tree-ssa-copy.c (fini_copy_prop): Don't DCE when we have loops.

	* tree-ssa-copy.c (fini_copy_prop): Don't DCE when we have loops.

	* passes.c (init_optimization_passes): Remove superfluous
	copy-prop pass.

From-SVN: r167184

gcc/ChangeLog

+2010-11-26  Michael Matz  <matz@suse.de>
+
+	* tree-ssa-copy.c (fini_copy_prop): Don't DCE when we have loops.
+
+	* passes.c (init_optimization_passes): Remove superfluous
+	copy-prop pass.
+
 2010-11-26  Richard Guenther  <rguenther@suse.de>
 
 	PR lto/46648

gcc/passes.c

@@ -897,7 +897,6 @@ init_optimization_passes (void)
 	  NEXT_PASS (pass_graphite);
 	    {
 	      struct opt_pass **p = &pass_graphite.pass.sub;
-	      NEXT_PASS (pass_copy_prop);
 	      NEXT_PASS (pass_graphite_transforms);
 	      NEXT_PASS (pass_copy_prop);
 	      NEXT_PASS (pass_dce_loop);

gcc/tree-ssa-copy.c

@@ -775,7 +775,9 @@ fini_copy_prop (void)
 	duplicate_ssa_name_ptr_info (copy_of[i].value, SSA_NAME_PTR_INFO (var));
     }
 
-  substitute_and_fold (get_value, NULL, true);
+  /* Don't do DCE if we have loops.  That's the simplest way to not
+     destroy the scev cache.  */
+  substitute_and_fold (get_value, NULL, !current_loops);
 
   free (copy_of);
 }