2015-10-09  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/67891
	* gimple-match.h (gimple_simplified_result_is_gimple_val):
	New helper.
	(gimple_resimplify1): Declare.
	(gimple_resimplify2): Likewise.
	(gimple_resimplify3): Likewise.
	* gimple-match-head.c (gimple_resimplify1): Export.
	(gimple_resimplify2): Likewise.
	(gimple_resimplify3): Likewise.
	(maybe_push_res_to_seq): Use gimple_simplified_result_is_gimple_val.
	* gimple-fold.c (gimple_fold_stmt_to_constant_1): Likewise.
	* tree-ssa-sccvn.c (visit_reference_op_load): Use gimple_resimplify1
	to avoid creating stmts without VN info.

	* gcc.dg/tree-ssa/pr67891.c: New testcase.

From-SVN: r228635