re PR tree-optimization/22335 (DOM creates mis-matched types)

2005-07-12  Andrew Pinski  <pinskia@physics.uc.edu>

        PR tree-opt/22335
        * tree-ssa-dom.c (eliminate_redundant_computations): Reject the prop if
        requiring a cast in a non RHS of modify_expr.  Add a cast when required.
        (lookup_avail_expr): Use constant_boolean_node instead
        of boolean_false_node/boolean_true_node.

From-SVN: r101929

gcc/ChangeLog

+2005-07-12  Andrew Pinski  <pinskia@physics.uc.edu>
+
+	PR tree-opt/22335
+	* tree-ssa-dom.c (eliminate_redundant_computations): Reject the prop if
+	requiring a cast in a non RHS of modify_expr.  Add a cast when required.
+	(lookup_avail_expr): Use constant_boolean_node instead
+	of boolean_false_node/boolean_true_node.
+
 2005-07-12  Ben Elliston  <bje@au.ibm.com>
 
 	* tree-cfg.c (dump_cfg_stats): Add a new fmt_str_2 format string

gcc/tree-ssa-dom.c

@@ -2506,6 +2506,7 @@ eliminate_redundant_computations (tree stmt, stmt_ann_t ann)
   bool insert = true;
   tree cached_lhs;
   bool retval = false;
+  bool modify_expr_p = false;
 
   if (TREE_CODE (stmt) == MODIFY_EXPR)
     def = TREE_OPERAND (stmt, 0);
@@ -2547,9 +2548,15 @@ eliminate_redundant_computations (tree stmt, stmt_ann_t ann)
   else if (TREE_CODE (stmt) == SWITCH_EXPR)
     expr_p = &SWITCH_COND (stmt);
   else if (TREE_CODE (stmt) == RETURN_EXPR && TREE_OPERAND (stmt, 0))
+    {
       expr_p = &TREE_OPERAND (TREE_OPERAND (stmt, 0), 1);
+      modify_expr_p = true;
+    }
   else
+    {
       expr_p = &TREE_OPERAND (stmt, 1);
+      modify_expr_p = true;
+    }
 
   /* It is safe to ignore types here since we have already done
      type checking in the hashing and equality routines.  In fact
@@ -2557,7 +2564,10 @@ eliminate_redundant_computations (tree stmt, stmt_ann_t ann)
      propagation.  Also, make sure that it is safe to propagate
      CACHED_LHS into *EXPR_P.  */
   if (cached_lhs
-      && (TREE_CODE (cached_lhs) != SSA_NAME
+      && ((TREE_CODE (cached_lhs) != SSA_NAME
+	   && (modify_expr_p
+	       || tree_ssa_useless_type_conversion_1 (TREE_TYPE (*expr_p),
+						      TREE_TYPE (cached_lhs))))
 	  || may_propagate_copy (*expr_p, cached_lhs)))
     {
       if (dump_file && (dump_flags & TDF_DETAILS))
@@ -2581,6 +2591,11 @@ eliminate_redundant_computations (tree stmt, stmt_ann_t ann)
 	      && is_gimple_min_invariant (cached_lhs)))
 	retval = true;
       
+      if (modify_expr_p
+	  && !tree_ssa_useless_type_conversion_1 (TREE_TYPE (*expr_p),
+						  TREE_TYPE (cached_lhs)))
+	cached_lhs = fold_convert (TREE_TYPE (*expr_p), cached_lhs);
+
       propagate_tree_value (expr_p, cached_lhs);
       mark_stmt_modified (stmt);
     }
@@ -3088,11 +3103,8 @@ lookup_avail_expr (tree stmt, bool insert)
 	{
 	  tree t = element->rhs;
 	  free (element);
-
-	  if (TREE_CODE (t) == EQ_EXPR)
-	    return boolean_false_node;
-	  else
-	    return boolean_true_node;
+	  return constant_boolean_node (TREE_CODE (t) != EQ_EXPR,
+					TREE_TYPE (element->rhs));
 	}
     }