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Diffstat (limited to 'gcc-4.8.3/gcc/alloc-pool.c')
| -rw-r--r-- | gcc-4.8.3/gcc/alloc-pool.c | 420 |
1 files changed, 420 insertions, 0 deletions
diff --git a/gcc-4.8.3/gcc/alloc-pool.c b/gcc-4.8.3/gcc/alloc-pool.c new file mode 100644 index 000000000..1989d86aa --- /dev/null +++ b/gcc-4.8.3/gcc/alloc-pool.c @@ -0,0 +1,420 @@ +/* Functions to support a pool of allocatable objects. + Copyright (C) 1987-2013 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 3, 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 COPYING3. If not see +<http://www.gnu.org/licenses/>. */ + +#include "config.h" +#include "system.h" +#include "alloc-pool.h" +#include "hash-table.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. + We do not care about alignment for floating-point types. */ + char *align_p; + HOST_WIDEST_INT align_i; + } 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 + +/* 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; +}; + +struct alloc_pool_hasher : typed_noop_remove <alloc_pool_descriptor> +{ + typedef alloc_pool_descriptor value_type; + typedef char compare_type; + static inline hashval_t hash (const alloc_pool_descriptor *); + static inline bool equal (const value_type *, const compare_type *); +}; + +/* Hashtable mapping alloc_pool names to descriptors. */ +static hash_table <alloc_pool_hasher> alloc_pool_hash; + +/* Hashtable helpers. */ +inline hashval_t +alloc_pool_hasher::hash (const value_type *d) +{ + return htab_hash_pointer (d->name); +} + +inline bool +alloc_pool_hasher::equal (const value_type *d, + const compare_type *p2) +{ + return d->name == p2; +} + +/* For given name, return descriptor, create new if needed. */ +static struct alloc_pool_descriptor * +allocate_pool_descriptor (const char *name) +{ + struct alloc_pool_descriptor **slot; + + if (!alloc_pool_hash.is_created ()) + alloc_pool_hash.create (10); + + slot = alloc_pool_hash.find_slot_with_hash (name, + htab_hash_pointer (name), INSERT); + if (*slot) + return *slot; + *slot = XCNEW (struct alloc_pool_descriptor); + (*slot)->name = name; + return *slot; +} + +/* 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 header_size; + + gcc_checking_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_checking_assert (num); + + /* 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)*/name; + pool->elt_size = size; + pool->elts_per_block = num; + + if (GATHER_STATISTICS) + { + struct alloc_pool_descriptor *desc = allocate_pool_descriptor (name); + desc->elt_size = size; + desc->created++; + } + + /* 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->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 +empty_alloc_pool (alloc_pool pool) +{ + alloc_pool_list block, next_block; + + gcc_checking_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); + } + + if (GATHER_STATISTICS) + { + struct alloc_pool_descriptor *desc = allocate_pool_descriptor (pool->name); + desc->current -= (pool->elts_allocated - pool->elts_free) * pool->elt_size; + } + + 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 (alloc_pool pool) +{ + alloc_pool_list header; +#ifdef ENABLE_VALGRIND_CHECKING + int size; +#endif + + if (GATHER_STATISTICS) + { + struct alloc_pool_descriptor *desc = allocate_pool_descriptor (pool->name); + + desc->allocated += pool->elt_size; + desc->current += pool->elt_size; + if (desc->peak < desc->current) + desc->peak = desc->current; + } + + gcc_checking_assert (pool); +#ifdef ENABLE_VALGRIND_CHECKING + size = pool->elt_size - offsetof (allocation_object, u.data); +#endif + + /* If there are no more free elements, make some more!. */ + if (!pool->returned_free_list) + { + 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 + 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))); + 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 + VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (header, size)); + + return ((void *) header); +} + +/* Puts PTR back on POOL's free list. */ +void +pool_free (alloc_pool pool, void *ptr) +{ + alloc_pool_list header; +#if defined(ENABLE_VALGRIND_CHECKING) || defined(ENABLE_CHECKING) + int size; + size = pool->elt_size - offsetof (allocation_object, u.data); +#endif + +#ifdef ENABLE_CHECKING + gcc_assert (ptr + /* Check if we free more than we allocated, which is Bad (TM). */ + && pool->elts_free < pool->elts_allocated + /* Check whether the PTR was allocated from POOL. */ + && pool->id == ALLOCATION_OBJECT_PTR_FROM_USER_PTR (ptr)->id); + + memset (ptr, 0xaf, size); + + /* Mark the element to be free. */ + ALLOCATION_OBJECT_PTR_FROM_USER_PTR (ptr)->id = 0; +#endif + + header = (alloc_pool_list) ptr; + header->next = pool->returned_free_list; + pool->returned_free_list = header; + VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (ptr, size)); + pool->elts_free++; + + if (GATHER_STATISTICS) + { + struct alloc_pool_descriptor *desc = allocate_pool_descriptor (pool->name); + desc->current -= pool->elt_size; + } +} + +/* Output per-alloc_pool statistics. */ + +/* Used to accumulate statistics about alloc_pool sizes. */ +struct output_info +{ + unsigned long total_created; + unsigned long total_allocated; +}; + +/* Called via hash_table.traverse. Output alloc_pool descriptor pointed out by + SLOT and update statistics. */ +int +print_alloc_pool_statistics (alloc_pool_descriptor **slot, + struct output_info *i) +{ + struct alloc_pool_descriptor *d = *slot; + + 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; +} + +/* Output per-alloc_pool memory usage statistics. */ +void +dump_alloc_pool_statistics (void) +{ + struct output_info info; + + if (! GATHER_STATISTICS) + return; + + if (!alloc_pool_hash.is_created ()) + 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; + alloc_pool_hash.traverse <struct output_info *, + print_alloc_pool_statistics> (&info); + fprintf (stderr, "--------------------------------------------------------------------------------------------------------------\n"); + fprintf (stderr, "%-22s %7lu %10lu\n", + "Total", info.total_created, info.total_allocated); + fprintf (stderr, "--------------------------------------------------------------------------------------------------------------\n"); +} |