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
|
#pragma once
#include "compat/assert.hpp"
#include <type_traits>
#include <tuple>
#include <concepts>
namespace floormat::detail_Pack_output {
template<size_t N>
struct output_bits final
{
static_assert(N > 0);
static_assert(N < sizeof(size_t)*8);
static constexpr size_t length = N;
};
template<std::unsigned_integral T, size_t CAPACITY>
struct output
{
static_assert(std::is_fundamental_v<T>);
static_assert(CAPACITY <= sizeof(T)*8);
static constexpr size_t Capacity = CAPACITY;
T value{0};
};
template<typename T, size_t LENGTH>
struct output_field
{
T value;
static constexpr size_t Length = LENGTH;
};
template<std::unsigned_integral Type, typename Tuple> struct count_bits_;
template<std::unsigned_integral Int, size_t N, typename... Ts>
struct count_bits_<Int, std::tuple<output_field<Int, N>, Ts...>>
{
static constexpr size_t length = N + count_bits_<Int, std::tuple<Ts...>>::length;
static_assert(length <= sizeof(Int)*8);
};
template<std::unsigned_integral Int> struct count_bits_<Int, std::tuple<>>
{
static constexpr size_t length = 0;
};
template<typename T, typename Tuple> constexpr inline size_t count_bits = count_bits_<T, Tuple>::length;
template <std::size_t ... Is>
constexpr std::index_sequence<sizeof...(Is)-1uz-Is...> reverse_index_sequence(std::index_sequence<Is...> const&);
template <std::size_t N>
using make_reverse_index_sequence = decltype(reverse_index_sequence(std::make_index_sequence<N>{}));
template<typename T, size_t Capacity, size_t Left, size_t I, size_t... Is, typename Tuple>
constexpr T write_(const Tuple& tuple, output<T, Left> st, output_bits<Capacity>, std::index_sequence<I, Is...>)
{
static_assert(Capacity <= sizeof(T)*8);
static_assert(Left <= Capacity);
constexpr size_t N = std::tuple_element_t<I, Tuple>::Length;
static_assert(N <= Left);
T x = std::get<I>(tuple).value;
T value = T(T(st.value << N) | x);
return write_(tuple, output<T, Left - N>{value}, output_bits<Capacity>{}, std::index_sequence<Is...>{});
}
template<typename T, size_t Capacity, size_t Left, typename Tuple>
constexpr T write_(const Tuple&, output<T, Left> st, output_bits<Capacity>, std::index_sequence<>)
{
return st.value;
}
} // namespace floormat::detail_Pack_output
|
