PR_IMPLEMENT(void) PL_InitArenaPool(
PLArenaPool *pool, const char *name, PRUint32 size, PRUint32 align)
{
/*
* Look-up table of PR_BITMASK(PR_CeilingLog2(align)) values for
* align = 1 to 32.
*/
static const PRUint8 pmasks[33] = {
0, /* not used */
0, 1, 3, 3, 7, 7, 7, 7,15,15,15,15,15,15,15,15, /* 1 ... 16 */
31,31,31,31,31,31,31,31,31,31,31,31,31,31,31,31}; /* 17 ... 32 */
if (align == 0)
align = PL_ARENA_DEFAULT_ALIGN;
if (align < sizeof(pmasks)/sizeof(pmasks[0]))
pool->mask = pmasks[align];
else
pool->mask = PR_BITMASK(PR_CeilingLog2(align));
pool->first.next = NULL;
pool->first.base = pool->first.avail = pool->first.limit =
(PRUword)PL_ARENA_ALIGN(pool, &pool->first + 1);
pool->current = &pool->first;
pool->arenasize = size;
#ifdef PL_ARENAMETER
memset(&pool->stats, 0, sizeof pool->stats);
pool->stats.name = strdup(name);
pool->stats.next = arena_stats_list;
arena_stats_list = &pool->stats;
#endif
}
PR_IMPLEMENT(void) PL_InitArenaPool(
PLArenaPool *pool, const char *name, PRUint32 size, PRUint32 align)
{
#if defined(XP_MAC)
#pragma unused (name)
#endif
if (align == 0)
align = PL_ARENA_DEFAULT_ALIGN;
pool->mask = PR_BITMASK(PR_CeilingLog2(align));
pool->first.next = NULL;
/* Set all three addresses in pool->first to the same dummy value.
* These addresses are only compared with each other, but never
* dereferenced. */
pool->first.base = pool->first.avail = pool->first.limit =
(PRUword)PL_ARENA_ALIGN(pool, &pool->first + 1);
pool->current = &pool->first;
pool->arenasize = size;
#ifdef PL_ARENAMETER
memset(&pool->stats, 0, sizeof pool->stats);
pool->stats.name = strdup(name);
pool->stats.next = arena_stats_list;
arena_stats_list = &pool->stats;
#endif
}
void*
nsPresArena::Allocate(uint32_t aCode, size_t aSize)
{
NS_ABORT_IF_FALSE(aSize > 0, "PresArena cannot allocate zero bytes");
// We only hand out aligned sizes
aSize = PL_ARENA_ALIGN(&mPool, aSize);
// If there is no free-list entry for this type already, we have
// to create one now, to record its size.
FreeList* list = mFreeLists.PutEntry(aCode);
nsTArray<void*>::index_type len = list->mEntries.Length();
if (list->mEntrySize == 0) {
NS_ABORT_IF_FALSE(len == 0, "list with entries but no recorded size");
list->mEntrySize = aSize;
} else {
NS_ABORT_IF_FALSE(list->mEntrySize == aSize,
"different sizes for same object type code");
}
void* result;
if (len > 0) {
// LIFO behavior for best cache utilization
result = list->mEntries.ElementAt(len - 1);
list->mEntries.RemoveElementAt(len - 1);
#if defined(DEBUG)
{
MOZ_MAKE_MEM_DEFINED(result, list->mEntrySize);
char* p = reinterpret_cast<char*>(result);
char* limit = p + list->mEntrySize;
for (; p < limit; p += sizeof(uintptr_t)) {
uintptr_t val = *reinterpret_cast<uintptr_t*>(p);
NS_ABORT_IF_FALSE(val == mozPoisonValue(),
nsPrintfCString("PresArena: poison overwritten; "
"wanted %.16llx "
"found %.16llx "
"errors in bits %.16llx",
uint64_t(mozPoisonValue()),
uint64_t(val),
uint64_t(mozPoisonValue() ^ val)
).get());
}
}
#endif
MOZ_MAKE_MEM_UNDEFINED(result, list->mEntrySize);
return result;
}
// Allocate a new chunk from the arena
list->mEntriesEverAllocated++;
PL_ARENA_ALLOCATE(result, &mPool, aSize);
if (!result) {
NS_ABORT_OOM(aSize);
}
return result;
}
void* Allocate(PRUint32 aCode, size_t aSize)
{
NS_ABORT_IF_FALSE(aSize > 0, "PresArena cannot allocate zero bytes");
// We only hand out aligned sizes
aSize = PL_ARENA_ALIGN(&mPool, aSize);
// If there is no free-list entry for this type already, we have
// to create one now, to record its size.
FreeList* list = mFreeLists.PutEntry(aCode);
if (!list) {
return nsnull;
}
nsTArray<void*>::index_type len = list->mEntries.Length();
if (list->mEntrySize == 0) {
NS_ABORT_IF_FALSE(len == 0, "list with entries but no recorded size");
list->mEntrySize = aSize;
} else {
NS_ABORT_IF_FALSE(list->mEntrySize == aSize,
"different sizes for same object type code");
}
void* result;
if (len > 0) {
// LIFO behavior for best cache utilization
result = list->mEntries.ElementAt(len - 1);
list->mEntries.RemoveElementAt(len - 1);
#ifdef DEBUG
{
char* p = reinterpret_cast<char*>(result);
char* limit = p + list->mEntrySize;
for (; p < limit; p += sizeof(PRUword)) {
NS_ABORT_IF_FALSE(*reinterpret_cast<PRUword*>(p) == ARENA_POISON,
"PresArena: poison overwritten");
}
}
#endif
return result;
}
// Allocate a new chunk from the arena
PL_ARENA_ALLOCATE(result, &mPool, aSize);
return result;
}
PR_IMPLEMENT(void) PL_InitArenaPool(
PLArenaPool *pool, const char *name, PRUint32 size, PRUint32 align)
{
#if !defined (__GNUC__)
#pragma unused (name)
#endif
if (align == 0)
align = PL_ARENA_DEFAULT_ALIGN;
pool->mask = PR_BITMASK(PR_CeilingLog2(align));
pool->first.next = NULL;
pool->first.base = pool->first.avail = pool->first.limit =
(PRUword)PL_ARENA_ALIGN(pool, &pool->first + 1);
pool->current = &pool->first;
pool->arenasize = size;
#ifdef PL_ARENAMETER
memset(&pool->stats, 0, sizeof pool->stats);
pool->stats.name = strdup(name);
pool->stats.next = arena_stats_list;
arena_stats_list = &pool->stats;
#endif
}
PR_IMPLEMENT(void *) PL_ArenaAllocate(PLArenaPool *pool, PRUint32 nb)
{
PLArena *a;
char *rp; /* returned pointer */
PR_ASSERT((nb & pool->mask) == 0);
nb = (PRUword)PL_ARENA_ALIGN(pool, nb); /* force alignment */
/* attempt to allocate from arenas at pool->current */
{
a = pool->current;
do {
if ( a->avail +nb <= a->limit ) {
pool->current = a;
rp = (char *)a->avail;
a->avail += nb;
return rp;
}
} while( NULL != (a = a->next) );
}
/* attempt to allocate from arena_freelist */
{
PLArena *p; /* previous pointer, for unlinking from freelist */
/* lock the arena_freelist. Make access to the freelist MT-Safe */
if ( PR_FAILURE == LockArena())
return(0);
for ( a = arena_freelist, p = NULL; a != NULL ; p = a, a = a->next ) {
if ( a->base +nb <= a->limit ) {
if ( p == NULL )
arena_freelist = a->next;
else
p->next = a->next;
UnlockArena();
a->avail = a->base;
rp = (char *)a->avail;
a->avail += nb;
/* the newly allocated arena is linked after pool->current
* and becomes pool->current */
a->next = pool->current->next;
pool->current->next = a;
pool->current = a;
if ( NULL == pool->first.next )
pool->first.next = a;
return(rp);
}
}
UnlockArena();
}
/* attempt to allocate from the heap */
{
PRUint32 sz = PR_MAX(pool->arenasize, nb);
sz += sizeof *a + pool->mask; /* header and alignment slop */
a = (PLArena*)PR_MALLOC(sz);
if ( NULL != a ) {
a->limit = (PRUword)a + sz;
a->base = a->avail = (PRUword)PL_ARENA_ALIGN(pool, a + 1);
rp = (char *)a->avail;
a->avail += nb;
/* the newly allocated arena is linked after pool->current
* and becomes pool->current */
a->next = pool->current->next;
pool->current->next = a;
pool->current = a;
if ( NULL == pool->first.next )
pool->first.next = a;
PL_COUNT_ARENA(pool,++);
COUNT(pool, nmallocs);
return(rp);
}
}
PR_IMPLEMENT(void *) PL_ArenaAllocate(PLArenaPool *pool, PRUint32 nb)
{
PLArena *a;
char *rp; /* returned pointer */
PR_ASSERT((nb & pool->mask) == 0);
#ifdef __APPLE__
nb = PL_ARENA_ALIGN(pool, nb); /* force alignment, cast is useless/causes warning. */
#else
nb = (PRUword)PL_ARENA_ALIGN(pool, nb); /* force alignment */
#endif
/* attempt to allocate from arenas at pool->current */
{
a = pool->current;
do {
if ( nb <= a->limit - a->avail ) {
pool->current = a;
rp = (char *)a->avail;
a->avail += nb;
return rp;
}
} while( NULL != (a = a->next) );
}
/* attempt to allocate from the heap */
{
PRUint32 sz = PR_MAX(pool->arenasize, nb);
if (PR_UINT32_MAX - sz < sizeof *a + pool->mask) {
a = NULL;
} else {
sz += sizeof *a + pool->mask; /* header and alignment slop */
a = (PLArena*)PR_MALLOC(sz);
}
#ifdef __APPLE__
// Check for integer overflow on a->avail += nb
PRUword a_avail_tmp=(PRUword)PL_ARENA_ALIGN(pool, a + 1);
if (a_avail_tmp + nb < a_avail_tmp)
{
PR_FREEIF(a); // Set a back to NULL
}
#endif
if ( NULL != a ) {
a->limit = (PRUword)a + sz;
#ifdef __APPLE__
a->base = a->avail = a_avail_tmp;
#else
a->base = a->avail = (PRUword)PL_ARENA_ALIGN(pool, a + 1);
#endif
rp = (char *)a->avail;
a->avail += nb;
/* the newly allocated arena is linked after pool->current
* and becomes pool->current */
a->next = pool->current->next;
pool->current->next = a;
pool->current = a;
if ( NULL == pool->first.next )
pool->first.next = a;
PL_COUNT_ARENA(pool,++);
COUNT(pool, nmallocs);
return(rp);
}
}
