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1//===-- A self contained equivalent of std::limits --------------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_LIMITS_H10#define LLVM_LIBC_SRC___SUPPORT_CPP_LIMITS_H11 12#include "hdr/limits_macros.h" // CHAR_BIT13#include "src/__support/CPP/type_traits/is_integral.h"14#include "src/__support/CPP/type_traits/is_signed.h"15#include "src/__support/macros/attributes.h" // LIBC_INLINE16#include "src/__support/macros/config.h"17#include "src/__support/macros/properties/types.h" // LIBC_TYPES_HAS_INT12818 19namespace LIBC_NAMESPACE_DECL {20namespace cpp {21 22namespace internal {23 24template <typename T, T min_value, T max_value> struct integer_impl {25 static_assert(cpp::is_integral_v<T>);26 LIBC_INLINE static constexpr T max() { return max_value; }27 LIBC_INLINE static constexpr T min() { return min_value; }28 LIBC_INLINE_VAR static constexpr int digits =29 CHAR_BIT * sizeof(T) - cpp::is_signed_v<T>;30};31 32} // namespace internal33 34template <class T> struct numeric_limits {};35 36// TODO: Add numeric_limits specializations as needed for new types.37template <>38struct numeric_limits<short>39 : public internal::integer_impl<short, SHRT_MIN, SHRT_MAX> {};40 41template <>42struct numeric_limits<unsigned short>43 : public internal::integer_impl<unsigned short, 0, USHRT_MAX> {};44 45template <>46struct numeric_limits<int>47 : public internal::integer_impl<int, INT_MIN, INT_MAX> {};48 49template <>50struct numeric_limits<unsigned int>51 : public internal::integer_impl<unsigned int, 0, UINT_MAX> {};52 53template <>54struct numeric_limits<long>55 : public internal::integer_impl<long, LONG_MIN, LONG_MAX> {};56 57template <>58struct numeric_limits<unsigned long>59 : public internal::integer_impl<unsigned long, 0, ULONG_MAX> {};60 61template <>62struct numeric_limits<long long>63 : public internal::integer_impl<long long, LLONG_MIN, LLONG_MAX> {};64 65template <>66struct numeric_limits<unsigned long long>67 : public internal::integer_impl<unsigned long long, 0, ULLONG_MAX> {};68 69template <>70struct numeric_limits<char>71 : public internal::integer_impl<char, CHAR_MIN, CHAR_MAX> {};72 73template <>74struct numeric_limits<signed char>75 : public internal::integer_impl<signed char, SCHAR_MIN, SCHAR_MAX> {};76 77template <>78struct numeric_limits<unsigned char>79 : public internal::integer_impl<unsigned char, 0, UCHAR_MAX> {};80 81#ifdef LIBC_TYPES_HAS_INT12882// On platform where UInt128 resolves to __uint128_t, this specialization83// provides the limits of UInt128.84template <>85struct numeric_limits<__uint128_t>86 : public internal::integer_impl<__uint128_t, 0, ~__uint128_t(0)> {};87#endif88 89} // namespace cpp90} // namespace LIBC_NAMESPACE_DECL91 92#endif // LLVM_LIBC_SRC___SUPPORT_CPP_LIMITS_H93