llvm-project/clang/test/CodeGenCXX/devirtualize-virtual-function-calls.cpp

// RUN: %clang_cc1 %s -triple armv7-none-eabi -emit-llvm -o - | FileCheck %s

struct A {
  virtual void f();
  virtual void f_const() const;

  A h();
};

A g();

void f(A a, A *ap, A& ar) {
  // This should not be a virtual function call.
  
  // CHECK: call void @_ZN1A1fEv(%struct.A* %a)
  a.f();

  // CHECK: call void %  
  ap->f();

  // CHECK: call void %  
  ar.f();
  
  // CHECK: call void @_ZN1A1fEv
  A().f();

  // CHECK: call void @_ZN1A1fEv
  g().f();
  
  // CHECK: call void @_ZN1A1fEv
  a.h().f();

  // CHECK: call void @_ZNK1A7f_constEv
  a.f_const();

  // CHECK: call void @_ZN1A1fEv
  (a).f();
}

struct B {
  virtual void f();
  ~B();
  
  B h();
};


void f() {
  // CHECK: call void @_ZN1B1fEv
  B().f();
  
  // CHECK: call void @_ZN1B1fEv
  B().h().f();
}

namespace test2 {
  struct foo {
    virtual void f();
    virtual ~foo();
  };

  struct bar : public foo {
    virtual void f();
    virtual ~bar();
  };

  void f(bar *b) {
    // CHECK: call void @_ZN5test23foo1fEv
    // CHECK: call %"struct.test2::foo"* @_ZN5test23fooD1Ev
    b->foo::f();
    b->foo::~foo();
  }
}

namespace test3 {
  // Test that we don't crash in this case.
  struct B {
  };
  struct D : public B {
  };
  void f(D d) {
    // CHECK-LABEL: define void @_ZN5test31fENS_1DE
    d.B::~B();
  }
}

namespace test4 {
  struct Animal {
    virtual void eat();
  };
  struct Fish : Animal {
    virtual void eat();
  };
  struct Wrapper {
    Fish fish;
  };
  extern Wrapper *p;
  void test() {
    // CHECK: call void @_ZN5test44Fish3eatEv
    p->fish.eat();
  }
}