re PR tree-optimization/84775 (ICE on valid code at -O3: in check_loop_closed_ssa_def, at tree-ssa-loop-manip.c:709)

2018-03-09  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/84775
	* tree-if-conv.c (add_bb_predicate_gimplified_stmts): Delink
	immediate uses of predicate stmts and mark them modified.

	Revert
	PR tree-optimization/84178
	* tree-if-conv.c (combine_blocks): Move insert_gimplified_predicates
	to caller.
	(version_loop_for_if_conversion): Delay update_ssa call.
	(tree_if_conversion): Delay update_ssa until after predicate
	insertion.

	* gcc.dg/torture/pr84775.c: New testcase.

From-SVN: r258387