arm64-memset-to-bzero.ll
3.47 KB
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
; RUN: llc %s -enable-machine-outliner=never -mtriple=arm64-apple-darwin -o - \
; RUN: | FileCheck --check-prefixes=CHECK,CHECK-DARWIN %s
; RUN: llc %s -enable-machine-outliner=never -mtriple=arm64-linux-gnu -o - | \
; RUN: FileCheck --check-prefixes=CHECK,CHECK-LINUX %s
; <rdar://problem/14199482> ARM64: Calls to bzero() replaced with calls to memset()
; CHECK-LABEL: fct1:
; For small size (<= 256), we do not change memset to bzero.
; CHECK-DARWIN: {{b|bl}} _memset
; CHECK-LINUX: {{b|bl}} memset
define void @fct1(i8* nocapture %ptr) minsize {
entry:
tail call void @llvm.memset.p0i8.i64(i8* %ptr, i8 0, i64 256, i1 false)
ret void
}
declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i1)
; CHECK-LABEL: fct2:
; When the size is bigger than 256, change into bzero.
; CHECK-DARWIN: {{b|bl}} _bzero
; CHECK-LINUX: {{b|bl}} memset
define void @fct2(i8* nocapture %ptr) minsize {
entry:
tail call void @llvm.memset.p0i8.i64(i8* %ptr, i8 0, i64 257, i1 false)
ret void
}
; CHECK-LABEL: fct3:
; For unknown size, change to bzero.
; CHECK-DARWIN: {{b|bl}} _bzero
; CHECK-LINUX: {{b|bl}} memset
define void @fct3(i8* nocapture %ptr, i32 %unknown) minsize {
entry:
%conv = sext i32 %unknown to i64
tail call void @llvm.memset.p0i8.i64(i8* %ptr, i8 0, i64 %conv, i1 false)
ret void
}
; CHECK-LABEL: fct4:
; Size <= 256, no change.
; CHECK-DARWIN: {{b|bl}} _memset
; CHECK-LINUX: {{b|bl}} memset
define void @fct4(i8* %ptr) minsize {
entry:
%tmp = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
%call = tail call i8* @__memset_chk(i8* %ptr, i32 0, i64 256, i64 %tmp)
ret void
}
declare i8* @__memset_chk(i8*, i32, i64, i64)
declare i64 @llvm.objectsize.i64(i8*, i1)
; CHECK-LABEL: fct5:
; Size > 256, change.
; CHECK-DARWIN: {{b|bl}} _bzero
; CHECK-LINUX: {{b|bl}} memset
define void @fct5(i8* %ptr) minsize {
entry:
%tmp = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
%call = tail call i8* @__memset_chk(i8* %ptr, i32 0, i64 257, i64 %tmp)
ret void
}
; CHECK-LABEL: fct6:
; Size = unknown, change.
; CHECK-DARWIN: {{b|bl}} _bzero
; CHECK-LINUX: {{b|bl}} memset
define void @fct6(i8* %ptr, i32 %unknown) minsize {
entry:
%conv = sext i32 %unknown to i64
%tmp = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
%call = tail call i8* @__memset_chk(i8* %ptr, i32 0, i64 %conv, i64 %tmp)
ret void
}
; Next functions check that memset is not turned into bzero
; when the set constant is non-zero, whatever the given size.
; CHECK-LABEL: fct7:
; memset with something that is not a zero, no change.
; CHECK-DARWIN: {{b|bl}} _memset
; CHECK-LINUX: {{b|bl}} memset
define void @fct7(i8* %ptr) minsize {
entry:
%tmp = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
%call = tail call i8* @__memset_chk(i8* %ptr, i32 1, i64 256, i64 %tmp)
ret void
}
; CHECK-LABEL: fct8:
; memset with something that is not a zero, no change.
; CHECK-DARWIN: {{b|bl}} _memset
; CHECK-LINUX: {{b|bl}} memset
define void @fct8(i8* %ptr) minsize {
entry:
%tmp = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
%call = tail call i8* @__memset_chk(i8* %ptr, i32 1, i64 257, i64 %tmp)
ret void
}
; CHECK-LABEL: fct9:
; memset with something that is not a zero, no change.
; CHECK-DARWIN: {{b|bl}} _memset
; CHECK-LINUX: {{b|bl}} memset
define void @fct9(i8* %ptr, i32 %unknown) minsize {
entry:
%conv = sext i32 %unknown to i64
%tmp = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
%call = tail call i8* @__memset_chk(i8* %ptr, i32 1, i64 %conv, i64 %tmp)
ret void
}