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// RUN: %clang_cc1 -no-opaque-pointers -fno-rtti -emit-llvm %s -o - -mconstructor-aliases -triple=i386-pc-win32 | FileCheck %s
// RUN: %clang_cc1 -no-opaque-pointers -fno-rtti -emit-llvm %s -o - -mconstructor-aliases -triple=i386-pc-win32 -fno-delete-null-pointer-checks | 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: %[[CHILD:.*]] = load %struct.ChildNoOverride
child->left();
}
void ChildOverride::left() {}
void call_right_no_override(ChildNoOverride *child) {
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
}
void ChildOverride::right() {
foo(this);
}
void call_right_override(ChildOverride *child) {
child->right();
// Ensure that `nonnull` and `dereferenceable(N)` are not emitted whether or not null is valid
//
// CHECK: %[[RIGHT:.*]] = getelementptr inbounds i8, i8* %[[CHILD_i8]], i32 4
// CHECK: %[[VFUN_VALUE:.*]] = load void (i8*)*, void (i8*)** %[[VFUN]]
// CHECK: call x86_thiscallcc void %[[VFUN_VALUE]](i8* noundef %[[RIGHT]])
}
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