libraries/source/spidermonkey/include-win32-release/nspr/plarena.h

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef plarena_h___
   7 #define plarena_h___
   8 /*
   9  * Lifetime-based fast allocation, inspired by much prior art, including
  10  * "Fast Allocation and Deallocation of Memory Based on Object Lifetimes"
  11  * David R. Hanson, Software -- Practice and Experience, Vol. 20(1).
  12  *
  13  * Also supports LIFO allocation (PL_ARENA_MARK/PL_ARENA_RELEASE).
  14  */
  15 #include "prtypes.h"
  16
  17 PR_BEGIN_EXTERN_C
  18
  19 typedef struct PLArena          PLArena;
  20
  21 struct PLArena {
  22     PLArena     *next;          /* next arena for this lifetime */
  23     PRUword     base;           /* aligned base address, follows this header */
  24     PRUword     limit;          /* one beyond last byte in arena */
  25     PRUword     avail;          /* points to next available byte */
  26 };
  27
  28 #ifdef PL_ARENAMETER
  29 typedef struct PLArenaStats PLArenaStats;
  30
  31 struct PLArenaStats {
  32     PLArenaStats  *next;        /* next in arenaStats list */
  33     char          *name;        /* name for debugging */
  34     PRUint32      narenas;      /* number of arenas in pool */
  35     PRUint32      nallocs;      /* number of PL_ARENA_ALLOCATE() calls */
  36     PRUint32      nreclaims;    /* number of reclaims from freeArenas */
  37     PRUint32      nmallocs;     /* number of malloc() calls */
  38     PRUint32      ndeallocs;    /* number of lifetime deallocations */
  39     PRUint32      ngrows;       /* number of PL_ARENA_GROW() calls */
  40     PRUint32      ninplace;     /* number of in-place growths */
  41     PRUint32      nreleases;    /* number of PL_ARENA_RELEASE() calls */
  42     PRUint32      nfastrels;    /* number of "fast path" releases */
  43     PRUint32      nbytes;       /* total bytes allocated */
  44     PRUint32      maxalloc;     /* maximum allocation size in bytes */
  45     PRFloat64     variance;     /* size variance accumulator */
  46 };
  47 #endif
  48
  49 typedef struct PLArenaPool      PLArenaPool;
  50
  51 struct PLArenaPool {
  52     PLArena     first;          /* first arena in pool list */
  53     PLArena     *current;       /* arena from which to allocate space */
  54     PRUint32    arenasize;      /* net exact size of a new arena */
  55     PRUword     mask;           /* alignment mask (power-of-2 - 1) */
  56 #ifdef PL_ARENAMETER
  57     PLArenaStats stats;
  58 #endif
  59 };
  60
  61 /*
  62  * WARNING: The PL_MAKE_MEM_ macros are for internal use by NSPR. Do NOT use
  63  * them in your code.
  64  *
  65  * NOTE: Valgrind support to be added.
  66  *
  67  * The PL_MAKE_MEM_ macros are modeled after the MOZ_MAKE_MEM_ macros in
  68  * Mozilla's mfbt/MemoryChecking.h. Only AddressSanitizer is supported now.
  69  *
  70  * Provides a common interface to the ASan (AddressSanitizer) and Valgrind
  71  * functions used to mark memory in certain ways. In detail, the following
  72  * three macros are provided:
  73  *
  74  *   PL_MAKE_MEM_NOACCESS  - Mark memory as unsafe to access (e.g. freed)
  75  *   PL_MAKE_MEM_UNDEFINED - Mark memory as accessible, with content undefined
  76  *   PL_MAKE_MEM_DEFINED - Mark memory as accessible, with content defined
  77  *
  78  * With Valgrind in use, these directly map to the three respective Valgrind
  79  * macros. With ASan in use, the NOACCESS macro maps to poisoning the memory,
  80  * while the UNDEFINED/DEFINED macros unpoison memory.
  81  *
  82  * With no memory checker available, all macros expand to the empty statement.
  83  */
  84
  85 /* WARNING: PL_SANITIZE_ADDRESS is for internal use by this header. Do NOT
  86  * define or test this macro in your code.
  87  */
  88 #if defined(__has_feature)
  89 #if __has_feature(address_sanitizer)
  90 #define PL_SANITIZE_ADDRESS 1
  91 #endif
  92 #elif defined(__SANITIZE_ADDRESS__)
  93 #define PL_SANITIZE_ADDRESS 1
  94 #endif
  95
  96 #if defined(PL_SANITIZE_ADDRESS)
  97
  98 #if defined(_MSC_VER)
  99 /* We can't use dllimport due to DLL linkage mismatch with
 100  * sanitizer/asan_interface.h.
 101  */
 102 #define PL_ASAN_VISIBILITY(type_) type_
 103 #else
 104 #define PL_ASAN_VISIBILITY(type_) PR_IMPORT(type_)
 105 #endif
 106
 107 /* These definitions are usually provided through the
 108  * sanitizer/asan_interface.h header installed by ASan.
 109  * See https://github.com/google/sanitizers/wiki/AddressSanitizerManualPoisoning
 110  */
 111
 112 PL_ASAN_VISIBILITY(void) __asan_poison_memory_region(
 113     void const volatile *addr, size_t size);
 114 PL_ASAN_VISIBILITY(void) __asan_unpoison_memory_region(
 115     void const volatile *addr, size_t size);
 116
 117 #define PL_MAKE_MEM_NOACCESS(addr, size) \
 118     __asan_poison_memory_region((addr), (size))
 119
 120 #define PL_MAKE_MEM_UNDEFINED(addr, size) \
 121     __asan_unpoison_memory_region((addr), (size))
 122
 123 #define PL_MAKE_MEM_DEFINED(addr, size) \
 124     __asan_unpoison_memory_region((addr), (size))
 125
 126 #else
 127
 128 #define PL_MAKE_MEM_NOACCESS(addr, size)
 129 #define PL_MAKE_MEM_UNDEFINED(addr, size)
 130 #define PL_MAKE_MEM_DEFINED(addr, size)
 131
 132 #endif
 133
 134 /*
 135  * If the including .c file uses only one power-of-2 alignment, it may define
 136  * PL_ARENA_CONST_ALIGN_MASK to the alignment mask and save a few instructions
 137  * per ALLOCATE and GROW.
 138  */
 139 #ifdef PL_ARENA_CONST_ALIGN_MASK
 140 #define PL_ARENA_ALIGN(pool, n) (((PRUword)(n) + PL_ARENA_CONST_ALIGN_MASK) \
 141                                 & ~PL_ARENA_CONST_ALIGN_MASK)
 142
 143 #define PL_INIT_ARENA_POOL(pool, name, size) \
 144         PL_InitArenaPool(pool, name, size, PL_ARENA_CONST_ALIGN_MASK + 1)
 145 #else
 146 #define PL_ARENA_ALIGN(pool, n) (((PRUword)(n) + (pool)->mask) & ~(pool)->mask)
 147 #endif
 148
 149 #define PL_ARENA_ALLOCATE(p, pool, nb) \
 150     PR_BEGIN_MACRO \
 151         PLArena *_a = (pool)->current; \
 152         PRUint32 _nb = PL_ARENA_ALIGN(pool, (PRUint32)nb); \
 153         PRUword _p = _a->avail; \
 154         if (_nb < (PRUint32)nb) { \
 155             _p = 0; \
 156         } else if (_nb > (_a->limit - _a->avail)) { \
 157             _p = (PRUword)PL_ArenaAllocate(pool, _nb); \
 158         } else { \
 159             _a->avail += _nb; \
 160         } \
 161         p = (void *)_p; \
 162         if (p) { \
 163             PL_MAKE_MEM_UNDEFINED(p, (PRUint32)nb); \
 164             PL_ArenaCountAllocation(pool, (PRUint32)nb); \
 165         } \
 166     PR_END_MACRO
 167
 168 #define PL_ARENA_GROW(p, pool, size, incr) \
 169     PR_BEGIN_MACRO \
 170         PLArena *_a = (pool)->current; \
 171         PRUint32 _incr = PL_ARENA_ALIGN(pool, (PRUint32)incr); \
 172         if (_incr < (PRUint32)incr) { \
 173             p = NULL; \
 174         } else if (_a->avail == (PRUword)(p) + PL_ARENA_ALIGN(pool, size) && \
 175             _incr <= (_a->limit - _a->avail)) { \
 176             PL_MAKE_MEM_UNDEFINED((unsigned char *)(p) + size, (PRUint32)incr); \
 177             _a->avail += _incr; \
 178             PL_ArenaCountInplaceGrowth(pool, size, (PRUint32)incr); \
 179         } else { \
 180             p = PL_ArenaGrow(pool, p, size, (PRUint32)incr); \
 181         } \
 182         if (p) {\
 183             PL_ArenaCountGrowth(pool, size, (PRUint32)incr); \
 184         } \
 185     PR_END_MACRO
 186
 187 #define PL_ARENA_MARK(pool) ((void *) (pool)->current->avail)
 188 #define PR_UPTRDIFF(p,q) ((PRUword)(p) - (PRUword)(q))
 189
 190 #define PL_CLEAR_UNUSED_PATTERN(a, pattern) \
 191     PR_BEGIN_MACRO \
 192         PR_ASSERT((a)->avail <= (a)->limit); \
 193         PL_MAKE_MEM_UNDEFINED((void*)(a)->avail, (a)->limit - (a)->avail); \
 194         memset((void*)(a)->avail, (pattern), (a)->limit - (a)->avail); \
 195     PR_END_MACRO
 196 #ifdef DEBUG
 197 #define PL_FREE_PATTERN 0xDA
 198 #define PL_CLEAR_UNUSED(a) PL_CLEAR_UNUSED_PATTERN((a), PL_FREE_PATTERN)
 199 #define PL_CLEAR_ARENA(a) \
 200     PR_BEGIN_MACRO \
 201         PL_MAKE_MEM_UNDEFINED((void*)(a), (a)->limit - (PRUword)(a)); \
 202         memset((void*)(a), PL_FREE_PATTERN, (a)->limit - (PRUword)(a)); \
 203     PR_END_MACRO
 204 #else
 205 #define PL_CLEAR_UNUSED(a)
 206 #define PL_CLEAR_ARENA(a)
 207 #endif
 208
 209 #define PL_ARENA_RELEASE(pool, mark) \
 210     PR_BEGIN_MACRO \
 211         char *_m = (char *)(mark); \
 212         PLArena *_a = (pool)->current; \
 213         if (PR_UPTRDIFF(_m, _a->base) <= PR_UPTRDIFF(_a->avail, _a->base)) { \
 214             _a->avail = (PRUword)PL_ARENA_ALIGN(pool, _m); \
 215             PL_CLEAR_UNUSED(_a); \
 216             PL_MAKE_MEM_NOACCESS((void*)_a->avail, _a->limit - _a->avail); \
 217             PL_ArenaCountRetract(pool, _m); \
 218         } else { \
 219             PL_ArenaRelease(pool, _m); \
 220         } \
 221         PL_ArenaCountRelease(pool, _m); \
 222     PR_END_MACRO
 223
 224 #ifdef PL_ARENAMETER
 225 #define PL_COUNT_ARENA(pool,op) ((pool)->stats.narenas op)
 226 #else
 227 #define PL_COUNT_ARENA(pool,op)
 228 #endif
 229
 230 #define PL_ARENA_DESTROY(pool, a, pnext) \
 231     PR_BEGIN_MACRO \
 232         PL_COUNT_ARENA(pool,--); \
 233         if ((pool)->current == (a)) (pool)->current = &(pool)->first; \
 234         *(pnext) = (a)->next; \
 235         PL_CLEAR_ARENA(a); \
 236         free(a); \
 237         (a) = 0; \
 238     PR_END_MACRO
 239
 240 /*
 241 ** Initialize an arena pool with the given name for debugging and metering,
 242 ** with a minimum gross size per arena of size bytes.  The net size per arena
 243 ** is smaller than the gross size by a header of four pointers plus any
 244 ** necessary padding for alignment.
 245 **
 246 ** Note: choose a gross size that's a power of two to avoid the heap allocator
 247 ** rounding the size up.
 248 **/
 249 PR_EXTERN(void) PL_InitArenaPool(
 250     PLArenaPool *pool, const char *name, PRUint32 size, PRUint32 align);
 251
 252 /*
 253 ** Finish using arenas, freeing all memory associated with them.
 254 ** NOTE: this function is now a no-op. If you want to free a single
 255 ** PLArenaPoolUse use PL_FreeArenaPool() or PL_FinishArenaPool().
 256 **/
 257 PR_EXTERN(void) PL_ArenaFinish(void);
 258
 259 /*
 260 ** Free the arenas in pool.  The user may continue to allocate from pool
 261 ** after calling this function.  There is no need to call PL_InitArenaPool()
 262 ** again unless PL_FinishArenaPool(pool) has been called.
 263 **/
 264 PR_EXTERN(void) PL_FreeArenaPool(PLArenaPool *pool);
 265
 266 /*
 267 ** Free the arenas in pool and finish using it altogether.
 268 **/
 269 PR_EXTERN(void) PL_FinishArenaPool(PLArenaPool *pool);
 270
 271 /*
 272 ** Compact all of the arenas in a pool so that no space is wasted.
 273 ** NOT IMPLEMENTED.  Do not use.
 274 **/
 275 PR_EXTERN(void) PL_CompactArenaPool(PLArenaPool *pool);
 276
 277 /*
 278 ** Friend functions used by the PL_ARENA_*() macros.
 279 **
 280 ** WARNING: do not call these functions directly. Always use the
 281 ** PL_ARENA_*() macros.
 282 **/
 283 PR_EXTERN(void *) PL_ArenaAllocate(PLArenaPool *pool, PRUint32 nb);
 284
 285 PR_EXTERN(void *) PL_ArenaGrow(
 286     PLArenaPool *pool, void *p, PRUint32 size, PRUint32 incr);
 287
 288 PR_EXTERN(void) PL_ArenaRelease(PLArenaPool *pool, char *mark);
 289
 290 /*
 291 ** memset contents of all arenas in pool to pattern
 292 */
 293 PR_EXTERN(void) PL_ClearArenaPool(PLArenaPool *pool, PRInt32 pattern);
 294
 295 /*
 296 ** A function like malloc_size() or malloc_usable_size() that measures the
 297 ** size of a heap block.
 298 */
 299 typedef size_t (*PLMallocSizeFn)(const void *ptr);
 300
 301 /*
 302 ** Measure all memory used by a PLArenaPool, excluding the PLArenaPool
 303 ** structure.
 304 */
 305 PR_EXTERN(size_t) PL_SizeOfArenaPoolExcludingPool(
 306     const PLArenaPool *pool, PLMallocSizeFn mallocSizeOf);
 307
 308 #ifdef PL_ARENAMETER
 309
 310 #include <stdio.h>
 311
 312 PR_EXTERN(void) PL_ArenaCountAllocation(PLArenaPool *pool, PRUint32 nb);
 313
 314 PR_EXTERN(void) PL_ArenaCountInplaceGrowth(
 315     PLArenaPool *pool, PRUint32 size, PRUint32 incr);
 316
 317 PR_EXTERN(void) PL_ArenaCountGrowth(
 318     PLArenaPool *pool, PRUint32 size, PRUint32 incr);
 319
 320 PR_EXTERN(void) PL_ArenaCountRelease(PLArenaPool *pool, char *mark);
 321
 322 PR_EXTERN(void) PL_ArenaCountRetract(PLArenaPool *pool, char *mark);
 323
 324 PR_EXTERN(void) PL_DumpArenaStats(FILE *fp);
 325
 326 #else  /* !PL_ARENAMETER */
 327
 328 #define PL_ArenaCountAllocation(ap, nb)                 /* nothing */
 329 #define PL_ArenaCountInplaceGrowth(ap, size, incr)      /* nothing */
 330 #define PL_ArenaCountGrowth(ap, size, incr)             /* nothing */
 331 #define PL_ArenaCountRelease(ap, mark)                  /* nothing */
 332 #define PL_ArenaCountRetract(ap, mark)                  /* nothing */
 333
 334 #endif /* !PL_ARENAMETER */
 335
 336 PR_END_EXTERN_C
 337
 338 #endif /* plarena_h___ */