Written by Fred Fish <fnf@cygnus.com>
Rewritten by Jim Blandy <jimb@cygnus.com>
- Copyright (C) 1999, 2000, 2002, 2003, 2007, 2008
+ Copyright (C) 1999, 2000, 2002, 2003, 2007, 2008, 2009, 2010
Free Software Foundation, Inc.
This file is part of GDB.
unsigned long
hash(const void *addr, int length)
{
- const unsigned char *k, *e;
- unsigned long h;
-
- k = (const unsigned char *)addr;
- e = k+length;
- for (h=0; k< e;++k)
- {
- h *=16777619;
- h ^= *k;
- }
- return (h);
+ const unsigned char *k, *e;
+ unsigned long h;
+
+ k = (const unsigned char *)addr;
+ e = k+length;
+ for (h=0; k< e;++k)
+ {
+ h *=16777619;
+ h ^= *k;
+ }
+ return (h);
}
\f
/* Growing the bcache's hash table. */
/* Allocate the new table. */
{
size_t new_size = new_num_buckets * sizeof (new_buckets[0]);
+
new_buckets = (struct bstring **) xmalloc (new_size);
memset (new_buckets, 0, new_size);
/* Find a copy of the LENGTH bytes at ADDR in BCACHE. If BCACHE has
never seen those bytes before, add a copy of them to BCACHE. In
either case, return a pointer to BCACHE's copy of that string. */
-static void *
-bcache_data (const void *addr, int length, struct bcache *bcache)
+const void *
+bcache (const void *addr, int length, struct bcache *bcache)
+{
+ return bcache_full (addr, length, bcache, NULL);
+}
+
+/* Find a copy of the LENGTH bytes at ADDR in BCACHE. If BCACHE has
+ never seen those bytes before, add a copy of them to BCACHE. In
+ either case, return a pointer to BCACHE's copy of that string. If
+ optional ADDED is not NULL, return 1 in case of new entry or 0 if
+ returning an old entry. */
+
+const void *
+bcache_full (const void *addr, int length, struct bcache *bcache, int *added)
{
unsigned long full_hash;
unsigned short half_hash;
int hash_index;
struct bstring *s;
+ if (added)
+ *added = 0;
+
+ /* Lazily initialize the obstack. This can save quite a bit of
+ memory in some cases. */
+ if (bcache->total_count == 0)
+ {
+ /* We could use obstack_specify_allocation here instead, but
+ gdb_obstack.h specifies the allocation/deallocation
+ functions. */
+ obstack_init (&bcache->cache);
+ }
+
/* If our average chain length is too high, expand the hash table. */
if (bcache->unique_count >= bcache->num_buckets * CHAIN_LENGTH_THRESHOLD)
expand_hash_table (bcache);
{
struct bstring *new
= obstack_alloc (&bcache->cache, BSTRING_SIZE (length));
+
memcpy (&new->d.data, addr, length);
new->length = length;
new->next = bcache->bucket[hash_index];
bcache->unique_size += length;
bcache->structure_size += BSTRING_SIZE (length);
+ if (added)
+ *added = 1;
+
return &new->d.data;
}
}
-
-void *
-deprecated_bcache (const void *addr, int length, struct bcache *bcache)
-{
- return bcache_data (addr, length, bcache);
-}
-
-const void *
-bcache (const void *addr, int length, struct bcache *bcache)
-{
- return bcache_data (addr, length, bcache);
-}
\f
/* Allocating and freeing bcaches. */
{
/* Allocate the bcache pre-zeroed. */
struct bcache *b = XCALLOC (1, struct bcache);
- /* We could use obstack_specify_allocation here instead, but
- gdb_obstack.h specifies the allocation/deallocation
- functions. */
- obstack_init (&b->cache);
+
return b;
}
{
if (bcache == NULL)
return;
- obstack_free (&bcache->cache, 0);
+ /* Only free the obstack if we actually initialized it. */
+ if (bcache->total_count > 0)
+ obstack_free (&bcache->cache, 0);
xfree (bcache->bucket);
xfree (bcache);
}
\f
/* Printing statistics. */
-static int
-compare_ints (const void *ap, const void *bp)
-{
- /* Because we know we're comparing two ints which are positive,
- there's no danger of overflow here. */
- return * (int *) ap - * (int *) bp;
-}
-
-
static void
print_percentage (int portion, int total)
{
/* To compute the median, we need the set of chain lengths sorted. */
qsort (chain_length, c->num_buckets, sizeof (chain_length[0]),
- compare_ints);
+ compare_positive_ints);
qsort (entry_size, c->unique_count, sizeof (entry_size[0]),
- compare_ints);
+ compare_positive_ints);
if (c->num_buckets > 0)
{
int
bcache_memory_used (struct bcache *bcache)
{
+ if (bcache->total_count == 0)
+ return 0;
return obstack_memory_used (&bcache->cache);
}