/* 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 GNU CC.
+This file is part of GCC.
-GNU CC 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 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.
-GNU CC is distributed in the hope that it will be useful, but WITHOUT
-ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+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 GNU CC; 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, identifer 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 "flags.h"
-#include "toplev.h"
-
-#define IS_FE_IDENT(NODE) (TREE_CODE (NODE) == IDENTIFIER_NODE)
+#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 int do_identifier_warnings;
-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 int scan_for_clashes PARAMS ((struct cpp_reader *, hashnode,
- const char *));
+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 == 0)
return empty_string;
- if (length == 1 && contents[0] >= '0' && contents[0] <= '9')
+ 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;
}
-/* NODE is an identifier known to the preprocessor. Make it known to
- the front ends as well. */
+/* 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. */
-void
-make_identifier (node)
- tree node;
+#undef get_identifier
+
+tree
+get_identifier (const char *text)
{
- /* If this identifier is longer than the clash-warning length,
- do a brute force search of the entire table for clashes. */
- if (warn_id_clash && do_identifier_warnings
- && IDENTIFIER_LENGTH (node) >= id_clash_len)
- ht_forall (ident_hash, (ht_cb) scan_for_clashes,
- IDENTIFIER_POINTER (node));
+ hashnode ht_node = ht_lookup (ident_hash,
+ (const unsigned char *) text,
+ strlen (text), HT_ALLOC);
- TREE_SET_CODE (node, IDENTIFIER_NODE);
-#ifdef GATHER_STATISTICS
- id_string_size += IDENTIFIER_LENGTH (node);
-#endif
+ /* ht_node can't be NULL here. */
+ return HT_IDENT_TO_GCC_IDENT (ht_node);
}
-/* 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. */
+/* Identical to get_identifier, except that the length is assumed
+ known. */
tree
-get_identifier (text)
- const char *text;
+get_identifier_with_length (const char *text, size_t length)
{
hashnode ht_node = ht_lookup (ident_hash,
(const unsigned char *) text,
- strlen (text), HT_ALLOC);
+ length, HT_ALLOC);
/* ht_node can't be NULL here. */
return HT_IDENT_TO_GCC_IDENT (ht_node);
NULL_TREE. */
tree
-maybe_get_identifier (text)
- const char *text;
+maybe_get_identifier (const char *text)
{
hashnode ht_node;
- tree node;
- size_t length = strlen (text);
ht_node = ht_lookup (ident_hash, (const unsigned char *) text,
- length, HT_NO_INSERT);
+ strlen (text), HT_NO_INSERT);
if (ht_node)
- {
- node = HT_IDENT_TO_GCC_IDENT (ht_node);
- if (IS_FE_IDENT (node))
- return node;
- }
+ return HT_IDENT_TO_GCC_IDENT (ht_node);
return NULL_TREE;
}
-/* If this identifier is longer than the clash-warning length,
- do a brute force search of the entire table for clashes. */
+/* Report some basic statistics about the string pool. */
-static int
-scan_for_clashes (pfile, h, text)
- struct cpp_reader *pfile ATTRIBUTE_UNUSED;
- hashnode h;
- const char *text;
-{
- tree node = HT_IDENT_TO_GCC_IDENT (h);
-
- if (IS_FE_IDENT (node)
- && IDENTIFIER_LENGTH (node) >= id_clash_len
- && !memcmp (IDENTIFIER_POINTER (node), text, id_clash_len))
- {
- warning ("\"%s\" and \"%s\" identical in first %d characters",
- text, IDENTIFIER_POINTER (node), id_clash_len);
- return 0;
- }
+void
+stringpool_statistics (void)
+{
+ ht_dump_statistics (ident_hash);
+}
+\f
+/* Mark an identifier for GC. */
+static int
+mark_ident (struct cpp_reader *pfile ATTRIBUTE_UNUSED, hashnode h,
+ const void *v ATTRIBUTE_UNUSED)
+{
+ gt_ggc_m_9tree_node (HT_IDENT_TO_GCC_IDENT (h));
return 1;
}
-/* Record the size of an identifier node for the language in use.
- SIZE is the total size in bytes.
- This is called by the language-specific files. This must be
- called before allocating any identifiers. */
+/* Return true if an identifier should be removed from the table. */
+
+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
-set_identifier_size (size)
- int size;
+ggc_mark_stringpool (void)
{
- tree_code_length[(int) IDENTIFIER_NODE]
- = (size - sizeof (struct tree_common)) / sizeof (tree);
+ ht_forall (ident_hash, mark_ident, NULL);
}
-/* Enable warnings on similar identifiers (if requested).
- Done after the built-in identifiers are created. */
+/* Purge the identifier hash of identifiers which are no longer
+ referenced. */
void
-start_identifier_warnings ()
+ggc_purge_stringpool (void)
{
- do_identifier_warnings = 1;
+ ht_purge (ident_hash, maybe_delete_ident, NULL);
}
-/* Report some basic statistics about the string pool. */
+/* Pointer-walking routine for strings (not very interesting, since
+ strings don't contain pointers). */
void
-stringpool_statistics ()
+gt_pch_p_S (void *obj ATTRIBUTE_UNUSED, void *x ATTRIBUTE_UNUSED,
+ gt_pointer_operator op ATTRIBUTE_UNUSED,
+ void *cookie ATTRIBUTE_UNUSED)
{
- ht_dump_statistics (ident_hash);
}
-/* Mark an identifier for GC. */
+/* PCH pointer-walking routine for strings. */
-static int
-mark_ident (pfile, h, v)
- struct cpp_reader *pfile ATTRIBUTE_UNUSED;
- hashnode h;
- const PTR v ATTRIBUTE_UNUSED;
+void
+gt_pch_n_S (const void *x)
{
- ggc_mark_nonnull_tree (HT_IDENT_TO_GCC_IDENT (h));
- return 1;
+ gt_pch_note_object (CONST_CAST (void *, x), CONST_CAST (void *, x),
+ >_pch_p_S);
}
-/* Mark all identifiers for GC. */
-static void
-mark_ident_hash (arg)
- PTR arg ATTRIBUTE_UNUSED;
+/* User-callable entry point for marking string X. */
+
+void
+gt_pch_nx (const char *& x)
{
- ht_forall (ident_hash, mark_ident, NULL);
+ 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"