1 // -*- C++ -*- C library enhancements header.
2
3 // Copyright (C) 2016-2023 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24
25 /** @file include/bits/std_abs.h
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{cmath, cstdlib}
28 */
29
30 #ifndef _GLIBCXX_BITS_STD_ABS_H
31 #define _GLIBCXX_BITS_STD_ABS_H
32
33 #pragma GCC system_header
34
35 #include <bits/c++config.h>
36
37 #define _GLIBCXX_INCLUDE_NEXT_C_HEADERS
38 #include_next <stdlib.h>
39 #ifdef __CORRECT_ISO_CPP_MATH_H_PROTO
40 # include_next <math.h>
41 #endif
42 #undef _GLIBCXX_INCLUDE_NEXT_C_HEADERS
43
44 #undef abs
45
46 extern "C++"
47 {
48 namespace std _GLIBCXX_VISIBILITY(default)
49 {
50 _GLIBCXX_BEGIN_NAMESPACE_VERSION
51
52 using ::abs;
53
54 #ifndef __CORRECT_ISO_CPP_STDLIB_H_PROTO
55 inline long
56 abs(long __i) { return __builtin_labs(__i); }
57 #endif
58
59 #ifdef _GLIBCXX_USE_LONG_LONG
60 inline long long
61 abs(long long __x) { return __builtin_llabs (__x); }
62 #endif
63
64 // _GLIBCXX_RESOLVE_LIB_DEFECTS
65 // 2192. Validity and return type of std::abs(0u) is unclear
66 // 2294. <cstdlib> should declare abs(double)
67 // 2735. std::abs(short), std::abs(signed char) and others should return int
68
69 #ifndef __CORRECT_ISO_CPP_MATH_H_PROTO
70 inline _GLIBCXX_CONSTEXPR double
71 abs(double __x)
72 { return __builtin_fabs(__x); }
73
74 inline _GLIBCXX_CONSTEXPR float
75 abs(float __x)
76 { return __builtin_fabsf(__x); }
77
78 inline _GLIBCXX_CONSTEXPR long double
79 abs(long double __x)
80 { return __builtin_fabsl(__x); }
81 #endif
82
83 #if defined(__GLIBCXX_TYPE_INT_N_0)
84 __extension__ inline _GLIBCXX_CONSTEXPR __GLIBCXX_TYPE_INT_N_0
85 abs(__GLIBCXX_TYPE_INT_N_0 __x) { return __x >= 0 ? __x : -__x; }
86 #endif
87 #if defined(__GLIBCXX_TYPE_INT_N_1)
88 __extension__ inline _GLIBCXX_CONSTEXPR __GLIBCXX_TYPE_INT_N_1
89 abs(__GLIBCXX_TYPE_INT_N_1 __x) { return __x >= 0 ? __x : -__x; }
90 #endif
91 #if defined(__GLIBCXX_TYPE_INT_N_2)
92 __extension__ inline _GLIBCXX_CONSTEXPR __GLIBCXX_TYPE_INT_N_2
93 abs(__GLIBCXX_TYPE_INT_N_2 __x) { return __x >= 0 ? __x : -__x; }
94 #endif
95 #if defined(__GLIBCXX_TYPE_INT_N_3)
96 __extension__ inline _GLIBCXX_CONSTEXPR __GLIBCXX_TYPE_INT_N_3
97 abs(__GLIBCXX_TYPE_INT_N_3 __x) { return __x >= 0 ? __x : -__x; }
98 #endif
99
100 #if defined(__STDCPP_FLOAT16_T__) && defined(_GLIBCXX_FLOAT_IS_IEEE_BINARY32)
101 constexpr _Float16
102 abs(_Float16 __x)
103 { return _Float16(__builtin_fabsf(__x)); }
104 #endif
105
106 #if defined(__STDCPP_FLOAT32_T__) && defined(_GLIBCXX_FLOAT_IS_IEEE_BINARY32)
107 constexpr _Float32
108 abs(_Float32 __x)
109 { return __builtin_fabsf(__x); }
110 #endif
111
112 #if defined(__STDCPP_FLOAT64_T__) && defined(_GLIBCXX_DOUBLE_IS_IEEE_BINARY64)
113 constexpr _Float64
114 abs(_Float64 __x)
115 { return __builtin_fabs(__x); }
116 #endif
117
118 #if defined(__STDCPP_FLOAT128_T__) && defined(_GLIBCXX_LDOUBLE_IS_IEEE_BINARY128)
119 constexpr _Float128
120 abs(_Float128 __x)
121 { return __builtin_fabsl(__x); }
122 #elif defined(__STDCPP_FLOAT128_T__) && defined(_GLIBCXX_HAVE_FLOAT128_MATH)
123 constexpr _Float128
124 abs(_Float128 __x)
125 { return __builtin_fabsf128(__x); }
126 #endif
127
128 #if defined(__STDCPP_BFLOAT16_T__) && defined(_GLIBCXX_FLOAT_IS_IEEE_BINARY32)
129 constexpr __gnu_cxx::__bfloat16_t
130 abs(__gnu_cxx::__bfloat16_t __x)
131 { return __gnu_cxx::__bfloat16_t(__builtin_fabsf(__x)); }
132 #endif
133
134 #if !defined(__STRICT_ANSI__) && defined(_GLIBCXX_USE_FLOAT128)
135 __extension__ inline _GLIBCXX_CONSTEXPR
136 __float128
137 abs(__float128 __x)
138 {
139 #if defined(_GLIBCXX_LDOUBLE_IS_IEEE_BINARY128)
140 return __builtin_fabsl(__x);
141 #elif defined(_GLIBCXX_HAVE_FLOAT128_MATH)
142 return __builtin_fabsf128(__x);
143 #else
144 // Assume that __builtin_signbit works for __float128.
145 return __builtin_signbit(__x) ? -__x : __x;
146 #endif
147 }
148 #endif
149
150 _GLIBCXX_END_NAMESPACE_VERSION
151 } // namespace
152 } // extern "C++"
153
154 #endif // _GLIBCXX_BITS_STD_ABS_H