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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
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#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.
+ * See https://github.com/google/sanitizers/wiki/AddressSanitizerManualPoisoning
+ */
+
+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___ */