* ifcvt.c (struct noce_if_info): Add comments to the fields.
	Remove the b_unconditional field.
	(noce_try_sign_mask): Do not look at b_unconditional.
	(noce_process_if_block): Do not use merge_if_blocks.  Update
	the CFG here.  Do not set b_unconditional.
	(cond_move_process_if_block): Likewise.
	(find_cond_trap): Likewise.
	(check_cond_move_block): Require simple jump insns at the end
	of the basic block.

From-SVN: r120686