doloop.c: Removed.

	* doloop.c: Removed.
	* loop-doloop.c: New file.
	* Makefile.in (doloop.o): Remove.
	(loop-doloop.o): New.
	* cfgloop.h (get_loop_level, doloop_optimize_loops): Declare.
	* cfgloopanal.c (get_loop_level): New function.
	* loop-iv.c (iv_number_of_iterations): Handle case when loop
	is leaved immediatelly.
	* loop.c (strength_reduce): Do not call doloop optimization.
	* loop.h (LOOP_BCT): Removed.
	* passes.c (rest_of_handle_loop_optimize): Do not use LOOP_BCT.
	(rest_of_handle_loop2): Call doloop_optimize_loops.
	(rest_of_compilation): Test for optimizations moved to
	rest_of_handle_loop2.

From-SVN: r79625