C++ QualType::isDestructedType方法代码示例

/// \brief Build scope information for a captured block literal variables.
void JumpScopeChecker::BuildScopeInformation(VarDecl *D, 
                                             const BlockDecl *BDecl, 
                                             unsigned &ParentScope) {
  // exclude captured __block variables; there's no destructor
  // associated with the block literal for them.
  if (D->hasAttr<BlocksAttr>())
    return;
  QualType T = D->getType();
  QualType::DestructionKind destructKind = T.isDestructedType();
  if (destructKind != QualType::DK_none) {
    std::pair<unsigned,unsigned> Diags;
    switch (destructKind) {
      case QualType::DK_cxx_destructor:
        Diags = ScopePair(diag::note_enters_block_captures_cxx_obj,
                          diag::note_exits_block_captures_cxx_obj);
        break;
      case QualType::DK_objc_strong_lifetime:
        Diags = ScopePair(diag::note_enters_block_captures_strong,
                          diag::note_exits_block_captures_strong);
        break;
      case QualType::DK_objc_weak_lifetime:
        Diags = ScopePair(diag::note_enters_block_captures_weak,
                          diag::note_exits_block_captures_weak);
        break;
      case QualType::DK_none:
        llvm_unreachable("non-lifetime captured variable");
    }
    SourceLocation Loc = D->getLocation();
    if (Loc.isInvalid())
      Loc = BDecl->getLocation();
    Scopes.push_back(GotoScope(ParentScope, 
                               Diags.first, Diags.second, Loc));
    ParentScope = Scopes.size()-1;
  }
}

bool CGCXXABI::requiresArrayCookie(const CXXDeleteExpr *expr,
                                   QualType elementType) {
  // If the class's usual deallocation function takes two arguments,
  // it needs a cookie.
  if (expr->doesUsualArrayDeleteWantSize())
    return true;

  return elementType.isDestructedType();
}

/// Emit code to cause the destruction of the given variable with
/// static storage duration.
static void EmitDeclDestroy(CodeGenFunction &CGF, const VarDecl &D,
                            ConstantAddress addr) {
  CodeGenModule &CGM = CGF.CGM;

  // FIXME:  __attribute__((cleanup)) ?
  
  QualType type = D.getType();
  QualType::DestructionKind dtorKind = type.isDestructedType();

  switch (dtorKind) {
  case QualType::DK_none:
    return;

  case QualType::DK_cxx_destructor:
    break;

  case QualType::DK_objc_strong_lifetime:
  case QualType::DK_objc_weak_lifetime:
    // We don't care about releasing objects during process teardown.
    assert(!D.getTLSKind() && "should have rejected this");
    return;
  }

  llvm::Constant *function;
  llvm::Constant *argument;

  // Special-case non-array C++ destructors, if they have the right signature.
  // Under some ABIs, destructors return this instead of void, and cannot be
  // passed directly to __cxa_atexit if the target does not allow this mismatch.
  const CXXRecordDecl *Record = type->getAsCXXRecordDecl();
  bool CanRegisterDestructor =
      Record && (!CGM.getCXXABI().HasThisReturn(
                     GlobalDecl(Record->getDestructor(), Dtor_Complete)) ||
                 CGM.getCXXABI().canCallMismatchedFunctionType());
  // If __cxa_atexit is disabled via a flag, a different helper function is
  // generated elsewhere which uses atexit instead, and it takes the destructor
  // directly.
  bool UsingExternalHelper = !CGM.getCodeGenOpts().CXAAtExit;
  if (Record && (CanRegisterDestructor || UsingExternalHelper)) {
    assert(!Record->hasTrivialDestructor());
    CXXDestructorDecl *dtor = Record->getDestructor();

    function = CGM.getAddrOfCXXStructor(dtor, StructorType::Complete);
    argument = llvm::ConstantExpr::getBitCast(
        addr.getPointer(), CGF.getTypes().ConvertType(type)->getPointerTo());

  // Otherwise, the standard logic requires a helper function.
  } else {
    function = CodeGenFunction(CGM)
        .generateDestroyHelper(addr, type, CGF.getDestroyer(dtorKind),
                               CGF.needsEHCleanup(dtorKind), &D);
    argument = llvm::Constant::getNullValue(CGF.Int8PtrTy);
  }

  CGM.getCXXABI().registerGlobalDtor(CGF, D, function, argument);
}

/// Emit code to cause the destruction of the given variable with
/// static storage duration.
static void EmitDeclDestroy(CodeGenFunction &CGF, const VarDecl &D,
                            llvm::Constant *addr) {
  CodeGenModule &CGM = CGF.CGM;

  // FIXME:  __attribute__((cleanup)) ?
  
  QualType type = D.getType();
  QualType::DestructionKind dtorKind = type.isDestructedType();

  switch (dtorKind) {
  case QualType::DK_none:
    return;

  case QualType::DK_cxx_destructor:
    break;

  case QualType::DK_objc_strong_lifetime:
  case QualType::DK_objc_weak_lifetime:
    // We don't care about releasing objects during process teardown.
    assert(!D.getTLSKind() && "should have rejected this");
    return;
  }

  llvm::Constant *function;
  llvm::Constant *argument;

  // Special-case non-array C++ destructors, where there's a function
  // with the right signature that we can just call.
  const CXXRecordDecl *record = nullptr;
  if (dtorKind == QualType::DK_cxx_destructor &&
      (record = type->getAsCXXRecordDecl())) {
    assert(!record->hasTrivialDestructor());
    CXXDestructorDecl *dtor = record->getDestructor();

    function = CGM.getAddrOfCXXStructor(dtor, StructorType::Complete);
    argument = llvm::ConstantExpr::getBitCast(
        addr, CGF.getTypes().ConvertType(type)->getPointerTo());

  // Otherwise, the standard logic requires a helper function.
  } else {
    function = CodeGenFunction(CGM)
        .generateDestroyHelper(addr, type, CGF.getDestroyer(dtorKind),
                               CGF.needsEHCleanup(dtorKind), &D);
    argument = llvm::Constant::getNullValue(CGF.Int8PtrTy);
  }

  if(CGM.getTarget().isByteAddressable())
    CGM.getCXXABI().registerGlobalDtor(CGF, D, function, argument);
}

/// Emit code to cause the destruction of the given variable with
/// static storage duration.
static void EmitDeclDestroy(CodeGenFunction &CGF, const VarDecl &D,
                            llvm::Constant *addr) {
  CodeGenModule &CGM = CGF.CGM;

  // FIXME:  __attribute__((cleanup)) ?
  
  QualType type = D.getType();
  QualType::DestructionKind dtorKind = type.isDestructedType();

  switch (dtorKind) {
  case QualType::DK_none:
    return;

  case QualType::DK_cxx_destructor:
    break;

  case QualType::DK_objc_strong_lifetime:
  case QualType::DK_objc_weak_lifetime:
    // We don't care about releasing objects during process teardown.
    return;
  }

  llvm::Constant *function;
  llvm::Constant *argument;

  // Special-case non-array C++ destructors, where there's a function
  // with the right signature that we can just call.
  const CXXRecordDecl *record = 0;
  if (dtorKind == QualType::DK_cxx_destructor &&
      (record = type->getAsCXXRecordDecl())) {
    assert(!record->hasTrivialDestructor());
    CXXDestructorDecl *dtor = record->getDestructor();

    function = CGM.GetAddrOfCXXDestructor(dtor, Dtor_Complete);
    argument = addr;

  // Otherwise, the standard logic requires a helper function.
  } else {
    function = CodeGenFunction(CGM).generateDestroyHelper(addr, type,
                                                  CGF.getDestroyer(dtorKind),
                                                  CGF.needsEHCleanup(dtorKind));
    argument = llvm::Constant::getNullValue(CGF.Int8PtrTy);
  }

  CGF.EmitCXXGlobalDtorRegistration(function, argument);
}

/// Emit code to cause the destruction of the given variable with
/// static storage duration.
static void EmitDeclDestroy(CodeGenFunction &CGF, const VarDecl &D,
                            ConstantAddress Addr) {
  // Honor __attribute__((no_destroy)) and bail instead of attempting
  // to emit a reference to a possibly nonexistent destructor, which
  // in turn can cause a crash. This will result in a global constructor
  // that isn't balanced out by a destructor call as intended by the
  // attribute. This also checks for -fno-c++-static-destructors and
  // bails even if the attribute is not present.
  if (D.isNoDestroy(CGF.getContext()))
    return;
  
  CodeGenModule &CGM = CGF.CGM;

  // FIXME:  __attribute__((cleanup)) ?

  QualType Type = D.getType();
  QualType::DestructionKind DtorKind = Type.isDestructedType();

  switch (DtorKind) {
  case QualType::DK_none:
    return;

  case QualType::DK_cxx_destructor:
    break;

  case QualType::DK_objc_strong_lifetime:
  case QualType::DK_objc_weak_lifetime:
  case QualType::DK_nontrivial_c_struct:
    // We don't care about releasing objects during process teardown.
    assert(!D.getTLSKind() && "should have rejected this");
    return;
  }

  llvm::FunctionCallee Func;
  llvm::Constant *Argument;

  // Special-case non-array C++ destructors, if they have the right signature.
  // Under some ABIs, destructors return this instead of void, and cannot be
  // passed directly to __cxa_atexit if the target does not allow this
  // mismatch.
  const CXXRecordDecl *Record = Type->getAsCXXRecordDecl();
  bool CanRegisterDestructor =
      Record && (!CGM.getCXXABI().HasThisReturn(
                     GlobalDecl(Record->getDestructor(), Dtor_Complete)) ||
                 CGM.getCXXABI().canCallMismatchedFunctionType());
  // If __cxa_atexit is disabled via a flag, a different helper function is
  // generated elsewhere which uses atexit instead, and it takes the destructor
  // directly.
  bool UsingExternalHelper = !CGM.getCodeGenOpts().CXAAtExit;
  if (Record && (CanRegisterDestructor || UsingExternalHelper)) {
    assert(!Record->hasTrivialDestructor());
    CXXDestructorDecl *Dtor = Record->getDestructor();

    Func = CGM.getAddrAndTypeOfCXXStructor(Dtor, StructorType::Complete);
    Argument = llvm::ConstantExpr::getBitCast(
        Addr.getPointer(), CGF.getTypes().ConvertType(Type)->getPointerTo());

  // Otherwise, the standard logic requires a helper function.
  } else {
    Func = CodeGenFunction(CGM)
           .generateDestroyHelper(Addr, Type, CGF.getDestroyer(DtorKind),
                                  CGF.needsEHCleanup(DtorKind), &D);
    Argument = llvm::Constant::getNullValue(CGF.Int8PtrTy);
  }

  CGM.getCXXABI().registerGlobalDtor(CGF, D, Func, Argument);
}

void AggExprEmitter::VisitInitListExpr(InitListExpr *E) {
#if 0
  // FIXME: Assess perf here?  Figure out what cases are worth optimizing here
  // (Length of globals? Chunks of zeroed-out space?).
  //
  // If we can, prefer a copy from a global; this is a lot less code for long
  // globals, and it's easier for the current optimizers to analyze.
  if (llvm::Constant* C = CGF.CGM.EmitConstantExpr(E, E->getType(), &CGF)) {
    llvm::GlobalVariable* GV =
    new llvm::GlobalVariable(CGF.CGM.getModule(), C->getType(), true,
                             llvm::GlobalValue::InternalLinkage, C, "");
    EmitFinalDestCopy(E, CGF.MakeAddrLValue(GV, E->getType()));
    return;
  }
#endif
  if (E->hadArrayRangeDesignator())
    CGF.ErrorUnsupported(E, "GNU array range designator extension");

  llvm::Value *DestPtr = Dest.getAddr();

  // Handle initialization of an array.
  if (E->getType()->isArrayType()) {
    llvm::PointerType *APType =
      cast<llvm::PointerType>(DestPtr->getType());
    llvm::ArrayType *AType =
      cast<llvm::ArrayType>(APType->getElementType());

    uint64_t NumInitElements = E->getNumInits();

    if (E->getNumInits() > 0) {
      QualType T1 = E->getType();
      QualType T2 = E->getInit(0)->getType();
      if (CGF.getContext().hasSameUnqualifiedType(T1, T2)) {
        EmitAggLoadOfLValue(E->getInit(0));
        return;
      }
    }

    uint64_t NumArrayElements = AType->getNumElements();
    assert(NumInitElements <= NumArrayElements);

    QualType elementType = E->getType().getCanonicalType();
    elementType = CGF.getContext().getQualifiedType(
                    cast<ArrayType>(elementType)->getElementType(),
                    elementType.getQualifiers() + Dest.getQualifiers());

    // DestPtr is an array*.  Construct an elementType* by drilling
    // down a level.
    llvm::Value *zero = llvm::ConstantInt::get(CGF.SizeTy, 0);
    llvm::Value *indices[] = { zero, zero };
    llvm::Value *begin =
      Builder.CreateInBoundsGEP(DestPtr, indices, "arrayinit.begin");

    // Exception safety requires us to destroy all the
    // already-constructed members if an initializer throws.
    // For that, we'll need an EH cleanup.
    QualType::DestructionKind dtorKind = elementType.isDestructedType();
    llvm::AllocaInst *endOfInit = 0;
    EHScopeStack::stable_iterator cleanup;
    llvm::Instruction *cleanupDominator = 0;
    if (CGF.needsEHCleanup(dtorKind)) {
      // In principle we could tell the cleanup where we are more
      // directly, but the control flow can get so varied here that it
      // would actually be quite complex.  Therefore we go through an
      // alloca.
      endOfInit = CGF.CreateTempAlloca(begin->getType(),
                                       "arrayinit.endOfInit");
      cleanupDominator = Builder.CreateStore(begin, endOfInit);
      CGF.pushIrregularPartialArrayCleanup(begin, endOfInit, elementType,
                                           CGF.getDestroyer(dtorKind));
      cleanup = CGF.EHStack.stable_begin();

    // Otherwise, remember that we didn't need a cleanup.
    } else {
      dtorKind = QualType::DK_none;
    }

    llvm::Value *one = llvm::ConstantInt::get(CGF.SizeTy, 1);

    // The 'current element to initialize'.  The invariants on this
    // variable are complicated.  Essentially, after each iteration of
    // the loop, it points to the last initialized element, except
    // that it points to the beginning of the array before any
    // elements have been initialized.
    llvm::Value *element = begin;

    // Emit the explicit initializers.
    for (uint64_t i = 0; i != NumInitElements; ++i) {
      // Advance to the next element.
      if (i > 0) {
        element = Builder.CreateInBoundsGEP(element, one, "arrayinit.element");

        // Tell the cleanup that it needs to destroy up to this
        // element.  TODO: some of these stores can be trivially
        // observed to be unnecessary.
        if (endOfInit) Builder.CreateStore(element, endOfInit);
      }

      LValue elementLV = CGF.MakeAddrLValue(element, elementType);
      EmitInitializationToLValue(E->getInit(i), elementLV);
//.........这里部分代码省略.........

llvm::Function *CGOpenMPRuntime::EmitOMPThreadPrivateVarDefinition(
    const VarDecl *VD, llvm::Value *VDAddr, SourceLocation Loc,
    bool PerformInit, CodeGenFunction *CGF) {
  VD = VD->getDefinition(CGM.getContext());
  if (VD && ThreadPrivateWithDefinition.count(VD) == 0) {
    ThreadPrivateWithDefinition.insert(VD);
    QualType ASTTy = VD->getType();

    llvm::Value *Ctor = nullptr, *CopyCtor = nullptr, *Dtor = nullptr;
    auto Init = VD->getAnyInitializer();
    if (CGM.getLangOpts().CPlusPlus && PerformInit) {
      // Generate function that re-emits the declaration's initializer into the
      // threadprivate copy of the variable VD
      CodeGenFunction CtorCGF(CGM);
      FunctionArgList Args;
      ImplicitParamDecl Dst(CGM.getContext(), /*DC=*/nullptr, SourceLocation(),
                            /*Id=*/nullptr, CGM.getContext().VoidPtrTy);
      Args.push_back(&Dst);

      auto &FI = CGM.getTypes().arrangeFreeFunctionDeclaration(
          CGM.getContext().VoidPtrTy, Args, FunctionType::ExtInfo(),
          /*isVariadic=*/false);
      auto FTy = CGM.getTypes().GetFunctionType(FI);
      auto Fn = CGM.CreateGlobalInitOrDestructFunction(
          FTy, ".__kmpc_global_ctor_.", Loc);
      CtorCGF.StartFunction(GlobalDecl(), CGM.getContext().VoidPtrTy, Fn, FI,
                            Args, SourceLocation());
      auto ArgVal = CtorCGF.EmitLoadOfScalar(
          CtorCGF.GetAddrOfLocalVar(&Dst),
          /*Volatile=*/false, CGM.PointerAlignInBytes,
          CGM.getContext().VoidPtrTy, Dst.getLocation());
      auto Arg = CtorCGF.Builder.CreatePointerCast(
          ArgVal,
          CtorCGF.ConvertTypeForMem(CGM.getContext().getPointerType(ASTTy)));
      CtorCGF.EmitAnyExprToMem(Init, Arg, Init->getType().getQualifiers(),
                               /*IsInitializer=*/true);
      ArgVal = CtorCGF.EmitLoadOfScalar(
          CtorCGF.GetAddrOfLocalVar(&Dst),
          /*Volatile=*/false, CGM.PointerAlignInBytes,
          CGM.getContext().VoidPtrTy, Dst.getLocation());
      CtorCGF.Builder.CreateStore(ArgVal, CtorCGF.ReturnValue);
      CtorCGF.FinishFunction();
      Ctor = Fn;
    }
    if (VD->getType().isDestructedType() != QualType::DK_none) {
      // Generate function that emits destructor call for the threadprivate copy
      // of the variable VD
      CodeGenFunction DtorCGF(CGM);
      FunctionArgList Args;
      ImplicitParamDecl Dst(CGM.getContext(), /*DC=*/nullptr, SourceLocation(),
                            /*Id=*/nullptr, CGM.getContext().VoidPtrTy);
      Args.push_back(&Dst);

      auto &FI = CGM.getTypes().arrangeFreeFunctionDeclaration(
          CGM.getContext().VoidTy, Args, FunctionType::ExtInfo(),
          /*isVariadic=*/false);
      auto FTy = CGM.getTypes().GetFunctionType(FI);
      auto Fn = CGM.CreateGlobalInitOrDestructFunction(
          FTy, ".__kmpc_global_dtor_.", Loc);
      DtorCGF.StartFunction(GlobalDecl(), CGM.getContext().VoidTy, Fn, FI, Args,
                            SourceLocation());
      auto ArgVal = DtorCGF.EmitLoadOfScalar(
          DtorCGF.GetAddrOfLocalVar(&Dst),
          /*Volatile=*/false, CGM.PointerAlignInBytes,
          CGM.getContext().VoidPtrTy, Dst.getLocation());
      DtorCGF.emitDestroy(ArgVal, ASTTy,
                          DtorCGF.getDestroyer(ASTTy.isDestructedType()),
                          DtorCGF.needsEHCleanup(ASTTy.isDestructedType()));
      DtorCGF.FinishFunction();
      Dtor = Fn;
    }
    // Do not emit init function if it is not required.
    if (!Ctor && !Dtor)
      return nullptr;

    llvm::Type *CopyCtorTyArgs[] = {CGM.VoidPtrTy, CGM.VoidPtrTy};
    auto CopyCtorTy =
        llvm::FunctionType::get(CGM.VoidPtrTy, CopyCtorTyArgs,
                                /*isVarArg=*/false)->getPointerTo();
    // Copying constructor for the threadprivate variable.
    // Must be NULL - reserved by runtime, but currently it requires that this
    // parameter is always NULL. Otherwise it fires assertion.
    CopyCtor = llvm::Constant::getNullValue(CopyCtorTy);
    if (Ctor == nullptr) {
      auto CtorTy = llvm::FunctionType::get(CGM.VoidPtrTy, CGM.VoidPtrTy,
                                            /*isVarArg=*/false)->getPointerTo();
      Ctor = llvm::Constant::getNullValue(CtorTy);
    }
    if (Dtor == nullptr) {
      auto DtorTy = llvm::FunctionType::get(CGM.VoidTy, CGM.VoidPtrTy,
                                            /*isVarArg=*/false)->getPointerTo();
      Dtor = llvm::Constant::getNullValue(DtorTy);
    }
    if (!CGF) {
      auto InitFunctionTy =
          llvm::FunctionType::get(CGM.VoidTy, /*isVarArg*/ false);
      auto InitFunction = CGM.CreateGlobalInitOrDestructFunction(
          InitFunctionTy, ".__omp_threadprivate_init_.");
      CodeGenFunction InitCGF(CGM);
      FunctionArgList ArgList;
//.........这里部分代码省略.........

bool MicrosoftCXXABI::requiresArrayCookie(const CXXDeleteExpr *expr,
                                   QualType elementType) {
  // Microsoft seems to completely ignore the possibility of a
  // two-argument usual deallocation function.
  return elementType.isDestructedType();
}