2010-07-09  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/44852
	* tree-ssa-alias.c: Include toplev.h for exact_log2.
	(indirect_ref_may_alias_decl_p): Properly handle negative offsets
	in MEM_REF.
	(indirect_refs_may_alias_p): Likewise.
	* Makefile.in (tree-ssa-alias.o): Add $(TOPLEV_H).

	* gcc.c-torture/execute/pr44852.c: New testcase.

From-SVN: r161994