| //===--- MetadataLayout.h - CRTP for metadata layout ------------*- C++ -*-===// |
| // |
| // This source file is part of the Swift.org open source project |
| // |
| // Copyright (c) 2014 - 2015 Apple Inc. and the Swift project authors |
| // Licensed under Apache License v2.0 with Runtime Library Exception |
| // |
| // See http://swift.org/LICENSE.txt for license information |
| // See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // A CRTP helper class for laying out type metadata. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef SWIFT_IRGEN_METADATALAYOUT_H |
| #define SWIFT_IRGEN_METADATALAYOUT_H |
| |
| #include "llvm/ADT/SmallVector.h" |
| #include "swift/AST/Decl.h" |
| #include "swift/SIL/TypeLowering.h" |
| #include "GenProto.h" |
| |
| namespace swift { |
| namespace irgen { |
| |
| class IRGenModule; |
| |
| /// A CRTP class for laying out type metadata. Note that this does |
| /// *not* handle the metadata template stuff. |
| template <class Impl> class MetadataLayout { |
| protected: |
| Impl &asImpl() { return *static_cast<Impl*>(this); } |
| |
| protected: |
| IRGenModule &IGM; |
| |
| MetadataLayout(IRGenModule &IGM) : IGM(IGM) {} |
| |
| public: |
| void layout() { |
| // Common fields. |
| asImpl().addValueWitnessTable(); |
| asImpl().noteAddressPoint(); |
| asImpl().addMetadataFlags(); |
| } |
| |
| /// This is the address point. |
| void noteAddressPoint() {} |
| |
| /// Add fields related to the generics of this class declaration. |
| /// TODO: don't add new fields that are implied by the superclass |
| /// fields. e.g., if B<T> extends A<T>, the witness for T in A's |
| /// section should be enough. |
| template <class... T> |
| void addGenericFields(const GenericParamList &generics, |
| T &&...args) { |
| // The archetype order here needs to be consistent with |
| // NominalTypeDescriptorBase::addGenericParams. |
| |
| // Note that we intentionally don't forward the generic arguments. |
| |
| // Add all the primary archetypes. |
| // TODO: only the *primary* archetypes. |
| // TODO: not archetypes from outer contexts. |
| for (auto archetype : generics.getAllArchetypes()) { |
| asImpl().addGenericArgument(archetype, args...); |
| } |
| |
| // Add protocol witness tables for those archetypes. |
| for (auto archetype : generics.getAllArchetypes()) { |
| asImpl().beginGenericWitnessTables(archetype, args...); |
| for (auto protocol : archetype->getConformsTo()) { |
| if (Lowering::TypeConverter::protocolRequiresWitnessTable(protocol)) |
| asImpl().addGenericWitnessTable(archetype, protocol, args...); |
| } |
| asImpl().endGenericWitnessTables(archetype, args...); |
| } |
| } |
| |
| template <class... T> |
| void beginGenericWitnessTables(ArchetypeType *type, T &&...args) {} |
| |
| template <class... T> |
| void endGenericWitnessTables(ArchetypeType *type, T &&...args) {} |
| }; |
| |
| } // end namespace irgen |
| } // end namespace swift |
| |
| #endif |