2017-11-23  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/81403
	* tree-ssa-pre.c (get_representative_for): Add parameter specifying
	a block we need a leader relative to.
	(phi_translate_1): For nary processing require a leader from
	get_representative_for given we run expression simplification
	using match-and-simplify.  Remove previous fix.

From-SVN: r255092