1; RUN: llc < %s -asm-verbose=false | FileCheck %s
2
3; Test the CFG stackifier pass.
4
5target datalayout = "e-p:32:32-i64:64-n32:64-S128"
6target triple = "wasm32-unknown-unknown"
7
8declare void @something()
9
10; Test that loops are made contiguous, even in the presence of split backedges.
11
12; CHECK-LABEL: test0:
13; CHECK: loop
14; CHECK: add
15; CHECK: br_if
16; CHECK: call
17; CHECK: br $BB0_1{{$}}
18; CHECK: return{{$}}
19define void @test0(i32 %n) {
20entry:
21  br label %header
22
23header:
24  %i = phi i32 [ 0, %entry ], [ %i.next, %back ]
25  %i.next = add i32 %i, 1
26
27  %c = icmp slt i32 %i.next, %n
28  br i1 %c, label %back, label %exit
29
30exit:
31  ret void
32
33back:
34  call void @something()
35  br label %header
36}
37
38; Same as test0, but the branch condition is reversed.
39
40; CHECK-LABEL: test1:
41; CHECK: loop
42; CHECK: add
43; CHECK: br_if
44; CHECK: call
45; CHECK: br $BB1_1{{$}}
46; CHECK: return{{$}}
47define void @test1(i32 %n) {
48entry:
49  br label %header
50
51header:
52  %i = phi i32 [ 0, %entry ], [ %i.next, %back ]
53  %i.next = add i32 %i, 1
54
55  %c = icmp sge i32 %i.next, %n
56  br i1 %c, label %exit, label %back
57
58exit:
59  ret void
60
61back:
62  call void @something()
63  br label %header
64}
65
66; Test that a simple loop is handled as expected.
67
68; CHECK-LABEL: test2:
69; CHECK: block $BB2_2{{$}}
70; CHECK: br_if $BB2_2, {{.*}}
71; CHECK: BB2_1:
72; CHECK: br_if $BB2_1, (get_local 16){{$}}
73; CHECK: BB2_2:
74; CHECK: return{{$}}
75define void @test2(double* nocapture %p, i32 %n) {
76entry:
77  %cmp.4 = icmp sgt i32 %n, 0
78  br i1 %cmp.4, label %for.body.preheader, label %for.end
79
80for.body.preheader:
81  br label %for.body
82
83for.body:
84  %i.05 = phi i32 [ %inc, %for.body ], [ 0, %for.body.preheader ]
85  %arrayidx = getelementptr inbounds double, double* %p, i32 %i.05
86  %0 = load double, double* %arrayidx, align 8
87  %mul = fmul double %0, 3.200000e+00
88  store double %mul, double* %arrayidx, align 8
89  %inc = add nuw nsw i32 %i.05, 1
90  %exitcond = icmp eq i32 %inc, %n
91  br i1 %exitcond, label %for.end.loopexit, label %for.body
92
93for.end.loopexit:
94  br label %for.end
95
96for.end:
97  ret void
98}
99
100; CHECK-LABEL: doublediamond:
101; CHECK: block $BB3_5{{$}}
102; CHECK: block $BB3_4{{$}}
103; CHECK: block $BB3_2{{$}}
104; CHECK: br_if $BB3_2, (get_local 7){{$}}
105; CHECK: br $BB3_5{{$}}
106; CHECK: BB3_2:
107; CHECK: br_if $BB3_4, (get_local 10){{$}}
108; CHECK: br $BB3_5{{$}}
109; CHECK: BB3_4:
110; CHECK: BB3_5:
111; CHECK: return (get_local 6){{$}}
112define i32 @doublediamond(i32 %a, i32 %b, i32* %p) {
113entry:
114  %c = icmp eq i32 %a, 0
115  %d = icmp eq i32 %b, 0
116  store volatile i32 0, i32* %p
117  br i1 %c, label %true, label %false
118true:
119  store volatile i32 1, i32* %p
120  br label %exit
121false:
122  store volatile i32 2, i32* %p
123  br i1 %d, label %ft, label %ff
124ft:
125  store volatile i32 3, i32* %p
126  br label %exit
127ff:
128  store volatile i32 4, i32* %p
129  br label %exit
130exit:
131  store volatile i32 5, i32* %p
132  ret i32 0
133}
134
135; CHECK-LABEL: triangle:
136; CHECK: block $BB4_2{{$}}
137; CHECK: br_if $BB4_2, (get_local 5){{$}}
138; CHECK: BB4_2:
139; CHECK: return (get_local 4){{$}}
140define i32 @triangle(i32* %p, i32 %a) {
141entry:
142  %c = icmp eq i32 %a, 0
143  store volatile i32 0, i32* %p
144  br i1 %c, label %true, label %exit
145true:
146  store volatile i32 1, i32* %p
147  br label %exit
148exit:
149  store volatile i32 2, i32* %p
150  ret i32 0
151}
152
153; CHECK-LABEL: diamond:
154; CHECK: block $BB5_3{{$}}
155; CHECK: block $BB5_2{{$}}
156; CHECK: br_if $BB5_2, (get_local 5){{$}}
157; CHECK: br $BB5_3{{$}}
158; CHECK: BB5_2:
159; CHECK: BB5_3:
160; CHECK: return (get_local 4){{$}}
161define i32 @diamond(i32* %p, i32 %a) {
162entry:
163  %c = icmp eq i32 %a, 0
164  store volatile i32 0, i32* %p
165  br i1 %c, label %true, label %false
166true:
167  store volatile i32 1, i32* %p
168  br label %exit
169false:
170  store volatile i32 2, i32* %p
171  br label %exit
172exit:
173  store volatile i32 3, i32* %p
174  ret i32 0
175}
176
177; CHECK-LABEL: single_block:
178; CHECK-NOT: br
179; CHECK: return (get_local 2){{$}}
180define i32 @single_block(i32* %p) {
181entry:
182  store volatile i32 0, i32* %p
183  ret i32 0
184}
185
186; CHECK-LABEL: minimal_loop:
187; CHECK-NOT: br
188; CHECK: BB7_1:
189; CHECK: i32.store (get_local 1), (get_local 3){{$}}
190; CHECK: br $BB7_1{{$}}
191define i32 @minimal_loop(i32* %p) {
192entry:
193  store volatile i32 0, i32* %p
194  br label %loop
195loop:
196  store volatile i32 1, i32* %p
197  br label %loop
198}
199
200; CHECK-LABEL: simple_loop:
201; CHECK-NOT: br
202; CHECK: BB8_1:
203; CHECK: loop $BB8_2{{$}}
204; CHECK: br_if $BB8_1, (get_local 6){{$}}
205; CHECK: return (get_local 4){{$}}
206define i32 @simple_loop(i32* %p, i32 %a) {
207entry:
208  %c = icmp eq i32 %a, 0
209  store volatile i32 0, i32* %p
210  br label %loop
211loop:
212  store volatile i32 1, i32* %p
213  br i1 %c, label %loop, label %exit
214exit:
215  store volatile i32 2, i32* %p
216  ret i32 0
217}
218
219; CHECK-LABEL: doubletriangle:
220; CHECK: block $BB9_4{{$}}
221; CHECK: block $BB9_3{{$}}
222; CHECK: br_if $BB9_4, (get_local 7){{$}}
223; CHECK: br_if $BB9_3, (get_local 10){{$}}
224; CHECK: BB9_3:
225; CHECK: BB9_4:
226; CHECK: return (get_local 6){{$}}
227define i32 @doubletriangle(i32 %a, i32 %b, i32* %p) {
228entry:
229  %c = icmp eq i32 %a, 0
230  %d = icmp eq i32 %b, 0
231  store volatile i32 0, i32* %p
232  br i1 %c, label %true, label %exit
233true:
234  store volatile i32 2, i32* %p
235  br i1 %d, label %tt, label %tf
236tt:
237  store volatile i32 3, i32* %p
238  br label %tf
239tf:
240  store volatile i32 4, i32* %p
241  br label %exit
242exit:
243  store volatile i32 5, i32* %p
244  ret i32 0
245}
246
247; CHECK-LABEL: ifelse_earlyexits:
248; CHECK: block $BB10_4{{$}}
249; CHECK: block $BB10_2{{$}}
250; CHECK: br_if $BB10_2, (get_local 7){{$}}
251; CHECK: br $BB10_4{{$}}
252; CHECK: BB10_2:
253; CHECK: br_if $BB10_4, (get_local 10){{$}}
254; CHECK: BB10_4:
255; CHECK: return (get_local 6){{$}}
256define i32 @ifelse_earlyexits(i32 %a, i32 %b, i32* %p) {
257entry:
258  %c = icmp eq i32 %a, 0
259  %d = icmp eq i32 %b, 0
260  store volatile i32 0, i32* %p
261  br i1 %c, label %true, label %false
262true:
263  store volatile i32 1, i32* %p
264  br label %exit
265false:
266  store volatile i32 2, i32* %p
267  br i1 %d, label %ft, label %exit
268ft:
269  store volatile i32 3, i32* %p
270  br label %exit
271exit:
272  store volatile i32 4, i32* %p
273  ret i32 0
274}
275
276; Test that nested loops are handled.
277
278declare void @bar()
279
280define void @test3(i32 %w)  {
281entry:
282  br i1 undef, label %outer.ph, label %exit
283
284outer.ph:
285  br label %outer
286
287outer:
288  %tobool = icmp eq i32 undef, 0
289  br i1 %tobool, label %inner, label %unreachable
290
291unreachable:
292  unreachable
293
294inner:
295  %c = icmp eq i32 undef, %w
296  br i1 %c, label %if.end, label %inner
297
298exit:
299  ret void
300
301if.end:
302  call void @bar()
303  br label %outer
304}
305