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
|
#![feature(custom_mir, core_intrinsics)]
extern crate core;
use core::intrinsics::mir::*;
// EMIT_MIR enums.switch_bool.built.after.mir
#[custom_mir(dialect = "built")]
pub fn switch_bool(b: bool) -> u32 {
mir!(
{
match b {
true => t,
false => f,
_ => f,
}
}
t = {
RET = 5;
Return()
}
f = {
RET = 10;
Return()
}
)
}
// EMIT_MIR enums.switch_option.built.after.mir
#[custom_mir(dialect = "built")]
pub fn switch_option(option: Option<()>) -> bool {
mir!(
{
let discr = Discriminant(option);
match discr {
0 => n,
1 => s,
_ => s,
}
}
n = {
RET = false;
Return()
}
s = {
RET = true;
Return()
}
)
}
#[repr(u8)]
enum Bool {
False = 0,
True = 1,
}
// EMIT_MIR enums.switch_option_repr.built.after.mir
#[custom_mir(dialect = "built")]
fn switch_option_repr(option: Bool) -> bool {
mir!(
{
let discr = Discriminant(option);
match discr {
0 => f,
_ => t,
}
}
t = {
RET = true;
Return()
}
f = {
RET = false;
Return()
}
)
}
// EMIT_MIR enums.set_discr.built.after.mir
#[custom_mir(dialect = "runtime", phase = "initial")]
fn set_discr(option: &mut Option<()>) {
mir!({
Deinit(*option);
SetDiscriminant(*option, 0);
Return()
})
}
// EMIT_MIR enums.set_discr_repr.built.after.mir
#[custom_mir(dialect = "runtime", phase = "initial")]
fn set_discr_repr(b: &mut Bool) {
mir!({
SetDiscriminant(*b, 0);
Return()
})
}
fn main() {
assert_eq!(switch_bool(true), 5);
assert_eq!(switch_bool(false), 10);
assert_eq!(switch_option(Some(())), true);
assert_eq!(switch_option(None), false);
assert_eq!(switch_option_repr(Bool::True), true);
assert_eq!(switch_option_repr(Bool::False), false);
let mut opt = Some(());
set_discr(&mut opt);
assert_eq!(opt, None);
let mut b = Bool::True;
set_discr_repr(&mut b);
assert!(matches!(b, Bool::False));
}
|
