/* Functions to support a pool of allocatable objects.
- Copyright (C) 1987, 1997, 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
+ Copyright (C) 1987, 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2006,
+ 2007, 2008 Free Software Foundation, Inc.
Contributed by Daniel Berlin <dan@cgsoftware.com>
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
-Software Foundation; either version 2, or (at your option) any later
+Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
for more details.
You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING. If not, write to the Free
-Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-02111-1307, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
#include "alloc-pool.h"
+#include "hashtab.h"
-#define align_four(x) (((x+3) >> 2) << 2)
#define align_eight(x) (((x+7) >> 3) << 3)
+/* The internal allocation object. */
+typedef struct allocation_object_def
+{
+#ifdef ENABLE_CHECKING
+ /* The ID of alloc pool which the object was allocated from. */
+ ALLOC_POOL_ID_TYPE id;
+#endif
+
+ union
+ {
+ /* The data of the object. */
+ char data[1];
+
+ /* Because we want any type of data to be well aligned after the ID,
+ the following elements are here. They are never accessed so
+ the allocated object may be even smaller than this structure. */
+ char *align_p;
+ HOST_WIDEST_INT align_i;
+ long double align_ld;
+ } u;
+} allocation_object;
+
+/* Convert a pointer to allocation_object from a pointer to user data. */
+#define ALLOCATION_OBJECT_PTR_FROM_USER_PTR(X) \
+ ((allocation_object *) (((char *) (X)) \
+ - offsetof (allocation_object, u.data)))
+
+/* Convert a pointer to user data from a pointer to allocation_object. */
+#define USER_PTR_FROM_ALLOCATION_OBJECT_PTR(X) \
+ ((void *) (((allocation_object *) (X))->u.data))
+
+#ifdef ENABLE_CHECKING
+/* Last used ID. */
+static ALLOC_POOL_ID_TYPE last_id;
+#endif
+
+#ifdef GATHER_STATISTICS
+
+/* Store information about each particular alloc_pool. Note that this
+ will underestimate the amount the amount of storage used by a small amount:
+ 1) The overhead in a pool is not accounted for.
+ 2) The unallocated elements in a block are not accounted for. Note
+ that this can at worst case be one element smaller that the block
+ size for that pool. */
+struct alloc_pool_descriptor
+{
+ const char *name;
+ /* Number of pools allocated. */
+ unsigned long created;
+ /* Gross allocated storage. */
+ unsigned long allocated;
+ /* Amount of currently active storage. */
+ unsigned long current;
+ /* Peak amount of storage used. */
+ unsigned long peak;
+ /* Size of element in the pool. */
+ int elt_size;
+};
+
+/* Hashtable mapping alloc_pool names to descriptors. */
+static htab_t alloc_pool_hash;
+
+/* Hashtable helpers. */
+static hashval_t
+hash_descriptor (const void *p)
+{
+ const struct alloc_pool_descriptor *const d =
+ (const struct alloc_pool_descriptor * )p;
+ return htab_hash_pointer (d->name);
+}
+static int
+eq_descriptor (const void *p1, const void *p2)
+{
+ const struct alloc_pool_descriptor *const d =
+ (const struct alloc_pool_descriptor *) p1;
+ return d->name == p2;
+}
+
+/* For given name, return descriptor, create new if needed. */
+static struct alloc_pool_descriptor *
+alloc_pool_descriptor (const char *name)
+{
+ struct alloc_pool_descriptor **slot;
+
+ if (!alloc_pool_hash)
+ alloc_pool_hash = htab_create (10, hash_descriptor, eq_descriptor, NULL);
+
+ slot = (struct alloc_pool_descriptor **)
+ htab_find_slot_with_hash (alloc_pool_hash, name,
+ htab_hash_pointer (name),
+ INSERT);
+ if (*slot)
+ return *slot;
+ *slot = XCNEW (struct alloc_pool_descriptor);
+ (*slot)->name = name;
+ return *slot;
+}
+#endif
+
/* Create a pool of things of size SIZE, with NUM in each block we
allocate. */
alloc_pool
-create_alloc_pool (name, size, num)
- const char *name;
- size_t size;
- size_t num;
+create_alloc_pool (const char *name, size_t size, size_t num)
{
alloc_pool pool;
- size_t pool_size, header_size;
+ size_t header_size;
+#ifdef GATHER_STATISTICS
+ struct alloc_pool_descriptor *desc;
+#endif
- if (!name)
- abort ();
+ gcc_assert (name);
/* Make size large enough to store the list header. */
if (size < sizeof (alloc_pool_list))
size = sizeof (alloc_pool_list);
/* Now align the size to a multiple of 4. */
- size = align_four (size);
+ size = align_eight (size);
- /* Um, we can't really allocate 0 elements per block. */
- if (num == 0)
- abort ();
+#ifdef ENABLE_CHECKING
+ /* Add the aligned size of ID. */
+ size += offsetof (allocation_object, u.data);
+#endif
- /* Find the size of the pool structure, and the name. */
- pool_size = sizeof (struct alloc_pool_def);
+ /* Um, we can't really allocate 0 elements per block. */
+ gcc_assert (num);
- /* and allocate that much memory. */
- pool = (alloc_pool) xmalloc (pool_size);
+ /* Allocate memory for the pool structure. */
+ pool = XNEW (struct alloc_pool_def);
/* Now init the various pieces of our pool structure. */
- pool->name = xstrdup (name);
+ pool->name = /*xstrdup (name)*/name;
+#ifdef GATHER_STATISTICS
+ desc = alloc_pool_descriptor (name);
+ desc->elt_size = size;
+ desc->created++;
+#endif
pool->elt_size = size;
pool->elts_per_block = num;
- /* List header size should be a multiple of 8 */
+ /* List header size should be a multiple of 8. */
header_size = align_eight (sizeof (struct alloc_pool_list_def));
pool->block_size = (size * num) + header_size;
- pool->free_list = NULL;
+ pool->returned_free_list = NULL;
+ pool->virgin_free_list = NULL;
+ pool->virgin_elts_remaining = 0;
pool->elts_allocated = 0;
pool->elts_free = 0;
pool->blocks_allocated = 0;
pool->block_list = NULL;
+#ifdef ENABLE_CHECKING
+ /* Increase the last used ID and use it for this pool.
+ ID == 0 is used for free elements of pool so skip it. */
+ last_id++;
+ if (last_id == 0)
+ last_id++;
+
+ pool->id = last_id;
+#endif
+
return (pool);
}
/* Free all memory allocated for the given memory pool. */
void
-free_alloc_pool (pool)
- alloc_pool pool;
+empty_alloc_pool (alloc_pool pool)
{
alloc_pool_list block, next_block;
+#ifdef GATHER_STATISTICS
+ struct alloc_pool_descriptor *desc = alloc_pool_descriptor (pool->name);
+#endif
- if (!pool)
- abort ();
+ gcc_assert (pool);
/* Free each block allocated to the pool. */
for (block = pool->block_list; block != NULL; block = next_block)
next_block = block->next;
free (block);
}
- /* Lastly, free the pool and the name. */
- free (pool->name);
+
+#ifdef GATHER_STATISTICS
+ desc->current -= (pool->elts_allocated - pool->elts_free) * pool->elt_size;
+#endif
+ pool->returned_free_list = NULL;
+ pool->virgin_free_list = NULL;
+ pool->virgin_elts_remaining = 0;
+ pool->elts_allocated = 0;
+ pool->elts_free = 0;
+ pool->blocks_allocated = 0;
+ pool->block_list = NULL;
+}
+
+/* Free all memory allocated for the given memory pool and the pool itself. */
+void
+free_alloc_pool (alloc_pool pool)
+{
+ /* First empty the pool. */
+ empty_alloc_pool (pool);
+#ifdef ENABLE_CHECKING
+ memset (pool, 0xaf, sizeof (*pool));
+#endif
+ /* Lastly, free the pool. */
free (pool);
}
+/* Frees the alloc_pool, if it is empty and zero *POOL in this case. */
+void
+free_alloc_pool_if_empty (alloc_pool *pool)
+{
+ if ((*pool)->elts_free == (*pool)->elts_allocated)
+ {
+ free_alloc_pool (*pool);
+ *pool = NULL;
+ }
+}
+
/* Allocates one element from the pool specified. */
void *
-pool_alloc (pool)
- alloc_pool pool;
+pool_alloc (alloc_pool pool)
{
alloc_pool_list header;
- char *block;
+#ifdef GATHER_STATISTICS
+ struct alloc_pool_descriptor *desc = alloc_pool_descriptor (pool->name);
- if (!pool)
- abort ();
+ desc->allocated += pool->elt_size;
+ desc->current += pool->elt_size;
+ if (desc->peak < desc->current)
+ desc->peak = desc->current;
+#endif
+
+ gcc_assert (pool);
/* If there are no more free elements, make some more!. */
- if (!pool->free_list)
+ if (!pool->returned_free_list)
{
- size_t i;
- alloc_pool_list block_header;
-
- /* Make the block */
- block = (char *) xmalloc (pool->block_size);
- block_header = (alloc_pool_list) block;
- block += align_eight (sizeof (struct alloc_pool_list_def));
-
- /* 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)
- {
- header = (alloc_pool_list) 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;
+ char *block;
+ if (!pool->virgin_elts_remaining)
+ {
+ 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));
+
+ /* Throw it on the block list. */
+ block_header->next = pool->block_list;
+ pool->block_list = block_header;
+
+ /* 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
+ 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->free_list;
- pool->free_list = header->next;
+ header = pool->returned_free_list;
+ pool->returned_free_list = header->next;
pool->elts_free--;
+
+#ifdef ENABLE_CHECKING
+ /* Set the ID for element. */
+ ALLOCATION_OBJECT_PTR_FROM_USER_PTR (header)->id = pool->id;
+#endif
+
return ((void *) header);
}
/* Puts PTR back on POOL's free list. */
void
-pool_free (pool, ptr)
- alloc_pool pool;
- void *ptr;
+pool_free (alloc_pool pool, void *ptr)
{
alloc_pool_list header;
+#ifdef GATHER_STATISTICS
+ struct alloc_pool_descriptor *desc = alloc_pool_descriptor (pool->name);
+#endif
+
+ gcc_assert (ptr);
+
+#ifdef ENABLE_CHECKING
+ /* Check whether the PTR was allocated from POOL. */
+ gcc_assert (pool->id == ALLOCATION_OBJECT_PTR_FROM_USER_PTR (ptr)->id);
- if (!ptr)
- abort ();
+ memset (ptr, 0xaf, pool->elt_size - offsetof (allocation_object, u.data));
+ /* Mark the element to be free. */
+ ALLOCATION_OBJECT_PTR_FROM_USER_PTR (ptr)->id = 0;
+#else
/* Check if we free more than we allocated, which is Bad (TM). */
- if (pool->elts_free + 1 > pool->elts_allocated)
- abort ();
+ gcc_assert (pool->elts_free < pool->elts_allocated);
+#endif
+
header = (alloc_pool_list) ptr;
- header->next = pool->free_list;
- pool->free_list = header;
+ header->next = pool->returned_free_list;
+ pool->returned_free_list = header;
pool->elts_free++;
+
+#ifdef GATHER_STATISTICS
+ desc->current -= pool->elt_size;
+#endif
+
+}
+/* Output per-alloc_pool statistics. */
+#ifdef GATHER_STATISTICS
+
+/* Used to accumulate statistics about alloc_pool sizes. */
+struct output_info
+{
+ unsigned long total_created;
+ unsigned long total_allocated;
+};
+
+/* Called via htab_traverse. Output alloc_pool descriptor pointed out by SLOT
+ and update statistics. */
+static int
+print_statistics (void **slot, void *b)
+{
+ struct alloc_pool_descriptor *d = (struct alloc_pool_descriptor *) *slot;
+ struct output_info *i = (struct output_info *) b;
+
+ if (d->allocated)
+ {
+ fprintf (stderr, "%-22s %6d %10lu %10lu(%10lu) %10lu(%10lu) %10lu(%10lu)\n", d->name,
+ d->elt_size, d->created, d->allocated, d->allocated / d->elt_size,
+ d->peak, d->peak / d->elt_size,
+ d->current, d->current / d->elt_size);
+ i->total_allocated += d->allocated;
+ i->total_created += d->created;
+ }
+ return 1;
+}
+#endif
+
+/* Output per-alloc_pool memory usage statistics. */
+void
+dump_alloc_pool_statistics (void)
+{
+#ifdef GATHER_STATISTICS
+ struct output_info info;
+
+ if (!alloc_pool_hash)
+ return;
+
+ fprintf (stderr, "\nAlloc-pool Kind Elt size Pools Allocated (elts) Peak (elts) Leak (elts)\n");
+ fprintf (stderr, "--------------------------------------------------------------------------------------------------------------\n");
+ info.total_created = 0;
+ info.total_allocated = 0;
+ htab_traverse (alloc_pool_hash, print_statistics, &info);
+ fprintf (stderr, "--------------------------------------------------------------------------------------------------------------\n");
+ fprintf (stderr, "%-22s %7lu %10lu\n",
+ "Total", info.total_created, info.total_allocated);
+ fprintf (stderr, "--------------------------------------------------------------------------------------------------------------\n");
+#endif
}