* Makefile.in (GGC, GGC_LIB): New.
	(HOST_RTL): Include ggc-none.o.
	(ggc-simple.o): New target.
	(ggc-none.o): Likewise.
	* tree.h (tree_common): Add gc_mark.
	* rtl.h (struct rtx_def): Steal a bit from code to make gc_mark.
	(struct rtvec_def): Add gc_mark.
	* emit-rtl.c (global_rtl): Update static initializers to contain
	enough initializers.
	* ggc.h, ggc-none.c, ggc-simple.c: New files.
	* toplev.c (gc_time): New variable.
	(all_time): New variable.
	(compile_file): Print gc time.
	(print_time): Calculate percentage of the whole.

From-SVN: r29106