* tracer.c (tracer): Don't take FLAGS argument.  Assert we are
	in cfglayout mode.  Don't go into and out of cfglayout mode.
	Link the blocks in the order of the constructed traces.
	(rest_of_handle_tracer): Adjust call to tracer.
	* loop-init.c (rtl_loop_init): Assert we are in cfglayout mode.
	Don't go into cfglayout mode.
	(rtl_loop_done): Don't go out of cfglayout mode.
	* cfglayout.c (relink_block_chain): New function, split out from...
	(fixup_reorder_chain): ...here.  Remove redundant checking.
	(cfg_layout_finalize): Don't clear the header, footer, and aux
	fields here, move the code to do so to relink_block_chain.  Likewise
	for free_original_copy_tables.
	* rtl.h (tracer): Update prototype.
	* bb-reorder.c (reorder_basic_blocks): Don't take FLAGS argument.
	Assert we are in cfglayout mode.  Don't go into and out of cfglayout
	mode.  Use relink_block_chain to serialize the CFG according to the
	new basic block order.  Move targetm.cannot_modify_jumps_p check from
	here...
	(gate_handle_reorder_blocks): ...to here.
	(duplicate_computed_gotos): Move targetm.cannot_modify_jumps_p check
	from here...
	(gate_duplicate_computed_gotos): ...to here.
	(rest_of_handle_reorder_blocks): Don't see if anything has changed,
	something always changes when going into and out of cfglayout mode.
	Perform an expensive cfg cleanup while going into cfglayout mode.
	Always update liveness information on HAVE_conditional_execution
	targets.  Reserialize the basic blocks and go out of cfglayout mode.
	* reg-stack.c: Include cfglayout.h.
	(rest_of_handle_stack_regs): Go into and out of cfglayout mode around
	the call to reorder_basic_blocks.
	* basic-block.h (reorder_basic_blocks): Update prototype.
	(relink_block_chain): New prototype.
	* passes.c (pass_outof_cfg_layout_mode): Move after cse2.

From-SVN: r123167