2015-10-23  Steve Ellcey  <sellcey@imgtec.com>
	    Andrew Pinski  <apinski@cavium.com>

	PR rtl-optimization/67736
	* combine.c (simplify_comparison): Use gen_lowpart_or_truncate instead
	of gen_lowpart.

Co-Authored-By: Andrew Pinski <apinski@cavium.com>

From-SVN: r229259