gcc/gcc/cselib.h
2000-03-14 18:36:18 +00:00

67 lines
2.1 KiB
C

/* Common subexpression elimination for GNU compiler.
Copyright (C) 1987, 88, 89, 92-7, 1998, 1999 Free Software Foundation, Inc.
This file is part of GNU CC.
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.
GNU CC 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. */
/* Describe a value. */
typedef struct cselib_val_struct
{
/* The hash value. */
unsigned int value;
union
{
/* A VALUE rtx that points back to this structure. */
rtx val_rtx;
/* Used to keep a list of free cselib_val structures. */
struct cselib_val_struct *next_free;
} u;
/* All rtl expressions that hold this value at the current time during a
scan. */
struct elt_loc_list *locs;
/* If this value is used as an address, points to a list of values that
use it as an address in a MEM. */
struct elt_list *addr_list;
} cselib_val;
/* A list of rtl expressions that hold the same value. */
struct elt_loc_list
{
/* Next element in the list. */
struct elt_loc_list *next;
/* An rtl expression that holds the value. */
rtx loc;
/* The insn that made the equivalence. */
rtx setting_insn;
};
/* A list of cselib_val structures. */
struct elt_list
{
struct elt_list *next;
cselib_val *elt;
};
extern cselib_val *cselib_lookup PARAMS ((rtx, enum machine_mode, int));
extern void cselib_update_varray_sizes PARAMS ((void));
extern void cselib_init PARAMS ((void));
extern void cselib_finish PARAMS ((void));
extern void cselib_process_insn PARAMS ((rtx));
extern int rtx_equal_for_cselib_p PARAMS ((rtx, rtx));
extern int references_value_p PARAMS ((rtx, int));