* basic-block.h (create_basic_block, merge_blocks_nomove): Kill.
	* cfgcleanup.c (merge_blocks): Rename to merge_blocks_move.
	(merge_blocks_move_predecessor_nojumps,
	 merge_blocks_move_successor_nojumps): Use merge_blocks.
	(try_optimize_cfg): Use merge_blocks_move.
	* cfgrtl.c (create_basic_block): Rename to rtl_create_basic_block.
	(merge_blocks_nomove): Rename to rtl_merge_blocks.
	(cfg_layout_create_basic_block): New.
	(rtl_can_merge_blocks): New.
	(cfg_layout_split_block): Do not alloc aux by hand.
	* cfghooks.h (cfg_hooks): Add create_basic_block, can_merge_blocks_p,
	merge_blocks.
	(create_basic_block, can_merge_blocks_p, merge_blocks): New macros.
	* cfglayout.c (cfg_layout_duplicate_bb): Do not allocate aux by hand.
	* cfgloopmanip.c (loop_split_edge_with): Likewise.
	* ifcvt.c (merge_if_block): Use merge_blocks_nomove.

	* basic-block.h (basic_block_def): Add field 'rbi'.
	* bb-reorder.c (find_traces, rotate_loop, mark_bb_visited,
	find_traces_1_round, copy_bb, connect_traces): Update use of rbi.
	* cfg.c (entry_exit_blocks): Add new field.
	* cfglayout.c: Include alloc-pool.h;
	(cfg_layout_pool): New.
	(record_effective_endpoints, fixup_reorder_chain,
	fixup_fallthru_exit_predecessor, cfg_layout_duplicate_bb): Update use
	of rbi.
	(cfg_layout_initialize_rbi): New function.
	(cfg_layout_initialize): Use it.
	(cfg_layout_finalize): Clear rbi fields.
	* cfglayout.h (RBI): Kill.
	(cfg_layout_initialize_rbi): Declare.
	* cfgloopmanip.c (copy_bbs): Use rbi.
	(record_exit_edges): Likewise.
	(duplicate_loop_to_header_edge): Likewise.
	* cfgrtl.c (cfg_layout_create_basic_block): Use
	cfg_layout_initialize_rbi.
	(cfg_layout_split_block): Use rbi.
	(cfg_layout_delete_block): Likewise.
	* loop-init.c (loop_optimizer_finalize): Likewise.
	* loop-unswitch.c (unswitch_loop): Likewise.
	* tracer.c (seen, tail_duplicate, layout_superblocks): Likewise.

	* cfgrtl.c: Update comments.
	(try_redirect_by_replacing_jump): New argument.
	(redirect_branch_edge): Break out from ...
	(rtl_redirect_edge_and_branch): ... this one.
	(update_cfg_after_block_merging): Break out from ...
	(rtl_merge_blocks): ... this one.
	(cfg_layout_split_edge): New.
	(cfg_layout_merge_blocks): New.
	(cfg_layout_can_merge_blocks_p): New.
	(cfg_layout_redirect_edge_and_branch): Reorganize.
	(cfg_layout_rtl_cfg_hooks): Fill in.
	(cfg_layout_delete_block): Kill barriers.
	* cfganal.c (can_fallthru): Deal with exit blocks
	* cfglayout.c (cfg_layout_function_header): New function
	(record_effective_endpoints): Record function header.
	(fixup_reorder_chain): Fixup dead jumptables; place header

	* basic-block.h (CLEANUP_CFGLAYOUT): New flag.
	* bb-reorder.c (cfg_layout_initialize): Update call.
	* cfgcleanup.c (try_optimize_cfg): Supress optimizations of fallthru
	edges in cfglayout mode.
	* cfglayout.c (cleanup_unconditional_jumps): Kill.
	(cfg_layout_initialize): Kill agrument loops; use cfgcleanup.
	* cfglayout.h (cfg_layout_initialize): Update prototype.
	* cfgloop.h (CP_INSIDE_CFGLAYOUT): Kill.
	* cfgloopmanip.c (loop_split_edge_with): Use split_edge.
	* flow.c (propagate_block): Do not crash when basic block ends
	by first insn in the chain.
	* loop-init.c (loop_optimizer_init):  First enter cfglayout mode; later
	do loop discovery.
	* tracer.c (tracer): Update call of cfg_layout_initialize.

From-SVN: r68899