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
|
; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=i686-- -O3 | FileCheck %s
; Tests for using callbr as an asm-goto wrapper
; Test 1 - fallthrough label gets removed, but the fallthrough code that is
; unreachable due to asm ending on a jmp is still left in.
define i32 @test1(i32 %a) {
; CHECK-LABEL: test1:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: movl {{[0-9]+}}(%esp), %eax
; CHECK-NEXT: addl $4, %eax
; CHECK-NEXT: #APP
; CHECK-NEXT: xorl %eax, %eax
; CHECK-NEXT: jmp .Ltmp0
; CHECK-NEXT: #NO_APP
; CHECK-NEXT: .LBB0_1: # %normal
; CHECK-NEXT: xorl %eax, %eax
; CHECK-NEXT: retl
; CHECK-NEXT: .Ltmp0: # Block address taken
; CHECK-NEXT: .LBB0_2: # %fail
; CHECK-NEXT: movl $1, %eax
; CHECK-NEXT: retl
entry:
%0 = add i32 %a, 4
callbr void asm "xorl $0, $0; jmp ${1:l}", "r,X,~{dirflag},~{fpsr},~{flags}"(i32 %0, i8* blockaddress(@test1, %fail)) to label %normal [label %fail]
normal:
ret i32 0
fail:
ret i32 1
}
; Test 2 - callbr terminates an unreachable block, function gets simplified
; to a trivial zero return.
define i32 @test2(i32 %a) {
; CHECK-LABEL: test2:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: xorl %eax, %eax
; CHECK-NEXT: retl
entry:
br label %normal
unreachableasm:
%0 = add i32 %a, 4
callbr void asm sideeffect "xorl $0, $0; jmp ${1:l}", "r,X,~{dirflag},~{fpsr},~{flags}"(i32 %0, i8* blockaddress(@test2, %fail)) to label %normal [label %fail]
normal:
ret i32 0
fail:
ret i32 1
}
; Test 3 - asm-goto implements a loop. The loop gets recognized, but many loop
; transforms fail due to canonicalization having callbr exceptions. Trivial
; blocks at labels 1 and 3 also don't get simplified due to callbr.
define dso_local i32 @test3(i32 %a) {
; CHECK-LABEL: test3:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: .Ltmp1: # Block address taken
; CHECK-NEXT: .LBB2_1: # %label01
; CHECK-NEXT: # =>This Loop Header: Depth=1
; CHECK-NEXT: # Child Loop BB2_2 Depth 2
; CHECK-NEXT: # Child Loop BB2_3 Depth 3
; CHECK-NEXT: # Child Loop BB2_4 Depth 4
; CHECK-NEXT: .Ltmp2: # Block address taken
; CHECK-NEXT: .LBB2_2: # %label02
; CHECK-NEXT: # Parent Loop BB2_1 Depth=1
; CHECK-NEXT: # => This Loop Header: Depth=2
; CHECK-NEXT: # Child Loop BB2_3 Depth 3
; CHECK-NEXT: # Child Loop BB2_4 Depth 4
; CHECK-NEXT: addl $4, {{[0-9]+}}(%esp)
; CHECK-NEXT: .Ltmp3: # Block address taken
; CHECK-NEXT: .LBB2_3: # %label03
; CHECK-NEXT: # Parent Loop BB2_1 Depth=1
; CHECK-NEXT: # Parent Loop BB2_2 Depth=2
; CHECK-NEXT: # => This Loop Header: Depth=3
; CHECK-NEXT: # Child Loop BB2_4 Depth 4
; CHECK-NEXT: .p2align 4, 0x90
; CHECK-NEXT: .Ltmp4: # Block address taken
; CHECK-NEXT: .LBB2_4: # %label04
; CHECK-NEXT: # Parent Loop BB2_1 Depth=1
; CHECK-NEXT: # Parent Loop BB2_2 Depth=2
; CHECK-NEXT: # Parent Loop BB2_3 Depth=3
; CHECK-NEXT: # => This Inner Loop Header: Depth=4
; CHECK-NEXT: #APP
; CHECK-NEXT: jmp .Ltmp1
; CHECK-NEXT: jmp .Ltmp2
; CHECK-NEXT: jmp .Ltmp3
; CHECK-NEXT: #NO_APP
; CHECK-NEXT: .LBB2_5: # %normal0
; CHECK-NEXT: # in Loop: Header=BB2_4 Depth=4
; CHECK-NEXT: #APP
; CHECK-NEXT: jmp .Ltmp1
; CHECK-NEXT: jmp .Ltmp2
; CHECK-NEXT: jmp .Ltmp3
; CHECK-NEXT: jmp .Ltmp4
; CHECK-NEXT: #NO_APP
; CHECK-NEXT: .LBB2_6: # %normal1
; CHECK-NEXT: movl {{[0-9]+}}(%esp), %eax
; CHECK-NEXT: retl
entry:
%a.addr = alloca i32, align 4
store i32 %a, i32* %a.addr, align 4
br label %label01
label01: ; preds = %normal0, %label04, %entry
br label %label02
label02: ; preds = %normal0, %label04, %label01
%0 = load i32, i32* %a.addr, align 4
%add = add nsw i32 %0, 4
store i32 %add, i32* %a.addr, align 4
br label %label03
label03: ; preds = %normal0, %label04, %label02
br label %label04
label04: ; preds = %normal0, %label03
callbr void asm sideeffect "jmp ${0:l}; jmp ${1:l}; jmp ${2:l}", "X,X,X,~{dirflag},~{fpsr},~{flags}"(i8* blockaddress(@test3, %label01), i8* blockaddress(@test3, %label02), i8* blockaddress(@test3, %label03))
to label %normal0 [label %label01, label %label02, label %label03]
normal0: ; preds = %label04
callbr void asm sideeffect "jmp ${0:l}; jmp ${1:l}; jmp ${2:l}; jmp ${3:l}", "X,X,X,X,~{dirflag},~{fpsr},~{flags}"(i8* blockaddress(@test3, %label01), i8* blockaddress(@test3, %label02), i8* blockaddress(@test3, %label03), i8* blockaddress(@test3, %label04))
to label %normal1 [label %label01, label %label02, label %label03, label %label04]
normal1: ; preds = %normal0
%1 = load i32, i32* %a.addr, align 4
ret i32 %1
}
; Test 4 - asm-goto referenced with the 'l' (ell) modifier and not.
define void @test4() {
; CHECK-LABEL: test4:
; CHECK: # %bb.0:
; CHECK-NEXT: #APP
; CHECK-NOT: ja .Ltmp50
; CHECK-NEXT: ja .Ltmp5
; CHECK-NEXT: #NO_APP
; CHECK-NEXT: .LBB3_1:
; CHECK-NEXT: #APP
; CHECK-NOT: ja .Ltmp50
; CHECK-NEXT: ja .Ltmp5
; CHECK-NEXT: #NO_APP
; CHECK-NEXT: jmp .LBB3_3
entry:
callbr void asm sideeffect "ja $0", "X,~{dirflag},~{fpsr},~{flags}"(i8* blockaddress(@test4, %quux))
to label %asm.fallthrough [label %quux]
asm.fallthrough: ; preds = %entry
callbr void asm sideeffect "ja ${0:l}", "X,~{dirflag},~{fpsr},~{flags}"(i8* blockaddress(@test4, %quux))
to label %cleanup [label %quux]
quux: ; preds = %asm.fallthrough, %entry
br label %cleanup
cleanup: ; preds = %asm.fallthrough, %quux
ret void
}
|
