2016-08-17  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/23855
	* tree-ssa-loop-unswitch.c: Include tree-ssa-loop-manip.h.
	(tree_unswitch_outer_loop): Iterate find_loop_guard as long as we
	find guards to hoist.  Do not update SSA form but rewrite virtuals
	into loop closed SSA.
	(find_loop_guard): Adjust to skip already hoisted guards.  Do
	not mark virtuals for renaming or update SSA form.

	* gcc.dg/loop-unswitch-2.c: Adjust.

From-SVN: r239523