/* Allocates one element from the pool specified. */
void *
pool_alloc (alloc_pool pool)
{
alloc_pool_list header;
char *block;
#ifdef GATHER_STATISTICS
struct alloc_pool_descriptor *desc = alloc_pool_descriptor (pool->name);
desc->allocated+=pool->elt_size;
#endif
gcc_assert (pool);
/* If there are no more free elements, make some more!. */
if (!pool->free_list)
{
size_t i;
alloc_pool_list block_header;
/* Make the block. */
block = XNEWVEC (char, pool->block_size);
block_header = (alloc_pool_list) block;
block += align_eight (sizeof (struct alloc_pool_list_def));
#ifdef GATHER_STATISTICS
desc->current += pool->block_size;
if (desc->peak < desc->current)
desc->peak = desc->current;
#endif
/* Throw it on the block list. */
block_header->next = pool->block_list;
pool->block_list = block_header;
/* Now put the actual block pieces onto the free list. */
for (i = 0; i < pool->elts_per_block; i++, block += pool->elt_size)
{
#ifdef ENABLE_CHECKING
/* Mark the element to be free. */
((allocation_object *) block)->id = 0;
#endif
header = (alloc_pool_list) USER_PTR_FROM_ALLOCATION_OBJECT_PTR (block);
header->next = pool->free_list;
pool->free_list = header;
}
/* Also update the number of elements we have free/allocated, and
increment the allocated block count. */
pool->elts_allocated += pool->elts_per_block;
pool->elts_free += pool->elts_per_block;
pool->blocks_allocated += 1;
}
/* Make the block available for allocation. */
pool->virgin_free_list = block;
pool->virgin_elts_remaining = pool->elts_per_block;
/* Also update the number of elements we have free/allocated, and
increment the allocated block count. */
pool->elts_allocated += pool->elts_per_block;
pool->elts_free += pool->elts_per_block;
pool->blocks_allocated += 1;
}
/* We now know that we can take the first elt off the virgin list and
put it on the returned list. */
block = pool->virgin_free_list;
header = (alloc_pool_list) USER_PTR_FROM_ALLOCATION_OBJECT_PTR (block);
header->next = NULL;
#ifdef ENABLE_CHECKING
/* Mark the element to be free. */
((allocation_object *) block)->id = 0;
#endif
VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (header,size));
pool->returned_free_list = header;
pool->virgin_free_list += pool->elt_size;
pool->virgin_elts_remaining--;
}
/* Pull the first free element from the free list, and return it. */
header = pool->returned_free_list;
VALGRIND_DISCARD (VALGRIND_MAKE_MEM_DEFINED (header, sizeof (*header)));
