clang/test/CodeGenCXX/vtable-linkage.cpp

   1 // RUN: %clang_cc1 %s -triple=x86_64-pc-linux -emit-llvm -o %t
   2 // RUN: %clang_cc1 %s -triple=x86_64-pc-linux -emit-llvm -std=c++03 -o %t.03
   3 // RUN: %clang_cc1 %s -triple=x86_64-pc-linux -emit-llvm -std=c++11 -o %t.11
   4 // RUN: %clang_cc1 %s -triple=x86_64-apple-darwin10 -disable-llvm-passes -O3 -emit-llvm -o %t.opt
   5 // RUN: FileCheck %s < %t
   6 // RUN: FileCheck %s < %t.03
   7 // RUN: FileCheck %s < %t.11
   8 // RUN: FileCheck --check-prefix=CHECK-OPT %s < %t.opt
   9
  10 namespace {
  11   struct A {
  12     virtual void f() { }
  13   };
  14 }
  15
  16 void f() { A b; }
  17
  18 struct B {
  19   B();
  20   virtual void f();
  21 };
  22
  23 B::B() { }
  24
  25 struct C : virtual B {
  26   C();
  27   virtual void f() { }
  28 };
  29
  30 C::C() { }
  31
  32 struct D {
  33   virtual void f();
  34 };
  35
  36 void D::f() { }
  37
  38 static struct : D { } e;
  39
  40 // Force 'e' to be constructed and therefore have a vtable defined.
  41 void use_e() {
  42   e.f();
  43 }
  44
  45 // The destructor is the key function.
  46 template<typename T>
  47 struct E {
  48   virtual ~E();
  49 };
  50
  51 template<typename T> E<T>::~E() { }
  52
  53 // Anchor is the key function
  54 template<>
  55 struct E<char> {
  56   virtual void anchor();
  57 };
  58
  59 void E<char>::anchor() { }
  60
  61 template struct E<short>;
  62 extern template struct E<int>;
  63
  64 void use_E() {
  65   E<int> ei;
  66   (void)ei;
  67   E<long> el;
  68   (void)el;
  69 }
  70
  71 // No key function
  72 template<typename T>
  73 struct F {
  74   virtual void foo() { }
  75 };
  76
  77 // No key function
  78 template<>
  79 struct F<char> {
  80   virtual void foo() { }
  81 };
  82
  83 template struct F<short>;
  84 extern template struct F<int>;
  85
  86 void use_F() {
  87   F<char> fc;
  88   fc.foo();
  89   F<int> fi;
  90   fi.foo();
  91   F<long> fl;
  92   (void)fl;
  93 }
  94
  95 // B has a key function that is not defined in this translation unit so its vtable
  96 // has external linkage.
  97 // CHECK-DAG: @_ZTV1B = external unnamed_addr constant
  98
  99 // C has no key function, so its vtable should have weak_odr linkage
 100 // and hidden visibility.
 101 // CHECK-DAG: @_ZTV1C = linkonce_odr unnamed_addr constant {{.*}}, comdat, align 8{{$}}
 102 // CHECK-DAG: @_ZTS1C = linkonce_odr constant {{.*}}, comdat, align 1{{$}}
 103 // CHECK-DAG: @_ZTI1C = linkonce_odr constant {{.*}}, comdat, align 8{{$}}
 104 // CHECK-DAG: @_ZTT1C = linkonce_odr unnamed_addr constant {{.*}}, comdat, align 8{{$}}
 105
 106 // D has a key function that is defined in this translation unit so its vtable is
 107 // defined in the translation unit.
 108 // CHECK-DAG: @_ZTV1D ={{.*}} unnamed_addr constant
 109 // CHECK-DAG: @_ZTS1D ={{.*}} constant
 110 // CHECK-DAG: @_ZTI1D ={{.*}} constant
 111
 112 // E<char> is an explicit specialization with a key function defined
 113 // in this translation unit, so its vtable should have external
 114 // linkage.
 115 // CHECK-DAG: @_ZTV1EIcE ={{.*}} unnamed_addr constant
 116 // CHECK-DAG: @_ZTS1EIcE ={{.*}} constant
 117 // CHECK-DAG: @_ZTI1EIcE ={{.*}} constant
 118
 119 // E<short> is an explicit template instantiation with a key function
 120 // defined in this translation unit, so its vtable should have
 121 // weak_odr linkage.
 122 // CHECK-DAG: @_ZTV1EIsE = weak_odr unnamed_addr constant {{.*}}, comdat,
 123 // CHECK-DAG: @_ZTS1EIsE = weak_odr constant {{.*}}, comdat, align 1{{$}}
 124 // CHECK-DAG: @_ZTI1EIsE = weak_odr constant {{.*}}, comdat, align 8{{$}}
 125
 126 // F<short> is an explicit template instantiation without a key
 127 // function, so its vtable should have weak_odr linkage
 128 // CHECK-DAG: @_ZTV1FIsE = weak_odr unnamed_addr constant {{.*}}, comdat,
 129 // CHECK-DAG: @_ZTS1FIsE = weak_odr constant {{.*}}, comdat, align 1{{$}}
 130 // CHECK-DAG: @_ZTI1FIsE = weak_odr constant {{.*}}, comdat, align 8{{$}}
 131
 132 // E<long> is an implicit template instantiation with a key function
 133 // defined in this translation unit, so its vtable should have
 134 // linkonce_odr linkage.
 135 // CHECK-DAG: @_ZTV1EIlE = linkonce_odr unnamed_addr constant {{.*}}, comdat,
 136 // CHECK-DAG: @_ZTS1EIlE = linkonce_odr constant {{.*}}, comdat, align 1{{$}}
 137 // CHECK-DAG: @_ZTI1EIlE = linkonce_odr constant {{.*}}, comdat, align 8{{$}}
 138
 139 // F<long> is an implicit template instantiation with no key function,
 140 // so its vtable should have linkonce_odr linkage.
 141 // CHECK-DAG: @_ZTV1FIlE = linkonce_odr unnamed_addr constant {{.*}}, comdat,
 142 // CHECK-DAG: @_ZTS1FIlE = linkonce_odr constant {{.*}}, comdat, align 1{{$}}
 143 // CHECK-DAG: @_ZTI1FIlE = linkonce_odr constant {{.*}}, comdat, align 8{{$}}
 144
 145 // F<int> is an explicit template instantiation declaration without a
 146 // key function, so its vtable should have external linkage.
 147 // CHECK-DAG: @_ZTV1FIiE = external unnamed_addr constant
 148 // CHECK-OPT-DAG: @_ZTV1FIiE = available_externally unnamed_addr constant
 149
 150 // E<int> is an explicit template instantiation declaration. It has a
 151 // key function is not instantiated, so we know that vtable definition
 152 // will be generated in TU where key function will be defined
 153 // so we can mark it as external (without optimizations) and
 154 // available_externally (with optimizations) because all of the inline
 155 // virtual functions have been emitted.
 156 // CHECK-DAG: @_ZTV1EIiE = external unnamed_addr constant
 157 // CHECK-OPT-DAG: @_ZTV1EIiE = available_externally unnamed_addr constant
 158
 159 // The anonymous struct for e has no linkage, so the vtable should have
 160 // internal linkage.
 161 // CHECK-DAG: @"_ZTV3$_0" = internal unnamed_addr constant
 162 // CHECK-DAG: @"_ZTS3$_0" = internal constant
 163 // CHECK-DAG: @"_ZTI3$_0" = internal constant
 164
 165 // The A vtable should have internal linkage since it is inside an anonymous
 166 // namespace.
 167 // CHECK-DAG: @_ZTVN12_GLOBAL__N_11AE = internal unnamed_addr constant
 168 // CHECK-DAG: @_ZTSN12_GLOBAL__N_11AE = internal constant
 169 // CHECK-DAG: @_ZTIN12_GLOBAL__N_11AE = internal constant
 170
 171 // F<char> is an explicit specialization without a key function, so
 172 // its vtable should have linkonce_odr linkage.
 173 // CHECK-DAG: @_ZTV1FIcE = linkonce_odr unnamed_addr constant {{.*}}, comdat,
 174 // CHECK-DAG: @_ZTS1FIcE = linkonce_odr constant {{.*}}, comdat, align 1{{$}}
 175 // CHECK-DAG: @_ZTI1FIcE = linkonce_odr constant {{.*}}, comdat, align 8{{$}}
 176
 177 // CHECK-DAG: @_ZTV1GIiE = linkonce_odr unnamed_addr constant {{.*}}, comdat,
 178 template <typename T>
 179 class G {
 180 public:
 181   G() {}
 182   virtual void f0();
 183   virtual void f1();
 184 };
 185 template <>
 186 void G<int>::f1() {}
 187 template <typename T>
 188 void G<T>::f0() {}
 189 void G_f0()  { new G<int>(); }
 190
 191 // H<int> has a key function without a body but it's a template instantiation
 192 // so its VTable must be emitted.
 193 // CHECK-DAG: @_ZTV1HIiE = linkonce_odr unnamed_addr constant {{.*}}, comdat,
 194 template <typename T>
 195 class H {
 196 public:
 197   virtual ~H();
 198 };
 199
 200 void use_H() {
 201   H<int> h;
 202 }
 203
 204 // I<int> has an explicit instantiation declaration and needs a VTT and
 205 // construction vtables.
 206
 207 // CHECK-DAG: @_ZTV1IIiE = external unnamed_addr constant
 208 // CHECK-DAG: @_ZTT1IIiE = external unnamed_addr constant
 209 // CHECK-NOT: @_ZTC1IIiE
 210 //
 211 // CHECK-OPT-DAG: @_ZTV1IIiE = available_externally unnamed_addr constant
 212 // CHECK-OPT-DAG: @_ZTT1IIiE = available_externally unnamed_addr constant
 213 struct VBase1 { virtual void f(); }; struct VBase2 : virtual VBase1 {};
 214 template<typename T>
 215 struct I : VBase2 {};
 216 extern template struct I<int>;
 217 I<int> i;