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| // RUN: %clang_cc1 -fno-rtti -emit-llvm %s -o - -mconstructor-aliases -triple=i386-pc-win32 | FileCheck %s
struct Left {
virtual void left();
};
struct Right {
virtual void right();
};
struct ChildNoOverride : Left, Right {
};
struct ChildOverride : Left, Right {
virtual void left();
virtual void right();
};
extern "C" void foo(void *);
void call_left_no_override(ChildNoOverride *child) {
// CHECK-LABEL: define dso_local void @"?call_left_no_override
// CHECK: %[[CHILD:.*]] = load %struct.ChildNoOverride
child->left();
// Only need to cast 'this' to Left*.
// CHECK: %[[LEFT:.*]] = bitcast %struct.ChildNoOverride* %[[CHILD]] to %struct.Left*
// CHECK: %[[VFPTR:.*]] = bitcast %struct.Left* %[[LEFT]] to void (%struct.Left*)***
// CHECK: %[[VFTABLE:.*]] = load void (%struct.Left*)**, void (%struct.Left*)*** %[[VFPTR]]
// CHECK: %[[VFUN:.*]] = getelementptr inbounds void (%struct.Left*)*, void (%struct.Left*)** %[[VFTABLE]], i64 0
// CHECK: %[[VFUN_VALUE:.*]] = load void (%struct.Left*)*, void (%struct.Left*)** %[[VFUN]]
// CHECK: call x86_thiscallcc void %[[VFUN_VALUE]](%struct.Left* %[[LEFT]])
// CHECK: ret
}
void ChildOverride::left() {
// CHECK-LABEL: define dso_local x86_thiscallcc void @"?left@ChildOverride@@UAEXXZ"
// CHECK-SAME: (%struct.ChildOverride* %[[THIS:.*]])
//
// No need to adjust 'this' as the ChildOverride's layout begins with Left.
// CHECK: %[[THIS_ADDR:.*]] = alloca %struct.ChildOverride*, align 4
// CHECK: store %struct.ChildOverride* %[[THIS]], %struct.ChildOverride** %[[THIS_ADDR]], align 4
foo(this);
// CHECK: %[[THIS:.*]] = load %struct.ChildOverride*, %struct.ChildOverride** %[[THIS_ADDR]]
// CHECK: %[[THIS_i8:.*]] = bitcast %struct.ChildOverride* %[[THIS]] to i8*
// CHECK: call void @foo(i8* %[[THIS_i8]])
// CHECK: ret
}
void call_left_override(ChildOverride *child) {
// CHECK-LABEL: define dso_local void @"?call_left_override
// CHECK: %[[CHILD:.*]] = load %struct.ChildOverride
child->left();
// CHECK: %[[VFPTR:.*]] = bitcast %struct.ChildOverride* %[[CHILD]] to void (%struct.ChildOverride*)***
// CHECK: %[[VFTABLE:.*]] = load void (%struct.ChildOverride*)**, void (%struct.ChildOverride*)*** %[[VFPTR]]
// CHECK: %[[VFUN:.*]] = getelementptr inbounds void (%struct.ChildOverride*)*, void (%struct.ChildOverride*)** %[[VFTABLE]], i64 0
// CHECK: %[[VFUN_VALUE:.*]] = load void (%struct.ChildOverride*)*, void (%struct.ChildOverride*)** %[[VFUN]]
//
// CHECK: call x86_thiscallcc void %[[VFUN_VALUE]](%struct.ChildOverride* %[[CHILD]])
// CHECK: ret
}
void call_right_no_override(ChildNoOverride *child) {
// CHECK-LABEL: define dso_local void @"?call_right_no_override
// CHECK: %[[CHILD:.*]] = load %struct.ChildNoOverride
child->right();
// When calling a right base's virtual method, one needs to adjust 'this' at
// the caller site.
//
// CHECK: %[[CHILD_i8:.*]] = bitcast %struct.ChildNoOverride* %[[CHILD]] to i8*
// CHECK: %[[RIGHT_i8:.*]] = getelementptr inbounds i8, i8* %[[CHILD_i8]], i32 4
// CHECK: %[[RIGHT:.*]] = bitcast i8* %[[RIGHT_i8]] to %struct.Right*
//
// CHECK: %[[VFPTR:.*]] = bitcast %struct.Right* %[[RIGHT]] to void (%struct.Right*)***
// CHECK: %[[VFTABLE:.*]] = load void (%struct.Right*)**, void (%struct.Right*)*** %[[VFPTR]]
// CHECK: %[[VFUN:.*]] = getelementptr inbounds void (%struct.Right*)*, void (%struct.Right*)** %[[VFTABLE]], i64 0
// CHECK: %[[VFUN_VALUE:.*]] = load void (%struct.Right*)*, void (%struct.Right*)** %[[VFUN]]
// CHECK: call x86_thiscallcc void %[[VFUN_VALUE]](%struct.Right* %[[RIGHT]])
// CHECK: ret
}
void ChildOverride::right() {
// CHECK-LABEL: define dso_local x86_thiscallcc void @"?right@ChildOverride@@UAEXXZ"(i8*
//
// ChildOverride::right gets 'this' cast to Right* in ECX (i.e. this+4) so we
// need to adjust 'this' before use.
//
// CHECK: %[[THIS_STORE:.*]] = alloca %struct.ChildOverride*, align 4
// CHECK: %[[THIS_ADDR:.*]] = alloca %struct.ChildOverride*, align 4
// CHECK: %[[COERCE_VAL:.*]] = bitcast i8* %[[ECX:.*]] to %struct.ChildOverride*
// CHECK: store %struct.ChildOverride* %[[COERCE_VAL]], %struct.ChildOverride** %[[THIS_STORE]], align 4
// CHECK: %[[THIS_INIT:.*]] = load %struct.ChildOverride*, %struct.ChildOverride** %[[THIS_STORE]], align 4
// CHECK: store %struct.ChildOverride* %[[THIS_INIT]], %struct.ChildOverride** %[[THIS_ADDR]], align 4
// CHECK: %[[THIS_RELOAD:.*]] = load %struct.ChildOverride*, %struct.ChildOverride** %[[THIS_ADDR]]
// CHECK: %[[THIS_i8:.*]] = bitcast %struct.ChildOverride* %[[THIS_RELOAD]] to i8*
// CHECK: %[[THIS_ADJUSTED:.*]] = getelementptr inbounds i8, i8* %[[THIS_i8]], i32 -4
// CHECK: %[[THIS:.*]] = bitcast i8* %[[THIS_ADJUSTED]] to %struct.ChildOverride*
foo(this);
// CHECK: %[[THIS_PARAM:.*]] = bitcast %struct.ChildOverride* %[[THIS]] to i8*
// CHECK: call void @foo(i8* %[[THIS_PARAM]])
// CHECK: ret
}
void call_right_override(ChildOverride *child) {
// CHECK-LABEL: define dso_local void @"?call_right_override
// CHECK: %[[CHILD:.*]] = load %struct.ChildOverride
child->right();
// When calling a right child's virtual method, one needs to adjust 'this' at
// the caller site.
//
// CHECK: %[[CHILD_i8:.*]] = bitcast %struct.ChildOverride* %[[CHILD]] to i8*
// CHECK: %[[RIGHT:.*]] = getelementptr inbounds i8, i8* %[[CHILD_i8]], i32 4
//
// CHECK: %[[CHILD_i8:.*]] = bitcast %struct.ChildOverride* %[[CHILD]] to i8*
// CHECK: %[[VFPTR_i8:.*]] = getelementptr inbounds i8, i8* %[[CHILD_i8]], i32 4
// CHECK: %[[VFPTR:.*]] = bitcast i8* %[[VFPTR_i8]] to void (i8*)***
// CHECK: %[[VFTABLE:.*]] = load void (i8*)**, void (i8*)*** %[[VFPTR]]
// CHECK: %[[VFUN:.*]] = getelementptr inbounds void (i8*)*, void (i8*)** %[[VFTABLE]], i64 0
// CHECK: %[[VFUN_VALUE:.*]] = load void (i8*)*, void (i8*)** %[[VFUN]]
//
// CHECK: call x86_thiscallcc void %[[VFUN_VALUE]](i8* %[[RIGHT]])
// CHECK: ret
}
struct GrandchildOverride : ChildOverride {
virtual void right();
};
void GrandchildOverride::right() {
// CHECK-LABEL: define dso_local x86_thiscallcc void @"?right@GrandchildOverride@@UAEXXZ"(i8*
//
// CHECK: %[[THIS_STORE:.*]] = alloca %struct.GrandchildOverride*, align 4
// CHECK: %[[THIS_ADDR:.*]] = alloca %struct.GrandchildOverride*, align 4
// CHECK: %[[COERCE_VAL:.*]] = bitcast i8* %[[ECX:.*]] to %struct.GrandchildOverride*
// CHECK: store %struct.GrandchildOverride* %[[COERCE_VAL]], %struct.GrandchildOverride** %[[THIS_STORE]], align 4
// CHECK: %[[THIS_INIT:.*]] = load %struct.GrandchildOverride*, %struct.GrandchildOverride** %[[THIS_STORE]], align 4
// CHECK: store %struct.GrandchildOverride* %[[THIS_INIT]], %struct.GrandchildOverride** %[[THIS_ADDR]], align 4
// CHECK: %[[THIS_RELOAD:.*]] = load %struct.GrandchildOverride*, %struct.GrandchildOverride** %[[THIS_ADDR]]
// CHECK: %[[THIS_i8:.*]] = bitcast %struct.GrandchildOverride* %[[THIS_RELOAD]] to i8*
// CHECK: %[[THIS_ADJUSTED:.*]] = getelementptr inbounds i8, i8* %[[THIS_i8]], i32 -4
// CHECK: %[[THIS:.*]] = bitcast i8* %[[THIS_ADJUSTED]] to %struct.GrandchildOverride*
foo(this);
// CHECK: %[[THIS_PARAM:.*]] = bitcast %struct.GrandchildOverride* %[[THIS]] to i8*
// CHECK: call void @foo(i8* %[[THIS_PARAM]])
// CHECK: ret
}
void call_grandchild_right(GrandchildOverride *obj) {
// Just make sure we don't crash.
obj->right();
}
void emit_ctors() {
Left l;
// CHECK-LABEL: define {{.*}} @"??0Left@@QAE@XZ"
// CHECK-NOT: getelementptr
// CHECK: store i32 (...)** bitcast ({ [1 x i8*] }* @"??_7Left@@6B@" to i32 (...)**)
// CHECK: ret
Right r;
// CHECK-LABEL: define {{.*}} @"??0Right@@QAE@XZ"
// CHECK-NOT: getelementptr
// CHECK: store i32 (...)** bitcast ({ [1 x i8*] }* @"??_7Right@@6B@" to i32 (...)**)
// CHECK: ret
ChildOverride co;
// CHECK-LABEL: define {{.*}} @"??0ChildOverride@@QAE@XZ"
// CHECK: %[[THIS:.*]] = load %struct.ChildOverride*, %struct.ChildOverride**
// CHECK: %[[VFPTR:.*]] = bitcast %struct.ChildOverride* %[[THIS]] to i32 (...)***
// CHECK: store i32 (...)** bitcast ({ [1 x i8*] }* @"??_7ChildOverride@@6BLeft@@@" to i32 (...)**), i32 (...)*** %[[VFPTR]]
// CHECK: %[[THIS_i8:.*]] = bitcast %struct.ChildOverride* %[[THIS]] to i8*
// CHECK: %[[VFPTR_i8:.*]] = getelementptr inbounds i8, i8* %[[THIS_i8]], i32 4
// CHECK: %[[VFPTR:.*]] = bitcast i8* %[[VFPTR_i8]] to i32 (...)***
// CHECK: store i32 (...)** bitcast ({ [1 x i8*] }* @"??_7ChildOverride@@6BRight@@@" to i32 (...)**), i32 (...)*** %[[VFPTR]]
// CHECK: ret
GrandchildOverride gc;
// CHECK-LABEL: define {{.*}} @"??0GrandchildOverride@@QAE@XZ"
// CHECK: %[[THIS:.*]] = load %struct.GrandchildOverride*, %struct.GrandchildOverride**
// CHECK: %[[VFPTR:.*]] = bitcast %struct.GrandchildOverride* %[[THIS]] to i32 (...)***
// CHECK: store i32 (...)** bitcast ({ [1 x i8*] }* @"??_7GrandchildOverride@@6BLeft@@@" to i32 (...)**), i32 (...)*** %[[VFPTR]]
// CHECK: %[[THIS_i8:.*]] = bitcast %struct.GrandchildOverride* %[[THIS]] to i8*
// CHECK: %[[VFPTR_i8:.*]] = getelementptr inbounds i8, i8* %[[THIS_i8]], i32 4
// CHECK: %[[VFPTR:.*]] = bitcast i8* %[[VFPTR_i8]] to i32 (...)***
// CHECK: store i32 (...)** bitcast ({ [1 x i8*] }* @"??_7GrandchildOverride@@6BRight@@@" to i32 (...)**), i32 (...)*** %[[VFPTR]]
// CHECK: ret
}
struct LeftWithNonVirtualDtor {
virtual void left();
~LeftWithNonVirtualDtor();
};
struct AsymmetricChild : LeftWithNonVirtualDtor, Right {
virtual ~AsymmetricChild();
};
void call_asymmetric_child_complete_dtor() {
// CHECK-LABEL: define dso_local void @"?call_asymmetric_child_complete_dtor@@YAXXZ"
AsymmetricChild obj;
// CHECK: call x86_thiscallcc %struct.AsymmetricChild* @"??0AsymmetricChild@@QAE@XZ"(%struct.AsymmetricChild* %[[OBJ:.*]])
// CHECK-NOT: getelementptr
// CHECK: call x86_thiscallcc void @"??1AsymmetricChild@@UAE@XZ"(%struct.AsymmetricChild* %[[OBJ]])
// CHECK: ret
}
|