/* String pool for GCC.
- Copyright (C) 2000, 2001 Free Software Foundation, Inc.
+ Copyright (C) 2000-2015 Free Software Foundation, Inc.
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/>. */
-/* String text, identifier text and identifier node allocator. Strings
- allocated by ggc_alloc_string are stored in an obstack which is
- never shrunk. Identifiers are uniquely stored in a hash table.
+/* String text, identifier text and identifier node allocator.
+ Identifiers are uniquely stored in a hash table.
- We have our own private hash table implementation. libiberty's
+ We use cpplib's hash table implementation. libiberty's
hashtab.c is not used because it requires 100% average space
overhead per string, which is unacceptable. Also, this algorithm
is faster. */
#include "config.h"
#include "system.h"
-#include "ggc.h"
+#include "coretypes.h"
+#include "ggc-internal.h"
+#include "alias.h"
+#include "symtab.h"
+#include "options.h"
#include "tree.h"
-#include "hashtable.h"
+#include "cpplib.h"
/* The "" allocated string. */
const char empty_string[] = "";
/* Character strings, each containing a single decimal digit.
Written this way to save space. */
-const char digit_vector[] = {
+static const char digit_vector[] = {
'0', 0, '1', 0, '2', 0, '3', 0, '4', 0,
'5', 0, '6', 0, '7', 0, '8', 0, '9', 0
};
+#define digit_string(d) (digit_vector + ((d) * 2))
+
struct ht *ident_hash;
-static struct obstack string_stack;
-static hashnode alloc_node PARAMS ((hash_table *));
-static int mark_ident PARAMS ((struct cpp_reader *, hashnode, const PTR));
-static void mark_ident_hash PARAMS ((void *));
+static hashnode alloc_node (cpp_hash_table *);
+static int mark_ident (struct cpp_reader *, hashnode, const void *);
+
+static void *
+stringpool_ggc_alloc (size_t x)
+{
+ return ggc_alloc_atomic (x);
+}
/* Initialize the string pool. */
void
-init_stringpool ()
+init_stringpool (void)
{
+ /* Clean up if we're called more than once.
+ (We can't make this idempotent since identifiers contain state) */
+ if (ident_hash)
+ ht_destroy (ident_hash);
+
/* Create with 16K (2^14) entries. */
ident_hash = ht_create (14);
ident_hash->alloc_node = alloc_node;
- gcc_obstack_init (&string_stack);
- ggc_add_root (&ident_hash, 1, sizeof ident_hash, mark_ident_hash);
+ ident_hash->alloc_subobject = stringpool_ggc_alloc;
}
/* Allocate a hash node. */
static hashnode
-alloc_node (table)
- hash_table *table ATTRIBUTE_UNUSED;
+alloc_node (cpp_hash_table *table ATTRIBUTE_UNUSED)
{
return GCC_IDENT_TO_HT_IDENT (make_node (IDENTIFIER_NODE));
}
/* Allocate and return a string constant of length LENGTH, containing
CONTENTS. If LENGTH is -1, CONTENTS is assumed to be a
- nul-terminated string, and the length is calculated using strlen.
- If the same string constant has been allocated before, that copy is
- returned this time too. */
+ nul-terminated string, and the length is calculated using strlen. */
const char *
-ggc_alloc_string (contents, length)
- const char *contents;
- int length;
+ggc_alloc_string (const char *contents, int length MEM_STAT_DECL)
{
+ char *result;
+
if (length == -1)
length = strlen (contents);
if (length == 1 && ISDIGIT (contents[0]))
return digit_string (contents[0] - '0');
- obstack_grow0 (&string_stack, contents, length);
- return obstack_finish (&string_stack);
+ result = (char *) ggc_internal_cleared_alloc (length + 1 PASS_MEM_STAT);
+ memcpy (result, contents, length);
+ result[length] = '\0';
+ return (const char *) result;
}
/* Return an IDENTIFIER_NODE whose name is TEXT (a null-terminated string).
If an identifier with that name has previously been referred to,
the same node is returned this time. */
+#undef get_identifier
+
tree
-get_identifier (text)
- const char *text;
+get_identifier (const char *text)
{
hashnode ht_node = ht_lookup (ident_hash,
(const unsigned char *) text,
known. */
tree
-get_identifier_with_length (text, length)
- const char *text;
- unsigned int length;
+get_identifier_with_length (const char *text, size_t length)
{
hashnode ht_node = ht_lookup (ident_hash,
(const unsigned char *) text,
NULL_TREE. */
tree
-maybe_get_identifier (text)
- const char *text;
+maybe_get_identifier (const char *text)
{
hashnode ht_node;
/* Report some basic statistics about the string pool. */
void
-stringpool_statistics ()
+stringpool_statistics (void)
{
ht_dump_statistics (ident_hash);
}
-
+\f
/* Mark an identifier for GC. */
static int
-mark_ident (pfile, h, v)
- struct cpp_reader *pfile ATTRIBUTE_UNUSED;
- hashnode h;
- const PTR v ATTRIBUTE_UNUSED;
+mark_ident (struct cpp_reader *pfile ATTRIBUTE_UNUSED, hashnode h,
+ const void *v ATTRIBUTE_UNUSED)
{
- ggc_mark_tree (HT_IDENT_TO_GCC_IDENT (h));
+ gt_ggc_m_9tree_node (HT_IDENT_TO_GCC_IDENT (h));
return 1;
}
-/* Mark all identifiers for GC. */
+/* Return true if an identifier should be removed from the table. */
-static void
-mark_ident_hash (arg)
- PTR arg ATTRIBUTE_UNUSED;
+static int
+maybe_delete_ident (struct cpp_reader *pfile ATTRIBUTE_UNUSED, hashnode h,
+ const void *v ATTRIBUTE_UNUSED)
+{
+ return !ggc_marked_p (HT_IDENT_TO_GCC_IDENT (h));
+}
+
+/* Mark the trees hanging off the identifier node for GGC. These are
+ handled specially (not using gengtype) because identifiers are only
+ roots during one part of compilation. */
+
+void
+ggc_mark_stringpool (void)
{
ht_forall (ident_hash, mark_ident, NULL);
}
+
+/* Purge the identifier hash of identifiers which are no longer
+ referenced. */
+
+void
+ggc_purge_stringpool (void)
+{
+ ht_purge (ident_hash, maybe_delete_ident, NULL);
+}
+
+/* Pointer-walking routine for strings (not very interesting, since
+ strings don't contain pointers). */
+
+void
+gt_pch_p_S (void *obj ATTRIBUTE_UNUSED, void *x ATTRIBUTE_UNUSED,
+ gt_pointer_operator op ATTRIBUTE_UNUSED,
+ void *cookie ATTRIBUTE_UNUSED)
+{
+}
+
+/* PCH pointer-walking routine for strings. */
+
+void
+gt_pch_n_S (const void *x)
+{
+ gt_pch_note_object (CONST_CAST (void *, x), CONST_CAST (void *, x),
+ >_pch_p_S);
+}
+
+
+/* User-callable entry point for marking string X. */
+
+void
+gt_pch_nx (const char *& x)
+{
+ gt_pch_n_S (x);
+}
+
+void
+gt_pch_nx (unsigned char *& x)
+{
+ gt_pch_n_S (x);
+}
+
+void
+gt_pch_nx (unsigned char& x ATTRIBUTE_UNUSED)
+{
+}
+
+void
+gt_pch_nx (unsigned char *x, gt_pointer_operator op, void *cookie)
+{
+ op (x, cookie);
+}
+\f
+/* Handle saving and restoring the string pool for PCH. */
+
+/* SPD is saved in the PCH file and holds the information needed
+ to restore the string pool. */
+
+struct GTY(()) string_pool_data {
+ ht_identifier_ptr *
+ GTY((length ("%h.nslots"),
+ nested_ptr (union tree_node, "%h ? GCC_IDENT_TO_HT_IDENT (%h) : NULL",
+ "%h ? HT_IDENT_TO_GCC_IDENT (%h) : NULL")))
+ entries;
+ unsigned int nslots;
+ unsigned int nelements;
+};
+
+static GTY(()) struct string_pool_data * spd;
+
+/* Save the stringpool data in SPD. */
+
+void
+gt_pch_save_stringpool (void)
+{
+ spd = ggc_alloc<string_pool_data> ();
+ spd->nslots = ident_hash->nslots;
+ spd->nelements = ident_hash->nelements;
+ spd->entries = ggc_vec_alloc<ht_identifier_ptr> (spd->nslots);
+ memcpy (spd->entries, ident_hash->entries,
+ spd->nslots * sizeof (spd->entries[0]));
+}
+
+/* Return the stringpool to its state before gt_pch_save_stringpool
+ was called. */
+
+void
+gt_pch_fixup_stringpool (void)
+{
+}
+
+/* A PCH file has been restored, which loaded SPD; fill the real hash table
+ from SPD. */
+
+void
+gt_pch_restore_stringpool (void)
+{
+ ht_load (ident_hash, spd->entries, spd->nslots, spd->nelements, false);
+ spd = NULL;
+}
+
+#include "gt-stringpool.h"