tree-vect-loop.c (vect_analyze_scalar_cycles_1): Disregard sign-changing…

tree-vect-loop.c (vect_analyze_scalar_cycles_1): Disregard sign-changing conversions for induction detection.

2010-12-02  Richard Guenther  <rguenther@suse.de>

	* tree-vect-loop.c (vect_analyze_scalar_cycles_1): Disregard
	sign-changing conversions for induction detection.

From-SVN: r167378

gcc/ChangeLog

 2010-12-02  Richard Guenther  <rguenther@suse.de>
 
+	* tree-vect-loop.c (vect_analyze_scalar_cycles_1): Disregard
+	sign-changing conversions for induction detection.
+
+2010-12-02  Richard Guenther  <rguenther@suse.de>
+
 	PR tree-optimization/46723
 	* tree-vect-loop.c (get_initial_def_for_induction): Strip
 	conversions from the induction evolution and apply it to

gcc/tree-vect-loop.c

@@ -478,6 +478,8 @@ vect_analyze_scalar_cycles_1 (loop_vec_info loop_vinfo, struct loop *loop)
 
       /* Analyze the evolution function.  */
       access_fn = analyze_scalar_evolution (loop, def);
+      if (access_fn)
+	STRIP_NOPS (access_fn);
       if (access_fn && vect_print_dump_info (REPORT_DETAILS))
 	{
 	  fprintf (vect_dump, "Access function of PHI: ");