[thirdparty/gcc.git] / gcc / alloc-pool.c

/* Functions to support a pool of allocatable objects.
   Copyright (C) 1987, 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005
   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
version.

GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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, 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301, USA.  */

#include "config.h"
#include "system.h"
#include "alloc-pool.h"
#include "hashtab.h"

#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.  */
struct alloc_pool_descriptor
{
  const char *name;
  int allocated;
  int created;
  int peak;
  int current;
};

/* 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 *d = p;
  return htab_hash_pointer (d->name);
}
static int
eq_descriptor (const void *p1, const void *p2)
{
  const struct alloc_pool_descriptor *d = 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),
			      1);
  if (*slot)
    return *slot;
  *slot = xcalloc (sizeof (**slot), 1);
  (*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 (const char *name, size_t size, size_t num)
{
  alloc_pool pool;
  size_t pool_size, header_size;
#ifdef GATHER_STATISTICS
  struct alloc_pool_descriptor *desc;
#endif

  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_eight (size);

#ifdef ENABLE_CHECKING
  /* Add the aligned size of ID.  */
  size += offsetof (allocation_object, u.data);
#endif

  /* Um, we can't really allocate 0 elements per block.  */
  gcc_assert (num);

  /* Find the size of the pool structure, and the name.  */
  pool_size = sizeof (struct alloc_pool_def);

  /* and allocate that much memory.  */
  pool = xmalloc (pool_size);

  /* Now init the various pieces of our pool structure.  */
  pool->name = /*xstrdup (name)*/name;
#ifdef GATHER_STATISTICS
  desc = alloc_pool_descriptor (name);
  desc->created++;
#endif
  pool->elt_size = size;
  pool->elts_per_block = num;

  /* 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->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 (alloc_pool pool)
{
  alloc_pool_list block, next_block;
#ifdef GATHER_STATISTICS
  struct alloc_pool_descriptor *desc = alloc_pool_descriptor (pool->name);
#endif

  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);
#ifdef GATHER_STATISTICS
      desc->current -= pool->block_size;
#endif
    }
#ifdef ENABLE_CHECKING
  memset (pool, 0xaf, sizeof (*pool));
#endif
  /* Lastly, free the pool.  */
  free (pool);
}

/* 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;
    }

  /* Pull the first free element from the free list, and return it.  */
  header = pool->free_list;
  pool->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 (alloc_pool pool, void *ptr)
{
  alloc_pool_list header;

  gcc_assert (ptr);

#ifdef ENABLE_CHECKING
  memset (ptr, 0xaf, pool->elt_size - offsetof (allocation_object, u.data));

  /* Check whether the PTR was allocated from POOL.  */
  gcc_assert (pool->id == ALLOCATION_OBJECT_PTR_FROM_USER_PTR (ptr)->id);

  /* 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).  */
  gcc_assert (pool->elts_free < pool->elts_allocated);
#endif

  header = (alloc_pool_list) ptr;
  header->next = pool->free_list;
  pool->free_list = header;
  pool->elts_free++;
}
/* Output per-alloc_pool statistics.  */
#ifdef GATHER_STATISTICS

/* Used to accumulate statistics about alloc_pool sizes.  */
struct output_info
{
  int count;
  int size;
};

/* 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, "%-21s %6d %10d %10d %10d\n", d->name,
	       d->created, d->allocated, d->peak, d->current);
      i->size += d->allocated;
      i->count += 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        Pools  Allocated      Peak        Leak\n");
  fprintf (stderr, "-------------------------------------------------------------\n");
  info.count = 0;
  info.size = 0;
  htab_traverse (alloc_pool_hash, print_statistics, &info);
  fprintf (stderr, "-------------------------------------------------------------\n");
  fprintf (stderr, "%-20s %7d %10d\n",
	   "Total", info.count, info.size);
  fprintf (stderr, "-------------------------------------------------------------\n");
#endif
}
Commit	Line	Data
7f22efe1	1	/* Functions to support a pool of allocatable objects.
a2130901	2	Copyright (C) 1987, 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005
76abd4c6	3	Free Software Foundation, Inc.
7f22efe1 DB	4	Contributed by Daniel Berlin <dan@cgsoftware.com>
	5
	6	This file is part of GCC.
	7
	8	GCC is free software; you can redistribute it and/or modify it under
	9	the terms of the GNU General Public License as published by the Free
	10	Software Foundation; either version 2, or (at your option) any later
	11	version.
	12
	13	GCC is distributed in the hope that it will be useful, but WITHOUT ANY
	14	WARRANTY; without even the implied warranty of MERCHANTABILITY or
	15	FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	16	for more details.
	17
	18	You should have received a copy of the GNU General Public License
	19	along with GCC; see the file COPYING. If not, write to the Free
366ccddb KC	20	Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
366ccddb KC	21	02110-1301, USA. */
7f22efe1	22
7f22efe1 DB	23	#include "config.h"
	24	#include "system.h"
	25	#include "alloc-pool.h"
1e0f41c9	26	#include "hashtab.h"
7f22efe1	27
7f22efe1 DB	28	#define align_eight(x) (((x+7) >> 3) << 3)
7f22efe1 DB	29
76abd4c6 JZ	30	/* The internal allocation object. */
	31	typedef struct allocation_object_def
	32	{
	33	#ifdef ENABLE_CHECKING
	34	/* The ID of alloc pool which the object was allocated from. */
	35	ALLOC_POOL_ID_TYPE id;
	36	#endif
	37
	38	union
	39	{
	40	/* The data of the object. */
	41	char data[1];
	42
	43	/* Because we want any type of data to be well aligned after the ID,
	44	the following elements are here. They are never accessed so
	45	the allocated object may be even smaller than this structure. */
	46	char *align_p;
76abd4c6	47	HOST_WIDEST_INT align_i;
76abd4c6	48	long double align_ld;
76abd4c6 JZ	49	} u;
	50	} allocation_object;
	51
	52	/* Convert a pointer to allocation_object from a pointer to user data. */
	53	#define ALLOCATION_OBJECT_PTR_FROM_USER_PTR(X) \
	54	((allocation_object ) (((char ) (X)) \
	55	- offsetof (allocation_object, u.data)))
	56
	57	/* Convert a pointer to user data from a pointer to allocation_object. */
	58	#define USER_PTR_FROM_ALLOCATION_OBJECT_PTR(X) \
	59	((void ) (((allocation_object ) (X))->u.data))
	60
517958ba	61	#ifdef ENABLE_CHECKING
76abd4c6 JZ	62	/* Last used ID. */
76abd4c6 JZ	63	static ALLOC_POOL_ID_TYPE last_id;
517958ba	64	#endif
76abd4c6	65
1e0f41c9 JH	66	#ifdef GATHER_STATISTICS
1e0f41c9 JH	67
a457ee07	68	/* Store information about each particular alloc_pool. */
1e0f41c9 JH	69	struct alloc_pool_descriptor
	70	{
	71	const char *name;
	72	int allocated;
	73	int created;
	74	int peak;
	75	int current;
	76	};
	77
	78	/* Hashtable mapping alloc_pool names to descriptors. */
	79	static htab_t alloc_pool_hash;
	80
	81	/* Hashtable helpers. */
	82	static hashval_t
	83	hash_descriptor (const void *p)
	84	{
	85	const struct alloc_pool_descriptor *d = p;
	86	return htab_hash_pointer (d->name);
	87	}
	88	static int
	89	eq_descriptor (const void p1, const void p2)
	90	{
	91	const struct alloc_pool_descriptor *d = p1;
	92	return d->name == p2;
	93	}
	94
	95	/* For given name, return descriptor, create new if needed. */
	96	static struct alloc_pool_descriptor *
	97	alloc_pool_descriptor (const char *name)
	98	{
	99	struct alloc_pool_descriptor **slot;
	100
	101	if (!alloc_pool_hash)
	102	alloc_pool_hash = htab_create (10, hash_descriptor, eq_descriptor, NULL);
	103
	104	slot = (struct alloc_pool_descriptor **)
	105	htab_find_slot_with_hash (alloc_pool_hash, name,
	106	htab_hash_pointer (name),
	107	1);
	108	if (*slot)
	109	return *slot;
	110	slot = xcalloc (sizeof (*slot), 1);
	111	(*slot)->name = name;
	112	return *slot;
	113	}
	114	#endif
	115
7f22efe1 DB	116	/* Create a pool of things of size SIZE, with NUM in each block we
	117	allocate. */
	118
	119	alloc_pool
4682ae04	120	create_alloc_pool (const char *name, size_t size, size_t num)
7f22efe1 DB	121	{
	122	alloc_pool pool;
	123	size_t pool_size, header_size;
1e0f41c9 JH	124	#ifdef GATHER_STATISTICS
	125	struct alloc_pool_descriptor *desc;
	126	#endif
7f22efe1	127
298e6adc	128	gcc_assert (name);
7f22efe1 DB	129
	130	/* Make size large enough to store the list header. */
	131	if (size < sizeof (alloc_pool_list))
	132	size = sizeof (alloc_pool_list);
	133
	134	/* Now align the size to a multiple of 4. */
8b07361e	135	size = align_eight (size);
7f22efe1	136
76abd4c6 JZ	137	#ifdef ENABLE_CHECKING
	138	/* Add the aligned size of ID. */
	139	size += offsetof (allocation_object, u.data);
	140	#endif
	141
7f22efe1	142	/* Um, we can't really allocate 0 elements per block. */
298e6adc	143	gcc_assert (num);
7f22efe1 DB	144
	145	/* Find the size of the pool structure, and the name. */
	146	pool_size = sizeof (struct alloc_pool_def);
	147
	148	/* and allocate that much memory. */
703ad42b	149	pool = xmalloc (pool_size);
7f22efe1 DB	150
7f22efe1 DB	151	/* Now init the various pieces of our pool structure. */
1e0f41c9 JH	152	pool->name = /xstrdup (name)/name;
	153	#ifdef GATHER_STATISTICS
	154	desc = alloc_pool_descriptor (name);
	155	desc->created++;
	156	#endif
7f22efe1 DB	157	pool->elt_size = size;
	158	pool->elts_per_block = num;
	159
6614fd40	160	/* List header size should be a multiple of 8. */
7f22efe1 DB	161	header_size = align_eight (sizeof (struct alloc_pool_list_def));
	162
	163	pool->block_size = (size * num) + header_size;
	164	pool->free_list = NULL;
	165	pool->elts_allocated = 0;
	166	pool->elts_free = 0;
	167	pool->blocks_allocated = 0;
	168	pool->block_list = NULL;
	169
76abd4c6 JZ	170	#ifdef ENABLE_CHECKING
	171	/* Increase the last used ID and use it for this pool.
	172	ID == 0 is used for free elements of pool so skip it. */
	173	last_id++;
	174	if (last_id == 0)
	175	last_id++;
	176
	177	pool->id = last_id;
	178	#endif
	179
7f22efe1 DB	180	return (pool);
	181	}
	182
	183	/* Free all memory allocated for the given memory pool. */
	184	void
4682ae04	185	free_alloc_pool (alloc_pool pool)
7f22efe1 DB	186	{
7f22efe1 DB	187	alloc_pool_list block, next_block;
1e0f41c9 JH	188	#ifdef GATHER_STATISTICS
	189	struct alloc_pool_descriptor *desc = alloc_pool_descriptor (pool->name);
	190	#endif
7f22efe1	191
298e6adc	192	gcc_assert (pool);
7f22efe1 DB	193
	194	/* Free each block allocated to the pool. */
	195	for (block = pool->block_list; block != NULL; block = next_block)
	196	{
	197	next_block = block->next;
	198	free (block);
1e0f41c9 JH	199	#ifdef GATHER_STATISTICS
	200	desc->current -= pool->block_size;
	201	#endif
7f22efe1	202	}
8b07361e JH	203	#ifdef ENABLE_CHECKING
	204	memset (pool, 0xaf, sizeof (*pool));
	205	#endif
1e0f41c9	206	/* Lastly, free the pool. */
7f22efe1 DB	207	free (pool);
	208	}
	209
	210	/* Allocates one element from the pool specified. */
	211	void *
4682ae04	212	pool_alloc (alloc_pool pool)
7f22efe1 DB	213	{
	214	alloc_pool_list header;
	215	char *block;
1e0f41c9 JH	216	#ifdef GATHER_STATISTICS
	217	struct alloc_pool_descriptor *desc = alloc_pool_descriptor (pool->name);
	218
	219	desc->allocated+=pool->elt_size;
	220	#endif
7f22efe1	221
298e6adc	222	gcc_assert (pool);
7f22efe1 DB	223
	224	/* If there are no more free elements, make some more!. */
	225	if (!pool->free_list)
	226	{
	227	size_t i;
	228	alloc_pool_list block_header;
	229
f9da5064	230	/* Make the block. */
5ed6ace5	231	block = XNEWVEC (char, pool->block_size);
7f22efe1 DB	232	block_header = (alloc_pool_list) block;
7f22efe1 DB	233	block += align_eight (sizeof (struct alloc_pool_list_def));
1e0f41c9 JH	234	#ifdef GATHER_STATISTICS
	235	desc->current += pool->block_size;
	236	if (desc->peak < desc->current)
	237	desc->peak = desc->current;
	238	#endif
7f22efe1	239
f9da5064	240	/* Throw it on the block list. */
7f22efe1 DB	241	block_header->next = pool->block_list;
	242	pool->block_list = block_header;
	243
	244	/* Now put the actual block pieces onto the free list. */
	245	for (i = 0; i < pool->elts_per_block; i++, block += pool->elt_size)
	246	{
76abd4c6 JZ	247	#ifdef ENABLE_CHECKING
	248	/* Mark the element to be free. */
	249	((allocation_object *) block)->id = 0;
	250	#endif
	251	header = (alloc_pool_list) USER_PTR_FROM_ALLOCATION_OBJECT_PTR (block);
7f22efe1 DB	252	header->next = pool->free_list;
	253	pool->free_list = header;
	254	}
	255	/* Also update the number of elements we have free/allocated, and
	256	increment the allocated block count. */
	257	pool->elts_allocated += pool->elts_per_block;
	258	pool->elts_free += pool->elts_per_block;
	259	pool->blocks_allocated += 1;
	260	}
	261
	262	/* Pull the first free element from the free list, and return it. */
	263	header = pool->free_list;
	264	pool->free_list = header->next;
	265	pool->elts_free--;
76abd4c6 JZ	266
	267	#ifdef ENABLE_CHECKING
	268	/* Set the ID for element. */
	269	ALLOCATION_OBJECT_PTR_FROM_USER_PTR (header)->id = pool->id;
	270	#endif
	271
7f22efe1 DB	272	return ((void *) header);
	273	}
	274
	275	/* Puts PTR back on POOL's free list. */
	276	void
4682ae04	277	pool_free (alloc_pool pool, void *ptr)
7f22efe1 DB	278	{
	279	alloc_pool_list header;
	280
298e6adc	281	gcc_assert (ptr);
7f22efe1	282
298e6adc	283	#ifdef ENABLE_CHECKING
8b07361e JH	284	memset (ptr, 0xaf, pool->elt_size - offsetof (allocation_object, u.data));
8b07361e JH	285
76abd4c6	286	/* Check whether the PTR was allocated from POOL. */
298e6adc	287	gcc_assert (pool->id == ALLOCATION_OBJECT_PTR_FROM_USER_PTR (ptr)->id);
76abd4c6 JZ	288
	289	/* Mark the element to be free. */
	290	ALLOCATION_OBJECT_PTR_FROM_USER_PTR (ptr)->id = 0;
	291	#else
7f22efe1	292	/* Check if we free more than we allocated, which is Bad (TM). */
298e6adc	293	gcc_assert (pool->elts_free < pool->elts_allocated);
76abd4c6 JZ	294	#endif
76abd4c6 JZ	295
7f22efe1 DB	296	header = (alloc_pool_list) ptr;
	297	header->next = pool->free_list;
	298	pool->free_list = header;
	299	pool->elts_free++;
	300	}
1e0f41c9 JH	301	/* Output per-alloc_pool statistics. */
	302	#ifdef GATHER_STATISTICS
	303
	304	/* Used to accumulate statistics about alloc_pool sizes. */
	305	struct output_info
	306	{
	307	int count;
	308	int size;
	309	};
	310
	311	/* Called via htab_traverse. Output alloc_pool descriptor pointed out by SLOT
	312	and update statistics. */
	313	static int
	314	print_statistics (void *slot, void b)
	315	{
	316	struct alloc_pool_descriptor d = (struct alloc_pool_descriptor ) *slot;
	317	struct output_info i = (struct output_info ) b;
	318
	319	if (d->allocated)
	320	{
	321	fprintf (stderr, "%-21s %6d %10d %10d %10d\n", d->name,
	322	d->created, d->allocated, d->peak, d->current);
	323	i->size += d->allocated;
	324	i->count += d->created;
	325	}
	326	return 1;
	327	}
	328	#endif
	329
	330	/* Output per-alloc_pool memory usage statistics. */
	331	void dump_alloc_pool_statistics (void)
	332	{
	333	#ifdef GATHER_STATISTICS
	334	struct output_info info;
	335
08cee789 DJ	336	if (!alloc_pool_hash)
	337	return;
	338
1e0f41c9 JH	339	fprintf (stderr, "\nAlloc-pool Kind Pools Allocated Peak Leak\n");
	340	fprintf (stderr, "-------------------------------------------------------------\n");
	341	info.count = 0;
	342	info.size = 0;
	343	htab_traverse (alloc_pool_hash, print_statistics, &info);
	344	fprintf (stderr, "-------------------------------------------------------------\n");
	345	fprintf (stderr, "%-20s %7d %10d\n",
	346	"Total", info.count, info.size);
	347	fprintf (stderr, "-------------------------------------------------------------\n");
	348	#endif
	349	}