/js/lib/Socket.IO-node/support/expresso/deps/jscoverage/js/jsarena.h
C++ Header | 318 lines | 185 code | 47 blank | 86 comment | 18 complexity | 91c647bcc2878fbbba1fcfda277f2c8e MD5 | raw file
1/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- 2 * 3 * ***** BEGIN LICENSE BLOCK ***** 4 * Version: MPL 1.1/GPL 2.0/LGPL 2.1 5 * 6 * The contents of this file are subject to the Mozilla Public License Version 7 * 1.1 (the "License"); you may not use this file except in compliance with 8 * the License. You may obtain a copy of the License at 9 * http://www.mozilla.org/MPL/ 10 * 11 * Software distributed under the License is distributed on an "AS IS" basis, 12 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License 13 * for the specific language governing rights and limitations under the 14 * License. 15 * 16 * The Original Code is Mozilla Communicator client code, released 17 * March 31, 1998. 18 * 19 * The Initial Developer of the Original Code is 20 * Netscape Communications Corporation. 21 * Portions created by the Initial Developer are Copyright (C) 1998 22 * the Initial Developer. All Rights Reserved. 23 * 24 * Contributor(s): 25 * 26 * Alternatively, the contents of this file may be used under the terms of 27 * either of the GNU General Public License Version 2 or later (the "GPL"), 28 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), 29 * in which case the provisions of the GPL or the LGPL are applicable instead 30 * of those above. If you wish to allow use of your version of this file only 31 * under the terms of either the GPL or the LGPL, and not to allow others to 32 * use your version of this file under the terms of the MPL, indicate your 33 * decision by deleting the provisions above and replace them with the notice 34 * and other provisions required by the GPL or the LGPL. If you do not delete 35 * the provisions above, a recipient may use your version of this file under 36 * the terms of any one of the MPL, the GPL or the LGPL. 37 * 38 * ***** END LICENSE BLOCK ***** */ 39 40#ifndef jsarena_h___ 41#define jsarena_h___ 42/* 43 * Lifetime-based fast allocation, inspired by much prior art, including 44 * "Fast Allocation and Deallocation of Memory Based on Object Lifetimes" 45 * David R. Hanson, Software -- Practice and Experience, Vol. 20(1). 46 * 47 * Also supports LIFO allocation (JS_ARENA_MARK/JS_ARENA_RELEASE). 48 */ 49#include <stdlib.h> 50#include "jstypes.h" 51#include "jscompat.h" 52 53JS_BEGIN_EXTERN_C 54 55typedef struct JSArena JSArena; 56typedef struct JSArenaPool JSArenaPool; 57 58struct JSArena { 59 JSArena *next; /* next arena for this lifetime */ 60 jsuword base; /* aligned base address, follows this header */ 61 jsuword limit; /* one beyond last byte in arena */ 62 jsuword avail; /* points to next available byte */ 63}; 64 65#ifdef JS_ARENAMETER 66typedef struct JSArenaStats JSArenaStats; 67 68struct JSArenaStats { 69 JSArenaStats *next; /* next in arenaStats list */ 70 char *name; /* name for debugging */ 71 uint32 narenas; /* number of arenas in pool */ 72 uint32 nallocs; /* number of JS_ARENA_ALLOCATE() calls */ 73 uint32 nmallocs; /* number of malloc() calls */ 74 uint32 ndeallocs; /* number of lifetime deallocations */ 75 uint32 ngrows; /* number of JS_ARENA_GROW() calls */ 76 uint32 ninplace; /* number of in-place growths */ 77 uint32 nreallocs; /* number of arena grow extending reallocs */ 78 uint32 nreleases; /* number of JS_ARENA_RELEASE() calls */ 79 uint32 nfastrels; /* number of "fast path" releases */ 80 size_t nbytes; /* total bytes allocated */ 81 size_t maxalloc; /* maximum allocation size in bytes */ 82 double variance; /* size variance accumulator */ 83}; 84#endif 85 86struct JSArenaPool { 87 JSArena first; /* first arena in pool list */ 88 JSArena *current; /* arena from which to allocate space */ 89 size_t arenasize; /* net exact size of a new arena */ 90 jsuword mask; /* alignment mask (power-of-2 - 1) */ 91 size_t *quotap; /* pointer to the quota on pool allocation 92 size or null if pool is unlimited */ 93#ifdef JS_ARENAMETER 94 JSArenaStats stats; 95#endif 96}; 97 98#ifdef JS_ARENAMETER 99#define JS_INIT_NAMED_ARENA_POOL(pool, name, size, align, quotap) \ 100 JS_InitArenaPool(pool, name, size, align, quotap) 101#else 102#define JS_INIT_NAMED_ARENA_POOL(pool, name, size, align, quotap) \ 103 JS_InitArenaPool(pool, size, align, quotap) 104#endif 105 106/* 107 * If the including .c file uses only one power-of-2 alignment, it may define 108 * JS_ARENA_CONST_ALIGN_MASK to the alignment mask and save a few instructions 109 * per ALLOCATE and GROW. 110 */ 111#ifdef JS_ARENA_CONST_ALIGN_MASK 112#define JS_ARENA_ALIGN(pool, n) (((jsuword)(n) + JS_ARENA_CONST_ALIGN_MASK) \ 113 & ~(jsuword)JS_ARENA_CONST_ALIGN_MASK) 114 115#define JS_INIT_ARENA_POOL(pool, name, size, quotap) \ 116 JS_INIT_NAMED_ARENA_POOL(pool, name, size, JS_ARENA_CONST_ALIGN_MASK + 1, \ 117 quotap) 118 119#else 120#define JS_ARENA_ALIGN(pool, n) (((jsuword)(n) + (pool)->mask) & ~(pool)->mask) 121 122#define JS_INIT_ARENA_POOL(pool, name, size, align, quotap) \ 123 JS_INIT_NAMED_ARENA_POOL(pool, name, size, align, quotap) 124 125#endif 126 127#define JS_ARENA_ALLOCATE(p, pool, nb) \ 128 JS_ARENA_ALLOCATE_CAST(p, void *, pool, nb) 129 130#define JS_ARENA_ALLOCATE_TYPE(p, type, pool) \ 131 JS_ARENA_ALLOCATE_COMMON(p, type *, pool, sizeof(type), 0) 132 133#define JS_ARENA_ALLOCATE_CAST(p, type, pool, nb) \ 134 JS_ARENA_ALLOCATE_COMMON(p, type, pool, nb, _nb > _a->limit) 135 136/* 137 * NB: In JS_ARENA_ALLOCATE_CAST and JS_ARENA_GROW_CAST, always subtract _nb 138 * from a->limit rather than adding _nb to _p, to avoid overflowing a 32-bit 139 * address space (possible when running a 32-bit program on a 64-bit system 140 * where the kernel maps the heap up against the top of the 32-bit address 141 * space). 142 * 143 * Thanks to Juergen Kreileder <jk@blackdown.de>, who brought this up in 144 * https://bugzilla.mozilla.org/show_bug.cgi?id=279273. 145 */ 146#define JS_ARENA_ALLOCATE_COMMON(p, type, pool, nb, guard) \ 147 JS_BEGIN_MACRO \ 148 JSArena *_a = (pool)->current; \ 149 size_t _nb = JS_ARENA_ALIGN(pool, nb); \ 150 jsuword _p = _a->avail; \ 151 if ((guard) || _p > _a->limit - _nb) \ 152 _p = (jsuword)JS_ArenaAllocate(pool, _nb); \ 153 else \ 154 _a->avail = _p + _nb; \ 155 p = (type) _p; \ 156 JS_ArenaCountAllocation(pool, nb); \ 157 JS_END_MACRO 158 159#define JS_ARENA_GROW(p, pool, size, incr) \ 160 JS_ARENA_GROW_CAST(p, void *, pool, size, incr) 161 162#define JS_ARENA_GROW_CAST(p, type, pool, size, incr) \ 163 JS_BEGIN_MACRO \ 164 JSArena *_a = (pool)->current; \ 165 if (_a->avail == (jsuword)(p) + JS_ARENA_ALIGN(pool, size)) { \ 166 size_t _nb = (size) + (incr); \ 167 _nb = JS_ARENA_ALIGN(pool, _nb); \ 168 if (_a->limit >= _nb && (jsuword)(p) <= _a->limit - _nb) { \ 169 _a->avail = (jsuword)(p) + _nb; \ 170 JS_ArenaCountInplaceGrowth(pool, size, incr); \ 171 } else if ((jsuword)(p) == _a->base) { \ 172 p = (type) JS_ArenaRealloc(pool, p, size, incr); \ 173 } else { \ 174 p = (type) JS_ArenaGrow(pool, p, size, incr); \ 175 } \ 176 } else { \ 177 p = (type) JS_ArenaGrow(pool, p, size, incr); \ 178 } \ 179 JS_ArenaCountGrowth(pool, size, incr); \ 180 JS_END_MACRO 181 182#define JS_ARENA_MARK(pool) ((void *) (pool)->current->avail) 183#define JS_UPTRDIFF(p,q) ((jsuword)(p) - (jsuword)(q)) 184 185/* 186 * Check if the mark is inside arena's allocated area. 187 */ 188#define JS_ARENA_MARK_MATCH(a, mark) \ 189 (JS_UPTRDIFF(mark, (a)->base) <= JS_UPTRDIFF((a)->avail, (a)->base)) 190 191#ifdef DEBUG 192#define JS_FREE_PATTERN 0xDA 193#define JS_CLEAR_UNUSED(a) (JS_ASSERT((a)->avail <= (a)->limit), \ 194 memset((void*)(a)->avail, JS_FREE_PATTERN, \ 195 (a)->limit - (a)->avail)) 196#define JS_CLEAR_ARENA(a) memset((void*)(a), JS_FREE_PATTERN, \ 197 (a)->limit - (jsuword)(a)) 198#else 199#define JS_CLEAR_UNUSED(a) /* nothing */ 200#define JS_CLEAR_ARENA(a) /* nothing */ 201#endif 202 203#define JS_ARENA_RELEASE(pool, mark) \ 204 JS_BEGIN_MACRO \ 205 char *_m = (char *)(mark); \ 206 JSArena *_a = (pool)->current; \ 207 if (_a != &(pool)->first && JS_ARENA_MARK_MATCH(_a, _m)) { \ 208 _a->avail = (jsuword)JS_ARENA_ALIGN(pool, _m); \ 209 JS_ASSERT(_a->avail <= _a->limit); \ 210 JS_CLEAR_UNUSED(_a); \ 211 JS_ArenaCountRetract(pool, _m); \ 212 } else { \ 213 JS_ArenaRelease(pool, _m); \ 214 } \ 215 JS_ArenaCountRelease(pool, _m); \ 216 JS_END_MACRO 217 218#ifdef JS_ARENAMETER 219#define JS_COUNT_ARENA(pool,op) ((pool)->stats.narenas op) 220#else 221#define JS_COUNT_ARENA(pool,op) 222#endif 223 224#define JS_ARENA_DESTROY(pool, a, pnext) \ 225 JS_BEGIN_MACRO \ 226 JS_COUNT_ARENA(pool,--); \ 227 if ((pool)->current == (a)) (pool)->current = &(pool)->first; \ 228 *(pnext) = (a)->next; \ 229 JS_CLEAR_ARENA(a); \ 230 free(a); \ 231 (a) = NULL; \ 232 JS_END_MACRO 233 234/* 235 * Initialize an arena pool with a minimum size per arena of size bytes. 236 * Always call JS_SET_ARENA_METER_NAME before calling this or use 237 * JS_INIT_ARENA_POOL macro to provide a name for for debugging and metering. 238 */ 239extern JS_PUBLIC_API(void) 240JS_INIT_NAMED_ARENA_POOL(JSArenaPool *pool, const char *name, size_t size, 241 size_t align, size_t *quotap); 242 243/* 244 * Free the arenas in pool. The user may continue to allocate from pool 245 * after calling this function. There is no need to call JS_InitArenaPool() 246 * again unless JS_FinishArenaPool(pool) has been called. 247 */ 248extern JS_PUBLIC_API(void) 249JS_FreeArenaPool(JSArenaPool *pool); 250 251/* 252 * Free the arenas in pool and finish using it altogether. 253 */ 254extern JS_PUBLIC_API(void) 255JS_FinishArenaPool(JSArenaPool *pool); 256 257/* 258 * Deprecated do-nothing function. 259 */ 260extern JS_PUBLIC_API(void) 261JS_ArenaFinish(void); 262 263/* 264 * Deprecated do-nothing function. 265 */ 266extern JS_PUBLIC_API(void) 267JS_ArenaShutDown(void); 268 269/* 270 * Friend functions used by the JS_ARENA_*() macros. 271 */ 272extern JS_PUBLIC_API(void *) 273JS_ArenaAllocate(JSArenaPool *pool, size_t nb); 274 275extern JS_PUBLIC_API(void *) 276JS_ArenaRealloc(JSArenaPool *pool, void *p, size_t size, size_t incr); 277 278extern JS_PUBLIC_API(void *) 279JS_ArenaGrow(JSArenaPool *pool, void *p, size_t size, size_t incr); 280 281extern JS_PUBLIC_API(void) 282JS_ArenaRelease(JSArenaPool *pool, char *mark); 283 284#ifdef JS_ARENAMETER 285 286#include <stdio.h> 287 288extern JS_PUBLIC_API(void) 289JS_ArenaCountAllocation(JSArenaPool *pool, size_t nb); 290 291extern JS_PUBLIC_API(void) 292JS_ArenaCountInplaceGrowth(JSArenaPool *pool, size_t size, size_t incr); 293 294extern JS_PUBLIC_API(void) 295JS_ArenaCountGrowth(JSArenaPool *pool, size_t size, size_t incr); 296 297extern JS_PUBLIC_API(void) 298JS_ArenaCountRelease(JSArenaPool *pool, char *mark); 299 300extern JS_PUBLIC_API(void) 301JS_ArenaCountRetract(JSArenaPool *pool, char *mark); 302 303extern JS_PUBLIC_API(void) 304JS_DumpArenaStats(FILE *fp); 305 306#else /* !JS_ARENAMETER */ 307 308#define JS_ArenaCountAllocation(ap, nb) /* nothing */ 309#define JS_ArenaCountInplaceGrowth(ap, size, incr) /* nothing */ 310#define JS_ArenaCountGrowth(ap, size, incr) /* nothing */ 311#define JS_ArenaCountRelease(ap, mark) /* nothing */ 312#define JS_ArenaCountRetract(ap, mark) /* nothing */ 313 314#endif /* !JS_ARENAMETER */ 315 316JS_END_EXTERN_C 317 318#endif /* jsarena_h___ */