Line data    Source code

       1              : /* Common subexpression elimination for GNU compiler.
       2              :    Copyright (C) 1987-2026 Free Software Foundation, Inc.
       3              : 
       4              : This file is part of GCC.
       5              : 
       6              : GCC is free software; you can redistribute it and/or modify it under
       7              : the terms of the GNU General Public License as published by the Free
       8              : Software Foundation; either version 3, or (at your option) any later
       9              : version.
      10              : 
      11              : GCC is distributed in the hope that it will be useful, but WITHOUT ANY
      12              : WARRANTY; without even the implied warranty of MERCHANTABILITY or
      13              : FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
      14              : for more details.
      15              : 
      16              : You should have received a copy of the GNU General Public License
      17              : along with GCC; see the file COPYING3.  If not see
      18              : <http://www.gnu.org/licenses/>.  */
      19              : 
      20              : #ifndef GCC_CSELIB_H
      21              : #define GCC_CSELIB_H
      22              : 
      23              : /* Describe a value.  */
      24              : struct cselib_val
      25              : {
      26              :   /* The hash value.  */
      27              :   unsigned int hash;
      28              : 
      29              :   /* A unique id assigned to values.  */
      30              :   int uid;
      31              : 
      32              :   /* A VALUE rtx that points back to this structure.  */
      33              :   rtx val_rtx;
      34              : 
      35              :   /* All rtl expressions that hold this value at the current time during a
      36              :      scan.  */
      37              :   struct elt_loc_list *locs;
      38              : 
      39              :   /* If this value is used as an address, points to a list of values that
      40              :      use it as an address in a MEM.  */
      41              :   struct elt_list *addr_list;
      42              : 
      43              :   struct cselib_val *next_containing_mem;
      44              : };
      45              : 
      46              : /* A list of rtl expressions that hold the same value.  */
      47              : struct elt_loc_list {
      48              :   /* Next element in the list.  */
      49              :   struct elt_loc_list *next;
      50              :   /* An rtl expression that holds the value.  */
      51              :   rtx loc;
      52              :   /* The insn that made the equivalence.  */
      53              :   rtx_insn *setting_insn;
      54              : };
      55              : 
      56              : /* Describe a single set that is part of an insn.  */
      57              : struct cselib_set
      58              : {
      59              :   rtx src;
      60              :   rtx dest;
      61              :   cselib_val *src_elt;
      62              :   cselib_val *dest_addr_elt;
      63              : };
      64              : 
      65              : enum cselib_record_what
      66              : {
      67              :   CSELIB_RECORD_MEMORY = 1,
      68              :   CSELIB_PRESERVE_CONSTANTS = 2
      69              : };
      70              : 
      71              : extern void (*cselib_discard_hook) (cselib_val *);
      72              : extern void (*cselib_record_sets_hook) (rtx_insn *insn, struct cselib_set *sets,
      73              :                                         int n_sets);
      74              : 
      75              : extern cselib_val *cselib_lookup (rtx, machine_mode,
      76              :                                   int, machine_mode);
      77              : extern cselib_val *cselib_lookup_from_insn (rtx, machine_mode,
      78              :                                             int, machine_mode, rtx_insn *);
      79              : extern void cselib_init (int);
      80              : extern void cselib_clear_table (void);
      81              : extern void cselib_finish (void);
      82              : extern void cselib_process_insn (rtx_insn *);
      83              : extern bool fp_setter_insn (rtx_insn *);
      84              : extern machine_mode cselib_reg_set_mode (const_rtx);
      85              : extern bool rtx_equal_for_cselib_1 (rtx, rtx, machine_mode, int);
      86              : extern bool cselib_redundant_set_p (rtx);
      87              : extern bool references_value_p (const_rtx, int);
      88              : extern rtx cselib_expand_value_rtx (rtx, bitmap, int);
      89              : typedef rtx (*cselib_expand_callback)(rtx, bitmap, int, void *);
      90              : extern rtx cselib_expand_value_rtx_cb (rtx, bitmap, int,
      91              :                                        cselib_expand_callback, void *);
      92              : extern bool cselib_dummy_expand_value_rtx_cb (rtx, bitmap, int,
      93              :                                               cselib_expand_callback, void *);
      94              : extern rtx cselib_subst_to_values (rtx, machine_mode);
      95              : extern rtx cselib_subst_to_values_from_insn (rtx, machine_mode, rtx_insn *);
      96              : extern void cselib_invalidate_rtx (rtx);
      97              : 
      98              : extern void cselib_reset_table (unsigned int);
      99              : extern unsigned int cselib_get_next_uid (void);
     100              : extern void cselib_preserve_value (cselib_val *);
     101              : extern bool cselib_preserved_value_p (cselib_val *);
     102              : extern void cselib_preserve_only_values (void);
     103              : extern void cselib_preserve_cfa_base_value (cselib_val *, unsigned int);
     104              : extern void cselib_add_permanent_equiv (cselib_val *, rtx, rtx_insn *);
     105              : extern bool cselib_have_permanent_equivalences (void);
     106              : extern void cselib_set_value_sp_based (cselib_val *);
     107              : extern bool cselib_sp_based_value_p (cselib_val *);
     108              : extern void cselib_record_sp_cfa_base_equiv (HOST_WIDE_INT, rtx_insn *);
     109              : extern bool cselib_sp_derived_value_p (cselib_val *);
     110              : 
     111              : extern void dump_cselib_table (FILE *);
     112              : 
     113              : /* Return the canonical value for VAL, following the equivalence chain
     114              :    towards the earliest (== lowest uid) equivalent value.  */
     115              : 
     116              : inline cselib_val *
     117   2405016678 : canonical_cselib_val (cselib_val *val)
     118              : {
     119   2405016678 :   cselib_val *canon;
     120              : 
     121   2405016678 :   if (!val->locs || val->locs->next
     122    833981902 :       || !val->locs->loc || GET_CODE (val->locs->loc) != VALUE
     123     19078975 :       || val->uid < CSELIB_VAL_PTR (val->locs->loc)->uid)
     124              :     return val;
     125              : 
     126     19067397 :   canon = CSELIB_VAL_PTR (val->locs->loc);
     127     19067397 :   gcc_checking_assert (canonical_cselib_val (canon) == canon);
     128              :   return canon;
     129              : }
     130              : 
     131              : /* Return true if we can prove that X and Y contain the same value, taking
     132              :    our gathered information into account.  */
     133              : 
     134              : inline bool
     135     54811326 : rtx_equal_for_cselib_p (rtx x, rtx y)
     136              : {
     137     54811326 :   if (x == y)
     138              :     return true;
     139              : 
     140     54795536 :   return rtx_equal_for_cselib_1 (x, y, VOIDmode, 0);
     141              : }
     142              : 
     143              : #endif /* GCC_CSELIB_H */