| /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ |
| /* ***** BEGIN LICENSE BLOCK ***** |
| * Version: MPL 1.1/GPL 2.0/LGPL 2.1 |
| * |
| * The contents of this file are subject to the Mozilla Public License Version |
| * 1.1 (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * http://www.mozilla.org/MPL/ |
| * |
| * Software distributed under the License is distributed on an "AS IS" basis, |
| * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License |
| * for the specific language governing rights and limitations under the |
| * License. |
| * |
| * The Original Code is the Netscape Portable Runtime (NSPR). |
| * |
| * The Initial Developer of the Original Code is Netscape |
| * Communications Corporation. Portions created by Netscape are |
| * Copyright (C) 1998-2000 Netscape Communications Corporation. All |
| * Rights Reserved. |
| * |
| * Contributor(s): |
| * |
| * Alternatively, the contents of this file may be used under the terms of |
| * either the GNU General Public License Version 2 or later (the "GPL"), or |
| * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), |
| * in which case the provisions of the GPL or the LGPL are applicable instead |
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| * decision by deleting the provisions above and replace them with the notice |
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| * the provisions above, a recipient may use your version of this file under |
| * the terms of any one of the MPL, the GPL or the LGPL. |
| * |
| * ***** END LICENSE BLOCK ***** |
| */ |
| |
| #ifndef plarena_h___ |
| #define plarena_h___ |
| /* |
| * Lifetime-based fast allocation, inspired by much prior art, including |
| * "Fast Allocation and Deallocation of Memory Based on Object Lifetimes" |
| * David R. Hanson, Software -- Practice and Experience, Vol. 20(1). |
| * |
| * Also supports LIFO allocation (PL_ARENA_MARK/PL_ARENA_RELEASE). |
| */ |
| #include "prtypes.h" |
| #include "plarenas.h" |
| |
| PR_BEGIN_EXTERN_C |
| |
| typedef struct PLArena PLArena; |
| |
| struct PLArena { |
| PLArena *next; /* next arena for this lifetime */ |
| PRUword base; /* aligned base address, follows this header */ |
| PRUword limit; /* one beyond last byte in arena */ |
| PRUword avail; /* points to next available byte */ |
| }; |
| |
| #ifdef PL_ARENAMETER |
| typedef struct PLArenaStats PLArenaStats; |
| |
| struct PLArenaStats { |
| PLArenaStats *next; /* next in arenaStats list */ |
| char *name; /* name for debugging */ |
| PRUint32 narenas; /* number of arenas in pool */ |
| PRUint32 nallocs; /* number of PL_ARENA_ALLOCATE() calls */ |
| PRUint32 nreclaims; /* number of reclaims from freeArenas */ |
| PRUint32 nmallocs; /* number of malloc() calls */ |
| PRUint32 ndeallocs; /* number of lifetime deallocations */ |
| PRUint32 ngrows; /* number of PL_ARENA_GROW() calls */ |
| PRUint32 ninplace; /* number of in-place growths */ |
| PRUint32 nreleases; /* number of PL_ARENA_RELEASE() calls */ |
| PRUint32 nfastrels; /* number of "fast path" releases */ |
| PRUint32 nbytes; /* total bytes allocated */ |
| PRUint32 maxalloc; /* maximum allocation size in bytes */ |
| PRFloat64 variance; /* size variance accumulator */ |
| }; |
| #endif |
| |
| struct PLArenaPool { |
| PLArena first; /* first arena in pool list */ |
| PLArena *current; /* arena from which to allocate space */ |
| PRUint32 arenasize; /* net exact size of a new arena */ |
| PRUword mask; /* alignment mask (power-of-2 - 1) */ |
| #ifdef PL_ARENAMETER |
| PLArenaStats stats; |
| #endif |
| }; |
| |
| /* |
| * If the including .c file uses only one power-of-2 alignment, it may define |
| * PL_ARENA_CONST_ALIGN_MASK to the alignment mask and save a few instructions |
| * per ALLOCATE and GROW. |
| */ |
| #ifdef PL_ARENA_CONST_ALIGN_MASK |
| #define PL_ARENA_ALIGN(pool, n) (((PRUword)(n) + PL_ARENA_CONST_ALIGN_MASK) \ |
| & ~PL_ARENA_CONST_ALIGN_MASK) |
| |
| #define PL_INIT_ARENA_POOL(pool, name, size) \ |
| PL_InitArenaPool(pool, name, size, PL_ARENA_CONST_ALIGN_MASK + 1) |
| #else |
| #define PL_ARENA_ALIGN(pool, n) (((PRUword)(n) + (pool)->mask) & ~(pool)->mask) |
| #endif |
| |
| #define PL_ARENA_ALLOCATE(p, pool, nb) \ |
| PR_BEGIN_MACRO \ |
| PLArena *_a = (pool)->current; \ |
| PRUint32 _nb = PL_ARENA_ALIGN(pool, nb); \ |
| PRUword _p = _a->avail; \ |
| PRUword _q = _p + _nb; \ |
| if (_q > _a->limit) \ |
| _p = (PRUword)PL_ArenaAllocate(pool, _nb); \ |
| else \ |
| _a->avail = _q; \ |
| p = (void *)_p; \ |
| PL_ArenaCountAllocation(pool, nb); \ |
| PR_END_MACRO |
| |
| #define PL_ARENA_GROW(p, pool, size, incr) \ |
| PR_BEGIN_MACRO \ |
| PLArena *_a = (pool)->current; \ |
| PRUint32 _incr = PL_ARENA_ALIGN(pool, incr); \ |
| PRUword _p = _a->avail; \ |
| PRUword _q = _p + _incr; \ |
| if (_p == (PRUword)(p) + PL_ARENA_ALIGN(pool, size) && \ |
| _q <= _a->limit) { \ |
| _a->avail = _q; \ |
| PL_ArenaCountInplaceGrowth(pool, size, incr); \ |
| } else { \ |
| p = PL_ArenaGrow(pool, p, size, incr); \ |
| } \ |
| PL_ArenaCountGrowth(pool, size, incr); \ |
| PR_END_MACRO |
| |
| #define PL_ARENA_MARK(pool) ((void *) (pool)->current->avail) |
| #define PR_UPTRDIFF(p,q) ((PRUword)(p) - (PRUword)(q)) |
| |
| #define PL_CLEAR_UNUSED_PATTERN(a, pattern) \ |
| (PR_ASSERT((a)->avail <= (a)->limit), \ |
| memset((void*)(a)->avail, (pattern), (a)->limit - (a)->avail)) |
| #ifdef DEBUG |
| #define PL_FREE_PATTERN 0xDA |
| #define PL_CLEAR_UNUSED(a) PL_CLEAR_UNUSED_PATTERN((a), PL_FREE_PATTERN) |
| #define PL_CLEAR_ARENA(a) memset((void*)(a), PL_FREE_PATTERN, \ |
| (a)->limit - (PRUword)(a)) |
| #else |
| #define PL_CLEAR_UNUSED(a) |
| #define PL_CLEAR_ARENA(a) |
| #endif |
| |
| #define PL_ARENA_RELEASE(pool, mark) \ |
| PR_BEGIN_MACRO \ |
| char *_m = (char *)(mark); \ |
| PLArena *_a = (pool)->current; \ |
| if (PR_UPTRDIFF(_m, _a->base) <= PR_UPTRDIFF(_a->avail, _a->base)) { \ |
| _a->avail = (PRUword)PL_ARENA_ALIGN(pool, _m); \ |
| PL_CLEAR_UNUSED(_a); \ |
| PL_ArenaCountRetract(pool, _m); \ |
| } else { \ |
| PL_ArenaRelease(pool, _m); \ |
| } \ |
| PL_ArenaCountRelease(pool, _m); \ |
| PR_END_MACRO |
| |
| #ifdef PL_ARENAMETER |
| #define PL_COUNT_ARENA(pool,op) ((pool)->stats.narenas op) |
| #else |
| #define PL_COUNT_ARENA(pool,op) |
| #endif |
| |
| #define PL_ARENA_DESTROY(pool, a, pnext) \ |
| PR_BEGIN_MACRO \ |
| PL_COUNT_ARENA(pool,--); \ |
| if ((pool)->current == (a)) (pool)->current = &(pool)->first; \ |
| *(pnext) = (a)->next; \ |
| PL_CLEAR_ARENA(a); \ |
| free(a); \ |
| (a) = 0; \ |
| PR_END_MACRO |
| |
| #ifdef PL_ARENAMETER |
| |
| #include <stdio.h> |
| |
| PR_EXTERN(void) PL_ArenaCountAllocation(PLArenaPool *pool, PRUint32 nb); |
| |
| PR_EXTERN(void) PL_ArenaCountInplaceGrowth( |
| PLArenaPool *pool, PRUint32 size, PRUint32 incr); |
| |
| PR_EXTERN(void) PL_ArenaCountGrowth( |
| PLArenaPool *pool, PRUint32 size, PRUint32 incr); |
| |
| PR_EXTERN(void) PL_ArenaCountRelease(PLArenaPool *pool, char *mark); |
| |
| PR_EXTERN(void) PL_ArenaCountRetract(PLArenaPool *pool, char *mark); |
| |
| PR_EXTERN(void) PL_DumpArenaStats(FILE *fp); |
| |
| #else /* !PL_ARENAMETER */ |
| |
| #define PL_ArenaCountAllocation(ap, nb) /* nothing */ |
| #define PL_ArenaCountInplaceGrowth(ap, size, incr) /* nothing */ |
| #define PL_ArenaCountGrowth(ap, size, incr) /* nothing */ |
| #define PL_ArenaCountRelease(ap, mark) /* nothing */ |
| #define PL_ArenaCountRetract(ap, mark) /* nothing */ |
| |
| #endif /* !PL_ARENAMETER */ |
| |
| PR_END_EXTERN_C |
| |
| #endif /* plarena_h___ */ |
