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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#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"
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
typedef struct PLArenaPool PLArenaPool;
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
};
/*
* WARNING: The PL_MAKE_MEM_ macros are for internal use by NSPR. Do NOT use
* them in your code.
*
* NOTE: Valgrind support to be added.
*
* The PL_MAKE_MEM_ macros are modeled after the MOZ_MAKE_MEM_ macros in
* Mozilla's mfbt/MemoryChecking.h. Only AddressSanitizer is supported now.
*
* Provides a common interface to the ASan (AddressSanitizer) and Valgrind
* functions used to mark memory in certain ways. In detail, the following
* three macros are provided:
*
* PL_MAKE_MEM_NOACCESS - Mark memory as unsafe to access (e.g. freed)
* PL_MAKE_MEM_UNDEFINED - Mark memory as accessible, with content undefined
* PL_MAKE_MEM_DEFINED - Mark memory as accessible, with content defined
*
* With Valgrind in use, these directly map to the three respective Valgrind
* macros. With ASan in use, the NOACCESS macro maps to poisoning the memory,
* while the UNDEFINED/DEFINED macros unpoison memory.
*
* With no memory checker available, all macros expand to the empty statement.
*/
/* WARNING: PL_SANITIZE_ADDRESS is for internal use by this header. Do NOT
* define or test this macro in your code.
*/
#if defined(__has_feature)
#if __has_feature(address_sanitizer)
#define PL_SANITIZE_ADDRESS 1
#endif
#elif defined(__SANITIZE_ADDRESS__)
#define PL_SANITIZE_ADDRESS 1
#endif
#if defined(PL_SANITIZE_ADDRESS)
#if defined(_MSC_VER)
/* We can't use dllimport due to DLL linkage mismatch with
* sanitizer/asan_interface.h.
*/
#define PL_ASAN_VISIBILITY(type_) type_
#else
#define PL_ASAN_VISIBILITY(type_) PR_IMPORT(type_)
#endif
/* These definitions are usually provided through the
* sanitizer/asan_interface.h header installed by ASan.
*/
PL_ASAN_VISIBILITY(void) __asan_poison_memory_region(
void const volatile *addr, size_t size);
PL_ASAN_VISIBILITY(void) __asan_unpoison_memory_region(
void const volatile *addr, size_t size);
#define PL_MAKE_MEM_NOACCESS(addr, size) \
__asan_poison_memory_region((addr), (size))
#define PL_MAKE_MEM_UNDEFINED(addr, size) \
__asan_unpoison_memory_region((addr), (size))
#define PL_MAKE_MEM_DEFINED(addr, size) \
__asan_unpoison_memory_region((addr), (size))
#else
#define PL_MAKE_MEM_NOACCESS(addr, size)
#define PL_MAKE_MEM_UNDEFINED(addr, size)
#define PL_MAKE_MEM_DEFINED(addr, size)
#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, (PRUint32)nb); \
PRUword _p = _a->avail; \
if (_nb < (PRUint32)nb) { \
_p = 0; \
} else if (_nb > (_a->limit - _a->avail)) { \
_p = (PRUword)PL_ArenaAllocate(pool, _nb); \
} else { \
_a->avail += _nb; \
} \
p = (void *)_p; \
if (p) { \
PL_MAKE_MEM_UNDEFINED(p, (PRUint32)nb); \
PL_ArenaCountAllocation(pool, (PRUint32)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, (PRUint32)incr); \
if (_incr < (PRUint32)incr) { \
p = NULL; \
} else if (_a->avail == (PRUword)(p) + PL_ARENA_ALIGN(pool, size) && \
_incr <= (_a->limit - _a->avail)) { \
PL_MAKE_MEM_UNDEFINED((unsigned char *)(p) + size, (PRUint32)incr); \
_a->avail += _incr; \
PL_ArenaCountInplaceGrowth(pool, size, (PRUint32)incr); \
} else { \
p = PL_ArenaGrow(pool, p, size, (PRUint32)incr); \
} \
if (p) {\
PL_ArenaCountGrowth(pool, size, (PRUint32)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_BEGIN_MACRO \
PR_ASSERT((a)->avail <= (a)->limit); \
PL_MAKE_MEM_UNDEFINED((void*)(a)->avail, (a)->limit - (a)->avail); \
memset((void*)(a)->avail, (pattern), (a)->limit - (a)->avail); \
PR_END_MACRO
#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) \
PR_BEGIN_MACRO \
PL_MAKE_MEM_UNDEFINED((void*)(a), (a)->limit - (PRUword)(a)); \
memset((void*)(a), PL_FREE_PATTERN, (a)->limit - (PRUword)(a)); \
PR_END_MACRO
#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_MAKE_MEM_NOACCESS((void*)_a->avail, _a->limit - _a->avail); \
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
/*
** Initialize an arena pool with the given name for debugging and metering,
** with a minimum gross size per arena of size bytes. The net size per arena
** is smaller than the gross size by a header of four pointers plus any
** necessary padding for alignment.
**
** Note: choose a gross size that's a power of two to avoid the heap allocator
** rounding the size up.
**/
PR_EXTERN(void) PL_InitArenaPool(
PLArenaPool *pool, const char *name, PRUint32 size, PRUint32 align);
/*
** Finish using arenas, freeing all memory associated with them.
** NOTE: this function is now a no-op. If you want to free a single
** PLArenaPoolUse use PL_FreeArenaPool() or PL_FinishArenaPool().
**/
PR_EXTERN(void) PL_ArenaFinish(void);
/*
** Free the arenas in pool. The user may continue to allocate from pool
** after calling this function. There is no need to call PL_InitArenaPool()
** again unless PL_FinishArenaPool(pool) has been called.
**/
PR_EXTERN(void) PL_FreeArenaPool(PLArenaPool *pool);
/*
** Free the arenas in pool and finish using it altogether.
**/
PR_EXTERN(void) PL_FinishArenaPool(PLArenaPool *pool);
/*
** Compact all of the arenas in a pool so that no space is wasted.
** NOT IMPLEMENTED. Do not use.
**/
PR_EXTERN(void) PL_CompactArenaPool(PLArenaPool *pool);
/*
** Friend functions used by the PL_ARENA_*() macros.
**
** WARNING: do not call these functions directly. Always use the
** PL_ARENA_*() macros.
**/
PR_EXTERN(void *) PL_ArenaAllocate(PLArenaPool *pool, PRUint32 nb);
PR_EXTERN(void *) PL_ArenaGrow(
PLArenaPool *pool, void *p, PRUint32 size, PRUint32 incr);
PR_EXTERN(void) PL_ArenaRelease(PLArenaPool *pool, char *mark);
/*
** memset contents of all arenas in pool to pattern
*/
PR_EXTERN(void) PL_ClearArenaPool(PLArenaPool *pool, PRInt32 pattern);
/*
** A function like malloc_size() or malloc_usable_size() that measures the
** size of a heap block.
*/
typedef size_t (*PLMallocSizeFn)(const void *ptr);
/*
** Measure all memory used by a PLArenaPool, excluding the PLArenaPool
** structure.
*/
PR_EXTERN(size_t) PL_SizeOfArenaPoolExcludingPool(
const PLArenaPool *pool, PLMallocSizeFn mallocSizeOf);
#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___ */