re PR tree-optimization/82929 (r254579 causes ICE: tree check: expected ssa_name, have array_ref in has_single_use, at ssa-iterators.h:400)

	PR tree-optimization/82929
	* gimple-ssa-store-merging.c (struct store_immediate_info): Add
	ops_swapped_p non-static data member.
	(store_immediate_info::store_immediate_info): Clear it.
	(imm_store_chain_info::coalesce_immediate_stores): If swapping
	ops set ops_swapped_p.
	(count_multiple_uses): Handle ops_swapped_p.

	* gcc.dg/pr82929.c: New test.
	* g++.dg/opt/pr82929.C: New test.

From-SVN: r254628