* loop.h (struct loop_reg): New.
	(struct loop_regs): Change to use array of `struct loop_reg'.
	* loop.c: Replace assortment of varrays with single regs array.
	(count_one_set): Delete may_not_move array argument
	and use regs array instead.  All caller's changed.
	(count_loop_regs_set): Delete may_not_move and single_usage
	arguments and use regs array instead.  All caller's changed.
	(find_single_use_in_loop): Replace usage array argument with pointer
	to regs structure.  All caller's changed.
	(loop_optimize): Delete `moved_once' array.

From-SVN: r38700