Add side effect infrastructure.

Add side effect infrastructure.

Replace the non-null procesing with a generic side effect implementation that
can handle arbitrary side effects.

	* Makefile.in (OBJS): Add gimple-range-side-effect.o.
	* gimple-range-cache.cc (non_null_ref::non_null_ref): Delete.
	(non_null_ref::~non_null_ref): Delete.
	(non_null_ref::set_nonnull): Delete.
	(non_null_ref::non_null_deref_p): Delete.
	(non_null_ref::process_name): Delete.
	(ranger_cache::ranger_cache): Initialize m_exit object.
	(ranger_cache::fill_block_cache): Use m_exit object intead of nonnull.
	(ranger_cache::range_from_dom): Use side_effect class and m_exit object.
	(ranger_cache::update_to_nonnull): Delete.
	(non_null_loadstore): Delete.
	(ranger_cache::block_apply_nonnull): Delete.
	(ranger_cache::apply_side_effects): New.
	* gimple-range-cache.h (class non_null_ref): Delete.
	(non_null_ref::adjust_range): Delete.
	(class ranger_cache): Adjust prototypes, add side effect manager.
	* gimple-range-path.cc (path_range_query::range_defined_in_block): Use
	side effect manager for queries.
	(path_range_query::adjust_for_non_null_uses): Ditto.
	* gimple-range-path.h (class path_range_query): Delete non_null_ref.
	* gimple-range-side-effect.cc: New.
	* gimple-range-side-effect.h: New.
	* gimple-range.cc (gimple_ranger::gimple_ranger): Update contructor.
	(gimple_ranger::range_of_expr): Check def block for override value.
	(gimple_ranger::range_on_entry): Don't scan dominators for non-null.
	(gimple_ranger::range_on_edge): Check for outgoing side-effects.
	(gimple_ranger::register_side_effects): Call apply_side_effects.
	(enable_ranger): Update contructor.
	* gimple-range.h (class gimple_ranger): Update prototype.
	(enable_ranger): Update prototype.
	* tree-vrp.cc (execute_ranger_vrp): Invoke without immediate-use flag.