PR tree-optimization/33645
	* tree-ssa-live.c (mark_all_vars_used): Add data argument,
	pass it to walk_tree.
	(mark_all_vars_used_1): Pass data through to mark_all_vars_used.
	When calling set_is_used on a VAR_DECL, if data is not NULL and
	its DECL_UID is in the bitmap, call mark_all_vars_used on its
	DECL_INITIAL after clearing the bit in bitmap.
	(remove_unused_locals): Adjust mark_all_vars_used callers.
	Instead of removing unused global vars from unexpanded_var_list
	immediately record them in bitmap, call mark_all_vars_used on
	all used global vars from unexpanded_var_list and only purge
	global vars that weren't found used even during that step.

	* gcc.dg/pr33645-1.c: New test.
	* gcc.dg/pr33645-2.c: New test.
	* gcc.dg/pr33645-3.c: New test.

From-SVN: r129254