| /* Common subexpression elimination for GNU compiler. |
| Copyright (C) 1987-2020 Free Software Foundation, Inc. |
| |
| This file is part of GCC. |
| |
| GCC 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 3, or (at your option) any later |
| version. |
| |
| GCC 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 GCC; see the file COPYING3. If not see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #ifndef GCC_CSELIB_H |
| #define GCC_CSELIB_H |
| |
| /* Describe a value. */ |
| struct cselib_val |
| { |
| /* The hash value. */ |
| unsigned int hash; |
| |
| /* A unique id assigned to values. */ |
| int uid; |
| |
| /* A VALUE rtx that points back to this structure. */ |
| rtx val_rtx; |
| |
| /* 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; |
| |
| struct cselib_val *next_containing_mem; |
| }; |
| |
| /* 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_insn *setting_insn; |
| }; |
| |
| /* Describe a single set that is part of an insn. */ |
| struct cselib_set |
| { |
| rtx src; |
| rtx dest; |
| cselib_val *src_elt; |
| cselib_val *dest_addr_elt; |
| }; |
| |
| enum cselib_record_what |
| { |
| CSELIB_RECORD_MEMORY = 1, |
| CSELIB_PRESERVE_CONSTANTS = 2 |
| }; |
| |
| extern void (*cselib_discard_hook) (cselib_val *); |
| extern void (*cselib_record_sets_hook) (rtx_insn *insn, struct cselib_set *sets, |
| int n_sets); |
| |
| extern cselib_val *cselib_lookup (rtx, machine_mode, |
| int, machine_mode); |
| extern cselib_val *cselib_lookup_from_insn (rtx, machine_mode, |
| int, machine_mode, rtx_insn *); |
| extern void cselib_init (int); |
| extern void cselib_clear_table (void); |
| extern void cselib_finish (void); |
| extern void cselib_process_insn (rtx_insn *); |
| extern bool fp_setter_insn (rtx_insn *); |
| extern machine_mode cselib_reg_set_mode (const_rtx); |
| extern int rtx_equal_for_cselib_1 (rtx, rtx, machine_mode, int); |
| extern int references_value_p (const_rtx, int); |
| extern rtx cselib_expand_value_rtx (rtx, bitmap, int); |
| typedef rtx (*cselib_expand_callback)(rtx, bitmap, int, void *); |
| extern rtx cselib_expand_value_rtx_cb (rtx, bitmap, int, |
| cselib_expand_callback, void *); |
| extern bool cselib_dummy_expand_value_rtx_cb (rtx, bitmap, int, |
| cselib_expand_callback, void *); |
| extern rtx cselib_subst_to_values (rtx, machine_mode); |
| extern rtx cselib_subst_to_values_from_insn (rtx, machine_mode, rtx_insn *); |
| extern void cselib_invalidate_rtx (rtx); |
| |
| extern void cselib_reset_table (unsigned int); |
| extern unsigned int cselib_get_next_uid (void); |
| extern void cselib_preserve_value (cselib_val *); |
| extern bool cselib_preserved_value_p (cselib_val *); |
| extern void cselib_preserve_only_values (void); |
| extern void cselib_preserve_cfa_base_value (cselib_val *, unsigned int); |
| extern void cselib_add_permanent_equiv (cselib_val *, rtx, rtx_insn *); |
| extern bool cselib_have_permanent_equivalences (void); |
| extern void cselib_set_value_sp_based (cselib_val *); |
| extern bool cselib_sp_based_value_p (cselib_val *); |
| extern void cselib_record_sp_cfa_base_equiv (HOST_WIDE_INT, rtx_insn *); |
| extern bool cselib_sp_derived_value_p (cselib_val *); |
| |
| extern void dump_cselib_table (FILE *); |
| |
| /* Return the canonical value for VAL, following the equivalence chain |
| towards the earliest (== lowest uid) equivalent value. */ |
| |
| static inline cselib_val * |
| canonical_cselib_val (cselib_val *val) |
| { |
| cselib_val *canon; |
| |
| if (!val->locs || val->locs->next |
| || !val->locs->loc || GET_CODE (val->locs->loc) != VALUE |
| || val->uid < CSELIB_VAL_PTR (val->locs->loc)->uid) |
| return val; |
| |
| canon = CSELIB_VAL_PTR (val->locs->loc); |
| gcc_checking_assert (canonical_cselib_val (canon) == canon); |
| return canon; |
| } |
| |
| /* Return nonzero if we can prove that X and Y contain the same value, taking |
| our gathered information into account. */ |
| |
| static inline int |
| rtx_equal_for_cselib_p (rtx x, rtx y) |
| { |
| if (x == y) |
| return 1; |
| |
| return rtx_equal_for_cselib_1 (x, y, VOIDmode, 0); |
| } |
| |
| #endif /* GCC_CSELIB_H */ |