1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
|
/*
* Copyright (C) 2023 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* License header from dragonbox
* https://github.com/jk-jeon/dragonbox/blob/master/LICENSE-Boost
* https://github.com/jk-jeon/dragonbox/blob/master/LICENSE-Apache2-LLVM
*/
#pragma once
#include <algorithm>
#include <wtf/dtoa/utils.h>
namespace WTF {
namespace dragonbox {
namespace detail {
////////////////////////////////////////////////////////////////////////////////////////
// Some basic features for encoding/decoding IEEE-754 formats.
////////////////////////////////////////////////////////////////////////////////////////
template<class T>
typename std::add_rvalue_reference<T>::type declval() noexcept;
template<class T>
struct physical_bits {
static constexpr size_t value = sizeof(T) * std::numeric_limits<unsigned char>::digits;
};
template<class T>
struct value_bits {
static constexpr size_t value = std::numeric_limits<typename std::enable_if<std::is_unsigned<T>::value, T>::type>::digits;
};
////////////////////////////////////////////////////////////////////////////////////////
// Some simple utilities for constexpr computation.
////////////////////////////////////////////////////////////////////////////////////////
template <int32_t k, class Int>
constexpr Int compute_power(Int a) noexcept {
static_assert(k >= 0, "");
Int p = 1;
for (int32_t i = 0; i < k; ++i)
p *= a;
return p;
}
template<int32_t a, class UInt>
constexpr int32_t count_factors(UInt n) noexcept
{
static_assert(a > 1, "");
int32_t c = 0;
while (!(n % a)) {
n /= a;
++c;
}
return c;
}
} // namespace detail
} // namespace dragonbox
} // namespace WTF
|
