* cselib.h (cselib_add_permanent_equiv): Declare.

(canonical_cselib_val): New.
* cselib.c (new_elt_loc_list): Rework to support value
equivalences.  Adjust all callers.
(preserve_only_constants): Retain value equivalences.
(references_value_p): Retain preserved values.
(rtx_equal_for_cselib_1): Handle value equivalences.
(cselib_invalidate_regno): Use canonical value.
(cselib_add_permanent_equiv): New.
* alias.c (find_base_term): Reset locs lists while recursing.
* var-tracking.c (val_bind): New.  Don't add equivalences
present in cselib table, compared with code moved from...
(val_store): ... here.
(val_resolve): Use val_bind.
(VAL_EXPR_HAS_REVERSE): Drop.
(add_uses): Do not create MOps for addresses.  Do not mark
non-REG non-MEM expressions as requiring resolution.
(reverse_op): Record reverse as a cselib equivalence.
(add_stores): Use it.  Do not create MOps for addresses.
Do not require resolution for non-REG non-MEM expressions.
Simplify support for reverse operations.
(compute_bb_dataflow): Drop reverse support.
(emit_notes_in_bb): Likewise.
(create_entry_value): Rename to...
(record_entry_value): ... this.  Use cselib equivalences.
(vt_add_function_parameter): Adjust.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@182760 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 21 insertions, 6 deletions

diff --git a/gcc/alias.c b/gcc/alias.c
index ef624a1bfe4..37c3fa062cf 100644
--- a/gcc/alias.c
+++ b/gcc/alias.c
@@ -1542,7 +1542,8 @@ rtx
 find_base_term (rtx x)
 {
   cselib_val *val;
-  struct elt_loc_list *l;
+  struct elt_loc_list *l, *f;
+  rtx ret;
 
 #if defined (FIND_BASE_TERM)
   /* Try machine-dependent ways to find the base term.  */
@@ -1591,12 +1592,26 @@ find_base_term (rtx x)
 
     case VALUE:
       val = CSELIB_VAL_PTR (x);
+      ret = NULL_RTX;
+
       if (!val)
-	return 0;
-      for (l = val->locs; l; l = l->next)
-	if ((x = find_base_term (l->loc)) != 0)
-	  return x;
-      return 0;
+	return ret;
+
+      f = val->locs;
+      /* Temporarily reset val->locs to avoid infinite recursion.  */
+      val->locs = NULL;
+
+      for (l = f; l; l = l->next)
+	if (GET_CODE (l->loc) == VALUE
+	    && CSELIB_VAL_PTR (l->loc)->locs
+	    && !CSELIB_VAL_PTR (l->loc)->locs->next
+	    && CSELIB_VAL_PTR (l->loc)->locs->loc == x)
+	  continue;
+	else if ((ret = find_base_term (l->loc)) != 0)
+	  break;
+
+      val->locs = f;
+      return ret;
 
     case LO_SUM:
       /* The standard form is (lo_sum reg sym) so look only at the