[PATCH] const_and_copies is no longer file scoped

[PATCH] const_and_copies is no longer file scoped

        PR tree-optimization/47679
	* tree-ssa-dom.c (const_and_copies): No longer file scoped.  Move
	it here ...
	(dom_opt_dom_walker): New private member holding the const_and_copies
	object.  Update constructor.
	(pass_dominator::execute): Corresponding changes to declaration
	and initialization of const_and_copies.  Update constructor call
	for the dom_opt_dom_walker object.
	(record_temporary_equivalences): Accept const_and_copies argument
	pass it down to children as needed.
	(record_equality): Likewise.
	(record_equivalences_from_incoming_edge): Likewise.
	(cprop_into_successor_phis, optimize_stmt): Likewise.
	(eliminate_redundant_computations): Likewise.
	(dom_opt_dom_walker::thread_across_edge): Update access to
	const_and_copies object and pass it to children as needed.
	(dom_opt_dom_walker::before_dom_children): Similarly.
	(dom_opt_dom_walker::after_dom_children): Similarly.

From-SVN: r227922