1 // RUN: %clang_cc1 -triple x86_64-unknown-linux -flto -flto-unit -fvirtual-function-elimination -fwhole-program-vtables -emit-llvm -o - %s | FileCheck %s
2 // RUN: %clang -target x86_64-unknown-linux -flto -fvirtual-function-elimination -fno-virtual-function-elimination -fwhole-program-vtables -S -emit-llvm -o - %s | FileCheck %s -check-prefix=NOVFE
3
4 struct __attribute__((visibility("default"))) A {
5 virtual void foo();
6 };
7
test_1(A * p)8 void test_1(A *p) {
9 // A has default visibility, so no need for type.checked.load.
10 // CHECK-LABEL: define{{.*}} void @_Z6test_1P1A
11 // NOVFE-LABEL: define dso_local void @_Z6test_1P1A
12 // CHECK: [[FN_PTR_ADDR:%.+]] = getelementptr inbounds void (%struct.A*)*, void (%struct.A*)** {{%.+}}, i64 0
13 // NOVFE: [[FN_PTR_ADDR:%.+]] = getelementptr inbounds void (%struct.A*)*, void (%struct.A*)** {{%.+}}, i64 0
14 // CHECK: [[FN_PTR:%.+]] = load void (%struct.A*)*, void (%struct.A*)** [[FN_PTR_ADDR]]
15 // NOVFE: [[FN_PTR:%.+]] = load void (%struct.A*)*, void (%struct.A*)** [[FN_PTR_ADDR]]
16 // CHECK: call void [[FN_PTR]](
17 // NOVFE: call void [[FN_PTR]](
18 p->foo();
19 }
20
21
22 struct __attribute__((visibility("hidden"))) [[clang::lto_visibility_public]] B {
23 virtual void foo();
24 };
25
test_2(B * p)26 void test_2(B *p) {
27 // B has public LTO visibility, so no need for type.checked.load.
28 // CHECK-LABEL: define{{.*}} void @_Z6test_2P1B
29 // NOVFE-LABEL: define dso_local void @_Z6test_2P1B
30 // CHECK: [[FN_PTR_ADDR:%.+]] = getelementptr inbounds void (%struct.B*)*, void (%struct.B*)** {{%.+}}, i64 0
31 // NOVFE: [[FN_PTR_ADDR:%.+]] = getelementptr inbounds void (%struct.B*)*, void (%struct.B*)** {{%.+}}, i64 0
32 // CHECK: [[FN_PTR:%.+]] = load void (%struct.B*)*, void (%struct.B*)** [[FN_PTR_ADDR]]
33 // NOVFE: [[FN_PTR:%.+]] = load void (%struct.B*)*, void (%struct.B*)** [[FN_PTR_ADDR]]
34 // CHECK: call void [[FN_PTR]](
35 // NOVFE: call void [[FN_PTR]](
36 p->foo();
37 }
38
39
40 struct __attribute__((visibility("hidden"))) C {
41 virtual void foo();
42 virtual void bar();
43 };
44
test_3(C * p)45 void test_3(C *p) {
46 // C has hidden visibility, so we generate type.checked.load to allow VFE.
47 // CHECK-LABEL: define{{.*}} void @_Z6test_3P1C
48 // NOVFE-LABEL: define dso_local void @_Z6test_3P1C
49 // CHECK: [[LOAD:%.+]] = call { i8*, i1 } @llvm.type.checked.load(i8* {{%.+}}, i32 0, metadata !"_ZTS1C")
50 // NOVFE: call i1 @llvm.type.test(i8* {{%.+}}, metadata !"_ZTS1C")
51 // CHECK: [[FN_PTR_I8:%.+]] = extractvalue { i8*, i1 } [[LOAD]], 0
52 // NOVFE: [[FN_PTR:%.+]] = load void (%struct.C*)*, void (%struct.C*)** {{%.+}}, align 8
53 // CHECK: [[FN_PTR:%.+]] = bitcast i8* [[FN_PTR_I8]] to void (%struct.C*)*
54 // CHECK: call void [[FN_PTR]](
55 // NOVFE: call void [[FN_PTR]](
56 p->foo();
57 }
58
test_4(C * p)59 void test_4(C *p) {
60 // When using type.checked.load, we pass the vtable offset to the intrinsic,
61 // rather than adding it to the pointer with a GEP.
62 // CHECK-LABEL: define{{.*}} void @_Z6test_4P1C
63 // NOVFE-LABEL: define dso_local void @_Z6test_4P1C
64 // CHECK: [[LOAD:%.+]] = call { i8*, i1 } @llvm.type.checked.load(i8* {{%.+}}, i32 8, metadata !"_ZTS1C")
65 // NOVFE: call i1 @llvm.type.test(i8* {{%.+}}, metadata !"_ZTS1C")
66 // CHECK: [[FN_PTR_I8:%.+]] = extractvalue { i8*, i1 } [[LOAD]], 0
67 // NOVFE: [[FN_PTR:%.+]] = load void (%struct.C*)*, void (%struct.C*)** {{%.+}}, align 8
68 // CHECK: [[FN_PTR:%.+]] = bitcast i8* [[FN_PTR_I8]] to void (%struct.C*)*
69 // CHECK: call void [[FN_PTR]](
70 // NOVFE: call void [[FN_PTR]](
71 p->bar();
72 }
73
test_5(C * p,void (C::* q)(void))74 void test_5(C *p, void (C::*q)(void)) {
75 // We also use type.checked.load for the virtual side of member function
76 // pointer calls. We use a GEP to calculate the address to load from and pass
77 // 0 as the offset to the intrinsic, because we know that the load must be
78 // from exactly the point marked by one of the function-type metadatas (in
79 // this case "_ZTSM1CFvvE.virtual"). If we passed the offset from the member
80 // function pointer to the intrinsic, this information would be lost. No
81 // codegen changes on the non-virtual side.
82 // CHECK-LABEL: define{{.*}} void @_Z6test_5P1CMS_FvvE(
83 // NOVFE-LABEL: define dso_local void @_Z6test_5P1CMS_FvvE(
84 // CHECK: [[FN_PTR_ADDR:%.+]] = getelementptr i8, i8* %vtable, i64 {{%.+}}
85 // CHECK: [[LOAD:%.+]] = call { i8*, i1 } @llvm.type.checked.load(i8* [[FN_PTR_ADDR]], i32 0, metadata !"_ZTSM1CFvvE.virtual")
86 // NOVFE-NOT: call { i8*, i1 } @llvm.type.checked.load(i8* {{%.+}}, i32 0, metadata !"_ZTSM1CFvvE.virtual")
87 // CHECK: [[FN_PTR_I8:%.+]] = extractvalue { i8*, i1 } [[LOAD]], 0
88 // CHECK: [[FN_PTR:%.+]] = bitcast i8* [[FN_PTR_I8]] to void (%struct.C*)*
89 // NOVFE: [[FN_PTR:%.+]] = load void (%struct.C*)*, void (%struct.C*)** {{%.+}}, align 8
90
91 // CHECK: [[PHI:%.+]] = phi void (%struct.C*)* {{.*}}[ [[FN_PTR]], {{.*}} ]
92 // NOVFE: [[PHI:%.+]] = phi void (%struct.C*)* {{.*}}[ [[FN_PTR]], {{.*}} ]
93 // CHECK: call void [[PHI]](
94 // NOVFE: call void [[PHI]](
95 (p->*q)();
96 }
97