Fix PR40886.

2010-02-11  Sebastian Pop  <sebastian.pop@amd.com>
	    Changpeng Fang  <changpeng.fang@amd.com>

	PR middle-end/40886
	* tree-ssa-loop-ivopts.c (determine_use_iv_cost_condition): Decrement
	the cost of an IV candidate when the IV is used in a test against zero.

	* gcc.dg/tree-ssa/ivopts-3.c: New.

Co-Authored-By: Changpeng Fang <changpeng.fang@amd.com>

From-SVN: r156701