freebsd-skq/contrib/gcc/hashtable.h
2003-07-11 03:40:53 +00:00

92 lines
3.0 KiB
C

/* Hash tables.
Copyright (C) 2000, 2001 Free Software Foundation, Inc.
This program 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.
This program 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 this program; if not, write to the Free Software
Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#ifndef GCC_HASHTABLE_H
#define GCC_HASHTABLE_H
#include "obstack.h"
/* This is what each hash table entry points to. It may be embedded
deeply within another object. */
typedef struct ht_identifier ht_identifier;
struct ht_identifier GTY(())
{
const unsigned char *str;
unsigned int len;
unsigned int hash_value;
};
#define HT_LEN(NODE) ((NODE)->len)
#define HT_STR(NODE) ((NODE)->str)
/* We want code outside cpplib, such as the compiler front-ends, to be
able to include this header, and to be able to link with
cpphashtbl.o without pulling in any other parts of cpplib. */
struct cpp_reader;
typedef struct ht hash_table;
typedef struct ht_identifier *hashnode;
enum ht_lookup_option {HT_NO_INSERT = 0, HT_ALLOC, HT_ALLOCED};
/* An identifier hash table for cpplib and the front ends. */
struct ht
{
/* Identifiers are allocated from here. */
struct obstack stack;
hashnode *entries;
/* Call back. */
hashnode (*alloc_node) PARAMS ((hash_table *));
unsigned int nslots; /* Total slots in the entries array. */
unsigned int nelements; /* Number of live elements. */
/* Link to reader, if any. For the benefit of cpplib. */
struct cpp_reader *pfile;
/* Table usage statistics. */
unsigned int searches;
unsigned int collisions;
};
extern void gcc_obstack_init PARAMS ((struct obstack *));
/* Initialize the hashtable with 2 ^ order entries. */
extern hash_table *ht_create PARAMS ((unsigned int order));
/* Frees all memory associated with a hash table. */
extern void ht_destroy PARAMS ((hash_table *));
extern hashnode ht_lookup PARAMS ((hash_table *, const unsigned char *,
unsigned int, enum ht_lookup_option));
/* For all nodes in TABLE, make a callback. The callback takes
TABLE->PFILE, the node, and a PTR, and the callback sequence stops
if the callback returns zero. */
typedef int (*ht_cb) PARAMS ((struct cpp_reader *, hashnode, const void *));
extern void ht_forall PARAMS ((hash_table *, ht_cb, const void *));
/* Dump allocation statistics to stderr. */
extern void ht_dump_statistics PARAMS ((hash_table *));
/* Approximate positive square root of a host double. This is for
statistical reports, not code generation. */
extern double approx_sqrt PARAMS ((double));
#endif /* GCC_HASHTABLE_H */