Add cselib; use it in loop and reload_cse_regs

From-SVN: r32538

1 files changed, 66 insertions, 0 deletions

diff --git a/gcc/cselib.h b/gcc/cselib.h
new file mode 100644
index 0000000..879b9c6
--- /dev/null
+++ b/gcc/cselib.h
@@ -0,0 +1,66 @@
+/* Common subexpression elimination for GNU compiler.
+   Copyright (C) 1987, 88, 89, 92-7, 1998, 1999 Free Software Foundation, Inc.
+
+This file is part of GNU CC.
+
+GNU CC 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 2, or (at your option)
+any later version.
+
+GNU CC 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 GNU CC; see the file COPYING.  If not, write to
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+/* Describe a value.  */
+typedef struct cselib_val_struct
+{
+  /* The hash value.  */
+  unsigned int value;
+  union
+  {
+    /* A VALUE rtx that points back to this structure.  */
+    rtx val_rtx;
+    /* Used to keep a list of free cselib_val structures.  */
+    struct cselib_val_struct *next_free;
+  } u;
+
+  /* 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;
+} cselib_val;
+
+/* 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 setting_insn;
+};
+
+/* A list of cselib_val structures.  */
+struct elt_list
+{
+  struct elt_list *next;
+  cselib_val *elt;
+};
+
+extern cselib_val *cselib_lookup	PARAMS ((rtx, enum machine_mode, int));
+extern void cselib_update_varray_sizes	PARAMS ((void));
+extern void cselib_init			PARAMS ((void));
+extern void cselib_finish		PARAMS ((void));
+extern void cselib_process_insn		PARAMS ((rtx));
+extern int rtx_equal_for_cselib_p	PARAMS ((rtx, rtx));
+extern int references_value_p		PARAMS ((rtx, int));