tree-ssa-loop-ivopts.c (determine_iv_cost): Do not try to preserve artificial original candidates.

	* tree-ssa-loop-ivopts.c (determine_iv_cost): Do not try to preserve
	artificial original candidates.

From-SVN: r96894

gcc/ChangeLog

+2005-03-22  Zdenek Dvorak  <dvorakz@suse.cz>
+
+	* tree-ssa-loop-ivopts.c (determine_iv_cost): Do not try to preserve
+	artificial original candidates.
+
 2005-03-22  Richard Guenther <rguenth@tat.physik.uni-tuebingen.de>
 	    Jan Hubicka  <jh@suse.cz>
 	    Steven Bosscher <stevenb@suse.de

gcc/tree-ssa-loop-ivopts.c

@@ -3681,8 +3681,11 @@ determine_iv_cost (struct ivopts_data *data, struct iv_cand *cand)
 
   cand->cost = cost_step + cost_base / AVG_LOOP_NITER (current_loop);
 
-  /* Prefer the original iv unless we may gain something by replacing it.  */
-  if (cand->pos == IP_ORIGINAL)
+  /* Prefer the original iv unless we may gain something by replacing it;
+     this is not really relevant for artificial ivs created by other
+     passes.  */
+  if (cand->pos == IP_ORIGINAL
+      && !DECL_ARTIFICIAL (SSA_NAME_VAR (cand->var_before)))
     cand->cost--;
   
   /* Prefer not to insert statements into latch unless there are some