* tree-ssa-loop-ivopts.c (strip_offset_1) <MULT_EXPR>: New case.
	(force_expr_to_var_cost) <NEGATE_EXPR>: Likewise.
	(ptr_difference_cost): Use affine combinations to compute it.
	(difference_cost): Likewise.
	(get_computation_cost_at): Compute more accurate cost for addresses
	if the ratio is a multiplier allowed in addresses.
	For non-addresses, consider that an additional offset or symbol is
	added only once.

From-SVN: r147983