2010-03-29  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/43560
	* tree-ssa-loop-im.c (ref_always_accessed_p): Add store_p
	parameter.
	(can_sm_ref_p): Treat stores to readonly locations as
	trapping.

	* gcc.dg/torture/pr43560.c: New testcase.

From-SVN: r157799