andre@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
andre@0: /* This Source Code Form is subject to the terms of the Mozilla Public
andre@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
andre@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
andre@0: 
andre@0: #ifndef plarena_h___
andre@0: #define plarena_h___
andre@0: /*
andre@0:  * Lifetime-based fast allocation, inspired by much prior art, including
andre@0:  * "Fast Allocation and Deallocation of Memory Based on Object Lifetimes"
andre@0:  * David R. Hanson, Software -- Practice and Experience, Vol. 20(1).
andre@0:  *
andre@0:  * Also supports LIFO allocation (PL_ARENA_MARK/PL_ARENA_RELEASE).
andre@0:  */
andre@0: #include "prtypes.h"
andre@0: #include "plarenas.h"
andre@0: 
andre@0: PR_BEGIN_EXTERN_C
andre@0: 
andre@0: typedef struct PLArena          PLArena;
andre@0: 
andre@0: struct PLArena {
andre@0:     PLArena     *next;          /* next arena for this lifetime */
andre@0:     PRUword     base;           /* aligned base address, follows this header */
andre@0:     PRUword     limit;          /* one beyond last byte in arena */
andre@0:     PRUword     avail;          /* points to next available byte */
andre@0: };
andre@0: 
andre@0: #ifdef PL_ARENAMETER
andre@0: typedef struct PLArenaStats PLArenaStats;
andre@0: 
andre@0: struct PLArenaStats {
andre@0:     PLArenaStats  *next;        /* next in arenaStats list */
andre@0:     char          *name;        /* name for debugging */
andre@0:     PRUint32      narenas;      /* number of arenas in pool */
andre@0:     PRUint32      nallocs;      /* number of PL_ARENA_ALLOCATE() calls */
andre@0:     PRUint32      nreclaims;    /* number of reclaims from freeArenas */
andre@0:     PRUint32      nmallocs;     /* number of malloc() calls */
andre@0:     PRUint32      ndeallocs;    /* number of lifetime deallocations */
andre@0:     PRUint32      ngrows;       /* number of PL_ARENA_GROW() calls */
andre@0:     PRUint32      ninplace;     /* number of in-place growths */
andre@0:     PRUint32      nreleases;    /* number of PL_ARENA_RELEASE() calls */
andre@0:     PRUint32      nfastrels;    /* number of "fast path" releases */
andre@0:     PRUint32      nbytes;       /* total bytes allocated */
andre@0:     PRUint32      maxalloc;     /* maximum allocation size in bytes */
andre@0:     PRFloat64     variance;     /* size variance accumulator */
andre@0: };
andre@0: #endif
andre@0: 
andre@0: struct PLArenaPool {
andre@0:     PLArena     first;          /* first arena in pool list */
andre@0:     PLArena     *current;       /* arena from which to allocate space */
andre@0:     PRUint32    arenasize;      /* net exact size of a new arena */
andre@0:     PRUword     mask;           /* alignment mask (power-of-2 - 1) */
andre@0: #ifdef PL_ARENAMETER
andre@0:     PLArenaStats stats;
andre@0: #endif
andre@0: };
andre@0: 
andre@0: /*
andre@0:  * WARNING: The PL_MAKE_MEM_ macros are for internal use by NSPR. Do NOT use
andre@0:  * them in your code.
andre@0:  *
andre@0:  * NOTE: Valgrind support to be added.
andre@0:  *
andre@0:  * The PL_MAKE_MEM_ macros are modeled after the MOZ_MAKE_MEM_ macros in
andre@0:  * Mozilla's mfbt/MemoryChecking.h. Only AddressSanitizer is supported now.
andre@0:  *
andre@0:  * Provides a common interface to the ASan (AddressSanitizer) and Valgrind
andre@0:  * functions used to mark memory in certain ways. In detail, the following
andre@0:  * three macros are provided:
andre@0:  *
andre@0:  *   PL_MAKE_MEM_NOACCESS  - Mark memory as unsafe to access (e.g. freed)
andre@0:  *   PL_MAKE_MEM_UNDEFINED - Mark memory as accessible, with content undefined
andre@0:  *   PL_MAKE_MEM_DEFINED - Mark memory as accessible, with content defined
andre@0:  *
andre@0:  * With Valgrind in use, these directly map to the three respective Valgrind
andre@0:  * macros. With ASan in use, the NOACCESS macro maps to poisoning the memory,
andre@0:  * while the UNDEFINED/DEFINED macros unpoison memory.
andre@0:  *
andre@0:  * With no memory checker available, all macros expand to the empty statement.
andre@0:  */
andre@0: 
andre@0: /* WARNING: PL_SANITIZE_ADDRESS is for internal use by this header. Do NOT
andre@0:  * define or test this macro in your code.
andre@0:  */
andre@0: #if defined(__has_feature)
andre@0: #if __has_feature(address_sanitizer)
andre@0: #define PL_SANITIZE_ADDRESS 1
andre@0: #endif
andre@0: #elif defined(__SANITIZE_ADDRESS__)
andre@0: #define PL_SANITIZE_ADDRESS 1
andre@0: #endif
andre@0: 
andre@0: #if defined(PL_SANITIZE_ADDRESS)
andre@0: 
andre@0: /* These definitions are usually provided through the
andre@0:  * sanitizer/asan_interface.h header installed by ASan.
andre@0:  * See https://code.google.com/p/address-sanitizer/wiki/ManualPoisoning
andre@0:  */
andre@0: 
andre@0: void __asan_poison_memory_region(void const volatile *addr, size_t size);
andre@0: void __asan_unpoison_memory_region(void const volatile *addr, size_t size);
andre@0: 
andre@0: #define PL_MAKE_MEM_NOACCESS(addr, size) \
andre@0:     __asan_poison_memory_region((addr), (size))
andre@0: 
andre@0: #define PL_MAKE_MEM_UNDEFINED(addr, size) \
andre@0:     __asan_unpoison_memory_region((addr), (size))
andre@0: 
andre@0: #define PL_MAKE_MEM_DEFINED(addr, size) \
andre@0:     __asan_unpoison_memory_region((addr), (size))
andre@0: 
andre@0: #else
andre@0: 
andre@0: #define PL_MAKE_MEM_NOACCESS(addr, size)
andre@0: #define PL_MAKE_MEM_UNDEFINED(addr, size)
andre@0: #define PL_MAKE_MEM_DEFINED(addr, size)
andre@0: 
andre@0: #endif
andre@0: 
andre@0: /*
andre@0:  * If the including .c file uses only one power-of-2 alignment, it may define
andre@0:  * PL_ARENA_CONST_ALIGN_MASK to the alignment mask and save a few instructions
andre@0:  * per ALLOCATE and GROW.
andre@0:  */
andre@0: #ifdef PL_ARENA_CONST_ALIGN_MASK
andre@0: #define PL_ARENA_ALIGN(pool, n) (((PRUword)(n) + PL_ARENA_CONST_ALIGN_MASK) \
andre@0:                                 & ~PL_ARENA_CONST_ALIGN_MASK)
andre@0: 
andre@0: #define PL_INIT_ARENA_POOL(pool, name, size) \
andre@0:         PL_InitArenaPool(pool, name, size, PL_ARENA_CONST_ALIGN_MASK + 1)
andre@0: #else
andre@0: #define PL_ARENA_ALIGN(pool, n) (((PRUword)(n) + (pool)->mask) & ~(pool)->mask)
andre@0: #endif
andre@0: 
andre@0: #define PL_ARENA_ALLOCATE(p, pool, nb) \
andre@0:     PR_BEGIN_MACRO \
andre@0:         PLArena *_a = (pool)->current; \
andre@0:         PRUint32 _nb = PL_ARENA_ALIGN(pool, nb); \
andre@0:         PRUword _p = _a->avail; \
andre@0:         PRUword _q = _p + _nb; \
andre@0:         if (_q > _a->limit) { \
andre@0:             _p = (PRUword)PL_ArenaAllocate(pool, _nb); \
andre@0:         } else { \
andre@0:             _a->avail = _q; \
andre@0:         } \
andre@0:         p = (void *)_p; \
andre@0:         PL_MAKE_MEM_UNDEFINED(p, nb); \
andre@0:         PL_ArenaCountAllocation(pool, nb); \
andre@0:     PR_END_MACRO
andre@0: 
andre@0: #define PL_ARENA_GROW(p, pool, size, incr) \
andre@0:     PR_BEGIN_MACRO \
andre@0:         PLArena *_a = (pool)->current; \
andre@0:         PRUint32 _incr = PL_ARENA_ALIGN(pool, incr); \
andre@0:         PRUword _p = _a->avail; \
andre@0:         PRUword _q = _p + _incr; \
andre@0:         if (_p == (PRUword)(p) + PL_ARENA_ALIGN(pool, size) && \
andre@0:             _q <= _a->limit) { \
andre@0:             PL_MAKE_MEM_UNDEFINED((unsigned char *)(p) + size, incr); \
andre@0:             _a->avail = _q; \
andre@0:             PL_ArenaCountInplaceGrowth(pool, size, incr); \
andre@0:         } else { \
andre@0:             p = PL_ArenaGrow(pool, p, size, incr); \
andre@0:         } \
andre@0:         PL_ArenaCountGrowth(pool, size, incr); \
andre@0:     PR_END_MACRO
andre@0: 
andre@0: #define PL_ARENA_MARK(pool) ((void *) (pool)->current->avail)
andre@0: #define PR_UPTRDIFF(p,q) ((PRUword)(p) - (PRUword)(q))
andre@0: 
andre@0: #define PL_CLEAR_UNUSED_PATTERN(a, pattern) \
andre@0:     PR_BEGIN_MACRO \
andre@0:         PR_ASSERT((a)->avail <= (a)->limit); \
andre@0:         PL_MAKE_MEM_UNDEFINED((void*)(a)->avail, (a)->limit - (a)->avail); \
andre@0:         memset((void*)(a)->avail, (pattern), (a)->limit - (a)->avail); \
andre@0:     PR_END_MACRO
andre@0: #ifdef DEBUG
andre@0: #define PL_FREE_PATTERN 0xDA
andre@0: #define PL_CLEAR_UNUSED(a) PL_CLEAR_UNUSED_PATTERN((a), PL_FREE_PATTERN)
andre@0: #define PL_CLEAR_ARENA(a) \
andre@0:     PR_BEGIN_MACRO \
andre@0:         PL_MAKE_MEM_UNDEFINED((void*)(a), (a)->limit - (PRUword)(a)); \
andre@0:         memset((void*)(a), PL_FREE_PATTERN, (a)->limit - (PRUword)(a)); \
andre@0:     PR_END_MACRO
andre@0: #else
andre@0: #define PL_CLEAR_UNUSED(a)
andre@0: #define PL_CLEAR_ARENA(a)
andre@0: #endif
andre@0: 
andre@0: #define PL_ARENA_RELEASE(pool, mark) \
andre@0:     PR_BEGIN_MACRO \
andre@0:         char *_m = (char *)(mark); \
andre@0:         PLArena *_a = (pool)->current; \
andre@0:         if (PR_UPTRDIFF(_m, _a->base) <= PR_UPTRDIFF(_a->avail, _a->base)) { \
andre@0:             _a->avail = (PRUword)PL_ARENA_ALIGN(pool, _m); \
andre@0:             PL_CLEAR_UNUSED(_a); \
andre@0:             PL_MAKE_MEM_NOACCESS((void*)_a->avail, _a->limit - _a->avail); \
andre@0:             PL_ArenaCountRetract(pool, _m); \
andre@0:         } else { \
andre@0:             PL_ArenaRelease(pool, _m); \
andre@0:         } \
andre@0:         PL_ArenaCountRelease(pool, _m); \
andre@0:     PR_END_MACRO
andre@0: 
andre@0: #ifdef PL_ARENAMETER
andre@0: #define PL_COUNT_ARENA(pool,op) ((pool)->stats.narenas op)
andre@0: #else
andre@0: #define PL_COUNT_ARENA(pool,op)
andre@0: #endif
andre@0: 
andre@0: #define PL_ARENA_DESTROY(pool, a, pnext) \
andre@0:     PR_BEGIN_MACRO \
andre@0:         PL_COUNT_ARENA(pool,--); \
andre@0:         if ((pool)->current == (a)) (pool)->current = &(pool)->first; \
andre@0:         *(pnext) = (a)->next; \
andre@0:         PL_CLEAR_ARENA(a); \
andre@0:         free(a); \
andre@0:         (a) = 0; \
andre@0:     PR_END_MACRO
andre@0: 
andre@0: #ifdef PL_ARENAMETER
andre@0: 
andre@0: #include <stdio.h>
andre@0: 
andre@0: PR_EXTERN(void) PL_ArenaCountAllocation(PLArenaPool *pool, PRUint32 nb);
andre@0: 
andre@0: PR_EXTERN(void) PL_ArenaCountInplaceGrowth(
andre@0:     PLArenaPool *pool, PRUint32 size, PRUint32 incr);
andre@0: 
andre@0: PR_EXTERN(void) PL_ArenaCountGrowth(
andre@0:     PLArenaPool *pool, PRUint32 size, PRUint32 incr);
andre@0: 
andre@0: PR_EXTERN(void) PL_ArenaCountRelease(PLArenaPool *pool, char *mark);
andre@0: 
andre@0: PR_EXTERN(void) PL_ArenaCountRetract(PLArenaPool *pool, char *mark);
andre@0: 
andre@0: PR_EXTERN(void) PL_DumpArenaStats(FILE *fp);
andre@0: 
andre@0: #else  /* !PL_ARENAMETER */
andre@0: 
andre@0: #define PL_ArenaCountAllocation(ap, nb)                 /* nothing */
andre@0: #define PL_ArenaCountInplaceGrowth(ap, size, incr)      /* nothing */
andre@0: #define PL_ArenaCountGrowth(ap, size, incr)             /* nothing */
andre@0: #define PL_ArenaCountRelease(ap, mark)                  /* nothing */
andre@0: #define PL_ArenaCountRetract(ap, mark)                  /* nothing */
andre@0: 
andre@0: #endif /* !PL_ARENAMETER */
andre@0: 
andre@0: PR_END_EXTERN_C
andre@0: 
andre@0: #endif /* plarena_h___ */