* flow.c (XNMALLOC): New macro.
	(flow_int_list_blocks, basic_block_succ, basic_block_pred): New
	static variables.
	(add_edge, add_edge_to_label): New static functions.
	(free_bb_memory): New function.
	(flow_delete_insn): Delete function.
	(basic_block_drops_in): Delete variable.
	(find_basic_blocks): Allocate and initialize basic_block_head,
	basic_block_succ.  Don't allocate basic_block_drops_in.
	Call free_bb_memory at the beginning.
	(find_basic_blocks_1): Don't do multiple passes.
	Delete code to compute basic_block_drops_in.
	After calling make_edges, mark blocks reached by current block live.
	Update test for unreachable live blocks.
	(mark_label_ref): Delete args X, CHECKDUP.  Add PRED arg.  All callers
	changed.
	Simplify to call add_edge_to_label when a LABEL_REF is found.
	(make_edges): Simplify to call add_edge_to_label instead of
	mark_label_ref most of the time.
	Compute here whether control drops into the next block.
	(delete_unreachable_blocks): Return void.  All callers changed.
	Delete unreachable blocks in reverse order.
	After deleting all unreachable blocks, renumber the remaining ones
	and update n_basic_blocks.
	(delete_block): Speed up deletion a bit.
	Don't set basic_block_drops_in for deleted blocks.
	(free_basic_block_vars): Don't free basic_block_drops_in.
	(life_analysis_1): Update to use new edge representation.
	(dump_flow_info): Delete code to print basic block info; call
	dump_bb_data instead.
	(compute_preds_succs): Delete code to recompute basic_block_drops_in
	and uid_block_number.
	Simply copy the previously computed cfg.
	(dump_bb_data): New arg LIVE_INFO.  All callers changed.
	Print register lifetime information if LIVE_INFO is nonzero.
	* basic-block.h (dump_bb_data): Adjust prototype.
	* gcse.c (gcse_main): Update call to dump_bb_data.
	* rtl.h (free_bb_memory): Declare.
	* toplev.c (rest_of_compilation): Call free_bb_memory.

From-SVN: r23443