re PR middle-end/30905 (Fails to cross-jump)

re PR middle-end/30905 (Fails to cross-jump)

2008-01-11  Steven Bosscher  <stevenb.gcc@gmail.com>

	PR rtl-optimization/30905
	* cfgcleanup.c: Include dce.h
	(crossjumps_occured): New global variable.
	(try_crossjump_bb): Exit loop after finding a fallthru edge.
	If something changed, set crossjumps_occured to true.
	(try_optimize_cfg): Clear crossjumps_occured at the beginning.
	Don't add/remove fake edges to exit here...
	(cleanup_cfg): ...but do it here, when crossjumping.
	Run a fast DCE when successful crossjumps occured in the latest
	iteration of try_optimize_cfg.

From-SVN: r131468