Add debug function for affine_iv

	* tree-ssa-loop-niter.cc (dump_affine_iv): Use file, not
	dump_file when printing.
	(debug): New overload for affine_iv.

Author: rguenth

gcc/tree-ssa-loop-niter.cc

@@ -1752,16 +1752,23 @@ dump_affine_iv (FILE *file, affine_iv *iv)
   if (!integer_zerop (iv->step))
     fprintf (file, "[");
 
-  print_generic_expr (dump_file, iv->base, TDF_SLIM);
+  print_generic_expr (file, iv->base, TDF_SLIM);
 
   if (!integer_zerop (iv->step))
     {
       fprintf (file, ", + , ");
-      print_generic_expr (dump_file, iv->step, TDF_SLIM);
+      print_generic_expr (file, iv->step, TDF_SLIM);
       fprintf (file, "]%s", iv->no_overflow ? "(no_overflow)" : "");
     }
 }
 
+DEBUG_FUNCTION void
+debug (affine_iv *iv)
+{
+  dump_affine_iv (stderr, iv);
+  fputc ('\n', stderr);
+}
+
 /* Determine the number of iterations according to condition (for staying
    inside loop) which compares two induction variables using comparison
    operator CODE.  The induction variable on left side of the comparison