diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index bde5e915515..3241bbd3857 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+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
diff --git a/gcc/tree-vect-loop.c b/gcc/tree-vect-loop.c
index 7a562b124c0..3aa77d6ec10 100644
--- a/gcc/tree-vect-loop.c
+++ b/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: ");