1; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
2; RUN: llc < %s -mtriple=i686-- -O3 -verify-machineinstrs | FileCheck %s
3
4; Tests for using callbr as an asm-goto wrapper
5
6; Test 1 - fallthrough label gets removed, but the fallthrough code that is
7; unreachable due to asm ending on a jmp is still left in.
8define i32 @test1(i32 %a) {
9; CHECK-LABEL: test1:
10; CHECK:       # %bb.0: # %entry
11; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %eax
12; CHECK-NEXT:    addl $4, %eax
13; CHECK-NEXT:    #APP
14; CHECK-NEXT:    xorl %eax, %eax
15; CHECK-NEXT:    jmp .Ltmp0
16; CHECK-NEXT:    #NO_APP
17; CHECK-NEXT:  # %bb.1: # %normal
18; CHECK-NEXT:    xorl %eax, %eax
19; CHECK-NEXT:    retl
20; CHECK-NEXT:  .Ltmp0: # Block address taken
21; CHECK-NEXT:  .LBB0_2: # %fail
22; CHECK-NEXT:    movl $1, %eax
23; CHECK-NEXT:    retl
24entry:
25  %0 = add i32 %a, 4
26  callbr void asm "xorl $0, $0; jmp ${1:l}", "r,i,~{dirflag},~{fpsr},~{flags}"(i32 %0, ptr blockaddress(@test1, %fail)) to label %normal [label %fail]
27
28normal:
29  ret i32 0
30
31fail:
32  ret i32 1
33}
34
35; Test 1b - Like test 1 but using `asm inteldialect`.
36define i32 @test1b(i32 %a) {
37; CHECK-LABEL: test1b:
38; CHECK:       # %bb.0: # %entry
39; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %eax
40; CHECK-NEXT:    addl $4, %eax
41; CHECK-NEXT:    #APP
42; CHECK-EMPTY:
43; CHECK-NEXT:    xorl %eax, %eax
44; CHECK-NEXT:    jmp .Ltmp1
45; CHECK-EMPTY:
46; CHECK-NEXT:    #NO_APP
47; CHECK-NEXT:  # %bb.1: # %normal
48; CHECK-NEXT:    xorl %eax, %eax
49; CHECK-NEXT:    retl
50; CHECK-NEXT:  .Ltmp1: # Block address taken
51; CHECK-NEXT:  .LBB1_2: # %fail
52; CHECK-NEXT:    movl $1, %eax
53; CHECK-NEXT:    retl
54entry:
55  %0 = add i32 %a, 4
56  callbr void asm inteldialect "xor $0, $0; jmp ${1:l}", "r,i,~{dirflag},~{fpsr},~{flags}"(i32 %0, ptr blockaddress(@test1b, %fail)) to label %normal [label %fail]
57
58normal:
59  ret i32 0
60
61fail:
62  ret i32 1
63}
64
65; Test 2 - callbr terminates an unreachable block, function gets simplified
66; to a trivial zero return.
67define i32 @test2(i32 %a) {
68; CHECK-LABEL: test2:
69; CHECK:       # %bb.0: # %entry
70; CHECK-NEXT:    xorl %eax, %eax
71; CHECK-NEXT:    retl
72entry:
73  br label %normal
74
75unreachableasm:
76  %0 = add i32 %a, 4
77  callbr void asm sideeffect "xorl $0, $0; jmp ${1:l}", "r,i,~{dirflag},~{fpsr},~{flags}"(i32 %0, ptr blockaddress(@test2, %fail)) to label %normal [label %fail]
78
79normal:
80  ret i32 0
81
82fail:
83  ret i32 1
84}
85
86; Test 3 - asm-goto implements a loop. The loop gets recognized, but many loop
87; transforms fail due to canonicalization having callbr exceptions. Trivial
88; blocks at labels 1 and 3 also don't get simplified due to callbr.
89define i32 @test3(i32 %a) {
90; CHECK-LABEL: test3:
91; CHECK:       # %bb.0: # %entry
92; CHECK-NEXT:  .Ltmp2: # Block address taken
93; CHECK-NEXT:  .LBB3_1: # %label01
94; CHECK-NEXT:    # =>This Loop Header: Depth=1
95; CHECK-NEXT:    # Child Loop BB3_2 Depth 2
96; CHECK-NEXT:    # Child Loop BB3_3 Depth 3
97; CHECK-NEXT:    # Child Loop BB3_4 Depth 4
98; CHECK-NEXT:  .Ltmp3: # Block address taken
99; CHECK-NEXT:  .LBB3_2: # %label02
100; CHECK-NEXT:    # Parent Loop BB3_1 Depth=1
101; CHECK-NEXT:    # => This Loop Header: Depth=2
102; CHECK-NEXT:    # Child Loop BB3_3 Depth 3
103; CHECK-NEXT:    # Child Loop BB3_4 Depth 4
104; CHECK-NEXT:    addl $4, {{[0-9]+}}(%esp)
105; CHECK-NEXT:  .Ltmp4: # Block address taken
106; CHECK-NEXT:  .LBB3_3: # %label03
107; CHECK-NEXT:    # Parent Loop BB3_1 Depth=1
108; CHECK-NEXT:    # Parent Loop BB3_2 Depth=2
109; CHECK-NEXT:    # => This Loop Header: Depth=3
110; CHECK-NEXT:    # Child Loop BB3_4 Depth 4
111; CHECK-NEXT:  .Ltmp5: # Block address taken
112; CHECK-NEXT:  .LBB3_4: # %label04
113; CHECK-NEXT:    # Parent Loop BB3_1 Depth=1
114; CHECK-NEXT:    # Parent Loop BB3_2 Depth=2
115; CHECK-NEXT:    # Parent Loop BB3_3 Depth=3
116; CHECK-NEXT:    # => This Inner Loop Header: Depth=4
117; CHECK-NEXT:    #APP
118; CHECK-NEXT:    jmp .Ltmp2
119; CHECK-NEXT:    jmp .Ltmp3
120; CHECK-NEXT:    jmp .Ltmp4
121; CHECK-NEXT:    #NO_APP
122; CHECK-NEXT:  # %bb.5: # %normal0
123; CHECK-NEXT:    # in Loop: Header=BB3_4 Depth=4
124; CHECK-NEXT:    #APP
125; CHECK-NEXT:    jmp .Ltmp2
126; CHECK-NEXT:    jmp .Ltmp3
127; CHECK-NEXT:    jmp .Ltmp4
128; CHECK-NEXT:    jmp .Ltmp5
129; CHECK-NEXT:    #NO_APP
130; CHECK-NEXT:  # %bb.6: # %normal1
131; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %eax
132; CHECK-NEXT:    retl
133entry:
134  %a.addr = alloca i32, align 4
135  store i32 %a, ptr %a.addr, align 4
136  br label %label01
137
138label01:                                          ; preds = %normal0, %label04, %entry
139  br label %label02
140
141label02:                                          ; preds = %normal0, %label04, %label01
142  %0 = load i32, ptr %a.addr, align 4
143  %add = add nsw i32 %0, 4
144  store i32 %add, ptr %a.addr, align 4
145  br label %label03
146
147label03:                                          ; preds = %normal0, %label04, %label02
148  br label %label04
149
150label04:                                          ; preds = %normal0, %label03
151  callbr void asm sideeffect "jmp ${0:l}; jmp ${1:l}; jmp ${2:l}", "i,i,i,~{dirflag},~{fpsr},~{flags}"(ptr blockaddress(@test3, %label01), ptr blockaddress(@test3, %label02), ptr blockaddress(@test3, %label03))
152          to label %normal0 [label %label01, label %label02, label %label03]
153
154normal0:                                          ; preds = %label04
155  callbr void asm sideeffect "jmp ${0:l}; jmp ${1:l}; jmp ${2:l}; jmp ${3:l}", "i,i,i,i,~{dirflag},~{fpsr},~{flags}"(ptr blockaddress(@test3, %label01), ptr blockaddress(@test3, %label02), ptr blockaddress(@test3, %label03), ptr blockaddress(@test3, %label04))
156          to label %normal1 [label %label01, label %label02, label %label03, label %label04]
157
158normal1:                                          ; preds = %normal0
159  %1 = load i32, ptr %a.addr, align 4
160  ret i32 %1
161}
162
163; Test 4 - asm-goto referenced with the 'l' (ell) modifier and not.
164define void @test4() {
165; CHECK-LABEL: test4:
166; CHECK:       # %bb.0: # %entry
167; CHECK-NEXT:    #APP
168; CHECK-NEXT:    ja .Ltmp6
169; CHECK-NEXT:    #NO_APP
170; CHECK-NEXT:  # %bb.1: # %asm.fallthrough
171; CHECK-NEXT:    #APP
172; CHECK-NEXT:    ja .Ltmp6
173; CHECK-NEXT:    #NO_APP
174; CHECK-NEXT:  .Ltmp6: # Block address taken
175; CHECK-NEXT:  .LBB4_3: # %quux
176; CHECK-NEXT:    retl
177entry:
178  callbr void asm sideeffect "ja $0", "i,~{dirflag},~{fpsr},~{flags}"(ptr blockaddress(@test4, %quux))
179          to label %asm.fallthrough [label %quux]
180
181asm.fallthrough:                                  ; preds = %entry
182  callbr void asm sideeffect "ja ${0:l}", "i,~{dirflag},~{fpsr},~{flags}"(ptr blockaddress(@test4, %quux))
183          to label %cleanup [label %quux]
184
185quux:                                             ; preds = %asm.fallthrough, %entry
186  br label %cleanup
187
188cleanup:                                          ; preds = %asm.fallthrough, %quux
189  ret void
190}
191