1; RUN: opt -S -jump-threading < %s | FileCheck %s
2
3declare void @foo()
4declare void @bar()
5declare void @baz()
6declare void @quux()
7
8
9; Jump threading of branch with select as condition.
10; Mostly theoretical since instruction combining simplifies all selects of
11; booleans where at least one operand is true/false/undef.
12
13; CHECK-LABEL: @test_br(
14; CHECK-NEXT: entry:
15; CHECK-NEXT: br i1 %cond, label %L1,
16define void @test_br(i1 %cond, i1 %value) nounwind {
17entry:
18  br i1 %cond, label %L0, label %L3
19L0:
20  %expr = select i1 %cond, i1 true, i1 %value
21  br i1 %expr, label %L1, label %L2
22
23L1:
24  call void @foo()
25  ret void
26L2:
27  call void @bar()
28  ret void
29L3:
30  call void @baz()
31  br label %L0
32}
33
34
35; Jump threading of switch with select as condition.
36
37; CHECK-LABEL: @test_switch(
38; CHECK-NEXT: entry:
39; CHECK-NEXT: br i1 %cond, label %L1,
40define void @test_switch(i1 %cond, i8 %value) nounwind {
41entry:
42  br i1 %cond, label %L0, label %L4
43L0:
44  %expr = select i1 %cond, i8 1, i8 %value
45  switch i8 %expr, label %L3 [i8 1, label %L1 i8 2, label %L2]
46
47L1:
48  call void @foo()
49  ret void
50L2:
51  call void @bar()
52  ret void
53L3:
54  call void @baz()
55  ret void
56L4:
57  call void @quux()
58  br label %L0
59}
60
61; Make sure the blocks in the indirectbr test aren't trivially removable as
62; successors by taking their addresses.
63@anchor = constant [3 x i8*] [
64  i8* blockaddress(@test_indirectbr, %L1),
65  i8* blockaddress(@test_indirectbr, %L2),
66  i8* blockaddress(@test_indirectbr, %L3)
67]
68
69
70; Jump threading of indirectbr with select as address.
71
72; CHECK-LABEL: @test_indirectbr(
73; CHECK-NEXT: entry:
74; CHECK-NEXT: br i1 %cond, label %L1, label %L3
75define void @test_indirectbr(i1 %cond, i8* %address) nounwind {
76entry:
77  br i1 %cond, label %L0, label %L3
78L0:
79  %indirect.goto.dest = select i1 %cond, i8* blockaddress(@test_indirectbr, %L1), i8* %address
80  indirectbr i8* %indirect.goto.dest, [label %L1, label %L2, label %L3]
81
82L1:
83  call void @foo()
84  ret void
85L2:
86  call void @bar()
87  ret void
88L3:
89  call void @baz()
90  ret void
91}
92
93
94; Jump threading of indirectbr with select as address.  Test increased
95; duplication threshold for cases where indirectbr is being threaded
96; through.
97
98; CHECK-LABEL: @test_indirectbr_thresh(
99; CHECK-NEXT: entry:
100; CHECK-NEXT: br i1 %cond, label %L1, label %L3
101; CHECK-NOT: indirectbr
102define void @test_indirectbr_thresh(i1 %cond, i8* %address) nounwind {
103entry:
104  br i1 %cond, label %L0, label %L3
105L0:
106  %indirect.goto.dest = select i1 %cond, i8* blockaddress(@test_indirectbr_thresh, %L1), i8* %address
107  call void @quux()
108  call void @quux()
109  call void @quux()
110  indirectbr i8* %indirect.goto.dest, [label %L1, label %L2, label %L3]
111
112L1:
113  call void @foo()
114  ret void
115L2:
116  call void @bar()
117  ret void
118L3:
119  call void @baz()
120  ret void
121}
122
123
124; A more complicated case: the condition is a select based on a comparison.
125
126; CHECK-LABEL: @test_switch_cmp(
127; CHECK-NEXT: entry:
128; CHECK-NEXT: br i1 %cond, label %L0, label %[[THREADED:[A-Za-z.0-9]+]]
129; CHECK: [[THREADED]]:
130; CHECK-NEXT: call void @quux
131; CHECK-NEXT: br label %L1
132define void @test_switch_cmp(i1 %cond, i32 %val, i8 %value) nounwind {
133entry:
134  br i1 %cond, label %L0, label %L4
135L0:
136  %val.phi = phi i32 [%val, %entry], [-1, %L4]
137  %cmp = icmp slt i32 %val.phi, 0
138  %expr = select i1 %cmp, i8 1, i8 %value
139  switch i8 %expr, label %L3 [i8 1, label %L1 i8 2, label %L2]
140
141L1:
142  call void @foo()
143  ret void
144L2:
145  call void @bar()
146  ret void
147L3:
148  call void @baz()
149  ret void
150L4:
151  call void @quux()
152  br label %L0
153}
154
155; Make sure the edge value of %0 from entry to L2 includes 0 and L3 is
156; reachable.
157; CHECK: test_switch_default
158; CHECK: entry:
159; CHECK: load
160; CHECK: icmp
161; CHECK: [[THREADED:[A-Za-z.0-9]+]]:
162; CHECK: store
163; CHECK: br
164; CHECK: L2:
165; CHECK: icmp
166define void @test_switch_default(i32* nocapture %status) nounwind {
167entry:
168  %0 = load i32, i32* %status, align 4
169  switch i32 %0, label %L2 [
170    i32 5061, label %L1
171    i32 0, label %L2
172  ]
173
174L1:
175  store i32 10025, i32* %status, align 4
176  br label %L2
177
178L2:
179  %1 = load i32, i32* %status, align 4
180  %cmp57.i = icmp eq i32 %1, 0
181  br i1 %cmp57.i, label %L3, label %L4
182
183L3:
184  store i32 10000, i32* %status, align 4
185  br label %L4
186
187L4:
188  ret void
189}
190
191define void @unfold1(double %x, double %y) nounwind {
192entry:
193  %sub = fsub double %x, %y
194  %cmp = fcmp ogt double %sub, 1.000000e+01
195  br i1 %cmp, label %cond.end4, label %cond.false
196
197cond.false:                                       ; preds = %entry
198  %add = fadd double %x, %y
199  %cmp1 = fcmp ogt double %add, 1.000000e+01
200  %add. = select i1 %cmp1, double %add, double 0.000000e+00
201  br label %cond.end4
202
203cond.end4:                                        ; preds = %entry, %cond.false
204  %cond5 = phi double [ %add., %cond.false ], [ %sub, %entry ]
205  %cmp6 = fcmp oeq double %cond5, 0.000000e+00
206  br i1 %cmp6, label %if.then, label %if.end
207
208if.then:                                          ; preds = %cond.end4
209  call void @foo()
210  br label %if.end
211
212if.end:                                           ; preds = %if.then, %cond.end4
213  ret void
214
215; CHECK-LABEL: @unfold1
216; CHECK: br i1 %cmp, label %cond.end4, label %cond.false
217; CHECK: br i1 %cmp1, label %cond.end4, label %if.then
218; CHECK: br i1 %cmp6, label %if.then, label %if.end
219; CHECK: br label %if.end
220}
221
222
223define void @unfold2(i32 %x, i32 %y) nounwind {
224entry:
225  %sub = sub nsw i32 %x, %y
226  %cmp = icmp sgt i32 %sub, 10
227  br i1 %cmp, label %cond.end4, label %cond.false
228
229cond.false:                                       ; preds = %entry
230  %add = add nsw i32 %x, %y
231  %cmp1 = icmp sgt i32 %add, 10
232  %add. = select i1 %cmp1, i32 0, i32 %add
233  br label %cond.end4
234
235cond.end4:                                        ; preds = %entry, %cond.false
236  %cond5 = phi i32 [ %add., %cond.false ], [ %sub, %entry ]
237  %cmp6 = icmp eq i32 %cond5, 0
238  br i1 %cmp6, label %if.then, label %if.end
239
240if.then:                                          ; preds = %cond.end4
241  call void @foo()
242  br label %if.end
243
244if.end:                                           ; preds = %if.then, %cond.end4
245  ret void
246
247; CHECK-LABEL: @unfold2
248; CHECK: br i1 %cmp, label %if.end, label %cond.false
249; CHECK: br i1 %cmp1, label %if.then, label %cond.end4
250; CHECK: br i1 %cmp6, label %if.then, label %if.end
251; CHECK: br label %if.end
252}
253
254
255define i32 @unfold3(i32 %u, i32 %v, i32 %w, i32 %x, i32 %y, i32 %z, i32 %j) nounwind {
256entry:
257  %add3 = add nsw i32 %j, 2
258  %cmp.i = icmp slt i32 %u, %v
259  br i1 %cmp.i, label %.exit, label %cond.false.i
260
261cond.false.i:                                     ; preds = %entry
262  %cmp4.i = icmp sgt i32 %u, %v
263  br i1 %cmp4.i, label %.exit, label %cond.false.6.i
264
265cond.false.6.i:                                   ; preds = %cond.false.i
266  %cmp8.i = icmp slt i32 %w, %x
267  br i1 %cmp8.i, label %.exit, label %cond.false.10.i
268
269cond.false.10.i:                                  ; preds = %cond.false.6.i
270  %cmp13.i = icmp sgt i32 %w, %x
271  br i1 %cmp13.i, label %.exit, label %cond.false.15.i
272
273cond.false.15.i:                                  ; preds = %cond.false.10.i
274  %phitmp = icmp sge i32 %y, %z
275  br label %.exit
276
277.exit:                                  ; preds = %entry, %cond.false.i, %cond.false.6.i, %cond.false.10.i, %cond.false.15.i
278  %cond23.i = phi i1 [ false, %entry ], [ true, %cond.false.i ], [ false, %cond.false.6.i ], [ %phitmp, %cond.false.15.i ], [ true, %cond.false.10.i ]
279  %j.add3 = select i1 %cond23.i, i32 %j, i32 %add3
280  ret i32 %j.add3
281
282; CHECK-LABEL: @unfold3
283; CHECK: br i1 %cmp.i, label %.exit.thread2, label %cond.false.i
284; CHECK: br i1 %cmp4.i, label %.exit.thread, label %cond.false.6.i
285; CHECK: br i1 %cmp8.i, label %.exit.thread2, label %cond.false.10.i
286; CHECK: br i1 %cmp13.i, label %.exit.thread, label %.exit
287; CHECK: br i1 %phitmp, label %.exit.thread, label %.exit.thread2
288; CHECK: br label %.exit.thread2
289}
290