1; RUN: opt < %s -passes=globaldce -S | FileCheck %s
2
3target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
4
5; struct A {
6;   A();
7;   virtual int foo(int);
8;   virtual int bar(float);
9; };
10;
11; struct B : A {
12;   B();
13;   virtual int foo(int);
14;   virtual int bar(float);
15; };
16;
17; A::A() {}
18; B::B() {}
19; int A::foo(int)   { return 1; }
20; int A::bar(float) { return 2; }
21; int B::foo(int)   { return 3; }
22; int B::bar(float) { return 4; }
23;
24; extern "C" int test(A *p, int (A::*q)(int)) { return (p->*q)(42); }
25
26; Member function pointers are tracked by the combination of their object type
27; and function type, which must both be compatible. Here, the call is through a
28; pointer of type "int (A::*q)(int)", so the call could be dispatched to A::foo
29; or B::foo. It can't be dispatched to A::bar or B::bar as the function pointer
30; does not match, so those can be removed.
31
32%struct.A = type { i32 (...)** }
33%struct.B = type { %struct.A }
34
35; CHECK: @_ZTV1A = internal unnamed_addr constant { [4 x i8*] } { [4 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.A*, i32)* @_ZN1A3fooEi to i8*), i8* null] }
36@_ZTV1A = internal unnamed_addr constant { [4 x i8*] } { [4 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.A*, i32)* @_ZN1A3fooEi to i8*), i8* bitcast (i32 (%struct.A*, float)* @_ZN1A3barEf to i8*)] }, align 8, !type !0, !type !1, !type !2, !vcall_visibility !3
37; CHECK: @_ZTV1B = internal unnamed_addr constant { [4 x i8*] } { [4 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.B*, i32)* @_ZN1B3fooEi to i8*), i8* null] }
38@_ZTV1B = internal unnamed_addr constant { [4 x i8*] } { [4 x i8*] [i8* null, i8* null, i8* bitcast (i32 (%struct.B*, i32)* @_ZN1B3fooEi to i8*), i8* bitcast (i32 (%struct.B*, float)* @_ZN1B3barEf to i8*)] }, align 8, !type !0, !type !1, !type !2, !type !4, !type !5, !type !6, !vcall_visibility !3
39
40
41; CHECK: define internal i32 @_ZN1A3fooEi(
42define internal i32 @_ZN1A3fooEi(%struct.A* nocapture readnone %this, i32) unnamed_addr #1 align 2 {
43entry:
44  ret i32 1
45}
46
47; CHECK-NOT: define internal i32 @_ZN1A3barEf(
48define internal i32 @_ZN1A3barEf(%struct.A* nocapture readnone %this, float) unnamed_addr #1 align 2 {
49entry:
50  ret i32 2
51}
52
53; CHECK: define internal i32 @_ZN1B3fooEi(
54define internal i32 @_ZN1B3fooEi(%struct.B* nocapture readnone %this, i32) unnamed_addr #1 align 2 {
55entry:
56  ret i32 3
57}
58
59; CHECK-NOT: define internal i32 @_ZN1B3barEf(
60define internal i32 @_ZN1B3barEf(%struct.B* nocapture readnone %this, float) unnamed_addr #1 align 2 {
61entry:
62  ret i32 4
63}
64
65
66define hidden void @_ZN1AC2Ev(%struct.A* nocapture %this) {
67entry:
68  %0 = getelementptr inbounds %struct.A, %struct.A* %this, i64 0, i32 0
69  store i32 (...)** bitcast (i8** getelementptr inbounds ({ [4 x i8*] }, { [4 x i8*] }* @_ZTV1A, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
70  ret void
71}
72
73define hidden void @_ZN1BC2Ev(%struct.B* nocapture %this) {
74entry:
75  %0 = getelementptr inbounds %struct.B, %struct.B* %this, i64 0, i32 0, i32 0
76  store i32 (...)** bitcast (i8** getelementptr inbounds ({ [4 x i8*] }, { [4 x i8*] }* @_ZTV1B, i64 0, inrange i32 0, i64 2) to i32 (...)**), i32 (...)*** %0, align 8
77  ret void
78}
79
80define hidden i32 @test(%struct.A* %p, i64 %q.coerce0, i64 %q.coerce1) {
81entry:
82  %0 = bitcast %struct.A* %p to i8*
83  %1 = getelementptr inbounds i8, i8* %0, i64 %q.coerce1
84  %this.adjusted = bitcast i8* %1 to %struct.A*
85  %2 = and i64 %q.coerce0, 1
86  %memptr.isvirtual = icmp eq i64 %2, 0
87  br i1 %memptr.isvirtual, label %memptr.nonvirtual, label %memptr.virtual
88
89memptr.virtual:                                   ; preds = %entry
90  %3 = bitcast i8* %1 to i8**
91  %vtable = load i8*, i8** %3, align 8
92  %4 = add i64 %q.coerce0, -1
93  %5 = getelementptr i8, i8* %vtable, i64 %4, !nosanitize !12
94  %6 = tail call { i8*, i1 } @llvm.type.checked.load(i8* %5, i32 0, metadata !"_ZTSM1AFiiE.virtual"), !nosanitize !12
95  %7 = extractvalue { i8*, i1 } %6, 0, !nosanitize !12
96  %memptr.virtualfn = bitcast i8* %7 to i32 (%struct.A*, i32)*, !nosanitize !12
97  br label %memptr.end
98
99memptr.nonvirtual:                                ; preds = %entry
100  %memptr.nonvirtualfn = inttoptr i64 %q.coerce0 to i32 (%struct.A*, i32)*
101  br label %memptr.end
102
103memptr.end:                                       ; preds = %memptr.nonvirtual, %memptr.virtual
104  %8 = phi i32 (%struct.A*, i32)* [ %memptr.virtualfn, %memptr.virtual ], [ %memptr.nonvirtualfn, %memptr.nonvirtual ]
105  %call = tail call i32 %8(%struct.A* %this.adjusted, i32 42)
106  ret i32 %call
107}
108
109declare { i8*, i1 } @llvm.type.checked.load(i8*, i32, metadata)
110
111!llvm.module.flags = !{!7}
112
113!0 = !{i64 16, !"_ZTS1A"}
114!1 = !{i64 16, !"_ZTSM1AFiiE.virtual"}
115!2 = !{i64 24, !"_ZTSM1AFifE.virtual"}
116!3 = !{i64 2}
117!4 = !{i64 16, !"_ZTS1B"}
118!5 = !{i64 16, !"_ZTSM1BFiiE.virtual"}
119!6 = !{i64 24, !"_ZTSM1BFifE.virtual"}
120!7 = !{i32 1, !"Virtual Function Elim", i32 1}
121!12 = !{}
122