* Makefile.in: Add function.h to BASIC_BLOCK_H.  Remove all
	references to gt-tree-cfg.h.
	* basic-block.h (struct basic_block_def): Don't skip rbi
	for garbage collection.
	(struct reorder_block_def): Make GTY-able.
	(struct control_flow_graph): New structure.
	(n_edges, n_basic_blocks, last_basic_block, basic_block_info,
	BASIC_BLOCK, EXIT_BLOCK_PTR, ENTRY_BLOCK_PTR): No longer vars,
	but instead defines to the control_flow_graph for cfun.
	(label_to_block_map): New define, points to the label map of
	the control_flow_graph for cfun.
	(n_edges_for_function, n_basic_blocks_for_function,
	last_basic_block_for_function, basic_block_info_for_function,
	EXIT_BLOCK_PTR_FOR_FUNCTION, ENTRY_BLOCK_PTR_FOR_FUNCTION,
	basic_block_info_for_function, label_to_block_map_for_function):
	Counterparts for the above, taking a struct function as an extra
	argument.
	(alloc_rbi_pool, free_rbi_pool): Remove prototypes.
	* cfg.c: (n_edges, n_basic_blocks, last_basic_block,
	basic_block_info, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR): Remove.
	(alloc_rbi_pool, free_rbi_pool): Remove.
	(initialize_bb_rbi): Use ggc_alloc_cleared instead of pool_alloc.
	* cfglayout.c: (cfg_layout_initialize): Don't allocate the rbi pool
	here...
	(cfg_layout_finalize) ... and don't free it here.
	* cfgrtl.c (cfg_layout_delete_block): Zero out rbi so it gets
	garbage collected.
	* flow.c (free_basic_block_vars): Set label_to_block_map and
	n_edges to zero too.
	* function.h (struct function): Add cfg field.
	* function.c (allocate_struct_function): Allocate the cfg.
	* tree-cfg.c (label_to_block_map): Remove.
	(build_tree_cfg): Don't allocate the rbi pool here...
	(delete_tree_cfg_annotations): ...and don't free it here.
	Also don't nullify label_to_block_map for cfun.

Co-Authored-By: Jan Hubicka <jh@suse.cz>
Co-Authored-By: Stuart Hastings <stuart@apple.com>

From-SVN: r98048