little = 0xDEAD, + big = 0xFACE, +#if defined(_LIBCPP_LITTLE_ENDIAN) + native = little +#elif defined(_LIBCPP_BIG_ENDIAN) + native = big +#else + native = 0xCAFE +#endif +}; + +#endif // _LIBCPP_STD_VER > 17 + +_LIBCPP_END_NAMESPACE_STD + +_LIBCPP_POP_MACROS + +#endif // _LIBCPP_BIT |