2012-09-06 Richard Guenther <rguenther@suse.de>

2012-09-06  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/54498
	* tree-ssa-alias.h (get_continuation_for_phi): Add flag to
	abort when reaching an already visited region.
	* tree-ssa-alias.c (maybe_skip_until): Likewise.  And do it.
	(get_continuation_for_phi_1): Likewise.
	(walk_non_aliased_vuses): When we translated the reference,
	abort when we re-visit a region.
	* tree-ssa-pre.c (translate_vuse_through_block): Adjust.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-4_7-branch@191031 138bc75d-0d04-0410-961f-82ee72b054a4