| //===-- ForeignClassMetadataVisitor.h - foreign class metadata -*- C++ --*-===// |
| // |
| // This source file is part of the Swift.org open source project |
| // |
| // Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors |
| // Licensed under Apache License v2.0 with Runtime Library Exception |
| // |
| // See https://swift.org/LICENSE.txt for license information |
| // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // A CRTP class useful for laying out foreign class metadata. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef SWIFT_IRGEN_FOREIGNCLASSMETADATAVISITOR_H |
| #define SWIFT_IRGEN_FOREIGNCLASSMETADATAVISITOR_H |
| |
| #include "NominalMetadataVisitor.h" |
| |
| namespace swift { |
| namespace irgen { |
| |
| /// A CRTP layout class for foreign class metadata. |
| template <class Impl> |
| class ForeignClassMetadataVisitor |
| : public NominalMetadataVisitor<Impl> { |
| using super = NominalMetadataVisitor<Impl>; |
| protected: |
| ClassDecl *Target; |
| using super::asImpl; |
| public: |
| ForeignClassMetadataVisitor(IRGenModule &IGM, ClassDecl *target) |
| : super(IGM), Target(target) {} |
| |
| void layout() { |
| super::layout(); |
| asImpl().addNominalTypeDescriptor(); |
| asImpl().addSuperclass(); |
| asImpl().addReservedWord(); |
| } |
| |
| CanType getTargetType() const { |
| return Target->getDeclaredType()->getCanonicalType(); |
| } |
| }; |
| |
| /// An "implementation" of ForeignClassMetadataVisitor that just scans through |
| /// the metadata layout, maintaining the offset of the next field. |
| template <class Impl> |
| class ForeignClassMetadataScanner : public ForeignClassMetadataVisitor<Impl> { |
| using super = ForeignClassMetadataVisitor<Impl>; |
| |
| protected: |
| Size NextOffset = Size(0); |
| |
| ForeignClassMetadataScanner(IRGenModule &IGM, ClassDecl *target) |
| : super(IGM, target) {} |
| |
| public: |
| void addMetadataFlags() { addPointer(); } |
| void addValueWitnessTable() { addPointer(); } |
| void addNominalTypeDescriptor() { addPointer(); } |
| void addSuperclass() { addPointer(); } |
| void addReservedWord() { addPointer(); } |
| |
| private: |
| void addPointer() { |
| NextOffset += super::IGM.getPointerSize(); |
| } |
| }; |
| |
| } // end namespace irgen |
| } // end namespace swift |
| |
| #endif // SWIFT_IRGEN_FOREIGNCLASSMETADATAVISITOR_H |