/* * Copyright (c) 2018, 2019, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #ifndef SHARE_GC_SHARED_MEMALLOCATOR_HPP #define SHARE_GC_SHARED_MEMALLOCATOR_HPP #include "gc/shared/collectedHeap.hpp" #include "memory/memRegion.hpp" #include "oops/oopsHierarchy.hpp" #include "utilities/exceptions.hpp" #include "utilities/macros.hpp" // These fascilities are used for allocating, and initializing newly allocated objects. class MemAllocator: StackObj { protected: class Allocation; CollectedHeap* const _heap; Thread* const _thread; Klass* const _klass; const size_t _word_size; private: // Allocate from the current thread's TLAB, with broken-out slow path. HeapWord* allocate_inside_tlab(Allocation& allocation) const; HeapWord* allocate_inside_tlab_slow(Allocation& allocation) const; HeapWord* allocate_outside_tlab(Allocation& allocation) const; protected: MemAllocator(Klass* klass, size_t word_size, Thread* thread) : _heap(Universe::heap()), _thread(thread), _klass(klass), _word_size(word_size) { } // This function clears the memory of the object void mem_clear(HeapWord* mem) const; // This finish constructing an oop by installing the mark word and the Klass* pointer // last. At the point when the Klass pointer is initialized, this is a constructed object // that must be parseable as an oop by concurrent collectors. inline void finish_mark(HeapWord* mem) const; oop finish(HeapWord* mem) const; // Encode any extra metadata properties for arrays oop finish_with_properties(HeapWord* mem, ArrayStorageProperties storage_props) const; // Raw memory allocation. This may or may not use TLAB allocations to satisfy the // allocation. A GC implementation may override this function to satisfy the allocation // in any way. But the default is to try a TLAB allocation, and otherwise perform // mem_allocate. virtual HeapWord* mem_allocate(Allocation& allocation) const; virtual MemRegion obj_memory_range(oop obj) const { return MemRegion((HeapWord*)obj, _word_size); } public: oop allocate() const; virtual oop initialize(HeapWord* mem) const = 0; }; class ObjAllocator: public MemAllocator { public: ObjAllocator(Klass* klass, size_t word_size, Thread* thread = Thread::current()) : MemAllocator(klass, word_size, thread) {} virtual oop initialize(HeapWord* mem) const; }; class ObjArrayAllocator: public MemAllocator { const int _length; const bool _do_zero; protected: virtual MemRegion obj_memory_range(oop obj) const; public: ObjArrayAllocator(Klass* klass, size_t word_size, int length, bool do_zero, Thread* thread = Thread::current()) : MemAllocator(klass, word_size, thread), _length(length), _do_zero(do_zero) {} virtual oop initialize(HeapWord* mem) const; }; class ClassAllocator: public MemAllocator { public: ClassAllocator(Klass* klass, size_t word_size, Thread* thread = Thread::current()) : MemAllocator(klass, word_size, thread) {} virtual oop initialize(HeapWord* mem) const; }; #endif // SHARE_GC_SHARED_MEMALLOCATOR_HPP