PR tree-optimization/46009
	* tree-ssa-phiopt.c (tree_ssa_phiopt_worker): Call
	cond_if_else_store_replacement if bb1 and bb2 have the same
	single successor.
	(cond_store_replacement): Use gimple_assign_single_p, don't
	check if rhs is SSA_NAME or invariant.  Call release_defs for
	assign.
	(cond_if_else_store_replacement): New function.

	* gcc.dg/vect/pr46009.c: New function.

From-SVN: r166251