loop.h (struct iv): New.

	* loop.h (struct iv): New.
	(REG_IV_TYPE, REG_IV_CLASS, REG_INFO): Modify to use 'struct iv'.
	(struct loop_ivs): Replace 'reg_iv_type', 'reg_iv_info',
	'reg_biv_class' fields with 'regs' and 'n_regs'.
	(struct ivs): Rename 'loop_iv_list' field to 'list'.
	* loop.c (loop_bivs_find, strength_reduce): Use ivs->regs array.
	* unroll.c (loop_iterations): Check array bounds with ivs->n_regs.

From-SVN: r38582