/* Common subexpression elimination for GNU compiler.
Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997,
- 1998, 1999, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
+ 1998, 1999, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
Free Software Foundation, Inc.
This file is part of GCC.
extern void (*cselib_record_sets_hook) (rtx insn, struct cselib_set *sets,
int n_sets);
-extern cselib_val *cselib_lookup (rtx, enum machine_mode, int);
-extern cselib_val *cselib_lookup_from_insn (rtx, enum machine_mode, int, rtx);
+extern cselib_val *cselib_lookup (rtx, enum machine_mode,
+ int, enum machine_mode);
+extern cselib_val *cselib_lookup_from_insn (rtx, enum machine_mode,
+ int, enum machine_mode, rtx);
extern void cselib_init (int);
extern void cselib_clear_table (void);
extern void cselib_finish (void);
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);
+extern rtx cselib_subst_to_values (rtx, enum machine_mode);
+extern rtx cselib_subst_to_values_from_insn (rtx, enum machine_mode, rtx);
extern void cselib_invalidate_rtx (rtx);
extern void cselib_reset_table (unsigned int);
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);
+extern bool cselib_have_permanent_equivalences (void);
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;
+}