* ggc-zone.c (struct alloc_zone): Add statistics counters.
	(always_collect): New flag.
	(ggc_alloc_zone_1): Update statistics support.  Don't include
	overhead in allocated counter.
	(sweep_pages): Update allocated counter for large pages.  Don'y
	include overhead.
	(ggc_collect_1): Always collect.
	(ggc_collect): Honor always_collect flag.  Sum all zones to decide
	whether to collect.
	(SCALE, LABEL): New macros.
	(ggc_print_statistics): Add statistics support.

From-SVN: r85729