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
|
//@ compile-flags: -O -Z merge-functions=disabled
//@ only-x86_64
#![crate_type = "lib"]
use std::mem::swap;
type RGB48 = [u16; 3];
// CHECK-LABEL: @swap_rgb48_manually(
#[no_mangle]
pub fn swap_rgb48_manually(x: &mut RGB48, y: &mut RGB48) {
// FIXME: See #115212 for why this has an alloca again
// CHECK: alloca [6 x i8], align 2
// CHECK: call void @llvm.memcpy.p0.p0.i64({{.+}}, i64 6, i1 false)
// CHECK: call void @llvm.memcpy.p0.p0.i64({{.+}}, i64 6, i1 false)
// CHECK: call void @llvm.memcpy.p0.p0.i64({{.+}}, i64 6, i1 false)
let temp = *x;
*x = *y;
*y = temp;
}
// CHECK-LABEL: @swap_rgb48
#[no_mangle]
pub fn swap_rgb48(x: &mut RGB48, y: &mut RGB48) {
// CHECK-NOT: alloca
// Whether `i8` is the best for this is unclear, but
// might as well record what's actually happening right now.
// CHECK: load i8
// CHECK: load i8
// CHECK: store i8
// CHECK: store i8
swap(x, y)
}
type RGBA64 = [u16; 4];
// CHECK-LABEL: @swap_rgba64
#[no_mangle]
pub fn swap_rgba64(x: &mut RGBA64, y: &mut RGBA64) {
// CHECK-NOT: alloca
// CHECK-DAG: %[[XVAL:.+]] = load i64, ptr %x, align 2
// CHECK-DAG: %[[YVAL:.+]] = load i64, ptr %y, align 2
// CHECK-DAG: store i64 %[[YVAL]], ptr %x, align 2
// CHECK-DAG: store i64 %[[XVAL]], ptr %y, align 2
swap(x, y)
}
// CHECK-LABEL: @swap_vecs
#[no_mangle]
pub fn swap_vecs(x: &mut Vec<u32>, y: &mut Vec<u32>) {
// CHECK-NOT: alloca
// There are plenty more loads and stores than just these,
// but at least one sure better be 64-bit (for size or capacity).
// CHECK: load i64
// CHECK: load i64
// CHECK: store i64
// CHECK: store i64
// CHECK: ret void
swap(x, y)
}
// CHECK-LABEL: @swap_slices
#[no_mangle]
pub fn swap_slices<'a>(x: &mut &'a [u32], y: &mut &'a [u32]) {
// CHECK-NOT: alloca
// CHECK: load ptr
// CHECK: load i64
// CHECK: call void @llvm.memcpy.p0.p0.i64({{.+}}, i64 16, i1 false)
// CHECK: store ptr
// CHECK: store i64
swap(x, y)
}
// LLVM doesn't vectorize a loop over 3-byte elements,
// so we chunk it down to bytes and loop over those instead.
type RGB24 = [u8; 3];
// CHECK-LABEL: @swap_rgb24_slices
#[no_mangle]
pub fn swap_rgb24_slices(x: &mut [RGB24], y: &mut [RGB24]) {
// CHECK-NOT: alloca
// CHECK: load <{{[0-9]+}} x i8>
// CHECK: store <{{[0-9]+}} x i8>
if x.len() == y.len() {
x.swap_with_slice(y);
}
}
// This one has a power-of-two size, so we iterate over it directly
type RGBA32 = [u8; 4];
// CHECK-LABEL: @swap_rgba32_slices
#[no_mangle]
pub fn swap_rgba32_slices(x: &mut [RGBA32], y: &mut [RGBA32]) {
// CHECK-NOT: alloca
// CHECK: load <{{[0-9]+}} x i32>
// CHECK: store <{{[0-9]+}} x i32>
if x.len() == y.len() {
x.swap_with_slice(y);
}
}
// Strings have a non-power-of-two size, but have pointer alignment,
// so we swap usizes instead of dropping all the way down to bytes.
const _: () = assert!(!std::mem::size_of::<String>().is_power_of_two());
// CHECK-LABEL: @swap_string_slices
#[no_mangle]
pub fn swap_string_slices(x: &mut [String], y: &mut [String]) {
// CHECK-NOT: alloca
// CHECK: load <{{[0-9]+}} x i64>
// CHECK: store <{{[0-9]+}} x i64>
if x.len() == y.len() {
x.swap_with_slice(y);
}
}
#[repr(C, packed)]
pub struct Packed {
pub first: bool,
pub second: usize,
}
// CHECK-LABEL: @swap_packed_structs
#[no_mangle]
pub fn swap_packed_structs(x: &mut Packed, y: &mut Packed) {
// CHECK-NOT: alloca
// CHECK: ret void
swap(x, y)
}
|
