Mercurial > hg > truffle
view src/share/vm/memory/metablock.hpp @ 7263:6ed187f3134b
added unit test for array copy intrinsification
author | Doug Simon <doug.simon@oracle.com> |
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date | Tue, 18 Dec 2012 15:22:01 +0100 |
parents | 685df3c6f84b |
children | 335b388c4b28 |
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/* * Copyright (c) 2012, 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_VM_MEMORY_METABLOCK_HPP #define SHARE_VM_MEMORY_METABLOCK_HPP // Metablock are the unit of allocation from a Chunk. It is initialized // with the size of the requested allocation. That size is overwritten // once the allocation returns. // // A Metablock may be reused by its SpaceManager but are never moved between // SpaceManagers. There is no explicit link to the Metachunk // from which it was allocated. Metablock may be deallocated and // put on a freelist but the space is never freed, rather // the Metachunk it is a part of will be deallocated when it's // associated class loader is collected. class Metablock VALUE_OBJ_CLASS_SPEC { friend class VMStructs; private: // Used to align the allocation (see below). union block_t { void* _data[3]; struct header_t { size_t _word_size; Metablock* _next; Metablock* _prev; } _header; } _block; static size_t _min_block_byte_size; static size_t _overhead; typedef union block_t Block; typedef struct header_t Header; const Block* block() const { return &_block; } const Block::header_t* header() const { return &(block()->_header); } public: static Metablock* initialize(MetaWord* p, size_t word_size); // This places the body of the block at a 2 word boundary // because every block starts on a 2 word boundary. Work out // how to make the body on a 2 word boundary if the block // starts on a arbitrary boundary. JJJ size_t word_size() const { return header()->_word_size; } void set_word_size(size_t v) { _block._header._word_size = v; } size_t size() const volatile { return _block._header._word_size; } void set_size(size_t v) { _block._header._word_size = v; } Metablock* next() const { return header()->_next; } void set_next(Metablock* v) { _block._header._next = v; } Metablock* prev() const { return header()->_prev; } void set_prev(Metablock* v) { _block._header._prev = v; } static size_t min_block_byte_size() { return _min_block_byte_size; } static size_t overhead() { return _overhead; } bool is_free() { return header()->_word_size != 0; } void clear_next() { set_next(NULL); } void link_prev(Metablock* ptr) { set_prev(ptr); } uintptr_t* end() { return ((uintptr_t*) this) + size(); } bool cantCoalesce() const { return false; } void link_next(Metablock* ptr) { set_next(ptr); } void link_after(Metablock* ptr){ link_next(ptr); if (ptr != NULL) ptr->link_prev(this); } // Should not be needed in a free list of Metablocks void markNotFree() { ShouldNotReachHere(); } // Debug support #ifdef ASSERT void* prev_addr() const { return (void*)&_block._header._prev; } void* next_addr() const { return (void*)&_block._header._next; } void* size_addr() const { return (void*)&_block._header._word_size; } #endif bool verify_chunk_in_free_list(Metablock* tc) const { return true; } bool verify_par_locked() { return true; } void assert_is_mangled() const {/* Don't check "\*/} }; #endif // SHARE_VM_MEMORY_METABLOCK_HPP