// Copyright 2020 the V8 project authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef V8_HEAP_CPPGC_FREE_LIST_H_ #define V8_HEAP_CPPGC_FREE_LIST_H_ #include <array> #include "include/cppgc/heap-statistics.h" #include "src/base/macros.h" #include "src/heap/cppgc/globals.h" #include "src/heap/cppgc/heap-object-header.h" namespace cppgc { namespace internal { class V8_EXPORT_PRIVATE FreeList { public: struct Block { void* address; size_t size; }; FreeList(); FreeList(const FreeList&) = delete; FreeList& operator=(const FreeList&) = delete; FreeList(FreeList&& freelist) V8_NOEXCEPT; FreeList& operator=(FreeList&& freelist) V8_NOEXCEPT; // Allocates entries which are at least of the provided size. Block Allocate(size_t); // Adds block to the freelist. The minimal block size is two words. void Add(Block); // Append other freelist into this. void Append(FreeList&&); void Clear(); size_t Size() const; bool IsEmpty() const; void CollectStatistics(HeapStatistics::FreeListStatistics&); bool ContainsForTesting(Block) const; private: class Entry; bool IsConsistent(size_t) const; // All |Entry|s in the nth list have size >= 2^n. std::array<Entry*, kPageSizeLog2> free_list_heads_; std::array<Entry*, kPageSizeLog2> free_list_tails_; size_t biggest_free_list_index_ = 0; }; } // namespace internal } // namespace cppgc #endif // V8_HEAP_CPPGC_FREE_LIST_H_