khtml/misc/arena.h

   1 /*
   2  * Copyright (C) 1998-2000 Netscape Communications Corporation.
   3  *
   4  * Other contributors:
   5  *   Nick Blievers <nickb@adacel.com.au>
   6  *   Jeff Hostetler <jeff@nerdone.com>
   7  *   Tom Rini <trini@kernel.crashing.org>
   8  *   Raffaele Sena <raff@netwinder.org>
   9  *
  10  * This library is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU Lesser General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2.1 of the License, or (at your option) any later version.
  14  *
  15  * This library is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public
  21  * License along with this library; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  23  *
  24  * Alternatively, the contents of this file may be used under the terms
  25  * of either the Mozilla Public License Version 1.1, found at
  26  * http://www.mozilla.org/MPL/ (the "MPL") or the GNU General Public
  27  * License Version 2.0, found at http://www.fsf.org/copyleft/gpl.html
  28  * (the "GPL"), in which case the provisions of the MPL or the GPL are
  29  * applicable instead of those above.  If you wish to allow use of your
  30  * version of this file only under the terms of one of those two
  31  * licenses (the MPL or the GPL) and not to allow others to use your
  32  * version of this file under the LGPL, indicate your decision by
  33  * deletingthe provisions above and replace them with the notice and
  34  * other provisions required by the MPL or the GPL, as the case may be.
  35  * If you do not delete the provisions above, a recipient may use your
  36  * version of this file under any of the LGPL, the MPL or the GPL.
  37  */
  38
  39 #ifndef ARENA_H
  40 #define ARENA_H
  41
  42 #include <config-khtml.h>
  43
  44 // VG annotations for arenas disabled since still buggy
  45 #if 0 && defined(HAVE_VALGRIND_MEMCHECK_H) && !defined(NDEBUG)
  46
  47 #include <valgrind/memcheck.h>
  48 #define VALGRIND_SUPPORT
  49
  50 #else
  51
  52 #define VALGRIND_CREATE_MEMPOOL(base, redZone, zeroed)
  53 #define VALGRIND_DESTROY_MEMPOOL(base)
  54 #define VALGRIND_MEMPOOL_ALLOC(base, addr, size)
  55 #define VALGRIND_MEMPOOL_FREE(base, addr)
  56
  57 #endif
  58
  59
  60 #define ARENA_ALIGN_MASK 3
  61
  62 typedef unsigned long uword;
  63
  64 namespace khtml {
  65
  66 struct Arena {
  67     Arena* next;        // next arena
  68     uword base;         // aligned base address
  69     uword limit;        // end of arena (1+last byte)
  70     uword avail;        // points to next available byte in arena
  71 };
  72
  73 struct ArenaPool {
  74     Arena first;        // first arena in pool list.
  75     Arena* current;     // current arena.
  76     unsigned int arenasize;
  77     unsigned int largealloc; // threshold for fractional allocation strategy
  78     unsigned int cumul; // total bytes in pool.
  79     uword mask;         // Mask (power-of-2 - 1)
  80 };
  81
  82 void InitArenaPool(ArenaPool *pool, const char *name,
  83                    unsigned int size, unsigned int align);
  84 void FinishArenaPool(ArenaPool *pool);
  85 void FreeArenaPool(ArenaPool *pool);
  86 void* ArenaAllocate(ArenaPool *pool, unsigned int nb);
  87 void ArenaFinish(void);
  88
  89 #define ARENA_ALIGN(pool, n) (((uword)(n) + ARENA_ALIGN_MASK) & ~ARENA_ALIGN_MASK)
  90 #define INIT_ARENA_POOL(pool, name, size) \
  91         InitArenaPool(pool, name, size, ARENA_ALIGN_MASK + 1)
  92
  93 #define ARENA_ALLOCATE(p, pool, nb) \
  94         Arena *_a = (pool)->current; \
  95         unsigned int _nb = ARENA_ALIGN(pool, nb); \
  96         uword _p = _a->avail; \
  97         uword _q = _p + _nb; \
  98         if (_q > _a->limit) \
  99             _p = (uword)ArenaAllocate(pool, _nb); \
 100         else { \
 101             VALGRIND_MEMPOOL_ALLOC(_a->base, _p, _nb); \
 102             _a->avail = _q; \
 103         } \
 104         p = (void *)_p;
 105
 106
 107 #define ARENA_MARK(pool) ((void *) (pool)->current->avail)
 108 #define UPTRDIFF(p,q) ((uword)(p) - (uword)(q))
 109
 110 #ifdef DEBUG
 111 #define FREE_PATTERN 0xDA
 112 #define CLEAR_UNUSED(a) (assert((a)->avail <= (a)->limit), \
 113                            memset((void*)(a)->avail, FREE_PATTERN, \
 114                             (a)->limit - (a)->avail))
 115 #define CLEAR_ARENA(a)  memset((void*)(a), FREE_PATTERN, \
 116                             (a)->limit - (uword)(a))
 117 #else
 118 #define CLEAR_UNUSED(a)
 119 #define CLEAR_ARENA(a)
 120 #endif
 121
 122
 123 } // namespace
 124
 125 #endif