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
| ; RUN: llc -mtriple armv7a--none-eabi < %s | FileCheck %s --check-prefix=CHECK --check-prefix=DISABLED
; RUN: llc -mtriple armv7a--none-eabi < %s -enable-ipra | FileCheck %s --check-prefix=CHECK --check-prefix=ENABLED
define void @leaf() {
entry:
tail call void asm sideeffect "", ""()
ret void
}
define void @leaf_r3() {
entry:
tail call void asm sideeffect "", "~{r3}"()
ret void
}
define void @leaf_r4() {
entry:
tail call void asm sideeffect "", "~{r4}"()
ret void
}
define void @leaf_s0() {
entry:
tail call void asm sideeffect "", "~{s0}"()
ret void
}
define void @leaf_d0() {
entry:
tail call void asm sideeffect "", "~{d0}"()
ret void
}
; r3 is normally caller-saved, but with IPRA we can see that it isn't used in
; the callee, so can leave a live value in it.
define void @test_r3_presrved() {
; CHECK-LABEL: test_r3_presrved:
entry:
; CHECK: ASM1: r3
; DISABLED: mov [[TEMP:r[0-9]+]], r3
; ENABLED-NOT: r3
; CHECK: bl leaf
; DISABLED: mov r3, [[TEMP]]
; ENABLED-NOT: r3
; CHECK: ASM2: r3
%a = tail call i32 asm sideeffect "// ASM1: $0", "={r3},0"(i32 undef)
tail call void @leaf()
%b = tail call i32 asm sideeffect "// ASM2: $0", "={r3},0"(i32 %a)
ret void
}
; Same as above, but r3 is clobbered in the callee, so it is clobbered by the
; call as normal.
define void @test_r3_clobbered() {
; CHECK-LABEL: test_r3_clobbered:
entry:
; CHECK: ASM1: r3
; CHECK: mov [[TEMP:r[0-9]+]], r3
; CHECK: bl leaf
; CHECK: mov r3, [[TEMP]]
; CHECK: ASM2: r3
%a = tail call i32 asm sideeffect "// ASM1: $0", "={r3},0"(i32 undef)
tail call void @leaf_r3()
%b = tail call i32 asm sideeffect "// ASM2: $0", "={r3},0"(i32 %a)
ret void
}
; r4 is a callee-saved register, so IPRA has no effect.
define void @test_r4_preserved() {
; CHECK-LABEL: test_r4_preserved:
entry:
; CHECK: ASM1: r4
; CHECK-NOT: r4
; CHECK: bl leaf
; CHECK-NOT: r4
; CHECK: ASM2: r4
%a = tail call i32 asm sideeffect "// ASM1: $0", "={r4},0"(i32 undef)
tail call void @leaf()
%b = tail call i32 asm sideeffect "// ASM2: $0", "={r4},0"(i32 %a)
ret void
}
define void @test_r4_clobbered() {
; CHECK-LABEL: test_r4_clobbered:
entry:
; CHECK: ASM1: r4
; CHECK-NOT: r4
; CHECK: bl leaf_r4
; CHECK-NOT: r4
; CHECK: ASM2: r4
%a = tail call i32 asm sideeffect "// ASM1: $0", "={r4},0"(i32 undef)
tail call void @leaf_r4()
%b = tail call i32 asm sideeffect "// ASM2: $0", "={r4},0"(i32 %a)
ret void
}
; r12 is the intra-call scratch register, so we have to assume it is clobbered
; even if we can see that the callee does not touch it.
define void @test_r12() {
; CHECK-LABEL: test_r12:
entry:
; CHECK: ASM1: r12
; CHECK: mov [[TEMP:r[0-9]+]], r12
; CHECK: bl leaf
; CHECK: mov r12, [[TEMP]]
; CHECK: ASM2: r12
%a = tail call i32 asm sideeffect "// ASM1: $0", "={r12},0"(i32 undef)
tail call void @leaf()
%b = tail call i32 asm sideeffect "// ASM2: $0", "={r12},0"(i32 %a)
ret void
}
; s0 and d0 are caller-saved, IPRA allows us to keep them live in the caller if
; the callee doesn't modify them.
define void @test_s0_preserved() {
; CHECK-LABEL: test_s0_preserved:
entry:
; CHECK: ASM1: s0
; DISABLED: vmov.f32 [[TEMP:s[0-9]+]], s0
; ENABLED-NOT: s0
; CHECK: bl leaf
; DISABLED: vmov.f32 s0, [[TEMP]]
; ENABLED-NOT: s0
; CHECK: ASM2: s0
%a = tail call float asm sideeffect "// ASM1: $0", "={s0},0"(float undef)
tail call void @leaf()
%b = tail call float asm sideeffect "// ASM2: $0", "={s0},0"(float %a)
ret void
}
define void @test_s0_clobbered() {
; CHECK-LABEL: test_s0_clobbered:
entry:
; CHECK: ASM1: s0
; CHECK: vmov.f32 [[TEMP:s[0-9]+]], s0
; CHECK: bl leaf_s0
; CHECK: vmov.f32 s0, [[TEMP]]
; CHECK: ASM2: s0
%a = tail call float asm sideeffect "// ASM1: $0", "={s0},0"(float undef)
tail call void @leaf_s0()
%b = tail call float asm sideeffect "// ASM2: $0", "={s0},0"(float %a)
ret void
}
define void @test_d0_preserved() {
; CHECK-LABEL: test_d0_preserved:
entry:
; CHECK: ASM1: d0
; DISABLED: vmov.f64 [[TEMP:d[0-9]+]], d0
; ENABLED-NOT: d0
; CHECK: bl leaf
; DISABLED: vmov.f64 d0, [[TEMP]]
; ENABLED-NOT: d0
; CHECK: ASM2: d0
%a = tail call double asm sideeffect "// ASM1: $0", "={d0},0"(double undef)
tail call void @leaf()
%b = tail call double asm sideeffect "// ASM2: $0", "={d0},0"(double %a)
ret void
}
define void @test_d0_clobbered() {
; CHECK-LABEL: test_d0_clobbered:
entry:
; CHECK: ASM1: d0
; CHECK: vmov.f64 [[TEMP:d[0-9]+]], d0
; CHECK: bl leaf_d0
; CHECK: vmov.f64 d0, [[TEMP]]
; CHECK: ASM2: d0
%a = tail call double asm sideeffect "// ASM1: $0", "={d0},0"(double undef)
tail call void @leaf_d0()
%b = tail call double asm sideeffect "// ASM2: $0", "={d0},0"(double %a)
ret void
}
; s0 and d0 overlap, so clobbering one in the callee prevents the other from
; being kept live across the call.
define void @test_s0_clobber_d0() {
; CHECK-LABEL: test_s0_clobber_d0:
entry:
; CHECK: ASM1: s0
; CHECK: vmov.f32 [[TEMP:s[0-9]+]], s0
; CHECK: bl leaf_d0
; CHECK: vmov.f32 s0, [[TEMP]]
; CHECK: ASM2: s0
%a = tail call float asm sideeffect "// ASM1: $0", "={s0},0"(float undef)
tail call void @leaf_d0()
%b = tail call float asm sideeffect "// ASM2: $0", "={s0},0"(float %a)
ret void
}
define void @test_d0_clobber_s0() {
; CHECK-LABEL: test_d0_clobber_s0:
entry:
; CHECK: ASM1: d0
; CHECK: vmov.f64 [[TEMP:d[0-9]+]], d0
; CHECK: bl leaf_s0
; CHECK: vmov.f64 d0, [[TEMP]]
; CHECK: ASM2: d0
%a = tail call double asm sideeffect "// ASM1: $0", "={d0},0"(double undef)
tail call void @leaf_s0()
%b = tail call double asm sideeffect "// ASM2: $0", "={d0},0"(double %a)
ret void
}
|