diff options
Diffstat (limited to 'src/google/protobuf/arena.h')
| -rw-r--r-- | src/google/protobuf/arena.h | 895 |
1 files changed, 320 insertions, 575 deletions
diff --git a/src/google/protobuf/arena.h b/src/google/protobuf/arena.h index 05e05ebc..9928c8e6 100644 --- a/src/google/protobuf/arena.h +++ b/src/google/protobuf/arena.h @@ -37,10 +37,7 @@ #ifdef max #undef max // Visual Studio defines this macro #endif -#if __cplusplus >= 201103L -#include <google/protobuf/stubs/type_traits.h> -#endif -#if defined(_MSC_VER) && !_HAS_EXCEPTIONS +#if defined(_MSC_VER) && !defined(_LIBCPP_STD_VER) && !_HAS_EXCEPTIONS // Work around bugs in MSVC <typeinfo> header when _HAS_EXCEPTIONS=0. #include <exception> #include <typeinfo> @@ -51,32 +48,50 @@ using type_info = ::type_info; #include <typeinfo> #endif -#include <google/protobuf/stubs/atomic_sequence_num.h> -#include <google/protobuf/stubs/atomicops.h> -#include <google/protobuf/stubs/common.h> -#include <google/protobuf/stubs/logging.h> -#include <google/protobuf/stubs/mutex.h> -#include <google/protobuf/stubs/type_traits.h> - +#include <google/protobuf/arena_impl.h> +#include <google/protobuf/stubs/port.h> +#include <type_traits> namespace google { namespace protobuf { -class Arena; // defined below -class Message; // message.h +struct ArenaOptions; // defined below + +} // namespace protobuf + +namespace quality_webanswers { + +void TempPrivateWorkAround(::google::protobuf::ArenaOptions* arena_options); + +} // namespace quality_webanswers + +namespace protobuf { + +class Arena; // defined below +class Message; // defined in message.h +class MessageLite; + +namespace arena_metrics { + +void EnableArenaMetrics(::google::protobuf::ArenaOptions* options); + +} // namespace arena_metrics namespace internal { -class ArenaString; // arenastring.h -class LazyField; // lazy_field.h -template<typename Type> -class GenericTypeHandler; // repeated_field.h +struct ArenaStringPtr; // defined in arenastring.h +class LazyField; // defined in lazy_field.h + +template <typename Type> +class GenericTypeHandler; // defined in repeated_field.h // Templated cleanup methods. -template<typename T> void arena_destruct_object(void* object) { +template <typename T> +void arena_destruct_object(void* object) { reinterpret_cast<T*>(object)->~T(); } -template<typename T> void arena_delete_object(void* object) { +template <typename T> +void arena_delete_object(void* object) { delete reinterpret_cast<T*>(object); } inline void arena_free(void* object, size_t size) { @@ -123,6 +138,19 @@ struct ArenaOptions { // calls free. void (*block_dealloc)(void*, size_t); + ArenaOptions() + : start_block_size(kDefaultStartBlockSize), + max_block_size(kDefaultMaxBlockSize), + initial_block(NULL), + initial_block_size(0), + block_alloc(&::operator new), + block_dealloc(&internal::arena_free), + on_arena_init(NULL), + on_arena_reset(NULL), + on_arena_destruction(NULL), + on_arena_allocation(NULL) {} + + private: // Hooks for adding external functionality such as user-specific metrics // collection, specific debugging abilities, etc. // Init hook may return a pointer to a cookie to be stored in the arena. @@ -142,25 +170,17 @@ struct ArenaOptions { // intentionally want to avoid monitoring an allocation. (i.e. internal // allocations for managing the arena) void (*on_arena_allocation)(const std::type_info* allocated_type, - uint64 alloc_size, void* cookie); + uint64 alloc_size, void* cookie); - ArenaOptions() - : start_block_size(kDefaultStartBlockSize), - max_block_size(kDefaultMaxBlockSize), - initial_block(NULL), - initial_block_size(0), - block_alloc(&::operator new), - block_dealloc(&internal::arena_free), - on_arena_init(NULL), - on_arena_reset(NULL), - on_arena_destruction(NULL), - on_arena_allocation(NULL) {} - - private: // Constants define default starting block size and max block size for // arena allocator behavior -- see descriptions above. static const size_t kDefaultStartBlockSize = 256; - static const size_t kDefaultMaxBlockSize = 8192; + static const size_t kDefaultMaxBlockSize = 8192; + + friend void ::google::protobuf::arena_metrics::EnableArenaMetrics(ArenaOptions*); + friend void quality_webanswers::TempPrivateWorkAround(ArenaOptions*); + friend class Arena; + friend class ArenaOptionsTestFriend; }; // Support for non-RTTI environments. (The metrics hooks API uses type @@ -225,21 +245,40 @@ class LIBPROTOBUF_EXPORT Arena { public: // Arena constructor taking custom options. See ArenaOptions below for // descriptions of the options available. - explicit Arena(const ArenaOptions& options) : options_(options) { - Init(); + explicit Arena(const ArenaOptions& options) : impl_(options) { + Init(options); } + // Block overhead. Use this as a guide for how much to over-allocate the + // initial block if you want an allocation of size N to fit inside it. + // + // WARNING: if you allocate multiple objects, it is difficult to guarantee + // that a series of allocations will fit in the initial block, especially if + // Arena changes its alignment guarantees in the future! + static const size_t kBlockOverhead = internal::ArenaImpl::kBlockHeaderSize + + internal::ArenaImpl::kSerialArenaSize; + // Default constructor with sensible default options, tuned for average // use-cases. - Arena() { - Init(); + Arena() : impl_(ArenaOptions()) { Init(ArenaOptions()); } + + ~Arena() { + if (hooks_cookie_) { + CallDestructorHooks(); + } } - // Destructor deletes all owned heap allocated objects, and destructs objects - // that have non-trivial destructors, except for proto2 message objects whose - // destructors can be skipped. Also, frees all blocks except the initial block - // if it was passed in. - ~Arena(); + void Init(const ArenaOptions& options) { + on_arena_allocation_ = options.on_arena_allocation; + on_arena_reset_ = options.on_arena_reset; + on_arena_destruction_ = options.on_arena_destruction; + // Call the initialization hook + if (options.on_arena_init != NULL) { + hooks_cookie_ = options.on_arena_init(this); + } else { + hooks_cookie_ = NULL; + } + } // API to create proto2 message objects on the arena. If the arena passed in // is NULL, then a heap allocated object is returned. Type T must be a message @@ -251,41 +290,16 @@ class LIBPROTOBUF_EXPORT Arena { // // This function also accepts any type T that satisfies the arena message // allocation protocol, documented above. - template <typename T> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - static T* CreateMessage(::google::protobuf::Arena* arena) { - if (arena == NULL) { - return new T; - } else { - return arena->CreateMessageInternal<T>(static_cast<T*>(0)); - } - } - - // One-argument form of CreateMessage. This is useful for constructing objects - // that implement the arena message construction protocol described above but - // take additional constructor arguments. - template <typename T, typename Arg> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - static T* CreateMessage(::google::protobuf::Arena* arena, const Arg& arg) { - if (arena == NULL) { - return new T(NULL, arg); - } else { - return arena->CreateMessageInternal<T>(static_cast<T*>(0), - arg); - } - } - - // Two-argument form of CreateMessage. This is useful for constructing objects - // that implement the arena message construction protocol described above but - // take additional constructor arguments. - template <typename T, typename Arg1, typename Arg2> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - static T* CreateMessage(::google::protobuf::Arena* arena, - const Arg1& arg1, - const Arg2& arg2) { - if (arena == NULL) { - return new T(NULL, arg1, arg2); - } else { - return arena->CreateMessageInternal<T>(static_cast<T*>(0), - arg1, arg2); - } + template <typename T, typename... Args> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE static T* CreateMessage( + Arena* arena, Args&&... args) { + static_assert( + InternalHelper<T>::is_arena_constructable::value, + "CreateMessage can only construct types that are ArenaConstructable"); + // We must delegate to CreateMaybeMessage() and NOT CreateMessageInternal() + // because protobuf generated classes specialize CreateMaybeMessage() and we + // need to use that specialization for code size reasons. + return Arena::CreateMaybeMessage<T>(arena, std::forward<Args>(args)...); } // API to create any objects on the arena. Note that only the object will @@ -303,143 +317,11 @@ class LIBPROTOBUF_EXPORT Arena { // (unless the destructor is trivial). Hence, from T's point of view, it is as // if the object were allocated on the heap (except that the underlying memory // is obtained from the arena). - template <typename T> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - static T* Create(::google::protobuf::Arena* arena) { - if (arena == NULL) { - return new T(); - } else { - return arena->CreateInternal<T>(google::protobuf::internal::has_trivial_destructor<T>::value); - } - } - - // Version of the above with one constructor argument for the created object. - template <typename T, typename Arg> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - static T* Create(::google::protobuf::Arena* arena, const Arg& arg) { - if (arena == NULL) { - return new T(arg); - } else { - return arena->CreateInternal<T>(google::protobuf::internal::has_trivial_destructor<T>::value, - arg); - } - } -#if LANG_CXX11 - template <typename T, typename Arg> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - static T* Create(::google::protobuf::Arena* arena, Arg&& arg) { - if (arena == NULL) { - return new T(std::move(arg)); - } else { - return arena->CreateInternal<T>(google::protobuf::internal::has_trivial_destructor<T>::value, - std::move(arg)); - } - } -#endif - - // Version of the above with two constructor arguments for the created object. - template <typename T, typename Arg1, typename Arg2> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - static T* Create(::google::protobuf::Arena* arena, const Arg1& arg1, const Arg2& arg2) { - if (arena == NULL) { - return new T(arg1, arg2); - } else { - return arena->CreateInternal<T>(google::protobuf::internal::has_trivial_destructor<T>::value, - arg1, arg2); - } - } - - // Version of the above with three constructor arguments for the created - // object. - template <typename T, typename Arg1, typename Arg2, typename Arg3> - GOOGLE_ATTRIBUTE_ALWAYS_INLINE static T* Create(::google::protobuf::Arena* arena, - const Arg1& arg1, const Arg2& arg2, - const Arg3& arg3) { - if (arena == NULL) { - return new T(arg1, arg2, arg3); - } else { - return arena->CreateInternal<T>(google::protobuf::internal::has_trivial_destructor<T>::value, - arg1, arg2, arg3); - } - } - - // Version of the above with four constructor arguments for the created - // object. - template <typename T, typename Arg1, typename Arg2, typename Arg3, - typename Arg4> - GOOGLE_ATTRIBUTE_ALWAYS_INLINE static T* Create(::google::protobuf::Arena* arena, - const Arg1& arg1, const Arg2& arg2, - const Arg3& arg3, const Arg4& arg4) { - if (arena == NULL) { - return new T(arg1, arg2, arg3, arg4); - } else { - return arena->CreateInternal<T>(google::protobuf::internal::has_trivial_destructor<T>::value, - arg1, arg2, arg3, arg4); - } - } - - // Version of the above with five constructor arguments for the created - // object. - template <typename T, typename Arg1, typename Arg2, typename Arg3, - typename Arg4, typename Arg5> - GOOGLE_ATTRIBUTE_ALWAYS_INLINE static T* Create(::google::protobuf::Arena* arena, - const Arg1& arg1, const Arg2& arg2, - const Arg3& arg3, const Arg4& arg4, - const Arg5& arg5) { - if (arena == NULL) { - return new T(arg1, arg2, arg3, arg4, arg5); - } else { - return arena->CreateInternal<T>(google::protobuf::internal::has_trivial_destructor<T>::value, - arg1, arg2, arg3, arg4, arg5); - } - } - - // Version of the above with six constructor arguments for the created - // object. - template <typename T, typename Arg1, typename Arg2, typename Arg3, - typename Arg4, typename Arg5, typename Arg6> - GOOGLE_ATTRIBUTE_ALWAYS_INLINE static T* Create(::google::protobuf::Arena* arena, - const Arg1& arg1, const Arg2& arg2, - const Arg3& arg3, const Arg4& arg4, - const Arg5& arg5, const Arg6& arg6) { - if (arena == NULL) { - return new T(arg1, arg2, arg3, arg4, arg5, arg6); - } else { - return arena->CreateInternal<T>(google::protobuf::internal::has_trivial_destructor<T>::value, - arg1, arg2, arg3, arg4, arg5, arg6); - } - } - - // Version of the above with seven constructor arguments for the created - // object. - template <typename T, typename Arg1, typename Arg2, typename Arg3, - typename Arg4, typename Arg5, typename Arg6, typename Arg7> - GOOGLE_ATTRIBUTE_ALWAYS_INLINE static T* Create(::google::protobuf::Arena* arena, - const Arg1& arg1, const Arg2& arg2, - const Arg3& arg3, const Arg4& arg4, - const Arg5& arg5, const Arg6& arg6, - const Arg7& arg7) { - if (arena == NULL) { - return new T(arg1, arg2, arg3, arg4, arg5, arg6, arg7); - } else { - return arena->CreateInternal<T>(google::protobuf::internal::has_trivial_destructor<T>::value, - arg1, arg2, arg3, arg4, arg5, arg6, arg7); - } - } - - // Version of the above with eight constructor arguments for the created - // object. - template <typename T, typename Arg1, typename Arg2, typename Arg3, - typename Arg4, typename Arg5, typename Arg6, typename Arg7, - typename Arg8> - GOOGLE_ATTRIBUTE_ALWAYS_INLINE static T* Create(::google::protobuf::Arena* arena, - const Arg1& arg1, const Arg2& arg2, - const Arg3& arg3, const Arg4& arg4, - const Arg5& arg5, const Arg6& arg6, - const Arg7& arg7, const Arg8& arg8) { - if (arena == NULL) { - return new T(arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8); - } else { - return arena->CreateInternal<T>( - google::protobuf::internal::has_trivial_destructor<T>::value, - arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8); - } + template <typename T, typename... Args> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE static T* Create(Arena* arena, + Args&&... args) { + return CreateNoMessage<T>(arena, is_arena_constructable<T>(), + std::forward<Args>(args)...); } // Create an array of object type T on the arena *without* invoking the @@ -448,10 +330,14 @@ class LIBPROTOBUF_EXPORT Arena { // To ensure safe uses, this function checks at compile time // (when compiled as C++11) that T is trivially default-constructible and // trivially destructible. - template <typename T> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - static T* CreateArray(::google::protobuf::Arena* arena, size_t num_elements) { - GOOGLE_CHECK_LE(num_elements, - std::numeric_limits<size_t>::max() / sizeof(T)) + template <typename T> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE static T* CreateArray( + Arena* arena, size_t num_elements) { + static_assert(std::is_pod<T>::value, + "CreateArray requires a trivially constructible type"); + static_assert(std::is_trivially_destructible<T>::value, + "CreateArray requires a trivially destructible type"); + GOOGLE_CHECK_LE(num_elements, std::numeric_limits<size_t>::max() / sizeof(T)) << "Requested size is too large to fit into size_t."; if (arena == NULL) { return static_cast<T*>(::operator new[](num_elements * sizeof(T))); @@ -463,30 +349,39 @@ class LIBPROTOBUF_EXPORT Arena { // Returns the total space allocated by the arena, which is the sum of the // sizes of the underlying blocks. This method is relatively fast; a counter // is kept as blocks are allocated. - uint64 SpaceAllocated() const; + uint64 SpaceAllocated() const { return impl_.SpaceAllocated(); } // Returns the total space used by the arena. Similar to SpaceAllocated but // does not include free space and block overhead. The total space returned // may not include space used by other threads executing concurrently with // the call to this method. - GOOGLE_ATTRIBUTE_NOINLINE uint64 SpaceUsed() const; + uint64 SpaceUsed() const { return impl_.SpaceUsed(); } // DEPRECATED. Please use SpaceAllocated() and SpaceUsed(). // // Combines SpaceAllocated and SpaceUsed. Returns a pair of // <space_allocated, space_used>. - GOOGLE_ATTRIBUTE_NOINLINE std::pair<uint64, uint64> SpaceAllocatedAndUsed() const; + PROTOBUF_RUNTIME_DEPRECATED("Please use SpaceAllocated() and SpaceUsed()") + std::pair<uint64, uint64> SpaceAllocatedAndUsed() const { + return std::make_pair(SpaceAllocated(), SpaceUsed()); + } // Frees all storage allocated by this arena after calling destructors // registered with OwnDestructor() and freeing objects registered with Own(). // Any objects allocated on this arena are unusable after this call. It also // returns the total space used by the arena which is the sums of the sizes // of the allocated blocks. This method is not thread-safe. - GOOGLE_ATTRIBUTE_NOINLINE uint64 Reset(); + GOOGLE_PROTOBUF_ATTRIBUTE_NOINLINE uint64 Reset() { + // Call the reset hook + if (on_arena_reset_ != NULL) { + on_arena_reset_(this, hooks_cookie_, impl_.SpaceAllocated()); + } + return impl_.Reset(); + } // Adds |object| to a list of heap-allocated objects to be freed with |delete| // when the arena is destroyed or reset. - template <typename T> GOOGLE_ATTRIBUTE_NOINLINE - void Own(T* object) { - OwnInternal(object, google::protobuf::internal::is_convertible<T*, ::google::protobuf::Message*>()); + template <typename T> + GOOGLE_PROTOBUF_ATTRIBUTE_NOINLINE void Own(T* object) { + OwnInternal(object, std::is_convertible<T*, Message*>()); } // Adds |object| to a list of objects whose destructors will be manually @@ -494,10 +389,10 @@ class LIBPROTOBUF_EXPORT Arena { // that it does not free the underlying memory with |delete|; hence, it is // normally only used for objects that are placement-newed into // arena-allocated memory. - template <typename T> GOOGLE_ATTRIBUTE_NOINLINE - void OwnDestructor(T* object) { + template <typename T> + GOOGLE_PROTOBUF_ATTRIBUTE_NOINLINE void OwnDestructor(T* object) { if (object != NULL) { - AddListNode(object, &internal::arena_destruct_object<T>); + impl_.AddCleanup(object, &internal::arena_destruct_object<T>); } } @@ -505,313 +400,205 @@ class LIBPROTOBUF_EXPORT Arena { // will be manually called when the arena is destroyed or reset. This differs // from OwnDestructor() in that any member function may be specified, not only // the class destructor. - GOOGLE_ATTRIBUTE_NOINLINE void OwnCustomDestructor(void* object, - void (*destruct)(void*)) { - AddListNode(object, destruct); + GOOGLE_PROTOBUF_ATTRIBUTE_NOINLINE void OwnCustomDestructor( + void* object, void (*destruct)(void*)) { + impl_.AddCleanup(object, destruct); } // Retrieves the arena associated with |value| if |value| is an arena-capable // message, or NULL otherwise. This differs from value->GetArena() in that the // latter is a virtual call, while this method is a templated call that // resolves at compile-time. - template<typename T> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - static ::google::protobuf::Arena* GetArena(const T* value) { - return GetArenaInternal(value, static_cast<T*>(0)); + template <typename T> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE static Arena* GetArena( + const T* value) { + return GetArenaInternal(value, is_arena_constructable<T>()); } - private: - struct InternalIsArenaConstructableHelper { - template<typename U> + template <typename T> + class InternalHelper { + template <typename U> + static char DestructorSkippable(const typename U::DestructorSkippable_*); + template <typename U> + static double DestructorSkippable(...); + + typedef std::integral_constant< + bool, sizeof(DestructorSkippable<T>(static_cast<const T*>(0))) == + sizeof(char) || + std::is_trivially_destructible<T>::value> + is_destructor_skippable; + + template <typename U> static char ArenaConstructable( const typename U::InternalArenaConstructable_*); - template<typename U> + template <typename U> static double ArenaConstructable(...); + + typedef std::integral_constant<bool, sizeof(ArenaConstructable<T>( + static_cast<const T*>(0))) == + sizeof(char)> + is_arena_constructable; + + template <typename... Args> + static T* Construct(void* ptr, Args&&... args) { + return new (ptr) T(std::forward<Args>(args)...); + } + + static Arena* GetArena(const T* p) { return p->GetArenaNoVirtual(); } + + friend class Arena; }; - public: - // Helper typetrait that indicates support for arenas in a type T at compile + // Helper typetraits that indicates support for arenas in a type T at compile // time. This is public only to allow construction of higher-level templated - // utilities. is_arena_constructable<T>::value is true if the message type T - // has arena support enabled, and false otherwise. + // utilities. + // + // is_arena_constructable<T>::value is true if the message type T has arena + // support enabled, and false otherwise. + // + // is_destructor_skippable<T>::value is true if the message type T has told + // the arena that it is safe to skip the destructor, and false otherwise. // // This is inside Arena because only Arena has the friend relationships // necessary to see the underlying generated code traits. template <typename T> - struct is_arena_constructable - : public google::protobuf::internal::integral_constant< - bool, sizeof(InternalIsArenaConstructableHelper::ArenaConstructable< - const T>(static_cast<const T*>(0))) == sizeof(char)> { + struct is_arena_constructable : InternalHelper<T>::is_arena_constructable {}; + template <typename T> + struct is_destructor_skippable : InternalHelper<T>::is_destructor_skippable { }; private: - // Blocks are variable length malloc-ed objects. The following structure - // describes the common header for all blocks. - struct Block { - void* owner; // &ThreadCache of thread that owns this block, or - // &this->owner if not yet owned by a thread. - Block* next; // Next block in arena (may have different owner) - // ((char*) &block) + pos is next available byte. It is always - // aligned at a multiple of 8 bytes. - size_t pos; - size_t size; // total size of the block. - GOOGLE_ATTRIBUTE_ALWAYS_INLINE size_t avail() const { return size - pos; } - // data follows - }; - - template<typename Type> friend class ::google::protobuf::internal::GenericTypeHandler; - friend class MockArena; // For unit-testing. - friend class internal::ArenaString; // For AllocateAligned. - friend class internal::LazyField; // For CreateMaybeMessage. - - struct ThreadCache { - // The ThreadCache is considered valid as long as this matches the - // lifecycle_id of the arena being used. - int64 last_lifecycle_id_seen; - Block* last_block_used_; - }; - - static const size_t kHeaderSize = sizeof(Block); - static google::protobuf::internal::SequenceNumber lifecycle_id_generator_; -#if defined(GOOGLE_PROTOBUF_NO_THREADLOCAL) - // Android ndk does not support GOOGLE_THREAD_LOCAL keyword so we use a custom thread - // local storage class we implemented. - // iOS also does not support the GOOGLE_THREAD_LOCAL keyword. - static ThreadCache& thread_cache(); -#elif defined(PROTOBUF_USE_DLLS) - // Thread local variables cannot be exposed through DLL interface but we can - // wrap them in static functions. - static ThreadCache& thread_cache(); -#else - static GOOGLE_THREAD_LOCAL ThreadCache thread_cache_; - static ThreadCache& thread_cache() { return thread_cache_; } -#endif + template <typename T, typename... Args> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE static T* CreateMessageInternal( + Arena* arena, Args&&... args) { + static_assert( + InternalHelper<T>::is_arena_constructable::value, + "CreateMessage can only construct types that are ArenaConstructable"); + if (arena == NULL) { + return new T(nullptr, std::forward<Args>(args)...); + } else { + return arena->DoCreateMessage<T>(std::forward<Args>(args)...); + } + } - // SFINAE for skipping addition to delete list for a message type when created - // with CreateMessage. This is mainly to skip proto2/proto1 message objects - // with cc_enable_arenas=true from being part of the delete list. Also, note, - // compiler will optimize out the branch in CreateInternal<T>. - template<typename T> - static inline bool SkipDeleteList(typename T::DestructorSkippable_*) { - return true; + // This specialization for no arguments is necessary, because its behavior is + // slightly different. When the arena pointer is nullptr, it calls T() + // instead of T(nullptr). + template <typename T> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE static T* CreateMessageInternal( + Arena* arena) { + static_assert( + InternalHelper<T>::is_arena_constructable::value, + "CreateMessage can only construct types that are ArenaConstructable"); + if (arena == NULL) { + return new T(); + } else { + return arena->DoCreateMessage<T>(); + } } - // For message objects that don't have the DestructorSkippable_ trait, we - // always add to the delete list. - template<typename T> - static inline bool SkipDeleteList(...) { - return google::protobuf::internal::has_trivial_destructor<T>::value; + template <typename T, typename... Args> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE static T* CreateInternal( + Arena* arena, Args&&... args) { + if (arena == NULL) { + return new T(std::forward<Args>(args)...); + } else { + return arena->DoCreate<T>(std::is_trivially_destructible<T>::value, + std::forward<Args>(args)...); + } } - private: - struct InternalIsDestructorSkippableHelper { - template<typename U> - static char DestructorSkippable( - const typename U::DestructorSkippable_*); - template<typename U> - static double DestructorSkippable(...); - }; + void CallDestructorHooks(); + void OnArenaAllocation(const std::type_info* allocated_type, size_t n) const; + inline void AllocHook(const std::type_info* allocated_type, size_t n) const { + if (GOOGLE_PREDICT_FALSE(hooks_cookie_ != NULL)) { + OnArenaAllocation(allocated_type, n); + } + } - public: - // Helper typetrait that indicates whether the desctructor of type T should be - // called when arena is destroyed at compile time. This is only to allow - // construction of higher-level templated utilities. - // is_destructor_skippable<T>::value is true if the destructor of the message - // type T should not be called when arena is destroyed or false otherwise. - // This is inside Arena because only Arena has the friend relationships - // necessary to see the underlying generated code traits. - template<typename T> - struct is_destructor_skippable - : public google::protobuf::internal::integral_constant< - bool, - sizeof(InternalIsDestructorSkippableHelper::DestructorSkippable< - const T>(static_cast<const T*>(0))) == sizeof(char) || - google::protobuf::internal::has_trivial_destructor<T>::value> {}; + // Allocate and also optionally call on_arena_allocation callback with the + // allocated type info when the hooks are in place in ArenaOptions and + // the cookie is not null. + template <typename T> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE void* AllocateInternal( + bool skip_explicit_ownership) { + const size_t n = internal::AlignUpTo8(sizeof(T)); + AllocHook(RTTI_TYPE_ID(T), n); + // Monitor allocation if needed. + if (skip_explicit_ownership) { + return impl_.AllocateAligned(n); + } else { + return impl_.AllocateAlignedAndAddCleanup( + n, &internal::arena_destruct_object<T>); + } + } - private: // CreateMessage<T> requires that T supports arenas, but this private method // works whether or not T supports arenas. These are not exposed to user code // as it can cause confusing API usages, and end up having double free in // user code. These are used only internally from LazyField and Repeated // fields, since they are designed to work in all mode combinations. - template<typename Msg> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - static Msg* CreateMaybeMessage( - Arena* arena, typename Msg::InternalArenaConstructable_*) { - return CreateMessage<Msg>(arena); - } - - template<typename T> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - static T* CreateMaybeMessage(Arena* arena, ...) { - return Create<T>(arena); - } - - // Just allocate the required size for the given type assuming the - // type has a trivial constructor. - template<typename T> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - T* CreateInternalRawArray(size_t num_elements) { - GOOGLE_CHECK_LE(num_elements, - std::numeric_limits<size_t>::max() / sizeof(T)) - << "Requested size is too large to fit into size_t."; - return static_cast<T*>( - AllocateAligned(RTTI_TYPE_ID(T), sizeof(T) * num_elements)); + template <typename Msg, typename... Args> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE static Msg* DoCreateMaybeMessage( + Arena* arena, std::true_type, Args&&... args) { + return CreateMessageInternal<Msg>(arena, std::forward<Args>(args)...); } - template <typename T> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - T* CreateInternal(bool skip_explicit_ownership) { - T* t = new (AllocateAligned(RTTI_TYPE_ID(T), sizeof(T))) T(); - if (!skip_explicit_ownership) { - AddListNode(t, &internal::arena_destruct_object<T>); - } - return t; + template <typename T, typename... Args> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE static T* DoCreateMaybeMessage( + Arena* arena, std::false_type, Args&&... args) { + return CreateInternal<T>(arena, std::forward<Args>(args)...); } - template <typename T, typename Arg> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - T* CreateInternal(bool skip_explicit_ownership, const Arg& arg) { - T* t = new (AllocateAligned(RTTI_TYPE_ID(T), sizeof(T))) T(arg); - if (!skip_explicit_ownership) { - AddListNode(t, &internal::arena_destruct_object<T>); - } - return t; + template <typename T, typename... Args> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE static T* CreateMaybeMessage( + Arena* arena, Args&&... args) { + return DoCreateMaybeMessage<T>(arena, is_arena_constructable<T>(), + std::forward<Args>(args)...); } -#if LANG_CXX11 - template <typename T, typename Arg> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - T* CreateInternal(bool skip_explicit_ownership, Arg&& arg) { - T* t = new (AllocateAligned(RTTI_TYPE_ID(T), sizeof(T))) T( - std::move(arg)); - if (!skip_explicit_ownership) { - AddListNode(t, &internal::arena_destruct_object<T>); - } - return t; + template <typename T, typename... Args> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE static T* CreateNoMessage( + Arena* arena, std::true_type, Args&&... args) { + // User is constructing with Create() despite the fact that T supports arena + // construction. In this case we have to delegate to CreateInternal(), and + // we can't use any CreateMaybeMessage() specialization that may be defined. + return CreateInternal<T>(arena, std::forward<Args>(args)...); } -#endif - template <typename T, typename Arg1, typename Arg2> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - T* CreateInternal( - bool skip_explicit_ownership, const Arg1& arg1, const Arg2& arg2) { - T* t = new (AllocateAligned(RTTI_TYPE_ID(T), sizeof(T))) T(arg1, arg2); - if (!skip_explicit_ownership) { - AddListNode(t, &internal::arena_destruct_object<T>); - } - return t; - } - - template <typename T, typename Arg1, typename Arg2, typename Arg3> - GOOGLE_ATTRIBUTE_ALWAYS_INLINE T* CreateInternal(bool skip_explicit_ownership, - const Arg1& arg1, - const Arg2& arg2, - const Arg3& arg3) { - T* t = new (AllocateAligned(RTTI_TYPE_ID(T), sizeof(T))) - T(arg1, arg2, arg3); - if (!skip_explicit_ownership) { - AddListNode(t, &internal::arena_destruct_object<T>); - } - return t; - } - - template <typename T, typename Arg1, typename Arg2, typename Arg3, - typename Arg4> - GOOGLE_ATTRIBUTE_ALWAYS_INLINE T* CreateInternal(bool skip_explicit_ownership, - const Arg1& arg1, - const Arg2& arg2, - const Arg3& arg3, - const Arg4& arg4) { - T* t = new (AllocateAligned(RTTI_TYPE_ID(T), sizeof(T))) - T(arg1, arg2, arg3, arg4); - if (!skip_explicit_ownership) { - AddListNode(t, &internal::arena_destruct_object<T>); - } - return t; - } - - template <typename T, typename Arg1, typename Arg2, typename Arg3, - typename Arg4, typename Arg5> - GOOGLE_ATTRIBUTE_ALWAYS_INLINE T* CreateInternal(bool skip_explicit_ownership, - const Arg1& arg1, - const Arg2& arg2, - const Arg3& arg3, - const Arg4& arg4, - const Arg5& arg5) { - T* t = new (AllocateAligned(RTTI_TYPE_ID(T), sizeof(T))) - T(arg1, arg2, arg3, arg4, arg5); - if (!skip_explicit_ownership) { - AddListNode(t, &internal::arena_destruct_object<T>); - } - return t; - } - - template <typename T, typename Arg1, typename Arg2, typename Arg3, - typename Arg4, typename Arg5, typename Arg6> - GOOGLE_ATTRIBUTE_ALWAYS_INLINE T* CreateInternal(bool skip_explicit_ownership, - const Arg1& arg1, - const Arg2& arg2, - const Arg3& arg3, - const Arg4& arg4, - const Arg5& arg5, - const Arg6& arg6) { - T* t = new (AllocateAligned(RTTI_TYPE_ID(T), sizeof(T))) - T(arg1, arg2, arg3, arg4, arg5, arg6); - if (!skip_explicit_ownership) { - AddListNode(t, &internal::arena_destruct_object<T>); - } - return t; - } - - template <typename T, typename Arg1, typename Arg2, typename Arg3, - typename Arg4, typename Arg5, typename Arg6, typename Arg7> - GOOGLE_ATTRIBUTE_ALWAYS_INLINE T* CreateInternal(bool skip_explicit_ownership, - const Arg1& arg1, - const Arg2& arg2, - const Arg3& arg3, - const Arg4& arg4, - const Arg5& arg5, - const Arg6& arg6, - const Arg7& arg7) { - T* t = new (AllocateAligned(RTTI_TYPE_ID(T), sizeof(T))) - T(arg1, arg2, arg3, arg4, arg5, arg6, arg7); - if (!skip_explicit_ownership) { - AddListNode(t, &internal::arena_destruct_object<T>); - } - return t; - } - - template <typename T, typename Arg1, typename Arg2, typename Arg3, - typename Arg4, typename Arg5, typename Arg6, typename Arg7, - typename Arg8> - GOOGLE_ATTRIBUTE_ALWAYS_INLINE T* CreateInternal(bool skip_explicit_ownership, - const Arg1& arg1, - const Arg2& arg2, - const Arg3& arg3, - const Arg4& arg4, - const Arg5& arg5, - const Arg6& arg6, - const Arg7& arg7, - const Arg8& arg8) { - T* t = new (AllocateAligned(RTTI_TYPE_ID(T), sizeof(T))) - T(arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8); - if (!skip_explicit_ownership) { - AddListNode(t, &internal::arena_destruct_object<T>); - } - return t; + template <typename T, typename... Args> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE static T* CreateNoMessage( + Arena* arena, std::false_type, Args&&... args) { + // User is constructing with Create() and the type does not support arena + // construction. In this case we can delegate to CreateMaybeMessage() and + // use any specialization that may be available for that. + return CreateMaybeMessage<T>(arena, std::forward<Args>(args)...); } - template <typename T> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - T* CreateMessageInternal(typename T::InternalArenaConstructable_*) { - return CreateInternal<T, Arena*>(SkipDeleteList<T>(static_cast<T*>(0)), - this); + // Just allocate the required size for the given type assuming the + // type has a trivial constructor. + template <typename T> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE T* CreateInternalRawArray( + size_t num_elements) { + GOOGLE_CHECK_LE(num_elements, std::numeric_limits<size_t>::max() / sizeof(T)) + << "Requested size is too large to fit into size_t."; + const size_t n = internal::AlignUpTo8(sizeof(T) * num_elements); + // Monitor allocation if needed. + AllocHook(RTTI_TYPE_ID(T), n); + return static_cast<T*>(impl_.AllocateAligned(n)); } - template <typename T, typename Arg> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - T* CreateMessageInternal(typename T::InternalArenaConstructable_*, - const Arg& arg) { - return CreateInternal<T, Arena*>(SkipDeleteList<T>(static_cast<T*>(0)), - this, arg); + template <typename T, typename... Args> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE T* DoCreate( + bool skip_explicit_ownership, Args&&... args) { + return new (AllocateInternal<T>(skip_explicit_ownership)) + T(std::forward<Args>(args)...); } - - template <typename T, typename Arg1, typename Arg2> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - T* CreateMessageInternal(typename T::InternalArenaConstructable_*, - const Arg1& arg1, const Arg2& arg2) { - return CreateInternal<T, Arena*>(SkipDeleteList<T>(static_cast<T*>(0)), - this, arg1, arg2); + template <typename T, typename... Args> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE T* DoCreateMessage(Args&&... args) { + return InternalHelper<T>::Construct( + AllocateInternal<T>(InternalHelper<T>::is_destructor_skippable::value), + this, std::forward<Args>(args)...); } // CreateInArenaStorage is used to implement map field. Without it, @@ -821,27 +608,28 @@ class LIBPROTOBUF_EXPORT Arena { static void CreateInArenaStorage(T* ptr, Arena* arena) { CreateInArenaStorageInternal(ptr, arena, typename is_arena_constructable<T>::type()); - RegisterDestructorInternal(ptr, arena, - typename is_destructor_skippable<T>::type()); + RegisterDestructorInternal( + ptr, arena, + typename InternalHelper<T>::is_destructor_skippable::type()); } template <typename T> - static void CreateInArenaStorageInternal( - T* ptr, Arena* arena, google::protobuf::internal::true_type) { - new (ptr) T(arena); + static void CreateInArenaStorageInternal(T* ptr, Arena* arena, + std::true_type) { + InternalHelper<T>::Construct(ptr, arena); } template <typename T> - static void CreateInArenaStorageInternal( - T* ptr, Arena* arena, google::protobuf::internal::false_type) { + static void CreateInArenaStorageInternal(T* ptr, Arena* /* arena */, + std::false_type) { new (ptr) T(); } template <typename T> - static void RegisterDestructorInternal( - T* ptr, Arena* arena, google::protobuf::internal::true_type) {} + static void RegisterDestructorInternal(T* /* ptr */, Arena* /* arena */, + std::true_type) {} template <typename T> - static void RegisterDestructorInternal( - T* ptr, Arena* arena, google::protobuf::internal::false_type) { + static void RegisterDestructorInternal(T* ptr, Arena* arena, + std::false_type) { arena->OwnDestructor(ptr); } @@ -850,103 +638,60 @@ class LIBPROTOBUF_EXPORT Arena { // is a subtype of ::google::protobuf::Message and 'false_type' otherwise. Collapsing // all template instantiations to one for generic Message reduces code size, // using the virtual destructor instead. - template<typename T> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - void OwnInternal(T* object, google::protobuf::internal::true_type) { + template <typename T> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE void OwnInternal(T* object, + std::true_type) { if (object != NULL) { - AddListNode(object, &internal::arena_delete_object< ::google::protobuf::Message >); + impl_.AddCleanup(object, &internal::arena_delete_object<Message>); } } - template<typename T> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - void OwnInternal(T* object, google::protobuf::internal::false_type) { + template <typename T> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE void OwnInternal(T* object, + std::false_type) { if (object != NULL) { - AddListNode(object, &internal::arena_delete_object<T>); + impl_.AddCleanup(object, &internal::arena_delete_object<T>); } } // Implementation for GetArena(). Only message objects with // InternalArenaConstructable_ tags can be associated with an arena, and such // objects must implement a GetArenaNoVirtual() method. - template<typename T> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - static ::google::protobuf::Arena* GetArenaInternal( - const T* value, typename T::InternalArenaConstructable_*) { - return value->GetArenaNoVirtual(); + template <typename T> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE static Arena* GetArenaInternal( + const T* value, std::true_type) { + return InternalHelper<T>::GetArena(value); } - template<typename T> GOOGLE_ATTRIBUTE_ALWAYS_INLINE - static ::google::protobuf::Arena* GetArenaInternal(const T* value, ...) { + template <typename T> + GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE static Arena* GetArenaInternal( + const T* /* value */, std::false_type) { return NULL; } - // Allocate and also optionally call on_arena_allocation callback with the - // allocated type info when the hooks are in place in ArenaOptions and - // the cookie is not null. - void* AllocateAligned(const std::type_info* allocated, size_t n); - - // Allocate an internal allocation, avoiding optional typed monitoring. - GOOGLE_ATTRIBUTE_ALWAYS_INLINE void* AllocateAligned(size_t n) { - return AllocateAligned(NULL, n); - } - - void Init(); - - // Free all blocks and return the total space used which is the sums of sizes - // of the all the allocated blocks. - uint64 FreeBlocks(); - - // Add object pointer and cleanup function pointer to the list. - // TODO(rohananil, cfallin): We could pass in a sub-arena into this method - // to avoid polluting blocks of this arena with list nodes. This would help in - // mixed mode (where many protobufs have cc_enable_arenas=false), and is an - // alternative to a chunked linked-list, but with extra overhead of *next. - void AddListNode(void* elem, void (*cleanup)(void*)); - // Delete or Destruct all objects owned by the arena. - void CleanupList(); - uint64 ResetInternal(); - - inline void SetThreadCacheBlock(Block* block) { - thread_cache().last_block_used_ = block; - thread_cache().last_lifecycle_id_seen = lifecycle_id_; + // For friends of arena. + void* AllocateAligned(size_t n) { + AllocHook(NULL, n); + return impl_.AllocateAligned(internal::AlignUpTo8(n)); } - int64 lifecycle_id_; // Unique for each arena. Changes on Reset(). - - google::protobuf::internal::AtomicWord blocks_; // Head of linked list of all allocated blocks - google::protobuf::internal::AtomicWord hint_; // Fast thread-local block access - uint64 space_allocated_; // Sum of sizes of all allocated blocks. + internal::ArenaImpl impl_; - // Node contains the ptr of the object to be cleaned up and the associated - // cleanup function ptr. - struct Node { - void* elem; // Pointer to the object to be cleaned up. - void (*cleanup)(void*); // Function pointer to the destructor or deleter. - Node* next; // Next node in the list. - }; - - google::protobuf::internal::AtomicWord cleanup_list_; // Head of a linked list of nodes containing object - // ptrs and cleanup methods. - - bool owns_first_block_; // Indicates that arena owns the first block - mutable Mutex blocks_lock_; - - void AddBlock(Block* b); - // Access must be synchronized, either by blocks_lock_ or by being called from - // Init()/Reset(). - void AddBlockInternal(Block* b); - void* SlowAlloc(size_t n); - Block* FindBlock(void* me); - Block* NewBlock(void* me, Block* my_last_block, size_t n, - size_t start_block_size, size_t max_block_size); - static void* AllocFromBlock(Block* b, size_t n); - template <typename Key, typename T> - friend class Map; + void (*on_arena_allocation_)(const std::type_info* allocated_type, + uint64 alloc_size, void* cookie); + void (*on_arena_reset_)(Arena* arena, void* cookie, uint64 space_used); + void (*on_arena_destruction_)(Arena* arena, void* cookie, uint64 space_used); // The arena may save a cookie it receives from the external on_init hook // and then use it when calling the on_reset and on_destruction hooks. void* hooks_cookie_; - ArenaOptions options_; - - GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(Arena); + template <typename Type> + friend class internal::GenericTypeHandler; + friend struct internal::ArenaStringPtr; // For AllocateAligned. + friend class internal::LazyField; // For CreateMaybeMessage. + friend class MessageLite; + template <typename Key, typename T> + friend class Map; }; // Defined above for supporting environments without RTTI. |