gcc/cselib.h

   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 Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   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.
  11
  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.
  16
  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/>.  */
  20
  21 /* Describe a value.  */
  22 typedef struct cselib_val_struct GTY(())
  23 {
  24   /* The hash value.  */
  25   unsigned int value;
  26
  27   /* A VALUE rtx that points back to this structure.  */
  28   rtx val_rtx;
  29
  30   /* All rtl expressions that hold this value at the current time during a
  31      scan.  */
  32   struct elt_loc_list *locs;
  33
  34   /* If this value is used as an address, points to a list of values that
  35      use it as an address in a MEM.  */
  36   struct elt_list *addr_list;
  37
  38   struct cselib_val_struct *next_containing_mem;
  39 } cselib_val;
  40
  41 /* A list of rtl expressions that hold the same value.  */
  42 struct elt_loc_list GTY(())
  43 {
  44   /* Next element in the list.  */
  45   struct elt_loc_list *next;
  46   /* An rtl expression that holds the value.  */
  47   rtx loc;
  48   /* The insn that made the equivalence.  */
  49   rtx setting_insn;
  50 };
  51
  52 /* A list of cselib_val structures.  */
  53 struct elt_list GTY(())
  54 {
  55   struct elt_list *next;
  56   cselib_val *elt;
  57 };
  58
  59 extern void (*cselib_discard_hook) (cselib_val *);
  60
  61 extern cselib_val *cselib_lookup (rtx, enum machine_mode, int);
  62 extern void cselib_init (bool record_memory);
  63 extern void cselib_clear_table (void);
  64 extern void cselib_finish (void);
  65 extern void cselib_process_insn (rtx);
  66 extern enum machine_mode cselib_reg_set_mode (const_rtx);
  67 extern int rtx_equal_for_cselib_p (rtx, rtx);
  68 extern int references_value_p (const_rtx, int);
  69 extern rtx cselib_expand_value_rtx (rtx, bitmap, int);
  70 extern rtx cselib_subst_to_values (rtx);
  71 extern void cselib_invalidate_rtx (rtx);