Mercurial > hg > graal-compiler
view src/share/vm/memory/metachunk.hpp @ 9463:902a974d55c8
Merge.
author | Doug Simon <doug.simon@oracle.com> |
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date | Tue, 30 Apr 2013 23:24:25 +0200 |
parents | e51c9860cf66 |
children | c23dbf0e8ab7 |
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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_METACHUNK_HPP #define SHARE_VM_MEMORY_METACHUNK_HPP // Metachunk - Quantum of allocation from a Virtualspace // Metachunks are reused (when freed are put on a global freelist) and // have no permanent association to a SpaceManager. // +--------------+ <- end // | | --+ ---+ // | | | free | // | | | | // | | | | capacity // | | | | // | | <- top --+ | // | | ---+ | // | | | used | // | | | | // | | | | // +--------------+ <- bottom ---+ ---+ class Metachunk VALUE_OBJ_CLASS_SPEC { // link to support lists of chunks Metachunk* _next; Metachunk* _prev; MetaWord* _bottom; MetaWord* _end; MetaWord* _top; size_t _word_size; // Used in a guarantee() so included in the Product builds // even through it is only for debugging. bool _is_free; // Metachunks are allocated out of a MetadataVirtualSpace and // and use some of its space to describe itself (plus alignment // considerations). Metadata is allocated in the rest of the chunk. // This size is the overhead of maintaining the Metachunk within // the space. static size_t _overhead; void set_bottom(MetaWord* v) { _bottom = v; } void set_end(MetaWord* v) { _end = v; } void set_top(MetaWord* v) { _top = v; } void set_word_size(size_t v) { _word_size = v; } public: #ifdef ASSERT Metachunk() : _bottom(NULL), _end(NULL), _top(NULL), _is_free(false), _next(NULL), _prev(NULL) {} #else Metachunk() : _bottom(NULL), _end(NULL), _top(NULL), _next(NULL), _prev(NULL) {} #endif // Used to add a Metachunk to a list of Metachunks void set_next(Metachunk* v) { _next = v; assert(v != this, "Boom");} void set_prev(Metachunk* v) { _prev = v; assert(v != this, "Boom");} MetaWord* allocate(size_t word_size); static Metachunk* initialize(MetaWord* ptr, size_t word_size); // Accessors Metachunk* next() const { return _next; } Metachunk* prev() const { return _prev; } MetaWord* bottom() const { return _bottom; } MetaWord* end() const { return _end; } MetaWord* top() const { return _top; } size_t word_size() const { return _word_size; } size_t size() const volatile { return _word_size; } void set_size(size_t v) { _word_size = v; } bool is_free() { return _is_free; } void set_is_free(bool v) { _is_free = v; } static size_t overhead() { return _overhead; } void clear_next() { set_next(NULL); } void link_prev(Metachunk* ptr) { set_prev(ptr); } uintptr_t* end() { return ((uintptr_t*) this) + size(); } bool cantCoalesce() const { return false; } void link_next(Metachunk* ptr) { set_next(ptr); } void link_after(Metachunk* ptr){ link_next(ptr); if (ptr != NULL) ptr->link_prev(this); } // Reset top to bottom so chunk can be reused. void reset_empty() { _top = (_bottom + _overhead); _next = NULL; _prev = NULL; } bool is_empty() { return _top == (_bottom + _overhead); } // used (has been allocated) // free (available for future allocations) // capacity (total size of chunk) size_t used_word_size() const; size_t free_word_size() const; size_t capacity_word_size()const; // Debug support #ifdef ASSERT void* prev_addr() const { return (void*)&_prev; } void* next_addr() const { return (void*)&_next; } void* size_addr() const { return (void*)&_word_size; } #endif bool verify_chunk_in_free_list(Metachunk* tc) const { return true; } bool verify_par_locked() { return true; } void assert_is_mangled() const {/* Don't check "\*/} NOT_PRODUCT(void mangle();) void print_on(outputStream* st) const; void verify(); }; #endif // SHARE_VM_MEMORY_METACHUNK_HPP