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1; RUN: opt < %s -gvn -S | FileCheck %s
2
3%struct.A = type { i32 (...)** }
4@_ZTV1A = available_externally unnamed_addr constant [4 x i8*] [i8* null, i8* bitcast (i8** @_ZTI1A to i8*), i8* bitcast (i32 (%struct.A*)* @_ZN1A3fooEv to i8*), i8* bitcast (i32 (%struct.A*)* @_ZN1A3barEv to i8*)], align 8
5@_ZTI1A = external constant i8*
6
7; Checks if indirect calls can be replaced with direct
8; assuming that %vtable == @_ZTV1A (with alignment).
9; Checking const propagation across other BBs
10; CHECK-LABEL: define void @_Z1gb(
11
12define void @_Z1gb(i1 zeroext %p) {
13entry:
14  %call = tail call noalias i8* @_Znwm(i64 8) #4
15  %0 = bitcast i8* %call to %struct.A*
16  tail call void @_ZN1AC1Ev(%struct.A* %0) #1
17  %1 = bitcast i8* %call to i8***
18  %vtable = load i8**, i8*** %1, align 8
19  %cmp.vtables = icmp eq i8** %vtable, getelementptr inbounds ([4 x i8*], [4 x i8*]* @_ZTV1A, i64 0, i64 2)
20  tail call void @llvm.assume(i1 %cmp.vtables)
21  br i1 %p, label %if.then, label %if.else
22
23if.then:                                          ; preds = %entry
24  %vtable1.cast = bitcast i8** %vtable to i32 (%struct.A*)**
25  %2 = load i32 (%struct.A*)*, i32 (%struct.A*)** %vtable1.cast, align 8
26
27  ; CHECK: call i32 @_ZN1A3fooEv(
28  %call2 = tail call i32 %2(%struct.A* %0) #1
29
30  br label %if.end
31
32if.else:                                          ; preds = %entry
33  %vfn47 = getelementptr inbounds i8*, i8** %vtable, i64 1
34  %vfn4 = bitcast i8** %vfn47 to i32 (%struct.A*)**
35
36  ; CHECK: call i32 @_ZN1A3barEv(
37  %3 = load i32 (%struct.A*)*, i32 (%struct.A*)** %vfn4, align 8
38
39  %call5 = tail call i32 %3(%struct.A* %0) #1
40  br label %if.end
41
42if.end:                                           ; preds = %if.else, %if.then
43  ret void
44}
45
46; Check integration with invariant.group handling
47; CHECK-LABEL: define void @invariantGroupHandling(i1 zeroext %p) {
48define void @invariantGroupHandling(i1 zeroext %p) {
49entry:
50  %call = tail call noalias i8* @_Znwm(i64 8) #4
51  %0 = bitcast i8* %call to %struct.A*
52  tail call void @_ZN1AC1Ev(%struct.A* %0) #1
53  %1 = bitcast i8* %call to i8***
54  %vtable = load i8**, i8*** %1, align 8, !invariant.group !0
55  %cmp.vtables = icmp eq i8** %vtable, getelementptr inbounds ([4 x i8*], [4 x i8*]* @_ZTV1A, i64 0, i64 2)
56  tail call void @llvm.assume(i1 %cmp.vtables)
57  br i1 %p, label %if.then, label %if.else
58
59if.then:                                          ; preds = %entry
60  %vtable1.cast = bitcast i8** %vtable to i32 (%struct.A*)**
61  %2 = load i32 (%struct.A*)*, i32 (%struct.A*)** %vtable1.cast, align 8
62
63; CHECK: call i32 @_ZN1A3fooEv(
64  %call2 = tail call i32 %2(%struct.A* %0) #1
65  %vtable1 = load i8**, i8*** %1, align 8, !invariant.group !0
66  %vtable2.cast = bitcast i8** %vtable1 to i32 (%struct.A*)**
67  %call1 = load i32 (%struct.A*)*, i32 (%struct.A*)** %vtable2.cast, align 8
68; CHECK: call i32 @_ZN1A3fooEv(
69  %callx = tail call i32 %call1(%struct.A* %0) #1
70
71  %vtable2 = load i8**, i8*** %1, align 8, !invariant.group !0
72  %vtable3.cast = bitcast i8** %vtable2 to i32 (%struct.A*)**
73  %call4 = load i32 (%struct.A*)*, i32 (%struct.A*)** %vtable3.cast, align 8
74; CHECK: call i32 @_ZN1A3fooEv(
75  %cally = tail call i32 %call4(%struct.A* %0) #1
76
77  %b = bitcast i8* %call to %struct.A**
78  %vtable3 = load %struct.A*, %struct.A** %b, align 8, !invariant.group !0
79  %vtable4.cast = bitcast %struct.A* %vtable3 to i32 (%struct.A*)**
80  %vfun = load i32 (%struct.A*)*, i32 (%struct.A*)** %vtable4.cast, align 8
81; CHECK: call i32 @_ZN1A3fooEv(
82  %unknown = tail call i32 %vfun(%struct.A* %0) #1
83
84  br label %if.end
85
86if.else:                                          ; preds = %entry
87  %vfn47 = getelementptr inbounds i8*, i8** %vtable, i64 1
88  %vfn4 = bitcast i8** %vfn47 to i32 (%struct.A*)**
89
90  ; CHECK: call i32 @_ZN1A3barEv(
91  %3 = load i32 (%struct.A*)*, i32 (%struct.A*)** %vfn4, align 8
92
93  %call5 = tail call i32 %3(%struct.A* %0) #1
94  br label %if.end
95
96if.end:                                           ; preds = %if.else, %if.then
97  ret void
98}
99
100
101; Checking const propagation in the same BB
102; CHECK-LABEL: define i32 @main()
103
104define i32 @main() {
105entry:
106  %call = tail call noalias i8* @_Znwm(i64 8)
107  %0 = bitcast i8* %call to %struct.A*
108  tail call void @_ZN1AC1Ev(%struct.A* %0)
109  %1 = bitcast i8* %call to i8***
110  %vtable = load i8**, i8*** %1, align 8
111  %cmp.vtables = icmp eq i8** %vtable, getelementptr inbounds ([4 x i8*], [4 x i8*]* @_ZTV1A, i64 0, i64 2)
112  tail call void @llvm.assume(i1 %cmp.vtables)
113  %vtable1.cast = bitcast i8** %vtable to i32 (%struct.A*)**
114
115  ; CHECK: call i32 @_ZN1A3fooEv(
116  %2 = load i32 (%struct.A*)*, i32 (%struct.A*)** %vtable1.cast, align 8
117
118  %call2 = tail call i32 %2(%struct.A* %0)
119  ret i32 0
120}
121
122; This tests checks const propatation with fcmp instruction.
123; CHECK-LABEL: define float @_Z1gf(float %p)
124
125define float @_Z1gf(float %p) {
126entry:
127  %p.addr = alloca float, align 4
128  %f = alloca float, align 4
129  store float %p, float* %p.addr, align 4
130
131  store float 3.000000e+00, float* %f, align 4
132  %0 = load float, float* %p.addr, align 4
133  %1 = load float, float* %f, align 4
134  %cmp = fcmp oeq float %1, %0 ; note const on lhs
135  call void @llvm.assume(i1 %cmp)
136
137  ; CHECK: ret float 3.000000e+00
138  ret float %0
139}
140
141; CHECK-LABEL: define float @_Z1hf(float %p)
142
143define float @_Z1hf(float %p) {
144entry:
145  %p.addr = alloca float, align 4
146  store float %p, float* %p.addr, align 4
147
148  %0 = load float, float* %p.addr, align 4
149  %cmp = fcmp nnan ueq float %0, 3.000000e+00
150  call void @llvm.assume(i1 %cmp)
151
152  ; CHECK: ret float 3.000000e+00
153  ret float %0
154}
155
156; CHECK-LABEL: define float @_Z1if(float %p)
157define float @_Z1if(float %p) {
158entry:
159  %p.addr = alloca float, align 4
160  store float %p, float* %p.addr, align 4
161
162  %0 = load float, float* %p.addr, align 4
163  %cmp = fcmp ueq float %0, 3.000000e+00 ; no nnan flag - can't propagate
164  call void @llvm.assume(i1 %cmp)
165
166  ; CHECK-NOT: ret float 3.000000e+00
167  ret float %0
168}
169
170; This test checks if constant propagation works for multiple node edges
171; CHECK-LABEL: define i32 @_Z1ii(i32 %p)
172define i32 @_Z1ii(i32 %p) {
173entry:
174  %cmp = icmp eq i32 %p, 42
175  call void @llvm.assume(i1 %cmp)
176
177  ; CHECK: br i1 true, label %bb2, label %bb2
178  br i1 %cmp, label %bb2, label %bb2
179bb2:
180  call void @llvm.assume(i1 true)
181  ; CHECK: br i1 true, label %bb2, label %bb2
182  br i1 %cmp, label %bb2, label %bb2
183
184  ; CHECK: ret i32 42
185  ret i32 %p
186}
187
188; CHECK-LABEL: define i32 @_Z1ij(i32 %p)
189define i32 @_Z1ij(i32 %p) {
190entry:
191  %cmp = icmp eq i32 %p, 42
192  call void @llvm.assume(i1 %cmp)
193
194  ; CHECK: br i1 true, label %bb2, label %bb2
195  br i1 %cmp, label %bb2, label %bb2
196bb2:
197   ; CHECK-NOT: %cmp2 =
198  %cmp2 = icmp eq i32 %p, 42
199  ; CHECK-NOT: call void @llvm.assume(
200  call void @llvm.assume(i1 %cmp2)
201
202  ; CHECK: br i1 true, label %bb2, label %bb2
203  br i1 %cmp, label %bb2, label %bb2
204
205  ; CHECK: ret i32 42
206  ret i32 %p
207}
208
209; CHECK-LABEL: define i32 @_Z1ik(i32 %p)
210define i32 @_Z1ik(i32 %p) {
211entry:
212  %cmp = icmp eq i32 %p, 42
213  call void @llvm.assume(i1 %cmp)
214
215  ; CHECK: br i1 true, label %bb2, label %bb3
216  br i1 %cmp, label %bb2, label %bb3
217bb2:
218  ; CHECK-NOT: %cmp3 =
219  %cmp3 = icmp eq i32 %p, 43
220  ; CHECK: store i8 undef, i8* null
221  call void @llvm.assume(i1 %cmp3)
222  ret i32 15
223bb3:
224  ret i32 17
225}
226
227; This test checks if GVN can do the constant propagation correctly
228; when there are multiple uses of the same assume value in the
229; basic block that has a loop back-edge pointing to itself.
230;
231; CHECK-LABEL: define i32 @_Z1il(i32 %val, i1 %k)
232define i32 @_Z1il(i32 %val, i1 %k) {
233  br label %next
234
235next:
236; CHECK: tail call void @llvm.assume(i1 %k)
237; CHECK-NEXT: %cmp = icmp eq i32 %val, 50
238  tail call void @llvm.assume(i1 %k)
239  tail call void @llvm.assume(i1 %k)
240  %cmp = icmp eq i32 %val, 50
241  br i1 %cmp, label %next, label %meh
242
243meh:
244  ret i32 0
245}
246
247; This test checks if GVN can prevent the constant propagation correctly
248; in the successor blocks that are not dominated by the basic block
249; with the assume instruction.
250;
251; CHECK-LABEL: define i1 @_z1im(i32 %val, i1 %k, i1 %j)
252define i1 @_z1im(i32 %val, i1 %k, i1 %j) {
253  br i1 %j, label %next, label %meh
254
255next:
256; CHECK: tail call void @llvm.assume(i1 %k)
257; CHECK-NEXT: br label %meh
258  tail call void @llvm.assume(i1 %k)
259  tail call void @llvm.assume(i1 %k)
260  br label %meh
261
262meh:
263; CHECK: ret i1 %k
264  ret i1 %k
265}
266
267declare noalias i8* @_Znwm(i64)
268declare void @_ZN1AC1Ev(%struct.A*)
269declare void @llvm.assume(i1)
270declare i32 @_ZN1A3fooEv(%struct.A*)
271declare i32 @_ZN1A3barEv(%struct.A*)
272
273!0 = !{!"struct A"}
274