2008-08-17 Paul Thomas <pault@gcc.gnu.org>
[official-gcc.git] / gcc / cselib.h
blobfccc6a2cd32fcff970625a279bea5bde9aff80cd
1 /* Common subexpression elimination for GNU compiler.
2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 /* Describe a value. */
22 typedef struct GTY(()) cselib_val_struct {
23 /* The hash value. */
24 unsigned int value;
26 /* A VALUE rtx that points back to this structure. */
27 rtx val_rtx;
29 /* All rtl expressions that hold this value at the current time during a
30 scan. */
31 struct elt_loc_list *locs;
33 /* If this value is used as an address, points to a list of values that
34 use it as an address in a MEM. */
35 struct elt_list *addr_list;
37 struct cselib_val_struct *next_containing_mem;
38 } cselib_val;
40 /* A list of rtl expressions that hold the same value. */
41 struct GTY(()) elt_loc_list {
42 /* Next element in the list. */
43 struct elt_loc_list *next;
44 /* An rtl expression that holds the value. */
45 rtx loc;
46 /* The insn that made the equivalence. */
47 rtx setting_insn;
50 /* A list of cselib_val structures. */
51 struct GTY(()) elt_list {
52 struct elt_list *next;
53 cselib_val *elt;
56 extern void (*cselib_discard_hook) (cselib_val *);
58 extern cselib_val *cselib_lookup (rtx, enum machine_mode, int);
59 extern void cselib_init (bool record_memory);
60 extern void cselib_clear_table (void);
61 extern void cselib_finish (void);
62 extern void cselib_process_insn (rtx);
63 extern enum machine_mode cselib_reg_set_mode (const_rtx);
64 extern int rtx_equal_for_cselib_p (rtx, rtx);
65 extern int references_value_p (const_rtx, int);
66 extern rtx cselib_expand_value_rtx (rtx, bitmap, int);
67 extern rtx cselib_subst_to_values (rtx);
68 extern void cselib_invalidate_rtx (rtx);