Author: brunoricci Date: Wed Aug 15 09:21:17 2018 New Revision: 339787 URL: http://llvm.org/viewvc/llvm-project?rev=339787&view=rev Log: [AST] Pack the bits of TemplateSpecializationType into Type
Type has enough space for two members of TemplateSpecializationType. Mechanical patch. Reviewed By: erichkeane Differential Revision: https://reviews.llvm.org/D50643 Modified: cfe/trunk/include/clang/AST/Type.h cfe/trunk/lib/AST/Type.cpp Modified: cfe/trunk/include/clang/AST/Type.h URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/AST/Type.h?rev=339787&r1=339786&r2=339787&view=diff ============================================================================== --- cfe/trunk/include/clang/AST/Type.h (original) +++ cfe/trunk/include/clang/AST/Type.h Wed Aug 15 09:21:17 2018 @@ -1606,6 +1606,24 @@ protected: unsigned Keyword : 2; }; + class TemplateSpecializationTypeBitfields { + friend class TemplateSpecializationType; + + unsigned : NumTypeBits; + + /// Whether this template specialization type is a substituted type alias. + unsigned TypeAlias : 1; + + /// The number of template arguments named in this class template + /// specialization, which is expected to be able to hold at least 1024 + /// according to [implimits]. However, as this limit is somewhat easy to + /// hit with template metaprogramming we'd prefer to keep it as large + /// as possible. At the moment it has been left as a non-bitfield since + /// this type safely fits in 64 bits as an unsigned, so there is no reason + /// to introduce the performance impact of a bitfield. + unsigned NumArgs; + }; + union { TypeBitfields TypeBits; ArrayTypeBitfields ArrayTypeBits; @@ -1617,6 +1635,7 @@ protected: ReferenceTypeBitfields ReferenceTypeBits; TypeWithKeywordBitfields TypeWithKeywordBits; VectorTypeBitfields VectorTypeBits; + TemplateSpecializationTypeBitfields TemplateSpecializationTypeBits; static_assert(sizeof(TypeBitfields) <= 8, "TypeBitfields is larger than 8 bytes!"); @@ -1638,6 +1657,9 @@ protected: "TypeWithKeywordBitfields is larger than 8 bytes!"); static_assert(sizeof(VectorTypeBitfields) <= 8, "VectorTypeBitfields is larger than 8 bytes!"); + static_assert(sizeof(TemplateSpecializationTypeBitfields) <= 8, + "TemplateSpecializationTypeBitfields is larger" + " than 8 bytes!"); }; private: @@ -4669,13 +4691,6 @@ class alignas(8) TemplateSpecializationT /// replacement must, recursively, be one of these). TemplateName Template; - /// The number of template arguments named in this class template - /// specialization. - unsigned NumArgs : 31; - - /// Whether this template specialization type is a substituted type alias. - unsigned TypeAlias : 1; - TemplateSpecializationType(TemplateName T, ArrayRef<TemplateArgument> Args, QualType Canon, @@ -4710,7 +4725,7 @@ public: /// typedef A<Ts...> type; // not a type alias /// }; /// \endcode - bool isTypeAlias() const { return TypeAlias; } + bool isTypeAlias() const { return TemplateSpecializationTypeBits.TypeAlias; } /// Get the aliased type, if this is a specialization of a type alias /// template. @@ -4733,14 +4748,16 @@ public: } /// Retrieve the number of template arguments. - unsigned getNumArgs() const { return NumArgs; } + unsigned getNumArgs() const { + return TemplateSpecializationTypeBits.NumArgs; + } /// Retrieve a specific template argument as a type. /// \pre \c isArgType(Arg) const TemplateArgument &getArg(unsigned Idx) const; // in TemplateBase.h ArrayRef<TemplateArgument> template_arguments() const { - return {getArgs(), NumArgs}; + return {getArgs(), getNumArgs()}; } bool isSugared() const { Modified: cfe/trunk/lib/AST/Type.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/Type.cpp?rev=339787&r1=339786&r2=339787&view=diff ============================================================================== --- cfe/trunk/lib/AST/Type.cpp (original) +++ cfe/trunk/lib/AST/Type.cpp Wed Aug 15 09:21:17 2018 @@ -3335,8 +3335,10 @@ TemplateSpecializationType(TemplateName Canon.isNull()? true : Canon->isDependentType(), Canon.isNull()? true : Canon->isInstantiationDependentType(), false, - T.containsUnexpandedParameterPack()), - Template(T), NumArgs(Args.size()), TypeAlias(!AliasedType.isNull()) { + T.containsUnexpandedParameterPack()), Template(T) { + TemplateSpecializationTypeBits.NumArgs = Args.size(); + TemplateSpecializationTypeBits.TypeAlias = !AliasedType.isNull(); + assert(!T.getAsDependentTemplateName() && "Use DependentTemplateSpecializationType for dependent template-name"); assert((T.getKind() == TemplateName::Template || @@ -3365,7 +3367,7 @@ TemplateSpecializationType(TemplateName } // Store the aliased type if this is a type alias template specialization. - if (TypeAlias) { + if (isTypeAlias()) { auto *Begin = reinterpret_cast<TemplateArgument *>(this + 1); *reinterpret_cast<QualType*>(Begin + getNumArgs()) = AliasedType; } _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
