aboutsummaryrefslogtreecommitdiffstats
path: root/test/Transforms/Inline/inline-tail.ll
blob: b40328e0a272ac6347e03254ccc59e5b60a2385a (plain)
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
; RUN: opt < %s -inline -S | FileCheck %s

; We have to apply the less restrictive TailCallKind of the call site being
; inlined and any call sites cloned into the caller.

; No tail marker after inlining, since test_capture_c captures an alloca.
; CHECK: define void @test_capture_a(
; CHECK-NOT: tail
; CHECK: call void @test_capture_c(

declare void @test_capture_c(i32*)
define internal void @test_capture_b(i32* %P) {
  tail call void @test_capture_c(i32* %P)
  ret void
}
define void @test_capture_a() {
  %A = alloca i32  		; captured by test_capture_b
  call void @test_capture_b(i32* %A)
  ret void
}

; No musttail marker after inlining, since the prototypes don't match.
; CHECK: define void @test_proto_mismatch_a(
; CHECK-NOT: musttail
; CHECK: call void @test_proto_mismatch_c(

declare void @test_proto_mismatch_c(i32*)
define internal void @test_proto_mismatch_b(i32* %p) {
  musttail call void @test_proto_mismatch_c(i32* %p)
  ret void
}
define void @test_proto_mismatch_a() {
  call void @test_proto_mismatch_b(i32* null)
  ret void
}

; After inlining through a musttail call site, we need to keep musttail markers
; to prevent unbounded stack growth.
; CHECK: define void @test_musttail_basic_a(
; CHECK: musttail call void @test_musttail_basic_c(

declare void @test_musttail_basic_c(i32* %p)
define internal void @test_musttail_basic_b(i32* %p) {
  musttail call void @test_musttail_basic_c(i32* %p)
  ret void
}
define void @test_musttail_basic_a(i32* %p) {
  musttail call void @test_musttail_basic_b(i32* %p)
  ret void
}

; Don't insert lifetime end markers here, the lifetime is trivially over due
; the return.
; CHECK: define void @test_byval_a(
; CHECK: musttail call void @test_byval_c(
; CHECK-NEXT: ret void

declare void @test_byval_c(i32* byval %p)
define internal void @test_byval_b(i32* byval %p) {
  musttail call void @test_byval_c(i32* byval %p)
  ret void
}
define void @test_byval_a(i32* byval %p) {
  musttail call void @test_byval_b(i32* byval %p)
  ret void
}

; Don't insert a stack restore, we're about to return.
; CHECK: define void @test_dynalloca_a(
; CHECK: call i8* @llvm.stacksave(
; CHECK: alloca i8, i32 %n
; CHECK: musttail call void @test_dynalloca_c(
; CHECK-NEXT: ret void

declare void @escape(i8* %buf)
declare void @test_dynalloca_c(i32* byval %p, i32 %n)
define internal void @test_dynalloca_b(i32* byval %p, i32 %n) alwaysinline {
  %buf = alloca i8, i32 %n              ; dynamic alloca
  call void @escape(i8* %buf)           ; escape it
  musttail call void @test_dynalloca_c(i32* byval %p, i32 %n)
  ret void
}
define void @test_dynalloca_a(i32* byval %p, i32 %n) {
  musttail call void @test_dynalloca_b(i32* byval %p, i32 %n)
  ret void
}

; We can't merge the returns.
; CHECK: define void @test_multiret_a(
; CHECK: musttail call void @test_multiret_c(
; CHECK-NEXT: ret void
; CHECK: musttail call void @test_multiret_d(
; CHECK-NEXT: ret void

declare void @test_multiret_c(i1 zeroext %b)
declare void @test_multiret_d(i1 zeroext %b)
define internal void @test_multiret_b(i1 zeroext %b) {
  br i1 %b, label %c, label %d
c:
  musttail call void @test_multiret_c(i1 zeroext %b)
  ret void
d:
  musttail call void @test_multiret_d(i1 zeroext %b)
  ret void
}
define void @test_multiret_a(i1 zeroext %b) {
  musttail call void @test_multiret_b(i1 zeroext %b)
  ret void
}

; We have to avoid bitcast chains.
; CHECK: define i32* @test_retptr_a(
; CHECK: musttail call i8* @test_retptr_c(
; CHECK-NEXT: bitcast i8* {{.*}} to i32*
; CHECK-NEXT: ret i32*

declare i8* @test_retptr_c()
define internal i16* @test_retptr_b() {
  %rv = musttail call i8* @test_retptr_c()
  %v = bitcast i8* %rv to i16*
  ret i16* %v
}
define i32* @test_retptr_a() {
  %rv = musttail call i16* @test_retptr_b()
  %v = bitcast i16* %rv to i32*
  ret i32* %v
}

; Combine the last two cases: multiple returns with pointer bitcasts.
; CHECK: define i32* @test_multiptrret_a(
; CHECK: musttail call i8* @test_multiptrret_c(
; CHECK-NEXT: bitcast i8* {{.*}} to i32*
; CHECK-NEXT: ret i32*
; CHECK: musttail call i8* @test_multiptrret_d(
; CHECK-NEXT: bitcast i8* {{.*}} to i32*
; CHECK-NEXT: ret i32*

declare i8* @test_multiptrret_c(i1 zeroext %b)
declare i8* @test_multiptrret_d(i1 zeroext %b)
define internal i16* @test_multiptrret_b(i1 zeroext %b) {
  br i1 %b, label %c, label %d
c:
  %c_rv = musttail call i8* @test_multiptrret_c(i1 zeroext %b)
  %c_v = bitcast i8* %c_rv to i16*
  ret i16* %c_v
d:
  %d_rv = musttail call i8* @test_multiptrret_d(i1 zeroext %b)
  %d_v = bitcast i8* %d_rv to i16*
  ret i16* %d_v
}
define i32* @test_multiptrret_a(i1 zeroext %b) {
  %rv = musttail call i16* @test_multiptrret_b(i1 zeroext %b)
  %v = bitcast i16* %rv to i32*
  ret i32* %v
}

; Inline a musttail call site which contains a normal return and a musttail call.
; CHECK: define i32 @test_mixedret_a(
; CHECK: br i1 %b
; CHECK: musttail call i32 @test_mixedret_c(
; CHECK-NEXT: ret i32
; CHECK: call i32 @test_mixedret_d(i1 zeroext %b)
; CHECK: add i32 1,
; CHECK-NOT: br
; CHECK: ret i32

declare i32 @test_mixedret_c(i1 zeroext %b)
declare i32 @test_mixedret_d(i1 zeroext %b)
define internal i32 @test_mixedret_b(i1 zeroext %b) {
  br i1 %b, label %c, label %d
c:
  %c_rv = musttail call i32 @test_mixedret_c(i1 zeroext %b)
  ret i32 %c_rv
d:
  %d_rv = call i32 @test_mixedret_d(i1 zeroext %b)
  %d_rv1 = add i32 1, %d_rv
  ret i32 %d_rv1
}
define i32 @test_mixedret_a(i1 zeroext %b) {
  %rv = musttail call i32 @test_mixedret_b(i1 zeroext %b)
  ret i32 %rv
}