re PR tree-optimization/69728 (internal compiler error: in outer_projection_mupa, at graphite-sese-to-poly.c:1175)

2017-10-12  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/69728
	Revert
	2017-09-19  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/69728
	* graphite-sese-to-poly.c (schedule_error): New global.
	(add_loop_schedule): Handle empty domain by failing the
	schedule.
	(build_original_schedule): Handle schedule_error.

	* graphite-sese-to-poly.c (add_loop_schedule): Handle empty
	domain by returning an unchanged schedule.

	* gcc.dg/graphite/pr69728.c: Adjust to reflect we can handle
	the loop now.  Remove unrelated undefined behavior.

From-SVN: r253677