/* * Copyright (C) 1998-2000 Netscape Communications Corporation. * Copyright (C) 2003-6 Apple Computer * Copyright (C) Research In Motion Limited 2010. All rights reserved. * * Other contributors: * Nick Blievers * Jeff Hostetler * Tom Rini * Raffaele Sena * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA * * Alternatively, the contents of this file may be used under the terms * of either the Mozilla Public License Version 1.1, found at * http://www.mozilla.org/MPL/ (the "MPL") or the GNU General Public * License Version 2.0, found at http://www.fsf.org/copyleft/gpl.html * (the "GPL"), in which case the provisions of the MPL or the GPL are * applicable instead of those above. If you wish to allow use of your * version of this file only under the terms of one of those two * licenses (the MPL or the GPL) and not to allow others to use your * version of this file under the LGPL, indicate your decision by * deletingthe provisions above and replace them with the notice and * other provisions required by the MPL or the GPL, as the case may be. * If you do not delete the provisions above, a recipient may use your * version of this file under any of the LGPL, the MPL or the GPL. */ #ifndef Arena_h #define Arena_h // FIXME: We'd always like to use AllocAlignmentInteger for Arena alignment // but there is concern over the memory growth this may cause. #ifdef WTF_USE_ARENA_ALLOC_ALIGNMENT_INTEGER #define ARENA_ALIGN_MASK (sizeof(WTF::AllocAlignmentInteger) - 1) #else #define ARENA_ALIGN_MASK 3 #endif namespace WebCore { typedef uintptr_t uword; struct Arena { Arena* next; // next arena uword base; // aligned base address uword limit; // end of arena (1+last byte) uword avail; // points to next available byte in arena }; struct ArenaPool { Arena first; // first arena in pool list. Arena* current; // current arena. unsigned int arenasize; uword mask; // Mask (power-of-2 - 1) }; void InitArenaPool(ArenaPool*, const char* name, unsigned int size, unsigned int align); void FinishArenaPool(ArenaPool*); void* ArenaAllocate(ArenaPool*, unsigned int numBytes, unsigned int& bytesAllocated); #define ARENA_ALIGN(n) (((uword)(n) + ARENA_ALIGN_MASK) & ~ARENA_ALIGN_MASK) #define INIT_ARENA_POOL(pool, name, size) InitArenaPool(pool, name, size, ARENA_ALIGN_MASK + 1) #define ARENA_ALLOCATE(p, pool, nb, bytesAllocated) \ Arena* _a = (pool)->current; \ unsigned int _nb = ARENA_ALIGN(nb); \ uword _p = _a->avail; \ uword _q = _p + _nb; \ if (_q > _a->limit) \ _p = (uword)ArenaAllocate(pool, _nb, *bytesAllocated); \ else \ _a->avail = _q; \ p = (void*)_p; } #endif