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| // RUN: %clang_cc1 %s -fno-rtti -triple=i386-pc-win32 -emit-llvm -o %t.ll -fdump-vtable-layouts >%t
// RUN: FileCheck %s < %t
// RUN: FileCheck --check-prefix=BITCODE %s < %t.ll
namespace test1 {
struct A {
virtual void g();
// Add an extra virtual method so it's easier to check for the absence of thunks.
virtual void h();
};
struct B {
virtual void g(); // Collides with A::g if both are bases of some class.
};
// Overrides methods of two bases at the same time, thus needing thunks.
struct X : A, B {
// CHECK-LABEL: VFTable for 'test1::A' in 'test1::X' (2 entries).
// CHECK-NEXT: 0 | void test1::X::g()
// CHECK-NEXT: 1 | void test1::A::h()
// CHECK-LABEL: VFTable for 'test1::B' in 'test1::X' (1 entry).
// CHECK-NEXT: 0 | void test1::X::g()
// CHECK-NEXT: [this adjustment: -4 non-virtual]
// CHECK-LABEL: Thunks for 'void test1::X::g()' (1 entry).
// CHECK-NEXT: 0 | [this adjustment: -4 non-virtual]
// CHECK-LABEL: VFTable indices for 'test1::X' (1 entry).
// CHECK-NEXT: 0 | void test1::X::g()
// BITCODE-DAG: @"??_7X@test1@@6BA@1@@"
// BITCODE-DAG: @"??_7X@test1@@6BB@1@@"
virtual void g();
} x;
void build_vftable(X *obj) { obj->g(); }
}
namespace test2 {
struct A {
virtual void f();
};
struct B {
virtual void g();
virtual void h();
};
struct C {
virtual void g();
};
struct X : A, B, C {
// CHECK-LABEL: VFTable for 'test2::A' in 'test2::X' (1 entry).
// CHECK-NEXT: 0 | void test2::A::f()
// CHECK-LABEL: VFTable for 'test2::B' in 'test2::X' (2 entries).
// CHECK-NEXT: 0 | void test2::X::g()
// CHECK-NEXT: 1 | void test2::B::h()
// CHECK-LABEL: VFTable for 'test2::C' in 'test2::X' (1 entry).
// CHECK-NEXT: 0 | void test2::X::g()
// CHECK-NEXT: [this adjustment: -4 non-virtual]
// CHECK-LABEL: Thunks for 'void test2::X::g()' (1 entry).
// CHECK-NEXT: 0 | [this adjustment: -4 non-virtual]
// CHECK-LABEL: VFTable indices for 'test2::X' (1 entry).
// CHECK-NEXT: via vfptr at offset 4
// CHECK-NEXT: 0 | void test2::X::g()
// BITCODE-DAG: @"??_7X@test2@@6BA@1@@"
// BITCODE-DAG: @"??_7X@test2@@6BB@1@@"
// BITCODE-DAG: @"??_7X@test2@@6BC@1@@"
virtual void g();
} x;
void build_vftable(X *obj) { obj->g(); }
}
namespace test3 {
struct A {
virtual void f();
};
struct B {
virtual void g();
virtual void h();
};
struct C: A, B {
// Overrides only the left child's method (A::f), needs no thunks.
virtual void f();
};
struct D: A, B {
// Overrides only the right child's method (B::g),
// needs this adjustment but not thunks.
virtual void g();
};
// Overrides methods of two bases at the same time, thus needing thunks.
struct X: C, D {
// CHECK-LABEL: VFTable for 'test3::A' in 'test3::C' in 'test3::X' (1 entry).
// CHECK-NEXT: 0 | void test3::X::f()
// CHECK-LABEL: VFTable for 'test3::B' in 'test3::C' in 'test3::X' (2 entries).
// CHECK-NEXT: 0 | void test3::X::g()
// CHECK-NEXT: 1 | void test3::B::h()
// CHECK-LABEL: VFTable for 'test3::A' in 'test3::D' in 'test3::X' (1 entry).
// CHECK-NEXT: 0 | void test3::X::f()
// CHECK-NEXT: [this adjustment: -8 non-virtual]
// CHECK-LABEL: Thunks for 'void test3::X::f()' (1 entry).
// CHECK-NEXT: 0 | [this adjustment: -8 non-virtual]
// CHECK-LABEL: VFTable for 'test3::B' in 'test3::D' in 'test3::X' (2 entries).
// CHECK-NEXT: 0 | void test3::X::g()
// CHECK-NEXT: [this adjustment: -8 non-virtual]
// CHECK-NEXT: 1 | void test3::B::h()
// CHECK-LABEL: Thunks for 'void test3::X::g()' (1 entry).
// CHECK-NEXT: 0 | [this adjustment: -8 non-virtual]
// CHECK-LABEL: VFTable indices for 'test3::X' (2 entries).
// CHECK-NEXT: via vfptr at offset 0
// CHECK-NEXT: 0 | void test3::X::f()
// CHECK-NEXT: via vfptr at offset 4
// CHECK-NEXT: 0 | void test3::X::g()
virtual void f();
virtual void g();
} x;
void build_vftable(X *obj) { obj->g(); }
}
namespace test4 {
struct A {
virtual void foo();
};
struct B {
virtual int filler();
virtual int operator-();
virtual int bar();
};
struct C : public A, public B {
virtual int filler();
virtual int operator-();
virtual int bar();
};
// BITCODE-LABEL: define {{.*}}"?ffun@test4@@YAXAAUC@1@@Z
void ffun(C &c) {
// BITCODE: [[THIS1:%.+]] = bitcast %"struct.test4::C"* {{.*}} to i8*
// BITCODE: [[THIS2:%.+]] = getelementptr inbounds i8, i8* [[THIS1]], i32 4
// BITCODE: call x86_thiscallcc {{.*}}(i8* [[THIS2]])
c.bar();
}
// BITCODE-LABEL: define {{.*}}"?fop@test4@@YAXAAUC@1@@Z
void fop(C &c) {
// BITCODE: [[THIS1:%.+]] = bitcast %"struct.test4::C"* {{.*}} to i8*
// BITCODE: [[THIS2:%.+]] = getelementptr inbounds i8, i8* [[THIS1]], i32 4
// BITCODE: call x86_thiscallcc {{.*}}(i8* [[THIS2]])
-c;
}
}
namespace pr30293 {
struct NonTrivial {
~NonTrivial();
int x;
};
struct A { virtual void f(); };
struct B { virtual void __cdecl g(NonTrivial); };
struct C final : A, B {
void f() override;
void __cdecl g(NonTrivial) override;
};
C *whatsthis;
void C::f() { g(NonTrivial()); }
void C::g(NonTrivial o) {
whatsthis = this;
}
// BITCODE-LABEL: define dso_local void @"?g@C@pr30293@@UAAXUNonTrivial@2@@Z"(<{ i8*, %"struct.pr30293::NonTrivial" }>* inalloca %0)
// BITCODE: %[[thisaddr:[^ ]*]] = getelementptr inbounds <{ i8*, %"struct.pr30293::NonTrivial" }>, <{ i8*, %"struct.pr30293::NonTrivial" }>* {{.*}}, i32 0, i32 0
// BITCODE: %[[thisaddr1:[^ ]*]] = bitcast i8** %[[thisaddr]] to %"struct.pr30293::C"**
// BITCODE: %[[this1:[^ ]*]] = load %"struct.pr30293::C"*, %"struct.pr30293::C"** %[[thisaddr1]], align 4
// BITCODE: %[[this2:[^ ]*]] = bitcast %"struct.pr30293::C"* %[[this1]] to i8*
// BITCODE: %[[this3:[^ ]*]] = getelementptr inbounds i8, i8* %[[this2]], i32 -4
// BITCODE: %[[this4:[^ ]*]] = bitcast i8* %[[this3]] to %"struct.pr30293::C"*
// BITCODE: store %"struct.pr30293::C"* %[[this4]], %"struct.pr30293::C"** @"?whatsthis@pr30293@@3PAUC@1@A", align 4
}
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