When we're emitting a constructor or destructor call from a delegating

constructor, retrieve our VTT parameter directly. Fixes PR14588 /
<rdar://problem/12867962>.

llvm-svn: 174042

clang/lib/CodeGen/CGClass.cpp

@@ -282,7 +282,8 @@ CodeGenFunction::GetAddressOfDerivedClass(llvm::Value *Value,
 /// GetVTTParameter - Return the VTT parameter that should be passed to a
 /// base constructor/destructor with virtual bases.
 static llvm::Value *GetVTTParameter(CodeGenFunction &CGF, GlobalDecl GD,
-                                    bool ForVirtualBase) {
+                                    bool ForVirtualBase,
+                                    bool Delegating) {
   if (!CodeGenVTables::needsVTTParameter(GD)) {
     // This constructor/destructor does not need a VTT parameter.
     return 0;
@@ -295,9 +296,12 @@ static llvm::Value *GetVTTParameter(CodeGenFunction &CGF, GlobalDecl GD,
 
   uint64_t SubVTTIndex;
 
+  if (Delegating) {
+    // If this is a delegating constructor call, just load the VTT.
+    return CGF.LoadCXXVTT();
+  } else if (RD == Base) {
     // If the record matches the base, this is the complete ctor/dtor
     // variant calling the base variant in a class with virtual bases.
-  if (RD == Base) {
     assert(!CodeGenVTables::needsVTTParameter(CGF.CurGD) &&
            "doing no-op VTT offset in base dtor/ctor?");
     assert(!ForVirtualBase && "Can't have same class as virtual base!");
@@ -344,7 +348,8 @@ namespace {
         CGF.GetAddressOfDirectBaseInCompleteClass(CGF.LoadCXXThis(),
                                                   DerivedClass, BaseClass,
                                                   BaseIsVirtual);
-      CGF.EmitCXXDestructorCall(D, Dtor_Base, BaseIsVirtual, Addr);
+      CGF.EmitCXXDestructorCall(D, Dtor_Base, BaseIsVirtual,
+                                /*Delegating=*/false, Addr);
     }
   };
 
@@ -537,7 +542,7 @@ namespace {
 
     void Emit(CodeGenFunction &CGF, Flags flags) {
       CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete, /*ForVirtualBase=*/false,
-                                V);
+                                /*Delegating=*/false, V);
     }
   };
 }
@@ -893,7 +898,7 @@ void CodeGenFunction::EmitDestructorBody(FunctionArgList &Args) {
   if (DtorType == Dtor_Deleting) {
     EnterDtorCleanups(Dtor, Dtor_Deleting);
     EmitCXXDestructorCall(Dtor, Dtor_Complete, /*ForVirtualBase=*/false,
-                          LoadCXXThis());
+                          /*Delegating=*/false, LoadCXXThis());
     PopCleanupBlock();
     return;
   }
@@ -923,7 +928,7 @@ void CodeGenFunction::EmitDestructorBody(FunctionArgList &Args) {
     if (!isTryBody &&
         CGM.getContext().getTargetInfo().getCXXABI().hasDestructorVariants()) {
       EmitCXXDestructorCall(Dtor, Dtor_Base, /*ForVirtualBase=*/false,
-                            LoadCXXThis());
+                            /*Delegating=*/false, LoadCXXThis());
       break;
     }
     // Fallthrough: act like we're in the base variant.
@@ -1188,7 +1193,7 @@ CodeGenFunction::EmitCXXAggrConstructorCall(const CXXConstructorDecl *ctor,
     }
 
     EmitCXXConstructorCall(ctor, Ctor_Complete, /*ForVirtualBase=*/ false,
-                           cur, argBegin, argEnd);
+                           /*Delegating=*/false, cur, argBegin, argEnd);
   }
 
   // Go to the next element.
@@ -1216,12 +1221,13 @@ void CodeGenFunction::destroyCXXObject(CodeGenFunction &CGF,
   const CXXDestructorDecl *dtor = record->getDestructor();
   assert(!dtor->isTrivial());
   CGF.EmitCXXDestructorCall(dtor, Dtor_Complete, /*for vbase*/ false,
-                            addr);
+                            /*Delegating=*/false, addr);
 }
 
 void
 CodeGenFunction::EmitCXXConstructorCall(const CXXConstructorDecl *D,
                                         CXXCtorType Type, bool ForVirtualBase,
+                                        bool Delegating,
                                         llvm::Value *This,
                                         CallExpr::const_arg_iterator ArgBeg,
                                         CallExpr::const_arg_iterator ArgEnd) {
@@ -1255,7 +1261,8 @@ CodeGenFunction::EmitCXXConstructorCall(const CXXConstructorDecl *D,
     return;
   }
 
-  llvm::Value *VTT = GetVTTParameter(*this, GlobalDecl(D, Type), ForVirtualBase);
+  llvm::Value *VTT = GetVTTParameter(*this, GlobalDecl(D, Type), ForVirtualBase,
+                                     Delegating);
   llvm::Value *Callee = CGM.GetAddrOfCXXConstructor(D, Type);
 
   // FIXME: Provide a source location here.
@@ -1331,7 +1338,8 @@ CodeGenFunction::EmitDelegateCXXConstructorCall(const CXXConstructorDecl *Ctor,
 
   // vtt
   if (llvm::Value *VTT = GetVTTParameter(*this, GlobalDecl(Ctor, CtorType),
-                                         /*ForVirtualBase=*/false)) {
+                                         /*ForVirtualBase=*/false,
+                                         /*Delegating=*/true)) {
     QualType VoidPP = getContext().getPointerType(getContext().VoidPtrTy);
     DelegateArgs.add(RValue::get(VTT), VoidPP);
 
@@ -1365,7 +1373,7 @@ namespace {
 
     void Emit(CodeGenFunction &CGF, Flags flags) {
       CGF.EmitCXXDestructorCall(Dtor, Type, /*ForVirtualBase=*/false,
-                                Addr);
+                                /*Delegating=*/true, Addr);
     }
   };
 }
@@ -1401,9 +1409,10 @@ CodeGenFunction::EmitDelegatingCXXConstructorCall(const CXXConstructorDecl *Ctor
 void CodeGenFunction::EmitCXXDestructorCall(const CXXDestructorDecl *DD,
                                             CXXDtorType Type,
                                             bool ForVirtualBase,
+                                            bool Delegating,
                                             llvm::Value *This) {
   llvm::Value *VTT = GetVTTParameter(*this, GlobalDecl(DD, Type), 
-                                     ForVirtualBase);
+                                     ForVirtualBase, Delegating);
   llvm::Value *Callee = 0;
   if (getLangOpts().AppleKext)
     Callee = BuildAppleKextVirtualDestructorCall(DD, Type, 
@@ -1427,7 +1436,8 @@ namespace {
 
     void Emit(CodeGenFunction &CGF, Flags flags) {
       CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete,
-                                /*ForVirtualBase=*/false, Addr);
+                                /*ForVirtualBase=*/false,
+                                /*Delegating=*/false, Addr);
     }
   };
 }

clang/lib/CodeGen/CGDecl.cpp

@@ -386,7 +386,9 @@ namespace {
       }
 
       CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete,
-                                /*ForVirtualBase=*/false, Loc);
+                                /*ForVirtualBase=*/false,
+                                /*Delegating=*/false,
+                                Loc);
 
       if (NRVO) CGF.EmitBlock(SkipDtorBB);
     }

clang/lib/CodeGen/CGExprCXX.cpp

@@ -485,11 +485,13 @@ CodeGenFunction::EmitCXXConstructExpr(const CXXConstructExpr *E,
   } else {
     CXXCtorType Type = Ctor_Complete;
     bool ForVirtualBase = false;
+    bool Delegating = false;
     
     switch (E->getConstructionKind()) {
      case CXXConstructExpr::CK_Delegating:
       // We should be emitting a constructor; GlobalDecl will assert this
       Type = CurGD.getCtorType();
+      Delegating = true;
       break;
 
      case CXXConstructExpr::CK_Complete:
@@ -505,7 +507,7 @@ CodeGenFunction::EmitCXXConstructExpr(const CXXConstructExpr *E,
     }
     
     // Call the constructor.
-    EmitCXXConstructorCall(CD, Type, ForVirtualBase, Dest.getAddr(),
+    EmitCXXConstructorCall(CD, Type, ForVirtualBase, Delegating, Dest.getAddr(),
                            E->arg_begin(), E->arg_end());
   }
 }
@@ -1425,7 +1427,9 @@ static void EmitObjectDelete(CodeGenFunction &CGF,
 
   if (Dtor)
     CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete,
-                              /*ForVirtualBase=*/false, Ptr);
+                              /*ForVirtualBase=*/false,
+                              /*Delegating=*/false,
+                              Ptr);
   else if (CGF.getLangOpts().ObjCAutoRefCount &&
            ElementType->isObjCLifetimeType()) {
     switch (ElementType.getObjCLifetime()) {

clang/lib/CodeGen/CodeGenFunction.h

@@ -1816,7 +1816,8 @@ public:
   void EmitDelegatingCXXConstructorCall(const CXXConstructorDecl *Ctor,
                                         const FunctionArgList &Args);
   void EmitCXXConstructorCall(const CXXConstructorDecl *D, CXXCtorType Type,
-                              bool ForVirtualBase, llvm::Value *This,
+                              bool ForVirtualBase, bool Delegating,
+                              llvm::Value *This,
                               CallExpr::const_arg_iterator ArgBeg,
                               CallExpr::const_arg_iterator ArgEnd);
   
@@ -1842,7 +1843,8 @@ public:
   static Destroyer destroyCXXObject;
 
   void EmitCXXDestructorCall(const CXXDestructorDecl *D, CXXDtorType Type,
-                             bool ForVirtualBase, llvm::Value *This);
+                             bool ForVirtualBase, bool Delegating,
+                             llvm::Value *This);
 
   void EmitNewArrayInitializer(const CXXNewExpr *E, QualType elementType,
                                llvm::Value *NewPtr, llvm::Value *NumElements);

clang/test/CodeGenCXX/cxx0x-delegating-ctors.cpp

@@ -65,3 +65,37 @@ namespace PR12890 {
 }
 // CHECK: define {{.*}} @_ZN7PR128901XC1Ei(%"class.PR12890::X"* %this, i32)
 // CHECK: call void @llvm.memset.p0i8.{{i32|i64}}(i8* {{.*}}, i8 0, {{i32|i64}} 4, i32 4, i1 false)
+
+namespace PR14588 {
+  void other();
+
+  class Base {
+  public:
+    Base() { squawk(); }
+    virtual ~Base() {}
+
+    virtual void squawk() { other(); }
+  };
+
+
+  class Foo : public virtual Base {
+  public:
+    Foo();
+    Foo(const void * inVoid);
+    virtual ~Foo() {}
+
+    virtual void squawk() { other(); }
+  };
+
+  // CHECK: define void @_ZN7PR145883FooC1Ev(%"class.PR14588::Foo"*
+  // CHECK: call void @_ZN7PR145883FooC1EPKv(
+  // CHECK: invoke void @_ZN7PR145885otherEv()
+  // CHECK: call void @_ZN7PR145883FooD1Ev
+  // CHECK: resume
+
+  Foo::Foo() : Foo(__null) { other(); }
+  Foo::Foo(const void *inVoid) {
+    squawk();
+  }
+
+}