ggc-zone.c: Rewritten.

	* ggc-zone.c: Rewritten.

	* alloc-pool.c (dump_alloc_pool_statistics): Don't print statistics
	if there are none.
	* configure.ac: Define GGC_ZONE for --with-gc=zone.
	* config.in: Regenerated.
	* configure: Regenerated.
	* gentype.c (write_types_process_field, write_func_for_structure):
	Pass new argument to gt_pch_note_object.
	* ggc-common.c (struct ptr_data): Add TYPE.
	(gt_pch_note_object): Take TYPE argument and save it.
	(call_count): Update call to ggc_pch_count_object.
	(call_alloc): Update call to ggc_pch_alloc_object.
	(gt_pch_save): Call ggc_pch_prepare_write after paddng the PCH
	file.
	* ggc-none.c (rtl_zone, garbage_zone, ggc_alloc_zone_stat): Delete.
	* ggc-page.c (rtl_zone, tree_zone, garbage_zone)
	(ggc_alloc_zone_stat): Delete.
	(ggc_pch_count_object, ggc_pch_alloc_object): Add TYPE argument.
	* ggc.h (gt_pch_note_object, ggc_pch_count_object)
	(ggc_pch_alloc_object): Update prototypes.
	(garbage_zone): Delete.
	(tree_zone, rtl_zone, ggc_alloc_zone_stat, ggc_alloc_zone): Move to
	GGC_ZONE conditional.  Update.  Change tree_zone and rtl_zone into
	pointers.
	(tree_id_zone): New variable.
	(ggc_alloc_cleared_zone): Remove unused.
	(ggc_alloc_zone): Define.
	(ggc_alloc_rtvec, ggc_alloc_tree): Update to use ggc_alloc_zone.
	* rtl.c (rtx_alloc_stat, shallow_copy_rtx_stat): Use
	ggc_alloc_zone_stat.
	* stringpool.c (gt_pch_n_S): Update call to gt_pch_note_object.
	* tree.c (copy_node_stat, make_tree_binfo_stat, make_tree_vec_stat)
	(tree_cons_stat, build1_stat): Update call to ggc_alloc_zone_stat.
	(make_node_stat): Likewise.  Use tree_id_zone.

From-SVN: r96381