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
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
|
// RUN: %clang_cc1 -std=c++2a -verify %s -fcxx-exceptions -triple=x86_64-linux-gnu
#include "Inputs/std-compare.h"
namespace ThreeWayComparison {
struct A {
int n;
constexpr friend int operator<=>(const A &a, const A &b) {
return a.n < b.n ? -1 : a.n > b.n ? 1 : 0;
}
};
static_assert(A{1} <=> A{2} < 0);
static_assert(A{2} <=> A{1} > 0);
static_assert(A{2} <=> A{2} == 0);
static_assert(1 <=> 2 < 0);
static_assert(2 <=> 1 > 0);
static_assert(1 <=> 1 == 0);
constexpr int k = (1 <=> 1, 0);
// expected-warning@-1 {{three-way comparison result unused}}
static_assert(std::strong_ordering::equal == 0);
constexpr void f() {
void(1 <=> 1);
}
struct MemPtr {
void foo() {}
void bar() {}
int data;
int data2;
long data3;
};
struct MemPtr2 {
void foo() {}
void bar() {}
int data;
int data2;
long data3;
};
using MemPtrT = void (MemPtr::*)();
using FnPtrT = void (*)();
void FnPtr1() {}
void FnPtr2() {}
#define CHECK(...) ((__VA_ARGS__) ? void() : throw "error")
#define CHECK_TYPE(...) static_assert(__is_same(__VA_ARGS__));
constexpr bool test_constexpr_success = [] {
{
auto &EQ = std::strong_ordering::equal;
auto &LESS = std::strong_ordering::less;
auto &GREATER = std::strong_ordering::greater;
using SO = std::strong_ordering;
auto eq = (42 <=> 42);
CHECK_TYPE(decltype(eq), SO);
CHECK(eq.test_eq(EQ));
auto less = (-1 <=> 0);
CHECK_TYPE(decltype(less), SO);
CHECK(less.test_eq(LESS));
auto greater = (42l <=> 1u);
CHECK_TYPE(decltype(greater), SO);
CHECK(greater.test_eq(GREATER));
}
{
using PO = std::partial_ordering;
auto EQUIV = PO::equivalent;
auto LESS = PO::less;
auto GREATER = PO::greater;
auto eq = (42.0 <=> 42.0);
CHECK_TYPE(decltype(eq), PO);
CHECK(eq.test_eq(EQUIV));
auto less = (39.0 <=> 42.0);
CHECK_TYPE(decltype(less), PO);
CHECK(less.test_eq(LESS));
auto greater = (-10.123 <=> -101.1);
CHECK_TYPE(decltype(greater), PO);
CHECK(greater.test_eq(GREATER));
}
{
using SE = std::strong_equality;
auto EQ = SE::equal;
auto NEQ = SE::nonequal;
MemPtrT P1 = &MemPtr::foo;
MemPtrT P12 = &MemPtr::foo;
MemPtrT P2 = &MemPtr::bar;
MemPtrT P3 = nullptr;
auto eq = (P1 <=> P12);
CHECK_TYPE(decltype(eq), SE);
CHECK(eq.test_eq(EQ));
auto neq = (P1 <=> P2);
CHECK_TYPE(decltype(eq), SE);
CHECK(neq.test_eq(NEQ));
auto eq2 = (P3 <=> nullptr);
CHECK_TYPE(decltype(eq2), SE);
CHECK(eq2.test_eq(EQ));
}
{
using SE = std::strong_equality;
auto EQ = SE::equal;
auto NEQ = SE::nonequal;
FnPtrT F1 = &FnPtr1;
FnPtrT F12 = &FnPtr1;
FnPtrT F2 = &FnPtr2;
FnPtrT F3 = nullptr;
auto eq = (F1 <=> F12);
CHECK_TYPE(decltype(eq), SE);
CHECK(eq.test_eq(EQ));
auto neq = (F1 <=> F2);
CHECK_TYPE(decltype(neq), SE);
CHECK(neq.test_eq(NEQ));
}
{ // mixed nullptr tests
using SO = std::strong_ordering;
using SE = std::strong_equality;
int x = 42;
int *xp = &x;
MemPtrT mf = nullptr;
MemPtrT mf2 = &MemPtr::foo;
auto r3 = (mf <=> nullptr);
CHECK_TYPE(decltype(r3), std::strong_equality);
CHECK(r3.test_eq(SE::equal));
}
return true;
}();
template <auto LHS, auto RHS, bool ExpectTrue = false>
constexpr bool test_constexpr() {
using nullptr_t = decltype(nullptr);
using LHSTy = decltype(LHS);
using RHSTy = decltype(RHS);
// expected-note@+1 {{subexpression not valid in a constant expression}}
auto Res = (LHS <=> RHS);
if constexpr (__is_same(LHSTy, nullptr_t) || __is_same(RHSTy, nullptr_t)) {
CHECK_TYPE(decltype(Res), std::strong_equality);
}
if (ExpectTrue)
return Res == 0;
return Res != 0;
}
int dummy = 42;
int dummy2 = 101;
constexpr bool tc1 = test_constexpr<nullptr, &dummy>();
constexpr bool tc2 = test_constexpr<&dummy, nullptr>();
// OK, equality comparison only
constexpr bool tc3 = test_constexpr<&MemPtr::foo, nullptr>();
constexpr bool tc4 = test_constexpr<nullptr, &MemPtr::foo>();
constexpr bool tc5 = test_constexpr<&MemPtr::foo, &MemPtr::bar>();
constexpr bool tc6 = test_constexpr<&MemPtr::data, nullptr>();
constexpr bool tc7 = test_constexpr<nullptr, &MemPtr::data>();
constexpr bool tc8 = test_constexpr<&MemPtr::data, &MemPtr::data2>();
// expected-error@+1 {{must be initialized by a constant expression}}
constexpr bool tc9 = test_constexpr<&dummy, &dummy2>(); // expected-note {{in call}}
template <class T, class R, class I>
constexpr T makeComplex(R r, I i) {
T res{r, i};
return res;
};
template <class T, class ResultT>
constexpr bool complex_test(T x, T y, ResultT Expect) {
auto res = x <=> y;
CHECK_TYPE(decltype(res), ResultT);
return res.test_eq(Expect);
}
static_assert(complex_test(makeComplex<_Complex double>(0.0, 0.0),
makeComplex<_Complex double>(0.0, 0.0),
std::weak_equality::equivalent));
static_assert(complex_test(makeComplex<_Complex double>(0.0, 0.0),
makeComplex<_Complex double>(1.0, 0.0),
std::weak_equality::nonequivalent));
static_assert(complex_test(makeComplex<_Complex double>(0.0, 0.0),
makeComplex<_Complex double>(0.0, 1.0),
std::weak_equality::nonequivalent));
static_assert(complex_test(makeComplex<_Complex int>(0, 0),
makeComplex<_Complex int>(0, 0),
std::strong_equality::equal));
static_assert(complex_test(makeComplex<_Complex int>(0, 0),
makeComplex<_Complex int>(1, 0),
std::strong_equality::nonequal));
// TODO: defaulted operator <=>
} // namespace ThreeWayComparison
|
