723 lines
26 KiB
C++
723 lines
26 KiB
C++
//===- CXXInheritance.cpp - C++ Inheritance -------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file provides routines that help analyzing C++ inheritance hierarchies.
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//
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//===----------------------------------------------------------------------===//
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#include "clang/AST/CXXInheritance.h"
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#include "clang/AST/ASTContext.h"
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#include "clang/AST/Decl.h"
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#include "clang/AST/DeclBase.h"
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#include "clang/AST/DeclCXX.h"
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#include "clang/AST/DeclTemplate.h"
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#include "clang/AST/RecordLayout.h"
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#include "clang/AST/TemplateName.h"
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#include "clang/AST/Type.h"
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#include "clang/Basic/LLVM.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/STLExtras.h"
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#include "llvm/ADT/SetVector.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/ADT/iterator_range.h"
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#include "llvm/Support/Casting.h"
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#include <algorithm>
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#include <utility>
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#include <cassert>
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#include <vector>
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using namespace clang;
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/// isAmbiguous - Determines whether the set of paths provided is
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/// ambiguous, i.e., there are two or more paths that refer to
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/// different base class subobjects of the same type. BaseType must be
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/// an unqualified, canonical class type.
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bool CXXBasePaths::isAmbiguous(CanQualType BaseType) {
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BaseType = BaseType.getUnqualifiedType();
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IsVirtBaseAndNumberNonVirtBases Subobjects = ClassSubobjects[BaseType];
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return Subobjects.NumberOfNonVirtBases + (Subobjects.IsVirtBase ? 1 : 0) > 1;
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}
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/// clear - Clear out all prior path information.
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void CXXBasePaths::clear() {
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Paths.clear();
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ClassSubobjects.clear();
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VisitedDependentRecords.clear();
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ScratchPath.clear();
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DetectedVirtual = nullptr;
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}
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/// Swaps the contents of this CXXBasePaths structure with the
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/// contents of Other.
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void CXXBasePaths::swap(CXXBasePaths &Other) {
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std::swap(Origin, Other.Origin);
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Paths.swap(Other.Paths);
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ClassSubobjects.swap(Other.ClassSubobjects);
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VisitedDependentRecords.swap(Other.VisitedDependentRecords);
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std::swap(FindAmbiguities, Other.FindAmbiguities);
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std::swap(RecordPaths, Other.RecordPaths);
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std::swap(DetectVirtual, Other.DetectVirtual);
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std::swap(DetectedVirtual, Other.DetectedVirtual);
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}
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bool CXXRecordDecl::isDerivedFrom(const CXXRecordDecl *Base) const {
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CXXBasePaths Paths(/*FindAmbiguities=*/false, /*RecordPaths=*/false,
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/*DetectVirtual=*/false);
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return isDerivedFrom(Base, Paths);
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}
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bool CXXRecordDecl::isDerivedFrom(const CXXRecordDecl *Base,
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CXXBasePaths &Paths) const {
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if (getCanonicalDecl() == Base->getCanonicalDecl())
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return false;
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Paths.setOrigin(const_cast<CXXRecordDecl*>(this));
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const CXXRecordDecl *BaseDecl = Base->getCanonicalDecl();
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return lookupInBases(
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[BaseDecl](const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
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return FindBaseClass(Specifier, Path, BaseDecl);
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},
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Paths);
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}
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bool CXXRecordDecl::isVirtuallyDerivedFrom(const CXXRecordDecl *Base) const {
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if (!getNumVBases())
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return false;
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CXXBasePaths Paths(/*FindAmbiguities=*/false, /*RecordPaths=*/false,
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/*DetectVirtual=*/false);
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if (getCanonicalDecl() == Base->getCanonicalDecl())
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return false;
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Paths.setOrigin(const_cast<CXXRecordDecl*>(this));
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const CXXRecordDecl *BaseDecl = Base->getCanonicalDecl();
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return lookupInBases(
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[BaseDecl](const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
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return FindVirtualBaseClass(Specifier, Path, BaseDecl);
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},
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Paths);
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}
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bool CXXRecordDecl::isProvablyNotDerivedFrom(const CXXRecordDecl *Base) const {
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const CXXRecordDecl *TargetDecl = Base->getCanonicalDecl();
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return forallBases([TargetDecl](const CXXRecordDecl *Base) {
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return Base->getCanonicalDecl() != TargetDecl;
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});
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}
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bool
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CXXRecordDecl::isCurrentInstantiation(const DeclContext *CurContext) const {
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assert(isDependentContext());
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for (; !CurContext->isFileContext(); CurContext = CurContext->getParent())
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if (CurContext->Equals(this))
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return true;
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return false;
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}
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bool CXXRecordDecl::forallBases(ForallBasesCallback BaseMatches) const {
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SmallVector<const CXXRecordDecl*, 8> Queue;
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const CXXRecordDecl *Record = this;
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while (true) {
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for (const auto &I : Record->bases()) {
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const RecordType *Ty = I.getType()->getAs<RecordType>();
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if (!Ty)
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return false;
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CXXRecordDecl *Base =
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cast_or_null<CXXRecordDecl>(Ty->getDecl()->getDefinition());
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if (!Base ||
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(Base->isDependentContext() &&
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!Base->isCurrentInstantiation(Record))) {
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return false;
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}
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Queue.push_back(Base);
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if (!BaseMatches(Base))
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return false;
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}
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if (Queue.empty())
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break;
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Record = Queue.pop_back_val(); // not actually a queue.
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}
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return true;
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}
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bool CXXBasePaths::lookupInBases(ASTContext &Context,
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const CXXRecordDecl *Record,
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CXXRecordDecl::BaseMatchesCallback BaseMatches,
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bool LookupInDependent) {
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bool FoundPath = false;
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// The access of the path down to this record.
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AccessSpecifier AccessToHere = ScratchPath.Access;
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bool IsFirstStep = ScratchPath.empty();
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for (const auto &BaseSpec : Record->bases()) {
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// Find the record of the base class subobjects for this type.
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QualType BaseType =
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Context.getCanonicalType(BaseSpec.getType()).getUnqualifiedType();
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// C++ [temp.dep]p3:
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// In the definition of a class template or a member of a class template,
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// if a base class of the class template depends on a template-parameter,
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// the base class scope is not examined during unqualified name lookup
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// either at the point of definition of the class template or member or
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// during an instantiation of the class tem- plate or member.
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if (!LookupInDependent && BaseType->isDependentType())
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continue;
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// Determine whether we need to visit this base class at all,
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// updating the count of subobjects appropriately.
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IsVirtBaseAndNumberNonVirtBases &Subobjects = ClassSubobjects[BaseType];
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bool VisitBase = true;
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bool SetVirtual = false;
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if (BaseSpec.isVirtual()) {
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VisitBase = !Subobjects.IsVirtBase;
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Subobjects.IsVirtBase = true;
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if (isDetectingVirtual() && DetectedVirtual == nullptr) {
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// If this is the first virtual we find, remember it. If it turns out
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// there is no base path here, we'll reset it later.
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DetectedVirtual = BaseType->getAs<RecordType>();
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SetVirtual = true;
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}
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} else {
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++Subobjects.NumberOfNonVirtBases;
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}
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if (isRecordingPaths()) {
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// Add this base specifier to the current path.
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CXXBasePathElement Element;
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Element.Base = &BaseSpec;
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Element.Class = Record;
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if (BaseSpec.isVirtual())
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Element.SubobjectNumber = 0;
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else
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Element.SubobjectNumber = Subobjects.NumberOfNonVirtBases;
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ScratchPath.push_back(Element);
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// Calculate the "top-down" access to this base class.
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// The spec actually describes this bottom-up, but top-down is
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// equivalent because the definition works out as follows:
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// 1. Write down the access along each step in the inheritance
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// chain, followed by the access of the decl itself.
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// For example, in
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// class A { public: int foo; };
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// class B : protected A {};
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// class C : public B {};
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// class D : private C {};
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// we would write:
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// private public protected public
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// 2. If 'private' appears anywhere except far-left, access is denied.
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// 3. Otherwise, overall access is determined by the most restrictive
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// access in the sequence.
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if (IsFirstStep)
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ScratchPath.Access = BaseSpec.getAccessSpecifier();
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else
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ScratchPath.Access = CXXRecordDecl::MergeAccess(AccessToHere,
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BaseSpec.getAccessSpecifier());
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}
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// Track whether there's a path involving this specific base.
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bool FoundPathThroughBase = false;
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if (BaseMatches(&BaseSpec, ScratchPath)) {
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// We've found a path that terminates at this base.
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FoundPath = FoundPathThroughBase = true;
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if (isRecordingPaths()) {
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// We have a path. Make a copy of it before moving on.
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Paths.push_back(ScratchPath);
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} else if (!isFindingAmbiguities()) {
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// We found a path and we don't care about ambiguities;
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// return immediately.
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return FoundPath;
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}
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} else if (VisitBase) {
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CXXRecordDecl *BaseRecord;
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if (LookupInDependent) {
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BaseRecord = nullptr;
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const TemplateSpecializationType *TST =
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BaseSpec.getType()->getAs<TemplateSpecializationType>();
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if (!TST) {
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if (auto *RT = BaseSpec.getType()->getAs<RecordType>())
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BaseRecord = cast<CXXRecordDecl>(RT->getDecl());
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} else {
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TemplateName TN = TST->getTemplateName();
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if (auto *TD =
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dyn_cast_or_null<ClassTemplateDecl>(TN.getAsTemplateDecl()))
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BaseRecord = TD->getTemplatedDecl();
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}
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if (BaseRecord) {
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if (!BaseRecord->hasDefinition() ||
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VisitedDependentRecords.count(BaseRecord)) {
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BaseRecord = nullptr;
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} else {
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VisitedDependentRecords.insert(BaseRecord);
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}
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}
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} else {
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BaseRecord = cast<CXXRecordDecl>(
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BaseSpec.getType()->castAs<RecordType>()->getDecl());
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}
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if (BaseRecord &&
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lookupInBases(Context, BaseRecord, BaseMatches, LookupInDependent)) {
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// C++ [class.member.lookup]p2:
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// A member name f in one sub-object B hides a member name f in
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// a sub-object A if A is a base class sub-object of B. Any
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// declarations that are so hidden are eliminated from
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// consideration.
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// There is a path to a base class that meets the criteria. If we're
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// not collecting paths or finding ambiguities, we're done.
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FoundPath = FoundPathThroughBase = true;
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if (!isFindingAmbiguities())
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return FoundPath;
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}
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}
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// Pop this base specifier off the current path (if we're
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// collecting paths).
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if (isRecordingPaths()) {
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ScratchPath.pop_back();
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}
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// If we set a virtual earlier, and this isn't a path, forget it again.
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if (SetVirtual && !FoundPathThroughBase) {
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DetectedVirtual = nullptr;
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}
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}
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// Reset the scratch path access.
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ScratchPath.Access = AccessToHere;
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return FoundPath;
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}
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bool CXXRecordDecl::lookupInBases(BaseMatchesCallback BaseMatches,
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CXXBasePaths &Paths,
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bool LookupInDependent) const {
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// If we didn't find anything, report that.
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if (!Paths.lookupInBases(getASTContext(), this, BaseMatches,
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LookupInDependent))
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return false;
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// If we're not recording paths or we won't ever find ambiguities,
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// we're done.
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if (!Paths.isRecordingPaths() || !Paths.isFindingAmbiguities())
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return true;
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// C++ [class.member.lookup]p6:
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// When virtual base classes are used, a hidden declaration can be
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// reached along a path through the sub-object lattice that does
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// not pass through the hiding declaration. This is not an
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// ambiguity. The identical use with nonvirtual base classes is an
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// ambiguity; in that case there is no unique instance of the name
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// that hides all the others.
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//
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// FIXME: This is an O(N^2) algorithm, but DPG doesn't see an easy
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// way to make it any faster.
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Paths.Paths.remove_if([&Paths](const CXXBasePath &Path) {
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for (const CXXBasePathElement &PE : Path) {
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if (!PE.Base->isVirtual())
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continue;
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CXXRecordDecl *VBase = nullptr;
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if (const RecordType *Record = PE.Base->getType()->getAs<RecordType>())
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VBase = cast<CXXRecordDecl>(Record->getDecl());
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if (!VBase)
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break;
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// The declaration(s) we found along this path were found in a
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// subobject of a virtual base. Check whether this virtual
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// base is a subobject of any other path; if so, then the
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// declaration in this path are hidden by that patch.
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for (const CXXBasePath &HidingP : Paths) {
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CXXRecordDecl *HidingClass = nullptr;
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if (const RecordType *Record =
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HidingP.back().Base->getType()->getAs<RecordType>())
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HidingClass = cast<CXXRecordDecl>(Record->getDecl());
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if (!HidingClass)
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break;
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if (HidingClass->isVirtuallyDerivedFrom(VBase))
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return true;
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}
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}
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return false;
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});
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return true;
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}
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bool CXXRecordDecl::FindBaseClass(const CXXBaseSpecifier *Specifier,
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CXXBasePath &Path,
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const CXXRecordDecl *BaseRecord) {
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assert(BaseRecord->getCanonicalDecl() == BaseRecord &&
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"User data for FindBaseClass is not canonical!");
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return Specifier->getType()->castAs<RecordType>()->getDecl()
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->getCanonicalDecl() == BaseRecord;
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}
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bool CXXRecordDecl::FindVirtualBaseClass(const CXXBaseSpecifier *Specifier,
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CXXBasePath &Path,
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const CXXRecordDecl *BaseRecord) {
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assert(BaseRecord->getCanonicalDecl() == BaseRecord &&
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"User data for FindBaseClass is not canonical!");
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return Specifier->isVirtual() &&
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Specifier->getType()->castAs<RecordType>()->getDecl()
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->getCanonicalDecl() == BaseRecord;
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}
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static bool isOrdinaryMember(const NamedDecl *ND) {
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return ND->isInIdentifierNamespace(Decl::IDNS_Ordinary | Decl::IDNS_Tag |
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Decl::IDNS_Member);
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}
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static bool findOrdinaryMember(const CXXRecordDecl *RD, CXXBasePath &Path,
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DeclarationName Name) {
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Path.Decls = RD->lookup(Name);
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for (NamedDecl *ND : Path.Decls)
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if (isOrdinaryMember(ND))
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return true;
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return false;
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}
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bool CXXRecordDecl::hasMemberName(DeclarationName Name) const {
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CXXBasePath P;
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if (findOrdinaryMember(this, P, Name))
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return true;
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CXXBasePaths Paths(false, false, false);
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return lookupInBases(
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[Name](const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
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return findOrdinaryMember(Specifier->getType()->getAsCXXRecordDecl(),
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Path, Name);
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},
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Paths);
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}
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static bool
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findOrdinaryMemberInDependentClasses(const CXXBaseSpecifier *Specifier,
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CXXBasePath &Path, DeclarationName Name) {
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const TemplateSpecializationType *TST =
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Specifier->getType()->getAs<TemplateSpecializationType>();
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if (!TST) {
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auto *RT = Specifier->getType()->getAs<RecordType>();
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if (!RT)
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return false;
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return findOrdinaryMember(cast<CXXRecordDecl>(RT->getDecl()), Path, Name);
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}
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TemplateName TN = TST->getTemplateName();
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const auto *TD = dyn_cast_or_null<ClassTemplateDecl>(TN.getAsTemplateDecl());
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if (!TD)
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return false;
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CXXRecordDecl *RD = TD->getTemplatedDecl();
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if (!RD)
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return false;
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return findOrdinaryMember(RD, Path, Name);
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}
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std::vector<const NamedDecl *> CXXRecordDecl::lookupDependentName(
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DeclarationName Name,
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llvm::function_ref<bool(const NamedDecl *ND)> Filter) {
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std::vector<const NamedDecl *> Results;
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// Lookup in the class.
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bool AnyOrdinaryMembers = false;
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for (const NamedDecl *ND : lookup(Name)) {
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if (isOrdinaryMember(ND))
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AnyOrdinaryMembers = true;
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if (Filter(ND))
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Results.push_back(ND);
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}
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if (AnyOrdinaryMembers)
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return Results;
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// Perform lookup into our base classes.
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CXXBasePaths Paths;
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Paths.setOrigin(this);
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if (!lookupInBases(
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[&](const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
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return findOrdinaryMemberInDependentClasses(Specifier, Path, Name);
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},
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Paths, /*LookupInDependent=*/true))
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return Results;
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for (const NamedDecl *ND : Paths.front().Decls) {
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if (isOrdinaryMember(ND) && Filter(ND))
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Results.push_back(ND);
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}
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return Results;
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}
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void OverridingMethods::add(unsigned OverriddenSubobject,
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UniqueVirtualMethod Overriding) {
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SmallVectorImpl<UniqueVirtualMethod> &SubobjectOverrides
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= Overrides[OverriddenSubobject];
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if (llvm::find(SubobjectOverrides, Overriding) == SubobjectOverrides.end())
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SubobjectOverrides.push_back(Overriding);
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}
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void OverridingMethods::add(const OverridingMethods &Other) {
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for (const_iterator I = Other.begin(), IE = Other.end(); I != IE; ++I) {
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for (overriding_const_iterator M = I->second.begin(),
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MEnd = I->second.end();
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M != MEnd;
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++M)
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add(I->first, *M);
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}
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}
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void OverridingMethods::replaceAll(UniqueVirtualMethod Overriding) {
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for (iterator I = begin(), IEnd = end(); I != IEnd; ++I) {
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I->second.clear();
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I->second.push_back(Overriding);
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}
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}
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namespace {
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class FinalOverriderCollector {
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/// The number of subobjects of a given class type that
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/// occur within the class hierarchy.
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llvm::DenseMap<const CXXRecordDecl *, unsigned> SubobjectCount;
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/// Overriders for each virtual base subobject.
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llvm::DenseMap<const CXXRecordDecl *, CXXFinalOverriderMap *> VirtualOverriders;
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CXXFinalOverriderMap FinalOverriders;
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public:
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~FinalOverriderCollector();
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void Collect(const CXXRecordDecl *RD, bool VirtualBase,
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const CXXRecordDecl *InVirtualSubobject,
|
|
CXXFinalOverriderMap &Overriders);
|
|
};
|
|
|
|
} // namespace
|
|
|
|
void FinalOverriderCollector::Collect(const CXXRecordDecl *RD,
|
|
bool VirtualBase,
|
|
const CXXRecordDecl *InVirtualSubobject,
|
|
CXXFinalOverriderMap &Overriders) {
|
|
unsigned SubobjectNumber = 0;
|
|
if (!VirtualBase)
|
|
SubobjectNumber
|
|
= ++SubobjectCount[cast<CXXRecordDecl>(RD->getCanonicalDecl())];
|
|
|
|
for (const auto &Base : RD->bases()) {
|
|
if (const RecordType *RT = Base.getType()->getAs<RecordType>()) {
|
|
const CXXRecordDecl *BaseDecl = cast<CXXRecordDecl>(RT->getDecl());
|
|
if (!BaseDecl->isPolymorphic())
|
|
continue;
|
|
|
|
if (Overriders.empty() && !Base.isVirtual()) {
|
|
// There are no other overriders of virtual member functions,
|
|
// so let the base class fill in our overriders for us.
|
|
Collect(BaseDecl, false, InVirtualSubobject, Overriders);
|
|
continue;
|
|
}
|
|
|
|
// Collect all of the overridders from the base class subobject
|
|
// and merge them into the set of overridders for this class.
|
|
// For virtual base classes, populate or use the cached virtual
|
|
// overrides so that we do not walk the virtual base class (and
|
|
// its base classes) more than once.
|
|
CXXFinalOverriderMap ComputedBaseOverriders;
|
|
CXXFinalOverriderMap *BaseOverriders = &ComputedBaseOverriders;
|
|
if (Base.isVirtual()) {
|
|
CXXFinalOverriderMap *&MyVirtualOverriders = VirtualOverriders[BaseDecl];
|
|
BaseOverriders = MyVirtualOverriders;
|
|
if (!MyVirtualOverriders) {
|
|
MyVirtualOverriders = new CXXFinalOverriderMap;
|
|
|
|
// Collect may cause VirtualOverriders to reallocate, invalidating the
|
|
// MyVirtualOverriders reference. Set BaseOverriders to the right
|
|
// value now.
|
|
BaseOverriders = MyVirtualOverriders;
|
|
|
|
Collect(BaseDecl, true, BaseDecl, *MyVirtualOverriders);
|
|
}
|
|
} else
|
|
Collect(BaseDecl, false, InVirtualSubobject, ComputedBaseOverriders);
|
|
|
|
// Merge the overriders from this base class into our own set of
|
|
// overriders.
|
|
for (CXXFinalOverriderMap::iterator OM = BaseOverriders->begin(),
|
|
OMEnd = BaseOverriders->end();
|
|
OM != OMEnd;
|
|
++OM) {
|
|
const CXXMethodDecl *CanonOM = OM->first->getCanonicalDecl();
|
|
Overriders[CanonOM].add(OM->second);
|
|
}
|
|
}
|
|
}
|
|
|
|
for (auto *M : RD->methods()) {
|
|
// We only care about virtual methods.
|
|
if (!M->isVirtual())
|
|
continue;
|
|
|
|
CXXMethodDecl *CanonM = M->getCanonicalDecl();
|
|
using OverriddenMethodsRange =
|
|
llvm::iterator_range<CXXMethodDecl::method_iterator>;
|
|
OverriddenMethodsRange OverriddenMethods = CanonM->overridden_methods();
|
|
|
|
if (OverriddenMethods.begin() == OverriddenMethods.end()) {
|
|
// This is a new virtual function that does not override any
|
|
// other virtual function. Add it to the map of virtual
|
|
// functions for which we are tracking overridders.
|
|
|
|
// C++ [class.virtual]p2:
|
|
// For convenience we say that any virtual function overrides itself.
|
|
Overriders[CanonM].add(SubobjectNumber,
|
|
UniqueVirtualMethod(CanonM, SubobjectNumber,
|
|
InVirtualSubobject));
|
|
continue;
|
|
}
|
|
|
|
// This virtual method overrides other virtual methods, so it does
|
|
// not add any new slots into the set of overriders. Instead, we
|
|
// replace entries in the set of overriders with the new
|
|
// overrider. To do so, we dig down to the original virtual
|
|
// functions using data recursion and update all of the methods it
|
|
// overrides.
|
|
SmallVector<OverriddenMethodsRange, 4> Stack(1, OverriddenMethods);
|
|
while (!Stack.empty()) {
|
|
for (const CXXMethodDecl *OM : Stack.pop_back_val()) {
|
|
const CXXMethodDecl *CanonOM = OM->getCanonicalDecl();
|
|
|
|
// C++ [class.virtual]p2:
|
|
// A virtual member function C::vf of a class object S is
|
|
// a final overrider unless the most derived class (1.8)
|
|
// of which S is a base class subobject (if any) declares
|
|
// or inherits another member function that overrides vf.
|
|
//
|
|
// Treating this object like the most derived class, we
|
|
// replace any overrides from base classes with this
|
|
// overriding virtual function.
|
|
Overriders[CanonOM].replaceAll(
|
|
UniqueVirtualMethod(CanonM, SubobjectNumber,
|
|
InVirtualSubobject));
|
|
|
|
auto OverriddenMethods = CanonOM->overridden_methods();
|
|
if (OverriddenMethods.begin() == OverriddenMethods.end())
|
|
continue;
|
|
|
|
// Continue recursion to the methods that this virtual method
|
|
// overrides.
|
|
Stack.push_back(OverriddenMethods);
|
|
}
|
|
}
|
|
|
|
// C++ [class.virtual]p2:
|
|
// For convenience we say that any virtual function overrides itself.
|
|
Overriders[CanonM].add(SubobjectNumber,
|
|
UniqueVirtualMethod(CanonM, SubobjectNumber,
|
|
InVirtualSubobject));
|
|
}
|
|
}
|
|
|
|
FinalOverriderCollector::~FinalOverriderCollector() {
|
|
for (llvm::DenseMap<const CXXRecordDecl *, CXXFinalOverriderMap *>::iterator
|
|
VO = VirtualOverriders.begin(), VOEnd = VirtualOverriders.end();
|
|
VO != VOEnd;
|
|
++VO)
|
|
delete VO->second;
|
|
}
|
|
|
|
void
|
|
CXXRecordDecl::getFinalOverriders(CXXFinalOverriderMap &FinalOverriders) const {
|
|
FinalOverriderCollector Collector;
|
|
Collector.Collect(this, false, nullptr, FinalOverriders);
|
|
|
|
// Weed out any final overriders that come from virtual base class
|
|
// subobjects that were hidden by other subobjects along any path.
|
|
// This is the final-overrider variant of C++ [class.member.lookup]p10.
|
|
for (auto &OM : FinalOverriders) {
|
|
for (auto &SO : OM.second) {
|
|
SmallVectorImpl<UniqueVirtualMethod> &Overriding = SO.second;
|
|
if (Overriding.size() < 2)
|
|
continue;
|
|
|
|
auto IsHidden = [&Overriding](const UniqueVirtualMethod &M) {
|
|
if (!M.InVirtualSubobject)
|
|
return false;
|
|
|
|
// We have an overriding method in a virtual base class
|
|
// subobject (or non-virtual base class subobject thereof);
|
|
// determine whether there exists an other overriding method
|
|
// in a base class subobject that hides the virtual base class
|
|
// subobject.
|
|
for (const UniqueVirtualMethod &OP : Overriding)
|
|
if (&M != &OP &&
|
|
OP.Method->getParent()->isVirtuallyDerivedFrom(
|
|
M.InVirtualSubobject))
|
|
return true;
|
|
return false;
|
|
};
|
|
|
|
// FIXME: IsHidden reads from Overriding from the middle of a remove_if
|
|
// over the same sequence! Is this guaranteed to work?
|
|
Overriding.erase(
|
|
std::remove_if(Overriding.begin(), Overriding.end(), IsHidden),
|
|
Overriding.end());
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
AddIndirectPrimaryBases(const CXXRecordDecl *RD, ASTContext &Context,
|
|
CXXIndirectPrimaryBaseSet& Bases) {
|
|
// If the record has a virtual primary base class, add it to our set.
|
|
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
|
|
if (Layout.isPrimaryBaseVirtual())
|
|
Bases.insert(Layout.getPrimaryBase());
|
|
|
|
for (const auto &I : RD->bases()) {
|
|
assert(!I.getType()->isDependentType() &&
|
|
"Cannot get indirect primary bases for class with dependent bases.");
|
|
|
|
const CXXRecordDecl *BaseDecl =
|
|
cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl());
|
|
|
|
// Only bases with virtual bases participate in computing the
|
|
// indirect primary virtual base classes.
|
|
if (BaseDecl->getNumVBases())
|
|
AddIndirectPrimaryBases(BaseDecl, Context, Bases);
|
|
}
|
|
|
|
}
|
|
|
|
void
|
|
CXXRecordDecl::getIndirectPrimaryBases(CXXIndirectPrimaryBaseSet& Bases) const {
|
|
ASTContext &Context = getASTContext();
|
|
|
|
if (!getNumVBases())
|
|
return;
|
|
|
|
for (const auto &I : bases()) {
|
|
assert(!I.getType()->isDependentType() &&
|
|
"Cannot get indirect primary bases for class with dependent bases.");
|
|
|
|
const CXXRecordDecl *BaseDecl =
|
|
cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl());
|
|
|
|
// Only bases with virtual bases participate in computing the
|
|
// indirect primary virtual base classes.
|
|
if (BaseDecl->getNumVBases())
|
|
AddIndirectPrimaryBases(BaseDecl, Context, Bases);
|
|
}
|
|
}
|