1; REQUIRES: asserts
2; RUN: opt -loop-unswitch -enable-new-pm=0 -loop-unswitch-threshold 1000 -disable-output -stats -info-output-file - < %s | FileCheck --check-prefix=STATS %s
3; RUN: opt -S -loop-unswitch -enable-new-pm=0 -loop-unswitch-threshold 1000 -verify-loop-info -verify-dom-info < %s | FileCheck %s
4; RUN: opt -S -loop-unswitch -enable-new-pm=0 -loop-unswitch-threshold 1000 -verify-loop-info -verify-dom-info -enable-mssa-loop-dependency=true -verify-memoryssa < %s | FileCheck %s
5
6; STATS: 3 loop-unswitch - Number of switches unswitched
7
8; CHECK:        %1 = icmp eq i32 %c, 1
9; CHECK-NEXT:   br i1 %1, label %.split.us, label %..split_crit_edge
10
11; CHECK:      ..split_crit_edge:                                ; preds = %0
12; CHECK-NEXT:   br label %.split
13
14; CHECK:      .split.us:                                        ; preds = %0
15; CHECK-NEXT:   %2 = icmp eq i32 %d, 1
16; CHECK-NEXT:   br i1 %2, label %.split.us.split.us, label %.split.us..split.us.split_crit_edge
17
18; CHECK:      .split.us..split.us.split_crit_edge:              ; preds = %.split.us
19; CHECK-NEXT:   br label %.split.us.split
20
21; CHECK:      .split.us.split.us:                               ; preds = %.split.us
22; CHECK-NEXT:   br label %loop_begin.us.us
23
24; CHECK:      loop_begin.us.us:                                 ; preds = %loop_begin.backedge.us.us, %.split.us.split.us
25; CHECK-NEXT:   %var_val.us.us = load i32, i32* %var
26; CHECK-NEXT:   switch i32 1, label %second_switch.us.us [
27; CHECK-NEXT:     i32 1, label %inc.us.us
28
29; CHECK:      second_switch.us.us:                              ; preds = %loop_begin.us.us
30; CHECK-NEXT:   switch i32 1, label %default.us.us [
31; CHECK-NEXT:     i32 1, label %inc.us.us
32
33; CHECK:      inc.us.us:                                        ; preds = %second_switch.us.us, %loop_begin.us.us
34; CHECK-NEXT:   call void @incf() [[NOR_NUW:#[0-9]+]]
35; CHECK-NEXT:   br label %loop_begin.backedge.us.us
36
37; CHECK:      .split.us.split:                                  ; preds = %.split.us..split.us.split_crit_edge
38; CHECK-NEXT:   br label %loop_begin.us
39
40; CHECK:      loop_begin.us:                                    ; preds = %loop_begin.backedge.us, %.split.us.split
41; CHECK-NEXT:   %var_val.us = load i32, i32* %var
42; CHECK-NEXT:   switch i32 1, label %second_switch.us [
43; CHECK-NEXT:     i32 1, label %inc.us
44
45; CHECK:      second_switch.us:                                 ; preds = %loop_begin.us
46; CHECK-NEXT:   switch i32 %d, label %default.us [
47; CHECK-NEXT:     i32 1, label %second_switch.us.inc.us_crit_edge
48; CHECK-NEXT:   ]
49
50; CHECK:      second_switch.us.inc.us_crit_edge:                ; preds = %second_switch.us
51; CHECK-NEXT:   br i1 true, label %us-unreachable8, label %inc.us
52
53; CHECK:      inc.us:                                           ; preds = %second_switch.us.inc.us_crit_edge, %loop_begin.us
54; CHECK-NEXT:   call void @incf() [[NOR_NUW]]
55; CHECK-NEXT:   br label %loop_begin.backedge.us
56
57; CHECK:      .split:                                           ; preds = %..split_crit_edge
58; CHECK-NEXT:   %3 = icmp eq i32 %d, 1
59; CHECK-NEXT:   br i1 %3, label %.split.split.us, label %.split..split.split_crit_edge
60
61; CHECK:      .split..split.split_crit_edge:                    ; preds = %.split
62; CHECK-NEXT:   br label %.split.split
63
64; CHECK:      .split.split.us:                                  ; preds = %.split
65; CHECK-NEXT:   br label %loop_begin.us1
66
67; CHECK:      loop_begin.us1:                                   ; preds = %loop_begin.backedge.us6, %.split.split.us
68; CHECK-NEXT:   %var_val.us2 = load i32, i32* %var
69; CHECK-NEXT:   switch i32 %c, label %second_switch.us3 [
70; CHECK-NEXT:     i32 1, label %loop_begin.inc_crit_edge.us
71; CHECK-NEXT:   ]
72
73; CHECK:      second_switch.us3:                                ; preds = %loop_begin.us1
74; CHECK-NEXT:   switch i32 1, label %default.us5 [
75; CHECK-NEXT:     i32 1, label %inc.us4
76; CHECK-NEXT:   ]
77
78; CHECK:      inc.us4:                                          ; preds = %loop_begin.inc_crit_edge.us, %second_switch.us3
79; CHECK-NEXT:   call void @incf() [[NOR_NUW]]
80; CHECK-NEXT:   br label %loop_begin.backedge.us6
81
82; CHECK:      loop_begin.inc_crit_edge.us:                      ; preds = %loop_begin.us1
83; CHECK-NEXT:   br i1 true, label %us-unreachable.us-lcssa.us, label %inc.us4
84
85; CHECK:      .split.split:                                     ; preds = %.split..split.split_crit_edge
86; CHECK-NEXT:   br label %loop_begin
87
88; CHECK:      loop_begin:                                       ; preds = %loop_begin.backedge, %.split.split
89; CHECK-NEXT:   %var_val = load i32, i32* %var
90; CHECK-NEXT:   switch i32 %c, label %second_switch [
91; CHECK-NEXT:     i32 1, label %loop_begin.inc_crit_edge
92; CHECK-NEXT:   ]
93
94; CHECK:      loop_begin.inc_crit_edge:                         ; preds = %loop_begin
95; CHECK-NEXT:   br i1 true, label %us-unreachable.us-lcssa, label %inc
96
97; CHECK:      second_switch:                                    ; preds = %loop_begin
98; CHECK-NEXT:   switch i32 %d, label %default [
99; CHECK-NEXT:     i32 1, label %second_switch.inc_crit_edge
100; CHECK-NEXT:   ]
101
102; CHECK:      second_switch.inc_crit_edge:                      ; preds = %second_switch
103; CHECK-NEXT:   br i1 true, label %us-unreachable7, label %inc
104
105
106define i32 @test(i32* %var) {
107  %mem = alloca i32
108  store i32 2, i32* %mem
109  %c = load i32, i32* %mem
110  %d = load i32, i32* %mem
111
112  br label %loop_begin
113
114loop_begin:
115
116  %var_val = load i32, i32* %var
117
118  switch i32 %c, label %second_switch [
119      i32 1, label %inc
120  ]
121
122second_switch:
123  switch i32 %d, label %default [
124      i32 1, label %inc
125  ]
126
127inc:
128  call void @incf() noreturn nounwind
129  br label %loop_begin
130
131default:
132  br label %loop_begin
133
134loop_exit:
135  ret i32 0
136}
137
138declare void @incf() noreturn
139declare void @decf() noreturn
140
141; CHECK: attributes #0 = { noreturn }
142; CHECK: attributes [[NOR_NUW]] = { noreturn nounwind }
143