tree-vect-loop.c (vect_analyze_scalar_cycles_1): Do not add reduction chains to LOOP_VINFO_REDUCTIONS.

2017-06-29  Richard Biener  <rguenther@suse.de>

	* tree-vect-loop.c (vect_analyze_scalar_cycles_1): Do not add
	reduction chains to LOOP_VINFO_REDUCTIONS.
	* tree-vect-slp.c (vect_analyze_slp): Continue looking for
	SLP reductions after processing reduction chains.

	* gcc.dg/vect/slp-reduc-8.c: New testcase.

From-SVN: r249785