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-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLVM_LIBC_UTILS_CPP_LIMITS_H
10 #define LLVM_LIBC_UTILS_CPP_LIMITS_H
11 
12 #include <limits.h>
13 
14 namespace __llvm_libc {
15 namespace cpp {
16 
17 template <class T> class NumericLimits {
18 public:
19   static constexpr T max();
20   static constexpr T min();
21 };
22 
23 // TODO: Add NumericLimits specializations as needed for new types.
24 
25 template <> class NumericLimits<int> {
26 public:
max()27   static constexpr int max() { return INT_MAX; }
min()28   static constexpr int min() { return INT_MIN; }
29 };
30 template <> class NumericLimits<unsigned int> {
31 public:
max()32   static constexpr unsigned int max() { return UINT_MAX; }
min()33   static constexpr unsigned int min() { return 0; }
34 };
35 template <> class NumericLimits<long> {
36 public:
max()37   static constexpr long max() { return LONG_MAX; }
min()38   static constexpr long min() { return LONG_MIN; }
39 };
40 template <> class NumericLimits<unsigned long> {
41 public:
max()42   static constexpr unsigned long max() { return ULONG_MAX; }
min()43   static constexpr unsigned long min() { return 0; }
44 };
45 template <> class NumericLimits<long long> {
46 public:
max()47   static constexpr long long max() { return LLONG_MAX; }
min()48   static constexpr long long min() { return LLONG_MIN; }
49 };
50 template <> class NumericLimits<unsigned long long> {
51 public:
max()52   static constexpr unsigned long long max() { return ULLONG_MAX; }
min()53   static constexpr unsigned long long min() { return 0; }
54 };
55 template <> class NumericLimits<__uint128_t> {
56 public:
max()57   static constexpr __uint128_t max() { return ~__uint128_t(0); }
min()58   static constexpr __uint128_t min() { return 0; }
59 };
60 template <> class NumericLimits<__int128_t> {
61 public:
max()62   static constexpr __int128_t max() { return ~__uint128_t(0) >> 1; }
min()63   static constexpr __int128_t min() { return __int128_t(1) << 127; }
64 };
65 
66 } // namespace cpp
67 } // namespace __llvm_libc
68 
69 #endif // LLVM_LIBC_UTILS_CPP_LIMITS_H
70