2009-01-26 Andrew Stubbs <ams@codesourcery.com>

[deliverable/binutils-gdb.git] / gas / hash.c

diff --git a/gas/hash.c b/gas/hash.c
index 2756f23f6c5184170025ae70122c26f7df8fd4fc..06fadcbf4d762487c9e5c6ca0fd12776c2fec380 100644 (file)
--- a/gas/hash.c
+++ b/gas/hash.c
@@ -1,13 +1,13 @@
 /* hash.c -- gas hash table code
    Copyright 1987, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999,
 /* hash.c -- gas hash table code
    Copyright 1987, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999,

-   2000, 2001, 2002
+   2000, 2001, 2002, 2003, 2005, 2007, 2008

    Free Software Foundation, Inc.
 
    This file is part of GAS, the GNU Assembler.
 
    GAS is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    Free Software Foundation, Inc.
 
    This file is part of GAS, the GNU Assembler.
 
    GAS 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)
+   the Free Software Foundation; either version 3, or (at your option)

    any later version.
 
    GAS is distributed in the hope that it will be useful,
    any later version.
 
    GAS is distributed in the hope that it will be useful,


@@ -17,13 +17,13 @@
 
    You should have received a copy of the GNU General Public License
    along with GAS; see the file COPYING.  If not, write to the Free
 
    You should have received a copy of the GNU General Public License
    along with GAS; see the file COPYING.  If not, write to the Free

-   Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-   02111-1307, USA.  */
+   Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
+   02110-1301, USA.  */

 
 /* This version of the hash table code is a wholescale replacement of
    the old hash table code, which was fairly bad.  This is based on
    the hash table code in BFD, but optimized slightly for the
 
 /* This version of the hash table code is a wholescale replacement of
    the old hash table code, which was fairly bad.  This is based on
    the hash table code in BFD, but optimized slightly for the

-   asssembler.  The assembler does not need to derive structures that
+   assembler.  The assembler does not need to derive structures that

    are stored in the hash table.  Instead, it always stores a pointer.
    The assembler uses the hash table mostly to store symbols, and we
    don't need to confuse the symbol structure with a hash table
    are stored in the hash table.  Instead, it always stores a pointer.
    The assembler uses the hash table mostly to store symbols, and we
    don't need to confuse the symbol structure with a hash table


@@ -33,10 +33,6 @@
 #include "safe-ctype.h"
 #include "obstack.h"
 
 #include "safe-ctype.h"
 #include "obstack.h"
 

-/* The default number of entries to use when creating a hash table.  */
-
-#define DEFAULT_SIZE (4051)
-

 /* An entry in a hash table.  */
 
 struct hash_entry {
 /* An entry in a hash table.  */
 
 struct hash_entry {


@@ -48,7 +44,7 @@ struct hash_entry {
      table.  */
   unsigned long hash;
   /* Pointer being stored in the hash table.  */
      table.  */
   unsigned long hash;
   /* Pointer being stored in the hash table.  */

-  PTR data;
+  void *data;

 };
 
 /* A hash table.  */
 };
 
 /* A hash table.  */


@@ -72,21 +68,55 @@ struct hash_control {
 #endif /* HASH_STATISTICS */
 };
 
 #endif /* HASH_STATISTICS */
 };
 

+/* The default number of entries to use when creating a hash table.
+   Note this value can be reduced to 4051 by using the command line
+   switch --reduce-memory-overheads, or set to other values by using
+   the --hash-size=<NUMBER> switch.  */
+
+static unsigned long gas_hash_table_size = 65537;
+
+void
+set_gas_hash_table_size (unsigned long size)
+{
+  gas_hash_table_size = size;
+}
+
+/* FIXME: This function should be amalgmated with bfd/hash.c:bfd_hash_set_default_size().  */
+static unsigned long
+get_gas_hash_table_size (void)
+{
+  /* Extend this prime list if you want more granularity of hash table size.  */
+  static const unsigned long hash_size_primes[] =
+    {
+      1021, 4051, 8599, 16699, 65537
+    };
+  unsigned int index;
+
+  /* Work out the best prime number near the hash_size.
+     FIXME: This could be a more sophisticated algorithm,
+     but is it really worth implementing it ?   */
+  for (index = 0; index < ARRAY_SIZE (hash_size_primes) - 1; ++index)
+    if (gas_hash_table_size <= hash_size_primes[index])
+      break;
+
+  return hash_size_primes[index];
+}
+

 /* Create a hash table.  This return a control block.  */
 
 struct hash_control *
 /* Create a hash table.  This return a control block.  */
 
 struct hash_control *

-hash_new ()
+hash_new (void)

 {
 {

-  unsigned int size;
+  unsigned long size;
+  unsigned long alloc;

   struct hash_control *ret;
   struct hash_control *ret;

-  unsigned int alloc;

 
 

-  size = DEFAULT_SIZE;
+  size = get_gas_hash_table_size ();

 
 

-  ret = (struct hash_control *) xmalloc (sizeof *ret);
+  ret = xmalloc (sizeof *ret);

   obstack_begin (&ret->memory, chunksize);
   alloc = size * sizeof (struct hash_entry *);
   obstack_begin (&ret->memory, chunksize);
   alloc = size * sizeof (struct hash_entry *);

-  ret->table = (struct hash_entry **) obstack_alloc (&ret->memory, alloc);
+  ret->table = obstack_alloc (&ret->memory, alloc);

   memset (ret->table, 0, alloc);
   ret->size = size;
 
   memset (ret->table, 0, alloc);
   ret->size = size;
 


@@ -105,8 +135,7 @@ hash_new ()
 /* Delete a hash table, freeing all allocated memory.  */
 
 void
 /* Delete a hash table, freeing all allocated memory.  */
 
 void

-hash_die (table)
-     struct hash_control *table;
+hash_die (struct hash_control *table)

 {
   obstack_free (&table->memory, 0);
   free (table);
 {
   obstack_free (&table->memory, 0);
   free (table);


@@ -121,22 +150,13 @@ hash_die (table)
    Each time we look up a string, we move it to the start of the list
    for its hash code, to take advantage of referential locality.  */
 
    Each time we look up a string, we move it to the start of the list
    for its hash code, to take advantage of referential locality.  */
 

-static struct hash_entry *hash_lookup PARAMS ((struct hash_control *,
-                                              const char *,
-                                              struct hash_entry ***,
-                                              unsigned long *));
-

 static struct hash_entry *
 static struct hash_entry *

-hash_lookup (table, key, plist, phash)
-     struct hash_control *table;
-     const char *key;
-     struct hash_entry ***plist;
-     unsigned long *phash;
+hash_lookup (struct hash_control *table, const char *key, size_t len,
+            struct hash_entry ***plist, unsigned long *phash)

 {
 {

-  register unsigned long hash;
-  unsigned int len;
-  register const unsigned char *s;
-  register unsigned int c;
+  unsigned long hash;
+  size_t n;
+  unsigned int c;

   unsigned int index;
   struct hash_entry **list;
   struct hash_entry *p;
   unsigned int index;
   struct hash_entry **list;
   struct hash_entry *p;


@@ -147,13 +167,11 @@ hash_lookup (table, key, plist, phash)
 #endif
 
   hash = 0;
 #endif
 
   hash = 0;

-  len = 0;
-  s = (const unsigned char *) key;
-  while ((c = *s++) != '\0')
+  for (n = 0; n < len; n++)

     {
     {

+      c = key[n];

       hash += c + (c << 17);
       hash ^= hash >> 2;
       hash += c + (c << 17);
       hash ^= hash >> 2;

-      ++len;

     }
   hash += len + (len << 17);
   hash ^= hash >> 2;
     }
   hash += len + (len << 17);
   hash ^= hash >> 2;


@@ -180,7 +198,7 @@ hash_lookup (table, key, plist, phash)
          ++table->string_compares;
 #endif
 
          ++table->string_compares;
 #endif
 

-         if (strcmp (p->string, key) == 0)
+         if (strncmp (p->string, key, len) == 0 && p->string[len] == '\0')

            {
              if (prev != NULL)
                {
            {
              if (prev != NULL)
                {


@@ -205,16 +223,13 @@ hash_lookup (table, key, plist, phash)
    hash table.  */
 
 const char *
    hash table.  */
 
 const char *

-hash_insert (table, key, value)
-     struct hash_control *table;
-     const char *key;
-     PTR value;
+hash_insert (struct hash_control *table, const char *key, void *value)

 {
   struct hash_entry *p;
   struct hash_entry **list;
   unsigned long hash;
 
 {
   struct hash_entry *p;
   struct hash_entry **list;
   unsigned long hash;
 

-  p = hash_lookup (table, key, &list, &hash);
+  p = hash_lookup (table, key, strlen (key), &list, &hash);

   if (p != NULL)
     return "exists";
 
   if (p != NULL)
     return "exists";
 


@@ -222,7 +237,7 @@ hash_insert (table, key, value)
   ++table->insertions;
 #endif
 
   ++table->insertions;
 #endif
 

-  p = (struct hash_entry *) obstack_alloc (&table->memory, sizeof (*p));
+  p = obstack_alloc (&table->memory, sizeof (*p));

   p->string = key;
   p->hash = hash;
   p->data = value;
   p->string = key;
   p->hash = hash;
   p->data = value;


@@ -238,16 +253,13 @@ hash_insert (table, key, value)
    error.  If an entry already exists, its value is replaced.  */
 
 const char *
    error.  If an entry already exists, its value is replaced.  */
 
 const char *

-hash_jam (table, key, value)
-     struct hash_control *table;
-     const char *key;
-     PTR value;
+hash_jam (struct hash_control *table, const char *key, void *value)

 {
   struct hash_entry *p;
   struct hash_entry **list;
   unsigned long hash;
 
 {
   struct hash_entry *p;
   struct hash_entry **list;
   unsigned long hash;
 

-  p = hash_lookup (table, key, &list, &hash);
+  p = hash_lookup (table, key, strlen (key), &list, &hash);

   if (p != NULL)
     {
 #ifdef HASH_STATISTICS
   if (p != NULL)
     {
 #ifdef HASH_STATISTICS


@@ -262,7 +274,7 @@ hash_jam (table, key, value)
       ++table->insertions;
 #endif
 
       ++table->insertions;
 #endif
 

-      p = (struct hash_entry *) obstack_alloc (&table->memory, sizeof (*p));
+      p = obstack_alloc (&table->memory, sizeof (*p));

       p->string = key;
       p->hash = hash;
       p->data = value;
       p->string = key;
       p->hash = hash;
       p->data = value;


@@ -278,16 +290,13 @@ hash_jam (table, key, value)
    value stored for the entry.  If the entry is not found in the hash
    table, this does nothing and returns NULL.  */
 
    value stored for the entry.  If the entry is not found in the hash
    table, this does nothing and returns NULL.  */
 

-PTR
-hash_replace (table, key, value)
-     struct hash_control *table;
-     const char *key;
-     PTR value;
+void *
+hash_replace (struct hash_control *table, const char *key, void *value)

 {
   struct hash_entry *p;
 {
   struct hash_entry *p;

-  PTR ret;
+  void *ret;

 
 

-  p = hash_lookup (table, key, NULL, NULL);
+  p = hash_lookup (table, key, strlen (key), NULL, NULL);

   if (p == NULL)
     return NULL;
 
   if (p == NULL)
     return NULL;
 


@@ -305,14 +314,27 @@ hash_replace (table, key, value)
 /* Find an entry in a hash table, returning its value.  Returns NULL
    if the entry is not found.  */
 
 /* Find an entry in a hash table, returning its value.  Returns NULL
    if the entry is not found.  */
 

-PTR
-hash_find (table, key)
-     struct hash_control *table;
-     const char *key;
+void *
+hash_find (struct hash_control *table, const char *key)
+{
+  struct hash_entry *p;
+
+  p = hash_lookup (table, key, strlen (key), NULL, NULL);
+  if (p == NULL)
+    return NULL;
+
+  return p->data;
+}
+
+/* As hash_find, but KEY is of length LEN and is not guaranteed to be
+   NUL-terminated.  */
+
+void *
+hash_find_n (struct hash_control *table, const char *key, size_t len)

 {
   struct hash_entry *p;
 
 {
   struct hash_entry *p;
 

-  p = hash_lookup (table, key, NULL, NULL);
+  p = hash_lookup (table, key, len, NULL, NULL);

   if (p == NULL)
     return NULL;
 
   if (p == NULL)
     return NULL;
 


@@ -322,15 +344,13 @@ hash_find (table, key)
 /* Delete an entry from a hash table.  This returns the value stored
    for that entry, or NULL if there is no such entry.  */
 
 /* Delete an entry from a hash table.  This returns the value stored
    for that entry, or NULL if there is no such entry.  */
 

-PTR
-hash_delete (table, key)
-     struct hash_control *table;
-     const char *key;
+void *
+hash_delete (struct hash_control *table, const char *key, int freeme)

 {
   struct hash_entry *p;
   struct hash_entry **list;
 
 {
   struct hash_entry *p;
   struct hash_entry **list;
 

-  p = hash_lookup (table, key, &list, NULL);
+  p = hash_lookup (table, key, strlen (key), &list, NULL);

   if (p == NULL)
     return NULL;
 
   if (p == NULL)
     return NULL;
 


@@ -343,9 +363,8 @@ hash_delete (table, key)
 
   *list = p->next;
 
 
   *list = p->next;
 

-  /* Note that we never reclaim the memory for this entry.  If gas
-     ever starts deleting hash table entries in a big way, this will
-     have to change.  */
+  if (freeme)
+    obstack_free (&table->memory, p);

 
   return p->data;
 }
 
   return p->data;
 }


@@ -354,9 +373,8 @@ hash_delete (table, key)
    hash table.  */
 
 void
    hash table.  */
 
 void

-hash_traverse (table, pfn)
-     struct hash_control *table;
-     void (*pfn) PARAMS ((const char *key, PTR value));
+hash_traverse (struct hash_control *table,
+              void (*pfn) (const char *key, void *value))

 {
   unsigned int i;
 
 {
   unsigned int i;
 


@@ -373,10 +391,9 @@ hash_traverse (table, pfn)
    name of the hash table, used for printing a header.  */
 
 void
    name of the hash table, used for printing a header.  */
 
 void

-hash_print_statistics (f, name, table)
-     FILE *f ATTRIBUTE_UNUSED;
-     const char *name ATTRIBUTE_UNUSED;
-     struct hash_control *table ATTRIBUTE_UNUSED;
+hash_print_statistics (FILE *f ATTRIBUTE_UNUSED,
+                      const char *name ATTRIBUTE_UNUSED,
+                      struct hash_control *table ATTRIBUTE_UNUSED)

 {
 #ifdef HASH_STATISTICS
   unsigned int i;
 {
 #ifdef HASH_STATISTICS
   unsigned int i;