tree-ssa-loop-ivopts.c (struct ivopts_data): New field iv_obstack.

tree-ssa-loop-ivopts.c (struct ivopts_data): New field iv_obstack.

	* tree-ssa-loop-ivopts.c (struct ivopts_data): New field iv_obstack.
	(tree_ssa_iv_optimize_init): Initialize iv_obstack.
	(alloc_iv): New parameter.  Allocate struct iv using obstack_alloc.
	(set_iv, find_interesting_uses_address, add_candidate_1): New
	argument to alloc_iv.
	(find_interesting_uses_op, find_interesting_uses_cond): Don't
	duplicate struct iv.
	(free_loop_data): Don't free struct iv explicitly.
	(tree_ssa_iv_optimize_finalize): Free iv_obstack.

From-SVN: r225293