Allow non-overflow ops in reductions

Allow non-overflow ops in reductions

2015-08-01  Tom de Vries  <tom@codesourcery.com>

	* tree.c (operation_can_overflow, operation_no_trapping_overflow): New
	function.
	* tree.h (operation_can_overflow, operation_no_trapping_overflow):
	Declare.
	* tree-vect-loop.c (vect_is_simple_reduction_1): Use
	operation_no_trapping_overflow.  Allow non-overflow operations.
	* graphite-sese-to-poly.c (is_reduction_operation_p): Allow non-overflow
	operations.

	* gcc.dg/autopar/reduc-2char.c (init_arrays): Mark with attribute
	optimize ("-ftree-parallelize-loops=0").
	Add successful scans for 2 detected reductions.	 Add xfail scans for 3
	detected reductions.
	* gcc.dg/autopar/reduc-2short.c: Same.
	* gcc.dg/autopar/reduc-8.c (init_arrays): Mark with attribute
	optimize ("-ftree-parallelize-loops=0").  Add successful scans for 2
	detected reductions.
	* gcc.dg/vect/trapv-vect-reduc-4.c: Update scan to match vectorized min
	and max reductions.

From-SVN: r226463